Commit | Line | Data |
---|---|---|
bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
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 | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
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> |
bc0c38d1 | 39 | #include <linux/fs.h> |
86387f7e | 40 | |
bc0c38d1 | 41 | #include "trace.h" |
f0868d1e | 42 | #include "trace_output.h" |
bc0c38d1 | 43 | |
73c5162a SR |
44 | /* |
45 | * On boot up, the ring buffer is set to the minimum size, so that | |
46 | * we do not waste memory on systems that are not using tracing. | |
47 | */ | |
020e5f85 | 48 | int ring_buffer_expanded; |
73c5162a | 49 | |
8e1b82e0 FW |
50 | /* |
51 | * We need to change this state when a selftest is running. | |
ff32504f FW |
52 | * A selftest will lurk into the ring-buffer to count the |
53 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 54 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
55 | * at the same time, giving false positive or negative results. |
56 | */ | |
8e1b82e0 | 57 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 58 | |
b2821ae6 SR |
59 | /* |
60 | * If a tracer is running, we do not want to run SELFTEST. | |
61 | */ | |
020e5f85 | 62 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 63 | |
adf9f195 FW |
64 | /* For tracers that don't implement custom flags */ |
65 | static struct tracer_opt dummy_tracer_opt[] = { | |
66 | { } | |
67 | }; | |
68 | ||
69 | static struct tracer_flags dummy_tracer_flags = { | |
70 | .val = 0, | |
71 | .opts = dummy_tracer_opt | |
72 | }; | |
73 | ||
74 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
75 | { | |
76 | return 0; | |
77 | } | |
0f048701 SR |
78 | |
79 | /* | |
80 | * Kill all tracing for good (never come back). | |
81 | * It is initialized to 1 but will turn to zero if the initialization | |
82 | * of the tracer is successful. But that is the only place that sets | |
83 | * this back to zero. | |
84 | */ | |
4fd27358 | 85 | static int tracing_disabled = 1; |
0f048701 | 86 | |
9288f99a | 87 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f SR |
88 | |
89 | static inline void ftrace_disable_cpu(void) | |
90 | { | |
91 | preempt_disable(); | |
dd17c8f7 | 92 | __this_cpu_inc(ftrace_cpu_disabled); |
d769041f SR |
93 | } |
94 | ||
95 | static inline void ftrace_enable_cpu(void) | |
96 | { | |
dd17c8f7 | 97 | __this_cpu_dec(ftrace_cpu_disabled); |
d769041f SR |
98 | preempt_enable(); |
99 | } | |
100 | ||
955b61e5 | 101 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 102 | |
944ac425 SR |
103 | /* |
104 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
105 | * | |
106 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
107 | * is set, then ftrace_dump is called. This will output the contents | |
108 | * of the ftrace buffers to the console. This is very useful for | |
109 | * capturing traces that lead to crashes and outputing it to a | |
110 | * serial console. | |
111 | * | |
112 | * It is default off, but you can enable it with either specifying | |
113 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
114 | * /proc/sys/kernel/ftrace_dump_on_oops |
115 | * Set 1 if you want to dump buffers of all CPUs | |
116 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 117 | */ |
cecbca96 FW |
118 | |
119 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 120 | |
b2821ae6 SR |
121 | static int tracing_set_tracer(const char *buf); |
122 | ||
ee6c2c1b LZ |
123 | #define MAX_TRACER_SIZE 100 |
124 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 125 | static char *default_bootup_tracer; |
d9e54076 | 126 | |
1beee96b | 127 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 128 | { |
ee6c2c1b | 129 | strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 130 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a SR |
131 | /* We are using ftrace early, expand it */ |
132 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
133 | return 1; |
134 | } | |
1beee96b | 135 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 136 | |
944ac425 SR |
137 | static int __init set_ftrace_dump_on_oops(char *str) |
138 | { | |
cecbca96 FW |
139 | if (*str++ != '=' || !*str) { |
140 | ftrace_dump_on_oops = DUMP_ALL; | |
141 | return 1; | |
142 | } | |
143 | ||
144 | if (!strcmp("orig_cpu", str)) { | |
145 | ftrace_dump_on_oops = DUMP_ORIG; | |
146 | return 1; | |
147 | } | |
148 | ||
149 | return 0; | |
944ac425 SR |
150 | } |
151 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 152 | |
cf8e3474 | 153 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
154 | { |
155 | nsec += 500; | |
156 | do_div(nsec, 1000); | |
157 | return nsec; | |
158 | } | |
159 | ||
4fcdae83 SR |
160 | /* |
161 | * The global_trace is the descriptor that holds the tracing | |
162 | * buffers for the live tracing. For each CPU, it contains | |
163 | * a link list of pages that will store trace entries. The | |
164 | * page descriptor of the pages in the memory is used to hold | |
165 | * the link list by linking the lru item in the page descriptor | |
166 | * to each of the pages in the buffer per CPU. | |
167 | * | |
168 | * For each active CPU there is a data field that holds the | |
169 | * pages for the buffer for that CPU. Each CPU has the same number | |
170 | * of pages allocated for its buffer. | |
171 | */ | |
bc0c38d1 SR |
172 | static struct trace_array global_trace; |
173 | ||
174 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
175 | ||
e77405ad SR |
176 | int filter_current_check_discard(struct ring_buffer *buffer, |
177 | struct ftrace_event_call *call, void *rec, | |
eb02ce01 TZ |
178 | struct ring_buffer_event *event) |
179 | { | |
e77405ad | 180 | return filter_check_discard(call, rec, buffer, event); |
eb02ce01 | 181 | } |
17c873ec | 182 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 183 | |
37886f6a SR |
184 | cycle_t ftrace_now(int cpu) |
185 | { | |
186 | u64 ts; | |
187 | ||
188 | /* Early boot up does not have a buffer yet */ | |
189 | if (!global_trace.buffer) | |
190 | return trace_clock_local(); | |
191 | ||
192 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
193 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
194 | ||
195 | return ts; | |
196 | } | |
bc0c38d1 | 197 | |
4fcdae83 SR |
198 | /* |
199 | * The max_tr is used to snapshot the global_trace when a maximum | |
200 | * latency is reached. Some tracers will use this to store a maximum | |
201 | * trace while it continues examining live traces. | |
202 | * | |
203 | * The buffers for the max_tr are set up the same as the global_trace. | |
204 | * When a snapshot is taken, the link list of the max_tr is swapped | |
205 | * with the link list of the global_trace and the buffers are reset for | |
206 | * the global_trace so the tracing can continue. | |
207 | */ | |
bc0c38d1 SR |
208 | static struct trace_array max_tr; |
209 | ||
9705f69e | 210 | static DEFINE_PER_CPU(struct trace_array_cpu, max_tr_data); |
bc0c38d1 | 211 | |
4fcdae83 | 212 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 213 | static int tracer_enabled = 1; |
4fcdae83 | 214 | |
9036990d SR |
215 | /** |
216 | * tracing_is_enabled - return tracer_enabled status | |
217 | * | |
218 | * This function is used by other tracers to know the status | |
219 | * of the tracer_enabled flag. Tracers may use this function | |
220 | * to know if it should enable their features when starting | |
221 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
222 | */ | |
223 | int tracing_is_enabled(void) | |
224 | { | |
225 | return tracer_enabled; | |
226 | } | |
227 | ||
4fcdae83 | 228 | /* |
3928a8a2 SR |
229 | * trace_buf_size is the size in bytes that is allocated |
230 | * for a buffer. Note, the number of bytes is always rounded | |
231 | * to page size. | |
3f5a54e3 SR |
232 | * |
233 | * This number is purposely set to a low number of 16384. | |
234 | * If the dump on oops happens, it will be much appreciated | |
235 | * to not have to wait for all that output. Anyway this can be | |
236 | * boot time and run time configurable. | |
4fcdae83 | 237 | */ |
3928a8a2 | 238 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 239 | |
3928a8a2 | 240 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 241 | |
4fcdae83 | 242 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 243 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
244 | |
245 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 246 | static struct tracer *current_trace __read_mostly; |
4fcdae83 | 247 | |
4fcdae83 SR |
248 | /* |
249 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 250 | */ |
bc0c38d1 | 251 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 252 | |
7e53bd42 LJ |
253 | /* |
254 | * serialize the access of the ring buffer | |
255 | * | |
256 | * ring buffer serializes readers, but it is low level protection. | |
257 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
258 | * are not protected by ring buffer. | |
259 | * | |
260 | * The content of events may become garbage if we allow other process consumes | |
261 | * these events concurrently: | |
262 | * A) the page of the consumed events may become a normal page | |
263 | * (not reader page) in ring buffer, and this page will be rewrited | |
264 | * by events producer. | |
265 | * B) The page of the consumed events may become a page for splice_read, | |
266 | * and this page will be returned to system. | |
267 | * | |
268 | * These primitives allow multi process access to different cpu ring buffer | |
269 | * concurrently. | |
270 | * | |
271 | * These primitives don't distinguish read-only and read-consume access. | |
272 | * Multi read-only access are also serialized. | |
273 | */ | |
274 | ||
275 | #ifdef CONFIG_SMP | |
276 | static DECLARE_RWSEM(all_cpu_access_lock); | |
277 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
278 | ||
279 | static inline void trace_access_lock(int cpu) | |
280 | { | |
281 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
282 | /* gain it for accessing the whole ring buffer. */ | |
283 | down_write(&all_cpu_access_lock); | |
284 | } else { | |
285 | /* gain it for accessing a cpu ring buffer. */ | |
286 | ||
287 | /* Firstly block other trace_access_lock(TRACE_PIPE_ALL_CPU). */ | |
288 | down_read(&all_cpu_access_lock); | |
289 | ||
290 | /* Secondly block other access to this @cpu ring buffer. */ | |
291 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
292 | } | |
293 | } | |
294 | ||
295 | static inline void trace_access_unlock(int cpu) | |
296 | { | |
297 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
298 | up_write(&all_cpu_access_lock); | |
299 | } else { | |
300 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
301 | up_read(&all_cpu_access_lock); | |
302 | } | |
303 | } | |
304 | ||
305 | static inline void trace_access_lock_init(void) | |
306 | { | |
307 | int cpu; | |
308 | ||
309 | for_each_possible_cpu(cpu) | |
310 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
311 | } | |
312 | ||
313 | #else | |
314 | ||
315 | static DEFINE_MUTEX(access_lock); | |
316 | ||
317 | static inline void trace_access_lock(int cpu) | |
318 | { | |
319 | (void)cpu; | |
320 | mutex_lock(&access_lock); | |
321 | } | |
322 | ||
323 | static inline void trace_access_unlock(int cpu) | |
324 | { | |
325 | (void)cpu; | |
326 | mutex_unlock(&access_lock); | |
327 | } | |
328 | ||
329 | static inline void trace_access_lock_init(void) | |
330 | { | |
331 | } | |
332 | ||
333 | #endif | |
334 | ||
4fcdae83 | 335 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ |
4e655519 IM |
336 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
337 | ||
ee6bce52 | 338 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 339 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 340 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
750912fa | 341 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE; |
4e655519 | 342 | |
b8de7bd1 SR |
343 | static int trace_stop_count; |
344 | static DEFINE_SPINLOCK(tracing_start_lock); | |
345 | ||
4fcdae83 SR |
346 | /** |
347 | * trace_wake_up - wake up tasks waiting for trace input | |
348 | * | |
349 | * Simply wakes up any task that is blocked on the trace_wait | |
350 | * queue. These is used with trace_poll for tasks polling the trace. | |
351 | */ | |
4e655519 IM |
352 | void trace_wake_up(void) |
353 | { | |
89f19f04 AM |
354 | int cpu; |
355 | ||
356 | if (trace_flags & TRACE_ITER_BLOCK) | |
357 | return; | |
017730c1 IM |
358 | /* |
359 | * The runqueue_is_locked() can fail, but this is the best we | |
360 | * have for now: | |
361 | */ | |
89f19f04 AM |
362 | cpu = get_cpu(); |
363 | if (!runqueue_is_locked(cpu)) | |
4e655519 | 364 | wake_up(&trace_wait); |
89f19f04 | 365 | put_cpu(); |
4e655519 | 366 | } |
bc0c38d1 | 367 | |
3928a8a2 | 368 | static int __init set_buf_size(char *str) |
bc0c38d1 | 369 | { |
3928a8a2 | 370 | unsigned long buf_size; |
c6caeeb1 | 371 | |
bc0c38d1 SR |
372 | if (!str) |
373 | return 0; | |
9d612bef | 374 | buf_size = memparse(str, &str); |
c6caeeb1 | 375 | /* nr_entries can not be zero */ |
9d612bef | 376 | if (buf_size == 0) |
c6caeeb1 | 377 | return 0; |
3928a8a2 | 378 | trace_buf_size = buf_size; |
bc0c38d1 SR |
379 | return 1; |
380 | } | |
3928a8a2 | 381 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 382 | |
0e950173 TB |
383 | static int __init set_tracing_thresh(char *str) |
384 | { | |
385 | unsigned long threshhold; | |
386 | int ret; | |
387 | ||
388 | if (!str) | |
389 | return 0; | |
390 | ret = strict_strtoul(str, 0, &threshhold); | |
391 | if (ret < 0) | |
392 | return 0; | |
393 | tracing_thresh = threshhold * 1000; | |
394 | return 1; | |
395 | } | |
396 | __setup("tracing_thresh=", set_tracing_thresh); | |
397 | ||
57f50be1 SR |
398 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
399 | { | |
400 | return nsecs / 1000; | |
401 | } | |
402 | ||
4fcdae83 | 403 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
404 | static const char *trace_options[] = { |
405 | "print-parent", | |
406 | "sym-offset", | |
407 | "sym-addr", | |
408 | "verbose", | |
f9896bf3 | 409 | "raw", |
5e3ca0ec | 410 | "hex", |
cb0f12aa | 411 | "bin", |
2a2cc8f7 | 412 | "block", |
86387f7e | 413 | "stacktrace", |
5e1607a0 | 414 | "trace_printk", |
b2a866f9 | 415 | "ftrace_preempt", |
9f029e83 | 416 | "branch", |
12ef7d44 | 417 | "annotate", |
02b67518 | 418 | "userstacktrace", |
b54d3de9 | 419 | "sym-userobj", |
66896a85 | 420 | "printk-msg-only", |
c4a8e8be | 421 | "context-info", |
c032ef64 | 422 | "latency-format", |
be6f164a | 423 | "sleep-time", |
a2a16d6a | 424 | "graph-time", |
e870e9a1 | 425 | "record-cmd", |
750912fa | 426 | "overwrite", |
bc0c38d1 SR |
427 | NULL |
428 | }; | |
429 | ||
5079f326 Z |
430 | static struct { |
431 | u64 (*func)(void); | |
432 | const char *name; | |
433 | } trace_clocks[] = { | |
434 | { trace_clock_local, "local" }, | |
435 | { trace_clock_global, "global" }, | |
436 | }; | |
437 | ||
438 | int trace_clock_id; | |
439 | ||
b63f39ea | 440 | /* |
441 | * trace_parser_get_init - gets the buffer for trace parser | |
442 | */ | |
443 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
444 | { | |
445 | memset(parser, 0, sizeof(*parser)); | |
446 | ||
447 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
448 | if (!parser->buffer) | |
449 | return 1; | |
450 | ||
451 | parser->size = size; | |
452 | return 0; | |
453 | } | |
454 | ||
455 | /* | |
456 | * trace_parser_put - frees the buffer for trace parser | |
457 | */ | |
458 | void trace_parser_put(struct trace_parser *parser) | |
459 | { | |
460 | kfree(parser->buffer); | |
461 | } | |
462 | ||
463 | /* | |
464 | * trace_get_user - reads the user input string separated by space | |
465 | * (matched by isspace(ch)) | |
466 | * | |
467 | * For each string found the 'struct trace_parser' is updated, | |
468 | * and the function returns. | |
469 | * | |
470 | * Returns number of bytes read. | |
471 | * | |
472 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
473 | */ | |
474 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
475 | size_t cnt, loff_t *ppos) | |
476 | { | |
477 | char ch; | |
478 | size_t read = 0; | |
479 | ssize_t ret; | |
480 | ||
481 | if (!*ppos) | |
482 | trace_parser_clear(parser); | |
483 | ||
484 | ret = get_user(ch, ubuf++); | |
485 | if (ret) | |
486 | goto out; | |
487 | ||
488 | read++; | |
489 | cnt--; | |
490 | ||
491 | /* | |
492 | * The parser is not finished with the last write, | |
493 | * continue reading the user input without skipping spaces. | |
494 | */ | |
495 | if (!parser->cont) { | |
496 | /* skip white space */ | |
497 | while (cnt && isspace(ch)) { | |
498 | ret = get_user(ch, ubuf++); | |
499 | if (ret) | |
500 | goto out; | |
501 | read++; | |
502 | cnt--; | |
503 | } | |
504 | ||
505 | /* only spaces were written */ | |
506 | if (isspace(ch)) { | |
507 | *ppos += read; | |
508 | ret = read; | |
509 | goto out; | |
510 | } | |
511 | ||
512 | parser->idx = 0; | |
513 | } | |
514 | ||
515 | /* read the non-space input */ | |
516 | while (cnt && !isspace(ch)) { | |
3c235a33 | 517 | if (parser->idx < parser->size - 1) |
b63f39ea | 518 | parser->buffer[parser->idx++] = ch; |
519 | else { | |
520 | ret = -EINVAL; | |
521 | goto out; | |
522 | } | |
523 | ret = get_user(ch, ubuf++); | |
524 | if (ret) | |
525 | goto out; | |
526 | read++; | |
527 | cnt--; | |
528 | } | |
529 | ||
530 | /* We either got finished input or we have to wait for another call. */ | |
531 | if (isspace(ch)) { | |
532 | parser->buffer[parser->idx] = 0; | |
533 | parser->cont = false; | |
534 | } else { | |
535 | parser->cont = true; | |
536 | parser->buffer[parser->idx++] = ch; | |
537 | } | |
538 | ||
539 | *ppos += read; | |
540 | ret = read; | |
541 | ||
542 | out: | |
543 | return ret; | |
544 | } | |
545 | ||
6c6c2796 PP |
546 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
547 | { | |
548 | int len; | |
549 | int ret; | |
550 | ||
2dc5d12b SR |
551 | if (!cnt) |
552 | return 0; | |
553 | ||
6c6c2796 PP |
554 | if (s->len <= s->readpos) |
555 | return -EBUSY; | |
556 | ||
557 | len = s->len - s->readpos; | |
558 | if (cnt > len) | |
559 | cnt = len; | |
560 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 561 | if (ret == cnt) |
6c6c2796 PP |
562 | return -EFAULT; |
563 | ||
2dc5d12b SR |
564 | cnt -= ret; |
565 | ||
e74da523 | 566 | s->readpos += cnt; |
6c6c2796 | 567 | return cnt; |
214023c3 SR |
568 | } |
569 | ||
b8b94265 | 570 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
571 | { |
572 | int len; | |
573 | void *ret; | |
574 | ||
575 | if (s->len <= s->readpos) | |
576 | return -EBUSY; | |
577 | ||
578 | len = s->len - s->readpos; | |
579 | if (cnt > len) | |
580 | cnt = len; | |
581 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
582 | if (!ret) | |
583 | return -EFAULT; | |
584 | ||
e74da523 | 585 | s->readpos += cnt; |
3c56819b EGM |
586 | return cnt; |
587 | } | |
588 | ||
5d4a9dba SR |
589 | /* |
590 | * ftrace_max_lock is used to protect the swapping of buffers | |
591 | * when taking a max snapshot. The buffers themselves are | |
592 | * protected by per_cpu spinlocks. But the action of the swap | |
593 | * needs its own lock. | |
594 | * | |
445c8951 | 595 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
596 | * with performance when lockdep debugging is enabled. |
597 | * | |
598 | * It is also used in other places outside the update_max_tr | |
599 | * so it needs to be defined outside of the | |
600 | * CONFIG_TRACER_MAX_TRACE. | |
601 | */ | |
445c8951 | 602 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 603 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba | 604 | |
0e950173 TB |
605 | unsigned long __read_mostly tracing_thresh; |
606 | ||
5d4a9dba SR |
607 | #ifdef CONFIG_TRACER_MAX_TRACE |
608 | unsigned long __read_mostly tracing_max_latency; | |
5d4a9dba SR |
609 | |
610 | /* | |
611 | * Copy the new maximum trace into the separate maximum-trace | |
612 | * structure. (this way the maximum trace is permanently saved, | |
