Commit | Line | Data |
---|---|---|
bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
2b6080f2 | 4 | * Copyright (C) 2007-2012 Steven Rostedt <srostedt@redhat.com> |
bc0c38d1 SR |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
6d49e352 | 12 | * Copyright (C) 2004 Nadia Yvette Chambers |
bc0c38d1 | 13 | */ |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
273b281f | 15 | #include <generated/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
8434dc93 | 23 | #include <linux/tracefs.h> |
4c11d7ae | 24 | #include <linux/pagemap.h> |
bc0c38d1 SR |
25 | #include <linux/hardirq.h> |
26 | #include <linux/linkage.h> | |
27 | #include <linux/uaccess.h> | |
2cadf913 | 28 | #include <linux/kprobes.h> |
bc0c38d1 SR |
29 | #include <linux/ftrace.h> |
30 | #include <linux/module.h> | |
31 | #include <linux/percpu.h> | |
2cadf913 | 32 | #include <linux/splice.h> |
3f5a54e3 | 33 | #include <linux/kdebug.h> |
5f0c6c03 | 34 | #include <linux/string.h> |
f76180bc | 35 | #include <linux/mount.h> |
7e53bd42 | 36 | #include <linux/rwsem.h> |
5a0e3ad6 | 37 | #include <linux/slab.h> |
bc0c38d1 SR |
38 | #include <linux/ctype.h> |
39 | #include <linux/init.h> | |
2a2cc8f7 | 40 | #include <linux/poll.h> |
b892e5c8 | 41 | #include <linux/nmi.h> |
bc0c38d1 | 42 | #include <linux/fs.h> |
8bd75c77 | 43 | #include <linux/sched/rt.h> |
86387f7e | 44 | |
bc0c38d1 | 45 | #include "trace.h" |
f0868d1e | 46 | #include "trace_output.h" |
bc0c38d1 | 47 | |
73c5162a SR |
48 | /* |
49 | * On boot up, the ring buffer is set to the minimum size, so that | |
50 | * we do not waste memory on systems that are not using tracing. | |
51 | */ | |
55034cd6 | 52 | bool ring_buffer_expanded; |
73c5162a | 53 | |
8e1b82e0 FW |
54 | /* |
55 | * We need to change this state when a selftest is running. | |
ff32504f FW |
56 | * A selftest will lurk into the ring-buffer to count the |
57 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 58 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
59 | * at the same time, giving false positive or negative results. |
60 | */ | |
8e1b82e0 | 61 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 62 | |
b2821ae6 SR |
63 | /* |
64 | * If a tracer is running, we do not want to run SELFTEST. | |
65 | */ | |
020e5f85 | 66 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 67 | |
0daa2302 SRRH |
68 | /* Pipe tracepoints to printk */ |
69 | struct trace_iterator *tracepoint_print_iter; | |
70 | int tracepoint_printk; | |
71 | ||
adf9f195 FW |
72 | /* For tracers that don't implement custom flags */ |
73 | static struct tracer_opt dummy_tracer_opt[] = { | |
74 | { } | |
75 | }; | |
76 | ||
77 | static struct tracer_flags dummy_tracer_flags = { | |
78 | .val = 0, | |
79 | .opts = dummy_tracer_opt | |
80 | }; | |
81 | ||
8c1a49ae SRRH |
82 | static int |
83 | dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) | |
adf9f195 FW |
84 | { |
85 | return 0; | |
86 | } | |
0f048701 | 87 | |
7ffbd48d SR |
88 | /* |
89 | * To prevent the comm cache from being overwritten when no | |
90 | * tracing is active, only save the comm when a trace event | |
91 | * occurred. | |
92 | */ | |
93 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
94 | ||
0f048701 SR |
95 | /* |
96 | * Kill all tracing for good (never come back). | |
97 | * It is initialized to 1 but will turn to zero if the initialization | |
98 | * of the tracer is successful. But that is the only place that sets | |
99 | * this back to zero. | |
100 | */ | |
4fd27358 | 101 | static int tracing_disabled = 1; |
0f048701 | 102 | |
9288f99a | 103 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 104 | |
955b61e5 | 105 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 106 | |
944ac425 SR |
107 | /* |
108 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
109 | * | |
110 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
111 | * is set, then ftrace_dump is called. This will output the contents | |
112 | * of the ftrace buffers to the console. This is very useful for | |
113 | * capturing traces that lead to crashes and outputing it to a | |
114 | * serial console. | |
115 | * | |
116 | * It is default off, but you can enable it with either specifying | |
117 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
118 | * /proc/sys/kernel/ftrace_dump_on_oops |
119 | * Set 1 if you want to dump buffers of all CPUs | |
120 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 121 | */ |
cecbca96 FW |
122 | |
123 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 124 | |
de7edd31 SRRH |
125 | /* When set, tracing will stop when a WARN*() is hit */ |
126 | int __disable_trace_on_warning; | |
127 | ||
607e2ea1 | 128 | static int tracing_set_tracer(struct trace_array *tr, const char *buf); |
b2821ae6 | 129 | |
ee6c2c1b LZ |
130 | #define MAX_TRACER_SIZE 100 |
131 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 132 | static char *default_bootup_tracer; |
d9e54076 | 133 | |
55034cd6 SRRH |
134 | static bool allocate_snapshot; |
135 | ||
1beee96b | 136 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 137 | { |
67012ab1 | 138 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 139 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 140 | /* We are using ftrace early, expand it */ |
55034cd6 | 141 | ring_buffer_expanded = true; |
d9e54076 PZ |
142 | return 1; |
143 | } | |
1beee96b | 144 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 145 | |
944ac425 SR |
146 | static int __init set_ftrace_dump_on_oops(char *str) |
147 | { | |
cecbca96 FW |
148 | if (*str++ != '=' || !*str) { |
149 | ftrace_dump_on_oops = DUMP_ALL; | |
150 | return 1; | |
151 | } | |
152 | ||
153 | if (!strcmp("orig_cpu", str)) { | |
154 | ftrace_dump_on_oops = DUMP_ORIG; | |
155 | return 1; | |
156 | } | |
157 | ||
158 | return 0; | |
944ac425 SR |
159 | } |
160 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 161 | |
de7edd31 SRRH |
162 | static int __init stop_trace_on_warning(char *str) |
163 | { | |
933ff9f2 LCG |
164 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) |
165 | __disable_trace_on_warning = 1; | |
de7edd31 SRRH |
166 | return 1; |
167 | } | |
933ff9f2 | 168 | __setup("traceoff_on_warning", stop_trace_on_warning); |
de7edd31 | 169 | |
3209cff4 | 170 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
171 | { |
172 | allocate_snapshot = true; | |
173 | /* We also need the main ring buffer expanded */ | |
174 | ring_buffer_expanded = true; | |
175 | return 1; | |
176 | } | |
3209cff4 | 177 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 178 | |
7bcfaf54 SR |
179 | |
180 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
181 | static char *trace_boot_options __initdata; | |
182 | ||
183 | static int __init set_trace_boot_options(char *str) | |
184 | { | |
67012ab1 | 185 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
186 | trace_boot_options = trace_boot_options_buf; |
187 | return 0; | |
188 | } | |
189 | __setup("trace_options=", set_trace_boot_options); | |
190 | ||
e1e232ca SR |
191 | static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; |
192 | static char *trace_boot_clock __initdata; | |
193 | ||
194 | static int __init set_trace_boot_clock(char *str) | |
195 | { | |
196 | strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); | |
197 | trace_boot_clock = trace_boot_clock_buf; | |
198 | return 0; | |
199 | } | |
200 | __setup("trace_clock=", set_trace_boot_clock); | |
201 | ||
0daa2302 SRRH |
202 | static int __init set_tracepoint_printk(char *str) |
203 | { | |
204 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) | |
205 | tracepoint_printk = 1; | |
206 | return 1; | |
207 | } | |
208 | __setup("tp_printk", set_tracepoint_printk); | |
de7edd31 | 209 | |
cf8e3474 | 210 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
211 | { |
212 | nsec += 500; | |
213 | do_div(nsec, 1000); | |
214 | return nsec; | |
215 | } | |
216 | ||
4fcdae83 SR |
217 | /* |
218 | * The global_trace is the descriptor that holds the tracing | |
219 | * buffers for the live tracing. For each CPU, it contains | |
220 | * a link list of pages that will store trace entries. The | |
221 | * page descriptor of the pages in the memory is used to hold | |
222 | * the link list by linking the lru item in the page descriptor | |
223 | * to each of the pages in the buffer per CPU. | |
224 | * | |
225 | * For each active CPU there is a data field that holds the | |
226 | * pages for the buffer for that CPU. Each CPU has the same number | |
227 | * of pages allocated for its buffer. | |
228 | */ | |
bc0c38d1 SR |
229 | static struct trace_array global_trace; |
230 | ||
ae63b31e | 231 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 232 | |
ff451961 SRRH |
233 | int trace_array_get(struct trace_array *this_tr) |
234 | { | |
235 | struct trace_array *tr; | |
236 | int ret = -ENODEV; | |
237 | ||
238 | mutex_lock(&trace_types_lock); | |
239 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
240 | if (tr == this_tr) { | |
241 | tr->ref++; | |
242 | ret = 0; | |
243 | break; | |
244 | } | |
245 | } | |
246 | mutex_unlock(&trace_types_lock); | |
247 | ||
248 | return ret; | |
249 | } | |
250 | ||
251 | static void __trace_array_put(struct trace_array *this_tr) | |
252 | { | |
253 | WARN_ON(!this_tr->ref); | |
254 | this_tr->ref--; | |
255 | } | |
256 | ||
257 | void trace_array_put(struct trace_array *this_tr) | |
258 | { | |
259 | mutex_lock(&trace_types_lock); | |
260 | __trace_array_put(this_tr); | |
261 | mutex_unlock(&trace_types_lock); | |
262 | } | |
263 | ||
f306cc82 TZ |
264 | int filter_check_discard(struct ftrace_event_file *file, void *rec, |
265 | struct ring_buffer *buffer, | |
266 | struct ring_buffer_event *event) | |
eb02ce01 | 267 | { |
f306cc82 TZ |
268 | if (unlikely(file->flags & FTRACE_EVENT_FL_FILTERED) && |
269 | !filter_match_preds(file->filter, rec)) { | |
270 | ring_buffer_discard_commit(buffer, event); | |
271 | return 1; | |
272 | } | |
273 | ||
274 | return 0; | |
275 | } | |
276 | EXPORT_SYMBOL_GPL(filter_check_discard); | |
277 | ||
278 | int call_filter_check_discard(struct ftrace_event_call *call, void *rec, | |
279 | struct ring_buffer *buffer, | |
280 | struct ring_buffer_event *event) | |
281 | { | |
282 | if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && | |
283 | !filter_match_preds(call->filter, rec)) { | |
284 | ring_buffer_discard_commit(buffer, event); | |
285 | return 1; | |
286 | } | |
287 | ||
288 | return 0; | |
eb02ce01 | 289 | } |
f306cc82 | 290 | EXPORT_SYMBOL_GPL(call_filter_check_discard); |
eb02ce01 | 291 | |
ad1438a0 | 292 | static cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) |
37886f6a SR |
293 | { |
294 | u64 ts; | |
295 | ||
296 | /* Early boot up does not have a buffer yet */ | |
9457158b | 297 | if (!buf->buffer) |
37886f6a SR |
298 | return trace_clock_local(); |
299 | ||
9457158b AL |
300 | ts = ring_buffer_time_stamp(buf->buffer, cpu); |
301 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); | |
37886f6a SR |
302 | |
303 | return ts; | |
304 | } | |
bc0c38d1 | 305 | |
9457158b AL |
306 | cycle_t ftrace_now(int cpu) |
307 | { | |
308 | return buffer_ftrace_now(&global_trace.trace_buffer, cpu); | |
309 | } | |
310 | ||
10246fa3 SRRH |
311 | /** |
312 | * tracing_is_enabled - Show if global_trace has been disabled | |
313 | * | |
314 | * Shows if the global trace has been enabled or not. It uses the | |
315 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
316 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
317 | * need to know the accurate state, use tracing_is_on() which is a little | |
318 | * slower, but accurate. | |
319 | */ | |
9036990d SR |
320 | int tracing_is_enabled(void) |
321 | { | |
10246fa3 SRRH |
322 | /* |
323 | * For quick access (irqsoff uses this in fast path), just | |
324 | * return the mirror variable of the state of the ring buffer. | |
325 | * It's a little racy, but we don't really care. | |
326 | */ | |
327 | smp_rmb(); | |
328 | return !global_trace.buffer_disabled; | |
9036990d SR |
329 | } |
330 | ||
4fcdae83 | 331 | /* |
3928a8a2 SR |
332 | * trace_buf_size is the size in bytes that is allocated |
333 | * for a buffer. Note, the number of bytes is always rounded | |
334 | * to page size. | |
3f5a54e3 SR |
335 | * |
336 | * This number is purposely set to a low number of 16384. | |
337 | * If the dump on oops happens, it will be much appreciated | |
338 | * to not have to wait for all that output. Anyway this can be | |
339 | * boot time and run time configurable. | |
4fcdae83 | 340 | */ |
3928a8a2 | 341 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 342 | |
3928a8a2 | 343 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 344 | |
4fcdae83 | 345 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 346 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 347 | |
4fcdae83 SR |
348 | /* |
349 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 350 | */ |
a8227415 | 351 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 352 | |
7e53bd42 LJ |
353 | /* |
354 | * serialize the access of the ring buffer | |
355 | * | |
356 | * ring buffer serializes readers, but it is low level protection. | |
357 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
358 | * are not protected by ring buffer. | |
359 | * | |
360 | * The content of events may become garbage if we allow other process consumes | |
361 | * these events concurrently: | |
362 | * A) the page of the consumed events may become a normal page | |
363 | * (not reader page) in ring buffer, and this page will be rewrited | |
364 | * by events producer. | |
365 | * B) The page of the consumed events may become a page for splice_read, | |
366 | * and this page will be returned to system. | |
367 | * | |
368 | * These primitives allow multi process access to different cpu ring buffer | |
369 | * concurrently. | |
370 | * | |
371 | * These primitives don't distinguish read-only and read-consume access. | |
372 | * Multi read-only access are also serialized. | |
373 | */ | |
374 | ||
375 | #ifdef CONFIG_SMP | |
376 | static DECLARE_RWSEM(all_cpu_access_lock); | |
377 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
378 | ||
379 | static inline void trace_access_lock(int cpu) | |
380 | { | |
ae3b5093 | 381 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
382 | /* gain it for accessing the whole ring buffer. */ |
383 | down_write(&all_cpu_access_lock); | |
384 | } else { | |
385 | /* gain it for accessing a cpu ring buffer. */ | |
386 | ||
ae3b5093 | 387 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
388 | down_read(&all_cpu_access_lock); |
389 | ||
390 | /* Secondly block other access to this @cpu ring buffer. */ | |
391 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
392 | } | |
393 | } | |
394 | ||
395 | static inline void trace_access_unlock(int cpu) | |
396 | { | |
ae3b5093 | 397 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
398 | up_write(&all_cpu_access_lock); |
399 | } else { | |
400 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
401 | up_read(&all_cpu_access_lock); | |
402 | } | |
403 | } | |
404 | ||
405 | static inline void trace_access_lock_init(void) | |
406 | { | |
407 | int cpu; | |
408 | ||
409 | for_each_possible_cpu(cpu) | |
410 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
411 | } | |
412 | ||
413 | #else | |
414 | ||
415 | static DEFINE_MUTEX(access_lock); | |
416 | ||
417 | static inline void trace_access_lock(int cpu) | |
418 | { | |
419 | (void)cpu; | |
420 | mutex_lock(&access_lock); | |
421 | } | |
422 | ||
423 | static inline void trace_access_unlock(int cpu) | |
424 | { | |
425 | (void)cpu; | |
426 | mutex_unlock(&access_lock); | |
427 | } | |
428 | ||
429 | static inline void trace_access_lock_init(void) | |
430 | { | |
431 | } | |
432 | ||
433 | #endif | |
434 | ||
ee6bce52 | 435 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 436 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 437 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 | 438 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
328df475 | 439 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION; |
e7e2ee89 | 440 | |
5280bcef | 441 | static void tracer_tracing_on(struct trace_array *tr) |
10246fa3 SRRH |
442 | { |
443 | if (tr->trace_buffer.buffer) | |
444 | ring_buffer_record_on(tr->trace_buffer.buffer); | |
445 | /* | |
446 | * This flag is looked at when buffers haven't been allocated | |
447 | * yet, or by some tracers (like irqsoff), that just want to | |
448 | * know if the ring buffer has been disabled, but it can handle | |
449 | * races of where it gets disabled but we still do a record. | |
450 | * As the check is in the fast path of the tracers, it is more | |
451 | * important to be fast than accurate. | |
452 | */ | |
453 | tr->buffer_disabled = 0; | |
454 | /* Make the flag seen by readers */ | |
455 | smp_wmb(); | |
456 | } | |
457 | ||
499e5470 SR |
458 | /** |
459 | * tracing_on - enable tracing buffers | |
460 | * | |
461 | * This function enables tracing buffers that may have been | |
462 | * disabled with tracing_off. | |
463 | */ | |
464 | void tracing_on(void) | |
465 | { | |
10246fa3 | 466 | tracer_tracing_on(&global_trace); |
499e5470 SR |
467 | } |
468 | EXPORT_SYMBOL_GPL(tracing_on); | |
469 | ||
09ae7234 SRRH |
470 | /** |
471 | * __trace_puts - write a constant string into the trace buffer. | |
472 | * @ip: The address of the caller | |
473 | * @str: The constant string to write | |
474 | * @size: The size of the string. | |
475 | */ | |
476 | int __trace_puts(unsigned long ip, const char *str, int size) | |
477 | { | |
478 | struct ring_buffer_event *event; | |
479 | struct ring_buffer *buffer; | |
480 | struct print_entry *entry; | |
481 | unsigned long irq_flags; | |
482 | int alloc; | |
8abfb872 J |
483 | int pc; |
484 | ||
f0160a5a J |
485 | if (!(trace_flags & TRACE_ITER_PRINTK)) |
486 | return 0; | |
487 | ||
8abfb872 | 488 | pc = preempt_count(); |
09ae7234 | 489 | |
3132e107 SRRH |
490 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
491 | return 0; | |
492 | ||
09ae7234 SRRH |
493 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ |
494 | ||
495 | local_save_flags(irq_flags); | |
496 | buffer = global_trace.trace_buffer.buffer; | |
497 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, | |
8abfb872 | 498 | irq_flags, pc); |
09ae7234 SRRH |
499 | if (!event) |
500 | return 0; | |
501 | ||
502 | entry = ring_buffer_event_data(event); | |
503 | entry->ip = ip; | |
504 | ||
505 | memcpy(&entry->buf, str, size); | |
506 | ||
507 | /* Add a newline if necessary */ | |
508 | if (entry->buf[size - 1] != '\n') { | |
509 | entry->buf[size] = '\n'; | |
510 | entry->buf[size + 1] = '\0'; | |
511 | } else | |
512 | entry->buf[size] = '\0'; | |
513 | ||
514 | __buffer_unlock_commit(buffer, event); | |
8abfb872 | 515 | ftrace_trace_stack(buffer, irq_flags, 4, pc); |
09ae7234 SRRH |
516 | |
517 | return size; | |
518 | } | |
519 | EXPORT_SYMBOL_GPL(__trace_puts); | |
520 | ||
521 | /** | |
522 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
523 | * @ip: The address of the caller | |
524 | * @str: The constant string to write to the buffer to | |
525 | */ | |
526 | int __trace_bputs(unsigned long ip, const char *str) | |
527 | { | |
528 | struct ring_buffer_event *event; | |
529 | struct ring_buffer *buffer; | |
530 | struct bputs_entry *entry; | |
531 | unsigned long irq_flags; | |
532 | int size = sizeof(struct bputs_entry); | |
8abfb872 J |
533 | int pc; |
534 | ||
f0160a5a J |
535 | if (!(trace_flags & TRACE_ITER_PRINTK)) |
536 | return 0; | |
537 | ||
8abfb872 | 538 | pc = preempt_count(); |
09ae7234 | 539 | |
3132e107 SRRH |
540 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
541 | return 0; | |
542 | ||
09ae7234 SRRH |
543 | local_save_flags(irq_flags); |
544 | buffer = global_trace.trace_buffer.buffer; | |
545 | event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, | |
8abfb872 | 546 | irq_flags, pc); |
09ae7234 SRRH |
547 | if (!event) |
548 | return 0; | |
549 | ||
550 | entry = ring_buffer_event_data(event); | |
551 | entry->ip = ip; | |
552 | entry->str = str; | |
553 | ||
554 | __buffer_unlock_commit(buffer, event); | |
8abfb872 | 555 | ftrace_trace_stack(buffer, irq_flags, 4, pc); |
09ae7234 SRRH |
556 | |
557 | return 1; | |
558 | } | |
559 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
560 | ||
ad909e21 SRRH |
561 | #ifdef CONFIG_TRACER_SNAPSHOT |
562 | /** | |
563 | * trace_snapshot - take a snapshot of the current buffer. | |
564 | * | |
565 | * This causes a swap between the snapshot buffer and the current live | |
566 | * tracing buffer. You can use this to take snapshots of the live | |
567 | * trace when some condition is triggered, but continue to trace. | |
568 | * | |
569 | * Note, make sure to allocate the snapshot with either | |
570 | * a tracing_snapshot_alloc(), or by doing it manually | |
571 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
572 | * | |
573 | * If the snapshot buffer is not allocated, it will stop tracing. | |
574 | * Basically making a permanent snapshot. | |
575 | */ | |
576 | void tracing_snapshot(void) | |
577 | { | |
578 | struct trace_array *tr = &global_trace; | |
579 | struct tracer *tracer = tr->current_trace; | |
580 | unsigned long flags; | |
581 | ||
1b22e382 SRRH |
582 | if (in_nmi()) { |
583 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
584 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
585 | return; | |
586 | } | |
587 | ||
ad909e21 | 588 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
589 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
590 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
591 | tracing_off(); |
592 | return; | |
593 | } | |
594 | ||
595 | /* Note, snapshot can not be used when the tracer uses it */ | |
596 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
597 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
598 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
599 | return; |
600 | } | |
601 | ||
602 | local_irq_save(flags); | |
603 | update_max_tr(tr, current, smp_processor_id()); | |
604 | local_irq_restore(flags); | |
605 | } | |
1b22e382 | 606 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
607 | |
608 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
609 | struct trace_buffer *size_buf, int cpu_id); | |
3209cff4 SRRH |
610 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); |
611 | ||
612 | static int alloc_snapshot(struct trace_array *tr) | |
613 | { | |
614 | int ret; | |
615 | ||
616 | if (!tr->allocated_snapshot) { | |
617 | ||
618 | /* allocate spare buffer */ | |
619 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
620 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
621 | if (ret < 0) | |
622 | return ret; | |
623 | ||
624 | tr->allocated_snapshot = true; | |
625 | } | |
626 | ||
627 | return 0; | |
628 | } | |
629 | ||
ad1438a0 | 630 | static void free_snapshot(struct trace_array *tr) |
3209cff4 SRRH |
631 | { |
632 | /* | |
633 | * We don't free the ring buffer. instead, resize it because | |
634 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
635 | * we want preserve it. | |
636 | */ | |
637 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
638 | set_buffer_entries(&tr->max_buffer, 1); | |
639 | tracing_reset_online_cpus(&tr->max_buffer); | |
640 | tr->allocated_snapshot = false; | |
641 | } | |
ad909e21 | 642 | |
93e31ffb TZ |
643 | /** |
644 | * tracing_alloc_snapshot - allocate snapshot buffer. | |
645 | * | |
646 | * This only allocates the snapshot buffer if it isn't already | |
647 | * allocated - it doesn't also take a snapshot. | |
648 | * | |
649 | * This is meant to be used in cases where the snapshot buffer needs | |
650 | * to be set up for events that can't sleep but need to be able to | |
651 | * trigger a snapshot. | |
652 | */ | |
653 | int tracing_alloc_snapshot(void) | |
654 | { | |
655 | struct trace_array *tr = &global_trace; | |
656 | int ret; | |
657 | ||
658 | ret = alloc_snapshot(tr); | |
659 | WARN_ON(ret < 0); | |
660 | ||
661 | return ret; | |
662 | } | |
663 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
664 | ||
ad909e21 SRRH |
665 | /** |
666 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
667 | * | |
668 | * This is similar to trace_snapshot(), but it will allocate the | |
669 | * snapshot buffer if it isn't already allocated. Use this only | |
670 | * where it is safe to sleep, as the allocation may sleep. | |
671 | * | |
672 | * This causes a swap between the snapshot buffer and the current live | |
673 | * tracing buffer. You can use this to take snapshots of the live | |
674 | * trace when some condition is triggered, but continue to trace. | |
675 | */ | |
676 | void tracing_snapshot_alloc(void) | |
677 | { | |
ad909e21 SRRH |
678 | int ret; |
679 | ||
93e31ffb TZ |
680 | ret = tracing_alloc_snapshot(); |
681 | if (ret < 0) | |
3209cff4 | 682 | return; |
ad909e21 SRRH |
683 | |
684 | tracing_snapshot(); | |
685 | } | |
1b22e382 | 686 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
687 | #else |
688 | void tracing_snapshot(void) | |
689 | { | |
690 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
691 | } | |
1b22e382 | 692 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
93e31ffb TZ |
693 | int tracing_alloc_snapshot(void) |
694 | { | |
695 | WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); | |
696 | return -ENODEV; | |
697 | } | |
698 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
ad909e21 SRRH |
699 | void tracing_snapshot_alloc(void) |
700 | { | |
701 | /* Give warning */ | |
702 | tracing_snapshot(); | |
703 | } | |
1b22e382 | 704 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
705 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
706 | ||
5280bcef | 707 | static void tracer_tracing_off(struct trace_array *tr) |
10246fa3 SRRH |
708 | { |
709 | if (tr->trace_buffer.buffer) | |
710 | ring_buffer_record_off(tr->trace_buffer.buffer); | |
711 | /* | |
712 | * This flag is looked at when buffers haven't been allocated | |
713 | * yet, or by some tracers (like irqsoff), that just want to | |
714 | * know if the ring buffer has been disabled, but it can handle | |
715 | * races of where it gets disabled but we still do a record. | |
716 | * As the check is in the fast path of the tracers, it is more | |
717 | * important to be fast than accurate. | |
718 | */ | |
719 | tr->buffer_disabled = 1; | |
720 | /* Make the flag seen by readers */ | |
721 | smp_wmb(); | |
722 | } | |
723 | ||
499e5470 SR |
724 | /** |
725 | * tracing_off - turn off tracing buffers | |
726 | * | |
727 | * This function stops the tracing buffers from recording data. | |
728 | * It does not disable any overhead the tracers themselves may | |
729 | * be causing. This function simply causes all recording to | |
730 | * the ring buffers to fail. | |
731 | */ | |
732 | void tracing_off(void) | |
733 | { | |
10246fa3 | 734 | tracer_tracing_off(&global_trace); |
499e5470 SR |
735 | } |
736 | EXPORT_SYMBOL_GPL(tracing_off); | |
737 | ||
de7edd31 SRRH |
738 | void disable_trace_on_warning(void) |
739 | { | |
740 | if (__disable_trace_on_warning) | |
741 | tracing_off(); | |
742 | } | |
743 | ||
10246fa3 SRRH |
744 | /** |
745 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
746 | * @tr : the trace array to know if ring buffer is enabled | |
747 | * | |
748 | * Shows real state of the ring buffer if it is enabled or not. | |
749 | */ | |
5280bcef | 750 | static int tracer_tracing_is_on(struct trace_array *tr) |
10246fa3 SRRH |
751 | { |
752 | if (tr->trace_buffer.buffer) | |
753 | return ring_buffer_record_is_on(tr->trace_buffer.buffer); | |
754 | return !tr->buffer_disabled; | |
755 | } | |
756 | ||
499e5470 SR |
757 | /** |
758 | * tracing_is_on - show state of ring buffers enabled | |
759 | */ | |
760 | int tracing_is_on(void) | |
761 | { | |
10246fa3 | 762 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
763 | } |
764 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
765 | ||
3928a8a2 | 766 | static int __init set_buf_size(char *str) |
bc0c38d1 | 767 | { |
3928a8a2 | 768 | unsigned long buf_size; |
c6caeeb1 | 769 | |
bc0c38d1 SR |
770 | if (!str) |
771 | return 0; | |
9d612bef | 772 | buf_size = memparse(str, &str); |
c6caeeb1 | 773 | /* nr_entries can not be zero */ |
9d612bef | 774 | if (buf_size == 0) |
c6caeeb1 | 775 | return 0; |
3928a8a2 | 776 | trace_buf_size = buf_size; |
bc0c38d1 SR |
777 | return 1; |
778 | } | |
3928a8a2 | 779 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 780 | |
0e950173 TB |
781 | static int __init set_tracing_thresh(char *str) |
782 | { | |
87abb3b1 | 783 | unsigned long threshold; |
0e950173 TB |
784 | int ret; |
785 | ||
786 | if (!str) | |
787 | return 0; | |
bcd83ea6 | 788 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
789 | if (ret < 0) |
790 | return 0; | |
87abb3b1 | 791 | tracing_thresh = threshold * 1000; |
0e950173 TB |
792 | return 1; |
793 | } | |
794 | __setup("tracing_thresh=", set_tracing_thresh); | |
795 | ||
57f50be1 SR |
796 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
797 | { | |
798 | return nsecs / 1000; | |
799 | } | |
800 | ||
4fcdae83 | 801 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
802 | static const char *trace_options[] = { |
803 | "print-parent", | |
804 | "sym-offset", | |
805 | "sym-addr", | |
806 | "verbose", | |
f9896bf3 | 807 | "raw", |
5e3ca0ec | 808 | "hex", |
cb0f12aa | 809 | "bin", |
2a2cc8f7 | 810 | "block", |
86387f7e | 811 | "stacktrace", |
5e1607a0 | 812 | "trace_printk", |
b2a866f9 | 813 | "ftrace_preempt", |
9f029e83 | 814 | "branch", |
12ef7d44 | 815 | "annotate", |
02b67518 | 816 | "userstacktrace", |
b54d3de9 | 817 | "sym-userobj", |
66896a85 | 818 | "printk-msg-only", |
c4a8e8be | 819 | "context-info", |
c032ef64 | 820 | "latency-format", |
be6f164a | 821 | "sleep-time", |
a2a16d6a | 822 | "graph-time", |
e870e9a1 | 823 | "record-cmd", |
750912fa | 824 | "overwrite", |
cf30cf67 | 825 | "disable_on_free", |
77271ce4 | 826 | "irq-info", |
5224c3a3 | 827 | "markers", |
328df475 | 828 | "function-trace", |
bc0c38d1 SR |
829 | NULL |
830 | }; | |
831 | ||
5079f326 Z |
832 | static struct { |
833 | u64 (*func)(void); | |
834 | const char *name; | |
8be0709f | 835 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 836 | } trace_clocks[] = { |
1b3e5c09 TG |
837 | { trace_clock_local, "local", 1 }, |
838 | { trace_clock_global, "global", 1 }, | |
839 | { trace_clock_counter, "counter", 0 }, | |
e7fda6c4 | 840 | { trace_clock_jiffies, "uptime", 0 }, |
1b3e5c09 TG |
841 | { trace_clock, "perf", 1 }, |
842 | { ktime_get_mono_fast_ns, "mono", 1 }, | |
8cbd9cc6 | 843 | ARCH_TRACE_CLOCKS |
5079f326 Z |
844 | }; |
845 | ||
b63f39ea | 846 | /* |
847 | * trace_parser_get_init - gets the buffer for trace parser | |
848 | */ | |
849 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
850 | { | |
851 | memset(parser, 0, sizeof(*parser)); | |
852 | ||
853 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
854 | if (!parser->buffer) | |
855 | return 1; | |
856 | ||
857 | parser->size = size; | |
858 | return 0; | |
859 | } | |
860 | ||
861 | /* | |
862 | * trace_parser_put - frees the buffer for trace parser | |
863 | */ | |
864 | void trace_parser_put(struct trace_parser *parser) | |
865 | { | |
866 | kfree(parser->buffer); | |
