Commit | Line | Data |
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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> |
4c11d7ae | 23 | #include <linux/pagemap.h> |
bc0c38d1 SR |
24 | #include <linux/hardirq.h> |
25 | #include <linux/linkage.h> | |
26 | #include <linux/uaccess.h> | |
2cadf913 | 27 | #include <linux/kprobes.h> |
bc0c38d1 SR |
28 | #include <linux/ftrace.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/percpu.h> | |
2cadf913 | 31 | #include <linux/splice.h> |
3f5a54e3 | 32 | #include <linux/kdebug.h> |
5f0c6c03 | 33 | #include <linux/string.h> |
7e53bd42 | 34 | #include <linux/rwsem.h> |
5a0e3ad6 | 35 | #include <linux/slab.h> |
bc0c38d1 SR |
36 | #include <linux/ctype.h> |
37 | #include <linux/init.h> | |
2a2cc8f7 | 38 | #include <linux/poll.h> |
b892e5c8 | 39 | #include <linux/nmi.h> |
bc0c38d1 | 40 | #include <linux/fs.h> |
8bd75c77 | 41 | #include <linux/sched/rt.h> |
86387f7e | 42 | |
bc0c38d1 | 43 | #include "trace.h" |
f0868d1e | 44 | #include "trace_output.h" |
bc0c38d1 | 45 | |
73c5162a SR |
46 | /* |
47 | * On boot up, the ring buffer is set to the minimum size, so that | |
48 | * we do not waste memory on systems that are not using tracing. | |
49 | */ | |
55034cd6 | 50 | bool ring_buffer_expanded; |
73c5162a | 51 | |
8e1b82e0 FW |
52 | /* |
53 | * We need to change this state when a selftest is running. | |
ff32504f FW |
54 | * A selftest will lurk into the ring-buffer to count the |
55 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 56 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
57 | * at the same time, giving false positive or negative results. |
58 | */ | |
8e1b82e0 | 59 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 60 | |
b2821ae6 SR |
61 | /* |
62 | * If a tracer is running, we do not want to run SELFTEST. | |
63 | */ | |
020e5f85 | 64 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 65 | |
adf9f195 FW |
66 | /* For tracers that don't implement custom flags */ |
67 | static struct tracer_opt dummy_tracer_opt[] = { | |
68 | { } | |
69 | }; | |
70 | ||
71 | static struct tracer_flags dummy_tracer_flags = { | |
72 | .val = 0, | |
73 | .opts = dummy_tracer_opt | |
74 | }; | |
75 | ||
76 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
77 | { | |
78 | return 0; | |
79 | } | |
0f048701 | 80 | |
7ffbd48d SR |
81 | /* |
82 | * To prevent the comm cache from being overwritten when no | |
83 | * tracing is active, only save the comm when a trace event | |
84 | * occurred. | |
85 | */ | |
86 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
87 | ||
0f048701 SR |
88 | /* |
89 | * Kill all tracing for good (never come back). | |
90 | * It is initialized to 1 but will turn to zero if the initialization | |
91 | * of the tracer is successful. But that is the only place that sets | |
92 | * this back to zero. | |
93 | */ | |
4fd27358 | 94 | static int tracing_disabled = 1; |
0f048701 | 95 | |
9288f99a | 96 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 97 | |
955b61e5 | 98 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 99 | |
944ac425 SR |
100 | /* |
101 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
102 | * | |
103 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
104 | * is set, then ftrace_dump is called. This will output the contents | |
105 | * of the ftrace buffers to the console. This is very useful for | |
106 | * capturing traces that lead to crashes and outputing it to a | |
107 | * serial console. | |
108 | * | |
109 | * It is default off, but you can enable it with either specifying | |
110 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
111 | * /proc/sys/kernel/ftrace_dump_on_oops |
112 | * Set 1 if you want to dump buffers of all CPUs | |
113 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 114 | */ |
cecbca96 FW |
115 | |
116 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 117 | |
b2821ae6 SR |
118 | static int tracing_set_tracer(const char *buf); |
119 | ||
ee6c2c1b LZ |
120 | #define MAX_TRACER_SIZE 100 |
121 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 122 | static char *default_bootup_tracer; |
d9e54076 | 123 | |
55034cd6 SRRH |
124 | static bool allocate_snapshot; |
125 | ||
1beee96b | 126 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 127 | { |
ee6c2c1b | 128 | strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 129 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 130 | /* We are using ftrace early, expand it */ |
55034cd6 | 131 | ring_buffer_expanded = true; |
d9e54076 PZ |
132 | return 1; |
133 | } | |
1beee96b | 134 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 135 | |
944ac425 SR |
136 | static int __init set_ftrace_dump_on_oops(char *str) |
137 | { | |
cecbca96 FW |
138 | if (*str++ != '=' || !*str) { |
139 | ftrace_dump_on_oops = DUMP_ALL; | |
140 | return 1; | |
141 | } | |
142 | ||
143 | if (!strcmp("orig_cpu", str)) { | |
144 | ftrace_dump_on_oops = DUMP_ORIG; | |
145 | return 1; | |
146 | } | |
147 | ||
148 | return 0; | |
944ac425 SR |
149 | } |
150 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 151 | |
55034cd6 SRRH |
152 | static int __init alloc_snapshot(char *str) |
153 | { | |
154 | allocate_snapshot = true; | |
155 | /* We also need the main ring buffer expanded */ | |
156 | ring_buffer_expanded = true; | |
157 | return 1; | |
158 | } | |
159 | __setup("alloc_snapshot", alloc_snapshot); | |
160 | ||
7bcfaf54 SR |
161 | |
162 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
163 | static char *trace_boot_options __initdata; | |
164 | ||
165 | static int __init set_trace_boot_options(char *str) | |
166 | { | |
167 | strncpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); | |
168 | trace_boot_options = trace_boot_options_buf; | |
169 | return 0; | |
170 | } | |
171 | __setup("trace_options=", set_trace_boot_options); | |
172 | ||
cf8e3474 | 173 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
174 | { |
175 | nsec += 500; | |
176 | do_div(nsec, 1000); | |
177 | return nsec; | |
178 | } | |
179 | ||
4fcdae83 SR |
180 | /* |
181 | * The global_trace is the descriptor that holds the tracing | |
182 | * buffers for the live tracing. For each CPU, it contains | |
183 | * a link list of pages that will store trace entries. The | |
184 | * page descriptor of the pages in the memory is used to hold | |
185 | * the link list by linking the lru item in the page descriptor | |
186 | * to each of the pages in the buffer per CPU. | |
187 | * | |
188 | * For each active CPU there is a data field that holds the | |
189 | * pages for the buffer for that CPU. Each CPU has the same number | |
190 | * of pages allocated for its buffer. | |
191 | */ | |
bc0c38d1 SR |
192 | static struct trace_array global_trace; |
193 | ||
ae63b31e SR |
194 | LIST_HEAD(ftrace_trace_arrays); |
195 | ||
e77405ad SR |
196 | int filter_current_check_discard(struct ring_buffer *buffer, |
197 | struct ftrace_event_call *call, void *rec, | |
eb02ce01 TZ |
198 | struct ring_buffer_event *event) |
199 | { | |
e77405ad | 200 | return filter_check_discard(call, rec, buffer, event); |
eb02ce01 | 201 | } |
17c873ec | 202 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 203 | |
37886f6a SR |
204 | cycle_t ftrace_now(int cpu) |
205 | { | |
206 | u64 ts; | |
207 | ||
208 | /* Early boot up does not have a buffer yet */ | |
12883efb | 209 | if (!global_trace.trace_buffer.buffer) |
37886f6a SR |
210 | return trace_clock_local(); |
211 | ||
12883efb SRRH |
212 | ts = ring_buffer_time_stamp(global_trace.trace_buffer.buffer, cpu); |
213 | ring_buffer_normalize_time_stamp(global_trace.trace_buffer.buffer, cpu, &ts); | |
37886f6a SR |
214 | |
215 | return ts; | |
216 | } | |
bc0c38d1 | 217 | |
9036990d SR |
218 | int tracing_is_enabled(void) |
219 | { | |
0fb9656d | 220 | return tracing_is_on(); |
9036990d SR |
221 | } |
222 | ||
4fcdae83 | 223 | /* |
3928a8a2 SR |
224 | * trace_buf_size is the size in bytes that is allocated |
225 | * for a buffer. Note, the number of bytes is always rounded | |
226 | * to page size. | |
3f5a54e3 SR |
227 | * |
228 | * This number is purposely set to a low number of 16384. | |
229 | * If the dump on oops happens, it will be much appreciated | |
230 | * to not have to wait for all that output. Anyway this can be | |
231 | * boot time and run time configurable. | |
4fcdae83 | 232 | */ |
3928a8a2 | 233 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 234 | |
3928a8a2 | 235 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 236 | |
4fcdae83 | 237 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 238 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 239 | |
4fcdae83 SR |
240 | /* |
241 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 242 | */ |
bc0c38d1 | 243 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 244 | |
7e53bd42 LJ |
245 | /* |
246 | * serialize the access of the ring buffer | |
247 | * | |
248 | * ring buffer serializes readers, but it is low level protection. | |
249 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
250 | * are not protected by ring buffer. | |
251 | * | |
252 | * The content of events may become garbage if we allow other process consumes | |
253 | * these events concurrently: | |
254 | * A) the page of the consumed events may become a normal page | |
255 | * (not reader page) in ring buffer, and this page will be rewrited | |
256 | * by events producer. | |
257 | * B) The page of the consumed events may become a page for splice_read, | |
258 | * and this page will be returned to system. | |
259 | * | |
260 | * These primitives allow multi process access to different cpu ring buffer | |
261 | * concurrently. | |
262 | * | |
263 | * These primitives don't distinguish read-only and read-consume access. | |
264 | * Multi read-only access are also serialized. | |
265 | */ | |
266 | ||
267 | #ifdef CONFIG_SMP | |
268 | static DECLARE_RWSEM(all_cpu_access_lock); | |
269 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
270 | ||
271 | static inline void trace_access_lock(int cpu) | |
272 | { | |
ae3b5093 | 273 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
274 | /* gain it for accessing the whole ring buffer. */ |
275 | down_write(&all_cpu_access_lock); | |
276 | } else { | |
277 | /* gain it for accessing a cpu ring buffer. */ | |
278 | ||
ae3b5093 | 279 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
280 | down_read(&all_cpu_access_lock); |
281 | ||
282 | /* Secondly block other access to this @cpu ring buffer. */ | |
283 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
284 | } | |
285 | } | |
286 | ||
287 | static inline void trace_access_unlock(int cpu) | |
288 | { | |
ae3b5093 | 289 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
290 | up_write(&all_cpu_access_lock); |
291 | } else { | |
292 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
293 | up_read(&all_cpu_access_lock); | |
294 | } | |
295 | } | |
296 | ||
297 | static inline void trace_access_lock_init(void) | |
298 | { | |
299 | int cpu; | |
300 | ||
301 | for_each_possible_cpu(cpu) | |
302 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
303 | } | |
304 | ||
305 | #else | |
306 | ||
307 | static DEFINE_MUTEX(access_lock); | |
308 | ||
309 | static inline void trace_access_lock(int cpu) | |
310 | { | |
311 | (void)cpu; | |
312 | mutex_lock(&access_lock); | |
313 | } | |
314 | ||
315 | static inline void trace_access_unlock(int cpu) | |
316 | { | |
317 | (void)cpu; | |
318 | mutex_unlock(&access_lock); | |
319 | } | |
320 | ||
321 | static inline void trace_access_lock_init(void) | |
322 | { | |
323 | } | |
324 | ||
325 | #endif | |
326 | ||
ee6bce52 | 327 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 328 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 329 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 | 330 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
5224c3a3 | 331 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS; |
4e655519 | 332 | |
499e5470 SR |
333 | /** |
334 | * tracing_on - enable tracing buffers | |
335 | * | |
336 | * This function enables tracing buffers that may have been | |
337 | * disabled with tracing_off. | |
338 | */ | |
339 | void tracing_on(void) | |
340 | { | |
12883efb SRRH |
341 | if (global_trace.trace_buffer.buffer) |
342 | ring_buffer_record_on(global_trace.trace_buffer.buffer); | |
499e5470 SR |
343 | /* |
344 | * This flag is only looked at when buffers haven't been | |
345 | * allocated yet. We don't really care about the race | |
346 | * between setting this flag and actually turning | |
347 | * on the buffer. | |
348 | */ | |
349 | global_trace.buffer_disabled = 0; | |
350 | } | |
351 | EXPORT_SYMBOL_GPL(tracing_on); | |
352 | ||
09ae7234 SRRH |
353 | /** |
354 | * __trace_puts - write a constant string into the trace buffer. | |
355 | * @ip: The address of the caller | |
356 | * @str: The constant string to write | |
357 | * @size: The size of the string. | |
358 | */ | |
359 | int __trace_puts(unsigned long ip, const char *str, int size) | |
360 | { | |
361 | struct ring_buffer_event *event; | |
362 | struct ring_buffer *buffer; | |
363 | struct print_entry *entry; | |
364 | unsigned long irq_flags; | |
365 | int alloc; | |
366 | ||
367 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ | |
368 | ||
369 | local_save_flags(irq_flags); | |
370 | buffer = global_trace.trace_buffer.buffer; | |
371 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, | |
372 | irq_flags, preempt_count()); | |
373 | if (!event) | |
374 | return 0; | |
375 | ||
376 | entry = ring_buffer_event_data(event); | |
377 | entry->ip = ip; | |
378 | ||
379 | memcpy(&entry->buf, str, size); | |
380 | ||
381 | /* Add a newline if necessary */ | |
382 | if (entry->buf[size - 1] != '\n') { | |
383 | entry->buf[size] = '\n'; | |
384 | entry->buf[size + 1] = '\0'; | |
385 | } else | |
386 | entry->buf[size] = '\0'; | |
387 | ||
388 | __buffer_unlock_commit(buffer, event); | |
389 | ||
390 | return size; | |
391 | } | |
392 | EXPORT_SYMBOL_GPL(__trace_puts); | |
393 | ||
394 | /** | |
395 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
396 | * @ip: The address of the caller | |
397 | * @str: The constant string to write to the buffer to | |
398 | */ | |
399 | int __trace_bputs(unsigned long ip, const char *str) | |
400 | { | |
401 | struct ring_buffer_event *event; | |
402 | struct ring_buffer *buffer; | |
403 | struct bputs_entry *entry; | |
404 | unsigned long irq_flags; | |
405 | int size = sizeof(struct bputs_entry); | |
406 | ||
407 | local_save_flags(irq_flags); | |
408 | buffer = global_trace.trace_buffer.buffer; | |
409 | event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, | |
410 | irq_flags, preempt_count()); | |
411 | if (!event) | |
412 | return 0; | |
413 | ||
414 | entry = ring_buffer_event_data(event); | |
415 | entry->ip = ip; | |
416 | entry->str = str; | |
417 | ||
418 | __buffer_unlock_commit(buffer, event); | |
419 | ||
420 | return 1; | |
421 | } | |
422 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
423 | ||
ad909e21 SRRH |
424 | #ifdef CONFIG_TRACER_SNAPSHOT |
425 | /** | |
426 | * trace_snapshot - take a snapshot of the current buffer. | |
427 | * | |
428 | * This causes a swap between the snapshot buffer and the current live | |
429 | * tracing buffer. You can use this to take snapshots of the live | |
430 | * trace when some condition is triggered, but continue to trace. | |
431 | * | |
432 | * Note, make sure to allocate the snapshot with either | |
433 | * a tracing_snapshot_alloc(), or by doing it manually | |
434 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
435 | * | |
436 | * If the snapshot buffer is not allocated, it will stop tracing. | |
437 | * Basically making a permanent snapshot. | |
438 | */ | |
439 | void tracing_snapshot(void) | |
440 | { | |
441 | struct trace_array *tr = &global_trace; | |
442 | struct tracer *tracer = tr->current_trace; | |
443 | unsigned long flags; | |
444 | ||
445 | if (!tr->allocated_snapshot) { | |
ca268da6 SRRH |
446 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
447 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
448 | tracing_off(); |
449 | return; | |
450 | } | |
451 | ||
452 | /* Note, snapshot can not be used when the tracer uses it */ | |
453 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
454 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
455 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
456 | return; |
457 | } | |
458 | ||
459 | local_irq_save(flags); | |
460 | update_max_tr(tr, current, smp_processor_id()); | |
461 | local_irq_restore(flags); | |
462 | } | |
463 | ||
464 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
465 | struct trace_buffer *size_buf, int cpu_id); | |
466 | ||
467 | /** | |
468 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
469 | * | |
470 | * This is similar to trace_snapshot(), but it will allocate the | |
471 | * snapshot buffer if it isn't already allocated. Use this only | |
472 | * where it is safe to sleep, as the allocation may sleep. | |
473 | * | |
474 | * This causes a swap between the snapshot buffer and the current live | |
475 | * tracing buffer. You can use this to take snapshots of the live | |
476 | * trace when some condition is triggered, but continue to trace. | |
477 | */ | |
478 | void tracing_snapshot_alloc(void) | |
479 | { | |
480 | struct trace_array *tr = &global_trace; | |
481 | int ret; | |
482 | ||
483 | if (!tr->allocated_snapshot) { | |
484 | ||
485 | /* allocate spare buffer */ | |
486 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
487 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
488 | if (WARN_ON(ret < 0)) | |
489 | return; | |
490 | ||
491 | tr->allocated_snapshot = true; | |
492 | } | |
493 | ||
494 | tracing_snapshot(); | |
495 | } | |
496 | #else | |
497 | void tracing_snapshot(void) | |
498 | { | |
499 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
500 | } | |
501 | void tracing_snapshot_alloc(void) | |
502 | { | |
503 | /* Give warning */ | |
504 | tracing_snapshot(); | |
505 | } | |
506 | #endif /* CONFIG_TRACER_SNAPSHOT */ | |
507 | ||
499e5470 SR |
508 | /** |
509 | * tracing_off - turn off tracing buffers | |
510 | * | |
511 | * This function stops the tracing buffers from recording data. | |
512 | * It does not disable any overhead the tracers themselves may | |
513 | * be causing. This function simply causes all recording to | |
514 | * the ring buffers to fail. | |
515 | */ | |
516 | void tracing_off(void) | |
517 | { | |
12883efb SRRH |
518 | if (global_trace.trace_buffer.buffer) |
519 | ring_buffer_record_off(global_trace.trace_buffer.buffer); | |
499e5470 SR |
520 | /* |
521 | * This flag is only looked at when buffers haven't been | |
522 | * allocated yet. We don't really care about the race | |
523 | * between setting this flag and actually turning | |
524 | * on the buffer. | |
525 | */ | |
526 | global_trace.buffer_disabled = 1; | |
527 | } | |
528 | EXPORT_SYMBOL_GPL(tracing_off); | |
529 | ||
530 | /** | |
531 | * tracing_is_on - show state of ring buffers enabled | |
532 | */ | |
533 | int tracing_is_on(void) | |
534 | { | |
12883efb SRRH |
535 | if (global_trace.trace_buffer.buffer) |
536 | return ring_buffer_record_is_on(global_trace.trace_buffer.buffer); | |
499e5470 SR |
537 | return !global_trace.buffer_disabled; |
538 | } | |
539 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
540 | ||
3928a8a2 | 541 | static int __init set_buf_size(char *str) |
bc0c38d1 | 542 | { |
3928a8a2 | 543 | unsigned long buf_size; |
c6caeeb1 | 544 | |
bc0c38d1 SR |
545 | if (!str) |
546 | return 0; | |
9d612bef | 547 | buf_size = memparse(str, &str); |
c6caeeb1 | 548 | /* nr_entries can not be zero */ |
9d612bef | 549 | if (buf_size == 0) |
c6caeeb1 | 550 | return 0; |
3928a8a2 | 551 | trace_buf_size = buf_size; |
bc0c38d1 SR |
552 | return 1; |
553 | } | |
3928a8a2 | 554 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 555 | |
0e950173 TB |
556 | static int __init set_tracing_thresh(char *str) |
557 | { | |
87abb3b1 | 558 | unsigned long threshold; |
0e950173 TB |
559 | int ret; |
560 | ||
561 | if (!str) | |
562 | return 0; | |
bcd83ea6 | 563 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
564 | if (ret < 0) |
565 | return 0; | |
87abb3b1 | 566 | tracing_thresh = threshold * 1000; |
0e950173 TB |
567 | return 1; |
568 | } | |
569 | __setup("tracing_thresh=", set_tracing_thresh); | |
570 | ||
57f50be1 SR |
571 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
572 | { | |
573 | return nsecs / 1000; | |
574 | } | |
575 | ||
4fcdae83 | 576 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
577 | static const char *trace_options[] = { |
578 | "print-parent", | |
579 | "sym-offset", | |
580 | "sym-addr", | |
581 | "verbose", | |
f9896bf3 | 582 | "raw", |
5e3ca0ec | 583 | "hex", |
cb0f12aa | 584 | "bin", |
2a2cc8f7 | 585 | "block", |
86387f7e | 586 | "stacktrace", |
5e1607a0 | 587 | "trace_printk", |
b2a866f9 | 588 | "ftrace_preempt", |
9f029e83 | 589 | "branch", |
12ef7d44 | 590 | "annotate", |
02b67518 | 591 | "userstacktrace", |
b54d3de9 | 592 | "sym-userobj", |
66896a85 | 593 | "printk-msg-only", |
c4a8e8be | 594 | "context-info", |
c032ef64 | 595 | "latency-format", |
be6f164a | 596 | "sleep-time", |
a2a16d6a | 597 | "graph-time", |
e870e9a1 | 598 | "record-cmd", |
750912fa | 599 | "overwrite", |
cf30cf67 | 600 | "disable_on_free", |
77271ce4 | 601 | "irq-info", |
5224c3a3 | 602 | "markers", |
bc0c38d1 SR |
603 | NULL |
604 | }; | |
605 | ||
5079f326 Z |
606 | static struct { |
607 | u64 (*func)(void); | |
608 | const char *name; | |
8be0709f | 609 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 610 | } trace_clocks[] = { |
8be0709f DS |
611 | { trace_clock_local, "local", 1 }, |
612 | { trace_clock_global, "global", 1 }, | |
613 | { trace_clock_counter, "counter", 0 }, | |
8cbd9cc6 | 614 | ARCH_TRACE_CLOCKS |
5079f326 Z |
615 | }; |
616 | ||
617 | int trace_clock_id; | |
618 | ||
b63f39ea | 619 | /* |
620 | * trace_parser_get_init - gets the buffer for trace parser | |
621 | */ | |
622 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
623 | { | |
624 | memset(parser, 0, sizeof(*parser)); | |
625 | ||
626 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
627 | if (!parser->buffer) | |
628 | return 1; | |
629 | ||
630 | parser->size = size; | |
631 | return 0; | |
632 | } | |
633 | ||
634 | /* | |
635 | * trace_parser_put - frees the buffer for trace parser | |
636 | */ | |
637 | void trace_parser_put(struct trace_parser *parser) | |
638 | { | |
639 | kfree(parser->buffer); | |
640 | } | |
641 | ||
642 | /* | |
643 | * trace_get_user - reads the user input string separated by space | |
644 | * (matched by isspace(ch)) | |
645 | * | |
646 | * For each string found the 'struct trace_parser' is updated, | |
647 | * and the function returns. | |
648 | * | |
649 | * Returns number of bytes read. | |
650 | * | |
651 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
652 | */ | |
653 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
654 | size_t cnt, loff_t *ppos) | |
655 | { | |
656 | char ch; | |
657 | size_t read = 0; | |
658 | ssize_t ret; | |
659 | ||
660 | if (!*ppos) | |
661 | trace_parser_clear(parser); | |
662 | ||
663 | ret = get_user(ch, ubuf++); | |
664 | if (ret) | |
665 | goto out; | |
666 | ||
667 | read++; | |
668 | cnt--; | |
669 | ||
670 | /* | |
671 | * The parser is not finished with the last write, | |
672 | * continue reading the user input without skipping spaces. | |
673 | */ | |
674 | if (!parser->cont) { | |
675 | /* skip white space */ | |
676 | while (cnt && isspace(ch)) { | |
677 | ret = get_user(ch, ubuf++); | |
678 | if (ret) | |
679 | goto out; | |
680 | read++; | |
681 | cnt--; | |
682 | } | |
683 | ||
684 | /* only spaces were written */ | |
685 | if (isspace(ch)) { | |
686 | *ppos += read; | |
687 | ret = read; | |
688 | goto out; | |
689 | } | |
690 | ||
691 | parser->idx = 0; | |
692 | } | |
693 | ||
694 | /* read the non-space input */ | |
695 | while (cnt && !isspace(ch)) { | |
3c235a33 | 696 | if (parser->idx < parser->size - 1) |
b63f39ea | 697 | parser->buffer[parser->idx++] = ch; |
698 | else { | |
699 | ret = -EINVAL; | |
700 | goto out; | |
701 | } | |
702 | ret = get_user(ch, ubuf++); | |
703 | if (ret) | |
704 | goto out; | |
705 | read++; | |
706 | cnt--; | |
707 | } | |
708 | ||
709 | /* We either got finished input or we have to wait for another call. */ | |
710 | if (isspace(ch)) { | |
711 | parser->buffer[parser->idx] = 0; | |
712 | parser->cont = false; | |
713 | } else { | |
714 | parser->cont = true; | |
715 | parser->buffer[parser->idx++] = ch; | |
716 | } | |
717 | ||
718 | *ppos += read; | |
719 | ret = read; | |
720 | ||
721 | out: | |
722 | return ret; | |
723 | } | |
724 | ||
6c6c2796 PP |
725 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
726 | { | |
727 | int len; | |
728 | int ret; | |
729 | ||
2dc5d12b SR |
730 | if (!cnt) |
731 | return 0; | |
732 | ||
6c6c2796 PP |
733 | if (s->len <= s->readpos) |
734 | return -EBUSY; | |
735 | ||
736 | len = s->len - s->readpos; | |
737 | if (cnt > len) | |
738 | cnt = len; | |
739 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 740 | if (ret == cnt) |
6c6c2796 PP |
741 | return -EFAULT; |
742 | ||
2dc5d12b SR |
743 | cnt -= ret; |
744 | ||
e74da523 | 745 | s->readpos += cnt; |
6c6c2796 | 746 | return cnt; |
214023c3 SR |
747 | } |
748 | ||
b8b94265 | 749 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
750 | { |
751 | int len; | |
3c56819b EGM |
752 | |
753 | if (s->len <= s->readpos) | |
754 | return -EBUSY; | |
755 | ||
756 | len = s->len - s->readpos; | |
757 | if (cnt > len) | |
758 | cnt = len; | |
5a26c8f0 | 759 | memcpy(buf, s->buffer + s->readpos, cnt); |
3c56819b | 760 | |
e74da523 | 761 | s->readpos += cnt; |
3c56819b EGM |
762 | return cnt; |
763 | } | |
764 | ||
5d4a9dba SR |
765 | /* |
766 | * ftrace_max_lock is used to protect the swapping of buffers | |
767 | * when taking a max snapshot. The buffers themselves are | |
768 | * protected by per_cpu spinlocks. But the action of the swap | |
769 | * needs its own lock. | |
770 | * | |
445c8951 | 771 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
772 | * with performance when lockdep debugging is enabled. |
773 | * | |
774 | * It is also used in other places outside the update_max_tr | |
775 | * so it needs to be defined outside of the | |
776 | * CONFIG_TRACER_MAX_TRACE. | |
777 | */ | |
445c8951 | 778 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 779 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba | 780 | |
0e950173 TB |
781 | unsigned long __read_mostly tracing_thresh; |
782 | ||
5d4a9dba SR |
783 | #ifdef CONFIG_TRACER_MAX_TRACE |
784 | unsigned long __read_mostly tracing_max_latency; | |
5d4a9dba SR |
785 | |
786 | /* | |
787 | * Copy the new maximum trace into the separate maximum-trace | |
788 | * structure. (this way the maximum trace is permanently saved, | |
789 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
790 | */ | |
791 | static void | |
792 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
793 | { | |
12883efb SRRH |
794 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