613 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
614 | */ | |
615 | static void | |
616 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
617 | { | |
618 | struct trace_array_cpu *data = tr->data[cpu]; | |
1acaa1b2 | 619 | struct trace_array_cpu *max_data; |
5d4a9dba SR |
620 | |
621 | max_tr.cpu = cpu; | |
622 | max_tr.time_start = data->preempt_timestamp; | |
623 | ||
8248ac05 SR |
624 | max_data = max_tr.data[cpu]; |
625 | max_data->saved_latency = tracing_max_latency; | |
626 | max_data->critical_start = data->critical_start; | |
627 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 628 | |
1acaa1b2 | 629 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 SR |
630 | max_data->pid = tsk->pid; |
631 | max_data->uid = task_uid(tsk); | |
632 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
633 | max_data->policy = tsk->policy; | |
634 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
635 | |
636 | /* record this tasks comm */ | |
637 | tracing_record_cmdline(tsk); | |
638 | } | |
639 | ||
4fcdae83 SR |
640 | /** |
641 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
642 | * @tr: tracer | |
643 | * @tsk: the task with the latency | |
644 | * @cpu: The cpu that initiated the trace. | |
645 | * | |
646 | * Flip the buffers between the @tr and the max_tr and record information | |
647 | * about which task was the cause of this latency. | |
648 | */ | |
e309b41d | 649 | void |
bc0c38d1 SR |
650 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
651 | { | |
3928a8a2 | 652 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 653 | |
b8de7bd1 SR |
654 | if (trace_stop_count) |
655 | return; | |
656 | ||
4c11d7ae | 657 | WARN_ON_ONCE(!irqs_disabled()); |
ef710e10 KM |
658 | if (!current_trace->use_max_tr) { |
659 | WARN_ON_ONCE(1); | |
660 | return; | |
661 | } | |
0199c4e6 | 662 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
663 | |
664 | tr->buffer = max_tr.buffer; | |
665 | max_tr.buffer = buf; | |
666 | ||
bc0c38d1 | 667 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 668 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
669 | } |
670 | ||
671 | /** | |
672 | * update_max_tr_single - only copy one trace over, and reset the rest | |
673 | * @tr - tracer | |
674 | * @tsk - task with the latency | |
675 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
676 | * |
677 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 678 | */ |
e309b41d | 679 | void |
bc0c38d1 SR |
680 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
681 | { | |
3928a8a2 | 682 | int ret; |
bc0c38d1 | 683 | |
b8de7bd1 SR |
684 | if (trace_stop_count) |
685 | return; | |
686 | ||
4c11d7ae | 687 | WARN_ON_ONCE(!irqs_disabled()); |
ef710e10 KM |
688 | if (!current_trace->use_max_tr) { |
689 | WARN_ON_ONCE(1); | |
690 | return; | |
691 | } | |
692 | ||
0199c4e6 | 693 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 694 | |
d769041f SR |
695 | ftrace_disable_cpu(); |
696 | ||
3928a8a2 SR |
697 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); |
698 | ||
e8165dbb SR |
699 | if (ret == -EBUSY) { |
700 | /* | |
701 | * We failed to swap the buffer due to a commit taking | |
702 | * place on this CPU. We fail to record, but we reset | |
703 | * the max trace buffer (no one writes directly to it) | |
704 | * and flag that it failed. | |
705 | */ | |
706 | trace_array_printk(&max_tr, _THIS_IP_, | |
707 | "Failed to swap buffers due to commit in progress\n"); | |
708 | } | |
709 | ||
d769041f SR |
710 | ftrace_enable_cpu(); |
711 | ||
e8165dbb | 712 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
713 | |
714 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 715 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 716 | } |
5d4a9dba | 717 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 718 | |
4fcdae83 SR |
719 | /** |
720 | * register_tracer - register a tracer with the ftrace system. | |
721 | * @type - the plugin for the tracer | |
722 | * | |
723 | * Register a new plugin tracer. | |
724 | */ | |
bc0c38d1 | 725 | int register_tracer(struct tracer *type) |
e7669b8e HE |
726 | __releases(kernel_lock) |
727 | __acquires(kernel_lock) | |
bc0c38d1 SR |
728 | { |
729 | struct tracer *t; | |
bc0c38d1 SR |
730 | int ret = 0; |
731 | ||
732 | if (!type->name) { | |
733 | pr_info("Tracer must have a name\n"); | |
734 | return -1; | |
735 | } | |
736 | ||
24a461d5 | 737 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
738 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
739 | return -1; | |
740 | } | |
741 | ||
bc0c38d1 | 742 | mutex_lock(&trace_types_lock); |
86fa2f60 | 743 | |
8e1b82e0 FW |
744 | tracing_selftest_running = true; |
745 | ||
bc0c38d1 SR |
746 | for (t = trace_types; t; t = t->next) { |
747 | if (strcmp(type->name, t->name) == 0) { | |
748 | /* already found */ | |
ee6c2c1b | 749 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
750 | type->name); |
751 | ret = -1; | |
752 | goto out; | |
753 | } | |
754 | } | |
755 | ||
adf9f195 FW |
756 | if (!type->set_flag) |
757 | type->set_flag = &dummy_set_flag; | |
758 | if (!type->flags) | |
759 | type->flags = &dummy_tracer_flags; | |
760 | else | |
761 | if (!type->flags->opts) | |
762 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
763 | if (!type->wait_pipe) |
764 | type->wait_pipe = default_wait_pipe; | |
765 | ||
adf9f195 | 766 | |
60a11774 | 767 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 768 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 769 | struct tracer *saved_tracer = current_trace; |
60a11774 | 770 | struct trace_array *tr = &global_trace; |
ff32504f | 771 | |
60a11774 SR |
772 | /* |
773 | * Run a selftest on this tracer. | |
774 | * Here we reset the trace buffer, and set the current | |
775 | * tracer to be this tracer. The tracer can then run some | |
776 | * internal tracing to verify that everything is in order. | |
777 | * If we fail, we do not register this tracer. | |
778 | */ | |
76f0d073 | 779 | tracing_reset_online_cpus(tr); |
86fa2f60 | 780 | |
60a11774 | 781 | current_trace = type; |
60a11774 SR |
782 | /* the test is responsible for initializing and enabling */ |
783 | pr_info("Testing tracer %s: ", type->name); | |
784 | ret = type->selftest(type, tr); | |
785 | /* the test is responsible for resetting too */ | |
786 | current_trace = saved_tracer; | |
60a11774 SR |
787 | if (ret) { |
788 | printk(KERN_CONT "FAILED!\n"); | |
789 | goto out; | |
790 | } | |
1d4db00a | 791 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 792 | tracing_reset_online_cpus(tr); |
86fa2f60 | 793 | |
60a11774 SR |
794 | printk(KERN_CONT "PASSED\n"); |
795 | } | |
796 | #endif | |
797 | ||
bc0c38d1 SR |
798 | type->next = trace_types; |
799 | trace_types = type; | |
60a11774 | 800 | |
bc0c38d1 | 801 | out: |
8e1b82e0 | 802 | tracing_selftest_running = false; |
bc0c38d1 SR |
803 | mutex_unlock(&trace_types_lock); |
804 | ||
dac74940 SR |
805 | if (ret || !default_bootup_tracer) |
806 | goto out_unlock; | |
807 | ||
ee6c2c1b | 808 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
809 | goto out_unlock; |
810 | ||
811 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
812 | /* Do we want this tracer to start on bootup? */ | |
813 | tracing_set_tracer(type->name); | |
814 | default_bootup_tracer = NULL; | |
815 | /* disable other selftests, since this will break it. */ | |
816 | tracing_selftest_disabled = 1; | |
b2821ae6 | 817 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
818 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
819 | type->name); | |
b2821ae6 | 820 | #endif |
b2821ae6 | 821 | |
dac74940 | 822 | out_unlock: |
bc0c38d1 SR |
823 | return ret; |
824 | } | |
825 | ||
826 | void unregister_tracer(struct tracer *type) | |
827 | { | |
828 | struct tracer **t; | |
bc0c38d1 SR |
829 | |
830 | mutex_lock(&trace_types_lock); | |
831 | for (t = &trace_types; *t; t = &(*t)->next) { | |
832 | if (*t == type) | |
833 | goto found; | |
834 | } | |
ee6c2c1b | 835 | pr_info("Tracer %s not registered\n", type->name); |
bc0c38d1 SR |
836 | goto out; |
837 | ||
838 | found: | |
839 | *t = (*t)->next; | |
b5db03c4 ACM |
840 | |
841 | if (type == current_trace && tracer_enabled) { | |
842 | tracer_enabled = 0; | |
843 | tracing_stop(); | |
844 | if (current_trace->stop) | |
845 | current_trace->stop(&global_trace); | |
846 | current_trace = &nop_trace; | |
847 | } | |
ee6c2c1b | 848 | out: |
bc0c38d1 SR |
849 | mutex_unlock(&trace_types_lock); |
850 | } | |
851 | ||
283740c6 | 852 | static void __tracing_reset(struct ring_buffer *buffer, int cpu) |
bc0c38d1 | 853 | { |
d769041f | 854 | ftrace_disable_cpu(); |
283740c6 | 855 | ring_buffer_reset_cpu(buffer, cpu); |
d769041f | 856 | ftrace_enable_cpu(); |
bc0c38d1 SR |
857 | } |
858 | ||
f633903a SR |
859 | void tracing_reset(struct trace_array *tr, int cpu) |
860 | { | |
861 | struct ring_buffer *buffer = tr->buffer; | |
862 | ||
863 | ring_buffer_record_disable(buffer); | |
864 | ||
865 | /* Make sure all commits have finished */ | |
866 | synchronize_sched(); | |
283740c6 | 867 | __tracing_reset(buffer, cpu); |
f633903a SR |
868 | |
869 | ring_buffer_record_enable(buffer); | |
870 | } | |
871 | ||
213cc060 PE |
872 | void tracing_reset_online_cpus(struct trace_array *tr) |
873 | { | |
621968cd | 874 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
875 | int cpu; |
876 | ||
621968cd SR |
877 | ring_buffer_record_disable(buffer); |
878 | ||
879 | /* Make sure all commits have finished */ | |
880 | synchronize_sched(); | |
881 | ||
213cc060 PE |
882 | tr->time_start = ftrace_now(tr->cpu); |
883 | ||
884 | for_each_online_cpu(cpu) | |
283740c6 | 885 | __tracing_reset(buffer, cpu); |
621968cd SR |
886 | |
887 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
888 | } |
889 | ||
9456f0fa SR |
890 | void tracing_reset_current(int cpu) |
891 | { | |
892 | tracing_reset(&global_trace, cpu); | |
893 | } | |
894 | ||
895 | void tracing_reset_current_online_cpus(void) | |
896 | { | |
897 | tracing_reset_online_cpus(&global_trace); | |
898 | } | |
899 | ||
bc0c38d1 | 900 | #define SAVED_CMDLINES 128 |
2c7eea4c | 901 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
902 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
903 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
904 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
905 | static int cmdline_idx; | |
edc35bd7 | 906 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 907 | |
25b0b44a | 908 | /* temporary disable recording */ |
4fd27358 | 909 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
910 | |
911 | static void trace_init_cmdlines(void) | |
912 | { | |
2c7eea4c TG |
913 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
914 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
915 | cmdline_idx = 0; |
916 | } | |
917 | ||
b5130b1e CE |
918 | int is_tracing_stopped(void) |
919 | { | |
920 | return trace_stop_count; | |
921 | } | |
922 | ||
69bb54ec SR |
923 | /** |
924 | * ftrace_off_permanent - disable all ftrace code permanently | |
925 | * | |
926 | * This should only be called when a serious anomally has | |
927 | * been detected. This will turn off the function tracing, | |
928 | * ring buffers, and other tracing utilites. It takes no | |
929 | * locks and can be called from any context. | |
930 | */ | |
931 | void ftrace_off_permanent(void) | |
932 | { | |
933 | tracing_disabled = 1; | |
934 | ftrace_stop(); | |
935 | tracing_off_permanent(); | |
936 | } | |
937 | ||
0f048701 SR |
938 | /** |
939 | * tracing_start - quick start of the tracer | |
940 | * | |
941 | * If tracing is enabled but was stopped by tracing_stop, | |
942 | * this will start the tracer back up. | |
943 | */ | |
944 | void tracing_start(void) | |
945 | { | |
946 | struct ring_buffer *buffer; | |
947 | unsigned long flags; | |
948 | ||
949 | if (tracing_disabled) | |
950 | return; | |
951 | ||
952 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
953 | if (--trace_stop_count) { |
954 | if (trace_stop_count < 0) { | |
955 | /* Someone screwed up their debugging */ | |
956 | WARN_ON_ONCE(1); | |
957 | trace_stop_count = 0; | |
958 | } | |
0f048701 SR |
959 | goto out; |
960 | } | |
961 | ||
a2f80714 SR |
962 | /* Prevent the buffers from switching */ |
963 | arch_spin_lock(&ftrace_max_lock); | |
0f048701 SR |
964 | |
965 | buffer = global_trace.buffer; | |
966 | if (buffer) | |
967 | ring_buffer_record_enable(buffer); | |
968 | ||
969 | buffer = max_tr.buffer; | |
970 | if (buffer) | |
971 | ring_buffer_record_enable(buffer); | |
972 | ||
a2f80714 SR |
973 | arch_spin_unlock(&ftrace_max_lock); |
974 | ||
0f048701 SR |
975 | ftrace_start(); |
976 | out: | |
977 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
978 | } | |
979 | ||
980 | /** | |
981 | * tracing_stop - quick stop of the tracer | |
982 | * | |
983 | * Light weight way to stop tracing. Use in conjunction with | |
984 | * tracing_start. | |
985 | */ | |
986 | void tracing_stop(void) | |
987 | { | |
988 | struct ring_buffer *buffer; | |
989 | unsigned long flags; | |
990 | ||
991 | ftrace_stop(); | |
992 | spin_lock_irqsave(&tracing_start_lock, flags); | |
993 | if (trace_stop_count++) | |
994 | goto out; | |
995 | ||
a2f80714 SR |
996 | /* Prevent the buffers from switching */ |
997 | arch_spin_lock(&ftrace_max_lock); | |
998 | ||
0f048701 SR |
999 | buffer = global_trace.buffer; |
1000 | if (buffer) | |
1001 | ring_buffer_record_disable(buffer); | |
1002 | ||
1003 | buffer = max_tr.buffer; | |
1004 | if (buffer) | |
1005 | ring_buffer_record_disable(buffer); | |
1006 | ||
a2f80714 SR |
1007 | arch_spin_unlock(&ftrace_max_lock); |
1008 | ||
0f048701 SR |
1009 | out: |
1010 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
1011 | } | |
1012 | ||
e309b41d | 1013 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1014 | |
e309b41d | 1015 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1016 | { |
a635cf04 | 1017 | unsigned pid, idx; |
bc0c38d1 SR |
1018 | |
1019 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
1020 | return; | |
1021 | ||
1022 | /* | |
1023 | * It's not the end of the world if we don't get | |
1024 | * the lock, but we also don't want to spin | |
1025 | * nor do we want to disable interrupts, | |
1026 | * so if we miss here, then better luck next time. | |
1027 | */ | |
0199c4e6 | 1028 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
1029 | return; |
1030 | ||
1031 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1032 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1033 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1034 | ||
a635cf04 CE |
1035 | /* |
1036 | * Check whether the cmdline buffer at idx has a pid | |
1037 | * mapped. We are going to overwrite that entry so we | |
1038 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1039 | * would read the new comm for the old pid. | |
1040 | */ | |
1041 | pid = map_cmdline_to_pid[idx]; | |
1042 | if (pid != NO_CMDLINE_MAP) | |
1043 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1044 | |
a635cf04 | 1045 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1046 | map_pid_to_cmdline[tsk->pid] = idx; |
1047 | ||
1048 | cmdline_idx = idx; | |
1049 | } | |
1050 | ||
1051 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1052 | ||
0199c4e6 | 1053 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1054 | } |
1055 | ||
4ca53085 | 1056 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1057 | { |
bc0c38d1 SR |
1058 | unsigned map; |
1059 | ||
4ca53085 SR |
1060 | if (!pid) { |
1061 | strcpy(comm, "<idle>"); | |
1062 | return; | |
1063 | } | |
bc0c38d1 | 1064 | |
74bf4076 SR |
1065 | if (WARN_ON_ONCE(pid < 0)) { |
1066 | strcpy(comm, "<XXX>"); | |
1067 | return; | |
1068 | } | |
1069 | ||
4ca53085 SR |
1070 | if (pid > PID_MAX_DEFAULT) { |
1071 | strcpy(comm, "<...>"); | |
1072 | return; | |
1073 | } | |
bc0c38d1 | 1074 | |
5b6045a9 | 1075 | preempt_disable(); |
0199c4e6 | 1076 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1077 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1078 | if (map != NO_CMDLINE_MAP) |
1079 | strcpy(comm, saved_cmdlines[map]); | |
1080 | else | |
1081 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1082 | |
0199c4e6 | 1083 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1084 | preempt_enable(); |
bc0c38d1 SR |
1085 | } |
1086 | ||
e309b41d | 1087 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1088 | { |
18aecd36 TG |
1089 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
1090 | !tracing_is_on()) | |
bc0c38d1 SR |
1091 | return; |
1092 | ||
1093 | trace_save_cmdline(tsk); | |
1094 | } | |
1095 | ||
45dcd8b8 | 1096 | void |
38697053 SR |
1097 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1098 | int pc) | |
bc0c38d1 SR |
1099 | { |
1100 | struct task_struct *tsk = current; | |
bc0c38d1 | 1101 | |
777e208d SR |
1102 | entry->preempt_count = pc & 0xff; |
1103 | entry->pid = (tsk) ? tsk->pid : 0; | |
637e7e86 | 1104 | entry->lock_depth = (tsk) ? tsk->lock_depth : 0; |
777e208d | 1105 | entry->flags = |
9244489a | 1106 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1107 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1108 | #else |
1109 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1110 | #endif | |
bc0c38d1 SR |
1111 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1112 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1113 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1114 | } | |
f413cdb8 | 1115 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1116 | |
e77405ad SR |
1117 | struct ring_buffer_event * |
1118 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1119 | int type, | |
1120 | unsigned long len, | |
1121 | unsigned long flags, int pc) | |
51a763dd ACM |
1122 | { |
1123 | struct ring_buffer_event *event; | |
1124 | ||
e77405ad | 1125 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1126 | if (event != NULL) { |
1127 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1128 | ||
1129 | tracing_generic_entry_update(ent, flags, pc); | |
1130 | ent->type = type; | |
1131 | } | |
1132 | ||
1133 | return event; | |
1134 | } | |
51a763dd | 1135 | |
e77405ad SR |
1136 | static inline void |
1137 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1138 | struct ring_buffer_event *event, | |
1139 | unsigned long flags, int pc, | |
1140 | int wake) | |
51a763dd | 1141 | { |
e77405ad | 1142 | ring_buffer_unlock_commit(buffer, event); |
51a763dd | 1143 | |
e77405ad SR |
1144 | ftrace_trace_stack(buffer, flags, 6, pc); |
1145 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1146 | |
1147 | if (wake) | |
1148 | trace_wake_up(); | |
1149 | } | |
1150 | ||
e77405ad SR |
1151 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1152 | struct ring_buffer_event *event, | |
1153 | unsigned long flags, int pc) | |
07edf712 | 1154 | { |
e77405ad | 1155 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
51a763dd ACM |
1156 | } |
1157 | ||
ef5580d0 | 1158 | struct ring_buffer_event * |
e77405ad SR |
1159 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1160 | int type, unsigned long len, | |
ef5580d0 SR |
1161 | unsigned long flags, int pc) |
1162 | { | |
e77405ad SR |
1163 | *current_rb = global_trace.buffer; |
1164 | return trace_buffer_lock_reserve(*current_rb, | |
ef5580d0 SR |
1165 | type, len, flags, pc); |
1166 | } | |
94487d6d | 1167 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1168 | |
e77405ad SR |
1169 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1170 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1171 | unsigned long flags, int pc) |
1172 | { | |
e77405ad | 1173 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
07edf712 | 1174 | } |
94487d6d | 1175 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1176 | |
e77405ad SR |
1177 | void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer, |
1178 | struct ring_buffer_event *event, | |
1179 | unsigned long flags, int pc) | |
07edf712 | 1180 | { |
