Commit | Line | Data |
---|---|---|
bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
2b6080f2 | 4 | * Copyright (C) 2007-2012 Steven Rostedt <srostedt@redhat.com> |
bc0c38d1 SR |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
6d49e352 | 12 | * Copyright (C) 2004 Nadia Yvette Chambers |
bc0c38d1 | 13 | */ |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
273b281f | 15 | #include <generated/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
4c11d7ae | 23 | #include <linux/pagemap.h> |
bc0c38d1 SR |
24 | #include <linux/hardirq.h> |
25 | #include <linux/linkage.h> | |
26 | #include <linux/uaccess.h> | |
2cadf913 | 27 | #include <linux/kprobes.h> |
bc0c38d1 SR |
28 | #include <linux/ftrace.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/percpu.h> | |
2cadf913 | 31 | #include <linux/splice.h> |
3f5a54e3 | 32 | #include <linux/kdebug.h> |
5f0c6c03 | 33 | #include <linux/string.h> |
7e53bd42 | 34 | #include <linux/rwsem.h> |
5a0e3ad6 | 35 | #include <linux/slab.h> |
bc0c38d1 SR |
36 | #include <linux/ctype.h> |
37 | #include <linux/init.h> | |
2a2cc8f7 | 38 | #include <linux/poll.h> |
b892e5c8 | 39 | #include <linux/nmi.h> |
bc0c38d1 | 40 | #include <linux/fs.h> |
8bd75c77 | 41 | #include <linux/sched/rt.h> |
86387f7e | 42 | |
bc0c38d1 | 43 | #include "trace.h" |
f0868d1e | 44 | #include "trace_output.h" |
bc0c38d1 | 45 | |
73c5162a SR |
46 | /* |
47 | * On boot up, the ring buffer is set to the minimum size, so that | |
48 | * we do not waste memory on systems that are not using tracing. | |
49 | */ | |
55034cd6 | 50 | bool ring_buffer_expanded; |
73c5162a | 51 | |
8e1b82e0 FW |
52 | /* |
53 | * We need to change this state when a selftest is running. | |
ff32504f FW |
54 | * A selftest will lurk into the ring-buffer to count the |
55 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 56 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
57 | * at the same time, giving false positive or negative results. |
58 | */ | |
8e1b82e0 | 59 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 60 | |
b2821ae6 SR |
61 | /* |
62 | * If a tracer is running, we do not want to run SELFTEST. | |
63 | */ | |
020e5f85 | 64 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 65 | |
adf9f195 FW |
66 | /* For tracers that don't implement custom flags */ |
67 | static struct tracer_opt dummy_tracer_opt[] = { | |
68 | { } | |
69 | }; | |
70 | ||
71 | static struct tracer_flags dummy_tracer_flags = { | |
72 | .val = 0, | |
73 | .opts = dummy_tracer_opt | |
74 | }; | |
75 | ||
76 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
77 | { | |
78 | return 0; | |
79 | } | |
0f048701 | 80 | |
7ffbd48d SR |
81 | /* |
82 | * To prevent the comm cache from being overwritten when no | |
83 | * tracing is active, only save the comm when a trace event | |
84 | * occurred. | |
85 | */ | |
86 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
87 | ||
0f048701 SR |
88 | /* |
89 | * Kill all tracing for good (never come back). | |
90 | * It is initialized to 1 but will turn to zero if the initialization | |
91 | * of the tracer is successful. But that is the only place that sets | |
92 | * this back to zero. | |
93 | */ | |
4fd27358 | 94 | static int tracing_disabled = 1; |
0f048701 | 95 | |
9288f99a | 96 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 97 | |
955b61e5 | 98 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 99 | |
944ac425 SR |
100 | /* |
101 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
102 | * | |
103 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
104 | * is set, then ftrace_dump is called. This will output the contents | |
105 | * of the ftrace buffers to the console. This is very useful for | |
106 | * capturing traces that lead to crashes and outputing it to a | |
107 | * serial console. | |
108 | * | |
109 | * It is default off, but you can enable it with either specifying | |
110 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
111 | * /proc/sys/kernel/ftrace_dump_on_oops |
112 | * Set 1 if you want to dump buffers of all CPUs | |
113 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 114 | */ |
cecbca96 FW |
115 | |
116 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 117 | |
de7edd31 SRRH |
118 | /* When set, tracing will stop when a WARN*() is hit */ |
119 | int __disable_trace_on_warning; | |
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 | |
55034cd6 SRRH |
127 | static bool allocate_snapshot; |
128 | ||
1beee96b | 129 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 130 | { |
67012ab1 | 131 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 132 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 133 | /* We are using ftrace early, expand it */ |
55034cd6 | 134 | ring_buffer_expanded = true; |
d9e54076 PZ |
135 | return 1; |
136 | } | |
1beee96b | 137 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 138 | |
944ac425 SR |
139 | static int __init set_ftrace_dump_on_oops(char *str) |
140 | { | |
cecbca96 FW |
141 | if (*str++ != '=' || !*str) { |
142 | ftrace_dump_on_oops = DUMP_ALL; | |
143 | return 1; | |
144 | } | |
145 | ||
146 | if (!strcmp("orig_cpu", str)) { | |
147 | ftrace_dump_on_oops = DUMP_ORIG; | |
148 | return 1; | |
149 | } | |
150 | ||
151 | return 0; | |
944ac425 SR |
152 | } |
153 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 154 | |
de7edd31 SRRH |
155 | static int __init stop_trace_on_warning(char *str) |
156 | { | |
157 | __disable_trace_on_warning = 1; | |
158 | return 1; | |
159 | } | |
160 | __setup("traceoff_on_warning=", stop_trace_on_warning); | |
161 | ||
3209cff4 | 162 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
163 | { |
164 | allocate_snapshot = true; | |
165 | /* We also need the main ring buffer expanded */ | |
166 | ring_buffer_expanded = true; | |
167 | return 1; | |
168 | } | |
3209cff4 | 169 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 170 | |
7bcfaf54 SR |
171 | |
172 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
173 | static char *trace_boot_options __initdata; | |
174 | ||
175 | static int __init set_trace_boot_options(char *str) | |
176 | { | |
67012ab1 | 177 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
178 | trace_boot_options = trace_boot_options_buf; |
179 | return 0; | |
180 | } | |
181 | __setup("trace_options=", set_trace_boot_options); | |
182 | ||
de7edd31 | 183 | |
cf8e3474 | 184 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
185 | { |
186 | nsec += 500; | |
187 | do_div(nsec, 1000); | |
188 | return nsec; | |
189 | } | |
190 | ||
4fcdae83 SR |
191 | /* |
192 | * The global_trace is the descriptor that holds the tracing | |
193 | * buffers for the live tracing. For each CPU, it contains | |
194 | * a link list of pages that will store trace entries. The | |
195 | * page descriptor of the pages in the memory is used to hold | |
196 | * the link list by linking the lru item in the page descriptor | |
197 | * to each of the pages in the buffer per CPU. | |
198 | * | |
199 | * For each active CPU there is a data field that holds the | |
200 | * pages for the buffer for that CPU. Each CPU has the same number | |
201 | * of pages allocated for its buffer. | |
202 | */ | |
bc0c38d1 SR |
203 | static struct trace_array global_trace; |
204 | ||
ae63b31e | 205 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 206 | |
ff451961 SRRH |
207 | int trace_array_get(struct trace_array *this_tr) |
208 | { | |
209 | struct trace_array *tr; | |
210 | int ret = -ENODEV; | |
211 | ||
212 | mutex_lock(&trace_types_lock); | |
213 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
214 | if (tr == this_tr) { | |
215 | tr->ref++; | |
216 | ret = 0; | |
217 | break; | |
218 | } | |
219 | } | |
220 | mutex_unlock(&trace_types_lock); | |
221 | ||
222 | return ret; | |
223 | } | |
224 | ||
225 | static void __trace_array_put(struct trace_array *this_tr) | |
226 | { | |
227 | WARN_ON(!this_tr->ref); | |
228 | this_tr->ref--; | |
229 | } | |
230 | ||
231 | void trace_array_put(struct trace_array *this_tr) | |
232 | { | |
233 | mutex_lock(&trace_types_lock); | |
234 | __trace_array_put(this_tr); | |
235 | mutex_unlock(&trace_types_lock); | |
236 | } | |
237 | ||
f306cc82 TZ |
238 | int filter_check_discard(struct ftrace_event_file *file, void *rec, |
239 | struct ring_buffer *buffer, | |
240 | struct ring_buffer_event *event) | |
eb02ce01 | 241 | { |
f306cc82 TZ |
242 | if (unlikely(file->flags & FTRACE_EVENT_FL_FILTERED) && |
243 | !filter_match_preds(file->filter, rec)) { | |
244 | ring_buffer_discard_commit(buffer, event); | |
245 | return 1; | |
246 | } | |
247 | ||
248 | return 0; | |
249 | } | |
250 | EXPORT_SYMBOL_GPL(filter_check_discard); | |
251 | ||
252 | int call_filter_check_discard(struct ftrace_event_call *call, void *rec, | |
253 | struct ring_buffer *buffer, | |
254 | struct ring_buffer_event *event) | |
255 | { | |
256 | if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && | |
257 | !filter_match_preds(call->filter, rec)) { | |
258 | ring_buffer_discard_commit(buffer, event); | |
259 | return 1; | |
260 | } | |
261 | ||
262 | return 0; | |
eb02ce01 | 263 | } |
f306cc82 | 264 | EXPORT_SYMBOL_GPL(call_filter_check_discard); |
eb02ce01 | 265 | |
9457158b | 266 | cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) |
37886f6a SR |
267 | { |
268 | u64 ts; | |
269 | ||
270 | /* Early boot up does not have a buffer yet */ | |
9457158b | 271 | if (!buf->buffer) |
37886f6a SR |
272 | return trace_clock_local(); |
273 | ||
9457158b AL |
274 | ts = ring_buffer_time_stamp(buf->buffer, cpu); |
275 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); | |
37886f6a SR |
276 | |
277 | return ts; | |
278 | } | |
bc0c38d1 | 279 | |
9457158b AL |
280 | cycle_t ftrace_now(int cpu) |
281 | { | |
282 | return buffer_ftrace_now(&global_trace.trace_buffer, cpu); | |
283 | } | |
284 | ||
10246fa3 SRRH |
285 | /** |
286 | * tracing_is_enabled - Show if global_trace has been disabled | |
287 | * | |
288 | * Shows if the global trace has been enabled or not. It uses the | |
289 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
290 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
291 | * need to know the accurate state, use tracing_is_on() which is a little | |
292 | * slower, but accurate. | |
293 | */ | |
9036990d SR |
294 | int tracing_is_enabled(void) |
295 | { | |
10246fa3 SRRH |
296 | /* |
297 | * For quick access (irqsoff uses this in fast path), just | |
298 | * return the mirror variable of the state of the ring buffer. | |
299 | * It's a little racy, but we don't really care. | |
300 | */ | |
301 | smp_rmb(); | |
302 | return !global_trace.buffer_disabled; | |
9036990d SR |
303 | } |
304 | ||
4fcdae83 | 305 | /* |
3928a8a2 SR |
306 | * trace_buf_size is the size in bytes that is allocated |
307 | * for a buffer. Note, the number of bytes is always rounded | |
308 | * to page size. | |
3f5a54e3 SR |
309 | * |
310 | * This number is purposely set to a low number of 16384. | |
311 | * If the dump on oops happens, it will be much appreciated | |
312 | * to not have to wait for all that output. Anyway this can be | |
313 | * boot time and run time configurable. | |
4fcdae83 | 314 | */ |
3928a8a2 | 315 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 316 | |
3928a8a2 | 317 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 318 | |
4fcdae83 | 319 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 320 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 321 | |
4fcdae83 SR |
322 | /* |
323 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 324 | */ |
a8227415 | 325 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 326 | |
7e53bd42 LJ |
327 | /* |
328 | * serialize the access of the ring buffer | |
329 | * | |
330 | * ring buffer serializes readers, but it is low level protection. | |
331 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
332 | * are not protected by ring buffer. | |
333 | * | |
334 | * The content of events may become garbage if we allow other process consumes | |
335 | * these events concurrently: | |
336 | * A) the page of the consumed events may become a normal page | |
337 | * (not reader page) in ring buffer, and this page will be rewrited | |
338 | * by events producer. | |
339 | * B) The page of the consumed events may become a page for splice_read, | |
340 | * and this page will be returned to system. | |
341 | * | |
342 | * These primitives allow multi process access to different cpu ring buffer | |
343 | * concurrently. | |
344 | * | |
345 | * These primitives don't distinguish read-only and read-consume access. | |
346 | * Multi read-only access are also serialized. | |
347 | */ | |
348 | ||
349 | #ifdef CONFIG_SMP | |
350 | static DECLARE_RWSEM(all_cpu_access_lock); | |
351 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
352 | ||
353 | static inline void trace_access_lock(int cpu) | |
354 | { | |
ae3b5093 | 355 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
356 | /* gain it for accessing the whole ring buffer. */ |
357 | down_write(&all_cpu_access_lock); | |
358 | } else { | |
359 | /* gain it for accessing a cpu ring buffer. */ | |
360 | ||
ae3b5093 | 361 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
362 | down_read(&all_cpu_access_lock); |
363 | ||
364 | /* Secondly block other access to this @cpu ring buffer. */ | |
365 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
366 | } | |
367 | } | |
368 | ||
369 | static inline void trace_access_unlock(int cpu) | |
370 | { | |
ae3b5093 | 371 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
372 | up_write(&all_cpu_access_lock); |
373 | } else { | |
374 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
375 | up_read(&all_cpu_access_lock); | |
376 | } | |
377 | } | |
378 | ||
379 | static inline void trace_access_lock_init(void) | |
380 | { | |
381 | int cpu; | |
382 | ||
383 | for_each_possible_cpu(cpu) | |
384 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
385 | } | |
386 | ||
387 | #else | |
388 | ||
389 | static DEFINE_MUTEX(access_lock); | |
390 | ||
391 | static inline void trace_access_lock(int cpu) | |
392 | { | |
393 | (void)cpu; | |
394 | mutex_lock(&access_lock); | |
395 | } | |
396 | ||
397 | static inline void trace_access_unlock(int cpu) | |
398 | { | |
399 | (void)cpu; | |
400 | mutex_unlock(&access_lock); | |
401 | } | |
402 | ||
403 | static inline void trace_access_lock_init(void) | |
404 | { | |
405 | } | |
406 | ||
407 | #endif | |
408 | ||
ee6bce52 | 409 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 410 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 411 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 | 412 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
328df475 | 413 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION; |
e7e2ee89 | 414 | |
5280bcef | 415 | static void tracer_tracing_on(struct trace_array *tr) |
10246fa3 SRRH |
416 | { |
417 | if (tr->trace_buffer.buffer) | |
418 | ring_buffer_record_on(tr->trace_buffer.buffer); | |
419 | /* | |
420 | * This flag is looked at when buffers haven't been allocated | |
421 | * yet, or by some tracers (like irqsoff), that just want to | |
422 | * know if the ring buffer has been disabled, but it can handle | |
423 | * races of where it gets disabled but we still do a record. | |
424 | * As the check is in the fast path of the tracers, it is more | |
425 | * important to be fast than accurate. | |
426 | */ | |
427 | tr->buffer_disabled = 0; | |
428 | /* Make the flag seen by readers */ | |
429 | smp_wmb(); | |
430 | } | |
431 | ||
499e5470 SR |
432 | /** |
433 | * tracing_on - enable tracing buffers | |
434 | * | |
435 | * This function enables tracing buffers that may have been | |
436 | * disabled with tracing_off. | |
437 | */ | |
438 | void tracing_on(void) | |
439 | { | |
10246fa3 | 440 | tracer_tracing_on(&global_trace); |
499e5470 SR |
441 | } |
442 | EXPORT_SYMBOL_GPL(tracing_on); | |
443 | ||
09ae7234 SRRH |
444 | /** |
445 | * __trace_puts - write a constant string into the trace buffer. | |
446 | * @ip: The address of the caller | |
447 | * @str: The constant string to write | |
448 | * @size: The size of the string. | |
449 | */ | |
450 | int __trace_puts(unsigned long ip, const char *str, int size) | |
451 | { | |
452 | struct ring_buffer_event *event; | |
453 | struct ring_buffer *buffer; | |
454 | struct print_entry *entry; | |
455 | unsigned long irq_flags; | |
456 | int alloc; | |
457 | ||
458 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ | |
459 | ||
460 | local_save_flags(irq_flags); | |
461 | buffer = global_trace.trace_buffer.buffer; | |
462 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, | |
463 | irq_flags, preempt_count()); | |
464 | if (!event) | |
465 | return 0; | |
466 | ||
467 | entry = ring_buffer_event_data(event); | |
468 | entry->ip = ip; | |
469 | ||
470 | memcpy(&entry->buf, str, size); | |
471 | ||
472 | /* Add a newline if necessary */ | |
473 | if (entry->buf[size - 1] != '\n') { | |
474 | entry->buf[size] = '\n'; | |
475 | entry->buf[size + 1] = '\0'; | |
476 | } else | |
477 | entry->buf[size] = '\0'; | |
478 | ||
479 | __buffer_unlock_commit(buffer, event); | |
480 | ||
481 | return size; | |
482 | } | |
483 | EXPORT_SYMBOL_GPL(__trace_puts); | |
484 | ||
485 | /** | |
486 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
487 | * @ip: The address of the caller | |
488 | * @str: The constant string to write to the buffer to | |
489 | */ | |
490 | int __trace_bputs(unsigned long ip, const char *str) | |
491 | { | |
492 | struct ring_buffer_event *event; | |
493 | struct ring_buffer *buffer; | |
494 | struct bputs_entry *entry; | |
495 | unsigned long irq_flags; | |
496 | int size = sizeof(struct bputs_entry); | |
497 | ||
498 | local_save_flags(irq_flags); | |
499 | buffer = global_trace.trace_buffer.buffer; | |
500 | event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, | |
501 | irq_flags, preempt_count()); | |
502 | if (!event) | |
503 | return 0; | |
504 | ||
505 | entry = ring_buffer_event_data(event); | |
506 | entry->ip = ip; | |
507 | entry->str = str; | |
508 | ||
509 | __buffer_unlock_commit(buffer, event); | |
510 | ||
511 | return 1; | |
512 | } | |
513 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
514 | ||
ad909e21 SRRH |
515 | #ifdef CONFIG_TRACER_SNAPSHOT |
516 | /** | |
517 | * trace_snapshot - take a snapshot of the current buffer. | |
518 | * | |
519 | * This causes a swap between the snapshot buffer and the current live | |
520 | * tracing buffer. You can use this to take snapshots of the live | |
521 | * trace when some condition is triggered, but continue to trace. | |
522 | * | |
523 | * Note, make sure to allocate the snapshot with either | |
524 | * a tracing_snapshot_alloc(), or by doing it manually | |
525 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
526 | * | |
527 | * If the snapshot buffer is not allocated, it will stop tracing. | |
528 | * Basically making a permanent snapshot. | |
529 | */ | |
530 | void tracing_snapshot(void) | |
531 | { | |
532 | struct trace_array *tr = &global_trace; | |
533 | struct tracer *tracer = tr->current_trace; | |
534 | unsigned long flags; | |
535 | ||
1b22e382 SRRH |
536 | if (in_nmi()) { |
537 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
538 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
539 | return; | |
540 | } | |
541 | ||
ad909e21 | 542 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
543 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
544 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
545 | tracing_off(); |
546 | return; | |
547 | } | |
548 | ||
549 | /* Note, snapshot can not be used when the tracer uses it */ | |
550 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
551 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
552 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
553 | return; |
554 | } | |
555 | ||
556 | local_irq_save(flags); | |
557 | update_max_tr(tr, current, smp_processor_id()); | |
558 | local_irq_restore(flags); | |
559 | } | |
1b22e382 | 560 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
561 | |
562 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
563 | struct trace_buffer *size_buf, int cpu_id); | |
3209cff4 SRRH |
564 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); |
565 | ||
566 | static int alloc_snapshot(struct trace_array *tr) | |
567 | { | |
568 | int ret; | |
569 | ||
570 | if (!tr->allocated_snapshot) { | |
571 | ||
572 | /* allocate spare buffer */ | |
573 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
574 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
575 | if (ret < 0) | |
576 | return ret; | |
577 | ||
578 | tr->allocated_snapshot = true; | |
579 | } | |
580 | ||
581 | return 0; | |
582 | } | |
583 | ||
584 | void free_snapshot(struct trace_array *tr) | |
585 | { | |
586 | /* | |
587 | * We don't free the ring buffer. instead, resize it because | |
588 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
589 | * we want preserve it. | |
590 | */ | |
591 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
592 | set_buffer_entries(&tr->max_buffer, 1); | |
593 | tracing_reset_online_cpus(&tr->max_buffer); | |
594 | tr->allocated_snapshot = false; | |
595 | } | |
ad909e21 SRRH |
596 | |
597 | /** | |
598 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
599 | * | |
600 | * This is similar to trace_snapshot(), but it will allocate the | |
601 | * snapshot buffer if it isn't already allocated. Use this only | |
602 | * where it is safe to sleep, as the allocation may sleep. | |
603 | * | |
604 | * This causes a swap between the snapshot buffer and the current live | |
605 | * tracing buffer. You can use this to take snapshots of the live | |
606 | * trace when some condition is triggered, but continue to trace. | |
607 | */ | |
608 | void tracing_snapshot_alloc(void) | |
609 | { | |
610 | struct trace_array *tr = &global_trace; | |
611 | int ret; | |
612 | ||
3209cff4 SRRH |
613 | ret = alloc_snapshot(tr); |
614 | if (WARN_ON(ret < 0)) | |
615 | return; | |
ad909e21 SRRH |
616 | |
617 | tracing_snapshot(); | |
618 | } | |
1b22e382 | 619 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
620 | #else |
621 | void tracing_snapshot(void) | |
622 | { | |
623 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
624 | } | |
1b22e382 | 625 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
626 | void tracing_snapshot_alloc(void) |
627 | { | |
628 | /* Give warning */ | |
629 | tracing_snapshot(); | |
630 | } | |
1b22e382 | 631 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
632 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
633 | ||
5280bcef | 634 | static void tracer_tracing_off(struct trace_array *tr) |
10246fa3 SRRH |
635 | { |
636 | if (tr->trace_buffer.buffer) | |
637 | ring_buffer_record_off(tr->trace_buffer.buffer); | |
638 | /* | |
639 | * This flag is looked at when buffers haven't been allocated | |
640 | * yet, or by some tracers (like irqsoff), that just want to | |
641 | * know if the ring buffer has been disabled, but it can handle | |
642 | * races of where it gets disabled but we still do a record. | |
643 | * As the check is in the fast path of the tracers, it is more | |
644 | * important to be fast than accurate. | |
645 | */ | |
646 | tr->buffer_disabled = 1; | |
647 | /* Make the flag seen by readers */ | |
648 | smp_wmb(); | |
649 | } | |
650 | ||
499e5470 SR |
651 | /** |
652 | * tracing_off - turn off tracing buffers | |
653 | * | |
654 | * This function stops the tracing buffers from recording data. | |
655 | * It does not disable any overhead the tracers themselves may | |
656 | * be causing. This function simply causes all recording to | |
657 | * the ring buffers to fail. | |
658 | */ | |
659 | void tracing_off(void) | |
660 | { | |
10246fa3 | 661 | tracer_tracing_off(&global_trace); |
499e5470 SR |
662 | } |
663 | EXPORT_SYMBOL_GPL(tracing_off); | |
664 | ||
de7edd31 SRRH |
665 | void disable_trace_on_warning(void) |
666 | { | |
667 | if (__disable_trace_on_warning) | |
668 | tracing_off(); | |
669 | } | |
670 | ||
10246fa3 SRRH |
671 | /** |
672 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
673 | * @tr : the trace array to know if ring buffer is enabled | |
674 | * | |
675 | * Shows real state of the ring buffer if it is enabled or not. | |
676 | */ | |
5280bcef | 677 | static int tracer_tracing_is_on(struct trace_array *tr) |
10246fa3 SRRH |
678 | { |
679 | if (tr->trace_buffer.buffer) | |
680 | return ring_buffer_record_is_on(tr->trace_buffer.buffer); | |
681 | return !tr->buffer_disabled; | |
682 | } | |
683 | ||
499e5470 SR |
684 | /** |
685 | * tracing_is_on - show state of ring buffers enabled | |
686 | */ | |
687 | int tracing_is_on(void) | |
688 | { | |
10246fa3 | 689 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
690 | } |
691 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
692 | ||
3928a8a2 | 693 | static int __init set_buf_size(char *str) |
bc0c38d1 | 694 | { |
3928a8a2 | 695 | unsigned long buf_size; |
c6caeeb1 | 696 | |
bc0c38d1 SR |
697 | if (!str) |
698 | return 0; | |
9d612bef | 699 | buf_size = memparse(str, &str); |
c6caeeb1 | 700 | /* nr_entries can not be zero */ |