795 | struct trace_buffer *max_buf = &tr->max_buffer; | |
796 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
797 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 798 | |
12883efb SRRH |
799 | max_buf->cpu = cpu; |
800 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 801 | |
8248ac05 SR |
802 | max_data->saved_latency = tracing_max_latency; |
803 | max_data->critical_start = data->critical_start; | |
804 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 805 | |
1acaa1b2 | 806 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 SR |
807 | max_data->pid = tsk->pid; |
808 | max_data->uid = task_uid(tsk); | |
809 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
810 | max_data->policy = tsk->policy; | |
811 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
812 | |
813 | /* record this tasks comm */ | |
814 | tracing_record_cmdline(tsk); | |
815 | } | |
816 | ||
4fcdae83 SR |
817 | /** |
818 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
819 | * @tr: tracer | |
820 | * @tsk: the task with the latency | |
821 | * @cpu: The cpu that initiated the trace. | |
822 | * | |
823 | * Flip the buffers between the @tr and the max_tr and record information | |
824 | * about which task was the cause of this latency. | |
825 | */ | |
e309b41d | 826 | void |
bc0c38d1 SR |
827 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
828 | { | |
2721e72d | 829 | struct ring_buffer *buf; |
bc0c38d1 | 830 | |
2b6080f2 | 831 | if (tr->stop_count) |
b8de7bd1 SR |
832 | return; |
833 | ||
4c11d7ae | 834 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 835 | |
45ad21ca | 836 | if (!tr->allocated_snapshot) { |
debdd57f | 837 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 838 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 839 | return; |
debdd57f | 840 | } |
34600f0e | 841 | |
0199c4e6 | 842 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 | 843 | |
12883efb SRRH |
844 | buf = tr->trace_buffer.buffer; |
845 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
846 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 847 | |
bc0c38d1 | 848 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 849 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
850 | } |
851 | ||
852 | /** | |
853 | * update_max_tr_single - only copy one trace over, and reset the rest | |
854 | * @tr - tracer | |
855 | * @tsk - task with the latency | |
856 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
857 | * |
858 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 859 | */ |
e309b41d | 860 | void |
bc0c38d1 SR |
861 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
862 | { | |
3928a8a2 | 863 | int ret; |
bc0c38d1 | 864 | |
2b6080f2 | 865 | if (tr->stop_count) |
b8de7bd1 SR |
866 | return; |
867 | ||
4c11d7ae | 868 | WARN_ON_ONCE(!irqs_disabled()); |
45ad21ca | 869 | if (WARN_ON_ONCE(!tr->allocated_snapshot)) |
ef710e10 | 870 | return; |
ef710e10 | 871 | |
0199c4e6 | 872 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 873 | |
12883efb | 874 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 875 | |
e8165dbb SR |
876 | if (ret == -EBUSY) { |
877 | /* | |
878 | * We failed to swap the buffer due to a commit taking | |
879 | * place on this CPU. We fail to record, but we reset | |
880 | * the max trace buffer (no one writes directly to it) | |
881 | * and flag that it failed. | |
882 | */ | |
12883efb | 883 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
884 | "Failed to swap buffers due to commit in progress\n"); |
885 | } | |
886 | ||
e8165dbb | 887 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
888 | |
889 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 890 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 891 | } |
5d4a9dba | 892 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 893 | |
0d5c6e1c SR |
894 | static void default_wait_pipe(struct trace_iterator *iter) |
895 | { | |
15693458 SRRH |
896 | /* Iterators are static, they should be filled or empty */ |
897 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
898 | return; | |
0d5c6e1c | 899 | |
12883efb | 900 | ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file); |
0d5c6e1c SR |
901 | } |
902 | ||
f4e781c0 SRRH |
903 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
904 | static int run_tracer_selftest(struct tracer *type) | |
905 | { | |
906 | struct trace_array *tr = &global_trace; | |
907 | struct tracer *saved_tracer = tr->current_trace; | |
908 | int ret; | |
909 | ||
910 | if (!type->selftest || tracing_selftest_disabled) | |
911 | return 0; | |
912 | ||
913 | /* | |
914 | * Run a selftest on this tracer. | |
915 | * Here we reset the trace buffer, and set the current | |
916 | * tracer to be this tracer. The tracer can then run some | |
917 | * internal tracing to verify that everything is in order. | |
918 | * If we fail, we do not register this tracer. | |
919 | */ | |
920 | tracing_reset_online_cpus(&tr->trace_buffer); | |
921 | ||
922 | tr->current_trace = type; | |
923 | ||
924 | #ifdef CONFIG_TRACER_MAX_TRACE | |
925 | if (type->use_max_tr) { | |
926 | /* If we expanded the buffers, make sure the max is expanded too */ | |
927 | if (ring_buffer_expanded) | |
928 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
929 | RING_BUFFER_ALL_CPUS); | |
930 | tr->allocated_snapshot = true; | |
931 | } | |
932 | #endif | |
933 | ||
934 | /* the test is responsible for initializing and enabling */ | |
935 | pr_info("Testing tracer %s: ", type->name); | |
936 | ret = type->selftest(type, tr); | |
937 | /* the test is responsible for resetting too */ | |
938 | tr->current_trace = saved_tracer; | |
939 | if (ret) { | |
940 | printk(KERN_CONT "FAILED!\n"); | |
941 | /* Add the warning after printing 'FAILED' */ | |
942 | WARN_ON(1); | |
943 | return -1; | |
944 | } | |
945 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
946 | tracing_reset_online_cpus(&tr->trace_buffer); | |
947 | ||
948 | #ifdef CONFIG_TRACER_MAX_TRACE | |
949 | if (type->use_max_tr) { | |
950 | tr->allocated_snapshot = false; | |
951 | ||
952 | /* Shrink the max buffer again */ | |
953 | if (ring_buffer_expanded) | |
954 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
955 | RING_BUFFER_ALL_CPUS); | |
956 | } | |
957 | #endif | |
958 | ||
959 | printk(KERN_CONT "PASSED\n"); | |
960 | return 0; | |
961 | } | |
962 | #else | |
963 | static inline int run_tracer_selftest(struct tracer *type) | |
964 | { | |
965 | return 0; | |
966 | } | |
967 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ | |
968 | ||
4fcdae83 SR |
969 | /** |
970 | * register_tracer - register a tracer with the ftrace system. | |
971 | * @type - the plugin for the tracer | |
972 | * | |
973 | * Register a new plugin tracer. | |
974 | */ | |
bc0c38d1 SR |
975 | int register_tracer(struct tracer *type) |
976 | { | |
977 | struct tracer *t; | |
bc0c38d1 SR |
978 | int ret = 0; |
979 | ||
980 | if (!type->name) { | |
981 | pr_info("Tracer must have a name\n"); | |
982 | return -1; | |
983 | } | |
984 | ||
24a461d5 | 985 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
986 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
987 | return -1; | |
988 | } | |
989 | ||
bc0c38d1 | 990 | mutex_lock(&trace_types_lock); |
86fa2f60 | 991 | |
8e1b82e0 FW |
992 | tracing_selftest_running = true; |
993 | ||
bc0c38d1 SR |
994 | for (t = trace_types; t; t = t->next) { |
995 | if (strcmp(type->name, t->name) == 0) { | |
996 | /* already found */ | |
ee6c2c1b | 997 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
998 | type->name); |
999 | ret = -1; | |
1000 | goto out; | |
1001 | } | |
1002 | } | |
1003 | ||
adf9f195 FW |
1004 | if (!type->set_flag) |
1005 | type->set_flag = &dummy_set_flag; | |
1006 | if (!type->flags) | |
1007 | type->flags = &dummy_tracer_flags; | |
1008 | else | |
1009 | if (!type->flags->opts) | |
1010 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
1011 | if (!type->wait_pipe) |
1012 | type->wait_pipe = default_wait_pipe; | |
1013 | ||
f4e781c0 SRRH |
1014 | ret = run_tracer_selftest(type); |
1015 | if (ret < 0) | |
1016 | goto out; | |
60a11774 | 1017 | |
bc0c38d1 SR |
1018 | type->next = trace_types; |
1019 | trace_types = type; | |
60a11774 | 1020 | |
bc0c38d1 | 1021 | out: |
8e1b82e0 | 1022 | tracing_selftest_running = false; |
bc0c38d1 SR |
1023 | mutex_unlock(&trace_types_lock); |
1024 | ||
dac74940 SR |
1025 | if (ret || !default_bootup_tracer) |
1026 | goto out_unlock; | |
1027 | ||
ee6c2c1b | 1028 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1029 | goto out_unlock; |
1030 | ||
1031 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1032 | /* Do we want this tracer to start on bootup? */ | |
1033 | tracing_set_tracer(type->name); | |
1034 | default_bootup_tracer = NULL; | |
1035 | /* disable other selftests, since this will break it. */ | |
55034cd6 | 1036 | tracing_selftest_disabled = true; |
b2821ae6 | 1037 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1038 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1039 | type->name); | |
b2821ae6 | 1040 | #endif |
b2821ae6 | 1041 | |
dac74940 | 1042 | out_unlock: |
bc0c38d1 SR |
1043 | return ret; |
1044 | } | |
1045 | ||
12883efb | 1046 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1047 | { |
12883efb | 1048 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1049 | |
a5416411 HT |
1050 | if (!buffer) |
1051 | return; | |
1052 | ||
f633903a SR |
1053 | ring_buffer_record_disable(buffer); |
1054 | ||
1055 | /* Make sure all commits have finished */ | |
1056 | synchronize_sched(); | |
68179686 | 1057 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1058 | |
1059 | ring_buffer_record_enable(buffer); | |
1060 | } | |
1061 | ||
12883efb | 1062 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1063 | { |
12883efb | 1064 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1065 | int cpu; |
1066 | ||
a5416411 HT |
1067 | if (!buffer) |
1068 | return; | |
1069 | ||
621968cd SR |
1070 | ring_buffer_record_disable(buffer); |
1071 | ||
1072 | /* Make sure all commits have finished */ | |
1073 | synchronize_sched(); | |
1074 | ||
12883efb | 1075 | buf->time_start = ftrace_now(buf->cpu); |
213cc060 PE |
1076 | |
1077 | for_each_online_cpu(cpu) | |
68179686 | 1078 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1079 | |
1080 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1081 | } |
1082 | ||
9456f0fa SR |
1083 | void tracing_reset_current(int cpu) |
1084 | { | |
12883efb | 1085 | tracing_reset(&global_trace.trace_buffer, cpu); |
9456f0fa SR |
1086 | } |
1087 | ||
873c642f | 1088 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1089 | { |
873c642f SRRH |
1090 | struct trace_array *tr; |
1091 | ||
1092 | mutex_lock(&trace_types_lock); | |
1093 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
12883efb SRRH |
1094 | tracing_reset_online_cpus(&tr->trace_buffer); |
1095 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1096 | tracing_reset_online_cpus(&tr->max_buffer); | |
1097 | #endif | |
873c642f SRRH |
1098 | } |
1099 | mutex_unlock(&trace_types_lock); | |
9456f0fa SR |
1100 | } |
1101 | ||
bc0c38d1 | 1102 | #define SAVED_CMDLINES 128 |
2c7eea4c | 1103 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
1104 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
1105 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
1106 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
1107 | static int cmdline_idx; | |
edc35bd7 | 1108 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 1109 | |
25b0b44a | 1110 | /* temporary disable recording */ |
4fd27358 | 1111 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
1112 | |
1113 | static void trace_init_cmdlines(void) | |
1114 | { | |
2c7eea4c TG |
1115 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
1116 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
1117 | cmdline_idx = 0; |
1118 | } | |
1119 | ||
b5130b1e CE |
1120 | int is_tracing_stopped(void) |
1121 | { | |
2b6080f2 | 1122 | return global_trace.stop_count; |
b5130b1e CE |
1123 | } |
1124 | ||
69bb54ec SR |
1125 | /** |
1126 | * ftrace_off_permanent - disable all ftrace code permanently | |
1127 | * | |
1128 | * This should only be called when a serious anomally has | |
1129 | * been detected. This will turn off the function tracing, | |
1130 | * ring buffers, and other tracing utilites. It takes no | |
1131 | * locks and can be called from any context. | |
1132 | */ | |
1133 | void ftrace_off_permanent(void) | |
1134 | { | |
1135 | tracing_disabled = 1; | |
1136 | ftrace_stop(); | |
1137 | tracing_off_permanent(); | |
1138 | } | |
1139 | ||
0f048701 SR |
1140 | /** |
1141 | * tracing_start - quick start of the tracer | |
1142 | * | |
1143 | * If tracing is enabled but was stopped by tracing_stop, | |
1144 | * this will start the tracer back up. | |
1145 | */ | |
1146 | void tracing_start(void) | |
1147 | { | |
1148 | struct ring_buffer *buffer; | |
1149 | unsigned long flags; | |
1150 | ||
1151 | if (tracing_disabled) | |
1152 | return; | |
1153 | ||
2b6080f2 SR |
1154 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1155 | if (--global_trace.stop_count) { | |
1156 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1157 | /* Someone screwed up their debugging */ |
1158 | WARN_ON_ONCE(1); | |
2b6080f2 | 1159 | global_trace.stop_count = 0; |
b06a8301 | 1160 | } |
0f048701 SR |
1161 | goto out; |
1162 | } | |
1163 | ||
a2f80714 SR |
1164 | /* Prevent the buffers from switching */ |
1165 | arch_spin_lock(&ftrace_max_lock); | |
0f048701 | 1166 | |
12883efb | 1167 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1168 | if (buffer) |
1169 | ring_buffer_record_enable(buffer); | |
1170 | ||
12883efb SRRH |
1171 | #ifdef CONFIG_TRACER_MAX_TRACE |
1172 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1173 | if (buffer) |
1174 | ring_buffer_record_enable(buffer); | |
12883efb | 1175 | #endif |
0f048701 | 1176 | |
a2f80714 SR |
1177 | arch_spin_unlock(&ftrace_max_lock); |
1178 | ||
0f048701 SR |
1179 | ftrace_start(); |
1180 | out: | |
2b6080f2 SR |
1181 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1182 | } | |
1183 | ||
1184 | static void tracing_start_tr(struct trace_array *tr) | |
1185 | { | |
1186 | struct ring_buffer *buffer; | |
1187 | unsigned long flags; | |
1188 | ||
1189 | if (tracing_disabled) | |
1190 | return; | |
1191 | ||
1192 | /* If global, we need to also start the max tracer */ | |
1193 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1194 | return tracing_start(); | |
1195 | ||
1196 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1197 | ||
1198 | if (--tr->stop_count) { | |
1199 | if (tr->stop_count < 0) { | |
1200 | /* Someone screwed up their debugging */ | |
1201 | WARN_ON_ONCE(1); | |
1202 | tr->stop_count = 0; | |
1203 | } | |
1204 | goto out; | |
1205 | } | |
1206 | ||
12883efb | 1207 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1208 | if (buffer) |
1209 | ring_buffer_record_enable(buffer); | |
1210 | ||
1211 | out: | |
1212 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1213 | } |
1214 | ||
1215 | /** | |
1216 | * tracing_stop - quick stop of the tracer | |
1217 | * | |
1218 | * Light weight way to stop tracing. Use in conjunction with | |
1219 | * tracing_start. | |
1220 | */ | |
1221 | void tracing_stop(void) | |
1222 | { | |
1223 | struct ring_buffer *buffer; | |
1224 | unsigned long flags; | |
1225 | ||
1226 | ftrace_stop(); | |
2b6080f2 SR |
1227 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1228 | if (global_trace.stop_count++) | |
0f048701 SR |
1229 | goto out; |
1230 | ||
a2f80714 SR |
1231 | /* Prevent the buffers from switching */ |
1232 | arch_spin_lock(&ftrace_max_lock); | |
1233 | ||
12883efb | 1234 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1235 | if (buffer) |
1236 | ring_buffer_record_disable(buffer); | |
1237 | ||
12883efb SRRH |
1238 | #ifdef CONFIG_TRACER_MAX_TRACE |
1239 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1240 | if (buffer) |
1241 | ring_buffer_record_disable(buffer); | |
12883efb | 1242 | #endif |
0f048701 | 1243 | |
a2f80714 SR |
1244 | arch_spin_unlock(&ftrace_max_lock); |
1245 | ||
0f048701 | 1246 | out: |
2b6080f2 SR |
1247 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1248 | } | |
1249 | ||
1250 | static void tracing_stop_tr(struct trace_array *tr) | |
1251 | { | |
1252 | struct ring_buffer *buffer; | |
1253 | unsigned long flags; | |
1254 | ||
1255 | /* If global, we need to also stop the max tracer */ | |
1256 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1257 | return tracing_stop(); | |
1258 | ||
1259 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1260 | if (tr->stop_count++) | |
1261 | goto out; | |
1262 | ||
12883efb | 1263 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1264 | if (buffer) |
1265 | ring_buffer_record_disable(buffer); | |
1266 | ||
1267 | out: | |
1268 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1269 | } |
1270 | ||
e309b41d | 1271 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1272 | |
e309b41d | 1273 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1274 | { |
a635cf04 | 1275 | unsigned pid, idx; |
bc0c38d1 SR |
1276 | |
1277 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
1278 | return; | |
1279 | ||
1280 | /* | |
1281 | * It's not the end of the world if we don't get | |
1282 | * the lock, but we also don't want to spin | |
1283 | * nor do we want to disable interrupts, | |
1284 | * so if we miss here, then better luck next time. | |
1285 | */ | |
0199c4e6 | 1286 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
1287 | return; |
1288 | ||
1289 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1290 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1291 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1292 | ||
a635cf04 CE |
1293 | /* |
1294 | * Check whether the cmdline buffer at idx has a pid | |
1295 | * mapped. We are going to overwrite that entry so we | |
1296 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1297 | * would read the new comm for the old pid. | |
1298 | */ | |
1299 | pid = map_cmdline_to_pid[idx]; | |
1300 | if (pid != NO_CMDLINE_MAP) | |
1301 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1302 | |
a635cf04 | 1303 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1304 | map_pid_to_cmdline[tsk->pid] = idx; |
1305 | ||
1306 | cmdline_idx = idx; | |
1307 | } | |
1308 | ||
1309 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1310 | ||
0199c4e6 | 1311 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1312 | } |
1313 | ||
4ca53085 | 1314 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1315 | { |
bc0c38d1 SR |
1316 | unsigned map; |
1317 | ||
4ca53085 SR |
1318 | if (!pid) { |
1319 | strcpy(comm, "<idle>"); | |
1320 | return; | |
1321 | } | |
bc0c38d1 | 1322 | |
74bf4076 SR |
1323 | if (WARN_ON_ONCE(pid < 0)) { |
1324 | strcpy(comm, "<XXX>"); | |
1325 | return; | |
1326 | } | |
1327 | ||
4ca53085 SR |
1328 | if (pid > PID_MAX_DEFAULT) { |
1329 | strcpy(comm, "<...>"); | |
1330 | return; | |
1331 | } | |
bc0c38d1 | 1332 | |
5b6045a9 | 1333 | preempt_disable(); |
0199c4e6 | 1334 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1335 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1336 | if (map != NO_CMDLINE_MAP) |
1337 | strcpy(comm, saved_cmdlines[map]); | |
1338 | else | |
1339 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1340 | |
0199c4e6 | 1341 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1342 | preempt_enable(); |
bc0c38d1 SR |
1343 | } |
1344 | ||
e309b41d | 1345 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1346 | { |
0fb9656d | 1347 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1348 | return; |
1349 | ||
7ffbd48d SR |
1350 | if (!__this_cpu_read(trace_cmdline_save)) |
1351 | return; | |
1352 | ||
1353 | __this_cpu_write(trace_cmdline_save, false); | |
1354 | ||
bc0c38d1 SR |
1355 | trace_save_cmdline(tsk); |
1356 | } | |
1357 | ||
45dcd8b8 | 1358 | void |
38697053 SR |
1359 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1360 | int pc) | |
bc0c38d1 SR |
1361 | { |
1362 | struct task_struct *tsk = current; | |
bc0c38d1 | 1363 | |
777e208d SR |
1364 | entry->preempt_count = pc & 0xff; |
1365 | entry->pid = (tsk) ? tsk->pid : 0; | |
1366 | entry->flags = | |
9244489a | 1367 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1368 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1369 | #else |
1370 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1371 | #endif | |
bc0c38d1 SR |
1372 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1373 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1374 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1375 | } | |
f413cdb8 | 1376 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1377 | |
e77405ad SR |
1378 | struct ring_buffer_event * |
1379 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1380 | int type, | |
1381 | unsigned long len, | |
1382 | unsigned long flags, int pc) | |
51a763dd ACM |
1383 | { |
1384 | struct ring_buffer_event *event; | |
1385 | ||
e77405ad | 1386 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1387 | if (event != NULL) { |
1388 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1389 | ||
1390 | tracing_generic_entry_update(ent, flags, pc); | |
1391 | ent->type = type; | |
1392 | } | |
1393 | ||
1394 | return event; | |
1395 | } | |
51a763dd | 1396 | |
7ffbd48d SR |
1397 | void |
1398 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1399 | { | |
1400 | __this_cpu_write(trace_cmdline_save, true); | |
1401 | ring_buffer_unlock_commit(buffer, event); | |
1402 | } | |
1403 | ||
e77405ad SR |
1404 | static inline void |
1405 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1406 | struct ring_buffer_event *event, | |
0d5c6e1c | 1407 | unsigned long flags, int pc) |
51a763dd | 1408 | { |
7ffbd48d | 1409 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1410 | |
e77405ad SR |
1411 | ftrace_trace_stack(buffer, flags, 6, pc); |
1412 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1413 | } |
1414 | ||
e77405ad SR |
1415 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1416 | struct ring_buffer_event *event, | |
1417 | unsigned long flags, int pc) | |
07edf712 | 1418 | { |
0d5c6e1c | 1419 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
51a763dd | 1420 | } |
0d5c6e1c | 1421 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1422 | |
ccb469a1 SR |
1423 | struct ring_buffer_event * |
1424 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
1425 | struct ftrace_event_file *ftrace_file, | |
1426 | int type, unsigned long len, | |
1427 | unsigned long flags, int pc) | |
1428 | { | |
12883efb | 1429 | *current_rb = ftrace_file->tr->trace_buffer.buffer; |
ccb469a1 SR |
1430 | return trace_buffer_lock_reserve(*current_rb, |
1431 | type, len, flags, pc); | |
1432 | } | |
1433 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
1434 | ||
ef5580d0 | 1435 | struct ring_buffer_event * |
e77405ad SR |
1436 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1437 | int type, unsigned long len, | |
ef5580d0 SR |
1438 | unsigned long flags, int pc) |
1439 | { | |
12883efb | 1440 | *current_rb = global_trace.trace_buffer.buffer; |
e77405ad | 1441 | return trace_buffer_lock_reserve(*current_rb, |
ef5580d0 SR |
1442 | type, len, flags, pc); |
1443 | } | |
94487d6d | 1444 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1445 | |
e77405ad SR |
1446 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1447 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1448 | unsigned long flags, int pc) |
1449 | { | |
0d5c6e1c | 1450 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
07edf712 | 1451 | } |
94487d6d | 1452 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1453 | |
0d5c6e1c SR |
1454 | void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1455 | struct ring_buffer_event *event, | |
1456 | unsigned long flags, int pc, | |
1457 | struct pt_regs *regs) | |
1fd8df2c | 1458 | { |
7ffbd48d | 1459 | __buffer_unlock_commit(buffer, event); |
1fd8df2c MH |
1460 | |
1461 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1462 | ftrace_trace_userstack(buffer, flags, pc); | |
1463 | } | |
0d5c6e1c | 1464 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1465 | |
e77405ad SR |
1466 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1467 | struct ring_buffer_event *event) | |
77d9f465 | 1468 | { |
e77405ad | 1469 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1470 | } |
12acd473 | 1471 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1472 | |
e309b41d | 1473 | void |
7be42151 | 1474 | trace_function(struct trace_array *tr, |
38697053 SR |
1475 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1476 | int pc) | |
bc0c38d1 | 1477 | { |
e1112b4d | 1478 | struct ftrace_event_call *call = &event_function; |
12883efb | 1479 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 1480 | struct ring_buffer_event *event; |
777e208d | 1481 | struct ftrace_entry *entry; |
bc0c38d1 | 1482 | |
d769041f | 1483 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1484 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1485 | return; |
1486 | ||
e77405ad | 1487 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1488 | flags, pc); |
3928a8a2 SR |
1489 | if (!event) |
1490 | return; | |
1491 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1492 | entry->ip = ip; |
1493 | entry->parent_ip = parent_ip; | |
e1112b4d | 1494 | |
e77405ad | 1495 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1496 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1497 | } |
1498 | ||
e309b41d | 1499 | void |
2e0f5761 | 1500 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1501 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1502 | int pc) | |
2e0f5761 IM |
1503 | { |
1504 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1505 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1506 | } |
1507 | ||
c0a0d0d3 | 1508 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1509 | |
1510 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1511 | struct ftrace_stack { | |
1512 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1513 | }; | |
1514 | ||
1515 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1516 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1517 | ||
e77405ad | 1518 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1519 | unsigned long flags, |
1fd8df2c | 1520 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1521 | { |
e1112b4d | 1522 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1523 | struct ring_buffer_event *event; |
777e208d | 1524 | struct stack_entry *entry; |
86387f7e | 1525 | struct stack_trace trace; |
4a9bd3f1 SR |
1526 | int use_stack; |
1527 | int size = FTRACE_STACK_ENTRIES; | |
1528 | ||
1529 | trace.nr_entries = 0; | |
1530 | trace.skip = skip; | |
1531 | ||
1532 | /* | |
1533 | * Since events can happen in NMIs there's no safe way to | |
1534 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1535 | * or NMI comes in, it will just have to use the default | |
1536 | * FTRACE_STACK_SIZE. | |
1537 | */ | |
1538 | preempt_disable_notrace(); | |
1539 | ||
82146529 | 1540 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