e77405ad | 1181 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 0); |
77d9f465 | 1182 | } |
94487d6d | 1183 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 | 1184 | |
e77405ad SR |
1185 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1186 | struct ring_buffer_event *event) | |
77d9f465 | 1187 | { |
e77405ad | 1188 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1189 | } |
12acd473 | 1190 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1191 | |
e309b41d | 1192 | void |
7be42151 | 1193 | trace_function(struct trace_array *tr, |
38697053 SR |
1194 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1195 | int pc) | |
bc0c38d1 | 1196 | { |
e1112b4d | 1197 | struct ftrace_event_call *call = &event_function; |
e77405ad | 1198 | struct ring_buffer *buffer = tr->buffer; |
3928a8a2 | 1199 | struct ring_buffer_event *event; |
777e208d | 1200 | struct ftrace_entry *entry; |
bc0c38d1 | 1201 | |
d769041f | 1202 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1203 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1204 | return; |
1205 | ||
e77405ad | 1206 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1207 | flags, pc); |
3928a8a2 SR |
1208 | if (!event) |
1209 | return; | |
1210 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1211 | entry->ip = ip; |
1212 | entry->parent_ip = parent_ip; | |
e1112b4d | 1213 | |
e77405ad SR |
1214 | if (!filter_check_discard(call, entry, buffer, event)) |
1215 | ring_buffer_unlock_commit(buffer, event); | |
bc0c38d1 SR |
1216 | } |
1217 | ||
e309b41d | 1218 | void |
2e0f5761 | 1219 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1220 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1221 | int pc) | |
2e0f5761 IM |
1222 | { |
1223 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1224 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1225 | } |
1226 | ||
c0a0d0d3 | 1227 | #ifdef CONFIG_STACKTRACE |
e77405ad | 1228 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 SR |
1229 | unsigned long flags, |
1230 | int skip, int pc) | |
86387f7e | 1231 | { |
e1112b4d | 1232 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1233 | struct ring_buffer_event *event; |
777e208d | 1234 | struct stack_entry *entry; |
86387f7e IM |
1235 | struct stack_trace trace; |
1236 | ||
e77405ad | 1237 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
51a763dd | 1238 | sizeof(*entry), flags, pc); |
3928a8a2 SR |
1239 | if (!event) |
1240 | return; | |
1241 | entry = ring_buffer_event_data(event); | |
777e208d | 1242 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
1243 | |
1244 | trace.nr_entries = 0; | |
1245 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1246 | trace.skip = skip; | |
777e208d | 1247 | trace.entries = entry->caller; |
86387f7e IM |
1248 | |
1249 | save_stack_trace(&trace); | |
e77405ad SR |
1250 | if (!filter_check_discard(call, entry, buffer, event)) |
1251 | ring_buffer_unlock_commit(buffer, event); | |
f0a920d5 IM |
1252 | } |
1253 | ||
e77405ad SR |
1254 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1255 | int skip, int pc) | |
53614991 SR |
1256 | { |
1257 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1258 | return; | |
1259 | ||
e77405ad | 1260 | __ftrace_trace_stack(buffer, flags, skip, pc); |
53614991 SR |
1261 | } |
1262 | ||
c0a0d0d3 FW |
1263 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1264 | int pc) | |
38697053 | 1265 | { |
e77405ad | 1266 | __ftrace_trace_stack(tr->buffer, flags, skip, pc); |
38697053 SR |
1267 | } |
1268 | ||
03889384 SR |
1269 | /** |
1270 | * trace_dump_stack - record a stack back trace in the trace buffer | |
1271 | */ | |
1272 | void trace_dump_stack(void) | |
1273 | { | |
1274 | unsigned long flags; | |
1275 | ||
1276 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1277 | return; |
03889384 SR |
1278 | |
1279 | local_save_flags(flags); | |
1280 | ||
1281 | /* skipping 3 traces, seems to get us at the caller of this function */ | |
1282 | __ftrace_trace_stack(global_trace.buffer, flags, 3, preempt_count()); | |
1283 | } | |
1284 | ||
91e86e56 SR |
1285 | static DEFINE_PER_CPU(int, user_stack_count); |
1286 | ||
e77405ad SR |
1287 | void |
1288 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1289 | { |
e1112b4d | 1290 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1291 | struct ring_buffer_event *event; |
02b67518 TE |
1292 | struct userstack_entry *entry; |
1293 | struct stack_trace trace; | |
02b67518 TE |
1294 | |
1295 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1296 | return; | |
1297 | ||
b6345879 SR |
1298 | /* |
1299 | * NMIs can not handle page faults, even with fix ups. | |
1300 | * The save user stack can (and often does) fault. | |
1301 | */ | |
1302 | if (unlikely(in_nmi())) | |
1303 | return; | |
02b67518 | 1304 | |
91e86e56 SR |
1305 | /* |
1306 | * prevent recursion, since the user stack tracing may | |
1307 | * trigger other kernel events. | |
1308 | */ | |
1309 | preempt_disable(); | |
1310 | if (__this_cpu_read(user_stack_count)) | |
1311 | goto out; | |
1312 | ||
1313 | __this_cpu_inc(user_stack_count); | |
1314 | ||
e77405ad | 1315 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1316 | sizeof(*entry), flags, pc); |
02b67518 | 1317 | if (!event) |
1dbd1951 | 1318 | goto out_drop_count; |
02b67518 | 1319 | entry = ring_buffer_event_data(event); |
02b67518 | 1320 | |
48659d31 | 1321 | entry->tgid = current->tgid; |
02b67518 TE |
1322 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1323 | ||
1324 | trace.nr_entries = 0; | |
1325 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1326 | trace.skip = 0; | |
1327 | trace.entries = entry->caller; | |
1328 | ||
1329 | save_stack_trace_user(&trace); | |
e77405ad SR |
1330 | if (!filter_check_discard(call, entry, buffer, event)) |
1331 | ring_buffer_unlock_commit(buffer, event); | |
91e86e56 | 1332 | |
1dbd1951 | 1333 | out_drop_count: |
91e86e56 | 1334 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1335 | out: |
1336 | preempt_enable(); | |
02b67518 TE |
1337 | } |
1338 | ||
4fd27358 HE |
1339 | #ifdef UNUSED |
1340 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1341 | { |
7be42151 | 1342 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1343 | } |
4fd27358 | 1344 | #endif /* UNUSED */ |
02b67518 | 1345 | |
c0a0d0d3 FW |
1346 | #endif /* CONFIG_STACKTRACE */ |
1347 | ||
769b0441 | 1348 | /** |
48ead020 | 1349 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1350 | * |
1351 | */ | |
40ce74f1 | 1352 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1353 | { |
445c8951 | 1354 | static arch_spinlock_t trace_buf_lock = |
edc35bd7 | 1355 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
769b0441 FW |
1356 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1357 | ||
e1112b4d | 1358 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1359 | struct ring_buffer_event *event; |
e77405ad | 1360 | struct ring_buffer *buffer; |
769b0441 FW |
1361 | struct trace_array *tr = &global_trace; |
1362 | struct trace_array_cpu *data; | |
48ead020 | 1363 | struct bprint_entry *entry; |
769b0441 | 1364 | unsigned long flags; |
3189cdb3 | 1365 | int disable; |
769b0441 FW |
1366 | int cpu, len = 0, size, pc; |
1367 | ||
1368 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1369 | return 0; | |
1370 | ||
1371 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1372 | pause_graph_tracing(); | |
1373 | ||
1374 | pc = preempt_count(); | |
5168ae50 | 1375 | preempt_disable_notrace(); |
769b0441 FW |
1376 | cpu = raw_smp_processor_id(); |
1377 | data = tr->data[cpu]; | |
1378 | ||
3189cdb3 SR |
1379 | disable = atomic_inc_return(&data->disabled); |
1380 | if (unlikely(disable != 1)) | |
769b0441 FW |
1381 | goto out; |
1382 | ||
80370cb7 SR |
1383 | /* Lockdep uses trace_printk for lock tracing */ |
1384 | local_irq_save(flags); | |
0199c4e6 | 1385 | arch_spin_lock(&trace_buf_lock); |
769b0441 FW |
1386 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1387 | ||
1388 | if (len > TRACE_BUF_SIZE || len < 0) | |
1389 | goto out_unlock; | |
1390 | ||
1391 | size = sizeof(*entry) + sizeof(u32) * len; | |
e77405ad SR |
1392 | buffer = tr->buffer; |
1393 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, | |
1394 | flags, pc); | |
769b0441 FW |
1395 | if (!event) |
1396 | goto out_unlock; | |
1397 | entry = ring_buffer_event_data(event); | |
1398 | entry->ip = ip; | |
769b0441 FW |
1399 | entry->fmt = fmt; |
1400 | ||
1401 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
d931369b | 1402 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1403 | ring_buffer_unlock_commit(buffer, event); |
d931369b SR |
1404 | ftrace_trace_stack(buffer, flags, 6, pc); |
1405 | } | |
769b0441 FW |
1406 | |
1407 | out_unlock: | |
0199c4e6 | 1408 | arch_spin_unlock(&trace_buf_lock); |
80370cb7 | 1409 | local_irq_restore(flags); |
769b0441 FW |
1410 | |
1411 | out: | |
3189cdb3 | 1412 | atomic_dec_return(&data->disabled); |
5168ae50 | 1413 | preempt_enable_notrace(); |
769b0441 FW |
1414 | unpause_graph_tracing(); |
1415 | ||
1416 | return len; | |
1417 | } | |
48ead020 FW |
1418 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1419 | ||
659372d3 SR |
1420 | int trace_array_printk(struct trace_array *tr, |
1421 | unsigned long ip, const char *fmt, ...) | |
1422 | { | |
1423 | int ret; | |
1424 | va_list ap; | |
1425 | ||
1426 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1427 | return 0; | |
1428 | ||
1429 | va_start(ap, fmt); | |
1430 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
1431 | va_end(ap); | |
1432 | return ret; | |
1433 | } | |
1434 | ||
1435 | int trace_array_vprintk(struct trace_array *tr, | |
1436 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 1437 | { |
edc35bd7 | 1438 | static arch_spinlock_t trace_buf_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
48ead020 FW |
1439 | static char trace_buf[TRACE_BUF_SIZE]; |
1440 | ||
e1112b4d | 1441 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1442 | struct ring_buffer_event *event; |
e77405ad | 1443 | struct ring_buffer *buffer; |
48ead020 FW |
1444 | struct trace_array_cpu *data; |
1445 | int cpu, len = 0, size, pc; | |
1446 | struct print_entry *entry; | |
1447 | unsigned long irq_flags; | |
3189cdb3 | 1448 | int disable; |
48ead020 FW |
1449 | |
1450 | if (tracing_disabled || tracing_selftest_running) | |
1451 | return 0; | |
1452 | ||
1453 | pc = preempt_count(); | |
1454 | preempt_disable_notrace(); | |
1455 | cpu = raw_smp_processor_id(); | |
1456 | data = tr->data[cpu]; | |
1457 | ||
3189cdb3 SR |
1458 | disable = atomic_inc_return(&data->disabled); |
1459 | if (unlikely(disable != 1)) | |
48ead020 FW |
1460 | goto out; |
1461 | ||
1462 | pause_graph_tracing(); | |
1463 | raw_local_irq_save(irq_flags); | |
0199c4e6 | 1464 | arch_spin_lock(&trace_buf_lock); |
f2942487 | 1465 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
48ead020 FW |
1466 | |
1467 | size = sizeof(*entry) + len + 1; | |
e77405ad SR |
1468 | buffer = tr->buffer; |
1469 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
1470 | irq_flags, pc); | |
48ead020 FW |
1471 | if (!event) |
1472 | goto out_unlock; | |
1473 | entry = ring_buffer_event_data(event); | |
c13d2f7c | 1474 | entry->ip = ip; |
48ead020 FW |
1475 | |
1476 | memcpy(&entry->buf, trace_buf, len); | |
c13d2f7c | 1477 | entry->buf[len] = '\0'; |
d931369b | 1478 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1479 | ring_buffer_unlock_commit(buffer, event); |
d931369b SR |
1480 | ftrace_trace_stack(buffer, irq_flags, 6, pc); |
1481 | } | |
48ead020 FW |
1482 | |
1483 | out_unlock: | |
0199c4e6 | 1484 | arch_spin_unlock(&trace_buf_lock); |
48ead020 FW |
1485 | raw_local_irq_restore(irq_flags); |
1486 | unpause_graph_tracing(); | |
1487 | out: | |
3189cdb3 | 1488 | atomic_dec_return(&data->disabled); |
48ead020 FW |
1489 | preempt_enable_notrace(); |
1490 | ||
1491 | return len; | |
1492 | } | |
659372d3 SR |
1493 | |
1494 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) | |
1495 | { | |
a813a159 | 1496 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 1497 | } |
769b0441 FW |
1498 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1499 | ||
e2ac8ef5 | 1500 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1501 | { |
d769041f SR |
1502 | /* Don't allow ftrace to trace into the ring buffers */ |
1503 | ftrace_disable_cpu(); | |
1504 | ||
5a90f577 | 1505 | iter->idx++; |
d769041f SR |
1506 | if (iter->buffer_iter[iter->cpu]) |
1507 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1508 | ||
1509 | ftrace_enable_cpu(); | |
5a90f577 SR |
1510 | } |
1511 | ||
e309b41d | 1512 | static struct trace_entry * |
bc21b478 SR |
1513 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
1514 | unsigned long *lost_events) | |
dd0e545f | 1515 | { |
3928a8a2 SR |
1516 | struct ring_buffer_event *event; |
1517 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1518 | |
d769041f SR |
1519 | /* Don't allow ftrace to trace into the ring buffers */ |
1520 | ftrace_disable_cpu(); | |
1521 | ||
1522 | if (buf_iter) | |
1523 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1524 | else | |
bc21b478 SR |
1525 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts, |
1526 | lost_events); | |
d769041f SR |
1527 | |
1528 | ftrace_enable_cpu(); | |
1529 | ||
3928a8a2 | 1530 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1531 | } |
d769041f | 1532 | |
dd0e545f | 1533 | static struct trace_entry * |
bc21b478 SR |
1534 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
1535 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 1536 | { |
3928a8a2 | 1537 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1538 | struct trace_entry *ent, *next = NULL; |
aa27497c | 1539 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 1540 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1541 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1542 | int next_cpu = -1; |
1543 | int cpu; | |
1544 | ||
b04cc6b1 FW |
1545 | /* |
1546 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1547 | * all cpu and peek directly. | |
1548 | */ | |
1549 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1550 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1551 | return NULL; | |
bc21b478 | 1552 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
1553 | if (ent_cpu) |
1554 | *ent_cpu = cpu_file; | |
1555 | ||
1556 | return ent; | |
1557 | } | |
1558 | ||
ab46428c | 1559 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1560 | |
3928a8a2 SR |
1561 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1562 | continue; | |
dd0e545f | 1563 | |
bc21b478 | 1564 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 1565 | |
cdd31cd2 IM |
1566 | /* |
1567 | * Pick the entry with the smallest timestamp: | |
1568 | */ | |
3928a8a2 | 1569 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1570 | next = ent; |
1571 | next_cpu = cpu; | |
3928a8a2 | 1572 | next_ts = ts; |
bc21b478 | 1573 | next_lost = lost_events; |
bc0c38d1 SR |
1574 | } |
1575 | } | |
1576 | ||
1577 | if (ent_cpu) | |
1578 | *ent_cpu = next_cpu; | |
1579 | ||
3928a8a2 SR |
1580 | if (ent_ts) |
1581 | *ent_ts = next_ts; | |
1582 | ||
bc21b478 SR |
1583 | if (missing_events) |
1584 | *missing_events = next_lost; | |
1585 | ||
bc0c38d1 SR |
1586 | return next; |
1587 | } | |
1588 | ||
dd0e545f | 1589 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1590 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1591 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1592 | { |
bc21b478 | 1593 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
1594 | } |
1595 | ||
1596 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 1597 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 1598 | { |
bc21b478 SR |
1599 | iter->ent = __find_next_entry(iter, &iter->cpu, |
1600 | &iter->lost_events, &iter->ts); | |
dd0e545f | 1601 | |
3928a8a2 | 1602 | if (iter->ent) |
e2ac8ef5 | 1603 | trace_iterator_increment(iter); |
dd0e545f | 1604 | |
3928a8a2 | 1605 | return iter->ent ? iter : NULL; |
b3806b43 | 1606 | } |
bc0c38d1 | 1607 | |
e309b41d | 1608 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1609 | { |
d769041f SR |
1610 | /* Don't allow ftrace to trace into the ring buffers */ |
1611 | ftrace_disable_cpu(); | |
bc21b478 SR |
1612 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts, |
1613 | &iter->lost_events); | |
d769041f | 1614 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1615 | } |
1616 | ||
e309b41d | 1617 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1618 | { |
1619 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1620 | int i = (int)*pos; |
4e3c3333 | 1621 | void *ent; |
bc0c38d1 | 1622 | |
a63ce5b3 SR |
1623 | WARN_ON_ONCE(iter->leftover); |
1624 | ||
bc0c38d1 SR |
1625 | (*pos)++; |
1626 | ||
1627 | /* can't go backwards */ | |
1628 | if (iter->idx > i) | |
1629 | return NULL; | |
1630 | ||
1631 | if (iter->idx < 0) | |
955b61e5 | 1632 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1633 | else |
1634 | ent = iter; | |
1635 | ||
1636 | while (ent && iter->idx < i) | |
955b61e5 | 1637 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1638 | |
1639 | iter->pos = *pos; | |
1640 | ||
bc0c38d1 SR |
1641 | return ent; |
1642 | } | |
1643 | ||
955b61e5 | 1644 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 SR |
1645 | { |
1646 | struct trace_array *tr = iter->tr; | |
1647 | struct ring_buffer_event *event; | |
1648 | struct ring_buffer_iter *buf_iter; | |
1649 | unsigned long entries = 0; | |
1650 | u64 ts; | |
1651 | ||
1652 | tr->data[cpu]->skipped_entries = 0; | |
1653 | ||
1654 | if (!iter->buffer_iter[cpu]) | |
1655 | return; | |
1656 | ||
1657 | buf_iter = iter->buffer_iter[cpu]; | |
1658 | ring_buffer_iter_reset(buf_iter); | |
1659 | ||
1660 | /* | |
1661 | * We could have the case with the max latency tracers | |
1662 | * that a reset never took place on a cpu. This is evident | |
1663 | * by the timestamp being before the start of the buffer. | |
1664 | */ | |
1665 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
1666 | if (ts >= iter->tr->time_start) | |
1667 | break; | |
1668 | entries++; | |
1669 | ring_buffer_read(buf_iter, NULL); | |
1670 | } | |
1671 | ||
1672 | tr->data[cpu]->skipped_entries = entries; | |
1673 | } | |
1674 | ||
d7350c3f | 1675 | /* |
d7350c3f FW |
1676 | * The current tracer is copied to avoid a global locking |
1677 | * all around. | |
1678 | */ | |
bc0c38d1 SR |
1679 | static void *s_start(struct seq_file *m, loff_t *pos) |
1680 | { | |
1681 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1682 | static struct tracer *old_tracer; |
b04cc6b1 | 1683 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1684 | void *p = NULL; |
1685 | loff_t l = 0; | |
3928a8a2 | 1686 | int cpu; |
bc0c38d1 | 1687 | |
d7350c3f | 1688 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1689 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1690 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1691 | old_tracer = current_trace; | |
1692 | *iter->trace = *current_trace; | |
d15f57f2 | 1693 | } |
d7350c3f | 1694 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1695 | |
1696 | atomic_inc(&trace_record_cmdline_disabled); | |
1697 | ||
bc0c38d1 SR |
1698 | if (*pos != iter->pos) { |
1699 | iter->ent = NULL; | |
1700 | iter->cpu = 0; | |
1701 | iter->idx = -1; | |
1702 | ||
d769041f SR |
1703 | ftrace_disable_cpu(); |
1704 | ||
b04cc6b1 FW |
1705 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1706 | for_each_tracing_cpu(cpu) | |
2f26ebd5 | 1707 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 1708 | } else |
2f26ebd5 | 1709 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 1710 | |
d769041f SR |
1711 | ftrace_enable_cpu(); |
1712 | ||
ac91d854 | 1713 | iter->leftover = 0; |
bc0c38d1 SR |
1714 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1715 | ; | |
1716 | ||
1717 | } else { | |
a63ce5b3 SR |
1718 | /* |
1719 | * If we overflowed the seq_file before, then we want | |
1720 | * to just reuse the trace_seq buffer again. | |