9d612bef | 701 | if (buf_size == 0) |
c6caeeb1 | 702 | return 0; |
3928a8a2 | 703 | trace_buf_size = buf_size; |
bc0c38d1 SR |
704 | return 1; |
705 | } | |
3928a8a2 | 706 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 707 | |
0e950173 TB |
708 | static int __init set_tracing_thresh(char *str) |
709 | { | |
87abb3b1 | 710 | unsigned long threshold; |
0e950173 TB |
711 | int ret; |
712 | ||
713 | if (!str) | |
714 | return 0; | |
bcd83ea6 | 715 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
716 | if (ret < 0) |
717 | return 0; | |
87abb3b1 | 718 | tracing_thresh = threshold * 1000; |
0e950173 TB |
719 | return 1; |
720 | } | |
721 | __setup("tracing_thresh=", set_tracing_thresh); | |
722 | ||
57f50be1 SR |
723 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
724 | { | |
725 | return nsecs / 1000; | |
726 | } | |
727 | ||
4fcdae83 | 728 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
729 | static const char *trace_options[] = { |
730 | "print-parent", | |
731 | "sym-offset", | |
732 | "sym-addr", | |
733 | "verbose", | |
f9896bf3 | 734 | "raw", |
5e3ca0ec | 735 | "hex", |
cb0f12aa | 736 | "bin", |
2a2cc8f7 | 737 | "block", |
86387f7e | 738 | "stacktrace", |
5e1607a0 | 739 | "trace_printk", |
b2a866f9 | 740 | "ftrace_preempt", |
9f029e83 | 741 | "branch", |
12ef7d44 | 742 | "annotate", |
02b67518 | 743 | "userstacktrace", |
b54d3de9 | 744 | "sym-userobj", |
66896a85 | 745 | "printk-msg-only", |
c4a8e8be | 746 | "context-info", |
c032ef64 | 747 | "latency-format", |
be6f164a | 748 | "sleep-time", |
a2a16d6a | 749 | "graph-time", |
e870e9a1 | 750 | "record-cmd", |
750912fa | 751 | "overwrite", |
cf30cf67 | 752 | "disable_on_free", |
77271ce4 | 753 | "irq-info", |
5224c3a3 | 754 | "markers", |
328df475 | 755 | "function-trace", |
bc0c38d1 SR |
756 | NULL |
757 | }; | |
758 | ||
5079f326 Z |
759 | static struct { |
760 | u64 (*func)(void); | |
761 | const char *name; | |
8be0709f | 762 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 763 | } trace_clocks[] = { |
8be0709f DS |
764 | { trace_clock_local, "local", 1 }, |
765 | { trace_clock_global, "global", 1 }, | |
766 | { trace_clock_counter, "counter", 0 }, | |
8aacf017 | 767 | { trace_clock_jiffies, "uptime", 1 }, |
76f11917 | 768 | { trace_clock, "perf", 1 }, |
8cbd9cc6 | 769 | ARCH_TRACE_CLOCKS |
5079f326 Z |
770 | }; |
771 | ||
b63f39ea | 772 | /* |
773 | * trace_parser_get_init - gets the buffer for trace parser | |
774 | */ | |
775 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
776 | { | |
777 | memset(parser, 0, sizeof(*parser)); | |
778 | ||
779 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
780 | if (!parser->buffer) | |
781 | return 1; | |
782 | ||
783 | parser->size = size; | |
784 | return 0; | |
785 | } | |
786 | ||
787 | /* | |
788 | * trace_parser_put - frees the buffer for trace parser | |
789 | */ | |
790 | void trace_parser_put(struct trace_parser *parser) | |
791 | { | |
792 | kfree(parser->buffer); | |
793 | } | |
794 | ||
795 | /* | |
796 | * trace_get_user - reads the user input string separated by space | |
797 | * (matched by isspace(ch)) | |
798 | * | |
799 | * For each string found the 'struct trace_parser' is updated, | |
800 | * and the function returns. | |
801 | * | |
802 | * Returns number of bytes read. | |
803 | * | |
804 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
805 | */ | |
806 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
807 | size_t cnt, loff_t *ppos) | |
808 | { | |
809 | char ch; | |
810 | size_t read = 0; | |
811 | ssize_t ret; | |
812 | ||
813 | if (!*ppos) | |
814 | trace_parser_clear(parser); | |
815 | ||
816 | ret = get_user(ch, ubuf++); | |
817 | if (ret) | |
818 | goto out; | |
819 | ||
820 | read++; | |
821 | cnt--; | |
822 | ||
823 | /* | |
824 | * The parser is not finished with the last write, | |
825 | * continue reading the user input without skipping spaces. | |
826 | */ | |
827 | if (!parser->cont) { | |
828 | /* skip white space */ | |
829 | while (cnt && isspace(ch)) { | |
830 | ret = get_user(ch, ubuf++); | |
831 | if (ret) | |
832 | goto out; | |
833 | read++; | |
834 | cnt--; | |
835 | } | |
836 | ||
837 | /* only spaces were written */ | |
838 | if (isspace(ch)) { | |
839 | *ppos += read; | |
840 | ret = read; | |
841 | goto out; | |
842 | } | |
843 | ||
844 | parser->idx = 0; | |
845 | } | |
846 | ||
847 | /* read the non-space input */ | |
848 | while (cnt && !isspace(ch)) { | |
3c235a33 | 849 | if (parser->idx < parser->size - 1) |
b63f39ea | 850 | parser->buffer[parser->idx++] = ch; |
851 | else { | |
852 | ret = -EINVAL; | |
853 | goto out; | |
854 | } | |
855 | ret = get_user(ch, ubuf++); | |
856 | if (ret) | |
857 | goto out; | |
858 | read++; | |
859 | cnt--; | |
860 | } | |
861 | ||
862 | /* We either got finished input or we have to wait for another call. */ | |
863 | if (isspace(ch)) { | |
864 | parser->buffer[parser->idx] = 0; | |
865 | parser->cont = false; | |
057db848 | 866 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 867 | parser->cont = true; |
868 | parser->buffer[parser->idx++] = ch; | |
057db848 SR |
869 | } else { |
870 | ret = -EINVAL; | |
871 | goto out; | |
b63f39ea | 872 | } |
873 | ||
874 | *ppos += read; | |
875 | ret = read; | |
876 | ||
877 | out: | |
878 | return ret; | |
879 | } | |
880 | ||
6c6c2796 PP |
881 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
882 | { | |
883 | int len; | |
884 | int ret; | |
885 | ||
2dc5d12b SR |
886 | if (!cnt) |
887 | return 0; | |
888 | ||
6c6c2796 PP |
889 | if (s->len <= s->readpos) |
890 | return -EBUSY; | |
891 | ||
892 | len = s->len - s->readpos; | |
893 | if (cnt > len) | |
894 | cnt = len; | |
895 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 896 | if (ret == cnt) |
6c6c2796 PP |
897 | return -EFAULT; |
898 | ||
2dc5d12b SR |
899 | cnt -= ret; |
900 | ||
e74da523 | 901 | s->readpos += cnt; |
6c6c2796 | 902 | return cnt; |
214023c3 SR |
903 | } |
904 | ||
b8b94265 | 905 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
906 | { |
907 | int len; | |
3c56819b EGM |
908 | |
909 | if (s->len <= s->readpos) | |
910 | return -EBUSY; | |
911 | ||
912 | len = s->len - s->readpos; | |
913 | if (cnt > len) | |
914 | cnt = len; | |
5a26c8f0 | 915 | memcpy(buf, s->buffer + s->readpos, cnt); |
3c56819b | 916 | |
e74da523 | 917 | s->readpos += cnt; |
3c56819b EGM |
918 | return cnt; |
919 | } | |
920 | ||
5d4a9dba SR |
921 | /* |
922 | * ftrace_max_lock is used to protect the swapping of buffers | |
923 | * when taking a max snapshot. The buffers themselves are | |
924 | * protected by per_cpu spinlocks. But the action of the swap | |
925 | * needs its own lock. | |
926 | * | |
445c8951 | 927 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
928 | * with performance when lockdep debugging is enabled. |
929 | * | |
930 | * It is also used in other places outside the update_max_tr | |
931 | * so it needs to be defined outside of the | |
932 | * CONFIG_TRACER_MAX_TRACE. | |
933 | */ | |
445c8951 | 934 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 935 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba | 936 | |
0e950173 TB |
937 | unsigned long __read_mostly tracing_thresh; |
938 | ||
5d4a9dba SR |
939 | #ifdef CONFIG_TRACER_MAX_TRACE |
940 | unsigned long __read_mostly tracing_max_latency; | |
5d4a9dba SR |
941 | |
942 | /* | |
943 | * Copy the new maximum trace into the separate maximum-trace | |
944 | * structure. (this way the maximum trace is permanently saved, | |
945 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
946 | */ | |
947 | static void | |
948 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
949 | { | |
12883efb SRRH |
950 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
951 | struct trace_buffer *max_buf = &tr->max_buffer; | |
952 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
953 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 954 | |
12883efb SRRH |
955 | max_buf->cpu = cpu; |
956 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 957 | |
8248ac05 SR |
958 | max_data->saved_latency = tracing_max_latency; |
959 | max_data->critical_start = data->critical_start; | |
960 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 961 | |
1acaa1b2 | 962 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 963 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
964 | /* |
965 | * If tsk == current, then use current_uid(), as that does not use | |
966 | * RCU. The irq tracer can be called out of RCU scope. | |
967 | */ | |
968 | if (tsk == current) | |
969 | max_data->uid = current_uid(); | |
970 | else | |
971 | max_data->uid = task_uid(tsk); | |
972 | ||
8248ac05 SR |
973 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
974 | max_data->policy = tsk->policy; | |
975 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
976 | |
977 | /* record this tasks comm */ | |
978 | tracing_record_cmdline(tsk); | |
979 | } | |
980 | ||
4fcdae83 SR |
981 | /** |
982 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
983 | * @tr: tracer | |
984 | * @tsk: the task with the latency | |
985 | * @cpu: The cpu that initiated the trace. | |
986 | * | |
987 | * Flip the buffers between the @tr and the max_tr and record information | |
988 | * about which task was the cause of this latency. | |
989 | */ | |
e309b41d | 990 | void |
bc0c38d1 SR |
991 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
992 | { | |
2721e72d | 993 | struct ring_buffer *buf; |
bc0c38d1 | 994 | |
2b6080f2 | 995 | if (tr->stop_count) |
b8de7bd1 SR |
996 | return; |
997 | ||
4c11d7ae | 998 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 999 | |
45ad21ca | 1000 | if (!tr->allocated_snapshot) { |
debdd57f | 1001 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 1002 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 1003 | return; |
debdd57f | 1004 | } |
34600f0e | 1005 | |
0199c4e6 | 1006 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 | 1007 | |
12883efb SRRH |
1008 | buf = tr->trace_buffer.buffer; |
1009 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
1010 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 1011 | |
bc0c38d1 | 1012 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 1013 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
1014 | } |
1015 | ||
1016 | /** | |
1017 | * update_max_tr_single - only copy one trace over, and reset the rest | |
1018 | * @tr - tracer | |
1019 | * @tsk - task with the latency | |
1020 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
1021 | * |
1022 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1023 | */ |
e309b41d | 1024 | void |
bc0c38d1 SR |
1025 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1026 | { | |
3928a8a2 | 1027 | int ret; |
bc0c38d1 | 1028 | |
2b6080f2 | 1029 | if (tr->stop_count) |
b8de7bd1 SR |
1030 | return; |
1031 | ||
4c11d7ae | 1032 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1033 | if (!tr->allocated_snapshot) { |
2930e04d | 1034 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1035 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1036 | return; |
2930e04d | 1037 | } |
ef710e10 | 1038 | |
0199c4e6 | 1039 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 1040 | |
12883efb | 1041 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 1042 | |
e8165dbb SR |
1043 | if (ret == -EBUSY) { |
1044 | /* | |
1045 | * We failed to swap the buffer due to a commit taking | |
1046 | * place on this CPU. We fail to record, but we reset | |
1047 | * the max trace buffer (no one writes directly to it) | |
1048 | * and flag that it failed. | |
1049 | */ | |
12883efb | 1050 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1051 | "Failed to swap buffers due to commit in progress\n"); |
1052 | } | |
1053 | ||
e8165dbb | 1054 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1055 | |
1056 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 1057 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 1058 | } |
5d4a9dba | 1059 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1060 | |
0d5c6e1c SR |
1061 | static void default_wait_pipe(struct trace_iterator *iter) |
1062 | { | |
15693458 SRRH |
1063 | /* Iterators are static, they should be filled or empty */ |
1064 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
1065 | return; | |
0d5c6e1c | 1066 | |
12883efb | 1067 | ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file); |
0d5c6e1c SR |
1068 | } |
1069 | ||
f4e781c0 SRRH |
1070 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
1071 | static int run_tracer_selftest(struct tracer *type) | |
1072 | { | |
1073 | struct trace_array *tr = &global_trace; | |
1074 | struct tracer *saved_tracer = tr->current_trace; | |
1075 | int ret; | |
0d5c6e1c | 1076 | |
f4e781c0 SRRH |
1077 | if (!type->selftest || tracing_selftest_disabled) |
1078 | return 0; | |
0d5c6e1c SR |
1079 | |
1080 | /* | |
f4e781c0 SRRH |
1081 | * Run a selftest on this tracer. |
1082 | * Here we reset the trace buffer, and set the current | |
1083 | * tracer to be this tracer. The tracer can then run some | |
1084 | * internal tracing to verify that everything is in order. | |
1085 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1086 | */ |
f4e781c0 | 1087 | tracing_reset_online_cpus(&tr->trace_buffer); |
0d5c6e1c | 1088 | |
f4e781c0 SRRH |
1089 | tr->current_trace = type; |
1090 | ||
1091 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1092 | if (type->use_max_tr) { | |
1093 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1094 | if (ring_buffer_expanded) | |
1095 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1096 | RING_BUFFER_ALL_CPUS); | |
1097 | tr->allocated_snapshot = true; | |
1098 | } | |
1099 | #endif | |
1100 | ||
1101 | /* the test is responsible for initializing and enabling */ | |
1102 | pr_info("Testing tracer %s: ", type->name); | |
1103 | ret = type->selftest(type, tr); | |
1104 | /* the test is responsible for resetting too */ | |
1105 | tr->current_trace = saved_tracer; | |
1106 | if (ret) { | |
1107 | printk(KERN_CONT "FAILED!\n"); | |
1108 | /* Add the warning after printing 'FAILED' */ | |
1109 | WARN_ON(1); | |
1110 | return -1; | |
1111 | } | |
1112 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1113 | tracing_reset_online_cpus(&tr->trace_buffer); | |
1114 | ||
1115 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1116 | if (type->use_max_tr) { | |
1117 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1118 | |
f4e781c0 SRRH |
1119 | /* Shrink the max buffer again */ |
1120 | if (ring_buffer_expanded) | |
1121 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1122 | RING_BUFFER_ALL_CPUS); | |
1123 | } | |
1124 | #endif | |
1125 | ||
1126 | printk(KERN_CONT "PASSED\n"); | |
1127 | return 0; | |
1128 | } | |
1129 | #else | |
1130 | static inline int run_tracer_selftest(struct tracer *type) | |
1131 | { | |
1132 | return 0; | |
0d5c6e1c | 1133 | } |
f4e781c0 | 1134 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 1135 | |
4fcdae83 SR |
1136 | /** |
1137 | * register_tracer - register a tracer with the ftrace system. | |
1138 | * @type - the plugin for the tracer | |
1139 | * | |
1140 | * Register a new plugin tracer. | |
1141 | */ | |
bc0c38d1 SR |
1142 | int register_tracer(struct tracer *type) |
1143 | { | |
1144 | struct tracer *t; | |
bc0c38d1 SR |
1145 | int ret = 0; |
1146 | ||
1147 | if (!type->name) { | |
1148 | pr_info("Tracer must have a name\n"); | |
1149 | return -1; | |
1150 | } | |
1151 | ||
24a461d5 | 1152 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
1153 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
1154 | return -1; | |
1155 | } | |
1156 | ||
bc0c38d1 | 1157 | mutex_lock(&trace_types_lock); |
86fa2f60 | 1158 | |
8e1b82e0 FW |
1159 | tracing_selftest_running = true; |
1160 | ||
bc0c38d1 SR |
1161 | for (t = trace_types; t; t = t->next) { |
1162 | if (strcmp(type->name, t->name) == 0) { | |
1163 | /* already found */ | |
ee6c2c1b | 1164 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
1165 | type->name); |
1166 | ret = -1; | |
1167 | goto out; | |
1168 | } | |
1169 | } | |
1170 | ||
adf9f195 FW |
1171 | if (!type->set_flag) |
1172 | type->set_flag = &dummy_set_flag; | |
1173 | if (!type->flags) | |
1174 | type->flags = &dummy_tracer_flags; | |
1175 | else | |
1176 | if (!type->flags->opts) | |
1177 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
1178 | if (!type->wait_pipe) |
1179 | type->wait_pipe = default_wait_pipe; | |
1180 | ||
f4e781c0 SRRH |
1181 | ret = run_tracer_selftest(type); |
1182 | if (ret < 0) | |
1183 | goto out; | |
60a11774 | 1184 | |
bc0c38d1 SR |
1185 | type->next = trace_types; |
1186 | trace_types = type; | |
60a11774 | 1187 | |
bc0c38d1 | 1188 | out: |
8e1b82e0 | 1189 | tracing_selftest_running = false; |
bc0c38d1 SR |
1190 | mutex_unlock(&trace_types_lock); |
1191 | ||
dac74940 SR |
1192 | if (ret || !default_bootup_tracer) |
1193 | goto out_unlock; | |
1194 | ||
ee6c2c1b | 1195 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1196 | goto out_unlock; |
1197 | ||
1198 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1199 | /* Do we want this tracer to start on bootup? */ | |
1200 | tracing_set_tracer(type->name); | |
1201 | default_bootup_tracer = NULL; | |
1202 | /* disable other selftests, since this will break it. */ | |
55034cd6 | 1203 | tracing_selftest_disabled = true; |
b2821ae6 | 1204 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1205 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1206 | type->name); | |
b2821ae6 | 1207 | #endif |
b2821ae6 | 1208 | |
dac74940 | 1209 | out_unlock: |
bc0c38d1 SR |
1210 | return ret; |
1211 | } | |
1212 | ||
12883efb | 1213 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1214 | { |
12883efb | 1215 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1216 | |
a5416411 HT |
1217 | if (!buffer) |
1218 | return; | |
1219 | ||
f633903a SR |
1220 | ring_buffer_record_disable(buffer); |
1221 | ||
1222 | /* Make sure all commits have finished */ | |
1223 | synchronize_sched(); | |
68179686 | 1224 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1225 | |
1226 | ring_buffer_record_enable(buffer); | |
1227 | } | |
1228 | ||
12883efb | 1229 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1230 | { |
12883efb | 1231 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1232 | int cpu; |
1233 | ||
a5416411 HT |
1234 | if (!buffer) |
1235 | return; | |
1236 | ||
621968cd SR |
1237 | ring_buffer_record_disable(buffer); |
1238 | ||
1239 | /* Make sure all commits have finished */ | |
1240 | synchronize_sched(); | |
1241 | ||
9457158b | 1242 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 PE |
1243 | |
1244 | for_each_online_cpu(cpu) | |
68179686 | 1245 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1246 | |
1247 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1248 | } |
1249 | ||
09d8091c | 1250 | /* Must have trace_types_lock held */ |
873c642f | 1251 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1252 | { |
873c642f SRRH |
1253 | struct trace_array *tr; |
1254 | ||
873c642f | 1255 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
12883efb SRRH |
1256 | tracing_reset_online_cpus(&tr->trace_buffer); |
1257 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1258 | tracing_reset_online_cpus(&tr->max_buffer); | |
1259 | #endif | |
873c642f | 1260 | } |
9456f0fa SR |
1261 | } |
1262 | ||
bc0c38d1 | 1263 | #define SAVED_CMDLINES 128 |
2c7eea4c | 1264 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
1265 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
1266 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
1267 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
1268 | static int cmdline_idx; | |
edc35bd7 | 1269 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 1270 | |
25b0b44a | 1271 | /* temporary disable recording */ |
4fd27358 | 1272 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
1273 | |
1274 | static void trace_init_cmdlines(void) | |
1275 | { | |
2c7eea4c TG |
1276 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
1277 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
1278 | cmdline_idx = 0; |
1279 | } | |
1280 | ||
b5130b1e CE |
1281 | int is_tracing_stopped(void) |
1282 | { | |
2b6080f2 | 1283 | return global_trace.stop_count; |
b5130b1e CE |
1284 | } |
1285 | ||
69bb54ec SR |
1286 | /** |
1287 | * ftrace_off_permanent - disable all ftrace code permanently | |
1288 | * | |
1289 | * This should only be called when a serious anomally has | |
1290 | * been detected. This will turn off the function tracing, | |
1291 | * ring buffers, and other tracing utilites. It takes no | |
1292 | * locks and can be called from any context. | |
1293 | */ | |
1294 | void ftrace_off_permanent(void) | |
1295 | { | |
1296 | tracing_disabled = 1; | |
1297 | ftrace_stop(); | |
1298 | tracing_off_permanent(); | |
1299 | } | |
1300 | ||
0f048701 SR |
1301 | /** |
1302 | * tracing_start - quick start of the tracer | |
1303 | * | |
1304 | * If tracing is enabled but was stopped by tracing_stop, | |
1305 | * this will start the tracer back up. | |
1306 | */ | |
1307 | void tracing_start(void) | |
1308 | { | |
1309 | struct ring_buffer *buffer; | |
1310 | unsigned long flags; | |
1311 | ||
1312 | if (tracing_disabled) | |
1313 | return; | |
1314 | ||
2b6080f2 SR |
1315 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1316 | if (--global_trace.stop_count) { | |
1317 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1318 | /* Someone screwed up their debugging */ |
1319 | WARN_ON_ONCE(1); | |
2b6080f2 | 1320 | global_trace.stop_count = 0; |
b06a8301 | 1321 | } |
0f048701 SR |
1322 | goto out; |
1323 | } | |
1324 | ||
a2f80714 SR |
1325 | /* Prevent the buffers from switching */ |
1326 | arch_spin_lock(&ftrace_max_lock); | |
0f048701 | 1327 | |
12883efb | 1328 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1329 | if (buffer) |
1330 | ring_buffer_record_enable(buffer); | |
1331 | ||
12883efb SRRH |
1332 | #ifdef CONFIG_TRACER_MAX_TRACE |
1333 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1334 | if (buffer) |
1335 | ring_buffer_record_enable(buffer); | |
12883efb | 1336 | #endif |
0f048701 | 1337 | |
a2f80714 SR |
1338 | arch_spin_unlock(&ftrace_max_lock); |
1339 | ||
0f048701 SR |
1340 | ftrace_start(); |
1341 | out: | |
2b6080f2 SR |
1342 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1343 | } | |
1344 | ||
1345 | static void tracing_start_tr(struct trace_array *tr) | |
1346 | { | |
1347 | struct ring_buffer *buffer; | |
1348 | unsigned long flags; | |
1349 | ||
1350 | if (tracing_disabled) | |
1351 | return; | |
1352 | ||
1353 | /* If global, we need to also start the max tracer */ | |
1354 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1355 | return tracing_start(); | |
1356 | ||
1357 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1358 | ||
1359 | if (--tr->stop_count) { | |
1360 | if (tr->stop_count < 0) { | |
1361 | /* Someone screwed up their debugging */ | |
1362 | WARN_ON_ONCE(1); | |
1363 | tr->stop_count = 0; | |
1364 | } | |
1365 | goto out; | |
1366 | } | |
1367 | ||
12883efb | 1368 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1369 | if (buffer) |
1370 | ring_buffer_record_enable(buffer); | |
1371 | ||
1372 | out: | |
1373 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1374 | } |
1375 | ||
1376 | /** | |
1377 | * tracing_stop - quick stop of the tracer | |
1378 | * | |
1379 | * Light weight way to stop tracing. Use in conjunction with | |
1380 | * tracing_start. | |
1381 | */ | |
1382 | void tracing_stop(void) | |
1383 | { | |
1384 | struct ring_buffer *buffer; | |
1385 | unsigned long flags; | |
1386 | ||
1387 | ftrace_stop(); | |
2b6080f2 SR |
1388 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1389 | if (global_trace.stop_count++) | |
0f048701 SR |
1390 | goto out; |
1391 | ||
a2f80714 SR |
1392 | /* Prevent the buffers from switching */ |
1393 | arch_spin_lock(&ftrace_max_lock); | |
1394 | ||
12883efb | 1395 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1396 | if (buffer) |
1397 | ring_buffer_record_disable(buffer); | |
1398 | ||
12883efb SRRH |
1399 | #ifdef CONFIG_TRACER_MAX_TRACE |
1400 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1401 | if (buffer) |
1402 | ring_buffer_record_disable(buffer); | |
12883efb | 1403 | #endif |
0f048701 | 1404 | |
a2f80714 SR |
1405 | arch_spin_unlock(&ftrace_max_lock); |
1406 | ||
0f048701 | 1407 | out: |
2b6080f2 SR |
1408 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1409 | } | |
1410 | ||
1411 | static void tracing_stop_tr(struct trace_array *tr) | |
1412 | { | |
1413 | struct ring_buffer *buffer; | |
1414 | unsigned long flags; | |
1415 | ||
1416 | /* If global, we need to also stop the max tracer */ | |
1417 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1418 | return tracing_stop(); | |
1419 | ||
1420 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1421 | if (tr->stop_count++) | |
1422 | goto out; | |
1423 | ||
12883efb | 1424 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1425 | if (buffer) |
1426 | ring_buffer_record_disable(buffer); | |
1427 | ||
1428 | out: | |
1429 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1430 | } |