1541 | /* |
1542 | * We don't need any atomic variables, just a barrier. | |
1543 | * If an interrupt comes in, we don't care, because it would | |
1544 | * have exited and put the counter back to what we want. | |
1545 | * We just need a barrier to keep gcc from moving things | |
1546 | * around. | |
1547 | */ | |
1548 | barrier(); | |
1549 | if (use_stack == 1) { | |
1550 | trace.entries = &__get_cpu_var(ftrace_stack).calls[0]; | |
1551 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; | |
1552 | ||
1553 | if (regs) | |
1554 | save_stack_trace_regs(regs, &trace); | |
1555 | else | |
1556 | save_stack_trace(&trace); | |
1557 | ||
1558 | if (trace.nr_entries > size) | |
1559 | size = trace.nr_entries; | |
1560 | } else | |
1561 | /* From now on, use_stack is a boolean */ | |
1562 | use_stack = 0; | |
1563 | ||
1564 | size *= sizeof(unsigned long); | |
86387f7e | 1565 | |
e77405ad | 1566 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1567 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1568 | if (!event) |
4a9bd3f1 SR |
1569 | goto out; |
1570 | entry = ring_buffer_event_data(event); | |
86387f7e | 1571 | |
4a9bd3f1 SR |
1572 | memset(&entry->caller, 0, size); |
1573 | ||
1574 | if (use_stack) | |
1575 | memcpy(&entry->caller, trace.entries, | |
1576 | trace.nr_entries * sizeof(unsigned long)); | |
1577 | else { | |
1578 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1579 | trace.entries = entry->caller; | |
1580 | if (regs) | |
1581 | save_stack_trace_regs(regs, &trace); | |
1582 | else | |
1583 | save_stack_trace(&trace); | |
1584 | } | |
1585 | ||
1586 | entry->size = trace.nr_entries; | |
86387f7e | 1587 | |
e77405ad | 1588 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1589 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1590 | |
1591 | out: | |
1592 | /* Again, don't let gcc optimize things here */ | |
1593 | barrier(); | |
82146529 | 1594 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
1595 | preempt_enable_notrace(); |
1596 | ||
f0a920d5 IM |
1597 | } |
1598 | ||
1fd8df2c MH |
1599 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1600 | int skip, int pc, struct pt_regs *regs) | |
1601 | { | |
1602 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1603 | return; | |
1604 | ||
1605 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1606 | } | |
1607 | ||
e77405ad SR |
1608 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1609 | int skip, int pc) | |
53614991 SR |
1610 | { |
1611 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1612 | return; | |
1613 | ||
1fd8df2c | 1614 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1615 | } |
1616 | ||
c0a0d0d3 FW |
1617 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1618 | int pc) | |
38697053 | 1619 | { |
12883efb | 1620 | __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); |
38697053 SR |
1621 | } |
1622 | ||
03889384 SR |
1623 | /** |
1624 | * trace_dump_stack - record a stack back trace in the trace buffer | |
1625 | */ | |
1626 | void trace_dump_stack(void) | |
1627 | { | |
1628 | unsigned long flags; | |
1629 | ||
1630 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1631 | return; |
03889384 SR |
1632 | |
1633 | local_save_flags(flags); | |
1634 | ||
1635 | /* skipping 3 traces, seems to get us at the caller of this function */ | |
12883efb SRRH |
1636 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, flags, 3, |
1637 | preempt_count(), NULL); | |
03889384 SR |
1638 | } |
1639 | ||
91e86e56 SR |
1640 | static DEFINE_PER_CPU(int, user_stack_count); |
1641 | ||
e77405ad SR |
1642 | void |
1643 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1644 | { |
e1112b4d | 1645 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1646 | struct ring_buffer_event *event; |
02b67518 TE |
1647 | struct userstack_entry *entry; |
1648 | struct stack_trace trace; | |
02b67518 TE |
1649 | |
1650 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1651 | return; | |
1652 | ||
b6345879 SR |
1653 | /* |
1654 | * NMIs can not handle page faults, even with fix ups. | |
1655 | * The save user stack can (and often does) fault. | |
1656 | */ | |
1657 | if (unlikely(in_nmi())) | |
1658 | return; | |
02b67518 | 1659 | |
91e86e56 SR |
1660 | /* |
1661 | * prevent recursion, since the user stack tracing may | |
1662 | * trigger other kernel events. | |
1663 | */ | |
1664 | preempt_disable(); | |
1665 | if (__this_cpu_read(user_stack_count)) | |
1666 | goto out; | |
1667 | ||
1668 | __this_cpu_inc(user_stack_count); | |
1669 | ||
e77405ad | 1670 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1671 | sizeof(*entry), flags, pc); |
02b67518 | 1672 | if (!event) |
1dbd1951 | 1673 | goto out_drop_count; |
02b67518 | 1674 | entry = ring_buffer_event_data(event); |
02b67518 | 1675 | |
48659d31 | 1676 | entry->tgid = current->tgid; |
02b67518 TE |
1677 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1678 | ||
1679 | trace.nr_entries = 0; | |
1680 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1681 | trace.skip = 0; | |
1682 | trace.entries = entry->caller; | |
1683 | ||
1684 | save_stack_trace_user(&trace); | |
e77405ad | 1685 | if (!filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1686 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1687 | |
1dbd1951 | 1688 | out_drop_count: |
91e86e56 | 1689 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1690 | out: |
1691 | preempt_enable(); | |
02b67518 TE |
1692 | } |
1693 | ||
4fd27358 HE |
1694 | #ifdef UNUSED |
1695 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1696 | { |
7be42151 | 1697 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1698 | } |
4fd27358 | 1699 | #endif /* UNUSED */ |
02b67518 | 1700 | |
c0a0d0d3 FW |
1701 | #endif /* CONFIG_STACKTRACE */ |
1702 | ||
07d777fe SR |
1703 | /* created for use with alloc_percpu */ |
1704 | struct trace_buffer_struct { | |
1705 | char buffer[TRACE_BUF_SIZE]; | |
1706 | }; | |
1707 | ||
1708 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1709 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1710 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1711 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1712 | ||
1713 | /* | |
1714 | * The buffer used is dependent on the context. There is a per cpu | |
1715 | * buffer for normal context, softirq contex, hard irq context and | |
1716 | * for NMI context. Thise allows for lockless recording. | |
1717 | * | |
1718 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1719 | */ | |
1720 | static char *get_trace_buf(void) | |
1721 | { | |
1722 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
1723 | |
1724 | /* | |
1725 | * If we have allocated per cpu buffers, then we do not | |
1726 | * need to do any locking. | |
1727 | */ | |
1728 | if (in_nmi()) | |
1729 | percpu_buffer = trace_percpu_nmi_buffer; | |
1730 | else if (in_irq()) | |
1731 | percpu_buffer = trace_percpu_irq_buffer; | |
1732 | else if (in_softirq()) | |
1733 | percpu_buffer = trace_percpu_sirq_buffer; | |
1734 | else | |
1735 | percpu_buffer = trace_percpu_buffer; | |
1736 | ||
1737 | if (!percpu_buffer) | |
1738 | return NULL; | |
1739 | ||
d8a0349c | 1740 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
1741 | } |
1742 | ||
1743 | static int alloc_percpu_trace_buffer(void) | |
1744 | { | |
1745 | struct trace_buffer_struct *buffers; | |
1746 | struct trace_buffer_struct *sirq_buffers; | |
1747 | struct trace_buffer_struct *irq_buffers; | |
1748 | struct trace_buffer_struct *nmi_buffers; | |
1749 | ||
1750 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1751 | if (!buffers) | |
1752 | goto err_warn; | |
1753 | ||
1754 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1755 | if (!sirq_buffers) | |
1756 | goto err_sirq; | |
1757 | ||
1758 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1759 | if (!irq_buffers) | |
1760 | goto err_irq; | |
1761 | ||
1762 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
1763 | if (!nmi_buffers) | |
1764 | goto err_nmi; | |
1765 | ||
1766 | trace_percpu_buffer = buffers; | |
1767 | trace_percpu_sirq_buffer = sirq_buffers; | |
1768 | trace_percpu_irq_buffer = irq_buffers; | |
1769 | trace_percpu_nmi_buffer = nmi_buffers; | |
1770 | ||
1771 | return 0; | |
1772 | ||
1773 | err_nmi: | |
1774 | free_percpu(irq_buffers); | |
1775 | err_irq: | |
1776 | free_percpu(sirq_buffers); | |
1777 | err_sirq: | |
1778 | free_percpu(buffers); | |
1779 | err_warn: | |
1780 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
1781 | return -ENOMEM; | |
1782 | } | |
1783 | ||
81698831 SR |
1784 | static int buffers_allocated; |
1785 | ||
07d777fe SR |
1786 | void trace_printk_init_buffers(void) |
1787 | { | |
07d777fe SR |
1788 | if (buffers_allocated) |
1789 | return; | |
1790 | ||
1791 | if (alloc_percpu_trace_buffer()) | |
1792 | return; | |
1793 | ||
1794 | pr_info("ftrace: Allocated trace_printk buffers\n"); | |
1795 | ||
b382ede6 SR |
1796 | /* Expand the buffers to set size */ |
1797 | tracing_update_buffers(); | |
1798 | ||
07d777fe | 1799 | buffers_allocated = 1; |
81698831 SR |
1800 | |
1801 | /* | |
1802 | * trace_printk_init_buffers() can be called by modules. | |
1803 | * If that happens, then we need to start cmdline recording | |
1804 | * directly here. If the global_trace.buffer is already | |
1805 | * allocated here, then this was called by module code. | |
1806 | */ | |
12883efb | 1807 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
1808 | tracing_start_cmdline_record(); |
1809 | } | |
1810 | ||
1811 | void trace_printk_start_comm(void) | |
1812 | { | |
1813 | /* Start tracing comms if trace printk is set */ | |
1814 | if (!buffers_allocated) | |
1815 | return; | |
1816 | tracing_start_cmdline_record(); | |
1817 | } | |
1818 | ||
1819 | static void trace_printk_start_stop_comm(int enabled) | |
1820 | { | |
1821 | if (!buffers_allocated) | |
1822 | return; | |
1823 | ||
1824 | if (enabled) | |
1825 | tracing_start_cmdline_record(); | |
1826 | else | |
1827 | tracing_stop_cmdline_record(); | |
07d777fe SR |
1828 | } |
1829 | ||
769b0441 | 1830 | /** |
48ead020 | 1831 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1832 | * |
1833 | */ | |
40ce74f1 | 1834 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1835 | { |
e1112b4d | 1836 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1837 | struct ring_buffer_event *event; |
e77405ad | 1838 | struct ring_buffer *buffer; |
769b0441 | 1839 | struct trace_array *tr = &global_trace; |
48ead020 | 1840 | struct bprint_entry *entry; |
769b0441 | 1841 | unsigned long flags; |
07d777fe SR |
1842 | char *tbuffer; |
1843 | int len = 0, size, pc; | |
769b0441 FW |
1844 | |
1845 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1846 | return 0; | |
1847 | ||
1848 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1849 | pause_graph_tracing(); | |
1850 | ||
1851 | pc = preempt_count(); | |
5168ae50 | 1852 | preempt_disable_notrace(); |
769b0441 | 1853 | |
07d777fe SR |
1854 | tbuffer = get_trace_buf(); |
1855 | if (!tbuffer) { | |
1856 | len = 0; | |
769b0441 | 1857 | goto out; |
07d777fe | 1858 | } |
769b0441 | 1859 | |
07d777fe | 1860 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 1861 | |
07d777fe SR |
1862 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
1863 | goto out; | |
769b0441 | 1864 | |
07d777fe | 1865 | local_save_flags(flags); |
769b0441 | 1866 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 1867 | buffer = tr->trace_buffer.buffer; |
e77405ad SR |
1868 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
1869 | flags, pc); | |
769b0441 | 1870 | if (!event) |
07d777fe | 1871 | goto out; |
769b0441 FW |
1872 | entry = ring_buffer_event_data(event); |
1873 | entry->ip = ip; | |
769b0441 FW |
1874 | entry->fmt = fmt; |
1875 | ||
07d777fe | 1876 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
d931369b | 1877 | if (!filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 1878 | __buffer_unlock_commit(buffer, event); |
d931369b SR |
1879 | ftrace_trace_stack(buffer, flags, 6, pc); |
1880 | } | |
769b0441 | 1881 | |
769b0441 | 1882 | out: |
5168ae50 | 1883 | preempt_enable_notrace(); |
769b0441 FW |
1884 | unpause_graph_tracing(); |
1885 | ||
1886 | return len; | |
1887 | } | |
48ead020 FW |
1888 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1889 | ||
12883efb SRRH |
1890 | static int |
1891 | __trace_array_vprintk(struct ring_buffer *buffer, | |
1892 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 1893 | { |
e1112b4d | 1894 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1895 | struct ring_buffer_event *event; |
07d777fe | 1896 | int len = 0, size, pc; |
48ead020 | 1897 | struct print_entry *entry; |
07d777fe SR |
1898 | unsigned long flags; |
1899 | char *tbuffer; | |
48ead020 FW |
1900 | |
1901 | if (tracing_disabled || tracing_selftest_running) | |
1902 | return 0; | |
1903 | ||
07d777fe SR |
1904 | /* Don't pollute graph traces with trace_vprintk internals */ |
1905 | pause_graph_tracing(); | |
1906 | ||
48ead020 FW |
1907 | pc = preempt_count(); |
1908 | preempt_disable_notrace(); | |
48ead020 | 1909 | |
07d777fe SR |
1910 | |
1911 | tbuffer = get_trace_buf(); | |
1912 | if (!tbuffer) { | |
1913 | len = 0; | |
48ead020 | 1914 | goto out; |
07d777fe | 1915 | } |
48ead020 | 1916 | |
07d777fe SR |
1917 | len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
1918 | if (len > TRACE_BUF_SIZE) | |
1919 | goto out; | |
48ead020 | 1920 | |
07d777fe | 1921 | local_save_flags(flags); |
48ead020 | 1922 | size = sizeof(*entry) + len + 1; |
e77405ad | 1923 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
07d777fe | 1924 | flags, pc); |
48ead020 | 1925 | if (!event) |
07d777fe | 1926 | goto out; |
48ead020 | 1927 | entry = ring_buffer_event_data(event); |
c13d2f7c | 1928 | entry->ip = ip; |
48ead020 | 1929 | |
07d777fe | 1930 | memcpy(&entry->buf, tbuffer, len); |
c13d2f7c | 1931 | entry->buf[len] = '\0'; |
d931369b | 1932 | if (!filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 1933 | __buffer_unlock_commit(buffer, event); |
07d777fe | 1934 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 1935 | } |
48ead020 FW |
1936 | out: |
1937 | preempt_enable_notrace(); | |
07d777fe | 1938 | unpause_graph_tracing(); |
48ead020 FW |
1939 | |
1940 | return len; | |
1941 | } | |
659372d3 | 1942 | |
12883efb SRRH |
1943 | int trace_array_vprintk(struct trace_array *tr, |
1944 | unsigned long ip, const char *fmt, va_list args) | |
1945 | { | |
1946 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
1947 | } | |
1948 | ||
1949 | int trace_array_printk(struct trace_array *tr, | |
1950 | unsigned long ip, const char *fmt, ...) | |
1951 | { | |
1952 | int ret; | |
1953 | va_list ap; | |
1954 | ||
1955 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1956 | return 0; | |
1957 | ||
1958 | va_start(ap, fmt); | |
1959 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
1960 | va_end(ap); | |
1961 | return ret; | |
1962 | } | |
1963 | ||
1964 | int trace_array_printk_buf(struct ring_buffer *buffer, | |
1965 | unsigned long ip, const char *fmt, ...) | |
1966 | { | |
1967 | int ret; | |
1968 | va_list ap; | |
1969 | ||
1970 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1971 | return 0; | |
1972 | ||
1973 | va_start(ap, fmt); | |
1974 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
1975 | va_end(ap); | |
1976 | return ret; | |
1977 | } | |
1978 | ||
659372d3 SR |
1979 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
1980 | { | |
a813a159 | 1981 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 1982 | } |
769b0441 FW |
1983 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1984 | ||
e2ac8ef5 | 1985 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1986 | { |
6d158a81 SR |
1987 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
1988 | ||
5a90f577 | 1989 | iter->idx++; |
6d158a81 SR |
1990 | if (buf_iter) |
1991 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
1992 | } |
1993 | ||
e309b41d | 1994 | static struct trace_entry * |
bc21b478 SR |
1995 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
1996 | unsigned long *lost_events) | |
dd0e545f | 1997 | { |
3928a8a2 | 1998 | struct ring_buffer_event *event; |
6d158a81 | 1999 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 2000 | |
d769041f SR |
2001 | if (buf_iter) |
2002 | event = ring_buffer_iter_peek(buf_iter, ts); | |
2003 | else | |
12883efb | 2004 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 2005 | lost_events); |
d769041f | 2006 | |
4a9bd3f1 SR |
2007 | if (event) { |
2008 | iter->ent_size = ring_buffer_event_length(event); | |
2009 | return ring_buffer_event_data(event); | |
2010 | } | |
2011 | iter->ent_size = 0; | |
2012 | return NULL; | |
dd0e545f | 2013 | } |
d769041f | 2014 | |
dd0e545f | 2015 | static struct trace_entry * |
bc21b478 SR |
2016 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
2017 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 2018 | { |
12883efb | 2019 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 2020 | struct trace_entry *ent, *next = NULL; |
aa27497c | 2021 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 2022 | int cpu_file = iter->cpu_file; |
3928a8a2 | 2023 | u64 next_ts = 0, ts; |
bc0c38d1 | 2024 | int next_cpu = -1; |
12b5da34 | 2025 | int next_size = 0; |
bc0c38d1 SR |
2026 | int cpu; |
2027 | ||
b04cc6b1 FW |
2028 | /* |
2029 | * If we are in a per_cpu trace file, don't bother by iterating over | |
2030 | * all cpu and peek directly. | |
2031 | */ | |
ae3b5093 | 2032 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
2033 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
2034 | return NULL; | |
bc21b478 | 2035 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
2036 | if (ent_cpu) |
2037 | *ent_cpu = cpu_file; | |
2038 | ||
2039 | return ent; | |
2040 | } | |
2041 | ||
ab46428c | 2042 | for_each_tracing_cpu(cpu) { |
dd0e545f | 2043 | |
3928a8a2 SR |
2044 | if (ring_buffer_empty_cpu(buffer, cpu)) |
2045 | continue; | |
dd0e545f | 2046 | |
bc21b478 | 2047 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 2048 | |
cdd31cd2 IM |
2049 | /* |
2050 | * Pick the entry with the smallest timestamp: | |
2051 | */ | |
3928a8a2 | 2052 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
2053 | next = ent; |
2054 | next_cpu = cpu; | |
3928a8a2 | 2055 | next_ts = ts; |
bc21b478 | 2056 | next_lost = lost_events; |
12b5da34 | 2057 | next_size = iter->ent_size; |
bc0c38d1 SR |
2058 | } |
2059 | } | |
2060 | ||
12b5da34 SR |
2061 | iter->ent_size = next_size; |
2062 | ||
bc0c38d1 SR |
2063 | if (ent_cpu) |
2064 | *ent_cpu = next_cpu; | |
2065 | ||
3928a8a2 SR |
2066 | if (ent_ts) |
2067 | *ent_ts = next_ts; | |
2068 | ||
bc21b478 SR |
2069 | if (missing_events) |
2070 | *missing_events = next_lost; | |
2071 | ||
bc0c38d1 SR |
2072 | return next; |
2073 | } | |
2074 | ||
dd0e545f | 2075 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
2076 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
2077 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 2078 | { |
bc21b478 | 2079 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
2080 | } |
2081 | ||
2082 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 2083 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 2084 | { |
bc21b478 SR |
2085 | iter->ent = __find_next_entry(iter, &iter->cpu, |
2086 | &iter->lost_events, &iter->ts); | |
dd0e545f | 2087 | |
3928a8a2 | 2088 | if (iter->ent) |
e2ac8ef5 | 2089 | trace_iterator_increment(iter); |
dd0e545f | 2090 | |
3928a8a2 | 2091 | return iter->ent ? iter : NULL; |
b3806b43 | 2092 | } |
bc0c38d1 | 2093 | |
e309b41d | 2094 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 2095 | { |
12883efb | 2096 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 2097 | &iter->lost_events); |
bc0c38d1 SR |
2098 | } |
2099 | ||
e309b41d | 2100 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
2101 | { |
2102 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 2103 | int i = (int)*pos; |
4e3c3333 | 2104 | void *ent; |
bc0c38d1 | 2105 | |
a63ce5b3 SR |
2106 | WARN_ON_ONCE(iter->leftover); |
2107 | ||
bc0c38d1 SR |
2108 | (*pos)++; |
2109 | ||
2110 | /* can't go backwards */ | |
2111 | if (iter->idx > i) | |
2112 | return NULL; | |
2113 | ||
2114 | if (iter->idx < 0) | |
955b61e5 | 2115 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2116 | else |
2117 | ent = iter; | |
2118 | ||
2119 | while (ent && iter->idx < i) | |
955b61e5 | 2120 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2121 | |
2122 | iter->pos = *pos; | |
2123 | ||
bc0c38d1 SR |
2124 | return ent; |
2125 | } | |
2126 | ||
955b61e5 | 2127 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 2128 | { |
2f26ebd5 SR |
2129 | struct ring_buffer_event *event; |
2130 | struct ring_buffer_iter *buf_iter; | |
2131 | unsigned long entries = 0; | |
2132 | u64 ts; | |
2133 | ||
12883efb | 2134 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 2135 | |
6d158a81 SR |
2136 | buf_iter = trace_buffer_iter(iter, cpu); |
2137 | if (!buf_iter) | |
2f26ebd5 SR |
2138 | return; |
2139 | ||
2f26ebd5 SR |
2140 | ring_buffer_iter_reset(buf_iter); |
2141 | ||
2142 | /* | |
2143 | * We could have the case with the max latency tracers | |
2144 | * that a reset never took place on a cpu. This is evident | |
2145 | * by the timestamp being before the start of the buffer. | |
2146 | */ | |
2147 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 2148 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
2149 | break; |
2150 | entries++; | |
2151 | ring_buffer_read(buf_iter, NULL); | |
2152 | } | |
2153 | ||
12883efb | 2154 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2155 | } |
2156 | ||
d7350c3f | 2157 | /* |
d7350c3f FW |
2158 | * The current tracer is copied to avoid a global locking |
2159 | * all around. | |
2160 | */ | |
bc0c38d1 SR |
2161 | static void *s_start(struct seq_file *m, loff_t *pos) |
2162 | { | |
2163 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2164 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2165 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2166 | void *p = NULL; |
2167 | loff_t l = 0; | |
3928a8a2 | 2168 | int cpu; |
bc0c38d1 | 2169 | |
2fd196ec HT |
2170 | /* |
2171 | * copy the tracer to avoid using a global lock all around. | |
2172 | * iter->trace is a copy of current_trace, the pointer to the | |
2173 | * name may be used instead of a strcmp(), as iter->trace->name | |
2174 | * will point to the same string as current_trace->name. | |
2175 | */ | |
bc0c38d1 | 2176 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2177 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2178 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2179 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2180 | |
12883efb | 2181 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2182 | if (iter->snapshot && iter->trace->use_max_tr) |
2183 | return ERR_PTR(-EBUSY); | |
12883efb | 2184 | #endif |
debdd57f HT |
2185 | |
2186 | if (!iter->snapshot) | |
2187 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2188 | |
bc0c38d1 SR |
2189 | if (*pos != iter->pos) { |
2190 | iter->ent = NULL; | |
2191 | iter->cpu = 0; | |
2192 | iter->idx = -1; | |
2193 | ||
ae3b5093 | 2194 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2195 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2196 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2197 | } else |
2f26ebd5 | 2198 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2199 | |
ac91d854 | 2200 | iter->leftover = 0; |
bc0c38d1 SR |
2201 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2202 | ; | |
2203 | ||
2204 | } else { | |
a63ce5b3 SR |
2205 | /* |
2206 | * If we overflowed the seq_file before, then we want | |
2207 | * to just reuse the trace_seq buffer again. | |
2208 | */ | |
2209 | if (iter->leftover) | |
2210 | p = iter; | |
2211 | else { | |
2212 | l = *pos - 1; | |
2213 | p = s_next(m, p, &l); | |
2214 | } | |
bc0c38d1 SR |
2215 | } |
2216 | ||
4f535968 | 2217 | trace_event_read_lock(); |
7e53bd42 | 2218 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2219 | return p; |
2220 | } | |
2221 | ||
2222 | static void s_stop(struct seq_file *m, void *p) | |
2223 | { | |
7e53bd42 LJ |
2224 | struct trace_iterator *iter = m->private; |
2225 | ||
12883efb | 2226 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2227 | if (iter->snapshot && iter->trace->use_max_tr) |
2228 | return; | |
12883efb | 2229 | #endif |
debdd57f HT |
2230 | |
2231 | if (!iter->snapshot) | |
2232 | atomic_dec(&trace_record_cmdline_disabled); | |
12883efb | 2233 | |
7e53bd42 | 2234 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2235 | trace_event_read_unlock(); |
bc0c38d1 SR |
2236 | } |
2237 | ||
39eaf7ef | 2238 | static void |
12883efb SRRH |
2239 | get_total_entries(struct trace_buffer *buf, |
2240 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
2241 | { |
2242 | unsigned long count; | |
2243 | int cpu; | |
2244 | ||
2245 | *total = 0; | |
2246 | *entries = 0; | |
2247 | ||
2248 | for_each_tracing_cpu(cpu) { | |
12883efb | 2249 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2250 | /* |
2251 | * If this buffer has skipped entries, then we hold all | |
2252 | * entries for the trace and we need to ignore the | |
2253 | * ones before the time stamp. | |
2254 | */ | |
12883efb SRRH |
2255 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
2256 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2257 | /* total is the same as the entries */ |
2258 | *total += count; | |
2259 | } else | |
2260 | *total += count + | |
12883efb | 2261 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2262 | *entries += count; |
2263 | } | |
2264 | } | |
2265 | ||
e309b41d | 2266 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2267 | { |
a6168353 ME |
2268 | seq_puts(m, "# _------=> CPU# \n"); |
2269 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
2270 | seq_puts(m, "# | / _----=> need-resched \n"); | |
2271 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
2272 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
2273 | seq_puts(m, "# |||| / delay \n"); |
2274 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
2275 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2276 | } |
2277 | ||
12883efb | 2278 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 2279 | { |
39eaf7ef SR |
2280 | unsigned long total; |
2281 | unsigned long entries; | |
2282 | ||
12883efb | 2283 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
2284 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
2285 | entries, total, num_online_cpus()); | |
2286 | seq_puts(m, "#\n"); | |
2287 | } | |
2288 | ||
12883efb | 2289 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) |
39eaf7ef | 2290 | { |
12883efb | 2291 | print_event_info(buf, m); |
77271ce4 | 2292 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
a6168353 | 2293 | seq_puts(m, "# | | | | |\n"); |
bc0c38d1 SR |
2294 | } |
2295 | ||
12883efb | 2296 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) |
77271ce4 | 2297 | { |
12883efb | 2298 | print_event_info(buf, m); |
77271ce4 SR |
2299 | seq_puts(m, "# _-----=> irqs-off\n"); |
2300 | seq_puts(m, "# / _----=> need-resched\n"); | |