1721 | */ | |
1722 | if (iter->leftover) | |
1723 | p = iter; | |
1724 | else { | |
1725 | l = *pos - 1; | |
1726 | p = s_next(m, p, &l); | |
1727 | } | |
bc0c38d1 SR |
1728 | } |
1729 | ||
4f535968 | 1730 | trace_event_read_lock(); |
7e53bd42 | 1731 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
1732 | return p; |
1733 | } | |
1734 | ||
1735 | static void s_stop(struct seq_file *m, void *p) | |
1736 | { | |
7e53bd42 LJ |
1737 | struct trace_iterator *iter = m->private; |
1738 | ||
bc0c38d1 | 1739 | atomic_dec(&trace_record_cmdline_disabled); |
7e53bd42 | 1740 | trace_access_unlock(iter->cpu_file); |
4f535968 | 1741 | trace_event_read_unlock(); |
bc0c38d1 SR |
1742 | } |
1743 | ||
e309b41d | 1744 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1745 | { |
a6168353 ME |
1746 | seq_puts(m, "# _------=> CPU# \n"); |
1747 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1748 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1749 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1750 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
637e7e86 SR |
1751 | seq_puts(m, "# |||| /_--=> lock-depth \n"); |
1752 | seq_puts(m, "# |||||/ delay \n"); | |
1753 | seq_puts(m, "# cmd pid |||||| time | caller \n"); | |
1754 | seq_puts(m, "# \\ / |||||| \\ | / \n"); | |
bc0c38d1 SR |
1755 | } |
1756 | ||
e309b41d | 1757 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1758 | { |
a6168353 ME |
1759 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1760 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1761 | } |
1762 | ||
1763 | ||
62b915f1 | 1764 | void |
bc0c38d1 SR |
1765 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1766 | { | |
1767 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1768 | struct trace_array *tr = iter->tr; | |
1769 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1770 | struct tracer *type = current_trace; | |
2f26ebd5 SR |
1771 | unsigned long entries = 0; |
1772 | unsigned long total = 0; | |
1773 | unsigned long count; | |
bc0c38d1 | 1774 | const char *name = "preemption"; |
2f26ebd5 | 1775 | int cpu; |
bc0c38d1 SR |
1776 | |
1777 | if (type) | |
1778 | name = type->name; | |
1779 | ||
2f26ebd5 SR |
1780 | |
1781 | for_each_tracing_cpu(cpu) { | |
1782 | count = ring_buffer_entries_cpu(tr->buffer, cpu); | |
1783 | /* | |
1784 | * If this buffer has skipped entries, then we hold all | |
1785 | * entries for the trace and we need to ignore the | |
1786 | * ones before the time stamp. | |
1787 | */ | |
1788 | if (tr->data[cpu]->skipped_entries) { | |
1789 | count -= tr->data[cpu]->skipped_entries; | |
1790 | /* total is the same as the entries */ | |
1791 | total += count; | |
1792 | } else | |
1793 | total += count + | |
1794 | ring_buffer_overrun_cpu(tr->buffer, cpu); | |
1795 | entries += count; | |
1796 | } | |
bc0c38d1 | 1797 | |
888b55dc | 1798 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1799 | name, UTS_RELEASE); |
888b55dc | 1800 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1801 | "---------------------------------\n"); |
888b55dc | 1802 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1803 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1804 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1805 | entries, |
4c11d7ae | 1806 | total, |
bc0c38d1 SR |
1807 | tr->cpu, |
1808 | #if defined(CONFIG_PREEMPT_NONE) | |
1809 | "server", | |
1810 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1811 | "desktop", | |
b5c21b45 | 1812 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1813 | "preempt", |
1814 | #else | |
1815 | "unknown", | |
1816 | #endif | |
1817 | /* These are reserved for later use */ | |
1818 | 0, 0, 0, 0); | |
1819 | #ifdef CONFIG_SMP | |
1820 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1821 | #else | |
1822 | seq_puts(m, ")\n"); | |
1823 | #endif | |
888b55dc KM |
1824 | seq_puts(m, "# -----------------\n"); |
1825 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1826 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1827 | data->comm, data->pid, data->uid, data->nice, | |
1828 | data->policy, data->rt_priority); | |
888b55dc | 1829 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1830 | |
1831 | if (data->critical_start) { | |
888b55dc | 1832 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1833 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1834 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1835 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1836 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1837 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 1838 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
1839 | } |
1840 | ||
888b55dc | 1841 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1842 | } |
1843 | ||
a309720c SR |
1844 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1845 | { | |
1846 | struct trace_seq *s = &iter->seq; | |
1847 | ||
12ef7d44 SR |
1848 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1849 | return; | |
1850 | ||
1851 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1852 | return; | |
1853 | ||
4462344e | 1854 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1855 | return; |
1856 | ||
2f26ebd5 SR |
1857 | if (iter->tr->data[iter->cpu]->skipped_entries) |
1858 | return; | |
1859 | ||
4462344e | 1860 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1861 | |
1862 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1863 | if (iter->idx > 1) | |
1864 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1865 | iter->cpu); | |
a309720c SR |
1866 | } |
1867 | ||
2c4f035f | 1868 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1869 | { |
214023c3 | 1870 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1871 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1872 | struct trace_entry *entry; |
f633cef0 | 1873 | struct trace_event *event; |
bc0c38d1 | 1874 | |
4e3c3333 | 1875 | entry = iter->ent; |
dd0e545f | 1876 | |
a309720c SR |
1877 | test_cpu_buff_start(iter); |
1878 | ||
c4a8e8be | 1879 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1880 | |
c4a8e8be | 1881 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1882 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1883 | if (!trace_print_lat_context(iter)) | |
1884 | goto partial; | |
1885 | } else { | |
1886 | if (!trace_print_context(iter)) | |
1887 | goto partial; | |
1888 | } | |
c4a8e8be | 1889 | } |
bc0c38d1 | 1890 | |
268ccda0 | 1891 | if (event) |
a9a57763 | 1892 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
1893 | |
1894 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1895 | goto partial; | |
02b67518 | 1896 | |
2c4f035f | 1897 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1898 | partial: |
1899 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1900 | } |
1901 | ||
2c4f035f | 1902 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1903 | { |
1904 | struct trace_seq *s = &iter->seq; | |
1905 | struct trace_entry *entry; | |
f633cef0 | 1906 | struct trace_event *event; |
f9896bf3 IM |
1907 | |
1908 | entry = iter->ent; | |
dd0e545f | 1909 | |
c4a8e8be | 1910 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1911 | if (!trace_seq_printf(s, "%d %d %llu ", |
1912 | entry->pid, iter->cpu, iter->ts)) | |
1913 | goto partial; | |
c4a8e8be | 1914 | } |
f9896bf3 | 1915 | |
f633cef0 | 1916 | event = ftrace_find_event(entry->type); |
268ccda0 | 1917 | if (event) |
a9a57763 | 1918 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
1919 | |
1920 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1921 | goto partial; | |
777e208d | 1922 | |
2c4f035f | 1923 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1924 | partial: |
1925 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1926 | } |
1927 | ||
2c4f035f | 1928 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1929 | { |
1930 | struct trace_seq *s = &iter->seq; | |
1931 | unsigned char newline = '\n'; | |
1932 | struct trace_entry *entry; | |
f633cef0 | 1933 | struct trace_event *event; |
5e3ca0ec IM |
1934 | |
1935 | entry = iter->ent; | |
dd0e545f | 1936 | |
c4a8e8be FW |
1937 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1938 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1939 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1940 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1941 | } | |
5e3ca0ec | 1942 | |
f633cef0 | 1943 | event = ftrace_find_event(entry->type); |
268ccda0 | 1944 | if (event) { |
a9a57763 | 1945 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
1946 | if (ret != TRACE_TYPE_HANDLED) |
1947 | return ret; | |
1948 | } | |
7104f300 | 1949 | |
5e3ca0ec IM |
1950 | SEQ_PUT_FIELD_RET(s, newline); |
1951 | ||
2c4f035f | 1952 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1953 | } |
1954 | ||
2c4f035f | 1955 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1956 | { |
1957 | struct trace_seq *s = &iter->seq; | |
1958 | struct trace_entry *entry; | |
f633cef0 | 1959 | struct trace_event *event; |
cb0f12aa IM |
1960 | |
1961 | entry = iter->ent; | |
dd0e545f | 1962 | |
c4a8e8be FW |
1963 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1964 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1965 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1966 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1967 | } | |
cb0f12aa | 1968 | |
f633cef0 | 1969 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
1970 | return event ? event->funcs->binary(iter, 0, event) : |
1971 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
1972 | } |
1973 | ||
62b915f1 | 1974 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 1975 | { |
bc0c38d1 SR |
1976 | int cpu; |
1977 | ||
9aba60fe SR |
1978 | /* If we are looking at one CPU buffer, only check that one */ |
1979 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1980 | cpu = iter->cpu_file; | |
1981 | if (iter->buffer_iter[cpu]) { | |
1982 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1983 | return 0; | |
1984 | } else { | |
1985 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1986 | return 0; | |
1987 | } | |
1988 | return 1; | |
1989 | } | |
1990 | ||
ab46428c | 1991 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1992 | if (iter->buffer_iter[cpu]) { |
1993 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1994 | return 0; | |
1995 | } else { | |
1996 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1997 | return 0; | |
1998 | } | |
bc0c38d1 | 1999 | } |
d769041f | 2000 | |
797d3712 | 2001 | return 1; |
bc0c38d1 SR |
2002 | } |
2003 | ||
4f535968 | 2004 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2005 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2006 | { |
2c4f035f FW |
2007 | enum print_line_t ret; |
2008 | ||
bc21b478 SR |
2009 | if (iter->lost_events) |
2010 | trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2011 | iter->cpu, iter->lost_events); | |
2012 | ||
2c4f035f FW |
2013 | if (iter->trace && iter->trace->print_line) { |
2014 | ret = iter->trace->print_line(iter); | |
2015 | if (ret != TRACE_TYPE_UNHANDLED) | |
2016 | return ret; | |
2017 | } | |
72829bc3 | 2018 | |
48ead020 FW |
2019 | if (iter->ent->type == TRACE_BPRINT && |
2020 | trace_flags & TRACE_ITER_PRINTK && | |
2021 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2022 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2023 | |
66896a85 FW |
2024 | if (iter->ent->type == TRACE_PRINT && |
2025 | trace_flags & TRACE_ITER_PRINTK && | |
2026 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2027 | return trace_print_printk_msg_only(iter); |
66896a85 | 2028 | |
cb0f12aa IM |
2029 | if (trace_flags & TRACE_ITER_BIN) |
2030 | return print_bin_fmt(iter); | |
2031 | ||
5e3ca0ec IM |
2032 | if (trace_flags & TRACE_ITER_HEX) |
2033 | return print_hex_fmt(iter); | |
2034 | ||
f9896bf3 IM |
2035 | if (trace_flags & TRACE_ITER_RAW) |
2036 | return print_raw_fmt(iter); | |
2037 | ||
f9896bf3 IM |
2038 | return print_trace_fmt(iter); |
2039 | } | |
2040 | ||
62b915f1 JO |
2041 | void trace_default_header(struct seq_file *m) |
2042 | { | |
2043 | struct trace_iterator *iter = m->private; | |
2044 | ||
2045 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
2046 | /* print nothing if the buffers are empty */ | |
2047 | if (trace_empty(iter)) | |
2048 | return; | |
2049 | print_trace_header(m, iter); | |
2050 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2051 | print_lat_help_header(m); | |
2052 | } else { | |
2053 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2054 | print_func_help_header(m); | |
2055 | } | |
2056 | } | |
2057 | ||
bc0c38d1 SR |
2058 | static int s_show(struct seq_file *m, void *v) |
2059 | { | |
2060 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2061 | int ret; |
bc0c38d1 SR |
2062 | |
2063 | if (iter->ent == NULL) { | |
2064 | if (iter->tr) { | |
2065 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2066 | seq_puts(m, "#\n"); | |
2067 | } | |
8bba1bf5 MM |
2068 | if (iter->trace && iter->trace->print_header) |
2069 | iter->trace->print_header(m); | |
62b915f1 JO |
2070 | else |
2071 | trace_default_header(m); | |
2072 | ||
a63ce5b3 SR |
2073 | } else if (iter->leftover) { |
2074 | /* | |
2075 | * If we filled the seq_file buffer earlier, we | |
2076 | * want to just show it now. | |
2077 | */ | |
2078 | ret = trace_print_seq(m, &iter->seq); | |
2079 | ||
2080 | /* ret should this time be zero, but you never know */ | |
2081 | iter->leftover = ret; | |
2082 | ||
bc0c38d1 | 2083 | } else { |
f9896bf3 | 2084 | print_trace_line(iter); |
a63ce5b3 SR |
2085 | ret = trace_print_seq(m, &iter->seq); |
2086 | /* | |
2087 | * If we overflow the seq_file buffer, then it will | |
2088 | * ask us for this data again at start up. | |
2089 | * Use that instead. | |
2090 | * ret is 0 if seq_file write succeeded. | |
2091 | * -1 otherwise. | |
2092 | */ | |
2093 | iter->leftover = ret; | |
bc0c38d1 SR |
2094 | } |
2095 | ||
2096 | return 0; | |
2097 | } | |
2098 | ||
88e9d34c | 2099 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2100 | .start = s_start, |
2101 | .next = s_next, | |
2102 | .stop = s_stop, | |
2103 | .show = s_show, | |
bc0c38d1 SR |
2104 | }; |
2105 | ||
e309b41d | 2106 | static struct trace_iterator * |
85a2f9b4 | 2107 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 2108 | { |
b04cc6b1 | 2109 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 2110 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 2111 | struct trace_iterator *iter; |
3928a8a2 | 2112 | struct seq_file *m; |
85a2f9b4 | 2113 | int cpu, ret; |
bc0c38d1 | 2114 | |
85a2f9b4 SR |
2115 | if (tracing_disabled) |
2116 | return ERR_PTR(-ENODEV); | |
60a11774 | 2117 | |
bc0c38d1 | 2118 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
2119 | if (!iter) |
2120 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2121 | |
d7350c3f FW |
2122 | /* |
2123 | * We make a copy of the current tracer to avoid concurrent | |
2124 | * changes on it while we are reading. | |
2125 | */ | |
bc0c38d1 | 2126 | mutex_lock(&trace_types_lock); |
d7350c3f | 2127 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2128 | if (!iter->trace) |
d7350c3f | 2129 | goto fail; |
85a2f9b4 | 2130 | |
d7350c3f FW |
2131 | if (current_trace) |
2132 | *iter->trace = *current_trace; | |
2133 | ||
79f55997 | 2134 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2135 | goto fail; |
2136 | ||
bc0c38d1 SR |
2137 | if (current_trace && current_trace->print_max) |
2138 | iter->tr = &max_tr; | |
2139 | else | |
b04cc6b1 | 2140 | iter->tr = &global_trace; |
bc0c38d1 | 2141 | iter->pos = -1; |
d7350c3f | 2142 | mutex_init(&iter->mutex); |
b04cc6b1 | 2143 | iter->cpu_file = cpu_file; |
bc0c38d1 | 2144 | |
8bba1bf5 MM |
2145 | /* Notify the tracer early; before we stop tracing. */ |
2146 | if (iter->trace && iter->trace->open) | |
a93751ca | 2147 | iter->trace->open(iter); |
8bba1bf5 | 2148 | |
12ef7d44 SR |
2149 | /* Annotate start of buffers if we had overruns */ |
2150 | if (ring_buffer_overruns(iter->tr->buffer)) | |
2151 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
2152 | ||
2f26ebd5 SR |
2153 | /* stop the trace while dumping */ |
2154 | tracing_stop(); | |
2155 | ||
b04cc6b1 FW |
2156 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
2157 | for_each_tracing_cpu(cpu) { | |
b04cc6b1 | 2158 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2159 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2160 | } | |
2161 | ring_buffer_read_prepare_sync(); | |
2162 | for_each_tracing_cpu(cpu) { | |
2163 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2164 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2165 | } |
2166 | } else { | |
2167 | cpu = iter->cpu_file; | |
3928a8a2 | 2168 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2169 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2170 | ring_buffer_read_prepare_sync(); | |
2171 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2172 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2173 | } |
2174 | ||
85a2f9b4 SR |
2175 | ret = seq_open(file, &tracer_seq_ops); |
2176 | if (ret < 0) { | |
2177 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 2178 | goto fail_buffer; |
85a2f9b4 | 2179 | } |
bc0c38d1 | 2180 | |
3928a8a2 SR |
2181 | m = file->private_data; |
2182 | m->private = iter; | |
bc0c38d1 | 2183 | |
bc0c38d1 SR |
2184 | mutex_unlock(&trace_types_lock); |
2185 | ||
bc0c38d1 | 2186 | return iter; |
3928a8a2 SR |
2187 | |
2188 | fail_buffer: | |
2189 | for_each_tracing_cpu(cpu) { | |
2190 | if (iter->buffer_iter[cpu]) | |
2191 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2192 | } | |
b0dfa978 | 2193 | free_cpumask_var(iter->started); |
2f26ebd5 | 2194 | tracing_start(); |
d7350c3f | 2195 | fail: |
3928a8a2 | 2196 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2197 | kfree(iter->trace); |
0bb943c7 | 2198 | kfree(iter); |
3928a8a2 | 2199 | |
85a2f9b4 | 2200 | return fail_ret; |
bc0c38d1 SR |
2201 | } |
2202 | ||
2203 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2204 | { | |
60a11774 SR |
2205 | if (tracing_disabled) |
2206 | return -ENODEV; | |
2207 | ||
bc0c38d1 SR |
2208 | filp->private_data = inode->i_private; |
2209 | return 0; | |
2210 | } | |
2211 | ||
4fd27358 | 2212 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 2213 | { |
907f2784 | 2214 | struct seq_file *m = file->private_data; |
4acd4d00 | 2215 | struct trace_iterator *iter; |
3928a8a2 | 2216 | int cpu; |
bc0c38d1 | 2217 | |
4acd4d00 SR |
2218 | if (!(file->f_mode & FMODE_READ)) |
2219 | return 0; | |
2220 | ||
2221 | iter = m->private; | |
2222 | ||
bc0c38d1 | 2223 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
2224 | for_each_tracing_cpu(cpu) { |
2225 | if (iter->buffer_iter[cpu]) | |
2226 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2227 | } | |
2228 | ||
bc0c38d1 SR |
2229 | if (iter->trace && iter->trace->close) |
2230 | iter->trace->close(iter); | |
2231 | ||
2232 | /* reenable tracing if it was previously enabled */ | |
9036990d | 2233 | tracing_start(); |
bc0c38d1 SR |
2234 | mutex_unlock(&trace_types_lock); |
2235 | ||
2236 | seq_release(inode, file); | |
d7350c3f | 2237 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2238 | free_cpumask_var(iter->started); |
d7350c3f | 2239 | kfree(iter->trace); |
bc0c38d1 SR |
2240 | kfree(iter); |
2241 | return 0; | |
2242 | } | |
2243 | ||
2244 | static int tracing_open(struct inode *inode, struct file *file) | |
2245 | { | |
85a2f9b4 SR |
2246 | struct trace_iterator *iter; |
2247 | int ret = 0; | |
bc0c38d1 | 2248 | |
4acd4d00 SR |
2249 | /* If this file was open for write, then erase contents */ |
2250 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2251 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 2252 | long cpu = (long) inode->i_private; |
bc0c38d1 | 2253 | |
4acd4d00 SR |
2254 | if (cpu == TRACE_PIPE_ALL_CPU) |
2255 | tracing_reset_online_cpus(&global_trace); | |
2256 | else | |
2257 | tracing_reset(&global_trace, cpu); | |
2258 | } | |
bc0c38d1 | 2259 | |