867 | } | |
868 | ||
869 | /* | |
870 | * trace_get_user - reads the user input string separated by space | |
871 | * (matched by isspace(ch)) | |
872 | * | |
873 | * For each string found the 'struct trace_parser' is updated, | |
874 | * and the function returns. | |
875 | * | |
876 | * Returns number of bytes read. | |
877 | * | |
878 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
879 | */ | |
880 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
881 | size_t cnt, loff_t *ppos) | |
882 | { | |
883 | char ch; | |
884 | size_t read = 0; | |
885 | ssize_t ret; | |
886 | ||
887 | if (!*ppos) | |
888 | trace_parser_clear(parser); | |
889 | ||
890 | ret = get_user(ch, ubuf++); | |
891 | if (ret) | |
892 | goto out; | |
893 | ||
894 | read++; | |
895 | cnt--; | |
896 | ||
897 | /* | |
898 | * The parser is not finished with the last write, | |
899 | * continue reading the user input without skipping spaces. | |
900 | */ | |
901 | if (!parser->cont) { | |
902 | /* skip white space */ | |
903 | while (cnt && isspace(ch)) { | |
904 | ret = get_user(ch, ubuf++); | |
905 | if (ret) | |
906 | goto out; | |
907 | read++; | |
908 | cnt--; | |
909 | } | |
910 | ||
911 | /* only spaces were written */ | |
912 | if (isspace(ch)) { | |
913 | *ppos += read; | |
914 | ret = read; | |
915 | goto out; | |
916 | } | |
917 | ||
918 | parser->idx = 0; | |
919 | } | |
920 | ||
921 | /* read the non-space input */ | |
922 | while (cnt && !isspace(ch)) { | |
3c235a33 | 923 | if (parser->idx < parser->size - 1) |
b63f39ea | 924 | parser->buffer[parser->idx++] = ch; |
925 | else { | |
926 | ret = -EINVAL; | |
927 | goto out; | |
928 | } | |
929 | ret = get_user(ch, ubuf++); | |
930 | if (ret) | |
931 | goto out; | |
932 | read++; | |
933 | cnt--; | |
934 | } | |
935 | ||
936 | /* We either got finished input or we have to wait for another call. */ | |
937 | if (isspace(ch)) { | |
938 | parser->buffer[parser->idx] = 0; | |
939 | parser->cont = false; | |
057db848 | 940 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 941 | parser->cont = true; |
942 | parser->buffer[parser->idx++] = ch; | |
057db848 SR |
943 | } else { |
944 | ret = -EINVAL; | |
945 | goto out; | |
b63f39ea | 946 | } |
947 | ||
948 | *ppos += read; | |
949 | ret = read; | |
950 | ||
951 | out: | |
952 | return ret; | |
953 | } | |
954 | ||
3a161d99 | 955 | /* TODO add a seq_buf_to_buffer() */ |
b8b94265 | 956 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
957 | { |
958 | int len; | |
3c56819b | 959 | |
5ac48378 | 960 | if (trace_seq_used(s) <= s->seq.readpos) |
3c56819b EGM |
961 | return -EBUSY; |
962 | ||
5ac48378 | 963 | len = trace_seq_used(s) - s->seq.readpos; |
3c56819b EGM |
964 | if (cnt > len) |
965 | cnt = len; | |
3a161d99 | 966 | memcpy(buf, s->buffer + s->seq.readpos, cnt); |
3c56819b | 967 | |
3a161d99 | 968 | s->seq.readpos += cnt; |
3c56819b EGM |
969 | return cnt; |
970 | } | |
971 | ||
0e950173 TB |
972 | unsigned long __read_mostly tracing_thresh; |
973 | ||
5d4a9dba | 974 | #ifdef CONFIG_TRACER_MAX_TRACE |
5d4a9dba SR |
975 | /* |
976 | * Copy the new maximum trace into the separate maximum-trace | |
977 | * structure. (this way the maximum trace is permanently saved, | |
978 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
979 | */ | |
980 | static void | |
981 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
982 | { | |
12883efb SRRH |
983 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
984 | struct trace_buffer *max_buf = &tr->max_buffer; | |
985 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
986 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 987 | |
12883efb SRRH |
988 | max_buf->cpu = cpu; |
989 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 990 | |
6d9b3fa5 | 991 | max_data->saved_latency = tr->max_latency; |
8248ac05 SR |
992 | max_data->critical_start = data->critical_start; |
993 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 994 | |
1acaa1b2 | 995 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 996 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
997 | /* |
998 | * If tsk == current, then use current_uid(), as that does not use | |
999 | * RCU. The irq tracer can be called out of RCU scope. | |
1000 | */ | |
1001 | if (tsk == current) | |
1002 | max_data->uid = current_uid(); | |
1003 | else | |
1004 | max_data->uid = task_uid(tsk); | |
1005 | ||
8248ac05 SR |
1006 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
1007 | max_data->policy = tsk->policy; | |
1008 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
1009 | |
1010 | /* record this tasks comm */ | |
1011 | tracing_record_cmdline(tsk); | |
1012 | } | |
1013 | ||
4fcdae83 SR |
1014 | /** |
1015 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
1016 | * @tr: tracer | |
1017 | * @tsk: the task with the latency | |
1018 | * @cpu: The cpu that initiated the trace. | |
1019 | * | |
1020 | * Flip the buffers between the @tr and the max_tr and record information | |
1021 | * about which task was the cause of this latency. | |
1022 | */ | |
e309b41d | 1023 | void |
bc0c38d1 SR |
1024 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1025 | { | |
2721e72d | 1026 | struct ring_buffer *buf; |
bc0c38d1 | 1027 | |
2b6080f2 | 1028 | if (tr->stop_count) |
b8de7bd1 SR |
1029 | return; |
1030 | ||
4c11d7ae | 1031 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 1032 | |
45ad21ca | 1033 | if (!tr->allocated_snapshot) { |
debdd57f | 1034 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 1035 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 1036 | return; |
debdd57f | 1037 | } |
34600f0e | 1038 | |
0b9b12c1 | 1039 | arch_spin_lock(&tr->max_lock); |
3928a8a2 | 1040 | |
12883efb SRRH |
1041 | buf = tr->trace_buffer.buffer; |
1042 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
1043 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 1044 | |
bc0c38d1 | 1045 | __update_max_tr(tr, tsk, cpu); |
0b9b12c1 | 1046 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 SR |
1047 | } |
1048 | ||
1049 | /** | |
1050 | * update_max_tr_single - only copy one trace over, and reset the rest | |
1051 | * @tr - tracer | |
1052 | * @tsk - task with the latency | |
1053 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
1054 | * |
1055 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1056 | */ |
e309b41d | 1057 | void |
bc0c38d1 SR |
1058 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1059 | { | |
3928a8a2 | 1060 | int ret; |
bc0c38d1 | 1061 | |
2b6080f2 | 1062 | if (tr->stop_count) |
b8de7bd1 SR |
1063 | return; |
1064 | ||
4c11d7ae | 1065 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1066 | if (!tr->allocated_snapshot) { |
2930e04d | 1067 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1068 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1069 | return; |
2930e04d | 1070 | } |
ef710e10 | 1071 | |
0b9b12c1 | 1072 | arch_spin_lock(&tr->max_lock); |
bc0c38d1 | 1073 | |
12883efb | 1074 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 1075 | |
e8165dbb SR |
1076 | if (ret == -EBUSY) { |
1077 | /* | |
1078 | * We failed to swap the buffer due to a commit taking | |
1079 | * place on this CPU. We fail to record, but we reset | |
1080 | * the max trace buffer (no one writes directly to it) | |
1081 | * and flag that it failed. | |
1082 | */ | |
12883efb | 1083 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1084 | "Failed to swap buffers due to commit in progress\n"); |
1085 | } | |
1086 | ||
e8165dbb | 1087 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1088 | |
1089 | __update_max_tr(tr, tsk, cpu); | |
0b9b12c1 | 1090 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 | 1091 | } |
5d4a9dba | 1092 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1093 | |
e30f53aa | 1094 | static int wait_on_pipe(struct trace_iterator *iter, bool full) |
0d5c6e1c | 1095 | { |
15693458 SRRH |
1096 | /* Iterators are static, they should be filled or empty */ |
1097 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
8b8b3683 | 1098 | return 0; |
0d5c6e1c | 1099 | |
e30f53aa RV |
1100 | return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file, |
1101 | full); | |
0d5c6e1c SR |
1102 | } |
1103 | ||
f4e781c0 SRRH |
1104 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
1105 | static int run_tracer_selftest(struct tracer *type) | |
1106 | { | |
1107 | struct trace_array *tr = &global_trace; | |
1108 | struct tracer *saved_tracer = tr->current_trace; | |
1109 | int ret; | |
0d5c6e1c | 1110 | |
f4e781c0 SRRH |
1111 | if (!type->selftest || tracing_selftest_disabled) |
1112 | return 0; | |
0d5c6e1c SR |
1113 | |
1114 | /* | |
f4e781c0 SRRH |
1115 | * Run a selftest on this tracer. |
1116 | * Here we reset the trace buffer, and set the current | |
1117 | * tracer to be this tracer. The tracer can then run some | |
1118 | * internal tracing to verify that everything is in order. | |
1119 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1120 | */ |
f4e781c0 | 1121 | tracing_reset_online_cpus(&tr->trace_buffer); |
0d5c6e1c | 1122 | |
f4e781c0 SRRH |
1123 | tr->current_trace = type; |
1124 | ||
1125 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1126 | if (type->use_max_tr) { | |
1127 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1128 | if (ring_buffer_expanded) | |
1129 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1130 | RING_BUFFER_ALL_CPUS); | |
1131 | tr->allocated_snapshot = true; | |
1132 | } | |
1133 | #endif | |
1134 | ||
1135 | /* the test is responsible for initializing and enabling */ | |
1136 | pr_info("Testing tracer %s: ", type->name); | |
1137 | ret = type->selftest(type, tr); | |
1138 | /* the test is responsible for resetting too */ | |
1139 | tr->current_trace = saved_tracer; | |
1140 | if (ret) { | |
1141 | printk(KERN_CONT "FAILED!\n"); | |
1142 | /* Add the warning after printing 'FAILED' */ | |
1143 | WARN_ON(1); | |
1144 | return -1; | |
1145 | } | |
1146 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1147 | tracing_reset_online_cpus(&tr->trace_buffer); | |
1148 | ||
1149 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1150 | if (type->use_max_tr) { | |
1151 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1152 | |
f4e781c0 SRRH |
1153 | /* Shrink the max buffer again */ |
1154 | if (ring_buffer_expanded) | |
1155 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1156 | RING_BUFFER_ALL_CPUS); | |
1157 | } | |
1158 | #endif | |
1159 | ||
1160 | printk(KERN_CONT "PASSED\n"); | |
1161 | return 0; | |
1162 | } | |
1163 | #else | |
1164 | static inline int run_tracer_selftest(struct tracer *type) | |
1165 | { | |
1166 | return 0; | |
0d5c6e1c | 1167 | } |
f4e781c0 | 1168 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 1169 | |
4fcdae83 SR |
1170 | /** |
1171 | * register_tracer - register a tracer with the ftrace system. | |
1172 | * @type - the plugin for the tracer | |
1173 | * | |
1174 | * Register a new plugin tracer. | |
1175 | */ | |
bc0c38d1 SR |
1176 | int register_tracer(struct tracer *type) |
1177 | { | |
1178 | struct tracer *t; | |
bc0c38d1 SR |
1179 | int ret = 0; |
1180 | ||
1181 | if (!type->name) { | |
1182 | pr_info("Tracer must have a name\n"); | |
1183 | return -1; | |
1184 | } | |
1185 | ||
24a461d5 | 1186 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
1187 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
1188 | return -1; | |
1189 | } | |
1190 | ||
bc0c38d1 | 1191 | mutex_lock(&trace_types_lock); |
86fa2f60 | 1192 | |
8e1b82e0 FW |
1193 | tracing_selftest_running = true; |
1194 | ||
bc0c38d1 SR |
1195 | for (t = trace_types; t; t = t->next) { |
1196 | if (strcmp(type->name, t->name) == 0) { | |
1197 | /* already found */ | |
ee6c2c1b | 1198 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
1199 | type->name); |
1200 | ret = -1; | |
1201 | goto out; | |
1202 | } | |
1203 | } | |
1204 | ||
adf9f195 FW |
1205 | if (!type->set_flag) |
1206 | type->set_flag = &dummy_set_flag; | |
1207 | if (!type->flags) | |
1208 | type->flags = &dummy_tracer_flags; | |
1209 | else | |
1210 | if (!type->flags->opts) | |
1211 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 | 1212 | |
f4e781c0 SRRH |
1213 | ret = run_tracer_selftest(type); |
1214 | if (ret < 0) | |
1215 | goto out; | |
60a11774 | 1216 | |
bc0c38d1 SR |
1217 | type->next = trace_types; |
1218 | trace_types = type; | |
60a11774 | 1219 | |
bc0c38d1 | 1220 | out: |
8e1b82e0 | 1221 | tracing_selftest_running = false; |
bc0c38d1 SR |
1222 | mutex_unlock(&trace_types_lock); |
1223 | ||
dac74940 SR |
1224 | if (ret || !default_bootup_tracer) |
1225 | goto out_unlock; | |
1226 | ||
ee6c2c1b | 1227 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1228 | goto out_unlock; |
1229 | ||
1230 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1231 | /* Do we want this tracer to start on bootup? */ | |
607e2ea1 | 1232 | tracing_set_tracer(&global_trace, type->name); |
dac74940 SR |
1233 | default_bootup_tracer = NULL; |
1234 | /* disable other selftests, since this will break it. */ | |
55034cd6 | 1235 | tracing_selftest_disabled = true; |
b2821ae6 | 1236 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1237 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1238 | type->name); | |
b2821ae6 | 1239 | #endif |
b2821ae6 | 1240 | |
dac74940 | 1241 | out_unlock: |
bc0c38d1 SR |
1242 | return ret; |
1243 | } | |
1244 | ||
12883efb | 1245 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1246 | { |
12883efb | 1247 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1248 | |
a5416411 HT |
1249 | if (!buffer) |
1250 | return; | |
1251 | ||
f633903a SR |
1252 | ring_buffer_record_disable(buffer); |
1253 | ||
1254 | /* Make sure all commits have finished */ | |
1255 | synchronize_sched(); | |
68179686 | 1256 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1257 | |
1258 | ring_buffer_record_enable(buffer); | |
1259 | } | |
1260 | ||
12883efb | 1261 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1262 | { |
12883efb | 1263 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1264 | int cpu; |
1265 | ||
a5416411 HT |
1266 | if (!buffer) |
1267 | return; | |
1268 | ||
621968cd SR |
1269 | ring_buffer_record_disable(buffer); |
1270 | ||
1271 | /* Make sure all commits have finished */ | |
1272 | synchronize_sched(); | |
1273 | ||
9457158b | 1274 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 PE |
1275 | |
1276 | for_each_online_cpu(cpu) | |
68179686 | 1277 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1278 | |
1279 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1280 | } |
1281 | ||
09d8091c | 1282 | /* Must have trace_types_lock held */ |
873c642f | 1283 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1284 | { |
873c642f SRRH |
1285 | struct trace_array *tr; |
1286 | ||
873c642f | 1287 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
12883efb SRRH |
1288 | tracing_reset_online_cpus(&tr->trace_buffer); |
1289 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1290 | tracing_reset_online_cpus(&tr->max_buffer); | |
1291 | #endif | |
873c642f | 1292 | } |
9456f0fa SR |
1293 | } |
1294 | ||
939c7a4f | 1295 | #define SAVED_CMDLINES_DEFAULT 128 |
2c7eea4c | 1296 | #define NO_CMDLINE_MAP UINT_MAX |
edc35bd7 | 1297 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
939c7a4f YY |
1298 | struct saved_cmdlines_buffer { |
1299 | unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
1300 | unsigned *map_cmdline_to_pid; | |
1301 | unsigned cmdline_num; | |
1302 | int cmdline_idx; | |
1303 | char *saved_cmdlines; | |
1304 | }; | |
1305 | static struct saved_cmdlines_buffer *savedcmd; | |
25b0b44a | 1306 | |
25b0b44a | 1307 | /* temporary disable recording */ |
4fd27358 | 1308 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 | 1309 | |
939c7a4f YY |
1310 | static inline char *get_saved_cmdlines(int idx) |
1311 | { | |
1312 | return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN]; | |
1313 | } | |
1314 | ||
1315 | static inline void set_cmdline(int idx, const char *cmdline) | |
bc0c38d1 | 1316 | { |
939c7a4f YY |
1317 | memcpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); |
1318 | } | |
1319 | ||
1320 | static int allocate_cmdlines_buffer(unsigned int val, | |
1321 | struct saved_cmdlines_buffer *s) | |
1322 | { | |
1323 | s->map_cmdline_to_pid = kmalloc(val * sizeof(*s->map_cmdline_to_pid), | |
1324 | GFP_KERNEL); | |
1325 | if (!s->map_cmdline_to_pid) | |
1326 | return -ENOMEM; | |
1327 | ||
1328 | s->saved_cmdlines = kmalloc(val * TASK_COMM_LEN, GFP_KERNEL); | |
1329 | if (!s->saved_cmdlines) { | |
1330 | kfree(s->map_cmdline_to_pid); | |
1331 | return -ENOMEM; | |
1332 | } | |
1333 | ||
1334 | s->cmdline_idx = 0; | |
1335 | s->cmdline_num = val; | |
1336 | memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP, | |
1337 | sizeof(s->map_pid_to_cmdline)); | |
1338 | memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP, | |
1339 | val * sizeof(*s->map_cmdline_to_pid)); | |
1340 | ||
1341 | return 0; | |
1342 | } | |
1343 | ||
1344 | static int trace_create_savedcmd(void) | |
1345 | { | |
1346 | int ret; | |
1347 | ||
a6af8fbf | 1348 | savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL); |
939c7a4f YY |
1349 | if (!savedcmd) |
1350 | return -ENOMEM; | |
1351 | ||
1352 | ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd); | |
1353 | if (ret < 0) { | |
1354 | kfree(savedcmd); | |
1355 | savedcmd = NULL; | |
1356 | return -ENOMEM; | |
1357 | } | |
1358 | ||
1359 | return 0; | |
bc0c38d1 SR |
1360 | } |
1361 | ||
b5130b1e CE |
1362 | int is_tracing_stopped(void) |
1363 | { | |
2b6080f2 | 1364 | return global_trace.stop_count; |
b5130b1e CE |
1365 | } |
1366 | ||
0f048701 SR |
1367 | /** |
1368 | * tracing_start - quick start of the tracer | |
1369 | * | |
1370 | * If tracing is enabled but was stopped by tracing_stop, | |
1371 | * this will start the tracer back up. | |
1372 | */ | |
1373 | void tracing_start(void) | |
1374 | { | |
1375 | struct ring_buffer *buffer; | |
1376 | unsigned long flags; | |
1377 | ||
1378 | if (tracing_disabled) | |
1379 | return; | |
1380 | ||
2b6080f2 SR |
1381 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1382 | if (--global_trace.stop_count) { | |
1383 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1384 | /* Someone screwed up their debugging */ |
1385 | WARN_ON_ONCE(1); | |
2b6080f2 | 1386 | global_trace.stop_count = 0; |
b06a8301 | 1387 | } |
0f048701 SR |
1388 | goto out; |
1389 | } | |
1390 | ||
a2f80714 | 1391 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1392 | arch_spin_lock(&global_trace.max_lock); |
0f048701 | 1393 | |
12883efb | 1394 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1395 | if (buffer) |
1396 | ring_buffer_record_enable(buffer); | |
1397 | ||
12883efb SRRH |
1398 | #ifdef CONFIG_TRACER_MAX_TRACE |
1399 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1400 | if (buffer) |
1401 | ring_buffer_record_enable(buffer); | |
12883efb | 1402 | #endif |
0f048701 | 1403 | |
0b9b12c1 | 1404 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1405 | |
0f048701 | 1406 | out: |
2b6080f2 SR |
1407 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1408 | } | |
1409 | ||
1410 | static void tracing_start_tr(struct trace_array *tr) | |
1411 | { | |
1412 | struct ring_buffer *buffer; | |
1413 | unsigned long flags; | |
1414 | ||
1415 | if (tracing_disabled) | |
1416 | return; | |
1417 | ||
1418 | /* If global, we need to also start the max tracer */ | |
1419 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1420 | return tracing_start(); | |
1421 | ||
1422 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1423 | ||
1424 | if (--tr->stop_count) { | |
1425 | if (tr->stop_count < 0) { | |
1426 | /* Someone screwed up their debugging */ | |
1427 | WARN_ON_ONCE(1); | |
1428 | tr->stop_count = 0; | |
1429 | } | |
1430 | goto out; | |
1431 | } | |
1432 | ||
12883efb | 1433 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1434 | if (buffer) |
1435 | ring_buffer_record_enable(buffer); | |
1436 | ||
1437 | out: | |
1438 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1439 | } |
1440 | ||
1441 | /** | |
1442 | * tracing_stop - quick stop of the tracer | |
1443 | * | |
1444 | * Light weight way to stop tracing. Use in conjunction with | |
1445 | * tracing_start. | |
1446 | */ | |
1447 | void tracing_stop(void) | |
1448 | { | |
1449 | struct ring_buffer *buffer; | |
1450 | unsigned long flags; | |
1451 | ||
2b6080f2 SR |
1452 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1453 | if (global_trace.stop_count++) | |
0f048701 SR |
1454 | goto out; |
1455 | ||
a2f80714 | 1456 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1457 | arch_spin_lock(&global_trace.max_lock); |
a2f80714 | 1458 | |
12883efb | 1459 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1460 | if (buffer) |
1461 | ring_buffer_record_disable(buffer); | |
1462 | ||
12883efb SRRH |
1463 | #ifdef CONFIG_TRACER_MAX_TRACE |
1464 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1465 | if (buffer) |
1466 | ring_buffer_record_disable(buffer); | |
12883efb | 1467 | #endif |
0f048701 | 1468 | |
0b9b12c1 | 1469 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1470 | |
0f048701 | 1471 | out: |
2b6080f2 SR |
1472 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1473 | } | |
1474 | ||
1475 | static void tracing_stop_tr(struct trace_array *tr) | |
1476 | { | |
1477 | struct ring_buffer *buffer; | |
1478 | unsigned long flags; | |
1479 | ||
1480 | /* If global, we need to also stop the max tracer */ | |
1481 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1482 | return tracing_stop(); | |
1483 | ||
1484 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1485 | if (tr->stop_count++) | |
1486 | goto out; | |
1487 | ||
12883efb | 1488 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1489 | if (buffer) |
1490 | ring_buffer_record_disable(buffer); | |
1491 | ||
1492 | out: | |
1493 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1494 | } |
1495 | ||
e309b41d | 1496 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1497 | |
379cfdac | 1498 | static int trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1499 | { |
a635cf04 | 1500 | unsigned pid, idx; |
bc0c38d1 SR |
1501 | |
1502 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
379cfdac | 1503 | return 0; |
bc0c38d1 SR |
1504 | |
1505 | /* | |
1506 | * It's not the end of the world if we don't get | |
1507 | * the lock, but we also don't want to spin | |
1508 | * nor do we want to disable interrupts, | |
1509 | * so if we miss here, then better luck next time. | |
1510 | */ | |
0199c4e6 | 1511 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
379cfdac | 1512 | return 0; |
bc0c38d1 | 1513 | |
939c7a4f | 1514 | idx = savedcmd->map_pid_to_cmdline[tsk->pid]; |
2c7eea4c | 1515 | if (idx == NO_CMDLINE_MAP) { |
939c7a4f | 1516 | idx = (savedcmd->cmdline_idx + 1) % savedcmd->cmdline_num; |
bc0c38d1 | 1517 | |
a635cf04 CE |
1518 | /* |
1519 | * Check whether the cmdline buffer at idx has a pid | |
1520 | * mapped. We are going to overwrite that entry so we | |
1521 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1522 | * would read the new comm for the old pid. | |
1523 | */ | |
939c7a4f | 1524 | pid = savedcmd->map_cmdline_to_pid[idx]; |
a635cf04 | 1525 | if (pid != NO_CMDLINE_MAP) |
939c7a4f | 1526 | savedcmd->map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; |
bc0c38d1 | 1527 | |
939c7a4f YY |
1528 | savedcmd->map_cmdline_to_pid[idx] = tsk->pid; |
1529 | savedcmd->map_pid_to_cmdline[tsk->pid] = idx; | |
bc0c38d1 | 1530 | |
939c7a4f | 1531 | savedcmd->cmdline_idx = idx; |
bc0c38d1 SR |
1532 | } |
1533 | ||
939c7a4f | 1534 | set_cmdline(idx, tsk->comm); |
bc0c38d1 | 1535 | |
0199c4e6 | 1536 | arch_spin_unlock(&trace_cmdline_lock); |
379cfdac SRRH |
1537 | |
1538 | return 1; | |
bc0c38d1 SR |
1539 | } |
1540 | ||
4c27e756 | 1541 | static void __trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1542 | { |
bc0c38d1 SR |
1543 | unsigned map; |
1544 | ||
4ca53085 SR |
1545 | if (!pid) { |
1546 | strcpy(comm, "<idle>"); | |
1547 | return; | |
1548 | } | |
bc0c38d1 | 1549 | |
74bf4076 SR |
1550 | if (WARN_ON_ONCE(pid < 0)) { |
1551 | strcpy(comm, "<XXX>"); | |
1552 | return; | |
1553 | } | |
1554 | ||
4ca53085 SR |
1555 | if (pid > PID_MAX_DEFAULT) { |
1556 | strcpy(comm, "<...>"); | |
1557 | return; | |
1558 | } | |
bc0c38d1 | 1559 | |
939c7a4f | 1560 | map = savedcmd->map_pid_to_cmdline[pid]; |
50d88758 | 1561 | if (map != NO_CMDLINE_MAP) |
939c7a4f | 1562 | strcpy(comm, get_saved_cmdlines(map)); |
50d88758 TG |
1563 | else |
1564 | strcpy(comm, "<...>"); | |
4c27e756 SRRH |
1565 | } |
1566 | ||
1567 | void trace_find_cmdline(int pid, char comm[]) | |
1568 | { | |
1569 | preempt_disable(); | |
1570 | arch_spin_lock(&trace_cmdline_lock); | |
1571 | ||
1572 | __trace_find_cmdline(pid, comm); | |
bc0c38d1 | 1573 | |
0199c4e6 | 1574 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1575 | preempt_enable(); |
bc0c38d1 SR |
1576 | } |
1577 | ||
e309b41d | 1578 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1579 | { |
0fb9656d | 1580 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1581 | return; |
1582 | ||
7ffbd48d SR |
1583 | if (!__this_cpu_read(trace_cmdline_save)) |
1584 | return; | |
1585 | ||
379cfdac SRRH |
1586 | if (trace_save_cmdline(tsk)) |
1587 | __this_cpu_write(trace_cmdline_save, false); | |
bc0c38d1 SR |
1588 | } |
1589 | ||
45dcd8b8 | 1590 | void |
38697053 SR |
1591 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1592 | int pc) | |
bc0c38d1 SR |
1593 | { |
1594 | struct task_struct *tsk = current; | |
bc0c38d1 | 1595 | |
777e208d SR |
1596 | entry->preempt_count = pc & 0xff; |
1597 | entry->pid = (tsk) ? tsk->pid : 0; | |
1598 | entry->flags = | |
9244489a | 1599 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1600 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1601 | #else |
1602 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1603 | #endif | |
bc0c38d1 SR |
1604 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1605 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
e5137b50 PZ |
1606 | (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) | |
1607 | (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0); | |
bc0c38d1 | 1608 | } |
f413cdb8 | 1609 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1610 | |
e77405ad SR |
1611 | struct ring_buffer_event * |
1612 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1613 | int type, | |
1614 | unsigned long len, | |
1615 | unsigned long flags, int pc) | |
51a763dd ACM |
1616 | { |
1617 | struct ring_buffer_event *event; | |
1618 | ||
e77405ad | 1619 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1620 | if (event != NULL) { |
1621 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1622 | ||
1623 | tracing_generic_entry_update(ent, flags, pc); | |
1624 | ent->type = type; | |
1625 | } | |
1626 | ||
1627 | return event; | |
1628 | } | |
51a763dd | 1629 | |
7ffbd48d SR |
1630 | void |
1631 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1632 | { | |
1633 | __this_cpu_write(trace_cmdline_save, true); | |
1634 | ring_buffer_unlock_commit(buffer, event); | |
1635 | } | |
1636 | ||
e77405ad SR |
1637 | static inline void |
1638 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1639 | struct ring_buffer_event *event, | |
0d5c6e1c | 1640 | unsigned long flags, int pc) |
51a763dd | 1641 | { |
7ffbd48d | 1642 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1643 | |
e77405ad SR |
1644 | ftrace_trace_stack(buffer, flags, 6, pc); |
1645 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1646 | } |
1647 | ||
e77405ad SR |
1648 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1649 | struct ring_buffer_event *event, | |
1650 | unsigned long flags, int pc) | |
07edf712 | 1651 | { |
0d5c6e1c | 1652 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
51a763dd | 1653 | } |
0d5c6e1c | 1654 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1655 | |
2c4a33ab SRRH |
1656 | static struct ring_buffer *temp_buffer; |
1657 | ||
ccb469a1 SR |
1658 | struct ring_buffer_event * |
1659 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
1660 | struct ftrace_event_file *ftrace_file, | |
1661 | int type, unsigned long len, | |
1662 | unsigned long flags, int pc) | |
1663 | { | |
2c4a33ab SRRH |
1664 | struct ring_buffer_event *entry; |
1665 | ||
12883efb | 1666 | *current_rb = ftrace_file->tr->trace_buffer.buffer; |
2c4a33ab | 1667 | entry = trace_buffer_lock_reserve(*current_rb, |
ccb469a1 | 1668 | type, len, flags, pc); |
2c4a33ab SRRH |
1669 | /* |
1670 | * If tracing is off, but we have triggers enabled | |
1671 | * we still need to look at the event data. Use the temp_buffer | |
1672 | * to store the trace event for the tigger to use. It's recusive | |
1673 | * safe and will not be recorded anywhere. | |
1674 | */ | |
1675 | if (!entry && ftrace_file->flags & FTRACE_EVENT_FL_TRIGGER_COND) { | |
1676 | *current_rb = temp_buffer; | |
1677 | entry = trace_buffer_lock_reserve(*current_rb, | |
1678 | type, len, flags, pc); | |
1679 | } | |
1680 | return entry; | |
ccb469a1 SR |
1681 | } |
1682 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
1683 | ||
ef5580d0 | 1684 | struct ring_buffer_event * |
e77405ad SR |
1685 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1686 | int type, unsigned long len, | |
ef5580d0 SR |
1687 | unsigned long flags, int pc) |
1688 | { | |
12883efb | 1689 | *current_rb = global_trace.trace_buffer.buffer; |
e77405ad | 1690 | return trace_buffer_lock_reserve(*current_rb, |
ef5580d0 SR |
1691 | type, len, flags, pc); |
1692 | } | |
94487d6d | 1693 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1694 | |
e77405ad SR |
1695 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1696 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1697 | unsigned long flags, int pc) |
1698 | { | |
0d5c6e1c | 1699 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
07edf712 | 1700 | } |
94487d6d | 1701 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1702 | |
0d5c6e1c SR |
1703 | void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1704 | struct ring_buffer_event *event, | |
1705 | unsigned long flags, int pc, | |
1706 | struct pt_regs *regs) | |
1fd8df2c | 1707 | { |
7ffbd48d | 1708 | __buffer_unlock_commit(buffer, event); |
1fd8df2c MH |
1709 | |
1710 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1711 | ftrace_trace_userstack(buffer, flags, pc); | |
1712 | } | |
0d5c6e1c | 1713 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1714 | |
e77405ad SR |
1715 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1716 | struct ring_buffer_event *event) | |
77d9f465 | 1717 | { |
e77405ad | 1718 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1719 | } |
12acd473 | 1720 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1721 | |
e309b41d | 1722 | void |
7be42151 | 1723 | trace_function(struct trace_array *tr, |
38697053 SR |
1724 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1725 | int pc) | |
bc0c38d1 | 1726 | { |
e1112b4d | 1727 | struct ftrace_event_call *call = &event_function; |
12883efb | 1728 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 1729 | struct ring_buffer_event *event; |
777e208d | 1730 | struct ftrace_entry *entry; |
bc0c38d1 | 1731 | |
d769041f | 1732 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1733 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1734 | return; |