2301 | seq_puts(m, "# | / _---=> hardirq/softirq\n"); | |
2302 | seq_puts(m, "# || / _--=> preempt-depth\n"); | |
2303 | seq_puts(m, "# ||| / delay\n"); | |
2304 | seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); | |
2305 | seq_puts(m, "# | | | |||| | |\n"); | |
2306 | } | |
bc0c38d1 | 2307 | |
62b915f1 | 2308 | void |
bc0c38d1 SR |
2309 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2310 | { | |
2311 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
12883efb SRRH |
2312 | struct trace_buffer *buf = iter->trace_buffer; |
2313 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 2314 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2315 | unsigned long entries; |
2316 | unsigned long total; | |
bc0c38d1 SR |
2317 | const char *name = "preemption"; |
2318 | ||
d840f718 | 2319 | name = type->name; |
bc0c38d1 | 2320 | |
12883efb | 2321 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 2322 | |
888b55dc | 2323 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2324 | name, UTS_RELEASE); |
888b55dc | 2325 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2326 | "---------------------------------\n"); |
888b55dc | 2327 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2328 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2329 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2330 | entries, |
4c11d7ae | 2331 | total, |
12883efb | 2332 | buf->cpu, |
bc0c38d1 SR |
2333 | #if defined(CONFIG_PREEMPT_NONE) |
2334 | "server", | |
2335 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2336 | "desktop", | |
b5c21b45 | 2337 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2338 | "preempt", |
2339 | #else | |
2340 | "unknown", | |
2341 | #endif | |
2342 | /* These are reserved for later use */ | |
2343 | 0, 0, 0, 0); | |
2344 | #ifdef CONFIG_SMP | |
2345 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2346 | #else | |
2347 | seq_puts(m, ")\n"); | |
2348 | #endif | |
888b55dc KM |
2349 | seq_puts(m, "# -----------------\n"); |
2350 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2351 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2352 | data->comm, data->pid, |
2353 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2354 | data->policy, data->rt_priority); |
888b55dc | 2355 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2356 | |
2357 | if (data->critical_start) { | |
888b55dc | 2358 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2359 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2360 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2361 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2362 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2363 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2364 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2365 | } |
2366 | ||
888b55dc | 2367 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2368 | } |
2369 | ||
a309720c SR |
2370 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2371 | { | |
2372 | struct trace_seq *s = &iter->seq; | |
2373 | ||
12ef7d44 SR |
2374 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2375 | return; | |
2376 | ||
2377 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2378 | return; | |
2379 | ||
4462344e | 2380 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2381 | return; |
2382 | ||
12883efb | 2383 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
2384 | return; |
2385 | ||
4462344e | 2386 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2387 | |
2388 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2389 | if (iter->idx > 1) | |
2390 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2391 | iter->cpu); | |
a309720c SR |
2392 | } |
2393 | ||
2c4f035f | 2394 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2395 | { |
214023c3 | 2396 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2397 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2398 | struct trace_entry *entry; |
f633cef0 | 2399 | struct trace_event *event; |
bc0c38d1 | 2400 | |
4e3c3333 | 2401 | entry = iter->ent; |
dd0e545f | 2402 | |
a309720c SR |
2403 | test_cpu_buff_start(iter); |
2404 | ||
c4a8e8be | 2405 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2406 | |
c4a8e8be | 2407 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
2408 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2409 | if (!trace_print_lat_context(iter)) | |
2410 | goto partial; | |
2411 | } else { | |
2412 | if (!trace_print_context(iter)) | |
2413 | goto partial; | |
2414 | } | |
c4a8e8be | 2415 | } |
bc0c38d1 | 2416 | |
268ccda0 | 2417 | if (event) |
a9a57763 | 2418 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
2419 | |
2420 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
2421 | goto partial; | |
02b67518 | 2422 | |
2c4f035f | 2423 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2424 | partial: |
2425 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
2426 | } |
2427 | ||
2c4f035f | 2428 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2429 | { |
2430 | struct trace_seq *s = &iter->seq; | |
2431 | struct trace_entry *entry; | |
f633cef0 | 2432 | struct trace_event *event; |
f9896bf3 IM |
2433 | |
2434 | entry = iter->ent; | |
dd0e545f | 2435 | |
c4a8e8be | 2436 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
2437 | if (!trace_seq_printf(s, "%d %d %llu ", |
2438 | entry->pid, iter->cpu, iter->ts)) | |
2439 | goto partial; | |
c4a8e8be | 2440 | } |
f9896bf3 | 2441 | |
f633cef0 | 2442 | event = ftrace_find_event(entry->type); |
268ccda0 | 2443 | if (event) |
a9a57763 | 2444 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
2445 | |
2446 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
2447 | goto partial; | |
777e208d | 2448 | |
2c4f035f | 2449 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2450 | partial: |
2451 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
2452 | } |
2453 | ||
2c4f035f | 2454 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2455 | { |
2456 | struct trace_seq *s = &iter->seq; | |
2457 | unsigned char newline = '\n'; | |
2458 | struct trace_entry *entry; | |
f633cef0 | 2459 | struct trace_event *event; |
5e3ca0ec IM |
2460 | |
2461 | entry = iter->ent; | |
dd0e545f | 2462 | |
c4a8e8be FW |
2463 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2464 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
2465 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
2466 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
2467 | } | |
5e3ca0ec | 2468 | |
f633cef0 | 2469 | event = ftrace_find_event(entry->type); |
268ccda0 | 2470 | if (event) { |
a9a57763 | 2471 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2472 | if (ret != TRACE_TYPE_HANDLED) |
2473 | return ret; | |
2474 | } | |
7104f300 | 2475 | |
5e3ca0ec IM |
2476 | SEQ_PUT_FIELD_RET(s, newline); |
2477 | ||
2c4f035f | 2478 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
2479 | } |
2480 | ||
2c4f035f | 2481 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2482 | { |
2483 | struct trace_seq *s = &iter->seq; | |
2484 | struct trace_entry *entry; | |
f633cef0 | 2485 | struct trace_event *event; |
cb0f12aa IM |
2486 | |
2487 | entry = iter->ent; | |
dd0e545f | 2488 | |
c4a8e8be FW |
2489 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2490 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 2491 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2492 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2493 | } | |
cb0f12aa | 2494 | |
f633cef0 | 2495 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2496 | return event ? event->funcs->binary(iter, 0, event) : |
2497 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2498 | } |
2499 | ||
62b915f1 | 2500 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2501 | { |
6d158a81 | 2502 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2503 | int cpu; |
2504 | ||
9aba60fe | 2505 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 2506 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 2507 | cpu = iter->cpu_file; |
6d158a81 SR |
2508 | buf_iter = trace_buffer_iter(iter, cpu); |
2509 | if (buf_iter) { | |
2510 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2511 | return 0; |
2512 | } else { | |
12883efb | 2513 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
2514 | return 0; |
2515 | } | |
2516 | return 1; | |
2517 | } | |
2518 | ||
ab46428c | 2519 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2520 | buf_iter = trace_buffer_iter(iter, cpu); |
2521 | if (buf_iter) { | |
2522 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2523 | return 0; |
2524 | } else { | |
12883efb | 2525 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
2526 | return 0; |
2527 | } | |
bc0c38d1 | 2528 | } |
d769041f | 2529 | |
797d3712 | 2530 | return 1; |
bc0c38d1 SR |
2531 | } |
2532 | ||
4f535968 | 2533 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2534 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2535 | { |
2c4f035f FW |
2536 | enum print_line_t ret; |
2537 | ||
ee5e51f5 JO |
2538 | if (iter->lost_events && |
2539 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2540 | iter->cpu, iter->lost_events)) | |
2541 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2542 | |
2c4f035f FW |
2543 | if (iter->trace && iter->trace->print_line) { |
2544 | ret = iter->trace->print_line(iter); | |
2545 | if (ret != TRACE_TYPE_UNHANDLED) | |
2546 | return ret; | |
2547 | } | |
72829bc3 | 2548 | |
09ae7234 SRRH |
2549 | if (iter->ent->type == TRACE_BPUTS && |
2550 | trace_flags & TRACE_ITER_PRINTK && | |
2551 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
2552 | return trace_print_bputs_msg_only(iter); | |
2553 | ||
48ead020 FW |
2554 | if (iter->ent->type == TRACE_BPRINT && |
2555 | trace_flags & TRACE_ITER_PRINTK && | |
2556 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2557 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2558 | |
66896a85 FW |
2559 | if (iter->ent->type == TRACE_PRINT && |
2560 | trace_flags & TRACE_ITER_PRINTK && | |
2561 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2562 | return trace_print_printk_msg_only(iter); |
66896a85 | 2563 | |
cb0f12aa IM |
2564 | if (trace_flags & TRACE_ITER_BIN) |
2565 | return print_bin_fmt(iter); | |
2566 | ||
5e3ca0ec IM |
2567 | if (trace_flags & TRACE_ITER_HEX) |
2568 | return print_hex_fmt(iter); | |
2569 | ||
f9896bf3 IM |
2570 | if (trace_flags & TRACE_ITER_RAW) |
2571 | return print_raw_fmt(iter); | |
2572 | ||
f9896bf3 IM |
2573 | return print_trace_fmt(iter); |
2574 | } | |
2575 | ||
7e9a49ef JO |
2576 | void trace_latency_header(struct seq_file *m) |
2577 | { | |
2578 | struct trace_iterator *iter = m->private; | |
2579 | ||
2580 | /* print nothing if the buffers are empty */ | |
2581 | if (trace_empty(iter)) | |
2582 | return; | |
2583 | ||
2584 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2585 | print_trace_header(m, iter); | |
2586 | ||
2587 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2588 | print_lat_help_header(m); | |
2589 | } | |
2590 | ||
62b915f1 JO |
2591 | void trace_default_header(struct seq_file *m) |
2592 | { | |
2593 | struct trace_iterator *iter = m->private; | |
2594 | ||
f56e7f8e JO |
2595 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2596 | return; | |
2597 | ||
62b915f1 JO |
2598 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2599 | /* print nothing if the buffers are empty */ | |
2600 | if (trace_empty(iter)) | |
2601 | return; | |
2602 | print_trace_header(m, iter); | |
2603 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2604 | print_lat_help_header(m); | |
2605 | } else { | |
77271ce4 SR |
2606 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2607 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
12883efb | 2608 | print_func_help_header_irq(iter->trace_buffer, m); |
77271ce4 | 2609 | else |
12883efb | 2610 | print_func_help_header(iter->trace_buffer, m); |
77271ce4 | 2611 | } |
62b915f1 JO |
2612 | } |
2613 | } | |
2614 | ||
e0a413f6 SR |
2615 | static void test_ftrace_alive(struct seq_file *m) |
2616 | { | |
2617 | if (!ftrace_is_dead()) | |
2618 | return; | |
2619 | seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
2620 | seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n"); | |
2621 | } | |
2622 | ||
d8741e2e | 2623 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa SRRH |
2624 | static void show_snapshot_main_help(struct seq_file *m) |
2625 | { | |
2626 | seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n"); | |
2627 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2628 | seq_printf(m, "# Takes a snapshot of the main buffer.\n"); | |
2629 | seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate)\n"); | |
2630 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); | |
2631 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2632 | } | |
2633 | ||
2634 | static void show_snapshot_percpu_help(struct seq_file *m) | |
2635 | { | |
2636 | seq_printf(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); | |
2637 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP | |
2638 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2639 | seq_printf(m, "# Takes a snapshot of the main buffer for this cpu.\n"); | |
2640 | #else | |
2641 | seq_printf(m, "# echo 1 > snapshot : Not supported with this kernel.\n"); | |
2642 | seq_printf(m, "# Must use main snapshot file to allocate.\n"); | |
2643 | #endif | |
2644 | seq_printf(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n"); | |
2645 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); | |
2646 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2647 | } | |
2648 | ||
d8741e2e SRRH |
2649 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
2650 | { | |
45ad21ca | 2651 | if (iter->tr->allocated_snapshot) |
d8741e2e SRRH |
2652 | seq_printf(m, "#\n# * Snapshot is allocated *\n#\n"); |
2653 | else | |
2654 | seq_printf(m, "#\n# * Snapshot is freed *\n#\n"); | |
2655 | ||
2656 | seq_printf(m, "# Snapshot commands:\n"); | |
f1affcaa SRRH |
2657 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
2658 | show_snapshot_main_help(m); | |
2659 | else | |
2660 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
2661 | } |
2662 | #else | |
2663 | /* Should never be called */ | |
2664 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
2665 | #endif | |
2666 | ||
bc0c38d1 SR |
2667 | static int s_show(struct seq_file *m, void *v) |
2668 | { | |
2669 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2670 | int ret; |
bc0c38d1 SR |
2671 | |
2672 | if (iter->ent == NULL) { | |
2673 | if (iter->tr) { | |
2674 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2675 | seq_puts(m, "#\n"); | |
e0a413f6 | 2676 | test_ftrace_alive(m); |
bc0c38d1 | 2677 | } |
d8741e2e SRRH |
2678 | if (iter->snapshot && trace_empty(iter)) |
2679 | print_snapshot_help(m, iter); | |
2680 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 2681 | iter->trace->print_header(m); |
62b915f1 JO |
2682 | else |
2683 | trace_default_header(m); | |
2684 | ||
a63ce5b3 SR |
2685 | } else if (iter->leftover) { |
2686 | /* | |
2687 | * If we filled the seq_file buffer earlier, we | |
2688 | * want to just show it now. | |
2689 | */ | |
2690 | ret = trace_print_seq(m, &iter->seq); | |
2691 | ||
2692 | /* ret should this time be zero, but you never know */ | |
2693 | iter->leftover = ret; | |
2694 | ||
bc0c38d1 | 2695 | } else { |
f9896bf3 | 2696 | print_trace_line(iter); |
a63ce5b3 SR |
2697 | ret = trace_print_seq(m, &iter->seq); |
2698 | /* | |
2699 | * If we overflow the seq_file buffer, then it will | |
2700 | * ask us for this data again at start up. | |
2701 | * Use that instead. | |
2702 | * ret is 0 if seq_file write succeeded. | |
2703 | * -1 otherwise. | |
2704 | */ | |
2705 | iter->leftover = ret; | |
bc0c38d1 SR |
2706 | } |
2707 | ||
2708 | return 0; | |
2709 | } | |
2710 | ||
88e9d34c | 2711 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2712 | .start = s_start, |
2713 | .next = s_next, | |
2714 | .stop = s_stop, | |
2715 | .show = s_show, | |
bc0c38d1 SR |
2716 | }; |
2717 | ||
e309b41d | 2718 | static struct trace_iterator * |
debdd57f | 2719 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 2720 | { |
2b6080f2 SR |
2721 | struct trace_cpu *tc = inode->i_private; |
2722 | struct trace_array *tr = tc->tr; | |
bc0c38d1 | 2723 | struct trace_iterator *iter; |
50e18b94 | 2724 | int cpu; |
bc0c38d1 | 2725 | |
85a2f9b4 SR |
2726 | if (tracing_disabled) |
2727 | return ERR_PTR(-ENODEV); | |
60a11774 | 2728 | |
50e18b94 | 2729 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2730 | if (!iter) |
2731 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2732 | |
6d158a81 SR |
2733 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
2734 | GFP_KERNEL); | |
93574fcc DC |
2735 | if (!iter->buffer_iter) |
2736 | goto release; | |
2737 | ||
d7350c3f FW |
2738 | /* |
2739 | * We make a copy of the current tracer to avoid concurrent | |
2740 | * changes on it while we are reading. | |
2741 | */ | |
bc0c38d1 | 2742 | mutex_lock(&trace_types_lock); |
d7350c3f | 2743 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2744 | if (!iter->trace) |
d7350c3f | 2745 | goto fail; |
85a2f9b4 | 2746 | |
2b6080f2 | 2747 | *iter->trace = *tr->current_trace; |
d7350c3f | 2748 | |
79f55997 | 2749 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2750 | goto fail; |
2751 | ||
12883efb SRRH |
2752 | iter->tr = tr; |
2753 | ||
2754 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
2755 | /* Currently only the top directory has a snapshot */ |
2756 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 2757 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 2758 | else |
12883efb SRRH |
2759 | #endif |
2760 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 2761 | iter->snapshot = snapshot; |
bc0c38d1 | 2762 | iter->pos = -1; |
d7350c3f | 2763 | mutex_init(&iter->mutex); |
2b6080f2 | 2764 | iter->cpu_file = tc->cpu; |
bc0c38d1 | 2765 | |
8bba1bf5 MM |
2766 | /* Notify the tracer early; before we stop tracing. */ |
2767 | if (iter->trace && iter->trace->open) | |
a93751ca | 2768 | iter->trace->open(iter); |
8bba1bf5 | 2769 | |
12ef7d44 | 2770 | /* Annotate start of buffers if we had overruns */ |
12883efb | 2771 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
2772 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
2773 | ||
8be0709f DS |
2774 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
2775 | if (trace_clocks[trace_clock_id].in_ns) | |
2776 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
2777 | ||
debdd57f HT |
2778 | /* stop the trace while dumping if we are not opening "snapshot" */ |
2779 | if (!iter->snapshot) | |
2b6080f2 | 2780 | tracing_stop_tr(tr); |
2f26ebd5 | 2781 | |
ae3b5093 | 2782 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2783 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 2784 | iter->buffer_iter[cpu] = |
12883efb | 2785 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
2786 | } |
2787 | ring_buffer_read_prepare_sync(); | |
2788 | for_each_tracing_cpu(cpu) { | |
2789 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2790 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2791 | } |
2792 | } else { | |
2793 | cpu = iter->cpu_file; | |
3928a8a2 | 2794 | iter->buffer_iter[cpu] = |
12883efb | 2795 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
2796 | ring_buffer_read_prepare_sync(); |
2797 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2798 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2799 | } |
2800 | ||
a695cb58 SRRH |
2801 | tr->ref++; |
2802 | ||
bc0c38d1 SR |
2803 | mutex_unlock(&trace_types_lock); |
2804 | ||
bc0c38d1 | 2805 | return iter; |
3928a8a2 | 2806 | |
d7350c3f | 2807 | fail: |
3928a8a2 | 2808 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2809 | kfree(iter->trace); |
6d158a81 | 2810 | kfree(iter->buffer_iter); |
93574fcc | 2811 | release: |
50e18b94 JO |
2812 | seq_release_private(inode, file); |
2813 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
2814 | } |
2815 | ||
2816 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2817 | { | |
60a11774 SR |
2818 | if (tracing_disabled) |
2819 | return -ENODEV; | |
2820 | ||
bc0c38d1 SR |
2821 | filp->private_data = inode->i_private; |
2822 | return 0; | |
2823 | } | |
2824 | ||
4fd27358 | 2825 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 2826 | { |
907f2784 | 2827 | struct seq_file *m = file->private_data; |
4acd4d00 | 2828 | struct trace_iterator *iter; |
2b6080f2 | 2829 | struct trace_array *tr; |
3928a8a2 | 2830 | int cpu; |
bc0c38d1 | 2831 | |
4acd4d00 SR |
2832 | if (!(file->f_mode & FMODE_READ)) |
2833 | return 0; | |
2834 | ||
2835 | iter = m->private; | |
12883efb | 2836 | tr = iter->tr; |
2b6080f2 | 2837 | |
bc0c38d1 | 2838 | mutex_lock(&trace_types_lock); |
a695cb58 SRRH |
2839 | |
2840 | WARN_ON(!tr->ref); | |
2841 | tr->ref--; | |
2842 | ||
3928a8a2 SR |
2843 | for_each_tracing_cpu(cpu) { |
2844 | if (iter->buffer_iter[cpu]) | |
2845 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2846 | } | |
2847 | ||
bc0c38d1 SR |
2848 | if (iter->trace && iter->trace->close) |
2849 | iter->trace->close(iter); | |
2850 | ||
debdd57f HT |
2851 | if (!iter->snapshot) |
2852 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 2853 | tracing_start_tr(tr); |
bc0c38d1 SR |
2854 | mutex_unlock(&trace_types_lock); |
2855 | ||
d7350c3f | 2856 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2857 | free_cpumask_var(iter->started); |
d7350c3f | 2858 | kfree(iter->trace); |
6d158a81 | 2859 | kfree(iter->buffer_iter); |
50e18b94 | 2860 | seq_release_private(inode, file); |
bc0c38d1 SR |
2861 | return 0; |
2862 | } | |
2863 | ||
2864 | static int tracing_open(struct inode *inode, struct file *file) | |
2865 | { | |
85a2f9b4 SR |
2866 | struct trace_iterator *iter; |
2867 | int ret = 0; | |
bc0c38d1 | 2868 | |
4acd4d00 SR |
2869 | /* If this file was open for write, then erase contents */ |
2870 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2871 | (file->f_flags & O_TRUNC)) { |
2b6080f2 SR |
2872 | struct trace_cpu *tc = inode->i_private; |
2873 | struct trace_array *tr = tc->tr; | |
bc0c38d1 | 2874 | |
2b6080f2 | 2875 | if (tc->cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 2876 | tracing_reset_online_cpus(&tr->trace_buffer); |
4acd4d00 | 2877 | else |
12883efb | 2878 | tracing_reset(&tr->trace_buffer, tc->cpu); |
4acd4d00 | 2879 | } |
bc0c38d1 | 2880 | |
4acd4d00 | 2881 | if (file->f_mode & FMODE_READ) { |
debdd57f | 2882 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
2883 | if (IS_ERR(iter)) |
2884 | ret = PTR_ERR(iter); | |
2885 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2886 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2887 | } | |
bc0c38d1 SR |
2888 | return ret; |
2889 | } | |
2890 | ||
e309b41d | 2891 | static void * |
bc0c38d1 SR |
2892 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2893 | { | |
f129e965 | 2894 | struct tracer *t = v; |
bc0c38d1 SR |
2895 | |
2896 | (*pos)++; | |
2897 | ||
2898 | if (t) | |
2899 | t = t->next; | |
2900 | ||
bc0c38d1 SR |
2901 | return t; |
2902 | } | |
2903 | ||
2904 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2905 | { | |
f129e965 | 2906 | struct tracer *t; |
bc0c38d1 SR |
2907 | loff_t l = 0; |
2908 | ||
2909 | mutex_lock(&trace_types_lock); | |
f129e965 | 2910 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2911 | ; |
2912 | ||
2913 | return t; | |
2914 | } | |
2915 | ||
2916 | static void t_stop(struct seq_file *m, void *p) | |
2917 | { | |
2918 | mutex_unlock(&trace_types_lock); | |
2919 | } | |
2920 | ||
2921 | static int t_show(struct seq_file *m, void *v) | |
2922 | { | |
2923 | struct tracer *t = v; | |
2924 | ||
2925 | if (!t) | |
2926 | return 0; | |
2927 | ||
2928 | seq_printf(m, "%s", t->name); | |
2929 | if (t->next) | |
2930 | seq_putc(m, ' '); | |
2931 | else | |
2932 | seq_putc(m, '\n'); | |
2933 | ||
2934 | return 0; | |
2935 | } | |
2936 | ||
88e9d34c | 2937 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
2938 | .start = t_start, |
2939 | .next = t_next, | |
2940 | .stop = t_stop, | |
2941 | .show = t_show, | |
bc0c38d1 SR |
2942 | }; |
2943 | ||
2944 | static int show_traces_open(struct inode *inode, struct file *file) | |
2945 | { | |
60a11774 SR |
2946 | if (tracing_disabled) |
2947 | return -ENODEV; | |
2948 | ||
f129e965 | 2949 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2950 | } |
2951 | ||
4acd4d00 SR |
2952 | static ssize_t |
2953 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2954 | size_t count, loff_t *ppos) | |
2955 | { | |
2956 | return count; | |
2957 | } | |
2958 | ||
364829b1 SP |
2959 | static loff_t tracing_seek(struct file *file, loff_t offset, int origin) |
2960 | { | |
2961 | if (file->f_mode & FMODE_READ) | |
2962 | return seq_lseek(file, offset, origin); | |
2963 | else | |
2964 | return 0; | |
2965 | } | |
2966 | ||
5e2336a0 | 2967 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2968 | .open = tracing_open, |
2969 | .read = seq_read, | |
4acd4d00 | 2970 | .write = tracing_write_stub, |
364829b1 | 2971 | .llseek = tracing_seek, |
4bf39a94 | 2972 | .release = tracing_release, |
bc0c38d1 SR |
2973 | }; |
2974 | ||
5e2336a0 | 2975 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2976 | .open = show_traces_open, |
2977 | .read = seq_read, | |
2978 | .release = seq_release, | |
b444786f | 2979 | .llseek = seq_lseek, |
c7078de1 IM |
2980 | }; |
2981 | ||
36dfe925 IM |
2982 | /* |
2983 | * Only trace on a CPU if the bitmask is set: | |
2984 | */ | |
9e01c1b7 | 2985 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2986 | |
2987 | /* | |
2988 | * The tracer itself will not take this lock, but still we want | |
2989 | * to provide a consistent cpumask to user-space: | |
2990 | */ | |
2991 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2992 | ||
2993 | /* | |
2994 | * Temporary storage for the character representation of the | |
2995 | * CPU bitmask (and one more byte for the newline): | |
2996 | */ | |
2997 | static char mask_str[NR_CPUS + 1]; | |
2998 | ||
c7078de1 IM |
2999 | static ssize_t |
3000 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
3001 | size_t count, loff_t *ppos) | |
3002 | { | |
36dfe925 | 3003 | int len; |
c7078de1 IM |
3004 | |
3005 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 3006 | |
9e01c1b7 | 3007 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
3008 | if (count - len < 2) { |
3009 | count = -EINVAL; | |
3010 | goto out_err; | |
3011 | } | |
3012 | len += sprintf(mask_str + len, "\n"); | |
3013 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
3014 | ||
3015 | out_err: | |
c7078de1 IM |
3016 | mutex_unlock(&tracing_cpumask_update_lock); |
3017 | ||
3018 | return count; | |
3019 | } | |
3020 | ||
3021 | static ssize_t | |
3022 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
3023 | size_t count, loff_t *ppos) | |
3024 | { | |
2b6080f2 | 3025 | struct trace_array *tr = filp->private_data; |
9e01c1b7 | 3026 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 3027 | int err, cpu; |
9e01c1b7 RR |
3028 | |
3029 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
3030 | return -ENOMEM; | |
c7078de1 | 3031 | |