4acd4d00 SR |
2260 | if (file->f_mode & FMODE_READ) { |
2261 | iter = __tracing_open(inode, file); | |
2262 | if (IS_ERR(iter)) | |
2263 | ret = PTR_ERR(iter); | |
2264 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2265 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2266 | } | |
bc0c38d1 SR |
2267 | return ret; |
2268 | } | |
2269 | ||
e309b41d | 2270 | static void * |
bc0c38d1 SR |
2271 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2272 | { | |
f129e965 | 2273 | struct tracer *t = v; |
bc0c38d1 SR |
2274 | |
2275 | (*pos)++; | |
2276 | ||
2277 | if (t) | |
2278 | t = t->next; | |
2279 | ||
bc0c38d1 SR |
2280 | return t; |
2281 | } | |
2282 | ||
2283 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2284 | { | |
f129e965 | 2285 | struct tracer *t; |
bc0c38d1 SR |
2286 | loff_t l = 0; |
2287 | ||
2288 | mutex_lock(&trace_types_lock); | |
f129e965 | 2289 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2290 | ; |
2291 | ||
2292 | return t; | |
2293 | } | |
2294 | ||
2295 | static void t_stop(struct seq_file *m, void *p) | |
2296 | { | |
2297 | mutex_unlock(&trace_types_lock); | |
2298 | } | |
2299 | ||
2300 | static int t_show(struct seq_file *m, void *v) | |
2301 | { | |
2302 | struct tracer *t = v; | |
2303 | ||
2304 | if (!t) | |
2305 | return 0; | |
2306 | ||
2307 | seq_printf(m, "%s", t->name); | |
2308 | if (t->next) | |
2309 | seq_putc(m, ' '); | |
2310 | else | |
2311 | seq_putc(m, '\n'); | |
2312 | ||
2313 | return 0; | |
2314 | } | |
2315 | ||
88e9d34c | 2316 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
2317 | .start = t_start, |
2318 | .next = t_next, | |
2319 | .stop = t_stop, | |
2320 | .show = t_show, | |
bc0c38d1 SR |
2321 | }; |
2322 | ||
2323 | static int show_traces_open(struct inode *inode, struct file *file) | |
2324 | { | |
60a11774 SR |
2325 | if (tracing_disabled) |
2326 | return -ENODEV; | |
2327 | ||
f129e965 | 2328 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2329 | } |
2330 | ||
4acd4d00 SR |
2331 | static ssize_t |
2332 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2333 | size_t count, loff_t *ppos) | |
2334 | { | |
2335 | return count; | |
2336 | } | |
2337 | ||
364829b1 SP |
2338 | static loff_t tracing_seek(struct file *file, loff_t offset, int origin) |
2339 | { | |
2340 | if (file->f_mode & FMODE_READ) | |
2341 | return seq_lseek(file, offset, origin); | |
2342 | else | |
2343 | return 0; | |
2344 | } | |
2345 | ||
5e2336a0 | 2346 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2347 | .open = tracing_open, |
2348 | .read = seq_read, | |
4acd4d00 | 2349 | .write = tracing_write_stub, |
364829b1 | 2350 | .llseek = tracing_seek, |
4bf39a94 | 2351 | .release = tracing_release, |
bc0c38d1 SR |
2352 | }; |
2353 | ||
5e2336a0 | 2354 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2355 | .open = show_traces_open, |
2356 | .read = seq_read, | |
2357 | .release = seq_release, | |
b444786f | 2358 | .llseek = seq_lseek, |
c7078de1 IM |
2359 | }; |
2360 | ||
36dfe925 IM |
2361 | /* |
2362 | * Only trace on a CPU if the bitmask is set: | |
2363 | */ | |
9e01c1b7 | 2364 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2365 | |
2366 | /* | |
2367 | * The tracer itself will not take this lock, but still we want | |
2368 | * to provide a consistent cpumask to user-space: | |
2369 | */ | |
2370 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2371 | ||
2372 | /* | |
2373 | * Temporary storage for the character representation of the | |
2374 | * CPU bitmask (and one more byte for the newline): | |
2375 | */ | |
2376 | static char mask_str[NR_CPUS + 1]; | |
2377 | ||
c7078de1 IM |
2378 | static ssize_t |
2379 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2380 | size_t count, loff_t *ppos) | |
2381 | { | |
36dfe925 | 2382 | int len; |
c7078de1 IM |
2383 | |
2384 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2385 | |
9e01c1b7 | 2386 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2387 | if (count - len < 2) { |
2388 | count = -EINVAL; | |
2389 | goto out_err; | |
2390 | } | |
2391 | len += sprintf(mask_str + len, "\n"); | |
2392 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2393 | ||
2394 | out_err: | |
c7078de1 IM |
2395 | mutex_unlock(&tracing_cpumask_update_lock); |
2396 | ||
2397 | return count; | |
2398 | } | |
2399 | ||
2400 | static ssize_t | |
2401 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2402 | size_t count, loff_t *ppos) | |
2403 | { | |
36dfe925 | 2404 | int err, cpu; |
9e01c1b7 RR |
2405 | cpumask_var_t tracing_cpumask_new; |
2406 | ||
2407 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2408 | return -ENOMEM; | |
c7078de1 | 2409 | |
9e01c1b7 | 2410 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2411 | if (err) |
36dfe925 IM |
2412 | goto err_unlock; |
2413 | ||
215368e8 LZ |
2414 | mutex_lock(&tracing_cpumask_update_lock); |
2415 | ||
a5e25883 | 2416 | local_irq_disable(); |
0199c4e6 | 2417 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 2418 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2419 | /* |
2420 | * Increase/decrease the disabled counter if we are | |
2421 | * about to flip a bit in the cpumask: | |
2422 | */ | |
9e01c1b7 RR |
2423 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2424 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2425 | atomic_inc(&global_trace.data[cpu]->disabled); |
2426 | } | |
9e01c1b7 RR |
2427 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2428 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2429 | atomic_dec(&global_trace.data[cpu]->disabled); |
2430 | } | |
2431 | } | |
0199c4e6 | 2432 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2433 | local_irq_enable(); |
36dfe925 | 2434 | |
9e01c1b7 | 2435 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2436 | |
2437 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2438 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2439 | |
2440 | return count; | |
36dfe925 IM |
2441 | |
2442 | err_unlock: | |
215368e8 | 2443 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2444 | |
2445 | return err; | |
c7078de1 IM |
2446 | } |
2447 | ||
5e2336a0 | 2448 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2449 | .open = tracing_open_generic, |
2450 | .read = tracing_cpumask_read, | |
2451 | .write = tracing_cpumask_write, | |
b444786f | 2452 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
2453 | }; |
2454 | ||
fdb372ed | 2455 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 2456 | { |
d8e83d26 SR |
2457 | struct tracer_opt *trace_opts; |
2458 | u32 tracer_flags; | |
d8e83d26 | 2459 | int i; |
adf9f195 | 2460 | |
d8e83d26 SR |
2461 | mutex_lock(&trace_types_lock); |
2462 | tracer_flags = current_trace->flags->val; | |
2463 | trace_opts = current_trace->flags->opts; | |
2464 | ||
bc0c38d1 SR |
2465 | for (i = 0; trace_options[i]; i++) { |
2466 | if (trace_flags & (1 << i)) | |
fdb372ed | 2467 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 2468 | else |
fdb372ed | 2469 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2470 | } |
2471 | ||
adf9f195 FW |
2472 | for (i = 0; trace_opts[i].name; i++) { |
2473 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 2474 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 2475 | else |
fdb372ed | 2476 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 2477 | } |
d8e83d26 | 2478 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2479 | |
fdb372ed | 2480 | return 0; |
bc0c38d1 | 2481 | } |
bc0c38d1 | 2482 | |
8d18eaaf LZ |
2483 | static int __set_tracer_option(struct tracer *trace, |
2484 | struct tracer_flags *tracer_flags, | |
2485 | struct tracer_opt *opts, int neg) | |
2486 | { | |
2487 | int ret; | |
bc0c38d1 | 2488 | |
8d18eaaf LZ |
2489 | ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); |
2490 | if (ret) | |
2491 | return ret; | |
2492 | ||
2493 | if (neg) | |
2494 | tracer_flags->val &= ~opts->bit; | |
2495 | else | |
2496 | tracer_flags->val |= opts->bit; | |
2497 | return 0; | |
bc0c38d1 SR |
2498 | } |
2499 | ||
adf9f195 FW |
2500 | /* Try to assign a tracer specific option */ |
2501 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2502 | { | |
7770841e | 2503 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 2504 | struct tracer_opt *opts = NULL; |
8d18eaaf | 2505 | int i; |
adf9f195 | 2506 | |
7770841e Z |
2507 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2508 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 2509 | |
8d18eaaf LZ |
2510 | if (strcmp(cmp, opts->name) == 0) |
2511 | return __set_tracer_option(trace, trace->flags, | |
2512 | opts, neg); | |
adf9f195 | 2513 | } |
adf9f195 | 2514 | |
8d18eaaf | 2515 | return -EINVAL; |
adf9f195 FW |
2516 | } |
2517 | ||
af4617bd SR |
2518 | static void set_tracer_flags(unsigned int mask, int enabled) |
2519 | { | |
2520 | /* do nothing if flag is already set */ | |
2521 | if (!!(trace_flags & mask) == !!enabled) | |
2522 | return; | |
2523 | ||
2524 | if (enabled) | |
2525 | trace_flags |= mask; | |
2526 | else | |
2527 | trace_flags &= ~mask; | |
e870e9a1 LZ |
2528 | |
2529 | if (mask == TRACE_ITER_RECORD_CMD) | |
2530 | trace_event_enable_cmd_record(enabled); | |
750912fa DS |
2531 | |
2532 | if (mask == TRACE_ITER_OVERWRITE) | |
2533 | ring_buffer_change_overwrite(global_trace.buffer, enabled); | |
af4617bd SR |
2534 | } |
2535 | ||
bc0c38d1 | 2536 | static ssize_t |
ee6bce52 | 2537 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2538 | size_t cnt, loff_t *ppos) |
2539 | { | |
2540 | char buf[64]; | |
8d18eaaf | 2541 | char *cmp; |
bc0c38d1 | 2542 | int neg = 0; |
adf9f195 | 2543 | int ret; |
bc0c38d1 SR |
2544 | int i; |
2545 | ||
cffae437 SR |
2546 | if (cnt >= sizeof(buf)) |
2547 | return -EINVAL; | |
bc0c38d1 SR |
2548 | |
2549 | if (copy_from_user(&buf, ubuf, cnt)) | |
2550 | return -EFAULT; | |
2551 | ||
2552 | buf[cnt] = 0; | |
8d18eaaf | 2553 | cmp = strstrip(buf); |
bc0c38d1 | 2554 | |
8d18eaaf | 2555 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
2556 | neg = 1; |
2557 | cmp += 2; | |
2558 | } | |
2559 | ||
2560 | for (i = 0; trace_options[i]; i++) { | |
8d18eaaf | 2561 | if (strcmp(cmp, trace_options[i]) == 0) { |
af4617bd | 2562 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2563 | break; |
2564 | } | |
2565 | } | |
adf9f195 FW |
2566 | |
2567 | /* If no option could be set, test the specific tracer options */ | |
2568 | if (!trace_options[i]) { | |
d8e83d26 | 2569 | mutex_lock(&trace_types_lock); |
adf9f195 | 2570 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2571 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2572 | if (ret) |
2573 | return ret; | |
2574 | } | |
bc0c38d1 | 2575 | |
cf8517cf | 2576 | *ppos += cnt; |
bc0c38d1 SR |
2577 | |
2578 | return cnt; | |
2579 | } | |
2580 | ||
fdb372ed LZ |
2581 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
2582 | { | |
2583 | if (tracing_disabled) | |
2584 | return -ENODEV; | |
2585 | return single_open(file, tracing_trace_options_show, NULL); | |
2586 | } | |
2587 | ||
5e2336a0 | 2588 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
2589 | .open = tracing_trace_options_open, |
2590 | .read = seq_read, | |
2591 | .llseek = seq_lseek, | |
2592 | .release = single_release, | |
ee6bce52 | 2593 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
2594 | }; |
2595 | ||
7bd2f24c IM |
2596 | static const char readme_msg[] = |
2597 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2598 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2599 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
bc2b6871 | 2600 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
156f5a78 | 2601 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2602 | "nop\n" |
156f5a78 GL |
2603 | "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" |
2604 | "# cat /sys/kernel/debug/tracing/current_tracer\n" | |
7bd2f24c | 2605 | "sched_switch\n" |
156f5a78 | 2606 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2607 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 GL |
2608 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
2609 | "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
2610 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" | |
2611 | "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
7bd2f24c IM |
2612 | ; |
2613 | ||
2614 | static ssize_t | |
2615 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2616 | size_t cnt, loff_t *ppos) | |
2617 | { | |
2618 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2619 | readme_msg, strlen(readme_msg)); | |
2620 | } | |
2621 | ||
5e2336a0 | 2622 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2623 | .open = tracing_open_generic, |
2624 | .read = tracing_readme_read, | |
b444786f | 2625 | .llseek = generic_file_llseek, |
7bd2f24c IM |
2626 | }; |
2627 | ||
69abe6a5 AP |
2628 | static ssize_t |
2629 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2630 | size_t cnt, loff_t *ppos) | |
2631 | { | |
2632 | char *buf_comm; | |
2633 | char *file_buf; | |
2634 | char *buf; | |
2635 | int len = 0; | |
2636 | int pid; | |
2637 | int i; | |
2638 | ||
2639 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2640 | if (!file_buf) | |
2641 | return -ENOMEM; | |
2642 | ||
2643 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2644 | if (!buf_comm) { | |
2645 | kfree(file_buf); | |
2646 | return -ENOMEM; | |
2647 | } | |
2648 | ||
2649 | buf = file_buf; | |
2650 | ||
2651 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2652 | int r; | |
2653 | ||
2654 | pid = map_cmdline_to_pid[i]; | |
2655 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2656 | continue; | |
2657 | ||
2658 | trace_find_cmdline(pid, buf_comm); | |
2659 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2660 | buf += r; | |
2661 | len += r; | |
2662 | } | |
2663 | ||
2664 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2665 | file_buf, len); | |
2666 | ||
2667 | kfree(file_buf); | |
2668 | kfree(buf_comm); | |
2669 | ||
2670 | return len; | |
2671 | } | |
2672 | ||
2673 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2674 | .open = tracing_open_generic, | |
2675 | .read = tracing_saved_cmdlines_read, | |
b444786f | 2676 | .llseek = generic_file_llseek, |
69abe6a5 AP |
2677 | }; |
2678 | ||
bc0c38d1 SR |
2679 | static ssize_t |
2680 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2681 | size_t cnt, loff_t *ppos) | |
2682 | { | |
bc0c38d1 SR |
2683 | char buf[64]; |
2684 | int r; | |
2685 | ||
9036990d | 2686 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2687 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2688 | } |
2689 | ||
2690 | static ssize_t | |
2691 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2692 | size_t cnt, loff_t *ppos) | |
2693 | { | |
2694 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2695 | char buf[64]; |
5e39841c | 2696 | unsigned long val; |
c6caeeb1 | 2697 | int ret; |
bc0c38d1 | 2698 | |
cffae437 SR |
2699 | if (cnt >= sizeof(buf)) |
2700 | return -EINVAL; | |
bc0c38d1 SR |
2701 | |
2702 | if (copy_from_user(&buf, ubuf, cnt)) | |
2703 | return -EFAULT; | |
2704 | ||
2705 | buf[cnt] = 0; | |
2706 | ||
c6caeeb1 SR |
2707 | ret = strict_strtoul(buf, 10, &val); |
2708 | if (ret < 0) | |
2709 | return ret; | |
bc0c38d1 SR |
2710 | |
2711 | val = !!val; | |
2712 | ||
2713 | mutex_lock(&trace_types_lock); | |
9036990d | 2714 | if (tracer_enabled ^ val) { |
6752ab4a SR |
2715 | |
2716 | /* Only need to warn if this is used to change the state */ | |
2717 | WARN_ONCE(1, "tracing_enabled is deprecated. Use tracing_on"); | |
2718 | ||
9036990d | 2719 | if (val) { |
bc0c38d1 | 2720 | tracer_enabled = 1; |
9036990d SR |
2721 | if (current_trace->start) |
2722 | current_trace->start(tr); | |
2723 | tracing_start(); | |
2724 | } else { | |
bc0c38d1 | 2725 | tracer_enabled = 0; |
9036990d SR |
2726 | tracing_stop(); |
2727 | if (current_trace->stop) | |
2728 | current_trace->stop(tr); | |
2729 | } | |
bc0c38d1 SR |
2730 | } |
2731 | mutex_unlock(&trace_types_lock); | |
2732 | ||
cf8517cf | 2733 | *ppos += cnt; |
bc0c38d1 SR |
2734 | |
2735 | return cnt; | |
2736 | } | |
2737 | ||
2738 | static ssize_t | |
2739 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2740 | size_t cnt, loff_t *ppos) | |
2741 | { | |
ee6c2c1b | 2742 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
2743 | int r; |
2744 | ||
2745 | mutex_lock(&trace_types_lock); | |
2746 | if (current_trace) | |
2747 | r = sprintf(buf, "%s\n", current_trace->name); | |
2748 | else | |
2749 | r = sprintf(buf, "\n"); | |
2750 | mutex_unlock(&trace_types_lock); | |
2751 | ||
4bf39a94 | 2752 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2753 | } |
2754 | ||
b6f11df2 ACM |
2755 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2756 | { | |
2757 | tracing_reset_online_cpus(tr); | |
2758 | return t->init(tr); | |
2759 | } | |
2760 | ||
73c5162a SR |
2761 | static int tracing_resize_ring_buffer(unsigned long size) |
2762 | { | |
2763 | int ret; | |
2764 | ||
2765 | /* | |
2766 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2767 | * we use the size that was given, and we can forget about |
2768 | * expanding it later. | |
73c5162a SR |
2769 | */ |
2770 | ring_buffer_expanded = 1; | |
2771 | ||
2772 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2773 | if (ret < 0) | |
2774 | return ret; | |
2775 | ||
ef710e10 KM |
2776 | if (!current_trace->use_max_tr) |
2777 | goto out; | |
2778 | ||
73c5162a SR |
2779 | ret = ring_buffer_resize(max_tr.buffer, size); |
2780 | if (ret < 0) { | |
2781 | int r; | |
2782 | ||
2783 | r = ring_buffer_resize(global_trace.buffer, | |
2784 | global_trace.entries); | |
2785 | if (r < 0) { | |
a123c52b SR |
2786 | /* |
2787 | * AARGH! We are left with different | |
2788 | * size max buffer!!!! | |
2789 | * The max buffer is our "snapshot" buffer. | |
2790 | * When a tracer needs a snapshot (one of the | |
2791 | * latency tracers), it swaps the max buffer | |
2792 | * with the saved snap shot. We succeeded to | |
2793 | * update the size of the main buffer, but failed to | |
2794 | * update the size of the max buffer. But when we tried | |
2795 | * to reset the main buffer to the original size, we | |
2796 | * failed there too. This is very unlikely to | |
2797 | * happen, but if it does, warn and kill all | |
2798 | * tracing. | |
2799 | */ | |
73c5162a SR |
2800 | WARN_ON(1); |
2801 | tracing_disabled = 1; | |
2802 | } | |
2803 | return ret; | |
2804 | } | |
2805 | ||
ef710e10 KM |
2806 | max_tr.entries = size; |
2807 | out: | |
73c5162a SR |
2808 | global_trace.entries = size; |
2809 | ||
2810 | return ret; | |
2811 | } | |
2812 | ||
ef710e10 | 2813 | |
1852fcce SR |
2814 | /** |
2815 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2816 | * | |
2817 | * To save on memory when the tracing is never used on a system with it | |
2818 | * configured in. The ring buffers are set to a minimum size. But once | |
2819 | * a user starts to use the tracing facility, then they need to grow | |
2820 | * to their default size. | |
2821 | * | |
2822 | * This function is to be called when a tracer is about to be used. | |
2823 | */ | |
2824 | int tracing_update_buffers(void) | |
2825 | { | |
2826 | int ret = 0; | |
2827 | ||
1027fcb2 | 2828 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2829 | if (!ring_buffer_expanded) |
2830 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2831 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2832 | |
2833 | return ret; | |
2834 | } | |
2835 | ||
577b785f SR |
2836 | struct trace_option_dentry; |
2837 | ||
2838 | static struct trace_option_dentry * | |
2839 | create_trace_option_files(struct tracer *tracer); | |
2840 | ||
2841 | static void | |
2842 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2843 | ||
b2821ae6 | 2844 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2845 | { |
577b785f | 2846 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2847 | struct trace_array *tr = &global_trace; |
2848 | struct tracer *t; | |
d9e54076 | 2849 | int ret = 0; |
bc0c38d1 | 2850 | |