1431 | ||
e309b41d | 1432 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1433 | |
e309b41d | 1434 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1435 | { |
a635cf04 | 1436 | unsigned pid, idx; |
bc0c38d1 SR |
1437 | |
1438 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
1439 | return; | |
1440 | ||
1441 | /* | |
1442 | * It's not the end of the world if we don't get | |
1443 | * the lock, but we also don't want to spin | |
1444 | * nor do we want to disable interrupts, | |
1445 | * so if we miss here, then better luck next time. | |
1446 | */ | |
0199c4e6 | 1447 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
1448 | return; |
1449 | ||
1450 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1451 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1452 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1453 | ||
a635cf04 CE |
1454 | /* |
1455 | * Check whether the cmdline buffer at idx has a pid | |
1456 | * mapped. We are going to overwrite that entry so we | |
1457 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1458 | * would read the new comm for the old pid. | |
1459 | */ | |
1460 | pid = map_cmdline_to_pid[idx]; | |
1461 | if (pid != NO_CMDLINE_MAP) | |
1462 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1463 | |
a635cf04 | 1464 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1465 | map_pid_to_cmdline[tsk->pid] = idx; |
1466 | ||
1467 | cmdline_idx = idx; | |
1468 | } | |
1469 | ||
1470 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1471 | ||
0199c4e6 | 1472 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1473 | } |
1474 | ||
4ca53085 | 1475 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1476 | { |
bc0c38d1 SR |
1477 | unsigned map; |
1478 | ||
4ca53085 SR |
1479 | if (!pid) { |
1480 | strcpy(comm, "<idle>"); | |
1481 | return; | |
1482 | } | |
bc0c38d1 | 1483 | |
74bf4076 SR |
1484 | if (WARN_ON_ONCE(pid < 0)) { |
1485 | strcpy(comm, "<XXX>"); | |
1486 | return; | |
1487 | } | |
1488 | ||
4ca53085 SR |
1489 | if (pid > PID_MAX_DEFAULT) { |
1490 | strcpy(comm, "<...>"); | |
1491 | return; | |
1492 | } | |
bc0c38d1 | 1493 | |
5b6045a9 | 1494 | preempt_disable(); |
0199c4e6 | 1495 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1496 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1497 | if (map != NO_CMDLINE_MAP) |
1498 | strcpy(comm, saved_cmdlines[map]); | |
1499 | else | |
1500 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1501 | |
0199c4e6 | 1502 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1503 | preempt_enable(); |
bc0c38d1 SR |
1504 | } |
1505 | ||
e309b41d | 1506 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1507 | { |
0fb9656d | 1508 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1509 | return; |
1510 | ||
7ffbd48d SR |
1511 | if (!__this_cpu_read(trace_cmdline_save)) |
1512 | return; | |
1513 | ||
1514 | __this_cpu_write(trace_cmdline_save, false); | |
1515 | ||
bc0c38d1 SR |
1516 | trace_save_cmdline(tsk); |
1517 | } | |
1518 | ||
45dcd8b8 | 1519 | void |
38697053 SR |
1520 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1521 | int pc) | |
bc0c38d1 SR |
1522 | { |
1523 | struct task_struct *tsk = current; | |
bc0c38d1 | 1524 | |
777e208d SR |
1525 | entry->preempt_count = pc & 0xff; |
1526 | entry->pid = (tsk) ? tsk->pid : 0; | |
1527 | entry->flags = | |
9244489a | 1528 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1529 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1530 | #else |
1531 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1532 | #endif | |
bc0c38d1 SR |
1533 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1534 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1535 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1536 | } | |
f413cdb8 | 1537 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1538 | |
e77405ad SR |
1539 | struct ring_buffer_event * |
1540 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1541 | int type, | |
1542 | unsigned long len, | |
1543 | unsigned long flags, int pc) | |
51a763dd ACM |
1544 | { |
1545 | struct ring_buffer_event *event; | |
1546 | ||
e77405ad | 1547 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1548 | if (event != NULL) { |
1549 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1550 | ||
1551 | tracing_generic_entry_update(ent, flags, pc); | |
1552 | ent->type = type; | |
1553 | } | |
1554 | ||
1555 | return event; | |
1556 | } | |
51a763dd | 1557 | |
7ffbd48d SR |
1558 | void |
1559 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1560 | { | |
1561 | __this_cpu_write(trace_cmdline_save, true); | |
1562 | ring_buffer_unlock_commit(buffer, event); | |
1563 | } | |
1564 | ||
e77405ad SR |
1565 | static inline void |
1566 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1567 | struct ring_buffer_event *event, | |
0d5c6e1c | 1568 | unsigned long flags, int pc) |
51a763dd | 1569 | { |
7ffbd48d | 1570 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1571 | |
e77405ad SR |
1572 | ftrace_trace_stack(buffer, flags, 6, pc); |
1573 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1574 | } |
1575 | ||
e77405ad SR |
1576 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1577 | struct ring_buffer_event *event, | |
1578 | unsigned long flags, int pc) | |
07edf712 | 1579 | { |
0d5c6e1c | 1580 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
51a763dd | 1581 | } |
0d5c6e1c | 1582 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1583 | |
ccb469a1 SR |
1584 | struct ring_buffer_event * |
1585 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
1586 | struct ftrace_event_file *ftrace_file, | |
1587 | int type, unsigned long len, | |
1588 | unsigned long flags, int pc) | |
1589 | { | |
12883efb | 1590 | *current_rb = ftrace_file->tr->trace_buffer.buffer; |
ccb469a1 SR |
1591 | return trace_buffer_lock_reserve(*current_rb, |
1592 | type, len, flags, pc); | |
1593 | } | |
1594 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
1595 | ||
ef5580d0 | 1596 | struct ring_buffer_event * |
e77405ad SR |
1597 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1598 | int type, unsigned long len, | |
ef5580d0 SR |
1599 | unsigned long flags, int pc) |
1600 | { | |
12883efb | 1601 | *current_rb = global_trace.trace_buffer.buffer; |
e77405ad | 1602 | return trace_buffer_lock_reserve(*current_rb, |
ef5580d0 SR |
1603 | type, len, flags, pc); |
1604 | } | |
94487d6d | 1605 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1606 | |
e77405ad SR |
1607 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1608 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1609 | unsigned long flags, int pc) |
1610 | { | |
0d5c6e1c | 1611 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
07edf712 | 1612 | } |
94487d6d | 1613 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1614 | |
0d5c6e1c SR |
1615 | void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1616 | struct ring_buffer_event *event, | |
1617 | unsigned long flags, int pc, | |
1618 | struct pt_regs *regs) | |
1fd8df2c | 1619 | { |
7ffbd48d | 1620 | __buffer_unlock_commit(buffer, event); |
1fd8df2c MH |
1621 | |
1622 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1623 | ftrace_trace_userstack(buffer, flags, pc); | |
1624 | } | |
0d5c6e1c | 1625 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1626 | |
e77405ad SR |
1627 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1628 | struct ring_buffer_event *event) | |
77d9f465 | 1629 | { |
e77405ad | 1630 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1631 | } |
12acd473 | 1632 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1633 | |
e309b41d | 1634 | void |
7be42151 | 1635 | trace_function(struct trace_array *tr, |
38697053 SR |
1636 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1637 | int pc) | |
bc0c38d1 | 1638 | { |
e1112b4d | 1639 | struct ftrace_event_call *call = &event_function; |
12883efb | 1640 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 1641 | struct ring_buffer_event *event; |
777e208d | 1642 | struct ftrace_entry *entry; |
bc0c38d1 | 1643 | |
d769041f | 1644 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1645 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1646 | return; |
1647 | ||
e77405ad | 1648 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1649 | flags, pc); |
3928a8a2 SR |
1650 | if (!event) |
1651 | return; | |
1652 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1653 | entry->ip = ip; |
1654 | entry->parent_ip = parent_ip; | |
e1112b4d | 1655 | |
f306cc82 | 1656 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1657 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1658 | } |
1659 | ||
c0a0d0d3 | 1660 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1661 | |
1662 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1663 | struct ftrace_stack { | |
1664 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1665 | }; | |
1666 | ||
1667 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1668 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1669 | ||
e77405ad | 1670 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1671 | unsigned long flags, |
1fd8df2c | 1672 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1673 | { |
e1112b4d | 1674 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1675 | struct ring_buffer_event *event; |
777e208d | 1676 | struct stack_entry *entry; |
86387f7e | 1677 | struct stack_trace trace; |
4a9bd3f1 SR |
1678 | int use_stack; |
1679 | int size = FTRACE_STACK_ENTRIES; | |
1680 | ||
1681 | trace.nr_entries = 0; | |
1682 | trace.skip = skip; | |
1683 | ||
1684 | /* | |
1685 | * Since events can happen in NMIs there's no safe way to | |
1686 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1687 | * or NMI comes in, it will just have to use the default | |
1688 | * FTRACE_STACK_SIZE. | |
1689 | */ | |
1690 | preempt_disable_notrace(); | |
1691 | ||
82146529 | 1692 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
1693 | /* |
1694 | * We don't need any atomic variables, just a barrier. | |
1695 | * If an interrupt comes in, we don't care, because it would | |
1696 | * have exited and put the counter back to what we want. | |
1697 | * We just need a barrier to keep gcc from moving things | |
1698 | * around. | |
1699 | */ | |
1700 | barrier(); | |
1701 | if (use_stack == 1) { | |
1702 | trace.entries = &__get_cpu_var(ftrace_stack).calls[0]; | |
1703 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; | |
1704 | ||
1705 | if (regs) | |
1706 | save_stack_trace_regs(regs, &trace); | |
1707 | else | |
1708 | save_stack_trace(&trace); | |
1709 | ||
1710 | if (trace.nr_entries > size) | |
1711 | size = trace.nr_entries; | |
1712 | } else | |
1713 | /* From now on, use_stack is a boolean */ | |
1714 | use_stack = 0; | |
1715 | ||
1716 | size *= sizeof(unsigned long); | |
86387f7e | 1717 | |
e77405ad | 1718 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1719 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1720 | if (!event) |
4a9bd3f1 SR |
1721 | goto out; |
1722 | entry = ring_buffer_event_data(event); | |
86387f7e | 1723 | |
4a9bd3f1 SR |
1724 | memset(&entry->caller, 0, size); |
1725 | ||
1726 | if (use_stack) | |
1727 | memcpy(&entry->caller, trace.entries, | |
1728 | trace.nr_entries * sizeof(unsigned long)); | |
1729 | else { | |
1730 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1731 | trace.entries = entry->caller; | |
1732 | if (regs) | |
1733 | save_stack_trace_regs(regs, &trace); | |
1734 | else | |
1735 | save_stack_trace(&trace); | |
1736 | } | |
1737 | ||
1738 | entry->size = trace.nr_entries; | |
86387f7e | 1739 | |
f306cc82 | 1740 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1741 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1742 | |
1743 | out: | |
1744 | /* Again, don't let gcc optimize things here */ | |
1745 | barrier(); | |
82146529 | 1746 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
1747 | preempt_enable_notrace(); |
1748 | ||
f0a920d5 IM |
1749 | } |
1750 | ||
1fd8df2c MH |
1751 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1752 | int skip, int pc, struct pt_regs *regs) | |
1753 | { | |
1754 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1755 | return; | |
1756 | ||
1757 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1758 | } | |
1759 | ||
e77405ad SR |
1760 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1761 | int skip, int pc) | |
53614991 SR |
1762 | { |
1763 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1764 | return; | |
1765 | ||
1fd8df2c | 1766 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1767 | } |
1768 | ||
c0a0d0d3 FW |
1769 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1770 | int pc) | |
38697053 | 1771 | { |
12883efb | 1772 | __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); |
38697053 SR |
1773 | } |
1774 | ||
03889384 SR |
1775 | /** |
1776 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 1777 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 1778 | */ |
c142be8e | 1779 | void trace_dump_stack(int skip) |
03889384 SR |
1780 | { |
1781 | unsigned long flags; | |
1782 | ||
1783 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1784 | return; |
03889384 SR |
1785 | |
1786 | local_save_flags(flags); | |
1787 | ||
c142be8e SRRH |
1788 | /* |
1789 | * Skip 3 more, seems to get us at the caller of | |
1790 | * this function. | |
1791 | */ | |
1792 | skip += 3; | |
1793 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, | |
1794 | flags, skip, preempt_count(), NULL); | |
03889384 SR |
1795 | } |
1796 | ||
91e86e56 SR |
1797 | static DEFINE_PER_CPU(int, user_stack_count); |
1798 | ||
e77405ad SR |
1799 | void |
1800 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1801 | { |
e1112b4d | 1802 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1803 | struct ring_buffer_event *event; |
02b67518 TE |
1804 | struct userstack_entry *entry; |
1805 | struct stack_trace trace; | |
02b67518 TE |
1806 | |
1807 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1808 | return; | |
1809 | ||
b6345879 SR |
1810 | /* |
1811 | * NMIs can not handle page faults, even with fix ups. | |
1812 | * The save user stack can (and often does) fault. | |
1813 | */ | |
1814 | if (unlikely(in_nmi())) | |
1815 | return; | |
02b67518 | 1816 | |
91e86e56 SR |
1817 | /* |
1818 | * prevent recursion, since the user stack tracing may | |
1819 | * trigger other kernel events. | |
1820 | */ | |
1821 | preempt_disable(); | |
1822 | if (__this_cpu_read(user_stack_count)) | |
1823 | goto out; | |
1824 | ||
1825 | __this_cpu_inc(user_stack_count); | |
1826 | ||
e77405ad | 1827 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1828 | sizeof(*entry), flags, pc); |
02b67518 | 1829 | if (!event) |
1dbd1951 | 1830 | goto out_drop_count; |
02b67518 | 1831 | entry = ring_buffer_event_data(event); |
02b67518 | 1832 | |
48659d31 | 1833 | entry->tgid = current->tgid; |
02b67518 TE |
1834 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1835 | ||
1836 | trace.nr_entries = 0; | |
1837 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1838 | trace.skip = 0; | |
1839 | trace.entries = entry->caller; | |
1840 | ||
1841 | save_stack_trace_user(&trace); | |
f306cc82 | 1842 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1843 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1844 | |
1dbd1951 | 1845 | out_drop_count: |
91e86e56 | 1846 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1847 | out: |
1848 | preempt_enable(); | |
02b67518 TE |
1849 | } |
1850 | ||
4fd27358 HE |
1851 | #ifdef UNUSED |
1852 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1853 | { |
7be42151 | 1854 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1855 | } |
4fd27358 | 1856 | #endif /* UNUSED */ |
02b67518 | 1857 | |
c0a0d0d3 FW |
1858 | #endif /* CONFIG_STACKTRACE */ |
1859 | ||
07d777fe SR |
1860 | /* created for use with alloc_percpu */ |
1861 | struct trace_buffer_struct { | |
1862 | char buffer[TRACE_BUF_SIZE]; | |
1863 | }; | |
1864 | ||
1865 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1866 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1867 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1868 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1869 | ||
1870 | /* | |
1871 | * The buffer used is dependent on the context. There is a per cpu | |
1872 | * buffer for normal context, softirq contex, hard irq context and | |
1873 | * for NMI context. Thise allows for lockless recording. | |
1874 | * | |
1875 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1876 | */ | |
1877 | static char *get_trace_buf(void) | |
1878 | { | |
1879 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
1880 | |
1881 | /* | |
1882 | * If we have allocated per cpu buffers, then we do not | |
1883 | * need to do any locking. | |
1884 | */ | |
1885 | if (in_nmi()) | |
1886 | percpu_buffer = trace_percpu_nmi_buffer; | |
1887 | else if (in_irq()) | |
1888 | percpu_buffer = trace_percpu_irq_buffer; | |
1889 | else if (in_softirq()) | |
1890 | percpu_buffer = trace_percpu_sirq_buffer; | |
1891 | else | |
1892 | percpu_buffer = trace_percpu_buffer; | |
1893 | ||
1894 | if (!percpu_buffer) | |
1895 | return NULL; | |
1896 | ||
d8a0349c | 1897 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
1898 | } |
1899 | ||
1900 | static int alloc_percpu_trace_buffer(void) | |
1901 | { | |
1902 | struct trace_buffer_struct *buffers; | |
1903 | struct trace_buffer_struct *sirq_buffers; | |
1904 | struct trace_buffer_struct *irq_buffers; | |
1905 | struct trace_buffer_struct *nmi_buffers; | |
1906 | ||
1907 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1908 | if (!buffers) | |
1909 | goto err_warn; | |
1910 | ||
1911 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1912 | if (!sirq_buffers) | |
1913 | goto err_sirq; | |
1914 | ||
1915 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1916 | if (!irq_buffers) | |
1917 | goto err_irq; | |
1918 | ||
1919 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
1920 | if (!nmi_buffers) | |
1921 | goto err_nmi; | |
1922 | ||
1923 | trace_percpu_buffer = buffers; | |
1924 | trace_percpu_sirq_buffer = sirq_buffers; | |
1925 | trace_percpu_irq_buffer = irq_buffers; | |
1926 | trace_percpu_nmi_buffer = nmi_buffers; | |
1927 | ||
1928 | return 0; | |
1929 | ||
1930 | err_nmi: | |
1931 | free_percpu(irq_buffers); | |
1932 | err_irq: | |
1933 | free_percpu(sirq_buffers); | |
1934 | err_sirq: | |
1935 | free_percpu(buffers); | |
1936 | err_warn: | |
1937 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
1938 | return -ENOMEM; | |
1939 | } | |
1940 | ||
81698831 SR |
1941 | static int buffers_allocated; |
1942 | ||
07d777fe SR |
1943 | void trace_printk_init_buffers(void) |
1944 | { | |
07d777fe SR |
1945 | if (buffers_allocated) |
1946 | return; | |
1947 | ||
1948 | if (alloc_percpu_trace_buffer()) | |
1949 | return; | |
1950 | ||
1951 | pr_info("ftrace: Allocated trace_printk buffers\n"); | |
1952 | ||
b382ede6 SR |
1953 | /* Expand the buffers to set size */ |
1954 | tracing_update_buffers(); | |
1955 | ||
07d777fe | 1956 | buffers_allocated = 1; |
81698831 SR |
1957 | |
1958 | /* | |
1959 | * trace_printk_init_buffers() can be called by modules. | |
1960 | * If that happens, then we need to start cmdline recording | |
1961 | * directly here. If the global_trace.buffer is already | |
1962 | * allocated here, then this was called by module code. | |
1963 | */ | |
12883efb | 1964 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
1965 | tracing_start_cmdline_record(); |
1966 | } | |
1967 | ||
1968 | void trace_printk_start_comm(void) | |
1969 | { | |
1970 | /* Start tracing comms if trace printk is set */ | |
1971 | if (!buffers_allocated) | |
1972 | return; | |
1973 | tracing_start_cmdline_record(); | |
1974 | } | |
1975 | ||
1976 | static void trace_printk_start_stop_comm(int enabled) | |
1977 | { | |
1978 | if (!buffers_allocated) | |
1979 | return; | |
1980 | ||
1981 | if (enabled) | |
1982 | tracing_start_cmdline_record(); | |
1983 | else | |
1984 | tracing_stop_cmdline_record(); | |
07d777fe SR |
1985 | } |
1986 | ||
769b0441 | 1987 | /** |
48ead020 | 1988 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1989 | * |
1990 | */ | |
40ce74f1 | 1991 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1992 | { |
e1112b4d | 1993 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1994 | struct ring_buffer_event *event; |
e77405ad | 1995 | struct ring_buffer *buffer; |
769b0441 | 1996 | struct trace_array *tr = &global_trace; |
48ead020 | 1997 | struct bprint_entry *entry; |
769b0441 | 1998 | unsigned long flags; |
07d777fe SR |
1999 | char *tbuffer; |
2000 | int len = 0, size, pc; | |
769b0441 FW |
2001 | |
2002 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
2003 | return 0; | |
2004 | ||
2005 | /* Don't pollute graph traces with trace_vprintk internals */ | |
2006 | pause_graph_tracing(); | |
2007 | ||
2008 | pc = preempt_count(); | |
5168ae50 | 2009 | preempt_disable_notrace(); |
769b0441 | 2010 | |
07d777fe SR |
2011 | tbuffer = get_trace_buf(); |
2012 | if (!tbuffer) { | |
2013 | len = 0; | |
769b0441 | 2014 | goto out; |
07d777fe | 2015 | } |
769b0441 | 2016 | |
07d777fe | 2017 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 2018 | |
07d777fe SR |
2019 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
2020 | goto out; | |
769b0441 | 2021 | |
07d777fe | 2022 | local_save_flags(flags); |
769b0441 | 2023 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 2024 | buffer = tr->trace_buffer.buffer; |
e77405ad SR |
2025 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
2026 | flags, pc); | |
769b0441 | 2027 | if (!event) |
07d777fe | 2028 | goto out; |
769b0441 FW |
2029 | entry = ring_buffer_event_data(event); |
2030 | entry->ip = ip; | |
769b0441 FW |
2031 | entry->fmt = fmt; |
2032 | ||
07d777fe | 2033 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
f306cc82 | 2034 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2035 | __buffer_unlock_commit(buffer, event); |
d931369b SR |
2036 | ftrace_trace_stack(buffer, flags, 6, pc); |
2037 | } | |
769b0441 | 2038 | |
769b0441 | 2039 | out: |
5168ae50 | 2040 | preempt_enable_notrace(); |
769b0441 FW |
2041 | unpause_graph_tracing(); |
2042 | ||
2043 | return len; | |
2044 | } | |
48ead020 FW |
2045 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
2046 | ||
12883efb SRRH |
2047 | static int |
2048 | __trace_array_vprintk(struct ring_buffer *buffer, | |
2049 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 2050 | { |
e1112b4d | 2051 | struct ftrace_event_call *call = &event_print; |
48ead020 | 2052 | struct ring_buffer_event *event; |
07d777fe | 2053 | int len = 0, size, pc; |
48ead020 | 2054 | struct print_entry *entry; |
07d777fe SR |
2055 | unsigned long flags; |
2056 | char *tbuffer; | |
48ead020 FW |
2057 | |
2058 | if (tracing_disabled || tracing_selftest_running) | |
2059 | return 0; | |
2060 | ||
07d777fe SR |
2061 | /* Don't pollute graph traces with trace_vprintk internals */ |
2062 | pause_graph_tracing(); | |
2063 | ||
48ead020 FW |
2064 | pc = preempt_count(); |
2065 | preempt_disable_notrace(); | |
48ead020 | 2066 | |
07d777fe SR |
2067 | |
2068 | tbuffer = get_trace_buf(); | |
2069 | if (!tbuffer) { | |
2070 | len = 0; | |
48ead020 | 2071 | goto out; |
07d777fe | 2072 | } |
48ead020 | 2073 | |
07d777fe SR |
2074 | len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
2075 | if (len > TRACE_BUF_SIZE) | |
2076 | goto out; | |
48ead020 | 2077 | |
07d777fe | 2078 | local_save_flags(flags); |
48ead020 | 2079 | size = sizeof(*entry) + len + 1; |
e77405ad | 2080 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
07d777fe | 2081 | flags, pc); |
48ead020 | 2082 | if (!event) |
07d777fe | 2083 | goto out; |
48ead020 | 2084 | entry = ring_buffer_event_data(event); |
c13d2f7c | 2085 | entry->ip = ip; |
48ead020 | 2086 | |
07d777fe | 2087 | memcpy(&entry->buf, tbuffer, len); |
c13d2f7c | 2088 | entry->buf[len] = '\0'; |
f306cc82 | 2089 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2090 | __buffer_unlock_commit(buffer, event); |
07d777fe | 2091 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 2092 | } |
48ead020 FW |
2093 | out: |
2094 | preempt_enable_notrace(); | |
07d777fe | 2095 | unpause_graph_tracing(); |
48ead020 FW |
2096 | |
2097 | return len; | |
2098 | } | |
659372d3 | 2099 | |
12883efb SRRH |
2100 | int trace_array_vprintk(struct trace_array *tr, |
2101 | unsigned long ip, const char *fmt, va_list args) | |
2102 | { | |
2103 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
2104 | } | |
2105 | ||
2106 | int trace_array_printk(struct trace_array *tr, | |
2107 | unsigned long ip, const char *fmt, ...) | |
2108 | { | |
2109 | int ret; | |
2110 | va_list ap; | |
2111 | ||
2112 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2113 | return 0; | |
2114 | ||
2115 | va_start(ap, fmt); | |
2116 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
2117 | va_end(ap); | |
2118 | return ret; | |
2119 | } | |
2120 | ||
2121 | int trace_array_printk_buf(struct ring_buffer *buffer, | |
2122 | unsigned long ip, const char *fmt, ...) | |
2123 | { | |
2124 | int ret; | |
2125 | va_list ap; | |
2126 | ||