9e01c1b7 | 3032 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 3033 | if (err) |
36dfe925 IM |
3034 | goto err_unlock; |
3035 | ||
215368e8 LZ |
3036 | mutex_lock(&tracing_cpumask_update_lock); |
3037 | ||
a5e25883 | 3038 | local_irq_disable(); |
0199c4e6 | 3039 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 3040 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
3041 | /* |
3042 | * Increase/decrease the disabled counter if we are | |
3043 | * about to flip a bit in the cpumask: | |
3044 | */ | |
9e01c1b7 RR |
3045 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
3046 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
12883efb SRRH |
3047 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3048 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 3049 | } |
9e01c1b7 RR |
3050 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
3051 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
12883efb SRRH |
3052 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3053 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
3054 | } |
3055 | } | |
0199c4e6 | 3056 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 3057 | local_irq_enable(); |
36dfe925 | 3058 | |
9e01c1b7 | 3059 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
3060 | |
3061 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 3062 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
3063 | |
3064 | return count; | |
36dfe925 IM |
3065 | |
3066 | err_unlock: | |
215368e8 | 3067 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
3068 | |
3069 | return err; | |
c7078de1 IM |
3070 | } |
3071 | ||
5e2336a0 | 3072 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
3073 | .open = tracing_open_generic, |
3074 | .read = tracing_cpumask_read, | |
3075 | .write = tracing_cpumask_write, | |
b444786f | 3076 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3077 | }; |
3078 | ||
fdb372ed | 3079 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 3080 | { |
d8e83d26 | 3081 | struct tracer_opt *trace_opts; |
2b6080f2 | 3082 | struct trace_array *tr = m->private; |
d8e83d26 | 3083 | u32 tracer_flags; |
d8e83d26 | 3084 | int i; |
adf9f195 | 3085 | |
d8e83d26 | 3086 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3087 | tracer_flags = tr->current_trace->flags->val; |
3088 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 3089 | |
bc0c38d1 SR |
3090 | for (i = 0; trace_options[i]; i++) { |
3091 | if (trace_flags & (1 << i)) | |
fdb372ed | 3092 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 3093 | else |
fdb372ed | 3094 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
3095 | } |
3096 | ||
adf9f195 FW |
3097 | for (i = 0; trace_opts[i].name; i++) { |
3098 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 3099 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 3100 | else |
fdb372ed | 3101 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 3102 | } |
d8e83d26 | 3103 | mutex_unlock(&trace_types_lock); |
adf9f195 | 3104 | |
fdb372ed | 3105 | return 0; |
bc0c38d1 | 3106 | } |
bc0c38d1 | 3107 | |
8d18eaaf LZ |
3108 | static int __set_tracer_option(struct tracer *trace, |
3109 | struct tracer_flags *tracer_flags, | |
3110 | struct tracer_opt *opts, int neg) | |
3111 | { | |
3112 | int ret; | |
bc0c38d1 | 3113 | |
8d18eaaf LZ |
3114 | ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); |
3115 | if (ret) | |
3116 | return ret; | |
3117 | ||
3118 | if (neg) | |
3119 | tracer_flags->val &= ~opts->bit; | |
3120 | else | |
3121 | tracer_flags->val |= opts->bit; | |
3122 | return 0; | |
bc0c38d1 SR |
3123 | } |
3124 | ||
adf9f195 FW |
3125 | /* Try to assign a tracer specific option */ |
3126 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
3127 | { | |
7770841e | 3128 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 3129 | struct tracer_opt *opts = NULL; |
8d18eaaf | 3130 | int i; |
adf9f195 | 3131 | |
7770841e Z |
3132 | for (i = 0; tracer_flags->opts[i].name; i++) { |
3133 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 3134 | |
8d18eaaf LZ |
3135 | if (strcmp(cmp, opts->name) == 0) |
3136 | return __set_tracer_option(trace, trace->flags, | |
3137 | opts, neg); | |
adf9f195 | 3138 | } |
adf9f195 | 3139 | |
8d18eaaf | 3140 | return -EINVAL; |
adf9f195 FW |
3141 | } |
3142 | ||
613f04a0 SRRH |
3143 | /* Some tracers require overwrite to stay enabled */ |
3144 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
3145 | { | |
3146 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
3147 | return -1; | |
3148 | ||
3149 | return 0; | |
3150 | } | |
3151 | ||
2b6080f2 | 3152 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
3153 | { |
3154 | /* do nothing if flag is already set */ | |
3155 | if (!!(trace_flags & mask) == !!enabled) | |
613f04a0 SRRH |
3156 | return 0; |
3157 | ||
3158 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 SR |
3159 | if (tr->current_trace->flag_changed) |
3160 | if (tr->current_trace->flag_changed(tr->current_trace, mask, !!enabled)) | |
613f04a0 | 3161 | return -EINVAL; |
af4617bd SR |
3162 | |
3163 | if (enabled) | |
3164 | trace_flags |= mask; | |
3165 | else | |
3166 | trace_flags &= ~mask; | |
e870e9a1 LZ |
3167 | |
3168 | if (mask == TRACE_ITER_RECORD_CMD) | |
3169 | trace_event_enable_cmd_record(enabled); | |
750912fa | 3170 | |
80902822 | 3171 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 3172 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 3173 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 3174 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
3175 | #endif |
3176 | } | |
81698831 SR |
3177 | |
3178 | if (mask == TRACE_ITER_PRINTK) | |
3179 | trace_printk_start_stop_comm(enabled); | |
613f04a0 SRRH |
3180 | |
3181 | return 0; | |
af4617bd SR |
3182 | } |
3183 | ||
2b6080f2 | 3184 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 3185 | { |
8d18eaaf | 3186 | char *cmp; |
bc0c38d1 | 3187 | int neg = 0; |
613f04a0 | 3188 | int ret = -ENODEV; |
bc0c38d1 SR |
3189 | int i; |
3190 | ||
7bcfaf54 | 3191 | cmp = strstrip(option); |
bc0c38d1 | 3192 | |
8d18eaaf | 3193 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3194 | neg = 1; |
3195 | cmp += 2; | |
3196 | } | |
3197 | ||
69d34da2 SRRH |
3198 | mutex_lock(&trace_types_lock); |
3199 | ||
bc0c38d1 | 3200 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3201 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3202 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3203 | break; |
3204 | } | |
3205 | } | |
adf9f195 FW |
3206 | |
3207 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3208 | if (!trace_options[i]) |
2b6080f2 | 3209 | ret = set_tracer_option(tr->current_trace, cmp, neg); |
69d34da2 SRRH |
3210 | |
3211 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3212 | |
7bcfaf54 SR |
3213 | return ret; |
3214 | } | |
3215 | ||
3216 | static ssize_t | |
3217 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3218 | size_t cnt, loff_t *ppos) | |
3219 | { | |
2b6080f2 SR |
3220 | struct seq_file *m = filp->private_data; |
3221 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3222 | char buf[64]; |
613f04a0 | 3223 | int ret; |
7bcfaf54 SR |
3224 | |
3225 | if (cnt >= sizeof(buf)) | |
3226 | return -EINVAL; | |
3227 | ||
3228 | if (copy_from_user(&buf, ubuf, cnt)) | |
3229 | return -EFAULT; | |
3230 | ||
a8dd2176 SR |
3231 | buf[cnt] = 0; |
3232 | ||
2b6080f2 | 3233 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
3234 | if (ret < 0) |
3235 | return ret; | |
7bcfaf54 | 3236 | |
cf8517cf | 3237 | *ppos += cnt; |
bc0c38d1 SR |
3238 | |
3239 | return cnt; | |
3240 | } | |
3241 | ||
fdb372ed LZ |
3242 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
3243 | { | |
3244 | if (tracing_disabled) | |
3245 | return -ENODEV; | |
2b6080f2 SR |
3246 | |
3247 | return single_open(file, tracing_trace_options_show, inode->i_private); | |
fdb372ed LZ |
3248 | } |
3249 | ||
5e2336a0 | 3250 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
3251 | .open = tracing_trace_options_open, |
3252 | .read = seq_read, | |
3253 | .llseek = seq_lseek, | |
3254 | .release = single_release, | |
ee6bce52 | 3255 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
3256 | }; |
3257 | ||
7bd2f24c IM |
3258 | static const char readme_msg[] = |
3259 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
3260 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
3261 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
1e42e83f | 3262 | "wakeup wakeup_rt preemptirqsoff preemptoff irqsoff function nop\n\n" |
156f5a78 | 3263 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 3264 | "nop\n" |
1e42e83f | 3265 | "# echo wakeup > /sys/kernel/debug/tracing/current_tracer\n" |
156f5a78 | 3266 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
1e42e83f | 3267 | "wakeup\n" |
156f5a78 | 3268 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 3269 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 | 3270 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
9b5f8b31 | 3271 | "# echo 1 > /sys/kernel/debug/tracing/tracing_on\n" |
156f5a78 | 3272 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" |
9b5f8b31 | 3273 | "# echo 0 > /sys/kernel/debug/tracing/tracing_on\n" |
7bd2f24c IM |
3274 | ; |
3275 | ||
3276 | static ssize_t | |
3277 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
3278 | size_t cnt, loff_t *ppos) | |
3279 | { | |
3280 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
3281 | readme_msg, strlen(readme_msg)); | |
3282 | } | |
3283 | ||
5e2336a0 | 3284 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
3285 | .open = tracing_open_generic, |
3286 | .read = tracing_readme_read, | |
b444786f | 3287 | .llseek = generic_file_llseek, |
7bd2f24c IM |
3288 | }; |
3289 | ||
69abe6a5 AP |
3290 | static ssize_t |
3291 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
3292 | size_t cnt, loff_t *ppos) | |
3293 | { | |
3294 | char *buf_comm; | |
3295 | char *file_buf; | |
3296 | char *buf; | |
3297 | int len = 0; | |
3298 | int pid; | |
3299 | int i; | |
3300 | ||
3301 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
3302 | if (!file_buf) | |
3303 | return -ENOMEM; | |
3304 | ||
3305 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
3306 | if (!buf_comm) { | |
3307 | kfree(file_buf); | |
3308 | return -ENOMEM; | |
3309 | } | |
3310 | ||
3311 | buf = file_buf; | |
3312 | ||
3313 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
3314 | int r; | |
3315 | ||
3316 | pid = map_cmdline_to_pid[i]; | |
3317 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
3318 | continue; | |
3319 | ||
3320 | trace_find_cmdline(pid, buf_comm); | |
3321 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
3322 | buf += r; | |
3323 | len += r; | |
3324 | } | |
3325 | ||
3326 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
3327 | file_buf, len); | |
3328 | ||
3329 | kfree(file_buf); | |
3330 | kfree(buf_comm); | |
3331 | ||
3332 | return len; | |
3333 | } | |
3334 | ||
3335 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
3336 | .open = tracing_open_generic, | |
3337 | .read = tracing_saved_cmdlines_read, | |
b444786f | 3338 | .llseek = generic_file_llseek, |
69abe6a5 AP |
3339 | }; |
3340 | ||
bc0c38d1 SR |
3341 | static ssize_t |
3342 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
3343 | size_t cnt, loff_t *ppos) | |
3344 | { | |
2b6080f2 | 3345 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 3346 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
3347 | int r; |
3348 | ||
3349 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 3350 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
3351 | mutex_unlock(&trace_types_lock); |
3352 | ||
4bf39a94 | 3353 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3354 | } |
3355 | ||
b6f11df2 ACM |
3356 | int tracer_init(struct tracer *t, struct trace_array *tr) |
3357 | { | |
12883efb | 3358 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
3359 | return t->init(tr); |
3360 | } | |
3361 | ||
12883efb | 3362 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
3363 | { |
3364 | int cpu; | |
737223fb | 3365 | |
438ced17 | 3366 | for_each_tracing_cpu(cpu) |
12883efb | 3367 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
3368 | } |
3369 | ||
12883efb | 3370 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 3371 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
3372 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
3373 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
3374 | { |
3375 | int cpu, ret = 0; | |
3376 | ||
3377 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
3378 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
3379 | ret = ring_buffer_resize(trace_buf->buffer, |
3380 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
3381 | if (ret < 0) |
3382 | break; | |
12883efb SRRH |
3383 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
3384 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
3385 | } |
3386 | } else { | |
12883efb SRRH |
3387 | ret = ring_buffer_resize(trace_buf->buffer, |
3388 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 3389 | if (ret == 0) |
12883efb SRRH |
3390 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
3391 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
3392 | } |
3393 | ||
3394 | return ret; | |
3395 | } | |
12883efb | 3396 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 3397 | |
2b6080f2 SR |
3398 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
3399 | unsigned long size, int cpu) | |
73c5162a SR |
3400 | { |
3401 | int ret; | |
3402 | ||
3403 | /* | |
3404 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3405 | * we use the size that was given, and we can forget about |
3406 | * expanding it later. | |
73c5162a | 3407 | */ |
55034cd6 | 3408 | ring_buffer_expanded = true; |
73c5162a | 3409 | |
b382ede6 | 3410 | /* May be called before buffers are initialized */ |
12883efb | 3411 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
3412 | return 0; |
3413 | ||
12883efb | 3414 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
3415 | if (ret < 0) |
3416 | return ret; | |
3417 | ||
12883efb | 3418 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
3419 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
3420 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
3421 | goto out; |
3422 | ||
12883efb | 3423 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 3424 | if (ret < 0) { |
12883efb SRRH |
3425 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
3426 | &tr->trace_buffer, cpu); | |
73c5162a | 3427 | if (r < 0) { |
a123c52b SR |
3428 | /* |
3429 | * AARGH! We are left with different | |
3430 | * size max buffer!!!! | |
3431 | * The max buffer is our "snapshot" buffer. | |
3432 | * When a tracer needs a snapshot (one of the | |
3433 | * latency tracers), it swaps the max buffer | |
3434 | * with the saved snap shot. We succeeded to | |
3435 | * update the size of the main buffer, but failed to | |
3436 | * update the size of the max buffer. But when we tried | |
3437 | * to reset the main buffer to the original size, we | |
3438 | * failed there too. This is very unlikely to | |
3439 | * happen, but if it does, warn and kill all | |
3440 | * tracing. | |
3441 | */ | |
73c5162a SR |
3442 | WARN_ON(1); |
3443 | tracing_disabled = 1; | |
3444 | } | |
3445 | return ret; | |
3446 | } | |
3447 | ||
438ced17 | 3448 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3449 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 3450 | else |
12883efb | 3451 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 3452 | |
ef710e10 | 3453 | out: |
12883efb SRRH |
3454 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
3455 | ||
438ced17 | 3456 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3457 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 3458 | else |
12883efb | 3459 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
3460 | |
3461 | return ret; | |
3462 | } | |
3463 | ||
2b6080f2 SR |
3464 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
3465 | unsigned long size, int cpu_id) | |
4f271a2a | 3466 | { |
83f40318 | 3467 | int ret = size; |
4f271a2a VN |
3468 | |
3469 | mutex_lock(&trace_types_lock); | |
3470 | ||
438ced17 VN |
3471 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
3472 | /* make sure, this cpu is enabled in the mask */ | |
3473 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
3474 | ret = -EINVAL; | |
3475 | goto out; | |
3476 | } | |
3477 | } | |
4f271a2a | 3478 | |
2b6080f2 | 3479 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
3480 | if (ret < 0) |
3481 | ret = -ENOMEM; | |
3482 | ||
438ced17 | 3483 | out: |
4f271a2a VN |
3484 | mutex_unlock(&trace_types_lock); |
3485 | ||
3486 | return ret; | |
3487 | } | |
3488 | ||
ef710e10 | 3489 | |
1852fcce SR |
3490 | /** |
3491 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
3492 | * | |
3493 | * To save on memory when the tracing is never used on a system with it | |
3494 | * configured in. The ring buffers are set to a minimum size. But once | |
3495 | * a user starts to use the tracing facility, then they need to grow | |
3496 | * to their default size. | |
3497 | * | |
3498 | * This function is to be called when a tracer is about to be used. | |
3499 | */ | |
3500 | int tracing_update_buffers(void) | |
3501 | { | |
3502 | int ret = 0; | |
3503 | ||
1027fcb2 | 3504 | mutex_lock(&trace_types_lock); |
1852fcce | 3505 | if (!ring_buffer_expanded) |
2b6080f2 | 3506 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 3507 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 3508 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
3509 | |
3510 | return ret; | |
3511 | } | |
3512 | ||
577b785f SR |
3513 | struct trace_option_dentry; |
3514 | ||
3515 | static struct trace_option_dentry * | |
2b6080f2 | 3516 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f SR |
3517 | |
3518 | static void | |
3519 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
3520 | ||
b2821ae6 | 3521 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 3522 | { |
577b785f | 3523 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
3524 | struct trace_array *tr = &global_trace; |
3525 | struct tracer *t; | |
12883efb | 3526 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 3527 | bool had_max_tr; |
12883efb | 3528 | #endif |
d9e54076 | 3529 | int ret = 0; |
bc0c38d1 | 3530 | |
1027fcb2 SR |
3531 | mutex_lock(&trace_types_lock); |
3532 | ||
73c5162a | 3533 | if (!ring_buffer_expanded) { |
2b6080f2 | 3534 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 3535 | RING_BUFFER_ALL_CPUS); |
73c5162a | 3536 | if (ret < 0) |
59f586db | 3537 | goto out; |
73c5162a SR |
3538 | ret = 0; |
3539 | } | |
3540 | ||
bc0c38d1 SR |
3541 | for (t = trace_types; t; t = t->next) { |
3542 | if (strcmp(t->name, buf) == 0) | |
3543 | break; | |
3544 | } | |
c2931e05 FW |
3545 | if (!t) { |
3546 | ret = -EINVAL; | |
3547 | goto out; | |
3548 | } | |
2b6080f2 | 3549 | if (t == tr->current_trace) |
bc0c38d1 SR |
3550 | goto out; |
3551 | ||
9f029e83 | 3552 | trace_branch_disable(); |
613f04a0 | 3553 | |
2b6080f2 | 3554 | tr->current_trace->enabled = false; |
613f04a0 | 3555 | |
2b6080f2 SR |
3556 | if (tr->current_trace->reset) |
3557 | tr->current_trace->reset(tr); | |
34600f0e | 3558 | |
12883efb | 3559 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 3560 | tr->current_trace = &nop_trace; |
34600f0e | 3561 | |
45ad21ca SRRH |
3562 | #ifdef CONFIG_TRACER_MAX_TRACE |
3563 | had_max_tr = tr->allocated_snapshot; | |
3564 | ||
34600f0e SR |
3565 | if (had_max_tr && !t->use_max_tr) { |
3566 | /* | |
3567 | * We need to make sure that the update_max_tr sees that | |
3568 | * current_trace changed to nop_trace to keep it from | |
3569 | * swapping the buffers after we resize it. | |
3570 | * The update_max_tr is called from interrupts disabled | |
3571 | * so a synchronized_sched() is sufficient. | |
3572 | */ | |
3573 | synchronize_sched(); | |
ef710e10 KM |
3574 | /* |
3575 | * We don't free the ring buffer. instead, resize it because | |
3576 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
3577 | * we want preserve it. | |
3578 | */ | |
12883efb SRRH |
3579 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); |
3580 | set_buffer_entries(&tr->max_buffer, 1); | |
3581 | tracing_reset_online_cpus(&tr->max_buffer); | |
45ad21ca | 3582 | tr->allocated_snapshot = false; |
ef710e10 | 3583 | } |
12883efb | 3584 | #endif |
577b785f SR |
3585 | destroy_trace_option_files(topts); |
3586 | ||
2b6080f2 | 3587 | topts = create_trace_option_files(tr, t); |
12883efb SRRH |
3588 | |
3589 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 3590 | if (t->use_max_tr && !had_max_tr) { |
438ced17 | 3591 | /* we need to make per cpu buffer sizes equivalent */ |
12883efb | 3592 | ret = resize_buffer_duplicate_size(&tr->max_buffer, &tr->trace_buffer, |
d60da506 HT |
3593 | RING_BUFFER_ALL_CPUS); |
3594 | if (ret < 0) | |
3595 | goto out; | |
45ad21ca | 3596 | tr->allocated_snapshot = true; |
ef710e10 | 3597 | } |
12883efb | 3598 | #endif |
577b785f | 3599 | |
1c80025a | 3600 | if (t->init) { |
b6f11df2 | 3601 | ret = tracer_init(t, tr); |
1c80025a FW |
3602 | if (ret) |
3603 | goto out; | |
3604 | } | |
bc0c38d1 | 3605 | |
2b6080f2 SR |
3606 | tr->current_trace = t; |
3607 | tr->current_trace->enabled = true; | |
9f029e83 | 3608 | trace_branch_enable(tr); |
bc0c38d1 SR |
3609 | out: |
3610 | mutex_unlock(&trace_types_lock); | |
3611 | ||
d9e54076 PZ |
3612 | return ret; |
3613 | } | |
3614 | ||
3615 | static ssize_t | |
3616 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
3617 | size_t cnt, loff_t *ppos) | |
3618 | { | |
ee6c2c1b | 3619 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
3620 | int i; |
3621 | size_t ret; | |
e6e7a65a FW |
3622 | int err; |
3623 | ||
3624 | ret = cnt; | |
d9e54076 | 3625 | |
ee6c2c1b LZ |
3626 | if (cnt > MAX_TRACER_SIZE) |
3627 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
3628 | |
3629 | if (copy_from_user(&buf, ubuf, cnt)) | |
3630 | return -EFAULT; | |
3631 | ||
3632 | buf[cnt] = 0; | |
3633 | ||
3634 | /* strip ending whitespace. */ | |
3635 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
3636 | buf[i] = 0; | |
3637 | ||
e6e7a65a FW |
3638 | err = tracing_set_tracer(buf); |
3639 | if (err) | |
3640 | return err; | |
d9e54076 | 3641 | |
cf8517cf | 3642 | *ppos += ret; |
bc0c38d1 | 3643 | |
c2931e05 | 3644 | return ret; |
bc0c38d1 SR |
3645 | } |
3646 | ||
3647 | static ssize_t | |
3648 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
3649 | size_t cnt, loff_t *ppos) | |
3650 | { | |
3651 | unsigned long *ptr = filp->private_data; | |
3652 | char buf[64]; | |
3653 | int r; | |
3654 | ||
cffae437 | 3655 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 3656 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
3657 | if (r > sizeof(buf)) |
3658 | r = sizeof(buf); | |
4bf39a94 | 3659 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3660 | } |
3661 | ||
3662 | static ssize_t | |
3663 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
3664 | size_t cnt, loff_t *ppos) | |
3665 | { | |
5e39841c | 3666 | unsigned long *ptr = filp->private_data; |
5e39841c | 3667 | unsigned long val; |
c6caeeb1 | 3668 | int ret; |
bc0c38d1 | 3669 | |
22fe9b54 PH |
3670 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3671 | if (ret) | |
c6caeeb1 | 3672 | return ret; |
bc0c38d1 SR |
3673 | |
3674 | *ptr = val * 1000; | |
3675 | ||
3676 | return cnt; | |
3677 | } | |
3678 | ||
b3806b43 SR |
3679 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
3680 | { | |
2b6080f2 SR |
3681 | struct trace_cpu *tc = inode->i_private; |
3682 | struct trace_array *tr = tc->tr; | |
b3806b43 | 3683 | struct trace_iterator *iter; |
b04cc6b1 | 3684 | int ret = 0; |
b3806b43 SR |
3685 | |
3686 | if (tracing_disabled) | |
3687 | return -ENODEV; | |
3688 | ||
b04cc6b1 FW |
3689 | mutex_lock(&trace_types_lock); |
3690 | ||
b3806b43 SR |
3691 | /* create a buffer to store the information to pass to userspace */ |
3692 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
3693 | if (!iter) { |
3694 | ret = -ENOMEM; | |
3695 | goto out; | |
3696 | } | |
b3806b43 | 3697 | |
d7350c3f FW |
3698 | /* |
3699 | * We make a copy of the current tracer to avoid concurrent | |
3700 | * changes on it while we are reading. | |
3701 | */ | |
3702 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
3703 | if (!iter->trace) { | |
3704 | ret = -ENOMEM; | |
3705 | goto fail; | |
3706 | } | |
2b6080f2 | 3707 | *iter->trace = *tr->current_trace; |
d7350c3f | 3708 | |
4462344e | 3709 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 3710 | ret = -ENOMEM; |
d7350c3f | 3711 | goto fail; |
4462344e RR |
3712 | } |
3713 | ||
a309720c | 3714 | /* trace pipe does not show start of buffer */ |
4462344e | 3715 | cpumask_setall(iter->started); |
a309720c | 3716 | |
112f38a7 SR |
3717 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
3718 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3719 | ||
8be0709f DS |
3720 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
3721 | if (trace_clocks[trace_clock_id].in_ns) | |
3722 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
3723 | ||
2b6080f2 SR |
3724 | iter->cpu_file = tc->cpu; |
3725 | iter->tr = tc->tr; | |
12883efb | 3726 | iter->trace_buffer = &tc->tr->trace_buffer; |
d7350c3f | 3727 | mutex_init(&iter->mutex); |
b3806b43 SR |
3728 | filp->private_data = iter; |
3729 | ||
107bad8b SR |
3730 | if (iter->trace->pipe_open) |
3731 | iter->trace->pipe_open(iter); | |
107bad8b | 3732 | |
b444786f | 3733 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
3734 | out: |
3735 | mutex_unlock(&trace_types_lock); | |
3736 | return ret; | |
d7350c3f FW |
3737 | |
3738 | fail: | |
3739 | kfree(iter->trace); | |
3740 | kfree(iter); | |
3741 | mutex_unlock(&trace_types_lock); | |
3742 | return ret; | |
b3806b43 SR |
3743 | } |
3744 | ||
3745 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
3746 | { | |
3747 | struct trace_iterator *iter = file->private_data; | |
3748 | ||
b04cc6b1 FW |
3749 | mutex_lock(&trace_types_lock); |
3750 | ||
29bf4a5e | 3751 | if (iter->trace->pipe_close) |
c521efd1 SR |
3752 | iter->trace->pipe_close(iter); |
3753 | ||
b04cc6b1 FW |
3754 | mutex_unlock(&trace_types_lock); |
3755 | ||
4462344e | 3756 | free_cpumask_var(iter->started); |
d7350c3f FW |
3757 | mutex_destroy(&iter->mutex); |
3758 | kfree(iter->trace); | |
b3806b43 | 3759 | kfree(iter); |
b3806b43 SR |
3760 | |
3761 | return 0; | |
3762 | } | |
3763 | ||
2a2cc8f7 | 3764 | static unsigned int |
cc60cdc9 | 3765 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 3766 | { |
15693458 SRRH |
3767 | /* Iterators are static, they should be filled or empty */ |
3768 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
3769 | return POLLIN | POLLRDNORM; | |
3770 | ||
3771 | if (trace_flags & TRACE_ITER_BLOCK) | |
2a2cc8f7 SSP |
3772 | /* |
3773 | * Always select as readable when in blocking mode | |
3774 | */ | |
3775 | return POLLIN | POLLRDNORM; | |
15693458 | 3776 | else |
12883efb | 3777 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 3778 | filp, poll_table); |
2a2cc8f7 SSP |
3779 | } |
3780 | ||
cc60cdc9 SR |