1027fcb2 SR |
2851 | mutex_lock(&trace_types_lock); |
2852 | ||
73c5162a SR |
2853 | if (!ring_buffer_expanded) { |
2854 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2855 | if (ret < 0) | |
59f586db | 2856 | goto out; |
73c5162a SR |
2857 | ret = 0; |
2858 | } | |
2859 | ||
bc0c38d1 SR |
2860 | for (t = trace_types; t; t = t->next) { |
2861 | if (strcmp(t->name, buf) == 0) | |
2862 | break; | |
2863 | } | |
c2931e05 FW |
2864 | if (!t) { |
2865 | ret = -EINVAL; | |
2866 | goto out; | |
2867 | } | |
2868 | if (t == current_trace) | |
bc0c38d1 SR |
2869 | goto out; |
2870 | ||
9f029e83 | 2871 | trace_branch_disable(); |
bc0c38d1 SR |
2872 | if (current_trace && current_trace->reset) |
2873 | current_trace->reset(tr); | |
ef710e10 KM |
2874 | if (current_trace && current_trace->use_max_tr) { |
2875 | /* | |
2876 | * We don't free the ring buffer. instead, resize it because | |
2877 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
2878 | * we want preserve it. | |
2879 | */ | |
2880 | ring_buffer_resize(max_tr.buffer, 1); | |
2881 | max_tr.entries = 1; | |
2882 | } | |
577b785f SR |
2883 | destroy_trace_option_files(topts); |
2884 | ||
bc0c38d1 | 2885 | current_trace = t; |
577b785f SR |
2886 | |
2887 | topts = create_trace_option_files(current_trace); | |
ef710e10 KM |
2888 | if (current_trace->use_max_tr) { |
2889 | ret = ring_buffer_resize(max_tr.buffer, global_trace.entries); | |
2890 | if (ret < 0) | |
2891 | goto out; | |
2892 | max_tr.entries = global_trace.entries; | |
2893 | } | |
577b785f | 2894 | |
1c80025a | 2895 | if (t->init) { |
b6f11df2 | 2896 | ret = tracer_init(t, tr); |
1c80025a FW |
2897 | if (ret) |
2898 | goto out; | |
2899 | } | |
bc0c38d1 | 2900 | |
9f029e83 | 2901 | trace_branch_enable(tr); |
bc0c38d1 SR |
2902 | out: |
2903 | mutex_unlock(&trace_types_lock); | |
2904 | ||
d9e54076 PZ |
2905 | return ret; |
2906 | } | |
2907 | ||
2908 | static ssize_t | |
2909 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2910 | size_t cnt, loff_t *ppos) | |
2911 | { | |
ee6c2c1b | 2912 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
2913 | int i; |
2914 | size_t ret; | |
e6e7a65a FW |
2915 | int err; |
2916 | ||
2917 | ret = cnt; | |
d9e54076 | 2918 | |
ee6c2c1b LZ |
2919 | if (cnt > MAX_TRACER_SIZE) |
2920 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
2921 | |
2922 | if (copy_from_user(&buf, ubuf, cnt)) | |
2923 | return -EFAULT; | |
2924 | ||
2925 | buf[cnt] = 0; | |
2926 | ||
2927 | /* strip ending whitespace. */ | |
2928 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2929 | buf[i] = 0; | |
2930 | ||
e6e7a65a FW |
2931 | err = tracing_set_tracer(buf); |
2932 | if (err) | |
2933 | return err; | |
d9e54076 | 2934 | |
cf8517cf | 2935 | *ppos += ret; |
bc0c38d1 | 2936 | |
c2931e05 | 2937 | return ret; |
bc0c38d1 SR |
2938 | } |
2939 | ||
2940 | static ssize_t | |
2941 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2942 | size_t cnt, loff_t *ppos) | |
2943 | { | |
2944 | unsigned long *ptr = filp->private_data; | |
2945 | char buf[64]; | |
2946 | int r; | |
2947 | ||
cffae437 | 2948 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2949 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2950 | if (r > sizeof(buf)) |
2951 | r = sizeof(buf); | |
4bf39a94 | 2952 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2953 | } |
2954 | ||
2955 | static ssize_t | |
2956 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2957 | size_t cnt, loff_t *ppos) | |
2958 | { | |
5e39841c | 2959 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2960 | char buf[64]; |
5e39841c | 2961 | unsigned long val; |
c6caeeb1 | 2962 | int ret; |
bc0c38d1 | 2963 | |
cffae437 SR |
2964 | if (cnt >= sizeof(buf)) |
2965 | return -EINVAL; | |
bc0c38d1 SR |
2966 | |
2967 | if (copy_from_user(&buf, ubuf, cnt)) | |
2968 | return -EFAULT; | |
2969 | ||
2970 | buf[cnt] = 0; | |
2971 | ||
c6caeeb1 SR |
2972 | ret = strict_strtoul(buf, 10, &val); |
2973 | if (ret < 0) | |
2974 | return ret; | |
bc0c38d1 SR |
2975 | |
2976 | *ptr = val * 1000; | |
2977 | ||
2978 | return cnt; | |
2979 | } | |
2980 | ||
b3806b43 SR |
2981 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2982 | { | |
b04cc6b1 | 2983 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2984 | struct trace_iterator *iter; |
b04cc6b1 | 2985 | int ret = 0; |
b3806b43 SR |
2986 | |
2987 | if (tracing_disabled) | |
2988 | return -ENODEV; | |
2989 | ||
b04cc6b1 FW |
2990 | mutex_lock(&trace_types_lock); |
2991 | ||
b3806b43 SR |
2992 | /* create a buffer to store the information to pass to userspace */ |
2993 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2994 | if (!iter) { |
2995 | ret = -ENOMEM; | |
2996 | goto out; | |
2997 | } | |
b3806b43 | 2998 | |
d7350c3f FW |
2999 | /* |
3000 | * We make a copy of the current tracer to avoid concurrent | |
3001 | * changes on it while we are reading. | |
3002 | */ | |
3003 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
3004 | if (!iter->trace) { | |
3005 | ret = -ENOMEM; | |
3006 | goto fail; | |
3007 | } | |
3008 | if (current_trace) | |
3009 | *iter->trace = *current_trace; | |
3010 | ||
4462344e | 3011 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 3012 | ret = -ENOMEM; |
d7350c3f | 3013 | goto fail; |
4462344e RR |
3014 | } |
3015 | ||
a309720c | 3016 | /* trace pipe does not show start of buffer */ |
4462344e | 3017 | cpumask_setall(iter->started); |
a309720c | 3018 | |
112f38a7 SR |
3019 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
3020 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3021 | ||
b04cc6b1 | 3022 | iter->cpu_file = cpu_file; |
b3806b43 | 3023 | iter->tr = &global_trace; |
d7350c3f | 3024 | mutex_init(&iter->mutex); |
b3806b43 SR |
3025 | filp->private_data = iter; |
3026 | ||
107bad8b SR |
3027 | if (iter->trace->pipe_open) |
3028 | iter->trace->pipe_open(iter); | |
107bad8b | 3029 | |
b444786f | 3030 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
3031 | out: |
3032 | mutex_unlock(&trace_types_lock); | |
3033 | return ret; | |
d7350c3f FW |
3034 | |
3035 | fail: | |
3036 | kfree(iter->trace); | |
3037 | kfree(iter); | |
3038 | mutex_unlock(&trace_types_lock); | |
3039 | return ret; | |
b3806b43 SR |
3040 | } |
3041 | ||
3042 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
3043 | { | |
3044 | struct trace_iterator *iter = file->private_data; | |
3045 | ||
b04cc6b1 FW |
3046 | mutex_lock(&trace_types_lock); |
3047 | ||
29bf4a5e | 3048 | if (iter->trace->pipe_close) |
c521efd1 SR |
3049 | iter->trace->pipe_close(iter); |
3050 | ||
b04cc6b1 FW |
3051 | mutex_unlock(&trace_types_lock); |
3052 | ||
4462344e | 3053 | free_cpumask_var(iter->started); |
d7350c3f FW |
3054 | mutex_destroy(&iter->mutex); |
3055 | kfree(iter->trace); | |
b3806b43 | 3056 | kfree(iter); |
b3806b43 SR |
3057 | |
3058 | return 0; | |
3059 | } | |
3060 | ||
2a2cc8f7 SSP |
3061 | static unsigned int |
3062 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
3063 | { | |
3064 | struct trace_iterator *iter = filp->private_data; | |
3065 | ||
3066 | if (trace_flags & TRACE_ITER_BLOCK) { | |
3067 | /* | |
3068 | * Always select as readable when in blocking mode | |
3069 | */ | |
3070 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 3071 | } else { |
2a2cc8f7 SSP |
3072 | if (!trace_empty(iter)) |
3073 | return POLLIN | POLLRDNORM; | |
3074 | poll_wait(filp, &trace_wait, poll_table); | |
3075 | if (!trace_empty(iter)) | |
3076 | return POLLIN | POLLRDNORM; | |
3077 | ||
3078 | return 0; | |
3079 | } | |
3080 | } | |
3081 | ||
6eaaa5d5 FW |
3082 | |
3083 | void default_wait_pipe(struct trace_iterator *iter) | |
3084 | { | |
3085 | DEFINE_WAIT(wait); | |
3086 | ||
3087 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
3088 | ||
3089 | if (trace_empty(iter)) | |
3090 | schedule(); | |
3091 | ||
3092 | finish_wait(&trace_wait, &wait); | |
3093 | } | |
3094 | ||
3095 | /* | |
3096 | * This is a make-shift waitqueue. | |
3097 | * A tracer might use this callback on some rare cases: | |
3098 | * | |
3099 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
3100 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
3101 | * 2) the function tracers, trace all functions, we don't want | |
3102 | * the overhead of calling wake_up and friends | |
3103 | * (and tracing them too) | |
3104 | * | |
3105 | * Anyway, this is really very primitive wakeup. | |
3106 | */ | |
3107 | void poll_wait_pipe(struct trace_iterator *iter) | |
3108 | { | |
3109 | set_current_state(TASK_INTERRUPTIBLE); | |
3110 | /* sleep for 100 msecs, and try again. */ | |
3111 | schedule_timeout(HZ / 10); | |
3112 | } | |
3113 | ||
ff98781b EGM |
3114 | /* Must be called with trace_types_lock mutex held. */ |
3115 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
3116 | { |
3117 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 3118 | |
b3806b43 | 3119 | while (trace_empty(iter)) { |
2dc8f095 | 3120 | |
107bad8b | 3121 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 3122 | return -EAGAIN; |
107bad8b | 3123 | } |
2dc8f095 | 3124 | |
d7350c3f | 3125 | mutex_unlock(&iter->mutex); |
107bad8b | 3126 | |
6eaaa5d5 | 3127 | iter->trace->wait_pipe(iter); |
b3806b43 | 3128 | |
d7350c3f | 3129 | mutex_lock(&iter->mutex); |
107bad8b | 3130 | |
6eaaa5d5 | 3131 | if (signal_pending(current)) |
ff98781b | 3132 | return -EINTR; |
b3806b43 SR |
3133 | |
3134 | /* | |
3135 | * We block until we read something and tracing is disabled. | |
3136 | * We still block if tracing is disabled, but we have never | |
3137 | * read anything. This allows a user to cat this file, and | |
3138 | * then enable tracing. But after we have read something, | |
3139 | * we give an EOF when tracing is again disabled. | |
3140 | * | |
3141 | * iter->pos will be 0 if we haven't read anything. | |
3142 | */ | |
3143 | if (!tracer_enabled && iter->pos) | |
3144 | break; | |
b3806b43 SR |
3145 | } |
3146 | ||
ff98781b EGM |
3147 | return 1; |
3148 | } | |
3149 | ||
3150 | /* | |
3151 | * Consumer reader. | |
3152 | */ | |
3153 | static ssize_t | |
3154 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
3155 | size_t cnt, loff_t *ppos) | |
3156 | { | |
3157 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 3158 | static struct tracer *old_tracer; |
ff98781b EGM |
3159 | ssize_t sret; |
3160 | ||
3161 | /* return any leftover data */ | |
3162 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
3163 | if (sret != -EBUSY) | |
3164 | return sret; | |
3165 | ||
f9520750 | 3166 | trace_seq_init(&iter->seq); |
ff98781b | 3167 | |
d7350c3f | 3168 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 3169 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3170 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3171 | old_tracer = current_trace; | |
3172 | *iter->trace = *current_trace; | |
3173 | } | |
3174 | mutex_unlock(&trace_types_lock); | |
3175 | ||
3176 | /* | |
3177 | * Avoid more than one consumer on a single file descriptor | |
3178 | * This is just a matter of traces coherency, the ring buffer itself | |
3179 | * is protected. | |
3180 | */ | |
3181 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
3182 | if (iter->trace->read) { |
3183 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
3184 | if (sret) | |
3185 | goto out; | |
3186 | } | |
3187 | ||
3188 | waitagain: | |
3189 | sret = tracing_wait_pipe(filp); | |
3190 | if (sret <= 0) | |
3191 | goto out; | |
3192 | ||
b3806b43 | 3193 | /* stop when tracing is finished */ |
ff98781b EGM |
3194 | if (trace_empty(iter)) { |
3195 | sret = 0; | |
107bad8b | 3196 | goto out; |
ff98781b | 3197 | } |
b3806b43 SR |
3198 | |
3199 | if (cnt >= PAGE_SIZE) | |
3200 | cnt = PAGE_SIZE - 1; | |
3201 | ||
53d0aa77 | 3202 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
3203 | memset(&iter->seq, 0, |
3204 | sizeof(struct trace_iterator) - | |
3205 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 3206 | iter->pos = -1; |
b3806b43 | 3207 | |
4f535968 | 3208 | trace_event_read_lock(); |
7e53bd42 | 3209 | trace_access_lock(iter->cpu_file); |
955b61e5 | 3210 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 3211 | enum print_line_t ret; |
088b1e42 SR |
3212 | int len = iter->seq.len; |
3213 | ||
f9896bf3 | 3214 | ret = print_trace_line(iter); |
2c4f035f | 3215 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
3216 | /* don't print partial lines */ |
3217 | iter->seq.len = len; | |
b3806b43 | 3218 | break; |
088b1e42 | 3219 | } |
b91facc3 FW |
3220 | if (ret != TRACE_TYPE_NO_CONSUME) |
3221 | trace_consume(iter); | |
b3806b43 SR |
3222 | |
3223 | if (iter->seq.len >= cnt) | |
3224 | break; | |
b3806b43 | 3225 | } |
7e53bd42 | 3226 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3227 | trace_event_read_unlock(); |
b3806b43 | 3228 | |
b3806b43 | 3229 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3230 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3231 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3232 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3233 | |
3234 | /* | |
3235 | * If there was nothing to send to user, inspite of consuming trace | |
3236 | * entries, go back to wait for more entries. | |
3237 | */ | |
6c6c2796 | 3238 | if (sret == -EBUSY) |
9ff4b974 | 3239 | goto waitagain; |
b3806b43 | 3240 | |
107bad8b | 3241 | out: |
d7350c3f | 3242 | mutex_unlock(&iter->mutex); |
107bad8b | 3243 | |
6c6c2796 | 3244 | return sret; |
b3806b43 SR |
3245 | } |
3246 | ||
3c56819b EGM |
3247 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3248 | struct pipe_buffer *buf) | |
3249 | { | |
3250 | __free_page(buf->page); | |
3251 | } | |
3252 | ||
3253 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3254 | unsigned int idx) | |
3255 | { | |
3256 | __free_page(spd->pages[idx]); | |
3257 | } | |
3258 | ||
28dfef8f | 3259 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
3260 | .can_merge = 0, |
3261 | .map = generic_pipe_buf_map, | |
3262 | .unmap = generic_pipe_buf_unmap, | |
3263 | .confirm = generic_pipe_buf_confirm, | |
3264 | .release = tracing_pipe_buf_release, | |
3265 | .steal = generic_pipe_buf_steal, | |
3266 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3267 | }; |
3268 | ||
34cd4998 | 3269 | static size_t |
fa7c7f6e | 3270 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3271 | { |
3272 | size_t count; | |
3273 | int ret; | |
3274 | ||
3275 | /* Seq buffer is page-sized, exactly what we need. */ | |
3276 | for (;;) { | |
3277 | count = iter->seq.len; | |
3278 | ret = print_trace_line(iter); | |
3279 | count = iter->seq.len - count; | |
3280 | if (rem < count) { | |
3281 | rem = 0; | |
3282 | iter->seq.len -= count; | |
3283 | break; | |
3284 | } | |
3285 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3286 | iter->seq.len -= count; | |
3287 | break; | |
3288 | } | |
3289 | ||
74e7ff8c LJ |
3290 | if (ret != TRACE_TYPE_NO_CONSUME) |
3291 | trace_consume(iter); | |
34cd4998 | 3292 | rem -= count; |
955b61e5 | 3293 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
3294 | rem = 0; |
3295 | iter->ent = NULL; | |
3296 | break; | |
3297 | } | |
3298 | } | |
3299 | ||
3300 | return rem; | |
3301 | } | |
3302 | ||
3c56819b EGM |
3303 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3304 | loff_t *ppos, | |
3305 | struct pipe_inode_info *pipe, | |
3306 | size_t len, | |
3307 | unsigned int flags) | |
3308 | { | |
35f3d14d JA |
3309 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
3310 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
3311 | struct trace_iterator *iter = filp->private_data; |
3312 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
3313 | .pages = pages_def, |
3314 | .partial = partial_def, | |
34cd4998 SR |
3315 | .nr_pages = 0, /* This gets updated below. */ |
3316 | .flags = flags, | |
3317 | .ops = &tracing_pipe_buf_ops, | |
3318 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3319 | }; |
d7350c3f | 3320 | static struct tracer *old_tracer; |
3c56819b | 3321 | ssize_t ret; |
34cd4998 | 3322 | size_t rem; |
3c56819b EGM |
3323 | unsigned int i; |
3324 | ||
35f3d14d JA |
3325 | if (splice_grow_spd(pipe, &spd)) |
3326 | return -ENOMEM; | |
3327 | ||
d7350c3f | 3328 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3329 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3330 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3331 | old_tracer = current_trace; | |
3332 | *iter->trace = *current_trace; | |
3333 | } | |
3334 | mutex_unlock(&trace_types_lock); | |
3335 | ||
3336 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3337 | |
3338 | if (iter->trace->splice_read) { | |
3339 | ret = iter->trace->splice_read(iter, filp, | |
3340 | ppos, pipe, len, flags); | |
3341 | if (ret) | |
34cd4998 | 3342 | goto out_err; |
3c56819b EGM |
3343 | } |
3344 | ||
3345 | ret = tracing_wait_pipe(filp); | |
3346 | if (ret <= 0) | |
34cd4998 | 3347 | goto out_err; |
3c56819b | 3348 | |
955b61e5 | 3349 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 3350 | ret = -EFAULT; |
34cd4998 | 3351 | goto out_err; |
3c56819b EGM |
3352 | } |
3353 | ||
4f535968 | 3354 | trace_event_read_lock(); |
7e53bd42 | 3355 | trace_access_lock(iter->cpu_file); |
4f535968 | 3356 | |
3c56819b | 3357 | /* Fill as many pages as possible. */ |
35f3d14d JA |
3358 | for (i = 0, rem = len; i < pipe->buffers && rem; i++) { |
3359 | spd.pages[i] = alloc_page(GFP_KERNEL); | |
3360 | if (!spd.pages[i]) | |
34cd4998 | 3361 | break; |
3c56819b | 3362 | |
fa7c7f6e | 3363 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3364 | |
3365 | /* Copy the data into the page, so we can start over. */ | |
3366 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 3367 | page_address(spd.pages[i]), |
3c56819b EGM |
3368 | iter->seq.len); |
3369 | if (ret < 0) { | |
35f3d14d | 3370 | __free_page(spd.pages[i]); |
3c56819b EGM |
3371 | break; |
3372 | } | |
35f3d14d JA |
3373 | spd.partial[i].offset = 0; |
3374 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 3375 | |
f9520750 | 3376 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3377 | } |
3378 | ||
7e53bd42 | 3379 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3380 | trace_event_read_unlock(); |
d7350c3f | 3381 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3382 | |
3383 | spd.nr_pages = i; | |
3384 | ||
35f3d14d JA |
3385 | ret = splice_to_pipe(pipe, &spd); |
3386 | out: | |
3387 | splice_shrink_spd(pipe, &spd); | |
3388 | return ret; | |
3c56819b | 3389 | |
34cd4998 | 3390 | out_err: |
d7350c3f | 3391 | mutex_unlock(&iter->mutex); |
35f3d14d | 3392 | goto out; |
3c56819b EGM |
3393 | } |
3394 | ||
a98a3c3f SR |
3395 | static ssize_t |
3396 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3397 | size_t cnt, loff_t *ppos) | |
3398 | { | |
3399 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3400 | char buf[96]; |
a98a3c3f SR |
3401 | int r; |
3402 | ||
db526ca3 SR |
3403 | mutex_lock(&trace_types_lock); |
3404 | if (!ring_buffer_expanded) | |
3405 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3406 | tr->entries >> 10, | |
3407 | trace_buf_size >> 10); | |
3408 | else | |
3409 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3410 | mutex_unlock(&trace_types_lock); | |
3411 | ||
a98a3c3f SR |
3412 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3413 | } | |
3414 | ||
3415 | static ssize_t | |
3416 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3417 | size_t cnt, loff_t *ppos) | |
3418 | { | |
3419 | unsigned long val; | |
3420 | char buf[64]; | |
bf5e6519 | 3421 | int ret, cpu; |
a98a3c3f | 3422 | |
cffae437 SR |
3423 | if (cnt >= sizeof(buf)) |
3424 | return -EINVAL; | |
a98a3c3f SR |
3425 | |
3426 | if (copy_from_user(&buf, ubuf, cnt)) | |
3427 | return -EFAULT; | |
3428 | ||
3429 | buf[cnt] = 0; | |
3430 | ||
c6caeeb1 SR |
3431 | ret = strict_strtoul(buf, 10, &val); |
3432 | if (ret < 0) | |
3433 | return ret; | |
a98a3c3f SR |
3434 | |
3435 | /* must have at least 1 entry */ | |
3436 | if (!val) | |
3437 | return -EINVAL; | |
3438 | ||
3439 | mutex_lock(&trace_types_lock); | |