1735 | ||
e77405ad | 1736 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1737 | flags, pc); |
3928a8a2 SR |
1738 | if (!event) |
1739 | return; | |
1740 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1741 | entry->ip = ip; |
1742 | entry->parent_ip = parent_ip; | |
e1112b4d | 1743 | |
f306cc82 | 1744 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1745 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1746 | } |
1747 | ||
c0a0d0d3 | 1748 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1749 | |
1750 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1751 | struct ftrace_stack { | |
1752 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1753 | }; | |
1754 | ||
1755 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1756 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1757 | ||
e77405ad | 1758 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1759 | unsigned long flags, |
1fd8df2c | 1760 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1761 | { |
e1112b4d | 1762 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1763 | struct ring_buffer_event *event; |
777e208d | 1764 | struct stack_entry *entry; |
86387f7e | 1765 | struct stack_trace trace; |
4a9bd3f1 SR |
1766 | int use_stack; |
1767 | int size = FTRACE_STACK_ENTRIES; | |
1768 | ||
1769 | trace.nr_entries = 0; | |
1770 | trace.skip = skip; | |
1771 | ||
1772 | /* | |
1773 | * Since events can happen in NMIs there's no safe way to | |
1774 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1775 | * or NMI comes in, it will just have to use the default | |
1776 | * FTRACE_STACK_SIZE. | |
1777 | */ | |
1778 | preempt_disable_notrace(); | |
1779 | ||
82146529 | 1780 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
1781 | /* |
1782 | * We don't need any atomic variables, just a barrier. | |
1783 | * If an interrupt comes in, we don't care, because it would | |
1784 | * have exited and put the counter back to what we want. | |
1785 | * We just need a barrier to keep gcc from moving things | |
1786 | * around. | |
1787 | */ | |
1788 | barrier(); | |
1789 | if (use_stack == 1) { | |
bdffd893 | 1790 | trace.entries = this_cpu_ptr(ftrace_stack.calls); |
4a9bd3f1 SR |
1791 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; |
1792 | ||
1793 | if (regs) | |
1794 | save_stack_trace_regs(regs, &trace); | |
1795 | else | |
1796 | save_stack_trace(&trace); | |
1797 | ||
1798 | if (trace.nr_entries > size) | |
1799 | size = trace.nr_entries; | |
1800 | } else | |
1801 | /* From now on, use_stack is a boolean */ | |
1802 | use_stack = 0; | |
1803 | ||
1804 | size *= sizeof(unsigned long); | |
86387f7e | 1805 | |
e77405ad | 1806 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1807 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1808 | if (!event) |
4a9bd3f1 SR |
1809 | goto out; |
1810 | entry = ring_buffer_event_data(event); | |
86387f7e | 1811 | |
4a9bd3f1 SR |
1812 | memset(&entry->caller, 0, size); |
1813 | ||
1814 | if (use_stack) | |
1815 | memcpy(&entry->caller, trace.entries, | |
1816 | trace.nr_entries * sizeof(unsigned long)); | |
1817 | else { | |
1818 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1819 | trace.entries = entry->caller; | |
1820 | if (regs) | |
1821 | save_stack_trace_regs(regs, &trace); | |
1822 | else | |
1823 | save_stack_trace(&trace); | |
1824 | } | |
1825 | ||
1826 | entry->size = trace.nr_entries; | |
86387f7e | 1827 | |
f306cc82 | 1828 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1829 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1830 | |
1831 | out: | |
1832 | /* Again, don't let gcc optimize things here */ | |
1833 | barrier(); | |
82146529 | 1834 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
1835 | preempt_enable_notrace(); |
1836 | ||
f0a920d5 IM |
1837 | } |
1838 | ||
1fd8df2c MH |
1839 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1840 | int skip, int pc, struct pt_regs *regs) | |
1841 | { | |
1842 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1843 | return; | |
1844 | ||
1845 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1846 | } | |
1847 | ||
e77405ad SR |
1848 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1849 | int skip, int pc) | |
53614991 SR |
1850 | { |
1851 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1852 | return; | |
1853 | ||
1fd8df2c | 1854 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1855 | } |
1856 | ||
c0a0d0d3 FW |
1857 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1858 | int pc) | |
38697053 | 1859 | { |
12883efb | 1860 | __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); |
38697053 SR |
1861 | } |
1862 | ||
03889384 SR |
1863 | /** |
1864 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 1865 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 1866 | */ |
c142be8e | 1867 | void trace_dump_stack(int skip) |
03889384 SR |
1868 | { |
1869 | unsigned long flags; | |
1870 | ||
1871 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1872 | return; |
03889384 SR |
1873 | |
1874 | local_save_flags(flags); | |
1875 | ||
c142be8e SRRH |
1876 | /* |
1877 | * Skip 3 more, seems to get us at the caller of | |
1878 | * this function. | |
1879 | */ | |
1880 | skip += 3; | |
1881 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, | |
1882 | flags, skip, preempt_count(), NULL); | |
03889384 SR |
1883 | } |
1884 | ||
91e86e56 SR |
1885 | static DEFINE_PER_CPU(int, user_stack_count); |
1886 | ||
e77405ad SR |
1887 | void |
1888 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1889 | { |
e1112b4d | 1890 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1891 | struct ring_buffer_event *event; |
02b67518 TE |
1892 | struct userstack_entry *entry; |
1893 | struct stack_trace trace; | |
02b67518 TE |
1894 | |
1895 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1896 | return; | |
1897 | ||
b6345879 SR |
1898 | /* |
1899 | * NMIs can not handle page faults, even with fix ups. | |
1900 | * The save user stack can (and often does) fault. | |
1901 | */ | |
1902 | if (unlikely(in_nmi())) | |
1903 | return; | |
02b67518 | 1904 | |
91e86e56 SR |
1905 | /* |
1906 | * prevent recursion, since the user stack tracing may | |
1907 | * trigger other kernel events. | |
1908 | */ | |
1909 | preempt_disable(); | |
1910 | if (__this_cpu_read(user_stack_count)) | |
1911 | goto out; | |
1912 | ||
1913 | __this_cpu_inc(user_stack_count); | |
1914 | ||
e77405ad | 1915 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1916 | sizeof(*entry), flags, pc); |
02b67518 | 1917 | if (!event) |
1dbd1951 | 1918 | goto out_drop_count; |
02b67518 | 1919 | entry = ring_buffer_event_data(event); |
02b67518 | 1920 | |
48659d31 | 1921 | entry->tgid = current->tgid; |
02b67518 TE |
1922 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1923 | ||
1924 | trace.nr_entries = 0; | |
1925 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1926 | trace.skip = 0; | |
1927 | trace.entries = entry->caller; | |
1928 | ||
1929 | save_stack_trace_user(&trace); | |
f306cc82 | 1930 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1931 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1932 | |
1dbd1951 | 1933 | out_drop_count: |
91e86e56 | 1934 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1935 | out: |
1936 | preempt_enable(); | |
02b67518 TE |
1937 | } |
1938 | ||
4fd27358 HE |
1939 | #ifdef UNUSED |
1940 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1941 | { |
7be42151 | 1942 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1943 | } |
4fd27358 | 1944 | #endif /* UNUSED */ |
02b67518 | 1945 | |
c0a0d0d3 FW |
1946 | #endif /* CONFIG_STACKTRACE */ |
1947 | ||
07d777fe SR |
1948 | /* created for use with alloc_percpu */ |
1949 | struct trace_buffer_struct { | |
1950 | char buffer[TRACE_BUF_SIZE]; | |
1951 | }; | |
1952 | ||
1953 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1954 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1955 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1956 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1957 | ||
1958 | /* | |
1959 | * The buffer used is dependent on the context. There is a per cpu | |
1960 | * buffer for normal context, softirq contex, hard irq context and | |
1961 | * for NMI context. Thise allows for lockless recording. | |
1962 | * | |
1963 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1964 | */ | |
1965 | static char *get_trace_buf(void) | |
1966 | { | |
1967 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
1968 | |
1969 | /* | |
1970 | * If we have allocated per cpu buffers, then we do not | |
1971 | * need to do any locking. | |
1972 | */ | |
1973 | if (in_nmi()) | |
1974 | percpu_buffer = trace_percpu_nmi_buffer; | |
1975 | else if (in_irq()) | |
1976 | percpu_buffer = trace_percpu_irq_buffer; | |
1977 | else if (in_softirq()) | |
1978 | percpu_buffer = trace_percpu_sirq_buffer; | |
1979 | else | |
1980 | percpu_buffer = trace_percpu_buffer; | |
1981 | ||
1982 | if (!percpu_buffer) | |
1983 | return NULL; | |
1984 | ||
d8a0349c | 1985 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
1986 | } |
1987 | ||
1988 | static int alloc_percpu_trace_buffer(void) | |
1989 | { | |
1990 | struct trace_buffer_struct *buffers; | |
1991 | struct trace_buffer_struct *sirq_buffers; | |
1992 | struct trace_buffer_struct *irq_buffers; | |
1993 | struct trace_buffer_struct *nmi_buffers; | |
1994 | ||
1995 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1996 | if (!buffers) | |
1997 | goto err_warn; | |
1998 | ||
1999 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
2000 | if (!sirq_buffers) | |
2001 | goto err_sirq; | |
2002 | ||
2003 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
2004 | if (!irq_buffers) | |
2005 | goto err_irq; | |
2006 | ||
2007 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
2008 | if (!nmi_buffers) | |
2009 | goto err_nmi; | |
2010 | ||
2011 | trace_percpu_buffer = buffers; | |
2012 | trace_percpu_sirq_buffer = sirq_buffers; | |
2013 | trace_percpu_irq_buffer = irq_buffers; | |
2014 | trace_percpu_nmi_buffer = nmi_buffers; | |
2015 | ||
2016 | return 0; | |
2017 | ||
2018 | err_nmi: | |
2019 | free_percpu(irq_buffers); | |
2020 | err_irq: | |
2021 | free_percpu(sirq_buffers); | |
2022 | err_sirq: | |
2023 | free_percpu(buffers); | |
2024 | err_warn: | |
2025 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
2026 | return -ENOMEM; | |
2027 | } | |
2028 | ||
81698831 SR |
2029 | static int buffers_allocated; |
2030 | ||
07d777fe SR |
2031 | void trace_printk_init_buffers(void) |
2032 | { | |
07d777fe SR |
2033 | if (buffers_allocated) |
2034 | return; | |
2035 | ||
2036 | if (alloc_percpu_trace_buffer()) | |
2037 | return; | |
2038 | ||
2184db46 SR |
2039 | /* trace_printk() is for debug use only. Don't use it in production. */ |
2040 | ||
69a1c994 BP |
2041 | pr_warning("\n"); |
2042 | pr_warning("**********************************************************\n"); | |
2184db46 SR |
2043 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); |
2044 | pr_warning("** **\n"); | |
2045 | pr_warning("** trace_printk() being used. Allocating extra memory. **\n"); | |
2046 | pr_warning("** **\n"); | |
2047 | pr_warning("** This means that this is a DEBUG kernel and it is **\n"); | |
eff264ef | 2048 | pr_warning("** unsafe for production use. **\n"); |
2184db46 SR |
2049 | pr_warning("** **\n"); |
2050 | pr_warning("** If you see this message and you are not debugging **\n"); | |
2051 | pr_warning("** the kernel, report this immediately to your vendor! **\n"); | |
2052 | pr_warning("** **\n"); | |
2053 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
2054 | pr_warning("**********************************************************\n"); | |
07d777fe | 2055 | |
b382ede6 SR |
2056 | /* Expand the buffers to set size */ |
2057 | tracing_update_buffers(); | |
2058 | ||
07d777fe | 2059 | buffers_allocated = 1; |
81698831 SR |
2060 | |
2061 | /* | |
2062 | * trace_printk_init_buffers() can be called by modules. | |
2063 | * If that happens, then we need to start cmdline recording | |
2064 | * directly here. If the global_trace.buffer is already | |
2065 | * allocated here, then this was called by module code. | |
2066 | */ | |
12883efb | 2067 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
2068 | tracing_start_cmdline_record(); |
2069 | } | |
2070 | ||
2071 | void trace_printk_start_comm(void) | |
2072 | { | |
2073 | /* Start tracing comms if trace printk is set */ | |
2074 | if (!buffers_allocated) | |
2075 | return; | |
2076 | tracing_start_cmdline_record(); | |
2077 | } | |
2078 | ||
2079 | static void trace_printk_start_stop_comm(int enabled) | |
2080 | { | |
2081 | if (!buffers_allocated) | |
2082 | return; | |
2083 | ||
2084 | if (enabled) | |
2085 | tracing_start_cmdline_record(); | |
2086 | else | |
2087 | tracing_stop_cmdline_record(); | |
07d777fe SR |
2088 | } |
2089 | ||
769b0441 | 2090 | /** |
48ead020 | 2091 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
2092 | * |
2093 | */ | |
40ce74f1 | 2094 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 2095 | { |
e1112b4d | 2096 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 2097 | struct ring_buffer_event *event; |
e77405ad | 2098 | struct ring_buffer *buffer; |
769b0441 | 2099 | struct trace_array *tr = &global_trace; |
48ead020 | 2100 | struct bprint_entry *entry; |
769b0441 | 2101 | unsigned long flags; |
07d777fe SR |
2102 | char *tbuffer; |
2103 | int len = 0, size, pc; | |
769b0441 FW |
2104 | |
2105 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
2106 | return 0; | |
2107 | ||
2108 | /* Don't pollute graph traces with trace_vprintk internals */ | |
2109 | pause_graph_tracing(); | |
2110 | ||
2111 | pc = preempt_count(); | |
5168ae50 | 2112 | preempt_disable_notrace(); |
769b0441 | 2113 | |
07d777fe SR |
2114 | tbuffer = get_trace_buf(); |
2115 | if (!tbuffer) { | |
2116 | len = 0; | |
769b0441 | 2117 | goto out; |
07d777fe | 2118 | } |
769b0441 | 2119 | |
07d777fe | 2120 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 2121 | |
07d777fe SR |
2122 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
2123 | goto out; | |
769b0441 | 2124 | |
07d777fe | 2125 | local_save_flags(flags); |
769b0441 | 2126 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 2127 | buffer = tr->trace_buffer.buffer; |
e77405ad SR |
2128 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
2129 | flags, pc); | |
769b0441 | 2130 | if (!event) |
07d777fe | 2131 | goto out; |
769b0441 FW |
2132 | entry = ring_buffer_event_data(event); |
2133 | entry->ip = ip; | |
769b0441 FW |
2134 | entry->fmt = fmt; |
2135 | ||
07d777fe | 2136 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
f306cc82 | 2137 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2138 | __buffer_unlock_commit(buffer, event); |
d931369b SR |
2139 | ftrace_trace_stack(buffer, flags, 6, pc); |
2140 | } | |
769b0441 | 2141 | |
769b0441 | 2142 | out: |
5168ae50 | 2143 | preempt_enable_notrace(); |
769b0441 FW |
2144 | unpause_graph_tracing(); |
2145 | ||
2146 | return len; | |
2147 | } | |
48ead020 FW |
2148 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
2149 | ||
12883efb SRRH |
2150 | static int |
2151 | __trace_array_vprintk(struct ring_buffer *buffer, | |
2152 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 2153 | { |
e1112b4d | 2154 | struct ftrace_event_call *call = &event_print; |
48ead020 | 2155 | struct ring_buffer_event *event; |
07d777fe | 2156 | int len = 0, size, pc; |
48ead020 | 2157 | struct print_entry *entry; |
07d777fe SR |
2158 | unsigned long flags; |
2159 | char *tbuffer; | |
48ead020 FW |
2160 | |
2161 | if (tracing_disabled || tracing_selftest_running) | |
2162 | return 0; | |
2163 | ||
07d777fe SR |
2164 | /* Don't pollute graph traces with trace_vprintk internals */ |
2165 | pause_graph_tracing(); | |
2166 | ||
48ead020 FW |
2167 | pc = preempt_count(); |
2168 | preempt_disable_notrace(); | |
48ead020 | 2169 | |
07d777fe SR |
2170 | |
2171 | tbuffer = get_trace_buf(); | |
2172 | if (!tbuffer) { | |
2173 | len = 0; | |
48ead020 | 2174 | goto out; |
07d777fe | 2175 | } |
48ead020 | 2176 | |
3558a5ac | 2177 | len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
48ead020 | 2178 | |
07d777fe | 2179 | local_save_flags(flags); |
48ead020 | 2180 | size = sizeof(*entry) + len + 1; |
e77405ad | 2181 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
07d777fe | 2182 | flags, pc); |
48ead020 | 2183 | if (!event) |
07d777fe | 2184 | goto out; |
48ead020 | 2185 | entry = ring_buffer_event_data(event); |
c13d2f7c | 2186 | entry->ip = ip; |
48ead020 | 2187 | |
3558a5ac | 2188 | memcpy(&entry->buf, tbuffer, len + 1); |
f306cc82 | 2189 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2190 | __buffer_unlock_commit(buffer, event); |
07d777fe | 2191 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 2192 | } |
48ead020 FW |
2193 | out: |
2194 | preempt_enable_notrace(); | |
07d777fe | 2195 | unpause_graph_tracing(); |
48ead020 FW |
2196 | |
2197 | return len; | |
2198 | } | |
659372d3 | 2199 | |
12883efb SRRH |
2200 | int trace_array_vprintk(struct trace_array *tr, |
2201 | unsigned long ip, const char *fmt, va_list args) | |
2202 | { | |
2203 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
2204 | } | |
2205 | ||
2206 | int trace_array_printk(struct trace_array *tr, | |
2207 | unsigned long ip, const char *fmt, ...) | |
2208 | { | |
2209 | int ret; | |
2210 | va_list ap; | |
2211 | ||
2212 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2213 | return 0; | |
2214 | ||
2215 | va_start(ap, fmt); | |
2216 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
2217 | va_end(ap); | |
2218 | return ret; | |
2219 | } | |
2220 | ||
2221 | int trace_array_printk_buf(struct ring_buffer *buffer, | |
2222 | unsigned long ip, const char *fmt, ...) | |
2223 | { | |
2224 | int ret; | |
2225 | va_list ap; | |
2226 | ||
2227 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2228 | return 0; | |
2229 | ||
2230 | va_start(ap, fmt); | |
2231 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
2232 | va_end(ap); | |
2233 | return ret; | |
2234 | } | |
2235 | ||
659372d3 SR |
2236 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
2237 | { | |
a813a159 | 2238 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 2239 | } |
769b0441 FW |
2240 | EXPORT_SYMBOL_GPL(trace_vprintk); |
2241 | ||
e2ac8ef5 | 2242 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 2243 | { |
6d158a81 SR |
2244 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
2245 | ||
5a90f577 | 2246 | iter->idx++; |
6d158a81 SR |
2247 | if (buf_iter) |
2248 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
2249 | } |
2250 | ||
e309b41d | 2251 | static struct trace_entry * |
bc21b478 SR |
2252 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
2253 | unsigned long *lost_events) | |
dd0e545f | 2254 | { |
3928a8a2 | 2255 | struct ring_buffer_event *event; |
6d158a81 | 2256 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 2257 | |
d769041f SR |
2258 | if (buf_iter) |
2259 | event = ring_buffer_iter_peek(buf_iter, ts); | |
2260 | else | |
12883efb | 2261 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 2262 | lost_events); |
d769041f | 2263 | |
4a9bd3f1 SR |
2264 | if (event) { |
2265 | iter->ent_size = ring_buffer_event_length(event); | |
2266 | return ring_buffer_event_data(event); | |
2267 | } | |
2268 | iter->ent_size = 0; | |
2269 | return NULL; | |
dd0e545f | 2270 | } |
d769041f | 2271 | |
dd0e545f | 2272 | static struct trace_entry * |
bc21b478 SR |
2273 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
2274 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 2275 | { |
12883efb | 2276 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 2277 | struct trace_entry *ent, *next = NULL; |
aa27497c | 2278 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 2279 | int cpu_file = iter->cpu_file; |
3928a8a2 | 2280 | u64 next_ts = 0, ts; |
bc0c38d1 | 2281 | int next_cpu = -1; |
12b5da34 | 2282 | int next_size = 0; |
bc0c38d1 SR |
2283 | int cpu; |
2284 | ||
b04cc6b1 FW |
2285 | /* |
2286 | * If we are in a per_cpu trace file, don't bother by iterating over | |
2287 | * all cpu and peek directly. | |
2288 | */ | |
ae3b5093 | 2289 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
2290 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
2291 | return NULL; | |
bc21b478 | 2292 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
2293 | if (ent_cpu) |
2294 | *ent_cpu = cpu_file; | |
2295 | ||
2296 | return ent; | |
2297 | } | |
2298 | ||
ab46428c | 2299 | for_each_tracing_cpu(cpu) { |
dd0e545f | 2300 | |
3928a8a2 SR |
2301 | if (ring_buffer_empty_cpu(buffer, cpu)) |
2302 | continue; | |
dd0e545f | 2303 | |
bc21b478 | 2304 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 2305 | |
cdd31cd2 IM |
2306 | /* |
2307 | * Pick the entry with the smallest timestamp: | |
2308 | */ | |
3928a8a2 | 2309 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
2310 | next = ent; |
2311 | next_cpu = cpu; | |
3928a8a2 | 2312 | next_ts = ts; |
bc21b478 | 2313 | next_lost = lost_events; |
12b5da34 | 2314 | next_size = iter->ent_size; |
bc0c38d1 SR |
2315 | } |
2316 | } | |
2317 | ||
12b5da34 SR |
2318 | iter->ent_size = next_size; |
2319 | ||
bc0c38d1 SR |
2320 | if (ent_cpu) |
2321 | *ent_cpu = next_cpu; | |
2322 | ||
3928a8a2 SR |
2323 | if (ent_ts) |
2324 | *ent_ts = next_ts; | |
2325 | ||
bc21b478 SR |
2326 | if (missing_events) |
2327 | *missing_events = next_lost; | |
2328 | ||
bc0c38d1 SR |
2329 | return next; |
2330 | } | |
2331 | ||
dd0e545f | 2332 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
2333 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
2334 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 2335 | { |
bc21b478 | 2336 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
2337 | } |
2338 | ||
2339 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 2340 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 2341 | { |
bc21b478 SR |
2342 | iter->ent = __find_next_entry(iter, &iter->cpu, |
2343 | &iter->lost_events, &iter->ts); | |
dd0e545f | 2344 | |
3928a8a2 | 2345 | if (iter->ent) |
e2ac8ef5 | 2346 | trace_iterator_increment(iter); |
dd0e545f | 2347 | |
3928a8a2 | 2348 | return iter->ent ? iter : NULL; |
b3806b43 | 2349 | } |
bc0c38d1 | 2350 | |
e309b41d | 2351 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 2352 | { |
12883efb | 2353 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 2354 | &iter->lost_events); |
bc0c38d1 SR |
2355 | } |
2356 | ||
e309b41d | 2357 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
2358 | { |
2359 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 2360 | int i = (int)*pos; |
4e3c3333 | 2361 | void *ent; |
bc0c38d1 | 2362 | |
a63ce5b3 SR |
2363 | WARN_ON_ONCE(iter->leftover); |
2364 | ||
bc0c38d1 SR |
2365 | (*pos)++; |
2366 | ||
2367 | /* can't go backwards */ | |
2368 | if (iter->idx > i) | |
2369 | return NULL; | |
2370 | ||
2371 | if (iter->idx < 0) | |
955b61e5 | 2372 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2373 | else |
2374 | ent = iter; | |
2375 | ||
2376 | while (ent && iter->idx < i) | |
955b61e5 | 2377 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2378 | |
2379 | iter->pos = *pos; | |
2380 | ||
bc0c38d1 SR |
2381 | return ent; |
2382 | } | |
2383 | ||
955b61e5 | 2384 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 2385 | { |
2f26ebd5 SR |
2386 | struct ring_buffer_event *event; |
2387 | struct ring_buffer_iter *buf_iter; | |
2388 | unsigned long entries = 0; | |
2389 | u64 ts; | |
2390 | ||
12883efb | 2391 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 2392 | |
6d158a81 SR |
2393 | buf_iter = trace_buffer_iter(iter, cpu); |
2394 | if (!buf_iter) | |
2f26ebd5 SR |
2395 | return; |
2396 | ||
2f26ebd5 SR |
2397 | ring_buffer_iter_reset(buf_iter); |
2398 | ||
2399 | /* | |
2400 | * We could have the case with the max latency tracers | |
2401 | * that a reset never took place on a cpu. This is evident | |
2402 | * by the timestamp being before the start of the buffer. | |
2403 | */ | |
2404 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 2405 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
2406 | break; |
2407 | entries++; | |
2408 | ring_buffer_read(buf_iter, NULL); | |
2409 | } | |
2410 | ||
12883efb | 2411 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2412 | } |
2413 | ||
d7350c3f | 2414 | /* |
d7350c3f FW |
2415 | * The current tracer is copied to avoid a global locking |
2416 | * all around. | |
2417 | */ | |
bc0c38d1 SR |
2418 | static void *s_start(struct seq_file *m, loff_t *pos) |
2419 | { | |
2420 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2421 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2422 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2423 | void *p = NULL; |
2424 | loff_t l = 0; | |
3928a8a2 | 2425 | int cpu; |
bc0c38d1 | 2426 | |
2fd196ec HT |
2427 | /* |
2428 | * copy the tracer to avoid using a global lock all around. | |
2429 | * iter->trace is a copy of current_trace, the pointer to the | |
2430 | * name may be used instead of a strcmp(), as iter->trace->name | |
2431 | * will point to the same string as current_trace->name. | |
2432 | */ | |
bc0c38d1 | 2433 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2434 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2435 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2436 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2437 | |
12883efb | 2438 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2439 | if (iter->snapshot && iter->trace->use_max_tr) |
2440 | return ERR_PTR(-EBUSY); | |
12883efb | 2441 | #endif |
debdd57f HT |
2442 | |
2443 | if (!iter->snapshot) | |
2444 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2445 | |
bc0c38d1 SR |
2446 | if (*pos != iter->pos) { |
2447 | iter->ent = NULL; | |
2448 | iter->cpu = 0; | |
2449 | iter->idx = -1; | |
2450 | ||
ae3b5093 | 2451 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2452 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2453 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2454 | } else |
2f26ebd5 | 2455 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2456 | |
ac91d854 | 2457 | iter->leftover = 0; |
bc0c38d1 SR |
2458 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2459 | ; | |
2460 | ||
2461 | } else { | |
a63ce5b3 SR |
2462 | /* |
2463 | * If we overflowed the seq_file before, then we want | |
2464 | * to just reuse the trace_seq buffer again. | |
2465 | */ | |
2466 | if (iter->leftover) | |
2467 | p = iter; | |
2468 | else { | |
2469 | l = *pos - 1; | |
2470 | p = s_next(m, p, &l); | |
2471 | } | |
bc0c38d1 SR |
2472 | } |
2473 | ||
4f535968 | 2474 | trace_event_read_lock(); |
7e53bd42 | 2475 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2476 | return p; |
2477 | } | |
2478 | ||
2479 | static void s_stop(struct seq_file *m, void *p) | |
2480 | { | |
7e53bd42 LJ |
2481 | struct trace_iterator *iter = m->private; |
2482 | ||
12883efb | 2483 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2484 | if (iter->snapshot && iter->trace->use_max_tr) |
2485 | return; | |
12883efb | 2486 | #endif |
debdd57f HT |
2487 | |
2488 | if (!iter->snapshot) | |
2489 | atomic_dec(&trace_record_cmdline_disabled); | |
12883efb | 2490 | |
7e53bd42 | 2491 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2492 | trace_event_read_unlock(); |
bc0c38d1 SR |
2493 | } |
2494 | ||
39eaf7ef | 2495 | static void |
12883efb SRRH |
2496 | get_total_entries(struct trace_buffer *buf, |
2497 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
2498 | { |
2499 | unsigned long count; | |
2500 | int cpu; | |
2501 | ||
2502 | *total = 0; | |
2503 | *entries = 0; | |
2504 | ||
2505 | for_each_tracing_cpu(cpu) { | |
12883efb | 2506 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2507 | /* |
2508 | * If this buffer has skipped entries, then we hold all | |
2509 | * entries for the trace and we need to ignore the | |
2510 | * ones before the time stamp. | |
2511 | */ | |
12883efb SRRH |
2512 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
2513 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2514 | /* total is the same as the entries */ |
2515 | *total += count; | |
2516 | } else | |
2517 | *total += count + | |
12883efb | 2518 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2519 | *entries += count; |
2520 | } | |
2521 | } | |
2522 | ||
e309b41d | 2523 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2524 | { |
d79ac28f RV |
2525 | seq_puts(m, "# _------=> CPU# \n" |
2526 | "# / _-----=> irqs-off \n" | |
2527 | "# | / _----=> need-resched \n" | |
2528 | "# || / _---=> hardirq/softirq \n" | |
2529 | "# ||| / _--=> preempt-depth \n" | |
2530 | "# |||| / delay \n" | |
2531 | "# cmd pid ||||| time | caller \n" | |
2532 | "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2533 | } |
2534 | ||
12883efb | 2535 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 2536 | { |
39eaf7ef SR |
2537 | unsigned long total; |
2538 | unsigned long entries; | |
2539 | ||
12883efb | 2540 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
2541 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
2542 | entries, total, num_online_cpus()); | |
2543 | seq_puts(m, "#\n"); | |
2544 | } | |
2545 | ||
12883efb | 2546 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) |
39eaf7ef | 2547 | { |
12883efb | 2548 | print_event_info(buf, m); |
d79ac28f RV |
2549 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n" |
2550 | "# | | | | |\n"); | |
bc0c38d1 SR |
2551 | } |
2552 | ||
12883efb | 2553 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) |
77271ce4 | 2554 | { |
12883efb | 2555 | print_event_info(buf, m); |
d79ac28f RV |
2556 | seq_puts(m, "# _-----=> irqs-off\n" |
2557 | "# / _----=> need-resched\n" | |
2558 | "# | / _---=> hardirq/softirq\n" | |
2559 | "# || / _--=> preempt-depth\n" | |
2560 | "# ||| / delay\n" | |
2561 | "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n" | |
2562 | "# | | | |||| | |\n"); | |
77271ce4 | 2563 | } |
bc0c38d1 | 2564 | |
62b915f1 | 2565 | void |
bc0c38d1 SR |
2566 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2567 | { | |
2568 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
12883efb SRRH |
2569 | struct trace_buffer *buf = iter->trace_buffer; |
2570 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 2571 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2572 | unsigned long entries; |
2573 | unsigned long total; | |
bc0c38d1 SR |
2574 | const char *name = "preemption"; |
2575 | ||
d840f718 | 2576 | name = type->name; |
bc0c38d1 | 2577 | |
12883efb | 2578 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 2579 | |
888b55dc | 2580 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2581 | name, UTS_RELEASE); |
888b55dc | 2582 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2583 | "---------------------------------\n"); |
888b55dc | 2584 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2585 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2586 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2587 | entries, |
4c11d7ae | 2588 | total, |
12883efb | 2589 | buf->cpu, |
bc0c38d1 SR |
2590 | #if defined(CONFIG_PREEMPT_NONE) |
2591 | "server", | |
2592 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2593 | "desktop", | |