3781 | static unsigned int |
3782 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
3783 | { | |
3784 | struct trace_iterator *iter = filp->private_data; | |
3785 | ||
3786 | return trace_poll(iter, filp, poll_table); | |
3787 | } | |
3788 | ||
6eaaa5d5 FW |
3789 | /* |
3790 | * This is a make-shift waitqueue. | |
3791 | * A tracer might use this callback on some rare cases: | |
3792 | * | |
3793 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
3794 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
3795 | * 2) the function tracers, trace all functions, we don't want | |
3796 | * the overhead of calling wake_up and friends | |
3797 | * (and tracing them too) | |
3798 | * | |
3799 | * Anyway, this is really very primitive wakeup. | |
3800 | */ | |
3801 | void poll_wait_pipe(struct trace_iterator *iter) | |
3802 | { | |
3803 | set_current_state(TASK_INTERRUPTIBLE); | |
3804 | /* sleep for 100 msecs, and try again. */ | |
3805 | schedule_timeout(HZ / 10); | |
3806 | } | |
3807 | ||
ff98781b EGM |
3808 | /* Must be called with trace_types_lock mutex held. */ |
3809 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
3810 | { |
3811 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 3812 | |
b3806b43 | 3813 | while (trace_empty(iter)) { |
2dc8f095 | 3814 | |
107bad8b | 3815 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 3816 | return -EAGAIN; |
107bad8b | 3817 | } |
2dc8f095 | 3818 | |
d7350c3f | 3819 | mutex_unlock(&iter->mutex); |
107bad8b | 3820 | |
6eaaa5d5 | 3821 | iter->trace->wait_pipe(iter); |
b3806b43 | 3822 | |
d7350c3f | 3823 | mutex_lock(&iter->mutex); |
107bad8b | 3824 | |
6eaaa5d5 | 3825 | if (signal_pending(current)) |
ff98781b | 3826 | return -EINTR; |
b3806b43 SR |
3827 | |
3828 | /* | |
250bfd3d | 3829 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
3830 | * We still block if tracing is disabled, but we have never |
3831 | * read anything. This allows a user to cat this file, and | |
3832 | * then enable tracing. But after we have read something, | |
3833 | * we give an EOF when tracing is again disabled. | |
3834 | * | |
3835 | * iter->pos will be 0 if we haven't read anything. | |
3836 | */ | |
250bfd3d | 3837 | if (!tracing_is_enabled() && iter->pos) |
b3806b43 | 3838 | break; |
b3806b43 SR |
3839 | } |
3840 | ||
ff98781b EGM |
3841 | return 1; |
3842 | } | |
3843 | ||
3844 | /* | |
3845 | * Consumer reader. | |
3846 | */ | |
3847 | static ssize_t | |
3848 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
3849 | size_t cnt, loff_t *ppos) | |
3850 | { | |
3851 | struct trace_iterator *iter = filp->private_data; | |
2b6080f2 | 3852 | struct trace_array *tr = iter->tr; |
ff98781b EGM |
3853 | ssize_t sret; |
3854 | ||
3855 | /* return any leftover data */ | |
3856 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
3857 | if (sret != -EBUSY) | |
3858 | return sret; | |
3859 | ||
f9520750 | 3860 | trace_seq_init(&iter->seq); |
ff98781b | 3861 | |
d7350c3f | 3862 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 3863 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3864 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
3865 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
3866 | mutex_unlock(&trace_types_lock); |
3867 | ||
3868 | /* | |
3869 | * Avoid more than one consumer on a single file descriptor | |
3870 | * This is just a matter of traces coherency, the ring buffer itself | |
3871 | * is protected. | |
3872 | */ | |
3873 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
3874 | if (iter->trace->read) { |
3875 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
3876 | if (sret) | |
3877 | goto out; | |
3878 | } | |
3879 | ||
3880 | waitagain: | |
3881 | sret = tracing_wait_pipe(filp); | |
3882 | if (sret <= 0) | |
3883 | goto out; | |
3884 | ||
b3806b43 | 3885 | /* stop when tracing is finished */ |
ff98781b EGM |
3886 | if (trace_empty(iter)) { |
3887 | sret = 0; | |
107bad8b | 3888 | goto out; |
ff98781b | 3889 | } |
b3806b43 SR |
3890 | |
3891 | if (cnt >= PAGE_SIZE) | |
3892 | cnt = PAGE_SIZE - 1; | |
3893 | ||
53d0aa77 | 3894 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
3895 | memset(&iter->seq, 0, |
3896 | sizeof(struct trace_iterator) - | |
3897 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 3898 | iter->pos = -1; |
b3806b43 | 3899 | |
4f535968 | 3900 | trace_event_read_lock(); |
7e53bd42 | 3901 | trace_access_lock(iter->cpu_file); |
955b61e5 | 3902 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 3903 | enum print_line_t ret; |
088b1e42 SR |
3904 | int len = iter->seq.len; |
3905 | ||
f9896bf3 | 3906 | ret = print_trace_line(iter); |
2c4f035f | 3907 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
3908 | /* don't print partial lines */ |
3909 | iter->seq.len = len; | |
b3806b43 | 3910 | break; |
088b1e42 | 3911 | } |
b91facc3 FW |
3912 | if (ret != TRACE_TYPE_NO_CONSUME) |
3913 | trace_consume(iter); | |
b3806b43 SR |
3914 | |
3915 | if (iter->seq.len >= cnt) | |
3916 | break; | |
ee5e51f5 JO |
3917 | |
3918 | /* | |
3919 | * Setting the full flag means we reached the trace_seq buffer | |
3920 | * size and we should leave by partial output condition above. | |
3921 | * One of the trace_seq_* functions is not used properly. | |
3922 | */ | |
3923 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
3924 | iter->ent->type); | |
b3806b43 | 3925 | } |
7e53bd42 | 3926 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3927 | trace_event_read_unlock(); |
b3806b43 | 3928 | |
b3806b43 | 3929 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3930 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3931 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3932 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3933 | |
3934 | /* | |
25985edc | 3935 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
3936 | * entries, go back to wait for more entries. |
3937 | */ | |
6c6c2796 | 3938 | if (sret == -EBUSY) |
9ff4b974 | 3939 | goto waitagain; |
b3806b43 | 3940 | |
107bad8b | 3941 | out: |
d7350c3f | 3942 | mutex_unlock(&iter->mutex); |
107bad8b | 3943 | |
6c6c2796 | 3944 | return sret; |
b3806b43 SR |
3945 | } |
3946 | ||
3c56819b EGM |
3947 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3948 | struct pipe_buffer *buf) | |
3949 | { | |
3950 | __free_page(buf->page); | |
3951 | } | |
3952 | ||
3953 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3954 | unsigned int idx) | |
3955 | { | |
3956 | __free_page(spd->pages[idx]); | |
3957 | } | |
3958 | ||
28dfef8f | 3959 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
3960 | .can_merge = 0, |
3961 | .map = generic_pipe_buf_map, | |
3962 | .unmap = generic_pipe_buf_unmap, | |
3963 | .confirm = generic_pipe_buf_confirm, | |
3964 | .release = tracing_pipe_buf_release, | |
3965 | .steal = generic_pipe_buf_steal, | |
3966 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3967 | }; |
3968 | ||
34cd4998 | 3969 | static size_t |
fa7c7f6e | 3970 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3971 | { |
3972 | size_t count; | |
3973 | int ret; | |
3974 | ||
3975 | /* Seq buffer is page-sized, exactly what we need. */ | |
3976 | for (;;) { | |
3977 | count = iter->seq.len; | |
3978 | ret = print_trace_line(iter); | |
3979 | count = iter->seq.len - count; | |
3980 | if (rem < count) { | |
3981 | rem = 0; | |
3982 | iter->seq.len -= count; | |
3983 | break; | |
3984 | } | |
3985 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3986 | iter->seq.len -= count; | |
3987 | break; | |
3988 | } | |
3989 | ||
74e7ff8c LJ |
3990 | if (ret != TRACE_TYPE_NO_CONSUME) |
3991 | trace_consume(iter); | |
34cd4998 | 3992 | rem -= count; |
955b61e5 | 3993 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
3994 | rem = 0; |
3995 | iter->ent = NULL; | |
3996 | break; | |
3997 | } | |
3998 | } | |
3999 | ||
4000 | return rem; | |
4001 | } | |
4002 | ||
3c56819b EGM |
4003 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
4004 | loff_t *ppos, | |
4005 | struct pipe_inode_info *pipe, | |
4006 | size_t len, | |
4007 | unsigned int flags) | |
4008 | { | |
35f3d14d JA |
4009 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
4010 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
4011 | struct trace_iterator *iter = filp->private_data; |
4012 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
4013 | .pages = pages_def, |
4014 | .partial = partial_def, | |
34cd4998 | 4015 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 4016 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
4017 | .flags = flags, |
4018 | .ops = &tracing_pipe_buf_ops, | |
4019 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 4020 | }; |
2b6080f2 | 4021 | struct trace_array *tr = iter->tr; |
3c56819b | 4022 | ssize_t ret; |
34cd4998 | 4023 | size_t rem; |
3c56819b EGM |
4024 | unsigned int i; |
4025 | ||
35f3d14d JA |
4026 | if (splice_grow_spd(pipe, &spd)) |
4027 | return -ENOMEM; | |
4028 | ||
d7350c3f | 4029 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 4030 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4031 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4032 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4033 | mutex_unlock(&trace_types_lock); |
4034 | ||
4035 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
4036 | |
4037 | if (iter->trace->splice_read) { | |
4038 | ret = iter->trace->splice_read(iter, filp, | |
4039 | ppos, pipe, len, flags); | |
4040 | if (ret) | |
34cd4998 | 4041 | goto out_err; |
3c56819b EGM |
4042 | } |
4043 | ||
4044 | ret = tracing_wait_pipe(filp); | |
4045 | if (ret <= 0) | |
34cd4998 | 4046 | goto out_err; |
3c56819b | 4047 | |
955b61e5 | 4048 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 4049 | ret = -EFAULT; |
34cd4998 | 4050 | goto out_err; |
3c56819b EGM |
4051 | } |
4052 | ||
4f535968 | 4053 | trace_event_read_lock(); |
7e53bd42 | 4054 | trace_access_lock(iter->cpu_file); |
4f535968 | 4055 | |
3c56819b | 4056 | /* Fill as many pages as possible. */ |
35f3d14d JA |
4057 | for (i = 0, rem = len; i < pipe->buffers && rem; i++) { |
4058 | spd.pages[i] = alloc_page(GFP_KERNEL); | |
4059 | if (!spd.pages[i]) | |
34cd4998 | 4060 | break; |
3c56819b | 4061 | |
fa7c7f6e | 4062 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
4063 | |
4064 | /* Copy the data into the page, so we can start over. */ | |
4065 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 4066 | page_address(spd.pages[i]), |
3c56819b EGM |
4067 | iter->seq.len); |
4068 | if (ret < 0) { | |
35f3d14d | 4069 | __free_page(spd.pages[i]); |
3c56819b EGM |
4070 | break; |
4071 | } | |
35f3d14d JA |
4072 | spd.partial[i].offset = 0; |
4073 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 4074 | |
f9520750 | 4075 | trace_seq_init(&iter->seq); |
3c56819b EGM |
4076 | } |
4077 | ||
7e53bd42 | 4078 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4079 | trace_event_read_unlock(); |
d7350c3f | 4080 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
4081 | |
4082 | spd.nr_pages = i; | |
4083 | ||
35f3d14d JA |
4084 | ret = splice_to_pipe(pipe, &spd); |
4085 | out: | |
047fe360 | 4086 | splice_shrink_spd(&spd); |
35f3d14d | 4087 | return ret; |
3c56819b | 4088 | |
34cd4998 | 4089 | out_err: |
d7350c3f | 4090 | mutex_unlock(&iter->mutex); |
35f3d14d | 4091 | goto out; |
3c56819b EGM |
4092 | } |
4093 | ||
a98a3c3f SR |
4094 | static ssize_t |
4095 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
4096 | size_t cnt, loff_t *ppos) | |
4097 | { | |
2b6080f2 SR |
4098 | struct trace_cpu *tc = filp->private_data; |
4099 | struct trace_array *tr = tc->tr; | |
438ced17 VN |
4100 | char buf[64]; |
4101 | int r = 0; | |
4102 | ssize_t ret; | |
a98a3c3f | 4103 | |
db526ca3 | 4104 | mutex_lock(&trace_types_lock); |
438ced17 | 4105 | |
2b6080f2 | 4106 | if (tc->cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
4107 | int cpu, buf_size_same; |
4108 | unsigned long size; | |
4109 | ||
4110 | size = 0; | |
4111 | buf_size_same = 1; | |
4112 | /* check if all cpu sizes are same */ | |
4113 | for_each_tracing_cpu(cpu) { | |
4114 | /* fill in the size from first enabled cpu */ | |
4115 | if (size == 0) | |
12883efb SRRH |
4116 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
4117 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
4118 | buf_size_same = 0; |
4119 | break; | |
4120 | } | |
4121 | } | |
4122 | ||
4123 | if (buf_size_same) { | |
4124 | if (!ring_buffer_expanded) | |
4125 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
4126 | size >> 10, | |
4127 | trace_buf_size >> 10); | |
4128 | else | |
4129 | r = sprintf(buf, "%lu\n", size >> 10); | |
4130 | } else | |
4131 | r = sprintf(buf, "X\n"); | |
4132 | } else | |
12883efb | 4133 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, tc->cpu)->entries >> 10); |
438ced17 | 4134 | |
db526ca3 SR |
4135 | mutex_unlock(&trace_types_lock); |
4136 | ||
438ced17 VN |
4137 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
4138 | return ret; | |
a98a3c3f SR |
4139 | } |
4140 | ||
4141 | static ssize_t | |
4142 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
4143 | size_t cnt, loff_t *ppos) | |
4144 | { | |
2b6080f2 | 4145 | struct trace_cpu *tc = filp->private_data; |
a98a3c3f | 4146 | unsigned long val; |
4f271a2a | 4147 | int ret; |
a98a3c3f | 4148 | |
22fe9b54 PH |
4149 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4150 | if (ret) | |
c6caeeb1 | 4151 | return ret; |
a98a3c3f SR |
4152 | |
4153 | /* must have at least 1 entry */ | |
4154 | if (!val) | |
4155 | return -EINVAL; | |
4156 | ||
1696b2b0 SR |
4157 | /* value is in KB */ |
4158 | val <<= 10; | |
4159 | ||
2b6080f2 | 4160 | ret = tracing_resize_ring_buffer(tc->tr, val, tc->cpu); |
4f271a2a VN |
4161 | if (ret < 0) |
4162 | return ret; | |
a98a3c3f | 4163 | |
cf8517cf | 4164 | *ppos += cnt; |
a98a3c3f | 4165 | |
4f271a2a VN |
4166 | return cnt; |
4167 | } | |
bf5e6519 | 4168 | |
f81ab074 VN |
4169 | static ssize_t |
4170 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
4171 | size_t cnt, loff_t *ppos) | |
4172 | { | |
4173 | struct trace_array *tr = filp->private_data; | |
4174 | char buf[64]; | |
4175 | int r, cpu; | |
4176 | unsigned long size = 0, expanded_size = 0; | |
4177 | ||
4178 | mutex_lock(&trace_types_lock); | |
4179 | for_each_tracing_cpu(cpu) { | |
12883efb | 4180 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
4181 | if (!ring_buffer_expanded) |
4182 | expanded_size += trace_buf_size >> 10; | |
4183 | } | |
4184 | if (ring_buffer_expanded) | |
4185 | r = sprintf(buf, "%lu\n", size); | |
4186 | else | |
4187 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
4188 | mutex_unlock(&trace_types_lock); | |
4189 | ||
4190 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4191 | } | |
4192 | ||
4f271a2a VN |
4193 | static ssize_t |
4194 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
4195 | size_t cnt, loff_t *ppos) | |
4196 | { | |
4197 | /* | |
4198 | * There is no need to read what the user has written, this function | |
4199 | * is just to make sure that there is no error when "echo" is used | |
4200 | */ | |
4201 | ||
4202 | *ppos += cnt; | |
a98a3c3f SR |
4203 | |
4204 | return cnt; | |
4205 | } | |
4206 | ||
4f271a2a VN |
4207 | static int |
4208 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
4209 | { | |
2b6080f2 SR |
4210 | struct trace_array *tr = inode->i_private; |
4211 | ||
cf30cf67 SR |
4212 | /* disable tracing ? */ |
4213 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
4214 | tracing_off(); | |
4f271a2a | 4215 | /* resize the ring buffer to 0 */ |
2b6080f2 | 4216 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a VN |
4217 | |
4218 | return 0; | |
4219 | } | |
4220 | ||
5bf9a1ee PP |
4221 | static ssize_t |
4222 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
4223 | size_t cnt, loff_t *fpos) | |
4224 | { | |
d696b58c SR |
4225 | unsigned long addr = (unsigned long)ubuf; |
4226 | struct ring_buffer_event *event; | |
4227 | struct ring_buffer *buffer; | |
4228 | struct print_entry *entry; | |
4229 | unsigned long irq_flags; | |
4230 | struct page *pages[2]; | |
6edb2a8a | 4231 | void *map_page[2]; |
d696b58c SR |
4232 | int nr_pages = 1; |
4233 | ssize_t written; | |
d696b58c SR |
4234 | int offset; |
4235 | int size; | |
4236 | int len; | |
4237 | int ret; | |
6edb2a8a | 4238 | int i; |
5bf9a1ee | 4239 | |
c76f0694 | 4240 | if (tracing_disabled) |
5bf9a1ee PP |
4241 | return -EINVAL; |
4242 | ||
5224c3a3 MSB |
4243 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
4244 | return -EINVAL; | |
4245 | ||
5bf9a1ee PP |
4246 | if (cnt > TRACE_BUF_SIZE) |
4247 | cnt = TRACE_BUF_SIZE; | |
4248 | ||
d696b58c SR |
4249 | /* |
4250 | * Userspace is injecting traces into the kernel trace buffer. | |
4251 | * We want to be as non intrusive as possible. | |
4252 | * To do so, we do not want to allocate any special buffers | |
4253 | * or take any locks, but instead write the userspace data | |
4254 | * straight into the ring buffer. | |
4255 | * | |
4256 | * First we need to pin the userspace buffer into memory, | |
4257 | * which, most likely it is, because it just referenced it. | |
4258 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
4259 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
4260 | * pages directly. We then write the data directly into the | |
4261 | * ring buffer. | |
4262 | */ | |
4263 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 4264 | |
d696b58c SR |
4265 | /* check if we cross pages */ |
4266 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
4267 | nr_pages = 2; | |
4268 | ||
4269 | offset = addr & (PAGE_SIZE - 1); | |
4270 | addr &= PAGE_MASK; | |
4271 | ||
4272 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
4273 | if (ret < nr_pages) { | |
4274 | while (--ret >= 0) | |
4275 | put_page(pages[ret]); | |
4276 | written = -EFAULT; | |
4277 | goto out; | |
5bf9a1ee | 4278 | } |
d696b58c | 4279 | |
6edb2a8a SR |
4280 | for (i = 0; i < nr_pages; i++) |
4281 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
4282 | |
4283 | local_save_flags(irq_flags); | |
4284 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
12883efb | 4285 | buffer = global_trace.trace_buffer.buffer; |
d696b58c SR |
4286 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
4287 | irq_flags, preempt_count()); | |
4288 | if (!event) { | |
4289 | /* Ring buffer disabled, return as if not open for write */ | |
4290 | written = -EBADF; | |
4291 | goto out_unlock; | |
5bf9a1ee | 4292 | } |
d696b58c SR |
4293 | |
4294 | entry = ring_buffer_event_data(event); | |
4295 | entry->ip = _THIS_IP_; | |
4296 | ||
4297 | if (nr_pages == 2) { | |
4298 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
4299 | memcpy(&entry->buf, map_page[0] + offset, len); |
4300 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 4301 | } else |
6edb2a8a | 4302 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 4303 | |
d696b58c SR |
4304 | if (entry->buf[cnt - 1] != '\n') { |
4305 | entry->buf[cnt] = '\n'; | |
4306 | entry->buf[cnt + 1] = '\0'; | |
4307 | } else | |
4308 | entry->buf[cnt] = '\0'; | |
4309 | ||
7ffbd48d | 4310 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 4311 | |
d696b58c | 4312 | written = cnt; |
5bf9a1ee | 4313 | |
d696b58c | 4314 | *fpos += written; |
1aa54bca | 4315 | |
d696b58c | 4316 | out_unlock: |
6edb2a8a SR |
4317 | for (i = 0; i < nr_pages; i++){ |
4318 | kunmap_atomic(map_page[i]); | |
4319 | put_page(pages[i]); | |
4320 | } | |
d696b58c | 4321 | out: |
1aa54bca | 4322 | return written; |
5bf9a1ee PP |
4323 | } |
4324 | ||
13f16d20 | 4325 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 4326 | { |
2b6080f2 | 4327 | struct trace_array *tr = m->private; |
5079f326 Z |
4328 | int i; |
4329 | ||
4330 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 4331 | seq_printf(m, |
5079f326 | 4332 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
4333 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
4334 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 4335 | seq_putc(m, '\n'); |
5079f326 | 4336 | |
13f16d20 | 4337 | return 0; |
5079f326 Z |
4338 | } |
4339 | ||
4340 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
4341 | size_t cnt, loff_t *fpos) | |
4342 | { | |
2b6080f2 SR |
4343 | struct seq_file *m = filp->private_data; |
4344 | struct trace_array *tr = m->private; | |
5079f326 Z |
4345 | char buf[64]; |
4346 | const char *clockstr; | |
4347 | int i; | |
4348 | ||
4349 | if (cnt >= sizeof(buf)) | |
4350 | return -EINVAL; | |
4351 | ||
4352 | if (copy_from_user(&buf, ubuf, cnt)) | |
4353 | return -EFAULT; | |
4354 | ||
4355 | buf[cnt] = 0; | |
4356 | ||
4357 | clockstr = strstrip(buf); | |
4358 | ||
4359 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
4360 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
4361 | break; | |
4362 | } | |
4363 | if (i == ARRAY_SIZE(trace_clocks)) | |
4364 | return -EINVAL; | |
4365 | ||
5079f326 Z |
4366 | mutex_lock(&trace_types_lock); |
4367 | ||
2b6080f2 SR |
4368 | tr->clock_id = i; |
4369 | ||
12883efb | 4370 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 4371 | |
60303ed3 DS |
4372 | /* |
4373 | * New clock may not be consistent with the previous clock. | |
4374 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
4375 | */ | |
12883efb SRRH |
4376 | tracing_reset_online_cpus(&global_trace.trace_buffer); |
4377 | ||
4378 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4379 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) | |
4380 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); | |
4381 | tracing_reset_online_cpus(&global_trace.max_buffer); | |
4382 | #endif | |
60303ed3 | 4383 | |
5079f326 Z |
4384 | mutex_unlock(&trace_types_lock); |
4385 | ||
4386 | *fpos += cnt; | |
4387 | ||
4388 | return cnt; | |
4389 | } | |
4390 | ||
13f16d20 LZ |
4391 | static int tracing_clock_open(struct inode *inode, struct file *file) |
4392 | { | |
4393 | if (tracing_disabled) | |
4394 | return -ENODEV; | |
2b6080f2 SR |
4395 | |
4396 | return single_open(file, tracing_clock_show, inode->i_private); | |
13f16d20 LZ |
4397 | } |
4398 | ||
6de58e62 SRRH |
4399 | struct ftrace_buffer_info { |
4400 | struct trace_iterator iter; | |
4401 | void *spare; | |
4402 | unsigned int read; | |
4403 | }; | |
4404 | ||
debdd57f HT |
4405 | #ifdef CONFIG_TRACER_SNAPSHOT |
4406 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
4407 | { | |
2b6080f2 | 4408 | struct trace_cpu *tc = inode->i_private; |
debdd57f | 4409 | struct trace_iterator *iter; |
2b6080f2 | 4410 | struct seq_file *m; |
debdd57f HT |
4411 | int ret = 0; |
4412 | ||
4413 | if (file->f_mode & FMODE_READ) { | |
4414 | iter = __tracing_open(inode, file, true); | |
4415 | if (IS_ERR(iter)) | |
4416 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
4417 | } else { |
4418 | /* Writes still need the seq_file to hold the private data */ | |
4419 | m = kzalloc(sizeof(*m), GFP_KERNEL); | |
4420 | if (!m) | |
4421 | return -ENOMEM; | |
4422 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
4423 | if (!iter) { | |
4424 | kfree(m); | |
4425 | return -ENOMEM; | |
4426 | } | |
4427 | iter->tr = tc->tr; | |
12883efb | 4428 | iter->trace_buffer = &tc->tr->max_buffer; |
f1affcaa | 4429 | iter->cpu_file = tc->cpu; |
2b6080f2 SR |
4430 | m->private = iter; |
4431 | file->private_data = m; | |
debdd57f | 4432 | } |
2b6080f2 | 4433 | |
debdd57f HT |
4434 | return ret; |
4435 | } | |
4436 | ||
4437 | static ssize_t | |
4438 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4439 | loff_t *ppos) | |
4440 | { | |
2b6080f2 SR |
4441 | struct seq_file *m = filp->private_data; |
4442 | struct trace_iterator *iter = m->private; | |
4443 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
4444 | unsigned long val; |
4445 | int ret; | |
4446 | ||
4447 | ret = tracing_update_buffers(); | |
4448 | if (ret < 0) | |
4449 | return ret; | |
4450 | ||
4451 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
4452 | if (ret) | |
4453 | return ret; | |
4454 | ||
4455 | mutex_lock(&trace_types_lock); | |
4456 | ||
2b6080f2 | 4457 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
4458 | ret = -EBUSY; |
4459 | goto out; | |
4460 | } | |
4461 | ||
4462 | switch (val) { | |
4463 | case 0: | |
f1affcaa SRRH |
4464 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
4465 | ret = -EINVAL; | |
4466 | break; | |
4467 | } | |
45ad21ca | 4468 | if (tr->allocated_snapshot) { |
debdd57f | 4469 | /* free spare buffer */ |
12883efb | 4470 | ring_buffer_resize(tr->max_buffer.buffer, 1, |
debdd57f | 4471 | RING_BUFFER_ALL_CPUS); |
12883efb SRRH |
4472 | set_buffer_entries(&tr->max_buffer, 1); |
4473 | tracing_reset_online_cpus(&tr->max_buffer); | |
45ad21ca | 4474 | tr->allocated_snapshot = false; |
debdd57f HT |
4475 | } |
4476 | break; | |
4477 | case 1: | |
f1affcaa SRRH |
4478 | /* Only allow per-cpu swap if the ring buffer supports it */ |
4479 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
4480 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
4481 | ret = -EINVAL; | |
4482 | break; | |
4483 | } | |
4484 | #endif | |
45ad21ca | 4485 | if (!tr->allocated_snapshot) { |
debdd57f | 4486 | /* allocate spare buffer */ |
12883efb SRRH |
4487 | ret = resize_buffer_duplicate_size(&tr->max_buffer, |
4488 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
debdd57f HT |
4489 | if (ret < 0) |
4490 | break; | |
45ad21ca | 4491 | tr->allocated_snapshot = true; |
debdd57f | 4492 | } |
debdd57f HT |
4493 | local_irq_disable(); |
4494 | /* Now, we're going to swap */ | |
f1affcaa | 4495 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 4496 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 4497 | else |
ce9bae55 | 4498 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
4499 | local_irq_enable(); |
4500 | break; | |
4501 | default: | |
45ad21ca | 4502 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
4503 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
4504 | tracing_reset_online_cpus(&tr->max_buffer); | |
4505 | else | |
4506 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
4507 | } | |
debdd57f HT |
4508 | break; |
4509 | } | |
4510 | ||
4511 | if (ret >= 0) { | |
4512 | *ppos += cnt; | |
4513 | ret = cnt; | |
4514 | } | |
4515 | out: | |
4516 | mutex_unlock(&trace_types_lock); | |
4517 | return ret; | |
4518 | } | |
2b6080f2 SR |
4519 | |
4520 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
4521 | { | |
4522 | struct seq_file *m = file->private_data; | |
4523 | ||
4524 | if (file->f_mode & FMODE_READ) | |
4525 | return tracing_release(inode, file); | |
4526 | ||
4527 | /* If write only, the seq_file is just a stub */ | |
4528 | if (m) | |
4529 | kfree(m->private); | |
4530 | kfree(m); | |
4531 | ||
4532 | return 0; | |
4533 | } | |
4534 | ||
6de58e62 SRRH |
4535 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
4536 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4537 | size_t count, loff_t *ppos); | |
4538 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
4539 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
4540 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
4541 | ||
4542 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
4543 | { | |
4544 | struct ftrace_buffer_info *info; | |
4545 | int ret; | |