3440 | ||
c76f0694 | 3441 | tracing_stop(); |
a98a3c3f | 3442 | |
bf5e6519 SR |
3443 | /* disable all cpu buffers */ |
3444 | for_each_tracing_cpu(cpu) { | |
3445 | if (global_trace.data[cpu]) | |
3446 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3447 | if (max_tr.data[cpu]) | |
3448 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3449 | } | |
3450 | ||
1696b2b0 SR |
3451 | /* value is in KB */ |
3452 | val <<= 10; | |
3453 | ||
3928a8a2 | 3454 | if (val != global_trace.entries) { |
73c5162a | 3455 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3456 | if (ret < 0) { |
3457 | cnt = ret; | |
3eefae99 SR |
3458 | goto out; |
3459 | } | |
a98a3c3f SR |
3460 | } |
3461 | ||
cf8517cf | 3462 | *ppos += cnt; |
a98a3c3f | 3463 | |
19384c03 SR |
3464 | /* If check pages failed, return ENOMEM */ |
3465 | if (tracing_disabled) | |
3466 | cnt = -ENOMEM; | |
a98a3c3f | 3467 | out: |
bf5e6519 SR |
3468 | for_each_tracing_cpu(cpu) { |
3469 | if (global_trace.data[cpu]) | |
3470 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3471 | if (max_tr.data[cpu]) | |
3472 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3473 | } | |
3474 | ||
c76f0694 | 3475 | tracing_start(); |
a98a3c3f SR |
3476 | mutex_unlock(&trace_types_lock); |
3477 | ||
3478 | return cnt; | |
3479 | } | |
3480 | ||
f2942487 CE |
3481 | static int mark_printk(const char *fmt, ...) |
3482 | { | |
3483 | int ret; | |
3484 | va_list args; | |
3485 | va_start(args, fmt); | |
3486 | ret = trace_vprintk(0, fmt, args); | |
3487 | va_end(args); | |
3488 | return ret; | |
3489 | } | |
3490 | ||
5bf9a1ee PP |
3491 | static ssize_t |
3492 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3493 | size_t cnt, loff_t *fpos) | |
3494 | { | |
3495 | char *buf; | |
1aa54bca | 3496 | size_t written; |
5bf9a1ee | 3497 | |
c76f0694 | 3498 | if (tracing_disabled) |
5bf9a1ee PP |
3499 | return -EINVAL; |
3500 | ||
3501 | if (cnt > TRACE_BUF_SIZE) | |
3502 | cnt = TRACE_BUF_SIZE; | |
3503 | ||
c13d2f7c | 3504 | buf = kmalloc(cnt + 2, GFP_KERNEL); |
5bf9a1ee PP |
3505 | if (buf == NULL) |
3506 | return -ENOMEM; | |
3507 | ||
3508 | if (copy_from_user(buf, ubuf, cnt)) { | |
3509 | kfree(buf); | |
3510 | return -EFAULT; | |
3511 | } | |
c13d2f7c CE |
3512 | if (buf[cnt-1] != '\n') { |
3513 | buf[cnt] = '\n'; | |
3514 | buf[cnt+1] = '\0'; | |
3515 | } else | |
3516 | buf[cnt] = '\0'; | |
5bf9a1ee | 3517 | |
1aa54bca | 3518 | written = mark_printk("%s", buf); |
5bf9a1ee | 3519 | kfree(buf); |
1aa54bca | 3520 | *fpos += written; |
5bf9a1ee | 3521 | |
1aa54bca MS |
3522 | /* don't tell userspace we wrote more - it might confuse them */ |
3523 | if (written > cnt) | |
3524 | written = cnt; | |
3525 | ||
3526 | return written; | |
5bf9a1ee PP |
3527 | } |
3528 | ||
13f16d20 | 3529 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 3530 | { |
5079f326 Z |
3531 | int i; |
3532 | ||
3533 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 3534 | seq_printf(m, |
5079f326 Z |
3535 | "%s%s%s%s", i ? " " : "", |
3536 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3537 | i == trace_clock_id ? "]" : ""); | |
13f16d20 | 3538 | seq_putc(m, '\n'); |
5079f326 | 3539 | |
13f16d20 | 3540 | return 0; |
5079f326 Z |
3541 | } |
3542 | ||
3543 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
3544 | size_t cnt, loff_t *fpos) | |
3545 | { | |
3546 | char buf[64]; | |
3547 | const char *clockstr; | |
3548 | int i; | |
3549 | ||
3550 | if (cnt >= sizeof(buf)) | |
3551 | return -EINVAL; | |
3552 | ||
3553 | if (copy_from_user(&buf, ubuf, cnt)) | |
3554 | return -EFAULT; | |
3555 | ||
3556 | buf[cnt] = 0; | |
3557 | ||
3558 | clockstr = strstrip(buf); | |
3559 | ||
3560 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
3561 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
3562 | break; | |
3563 | } | |
3564 | if (i == ARRAY_SIZE(trace_clocks)) | |
3565 | return -EINVAL; | |
3566 | ||
3567 | trace_clock_id = i; | |
3568 | ||
3569 | mutex_lock(&trace_types_lock); | |
3570 | ||
3571 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
3572 | if (max_tr.buffer) | |
3573 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
3574 | ||
3575 | mutex_unlock(&trace_types_lock); | |
3576 | ||
3577 | *fpos += cnt; | |
3578 | ||
3579 | return cnt; | |
3580 | } | |
3581 | ||
13f16d20 LZ |
3582 | static int tracing_clock_open(struct inode *inode, struct file *file) |
3583 | { | |
3584 | if (tracing_disabled) | |
3585 | return -ENODEV; | |
3586 | return single_open(file, tracing_clock_show, NULL); | |
3587 | } | |
3588 | ||
5e2336a0 | 3589 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3590 | .open = tracing_open_generic, |
3591 | .read = tracing_max_lat_read, | |
3592 | .write = tracing_max_lat_write, | |
b444786f | 3593 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3594 | }; |
3595 | ||
5e2336a0 | 3596 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3597 | .open = tracing_open_generic, |
3598 | .read = tracing_ctrl_read, | |
3599 | .write = tracing_ctrl_write, | |
b444786f | 3600 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3601 | }; |
3602 | ||
5e2336a0 | 3603 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3604 | .open = tracing_open_generic, |
3605 | .read = tracing_set_trace_read, | |
3606 | .write = tracing_set_trace_write, | |
b444786f | 3607 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3608 | }; |
3609 | ||
5e2336a0 | 3610 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3611 | .open = tracing_open_pipe, |
2a2cc8f7 | 3612 | .poll = tracing_poll_pipe, |
4bf39a94 | 3613 | .read = tracing_read_pipe, |
3c56819b | 3614 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3615 | .release = tracing_release_pipe, |
b444786f | 3616 | .llseek = no_llseek, |
b3806b43 SR |
3617 | }; |
3618 | ||
5e2336a0 | 3619 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3620 | .open = tracing_open_generic, |
3621 | .read = tracing_entries_read, | |
3622 | .write = tracing_entries_write, | |
b444786f | 3623 | .llseek = generic_file_llseek, |
a98a3c3f SR |
3624 | }; |
3625 | ||
5e2336a0 | 3626 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3627 | .open = tracing_open_generic, |
5bf9a1ee | 3628 | .write = tracing_mark_write, |
b444786f | 3629 | .llseek = generic_file_llseek, |
5bf9a1ee PP |
3630 | }; |
3631 | ||
5079f326 | 3632 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
3633 | .open = tracing_clock_open, |
3634 | .read = seq_read, | |
3635 | .llseek = seq_lseek, | |
3636 | .release = single_release, | |
5079f326 Z |
3637 | .write = tracing_clock_write, |
3638 | }; | |
3639 | ||
2cadf913 SR |
3640 | struct ftrace_buffer_info { |
3641 | struct trace_array *tr; | |
3642 | void *spare; | |
3643 | int cpu; | |
3644 | unsigned int read; | |
3645 | }; | |
3646 | ||
3647 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3648 | { | |
3649 | int cpu = (int)(long)inode->i_private; | |
3650 | struct ftrace_buffer_info *info; | |
3651 | ||
3652 | if (tracing_disabled) | |
3653 | return -ENODEV; | |
3654 | ||
3655 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3656 | if (!info) | |
3657 | return -ENOMEM; | |
3658 | ||
3659 | info->tr = &global_trace; | |
3660 | info->cpu = cpu; | |
ddd538f3 | 3661 | info->spare = NULL; |
2cadf913 SR |
3662 | /* Force reading ring buffer for first read */ |
3663 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3664 | |
3665 | filp->private_data = info; | |
3666 | ||
d1e7e02f | 3667 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3668 | } |
3669 | ||
3670 | static ssize_t | |
3671 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3672 | size_t count, loff_t *ppos) | |
3673 | { | |
3674 | struct ftrace_buffer_info *info = filp->private_data; | |
2cadf913 SR |
3675 | ssize_t ret; |
3676 | size_t size; | |
3677 | ||
2dc5d12b SR |
3678 | if (!count) |
3679 | return 0; | |
3680 | ||
ddd538f3 LJ |
3681 | if (!info->spare) |
3682 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3683 | if (!info->spare) | |
3684 | return -ENOMEM; | |
3685 | ||
2cadf913 SR |
3686 | /* Do we have previous read data to read? */ |
3687 | if (info->read < PAGE_SIZE) | |
3688 | goto read; | |
3689 | ||
3690 | info->read = 0; | |
3691 | ||
7e53bd42 | 3692 | trace_access_lock(info->cpu); |
2cadf913 SR |
3693 | ret = ring_buffer_read_page(info->tr->buffer, |
3694 | &info->spare, | |
3695 | count, | |
3696 | info->cpu, 0); | |
7e53bd42 | 3697 | trace_access_unlock(info->cpu); |
2cadf913 SR |
3698 | if (ret < 0) |
3699 | return 0; | |
3700 | ||
2cadf913 SR |
3701 | read: |
3702 | size = PAGE_SIZE - info->read; | |
3703 | if (size > count) | |
3704 | size = count; | |
3705 | ||
3706 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3707 | if (ret == size) |
2cadf913 | 3708 | return -EFAULT; |
2dc5d12b SR |
3709 | size -= ret; |
3710 | ||
2cadf913 SR |
3711 | *ppos += size; |
3712 | info->read += size; | |
3713 | ||
3714 | return size; | |
3715 | } | |
3716 | ||
3717 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3718 | { | |
3719 | struct ftrace_buffer_info *info = file->private_data; | |
3720 | ||
ddd538f3 LJ |
3721 | if (info->spare) |
3722 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3723 | kfree(info); |
3724 | ||
3725 | return 0; | |
3726 | } | |
3727 | ||
3728 | struct buffer_ref { | |
3729 | struct ring_buffer *buffer; | |
3730 | void *page; | |
3731 | int ref; | |
3732 | }; | |
3733 | ||
3734 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3735 | struct pipe_buffer *buf) | |
3736 | { | |
3737 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3738 | ||
3739 | if (--ref->ref) | |
3740 | return; | |
3741 | ||
3742 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3743 | kfree(ref); | |
3744 | buf->private = 0; | |
3745 | } | |
3746 | ||
3747 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3748 | struct pipe_buffer *buf) | |
3749 | { | |
3750 | return 1; | |
3751 | } | |
3752 | ||
3753 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3754 | struct pipe_buffer *buf) | |
3755 | { | |
3756 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3757 | ||
3758 | ref->ref++; | |
3759 | } | |
3760 | ||
3761 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 3762 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
3763 | .can_merge = 0, |
3764 | .map = generic_pipe_buf_map, | |
3765 | .unmap = generic_pipe_buf_unmap, | |
3766 | .confirm = generic_pipe_buf_confirm, | |
3767 | .release = buffer_pipe_buf_release, | |
3768 | .steal = buffer_pipe_buf_steal, | |
3769 | .get = buffer_pipe_buf_get, | |
3770 | }; | |
3771 | ||
3772 | /* | |
3773 | * Callback from splice_to_pipe(), if we need to release some pages | |
3774 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3775 | */ | |
3776 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3777 | { | |
3778 | struct buffer_ref *ref = | |
3779 | (struct buffer_ref *)spd->partial[i].private; | |
3780 | ||
3781 | if (--ref->ref) | |
3782 | return; | |
3783 | ||
3784 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3785 | kfree(ref); | |
3786 | spd->partial[i].private = 0; | |
3787 | } | |
3788 | ||
3789 | static ssize_t | |
3790 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3791 | struct pipe_inode_info *pipe, size_t len, | |
3792 | unsigned int flags) | |
3793 | { | |
3794 | struct ftrace_buffer_info *info = file->private_data; | |
35f3d14d JA |
3795 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
3796 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 3797 | struct splice_pipe_desc spd = { |
35f3d14d JA |
3798 | .pages = pages_def, |
3799 | .partial = partial_def, | |
2cadf913 SR |
3800 | .flags = flags, |
3801 | .ops = &buffer_pipe_buf_ops, | |
3802 | .spd_release = buffer_spd_release, | |
3803 | }; | |
3804 | struct buffer_ref *ref; | |
93459c6c | 3805 | int entries, size, i; |
2cadf913 SR |
3806 | size_t ret; |
3807 | ||
35f3d14d JA |
3808 | if (splice_grow_spd(pipe, &spd)) |
3809 | return -ENOMEM; | |
3810 | ||
93cfb3c9 LJ |
3811 | if (*ppos & (PAGE_SIZE - 1)) { |
3812 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
35f3d14d JA |
3813 | ret = -EINVAL; |
3814 | goto out; | |
93cfb3c9 LJ |
3815 | } |
3816 | ||
3817 | if (len & (PAGE_SIZE - 1)) { | |
3818 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
35f3d14d JA |
3819 | if (len < PAGE_SIZE) { |
3820 | ret = -EINVAL; | |
3821 | goto out; | |
3822 | } | |
93cfb3c9 LJ |
3823 | len &= PAGE_MASK; |
3824 | } | |
3825 | ||
7e53bd42 | 3826 | trace_access_lock(info->cpu); |
93459c6c SR |
3827 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
3828 | ||
35f3d14d | 3829 | for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
3830 | struct page *page; |
3831 | int r; | |
3832 | ||
3833 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3834 | if (!ref) | |
3835 | break; | |
3836 | ||
7267fa68 | 3837 | ref->ref = 1; |
2cadf913 SR |
3838 | ref->buffer = info->tr->buffer; |
3839 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3840 | if (!ref->page) { | |
3841 | kfree(ref); | |
3842 | break; | |
3843 | } | |
3844 | ||
3845 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 3846 | len, info->cpu, 1); |
2cadf913 SR |
3847 | if (r < 0) { |
3848 | ring_buffer_free_read_page(ref->buffer, | |
3849 | ref->page); | |
3850 | kfree(ref); | |
3851 | break; | |
3852 | } | |
3853 | ||
3854 | /* | |
3855 | * zero out any left over data, this is going to | |
3856 | * user land. | |
3857 | */ | |
3858 | size = ring_buffer_page_len(ref->page); | |
3859 | if (size < PAGE_SIZE) | |
3860 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3861 | ||
3862 | page = virt_to_page(ref->page); | |
3863 | ||
3864 | spd.pages[i] = page; | |
3865 | spd.partial[i].len = PAGE_SIZE; | |
3866 | spd.partial[i].offset = 0; | |
3867 | spd.partial[i].private = (unsigned long)ref; | |
3868 | spd.nr_pages++; | |
93cfb3c9 | 3869 | *ppos += PAGE_SIZE; |
93459c6c SR |
3870 | |
3871 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
3872 | } |
3873 | ||
7e53bd42 | 3874 | trace_access_unlock(info->cpu); |
2cadf913 SR |
3875 | spd.nr_pages = i; |
3876 | ||
3877 | /* did we read anything? */ | |
3878 | if (!spd.nr_pages) { | |
3879 | if (flags & SPLICE_F_NONBLOCK) | |
3880 | ret = -EAGAIN; | |
3881 | else | |
3882 | ret = 0; | |
3883 | /* TODO: block */ | |
35f3d14d | 3884 | goto out; |
2cadf913 SR |
3885 | } |
3886 | ||
3887 | ret = splice_to_pipe(pipe, &spd); | |
35f3d14d JA |
3888 | splice_shrink_spd(pipe, &spd); |
3889 | out: | |
2cadf913 SR |
3890 | return ret; |
3891 | } | |
3892 | ||
3893 | static const struct file_operations tracing_buffers_fops = { | |
3894 | .open = tracing_buffers_open, | |
3895 | .read = tracing_buffers_read, | |
3896 | .release = tracing_buffers_release, | |
3897 | .splice_read = tracing_buffers_splice_read, | |
3898 | .llseek = no_llseek, | |
3899 | }; | |
3900 | ||
c8d77183 SR |
3901 | static ssize_t |
3902 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
3903 | size_t count, loff_t *ppos) | |
3904 | { | |
3905 | unsigned long cpu = (unsigned long)filp->private_data; | |
3906 | struct trace_array *tr = &global_trace; | |
3907 | struct trace_seq *s; | |
3908 | unsigned long cnt; | |
3909 | ||
e4f2d10f | 3910 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 3911 | if (!s) |
a646365c | 3912 | return -ENOMEM; |
c8d77183 SR |
3913 | |
3914 | trace_seq_init(s); | |
3915 | ||
3916 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
3917 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
3918 | ||
3919 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
3920 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
3921 | ||
3922 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
3923 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
3924 | ||
c8d77183 SR |
3925 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
3926 | ||
3927 | kfree(s); | |
3928 | ||
3929 | return count; | |
3930 | } | |
3931 | ||
3932 | static const struct file_operations tracing_stats_fops = { | |
3933 | .open = tracing_open_generic, | |
3934 | .read = tracing_stats_read, | |
b444786f | 3935 | .llseek = generic_file_llseek, |
c8d77183 SR |
3936 | }; |
3937 | ||
bc0c38d1 SR |
3938 | #ifdef CONFIG_DYNAMIC_FTRACE |
3939 | ||
b807c3d0 SR |
3940 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3941 | { | |
3942 | return 0; | |
3943 | } | |
3944 | ||
bc0c38d1 | 3945 | static ssize_t |
b807c3d0 | 3946 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3947 | size_t cnt, loff_t *ppos) |
3948 | { | |
a26a2a27 SR |
3949 | static char ftrace_dyn_info_buffer[1024]; |
3950 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3951 | unsigned long *p = filp->private_data; |
b807c3d0 | 3952 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3953 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3954 | int r; |
3955 | ||
b807c3d0 SR |
3956 | mutex_lock(&dyn_info_mutex); |
3957 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3958 | |
a26a2a27 | 3959 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3960 | buf[r++] = '\n'; |
3961 | ||
3962 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3963 | ||
3964 | mutex_unlock(&dyn_info_mutex); | |
3965 | ||
3966 | return r; | |
bc0c38d1 SR |
3967 | } |
3968 | ||
5e2336a0 | 3969 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3970 | .open = tracing_open_generic, |
b807c3d0 | 3971 | .read = tracing_read_dyn_info, |
b444786f | 3972 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3973 | }; |
3974 | #endif | |
3975 | ||
3976 | static struct dentry *d_tracer; | |
3977 | ||
3978 | struct dentry *tracing_init_dentry(void) | |
3979 | { | |
3980 | static int once; | |
3981 | ||
3982 | if (d_tracer) | |
3983 | return d_tracer; | |
3984 | ||
3e1f60b8 FW |
3985 | if (!debugfs_initialized()) |
3986 | return NULL; | |
3987 | ||
bc0c38d1 SR |
3988 | d_tracer = debugfs_create_dir("tracing", NULL); |
3989 | ||
3990 | if (!d_tracer && !once) { | |
3991 | once = 1; | |
3992 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3993 | return NULL; | |
3994 | } | |
3995 | ||
3996 | return d_tracer; | |
3997 | } | |
3998 | ||
b04cc6b1 FW |
3999 | static struct dentry *d_percpu; |
4000 | ||
4001 | struct dentry *tracing_dentry_percpu(void) | |
4002 | { | |
4003 | static int once; | |
4004 | struct dentry *d_tracer; | |
4005 | ||
4006 | if (d_percpu) | |
4007 | return d_percpu; | |
4008 | ||
4009 | d_tracer = tracing_init_dentry(); | |
4010 | ||
4011 | if (!d_tracer) | |
4012 | return NULL; | |
4013 | ||
4014 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
4015 | ||
4016 | if (!d_percpu && !once) { | |
4017 | once = 1; | |
4018 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
4019 | return NULL; | |
4020 | } | |
4021 | ||
4022 | return d_percpu; | |
4023 | } | |
4024 | ||
4025 | static void tracing_init_debugfs_percpu(long cpu) | |
4026 | { | |
4027 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 4028 | struct dentry *d_cpu; |
dd49a38c | 4029 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 4030 | |
dd49a38c | 4031 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
4032 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
4033 | if (!d_cpu) { | |
4034 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
4035 | return; | |
4036 | } | |
b04cc6b1 | 4037 | |
8656e7a2 | 4038 | /* per cpu trace_pipe */ |
5452af66 FW |
4039 | trace_create_file("trace_pipe", 0444, d_cpu, |
4040 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
4041 | |
4042 | /* per cpu trace */ | |
5452af66 FW |
4043 | trace_create_file("trace", 0644, d_cpu, |
4044 | (void *) cpu, &tracing_fops); | |
7f96f93f | 4045 | |
5452af66 FW |
4046 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
4047 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 4048 | |
c8d77183 SR |
4049 | trace_create_file("stats", 0444, d_cpu, |
4050 | (void *) cpu, &tracing_stats_fops); | |
b04cc6b1 FW |
4051 | } |
4052 | ||
60a11774 SR |
4053 | #ifdef CONFIG_FTRACE_SELFTEST |
4054 | /* Let selftest have access to static functions in this file */ | |
4055 | #include "trace_selftest.c" | |