2127 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2128 | return 0; | |
2129 | ||
2130 | va_start(ap, fmt); | |
2131 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
2132 | va_end(ap); | |
2133 | return ret; | |
2134 | } | |
2135 | ||
659372d3 SR |
2136 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
2137 | { | |
a813a159 | 2138 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 2139 | } |
769b0441 FW |
2140 | EXPORT_SYMBOL_GPL(trace_vprintk); |
2141 | ||
e2ac8ef5 | 2142 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 2143 | { |
6d158a81 SR |
2144 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
2145 | ||
5a90f577 | 2146 | iter->idx++; |
6d158a81 SR |
2147 | if (buf_iter) |
2148 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
2149 | } |
2150 | ||
e309b41d | 2151 | static struct trace_entry * |
bc21b478 SR |
2152 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
2153 | unsigned long *lost_events) | |
dd0e545f | 2154 | { |
3928a8a2 | 2155 | struct ring_buffer_event *event; |
6d158a81 | 2156 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 2157 | |
d769041f SR |
2158 | if (buf_iter) |
2159 | event = ring_buffer_iter_peek(buf_iter, ts); | |
2160 | else | |
12883efb | 2161 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 2162 | lost_events); |
d769041f | 2163 | |
4a9bd3f1 SR |
2164 | if (event) { |
2165 | iter->ent_size = ring_buffer_event_length(event); | |
2166 | return ring_buffer_event_data(event); | |
2167 | } | |
2168 | iter->ent_size = 0; | |
2169 | return NULL; | |
dd0e545f | 2170 | } |
d769041f | 2171 | |
dd0e545f | 2172 | static struct trace_entry * |
bc21b478 SR |
2173 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
2174 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 2175 | { |
12883efb | 2176 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 2177 | struct trace_entry *ent, *next = NULL; |
aa27497c | 2178 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 2179 | int cpu_file = iter->cpu_file; |
3928a8a2 | 2180 | u64 next_ts = 0, ts; |
bc0c38d1 | 2181 | int next_cpu = -1; |
12b5da34 | 2182 | int next_size = 0; |
bc0c38d1 SR |
2183 | int cpu; |
2184 | ||
b04cc6b1 FW |
2185 | /* |
2186 | * If we are in a per_cpu trace file, don't bother by iterating over | |
2187 | * all cpu and peek directly. | |
2188 | */ | |
ae3b5093 | 2189 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
2190 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
2191 | return NULL; | |
bc21b478 | 2192 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
2193 | if (ent_cpu) |
2194 | *ent_cpu = cpu_file; | |
2195 | ||
2196 | return ent; | |
2197 | } | |
2198 | ||
ab46428c | 2199 | for_each_tracing_cpu(cpu) { |
dd0e545f | 2200 | |
3928a8a2 SR |
2201 | if (ring_buffer_empty_cpu(buffer, cpu)) |
2202 | continue; | |
dd0e545f | 2203 | |
bc21b478 | 2204 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 2205 | |
cdd31cd2 IM |
2206 | /* |
2207 | * Pick the entry with the smallest timestamp: | |
2208 | */ | |
3928a8a2 | 2209 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
2210 | next = ent; |
2211 | next_cpu = cpu; | |
3928a8a2 | 2212 | next_ts = ts; |
bc21b478 | 2213 | next_lost = lost_events; |
12b5da34 | 2214 | next_size = iter->ent_size; |
bc0c38d1 SR |
2215 | } |
2216 | } | |
2217 | ||
12b5da34 SR |
2218 | iter->ent_size = next_size; |
2219 | ||
bc0c38d1 SR |
2220 | if (ent_cpu) |
2221 | *ent_cpu = next_cpu; | |
2222 | ||
3928a8a2 SR |
2223 | if (ent_ts) |
2224 | *ent_ts = next_ts; | |
2225 | ||
bc21b478 SR |
2226 | if (missing_events) |
2227 | *missing_events = next_lost; | |
2228 | ||
bc0c38d1 SR |
2229 | return next; |
2230 | } | |
2231 | ||
dd0e545f | 2232 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
2233 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
2234 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 2235 | { |
bc21b478 | 2236 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
2237 | } |
2238 | ||
2239 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 2240 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 2241 | { |
bc21b478 SR |
2242 | iter->ent = __find_next_entry(iter, &iter->cpu, |
2243 | &iter->lost_events, &iter->ts); | |
dd0e545f | 2244 | |
3928a8a2 | 2245 | if (iter->ent) |
e2ac8ef5 | 2246 | trace_iterator_increment(iter); |
dd0e545f | 2247 | |
3928a8a2 | 2248 | return iter->ent ? iter : NULL; |
b3806b43 | 2249 | } |
bc0c38d1 | 2250 | |
e309b41d | 2251 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 2252 | { |
12883efb | 2253 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 2254 | &iter->lost_events); |
bc0c38d1 SR |
2255 | } |
2256 | ||
e309b41d | 2257 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
2258 | { |
2259 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 2260 | int i = (int)*pos; |
4e3c3333 | 2261 | void *ent; |
bc0c38d1 | 2262 | |
a63ce5b3 SR |
2263 | WARN_ON_ONCE(iter->leftover); |
2264 | ||
bc0c38d1 SR |
2265 | (*pos)++; |
2266 | ||
2267 | /* can't go backwards */ | |
2268 | if (iter->idx > i) | |
2269 | return NULL; | |
2270 | ||
2271 | if (iter->idx < 0) | |
955b61e5 | 2272 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2273 | else |
2274 | ent = iter; | |
2275 | ||
2276 | while (ent && iter->idx < i) | |
955b61e5 | 2277 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2278 | |
2279 | iter->pos = *pos; | |
2280 | ||
bc0c38d1 SR |
2281 | return ent; |
2282 | } | |
2283 | ||
955b61e5 | 2284 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 2285 | { |
2f26ebd5 SR |
2286 | struct ring_buffer_event *event; |
2287 | struct ring_buffer_iter *buf_iter; | |
2288 | unsigned long entries = 0; | |
2289 | u64 ts; | |
2290 | ||
12883efb | 2291 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 2292 | |
6d158a81 SR |
2293 | buf_iter = trace_buffer_iter(iter, cpu); |
2294 | if (!buf_iter) | |
2f26ebd5 SR |
2295 | return; |
2296 | ||
2f26ebd5 SR |
2297 | ring_buffer_iter_reset(buf_iter); |
2298 | ||
2299 | /* | |
2300 | * We could have the case with the max latency tracers | |
2301 | * that a reset never took place on a cpu. This is evident | |
2302 | * by the timestamp being before the start of the buffer. | |
2303 | */ | |
2304 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 2305 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
2306 | break; |
2307 | entries++; | |
2308 | ring_buffer_read(buf_iter, NULL); | |
2309 | } | |
2310 | ||
12883efb | 2311 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2312 | } |
2313 | ||
d7350c3f | 2314 | /* |
d7350c3f FW |
2315 | * The current tracer is copied to avoid a global locking |
2316 | * all around. | |
2317 | */ | |
bc0c38d1 SR |
2318 | static void *s_start(struct seq_file *m, loff_t *pos) |
2319 | { | |
2320 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2321 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2322 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2323 | void *p = NULL; |
2324 | loff_t l = 0; | |
3928a8a2 | 2325 | int cpu; |
bc0c38d1 | 2326 | |
2fd196ec HT |
2327 | /* |
2328 | * copy the tracer to avoid using a global lock all around. | |
2329 | * iter->trace is a copy of current_trace, the pointer to the | |
2330 | * name may be used instead of a strcmp(), as iter->trace->name | |
2331 | * will point to the same string as current_trace->name. | |
2332 | */ | |
bc0c38d1 | 2333 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2334 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2335 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2336 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2337 | |
12883efb | 2338 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2339 | if (iter->snapshot && iter->trace->use_max_tr) |
2340 | return ERR_PTR(-EBUSY); | |
12883efb | 2341 | #endif |
debdd57f HT |
2342 | |
2343 | if (!iter->snapshot) | |
2344 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2345 | |
bc0c38d1 SR |
2346 | if (*pos != iter->pos) { |
2347 | iter->ent = NULL; | |
2348 | iter->cpu = 0; | |
2349 | iter->idx = -1; | |
2350 | ||
ae3b5093 | 2351 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2352 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2353 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2354 | } else |
2f26ebd5 | 2355 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2356 | |
ac91d854 | 2357 | iter->leftover = 0; |
bc0c38d1 SR |
2358 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2359 | ; | |
2360 | ||
2361 | } else { | |
a63ce5b3 SR |
2362 | /* |
2363 | * If we overflowed the seq_file before, then we want | |
2364 | * to just reuse the trace_seq buffer again. | |
2365 | */ | |
2366 | if (iter->leftover) | |
2367 | p = iter; | |
2368 | else { | |
2369 | l = *pos - 1; | |
2370 | p = s_next(m, p, &l); | |
2371 | } | |
bc0c38d1 SR |
2372 | } |
2373 | ||
4f535968 | 2374 | trace_event_read_lock(); |
7e53bd42 | 2375 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2376 | return p; |
2377 | } | |
2378 | ||
2379 | static void s_stop(struct seq_file *m, void *p) | |
2380 | { | |
7e53bd42 LJ |
2381 | struct trace_iterator *iter = m->private; |
2382 | ||
12883efb | 2383 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2384 | if (iter->snapshot && iter->trace->use_max_tr) |
2385 | return; | |
12883efb | 2386 | #endif |
debdd57f HT |
2387 | |
2388 | if (!iter->snapshot) | |
2389 | atomic_dec(&trace_record_cmdline_disabled); | |
12883efb | 2390 | |
7e53bd42 | 2391 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2392 | trace_event_read_unlock(); |
bc0c38d1 SR |
2393 | } |
2394 | ||
39eaf7ef | 2395 | static void |
12883efb SRRH |
2396 | get_total_entries(struct trace_buffer *buf, |
2397 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
2398 | { |
2399 | unsigned long count; | |
2400 | int cpu; | |
2401 | ||
2402 | *total = 0; | |
2403 | *entries = 0; | |
2404 | ||
2405 | for_each_tracing_cpu(cpu) { | |
12883efb | 2406 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2407 | /* |
2408 | * If this buffer has skipped entries, then we hold all | |
2409 | * entries for the trace and we need to ignore the | |
2410 | * ones before the time stamp. | |
2411 | */ | |
12883efb SRRH |
2412 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
2413 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2414 | /* total is the same as the entries */ |
2415 | *total += count; | |
2416 | } else | |
2417 | *total += count + | |
12883efb | 2418 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2419 | *entries += count; |
2420 | } | |
2421 | } | |
2422 | ||
e309b41d | 2423 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2424 | { |
a6168353 ME |
2425 | seq_puts(m, "# _------=> CPU# \n"); |
2426 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
2427 | seq_puts(m, "# | / _----=> need-resched \n"); | |
2428 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
2429 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
2430 | seq_puts(m, "# |||| / delay \n"); |
2431 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
2432 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2433 | } |
2434 | ||
12883efb | 2435 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 2436 | { |
39eaf7ef SR |
2437 | unsigned long total; |
2438 | unsigned long entries; | |
2439 | ||
12883efb | 2440 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
2441 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
2442 | entries, total, num_online_cpus()); | |
2443 | seq_puts(m, "#\n"); | |
2444 | } | |
2445 | ||
12883efb | 2446 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) |
39eaf7ef | 2447 | { |
12883efb | 2448 | print_event_info(buf, m); |
77271ce4 | 2449 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
a6168353 | 2450 | seq_puts(m, "# | | | | |\n"); |
bc0c38d1 SR |
2451 | } |
2452 | ||
12883efb | 2453 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) |
77271ce4 | 2454 | { |
12883efb | 2455 | print_event_info(buf, m); |
77271ce4 SR |
2456 | seq_puts(m, "# _-----=> irqs-off\n"); |
2457 | seq_puts(m, "# / _----=> need-resched\n"); | |
2458 | seq_puts(m, "# | / _---=> hardirq/softirq\n"); | |
2459 | seq_puts(m, "# || / _--=> preempt-depth\n"); | |
2460 | seq_puts(m, "# ||| / delay\n"); | |
2461 | seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); | |
2462 | seq_puts(m, "# | | | |||| | |\n"); | |
2463 | } | |
bc0c38d1 | 2464 | |
62b915f1 | 2465 | void |
bc0c38d1 SR |
2466 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2467 | { | |
2468 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
12883efb SRRH |
2469 | struct trace_buffer *buf = iter->trace_buffer; |
2470 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 2471 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2472 | unsigned long entries; |
2473 | unsigned long total; | |
bc0c38d1 SR |
2474 | const char *name = "preemption"; |
2475 | ||
d840f718 | 2476 | name = type->name; |
bc0c38d1 | 2477 | |
12883efb | 2478 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 2479 | |
888b55dc | 2480 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2481 | name, UTS_RELEASE); |
888b55dc | 2482 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2483 | "---------------------------------\n"); |
888b55dc | 2484 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2485 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2486 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2487 | entries, |
4c11d7ae | 2488 | total, |
12883efb | 2489 | buf->cpu, |
bc0c38d1 SR |
2490 | #if defined(CONFIG_PREEMPT_NONE) |
2491 | "server", | |
2492 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2493 | "desktop", | |
b5c21b45 | 2494 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2495 | "preempt", |
2496 | #else | |
2497 | "unknown", | |
2498 | #endif | |
2499 | /* These are reserved for later use */ | |
2500 | 0, 0, 0, 0); | |
2501 | #ifdef CONFIG_SMP | |
2502 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2503 | #else | |
2504 | seq_puts(m, ")\n"); | |
2505 | #endif | |
888b55dc KM |
2506 | seq_puts(m, "# -----------------\n"); |
2507 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2508 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2509 | data->comm, data->pid, |
2510 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2511 | data->policy, data->rt_priority); |
888b55dc | 2512 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2513 | |
2514 | if (data->critical_start) { | |
888b55dc | 2515 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2516 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2517 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2518 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2519 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2520 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2521 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2522 | } |
2523 | ||
888b55dc | 2524 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2525 | } |
2526 | ||
a309720c SR |
2527 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2528 | { | |
2529 | struct trace_seq *s = &iter->seq; | |
2530 | ||
12ef7d44 SR |
2531 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2532 | return; | |
2533 | ||
2534 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2535 | return; | |
2536 | ||
4462344e | 2537 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2538 | return; |
2539 | ||
12883efb | 2540 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
2541 | return; |
2542 | ||
4462344e | 2543 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2544 | |
2545 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2546 | if (iter->idx > 1) | |
2547 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2548 | iter->cpu); | |
a309720c SR |
2549 | } |
2550 | ||
2c4f035f | 2551 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2552 | { |
214023c3 | 2553 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2554 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2555 | struct trace_entry *entry; |
f633cef0 | 2556 | struct trace_event *event; |
bc0c38d1 | 2557 | |
4e3c3333 | 2558 | entry = iter->ent; |
dd0e545f | 2559 | |
a309720c SR |
2560 | test_cpu_buff_start(iter); |
2561 | ||
c4a8e8be | 2562 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2563 | |
c4a8e8be | 2564 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
2565 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2566 | if (!trace_print_lat_context(iter)) | |
2567 | goto partial; | |
2568 | } else { | |
2569 | if (!trace_print_context(iter)) | |
2570 | goto partial; | |
2571 | } | |
c4a8e8be | 2572 | } |
bc0c38d1 | 2573 | |
268ccda0 | 2574 | if (event) |
a9a57763 | 2575 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
2576 | |
2577 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
2578 | goto partial; | |
02b67518 | 2579 | |
2c4f035f | 2580 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2581 | partial: |
2582 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
2583 | } |
2584 | ||
2c4f035f | 2585 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2586 | { |
2587 | struct trace_seq *s = &iter->seq; | |
2588 | struct trace_entry *entry; | |
f633cef0 | 2589 | struct trace_event *event; |
f9896bf3 IM |
2590 | |
2591 | entry = iter->ent; | |
dd0e545f | 2592 | |
c4a8e8be | 2593 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
2594 | if (!trace_seq_printf(s, "%d %d %llu ", |
2595 | entry->pid, iter->cpu, iter->ts)) | |
2596 | goto partial; | |
c4a8e8be | 2597 | } |
f9896bf3 | 2598 | |
f633cef0 | 2599 | event = ftrace_find_event(entry->type); |
268ccda0 | 2600 | if (event) |
a9a57763 | 2601 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
2602 | |
2603 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
2604 | goto partial; | |
777e208d | 2605 | |
2c4f035f | 2606 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2607 | partial: |
2608 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
2609 | } |
2610 | ||
2c4f035f | 2611 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2612 | { |
2613 | struct trace_seq *s = &iter->seq; | |
2614 | unsigned char newline = '\n'; | |
2615 | struct trace_entry *entry; | |
f633cef0 | 2616 | struct trace_event *event; |
5e3ca0ec IM |
2617 | |
2618 | entry = iter->ent; | |
dd0e545f | 2619 | |
c4a8e8be FW |
2620 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2621 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
2622 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
2623 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
2624 | } | |
5e3ca0ec | 2625 | |
f633cef0 | 2626 | event = ftrace_find_event(entry->type); |
268ccda0 | 2627 | if (event) { |
a9a57763 | 2628 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2629 | if (ret != TRACE_TYPE_HANDLED) |
2630 | return ret; | |
2631 | } | |
7104f300 | 2632 | |
5e3ca0ec IM |
2633 | SEQ_PUT_FIELD_RET(s, newline); |
2634 | ||
2c4f035f | 2635 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
2636 | } |
2637 | ||
2c4f035f | 2638 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2639 | { |
2640 | struct trace_seq *s = &iter->seq; | |
2641 | struct trace_entry *entry; | |
f633cef0 | 2642 | struct trace_event *event; |
cb0f12aa IM |
2643 | |
2644 | entry = iter->ent; | |
dd0e545f | 2645 | |
c4a8e8be FW |
2646 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2647 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 2648 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2649 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2650 | } | |
cb0f12aa | 2651 | |
f633cef0 | 2652 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2653 | return event ? event->funcs->binary(iter, 0, event) : |
2654 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2655 | } |
2656 | ||
62b915f1 | 2657 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2658 | { |
6d158a81 | 2659 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2660 | int cpu; |
2661 | ||
9aba60fe | 2662 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 2663 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 2664 | cpu = iter->cpu_file; |
6d158a81 SR |
2665 | buf_iter = trace_buffer_iter(iter, cpu); |
2666 | if (buf_iter) { | |
2667 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2668 | return 0; |
2669 | } else { | |
12883efb | 2670 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
2671 | return 0; |
2672 | } | |
2673 | return 1; | |
2674 | } | |
2675 | ||
ab46428c | 2676 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2677 | buf_iter = trace_buffer_iter(iter, cpu); |
2678 | if (buf_iter) { | |
2679 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2680 | return 0; |
2681 | } else { | |
12883efb | 2682 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
2683 | return 0; |
2684 | } | |
bc0c38d1 | 2685 | } |
d769041f | 2686 | |
797d3712 | 2687 | return 1; |
bc0c38d1 SR |
2688 | } |
2689 | ||
4f535968 | 2690 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2691 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2692 | { |
2c4f035f FW |
2693 | enum print_line_t ret; |
2694 | ||
ee5e51f5 JO |
2695 | if (iter->lost_events && |
2696 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2697 | iter->cpu, iter->lost_events)) | |
2698 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2699 | |
2c4f035f FW |
2700 | if (iter->trace && iter->trace->print_line) { |
2701 | ret = iter->trace->print_line(iter); | |
2702 | if (ret != TRACE_TYPE_UNHANDLED) | |
2703 | return ret; | |
2704 | } | |
72829bc3 | 2705 | |
09ae7234 SRRH |
2706 | if (iter->ent->type == TRACE_BPUTS && |
2707 | trace_flags & TRACE_ITER_PRINTK && | |
2708 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
2709 | return trace_print_bputs_msg_only(iter); | |
2710 | ||
48ead020 FW |
2711 | if (iter->ent->type == TRACE_BPRINT && |
2712 | trace_flags & TRACE_ITER_PRINTK && | |
2713 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2714 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2715 | |
66896a85 FW |
2716 | if (iter->ent->type == TRACE_PRINT && |
2717 | trace_flags & TRACE_ITER_PRINTK && | |
2718 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2719 | return trace_print_printk_msg_only(iter); |
66896a85 | 2720 | |
cb0f12aa IM |
2721 | if (trace_flags & TRACE_ITER_BIN) |
2722 | return print_bin_fmt(iter); | |
2723 | ||
5e3ca0ec IM |
2724 | if (trace_flags & TRACE_ITER_HEX) |
2725 | return print_hex_fmt(iter); | |
2726 | ||
f9896bf3 IM |
2727 | if (trace_flags & TRACE_ITER_RAW) |
2728 | return print_raw_fmt(iter); | |
2729 | ||
f9896bf3 IM |
2730 | return print_trace_fmt(iter); |
2731 | } | |
2732 | ||
7e9a49ef JO |
2733 | void trace_latency_header(struct seq_file *m) |
2734 | { | |
2735 | struct trace_iterator *iter = m->private; | |
2736 | ||
2737 | /* print nothing if the buffers are empty */ | |
2738 | if (trace_empty(iter)) | |
2739 | return; | |
2740 | ||
2741 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2742 | print_trace_header(m, iter); | |
2743 | ||
2744 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2745 | print_lat_help_header(m); | |
2746 | } | |
2747 | ||
62b915f1 JO |
2748 | void trace_default_header(struct seq_file *m) |
2749 | { | |
2750 | struct trace_iterator *iter = m->private; | |
2751 | ||
f56e7f8e JO |
2752 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2753 | return; | |
2754 | ||
62b915f1 JO |
2755 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2756 | /* print nothing if the buffers are empty */ | |
2757 | if (trace_empty(iter)) | |
2758 | return; | |
2759 | print_trace_header(m, iter); | |
2760 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2761 | print_lat_help_header(m); | |
2762 | } else { | |
77271ce4 SR |
2763 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2764 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
12883efb | 2765 | print_func_help_header_irq(iter->trace_buffer, m); |
77271ce4 | 2766 | else |
12883efb | 2767 | print_func_help_header(iter->trace_buffer, m); |
77271ce4 | 2768 | } |
62b915f1 JO |
2769 | } |
2770 | } | |
2771 | ||
e0a413f6 SR |
2772 | static void test_ftrace_alive(struct seq_file *m) |
2773 | { | |
2774 | if (!ftrace_is_dead()) | |
2775 | return; | |
2776 | seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
2777 | seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n"); | |
2778 | } | |
2779 | ||
d8741e2e | 2780 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 2781 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 2782 | { |
d8741e2e SRRH |
2783 | seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n"); |
2784 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2785 | seq_printf(m, "# Takes a snapshot of the main buffer.\n"); | |
b9be6d02 | 2786 | seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n"); |
d8741e2e SRRH |
2787 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); |
2788 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2789 | } | |
f1affcaa SRRH |
2790 | |
2791 | static void show_snapshot_percpu_help(struct seq_file *m) | |
2792 | { | |
2793 | seq_printf(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); | |
2794 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP | |
2795 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2796 | seq_printf(m, "# Takes a snapshot of the main buffer for this cpu.\n"); | |
2797 | #else | |
2798 | seq_printf(m, "# echo 1 > snapshot : Not supported with this kernel.\n"); | |
2799 | seq_printf(m, "# Must use main snapshot file to allocate.\n"); | |
2800 | #endif | |
2801 | seq_printf(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n"); | |
2802 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); | |
2803 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2804 | } | |
2805 | ||
d8741e2e SRRH |
2806 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
2807 | { | |
45ad21ca | 2808 | if (iter->tr->allocated_snapshot) |
d8741e2e SRRH |
2809 | seq_printf(m, "#\n# * Snapshot is allocated *\n#\n"); |
2810 | else | |
2811 | seq_printf(m, "#\n# * Snapshot is freed *\n#\n"); | |
2812 | ||
2813 | seq_printf(m, "# Snapshot commands:\n"); | |
f1affcaa SRRH |
2814 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
2815 | show_snapshot_main_help(m); | |
2816 | else | |
2817 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
2818 | } |
2819 | #else | |
2820 | /* Should never be called */ | |
2821 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
2822 | #endif | |
2823 | ||
bc0c38d1 SR |
2824 | static int s_show(struct seq_file *m, void *v) |
2825 | { | |
2826 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2827 | int ret; |
bc0c38d1 SR |
2828 | |
2829 | if (iter->ent == NULL) { | |
2830 | if (iter->tr) { | |
2831 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2832 | seq_puts(m, "#\n"); | |
e0a413f6 | 2833 | test_ftrace_alive(m); |
bc0c38d1 | 2834 | } |
d8741e2e SRRH |
2835 | if (iter->snapshot && trace_empty(iter)) |
2836 | print_snapshot_help(m, iter); | |
2837 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 2838 | iter->trace->print_header(m); |
62b915f1 JO |
2839 | else |
2840 | trace_default_header(m); | |
2841 | ||
a63ce5b3 SR |
2842 | } else if (iter->leftover) { |
2843 | /* | |
2844 | * If we filled the seq_file buffer earlier, we | |
2845 | * want to just show it now. | |
2846 | */ | |
2847 | ret = trace_print_seq(m, &iter->seq); | |
2848 | ||
2849 | /* ret should this time be zero, but you never know */ | |
2850 | iter->leftover = ret; | |
2851 | ||
bc0c38d1 | 2852 | } else { |
f9896bf3 | 2853 | print_trace_line(iter); |
a63ce5b3 SR |
2854 | ret = trace_print_seq(m, &iter->seq); |
2855 | /* | |
2856 | * If we overflow the seq_file buffer, then it will | |
2857 | * ask us for this data again at start up. | |
2858 | * Use that instead. | |
2859 | * ret is 0 if seq_file write succeeded. | |
2860 | * -1 otherwise. | |
2861 | */ | |
2862 | iter->leftover = ret; | |
bc0c38d1 SR |
2863 | } |
2864 | ||
2865 | return 0; | |
2866 | } | |
2867 | ||
649e9c70 ON |
2868 | /* |
2869 | * Should be used after trace_array_get(), trace_types_lock | |
2870 | * ensures that i_cdev was already initialized. | |
2871 | */ | |
2872 | static inline int tracing_get_cpu(struct inode *inode) | |
2873 | { | |
2874 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
2875 | return (long)inode->i_cdev - 1; | |
2876 | return RING_BUFFER_ALL_CPUS; | |
2877 | } | |
2878 | ||
88e9d34c | 2879 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2880 | .start = s_start, |
2881 | .next = s_next, | |
2882 | .stop = s_stop, | |
2883 | .show = s_show, | |
bc0c38d1 SR |
2884 | }; |
2885 | ||
e309b41d | 2886 | static struct trace_iterator * |
6484c71c | 2887 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 2888 | { |
6484c71c | 2889 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 2890 | struct trace_iterator *iter; |
50e18b94 | 2891 | int cpu; |
bc0c38d1 | 2892 | |
85a2f9b4 SR |
2893 | if (tracing_disabled) |
2894 | return ERR_PTR(-ENODEV); | |
60a11774 | 2895 | |
50e18b94 | 2896 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2897 | if (!iter) |
2898 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2899 | |
6d158a81 SR |
2900 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
2901 | GFP_KERNEL); | |
93574fcc DC |
2902 | if (!iter->buffer_iter) |
2903 | goto release; | |
2904 | ||
d7350c3f FW |
2905 | /* |
2906 | * We make a copy of the current tracer to avoid concurrent | |
2907 | * changes on it while we are reading. | |
2908 | */ | |
bc0c38d1 | 2909 | mutex_lock(&trace_types_lock); |
d7350c3f | 2910 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2911 | if (!iter->trace) |
d7350c3f | 2912 | goto fail; |
85a2f9b4 | 2913 | |
2b6080f2 | 2914 | *iter->trace = *tr->current_trace; |
d7350c3f | 2915 | |
79f55997 | 2916 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2917 | goto fail; |
2918 | ||
12883efb SRRH |
2919 | iter->tr = tr; |
2920 | ||
2921 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
2922 | /* Currently only the top directory has a snapshot */ |
2923 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 2924 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 2925 | else |
12883efb SRRH |
2926 | #endif |
2927 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 2928 | iter->snapshot = snapshot; |
bc0c38d1 | 2929 | iter->pos = -1; |
6484c71c | 2930 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 2931 | mutex_init(&iter->mutex); |
bc0c38d1 | 2932 | |
8bba1bf5 MM |
2933 | /* Notify the tracer early; before we stop tracing. */ |
2934 | if (iter->trace && iter->trace->open) | |
a93751ca | 2935 | iter->trace->open(iter); |
8bba1bf5 | 2936 | |
12ef7d44 | 2937 | /* Annotate start of buffers if we had overruns */ |
12883efb | 2938 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
2939 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
2940 | ||
8be0709f | 2941 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 2942 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
2943 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
2944 | ||
debdd57f HT |
2945 | /* stop the trace while dumping if we are not opening "snapshot" */ |
2946 | if (!iter->snapshot) | |
2b6080f2 | 2947 | tracing_stop_tr(tr); |
2f26ebd5 | 2948 | |
ae3b5093 | 2949 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2950 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 2951 | iter->buffer_iter[cpu] = |
12883efb | 2952 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
2953 | } |
2954 | ring_buffer_read_prepare_sync(); | |
2955 | for_each_tracing_cpu(cpu) { | |
2956 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2957 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2958 | } |
2959 | } else { | |
2960 | cpu = iter->cpu_file; | |
3928a8a2 | 2961 | iter->buffer_iter[cpu] = |
12883efb | 2962 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
2963 | ring_buffer_read_prepare_sync(); |
2964 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2965 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2966 | } |
2967 | ||
bc0c38d1 SR |
2968 | mutex_unlock(&trace_types_lock); |
2969 | ||
bc0c38d1 | 2970 | return iter; |
3928a8a2 | 2971 | |
d7350c3f | 2972 | fail: |
3928a8a2 | 2973 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2974 | kfree(iter->trace); |
6d158a81 | 2975 | kfree(iter->buffer_iter); |
93574fcc | 2976 | release: |
50e18b94 JO |
2977 | seq_release_private(inode, file); |
2978 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
2979 | } |
2980 | ||
2981 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2982 | { | |
60a11774 SR |
2983 | if (tracing_disabled) |
2984 | return -ENODEV; | |
2985 | ||
bc0c38d1 SR |
2986 | filp->private_data = inode->i_private; |
2987 | return 0; | |
2988 | } | |
2989 | ||
7b85af63 SRRH |
2990 | /* |
2991 | * Open and update trace_array ref count. | |
2992 | * Must have the current trace_array passed to it. | |
2993 | */ | |
dcc30223 | 2994 | static int tracing_open_generic_tr(struct inode *inode, struct file *filp) |
7b85af63 SRRH |
2995 | { |
2996 | struct trace_array *tr = inode->i_private; | |
2997 | ||
2998 | if (tracing_disabled) | |
2999 | return -ENODEV; | |
3000 | ||
3001 | if (trace_array_get(tr) < 0) | |
3002 | return -ENODEV; | |
3003 | ||
3004 | filp->private_data = inode->i_private; | |
3005 | ||
3006 | return 0; | |
7b85af63 SRRH |
3007 | } |
3008 | ||
4fd27358 | 3009 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 3010 | { |
6484c71c | 3011 | struct trace_array *tr = inode->i_private; |
907f2784 | 3012 | struct seq_file *m = file->private_data; |
4acd4d00 | 3013 | struct trace_iterator *iter; |
3928a8a2 | 3014 | int cpu; |
bc0c38d1 | 3015 | |
ff451961 | 3016 | if (!(file->f_mode & FMODE_READ)) { |
6484c71c | 3017 | trace_array_put(tr); |
4acd4d00 | 3018 | return 0; |
ff451961 | 3019 | } |
4acd4d00 | 3020 | |
6484c71c | 3021 | /* Writes do not use seq_file */ |
4acd4d00 | 3022 | iter = m->private; |
bc0c38d1 | 3023 | mutex_lock(&trace_types_lock); |
a695cb58 | 3024 | |
3928a8a2 SR |
3025 | for_each_tracing_cpu(cpu) { |
3026 | if (iter->buffer_iter[cpu]) | |
3027 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
3028 | } | |
3029 | ||
bc0c38d1 SR |
3030 | if (iter->trace && iter->trace->close) |
3031 | iter->trace->close(iter); | |
3032 | ||
debdd57f HT |
3033 | if (!iter->snapshot) |
3034 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 3035 | tracing_start_tr(tr); |
f77d09a3 AL |
3036 | |
3037 | __trace_array_put(tr); | |
3038 | ||
bc0c38d1 SR |
3039 | mutex_unlock(&trace_types_lock); |
3040 | ||
d7350c3f | 3041 | mutex_destroy(&iter->mutex); |
b0dfa978 | 3042 | free_cpumask_var(iter->started); |
d7350c3f | 3043 | kfree(iter->trace); |
6d158a81 | 3044 | kfree(iter->buffer_iter); |
50e18b94 | 3045 | seq_release_private(inode, file); |
ff451961 | 3046 | |
bc0c38d1 SR |
3047 | return 0; |
3048 | } | |
3049 | ||
7b85af63 SRRH |
3050 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
3051 | { | |
3052 | struct trace_array *tr = inode->i_private; | |
3053 | ||
3054 | trace_array_put(tr); | |
bc0c38d1 SR |
3055 | return 0; |
3056 | } | |
3057 | ||
7b85af63 SRRH |
3058 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
3059 | { | |
3060 | struct trace_array *tr = inode->i_private; | |
3061 | ||
3062 | trace_array_put(tr); | |
3063 | ||
3064 | return single_release(inode, file); | |
3065 | } | |
3066 | ||
bc0c38d1 SR |
3067 | static int tracing_open(struct inode *inode, struct file *file) |
3068 | { | |
6484c71c | 3069 | struct trace_array *tr = inode->i_private; |
85a2f9b4 SR |
3070 | struct trace_iterator *iter; |
3071 | int ret = 0; | |
bc0c38d1 | 3072 | |
ff451961 SRRH |
3073 | if (trace_array_get(tr) < 0) |
3074 | return -ENODEV; | |
3075 | ||
4acd4d00 | 3076 | /* If this file was open for write, then erase contents */ |
6484c71c ON |
3077 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
3078 | int cpu = tracing_get_cpu(inode); | |
3079 | ||
3080 | if (cpu == RING_BUFFER_ALL_CPUS) | |
12883efb | 3081 | tracing_reset_online_cpus(&tr->trace_buffer); |
4acd4d00 | 3082 | else |
6484c71c | 3083 | tracing_reset(&tr->trace_buffer, cpu); |
4acd4d00 | 3084 | } |
bc0c38d1 | 3085 | |
4acd4d00 | 3086 | if (file->f_mode & FMODE_READ) { |
6484c71c | 3087 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
3088 | if (IS_ERR(iter)) |
3089 | ret = PTR_ERR(iter); | |
3090 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
3091 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3092 | } | |
ff451961 SRRH |
3093 | |
3094 | if (ret < 0) | |
3095 | trace_array_put(tr); | |
3096 | ||
bc0c38d1 SR |
3097 | return ret; |
3098 | } | |
3099 | ||
e309b41d | 3100 | static void * |
bc0c38d1 SR |
3101 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3102 | { | |
f129e965 | 3103 | struct tracer *t = v; |
bc0c38d1 SR |
3104 | |
3105 | (*pos)++; | |
3106 | ||
3107 | if (t) | |
3108 | t = t->next; | |
3109 | ||
bc0c38d1 SR |
3110 | return t; |
3111 | } | |
3112 | ||
3113 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3114 | { | |
f129e965 | 3115 | struct tracer *t; |
bc0c38d1 SR |
3116 | loff_t l = 0; |
3117 | ||
3118 | mutex_lock(&trace_types_lock); | |
f129e965 | 3119 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
3120 | ; |
3121 | ||
3122 | return t; | |
3123 | } | |
3124 | ||
3125 | static void t_stop(struct seq_file *m, void *p) | |
3126 | { | |
3127 | mutex_unlock(&trace_types_lock); | |
3128 | } | |
3129 | ||
3130 | static int t_show(struct seq_file *m, void *v) | |
3131 | { | |
3132 | struct tracer *t = v; | |
3133 | ||
3134 | if (!t) | |
3135 | return 0; | |
3136 | ||
3137 | seq_printf(m, "%s", t->name); | |
3138 | if (t->next) | |
3139 | seq_putc(m, ' '); | |
3140 | else | |
3141 | seq_putc(m, '\n'); | |
3142 | ||
3143 | return 0; | |
3144 | } | |
3145 | ||
88e9d34c | 3146 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
3147 | .start = t_start, |
3148 | .next = t_next, | |
3149 | .stop = t_stop, | |
3150 | .show = t_show, | |
bc0c38d1 SR |
3151 | }; |
3152 | ||
3153 | static int show_traces_open(struct inode *inode, struct file *file) | |
3154 | { | |
60a11774 SR |
3155 | if (tracing_disabled) |
3156 | return -ENODEV; | |
3157 | ||
f129e965 | 3158 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
3159 | } |
3160 | ||
4acd4d00 SR |
3161 | static ssize_t |
3162 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
3163 | size_t count, loff_t *ppos) | |
3164 | { | |
3165 | return count; | |
3166 | } | |
3167 | ||
364829b1 SP |
3168 | static loff_t tracing_seek(struct file *file, loff_t offset, int origin) |
3169 | { | |
3170 | if (file->f_mode & FMODE_READ) | |
3171 | return seq_lseek(file, offset, origin); | |
3172 | else | |
3173 | return 0; | |
3174 | } | |
3175 | ||
5e2336a0 | 3176 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
3177 | .open = tracing_open, |
3178 | .read = seq_read, | |
4acd4d00 | 3179 | .write = tracing_write_stub, |
364829b1 | 3180 | .llseek = tracing_seek, |
4bf39a94 | 3181 | .release = tracing_release, |
bc0c38d1 SR |
3182 | }; |
3183 | ||
5e2336a0 | 3184 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
3185 | .open = show_traces_open, |
3186 | .read = seq_read, | |
3187 | .release = seq_release, | |
b444786f | 3188 | .llseek = seq_lseek, |
c7078de1 IM |
3189 | }; |
3190 | ||
36dfe925 IM |
3191 | /* |
3192 | * The tracer itself will not take this lock, but still we want | |
3193 | * to provide a consistent cpumask to user-space: | |
3194 | */ | |
3195 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
3196 | ||
3197 | /* | |
3198 | * Temporary storage for the character representation of the | |
3199 | * CPU bitmask (and one more byte for the newline): | |
3200 | */ | |
3201 | static char mask_str[NR_CPUS + 1]; | |
3202 | ||
c7078de1 IM |
3203 | static ssize_t |
3204 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
3205 | size_t count, loff_t *ppos) | |
3206 | { | |
ccfe9e42 | 3207 | struct trace_array *tr = file_inode(filp)->i_private; |
36dfe925 | 3208 | int len; |
c7078de1 IM |
3209 | |
3210 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 3211 | |
ccfe9e42 | 3212 | len = cpumask_scnprintf(mask_str, count, tr->tracing_cpumask); |
36dfe925 IM |
3213 | if (count - len < 2) { |
3214 | count = -EINVAL; | |
3215 | goto out_err; | |
3216 | } | |
3217 | len += sprintf(mask_str + len, "\n"); | |
3218 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
3219 | ||
3220 | out_err: | |
c7078de1 IM |
3221 | mutex_unlock(&tracing_cpumask_update_lock); |
3222 | ||
3223 | return count; | |
3224 | } | |
3225 | ||
3226 | static ssize_t | |
3227 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
3228 | size_t count, loff_t *ppos) | |
3229 | { | |
ccfe9e42 | 3230 | struct trace_array *tr = file_inode(filp)->i_private; |
9e01c1b7 | 3231 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 3232 | int err, cpu; |
9e01c1b7 RR |
3233 | |
3234 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
3235 | return -ENOMEM; | |
c7078de1 | 3236 | |
9e01c1b7 | 3237 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 3238 | if (err) |
36dfe925 IM |
3239 | goto err_unlock; |
3240 | ||
215368e8 LZ |
3241 | mutex_lock(&tracing_cpumask_update_lock); |
3242 | ||
a5e25883 | 3243 | local_irq_disable(); |
0199c4e6 | 3244 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 3245 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
3246 | /* |
3247 | * Increase/decrease the disabled counter if we are | |
3248 | * about to flip a bit in the cpumask: | |
3249 | */ | |
ccfe9e42 | 3250 | if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3251 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3252 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3253 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 3254 | } |
ccfe9e42 | 3255 | if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3256 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3257 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3258 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
3259 | } |
3260 | } | |
0199c4e6 | 3261 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 3262 | local_irq_enable(); |
36dfe925 | 3263 | |
ccfe9e42 | 3264 | cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
3265 | |
3266 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 3267 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
3268 | |
3269 | return count; | |
36dfe925 IM |
3270 | |
3271 | err_unlock: | |
215368e8 | 3272 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
3273 | |
3274 | return err; | |
c7078de1 IM |
3275 | } |
3276 | ||
5e2336a0 | 3277 | static const struct file_operations tracing_cpumask_fops = { |
ccfe9e42 | 3278 | .open = tracing_open_generic_tr, |
c7078de1 IM |
3279 | .read = tracing_cpumask_read, |
3280 | .write = tracing_cpumask_write, | |
ccfe9e42 | 3281 | .release = tracing_release_generic_tr, |
b444786f | 3282 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3283 | }; |
3284 | ||
fdb372ed | 3285 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 3286 | { |
d8e83d26 | 3287 | struct tracer_opt *trace_opts; |
2b6080f2 | 3288 | struct trace_array *tr = m->private; |
d8e83d26 | 3289 | u32 tracer_flags; |
d8e83d26 | 3290 | int i; |
adf9f195 | 3291 | |
d8e83d26 | 3292 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3293 | tracer_flags = tr->current_trace->flags->val; |
3294 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 3295 | |
bc0c38d1 SR |
3296 | for (i = 0; trace_options[i]; i++) { |
3297 | if (trace_flags & (1 << i)) | |
fdb372ed | 3298 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 3299 | else |
fdb372ed | 3300 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
3301 | } |
3302 | ||
adf9f195 FW |
3303 | for (i = 0; trace_opts[i].name; i++) { |
3304 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 3305 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 3306 | else |
fdb372ed | 3307 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 3308 | } |
d8e83d26 | 3309 | mutex_unlock(&trace_types_lock); |
adf9f195 | 3310 | |
fdb372ed | 3311 | return 0; |
bc0c38d1 | 3312 | } |
bc0c38d1 | 3313 | |
8d18eaaf LZ |
3314 | static int __set_tracer_option(struct tracer *trace, |
3315 | struct tracer_flags *tracer_flags, | |
3316 | struct tracer_opt *opts, int neg) | |
3317 | { | |
3318 | int ret; | |
bc0c38d1 | 3319 | |
8d18eaaf LZ |
3320 | ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); |
3321 | if (ret) | |
3322 | return ret; | |
3323 | ||
3324 | if (neg) | |
3325 | tracer_flags->val &= ~opts->bit; | |
3326 | else | |
3327 | tracer_flags->val |= opts->bit; | |
3328 | return 0; | |
bc0c38d1 SR |
3329 | } |
3330 | ||
adf9f195 FW |
3331 | /* Try to assign a tracer specific option */ |
3332 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
3333 | { | |
7770841e | 3334 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 3335 | struct tracer_opt *opts = NULL; |
8d18eaaf | 3336 | int i; |
adf9f195 | 3337 | |
7770841e Z |
3338 | for (i = 0; tracer_flags->opts[i].name; i++) { |
3339 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 3340 | |
8d18eaaf LZ |
3341 | if (strcmp(cmp, opts->name) == 0) |
3342 | return __set_tracer_option(trace, trace->flags, | |
3343 | opts, neg); | |
adf9f195 | 3344 | } |
adf9f195 | 3345 | |
8d18eaaf | 3346 | return -EINVAL; |
adf9f195 FW |
3347 | } |
3348 | ||
613f04a0 SRRH |
3349 | /* Some tracers require overwrite to stay enabled */ |
3350 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
3351 | { | |
3352 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
3353 | return -1; | |
3354 | ||
3355 | return 0; | |
3356 | } | |
3357 | ||
2b6080f2 | 3358 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
3359 | { |
3360 | /* do nothing if flag is already set */ | |
3361 | if (!!(trace_flags & mask) == !!enabled) | |
613f04a0 SRRH |
3362 | return 0; |
3363 | ||
3364 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 SR |
3365 | if (tr->current_trace->flag_changed) |
3366 | if (tr->current_trace->flag_changed(tr->current_trace, mask, !!enabled)) | |
613f04a0 | 3367 | return -EINVAL; |
af4617bd SR |
3368 | |
3369 | if (enabled) | |
3370 | trace_flags |= mask; | |
3371 | else | |
3372 | trace_flags &= ~mask; | |
e870e9a1 LZ |
3373 | |
3374 | if (mask == TRACE_ITER_RECORD_CMD) | |
3375 | trace_event_enable_cmd_record(enabled); | |
750912fa | 3376 | |
80902822 | 3377 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 3378 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 3379 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 3380 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
3381 | #endif |
3382 | } | |
81698831 SR |
3383 | |
3384 | if (mask == TRACE_ITER_PRINTK) | |
3385 | trace_printk_start_stop_comm(enabled); | |
613f04a0 SRRH |
3386 | |
3387 | return 0; | |
af4617bd SR |
3388 | } |
3389 | ||
2b6080f2 | 3390 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 3391 | { |
8d18eaaf | 3392 | char *cmp; |
bc0c38d1 | 3393 | int neg = 0; |
613f04a0 | 3394 | int ret = -ENODEV; |
bc0c38d1 SR |
3395 | int i; |
3396 | ||
7bcfaf54 | 3397 | cmp = strstrip(option); |
bc0c38d1 | 3398 | |
8d18eaaf | 3399 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3400 | neg = 1; |
3401 | cmp += 2; | |
3402 | } | |
3403 | ||
69d34da2 SRRH |
3404 | mutex_lock(&trace_types_lock); |
3405 | ||
bc0c38d1 | 3406 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3407 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3408 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3409 | break; |
3410 | } | |
3411 | } | |
adf9f195 FW |
3412 | |
3413 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3414 | if (!trace_options[i]) |
2b6080f2 | 3415 | ret = set_tracer_option(tr->current_trace, cmp, neg); |
69d34da2 SRRH |
3416 | |
3417 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3418 | |
7bcfaf54 SR |
3419 | return ret; |
3420 | } | |
3421 | ||
3422 | static ssize_t | |
3423 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3424 | size_t cnt, loff_t *ppos) | |
3425 | { | |
2b6080f2 SR |
3426 | struct seq_file *m = filp->private_data; |
3427 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3428 | char buf[64]; |
613f04a0 | 3429 | int ret; |
7bcfaf54 SR |
3430 | |
3431 | if (cnt >= sizeof(buf)) | |
3432 | return -EINVAL; | |
3433 | ||
3434 | if (copy_from_user(&buf, ubuf, cnt)) | |
3435 | return -EFAULT; | |
3436 | ||
a8dd2176 SR |
3437 | buf[cnt] = 0; |
3438 | ||
2b6080f2 | 3439 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
3440 | if (ret < 0) |
3441 | return ret; | |
7bcfaf54 | 3442 | |
cf8517cf | 3443 | *ppos += cnt; |
bc0c38d1 SR |
3444 | |
3445 | return cnt; | |
3446 | } | |
3447 | ||
fdb372ed LZ |
3448 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
3449 | { | |
7b85af63 | 3450 | struct trace_array *tr = inode->i_private; |
f77d09a3 | 3451 | int ret; |
7b85af63 | 3452 | |
fdb372ed LZ |
3453 | if (tracing_disabled) |
3454 | return -ENODEV; | |
2b6080f2 | 3455 | |
7b85af63 SRRH |
3456 | if (trace_array_get(tr) < 0) |
3457 | return -ENODEV; | |
3458 | ||
f77d09a3 AL |
3459 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
3460 | if (ret < 0) | |
3461 | trace_array_put(tr); | |
3462 | ||
3463 | return ret; | |
fdb372ed LZ |
3464 | } |
3465 | ||
5e2336a0 | 3466 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
3467 | .open = tracing_trace_options_open, |
3468 | .read = seq_read, | |
3469 | .llseek = seq_lseek, | |
7b85af63 | 3470 | .release = tracing_single_release_tr, |
ee6bce52 | 3471 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
3472 | }; |
3473 | ||
7bd2f24c IM |
3474 | static const char readme_msg[] = |
3475 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
3476 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
3477 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
3478 | " Important files:\n" | |
3479 | " trace\t\t\t- The static contents of the buffer\n" | |
3480 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
3481 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
3482 | " current_tracer\t- function and latency tracers\n" | |
3483 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
3484 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" | |
3485 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
3486 | " trace_clock\t\t-change the clock used to order events\n" | |
3487 | " local: Per cpu clock but may not be synced across CPUs\n" | |
3488 | " global: Synced across CPUs but slows tracing down.\n" | |