b5c21b45 | 2594 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2595 | "preempt", |
2596 | #else | |
2597 | "unknown", | |
2598 | #endif | |
2599 | /* These are reserved for later use */ | |
2600 | 0, 0, 0, 0); | |
2601 | #ifdef CONFIG_SMP | |
2602 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2603 | #else | |
2604 | seq_puts(m, ")\n"); | |
2605 | #endif | |
888b55dc KM |
2606 | seq_puts(m, "# -----------------\n"); |
2607 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2608 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2609 | data->comm, data->pid, |
2610 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2611 | data->policy, data->rt_priority); |
888b55dc | 2612 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2613 | |
2614 | if (data->critical_start) { | |
888b55dc | 2615 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2616 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2617 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2618 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2619 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2620 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2621 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2622 | } |
2623 | ||
888b55dc | 2624 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2625 | } |
2626 | ||
a309720c SR |
2627 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2628 | { | |
2629 | struct trace_seq *s = &iter->seq; | |
2630 | ||
12ef7d44 SR |
2631 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2632 | return; | |
2633 | ||
2634 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2635 | return; | |
2636 | ||
4462344e | 2637 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2638 | return; |
2639 | ||
12883efb | 2640 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
2641 | return; |
2642 | ||
4462344e | 2643 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2644 | |
2645 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2646 | if (iter->idx > 1) | |
2647 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2648 | iter->cpu); | |
a309720c SR |
2649 | } |
2650 | ||
2c4f035f | 2651 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2652 | { |
214023c3 | 2653 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2654 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2655 | struct trace_entry *entry; |
f633cef0 | 2656 | struct trace_event *event; |
bc0c38d1 | 2657 | |
4e3c3333 | 2658 | entry = iter->ent; |
dd0e545f | 2659 | |
a309720c SR |
2660 | test_cpu_buff_start(iter); |
2661 | ||
c4a8e8be | 2662 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2663 | |
c4a8e8be | 2664 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
2665 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) |
2666 | trace_print_lat_context(iter); | |
2667 | else | |
2668 | trace_print_context(iter); | |
c4a8e8be | 2669 | } |
bc0c38d1 | 2670 | |
19a7fe20 SRRH |
2671 | if (trace_seq_has_overflowed(s)) |
2672 | return TRACE_TYPE_PARTIAL_LINE; | |
2673 | ||
268ccda0 | 2674 | if (event) |
a9a57763 | 2675 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 | 2676 | |
19a7fe20 | 2677 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
02b67518 | 2678 | |
19a7fe20 | 2679 | return trace_handle_return(s); |
bc0c38d1 SR |
2680 | } |
2681 | ||
2c4f035f | 2682 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2683 | { |
2684 | struct trace_seq *s = &iter->seq; | |
2685 | struct trace_entry *entry; | |
f633cef0 | 2686 | struct trace_event *event; |
f9896bf3 IM |
2687 | |
2688 | entry = iter->ent; | |
dd0e545f | 2689 | |
19a7fe20 SRRH |
2690 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) |
2691 | trace_seq_printf(s, "%d %d %llu ", | |
2692 | entry->pid, iter->cpu, iter->ts); | |
2693 | ||
2694 | if (trace_seq_has_overflowed(s)) | |
2695 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 | 2696 | |
f633cef0 | 2697 | event = ftrace_find_event(entry->type); |
268ccda0 | 2698 | if (event) |
a9a57763 | 2699 | return event->funcs->raw(iter, 0, event); |
d9793bd8 | 2700 | |
19a7fe20 | 2701 | trace_seq_printf(s, "%d ?\n", entry->type); |
777e208d | 2702 | |
19a7fe20 | 2703 | return trace_handle_return(s); |
f9896bf3 IM |
2704 | } |
2705 | ||
2c4f035f | 2706 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2707 | { |
2708 | struct trace_seq *s = &iter->seq; | |
2709 | unsigned char newline = '\n'; | |
2710 | struct trace_entry *entry; | |
f633cef0 | 2711 | struct trace_event *event; |
5e3ca0ec IM |
2712 | |
2713 | entry = iter->ent; | |
dd0e545f | 2714 | |
c4a8e8be | 2715 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
2716 | SEQ_PUT_HEX_FIELD(s, entry->pid); |
2717 | SEQ_PUT_HEX_FIELD(s, iter->cpu); | |
2718 | SEQ_PUT_HEX_FIELD(s, iter->ts); | |
2719 | if (trace_seq_has_overflowed(s)) | |
2720 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 2721 | } |
5e3ca0ec | 2722 | |
f633cef0 | 2723 | event = ftrace_find_event(entry->type); |
268ccda0 | 2724 | if (event) { |
a9a57763 | 2725 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2726 | if (ret != TRACE_TYPE_HANDLED) |
2727 | return ret; | |
2728 | } | |
7104f300 | 2729 | |
19a7fe20 | 2730 | SEQ_PUT_FIELD(s, newline); |
5e3ca0ec | 2731 | |
19a7fe20 | 2732 | return trace_handle_return(s); |
5e3ca0ec IM |
2733 | } |
2734 | ||
2c4f035f | 2735 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2736 | { |
2737 | struct trace_seq *s = &iter->seq; | |
2738 | struct trace_entry *entry; | |
f633cef0 | 2739 | struct trace_event *event; |
cb0f12aa IM |
2740 | |
2741 | entry = iter->ent; | |
dd0e545f | 2742 | |
c4a8e8be | 2743 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
2744 | SEQ_PUT_FIELD(s, entry->pid); |
2745 | SEQ_PUT_FIELD(s, iter->cpu); | |
2746 | SEQ_PUT_FIELD(s, iter->ts); | |
2747 | if (trace_seq_has_overflowed(s)) | |
2748 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 2749 | } |
cb0f12aa | 2750 | |
f633cef0 | 2751 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2752 | return event ? event->funcs->binary(iter, 0, event) : |
2753 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2754 | } |
2755 | ||
62b915f1 | 2756 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2757 | { |
6d158a81 | 2758 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2759 | int cpu; |
2760 | ||
9aba60fe | 2761 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 2762 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 2763 | cpu = iter->cpu_file; |
6d158a81 SR |
2764 | buf_iter = trace_buffer_iter(iter, cpu); |
2765 | if (buf_iter) { | |
2766 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2767 | return 0; |
2768 | } else { | |
12883efb | 2769 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
2770 | return 0; |
2771 | } | |
2772 | return 1; | |
2773 | } | |
2774 | ||
ab46428c | 2775 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2776 | buf_iter = trace_buffer_iter(iter, cpu); |
2777 | if (buf_iter) { | |
2778 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2779 | return 0; |
2780 | } else { | |
12883efb | 2781 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
2782 | return 0; |
2783 | } | |
bc0c38d1 | 2784 | } |
d769041f | 2785 | |
797d3712 | 2786 | return 1; |
bc0c38d1 SR |
2787 | } |
2788 | ||
4f535968 | 2789 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2790 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2791 | { |
2c4f035f FW |
2792 | enum print_line_t ret; |
2793 | ||
19a7fe20 SRRH |
2794 | if (iter->lost_events) { |
2795 | trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2796 | iter->cpu, iter->lost_events); | |
2797 | if (trace_seq_has_overflowed(&iter->seq)) | |
2798 | return TRACE_TYPE_PARTIAL_LINE; | |
2799 | } | |
bc21b478 | 2800 | |
2c4f035f FW |
2801 | if (iter->trace && iter->trace->print_line) { |
2802 | ret = iter->trace->print_line(iter); | |
2803 | if (ret != TRACE_TYPE_UNHANDLED) | |
2804 | return ret; | |
2805 | } | |
72829bc3 | 2806 | |
09ae7234 SRRH |
2807 | if (iter->ent->type == TRACE_BPUTS && |
2808 | trace_flags & TRACE_ITER_PRINTK && | |
2809 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
2810 | return trace_print_bputs_msg_only(iter); | |
2811 | ||
48ead020 FW |
2812 | if (iter->ent->type == TRACE_BPRINT && |
2813 | trace_flags & TRACE_ITER_PRINTK && | |
2814 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2815 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2816 | |
66896a85 FW |
2817 | if (iter->ent->type == TRACE_PRINT && |
2818 | trace_flags & TRACE_ITER_PRINTK && | |
2819 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2820 | return trace_print_printk_msg_only(iter); |
66896a85 | 2821 | |
cb0f12aa IM |
2822 | if (trace_flags & TRACE_ITER_BIN) |
2823 | return print_bin_fmt(iter); | |
2824 | ||
5e3ca0ec IM |
2825 | if (trace_flags & TRACE_ITER_HEX) |
2826 | return print_hex_fmt(iter); | |
2827 | ||
f9896bf3 IM |
2828 | if (trace_flags & TRACE_ITER_RAW) |
2829 | return print_raw_fmt(iter); | |
2830 | ||
f9896bf3 IM |
2831 | return print_trace_fmt(iter); |
2832 | } | |
2833 | ||
7e9a49ef JO |
2834 | void trace_latency_header(struct seq_file *m) |
2835 | { | |
2836 | struct trace_iterator *iter = m->private; | |
2837 | ||
2838 | /* print nothing if the buffers are empty */ | |
2839 | if (trace_empty(iter)) | |
2840 | return; | |
2841 | ||
2842 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2843 | print_trace_header(m, iter); | |
2844 | ||
2845 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2846 | print_lat_help_header(m); | |
2847 | } | |
2848 | ||
62b915f1 JO |
2849 | void trace_default_header(struct seq_file *m) |
2850 | { | |
2851 | struct trace_iterator *iter = m->private; | |
2852 | ||
f56e7f8e JO |
2853 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2854 | return; | |
2855 | ||
62b915f1 JO |
2856 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2857 | /* print nothing if the buffers are empty */ | |
2858 | if (trace_empty(iter)) | |
2859 | return; | |
2860 | print_trace_header(m, iter); | |
2861 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2862 | print_lat_help_header(m); | |
2863 | } else { | |
77271ce4 SR |
2864 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2865 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
12883efb | 2866 | print_func_help_header_irq(iter->trace_buffer, m); |
77271ce4 | 2867 | else |
12883efb | 2868 | print_func_help_header(iter->trace_buffer, m); |
77271ce4 | 2869 | } |
62b915f1 JO |
2870 | } |
2871 | } | |
2872 | ||
e0a413f6 SR |
2873 | static void test_ftrace_alive(struct seq_file *m) |
2874 | { | |
2875 | if (!ftrace_is_dead()) | |
2876 | return; | |
d79ac28f RV |
2877 | seq_puts(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n" |
2878 | "# MAY BE MISSING FUNCTION EVENTS\n"); | |
e0a413f6 SR |
2879 | } |
2880 | ||
d8741e2e | 2881 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 2882 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 2883 | { |
d79ac28f RV |
2884 | seq_puts(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n" |
2885 | "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" | |
2886 | "# Takes a snapshot of the main buffer.\n" | |
2887 | "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n" | |
2888 | "# (Doesn't have to be '2' works with any number that\n" | |
2889 | "# is not a '0' or '1')\n"); | |
d8741e2e | 2890 | } |
f1affcaa SRRH |
2891 | |
2892 | static void show_snapshot_percpu_help(struct seq_file *m) | |
2893 | { | |
fa6f0cc7 | 2894 | seq_puts(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); |
f1affcaa | 2895 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP |
d79ac28f RV |
2896 | seq_puts(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" |
2897 | "# Takes a snapshot of the main buffer for this cpu.\n"); | |
f1affcaa | 2898 | #else |
d79ac28f RV |
2899 | seq_puts(m, "# echo 1 > snapshot : Not supported with this kernel.\n" |
2900 | "# Must use main snapshot file to allocate.\n"); | |
f1affcaa | 2901 | #endif |
d79ac28f RV |
2902 | seq_puts(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n" |
2903 | "# (Doesn't have to be '2' works with any number that\n" | |
2904 | "# is not a '0' or '1')\n"); | |
f1affcaa SRRH |
2905 | } |
2906 | ||
d8741e2e SRRH |
2907 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
2908 | { | |
45ad21ca | 2909 | if (iter->tr->allocated_snapshot) |
fa6f0cc7 | 2910 | seq_puts(m, "#\n# * Snapshot is allocated *\n#\n"); |
d8741e2e | 2911 | else |
fa6f0cc7 | 2912 | seq_puts(m, "#\n# * Snapshot is freed *\n#\n"); |
d8741e2e | 2913 | |
fa6f0cc7 | 2914 | seq_puts(m, "# Snapshot commands:\n"); |
f1affcaa SRRH |
2915 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
2916 | show_snapshot_main_help(m); | |
2917 | else | |
2918 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
2919 | } |
2920 | #else | |
2921 | /* Should never be called */ | |
2922 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
2923 | #endif | |
2924 | ||
bc0c38d1 SR |
2925 | static int s_show(struct seq_file *m, void *v) |
2926 | { | |
2927 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2928 | int ret; |
bc0c38d1 SR |
2929 | |
2930 | if (iter->ent == NULL) { | |
2931 | if (iter->tr) { | |
2932 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2933 | seq_puts(m, "#\n"); | |
e0a413f6 | 2934 | test_ftrace_alive(m); |
bc0c38d1 | 2935 | } |
d8741e2e SRRH |
2936 | if (iter->snapshot && trace_empty(iter)) |
2937 | print_snapshot_help(m, iter); | |
2938 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 2939 | iter->trace->print_header(m); |
62b915f1 JO |
2940 | else |
2941 | trace_default_header(m); | |
2942 | ||
a63ce5b3 SR |
2943 | } else if (iter->leftover) { |
2944 | /* | |
2945 | * If we filled the seq_file buffer earlier, we | |
2946 | * want to just show it now. | |
2947 | */ | |
2948 | ret = trace_print_seq(m, &iter->seq); | |
2949 | ||
2950 | /* ret should this time be zero, but you never know */ | |
2951 | iter->leftover = ret; | |
2952 | ||
bc0c38d1 | 2953 | } else { |
f9896bf3 | 2954 | print_trace_line(iter); |
a63ce5b3 SR |
2955 | ret = trace_print_seq(m, &iter->seq); |
2956 | /* | |
2957 | * If we overflow the seq_file buffer, then it will | |
2958 | * ask us for this data again at start up. | |
2959 | * Use that instead. | |
2960 | * ret is 0 if seq_file write succeeded. | |
2961 | * -1 otherwise. | |
2962 | */ | |
2963 | iter->leftover = ret; | |
bc0c38d1 SR |
2964 | } |
2965 | ||
2966 | return 0; | |
2967 | } | |
2968 | ||
649e9c70 ON |
2969 | /* |
2970 | * Should be used after trace_array_get(), trace_types_lock | |
2971 | * ensures that i_cdev was already initialized. | |
2972 | */ | |
2973 | static inline int tracing_get_cpu(struct inode *inode) | |
2974 | { | |
2975 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
2976 | return (long)inode->i_cdev - 1; | |
2977 | return RING_BUFFER_ALL_CPUS; | |
2978 | } | |
2979 | ||
88e9d34c | 2980 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2981 | .start = s_start, |
2982 | .next = s_next, | |
2983 | .stop = s_stop, | |
2984 | .show = s_show, | |
bc0c38d1 SR |
2985 | }; |
2986 | ||
e309b41d | 2987 | static struct trace_iterator * |
6484c71c | 2988 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 2989 | { |
6484c71c | 2990 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 2991 | struct trace_iterator *iter; |
50e18b94 | 2992 | int cpu; |
bc0c38d1 | 2993 | |
85a2f9b4 SR |
2994 | if (tracing_disabled) |
2995 | return ERR_PTR(-ENODEV); | |
60a11774 | 2996 | |
50e18b94 | 2997 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2998 | if (!iter) |
2999 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 3000 | |
6d158a81 SR |
3001 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
3002 | GFP_KERNEL); | |
93574fcc DC |
3003 | if (!iter->buffer_iter) |
3004 | goto release; | |
3005 | ||
d7350c3f FW |
3006 | /* |
3007 | * We make a copy of the current tracer to avoid concurrent | |
3008 | * changes on it while we are reading. | |
3009 | */ | |
bc0c38d1 | 3010 | mutex_lock(&trace_types_lock); |
d7350c3f | 3011 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 3012 | if (!iter->trace) |
d7350c3f | 3013 | goto fail; |
85a2f9b4 | 3014 | |
2b6080f2 | 3015 | *iter->trace = *tr->current_trace; |
d7350c3f | 3016 | |
79f55997 | 3017 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
3018 | goto fail; |
3019 | ||
12883efb SRRH |
3020 | iter->tr = tr; |
3021 | ||
3022 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
3023 | /* Currently only the top directory has a snapshot */ |
3024 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 3025 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 3026 | else |
12883efb SRRH |
3027 | #endif |
3028 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 3029 | iter->snapshot = snapshot; |
bc0c38d1 | 3030 | iter->pos = -1; |
6484c71c | 3031 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 3032 | mutex_init(&iter->mutex); |
bc0c38d1 | 3033 | |
8bba1bf5 MM |
3034 | /* Notify the tracer early; before we stop tracing. */ |
3035 | if (iter->trace && iter->trace->open) | |
a93751ca | 3036 | iter->trace->open(iter); |
8bba1bf5 | 3037 | |
12ef7d44 | 3038 | /* Annotate start of buffers if we had overruns */ |
12883efb | 3039 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
3040 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
3041 | ||
8be0709f | 3042 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 3043 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
3044 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
3045 | ||
debdd57f HT |
3046 | /* stop the trace while dumping if we are not opening "snapshot" */ |
3047 | if (!iter->snapshot) | |
2b6080f2 | 3048 | tracing_stop_tr(tr); |
2f26ebd5 | 3049 | |
ae3b5093 | 3050 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 3051 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 3052 | iter->buffer_iter[cpu] = |
12883efb | 3053 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3054 | } |
3055 | ring_buffer_read_prepare_sync(); | |
3056 | for_each_tracing_cpu(cpu) { | |
3057 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3058 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
3059 | } |
3060 | } else { | |
3061 | cpu = iter->cpu_file; | |
3928a8a2 | 3062 | iter->buffer_iter[cpu] = |
12883efb | 3063 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3064 | ring_buffer_read_prepare_sync(); |
3065 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3066 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
3067 | } |
3068 | ||
bc0c38d1 SR |
3069 | mutex_unlock(&trace_types_lock); |
3070 | ||
bc0c38d1 | 3071 | return iter; |
3928a8a2 | 3072 | |
d7350c3f | 3073 | fail: |
3928a8a2 | 3074 | mutex_unlock(&trace_types_lock); |
d7350c3f | 3075 | kfree(iter->trace); |
6d158a81 | 3076 | kfree(iter->buffer_iter); |
93574fcc | 3077 | release: |
50e18b94 JO |
3078 | seq_release_private(inode, file); |
3079 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
3080 | } |
3081 | ||
3082 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
3083 | { | |
60a11774 SR |
3084 | if (tracing_disabled) |
3085 | return -ENODEV; | |
3086 | ||
bc0c38d1 SR |
3087 | filp->private_data = inode->i_private; |
3088 | return 0; | |
3089 | } | |
3090 | ||
2e86421d GB |
3091 | bool tracing_is_disabled(void) |
3092 | { | |
3093 | return (tracing_disabled) ? true: false; | |
3094 | } | |
3095 | ||
7b85af63 SRRH |
3096 | /* |
3097 | * Open and update trace_array ref count. | |
3098 | * Must have the current trace_array passed to it. | |
3099 | */ | |
dcc30223 | 3100 | static int tracing_open_generic_tr(struct inode *inode, struct file *filp) |
7b85af63 SRRH |
3101 | { |
3102 | struct trace_array *tr = inode->i_private; | |
3103 | ||
3104 | if (tracing_disabled) | |
3105 | return -ENODEV; | |
3106 | ||
3107 | if (trace_array_get(tr) < 0) | |
3108 | return -ENODEV; | |
3109 | ||
3110 | filp->private_data = inode->i_private; | |
3111 | ||
3112 | return 0; | |
7b85af63 SRRH |
3113 | } |
3114 | ||
4fd27358 | 3115 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 3116 | { |
6484c71c | 3117 | struct trace_array *tr = inode->i_private; |
907f2784 | 3118 | struct seq_file *m = file->private_data; |
4acd4d00 | 3119 | struct trace_iterator *iter; |
3928a8a2 | 3120 | int cpu; |
bc0c38d1 | 3121 | |
ff451961 | 3122 | if (!(file->f_mode & FMODE_READ)) { |
6484c71c | 3123 | trace_array_put(tr); |
4acd4d00 | 3124 | return 0; |
ff451961 | 3125 | } |
4acd4d00 | 3126 | |
6484c71c | 3127 | /* Writes do not use seq_file */ |
4acd4d00 | 3128 | iter = m->private; |
bc0c38d1 | 3129 | mutex_lock(&trace_types_lock); |
a695cb58 | 3130 | |
3928a8a2 SR |
3131 | for_each_tracing_cpu(cpu) { |
3132 | if (iter->buffer_iter[cpu]) | |
3133 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
3134 | } | |
3135 | ||
bc0c38d1 SR |
3136 | if (iter->trace && iter->trace->close) |
3137 | iter->trace->close(iter); | |
3138 | ||
debdd57f HT |
3139 | if (!iter->snapshot) |
3140 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 3141 | tracing_start_tr(tr); |
f77d09a3 AL |
3142 | |
3143 | __trace_array_put(tr); | |
3144 | ||
bc0c38d1 SR |
3145 | mutex_unlock(&trace_types_lock); |
3146 | ||
d7350c3f | 3147 | mutex_destroy(&iter->mutex); |
b0dfa978 | 3148 | free_cpumask_var(iter->started); |
d7350c3f | 3149 | kfree(iter->trace); |
6d158a81 | 3150 | kfree(iter->buffer_iter); |
50e18b94 | 3151 | seq_release_private(inode, file); |
ff451961 | 3152 | |
bc0c38d1 SR |
3153 | return 0; |
3154 | } | |
3155 | ||
7b85af63 SRRH |
3156 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
3157 | { | |
3158 | struct trace_array *tr = inode->i_private; | |
3159 | ||
3160 | trace_array_put(tr); | |
bc0c38d1 SR |
3161 | return 0; |
3162 | } | |
3163 | ||
7b85af63 SRRH |
3164 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
3165 | { | |
3166 | struct trace_array *tr = inode->i_private; | |
3167 | ||
3168 | trace_array_put(tr); | |
3169 | ||
3170 | return single_release(inode, file); | |
3171 | } | |
3172 | ||
bc0c38d1 SR |
3173 | static int tracing_open(struct inode *inode, struct file *file) |
3174 | { | |
6484c71c | 3175 | struct trace_array *tr = inode->i_private; |
85a2f9b4 SR |
3176 | struct trace_iterator *iter; |
3177 | int ret = 0; | |
bc0c38d1 | 3178 | |
ff451961 SRRH |
3179 | if (trace_array_get(tr) < 0) |
3180 | return -ENODEV; | |
3181 | ||
4acd4d00 | 3182 | /* If this file was open for write, then erase contents */ |
6484c71c ON |
3183 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
3184 | int cpu = tracing_get_cpu(inode); | |
3185 | ||
3186 | if (cpu == RING_BUFFER_ALL_CPUS) | |
12883efb | 3187 | tracing_reset_online_cpus(&tr->trace_buffer); |
4acd4d00 | 3188 | else |
6484c71c | 3189 | tracing_reset(&tr->trace_buffer, cpu); |
4acd4d00 | 3190 | } |
bc0c38d1 | 3191 | |
4acd4d00 | 3192 | if (file->f_mode & FMODE_READ) { |
6484c71c | 3193 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
3194 | if (IS_ERR(iter)) |
3195 | ret = PTR_ERR(iter); | |
3196 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
3197 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3198 | } | |
ff451961 SRRH |
3199 | |
3200 | if (ret < 0) | |
3201 | trace_array_put(tr); | |
3202 | ||
bc0c38d1 SR |
3203 | return ret; |
3204 | } | |
3205 | ||
607e2ea1 SRRH |
3206 | /* |
3207 | * Some tracers are not suitable for instance buffers. | |
3208 | * A tracer is always available for the global array (toplevel) | |
3209 | * or if it explicitly states that it is. | |
3210 | */ | |
3211 | static bool | |
3212 | trace_ok_for_array(struct tracer *t, struct trace_array *tr) | |
3213 | { | |
3214 | return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; | |
3215 | } | |
3216 | ||
3217 | /* Find the next tracer that this trace array may use */ | |
3218 | static struct tracer * | |
3219 | get_tracer_for_array(struct trace_array *tr, struct tracer *t) | |
3220 | { | |
3221 | while (t && !trace_ok_for_array(t, tr)) | |
3222 | t = t->next; | |
3223 | ||
3224 | return t; | |
3225 | } | |
3226 | ||
e309b41d | 3227 | static void * |
bc0c38d1 SR |
3228 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3229 | { | |
607e2ea1 | 3230 | struct trace_array *tr = m->private; |
f129e965 | 3231 | struct tracer *t = v; |
bc0c38d1 SR |
3232 | |
3233 | (*pos)++; | |
3234 | ||
3235 | if (t) | |
607e2ea1 | 3236 | t = get_tracer_for_array(tr, t->next); |
bc0c38d1 | 3237 | |
bc0c38d1 SR |
3238 | return t; |
3239 | } | |
3240 | ||
3241 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3242 | { | |
607e2ea1 | 3243 | struct trace_array *tr = m->private; |
f129e965 | 3244 | struct tracer *t; |
bc0c38d1 SR |
3245 | loff_t l = 0; |
3246 | ||
3247 | mutex_lock(&trace_types_lock); | |
607e2ea1 SRRH |
3248 | |
3249 | t = get_tracer_for_array(tr, trace_types); | |
3250 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
3251 | ; | |
bc0c38d1 SR |
3252 | |
3253 | return t; | |
3254 | } | |
3255 | ||
3256 | static void t_stop(struct seq_file *m, void *p) | |
3257 | { | |
3258 | mutex_unlock(&trace_types_lock); | |
3259 | } | |
3260 | ||
3261 | static int t_show(struct seq_file *m, void *v) | |
3262 | { | |
3263 | struct tracer *t = v; | |
3264 | ||
3265 | if (!t) | |
3266 | return 0; | |
3267 | ||
fa6f0cc7 | 3268 | seq_puts(m, t->name); |
bc0c38d1 SR |
3269 | if (t->next) |
3270 | seq_putc(m, ' '); | |
3271 | else | |
3272 | seq_putc(m, '\n'); | |
3273 | ||
3274 | return 0; | |
3275 | } | |
3276 | ||
88e9d34c | 3277 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
3278 | .start = t_start, |
3279 | .next = t_next, | |
3280 | .stop = t_stop, | |
3281 | .show = t_show, | |
bc0c38d1 SR |
3282 | }; |
3283 | ||
3284 | static int show_traces_open(struct inode *inode, struct file *file) | |
3285 | { | |
607e2ea1 SRRH |
3286 | struct trace_array *tr = inode->i_private; |
3287 | struct seq_file *m; | |
3288 | int ret; | |
3289 | ||
60a11774 SR |
3290 | if (tracing_disabled) |
3291 | return -ENODEV; | |
3292 | ||
607e2ea1 SRRH |
3293 | ret = seq_open(file, &show_traces_seq_ops); |
3294 | if (ret) | |
3295 | return ret; | |
3296 | ||
3297 | m = file->private_data; | |
3298 | m->private = tr; | |
3299 | ||
3300 | return 0; | |
bc0c38d1 SR |
3301 | } |
3302 | ||
4acd4d00 SR |
3303 | static ssize_t |
3304 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
3305 | size_t count, loff_t *ppos) | |
3306 | { | |
3307 | return count; | |
3308 | } | |
3309 | ||
098c879e | 3310 | loff_t tracing_lseek(struct file *file, loff_t offset, int whence) |
364829b1 | 3311 | { |
098c879e SRRH |
3312 | int ret; |
3313 | ||
364829b1 | 3314 | if (file->f_mode & FMODE_READ) |
098c879e | 3315 | ret = seq_lseek(file, offset, whence); |
364829b1 | 3316 | else |
098c879e SRRH |
3317 | file->f_pos = ret = 0; |
3318 | ||
3319 | return ret; | |
364829b1 SP |
3320 | } |
3321 | ||
5e2336a0 | 3322 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
3323 | .open = tracing_open, |
3324 | .read = seq_read, | |
4acd4d00 | 3325 | .write = tracing_write_stub, |
098c879e | 3326 | .llseek = tracing_lseek, |
4bf39a94 | 3327 | .release = tracing_release, |
bc0c38d1 SR |
3328 | }; |
3329 | ||
5e2336a0 | 3330 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
3331 | .open = show_traces_open, |
3332 | .read = seq_read, | |
3333 | .release = seq_release, | |
b444786f | 3334 | .llseek = seq_lseek, |
c7078de1 IM |
3335 | }; |
3336 | ||
36dfe925 IM |
3337 | /* |
3338 | * The tracer itself will not take this lock, but still we want | |
3339 | * to provide a consistent cpumask to user-space: | |
3340 | */ | |
3341 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
3342 | ||
3343 | /* | |
3344 | * Temporary storage for the character representation of the | |
3345 | * CPU bitmask (and one more byte for the newline): | |
3346 | */ | |
3347 | static char mask_str[NR_CPUS + 1]; | |
3348 | ||
c7078de1 IM |
3349 | static ssize_t |
3350 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
3351 | size_t count, loff_t *ppos) | |
3352 | { | |
ccfe9e42 | 3353 | struct trace_array *tr = file_inode(filp)->i_private; |
36dfe925 | 3354 | int len; |
c7078de1 IM |
3355 | |
3356 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 3357 | |
ccfe9e42 | 3358 | len = cpumask_scnprintf(mask_str, count, tr->tracing_cpumask); |
36dfe925 IM |
3359 | if (count - len < 2) { |
3360 | count = -EINVAL; | |
3361 | goto out_err; | |
3362 | } | |
3363 | len += sprintf(mask_str + len, "\n"); | |
3364 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
3365 | ||
3366 | out_err: | |
c7078de1 IM |
3367 | mutex_unlock(&tracing_cpumask_update_lock); |
3368 | ||
3369 | return count; | |
3370 | } | |
3371 | ||
3372 | static ssize_t | |
3373 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
3374 | size_t count, loff_t *ppos) | |
3375 | { | |
ccfe9e42 | 3376 | struct trace_array *tr = file_inode(filp)->i_private; |
9e01c1b7 | 3377 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 3378 | int err, cpu; |
9e01c1b7 RR |
3379 | |
3380 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
3381 | return -ENOMEM; | |
c7078de1 | 3382 | |
9e01c1b7 | 3383 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 3384 | if (err) |
36dfe925 IM |
3385 | goto err_unlock; |
3386 | ||
215368e8 LZ |
3387 | mutex_lock(&tracing_cpumask_update_lock); |
3388 | ||
a5e25883 | 3389 | local_irq_disable(); |
0b9b12c1 | 3390 | arch_spin_lock(&tr->max_lock); |
ab46428c | 3391 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
3392 | /* |
3393 | * Increase/decrease the disabled counter if we are | |
3394 | * about to flip a bit in the cpumask: | |
3395 | */ | |
ccfe9e42 | 3396 | if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3397 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3398 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3399 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 3400 | } |
ccfe9e42 | 3401 | if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3402 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3403 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3404 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
3405 | } |
3406 | } | |
0b9b12c1 | 3407 | arch_spin_unlock(&tr->max_lock); |
a5e25883 | 3408 | local_irq_enable(); |
36dfe925 | 3409 | |
ccfe9e42 | 3410 | cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
3411 | |
3412 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 3413 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
3414 | |
3415 | return count; | |
36dfe925 IM |
3416 | |
3417 | err_unlock: | |
215368e8 | 3418 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
3419 | |
3420 | return err; | |
c7078de1 IM |
3421 | } |
3422 | ||
5e2336a0 | 3423 | static const struct file_operations tracing_cpumask_fops = { |
ccfe9e42 | 3424 | .open = tracing_open_generic_tr, |
c7078de1 IM |
3425 | .read = tracing_cpumask_read, |
3426 | .write = tracing_cpumask_write, | |
ccfe9e42 | 3427 | .release = tracing_release_generic_tr, |
b444786f | 3428 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3429 | }; |
3430 | ||
fdb372ed | 3431 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 3432 | { |
d8e83d26 | 3433 | struct tracer_opt *trace_opts; |
2b6080f2 | 3434 | struct trace_array *tr = m->private; |
d8e83d26 | 3435 | u32 tracer_flags; |
d8e83d26 | 3436 | int i; |
adf9f195 | 3437 | |
d8e83d26 | 3438 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3439 | tracer_flags = tr->current_trace->flags->val; |