4546 | ||
4547 | ret = tracing_buffers_open(inode, filp); | |
4548 | if (ret < 0) | |
4549 | return ret; | |
4550 | ||
4551 | info = filp->private_data; | |
4552 | ||
4553 | if (info->iter.trace->use_max_tr) { | |
4554 | tracing_buffers_release(inode, filp); | |
4555 | return -EBUSY; | |
4556 | } | |
4557 | ||
4558 | info->iter.snapshot = true; | |
4559 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
4560 | ||
4561 | return ret; | |
4562 | } | |
4563 | ||
debdd57f HT |
4564 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
4565 | ||
4566 | ||
5e2336a0 | 4567 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
4568 | .open = tracing_open_generic, |
4569 | .read = tracing_max_lat_read, | |
4570 | .write = tracing_max_lat_write, | |
b444786f | 4571 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4572 | }; |
4573 | ||
5e2336a0 | 4574 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
4575 | .open = tracing_open_generic, |
4576 | .read = tracing_set_trace_read, | |
4577 | .write = tracing_set_trace_write, | |
b444786f | 4578 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4579 | }; |
4580 | ||
5e2336a0 | 4581 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 4582 | .open = tracing_open_pipe, |
2a2cc8f7 | 4583 | .poll = tracing_poll_pipe, |
4bf39a94 | 4584 | .read = tracing_read_pipe, |
3c56819b | 4585 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 4586 | .release = tracing_release_pipe, |
b444786f | 4587 | .llseek = no_llseek, |
b3806b43 SR |
4588 | }; |
4589 | ||
5e2336a0 | 4590 | static const struct file_operations tracing_entries_fops = { |
2b6080f2 | 4591 | .open = tracing_open_generic, |
a98a3c3f SR |
4592 | .read = tracing_entries_read, |
4593 | .write = tracing_entries_write, | |
b444786f | 4594 | .llseek = generic_file_llseek, |
a98a3c3f SR |
4595 | }; |
4596 | ||
f81ab074 VN |
4597 | static const struct file_operations tracing_total_entries_fops = { |
4598 | .open = tracing_open_generic, | |
4599 | .read = tracing_total_entries_read, | |
4600 | .llseek = generic_file_llseek, | |
4601 | }; | |
4602 | ||
4f271a2a VN |
4603 | static const struct file_operations tracing_free_buffer_fops = { |
4604 | .write = tracing_free_buffer_write, | |
4605 | .release = tracing_free_buffer_release, | |
4606 | }; | |
4607 | ||
5e2336a0 | 4608 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 4609 | .open = tracing_open_generic, |
5bf9a1ee | 4610 | .write = tracing_mark_write, |
b444786f | 4611 | .llseek = generic_file_llseek, |
5bf9a1ee PP |
4612 | }; |
4613 | ||
5079f326 | 4614 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
4615 | .open = tracing_clock_open, |
4616 | .read = seq_read, | |
4617 | .llseek = seq_lseek, | |
4618 | .release = single_release, | |
5079f326 Z |
4619 | .write = tracing_clock_write, |
4620 | }; | |
4621 | ||
debdd57f HT |
4622 | #ifdef CONFIG_TRACER_SNAPSHOT |
4623 | static const struct file_operations snapshot_fops = { | |
4624 | .open = tracing_snapshot_open, | |
4625 | .read = seq_read, | |
4626 | .write = tracing_snapshot_write, | |
4627 | .llseek = tracing_seek, | |
2b6080f2 | 4628 | .release = tracing_snapshot_release, |
debdd57f | 4629 | }; |
debdd57f | 4630 | |
6de58e62 SRRH |
4631 | static const struct file_operations snapshot_raw_fops = { |
4632 | .open = snapshot_raw_open, | |
4633 | .read = tracing_buffers_read, | |
4634 | .release = tracing_buffers_release, | |
4635 | .splice_read = tracing_buffers_splice_read, | |
4636 | .llseek = no_llseek, | |
2cadf913 SR |
4637 | }; |
4638 | ||
6de58e62 SRRH |
4639 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
4640 | ||
2cadf913 SR |
4641 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
4642 | { | |
2b6080f2 SR |
4643 | struct trace_cpu *tc = inode->i_private; |
4644 | struct trace_array *tr = tc->tr; | |
2cadf913 SR |
4645 | struct ftrace_buffer_info *info; |
4646 | ||
4647 | if (tracing_disabled) | |
4648 | return -ENODEV; | |
4649 | ||
4650 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
4651 | if (!info) | |
4652 | return -ENOMEM; | |
4653 | ||
a695cb58 SRRH |
4654 | mutex_lock(&trace_types_lock); |
4655 | ||
4656 | tr->ref++; | |
4657 | ||
cc60cdc9 SR |
4658 | info->iter.tr = tr; |
4659 | info->iter.cpu_file = tc->cpu; | |
b627344f | 4660 | info->iter.trace = tr->current_trace; |
12883efb | 4661 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 4662 | info->spare = NULL; |
2cadf913 | 4663 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 4664 | info->read = (unsigned int)-1; |
2cadf913 SR |
4665 | |
4666 | filp->private_data = info; | |
4667 | ||
a695cb58 SRRH |
4668 | mutex_unlock(&trace_types_lock); |
4669 | ||
d1e7e02f | 4670 | return nonseekable_open(inode, filp); |
2cadf913 SR |
4671 | } |
4672 | ||
cc60cdc9 SR |
4673 | static unsigned int |
4674 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
4675 | { | |
4676 | struct ftrace_buffer_info *info = filp->private_data; | |
4677 | struct trace_iterator *iter = &info->iter; | |
4678 | ||
4679 | return trace_poll(iter, filp, poll_table); | |
4680 | } | |
4681 | ||
2cadf913 SR |
4682 | static ssize_t |
4683 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4684 | size_t count, loff_t *ppos) | |
4685 | { | |
4686 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 4687 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 4688 | ssize_t ret; |
6de58e62 | 4689 | ssize_t size; |
2cadf913 | 4690 | |
2dc5d12b SR |
4691 | if (!count) |
4692 | return 0; | |
4693 | ||
6de58e62 SRRH |
4694 | mutex_lock(&trace_types_lock); |
4695 | ||
4696 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4697 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
4698 | size = -EBUSY; | |
4699 | goto out_unlock; | |
4700 | } | |
4701 | #endif | |
4702 | ||
ddd538f3 | 4703 | if (!info->spare) |
12883efb SRRH |
4704 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
4705 | iter->cpu_file); | |
6de58e62 | 4706 | size = -ENOMEM; |
ddd538f3 | 4707 | if (!info->spare) |
6de58e62 | 4708 | goto out_unlock; |
ddd538f3 | 4709 | |
2cadf913 SR |
4710 | /* Do we have previous read data to read? */ |
4711 | if (info->read < PAGE_SIZE) | |
4712 | goto read; | |
4713 | ||
b627344f | 4714 | again: |
cc60cdc9 | 4715 | trace_access_lock(iter->cpu_file); |
12883efb | 4716 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
4717 | &info->spare, |
4718 | count, | |
cc60cdc9 SR |
4719 | iter->cpu_file, 0); |
4720 | trace_access_unlock(iter->cpu_file); | |
b627344f SR |
4721 | |
4722 | if (ret < 0) { | |
4723 | if (trace_empty(iter)) { | |
6de58e62 SRRH |
4724 | if ((filp->f_flags & O_NONBLOCK)) { |
4725 | size = -EAGAIN; | |
4726 | goto out_unlock; | |
4727 | } | |
4728 | mutex_unlock(&trace_types_lock); | |
b627344f | 4729 | iter->trace->wait_pipe(iter); |
6de58e62 SRRH |
4730 | mutex_lock(&trace_types_lock); |
4731 | if (signal_pending(current)) { | |
4732 | size = -EINTR; | |
4733 | goto out_unlock; | |
4734 | } | |
b627344f SR |
4735 | goto again; |
4736 | } | |
6de58e62 SRRH |
4737 | size = 0; |
4738 | goto out_unlock; | |
b627344f | 4739 | } |
2cadf913 | 4740 | |
436fc280 | 4741 | info->read = 0; |
b627344f | 4742 | read: |
2cadf913 SR |
4743 | size = PAGE_SIZE - info->read; |
4744 | if (size > count) | |
4745 | size = count; | |
4746 | ||
4747 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
6de58e62 SRRH |
4748 | if (ret == size) { |
4749 | size = -EFAULT; | |
4750 | goto out_unlock; | |
4751 | } | |
2dc5d12b SR |
4752 | size -= ret; |
4753 | ||
2cadf913 SR |
4754 | *ppos += size; |
4755 | info->read += size; | |
4756 | ||
6de58e62 SRRH |
4757 | out_unlock: |
4758 | mutex_unlock(&trace_types_lock); | |
4759 | ||
2cadf913 SR |
4760 | return size; |
4761 | } | |
4762 | ||
4763 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
4764 | { | |
4765 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 4766 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 4767 | |
a695cb58 SRRH |
4768 | mutex_lock(&trace_types_lock); |
4769 | ||
4770 | WARN_ON(!iter->tr->ref); | |
4771 | iter->tr->ref--; | |
4772 | ||
ddd538f3 | 4773 | if (info->spare) |
12883efb | 4774 | ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); |
2cadf913 SR |
4775 | kfree(info); |
4776 | ||
a695cb58 SRRH |
4777 | mutex_unlock(&trace_types_lock); |
4778 | ||
2cadf913 SR |
4779 | return 0; |
4780 | } | |
4781 | ||
4782 | struct buffer_ref { | |
4783 | struct ring_buffer *buffer; | |
4784 | void *page; | |
4785 | int ref; | |
4786 | }; | |
4787 | ||
4788 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
4789 | struct pipe_buffer *buf) | |
4790 | { | |
4791 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
4792 | ||
4793 | if (--ref->ref) | |
4794 | return; | |
4795 | ||
4796 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
4797 | kfree(ref); | |
4798 | buf->private = 0; | |
4799 | } | |
4800 | ||
2cadf913 SR |
4801 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
4802 | struct pipe_buffer *buf) | |
4803 | { | |
4804 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
4805 | ||
4806 | ref->ref++; | |
4807 | } | |
4808 | ||
4809 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 4810 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
4811 | .can_merge = 0, |
4812 | .map = generic_pipe_buf_map, | |
4813 | .unmap = generic_pipe_buf_unmap, | |
4814 | .confirm = generic_pipe_buf_confirm, | |
4815 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 4816 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
4817 | .get = buffer_pipe_buf_get, |
4818 | }; | |
4819 | ||
4820 | /* | |
4821 | * Callback from splice_to_pipe(), if we need to release some pages | |
4822 | * at the end of the spd in case we error'ed out in filling the pipe. | |
4823 | */ | |
4824 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
4825 | { | |
4826 | struct buffer_ref *ref = | |
4827 | (struct buffer_ref *)spd->partial[i].private; | |
4828 | ||
4829 | if (--ref->ref) | |
4830 | return; | |
4831 | ||
4832 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
4833 | kfree(ref); | |
4834 | spd->partial[i].private = 0; | |
4835 | } | |
4836 | ||
4837 | static ssize_t | |
4838 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
4839 | struct pipe_inode_info *pipe, size_t len, | |
4840 | unsigned int flags) | |
4841 | { | |
4842 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 4843 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
4844 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
4845 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 4846 | struct splice_pipe_desc spd = { |
35f3d14d JA |
4847 | .pages = pages_def, |
4848 | .partial = partial_def, | |
047fe360 | 4849 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
4850 | .flags = flags, |
4851 | .ops = &buffer_pipe_buf_ops, | |
4852 | .spd_release = buffer_spd_release, | |
4853 | }; | |
4854 | struct buffer_ref *ref; | |
93459c6c | 4855 | int entries, size, i; |
6de58e62 | 4856 | ssize_t ret; |
2cadf913 | 4857 | |
6de58e62 SRRH |
4858 | mutex_lock(&trace_types_lock); |
4859 | ||
4860 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4861 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
4862 | ret = -EBUSY; | |
4863 | goto out; | |
4864 | } | |
4865 | #endif | |
4866 | ||
4867 | if (splice_grow_spd(pipe, &spd)) { | |
4868 | ret = -ENOMEM; | |
4869 | goto out; | |
4870 | } | |
35f3d14d | 4871 | |
93cfb3c9 | 4872 | if (*ppos & (PAGE_SIZE - 1)) { |
35f3d14d JA |
4873 | ret = -EINVAL; |
4874 | goto out; | |
93cfb3c9 LJ |
4875 | } |
4876 | ||
4877 | if (len & (PAGE_SIZE - 1)) { | |
35f3d14d JA |
4878 | if (len < PAGE_SIZE) { |
4879 | ret = -EINVAL; | |
4880 | goto out; | |
4881 | } | |
93cfb3c9 LJ |
4882 | len &= PAGE_MASK; |
4883 | } | |
4884 | ||
cc60cdc9 SR |
4885 | again: |
4886 | trace_access_lock(iter->cpu_file); | |
12883efb | 4887 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 4888 | |
35f3d14d | 4889 | for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
4890 | struct page *page; |
4891 | int r; | |
4892 | ||
4893 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
4894 | if (!ref) | |
4895 | break; | |
4896 | ||
7267fa68 | 4897 | ref->ref = 1; |
12883efb | 4898 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 4899 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
2cadf913 SR |
4900 | if (!ref->page) { |
4901 | kfree(ref); | |
4902 | break; | |
4903 | } | |
4904 | ||
4905 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 4906 | len, iter->cpu_file, 1); |
2cadf913 | 4907 | if (r < 0) { |
7ea59064 | 4908 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
4909 | kfree(ref); |
4910 | break; | |
4911 | } | |
4912 | ||
4913 | /* | |
4914 | * zero out any left over data, this is going to | |
4915 | * user land. | |
4916 | */ | |
4917 | size = ring_buffer_page_len(ref->page); | |
4918 | if (size < PAGE_SIZE) | |
4919 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
4920 | ||
4921 | page = virt_to_page(ref->page); | |
4922 | ||
4923 | spd.pages[i] = page; | |
4924 | spd.partial[i].len = PAGE_SIZE; | |
4925 | spd.partial[i].offset = 0; | |
4926 | spd.partial[i].private = (unsigned long)ref; | |
4927 | spd.nr_pages++; | |
93cfb3c9 | 4928 | *ppos += PAGE_SIZE; |
93459c6c | 4929 | |
12883efb | 4930 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
4931 | } |
4932 | ||
cc60cdc9 | 4933 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
4934 | spd.nr_pages = i; |
4935 | ||
4936 | /* did we read anything? */ | |
4937 | if (!spd.nr_pages) { | |
cc60cdc9 | 4938 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) { |
2cadf913 | 4939 | ret = -EAGAIN; |
cc60cdc9 SR |
4940 | goto out; |
4941 | } | |
6de58e62 | 4942 | mutex_unlock(&trace_types_lock); |
b627344f | 4943 | iter->trace->wait_pipe(iter); |
6de58e62 | 4944 | mutex_lock(&trace_types_lock); |
cc60cdc9 SR |
4945 | if (signal_pending(current)) { |
4946 | ret = -EINTR; | |
4947 | goto out; | |
4948 | } | |
4949 | goto again; | |
2cadf913 SR |
4950 | } |
4951 | ||
4952 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 4953 | splice_shrink_spd(&spd); |
35f3d14d | 4954 | out: |
6de58e62 SRRH |
4955 | mutex_unlock(&trace_types_lock); |
4956 | ||
2cadf913 SR |
4957 | return ret; |
4958 | } | |
4959 | ||
4960 | static const struct file_operations tracing_buffers_fops = { | |
4961 | .open = tracing_buffers_open, | |
4962 | .read = tracing_buffers_read, | |
cc60cdc9 | 4963 | .poll = tracing_buffers_poll, |
2cadf913 SR |
4964 | .release = tracing_buffers_release, |
4965 | .splice_read = tracing_buffers_splice_read, | |
4966 | .llseek = no_llseek, | |
4967 | }; | |
4968 | ||
c8d77183 SR |
4969 | static ssize_t |
4970 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
4971 | size_t count, loff_t *ppos) | |
4972 | { | |
2b6080f2 SR |
4973 | struct trace_cpu *tc = filp->private_data; |
4974 | struct trace_array *tr = tc->tr; | |
12883efb | 4975 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
c8d77183 SR |
4976 | struct trace_seq *s; |
4977 | unsigned long cnt; | |
c64e148a VN |
4978 | unsigned long long t; |
4979 | unsigned long usec_rem; | |
2b6080f2 | 4980 | int cpu = tc->cpu; |
c8d77183 | 4981 | |
e4f2d10f | 4982 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 4983 | if (!s) |
a646365c | 4984 | return -ENOMEM; |
c8d77183 SR |
4985 | |
4986 | trace_seq_init(s); | |
4987 | ||
12883efb | 4988 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
4989 | trace_seq_printf(s, "entries: %ld\n", cnt); |
4990 | ||
12883efb | 4991 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
4992 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
4993 | ||
12883efb | 4994 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
4995 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
4996 | ||
12883efb | 4997 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
4998 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
4999 | ||
11043d8b YY |
5000 | if (trace_clocks[trace_clock_id].in_ns) { |
5001 | /* local or global for trace_clock */ | |
12883efb | 5002 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
5003 | usec_rem = do_div(t, USEC_PER_SEC); |
5004 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
5005 | t, usec_rem); | |
5006 | ||
12883efb | 5007 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
5008 | usec_rem = do_div(t, USEC_PER_SEC); |
5009 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
5010 | } else { | |
5011 | /* counter or tsc mode for trace_clock */ | |
5012 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 5013 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 5014 | |
11043d8b | 5015 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 5016 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 5017 | } |
c64e148a | 5018 | |
12883efb | 5019 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
5020 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
5021 | ||
12883efb | 5022 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
5023 | trace_seq_printf(s, "read events: %ld\n", cnt); |
5024 | ||
c8d77183 SR |
5025 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
5026 | ||
5027 | kfree(s); | |
5028 | ||
5029 | return count; | |
5030 | } | |
5031 | ||
5032 | static const struct file_operations tracing_stats_fops = { | |
5033 | .open = tracing_open_generic, | |
5034 | .read = tracing_stats_read, | |
b444786f | 5035 | .llseek = generic_file_llseek, |
c8d77183 SR |
5036 | }; |
5037 | ||
bc0c38d1 SR |
5038 | #ifdef CONFIG_DYNAMIC_FTRACE |
5039 | ||
b807c3d0 SR |
5040 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
5041 | { | |
5042 | return 0; | |
5043 | } | |
5044 | ||
bc0c38d1 | 5045 | static ssize_t |
b807c3d0 | 5046 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
5047 | size_t cnt, loff_t *ppos) |
5048 | { | |
a26a2a27 SR |
5049 | static char ftrace_dyn_info_buffer[1024]; |
5050 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 5051 | unsigned long *p = filp->private_data; |
b807c3d0 | 5052 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 5053 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
5054 | int r; |
5055 | ||
b807c3d0 SR |
5056 | mutex_lock(&dyn_info_mutex); |
5057 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 5058 | |
a26a2a27 | 5059 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
5060 | buf[r++] = '\n'; |
5061 | ||
5062 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5063 | ||
5064 | mutex_unlock(&dyn_info_mutex); | |
5065 | ||
5066 | return r; | |
bc0c38d1 SR |
5067 | } |
5068 | ||
5e2336a0 | 5069 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 5070 | .open = tracing_open_generic, |
b807c3d0 | 5071 | .read = tracing_read_dyn_info, |
b444786f | 5072 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5073 | }; |
5074 | #endif | |
5075 | ||
2b6080f2 | 5076 | struct dentry *tracing_init_dentry_tr(struct trace_array *tr) |
bc0c38d1 SR |
5077 | { |
5078 | static int once; | |
5079 | ||
2b6080f2 SR |
5080 | if (tr->dir) |
5081 | return tr->dir; | |
bc0c38d1 | 5082 | |
3e1f60b8 FW |
5083 | if (!debugfs_initialized()) |
5084 | return NULL; | |
5085 | ||
2b6080f2 SR |
5086 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) |
5087 | tr->dir = debugfs_create_dir("tracing", NULL); | |
bc0c38d1 | 5088 | |
2b6080f2 | 5089 | if (!tr->dir && !once) { |
bc0c38d1 SR |
5090 | once = 1; |
5091 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
5092 | return NULL; | |
5093 | } | |
5094 | ||
2b6080f2 | 5095 | return tr->dir; |
bc0c38d1 SR |
5096 | } |
5097 | ||
2b6080f2 SR |
5098 | struct dentry *tracing_init_dentry(void) |
5099 | { | |
5100 | return tracing_init_dentry_tr(&global_trace); | |
5101 | } | |
b04cc6b1 | 5102 | |
2b6080f2 | 5103 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 5104 | { |
b04cc6b1 FW |
5105 | struct dentry *d_tracer; |
5106 | ||
2b6080f2 SR |
5107 | if (tr->percpu_dir) |
5108 | return tr->percpu_dir; | |
b04cc6b1 | 5109 | |
2b6080f2 | 5110 | d_tracer = tracing_init_dentry_tr(tr); |
b04cc6b1 FW |
5111 | if (!d_tracer) |
5112 | return NULL; | |
5113 | ||
2b6080f2 | 5114 | tr->percpu_dir = debugfs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 5115 | |
2b6080f2 SR |
5116 | WARN_ONCE(!tr->percpu_dir, |
5117 | "Could not create debugfs directory 'per_cpu/%d'\n", cpu); | |
b04cc6b1 | 5118 | |
2b6080f2 | 5119 | return tr->percpu_dir; |
b04cc6b1 FW |
5120 | } |
5121 | ||
2b6080f2 SR |
5122 | static void |
5123 | tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) | |
b04cc6b1 | 5124 | { |
12883efb | 5125 | struct trace_array_cpu *data = per_cpu_ptr(tr->trace_buffer.data, cpu); |
2b6080f2 | 5126 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 5127 | struct dentry *d_cpu; |
dd49a38c | 5128 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 5129 | |
0a3d7ce7 NK |
5130 | if (!d_percpu) |
5131 | return; | |
5132 | ||
dd49a38c | 5133 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
5134 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
5135 | if (!d_cpu) { | |
5136 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
5137 | return; | |
5138 | } | |
b04cc6b1 | 5139 | |
8656e7a2 | 5140 | /* per cpu trace_pipe */ |
5452af66 | 5141 | trace_create_file("trace_pipe", 0444, d_cpu, |
2b6080f2 | 5142 | (void *)&data->trace_cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
5143 | |
5144 | /* per cpu trace */ | |
5452af66 | 5145 | trace_create_file("trace", 0644, d_cpu, |
2b6080f2 | 5146 | (void *)&data->trace_cpu, &tracing_fops); |
7f96f93f | 5147 | |
5452af66 | 5148 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
2b6080f2 | 5149 | (void *)&data->trace_cpu, &tracing_buffers_fops); |
7f96f93f | 5150 | |
c8d77183 | 5151 | trace_create_file("stats", 0444, d_cpu, |
2b6080f2 | 5152 | (void *)&data->trace_cpu, &tracing_stats_fops); |
438ced17 VN |
5153 | |
5154 | trace_create_file("buffer_size_kb", 0444, d_cpu, | |
2b6080f2 | 5155 | (void *)&data->trace_cpu, &tracing_entries_fops); |
f1affcaa SRRH |
5156 | |
5157 | #ifdef CONFIG_TRACER_SNAPSHOT | |
5158 | trace_create_file("snapshot", 0644, d_cpu, | |
5159 | (void *)&data->trace_cpu, &snapshot_fops); | |
6de58e62 SRRH |
5160 | |
5161 | trace_create_file("snapshot_raw", 0444, d_cpu, | |
5162 | (void *)&data->trace_cpu, &snapshot_raw_fops); | |
f1affcaa | 5163 | #endif |
b04cc6b1 FW |
5164 | } |
5165 | ||
60a11774 SR |
5166 | #ifdef CONFIG_FTRACE_SELFTEST |
5167 | /* Let selftest have access to static functions in this file */ | |
5168 | #include "trace_selftest.c" | |
5169 | #endif | |
5170 | ||
577b785f SR |
5171 | struct trace_option_dentry { |
5172 | struct tracer_opt *opt; | |
5173 | struct tracer_flags *flags; | |
2b6080f2 | 5174 | struct trace_array *tr; |
577b785f SR |
5175 | struct dentry *entry; |
5176 | }; | |
5177 | ||
5178 | static ssize_t | |
5179 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5180 | loff_t *ppos) | |
5181 | { | |
5182 | struct trace_option_dentry *topt = filp->private_data; | |
5183 | char *buf; | |
5184 | ||
5185 | if (topt->flags->val & topt->opt->bit) | |
5186 | buf = "1\n"; | |
5187 | else | |
5188 | buf = "0\n"; | |
5189 | ||
5190 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5191 | } | |
5192 | ||
5193 | static ssize_t | |
5194 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5195 | loff_t *ppos) | |
5196 | { | |
5197 | struct trace_option_dentry *topt = filp->private_data; | |
5198 | unsigned long val; | |
577b785f SR |
5199 | int ret; |
5200 | ||
22fe9b54 PH |
5201 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5202 | if (ret) | |
577b785f SR |
5203 | return ret; |
5204 | ||
8d18eaaf LZ |
5205 | if (val != 0 && val != 1) |
5206 | return -EINVAL; | |
577b785f | 5207 | |
8d18eaaf | 5208 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 5209 | mutex_lock(&trace_types_lock); |
2b6080f2 | 5210 | ret = __set_tracer_option(topt->tr->current_trace, topt->flags, |
c757bea9 | 5211 | topt->opt, !val); |
577b785f SR |
5212 | mutex_unlock(&trace_types_lock); |
5213 | if (ret) | |
5214 | return ret; | |
577b785f SR |
5215 | } |
5216 | ||
5217 | *ppos += cnt; | |
5218 | ||
5219 | return cnt; | |
5220 | } | |
5221 | ||
5222 | ||
5223 | static const struct file_operations trace_options_fops = { | |
5224 | .open = tracing_open_generic, | |
5225 | .read = trace_options_read, | |
5226 | .write = trace_options_write, | |
b444786f | 5227 | .llseek = generic_file_llseek, |
577b785f SR |
5228 | }; |
5229 | ||
a8259075 SR |
5230 | static ssize_t |
5231 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5232 | loff_t *ppos) | |
5233 | { | |
5234 | long index = (long)filp->private_data; | |
5235 | char *buf; | |
5236 | ||
5237 | if (trace_flags & (1 << index)) | |
5238 | buf = "1\n"; | |
5239 | else | |
5240 | buf = "0\n"; | |
5241 | ||
5242 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5243 | } | |
5244 | ||
5245 | static ssize_t | |
5246 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5247 | loff_t *ppos) | |
5248 | { | |
2b6080f2 | 5249 | struct trace_array *tr = &global_trace; |
a8259075 | 5250 | long index = (long)filp->private_data; |
a8259075 SR |
5251 | unsigned long val; |
5252 | int ret; | |
5253 | ||
22fe9b54 PH |
5254 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5255 | if (ret) | |
a8259075 SR |
5256 | return ret; |
5257 | ||
f2d84b65 | 5258 | if (val != 0 && val != 1) |
a8259075 | 5259 | return -EINVAL; |
69d34da2 SRRH |
5260 | |
5261 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 5262 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 5263 | mutex_unlock(&trace_types_lock); |
a8259075 | 5264 | |
613f04a0 SRRH |
5265 | if (ret < 0) |
5266 | return ret; | |
5267 | ||
a8259075 SR |
5268 | *ppos += cnt; |
5269 | ||
5270 | return cnt; | |
5271 | } | |
5272 | ||
a8259075 SR |
5273 | static const struct file_operations trace_options_core_fops = { |
5274 | .open = tracing_open_generic, | |
5275 | .read = trace_options_core_read, | |
5276 | .write = trace_options_core_write, | |
b444786f | 5277 | .llseek = generic_file_llseek, |
a8259075 SR |
5278 | }; |
5279 | ||
5452af66 | 5280 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 5281 | umode_t mode, |
5452af66 FW |
5282 | struct dentry *parent, |
5283 | void *data, | |
5284 | const struct file_operations *fops) | |
5285 | { | |
5286 | struct dentry *ret; | |
5287 | ||
5288 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
5289 | if (!ret) | |
5290 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
5291 | ||
5292 | return ret; | |
5293 | } | |
5294 | ||
5295 | ||
2b6080f2 | 5296 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
5297 | { |
5298 | struct dentry *d_tracer; | |
a8259075 | 5299 | |
2b6080f2 SR |
5300 | if (tr->options) |
5301 | return tr->options; | |
a8259075 | 5302 | |
2b6080f2 | 5303 | d_tracer = tracing_init_dentry_tr(tr); |
a8259075 SR |
5304 | if (!d_tracer) |
5305 | return NULL; | |
5306 | ||
2b6080f2 SR |
5307 | tr->options = debugfs_create_dir("options", d_tracer); |
5308 | if (!tr->options) { | |
a8259075 SR |
5309 | pr_warning("Could not create debugfs directory 'options'\n"); |
5310 | return NULL; | |
5311 | } | |
5312 | ||
2b6080f2 | 5313 | return tr->options; |
a8259075 SR |
5314 | } |
5315 | ||
577b785f | 5316 | static void |
2b6080f2 SR |
5317 | create_trace_option_file(struct trace_array *tr, |