3489 | " counter: Not a clock, but just an increment\n" | |
3490 | " uptime: Jiffy counter from time of boot\n" | |
3491 | " perf: Same clock that perf events use\n" | |
3492 | #ifdef CONFIG_X86_64 | |
3493 | " x86-tsc: TSC cycle counter\n" | |
3494 | #endif | |
3495 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" | |
3496 | " tracing_cpumask\t- Limit which CPUs to trace\n" | |
3497 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
3498 | "\t\t\t Remove sub-buffer with rmdir\n" | |
3499 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
3500 | "\t\t\t Disable an option by adding a suffix 'no' to the option name\n" | |
3501 | #ifdef CONFIG_DYNAMIC_FTRACE | |
3502 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
3503 | " set_ftrace_filter\t- echo function name in here to only trace these functions\n" | |
3504 | " accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3505 | " modules: Can select a group via module\n" | |
3506 | " Format: :mod:<module-name>\n" | |
3507 | " example: echo :mod:ext3 > set_ftrace_filter\n" | |
3508 | " triggers: a command to perform when function is hit\n" | |
3509 | " Format: <function>:<trigger>[:count]\n" | |
3510 | " trigger: traceon, traceoff\n" | |
3511 | " enable_event:<system>:<event>\n" | |
3512 | " disable_event:<system>:<event>\n" | |
3513 | #ifdef CONFIG_STACKTRACE | |
3514 | " stacktrace\n" | |
3515 | #endif | |
3516 | #ifdef CONFIG_TRACER_SNAPSHOT | |
3517 | " snapshot\n" | |
3518 | #endif | |
3519 | " example: echo do_fault:traceoff > set_ftrace_filter\n" | |
3520 | " echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
3521 | " The first one will disable tracing every time do_fault is hit\n" | |
3522 | " The second will disable tracing at most 3 times when do_trap is hit\n" | |
3523 | " The first time do trap is hit and it disables tracing, the counter\n" | |
3524 | " will decrement to 2. If tracing is already disabled, the counter\n" | |
3525 | " will not decrement. It only decrements when the trigger did work\n" | |
3526 | " To remove trigger without count:\n" | |
3527 | " echo '!<function>:<trigger> > set_ftrace_filter\n" | |
3528 | " To remove trigger with a count:\n" | |
3529 | " echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
3530 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" | |
3531 | " accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3532 | " modules: Can select a group via module command :mod:\n" | |
3533 | " Does not accept triggers\n" | |
3534 | #endif /* CONFIG_DYNAMIC_FTRACE */ | |
3535 | #ifdef CONFIG_FUNCTION_TRACER | |
3536 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids (function)\n" | |
3537 | #endif | |
3538 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
3539 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
3540 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" | |
3541 | #endif | |
3542 | #ifdef CONFIG_TRACER_SNAPSHOT | |
3543 | "\n snapshot\t\t- Like 'trace' but shows the content of the static snapshot buffer\n" | |
3544 | "\t\t\t Read the contents for more information\n" | |
3545 | #endif | |
991821c8 | 3546 | #ifdef CONFIG_STACK_TRACER |
22f45649 SRRH |
3547 | " stack_trace\t\t- Shows the max stack trace when active\n" |
3548 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
3549 | "\t\t\t Write into this file to reset the max size (trigger a new trace)\n" | |
3550 | #ifdef CONFIG_DYNAMIC_FTRACE | |
3551 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace traces\n" | |
3552 | #endif | |
991821c8 | 3553 | #endif /* CONFIG_STACK_TRACER */ |
7bd2f24c IM |
3554 | ; |
3555 | ||
3556 | static ssize_t | |
3557 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
3558 | size_t cnt, loff_t *ppos) | |
3559 | { | |
3560 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
3561 | readme_msg, strlen(readme_msg)); | |
3562 | } | |
3563 | ||
5e2336a0 | 3564 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
3565 | .open = tracing_open_generic, |
3566 | .read = tracing_readme_read, | |
b444786f | 3567 | .llseek = generic_file_llseek, |
7bd2f24c IM |
3568 | }; |
3569 | ||
69abe6a5 AP |
3570 | static ssize_t |
3571 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
3572 | size_t cnt, loff_t *ppos) | |
3573 | { | |
3574 | char *buf_comm; | |
3575 | char *file_buf; | |
3576 | char *buf; | |
3577 | int len = 0; | |
3578 | int pid; | |
3579 | int i; | |
3580 | ||
3581 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
3582 | if (!file_buf) | |
3583 | return -ENOMEM; | |
3584 | ||
3585 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
3586 | if (!buf_comm) { | |
3587 | kfree(file_buf); | |
3588 | return -ENOMEM; | |
3589 | } | |
3590 | ||
3591 | buf = file_buf; | |
3592 | ||
3593 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
3594 | int r; | |
3595 | ||
3596 | pid = map_cmdline_to_pid[i]; | |
3597 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
3598 | continue; | |
3599 | ||
3600 | trace_find_cmdline(pid, buf_comm); | |
3601 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
3602 | buf += r; | |
3603 | len += r; | |
3604 | } | |
3605 | ||
3606 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
3607 | file_buf, len); | |
3608 | ||
3609 | kfree(file_buf); | |
3610 | kfree(buf_comm); | |
3611 | ||
3612 | return len; | |
3613 | } | |
3614 | ||
3615 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
3616 | .open = tracing_open_generic, | |
3617 | .read = tracing_saved_cmdlines_read, | |
b444786f | 3618 | .llseek = generic_file_llseek, |
69abe6a5 AP |
3619 | }; |
3620 | ||
bc0c38d1 SR |
3621 | static ssize_t |
3622 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
3623 | size_t cnt, loff_t *ppos) | |
3624 | { | |
2b6080f2 | 3625 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 3626 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
3627 | int r; |
3628 | ||
3629 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 3630 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
3631 | mutex_unlock(&trace_types_lock); |
3632 | ||
4bf39a94 | 3633 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3634 | } |
3635 | ||
b6f11df2 ACM |
3636 | int tracer_init(struct tracer *t, struct trace_array *tr) |
3637 | { | |
12883efb | 3638 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
3639 | return t->init(tr); |
3640 | } | |
3641 | ||
12883efb | 3642 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
3643 | { |
3644 | int cpu; | |
737223fb | 3645 | |
438ced17 | 3646 | for_each_tracing_cpu(cpu) |
12883efb | 3647 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
3648 | } |
3649 | ||
12883efb | 3650 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 3651 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
3652 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
3653 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
3654 | { |
3655 | int cpu, ret = 0; | |
3656 | ||
3657 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
3658 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
3659 | ret = ring_buffer_resize(trace_buf->buffer, |
3660 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
3661 | if (ret < 0) |
3662 | break; | |
12883efb SRRH |
3663 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
3664 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
3665 | } |
3666 | } else { | |
12883efb SRRH |
3667 | ret = ring_buffer_resize(trace_buf->buffer, |
3668 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 3669 | if (ret == 0) |
12883efb SRRH |
3670 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
3671 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
3672 | } |
3673 | ||
3674 | return ret; | |
3675 | } | |
12883efb | 3676 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 3677 | |
2b6080f2 SR |
3678 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
3679 | unsigned long size, int cpu) | |
73c5162a SR |
3680 | { |
3681 | int ret; | |
3682 | ||
3683 | /* | |
3684 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3685 | * we use the size that was given, and we can forget about |
3686 | * expanding it later. | |
73c5162a | 3687 | */ |
55034cd6 | 3688 | ring_buffer_expanded = true; |
73c5162a | 3689 | |
b382ede6 | 3690 | /* May be called before buffers are initialized */ |
12883efb | 3691 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
3692 | return 0; |
3693 | ||
12883efb | 3694 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
3695 | if (ret < 0) |
3696 | return ret; | |
3697 | ||
12883efb | 3698 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
3699 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
3700 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
3701 | goto out; |
3702 | ||
12883efb | 3703 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 3704 | if (ret < 0) { |
12883efb SRRH |
3705 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
3706 | &tr->trace_buffer, cpu); | |
73c5162a | 3707 | if (r < 0) { |
a123c52b SR |
3708 | /* |
3709 | * AARGH! We are left with different | |
3710 | * size max buffer!!!! | |
3711 | * The max buffer is our "snapshot" buffer. | |
3712 | * When a tracer needs a snapshot (one of the | |
3713 | * latency tracers), it swaps the max buffer | |
3714 | * with the saved snap shot. We succeeded to | |
3715 | * update the size of the main buffer, but failed to | |
3716 | * update the size of the max buffer. But when we tried | |
3717 | * to reset the main buffer to the original size, we | |
3718 | * failed there too. This is very unlikely to | |
3719 | * happen, but if it does, warn and kill all | |
3720 | * tracing. | |
3721 | */ | |
73c5162a SR |
3722 | WARN_ON(1); |
3723 | tracing_disabled = 1; | |
3724 | } | |
3725 | return ret; | |
3726 | } | |
3727 | ||
438ced17 | 3728 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3729 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 3730 | else |
12883efb | 3731 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 3732 | |
ef710e10 | 3733 | out: |
12883efb SRRH |
3734 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
3735 | ||
438ced17 | 3736 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3737 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 3738 | else |
12883efb | 3739 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
3740 | |
3741 | return ret; | |
3742 | } | |
3743 | ||
2b6080f2 SR |
3744 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
3745 | unsigned long size, int cpu_id) | |
4f271a2a | 3746 | { |
83f40318 | 3747 | int ret = size; |
4f271a2a VN |
3748 | |
3749 | mutex_lock(&trace_types_lock); | |
3750 | ||
438ced17 VN |
3751 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
3752 | /* make sure, this cpu is enabled in the mask */ | |
3753 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
3754 | ret = -EINVAL; | |
3755 | goto out; | |
3756 | } | |
3757 | } | |
4f271a2a | 3758 | |
2b6080f2 | 3759 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
3760 | if (ret < 0) |
3761 | ret = -ENOMEM; | |
3762 | ||
438ced17 | 3763 | out: |
4f271a2a VN |
3764 | mutex_unlock(&trace_types_lock); |
3765 | ||
3766 | return ret; | |
3767 | } | |
3768 | ||
ef710e10 | 3769 | |
1852fcce SR |
3770 | /** |
3771 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
3772 | * | |
3773 | * To save on memory when the tracing is never used on a system with it | |
3774 | * configured in. The ring buffers are set to a minimum size. But once | |
3775 | * a user starts to use the tracing facility, then they need to grow | |
3776 | * to their default size. | |
3777 | * | |
3778 | * This function is to be called when a tracer is about to be used. | |
3779 | */ | |
3780 | int tracing_update_buffers(void) | |
3781 | { | |
3782 | int ret = 0; | |
3783 | ||
1027fcb2 | 3784 | mutex_lock(&trace_types_lock); |
1852fcce | 3785 | if (!ring_buffer_expanded) |
2b6080f2 | 3786 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 3787 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 3788 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
3789 | |
3790 | return ret; | |
3791 | } | |
3792 | ||
577b785f SR |
3793 | struct trace_option_dentry; |
3794 | ||
3795 | static struct trace_option_dentry * | |
2b6080f2 | 3796 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f SR |
3797 | |
3798 | static void | |
3799 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
3800 | ||
b2821ae6 | 3801 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 3802 | { |
577b785f | 3803 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
3804 | struct trace_array *tr = &global_trace; |
3805 | struct tracer *t; | |
12883efb | 3806 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 3807 | bool had_max_tr; |
12883efb | 3808 | #endif |
d9e54076 | 3809 | int ret = 0; |
bc0c38d1 | 3810 | |
1027fcb2 SR |
3811 | mutex_lock(&trace_types_lock); |
3812 | ||
73c5162a | 3813 | if (!ring_buffer_expanded) { |
2b6080f2 | 3814 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 3815 | RING_BUFFER_ALL_CPUS); |
73c5162a | 3816 | if (ret < 0) |
59f586db | 3817 | goto out; |
73c5162a SR |
3818 | ret = 0; |
3819 | } | |
3820 | ||
bc0c38d1 SR |
3821 | for (t = trace_types; t; t = t->next) { |
3822 | if (strcmp(t->name, buf) == 0) | |
3823 | break; | |
3824 | } | |
c2931e05 FW |
3825 | if (!t) { |
3826 | ret = -EINVAL; | |
3827 | goto out; | |
3828 | } | |
2b6080f2 | 3829 | if (t == tr->current_trace) |
bc0c38d1 SR |
3830 | goto out; |
3831 | ||
9f029e83 | 3832 | trace_branch_disable(); |
613f04a0 | 3833 | |
2b6080f2 | 3834 | tr->current_trace->enabled = false; |
613f04a0 | 3835 | |
2b6080f2 SR |
3836 | if (tr->current_trace->reset) |
3837 | tr->current_trace->reset(tr); | |
34600f0e | 3838 | |
12883efb | 3839 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 3840 | tr->current_trace = &nop_trace; |
34600f0e | 3841 | |
45ad21ca SRRH |
3842 | #ifdef CONFIG_TRACER_MAX_TRACE |
3843 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
3844 | |
3845 | if (had_max_tr && !t->use_max_tr) { | |
3846 | /* | |
3847 | * We need to make sure that the update_max_tr sees that | |
3848 | * current_trace changed to nop_trace to keep it from | |
3849 | * swapping the buffers after we resize it. | |
3850 | * The update_max_tr is called from interrupts disabled | |
3851 | * so a synchronized_sched() is sufficient. | |
3852 | */ | |
3853 | synchronize_sched(); | |
3209cff4 | 3854 | free_snapshot(tr); |
ef710e10 | 3855 | } |
12883efb | 3856 | #endif |
577b785f SR |
3857 | destroy_trace_option_files(topts); |
3858 | ||
2b6080f2 | 3859 | topts = create_trace_option_files(tr, t); |
12883efb SRRH |
3860 | |
3861 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 3862 | if (t->use_max_tr && !had_max_tr) { |
3209cff4 | 3863 | ret = alloc_snapshot(tr); |
d60da506 HT |
3864 | if (ret < 0) |
3865 | goto out; | |
ef710e10 | 3866 | } |
12883efb | 3867 | #endif |
577b785f | 3868 | |
1c80025a | 3869 | if (t->init) { |
b6f11df2 | 3870 | ret = tracer_init(t, tr); |
1c80025a FW |
3871 | if (ret) |
3872 | goto out; | |
3873 | } | |
bc0c38d1 | 3874 | |
2b6080f2 SR |
3875 | tr->current_trace = t; |
3876 | tr->current_trace->enabled = true; | |
9f029e83 | 3877 | trace_branch_enable(tr); |
bc0c38d1 SR |
3878 | out: |
3879 | mutex_unlock(&trace_types_lock); | |
3880 | ||
d9e54076 PZ |
3881 | return ret; |
3882 | } | |
3883 | ||
3884 | static ssize_t | |
3885 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
3886 | size_t cnt, loff_t *ppos) | |
3887 | { | |
ee6c2c1b | 3888 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
3889 | int i; |
3890 | size_t ret; | |
e6e7a65a FW |
3891 | int err; |
3892 | ||
3893 | ret = cnt; | |
d9e54076 | 3894 | |
ee6c2c1b LZ |
3895 | if (cnt > MAX_TRACER_SIZE) |
3896 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
3897 | |
3898 | if (copy_from_user(&buf, ubuf, cnt)) | |
3899 | return -EFAULT; | |
3900 | ||
3901 | buf[cnt] = 0; | |
3902 | ||
3903 | /* strip ending whitespace. */ | |
3904 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
3905 | buf[i] = 0; | |
3906 | ||
e6e7a65a FW |
3907 | err = tracing_set_tracer(buf); |
3908 | if (err) | |
3909 | return err; | |
d9e54076 | 3910 | |
cf8517cf | 3911 | *ppos += ret; |
bc0c38d1 | 3912 | |
c2931e05 | 3913 | return ret; |
bc0c38d1 SR |
3914 | } |
3915 | ||
3916 | static ssize_t | |
3917 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
3918 | size_t cnt, loff_t *ppos) | |
3919 | { | |
3920 | unsigned long *ptr = filp->private_data; | |
3921 | char buf[64]; | |
3922 | int r; | |
3923 | ||
cffae437 | 3924 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 3925 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
3926 | if (r > sizeof(buf)) |
3927 | r = sizeof(buf); | |
4bf39a94 | 3928 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3929 | } |
3930 | ||
3931 | static ssize_t | |
3932 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
3933 | size_t cnt, loff_t *ppos) | |
3934 | { | |
5e39841c | 3935 | unsigned long *ptr = filp->private_data; |
5e39841c | 3936 | unsigned long val; |
c6caeeb1 | 3937 | int ret; |
bc0c38d1 | 3938 | |
22fe9b54 PH |
3939 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3940 | if (ret) | |
c6caeeb1 | 3941 | return ret; |
bc0c38d1 SR |
3942 | |
3943 | *ptr = val * 1000; | |
3944 | ||
3945 | return cnt; | |
3946 | } | |
3947 | ||
b3806b43 SR |
3948 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
3949 | { | |
15544209 | 3950 | struct trace_array *tr = inode->i_private; |
b3806b43 | 3951 | struct trace_iterator *iter; |
b04cc6b1 | 3952 | int ret = 0; |
b3806b43 SR |
3953 | |
3954 | if (tracing_disabled) | |
3955 | return -ENODEV; | |
3956 | ||
7b85af63 SRRH |
3957 | if (trace_array_get(tr) < 0) |
3958 | return -ENODEV; | |
3959 | ||
b04cc6b1 FW |
3960 | mutex_lock(&trace_types_lock); |
3961 | ||
b3806b43 SR |
3962 | /* create a buffer to store the information to pass to userspace */ |
3963 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
3964 | if (!iter) { |
3965 | ret = -ENOMEM; | |
f77d09a3 | 3966 | __trace_array_put(tr); |
b04cc6b1 FW |
3967 | goto out; |
3968 | } | |
b3806b43 | 3969 | |
d7350c3f FW |
3970 | /* |
3971 | * We make a copy of the current tracer to avoid concurrent | |
3972 | * changes on it while we are reading. | |
3973 | */ | |
3974 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
3975 | if (!iter->trace) { | |
3976 | ret = -ENOMEM; | |
3977 | goto fail; | |
3978 | } | |
2b6080f2 | 3979 | *iter->trace = *tr->current_trace; |
d7350c3f | 3980 | |
4462344e | 3981 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 3982 | ret = -ENOMEM; |
d7350c3f | 3983 | goto fail; |
4462344e RR |
3984 | } |
3985 | ||
a309720c | 3986 | /* trace pipe does not show start of buffer */ |
4462344e | 3987 | cpumask_setall(iter->started); |
a309720c | 3988 | |
112f38a7 SR |
3989 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
3990 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3991 | ||
8be0709f | 3992 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 3993 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
3994 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
3995 | ||
15544209 ON |
3996 | iter->tr = tr; |
3997 | iter->trace_buffer = &tr->trace_buffer; | |
3998 | iter->cpu_file = tracing_get_cpu(inode); | |
d7350c3f | 3999 | mutex_init(&iter->mutex); |
b3806b43 SR |
4000 | filp->private_data = iter; |
4001 | ||
107bad8b SR |
4002 | if (iter->trace->pipe_open) |
4003 | iter->trace->pipe_open(iter); | |
107bad8b | 4004 | |
b444786f | 4005 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
4006 | out: |
4007 | mutex_unlock(&trace_types_lock); | |
4008 | return ret; | |
d7350c3f FW |
4009 | |
4010 | fail: | |
4011 | kfree(iter->trace); | |
4012 | kfree(iter); | |
7b85af63 | 4013 | __trace_array_put(tr); |
d7350c3f FW |
4014 | mutex_unlock(&trace_types_lock); |
4015 | return ret; | |
b3806b43 SR |
4016 | } |
4017 | ||
4018 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
4019 | { | |
4020 | struct trace_iterator *iter = file->private_data; | |
15544209 | 4021 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4022 | |
b04cc6b1 FW |
4023 | mutex_lock(&trace_types_lock); |
4024 | ||
29bf4a5e | 4025 | if (iter->trace->pipe_close) |
c521efd1 SR |
4026 | iter->trace->pipe_close(iter); |
4027 | ||
b04cc6b1 FW |
4028 | mutex_unlock(&trace_types_lock); |
4029 | ||
4462344e | 4030 | free_cpumask_var(iter->started); |
d7350c3f FW |
4031 | mutex_destroy(&iter->mutex); |
4032 | kfree(iter->trace); | |
b3806b43 | 4033 | kfree(iter); |
b3806b43 | 4034 | |
7b85af63 SRRH |
4035 | trace_array_put(tr); |
4036 | ||
b3806b43 SR |
4037 | return 0; |
4038 | } | |
4039 | ||
2a2cc8f7 | 4040 | static unsigned int |
cc60cdc9 | 4041 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 4042 | { |
15693458 SRRH |
4043 | /* Iterators are static, they should be filled or empty */ |
4044 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
4045 | return POLLIN | POLLRDNORM; | |
2a2cc8f7 | 4046 | |
15693458 | 4047 | if (trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
4048 | /* |
4049 | * Always select as readable when in blocking mode | |
4050 | */ | |
4051 | return POLLIN | POLLRDNORM; | |
15693458 | 4052 | else |
12883efb | 4053 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 4054 | filp, poll_table); |
2a2cc8f7 | 4055 | } |
2a2cc8f7 | 4056 | |
cc60cdc9 SR |
4057 | static unsigned int |
4058 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
4059 | { | |
4060 | struct trace_iterator *iter = filp->private_data; | |
4061 | ||
4062 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
4063 | } |
4064 | ||
6eaaa5d5 FW |
4065 | /* |
4066 | * This is a make-shift waitqueue. | |
4067 | * A tracer might use this callback on some rare cases: | |
4068 | * | |
4069 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
4070 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
4071 | * 2) the function tracers, trace all functions, we don't want | |
4072 | * the overhead of calling wake_up and friends | |
4073 | * (and tracing them too) | |
4074 | * | |
4075 | * Anyway, this is really very primitive wakeup. | |
4076 | */ | |
4077 | void poll_wait_pipe(struct trace_iterator *iter) | |
4078 | { | |
4079 | set_current_state(TASK_INTERRUPTIBLE); | |
4080 | /* sleep for 100 msecs, and try again. */ | |
4081 | schedule_timeout(HZ / 10); | |
4082 | } | |
4083 | ||
ff98781b EGM |
4084 | /* Must be called with trace_types_lock mutex held. */ |
4085 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
4086 | { |
4087 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 4088 | |
b3806b43 | 4089 | while (trace_empty(iter)) { |
2dc8f095 | 4090 | |
107bad8b | 4091 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 4092 | return -EAGAIN; |
107bad8b | 4093 | } |
2dc8f095 | 4094 | |
d7350c3f | 4095 | mutex_unlock(&iter->mutex); |
107bad8b | 4096 | |
6eaaa5d5 | 4097 | iter->trace->wait_pipe(iter); |
b3806b43 | 4098 | |
d7350c3f | 4099 | mutex_lock(&iter->mutex); |
107bad8b | 4100 | |
6eaaa5d5 | 4101 | if (signal_pending(current)) |
ff98781b | 4102 | return -EINTR; |
b3806b43 SR |
4103 | |
4104 | /* | |
250bfd3d | 4105 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
4106 | * We still block if tracing is disabled, but we have never |
4107 | * read anything. This allows a user to cat this file, and | |
4108 | * then enable tracing. But after we have read something, | |
4109 | * we give an EOF when tracing is again disabled. | |
4110 | * | |
4111 | * iter->pos will be 0 if we haven't read anything. | |
4112 | */ | |
10246fa3 | 4113 | if (!tracing_is_on() && iter->pos) |
b3806b43 | 4114 | break; |
b3806b43 SR |
4115 | } |
4116 | ||
ff98781b EGM |
4117 | return 1; |
4118 | } | |
4119 | ||
4120 | /* | |
4121 | * Consumer reader. | |
4122 | */ | |
4123 | static ssize_t | |
4124 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
4125 | size_t cnt, loff_t *ppos) | |
4126 | { | |
4127 | struct trace_iterator *iter = filp->private_data; | |
2b6080f2 | 4128 | struct trace_array *tr = iter->tr; |
ff98781b EGM |
4129 | ssize_t sret; |
4130 | ||
4131 | /* return any leftover data */ | |
4132 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
4133 | if (sret != -EBUSY) | |
4134 | return sret; | |
4135 | ||
f9520750 | 4136 | trace_seq_init(&iter->seq); |
ff98781b | 4137 | |
d7350c3f | 4138 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 4139 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4140 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4141 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4142 | mutex_unlock(&trace_types_lock); |
4143 | ||
4144 | /* | |
4145 | * Avoid more than one consumer on a single file descriptor | |
4146 | * This is just a matter of traces coherency, the ring buffer itself | |
4147 | * is protected. | |
4148 | */ | |
4149 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
4150 | if (iter->trace->read) { |
4151 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
4152 | if (sret) | |
4153 | goto out; | |
4154 | } | |
4155 | ||
4156 | waitagain: | |
4157 | sret = tracing_wait_pipe(filp); | |
4158 | if (sret <= 0) | |
4159 | goto out; | |
4160 | ||
b3806b43 | 4161 | /* stop when tracing is finished */ |
ff98781b EGM |
4162 | if (trace_empty(iter)) { |
4163 | sret = 0; | |