3440 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 3441 | |
bc0c38d1 SR |
3442 | for (i = 0; trace_options[i]; i++) { |
3443 | if (trace_flags & (1 << i)) | |
fdb372ed | 3444 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 3445 | else |
fdb372ed | 3446 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
3447 | } |
3448 | ||
adf9f195 FW |
3449 | for (i = 0; trace_opts[i].name; i++) { |
3450 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 3451 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 3452 | else |
fdb372ed | 3453 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 3454 | } |
d8e83d26 | 3455 | mutex_unlock(&trace_types_lock); |
adf9f195 | 3456 | |
fdb372ed | 3457 | return 0; |
bc0c38d1 | 3458 | } |
bc0c38d1 | 3459 | |
8c1a49ae | 3460 | static int __set_tracer_option(struct trace_array *tr, |
8d18eaaf LZ |
3461 | struct tracer_flags *tracer_flags, |
3462 | struct tracer_opt *opts, int neg) | |
3463 | { | |
8c1a49ae | 3464 | struct tracer *trace = tr->current_trace; |
8d18eaaf | 3465 | int ret; |
bc0c38d1 | 3466 | |
8c1a49ae | 3467 | ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); |
8d18eaaf LZ |
3468 | if (ret) |
3469 | return ret; | |
3470 | ||
3471 | if (neg) | |
3472 | tracer_flags->val &= ~opts->bit; | |
3473 | else | |
3474 | tracer_flags->val |= opts->bit; | |
3475 | return 0; | |
bc0c38d1 SR |
3476 | } |
3477 | ||
adf9f195 | 3478 | /* Try to assign a tracer specific option */ |
8c1a49ae | 3479 | static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) |
adf9f195 | 3480 | { |
8c1a49ae | 3481 | struct tracer *trace = tr->current_trace; |
7770841e | 3482 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 3483 | struct tracer_opt *opts = NULL; |
8d18eaaf | 3484 | int i; |
adf9f195 | 3485 | |
7770841e Z |
3486 | for (i = 0; tracer_flags->opts[i].name; i++) { |
3487 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 3488 | |
8d18eaaf | 3489 | if (strcmp(cmp, opts->name) == 0) |
8c1a49ae | 3490 | return __set_tracer_option(tr, trace->flags, opts, neg); |
adf9f195 | 3491 | } |
adf9f195 | 3492 | |
8d18eaaf | 3493 | return -EINVAL; |
adf9f195 FW |
3494 | } |
3495 | ||
613f04a0 SRRH |
3496 | /* Some tracers require overwrite to stay enabled */ |
3497 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
3498 | { | |
3499 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
3500 | return -1; | |
3501 | ||
3502 | return 0; | |
3503 | } | |
3504 | ||
2b6080f2 | 3505 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
3506 | { |
3507 | /* do nothing if flag is already set */ | |
3508 | if (!!(trace_flags & mask) == !!enabled) | |
613f04a0 SRRH |
3509 | return 0; |
3510 | ||
3511 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 | 3512 | if (tr->current_trace->flag_changed) |
bf6065b5 | 3513 | if (tr->current_trace->flag_changed(tr, mask, !!enabled)) |
613f04a0 | 3514 | return -EINVAL; |
af4617bd SR |
3515 | |
3516 | if (enabled) | |
3517 | trace_flags |= mask; | |
3518 | else | |
3519 | trace_flags &= ~mask; | |
e870e9a1 LZ |
3520 | |
3521 | if (mask == TRACE_ITER_RECORD_CMD) | |
3522 | trace_event_enable_cmd_record(enabled); | |
750912fa | 3523 | |
80902822 | 3524 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 3525 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 3526 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 3527 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
3528 | #endif |
3529 | } | |
81698831 SR |
3530 | |
3531 | if (mask == TRACE_ITER_PRINTK) | |
3532 | trace_printk_start_stop_comm(enabled); | |
613f04a0 SRRH |
3533 | |
3534 | return 0; | |
af4617bd SR |
3535 | } |
3536 | ||
2b6080f2 | 3537 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 3538 | { |
8d18eaaf | 3539 | char *cmp; |
bc0c38d1 | 3540 | int neg = 0; |
613f04a0 | 3541 | int ret = -ENODEV; |
bc0c38d1 SR |
3542 | int i; |
3543 | ||
7bcfaf54 | 3544 | cmp = strstrip(option); |
bc0c38d1 | 3545 | |
8d18eaaf | 3546 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3547 | neg = 1; |
3548 | cmp += 2; | |
3549 | } | |
3550 | ||
69d34da2 SRRH |
3551 | mutex_lock(&trace_types_lock); |
3552 | ||
bc0c38d1 | 3553 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3554 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3555 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3556 | break; |
3557 | } | |
3558 | } | |
adf9f195 FW |
3559 | |
3560 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3561 | if (!trace_options[i]) |
8c1a49ae | 3562 | ret = set_tracer_option(tr, cmp, neg); |
69d34da2 SRRH |
3563 | |
3564 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3565 | |
7bcfaf54 SR |
3566 | return ret; |
3567 | } | |
3568 | ||
3569 | static ssize_t | |
3570 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3571 | size_t cnt, loff_t *ppos) | |
3572 | { | |
2b6080f2 SR |
3573 | struct seq_file *m = filp->private_data; |
3574 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3575 | char buf[64]; |
613f04a0 | 3576 | int ret; |
7bcfaf54 SR |
3577 | |
3578 | if (cnt >= sizeof(buf)) | |
3579 | return -EINVAL; | |
3580 | ||
3581 | if (copy_from_user(&buf, ubuf, cnt)) | |
3582 | return -EFAULT; | |
3583 | ||
a8dd2176 SR |
3584 | buf[cnt] = 0; |
3585 | ||
2b6080f2 | 3586 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
3587 | if (ret < 0) |
3588 | return ret; | |
7bcfaf54 | 3589 | |
cf8517cf | 3590 | *ppos += cnt; |
bc0c38d1 SR |
3591 | |
3592 | return cnt; | |
3593 | } | |
3594 | ||
fdb372ed LZ |
3595 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
3596 | { | |
7b85af63 | 3597 | struct trace_array *tr = inode->i_private; |
f77d09a3 | 3598 | int ret; |
7b85af63 | 3599 | |
fdb372ed LZ |
3600 | if (tracing_disabled) |
3601 | return -ENODEV; | |
2b6080f2 | 3602 | |
7b85af63 SRRH |
3603 | if (trace_array_get(tr) < 0) |
3604 | return -ENODEV; | |
3605 | ||
f77d09a3 AL |
3606 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
3607 | if (ret < 0) | |
3608 | trace_array_put(tr); | |
3609 | ||
3610 | return ret; | |
fdb372ed LZ |
3611 | } |
3612 | ||
5e2336a0 | 3613 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
3614 | .open = tracing_trace_options_open, |
3615 | .read = seq_read, | |
3616 | .llseek = seq_lseek, | |
7b85af63 | 3617 | .release = tracing_single_release_tr, |
ee6bce52 | 3618 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
3619 | }; |
3620 | ||
7bd2f24c IM |
3621 | static const char readme_msg[] = |
3622 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
3623 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
3624 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
3625 | " Important files:\n" | |
3626 | " trace\t\t\t- The static contents of the buffer\n" | |
3627 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
3628 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
3629 | " current_tracer\t- function and latency tracers\n" | |
3630 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
3631 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" | |
3632 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
3633 | " trace_clock\t\t-change the clock used to order events\n" | |
3634 | " local: Per cpu clock but may not be synced across CPUs\n" | |
3635 | " global: Synced across CPUs but slows tracing down.\n" | |
3636 | " counter: Not a clock, but just an increment\n" | |
3637 | " uptime: Jiffy counter from time of boot\n" | |
3638 | " perf: Same clock that perf events use\n" | |
3639 | #ifdef CONFIG_X86_64 | |
3640 | " x86-tsc: TSC cycle counter\n" | |
3641 | #endif | |
3642 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" | |
3643 | " tracing_cpumask\t- Limit which CPUs to trace\n" | |
3644 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
3645 | "\t\t\t Remove sub-buffer with rmdir\n" | |
3646 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
71485c45 SRRH |
3647 | "\t\t\t Disable an option by adding a suffix 'no' to the\n" |
3648 | "\t\t\t option name\n" | |
939c7a4f | 3649 | " saved_cmdlines_size\t- echo command number in here to store comm-pid list\n" |
22f45649 SRRH |
3650 | #ifdef CONFIG_DYNAMIC_FTRACE |
3651 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
71485c45 SRRH |
3652 | " set_ftrace_filter\t- echo function name in here to only trace these\n" |
3653 | "\t\t\t functions\n" | |
3654 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3655 | "\t modules: Can select a group via module\n" | |
3656 | "\t Format: :mod:<module-name>\n" | |
3657 | "\t example: echo :mod:ext3 > set_ftrace_filter\n" | |
3658 | "\t triggers: a command to perform when function is hit\n" | |
3659 | "\t Format: <function>:<trigger>[:count]\n" | |
3660 | "\t trigger: traceon, traceoff\n" | |
3661 | "\t\t enable_event:<system>:<event>\n" | |
3662 | "\t\t disable_event:<system>:<event>\n" | |
22f45649 | 3663 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3664 | "\t\t stacktrace\n" |
22f45649 SRRH |
3665 | #endif |
3666 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3667 | "\t\t snapshot\n" |
22f45649 | 3668 | #endif |
17a280ea SRRH |
3669 | "\t\t dump\n" |
3670 | "\t\t cpudump\n" | |
71485c45 SRRH |
3671 | "\t example: echo do_fault:traceoff > set_ftrace_filter\n" |
3672 | "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
3673 | "\t The first one will disable tracing every time do_fault is hit\n" | |
3674 | "\t The second will disable tracing at most 3 times when do_trap is hit\n" | |
3675 | "\t The first time do trap is hit and it disables tracing, the\n" | |
3676 | "\t counter will decrement to 2. If tracing is already disabled,\n" | |
3677 | "\t the counter will not decrement. It only decrements when the\n" | |
3678 | "\t trigger did work\n" | |
3679 | "\t To remove trigger without count:\n" | |
3680 | "\t echo '!<function>:<trigger> > set_ftrace_filter\n" | |
3681 | "\t To remove trigger with a count:\n" | |
3682 | "\t echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
22f45649 | 3683 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" |
71485c45 SRRH |
3684 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" |
3685 | "\t modules: Can select a group via module command :mod:\n" | |
3686 | "\t Does not accept triggers\n" | |
22f45649 SRRH |
3687 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
3688 | #ifdef CONFIG_FUNCTION_TRACER | |
71485c45 SRRH |
3689 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" |
3690 | "\t\t (function)\n" | |
22f45649 SRRH |
3691 | #endif |
3692 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
3693 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
d048a8c7 | 3694 | " set_graph_notrace\t- Do not trace the nested calls of a function (function_graph)\n" |
22f45649 SRRH |
3695 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" |
3696 | #endif | |
3697 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 SRRH |
3698 | "\n snapshot\t\t- Like 'trace' but shows the content of the static\n" |
3699 | "\t\t\t snapshot buffer. Read the contents for more\n" | |
3700 | "\t\t\t information\n" | |
22f45649 | 3701 | #endif |
991821c8 | 3702 | #ifdef CONFIG_STACK_TRACER |
22f45649 SRRH |
3703 | " stack_trace\t\t- Shows the max stack trace when active\n" |
3704 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
71485c45 SRRH |
3705 | "\t\t\t Write into this file to reset the max size (trigger a\n" |
3706 | "\t\t\t new trace)\n" | |
22f45649 | 3707 | #ifdef CONFIG_DYNAMIC_FTRACE |
71485c45 SRRH |
3708 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n" |
3709 | "\t\t\t traces\n" | |
22f45649 | 3710 | #endif |
991821c8 | 3711 | #endif /* CONFIG_STACK_TRACER */ |
26f25564 TZ |
3712 | " events/\t\t- Directory containing all trace event subsystems:\n" |
3713 | " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" | |
3714 | " events/<system>/\t- Directory containing all trace events for <system>:\n" | |
71485c45 SRRH |
3715 | " enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n" |
3716 | "\t\t\t events\n" | |
26f25564 | 3717 | " filter\t\t- If set, only events passing filter are traced\n" |
71485c45 SRRH |
3718 | " events/<system>/<event>/\t- Directory containing control files for\n" |
3719 | "\t\t\t <event>:\n" | |
26f25564 TZ |
3720 | " enable\t\t- Write 0/1 to enable/disable tracing of <event>\n" |
3721 | " filter\t\t- If set, only events passing filter are traced\n" | |
3722 | " trigger\t\t- If set, a command to perform when event is hit\n" | |
71485c45 SRRH |
3723 | "\t Format: <trigger>[:count][if <filter>]\n" |
3724 | "\t trigger: traceon, traceoff\n" | |
3725 | "\t enable_event:<system>:<event>\n" | |
3726 | "\t disable_event:<system>:<event>\n" | |
26f25564 | 3727 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3728 | "\t\t stacktrace\n" |
26f25564 TZ |
3729 | #endif |
3730 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3731 | "\t\t snapshot\n" |
26f25564 | 3732 | #endif |
71485c45 SRRH |
3733 | "\t example: echo traceoff > events/block/block_unplug/trigger\n" |
3734 | "\t echo traceoff:3 > events/block/block_unplug/trigger\n" | |
3735 | "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" | |
3736 | "\t events/block/block_unplug/trigger\n" | |
3737 | "\t The first disables tracing every time block_unplug is hit.\n" | |
3738 | "\t The second disables tracing the first 3 times block_unplug is hit.\n" | |
3739 | "\t The third enables the kmalloc event the first 3 times block_unplug\n" | |
3740 | "\t is hit and has value of greater than 1 for the 'nr_rq' event field.\n" | |
3741 | "\t Like function triggers, the counter is only decremented if it\n" | |
3742 | "\t enabled or disabled tracing.\n" | |
3743 | "\t To remove a trigger without a count:\n" | |
3744 | "\t echo '!<trigger> > <system>/<event>/trigger\n" | |
3745 | "\t To remove a trigger with a count:\n" | |
3746 | "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" | |
3747 | "\t Filters can be ignored when removing a trigger.\n" | |
7bd2f24c IM |
3748 | ; |
3749 | ||
3750 | static ssize_t | |
3751 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
3752 | size_t cnt, loff_t *ppos) | |
3753 | { | |
3754 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
3755 | readme_msg, strlen(readme_msg)); | |
3756 | } | |
3757 | ||
5e2336a0 | 3758 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
3759 | .open = tracing_open_generic, |
3760 | .read = tracing_readme_read, | |
b444786f | 3761 | .llseek = generic_file_llseek, |
7bd2f24c IM |
3762 | }; |
3763 | ||
42584c81 YY |
3764 | static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos) |
3765 | { | |
3766 | unsigned int *ptr = v; | |
69abe6a5 | 3767 | |
42584c81 YY |
3768 | if (*pos || m->count) |
3769 | ptr++; | |
69abe6a5 | 3770 | |
42584c81 | 3771 | (*pos)++; |
69abe6a5 | 3772 | |
939c7a4f YY |
3773 | for (; ptr < &savedcmd->map_cmdline_to_pid[savedcmd->cmdline_num]; |
3774 | ptr++) { | |
42584c81 YY |
3775 | if (*ptr == -1 || *ptr == NO_CMDLINE_MAP) |
3776 | continue; | |
69abe6a5 | 3777 | |
42584c81 YY |
3778 | return ptr; |
3779 | } | |
69abe6a5 | 3780 | |
42584c81 YY |
3781 | return NULL; |
3782 | } | |
3783 | ||
3784 | static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos) | |
3785 | { | |
3786 | void *v; | |
3787 | loff_t l = 0; | |
69abe6a5 | 3788 | |
4c27e756 SRRH |
3789 | preempt_disable(); |
3790 | arch_spin_lock(&trace_cmdline_lock); | |
3791 | ||
939c7a4f | 3792 | v = &savedcmd->map_cmdline_to_pid[0]; |
42584c81 YY |
3793 | while (l <= *pos) { |
3794 | v = saved_cmdlines_next(m, v, &l); | |
3795 | if (!v) | |
3796 | return NULL; | |
69abe6a5 AP |
3797 | } |
3798 | ||
42584c81 YY |
3799 | return v; |
3800 | } | |
3801 | ||
3802 | static void saved_cmdlines_stop(struct seq_file *m, void *v) | |
3803 | { | |
4c27e756 SRRH |
3804 | arch_spin_unlock(&trace_cmdline_lock); |
3805 | preempt_enable(); | |
42584c81 | 3806 | } |
69abe6a5 | 3807 | |
42584c81 YY |
3808 | static int saved_cmdlines_show(struct seq_file *m, void *v) |
3809 | { | |
3810 | char buf[TASK_COMM_LEN]; | |
3811 | unsigned int *pid = v; | |
69abe6a5 | 3812 | |
4c27e756 | 3813 | __trace_find_cmdline(*pid, buf); |
42584c81 YY |
3814 | seq_printf(m, "%d %s\n", *pid, buf); |
3815 | return 0; | |
3816 | } | |
3817 | ||
3818 | static const struct seq_operations tracing_saved_cmdlines_seq_ops = { | |
3819 | .start = saved_cmdlines_start, | |
3820 | .next = saved_cmdlines_next, | |
3821 | .stop = saved_cmdlines_stop, | |
3822 | .show = saved_cmdlines_show, | |
3823 | }; | |
3824 | ||
3825 | static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp) | |
3826 | { | |
3827 | if (tracing_disabled) | |
3828 | return -ENODEV; | |
3829 | ||
3830 | return seq_open(filp, &tracing_saved_cmdlines_seq_ops); | |
69abe6a5 AP |
3831 | } |
3832 | ||
3833 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
42584c81 YY |
3834 | .open = tracing_saved_cmdlines_open, |
3835 | .read = seq_read, | |
3836 | .llseek = seq_lseek, | |
3837 | .release = seq_release, | |
69abe6a5 AP |
3838 | }; |
3839 | ||
939c7a4f YY |
3840 | static ssize_t |
3841 | tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf, | |
3842 | size_t cnt, loff_t *ppos) | |
3843 | { | |
3844 | char buf[64]; | |
3845 | int r; | |
3846 | ||
3847 | arch_spin_lock(&trace_cmdline_lock); | |
a6af8fbf | 3848 | r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num); |
939c7a4f YY |
3849 | arch_spin_unlock(&trace_cmdline_lock); |
3850 | ||
3851 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3852 | } | |
3853 | ||
3854 | static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s) | |
3855 | { | |
3856 | kfree(s->saved_cmdlines); | |
3857 | kfree(s->map_cmdline_to_pid); | |
3858 | kfree(s); | |
3859 | } | |
3860 | ||
3861 | static int tracing_resize_saved_cmdlines(unsigned int val) | |
3862 | { | |
3863 | struct saved_cmdlines_buffer *s, *savedcmd_temp; | |
3864 | ||
a6af8fbf | 3865 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
939c7a4f YY |
3866 | if (!s) |
3867 | return -ENOMEM; | |
3868 | ||
3869 | if (allocate_cmdlines_buffer(val, s) < 0) { | |
3870 | kfree(s); | |
3871 | return -ENOMEM; | |
3872 | } | |
3873 | ||
3874 | arch_spin_lock(&trace_cmdline_lock); | |
3875 | savedcmd_temp = savedcmd; | |
3876 | savedcmd = s; | |
3877 | arch_spin_unlock(&trace_cmdline_lock); | |
3878 | free_saved_cmdlines_buffer(savedcmd_temp); | |
3879 | ||
3880 | return 0; | |
3881 | } | |
3882 | ||
3883 | static ssize_t | |
3884 | tracing_saved_cmdlines_size_write(struct file *filp, const char __user *ubuf, | |
3885 | size_t cnt, loff_t *ppos) | |
3886 | { | |
3887 | unsigned long val; | |
3888 | int ret; | |
3889 | ||
3890 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
3891 | if (ret) | |
3892 | return ret; | |
3893 | ||
3894 | /* must have at least 1 entry or less than PID_MAX_DEFAULT */ | |
3895 | if (!val || val > PID_MAX_DEFAULT) | |
3896 | return -EINVAL; | |
3897 | ||
3898 | ret = tracing_resize_saved_cmdlines((unsigned int)val); | |
3899 | if (ret < 0) | |
3900 | return ret; | |
3901 | ||
3902 | *ppos += cnt; | |
3903 | ||
3904 | return cnt; | |
3905 | } | |
3906 | ||
3907 | static const struct file_operations tracing_saved_cmdlines_size_fops = { | |
3908 | .open = tracing_open_generic, | |
3909 | .read = tracing_saved_cmdlines_size_read, | |
3910 | .write = tracing_saved_cmdlines_size_write, | |
3911 | }; | |
3912 | ||
bc0c38d1 SR |
3913 | static ssize_t |
3914 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
3915 | size_t cnt, loff_t *ppos) | |
3916 | { | |
2b6080f2 | 3917 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 3918 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
3919 | int r; |
3920 | ||
3921 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 3922 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
3923 | mutex_unlock(&trace_types_lock); |
3924 | ||
4bf39a94 | 3925 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3926 | } |
3927 | ||
b6f11df2 ACM |
3928 | int tracer_init(struct tracer *t, struct trace_array *tr) |
3929 | { | |
12883efb | 3930 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
3931 | return t->init(tr); |
3932 | } | |
3933 | ||
12883efb | 3934 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
3935 | { |
3936 | int cpu; | |
737223fb | 3937 | |
438ced17 | 3938 | for_each_tracing_cpu(cpu) |
12883efb | 3939 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
3940 | } |
3941 | ||
12883efb | 3942 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 3943 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
3944 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
3945 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
3946 | { |
3947 | int cpu, ret = 0; | |
3948 | ||
3949 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
3950 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
3951 | ret = ring_buffer_resize(trace_buf->buffer, |
3952 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
3953 | if (ret < 0) |
3954 | break; | |
12883efb SRRH |
3955 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
3956 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
3957 | } |
3958 | } else { | |
12883efb SRRH |
3959 | ret = ring_buffer_resize(trace_buf->buffer, |
3960 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 3961 | if (ret == 0) |
12883efb SRRH |
3962 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
3963 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
3964 | } |
3965 | ||
3966 | return ret; | |
3967 | } | |
12883efb | 3968 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 3969 | |
2b6080f2 SR |
3970 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
3971 | unsigned long size, int cpu) | |
73c5162a SR |
3972 | { |
3973 | int ret; | |
3974 | ||
3975 | /* | |
3976 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3977 | * we use the size that was given, and we can forget about |
3978 | * expanding it later. | |
73c5162a | 3979 | */ |
55034cd6 | 3980 | ring_buffer_expanded = true; |
73c5162a | 3981 | |
b382ede6 | 3982 | /* May be called before buffers are initialized */ |
12883efb | 3983 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
3984 | return 0; |
3985 | ||
12883efb | 3986 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
3987 | if (ret < 0) |
3988 | return ret; | |
3989 | ||
12883efb | 3990 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
3991 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
3992 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
3993 | goto out; |
3994 | ||
12883efb | 3995 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 3996 | if (ret < 0) { |
12883efb SRRH |
3997 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
3998 | &tr->trace_buffer, cpu); | |
73c5162a | 3999 | if (r < 0) { |
a123c52b SR |
4000 | /* |
4001 | * AARGH! We are left with different | |
4002 | * size max buffer!!!! | |
4003 | * The max buffer is our "snapshot" buffer. | |
4004 | * When a tracer needs a snapshot (one of the | |
4005 | * latency tracers), it swaps the max buffer | |
4006 | * with the saved snap shot. We succeeded to | |
4007 | * update the size of the main buffer, but failed to | |
4008 | * update the size of the max buffer. But when we tried | |
4009 | * to reset the main buffer to the original size, we | |
4010 | * failed there too. This is very unlikely to | |
4011 | * happen, but if it does, warn and kill all | |
4012 | * tracing. | |
4013 | */ | |
73c5162a SR |
4014 | WARN_ON(1); |
4015 | tracing_disabled = 1; | |
4016 | } | |
4017 | return ret; | |
4018 | } | |
4019 | ||
438ced17 | 4020 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 4021 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 4022 | else |
12883efb | 4023 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 4024 | |
ef710e10 | 4025 | out: |
12883efb SRRH |
4026 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
4027 | ||
438ced17 | 4028 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 4029 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 4030 | else |
12883efb | 4031 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
4032 | |
4033 | return ret; | |
4034 | } | |
4035 | ||
2b6080f2 SR |
4036 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
4037 | unsigned long size, int cpu_id) | |
4f271a2a | 4038 | { |
83f40318 | 4039 | int ret = size; |
4f271a2a VN |
4040 | |
4041 | mutex_lock(&trace_types_lock); | |
4042 | ||
438ced17 VN |
4043 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
4044 | /* make sure, this cpu is enabled in the mask */ | |
4045 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
4046 | ret = -EINVAL; | |
4047 | goto out; | |
4048 | } | |
4049 | } | |
4f271a2a | 4050 | |
2b6080f2 | 4051 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
4052 | if (ret < 0) |
4053 | ret = -ENOMEM; | |
4054 | ||
438ced17 | 4055 | out: |
4f271a2a VN |
4056 | mutex_unlock(&trace_types_lock); |
4057 | ||
4058 | return ret; | |
4059 | } | |
4060 | ||
ef710e10 | 4061 | |
1852fcce SR |
4062 | /** |
4063 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
4064 | * | |
4065 | * To save on memory when the tracing is never used on a system with it | |
4066 | * configured in. The ring buffers are set to a minimum size. But once | |
4067 | * a user starts to use the tracing facility, then they need to grow | |
4068 | * to their default size. | |
4069 | * | |
4070 | * This function is to be called when a tracer is about to be used. | |
4071 | */ | |
4072 | int tracing_update_buffers(void) | |
4073 | { | |
4074 | int ret = 0; | |
4075 | ||
1027fcb2 | 4076 | mutex_lock(&trace_types_lock); |
1852fcce | 4077 | if (!ring_buffer_expanded) |
2b6080f2 | 4078 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 4079 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 4080 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
4081 | |
4082 | return ret; | |
4083 | } | |
4084 | ||
577b785f SR |
4085 | struct trace_option_dentry; |
4086 | ||
4087 | static struct trace_option_dentry * | |
2b6080f2 | 4088 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f SR |
4089 | |
4090 | static void | |
4091 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
4092 | ||
6b450d25 SRRH |
4093 | /* |
4094 | * Used to clear out the tracer before deletion of an instance. | |
4095 | * Must have trace_types_lock held. | |
4096 | */ | |
4097 | static void tracing_set_nop(struct trace_array *tr) | |
4098 | { | |
4099 | if (tr->current_trace == &nop_trace) | |
4100 | return; | |
4101 | ||
50512ab5 | 4102 | tr->current_trace->enabled--; |
6b450d25 SRRH |
4103 | |
4104 | if (tr->current_trace->reset) | |
4105 | tr->current_trace->reset(tr); | |
4106 | ||
4107 | tr->current_trace = &nop_trace; | |
4108 | } | |
4109 | ||
09d23a1d | 4110 | static void update_tracer_options(struct trace_array *tr, struct tracer *t) |
bc0c38d1 | 4111 | { |
577b785f | 4112 | static struct trace_option_dentry *topts; |
09d23a1d SRRH |
4113 | |
4114 | /* Only enable if the directory has been created already. */ | |
4115 | if (!tr->dir) | |
4116 | return; | |
4117 | ||
4118 | /* Currently, only the top instance has options */ | |
4119 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL)) | |
4120 | return; | |
4121 | ||
4122 | destroy_trace_option_files(topts); | |
4123 | topts = create_trace_option_files(tr, t); | |
4124 | } | |
4125 | ||
4126 | static int tracing_set_tracer(struct trace_array *tr, const char *buf) | |
4127 | { | |
bc0c38d1 | 4128 | struct tracer *t; |
12883efb | 4129 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 4130 | bool had_max_tr; |
12883efb | 4131 | #endif |
d9e54076 | 4132 | int ret = 0; |
bc0c38d1 | 4133 | |
1027fcb2 SR |
4134 | mutex_lock(&trace_types_lock); |
4135 | ||
73c5162a | 4136 | if (!ring_buffer_expanded) { |
2b6080f2 | 4137 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 4138 | RING_BUFFER_ALL_CPUS); |
73c5162a | 4139 | if (ret < 0) |
59f586db | 4140 | goto out; |
73c5162a SR |
4141 | ret = 0; |
4142 | } | |
4143 | ||
bc0c38d1 SR |
4144 | for (t = trace_types; t; t = t->next) { |
4145 | if (strcmp(t->name, buf) == 0) | |
4146 | break; | |
4147 | } | |
c2931e05 FW |
4148 | if (!t) { |
4149 | ret = -EINVAL; | |
4150 | goto out; | |
4151 | } | |
2b6080f2 | 4152 | if (t == tr->current_trace) |
bc0c38d1 SR |
4153 | goto out; |
4154 | ||
607e2ea1 SRRH |
4155 | /* Some tracers are only allowed for the top level buffer */ |
4156 | if (!trace_ok_for_array(t, tr)) { | |
4157 | ret = -EINVAL; | |
4158 | goto out; | |
4159 | } | |
4160 | ||
cf6ab6d9 SRRH |
4161 | /* If trace pipe files are being read, we can't change the tracer */ |
4162 | if (tr->current_trace->ref) { | |
4163 | ret = -EBUSY; | |
4164 | goto out; | |
4165 | } | |
4166 | ||
9f029e83 | 4167 | trace_branch_disable(); |
613f04a0 | 4168 | |
50512ab5 | 4169 | tr->current_trace->enabled--; |
613f04a0 | 4170 | |
2b6080f2 SR |
4171 | if (tr->current_trace->reset) |
4172 | tr->current_trace->reset(tr); | |
34600f0e | 4173 | |
12883efb | 4174 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 4175 | tr->current_trace = &nop_trace; |
34600f0e | 4176 | |
45ad21ca SRRH |
4177 | #ifdef CONFIG_TRACER_MAX_TRACE |
4178 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
4179 | |
4180 | if (had_max_tr && !t->use_max_tr) { | |
4181 | /* | |
4182 | * We need to make sure that the update_max_tr sees that | |
4183 | * current_trace changed to nop_trace to keep it from | |
4184 | * swapping the buffers after we resize it. | |
4185 | * The update_max_tr is called from interrupts disabled | |
4186 | * so a synchronized_sched() is sufficient. | |
4187 | */ | |
4188 | synchronize_sched(); | |
3209cff4 | 4189 | free_snapshot(tr); |
ef710e10 | 4190 | } |
12883efb | 4191 | #endif |
09d23a1d | 4192 | update_tracer_options(tr, t); |
12883efb SRRH |
4193 | |
4194 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 4195 | if (t->use_max_tr && !had_max_tr) { |
3209cff4 | 4196 | ret = alloc_snapshot(tr); |
d60da506 HT |
4197 | if (ret < 0) |
4198 | goto out; | |
ef710e10 | 4199 | } |
12883efb | 4200 | #endif |
577b785f | 4201 | |
1c80025a | 4202 | if (t->init) { |
b6f11df2 | 4203 | ret = tracer_init(t, tr); |
1c80025a FW |
4204 | if (ret) |
4205 | goto out; | |
4206 | } | |
bc0c38d1 | 4207 | |
2b6080f2 | 4208 | tr->current_trace = t; |
50512ab5 | 4209 | tr->current_trace->enabled++; |
9f029e83 | 4210 | trace_branch_enable(tr); |
bc0c38d1 SR |
4211 | out: |
4212 | mutex_unlock(&trace_types_lock); | |
4213 | ||
d9e54076 PZ |
4214 | return ret; |
4215 | } | |
4216 | ||
4217 | static ssize_t | |
4218 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
4219 | size_t cnt, loff_t *ppos) | |
4220 | { | |
607e2ea1 | 4221 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 4222 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
4223 | int i; |
4224 | size_t ret; | |
e6e7a65a FW |
4225 | int err; |
4226 | ||
4227 | ret = cnt; | |
d9e54076 | 4228 | |
ee6c2c1b LZ |
4229 | if (cnt > MAX_TRACER_SIZE) |
4230 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
4231 | |
4232 | if (copy_from_user(&buf, ubuf, cnt)) | |
4233 | return -EFAULT; | |
4234 | ||
4235 | buf[cnt] = 0; | |
4236 | ||
4237 | /* strip ending whitespace. */ | |
4238 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
4239 | buf[i] = 0; | |
4240 | ||
607e2ea1 | 4241 | err = tracing_set_tracer(tr, buf); |
e6e7a65a FW |
4242 | if (err) |
4243 | return err; | |
d9e54076 | 4244 | |
cf8517cf | 4245 | *ppos += ret; |
bc0c38d1 | 4246 | |
c2931e05 | 4247 | return ret; |
bc0c38d1 SR |
4248 | } |
4249 | ||