5318 | struct trace_option_dentry *topt, | |
577b785f SR |
5319 | struct tracer_flags *flags, |
5320 | struct tracer_opt *opt) | |
5321 | { | |
5322 | struct dentry *t_options; | |
577b785f | 5323 | |
2b6080f2 | 5324 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
5325 | if (!t_options) |
5326 | return; | |
5327 | ||
5328 | topt->flags = flags; | |
5329 | topt->opt = opt; | |
2b6080f2 | 5330 | topt->tr = tr; |
577b785f | 5331 | |
5452af66 | 5332 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
5333 | &trace_options_fops); |
5334 | ||
577b785f SR |
5335 | } |
5336 | ||
5337 | static struct trace_option_dentry * | |
2b6080f2 | 5338 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
5339 | { |
5340 | struct trace_option_dentry *topts; | |
5341 | struct tracer_flags *flags; | |
5342 | struct tracer_opt *opts; | |
5343 | int cnt; | |
5344 | ||
5345 | if (!tracer) | |
5346 | return NULL; | |
5347 | ||
5348 | flags = tracer->flags; | |
5349 | ||
5350 | if (!flags || !flags->opts) | |
5351 | return NULL; | |
5352 | ||
5353 | opts = flags->opts; | |
5354 | ||
5355 | for (cnt = 0; opts[cnt].name; cnt++) | |
5356 | ; | |
5357 | ||
0cfe8245 | 5358 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
5359 | if (!topts) |
5360 | return NULL; | |
5361 | ||
5362 | for (cnt = 0; opts[cnt].name; cnt++) | |
2b6080f2 | 5363 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f SR |
5364 | &opts[cnt]); |
5365 | ||
5366 | return topts; | |
5367 | } | |
5368 | ||
5369 | static void | |
5370 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
5371 | { | |
5372 | int cnt; | |
5373 | ||
5374 | if (!topts) | |
5375 | return; | |
5376 | ||
5377 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
5378 | if (topts[cnt].entry) | |
5379 | debugfs_remove(topts[cnt].entry); | |
5380 | } | |
5381 | ||
5382 | kfree(topts); | |
5383 | } | |
5384 | ||
a8259075 | 5385 | static struct dentry * |
2b6080f2 SR |
5386 | create_trace_option_core_file(struct trace_array *tr, |
5387 | const char *option, long index) | |
a8259075 SR |
5388 | { |
5389 | struct dentry *t_options; | |
a8259075 | 5390 | |
2b6080f2 | 5391 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5392 | if (!t_options) |
5393 | return NULL; | |
5394 | ||
5452af66 | 5395 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 5396 | &trace_options_core_fops); |
a8259075 SR |
5397 | } |
5398 | ||
2b6080f2 | 5399 | static __init void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
5400 | { |
5401 | struct dentry *t_options; | |
a8259075 SR |
5402 | int i; |
5403 | ||
2b6080f2 | 5404 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5405 | if (!t_options) |
5406 | return; | |
5407 | ||
5452af66 | 5408 | for (i = 0; trace_options[i]; i++) |
2b6080f2 | 5409 | create_trace_option_core_file(tr, trace_options[i], i); |
a8259075 SR |
5410 | } |
5411 | ||
499e5470 SR |
5412 | static ssize_t |
5413 | rb_simple_read(struct file *filp, char __user *ubuf, | |
5414 | size_t cnt, loff_t *ppos) | |
5415 | { | |
348f0fc2 | 5416 | struct trace_array *tr = filp->private_data; |
12883efb | 5417 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
5418 | char buf[64]; |
5419 | int r; | |
5420 | ||
5421 | if (buffer) | |
5422 | r = ring_buffer_record_is_on(buffer); | |
5423 | else | |
5424 | r = 0; | |
5425 | ||
5426 | r = sprintf(buf, "%d\n", r); | |
5427 | ||
5428 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5429 | } | |
5430 | ||
5431 | static ssize_t | |
5432 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
5433 | size_t cnt, loff_t *ppos) | |
5434 | { | |
348f0fc2 | 5435 | struct trace_array *tr = filp->private_data; |
12883efb | 5436 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
5437 | unsigned long val; |
5438 | int ret; | |
5439 | ||
5440 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5441 | if (ret) | |
5442 | return ret; | |
5443 | ||
5444 | if (buffer) { | |
2df8f8a6 SR |
5445 | mutex_lock(&trace_types_lock); |
5446 | if (val) { | |
499e5470 | 5447 | ring_buffer_record_on(buffer); |
2b6080f2 SR |
5448 | if (tr->current_trace->start) |
5449 | tr->current_trace->start(tr); | |
2df8f8a6 | 5450 | } else { |
499e5470 | 5451 | ring_buffer_record_off(buffer); |
2b6080f2 SR |
5452 | if (tr->current_trace->stop) |
5453 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
5454 | } |
5455 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
5456 | } |
5457 | ||
5458 | (*ppos)++; | |
5459 | ||
5460 | return cnt; | |
5461 | } | |
5462 | ||
5463 | static const struct file_operations rb_simple_fops = { | |
5464 | .open = tracing_open_generic, | |
5465 | .read = rb_simple_read, | |
5466 | .write = rb_simple_write, | |
5467 | .llseek = default_llseek, | |
5468 | }; | |
5469 | ||
277ba044 SR |
5470 | struct dentry *trace_instance_dir; |
5471 | ||
5472 | static void | |
5473 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer); | |
5474 | ||
737223fb SRRH |
5475 | static void init_trace_buffers(struct trace_array *tr, struct trace_buffer *buf) |
5476 | { | |
5477 | int cpu; | |
5478 | ||
5479 | for_each_tracing_cpu(cpu) { | |
5480 | memset(per_cpu_ptr(buf->data, cpu), 0, sizeof(struct trace_array_cpu)); | |
5481 | per_cpu_ptr(buf->data, cpu)->trace_cpu.cpu = cpu; | |
5482 | per_cpu_ptr(buf->data, cpu)->trace_cpu.tr = tr; | |
5483 | } | |
5484 | } | |
5485 | ||
55034cd6 SRRH |
5486 | static int |
5487 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
5488 | { |
5489 | enum ring_buffer_flags rb_flags; | |
737223fb SRRH |
5490 | |
5491 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; | |
5492 | ||
55034cd6 SRRH |
5493 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
5494 | if (!buf->buffer) | |
5495 | return -ENOMEM; | |
737223fb | 5496 | |
55034cd6 SRRH |
5497 | buf->data = alloc_percpu(struct trace_array_cpu); |
5498 | if (!buf->data) { | |
5499 | ring_buffer_free(buf->buffer); | |
5500 | return -ENOMEM; | |
5501 | } | |
737223fb | 5502 | |
55034cd6 | 5503 | init_trace_buffers(tr, buf); |
737223fb SRRH |
5504 | |
5505 | /* Allocate the first page for all buffers */ | |
5506 | set_buffer_entries(&tr->trace_buffer, | |
5507 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
5508 | ||
55034cd6 SRRH |
5509 | return 0; |
5510 | } | |
737223fb | 5511 | |
55034cd6 SRRH |
5512 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
5513 | { | |
5514 | int ret; | |
737223fb | 5515 | |
55034cd6 SRRH |
5516 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
5517 | if (ret) | |
5518 | return ret; | |
737223fb | 5519 | |
55034cd6 SRRH |
5520 | #ifdef CONFIG_TRACER_MAX_TRACE |
5521 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
5522 | allocate_snapshot ? size : 1); | |
5523 | if (WARN_ON(ret)) { | |
737223fb | 5524 | ring_buffer_free(tr->trace_buffer.buffer); |
55034cd6 SRRH |
5525 | free_percpu(tr->trace_buffer.data); |
5526 | return -ENOMEM; | |
5527 | } | |
5528 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 5529 | |
55034cd6 SRRH |
5530 | /* |
5531 | * Only the top level trace array gets its snapshot allocated | |
5532 | * from the kernel command line. | |
5533 | */ | |
5534 | allocate_snapshot = false; | |
737223fb | 5535 | #endif |
55034cd6 | 5536 | return 0; |
737223fb SRRH |
5537 | } |
5538 | ||
5539 | static int new_instance_create(const char *name) | |
5540 | { | |
277ba044 SR |
5541 | struct trace_array *tr; |
5542 | int ret; | |
277ba044 SR |
5543 | |
5544 | mutex_lock(&trace_types_lock); | |
5545 | ||
5546 | ret = -EEXIST; | |
5547 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
5548 | if (tr->name && strcmp(tr->name, name) == 0) | |
5549 | goto out_unlock; | |
5550 | } | |
5551 | ||
5552 | ret = -ENOMEM; | |
5553 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
5554 | if (!tr) | |
5555 | goto out_unlock; | |
5556 | ||
5557 | tr->name = kstrdup(name, GFP_KERNEL); | |
5558 | if (!tr->name) | |
5559 | goto out_free_tr; | |
5560 | ||
5561 | raw_spin_lock_init(&tr->start_lock); | |
5562 | ||
5563 | tr->current_trace = &nop_trace; | |
5564 | ||
5565 | INIT_LIST_HEAD(&tr->systems); | |
5566 | INIT_LIST_HEAD(&tr->events); | |
5567 | ||
737223fb | 5568 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
5569 | goto out_free_tr; |
5570 | ||
277ba044 SR |
5571 | /* Holder for file callbacks */ |
5572 | tr->trace_cpu.cpu = RING_BUFFER_ALL_CPUS; | |
5573 | tr->trace_cpu.tr = tr; | |
5574 | ||
5575 | tr->dir = debugfs_create_dir(name, trace_instance_dir); | |
5576 | if (!tr->dir) | |
5577 | goto out_free_tr; | |
5578 | ||
5579 | ret = event_trace_add_tracer(tr->dir, tr); | |
5580 | if (ret) | |
5581 | goto out_free_tr; | |
5582 | ||
5583 | init_tracer_debugfs(tr, tr->dir); | |
5584 | ||
5585 | list_add(&tr->list, &ftrace_trace_arrays); | |
5586 | ||
5587 | mutex_unlock(&trace_types_lock); | |
5588 | ||
5589 | return 0; | |
5590 | ||
5591 | out_free_tr: | |
12883efb SRRH |
5592 | if (tr->trace_buffer.buffer) |
5593 | ring_buffer_free(tr->trace_buffer.buffer); | |
277ba044 SR |
5594 | kfree(tr->name); |
5595 | kfree(tr); | |
5596 | ||
5597 | out_unlock: | |
5598 | mutex_unlock(&trace_types_lock); | |
5599 | ||
5600 | return ret; | |
5601 | ||
5602 | } | |
5603 | ||
0c8916c3 SR |
5604 | static int instance_delete(const char *name) |
5605 | { | |
5606 | struct trace_array *tr; | |
5607 | int found = 0; | |
5608 | int ret; | |
5609 | ||
5610 | mutex_lock(&trace_types_lock); | |
5611 | ||
5612 | ret = -ENODEV; | |
5613 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
5614 | if (tr->name && strcmp(tr->name, name) == 0) { | |
5615 | found = 1; | |
5616 | break; | |
5617 | } | |
5618 | } | |
5619 | if (!found) | |
5620 | goto out_unlock; | |
5621 | ||
a695cb58 SRRH |
5622 | ret = -EBUSY; |
5623 | if (tr->ref) | |
5624 | goto out_unlock; | |
5625 | ||
0c8916c3 SR |
5626 | list_del(&tr->list); |
5627 | ||
5628 | event_trace_del_tracer(tr); | |
5629 | debugfs_remove_recursive(tr->dir); | |
12883efb SRRH |
5630 | free_percpu(tr->trace_buffer.data); |
5631 | ring_buffer_free(tr->trace_buffer.buffer); | |
0c8916c3 SR |
5632 | |
5633 | kfree(tr->name); | |
5634 | kfree(tr); | |
5635 | ||
5636 | ret = 0; | |
5637 | ||
5638 | out_unlock: | |
5639 | mutex_unlock(&trace_types_lock); | |
5640 | ||
5641 | return ret; | |
5642 | } | |
5643 | ||
277ba044 SR |
5644 | static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t mode) |
5645 | { | |
5646 | struct dentry *parent; | |
5647 | int ret; | |
5648 | ||
5649 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
5650 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
5651 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
5652 | return -ENOENT; | |
5653 | ||
5654 | /* | |
5655 | * The inode mutex is locked, but debugfs_create_dir() will also | |
5656 | * take the mutex. As the instances directory can not be destroyed | |
5657 | * or changed in any other way, it is safe to unlock it, and | |
5658 | * let the dentry try. If two users try to make the same dir at | |
5659 | * the same time, then the new_instance_create() will determine the | |
5660 | * winner. | |
5661 | */ | |
5662 | mutex_unlock(&inode->i_mutex); | |
5663 | ||
5664 | ret = new_instance_create(dentry->d_iname); | |
5665 | ||
5666 | mutex_lock(&inode->i_mutex); | |
5667 | ||
5668 | return ret; | |
5669 | } | |
5670 | ||
0c8916c3 SR |
5671 | static int instance_rmdir(struct inode *inode, struct dentry *dentry) |
5672 | { | |
5673 | struct dentry *parent; | |
5674 | int ret; | |
5675 | ||
5676 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
5677 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
5678 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
5679 | return -ENOENT; | |
5680 | ||
5681 | /* The caller did a dget() on dentry */ | |
5682 | mutex_unlock(&dentry->d_inode->i_mutex); | |
5683 | ||
5684 | /* | |
5685 | * The inode mutex is locked, but debugfs_create_dir() will also | |
5686 | * take the mutex. As the instances directory can not be destroyed | |
5687 | * or changed in any other way, it is safe to unlock it, and | |
5688 | * let the dentry try. If two users try to make the same dir at | |
5689 | * the same time, then the instance_delete() will determine the | |
5690 | * winner. | |
5691 | */ | |
5692 | mutex_unlock(&inode->i_mutex); | |
5693 | ||
5694 | ret = instance_delete(dentry->d_iname); | |
5695 | ||
5696 | mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); | |
5697 | mutex_lock(&dentry->d_inode->i_mutex); | |
5698 | ||
5699 | return ret; | |
5700 | } | |
5701 | ||
277ba044 SR |
5702 | static const struct inode_operations instance_dir_inode_operations = { |
5703 | .lookup = simple_lookup, | |
5704 | .mkdir = instance_mkdir, | |
0c8916c3 | 5705 | .rmdir = instance_rmdir, |
277ba044 SR |
5706 | }; |
5707 | ||
5708 | static __init void create_trace_instances(struct dentry *d_tracer) | |
5709 | { | |
5710 | trace_instance_dir = debugfs_create_dir("instances", d_tracer); | |
5711 | if (WARN_ON(!trace_instance_dir)) | |
5712 | return; | |
5713 | ||
5714 | /* Hijack the dir inode operations, to allow mkdir */ | |
5715 | trace_instance_dir->d_inode->i_op = &instance_dir_inode_operations; | |
5716 | } | |
5717 | ||
2b6080f2 SR |
5718 | static void |
5719 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) | |
5720 | { | |
121aaee7 | 5721 | int cpu; |
2b6080f2 SR |
5722 | |
5723 | trace_create_file("trace_options", 0644, d_tracer, | |
5724 | tr, &tracing_iter_fops); | |
5725 | ||
5726 | trace_create_file("trace", 0644, d_tracer, | |
5727 | (void *)&tr->trace_cpu, &tracing_fops); | |
5728 | ||
5729 | trace_create_file("trace_pipe", 0444, d_tracer, | |
5730 | (void *)&tr->trace_cpu, &tracing_pipe_fops); | |
5731 | ||
5732 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
5733 | (void *)&tr->trace_cpu, &tracing_entries_fops); | |
5734 | ||
5735 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
5736 | tr, &tracing_total_entries_fops); | |
5737 | ||
5738 | trace_create_file("free_buffer", 0644, d_tracer, | |
5739 | tr, &tracing_free_buffer_fops); | |
5740 | ||
5741 | trace_create_file("trace_marker", 0220, d_tracer, | |
5742 | tr, &tracing_mark_fops); | |
5743 | ||
5744 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
5745 | &trace_clock_fops); | |
5746 | ||
5747 | trace_create_file("tracing_on", 0644, d_tracer, | |
5748 | tr, &rb_simple_fops); | |
ce9bae55 SRRH |
5749 | |
5750 | #ifdef CONFIG_TRACER_SNAPSHOT | |
5751 | trace_create_file("snapshot", 0644, d_tracer, | |
5752 | (void *)&tr->trace_cpu, &snapshot_fops); | |
5753 | #endif | |
121aaee7 SRRH |
5754 | |
5755 | for_each_tracing_cpu(cpu) | |
5756 | tracing_init_debugfs_percpu(tr, cpu); | |
5757 | ||
2b6080f2 SR |
5758 | } |
5759 | ||
b5ad384e | 5760 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
5761 | { |
5762 | struct dentry *d_tracer; | |
bc0c38d1 | 5763 | |
7e53bd42 LJ |
5764 | trace_access_lock_init(); |
5765 | ||
bc0c38d1 SR |
5766 | d_tracer = tracing_init_dentry(); |
5767 | ||
2b6080f2 | 5768 | init_tracer_debugfs(&global_trace, d_tracer); |
bc0c38d1 | 5769 | |
5452af66 | 5770 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
2b6080f2 | 5771 | &global_trace, &tracing_cpumask_fops); |
a8259075 | 5772 | |
5452af66 FW |
5773 | trace_create_file("available_tracers", 0444, d_tracer, |
5774 | &global_trace, &show_traces_fops); | |
5775 | ||
339ae5d3 | 5776 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
5777 | &global_trace, &set_tracer_fops); |
5778 | ||
5d4a9dba | 5779 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
5780 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
5781 | &tracing_max_latency, &tracing_max_lat_fops); | |
0e950173 | 5782 | #endif |
5452af66 FW |
5783 | |
5784 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
5785 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 5786 | |
339ae5d3 | 5787 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
5788 | NULL, &tracing_readme_fops); |
5789 | ||
69abe6a5 AP |
5790 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
5791 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 5792 | |
bc0c38d1 | 5793 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
5794 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
5795 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 5796 | #endif |
b04cc6b1 | 5797 | |
277ba044 SR |
5798 | create_trace_instances(d_tracer); |
5799 | ||
2b6080f2 | 5800 | create_trace_options_dir(&global_trace); |
5452af66 | 5801 | |
b5ad384e | 5802 | return 0; |
bc0c38d1 SR |
5803 | } |
5804 | ||
3f5a54e3 SR |
5805 | static int trace_panic_handler(struct notifier_block *this, |
5806 | unsigned long event, void *unused) | |
5807 | { | |
944ac425 | 5808 | if (ftrace_dump_on_oops) |
cecbca96 | 5809 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
5810 | return NOTIFY_OK; |
5811 | } | |
5812 | ||
5813 | static struct notifier_block trace_panic_notifier = { | |
5814 | .notifier_call = trace_panic_handler, | |
5815 | .next = NULL, | |
5816 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
5817 | }; | |
5818 | ||
5819 | static int trace_die_handler(struct notifier_block *self, | |
5820 | unsigned long val, | |
5821 | void *data) | |
5822 | { | |
5823 | switch (val) { | |
5824 | case DIE_OOPS: | |
944ac425 | 5825 | if (ftrace_dump_on_oops) |
cecbca96 | 5826 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
5827 | break; |
5828 | default: | |
5829 | break; | |
5830 | } | |
5831 | return NOTIFY_OK; | |
5832 | } | |
5833 | ||
5834 | static struct notifier_block trace_die_notifier = { | |
5835 | .notifier_call = trace_die_handler, | |
5836 | .priority = 200 | |
5837 | }; | |
5838 | ||
5839 | /* | |
5840 | * printk is set to max of 1024, we really don't need it that big. | |
5841 | * Nothing should be printing 1000 characters anyway. | |
5842 | */ | |
5843 | #define TRACE_MAX_PRINT 1000 | |
5844 | ||
5845 | /* | |
5846 | * Define here KERN_TRACE so that we have one place to modify | |
5847 | * it if we decide to change what log level the ftrace dump | |
5848 | * should be at. | |
5849 | */ | |
428aee14 | 5850 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 5851 | |
955b61e5 | 5852 | void |
3f5a54e3 SR |
5853 | trace_printk_seq(struct trace_seq *s) |
5854 | { | |
5855 | /* Probably should print a warning here. */ | |
5856 | if (s->len >= 1000) | |
5857 | s->len = 1000; | |
5858 | ||
5859 | /* should be zero ended, but we are paranoid. */ | |
5860 | s->buffer[s->len] = 0; | |
5861 | ||
5862 | printk(KERN_TRACE "%s", s->buffer); | |
5863 | ||
f9520750 | 5864 | trace_seq_init(s); |
3f5a54e3 SR |
5865 | } |
5866 | ||
955b61e5 JW |
5867 | void trace_init_global_iter(struct trace_iterator *iter) |
5868 | { | |
5869 | iter->tr = &global_trace; | |
2b6080f2 | 5870 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 5871 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 5872 | iter->trace_buffer = &global_trace.trace_buffer; |
955b61e5 JW |
5873 | } |
5874 | ||
cecbca96 FW |
5875 | static void |
5876 | __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode) | |
3f5a54e3 | 5877 | { |
445c8951 | 5878 | static arch_spinlock_t ftrace_dump_lock = |
edc35bd7 | 5879 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
3f5a54e3 SR |
5880 | /* use static because iter can be a bit big for the stack */ |
5881 | static struct trace_iterator iter; | |
cf586b61 | 5882 | unsigned int old_userobj; |
3f5a54e3 | 5883 | static int dump_ran; |
d769041f SR |
5884 | unsigned long flags; |
5885 | int cnt = 0, cpu; | |
3f5a54e3 SR |
5886 | |
5887 | /* only one dump */ | |
cd891ae0 | 5888 | local_irq_save(flags); |
0199c4e6 | 5889 | arch_spin_lock(&ftrace_dump_lock); |
3f5a54e3 SR |
5890 | if (dump_ran) |
5891 | goto out; | |
5892 | ||
5893 | dump_ran = 1; | |
5894 | ||
0ee6b6cf | 5895 | tracing_off(); |
cf586b61 | 5896 | |
e0a413f6 SR |
5897 | /* Did function tracer already get disabled? */ |
5898 | if (ftrace_is_dead()) { | |
5899 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
5900 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
5901 | } | |
5902 | ||
cf586b61 FW |
5903 | if (disable_tracing) |
5904 | ftrace_kill(); | |
3f5a54e3 | 5905 | |
38dbe0b1 | 5906 | /* Simulate the iterator */ |
955b61e5 JW |
5907 | trace_init_global_iter(&iter); |
5908 | ||
d769041f | 5909 | for_each_tracing_cpu(cpu) { |
12883efb | 5910 | atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled); |
d769041f SR |
5911 | } |
5912 | ||
cf586b61 FW |
5913 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
5914 | ||
b54d3de9 TE |
5915 | /* don't look at user memory in panic mode */ |
5916 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
5917 | ||
cecbca96 FW |
5918 | switch (oops_dump_mode) { |
5919 | case DUMP_ALL: | |
ae3b5093 | 5920 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
5921 | break; |
5922 | case DUMP_ORIG: | |
5923 | iter.cpu_file = raw_smp_processor_id(); | |
5924 | break; | |
5925 | case DUMP_NONE: | |
5926 | goto out_enable; | |
5927 | default: | |
5928 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 5929 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
5930 | } |
5931 | ||
5932 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 SR |
5933 | |
5934 | /* | |
5935 | * We need to stop all tracing on all CPUS to read the | |
5936 | * the next buffer. This is a bit expensive, but is | |
5937 | * not done often. We fill all what we can read, | |
5938 | * and then release the locks again. | |
5939 | */ | |
5940 | ||
3f5a54e3 SR |
5941 | while (!trace_empty(&iter)) { |
5942 | ||
5943 | if (!cnt) | |
5944 | printk(KERN_TRACE "---------------------------------\n"); | |
5945 | ||
5946 | cnt++; | |
5947 | ||
5948 | /* reset all but tr, trace, and overruns */ | |
5949 | memset(&iter.seq, 0, | |
5950 | sizeof(struct trace_iterator) - | |
5951 | offsetof(struct trace_iterator, seq)); | |
5952 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
5953 | iter.pos = -1; | |
5954 | ||
955b61e5 | 5955 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
5956 | int ret; |
5957 | ||
5958 | ret = print_trace_line(&iter); | |
5959 | if (ret != TRACE_TYPE_NO_CONSUME) | |
5960 | trace_consume(&iter); | |
3f5a54e3 | 5961 | } |
b892e5c8 | 5962 | touch_nmi_watchdog(); |
3f5a54e3 SR |
5963 | |
5964 | trace_printk_seq(&iter.seq); | |
5965 | } | |
5966 | ||
5967 | if (!cnt) | |
5968 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
5969 | else | |
5970 | printk(KERN_TRACE "---------------------------------\n"); | |
5971 | ||
cecbca96 | 5972 | out_enable: |
cf586b61 FW |
5973 | /* Re-enable tracing if requested */ |
5974 | if (!disable_tracing) { | |
5975 | trace_flags |= old_userobj; | |
5976 | ||
5977 | for_each_tracing_cpu(cpu) { | |
12883efb | 5978 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); |
cf586b61 FW |
5979 | } |
5980 | tracing_on(); | |
5981 | } | |
5982 | ||
3f5a54e3 | 5983 | out: |
0199c4e6 | 5984 | arch_spin_unlock(&ftrace_dump_lock); |
cd891ae0 | 5985 | local_irq_restore(flags); |
3f5a54e3 SR |
5986 | } |
5987 | ||
cf586b61 | 5988 | /* By default: disable tracing after the dump */ |
cecbca96 | 5989 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
cf586b61 | 5990 | { |
cecbca96 | 5991 | __ftrace_dump(true, oops_dump_mode); |
cf586b61 | 5992 | } |
a8eecf22 | 5993 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 5994 | |
3928a8a2 | 5995 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 5996 | { |
73c5162a | 5997 | int ring_buf_size; |
9e01c1b7 | 5998 | int ret = -ENOMEM; |
4c11d7ae | 5999 | |
750912fa | 6000 | |
9e01c1b7 RR |
6001 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
6002 | goto out; | |
6003 | ||
6004 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
6005 | goto out_free_buffer_mask; | |
4c11d7ae | 6006 | |
07d777fe SR |
6007 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
6008 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 6009 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
6010 | trace_printk_init_buffers(); |
6011 | ||
73c5162a SR |
6012 | /* To save memory, keep the ring buffer size to its minimum */ |
6013 | if (ring_buffer_expanded) | |
6014 | ring_buf_size = trace_buf_size; | |
6015 | else | |
6016 | ring_buf_size = 1; | |
6017 | ||
9e01c1b7 RR |
6018 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
6019 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
6020 | ||
2b6080f2 SR |
6021 | raw_spin_lock_init(&global_trace.start_lock); |
6022 | ||
9e01c1b7 | 6023 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 6024 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
6025 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
6026 | WARN_ON(1); | |
9e01c1b7 | 6027 | goto out_free_cpumask; |
4c11d7ae | 6028 | } |
a7603ff4 | 6029 | |
499e5470 SR |
6030 | if (global_trace.buffer_disabled) |
6031 | tracing_off(); | |
4c11d7ae | 6032 | |
bc0c38d1 SR |
6033 | trace_init_cmdlines(); |
6034 | ||
43a15386 | 6035 | register_tracer(&nop_trace); |
d840f718 | 6036 | |
2b6080f2 SR |
6037 | global_trace.current_trace = &nop_trace; |
6038 | ||
60a11774 SR |
6039 | /* All seems OK, enable tracing */ |
6040 | tracing_disabled = 0; | |
3928a8a2 | 6041 | |
3f5a54e3 SR |
6042 | atomic_notifier_chain_register(&panic_notifier_list, |
6043 | &trace_panic_notifier); | |
6044 | ||
6045 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 6046 | |
ae63b31e SR |
6047 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
6048 | ||
2b6080f2 SR |
6049 | /* Holder for file callbacks */ |
6050 | global_trace.trace_cpu.cpu = RING_BUFFER_ALL_CPUS; | |
6051 | global_trace.trace_cpu.tr = &global_trace; | |
6052 | ||
ae63b31e SR |
6053 | INIT_LIST_HEAD(&global_trace.systems); |
6054 | INIT_LIST_HEAD(&global_trace.events); | |
6055 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
6056 | ||
7bcfaf54 SR |
6057 | while (trace_boot_options) { |
6058 | char *option; | |
6059 | ||
6060 | option = strsep(&trace_boot_options, ","); | |
2b6080f2 | 6061 | trace_set_options(&global_trace, option); |
7bcfaf54 SR |
6062 | } |
6063 | ||
2fc1dfbe | 6064 | return 0; |
3f5a54e3 | 6065 | |
9e01c1b7 | 6066 | out_free_cpumask: |
12883efb SRRH |
6067 | free_percpu(global_trace.trace_buffer.data); |
6068 | #ifdef CONFIG_TRACER_MAX_TRACE | |
6069 | free_percpu(global_trace.max_buffer.data); | |
6070 | #endif | |
9e01c1b7 RR |
6071 | free_cpumask_var(tracing_cpumask); |
6072 | out_free_buffer_mask: | |
6073 | free_cpumask_var(tracing_buffer_mask); | |
6074 | out: | |
6075 | return ret; | |
bc0c38d1 | 6076 | } |
b2821ae6 SR |
6077 | |
6078 | __init static int clear_boot_tracer(void) | |
6079 | { | |
6080 | /* | |
6081 | * The default tracer at boot buffer is an init section. | |
6082 | * This function is called in lateinit. If we did not | |
6083 | * find the boot tracer, then clear it out, to prevent | |
6084 | * later registration from accessing the buffer that is | |
6085 | * about to be freed. | |
6086 | */ | |
6087 | if (!default_bootup_tracer) | |
6088 | return 0; | |
6089 | ||
6090 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
6091 | default_bootup_tracer); | |
6092 | default_bootup_tracer = NULL; | |
6093 | ||
6094 | return 0; | |
6095 | } | |
6096 | ||
b5ad384e FW |
6097 | early_initcall(tracer_alloc_buffers); |
6098 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 6099 | late_initcall(clear_boot_tracer); |