107bad8b | 4164 | goto out; |
ff98781b | 4165 | } |
b3806b43 SR |
4166 | |
4167 | if (cnt >= PAGE_SIZE) | |
4168 | cnt = PAGE_SIZE - 1; | |
4169 | ||
53d0aa77 | 4170 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
4171 | memset(&iter->seq, 0, |
4172 | sizeof(struct trace_iterator) - | |
4173 | offsetof(struct trace_iterator, seq)); | |
ed5467da | 4174 | cpumask_clear(iter->started); |
4823ed7e | 4175 | iter->pos = -1; |
b3806b43 | 4176 | |
4f535968 | 4177 | trace_event_read_lock(); |
7e53bd42 | 4178 | trace_access_lock(iter->cpu_file); |
955b61e5 | 4179 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 4180 | enum print_line_t ret; |
088b1e42 SR |
4181 | int len = iter->seq.len; |
4182 | ||
f9896bf3 | 4183 | ret = print_trace_line(iter); |
2c4f035f | 4184 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
4185 | /* don't print partial lines */ |
4186 | iter->seq.len = len; | |
b3806b43 | 4187 | break; |
088b1e42 | 4188 | } |
b91facc3 FW |
4189 | if (ret != TRACE_TYPE_NO_CONSUME) |
4190 | trace_consume(iter); | |
b3806b43 SR |
4191 | |
4192 | if (iter->seq.len >= cnt) | |
4193 | break; | |
ee5e51f5 JO |
4194 | |
4195 | /* | |
4196 | * Setting the full flag means we reached the trace_seq buffer | |
4197 | * size and we should leave by partial output condition above. | |
4198 | * One of the trace_seq_* functions is not used properly. | |
4199 | */ | |
4200 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
4201 | iter->ent->type); | |
b3806b43 | 4202 | } |
7e53bd42 | 4203 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4204 | trace_event_read_unlock(); |
b3806b43 | 4205 | |
b3806b43 | 4206 | /* Now copy what we have to the user */ |
6c6c2796 PP |
4207 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
4208 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 4209 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
4210 | |
4211 | /* | |
25985edc | 4212 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
4213 | * entries, go back to wait for more entries. |
4214 | */ | |
6c6c2796 | 4215 | if (sret == -EBUSY) |
9ff4b974 | 4216 | goto waitagain; |
b3806b43 | 4217 | |
107bad8b | 4218 | out: |
d7350c3f | 4219 | mutex_unlock(&iter->mutex); |
107bad8b | 4220 | |
6c6c2796 | 4221 | return sret; |
b3806b43 SR |
4222 | } |
4223 | ||
3c56819b EGM |
4224 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
4225 | struct pipe_buffer *buf) | |
4226 | { | |
4227 | __free_page(buf->page); | |
4228 | } | |
4229 | ||
4230 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
4231 | unsigned int idx) | |
4232 | { | |
4233 | __free_page(spd->pages[idx]); | |
4234 | } | |
4235 | ||
28dfef8f | 4236 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
4237 | .can_merge = 0, |
4238 | .map = generic_pipe_buf_map, | |
4239 | .unmap = generic_pipe_buf_unmap, | |
4240 | .confirm = generic_pipe_buf_confirm, | |
4241 | .release = tracing_pipe_buf_release, | |
4242 | .steal = generic_pipe_buf_steal, | |
4243 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
4244 | }; |
4245 | ||
34cd4998 | 4246 | static size_t |
fa7c7f6e | 4247 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
4248 | { |
4249 | size_t count; | |
4250 | int ret; | |
4251 | ||
4252 | /* Seq buffer is page-sized, exactly what we need. */ | |
4253 | for (;;) { | |
4254 | count = iter->seq.len; | |
4255 | ret = print_trace_line(iter); | |
4256 | count = iter->seq.len - count; | |
4257 | if (rem < count) { | |
4258 | rem = 0; | |
4259 | iter->seq.len -= count; | |
4260 | break; | |
4261 | } | |
4262 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
4263 | iter->seq.len -= count; | |
4264 | break; | |
4265 | } | |
4266 | ||
74e7ff8c LJ |
4267 | if (ret != TRACE_TYPE_NO_CONSUME) |
4268 | trace_consume(iter); | |
34cd4998 | 4269 | rem -= count; |
955b61e5 | 4270 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
4271 | rem = 0; |
4272 | iter->ent = NULL; | |
4273 | break; | |
4274 | } | |
4275 | } | |
4276 | ||
4277 | return rem; | |
4278 | } | |
4279 | ||
3c56819b EGM |
4280 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
4281 | loff_t *ppos, | |
4282 | struct pipe_inode_info *pipe, | |
4283 | size_t len, | |
4284 | unsigned int flags) | |
4285 | { | |
35f3d14d JA |
4286 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
4287 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
4288 | struct trace_iterator *iter = filp->private_data; |
4289 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
4290 | .pages = pages_def, |
4291 | .partial = partial_def, | |
34cd4998 | 4292 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 4293 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
4294 | .flags = flags, |
4295 | .ops = &tracing_pipe_buf_ops, | |
4296 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 4297 | }; |
2b6080f2 | 4298 | struct trace_array *tr = iter->tr; |
3c56819b | 4299 | ssize_t ret; |
34cd4998 | 4300 | size_t rem; |
3c56819b EGM |
4301 | unsigned int i; |
4302 | ||
35f3d14d JA |
4303 | if (splice_grow_spd(pipe, &spd)) |
4304 | return -ENOMEM; | |
4305 | ||
d7350c3f | 4306 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 4307 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4308 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4309 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4310 | mutex_unlock(&trace_types_lock); |
4311 | ||
4312 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
4313 | |
4314 | if (iter->trace->splice_read) { | |
4315 | ret = iter->trace->splice_read(iter, filp, | |
4316 | ppos, pipe, len, flags); | |
4317 | if (ret) | |
34cd4998 | 4318 | goto out_err; |
3c56819b EGM |
4319 | } |
4320 | ||
4321 | ret = tracing_wait_pipe(filp); | |
4322 | if (ret <= 0) | |
34cd4998 | 4323 | goto out_err; |
3c56819b | 4324 | |
955b61e5 | 4325 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 4326 | ret = -EFAULT; |
34cd4998 | 4327 | goto out_err; |
3c56819b EGM |
4328 | } |
4329 | ||
4f535968 | 4330 | trace_event_read_lock(); |
7e53bd42 | 4331 | trace_access_lock(iter->cpu_file); |
4f535968 | 4332 | |
3c56819b | 4333 | /* Fill as many pages as possible. */ |
35f3d14d JA |
4334 | for (i = 0, rem = len; i < pipe->buffers && rem; i++) { |
4335 | spd.pages[i] = alloc_page(GFP_KERNEL); | |
4336 | if (!spd.pages[i]) | |
34cd4998 | 4337 | break; |
3c56819b | 4338 | |
fa7c7f6e | 4339 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
4340 | |
4341 | /* Copy the data into the page, so we can start over. */ | |
4342 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 4343 | page_address(spd.pages[i]), |
3c56819b EGM |
4344 | iter->seq.len); |
4345 | if (ret < 0) { | |
35f3d14d | 4346 | __free_page(spd.pages[i]); |
3c56819b EGM |
4347 | break; |
4348 | } | |
35f3d14d JA |
4349 | spd.partial[i].offset = 0; |
4350 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 4351 | |
f9520750 | 4352 | trace_seq_init(&iter->seq); |
3c56819b EGM |
4353 | } |
4354 | ||
7e53bd42 | 4355 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4356 | trace_event_read_unlock(); |
d7350c3f | 4357 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
4358 | |
4359 | spd.nr_pages = i; | |
4360 | ||
35f3d14d JA |
4361 | ret = splice_to_pipe(pipe, &spd); |
4362 | out: | |
047fe360 | 4363 | splice_shrink_spd(&spd); |
35f3d14d | 4364 | return ret; |
3c56819b | 4365 | |
34cd4998 | 4366 | out_err: |
d7350c3f | 4367 | mutex_unlock(&iter->mutex); |
35f3d14d | 4368 | goto out; |
3c56819b EGM |
4369 | } |
4370 | ||
a98a3c3f SR |
4371 | static ssize_t |
4372 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
4373 | size_t cnt, loff_t *ppos) | |
4374 | { | |
0bc392ee ON |
4375 | struct inode *inode = file_inode(filp); |
4376 | struct trace_array *tr = inode->i_private; | |
4377 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
4378 | char buf[64]; |
4379 | int r = 0; | |
4380 | ssize_t ret; | |
a98a3c3f | 4381 | |
db526ca3 | 4382 | mutex_lock(&trace_types_lock); |
438ced17 | 4383 | |
0bc392ee | 4384 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
4385 | int cpu, buf_size_same; |
4386 | unsigned long size; | |
4387 | ||
4388 | size = 0; | |
4389 | buf_size_same = 1; | |
4390 | /* check if all cpu sizes are same */ | |
4391 | for_each_tracing_cpu(cpu) { | |
4392 | /* fill in the size from first enabled cpu */ | |
4393 | if (size == 0) | |
12883efb SRRH |
4394 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
4395 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
4396 | buf_size_same = 0; |
4397 | break; | |
4398 | } | |
4399 | } | |
4400 | ||
4401 | if (buf_size_same) { | |
4402 | if (!ring_buffer_expanded) | |
4403 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
4404 | size >> 10, | |
4405 | trace_buf_size >> 10); | |
4406 | else | |
4407 | r = sprintf(buf, "%lu\n", size >> 10); | |
4408 | } else | |
4409 | r = sprintf(buf, "X\n"); | |
4410 | } else | |
0bc392ee | 4411 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10); |
438ced17 | 4412 | |
db526ca3 SR |
4413 | mutex_unlock(&trace_types_lock); |
4414 | ||
438ced17 VN |
4415 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
4416 | return ret; | |
a98a3c3f SR |
4417 | } |
4418 | ||
4419 | static ssize_t | |
4420 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
4421 | size_t cnt, loff_t *ppos) | |
4422 | { | |
0bc392ee ON |
4423 | struct inode *inode = file_inode(filp); |
4424 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 4425 | unsigned long val; |
4f271a2a | 4426 | int ret; |
a98a3c3f | 4427 | |
22fe9b54 PH |
4428 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4429 | if (ret) | |
c6caeeb1 | 4430 | return ret; |
a98a3c3f SR |
4431 | |
4432 | /* must have at least 1 entry */ | |
4433 | if (!val) | |
4434 | return -EINVAL; | |
4435 | ||
1696b2b0 SR |
4436 | /* value is in KB */ |
4437 | val <<= 10; | |
0bc392ee | 4438 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
4439 | if (ret < 0) |
4440 | return ret; | |
a98a3c3f | 4441 | |
cf8517cf | 4442 | *ppos += cnt; |
a98a3c3f | 4443 | |
4f271a2a VN |
4444 | return cnt; |
4445 | } | |
bf5e6519 | 4446 | |
f81ab074 VN |
4447 | static ssize_t |
4448 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
4449 | size_t cnt, loff_t *ppos) | |
4450 | { | |
4451 | struct trace_array *tr = filp->private_data; | |
4452 | char buf[64]; | |
4453 | int r, cpu; | |
4454 | unsigned long size = 0, expanded_size = 0; | |
4455 | ||
4456 | mutex_lock(&trace_types_lock); | |
4457 | for_each_tracing_cpu(cpu) { | |
12883efb | 4458 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
4459 | if (!ring_buffer_expanded) |
4460 | expanded_size += trace_buf_size >> 10; | |
4461 | } | |
4462 | if (ring_buffer_expanded) | |
4463 | r = sprintf(buf, "%lu\n", size); | |
4464 | else | |
4465 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
4466 | mutex_unlock(&trace_types_lock); | |
4467 | ||
4468 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4469 | } | |
4470 | ||
4f271a2a VN |
4471 | static ssize_t |
4472 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
4473 | size_t cnt, loff_t *ppos) | |
4474 | { | |
4475 | /* | |
4476 | * There is no need to read what the user has written, this function | |
4477 | * is just to make sure that there is no error when "echo" is used | |
4478 | */ | |
4479 | ||
4480 | *ppos += cnt; | |
a98a3c3f SR |
4481 | |
4482 | return cnt; | |
4483 | } | |
4484 | ||
4f271a2a VN |
4485 | static int |
4486 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
4487 | { | |
2b6080f2 SR |
4488 | struct trace_array *tr = inode->i_private; |
4489 | ||
cf30cf67 SR |
4490 | /* disable tracing ? */ |
4491 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
711e1243 | 4492 | tracer_tracing_off(tr); |
4f271a2a | 4493 | /* resize the ring buffer to 0 */ |
2b6080f2 | 4494 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 4495 | |
7b85af63 SRRH |
4496 | trace_array_put(tr); |
4497 | ||
4f271a2a VN |
4498 | return 0; |
4499 | } | |
4500 | ||
5bf9a1ee PP |
4501 | static ssize_t |
4502 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
4503 | size_t cnt, loff_t *fpos) | |
4504 | { | |
d696b58c | 4505 | unsigned long addr = (unsigned long)ubuf; |
2d71619c | 4506 | struct trace_array *tr = filp->private_data; |
d696b58c SR |
4507 | struct ring_buffer_event *event; |
4508 | struct ring_buffer *buffer; | |
4509 | struct print_entry *entry; | |
4510 | unsigned long irq_flags; | |
4511 | struct page *pages[2]; | |
6edb2a8a | 4512 | void *map_page[2]; |
d696b58c SR |
4513 | int nr_pages = 1; |
4514 | ssize_t written; | |
d696b58c SR |
4515 | int offset; |
4516 | int size; | |
4517 | int len; | |
4518 | int ret; | |
6edb2a8a | 4519 | int i; |
5bf9a1ee | 4520 | |
c76f0694 | 4521 | if (tracing_disabled) |
5bf9a1ee PP |
4522 | return -EINVAL; |
4523 | ||
5224c3a3 MSB |
4524 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
4525 | return -EINVAL; | |
4526 | ||
5bf9a1ee PP |
4527 | if (cnt > TRACE_BUF_SIZE) |
4528 | cnt = TRACE_BUF_SIZE; | |
4529 | ||
d696b58c SR |
4530 | /* |
4531 | * Userspace is injecting traces into the kernel trace buffer. | |
4532 | * We want to be as non intrusive as possible. | |
4533 | * To do so, we do not want to allocate any special buffers | |
4534 | * or take any locks, but instead write the userspace data | |
4535 | * straight into the ring buffer. | |
4536 | * | |
4537 | * First we need to pin the userspace buffer into memory, | |
4538 | * which, most likely it is, because it just referenced it. | |
4539 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
4540 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
4541 | * pages directly. We then write the data directly into the | |
4542 | * ring buffer. | |
4543 | */ | |
4544 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 4545 | |
d696b58c SR |
4546 | /* check if we cross pages */ |
4547 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
4548 | nr_pages = 2; | |
4549 | ||
4550 | offset = addr & (PAGE_SIZE - 1); | |
4551 | addr &= PAGE_MASK; | |
4552 | ||
4553 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
4554 | if (ret < nr_pages) { | |
4555 | while (--ret >= 0) | |
4556 | put_page(pages[ret]); | |
4557 | written = -EFAULT; | |
4558 | goto out; | |
5bf9a1ee | 4559 | } |
d696b58c | 4560 | |
6edb2a8a SR |
4561 | for (i = 0; i < nr_pages; i++) |
4562 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
4563 | |
4564 | local_save_flags(irq_flags); | |
4565 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
2d71619c | 4566 | buffer = tr->trace_buffer.buffer; |
d696b58c SR |
4567 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
4568 | irq_flags, preempt_count()); | |
4569 | if (!event) { | |
4570 | /* Ring buffer disabled, return as if not open for write */ | |
4571 | written = -EBADF; | |
4572 | goto out_unlock; | |
5bf9a1ee | 4573 | } |
d696b58c SR |
4574 | |
4575 | entry = ring_buffer_event_data(event); | |
4576 | entry->ip = _THIS_IP_; | |
4577 | ||
4578 | if (nr_pages == 2) { | |
4579 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
4580 | memcpy(&entry->buf, map_page[0] + offset, len); |
4581 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 4582 | } else |
6edb2a8a | 4583 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 4584 | |
d696b58c SR |
4585 | if (entry->buf[cnt - 1] != '\n') { |
4586 | entry->buf[cnt] = '\n'; | |
4587 | entry->buf[cnt + 1] = '\0'; | |
4588 | } else | |
4589 | entry->buf[cnt] = '\0'; | |
4590 | ||
7ffbd48d | 4591 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 4592 | |
d696b58c | 4593 | written = cnt; |
5bf9a1ee | 4594 | |
d696b58c | 4595 | *fpos += written; |
1aa54bca | 4596 | |
d696b58c | 4597 | out_unlock: |
6edb2a8a SR |
4598 | for (i = 0; i < nr_pages; i++){ |
4599 | kunmap_atomic(map_page[i]); | |
4600 | put_page(pages[i]); | |
4601 | } | |
d696b58c | 4602 | out: |
1aa54bca | 4603 | return written; |
5bf9a1ee PP |
4604 | } |
4605 | ||
13f16d20 | 4606 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 4607 | { |
2b6080f2 | 4608 | struct trace_array *tr = m->private; |
5079f326 Z |
4609 | int i; |
4610 | ||
4611 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 4612 | seq_printf(m, |
5079f326 | 4613 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
4614 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
4615 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 4616 | seq_putc(m, '\n'); |
5079f326 | 4617 | |
13f16d20 | 4618 | return 0; |
5079f326 Z |
4619 | } |
4620 | ||
4621 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
4622 | size_t cnt, loff_t *fpos) | |
4623 | { | |
2b6080f2 SR |
4624 | struct seq_file *m = filp->private_data; |
4625 | struct trace_array *tr = m->private; | |
5079f326 Z |
4626 | char buf[64]; |
4627 | const char *clockstr; | |
4628 | int i; | |
4629 | ||
4630 | if (cnt >= sizeof(buf)) | |
4631 | return -EINVAL; | |
4632 | ||
4633 | if (copy_from_user(&buf, ubuf, cnt)) | |
4634 | return -EFAULT; | |
4635 | ||
4636 | buf[cnt] = 0; | |
4637 | ||
4638 | clockstr = strstrip(buf); | |
4639 | ||
4640 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
4641 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
4642 | break; | |
4643 | } | |
4644 | if (i == ARRAY_SIZE(trace_clocks)) | |
4645 | return -EINVAL; | |
4646 | ||
5079f326 Z |
4647 | mutex_lock(&trace_types_lock); |
4648 | ||
2b6080f2 SR |
4649 | tr->clock_id = i; |
4650 | ||
12883efb | 4651 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 4652 | |
60303ed3 DS |
4653 | /* |
4654 | * New clock may not be consistent with the previous clock. | |
4655 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
4656 | */ | |
9457158b | 4657 | tracing_reset_online_cpus(&tr->trace_buffer); |
12883efb SRRH |
4658 | |
4659 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4660 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) | |
4661 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); | |
9457158b | 4662 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 4663 | #endif |
60303ed3 | 4664 | |
5079f326 Z |
4665 | mutex_unlock(&trace_types_lock); |
4666 | ||
4667 | *fpos += cnt; | |
4668 | ||
4669 | return cnt; | |
4670 | } | |
4671 | ||
13f16d20 LZ |
4672 | static int tracing_clock_open(struct inode *inode, struct file *file) |
4673 | { | |
7b85af63 SRRH |
4674 | struct trace_array *tr = inode->i_private; |
4675 | int ret; | |
4676 | ||
13f16d20 LZ |
4677 | if (tracing_disabled) |
4678 | return -ENODEV; | |
2b6080f2 | 4679 | |
7b85af63 SRRH |
4680 | if (trace_array_get(tr)) |
4681 | return -ENODEV; | |
4682 | ||
4683 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
4684 | if (ret < 0) | |
4685 | trace_array_put(tr); | |
4686 | ||
4687 | return ret; | |
13f16d20 LZ |
4688 | } |
4689 | ||
6de58e62 SRRH |
4690 | struct ftrace_buffer_info { |
4691 | struct trace_iterator iter; | |
4692 | void *spare; | |
4693 | unsigned int read; | |
4694 | }; | |
4695 | ||
debdd57f HT |
4696 | #ifdef CONFIG_TRACER_SNAPSHOT |
4697 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
4698 | { | |
6484c71c | 4699 | struct trace_array *tr = inode->i_private; |
debdd57f | 4700 | struct trace_iterator *iter; |
2b6080f2 | 4701 | struct seq_file *m; |
debdd57f HT |
4702 | int ret = 0; |
4703 | ||
ff451961 SRRH |
4704 | if (trace_array_get(tr) < 0) |
4705 | return -ENODEV; | |
4706 | ||
debdd57f | 4707 | if (file->f_mode & FMODE_READ) { |
6484c71c | 4708 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
4709 | if (IS_ERR(iter)) |
4710 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
4711 | } else { |
4712 | /* Writes still need the seq_file to hold the private data */ | |
f77d09a3 | 4713 | ret = -ENOMEM; |
2b6080f2 SR |
4714 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
4715 | if (!m) | |
f77d09a3 | 4716 | goto out; |
2b6080f2 SR |
4717 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
4718 | if (!iter) { | |
4719 | kfree(m); | |
f77d09a3 | 4720 | goto out; |
2b6080f2 | 4721 | } |
f77d09a3 AL |
4722 | ret = 0; |
4723 | ||
ff451961 | 4724 | iter->tr = tr; |
6484c71c ON |
4725 | iter->trace_buffer = &tr->max_buffer; |
4726 | iter->cpu_file = tracing_get_cpu(inode); | |
2b6080f2 SR |
4727 | m->private = iter; |
4728 | file->private_data = m; | |
debdd57f | 4729 | } |
f77d09a3 | 4730 | out: |
ff451961 SRRH |
4731 | if (ret < 0) |
4732 | trace_array_put(tr); | |
4733 | ||
debdd57f HT |
4734 | return ret; |
4735 | } | |
4736 | ||
4737 | static ssize_t | |
4738 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4739 | loff_t *ppos) | |
4740 | { | |
2b6080f2 SR |
4741 | struct seq_file *m = filp->private_data; |
4742 | struct trace_iterator *iter = m->private; | |
4743 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
4744 | unsigned long val; |
4745 | int ret; | |
4746 | ||
4747 | ret = tracing_update_buffers(); | |
4748 | if (ret < 0) | |
4749 | return ret; | |
4750 | ||
4751 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
4752 | if (ret) | |
4753 | return ret; | |
4754 | ||
4755 | mutex_lock(&trace_types_lock); | |
4756 | ||
2b6080f2 | 4757 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
4758 | ret = -EBUSY; |
4759 | goto out; | |
4760 | } | |
4761 | ||
4762 | switch (val) { | |
4763 | case 0: | |
f1affcaa SRRH |
4764 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
4765 | ret = -EINVAL; | |
4766 | break; | |
debdd57f | 4767 | } |
3209cff4 SRRH |
4768 | if (tr->allocated_snapshot) |
4769 | free_snapshot(tr); | |
debdd57f HT |
4770 | break; |
4771 | case 1: | |
f1affcaa SRRH |
4772 | /* Only allow per-cpu swap if the ring buffer supports it */ |
4773 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
4774 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
4775 | ret = -EINVAL; | |
4776 | break; | |
4777 | } | |
4778 | #endif | |
45ad21ca | 4779 | if (!tr->allocated_snapshot) { |
3209cff4 | 4780 | ret = alloc_snapshot(tr); |
debdd57f HT |
4781 | if (ret < 0) |
4782 | break; | |
debdd57f | 4783 | } |
debdd57f HT |
4784 | local_irq_disable(); |
4785 | /* Now, we're going to swap */ | |
f1affcaa | 4786 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 4787 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 4788 | else |
ce9bae55 | 4789 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
4790 | local_irq_enable(); |
4791 | break; | |
4792 | default: | |
45ad21ca | 4793 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
4794 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
4795 | tracing_reset_online_cpus(&tr->max_buffer); | |
4796 | else | |
4797 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
4798 | } | |
debdd57f HT |
4799 | break; |
4800 | } | |
4801 | ||
4802 | if (ret >= 0) { | |
4803 | *ppos += cnt; | |
4804 | ret = cnt; | |
4805 | } | |
4806 | out: | |
4807 | mutex_unlock(&trace_types_lock); | |
4808 | return ret; | |
4809 | } | |
2b6080f2 SR |
4810 | |
4811 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
4812 | { | |
4813 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
4814 | int ret; |
4815 | ||
4816 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
4817 | |
4818 | if (file->f_mode & FMODE_READ) | |
ff451961 | 4819 | return ret; |
2b6080f2 SR |
4820 | |
4821 | /* If write only, the seq_file is just a stub */ | |
4822 | if (m) | |
4823 | kfree(m->private); | |
4824 | kfree(m); | |
4825 | ||
4826 | return 0; | |
4827 | } | |
4828 | ||
6de58e62 SRRH |
4829 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
4830 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4831 | size_t count, loff_t *ppos); | |
4832 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
4833 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
4834 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
4835 | ||
4836 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
4837 | { | |
4838 | struct ftrace_buffer_info *info; | |
4839 | int ret; | |
4840 | ||
4841 | ret = tracing_buffers_open(inode, filp); | |
4842 | if (ret < 0) | |
4843 | return ret; | |
4844 | ||
4845 | info = filp->private_data; | |
4846 | ||
4847 | if (info->iter.trace->use_max_tr) { | |
4848 | tracing_buffers_release(inode, filp); | |
4849 | return -EBUSY; | |
4850 | } | |
4851 | ||
4852 | info->iter.snapshot = true; | |
4853 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
4854 | ||
4855 | return ret; | |
4856 | } | |
4857 | ||
debdd57f HT |
4858 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
4859 | ||
4860 | ||
5e2336a0 | 4861 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
4862 | .open = tracing_open_generic, |
4863 | .read = tracing_max_lat_read, | |
4864 | .write = tracing_max_lat_write, | |
b444786f | 4865 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4866 | }; |
4867 | ||
5e2336a0 | 4868 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
4869 | .open = tracing_open_generic, |
4870 | .read = tracing_set_trace_read, | |
4871 | .write = tracing_set_trace_write, | |
b444786f | 4872 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4873 | }; |
4874 | ||
5e2336a0 | 4875 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 4876 | .open = tracing_open_pipe, |
2a2cc8f7 | 4877 | .poll = tracing_poll_pipe, |
4bf39a94 | 4878 | .read = tracing_read_pipe, |
3c56819b | 4879 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 4880 | .release = tracing_release_pipe, |