4250 | static ssize_t | |
6508fa76 SF |
4251 | tracing_nsecs_read(unsigned long *ptr, char __user *ubuf, |
4252 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 4253 | { |
bc0c38d1 SR |
4254 | char buf[64]; |
4255 | int r; | |
4256 | ||
cffae437 | 4257 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 4258 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
4259 | if (r > sizeof(buf)) |
4260 | r = sizeof(buf); | |
4bf39a94 | 4261 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
4262 | } |
4263 | ||
4264 | static ssize_t | |
6508fa76 SF |
4265 | tracing_nsecs_write(unsigned long *ptr, const char __user *ubuf, |
4266 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 4267 | { |
5e39841c | 4268 | unsigned long val; |
c6caeeb1 | 4269 | int ret; |
bc0c38d1 | 4270 | |
22fe9b54 PH |
4271 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4272 | if (ret) | |
c6caeeb1 | 4273 | return ret; |
bc0c38d1 SR |
4274 | |
4275 | *ptr = val * 1000; | |
4276 | ||
4277 | return cnt; | |
4278 | } | |
4279 | ||
6508fa76 SF |
4280 | static ssize_t |
4281 | tracing_thresh_read(struct file *filp, char __user *ubuf, | |
4282 | size_t cnt, loff_t *ppos) | |
4283 | { | |
4284 | return tracing_nsecs_read(&tracing_thresh, ubuf, cnt, ppos); | |
4285 | } | |
4286 | ||
4287 | static ssize_t | |
4288 | tracing_thresh_write(struct file *filp, const char __user *ubuf, | |
4289 | size_t cnt, loff_t *ppos) | |
4290 | { | |
4291 | struct trace_array *tr = filp->private_data; | |
4292 | int ret; | |
4293 | ||
4294 | mutex_lock(&trace_types_lock); | |
4295 | ret = tracing_nsecs_write(&tracing_thresh, ubuf, cnt, ppos); | |
4296 | if (ret < 0) | |
4297 | goto out; | |
4298 | ||
4299 | if (tr->current_trace->update_thresh) { | |
4300 | ret = tr->current_trace->update_thresh(tr); | |
4301 | if (ret < 0) | |
4302 | goto out; | |
4303 | } | |
4304 | ||
4305 | ret = cnt; | |
4306 | out: | |
4307 | mutex_unlock(&trace_types_lock); | |
4308 | ||
4309 | return ret; | |
4310 | } | |
4311 | ||
4312 | static ssize_t | |
4313 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
4314 | size_t cnt, loff_t *ppos) | |
4315 | { | |
4316 | return tracing_nsecs_read(filp->private_data, ubuf, cnt, ppos); | |
4317 | } | |
4318 | ||
4319 | static ssize_t | |
4320 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
4321 | size_t cnt, loff_t *ppos) | |
4322 | { | |
4323 | return tracing_nsecs_write(filp->private_data, ubuf, cnt, ppos); | |
4324 | } | |
4325 | ||
b3806b43 SR |
4326 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
4327 | { | |
15544209 | 4328 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4329 | struct trace_iterator *iter; |
b04cc6b1 | 4330 | int ret = 0; |
b3806b43 SR |
4331 | |
4332 | if (tracing_disabled) | |
4333 | return -ENODEV; | |
4334 | ||
7b85af63 SRRH |
4335 | if (trace_array_get(tr) < 0) |
4336 | return -ENODEV; | |
4337 | ||
b04cc6b1 FW |
4338 | mutex_lock(&trace_types_lock); |
4339 | ||
b3806b43 SR |
4340 | /* create a buffer to store the information to pass to userspace */ |
4341 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
4342 | if (!iter) { |
4343 | ret = -ENOMEM; | |
f77d09a3 | 4344 | __trace_array_put(tr); |
b04cc6b1 FW |
4345 | goto out; |
4346 | } | |
b3806b43 | 4347 | |
3a161d99 | 4348 | trace_seq_init(&iter->seq); |
d716ff71 | 4349 | iter->trace = tr->current_trace; |
d7350c3f | 4350 | |
4462344e | 4351 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 4352 | ret = -ENOMEM; |
d7350c3f | 4353 | goto fail; |
4462344e RR |
4354 | } |
4355 | ||
a309720c | 4356 | /* trace pipe does not show start of buffer */ |
4462344e | 4357 | cpumask_setall(iter->started); |
a309720c | 4358 | |
112f38a7 SR |
4359 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
4360 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
4361 | ||
8be0709f | 4362 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 4363 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
4364 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
4365 | ||
15544209 ON |
4366 | iter->tr = tr; |
4367 | iter->trace_buffer = &tr->trace_buffer; | |
4368 | iter->cpu_file = tracing_get_cpu(inode); | |
d7350c3f | 4369 | mutex_init(&iter->mutex); |
b3806b43 SR |
4370 | filp->private_data = iter; |
4371 | ||
107bad8b SR |
4372 | if (iter->trace->pipe_open) |
4373 | iter->trace->pipe_open(iter); | |
107bad8b | 4374 | |
b444786f | 4375 | nonseekable_open(inode, filp); |
cf6ab6d9 SRRH |
4376 | |
4377 | tr->current_trace->ref++; | |
b04cc6b1 FW |
4378 | out: |
4379 | mutex_unlock(&trace_types_lock); | |
4380 | return ret; | |
d7350c3f FW |
4381 | |
4382 | fail: | |
4383 | kfree(iter->trace); | |
4384 | kfree(iter); | |
7b85af63 | 4385 | __trace_array_put(tr); |
d7350c3f FW |
4386 | mutex_unlock(&trace_types_lock); |
4387 | return ret; | |
b3806b43 SR |
4388 | } |
4389 | ||
4390 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
4391 | { | |
4392 | struct trace_iterator *iter = file->private_data; | |
15544209 | 4393 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4394 | |
b04cc6b1 FW |
4395 | mutex_lock(&trace_types_lock); |
4396 | ||
cf6ab6d9 SRRH |
4397 | tr->current_trace->ref--; |
4398 | ||
29bf4a5e | 4399 | if (iter->trace->pipe_close) |
c521efd1 SR |
4400 | iter->trace->pipe_close(iter); |
4401 | ||
b04cc6b1 FW |
4402 | mutex_unlock(&trace_types_lock); |
4403 | ||
4462344e | 4404 | free_cpumask_var(iter->started); |
d7350c3f | 4405 | mutex_destroy(&iter->mutex); |
b3806b43 | 4406 | kfree(iter); |
b3806b43 | 4407 | |
7b85af63 SRRH |
4408 | trace_array_put(tr); |
4409 | ||
b3806b43 SR |
4410 | return 0; |
4411 | } | |
4412 | ||
2a2cc8f7 | 4413 | static unsigned int |
cc60cdc9 | 4414 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 4415 | { |
15693458 SRRH |
4416 | /* Iterators are static, they should be filled or empty */ |
4417 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
4418 | return POLLIN | POLLRDNORM; | |
2a2cc8f7 | 4419 | |
15693458 | 4420 | if (trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
4421 | /* |
4422 | * Always select as readable when in blocking mode | |
4423 | */ | |
4424 | return POLLIN | POLLRDNORM; | |
15693458 | 4425 | else |
12883efb | 4426 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 4427 | filp, poll_table); |
2a2cc8f7 | 4428 | } |
2a2cc8f7 | 4429 | |
cc60cdc9 SR |
4430 | static unsigned int |
4431 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
4432 | { | |
4433 | struct trace_iterator *iter = filp->private_data; | |
4434 | ||
4435 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
4436 | } |
4437 | ||
d716ff71 | 4438 | /* Must be called with iter->mutex held. */ |
ff98781b | 4439 | static int tracing_wait_pipe(struct file *filp) |
b3806b43 SR |
4440 | { |
4441 | struct trace_iterator *iter = filp->private_data; | |
8b8b3683 | 4442 | int ret; |
b3806b43 | 4443 | |
b3806b43 | 4444 | while (trace_empty(iter)) { |
2dc8f095 | 4445 | |
107bad8b | 4446 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 4447 | return -EAGAIN; |
107bad8b | 4448 | } |
2dc8f095 | 4449 | |
b3806b43 | 4450 | /* |
250bfd3d | 4451 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
4452 | * We still block if tracing is disabled, but we have never |
4453 | * read anything. This allows a user to cat this file, and | |
4454 | * then enable tracing. But after we have read something, | |
4455 | * we give an EOF when tracing is again disabled. | |
4456 | * | |
4457 | * iter->pos will be 0 if we haven't read anything. | |
4458 | */ | |
10246fa3 | 4459 | if (!tracing_is_on() && iter->pos) |
b3806b43 | 4460 | break; |
f4874261 SRRH |
4461 | |
4462 | mutex_unlock(&iter->mutex); | |
4463 | ||
e30f53aa | 4464 | ret = wait_on_pipe(iter, false); |
f4874261 SRRH |
4465 | |
4466 | mutex_lock(&iter->mutex); | |
4467 | ||
8b8b3683 SRRH |
4468 | if (ret) |
4469 | return ret; | |
b3806b43 SR |
4470 | } |
4471 | ||
ff98781b EGM |
4472 | return 1; |
4473 | } | |
4474 | ||
4475 | /* | |
4476 | * Consumer reader. | |
4477 | */ | |
4478 | static ssize_t | |
4479 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
4480 | size_t cnt, loff_t *ppos) | |
4481 | { | |
4482 | struct trace_iterator *iter = filp->private_data; | |
4483 | ssize_t sret; | |
4484 | ||
4485 | /* return any leftover data */ | |
4486 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
4487 | if (sret != -EBUSY) | |
4488 | return sret; | |
4489 | ||
f9520750 | 4490 | trace_seq_init(&iter->seq); |
ff98781b | 4491 | |
d7350c3f FW |
4492 | /* |
4493 | * Avoid more than one consumer on a single file descriptor | |
4494 | * This is just a matter of traces coherency, the ring buffer itself | |
4495 | * is protected. | |
4496 | */ | |
4497 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
4498 | if (iter->trace->read) { |
4499 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
4500 | if (sret) | |
4501 | goto out; | |
4502 | } | |
4503 | ||
4504 | waitagain: | |
4505 | sret = tracing_wait_pipe(filp); | |
4506 | if (sret <= 0) | |
4507 | goto out; | |
4508 | ||
b3806b43 | 4509 | /* stop when tracing is finished */ |
ff98781b EGM |
4510 | if (trace_empty(iter)) { |
4511 | sret = 0; | |
107bad8b | 4512 | goto out; |
ff98781b | 4513 | } |
b3806b43 SR |
4514 | |
4515 | if (cnt >= PAGE_SIZE) | |
4516 | cnt = PAGE_SIZE - 1; | |
4517 | ||
53d0aa77 | 4518 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
4519 | memset(&iter->seq, 0, |
4520 | sizeof(struct trace_iterator) - | |
4521 | offsetof(struct trace_iterator, seq)); | |
ed5467da | 4522 | cpumask_clear(iter->started); |
4823ed7e | 4523 | iter->pos = -1; |
b3806b43 | 4524 | |
4f535968 | 4525 | trace_event_read_lock(); |
7e53bd42 | 4526 | trace_access_lock(iter->cpu_file); |
955b61e5 | 4527 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 4528 | enum print_line_t ret; |
5ac48378 | 4529 | int save_len = iter->seq.seq.len; |
088b1e42 | 4530 | |
f9896bf3 | 4531 | ret = print_trace_line(iter); |
2c4f035f | 4532 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 | 4533 | /* don't print partial lines */ |
5ac48378 | 4534 | iter->seq.seq.len = save_len; |
b3806b43 | 4535 | break; |
088b1e42 | 4536 | } |
b91facc3 FW |
4537 | if (ret != TRACE_TYPE_NO_CONSUME) |
4538 | trace_consume(iter); | |
b3806b43 | 4539 | |
5ac48378 | 4540 | if (trace_seq_used(&iter->seq) >= cnt) |
b3806b43 | 4541 | break; |
ee5e51f5 JO |
4542 | |
4543 | /* | |
4544 | * Setting the full flag means we reached the trace_seq buffer | |
4545 | * size and we should leave by partial output condition above. | |
4546 | * One of the trace_seq_* functions is not used properly. | |
4547 | */ | |
4548 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
4549 | iter->ent->type); | |
b3806b43 | 4550 | } |
7e53bd42 | 4551 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4552 | trace_event_read_unlock(); |
b3806b43 | 4553 | |
b3806b43 | 4554 | /* Now copy what we have to the user */ |
6c6c2796 | 4555 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
5ac48378 | 4556 | if (iter->seq.seq.readpos >= trace_seq_used(&iter->seq)) |
f9520750 | 4557 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
4558 | |
4559 | /* | |
25985edc | 4560 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
4561 | * entries, go back to wait for more entries. |
4562 | */ | |
6c6c2796 | 4563 | if (sret == -EBUSY) |
9ff4b974 | 4564 | goto waitagain; |
b3806b43 | 4565 | |
107bad8b | 4566 | out: |
d7350c3f | 4567 | mutex_unlock(&iter->mutex); |
107bad8b | 4568 | |
6c6c2796 | 4569 | return sret; |
b3806b43 SR |
4570 | } |
4571 | ||
3c56819b EGM |
4572 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, |
4573 | unsigned int idx) | |
4574 | { | |
4575 | __free_page(spd->pages[idx]); | |
4576 | } | |
4577 | ||
28dfef8f | 4578 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 | 4579 | .can_merge = 0, |
34cd4998 | 4580 | .confirm = generic_pipe_buf_confirm, |
92fdd98c | 4581 | .release = generic_pipe_buf_release, |
34cd4998 SR |
4582 | .steal = generic_pipe_buf_steal, |
4583 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
4584 | }; |
4585 | ||
34cd4998 | 4586 | static size_t |
fa7c7f6e | 4587 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
4588 | { |
4589 | size_t count; | |
74f06bb7 | 4590 | int save_len; |
34cd4998 SR |
4591 | int ret; |
4592 | ||
4593 | /* Seq buffer is page-sized, exactly what we need. */ | |
4594 | for (;;) { | |
74f06bb7 | 4595 | save_len = iter->seq.seq.len; |
34cd4998 | 4596 | ret = print_trace_line(iter); |
74f06bb7 SRRH |
4597 | |
4598 | if (trace_seq_has_overflowed(&iter->seq)) { | |
4599 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
4600 | break; |
4601 | } | |
74f06bb7 SRRH |
4602 | |
4603 | /* | |
4604 | * This should not be hit, because it should only | |
4605 | * be set if the iter->seq overflowed. But check it | |
4606 | * anyway to be safe. | |
4607 | */ | |
34cd4998 | 4608 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
74f06bb7 SRRH |
4609 | iter->seq.seq.len = save_len; |
4610 | break; | |
4611 | } | |
4612 | ||
5ac48378 | 4613 | count = trace_seq_used(&iter->seq) - save_len; |
74f06bb7 SRRH |
4614 | if (rem < count) { |
4615 | rem = 0; | |
4616 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
4617 | break; |
4618 | } | |
4619 | ||
74e7ff8c LJ |
4620 | if (ret != TRACE_TYPE_NO_CONSUME) |
4621 | trace_consume(iter); | |
34cd4998 | 4622 | rem -= count; |
955b61e5 | 4623 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
4624 | rem = 0; |
4625 | iter->ent = NULL; | |
4626 | break; | |
4627 | } | |
4628 | } | |
4629 | ||
4630 | return rem; | |
4631 | } | |
4632 | ||
3c56819b EGM |
4633 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
4634 | loff_t *ppos, | |
4635 | struct pipe_inode_info *pipe, | |
4636 | size_t len, | |
4637 | unsigned int flags) | |
4638 | { | |
35f3d14d JA |
4639 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
4640 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
4641 | struct trace_iterator *iter = filp->private_data; |
4642 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
4643 | .pages = pages_def, |
4644 | .partial = partial_def, | |
34cd4998 | 4645 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 4646 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
4647 | .flags = flags, |
4648 | .ops = &tracing_pipe_buf_ops, | |
4649 | .spd_release = tracing_spd_release_pipe, | |
3c56819b EGM |
4650 | }; |
4651 | ssize_t ret; | |
34cd4998 | 4652 | size_t rem; |
3c56819b EGM |
4653 | unsigned int i; |
4654 | ||
35f3d14d JA |
4655 | if (splice_grow_spd(pipe, &spd)) |
4656 | return -ENOMEM; | |
4657 | ||
d7350c3f | 4658 | mutex_lock(&iter->mutex); |
3c56819b EGM |
4659 | |
4660 | if (iter->trace->splice_read) { | |
4661 | ret = iter->trace->splice_read(iter, filp, | |
4662 | ppos, pipe, len, flags); | |
4663 | if (ret) | |
34cd4998 | 4664 | goto out_err; |
3c56819b EGM |
4665 | } |
4666 | ||
4667 | ret = tracing_wait_pipe(filp); | |
4668 | if (ret <= 0) | |
34cd4998 | 4669 | goto out_err; |
3c56819b | 4670 | |
955b61e5 | 4671 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 4672 | ret = -EFAULT; |
34cd4998 | 4673 | goto out_err; |
3c56819b EGM |
4674 | } |
4675 | ||
4f535968 | 4676 | trace_event_read_lock(); |
7e53bd42 | 4677 | trace_access_lock(iter->cpu_file); |
4f535968 | 4678 | |
3c56819b | 4679 | /* Fill as many pages as possible. */ |
a786c06d | 4680 | for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) { |
35f3d14d JA |
4681 | spd.pages[i] = alloc_page(GFP_KERNEL); |
4682 | if (!spd.pages[i]) | |
34cd4998 | 4683 | break; |
3c56819b | 4684 | |
fa7c7f6e | 4685 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
4686 | |
4687 | /* Copy the data into the page, so we can start over. */ | |
4688 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 4689 | page_address(spd.pages[i]), |
5ac48378 | 4690 | trace_seq_used(&iter->seq)); |
3c56819b | 4691 | if (ret < 0) { |
35f3d14d | 4692 | __free_page(spd.pages[i]); |
3c56819b EGM |
4693 | break; |
4694 | } | |
35f3d14d | 4695 | spd.partial[i].offset = 0; |
5ac48378 | 4696 | spd.partial[i].len = trace_seq_used(&iter->seq); |
3c56819b | 4697 | |
f9520750 | 4698 | trace_seq_init(&iter->seq); |
3c56819b EGM |
4699 | } |
4700 | ||
7e53bd42 | 4701 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4702 | trace_event_read_unlock(); |
d7350c3f | 4703 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
4704 | |
4705 | spd.nr_pages = i; | |
4706 | ||
35f3d14d JA |
4707 | ret = splice_to_pipe(pipe, &spd); |
4708 | out: | |
047fe360 | 4709 | splice_shrink_spd(&spd); |
35f3d14d | 4710 | return ret; |
3c56819b | 4711 | |
34cd4998 | 4712 | out_err: |
d7350c3f | 4713 | mutex_unlock(&iter->mutex); |
35f3d14d | 4714 | goto out; |
3c56819b EGM |
4715 | } |
4716 | ||
a98a3c3f SR |
4717 | static ssize_t |
4718 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
4719 | size_t cnt, loff_t *ppos) | |
4720 | { | |
0bc392ee ON |
4721 | struct inode *inode = file_inode(filp); |
4722 | struct trace_array *tr = inode->i_private; | |
4723 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
4724 | char buf[64]; |
4725 | int r = 0; | |
4726 | ssize_t ret; | |
a98a3c3f | 4727 | |
db526ca3 | 4728 | mutex_lock(&trace_types_lock); |
438ced17 | 4729 | |
0bc392ee | 4730 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
4731 | int cpu, buf_size_same; |
4732 | unsigned long size; | |
4733 | ||
4734 | size = 0; | |
4735 | buf_size_same = 1; | |
4736 | /* check if all cpu sizes are same */ | |
4737 | for_each_tracing_cpu(cpu) { | |
4738 | /* fill in the size from first enabled cpu */ | |
4739 | if (size == 0) | |
12883efb SRRH |
4740 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
4741 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
4742 | buf_size_same = 0; |
4743 | break; | |
4744 | } | |
4745 | } | |
4746 | ||
4747 | if (buf_size_same) { | |
4748 | if (!ring_buffer_expanded) | |
4749 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
4750 | size >> 10, | |
4751 | trace_buf_size >> 10); | |
4752 | else | |
4753 | r = sprintf(buf, "%lu\n", size >> 10); | |
4754 | } else | |
4755 | r = sprintf(buf, "X\n"); | |
4756 | } else | |
0bc392ee | 4757 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10); |
438ced17 | 4758 | |
db526ca3 SR |
4759 | mutex_unlock(&trace_types_lock); |
4760 | ||
438ced17 VN |
4761 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
4762 | return ret; | |
a98a3c3f SR |
4763 | } |
4764 | ||
4765 | static ssize_t | |
4766 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
4767 | size_t cnt, loff_t *ppos) | |
4768 | { | |
0bc392ee ON |
4769 | struct inode *inode = file_inode(filp); |
4770 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 4771 | unsigned long val; |
4f271a2a | 4772 | int ret; |
a98a3c3f | 4773 | |
22fe9b54 PH |
4774 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4775 | if (ret) | |
c6caeeb1 | 4776 | return ret; |
a98a3c3f SR |
4777 | |
4778 | /* must have at least 1 entry */ | |
4779 | if (!val) | |
4780 | return -EINVAL; | |
4781 | ||
1696b2b0 SR |
4782 | /* value is in KB */ |
4783 | val <<= 10; | |
0bc392ee | 4784 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
4785 | if (ret < 0) |
4786 | return ret; | |
a98a3c3f | 4787 | |
cf8517cf | 4788 | *ppos += cnt; |
a98a3c3f | 4789 | |
4f271a2a VN |
4790 | return cnt; |
4791 | } | |
bf5e6519 | 4792 | |
f81ab074 VN |
4793 | static ssize_t |
4794 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
4795 | size_t cnt, loff_t *ppos) | |
4796 | { | |
4797 | struct trace_array *tr = filp->private_data; | |
4798 | char buf[64]; | |
4799 | int r, cpu; | |
4800 | unsigned long size = 0, expanded_size = 0; | |
4801 | ||
4802 | mutex_lock(&trace_types_lock); | |
4803 | for_each_tracing_cpu(cpu) { | |
12883efb | 4804 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
4805 | if (!ring_buffer_expanded) |
4806 | expanded_size += trace_buf_size >> 10; | |
4807 | } | |
4808 | if (ring_buffer_expanded) | |
4809 | r = sprintf(buf, "%lu\n", size); | |
4810 | else | |
4811 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
4812 | mutex_unlock(&trace_types_lock); | |
4813 | ||
4814 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4815 | } | |
4816 | ||
4f271a2a VN |
4817 | static ssize_t |
4818 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
4819 | size_t cnt, loff_t *ppos) | |
4820 | { | |
4821 | /* | |
4822 | * There is no need to read what the user has written, this function | |
4823 | * is just to make sure that there is no error when "echo" is used | |
4824 | */ | |
4825 | ||
4826 | *ppos += cnt; | |
a98a3c3f SR |
4827 | |
4828 | return cnt; | |
4829 | } | |
4830 | ||
4f271a2a VN |
4831 | static int |
4832 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
4833 | { | |
2b6080f2 SR |
4834 | struct trace_array *tr = inode->i_private; |
4835 | ||
cf30cf67 SR |
4836 | /* disable tracing ? */ |
4837 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
711e1243 | 4838 | tracer_tracing_off(tr); |
4f271a2a | 4839 | /* resize the ring buffer to 0 */ |
2b6080f2 | 4840 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 4841 | |
7b85af63 SRRH |
4842 | trace_array_put(tr); |
4843 | ||
4f271a2a VN |
4844 | return 0; |
4845 | } | |
4846 | ||
5bf9a1ee PP |
4847 | static ssize_t |
4848 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
4849 | size_t cnt, loff_t *fpos) | |
4850 | { | |
d696b58c | 4851 | unsigned long addr = (unsigned long)ubuf; |
2d71619c | 4852 | struct trace_array *tr = filp->private_data; |
d696b58c SR |
4853 | struct ring_buffer_event *event; |
4854 | struct ring_buffer *buffer; | |
4855 | struct print_entry *entry; | |
4856 | unsigned long irq_flags; | |
4857 | struct page *pages[2]; | |
6edb2a8a | 4858 | void *map_page[2]; |
d696b58c SR |
4859 | int nr_pages = 1; |
4860 | ssize_t written; | |
d696b58c SR |
4861 | int offset; |
4862 | int size; | |
4863 | int len; | |
4864 | int ret; | |
6edb2a8a | 4865 | int i; |
5bf9a1ee | 4866 | |
c76f0694 | 4867 | if (tracing_disabled) |
5bf9a1ee PP |
4868 | return -EINVAL; |
4869 | ||
5224c3a3 MSB |
4870 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
4871 | return -EINVAL; | |
4872 | ||
5bf9a1ee PP |
4873 | if (cnt > TRACE_BUF_SIZE) |
4874 | cnt = TRACE_BUF_SIZE; | |
4875 | ||
d696b58c SR |
4876 | /* |
4877 | * Userspace is injecting traces into the kernel trace buffer. | |
4878 | * We want to be as non intrusive as possible. | |
4879 | * To do so, we do not want to allocate any special buffers | |
4880 | * or take any locks, but instead write the userspace data | |
4881 | * straight into the ring buffer. | |
4882 | * | |
4883 | * First we need to pin the userspace buffer into memory, | |
4884 | * which, most likely it is, because it just referenced it. | |
4885 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
4886 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
4887 | * pages directly. We then write the data directly into the | |
4888 | * ring buffer. | |
4889 | */ | |
4890 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 4891 | |
d696b58c SR |
4892 | /* check if we cross pages */ |
4893 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
4894 | nr_pages = 2; | |
4895 | ||
4896 | offset = addr & (PAGE_SIZE - 1); | |
4897 | addr &= PAGE_MASK; | |
4898 | ||
4899 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
4900 | if (ret < nr_pages) { | |
4901 | while (--ret >= 0) | |
4902 | put_page(pages[ret]); | |
4903 | written = -EFAULT; | |
4904 | goto out; | |
5bf9a1ee | 4905 | } |
d696b58c | 4906 | |
6edb2a8a SR |
4907 | for (i = 0; i < nr_pages; i++) |
4908 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
4909 | |
4910 | local_save_flags(irq_flags); | |
4911 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
2d71619c | 4912 | buffer = tr->trace_buffer.buffer; |
d696b58c SR |
4913 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
4914 | irq_flags, preempt_count()); | |
4915 | if (!event) { | |
4916 | /* Ring buffer disabled, return as if not open for write */ | |
4917 | written = -EBADF; | |
4918 | goto out_unlock; | |
5bf9a1ee | 4919 | } |
d696b58c SR |
4920 | |
4921 | entry = ring_buffer_event_data(event); | |
4922 | entry->ip = _THIS_IP_; | |
4923 | ||
4924 | if (nr_pages == 2) { | |
4925 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
4926 | memcpy(&entry->buf, map_page[0] + offset, len); |
4927 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 4928 | } else |
6edb2a8a | 4929 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 4930 | |
d696b58c SR |
4931 | if (entry->buf[cnt - 1] != '\n') { |
4932 | entry->buf[cnt] = '\n'; | |
4933 | entry->buf[cnt + 1] = '\0'; | |
4934 | } else | |
4935 | entry->buf[cnt] = '\0'; | |
4936 | ||
7ffbd48d | 4937 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 4938 | |
d696b58c | 4939 | written = cnt; |
5bf9a1ee | 4940 | |
d696b58c | 4941 | *fpos += written; |
1aa54bca | 4942 | |
d696b58c | 4943 | out_unlock: |
6edb2a8a SR |
4944 | for (i = 0; i < nr_pages; i++){ |
4945 | kunmap_atomic(map_page[i]); | |
4946 | put_page(pages[i]); | |
4947 | } | |
d696b58c | 4948 | out: |
1aa54bca | 4949 | return written; |
5bf9a1ee PP |
4950 | } |
4951 | ||
13f16d20 | 4952 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 4953 | { |
2b6080f2 | 4954 | struct trace_array *tr = m->private; |
5079f326 Z |
4955 | int i; |
4956 | ||
4957 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 4958 | seq_printf(m, |
5079f326 | 4959 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
4960 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
4961 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 4962 | seq_putc(m, '\n'); |
5079f326 | 4963 | |
13f16d20 | 4964 | return 0; |
5079f326 Z |
4965 | } |
4966 | ||
e1e232ca | 4967 | static int tracing_set_clock(struct trace_array *tr, const char *clockstr) |
5079f326 | 4968 | { |
5079f326 Z |
4969 | int i; |
4970 | ||
5079f326 Z |
4971 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { |
4972 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
4973 | break; | |
4974 | } | |
4975 | if (i == ARRAY_SIZE(trace_clocks)) | |
4976 | return -EINVAL; | |
4977 | ||
5079f326 Z |
4978 | mutex_lock(&trace_types_lock); |
4979 | ||
2b6080f2 SR |
4980 | tr->clock_id = i; |
4981 | ||
12883efb | 4982 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 4983 | |
60303ed3 DS |
4984 | /* |
4985 | * New clock may not be consistent with the previous clock. | |
4986 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
4987 | */ | |
9457158b | 4988 | tracing_reset_online_cpus(&tr->trace_buffer); |
12883efb SRRH |
4989 | |
4990 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4991 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) | |
4992 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); | |
9457158b | 4993 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 4994 | #endif |
60303ed3 | 4995 | |
5079f326 Z |
4996 | mutex_unlock(&trace_types_lock); |
4997 | ||
e1e232ca SR |
4998 | return 0; |
4999 | } | |
5000 | ||
5001 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
5002 | size_t cnt, loff_t *fpos) | |
5003 | { | |
5004 | struct seq_file *m = filp->private_data; | |
5005 | struct trace_array *tr = m->private; | |
5006 | char buf[64]; | |
5007 | const char *clockstr; | |
5008 | int ret; | |
5009 | ||
5010 | if (cnt >= sizeof(buf)) | |
5011 | return -EINVAL; | |
5012 | ||
5013 | if (copy_from_user(&buf, ubuf, cnt)) | |
5014 | return -EFAULT; | |
5015 | ||
5016 | buf[cnt] = 0; | |
5017 | ||
5018 | clockstr = strstrip(buf); | |
5019 | ||
5020 | ret = tracing_set_clock(tr, clockstr); | |
5021 | if (ret) | |
5022 | return ret; | |
5023 | ||
5079f326 Z |
5024 | *fpos += cnt; |
5025 | ||
5026 | return cnt; | |
5027 | } | |
5028 | ||
13f16d20 LZ |
5029 | static int tracing_clock_open(struct inode *inode, struct file *file) |
5030 | { | |
7b85af63 SRRH |
5031 | struct trace_array *tr = inode->i_private; |
5032 | int ret; | |
5033 | ||
13f16d20 LZ |
5034 | if (tracing_disabled) |
5035 | return -ENODEV; | |
2b6080f2 | 5036 | |
7b85af63 SRRH |
5037 | if (trace_array_get(tr)) |
5038 | return -ENODEV; | |
5039 | ||
5040 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
5041 | if (ret < 0) | |
5042 | trace_array_put(tr); | |
5043 | ||
5044 | return ret; | |
13f16d20 LZ |
5045 | } |
5046 | ||
6de58e62 SRRH |
5047 | struct ftrace_buffer_info { |
5048 | struct trace_iterator iter; | |
5049 | void *spare; | |
5050 | unsigned int read; | |
5051 | }; | |
5052 | ||
debdd57f HT |
5053 | #ifdef CONFIG_TRACER_SNAPSHOT |
5054 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
5055 | { | |
6484c71c | 5056 | struct trace_array *tr = inode->i_private; |
debdd57f | 5057 | struct trace_iterator *iter; |
2b6080f2 | 5058 | struct seq_file *m; |
debdd57f HT |
5059 | int ret = 0; |
5060 | ||
ff451961 SRRH |
5061 | if (trace_array_get(tr) < 0) |
5062 | return -ENODEV; | |
5063 | ||
debdd57f | 5064 | if (file->f_mode & FMODE_READ) { |
6484c71c | 5065 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
5066 | if (IS_ERR(iter)) |
5067 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
5068 | } else { |
5069 | /* Writes still need the seq_file to hold the private data */ | |
f77d09a3 | 5070 | ret = -ENOMEM; |
2b6080f2 SR |
5071 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
5072 | if (!m) | |
f77d09a3 | 5073 | goto out; |
2b6080f2 SR |
5074 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
5075 | if (!iter) { | |
5076 | kfree(m); | |
f77d09a3 | 5077 | goto out; |
2b6080f2 | 5078 | } |
f77d09a3 AL |
5079 | ret = 0; |
5080 | ||
ff451961 | 5081 | iter->tr = tr; |
6484c71c ON |
5082 | iter->trace_buffer = &tr->max_buffer; |
5083 | iter->cpu_file = tracing_get_cpu(inode); | |
2b6080f2 SR |
5084 | m->private = iter; |
5085 | file->private_data = m; | |
debdd57f | 5086 | } |
f77d09a3 | 5087 | out: |
ff451961 SRRH |
5088 | if (ret < 0) |
5089 | trace_array_put(tr); | |
5090 | ||
debdd57f HT |
5091 | return ret; |
5092 | } | |
5093 | ||
5094 | static ssize_t | |
5095 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5096 | loff_t *ppos) | |
5097 | { | |
2b6080f2 SR |
5098 | struct seq_file *m = filp->private_data; |
5099 | struct trace_iterator *iter = m->private; | |
5100 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
5101 | unsigned long val; |
5102 | int ret; | |
5103 | ||
5104 | ret = tracing_update_buffers(); | |
5105 | if (ret < 0) | |
5106 | return ret; | |
5107 | ||
5108 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5109 | if (ret) | |
5110 | return ret; | |
5111 | ||
5112 | mutex_lock(&trace_types_lock); | |
5113 | ||
2b6080f2 | 5114 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
5115 | ret = -EBUSY; |
5116 | goto out; | |
5117 | } | |
5118 | ||
5119 | switch (val) { | |
5120 | case 0: | |
f1affcaa SRRH |
5121 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
5122 | ret = -EINVAL; | |
5123 | break; | |
debdd57f | 5124 | } |
3209cff4 SRRH |
5125 | if (tr->allocated_snapshot) |
5126 | free_snapshot(tr); | |
debdd57f HT |
5127 | break; |
5128 | case 1: | |
f1affcaa SRRH |
5129 | /* Only allow per-cpu swap if the ring buffer supports it */ |
5130 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
5131 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
5132 | ret = -EINVAL; | |
5133 | break; | |
5134 | } | |
5135 | #endif | |
45ad21ca | 5136 | if (!tr->allocated_snapshot) { |
3209cff4 | 5137 | ret = alloc_snapshot(tr); |
debdd57f HT |
5138 | if (ret < 0) |