4056 | #endif | |
4057 | ||
577b785f SR |
4058 | struct trace_option_dentry { |
4059 | struct tracer_opt *opt; | |
4060 | struct tracer_flags *flags; | |
4061 | struct dentry *entry; | |
4062 | }; | |
4063 | ||
4064 | static ssize_t | |
4065 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4066 | loff_t *ppos) | |
4067 | { | |
4068 | struct trace_option_dentry *topt = filp->private_data; | |
4069 | char *buf; | |
4070 | ||
4071 | if (topt->flags->val & topt->opt->bit) | |
4072 | buf = "1\n"; | |
4073 | else | |
4074 | buf = "0\n"; | |
4075 | ||
4076 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4077 | } | |
4078 | ||
4079 | static ssize_t | |
4080 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4081 | loff_t *ppos) | |
4082 | { | |
4083 | struct trace_option_dentry *topt = filp->private_data; | |
4084 | unsigned long val; | |
4085 | char buf[64]; | |
4086 | int ret; | |
4087 | ||
4088 | if (cnt >= sizeof(buf)) | |
4089 | return -EINVAL; | |
4090 | ||
4091 | if (copy_from_user(&buf, ubuf, cnt)) | |
4092 | return -EFAULT; | |
4093 | ||
4094 | buf[cnt] = 0; | |
4095 | ||
4096 | ret = strict_strtoul(buf, 10, &val); | |
4097 | if (ret < 0) | |
4098 | return ret; | |
4099 | ||
8d18eaaf LZ |
4100 | if (val != 0 && val != 1) |
4101 | return -EINVAL; | |
577b785f | 4102 | |
8d18eaaf | 4103 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 4104 | mutex_lock(&trace_types_lock); |
8d18eaaf | 4105 | ret = __set_tracer_option(current_trace, topt->flags, |
c757bea9 | 4106 | topt->opt, !val); |
577b785f SR |
4107 | mutex_unlock(&trace_types_lock); |
4108 | if (ret) | |
4109 | return ret; | |
577b785f SR |
4110 | } |
4111 | ||
4112 | *ppos += cnt; | |
4113 | ||
4114 | return cnt; | |
4115 | } | |
4116 | ||
4117 | ||
4118 | static const struct file_operations trace_options_fops = { | |
4119 | .open = tracing_open_generic, | |
4120 | .read = trace_options_read, | |
4121 | .write = trace_options_write, | |
b444786f | 4122 | .llseek = generic_file_llseek, |
577b785f SR |
4123 | }; |
4124 | ||
a8259075 SR |
4125 | static ssize_t |
4126 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4127 | loff_t *ppos) | |
4128 | { | |
4129 | long index = (long)filp->private_data; | |
4130 | char *buf; | |
4131 | ||
4132 | if (trace_flags & (1 << index)) | |
4133 | buf = "1\n"; | |
4134 | else | |
4135 | buf = "0\n"; | |
4136 | ||
4137 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4138 | } | |
4139 | ||
4140 | static ssize_t | |
4141 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4142 | loff_t *ppos) | |
4143 | { | |
4144 | long index = (long)filp->private_data; | |
4145 | char buf[64]; | |
4146 | unsigned long val; | |
4147 | int ret; | |
4148 | ||
4149 | if (cnt >= sizeof(buf)) | |
4150 | return -EINVAL; | |
4151 | ||
4152 | if (copy_from_user(&buf, ubuf, cnt)) | |
4153 | return -EFAULT; | |
4154 | ||
4155 | buf[cnt] = 0; | |
4156 | ||
4157 | ret = strict_strtoul(buf, 10, &val); | |
4158 | if (ret < 0) | |
4159 | return ret; | |
4160 | ||
f2d84b65 | 4161 | if (val != 0 && val != 1) |
a8259075 | 4162 | return -EINVAL; |
f2d84b65 | 4163 | set_tracer_flags(1 << index, val); |
a8259075 SR |
4164 | |
4165 | *ppos += cnt; | |
4166 | ||
4167 | return cnt; | |
4168 | } | |
4169 | ||
a8259075 SR |
4170 | static const struct file_operations trace_options_core_fops = { |
4171 | .open = tracing_open_generic, | |
4172 | .read = trace_options_core_read, | |
4173 | .write = trace_options_core_write, | |
b444786f | 4174 | .llseek = generic_file_llseek, |
a8259075 SR |
4175 | }; |
4176 | ||
5452af66 FW |
4177 | struct dentry *trace_create_file(const char *name, |
4178 | mode_t mode, | |
4179 | struct dentry *parent, | |
4180 | void *data, | |
4181 | const struct file_operations *fops) | |
4182 | { | |
4183 | struct dentry *ret; | |
4184 | ||
4185 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
4186 | if (!ret) | |
4187 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
4188 | ||
4189 | return ret; | |
4190 | } | |
4191 | ||
4192 | ||
a8259075 SR |
4193 | static struct dentry *trace_options_init_dentry(void) |
4194 | { | |
4195 | struct dentry *d_tracer; | |
4196 | static struct dentry *t_options; | |
4197 | ||
4198 | if (t_options) | |
4199 | return t_options; | |
4200 | ||
4201 | d_tracer = tracing_init_dentry(); | |
4202 | if (!d_tracer) | |
4203 | return NULL; | |
4204 | ||
4205 | t_options = debugfs_create_dir("options", d_tracer); | |
4206 | if (!t_options) { | |
4207 | pr_warning("Could not create debugfs directory 'options'\n"); | |
4208 | return NULL; | |
4209 | } | |
4210 | ||
4211 | return t_options; | |
4212 | } | |
4213 | ||
577b785f SR |
4214 | static void |
4215 | create_trace_option_file(struct trace_option_dentry *topt, | |
4216 | struct tracer_flags *flags, | |
4217 | struct tracer_opt *opt) | |
4218 | { | |
4219 | struct dentry *t_options; | |
577b785f SR |
4220 | |
4221 | t_options = trace_options_init_dentry(); | |
4222 | if (!t_options) | |
4223 | return; | |
4224 | ||
4225 | topt->flags = flags; | |
4226 | topt->opt = opt; | |
4227 | ||
5452af66 | 4228 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
4229 | &trace_options_fops); |
4230 | ||
577b785f SR |
4231 | } |
4232 | ||
4233 | static struct trace_option_dentry * | |
4234 | create_trace_option_files(struct tracer *tracer) | |
4235 | { | |
4236 | struct trace_option_dentry *topts; | |
4237 | struct tracer_flags *flags; | |
4238 | struct tracer_opt *opts; | |
4239 | int cnt; | |
4240 | ||
4241 | if (!tracer) | |
4242 | return NULL; | |
4243 | ||
4244 | flags = tracer->flags; | |
4245 | ||
4246 | if (!flags || !flags->opts) | |
4247 | return NULL; | |
4248 | ||
4249 | opts = flags->opts; | |
4250 | ||
4251 | for (cnt = 0; opts[cnt].name; cnt++) | |
4252 | ; | |
4253 | ||
0cfe8245 | 4254 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
4255 | if (!topts) |
4256 | return NULL; | |
4257 | ||
4258 | for (cnt = 0; opts[cnt].name; cnt++) | |
4259 | create_trace_option_file(&topts[cnt], flags, | |
4260 | &opts[cnt]); | |
4261 | ||
4262 | return topts; | |
4263 | } | |
4264 | ||
4265 | static void | |
4266 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
4267 | { | |
4268 | int cnt; | |
4269 | ||
4270 | if (!topts) | |
4271 | return; | |
4272 | ||
4273 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
4274 | if (topts[cnt].entry) | |
4275 | debugfs_remove(topts[cnt].entry); | |
4276 | } | |
4277 | ||
4278 | kfree(topts); | |
4279 | } | |
4280 | ||
a8259075 SR |
4281 | static struct dentry * |
4282 | create_trace_option_core_file(const char *option, long index) | |
4283 | { | |
4284 | struct dentry *t_options; | |
a8259075 SR |
4285 | |
4286 | t_options = trace_options_init_dentry(); | |
4287 | if (!t_options) | |
4288 | return NULL; | |
4289 | ||
5452af66 | 4290 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 4291 | &trace_options_core_fops); |
a8259075 SR |
4292 | } |
4293 | ||
4294 | static __init void create_trace_options_dir(void) | |
4295 | { | |
4296 | struct dentry *t_options; | |
a8259075 SR |
4297 | int i; |
4298 | ||
4299 | t_options = trace_options_init_dentry(); | |
4300 | if (!t_options) | |
4301 | return; | |
4302 | ||
5452af66 FW |
4303 | for (i = 0; trace_options[i]; i++) |
4304 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4305 | } |
4306 | ||
b5ad384e | 4307 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4308 | { |
4309 | struct dentry *d_tracer; | |
b04cc6b1 | 4310 | int cpu; |
bc0c38d1 | 4311 | |
7e53bd42 LJ |
4312 | trace_access_lock_init(); |
4313 | ||
bc0c38d1 SR |
4314 | d_tracer = tracing_init_dentry(); |
4315 | ||
5452af66 FW |
4316 | trace_create_file("tracing_enabled", 0644, d_tracer, |
4317 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 4318 | |
5452af66 FW |
4319 | trace_create_file("trace_options", 0644, d_tracer, |
4320 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4321 | |
5452af66 FW |
4322 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4323 | NULL, &tracing_cpumask_fops); | |
4324 | ||
4325 | trace_create_file("trace", 0644, d_tracer, | |
4326 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 4327 | |
5452af66 FW |
4328 | trace_create_file("available_tracers", 0444, d_tracer, |
4329 | &global_trace, &show_traces_fops); | |
4330 | ||
339ae5d3 | 4331 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4332 | &global_trace, &set_tracer_fops); |
4333 | ||
5d4a9dba | 4334 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
4335 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
4336 | &tracing_max_latency, &tracing_max_lat_fops); | |
0e950173 | 4337 | #endif |
5452af66 FW |
4338 | |
4339 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4340 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 4341 | |
339ae5d3 | 4342 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4343 | NULL, &tracing_readme_fops); |
4344 | ||
4345 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4346 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4347 | |
4348 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
4349 | &global_trace, &tracing_entries_fops); | |
4350 | ||
4351 | trace_create_file("trace_marker", 0220, d_tracer, | |
4352 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4353 | |
69abe6a5 AP |
4354 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4355 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 4356 | |
5079f326 Z |
4357 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
4358 | &trace_clock_fops); | |
4359 | ||
bc0c38d1 | 4360 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4361 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4362 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4363 | #endif |
b04cc6b1 | 4364 | |
5452af66 FW |
4365 | create_trace_options_dir(); |
4366 | ||
b04cc6b1 FW |
4367 | for_each_tracing_cpu(cpu) |
4368 | tracing_init_debugfs_percpu(cpu); | |
4369 | ||
b5ad384e | 4370 | return 0; |
bc0c38d1 SR |
4371 | } |
4372 | ||
3f5a54e3 SR |
4373 | static int trace_panic_handler(struct notifier_block *this, |
4374 | unsigned long event, void *unused) | |
4375 | { | |
944ac425 | 4376 | if (ftrace_dump_on_oops) |
cecbca96 | 4377 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4378 | return NOTIFY_OK; |
4379 | } | |
4380 | ||
4381 | static struct notifier_block trace_panic_notifier = { | |
4382 | .notifier_call = trace_panic_handler, | |
4383 | .next = NULL, | |
4384 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4385 | }; | |
4386 | ||
4387 | static int trace_die_handler(struct notifier_block *self, | |
4388 | unsigned long val, | |
4389 | void *data) | |
4390 | { | |
4391 | switch (val) { | |
4392 | case DIE_OOPS: | |
944ac425 | 4393 | if (ftrace_dump_on_oops) |
cecbca96 | 4394 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4395 | break; |
4396 | default: | |
4397 | break; | |
4398 | } | |
4399 | return NOTIFY_OK; | |
4400 | } | |
4401 | ||
4402 | static struct notifier_block trace_die_notifier = { | |
4403 | .notifier_call = trace_die_handler, | |
4404 | .priority = 200 | |
4405 | }; | |
4406 | ||
4407 | /* | |
4408 | * printk is set to max of 1024, we really don't need it that big. | |
4409 | * Nothing should be printing 1000 characters anyway. | |
4410 | */ | |
4411 | #define TRACE_MAX_PRINT 1000 | |
4412 | ||
4413 | /* | |
4414 | * Define here KERN_TRACE so that we have one place to modify | |
4415 | * it if we decide to change what log level the ftrace dump | |
4416 | * should be at. | |
4417 | */ | |
428aee14 | 4418 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 4419 | |
955b61e5 | 4420 | void |
3f5a54e3 SR |
4421 | trace_printk_seq(struct trace_seq *s) |
4422 | { | |
4423 | /* Probably should print a warning here. */ | |
4424 | if (s->len >= 1000) | |
4425 | s->len = 1000; | |
4426 | ||
4427 | /* should be zero ended, but we are paranoid. */ | |
4428 | s->buffer[s->len] = 0; | |
4429 | ||
4430 | printk(KERN_TRACE "%s", s->buffer); | |
4431 | ||
f9520750 | 4432 | trace_seq_init(s); |
3f5a54e3 SR |
4433 | } |
4434 | ||
955b61e5 JW |
4435 | void trace_init_global_iter(struct trace_iterator *iter) |
4436 | { | |
4437 | iter->tr = &global_trace; | |
4438 | iter->trace = current_trace; | |
4439 | iter->cpu_file = TRACE_PIPE_ALL_CPU; | |
4440 | } | |
4441 | ||
cecbca96 FW |
4442 | static void |
4443 | __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode) | |
3f5a54e3 | 4444 | { |
445c8951 | 4445 | static arch_spinlock_t ftrace_dump_lock = |
edc35bd7 | 4446 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
3f5a54e3 SR |
4447 | /* use static because iter can be a bit big for the stack */ |
4448 | static struct trace_iterator iter; | |
cf586b61 | 4449 | unsigned int old_userobj; |
3f5a54e3 | 4450 | static int dump_ran; |
d769041f SR |
4451 | unsigned long flags; |
4452 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4453 | |
4454 | /* only one dump */ | |
cd891ae0 | 4455 | local_irq_save(flags); |
0199c4e6 | 4456 | arch_spin_lock(&ftrace_dump_lock); |
3f5a54e3 SR |
4457 | if (dump_ran) |
4458 | goto out; | |
4459 | ||
4460 | dump_ran = 1; | |
4461 | ||
0ee6b6cf | 4462 | tracing_off(); |
cf586b61 FW |
4463 | |
4464 | if (disable_tracing) | |
4465 | ftrace_kill(); | |
3f5a54e3 | 4466 | |
955b61e5 JW |
4467 | trace_init_global_iter(&iter); |
4468 | ||
d769041f | 4469 | for_each_tracing_cpu(cpu) { |
955b61e5 | 4470 | atomic_inc(&iter.tr->data[cpu]->disabled); |
d769041f SR |
4471 | } |
4472 | ||
cf586b61 FW |
4473 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4474 | ||
b54d3de9 TE |
4475 | /* don't look at user memory in panic mode */ |
4476 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4477 | ||
e543ad76 | 4478 | /* Simulate the iterator */ |
3f5a54e3 SR |
4479 | iter.tr = &global_trace; |
4480 | iter.trace = current_trace; | |
cecbca96 FW |
4481 | |
4482 | switch (oops_dump_mode) { | |
4483 | case DUMP_ALL: | |
4484 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
4485 | break; | |
4486 | case DUMP_ORIG: | |
4487 | iter.cpu_file = raw_smp_processor_id(); | |
4488 | break; | |
4489 | case DUMP_NONE: | |
4490 | goto out_enable; | |
4491 | default: | |
4492 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
4493 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
4494 | } | |
4495 | ||
4496 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 SR |
4497 | |
4498 | /* | |
4499 | * We need to stop all tracing on all CPUS to read the | |
4500 | * the next buffer. This is a bit expensive, but is | |
4501 | * not done often. We fill all what we can read, | |
4502 | * and then release the locks again. | |
4503 | */ | |
4504 | ||
3f5a54e3 SR |
4505 | while (!trace_empty(&iter)) { |
4506 | ||
4507 | if (!cnt) | |
4508 | printk(KERN_TRACE "---------------------------------\n"); | |
4509 | ||
4510 | cnt++; | |
4511 | ||
4512 | /* reset all but tr, trace, and overruns */ | |
4513 | memset(&iter.seq, 0, | |
4514 | sizeof(struct trace_iterator) - | |
4515 | offsetof(struct trace_iterator, seq)); | |
4516 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4517 | iter.pos = -1; | |
4518 | ||
955b61e5 | 4519 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
4520 | int ret; |
4521 | ||
4522 | ret = print_trace_line(&iter); | |
4523 | if (ret != TRACE_TYPE_NO_CONSUME) | |
4524 | trace_consume(&iter); | |
3f5a54e3 SR |
4525 | } |
4526 | ||
4527 | trace_printk_seq(&iter.seq); | |
4528 | } | |
4529 | ||
4530 | if (!cnt) | |
4531 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4532 | else | |
4533 | printk(KERN_TRACE "---------------------------------\n"); | |
4534 | ||
cecbca96 | 4535 | out_enable: |
cf586b61 FW |
4536 | /* Re-enable tracing if requested */ |
4537 | if (!disable_tracing) { | |
4538 | trace_flags |= old_userobj; | |
4539 | ||
4540 | for_each_tracing_cpu(cpu) { | |
955b61e5 | 4541 | atomic_dec(&iter.tr->data[cpu]->disabled); |
cf586b61 FW |
4542 | } |
4543 | tracing_on(); | |
4544 | } | |
4545 | ||
3f5a54e3 | 4546 | out: |
0199c4e6 | 4547 | arch_spin_unlock(&ftrace_dump_lock); |
cd891ae0 | 4548 | local_irq_restore(flags); |
3f5a54e3 SR |
4549 | } |
4550 | ||
cf586b61 | 4551 | /* By default: disable tracing after the dump */ |
cecbca96 | 4552 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
cf586b61 | 4553 | { |
cecbca96 | 4554 | __ftrace_dump(true, oops_dump_mode); |
cf586b61 FW |
4555 | } |
4556 | ||
3928a8a2 | 4557 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4558 | { |
73c5162a | 4559 | int ring_buf_size; |
750912fa | 4560 | enum ring_buffer_flags rb_flags; |
4c11d7ae | 4561 | int i; |
9e01c1b7 | 4562 | int ret = -ENOMEM; |
4c11d7ae | 4563 | |
750912fa | 4564 | |
9e01c1b7 RR |
4565 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4566 | goto out; | |
4567 | ||
4568 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4569 | goto out_free_buffer_mask; | |
4c11d7ae | 4570 | |
73c5162a SR |
4571 | /* To save memory, keep the ring buffer size to its minimum */ |
4572 | if (ring_buffer_expanded) | |
4573 | ring_buf_size = trace_buf_size; | |
4574 | else | |
4575 | ring_buf_size = 1; | |
4576 | ||
750912fa DS |
4577 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; |
4578 | ||
9e01c1b7 RR |
4579 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4580 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
4581 | ||
4582 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
750912fa | 4583 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, rb_flags); |
3928a8a2 SR |
4584 | if (!global_trace.buffer) { |
4585 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4586 | WARN_ON(1); | |
9e01c1b7 | 4587 | goto out_free_cpumask; |
4c11d7ae | 4588 | } |
3928a8a2 | 4589 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4590 | |
9e01c1b7 | 4591 | |
4c11d7ae | 4592 | #ifdef CONFIG_TRACER_MAX_TRACE |
750912fa | 4593 | max_tr.buffer = ring_buffer_alloc(1, rb_flags); |
3928a8a2 SR |
4594 | if (!max_tr.buffer) { |
4595 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4596 | WARN_ON(1); | |
4597 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4598 | goto out_free_cpumask; |
4c11d7ae | 4599 | } |
ef710e10 | 4600 | max_tr.entries = 1; |
a98a3c3f | 4601 | #endif |
ab46428c | 4602 | |
4c11d7ae | 4603 | /* Allocate the first page for all buffers */ |
ab46428c | 4604 | for_each_tracing_cpu(i) { |
566b0aaf | 4605 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
9705f69e | 4606 | max_tr.data[i] = &per_cpu(max_tr_data, i); |
4c11d7ae | 4607 | } |
bc0c38d1 | 4608 | |
bc0c38d1 SR |
4609 | trace_init_cmdlines(); |
4610 | ||
43a15386 | 4611 | register_tracer(&nop_trace); |
79fb0768 | 4612 | current_trace = &nop_trace; |
60a11774 SR |
4613 | /* All seems OK, enable tracing */ |
4614 | tracing_disabled = 0; | |
3928a8a2 | 4615 | |
3f5a54e3 SR |
4616 | atomic_notifier_chain_register(&panic_notifier_list, |
4617 | &trace_panic_notifier); | |
4618 | ||
4619 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4620 | |
4621 | return 0; | |
3f5a54e3 | 4622 | |
9e01c1b7 RR |
4623 | out_free_cpumask: |
4624 | free_cpumask_var(tracing_cpumask); | |
4625 | out_free_buffer_mask: | |
4626 | free_cpumask_var(tracing_buffer_mask); | |
4627 | out: | |
4628 | return ret; | |
bc0c38d1 | 4629 | } |
b2821ae6 SR |
4630 | |
4631 | __init static int clear_boot_tracer(void) | |
4632 | { | |
4633 | /* | |
4634 | * The default tracer at boot buffer is an init section. | |
4635 | * This function is called in lateinit. If we did not | |
4636 | * find the boot tracer, then clear it out, to prevent | |
4637 | * later registration from accessing the buffer that is | |
4638 | * about to be freed. | |
4639 | */ | |
4640 | if (!default_bootup_tracer) | |
4641 | return 0; | |
4642 | ||
4643 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4644 | default_bootup_tracer); | |
4645 | default_bootup_tracer = NULL; | |
4646 | ||
4647 | return 0; | |
4648 | } | |
4649 | ||
b5ad384e FW |
4650 | early_initcall(tracer_alloc_buffers); |
4651 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4652 | late_initcall(clear_boot_tracer); |