5139 | break; | |
debdd57f | 5140 | } |
debdd57f HT |
5141 | local_irq_disable(); |
5142 | /* Now, we're going to swap */ | |
f1affcaa | 5143 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 5144 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 5145 | else |
ce9bae55 | 5146 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
5147 | local_irq_enable(); |
5148 | break; | |
5149 | default: | |
45ad21ca | 5150 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
5151 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
5152 | tracing_reset_online_cpus(&tr->max_buffer); | |
5153 | else | |
5154 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
5155 | } | |
debdd57f HT |
5156 | break; |
5157 | } | |
5158 | ||
5159 | if (ret >= 0) { | |
5160 | *ppos += cnt; | |
5161 | ret = cnt; | |
5162 | } | |
5163 | out: | |
5164 | mutex_unlock(&trace_types_lock); | |
5165 | return ret; | |
5166 | } | |
2b6080f2 SR |
5167 | |
5168 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
5169 | { | |
5170 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
5171 | int ret; |
5172 | ||
5173 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
5174 | |
5175 | if (file->f_mode & FMODE_READ) | |
ff451961 | 5176 | return ret; |
2b6080f2 SR |
5177 | |
5178 | /* If write only, the seq_file is just a stub */ | |
5179 | if (m) | |
5180 | kfree(m->private); | |
5181 | kfree(m); | |
5182 | ||
5183 | return 0; | |
5184 | } | |
5185 | ||
6de58e62 SRRH |
5186 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
5187 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5188 | size_t count, loff_t *ppos); | |
5189 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
5190 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5191 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
5192 | ||
5193 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
5194 | { | |
5195 | struct ftrace_buffer_info *info; | |
5196 | int ret; | |
5197 | ||
5198 | ret = tracing_buffers_open(inode, filp); | |
5199 | if (ret < 0) | |
5200 | return ret; | |
5201 | ||
5202 | info = filp->private_data; | |
5203 | ||
5204 | if (info->iter.trace->use_max_tr) { | |
5205 | tracing_buffers_release(inode, filp); | |
5206 | return -EBUSY; | |
5207 | } | |
5208 | ||
5209 | info->iter.snapshot = true; | |
5210 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
5211 | ||
5212 | return ret; | |
5213 | } | |
5214 | ||
debdd57f HT |
5215 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5216 | ||
5217 | ||
6508fa76 SF |
5218 | static const struct file_operations tracing_thresh_fops = { |
5219 | .open = tracing_open_generic, | |
5220 | .read = tracing_thresh_read, | |
5221 | .write = tracing_thresh_write, | |
5222 | .llseek = generic_file_llseek, | |
5223 | }; | |
5224 | ||
5e2336a0 | 5225 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
5226 | .open = tracing_open_generic, |
5227 | .read = tracing_max_lat_read, | |
5228 | .write = tracing_max_lat_write, | |
b444786f | 5229 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5230 | }; |
5231 | ||
5e2336a0 | 5232 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
5233 | .open = tracing_open_generic, |
5234 | .read = tracing_set_trace_read, | |
5235 | .write = tracing_set_trace_write, | |
b444786f | 5236 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5237 | }; |
5238 | ||
5e2336a0 | 5239 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 5240 | .open = tracing_open_pipe, |
2a2cc8f7 | 5241 | .poll = tracing_poll_pipe, |
4bf39a94 | 5242 | .read = tracing_read_pipe, |
3c56819b | 5243 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 5244 | .release = tracing_release_pipe, |
b444786f | 5245 | .llseek = no_llseek, |
b3806b43 SR |
5246 | }; |
5247 | ||
5e2336a0 | 5248 | static const struct file_operations tracing_entries_fops = { |
0bc392ee | 5249 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
5250 | .read = tracing_entries_read, |
5251 | .write = tracing_entries_write, | |
b444786f | 5252 | .llseek = generic_file_llseek, |
0bc392ee | 5253 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
5254 | }; |
5255 | ||
f81ab074 | 5256 | static const struct file_operations tracing_total_entries_fops = { |
7b85af63 | 5257 | .open = tracing_open_generic_tr, |
f81ab074 VN |
5258 | .read = tracing_total_entries_read, |
5259 | .llseek = generic_file_llseek, | |
7b85af63 | 5260 | .release = tracing_release_generic_tr, |
f81ab074 VN |
5261 | }; |
5262 | ||
4f271a2a | 5263 | static const struct file_operations tracing_free_buffer_fops = { |
7b85af63 | 5264 | .open = tracing_open_generic_tr, |
4f271a2a VN |
5265 | .write = tracing_free_buffer_write, |
5266 | .release = tracing_free_buffer_release, | |
5267 | }; | |
5268 | ||
5e2336a0 | 5269 | static const struct file_operations tracing_mark_fops = { |
7b85af63 | 5270 | .open = tracing_open_generic_tr, |
5bf9a1ee | 5271 | .write = tracing_mark_write, |
b444786f | 5272 | .llseek = generic_file_llseek, |
7b85af63 | 5273 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
5274 | }; |
5275 | ||
5079f326 | 5276 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
5277 | .open = tracing_clock_open, |
5278 | .read = seq_read, | |
5279 | .llseek = seq_lseek, | |
7b85af63 | 5280 | .release = tracing_single_release_tr, |
5079f326 Z |
5281 | .write = tracing_clock_write, |
5282 | }; | |
5283 | ||
debdd57f HT |
5284 | #ifdef CONFIG_TRACER_SNAPSHOT |
5285 | static const struct file_operations snapshot_fops = { | |
5286 | .open = tracing_snapshot_open, | |
5287 | .read = seq_read, | |
5288 | .write = tracing_snapshot_write, | |
098c879e | 5289 | .llseek = tracing_lseek, |
2b6080f2 | 5290 | .release = tracing_snapshot_release, |
debdd57f | 5291 | }; |
debdd57f | 5292 | |
6de58e62 SRRH |
5293 | static const struct file_operations snapshot_raw_fops = { |
5294 | .open = snapshot_raw_open, | |
5295 | .read = tracing_buffers_read, | |
5296 | .release = tracing_buffers_release, | |
5297 | .splice_read = tracing_buffers_splice_read, | |
5298 | .llseek = no_llseek, | |
2cadf913 SR |
5299 | }; |
5300 | ||
6de58e62 SRRH |
5301 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5302 | ||
2cadf913 SR |
5303 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
5304 | { | |
46ef2be0 | 5305 | struct trace_array *tr = inode->i_private; |
2cadf913 | 5306 | struct ftrace_buffer_info *info; |
7b85af63 | 5307 | int ret; |
2cadf913 SR |
5308 | |
5309 | if (tracing_disabled) | |
5310 | return -ENODEV; | |
5311 | ||
7b85af63 SRRH |
5312 | if (trace_array_get(tr) < 0) |
5313 | return -ENODEV; | |
5314 | ||
2cadf913 | 5315 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
7b85af63 SRRH |
5316 | if (!info) { |
5317 | trace_array_put(tr); | |
2cadf913 | 5318 | return -ENOMEM; |
7b85af63 | 5319 | } |
2cadf913 | 5320 | |
a695cb58 SRRH |
5321 | mutex_lock(&trace_types_lock); |
5322 | ||
cc60cdc9 | 5323 | info->iter.tr = tr; |
46ef2be0 | 5324 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 5325 | info->iter.trace = tr->current_trace; |
12883efb | 5326 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 5327 | info->spare = NULL; |
2cadf913 | 5328 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 5329 | info->read = (unsigned int)-1; |
2cadf913 SR |
5330 | |
5331 | filp->private_data = info; | |
5332 | ||
cf6ab6d9 SRRH |
5333 | tr->current_trace->ref++; |
5334 | ||
a695cb58 SRRH |
5335 | mutex_unlock(&trace_types_lock); |
5336 | ||
7b85af63 SRRH |
5337 | ret = nonseekable_open(inode, filp); |
5338 | if (ret < 0) | |
5339 | trace_array_put(tr); | |
5340 | ||
5341 | return ret; | |
2cadf913 SR |
5342 | } |
5343 | ||
cc60cdc9 SR |
5344 | static unsigned int |
5345 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
5346 | { | |
5347 | struct ftrace_buffer_info *info = filp->private_data; | |
5348 | struct trace_iterator *iter = &info->iter; | |
5349 | ||
5350 | return trace_poll(iter, filp, poll_table); | |
5351 | } | |
5352 | ||
2cadf913 SR |
5353 | static ssize_t |
5354 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5355 | size_t count, loff_t *ppos) | |
5356 | { | |
5357 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 5358 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5359 | ssize_t ret; |
6de58e62 | 5360 | ssize_t size; |
2cadf913 | 5361 | |
2dc5d12b SR |
5362 | if (!count) |
5363 | return 0; | |
5364 | ||
6de58e62 | 5365 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
5366 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
5367 | return -EBUSY; | |
6de58e62 SRRH |
5368 | #endif |
5369 | ||
ddd538f3 | 5370 | if (!info->spare) |
12883efb SRRH |
5371 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
5372 | iter->cpu_file); | |
ddd538f3 | 5373 | if (!info->spare) |
d716ff71 | 5374 | return -ENOMEM; |
ddd538f3 | 5375 | |
2cadf913 SR |
5376 | /* Do we have previous read data to read? */ |
5377 | if (info->read < PAGE_SIZE) | |
5378 | goto read; | |
5379 | ||
b627344f | 5380 | again: |
cc60cdc9 | 5381 | trace_access_lock(iter->cpu_file); |
12883efb | 5382 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
5383 | &info->spare, |
5384 | count, | |
cc60cdc9 SR |
5385 | iter->cpu_file, 0); |
5386 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 5387 | |
b627344f SR |
5388 | if (ret < 0) { |
5389 | if (trace_empty(iter)) { | |
d716ff71 SRRH |
5390 | if ((filp->f_flags & O_NONBLOCK)) |
5391 | return -EAGAIN; | |
5392 | ||
e30f53aa | 5393 | ret = wait_on_pipe(iter, false); |
d716ff71 SRRH |
5394 | if (ret) |
5395 | return ret; | |
5396 | ||
b627344f SR |
5397 | goto again; |
5398 | } | |
d716ff71 | 5399 | return 0; |
b627344f | 5400 | } |
436fc280 | 5401 | |
436fc280 | 5402 | info->read = 0; |
b627344f | 5403 | read: |
2cadf913 SR |
5404 | size = PAGE_SIZE - info->read; |
5405 | if (size > count) | |
5406 | size = count; | |
5407 | ||
5408 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
d716ff71 SRRH |
5409 | if (ret == size) |
5410 | return -EFAULT; | |
5411 | ||
2dc5d12b SR |
5412 | size -= ret; |
5413 | ||
2cadf913 SR |
5414 | *ppos += size; |
5415 | info->read += size; | |
5416 | ||
5417 | return size; | |
5418 | } | |
5419 | ||
5420 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
5421 | { | |
5422 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5423 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5424 | |
a695cb58 SRRH |
5425 | mutex_lock(&trace_types_lock); |
5426 | ||
cf6ab6d9 SRRH |
5427 | iter->tr->current_trace->ref--; |
5428 | ||
ff451961 | 5429 | __trace_array_put(iter->tr); |
2cadf913 | 5430 | |
ddd538f3 | 5431 | if (info->spare) |
12883efb | 5432 | ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); |
2cadf913 SR |
5433 | kfree(info); |
5434 | ||
a695cb58 SRRH |
5435 | mutex_unlock(&trace_types_lock); |
5436 | ||
2cadf913 SR |
5437 | return 0; |
5438 | } | |
5439 | ||
5440 | struct buffer_ref { | |
5441 | struct ring_buffer *buffer; | |
5442 | void *page; | |
5443 | int ref; | |
5444 | }; | |
5445 | ||
5446 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
5447 | struct pipe_buffer *buf) | |
5448 | { | |
5449 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5450 | ||
5451 | if (--ref->ref) | |
5452 | return; | |
5453 | ||
5454 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5455 | kfree(ref); | |
5456 | buf->private = 0; | |
5457 | } | |
5458 | ||
2cadf913 SR |
5459 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
5460 | struct pipe_buffer *buf) | |
5461 | { | |
5462 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5463 | ||
5464 | ref->ref++; | |
5465 | } | |
5466 | ||
5467 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 5468 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 | 5469 | .can_merge = 0, |
2cadf913 SR |
5470 | .confirm = generic_pipe_buf_confirm, |
5471 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 5472 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
5473 | .get = buffer_pipe_buf_get, |
5474 | }; | |
5475 | ||
5476 | /* | |
5477 | * Callback from splice_to_pipe(), if we need to release some pages | |
5478 | * at the end of the spd in case we error'ed out in filling the pipe. | |
5479 | */ | |
5480 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
5481 | { | |
5482 | struct buffer_ref *ref = | |
5483 | (struct buffer_ref *)spd->partial[i].private; | |
5484 | ||
5485 | if (--ref->ref) | |
5486 | return; | |
5487 | ||
5488 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5489 | kfree(ref); | |
5490 | spd->partial[i].private = 0; | |
5491 | } | |
5492 | ||
5493 | static ssize_t | |
5494 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5495 | struct pipe_inode_info *pipe, size_t len, | |
5496 | unsigned int flags) | |
5497 | { | |
5498 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5499 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
5500 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
5501 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 5502 | struct splice_pipe_desc spd = { |
35f3d14d JA |
5503 | .pages = pages_def, |
5504 | .partial = partial_def, | |
047fe360 | 5505 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
5506 | .flags = flags, |
5507 | .ops = &buffer_pipe_buf_ops, | |
5508 | .spd_release = buffer_spd_release, | |
5509 | }; | |
5510 | struct buffer_ref *ref; | |
93459c6c | 5511 | int entries, size, i; |
07906da7 | 5512 | ssize_t ret = 0; |
2cadf913 | 5513 | |
6de58e62 | 5514 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
5515 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
5516 | return -EBUSY; | |
6de58e62 SRRH |
5517 | #endif |
5518 | ||
d716ff71 SRRH |
5519 | if (splice_grow_spd(pipe, &spd)) |
5520 | return -ENOMEM; | |
35f3d14d | 5521 | |
d716ff71 SRRH |
5522 | if (*ppos & (PAGE_SIZE - 1)) |
5523 | return -EINVAL; | |
93cfb3c9 LJ |
5524 | |
5525 | if (len & (PAGE_SIZE - 1)) { | |
d716ff71 SRRH |
5526 | if (len < PAGE_SIZE) |
5527 | return -EINVAL; | |
93cfb3c9 LJ |
5528 | len &= PAGE_MASK; |
5529 | } | |
5530 | ||
cc60cdc9 SR |
5531 | again: |
5532 | trace_access_lock(iter->cpu_file); | |
12883efb | 5533 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 5534 | |
a786c06d | 5535 | for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
5536 | struct page *page; |
5537 | int r; | |
5538 | ||
5539 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
07906da7 RV |
5540 | if (!ref) { |
5541 | ret = -ENOMEM; | |
2cadf913 | 5542 | break; |
07906da7 | 5543 | } |
2cadf913 | 5544 | |
7267fa68 | 5545 | ref->ref = 1; |
12883efb | 5546 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 5547 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
2cadf913 | 5548 | if (!ref->page) { |
07906da7 | 5549 | ret = -ENOMEM; |
2cadf913 SR |
5550 | kfree(ref); |
5551 | break; | |
5552 | } | |
5553 | ||
5554 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 5555 | len, iter->cpu_file, 1); |
2cadf913 | 5556 | if (r < 0) { |
7ea59064 | 5557 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
5558 | kfree(ref); |
5559 | break; | |
5560 | } | |
5561 | ||
5562 | /* | |
5563 | * zero out any left over data, this is going to | |
5564 | * user land. | |
5565 | */ | |
5566 | size = ring_buffer_page_len(ref->page); | |
5567 | if (size < PAGE_SIZE) | |
5568 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
5569 | ||
5570 | page = virt_to_page(ref->page); | |
5571 | ||
5572 | spd.pages[i] = page; | |
5573 | spd.partial[i].len = PAGE_SIZE; | |
5574 | spd.partial[i].offset = 0; | |
5575 | spd.partial[i].private = (unsigned long)ref; | |
5576 | spd.nr_pages++; | |
93cfb3c9 | 5577 | *ppos += PAGE_SIZE; |
93459c6c | 5578 | |
12883efb | 5579 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
5580 | } |
5581 | ||
cc60cdc9 | 5582 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
5583 | spd.nr_pages = i; |
5584 | ||
5585 | /* did we read anything? */ | |
5586 | if (!spd.nr_pages) { | |
07906da7 | 5587 | if (ret) |
d716ff71 SRRH |
5588 | return ret; |
5589 | ||
5590 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) | |
5591 | return -EAGAIN; | |
07906da7 | 5592 | |
e30f53aa | 5593 | ret = wait_on_pipe(iter, true); |
8b8b3683 | 5594 | if (ret) |
d716ff71 | 5595 | return ret; |
e30f53aa | 5596 | |
cc60cdc9 | 5597 | goto again; |
2cadf913 SR |
5598 | } |
5599 | ||
5600 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 5601 | splice_shrink_spd(&spd); |
6de58e62 | 5602 | |
2cadf913 SR |
5603 | return ret; |
5604 | } | |
5605 | ||
5606 | static const struct file_operations tracing_buffers_fops = { | |
5607 | .open = tracing_buffers_open, | |
5608 | .read = tracing_buffers_read, | |
cc60cdc9 | 5609 | .poll = tracing_buffers_poll, |
2cadf913 SR |
5610 | .release = tracing_buffers_release, |
5611 | .splice_read = tracing_buffers_splice_read, | |
5612 | .llseek = no_llseek, | |
5613 | }; | |
5614 | ||
c8d77183 SR |
5615 | static ssize_t |
5616 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
5617 | size_t count, loff_t *ppos) | |
5618 | { | |
4d3435b8 ON |
5619 | struct inode *inode = file_inode(filp); |
5620 | struct trace_array *tr = inode->i_private; | |
12883efb | 5621 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
4d3435b8 | 5622 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
5623 | struct trace_seq *s; |
5624 | unsigned long cnt; | |
c64e148a VN |
5625 | unsigned long long t; |
5626 | unsigned long usec_rem; | |
c8d77183 | 5627 | |
e4f2d10f | 5628 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 5629 | if (!s) |
a646365c | 5630 | return -ENOMEM; |
c8d77183 SR |
5631 | |
5632 | trace_seq_init(s); | |
5633 | ||
12883efb | 5634 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5635 | trace_seq_printf(s, "entries: %ld\n", cnt); |
5636 | ||
12883efb | 5637 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5638 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
5639 | ||
12883efb | 5640 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5641 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
5642 | ||
12883efb | 5643 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
5644 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
5645 | ||
58e8eedf | 5646 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 5647 | /* local or global for trace_clock */ |
12883efb | 5648 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
5649 | usec_rem = do_div(t, USEC_PER_SEC); |
5650 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
5651 | t, usec_rem); | |
5652 | ||
12883efb | 5653 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
5654 | usec_rem = do_div(t, USEC_PER_SEC); |
5655 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
5656 | } else { | |
5657 | /* counter or tsc mode for trace_clock */ | |
5658 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 5659 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 5660 | |
11043d8b | 5661 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 5662 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 5663 | } |
c64e148a | 5664 | |
12883efb | 5665 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
5666 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
5667 | ||
12883efb | 5668 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
5669 | trace_seq_printf(s, "read events: %ld\n", cnt); |
5670 | ||
5ac48378 SRRH |
5671 | count = simple_read_from_buffer(ubuf, count, ppos, |
5672 | s->buffer, trace_seq_used(s)); | |
c8d77183 SR |
5673 | |
5674 | kfree(s); | |
5675 | ||
5676 | return count; | |
5677 | } | |
5678 | ||
5679 | static const struct file_operations tracing_stats_fops = { | |
4d3435b8 | 5680 | .open = tracing_open_generic_tr, |
c8d77183 | 5681 | .read = tracing_stats_read, |
b444786f | 5682 | .llseek = generic_file_llseek, |
4d3435b8 | 5683 | .release = tracing_release_generic_tr, |
c8d77183 SR |
5684 | }; |
5685 | ||
bc0c38d1 SR |
5686 | #ifdef CONFIG_DYNAMIC_FTRACE |
5687 | ||
b807c3d0 SR |
5688 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
5689 | { | |
5690 | return 0; | |
5691 | } | |
5692 | ||
bc0c38d1 | 5693 | static ssize_t |
b807c3d0 | 5694 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
5695 | size_t cnt, loff_t *ppos) |
5696 | { | |
a26a2a27 SR |
5697 | static char ftrace_dyn_info_buffer[1024]; |
5698 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 5699 | unsigned long *p = filp->private_data; |
b807c3d0 | 5700 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 5701 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
5702 | int r; |
5703 | ||
b807c3d0 SR |
5704 | mutex_lock(&dyn_info_mutex); |
5705 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 5706 | |
a26a2a27 | 5707 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
5708 | buf[r++] = '\n'; |
5709 | ||
5710 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5711 | ||
5712 | mutex_unlock(&dyn_info_mutex); | |
5713 | ||
5714 | return r; | |
bc0c38d1 SR |
5715 | } |
5716 | ||
5e2336a0 | 5717 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 5718 | .open = tracing_open_generic, |
b807c3d0 | 5719 | .read = tracing_read_dyn_info, |
b444786f | 5720 | .llseek = generic_file_llseek, |
bc0c38d1 | 5721 | }; |
77fd5c15 | 5722 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 5723 | |
77fd5c15 SRRH |
5724 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
5725 | static void | |
5726 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
5727 | { | |
5728 | tracing_snapshot(); | |
5729 | } | |
bc0c38d1 | 5730 | |
77fd5c15 SRRH |
5731 | static void |
5732 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
bc0c38d1 | 5733 | { |
77fd5c15 SRRH |
5734 | unsigned long *count = (long *)data; |
5735 | ||
5736 | if (!*count) | |
5737 | return; | |
bc0c38d1 | 5738 | |
77fd5c15 SRRH |
5739 | if (*count != -1) |
5740 | (*count)--; | |
5741 | ||
5742 | tracing_snapshot(); | |
5743 | } | |
5744 | ||
5745 | static int | |
5746 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
5747 | struct ftrace_probe_ops *ops, void *data) | |
5748 | { | |
5749 | long count = (long)data; | |
5750 | ||
5751 | seq_printf(m, "%ps:", (void *)ip); | |
5752 | ||
fa6f0cc7 | 5753 | seq_puts(m, "snapshot"); |
77fd5c15 SRRH |
5754 | |
5755 | if (count == -1) | |
fa6f0cc7 | 5756 | seq_puts(m, ":unlimited\n"); |
77fd5c15 SRRH |
5757 | else |
5758 | seq_printf(m, ":count=%ld\n", count); | |
5759 | ||
5760 | return 0; | |
5761 | } | |
5762 | ||
5763 | static struct ftrace_probe_ops snapshot_probe_ops = { | |
5764 | .func = ftrace_snapshot, | |
5765 | .print = ftrace_snapshot_print, | |
5766 | }; | |
5767 | ||
5768 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
5769 | .func = ftrace_count_snapshot, | |
5770 | .print = ftrace_snapshot_print, | |
5771 | }; | |
5772 | ||
5773 | static int | |
5774 | ftrace_trace_snapshot_callback(struct ftrace_hash *hash, | |
5775 | char *glob, char *cmd, char *param, int enable) | |
5776 | { | |
5777 | struct ftrace_probe_ops *ops; | |
5778 | void *count = (void *)-1; | |
5779 | char *number; | |
5780 | int ret; | |
5781 | ||
5782 | /* hash funcs only work with set_ftrace_filter */ | |
5783 | if (!enable) | |
5784 | return -EINVAL; | |
5785 | ||
5786 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
5787 | ||
5788 | if (glob[0] == '!') { | |
5789 | unregister_ftrace_function_probe_func(glob+1, ops); | |
5790 | return 0; | |
5791 | } | |
5792 | ||
5793 | if (!param) | |
5794 | goto out_reg; | |
5795 | ||
5796 | number = strsep(¶m, ":"); | |
5797 | ||
5798 | if (!strlen(number)) | |
5799 | goto out_reg; | |
5800 | ||
5801 | /* | |
5802 | * We use the callback data field (which is a pointer) | |
5803 | * as our counter. | |
5804 | */ | |
5805 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
5806 | if (ret) | |
5807 | return ret; | |
5808 | ||
5809 | out_reg: | |
5810 | ret = register_ftrace_function_probe(glob, ops, count); | |
5811 | ||
5812 | if (ret >= 0) | |
5813 | alloc_snapshot(&global_trace); | |
5814 | ||
5815 | return ret < 0 ? ret : 0; | |
5816 | } | |
5817 | ||
5818 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
5819 | .name = "snapshot", | |
5820 | .func = ftrace_trace_snapshot_callback, | |
5821 | }; | |
5822 | ||
38de93ab | 5823 | static __init int register_snapshot_cmd(void) |
77fd5c15 SRRH |
5824 | { |
5825 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
5826 | } | |
5827 | #else | |
38de93ab | 5828 | static inline __init int register_snapshot_cmd(void) { return 0; } |
77fd5c15 | 5829 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ |
bc0c38d1 | 5830 | |
7eeafbca | 5831 | static struct dentry *tracing_get_dentry(struct trace_array *tr) |
bc0c38d1 | 5832 | { |
8434dc93 SRRH |
5833 | if (WARN_ON(!tr->dir)) |
5834 | return ERR_PTR(-ENODEV); | |
5835 | ||
5836 | /* Top directory uses NULL as the parent */ | |
5837 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
5838 | return NULL; | |
5839 | ||
5840 | /* All sub buffers have a descriptor */ | |
2b6080f2 | 5841 | return tr->dir; |
bc0c38d1 SR |
5842 | } |
5843 | ||
2b6080f2 | 5844 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 5845 | { |
b04cc6b1 FW |
5846 | struct dentry *d_tracer; |
5847 | ||
2b6080f2 SR |
5848 | if (tr->percpu_dir) |
5849 | return tr->percpu_dir; | |
b04cc6b1 | 5850 | |
7eeafbca | 5851 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 5852 | if (IS_ERR(d_tracer)) |
b04cc6b1 FW |
5853 | return NULL; |
5854 | ||
8434dc93 | 5855 | tr->percpu_dir = tracefs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 5856 | |
2b6080f2 | 5857 | WARN_ONCE(!tr->percpu_dir, |
8434dc93 | 5858 | "Could not create tracefs directory 'per_cpu/%d'\n", cpu); |
b04cc6b1 | 5859 | |
2b6080f2 | 5860 | return tr->percpu_dir; |
b04cc6b1 FW |
5861 | } |
5862 | ||
649e9c70 ON |
5863 | static struct dentry * |
5864 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
5865 | void *data, long cpu, const struct file_operations *fops) | |
5866 | { | |
5867 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
5868 | ||
5869 | if (ret) /* See tracing_get_cpu() */ | |
5870 | ret->d_inode->i_cdev = (void *)(cpu + 1); | |
5871 | return ret; | |
5872 | } | |
5873 | ||
2b6080f2 | 5874 | static void |
8434dc93 | 5875 | tracing_init_tracefs_percpu(struct trace_array *tr, long cpu) |
b04cc6b1 | 5876 | { |
2b6080f2 | 5877 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 5878 | struct dentry *d_cpu; |
dd49a38c | 5879 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 5880 | |
0a3d7ce7 NK |
5881 | if (!d_percpu) |
5882 | return; | |
5883 | ||
dd49a38c | 5884 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8434dc93 | 5885 | d_cpu = tracefs_create_dir(cpu_dir, d_percpu); |
8656e7a2 | 5886 | if (!d_cpu) { |
8434dc93 | 5887 | pr_warning("Could not create tracefs '%s' entry\n", cpu_dir); |
8656e7a2 FW |
5888 | return; |
5889 | } | |
b04cc6b1 | 5890 | |
8656e7a2 | 5891 | /* per cpu trace_pipe */ |
649e9c70 | 5892 | trace_create_cpu_file("trace_pipe", 0444, d_cpu, |
15544209 | 5893 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
5894 | |
5895 | /* per cpu trace */ | |
649e9c70 | 5896 | trace_create_cpu_file("trace", 0644, d_cpu, |
6484c71c | 5897 | tr, cpu, &tracing_fops); |
7f96f93f | 5898 | |
649e9c70 | 5899 | trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, |
46ef2be0 | 5900 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 5901 | |
649e9c70 | 5902 | trace_create_cpu_file("stats", 0444, d_cpu, |
4d3435b8 | 5903 | tr, cpu, &tracing_stats_fops); |
438ced17 | 5904 | |
649e9c70 | 5905 | trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, |
0bc392ee | 5906 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
5907 | |
5908 | #ifdef CONFIG_TRACER_SNAPSHOT | |
649e9c70 | 5909 | trace_create_cpu_file("snapshot", 0644, d_cpu, |
6484c71c | 5910 | tr, cpu, &snapshot_fops); |
6de58e62 | 5911 | |
649e9c70 | 5912 | trace_create_cpu_file("snapshot_raw", 0444, d_cpu, |
46ef2be0 | 5913 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 5914 | #endif |
b04cc6b1 FW |
5915 | } |
5916 | ||
60a11774 SR |
5917 | #ifdef CONFIG_FTRACE_SELFTEST |
5918 | /* Let selftest have access to static functions in this file */ | |
5919 | #include "trace_selftest.c" | |
5920 | #endif | |
5921 | ||
577b785f SR |
5922 | struct trace_option_dentry { |
5923 | struct tracer_opt *opt; | |
5924 | struct tracer_flags *flags; | |
2b6080f2 | 5925 | struct trace_array *tr; |
577b785f SR |
5926 | struct dentry *entry; |
5927 | }; | |
5928 | ||
5929 | static ssize_t | |
5930 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5931 | loff_t *ppos) | |
5932 | { | |
5933 | struct trace_option_dentry *topt = filp->private_data; | |
5934 | char *buf; | |
5935 | ||
5936 | if (topt->flags->val & topt->opt->bit) | |
5937 | buf = "1\n"; | |
5938 | else | |
5939 | buf = "0\n"; | |
5940 | ||
5941 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5942 | } | |
5943 | ||
5944 | static ssize_t | |
5945 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5946 | loff_t *ppos) | |
5947 | { | |
5948 | struct trace_option_dentry *topt = filp->private_data; | |
5949 | unsigned long val; | |
577b785f SR |
5950 | int ret; |
5951 | ||
22fe9b54 PH |
5952 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5953 | if (ret) | |
577b785f SR |
5954 | return ret; |
5955 | ||
8d18eaaf LZ |
5956 | if (val != 0 && val != 1) |
5957 | return -EINVAL; | |
577b785f | 5958 | |
8d18eaaf | 5959 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 5960 | mutex_lock(&trace_types_lock); |
8c1a49ae | 5961 | ret = __set_tracer_option(topt->tr, topt->flags, |
c757bea9 | 5962 | topt->opt, !val); |
577b785f SR |
5963 | mutex_unlock(&trace_types_lock); |
5964 | if (ret) | |
5965 | return ret; | |
577b785f SR |
5966 | } |
5967 | ||
5968 | *ppos += cnt; | |
5969 | ||
5970 | return cnt; | |
5971 | } | |
5972 | ||
5973 | ||
5974 | static const struct file_operations trace_options_fops = { | |
5975 | .open = tracing_open_generic, | |
5976 | .read = trace_options_read, | |
5977 | .write = trace_options_write, | |
b444786f | 5978 | .llseek = generic_file_llseek, |
577b785f SR |
5979 | }; |
5980 | ||
a8259075 SR |
5981 | static ssize_t |
5982 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5983 | loff_t *ppos) | |
5984 | { | |
5985 | long index = (long)filp->private_data; | |
5986 | char *buf; | |
5987 | ||
5988 | if (trace_flags & (1 << index)) | |
5989 | buf = "1\n"; | |
5990 | else | |
5991 | buf = "0\n"; | |
5992 | ||
5993 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5994 | } | |
5995 | ||
5996 | static ssize_t | |
5997 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5998 | loff_t *ppos) | |
5999 | { | |
2b6080f2 | 6000 | struct trace_array *tr = &global_trace; |
a8259075 | 6001 | long index = (long)filp->private_data; |
a8259075 SR |
6002 | unsigned long val; |
6003 | int ret; | |
6004 | ||
22fe9b54 PH |
6005 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
6006 | if (ret) | |
a8259075 SR |
6007 | return ret; |
6008 | ||
f2d84b65 | 6009 | if (val != 0 && val != 1) |
a8259075 | 6010 | return -EINVAL; |
69d34da2 SRRH |
6011 | |
6012 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 6013 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 6014 | mutex_unlock(&trace_types_lock); |
a8259075 | 6015 | |
613f04a0 SRRH |
6016 | if (ret < 0) |
6017 | return ret; | |
6018 | ||
a8259075 SR |
6019 | *ppos += cnt; |
6020 | ||
6021 | return cnt; | |
6022 | } | |
6023 | ||
a8259075 SR |
6024 | static const struct file_operations trace_options_core_fops = { |
6025 | .open = tracing_open_generic, | |
6026 | .read = trace_options_core_read, | |
6027 | .write = trace_options_core_write, | |
b444786f | 6028 | .llseek = generic_file_llseek, |
a8259075 SR |
6029 | }; |
6030 | ||
5452af66 | 6031 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 6032 | umode_t mode, |
5452af66 FW |
6033 | struct dentry *parent, |
6034 | void *data, | |
6035 | const struct file_operations *fops) | |
6036 | { | |
6037 | struct dentry *ret; | |
6038 | ||
8434dc93 | 6039 | ret = tracefs_create_file(name, mode, parent, data, fops); |
5452af66 | 6040 | if (!ret) |
8434dc93 | 6041 | pr_warning("Could not create tracefs '%s' entry\n", name); |
5452af66 FW |
6042 | |
6043 | return ret; | |
6044 | } | |
6045 | ||
6046 | ||
2b6080f2 | 6047 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
6048 | { |
6049 | struct dentry *d_tracer; | |
a8259075 | 6050 | |
2b6080f2 SR |
6051 | if (tr->options) |
6052 | return tr->options; | |
a8259075 | 6053 | |
7eeafbca | 6054 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 6055 | if (IS_ERR(d_tracer)) |
a8259075 SR |
6056 | return NULL; |
6057 | ||
8434dc93 | 6058 | tr->options = tracefs_create_dir("options", d_tracer); |
2b6080f2 | 6059 | if (!tr->options) { |
8434dc93 | 6060 | pr_warning("Could not create tracefs directory 'options'\n"); |
a8259075 SR |
6061 | return NULL; |
6062 | } | |
6063 | ||
2b6080f2 | 6064 | return tr->options; |
a8259075 SR |
6065 | } |
6066 | ||
577b785f | 6067 | static void |
2b6080f2 SR |
6068 | create_trace_option_file(struct trace_array *tr, |
6069 | struct trace_option_dentry *topt, | |
577b785f SR |
6070 | struct tracer_flags *flags, |
6071 | struct tracer_opt *opt) | |
6072 | { | |
6073 | struct dentry *t_options; | |
577b785f | 6074 | |
2b6080f2 | 6075 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
6076 | if (!t_options) |
6077 | return; | |
6078 | ||
6079 | topt->flags = flags; | |
6080 | topt->opt = opt; | |
2b6080f2 | 6081 | topt->tr = tr; |
577b785f | 6082 | |
5452af66 | 6083 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
6084 | &trace_options_fops); |
6085 | ||
577b785f SR |
6086 | } |
6087 | ||
6088 | static struct trace_option_dentry * | |
2b6080f2 | 6089 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
6090 | { |
6091 | struct trace_option_dentry *topts; | |
6092 | struct tracer_flags *flags; | |
6093 | struct tracer_opt *opts; | |
6094 | int cnt; | |
6095 | ||
6096 | if (!tracer) | |
6097 | return NULL; | |
6098 | ||
6099 | flags = tracer->flags; | |
6100 | ||
6101 | if (!flags || !flags->opts) | |
6102 | return NULL; | |
6103 | ||
6104 | opts = flags->opts; | |
6105 | ||
6106 | for (cnt = 0; opts[cnt].name; cnt++) | |
6107 | ; | |
6108 | ||
0cfe8245 | 6109 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
6110 | if (!topts) |
6111 | return NULL; | |
6112 | ||
6113 | for (cnt = 0; opts[cnt].name; cnt++) | |
2b6080f2 | 6114 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f SR |
6115 | &opts[cnt]); |
6116 | ||
6117 | return topts; | |
6118 | } | |
6119 | ||
6120 | static void | |
6121 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
6122 | { | |
6123 | int cnt; | |
6124 | ||
6125 | if (!topts) | |
6126 | return; | |
6127 | ||
3f4d8f78 | 6128 | for (cnt = 0; topts[cnt].opt; cnt++) |
8434dc93 | 6129 | tracefs_remove(topts[cnt].entry); |
577b785f SR |
6130 | |
6131 | kfree(topts); | |
6132 | } | |
6133 | ||
a8259075 | 6134 | static struct dentry * |
2b6080f2 SR |
6135 | create_trace_option_core_file(struct trace_array *tr, |
6136 | const char *option, long index) | |
a8259075 SR |
6137 | { |
6138 | struct dentry *t_options; | |
a8259075 | 6139 | |
2b6080f2 | 6140 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
6141 | if (!t_options) |
6142 | return NULL; | |
6143 | ||
5452af66 | 6144 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 6145 | &trace_options_core_fops); |
a8259075 SR |
6146 | } |
6147 | ||
2b6080f2 | 6148 | static __init void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
6149 | { |
6150 | struct dentry *t_options; | |
a8259075 SR |
6151 | int i; |
6152 | ||
2b6080f2 | 6153 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
6154 | if (!t_options) |
6155 | return; | |
6156 | ||
5452af66 | 6157 | for (i = 0; trace_options[i]; i++) |
2b6080f2 | 6158 | create_trace_option_core_file(tr, trace_options[i], i); |
a8259075 SR |
6159 | } |
6160 | ||
499e5470 SR |
6161 | static ssize_t |
6162 | rb_simple_read(struct file *filp, char __user *ubuf, | |
6163 | size_t cnt, loff_t *ppos) | |
6164 | { | |
348f0fc2 | 6165 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
6166 | char buf[64]; |
6167 | int r; | |
6168 | ||
10246fa3 | 6169 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
6170 | r = sprintf(buf, "%d\n", r); |
6171 | ||
6172 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
6173 | } | |
6174 | ||
6175 | static ssize_t | |
6176 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
6177 | size_t cnt, loff_t *ppos) | |
6178 | { | |
348f0fc2 | 6179 | struct trace_array *tr = filp->private_data; |
12883efb | 6180 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
6181 | unsigned long val; |
6182 | int ret; | |
6183 | ||
6184 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
6185 | if (ret) | |
6186 | return ret; | |
6187 | ||
6188 | if (buffer) { | |
2df8f8a6 SR |
6189 | mutex_lock(&trace_types_lock); |
6190 | if (val) { | |
10246fa3 | 6191 | tracer_tracing_on(tr); |
2b6080f2 SR |
6192 | if (tr->current_trace->start) |
6193 | tr->current_trace->start(tr); | |
2df8f8a6 | 6194 | } else { |
10246fa3 | 6195 | tracer_tracing_off(tr); |
2b6080f2 SR |
6196 | if (tr->current_trace->stop) |
6197 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
6198 | } |
6199 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
6200 | } |
6201 | ||
6202 | (*ppos)++; | |
6203 | ||
6204 | return cnt; | |
6205 | } | |
6206 | ||
6207 | static const struct file_operations rb_simple_fops = { | |
7b85af63 | 6208 | .open = tracing_open_generic_tr, |
499e5470 SR |
6209 | .read = rb_simple_read, |
6210 | .write = rb_simple_write, | |
7b85af63 | 6211 | .release = tracing_release_generic_tr, |
499e5470 SR |
6212 | .llseek = default_llseek, |
6213 | }; | |
6214 | ||
277ba044 SR |
6215 | struct dentry *trace_instance_dir; |
6216 | ||
6217 | static void | |
8434dc93 | 6218 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer); |
277ba044 | 6219 | |
55034cd6 SRRH |
6220 | static int |
6221 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
6222 | { |
6223 | enum ring_buffer_flags rb_flags; | |
737223fb SRRH |
6224 | |
6225 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; | |
6226 | ||
dced341b SRRH |
6227 | buf->tr = tr; |
6228 | ||
55034cd6 SRRH |
6229 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
6230 | if (!buf->buffer) | |
6231 | return -ENOMEM; | |
737223fb | 6232 | |
55034cd6 SRRH |
6233 | buf->data = alloc_percpu(struct trace_array_cpu); |
6234 | if (!buf->data) { | |
6235 | ring_buffer_free(buf->buffer); | |
6236 | return -ENOMEM; | |
6237 | } | |
737223fb | 6238 | |
737223fb SRRH |
6239 | /* Allocate the first page for all buffers */ |
6240 | set_buffer_entries(&tr->trace_buffer, | |
6241 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
6242 | ||
55034cd6 SRRH |
6243 | return 0; |
6244 | } | |
737223fb | 6245 | |
55034cd6 SRRH |
6246 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
6247 | { | |
6248 | int ret; | |
737223fb | 6249 | |
55034cd6 SRRH |
6250 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
6251 | if (ret) | |
6252 | return ret; | |
737223fb | 6253 | |
55034cd6 SRRH |
6254 | #ifdef CONFIG_TRACER_MAX_TRACE |
6255 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
6256 | allocate_snapshot ? size : 1); | |
6257 | if (WARN_ON(ret)) { | |
737223fb | 6258 | ring_buffer_free(tr->trace_buffer.buffer); |
55034cd6 SRRH |
6259 | free_percpu(tr->trace_buffer.data); |
6260 | return -ENOMEM; | |
6261 | } | |
6262 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 6263 | |
55034cd6 SRRH |
6264 | /* |
6265 | * Only the top level trace array gets its snapshot allocated | |
6266 | * from the kernel command line. | |
6267 | */ | |
6268 | allocate_snapshot = false; | |
737223fb | 6269 | #endif |
55034cd6 | 6270 | return 0; |
737223fb SRRH |
6271 | } |
6272 | ||
f0b70cc4 SRRH |
6273 | static void free_trace_buffer(struct trace_buffer *buf) |
6274 | { | |
6275 | if (buf->buffer) { | |
6276 | ring_buffer_free(buf->buffer); | |
6277 | buf->buffer = NULL; | |
6278 | free_percpu(buf->data); | |
6279 | buf->data = NULL; | |
6280 | } | |
6281 | } | |
6282 | ||
23aaa3c1 SRRH |
6283 | static void free_trace_buffers(struct trace_array *tr) |
6284 | { | |
6285 | if (!tr) | |
6286 | return; | |
6287 | ||
f0b70cc4 | 6288 | free_trace_buffer(&tr->trace_buffer); |
23aaa3c1 SRRH |
6289 | |
6290 | #ifdef CONFIG_TRACER_MAX_TRACE | |
f0b70cc4 | 6291 | free_trace_buffer(&tr->max_buffer); |
23aaa3c1 SRRH |
6292 | #endif |
6293 | } | |
6294 | ||
eae47358 | 6295 | static int instance_mkdir(const char *name) |
737223fb | 6296 | { |
277ba044 SR |
6297 | struct trace_array *tr; |
6298 | int ret; | |
277ba044 SR |
6299 | |
6300 | mutex_lock(&trace_types_lock); | |
6301 | ||
6302 | ret = -EEXIST; | |
6303 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6304 | if (tr->name && strcmp(tr->name, name) == 0) | |
6305 | goto out_unlock; | |
6306 | } | |
6307 | ||
6308 | ret = -ENOMEM; | |
6309 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
6310 | if (!tr) | |
6311 | goto out_unlock; | |
6312 | ||
6313 | tr->name = kstrdup(name, GFP_KERNEL); | |
6314 | if (!tr->name) | |
6315 | goto out_free_tr; | |
6316 | ||
ccfe9e42 AL |
6317 | if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) |
6318 | goto out_free_tr; | |
6319 | ||
6320 | cpumask_copy(tr->tracing_cpumask, cpu_all_mask); | |
6321 | ||
277ba044 SR |
6322 | raw_spin_lock_init(&tr->start_lock); |
6323 | ||
0b9b12c1 SRRH |
6324 | tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
6325 | ||
277ba044 SR |
6326 | tr->current_trace = &nop_trace; |
6327 | ||
6328 | INIT_LIST_HEAD(&tr->systems); | |
6329 | INIT_LIST_HEAD(&tr->events); | |
6330 | ||
737223fb | 6331 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
6332 | goto out_free_tr; |
6333 | ||
8434dc93 | 6334 | tr->dir = tracefs_create_dir(name, trace_instance_dir); |
277ba044 SR |
6335 | if (!tr->dir) |
6336 | goto out_free_tr; | |
6337 | ||
6338 | ret = event_trace_add_tracer(tr->dir, tr); | |
609e85a7 | 6339 | if (ret) { |
8434dc93 | 6340 | tracefs_remove_recursive(tr->dir); |
277ba044 | 6341 | goto out_free_tr; |
609e85a7 | 6342 | } |
277ba044 | 6343 | |
8434dc93 | 6344 | init_tracer_tracefs(tr, tr->dir); |
277ba044 SR |
6345 | |
6346 | list_add(&tr->list, &ftrace_trace_arrays); | |
6347 | ||
6348 | mutex_unlock(&trace_types_lock); | |
6349 | ||
6350 | return 0; | |
6351 | ||
6352 | out_free_tr: | |
23aaa3c1 | 6353 | free_trace_buffers(tr); |
ccfe9e42 | 6354 | free_cpumask_var(tr->tracing_cpumask); |
277ba044 SR |
6355 | kfree(tr->name); |
6356 | kfree(tr); | |
6357 | ||
6358 | out_unlock: | |
6359 | mutex_unlock(&trace_types_lock); | |
6360 | ||
6361 | return ret; | |
6362 | ||
6363 | } | |
6364 | ||
eae47358 | 6365 | static int instance_rmdir(const char *name) |
0c8916c3 SR |
6366 | { |
6367 | struct trace_array *tr; | |
6368 | int found = 0; | |
6369 | int ret; | |
6370 | ||
6371 | mutex_lock(&trace_types_lock); | |
6372 | ||
6373 | ret = -ENODEV; | |
6374 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6375 | if (tr->name && strcmp(tr->name, name) == 0) { | |
6376 | found = 1; | |
6377 | break; | |
6378 | } | |
6379 | } | |
6380 | if (!found) | |
6381 | goto out_unlock; | |
6382 | ||
a695cb58 | 6383 | ret = -EBUSY; |
cf6ab6d9 | 6384 | if (tr->ref || (tr->current_trace && tr->current_trace->ref)) |
a695cb58 SRRH |
6385 | goto out_unlock; |
6386 | ||
0c8916c3 SR |
6387 | list_del(&tr->list); |
6388 | ||
6b450d25 | 6389 | tracing_set_nop(tr); |
0c8916c3 | 6390 | event_trace_del_tracer(tr); |
591dffda | 6391 | ftrace_destroy_function_files(tr); |
0c8916c3 | 6392 | debugfs_remove_recursive(tr->dir); |
a9fcaaac | 6393 | free_trace_buffers(tr); |
0c8916c3 SR |
6394 | |
6395 | kfree(tr->name); | |
6396 | kfree(tr); | |
6397 | ||
6398 | ret = 0; | |
6399 | ||
6400 | out_unlock: | |
6401 | mutex_unlock(&trace_types_lock); | |
6402 | ||
6403 | return ret; | |
6404 | } | |
6405 | ||
277ba044 SR |
6406 | static __init void create_trace_instances(struct dentry *d_tracer) |
6407 | { | |
eae47358 SRRH |
6408 | trace_instance_dir = tracefs_create_instance_dir("instances", d_tracer, |
6409 | instance_mkdir, | |
6410 | instance_rmdir); | |
277ba044 SR |
6411 | if (WARN_ON(!trace_instance_dir)) |
6412 | return; | |
277ba044 SR |
6413 | } |
6414 | ||
2b6080f2 | 6415 | static void |
8434dc93 | 6416 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
2b6080f2 | 6417 | { |
121aaee7 | 6418 | int cpu; |
2b6080f2 | 6419 | |
607e2ea1 SRRH |
6420 | trace_create_file("available_tracers", 0444, d_tracer, |
6421 | tr, &show_traces_fops); | |
6422 | ||
6423 | trace_create_file("current_tracer", 0644, d_tracer, | |
6424 | tr, &set_tracer_fops); | |
6425 | ||
ccfe9e42 AL |
6426 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
6427 | tr, &tracing_cpumask_fops); | |
6428 | ||
2b6080f2 SR |
6429 | trace_create_file("trace_options", 0644, d_tracer, |
6430 | tr, &tracing_iter_fops); | |
6431 | ||
6432 | trace_create_file("trace", 0644, d_tracer, | |
6484c71c | 6433 | tr, &tracing_fops); |
2b6080f2 SR |
6434 | |
6435 | trace_create_file("trace_pipe", 0444, d_tracer, | |
15544209 | 6436 | tr, &tracing_pipe_fops); |
2b6080f2 SR |
6437 | |
6438 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
0bc392ee | 6439 | tr, &tracing_entries_fops); |
2b6080f2 SR |
6440 | |
6441 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
6442 | tr, &tracing_total_entries_fops); | |
6443 | ||
238ae93d | 6444 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
6445 | tr, &tracing_free_buffer_fops); |
6446 | ||
6447 | trace_create_file("trace_marker", 0220, d_tracer, | |
6448 | tr, &tracing_mark_fops); | |
6449 | ||
6450 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
6451 | &trace_clock_fops); | |
6452 | ||
6453 | trace_create_file("tracing_on", 0644, d_tracer, | |
6484c71c | 6454 | tr, &rb_simple_fops); |
ce9bae55 | 6455 | |
6d9b3fa5 SRRH |
6456 | #ifdef CONFIG_TRACER_MAX_TRACE |
6457 | trace_create_file("tracing_max_latency", 0644, d_tracer, | |
6458 | &tr->max_latency, &tracing_max_lat_fops); | |
6459 | #endif | |
6460 | ||
591dffda SRRH |
6461 | if (ftrace_create_function_files(tr, d_tracer)) |
6462 | WARN(1, "Could not allocate function filter files"); | |
6463 | ||
ce9bae55 SRRH |
6464 | #ifdef CONFIG_TRACER_SNAPSHOT |
6465 | trace_create_file("snapshot", 0644, d_tracer, | |
6484c71c | 6466 | tr, &snapshot_fops); |
ce9bae55 | 6467 | #endif |
121aaee7 SRRH |
6468 | |
6469 | for_each_tracing_cpu(cpu) | |
8434dc93 | 6470 | tracing_init_tracefs_percpu(tr, cpu); |
121aaee7 | 6471 | |
2b6080f2 SR |
6472 | } |
6473 | ||
f76180bc SRRH |
6474 | static struct vfsmount *trace_automount(void *ingore) |
6475 | { | |
6476 | struct vfsmount *mnt; | |
6477 | struct file_system_type *type; | |
6478 | ||
6479 | /* | |
6480 | * To maintain backward compatibility for tools that mount | |
6481 | * debugfs to get to the tracing facility, tracefs is automatically | |
6482 | * mounted to the debugfs/tracing directory. | |
6483 | */ | |
6484 | type = get_fs_type("tracefs"); | |
6485 | if (!type) | |
6486 | return NULL; | |
6487 | mnt = vfs_kern_mount(type, 0, "tracefs", NULL); | |
6488 | put_filesystem(type); | |
6489 | if (IS_ERR(mnt)) | |
6490 | return NULL; | |
6491 | mntget(mnt); | |
6492 | ||
6493 | return mnt; | |
6494 | } | |
6495 | ||
7eeafbca SRRH |
6496 | /** |
6497 | * tracing_init_dentry - initialize top level trace array | |
6498 | * | |
6499 | * This is called when creating files or directories in the tracing | |
6500 | * directory. It is called via fs_initcall() by any of the boot up code | |
6501 | * and expects to return the dentry of the top level tracing directory. | |
6502 | */ | |
6503 | struct dentry *tracing_init_dentry(void) | |
6504 | { | |
6505 | struct trace_array *tr = &global_trace; | |
6506 | ||
f76180bc | 6507 | /* The top level trace array uses NULL as parent */ |
7eeafbca | 6508 | if (tr->dir) |
f76180bc | 6509 | return NULL; |
7eeafbca SRRH |
6510 | |
6511 | if (WARN_ON(!debugfs_initialized())) | |
6512 | return ERR_PTR(-ENODEV); | |
6513 | ||
f76180bc SRRH |
6514 | /* |
6515 | * As there may still be users that expect the tracing | |
6516 | * files to exist in debugfs/tracing, we must automount | |
6517 | * the tracefs file system there, so older tools still | |
6518 | * work with the newer kerenl. | |
6519 | */ | |
6520 | tr->dir = debugfs_create_automount("tracing", NULL, | |
6521 | trace_automount, NULL); | |
7eeafbca SRRH |
6522 | if (!tr->dir) { |
6523 | pr_warn_once("Could not create debugfs directory 'tracing'\n"); | |
6524 | return ERR_PTR(-ENOMEM); | |
6525 | } | |
6526 | ||
8434dc93 | 6527 | return NULL; |
7eeafbca SRRH |
6528 | } |
6529 | ||
8434dc93 | 6530 | static __init int tracer_init_tracefs(void) |
bc0c38d1 SR |
6531 | { |
6532 | struct dentry *d_tracer; | |
bc0c38d1 | 6533 | |
7e53bd42 LJ |
6534 | trace_access_lock_init(); |
6535 | ||
bc0c38d1 | 6536 | d_tracer = tracing_init_dentry(); |
14a5ae40 | 6537 | if (IS_ERR(d_tracer)) |
ed6f1c99 | 6538 | return 0; |
bc0c38d1 | 6539 | |
8434dc93 | 6540 | init_tracer_tracefs(&global_trace, d_tracer); |
bc0c38d1 | 6541 | |
5452af66 | 6542 | trace_create_file("tracing_thresh", 0644, d_tracer, |
6508fa76 | 6543 | &global_trace, &tracing_thresh_fops); |
a8259075 | 6544 | |
339ae5d3 | 6545 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
6546 | NULL, &tracing_readme_fops); |
6547 | ||
69abe6a5 AP |
6548 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
6549 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 6550 | |
939c7a4f YY |
6551 | trace_create_file("saved_cmdlines_size", 0644, d_tracer, |
6552 | NULL, &tracing_saved_cmdlines_size_fops); | |
6553 | ||
bc0c38d1 | 6554 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
6555 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
6556 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 6557 | #endif |
b04cc6b1 | 6558 | |
277ba044 | 6559 | create_trace_instances(d_tracer); |
5452af66 | 6560 | |
2b6080f2 | 6561 | create_trace_options_dir(&global_trace); |
b04cc6b1 | 6562 | |
09d23a1d SRRH |
6563 | /* If the tracer was started via cmdline, create options for it here */ |
6564 | if (global_trace.current_trace != &nop_trace) | |
6565 | update_tracer_options(&global_trace, global_trace.current_trace); | |
6566 | ||
b5ad384e | 6567 | return 0; |
bc0c38d1 SR |
6568 | } |
6569 | ||
3f5a54e3 SR |
6570 | static int trace_panic_handler(struct notifier_block *this, |
6571 | unsigned long event, void *unused) | |
6572 | { | |
944ac425 | 6573 | if (ftrace_dump_on_oops) |
cecbca96 | 6574 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6575 | return NOTIFY_OK; |
6576 | } | |
6577 | ||
6578 | static struct notifier_block trace_panic_notifier = { | |
6579 | .notifier_call = trace_panic_handler, | |
6580 | .next = NULL, | |
6581 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
6582 | }; | |
6583 | ||
6584 | static int trace_die_handler(struct notifier_block *self, | |
6585 | unsigned long val, | |
6586 | void *data) | |
6587 | { | |
6588 | switch (val) { | |
6589 | case DIE_OOPS: | |
944ac425 | 6590 | if (ftrace_dump_on_oops) |
cecbca96 | 6591 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6592 | break; |
6593 | default: | |
6594 | break; | |
6595 | } | |
6596 | return NOTIFY_OK; | |
6597 | } | |
6598 | ||
6599 | static struct notifier_block trace_die_notifier = { | |
6600 | .notifier_call = trace_die_handler, | |
6601 | .priority = 200 | |
6602 | }; | |
6603 | ||
6604 | /* | |
6605 | * printk is set to max of 1024, we really don't need it that big. | |
6606 | * Nothing should be printing 1000 characters anyway. | |
6607 | */ | |
6608 | #define TRACE_MAX_PRINT 1000 | |
6609 | ||
6610 | /* | |
6611 | * Define here KERN_TRACE so that we have one place to modify | |
6612 | * it if we decide to change what log level the ftrace dump | |
6613 | * should be at. | |
6614 | */ | |
428aee14 | 6615 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 6616 | |
955b61e5 | 6617 | void |
3f5a54e3 SR |
6618 | trace_printk_seq(struct trace_seq *s) |
6619 | { | |
6620 | /* Probably should print a warning here. */ | |
3a161d99 SRRH |
6621 | if (s->seq.len >= TRACE_MAX_PRINT) |
6622 | s->seq.len = TRACE_MAX_PRINT; | |
3f5a54e3 | 6623 | |
820b75f6 SRRH |
6624 | /* |
6625 | * More paranoid code. Although the buffer size is set to | |
6626 | * PAGE_SIZE, and TRACE_MAX_PRINT is 1000, this is just | |
6627 | * an extra layer of protection. | |
6628 | */ | |
6629 | if (WARN_ON_ONCE(s->seq.len >= s->seq.size)) | |
6630 | s->seq.len = s->seq.size - 1; | |
3f5a54e3 SR |
6631 | |
6632 | /* should be zero ended, but we are paranoid. */ | |
3a161d99 | 6633 | s->buffer[s->seq.len] = 0; |
3f5a54e3 SR |
6634 | |
6635 | printk(KERN_TRACE "%s", s->buffer); | |
6636 | ||
f9520750 | 6637 | trace_seq_init(s); |
3f5a54e3 SR |
6638 | } |
6639 | ||
955b61e5 JW |
6640 | void trace_init_global_iter(struct trace_iterator *iter) |
6641 | { | |
6642 | iter->tr = &global_trace; | |
2b6080f2 | 6643 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 6644 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 6645 | iter->trace_buffer = &global_trace.trace_buffer; |
b2f974d6 CS |
6646 | |
6647 | if (iter->trace && iter->trace->open) | |
6648 | iter->trace->open(iter); | |
6649 | ||
6650 | /* Annotate start of buffers if we had overruns */ | |
6651 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) | |
6652 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
6653 | ||
6654 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ | |
6655 | if (trace_clocks[iter->tr->clock_id].in_ns) | |
6656 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
955b61e5 JW |
6657 | } |
6658 | ||
7fe70b57 | 6659 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 6660 | { |
3f5a54e3 SR |
6661 | /* use static because iter can be a bit big for the stack */ |
6662 | static struct trace_iterator iter; | |
7fe70b57 | 6663 | static atomic_t dump_running; |
cf586b61 | 6664 | unsigned int old_userobj; |
d769041f SR |
6665 | unsigned long flags; |
6666 | int cnt = 0, cpu; | |
3f5a54e3 | 6667 | |
7fe70b57 SRRH |
6668 | /* Only allow one dump user at a time. */ |
6669 | if (atomic_inc_return(&dump_running) != 1) { | |
6670 | atomic_dec(&dump_running); | |
6671 | return; | |
6672 | } | |
3f5a54e3 | 6673 | |
7fe70b57 SRRH |
6674 | /* |
6675 | * Always turn off tracing when we dump. | |
6676 | * We don't need to show trace output of what happens | |
6677 | * between multiple crashes. | |
6678 | * | |
6679 | * If the user does a sysrq-z, then they can re-enable | |
6680 | * tracing with echo 1 > tracing_on. | |
6681 | */ | |
0ee6b6cf | 6682 | tracing_off(); |
cf586b61 | 6683 | |
7fe70b57 | 6684 | local_irq_save(flags); |
3f5a54e3 | 6685 | |
38dbe0b1 | 6686 | /* Simulate the iterator */ |
955b61e5 JW |
6687 | trace_init_global_iter(&iter); |
6688 | ||
d769041f | 6689 | for_each_tracing_cpu(cpu) { |
12883efb | 6690 | atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled); |
d769041f SR |
6691 | } |
6692 | ||
cf586b61 FW |
6693 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
6694 | ||
b54d3de9 TE |
6695 | /* don't look at user memory in panic mode */ |
6696 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
6697 | ||
cecbca96 FW |
6698 | switch (oops_dump_mode) { |
6699 | case DUMP_ALL: | |
ae3b5093 | 6700 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6701 | break; |
6702 | case DUMP_ORIG: | |
6703 | iter.cpu_file = raw_smp_processor_id(); | |
6704 | break; | |
6705 | case DUMP_NONE: | |
6706 | goto out_enable; | |
6707 | default: | |
6708 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 6709 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6710 | } |
6711 | ||
6712 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 6713 | |
7fe70b57 SRRH |
6714 | /* Did function tracer already get disabled? */ |
6715 | if (ftrace_is_dead()) { | |
6716 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
6717 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
6718 | } | |
6719 | ||
3f5a54e3 SR |
6720 | /* |
6721 | * We need to stop all tracing on all CPUS to read the | |
6722 | * the next buffer. This is a bit expensive, but is | |
6723 | * not done often. We fill all what we can read, | |
6724 | * and then release the locks again. | |
6725 | */ | |
6726 | ||
3f5a54e3 SR |
6727 | while (!trace_empty(&iter)) { |
6728 | ||
6729 | if (!cnt) | |
6730 | printk(KERN_TRACE "---------------------------------\n"); | |
6731 | ||
6732 | cnt++; | |
6733 | ||
6734 | /* reset all but tr, trace, and overruns */ | |
6735 | memset(&iter.seq, 0, | |
6736 | sizeof(struct trace_iterator) - | |
6737 | offsetof(struct trace_iterator, seq)); | |
6738 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
6739 | iter.pos = -1; | |
6740 | ||
955b61e5 | 6741 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
6742 | int ret; |
6743 | ||
6744 | ret = print_trace_line(&iter); | |
6745 | if (ret != TRACE_TYPE_NO_CONSUME) | |
6746 | trace_consume(&iter); | |
3f5a54e3 | 6747 | } |
b892e5c8 | 6748 | touch_nmi_watchdog(); |
3f5a54e3 SR |
6749 | |
6750 | trace_printk_seq(&iter.seq); | |
6751 | } | |
6752 | ||
6753 | if (!cnt) | |
6754 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
6755 | else | |
6756 | printk(KERN_TRACE "---------------------------------\n"); | |
6757 | ||
cecbca96 | 6758 | out_enable: |
7fe70b57 | 6759 | trace_flags |= old_userobj; |
cf586b61 | 6760 | |
7fe70b57 SRRH |
6761 | for_each_tracing_cpu(cpu) { |
6762 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); | |
cf586b61 | 6763 | } |
7fe70b57 | 6764 | atomic_dec(&dump_running); |
cd891ae0 | 6765 | local_irq_restore(flags); |
3f5a54e3 | 6766 | } |
a8eecf22 | 6767 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 6768 | |
3928a8a2 | 6769 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 6770 | { |
73c5162a | 6771 | int ring_buf_size; |
9e01c1b7 | 6772 | int ret = -ENOMEM; |
4c11d7ae | 6773 | |
9e01c1b7 RR |
6774 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
6775 | goto out; | |
6776 | ||
ccfe9e42 | 6777 | if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) |
9e01c1b7 | 6778 | goto out_free_buffer_mask; |
4c11d7ae | 6779 | |
07d777fe SR |
6780 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
6781 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 6782 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
6783 | trace_printk_init_buffers(); |
6784 | ||
73c5162a SR |
6785 | /* To save memory, keep the ring buffer size to its minimum */ |
6786 | if (ring_buffer_expanded) | |
6787 | ring_buf_size = trace_buf_size; | |
6788 | else | |
6789 | ring_buf_size = 1; | |
6790 | ||
9e01c1b7 | 6791 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
ccfe9e42 | 6792 | cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); |
9e01c1b7 | 6793 | |
2b6080f2 SR |
6794 | raw_spin_lock_init(&global_trace.start_lock); |
6795 | ||
2c4a33ab SRRH |
6796 | /* Used for event triggers */ |
6797 | temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); | |
6798 | if (!temp_buffer) | |
6799 | goto out_free_cpumask; | |
6800 | ||
939c7a4f YY |
6801 | if (trace_create_savedcmd() < 0) |
6802 | goto out_free_temp_buffer; | |
6803 | ||
9e01c1b7 | 6804 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 6805 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
6806 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
6807 | WARN_ON(1); | |
939c7a4f | 6808 | goto out_free_savedcmd; |
4c11d7ae | 6809 | } |
a7603ff4 | 6810 | |
499e5470 SR |
6811 | if (global_trace.buffer_disabled) |
6812 | tracing_off(); | |
4c11d7ae | 6813 | |
e1e232ca SR |
6814 | if (trace_boot_clock) { |
6815 | ret = tracing_set_clock(&global_trace, trace_boot_clock); | |
6816 | if (ret < 0) | |
6817 | pr_warning("Trace clock %s not defined, going back to default\n", | |
6818 | trace_boot_clock); | |
6819 | } | |
6820 | ||
ca164318 SRRH |
6821 | /* |
6822 | * register_tracer() might reference current_trace, so it | |
6823 | * needs to be set before we register anything. This is | |
6824 | * just a bootstrap of current_trace anyway. | |
6825 | */ | |
2b6080f2 SR |
6826 | global_trace.current_trace = &nop_trace; |
6827 | ||
0b9b12c1 SRRH |
6828 | global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
6829 | ||
4104d326 SRRH |
6830 | ftrace_init_global_array_ops(&global_trace); |
6831 | ||
ca164318 SRRH |
6832 | register_tracer(&nop_trace); |
6833 | ||
60a11774 SR |
6834 | /* All seems OK, enable tracing */ |
6835 | tracing_disabled = 0; | |
3928a8a2 | 6836 | |
3f5a54e3 SR |
6837 | atomic_notifier_chain_register(&panic_notifier_list, |
6838 | &trace_panic_notifier); | |
6839 | ||
6840 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 6841 | |
ae63b31e SR |
6842 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
6843 | ||
6844 | INIT_LIST_HEAD(&global_trace.systems); | |
6845 | INIT_LIST_HEAD(&global_trace.events); | |
6846 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
6847 | ||
7bcfaf54 SR |
6848 | while (trace_boot_options) { |
6849 | char *option; | |
6850 | ||
6851 | option = strsep(&trace_boot_options, ","); | |
2b6080f2 | 6852 | trace_set_options(&global_trace, option); |
7bcfaf54 SR |
6853 | } |
6854 | ||
77fd5c15 SRRH |
6855 | register_snapshot_cmd(); |
6856 | ||
2fc1dfbe | 6857 | return 0; |
3f5a54e3 | 6858 | |
939c7a4f YY |
6859 | out_free_savedcmd: |
6860 | free_saved_cmdlines_buffer(savedcmd); | |
2c4a33ab SRRH |
6861 | out_free_temp_buffer: |
6862 | ring_buffer_free(temp_buffer); | |
9e01c1b7 | 6863 | out_free_cpumask: |
ccfe9e42 | 6864 | free_cpumask_var(global_trace.tracing_cpumask); |
9e01c1b7 RR |
6865 | out_free_buffer_mask: |
6866 | free_cpumask_var(tracing_buffer_mask); | |
6867 | out: | |
6868 | return ret; | |
bc0c38d1 | 6869 | } |
b2821ae6 | 6870 | |
5f893b26 SRRH |
6871 | void __init trace_init(void) |
6872 | { | |
0daa2302 SRRH |
6873 | if (tracepoint_printk) { |
6874 | tracepoint_print_iter = | |
6875 | kmalloc(sizeof(*tracepoint_print_iter), GFP_KERNEL); | |
6876 | if (WARN_ON(!tracepoint_print_iter)) | |
6877 | tracepoint_printk = 0; | |
6878 | } | |
5f893b26 | 6879 | tracer_alloc_buffers(); |
5f893b26 SRRH |
6880 | trace_event_init(); |
6881 | } | |
6882 | ||
b2821ae6 SR |
6883 | __init static int clear_boot_tracer(void) |
6884 | { | |
6885 | /* | |
6886 | * The default tracer at boot buffer is an init section. | |
6887 | * This function is called in lateinit. If we did not | |
6888 | * find the boot tracer, then clear it out, to prevent | |
6889 | * later registration from accessing the buffer that is | |
6890 | * about to be freed. | |
6891 | */ | |
6892 | if (!default_bootup_tracer) | |
6893 | return 0; | |
6894 | ||
6895 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
6896 | default_bootup_tracer); | |
6897 | default_bootup_tracer = NULL; | |
6898 | ||
6899 | return 0; | |
6900 | } | |
6901 | ||
8434dc93 | 6902 | fs_initcall(tracer_init_tracefs); |
b2821ae6 | 6903 | late_initcall(clear_boot_tracer); |