b444786f | 4881 | .llseek = no_llseek, |
b3806b43 SR |
4882 | }; |
4883 | ||
5e2336a0 | 4884 | static const struct file_operations tracing_entries_fops = { |
0bc392ee | 4885 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
4886 | .read = tracing_entries_read, |
4887 | .write = tracing_entries_write, | |
b444786f | 4888 | .llseek = generic_file_llseek, |
0bc392ee | 4889 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
4890 | }; |
4891 | ||
f81ab074 | 4892 | static const struct file_operations tracing_total_entries_fops = { |
7b85af63 | 4893 | .open = tracing_open_generic_tr, |
f81ab074 VN |
4894 | .read = tracing_total_entries_read, |
4895 | .llseek = generic_file_llseek, | |
7b85af63 | 4896 | .release = tracing_release_generic_tr, |
f81ab074 VN |
4897 | }; |
4898 | ||
4f271a2a | 4899 | static const struct file_operations tracing_free_buffer_fops = { |
7b85af63 | 4900 | .open = tracing_open_generic_tr, |
4f271a2a VN |
4901 | .write = tracing_free_buffer_write, |
4902 | .release = tracing_free_buffer_release, | |
4903 | }; | |
4904 | ||
5e2336a0 | 4905 | static const struct file_operations tracing_mark_fops = { |
7b85af63 | 4906 | .open = tracing_open_generic_tr, |
5bf9a1ee | 4907 | .write = tracing_mark_write, |
b444786f | 4908 | .llseek = generic_file_llseek, |
7b85af63 | 4909 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
4910 | }; |
4911 | ||
5079f326 | 4912 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
4913 | .open = tracing_clock_open, |
4914 | .read = seq_read, | |
4915 | .llseek = seq_lseek, | |
7b85af63 | 4916 | .release = tracing_single_release_tr, |
5079f326 Z |
4917 | .write = tracing_clock_write, |
4918 | }; | |
4919 | ||
debdd57f HT |
4920 | #ifdef CONFIG_TRACER_SNAPSHOT |
4921 | static const struct file_operations snapshot_fops = { | |
4922 | .open = tracing_snapshot_open, | |
4923 | .read = seq_read, | |
4924 | .write = tracing_snapshot_write, | |
4925 | .llseek = tracing_seek, | |
2b6080f2 | 4926 | .release = tracing_snapshot_release, |
debdd57f | 4927 | }; |
debdd57f | 4928 | |
6de58e62 SRRH |
4929 | static const struct file_operations snapshot_raw_fops = { |
4930 | .open = snapshot_raw_open, | |
4931 | .read = tracing_buffers_read, | |
4932 | .release = tracing_buffers_release, | |
4933 | .splice_read = tracing_buffers_splice_read, | |
4934 | .llseek = no_llseek, | |
2cadf913 SR |
4935 | }; |
4936 | ||
6de58e62 SRRH |
4937 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
4938 | ||
2cadf913 SR |
4939 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
4940 | { | |
46ef2be0 | 4941 | struct trace_array *tr = inode->i_private; |
2cadf913 | 4942 | struct ftrace_buffer_info *info; |
7b85af63 | 4943 | int ret; |
2cadf913 SR |
4944 | |
4945 | if (tracing_disabled) | |
4946 | return -ENODEV; | |
4947 | ||
7b85af63 SRRH |
4948 | if (trace_array_get(tr) < 0) |
4949 | return -ENODEV; | |
4950 | ||
2cadf913 | 4951 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
7b85af63 SRRH |
4952 | if (!info) { |
4953 | trace_array_put(tr); | |
2cadf913 | 4954 | return -ENOMEM; |
7b85af63 | 4955 | } |
2cadf913 | 4956 | |
a695cb58 SRRH |
4957 | mutex_lock(&trace_types_lock); |
4958 | ||
cc60cdc9 | 4959 | info->iter.tr = tr; |
46ef2be0 | 4960 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 4961 | info->iter.trace = tr->current_trace; |
12883efb | 4962 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 4963 | info->spare = NULL; |
2cadf913 | 4964 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 4965 | info->read = (unsigned int)-1; |
2cadf913 SR |
4966 | |
4967 | filp->private_data = info; | |
4968 | ||
a695cb58 SRRH |
4969 | mutex_unlock(&trace_types_lock); |
4970 | ||
7b85af63 SRRH |
4971 | ret = nonseekable_open(inode, filp); |
4972 | if (ret < 0) | |
4973 | trace_array_put(tr); | |
4974 | ||
4975 | return ret; | |
2cadf913 SR |
4976 | } |
4977 | ||
cc60cdc9 SR |
4978 | static unsigned int |
4979 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
4980 | { | |
4981 | struct ftrace_buffer_info *info = filp->private_data; | |
4982 | struct trace_iterator *iter = &info->iter; | |
4983 | ||
4984 | return trace_poll(iter, filp, poll_table); | |
4985 | } | |
4986 | ||
2cadf913 SR |
4987 | static ssize_t |
4988 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4989 | size_t count, loff_t *ppos) | |
4990 | { | |
4991 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 4992 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 4993 | ssize_t ret; |
6de58e62 | 4994 | ssize_t size; |
2cadf913 | 4995 | |
2dc5d12b SR |
4996 | if (!count) |
4997 | return 0; | |
4998 | ||
6de58e62 SRRH |
4999 | mutex_lock(&trace_types_lock); |
5000 | ||
5001 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5002 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
5003 | size = -EBUSY; | |
5004 | goto out_unlock; | |
5005 | } | |
5006 | #endif | |
5007 | ||
ddd538f3 | 5008 | if (!info->spare) |
12883efb SRRH |
5009 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
5010 | iter->cpu_file); | |
6de58e62 | 5011 | size = -ENOMEM; |
ddd538f3 | 5012 | if (!info->spare) |
6de58e62 | 5013 | goto out_unlock; |
ddd538f3 | 5014 | |
2cadf913 SR |
5015 | /* Do we have previous read data to read? */ |
5016 | if (info->read < PAGE_SIZE) | |
5017 | goto read; | |
5018 | ||
b627344f | 5019 | again: |
cc60cdc9 | 5020 | trace_access_lock(iter->cpu_file); |
12883efb | 5021 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
5022 | &info->spare, |
5023 | count, | |
cc60cdc9 SR |
5024 | iter->cpu_file, 0); |
5025 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 5026 | |
b627344f SR |
5027 | if (ret < 0) { |
5028 | if (trace_empty(iter)) { | |
6de58e62 SRRH |
5029 | if ((filp->f_flags & O_NONBLOCK)) { |
5030 | size = -EAGAIN; | |
5031 | goto out_unlock; | |
5032 | } | |
5033 | mutex_unlock(&trace_types_lock); | |
b627344f | 5034 | iter->trace->wait_pipe(iter); |
6de58e62 SRRH |
5035 | mutex_lock(&trace_types_lock); |
5036 | if (signal_pending(current)) { | |
5037 | size = -EINTR; | |
5038 | goto out_unlock; | |
5039 | } | |
b627344f SR |
5040 | goto again; |
5041 | } | |
6de58e62 SRRH |
5042 | size = 0; |
5043 | goto out_unlock; | |
b627344f | 5044 | } |
436fc280 | 5045 | |
436fc280 | 5046 | info->read = 0; |
b627344f | 5047 | read: |
2cadf913 SR |
5048 | size = PAGE_SIZE - info->read; |
5049 | if (size > count) | |
5050 | size = count; | |
5051 | ||
5052 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
6de58e62 SRRH |
5053 | if (ret == size) { |
5054 | size = -EFAULT; | |
5055 | goto out_unlock; | |
5056 | } | |
2dc5d12b SR |
5057 | size -= ret; |
5058 | ||
2cadf913 SR |
5059 | *ppos += size; |
5060 | info->read += size; | |
5061 | ||
6de58e62 SRRH |
5062 | out_unlock: |
5063 | mutex_unlock(&trace_types_lock); | |
5064 | ||
2cadf913 SR |
5065 | return size; |
5066 | } | |
5067 | ||
5068 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
5069 | { | |
5070 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5071 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5072 | |
a695cb58 SRRH |
5073 | mutex_lock(&trace_types_lock); |
5074 | ||
ff451961 | 5075 | __trace_array_put(iter->tr); |
2cadf913 | 5076 | |
ddd538f3 | 5077 | if (info->spare) |
12883efb | 5078 | ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); |
2cadf913 SR |
5079 | kfree(info); |
5080 | ||
a695cb58 SRRH |
5081 | mutex_unlock(&trace_types_lock); |
5082 | ||
2cadf913 SR |
5083 | return 0; |
5084 | } | |
5085 | ||
5086 | struct buffer_ref { | |
5087 | struct ring_buffer *buffer; | |
5088 | void *page; | |
5089 | int ref; | |
5090 | }; | |
5091 | ||
5092 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
5093 | struct pipe_buffer *buf) | |
5094 | { | |
5095 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5096 | ||
5097 | if (--ref->ref) | |
5098 | return; | |
5099 | ||
5100 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5101 | kfree(ref); | |
5102 | buf->private = 0; | |
5103 | } | |
5104 | ||
2cadf913 SR |
5105 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
5106 | struct pipe_buffer *buf) | |
5107 | { | |
5108 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5109 | ||
5110 | ref->ref++; | |
5111 | } | |
5112 | ||
5113 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 5114 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
5115 | .can_merge = 0, |
5116 | .map = generic_pipe_buf_map, | |
5117 | .unmap = generic_pipe_buf_unmap, | |
5118 | .confirm = generic_pipe_buf_confirm, | |
5119 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 5120 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
5121 | .get = buffer_pipe_buf_get, |
5122 | }; | |
5123 | ||
5124 | /* | |
5125 | * Callback from splice_to_pipe(), if we need to release some pages | |
5126 | * at the end of the spd in case we error'ed out in filling the pipe. | |
5127 | */ | |
5128 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
5129 | { | |
5130 | struct buffer_ref *ref = | |
5131 | (struct buffer_ref *)spd->partial[i].private; | |
5132 | ||
5133 | if (--ref->ref) | |
5134 | return; | |
5135 | ||
5136 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5137 | kfree(ref); | |
5138 | spd->partial[i].private = 0; | |
5139 | } | |
5140 | ||
5141 | static ssize_t | |
5142 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5143 | struct pipe_inode_info *pipe, size_t len, | |
5144 | unsigned int flags) | |
5145 | { | |
5146 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5147 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
5148 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
5149 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 5150 | struct splice_pipe_desc spd = { |
35f3d14d JA |
5151 | .pages = pages_def, |
5152 | .partial = partial_def, | |
047fe360 | 5153 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
5154 | .flags = flags, |
5155 | .ops = &buffer_pipe_buf_ops, | |
5156 | .spd_release = buffer_spd_release, | |
5157 | }; | |
5158 | struct buffer_ref *ref; | |
93459c6c | 5159 | int entries, size, i; |
6de58e62 | 5160 | ssize_t ret; |
2cadf913 | 5161 | |
6de58e62 SRRH |
5162 | mutex_lock(&trace_types_lock); |
5163 | ||
5164 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5165 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
5166 | ret = -EBUSY; | |
5167 | goto out; | |
5168 | } | |
5169 | #endif | |
5170 | ||
5171 | if (splice_grow_spd(pipe, &spd)) { | |
5172 | ret = -ENOMEM; | |
5173 | goto out; | |
5174 | } | |
35f3d14d | 5175 | |
93cfb3c9 | 5176 | if (*ppos & (PAGE_SIZE - 1)) { |
35f3d14d JA |
5177 | ret = -EINVAL; |
5178 | goto out; | |
93cfb3c9 LJ |
5179 | } |
5180 | ||
5181 | if (len & (PAGE_SIZE - 1)) { | |
35f3d14d JA |
5182 | if (len < PAGE_SIZE) { |
5183 | ret = -EINVAL; | |
5184 | goto out; | |
5185 | } | |
93cfb3c9 LJ |
5186 | len &= PAGE_MASK; |
5187 | } | |
5188 | ||
cc60cdc9 SR |
5189 | again: |
5190 | trace_access_lock(iter->cpu_file); | |
12883efb | 5191 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 5192 | |
35f3d14d | 5193 | for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
5194 | struct page *page; |
5195 | int r; | |
5196 | ||
5197 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
5198 | if (!ref) | |
5199 | break; | |
5200 | ||
7267fa68 | 5201 | ref->ref = 1; |
12883efb | 5202 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 5203 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
2cadf913 SR |
5204 | if (!ref->page) { |
5205 | kfree(ref); | |
5206 | break; | |
5207 | } | |
5208 | ||
5209 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 5210 | len, iter->cpu_file, 1); |
2cadf913 | 5211 | if (r < 0) { |
7ea59064 | 5212 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
5213 | kfree(ref); |
5214 | break; | |
5215 | } | |
5216 | ||
5217 | /* | |
5218 | * zero out any left over data, this is going to | |
5219 | * user land. | |
5220 | */ | |
5221 | size = ring_buffer_page_len(ref->page); | |
5222 | if (size < PAGE_SIZE) | |
5223 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
5224 | ||
5225 | page = virt_to_page(ref->page); | |
5226 | ||
5227 | spd.pages[i] = page; | |
5228 | spd.partial[i].len = PAGE_SIZE; | |
5229 | spd.partial[i].offset = 0; | |
5230 | spd.partial[i].private = (unsigned long)ref; | |
5231 | spd.nr_pages++; | |
93cfb3c9 | 5232 | *ppos += PAGE_SIZE; |
93459c6c | 5233 | |
12883efb | 5234 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
5235 | } |
5236 | ||
cc60cdc9 | 5237 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
5238 | spd.nr_pages = i; |
5239 | ||
5240 | /* did we read anything? */ | |
5241 | if (!spd.nr_pages) { | |
cc60cdc9 | 5242 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) { |
2cadf913 | 5243 | ret = -EAGAIN; |
cc60cdc9 SR |
5244 | goto out; |
5245 | } | |
6de58e62 | 5246 | mutex_unlock(&trace_types_lock); |
b627344f | 5247 | iter->trace->wait_pipe(iter); |
6de58e62 | 5248 | mutex_lock(&trace_types_lock); |
cc60cdc9 SR |
5249 | if (signal_pending(current)) { |
5250 | ret = -EINTR; | |
5251 | goto out; | |
5252 | } | |
5253 | goto again; | |
2cadf913 SR |
5254 | } |
5255 | ||
5256 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 5257 | splice_shrink_spd(&spd); |
35f3d14d | 5258 | out: |
6de58e62 SRRH |
5259 | mutex_unlock(&trace_types_lock); |
5260 | ||
2cadf913 SR |
5261 | return ret; |
5262 | } | |
5263 | ||
5264 | static const struct file_operations tracing_buffers_fops = { | |
5265 | .open = tracing_buffers_open, | |
5266 | .read = tracing_buffers_read, | |
cc60cdc9 | 5267 | .poll = tracing_buffers_poll, |
2cadf913 SR |
5268 | .release = tracing_buffers_release, |
5269 | .splice_read = tracing_buffers_splice_read, | |
5270 | .llseek = no_llseek, | |
5271 | }; | |
5272 | ||
c8d77183 SR |
5273 | static ssize_t |
5274 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
5275 | size_t count, loff_t *ppos) | |
5276 | { | |
4d3435b8 ON |
5277 | struct inode *inode = file_inode(filp); |
5278 | struct trace_array *tr = inode->i_private; | |
12883efb | 5279 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
4d3435b8 | 5280 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
5281 | struct trace_seq *s; |
5282 | unsigned long cnt; | |
c64e148a VN |
5283 | unsigned long long t; |
5284 | unsigned long usec_rem; | |
c8d77183 | 5285 | |
e4f2d10f | 5286 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 5287 | if (!s) |
a646365c | 5288 | return -ENOMEM; |
c8d77183 SR |
5289 | |
5290 | trace_seq_init(s); | |
5291 | ||
12883efb | 5292 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5293 | trace_seq_printf(s, "entries: %ld\n", cnt); |
5294 | ||
12883efb | 5295 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5296 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
5297 | ||
12883efb | 5298 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5299 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
5300 | ||
12883efb | 5301 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
5302 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
5303 | ||
58e8eedf | 5304 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 5305 | /* local or global for trace_clock */ |
12883efb | 5306 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
5307 | usec_rem = do_div(t, USEC_PER_SEC); |
5308 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
5309 | t, usec_rem); | |
5310 | ||
12883efb | 5311 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
5312 | usec_rem = do_div(t, USEC_PER_SEC); |
5313 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
5314 | } else { | |
5315 | /* counter or tsc mode for trace_clock */ | |
5316 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 5317 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 5318 | |
11043d8b | 5319 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 5320 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 5321 | } |
c64e148a | 5322 | |
12883efb | 5323 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
5324 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
5325 | ||
12883efb | 5326 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
5327 | trace_seq_printf(s, "read events: %ld\n", cnt); |
5328 | ||
c8d77183 SR |
5329 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
5330 | ||
5331 | kfree(s); | |
5332 | ||
5333 | return count; | |
5334 | } | |
5335 | ||
5336 | static const struct file_operations tracing_stats_fops = { | |
4d3435b8 | 5337 | .open = tracing_open_generic_tr, |
c8d77183 | 5338 | .read = tracing_stats_read, |
b444786f | 5339 | .llseek = generic_file_llseek, |
4d3435b8 | 5340 | .release = tracing_release_generic_tr, |
c8d77183 SR |
5341 | }; |
5342 | ||
bc0c38d1 SR |
5343 | #ifdef CONFIG_DYNAMIC_FTRACE |
5344 | ||
b807c3d0 SR |
5345 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
5346 | { | |
5347 | return 0; | |
5348 | } | |
5349 | ||
bc0c38d1 | 5350 | static ssize_t |
b807c3d0 | 5351 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
5352 | size_t cnt, loff_t *ppos) |
5353 | { | |
a26a2a27 SR |
5354 | static char ftrace_dyn_info_buffer[1024]; |
5355 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 5356 | unsigned long *p = filp->private_data; |
b807c3d0 | 5357 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 5358 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
5359 | int r; |
5360 | ||
b807c3d0 SR |
5361 | mutex_lock(&dyn_info_mutex); |
5362 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 5363 | |
a26a2a27 | 5364 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
5365 | buf[r++] = '\n'; |
5366 | ||
5367 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5368 | ||
5369 | mutex_unlock(&dyn_info_mutex); | |
5370 | ||
5371 | return r; | |
bc0c38d1 SR |
5372 | } |
5373 | ||
5e2336a0 | 5374 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 5375 | .open = tracing_open_generic, |
b807c3d0 | 5376 | .read = tracing_read_dyn_info, |
b444786f | 5377 | .llseek = generic_file_llseek, |
bc0c38d1 | 5378 | }; |
77fd5c15 | 5379 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 5380 | |
77fd5c15 SRRH |
5381 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
5382 | static void | |
5383 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
5384 | { | |
5385 | tracing_snapshot(); | |
5386 | } | |
bc0c38d1 | 5387 | |
77fd5c15 SRRH |
5388 | static void |
5389 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
bc0c38d1 | 5390 | { |
77fd5c15 SRRH |
5391 | unsigned long *count = (long *)data; |
5392 | ||
5393 | if (!*count) | |
5394 | return; | |
bc0c38d1 | 5395 | |
77fd5c15 SRRH |
5396 | if (*count != -1) |
5397 | (*count)--; | |
5398 | ||
5399 | tracing_snapshot(); | |
5400 | } | |
5401 | ||
5402 | static int | |
5403 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
5404 | struct ftrace_probe_ops *ops, void *data) | |
5405 | { | |
5406 | long count = (long)data; | |
5407 | ||
5408 | seq_printf(m, "%ps:", (void *)ip); | |
5409 | ||
5410 | seq_printf(m, "snapshot"); | |
5411 | ||
5412 | if (count == -1) | |
5413 | seq_printf(m, ":unlimited\n"); | |
5414 | else | |
5415 | seq_printf(m, ":count=%ld\n", count); | |
5416 | ||
5417 | return 0; | |
5418 | } | |
5419 | ||
5420 | static struct ftrace_probe_ops snapshot_probe_ops = { | |
5421 | .func = ftrace_snapshot, | |
5422 | .print = ftrace_snapshot_print, | |
5423 | }; | |
5424 | ||
5425 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
5426 | .func = ftrace_count_snapshot, | |
5427 | .print = ftrace_snapshot_print, | |
5428 | }; | |
5429 | ||
5430 | static int | |
5431 | ftrace_trace_snapshot_callback(struct ftrace_hash *hash, | |
5432 | char *glob, char *cmd, char *param, int enable) | |
5433 | { | |
5434 | struct ftrace_probe_ops *ops; | |
5435 | void *count = (void *)-1; | |
5436 | char *number; | |
5437 | int ret; | |
5438 | ||
5439 | /* hash funcs only work with set_ftrace_filter */ | |
5440 | if (!enable) | |
5441 | return -EINVAL; | |
5442 | ||
5443 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
5444 | ||
5445 | if (glob[0] == '!') { | |
5446 | unregister_ftrace_function_probe_func(glob+1, ops); | |
5447 | return 0; | |
5448 | } | |
5449 | ||
5450 | if (!param) | |
5451 | goto out_reg; | |
5452 | ||
5453 | number = strsep(¶m, ":"); | |
5454 | ||
5455 | if (!strlen(number)) | |
5456 | goto out_reg; | |
5457 | ||
5458 | /* | |
5459 | * We use the callback data field (which is a pointer) | |
5460 | * as our counter. | |
5461 | */ | |
5462 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
5463 | if (ret) | |
5464 | return ret; | |
5465 | ||
5466 | out_reg: | |
5467 | ret = register_ftrace_function_probe(glob, ops, count); | |
5468 | ||
5469 | if (ret >= 0) | |
5470 | alloc_snapshot(&global_trace); | |
5471 | ||
5472 | return ret < 0 ? ret : 0; | |
5473 | } | |
5474 | ||
5475 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
5476 | .name = "snapshot", | |
5477 | .func = ftrace_trace_snapshot_callback, | |
5478 | }; | |
5479 | ||
5480 | static int register_snapshot_cmd(void) | |
5481 | { | |
5482 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
5483 | } | |
5484 | #else | |
5485 | static inline int register_snapshot_cmd(void) { return 0; } | |
5486 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ | |
bc0c38d1 | 5487 | |
2b6080f2 | 5488 | struct dentry *tracing_init_dentry_tr(struct trace_array *tr) |
bc0c38d1 | 5489 | { |
2b6080f2 SR |
5490 | if (tr->dir) |
5491 | return tr->dir; | |
bc0c38d1 | 5492 | |
3e1f60b8 FW |
5493 | if (!debugfs_initialized()) |
5494 | return NULL; | |
5495 | ||
2b6080f2 SR |
5496 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) |
5497 | tr->dir = debugfs_create_dir("tracing", NULL); | |
bc0c38d1 | 5498 | |
687c878a J |
5499 | if (!tr->dir) |
5500 | pr_warn_once("Could not create debugfs directory 'tracing'\n"); | |
bc0c38d1 | 5501 | |
2b6080f2 | 5502 | return tr->dir; |
bc0c38d1 SR |
5503 | } |
5504 | ||
2b6080f2 SR |
5505 | struct dentry *tracing_init_dentry(void) |
5506 | { | |
5507 | return tracing_init_dentry_tr(&global_trace); | |
5508 | } | |
b04cc6b1 | 5509 | |
2b6080f2 | 5510 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 5511 | { |
b04cc6b1 FW |
5512 | struct dentry *d_tracer; |
5513 | ||
2b6080f2 SR |
5514 | if (tr->percpu_dir) |
5515 | return tr->percpu_dir; | |
b04cc6b1 | 5516 | |
2b6080f2 | 5517 | d_tracer = tracing_init_dentry_tr(tr); |
b04cc6b1 FW |
5518 | if (!d_tracer) |
5519 | return NULL; | |
5520 | ||
2b6080f2 | 5521 | tr->percpu_dir = debugfs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 5522 | |
2b6080f2 SR |
5523 | WARN_ONCE(!tr->percpu_dir, |
5524 | "Could not create debugfs directory 'per_cpu/%d'\n", cpu); | |
b04cc6b1 | 5525 | |
2b6080f2 | 5526 | return tr->percpu_dir; |
b04cc6b1 FW |
5527 | } |
5528 | ||
649e9c70 ON |
5529 | static struct dentry * |
5530 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
5531 | void *data, long cpu, const struct file_operations *fops) | |
5532 | { | |
5533 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
5534 | ||
5535 | if (ret) /* See tracing_get_cpu() */ | |
5536 | ret->d_inode->i_cdev = (void *)(cpu + 1); | |
5537 | return ret; | |
5538 | } | |
5539 | ||
2b6080f2 SR |
5540 | static void |
5541 | tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) | |
b04cc6b1 | 5542 | { |
2b6080f2 | 5543 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 5544 | struct dentry *d_cpu; |
dd49a38c | 5545 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 5546 | |
0a3d7ce7 NK |
5547 | if (!d_percpu) |
5548 | return; | |
5549 | ||
dd49a38c | 5550 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
5551 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
5552 | if (!d_cpu) { | |
5553 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
5554 | return; | |
5555 | } | |
b04cc6b1 | 5556 | |
8656e7a2 | 5557 | /* per cpu trace_pipe */ |
649e9c70 | 5558 | trace_create_cpu_file("trace_pipe", 0444, d_cpu, |
15544209 | 5559 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
5560 | |
5561 | /* per cpu trace */ | |
649e9c70 | 5562 | trace_create_cpu_file("trace", 0644, d_cpu, |
6484c71c | 5563 | tr, cpu, &tracing_fops); |
7f96f93f | 5564 | |
649e9c70 | 5565 | trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, |
46ef2be0 | 5566 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 5567 | |
649e9c70 | 5568 | trace_create_cpu_file("stats", 0444, d_cpu, |
4d3435b8 | 5569 | tr, cpu, &tracing_stats_fops); |
438ced17 | 5570 | |
649e9c70 | 5571 | trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, |
0bc392ee | 5572 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
5573 | |
5574 | #ifdef CONFIG_TRACER_SNAPSHOT | |
649e9c70 | 5575 | trace_create_cpu_file("snapshot", 0644, d_cpu, |
6484c71c | 5576 | tr, cpu, &snapshot_fops); |
6de58e62 | 5577 | |
649e9c70 | 5578 | trace_create_cpu_file("snapshot_raw", 0444, d_cpu, |
46ef2be0 | 5579 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 5580 | #endif |
b04cc6b1 FW |
5581 | } |
5582 | ||
60a11774 SR |
5583 | #ifdef CONFIG_FTRACE_SELFTEST |
5584 | /* Let selftest have access to static functions in this file */ | |
5585 | #include "trace_selftest.c" | |
5586 | #endif | |
5587 | ||
577b785f SR |
5588 | struct trace_option_dentry { |
5589 | struct tracer_opt *opt; | |
5590 | struct tracer_flags *flags; | |
2b6080f2 | 5591 | struct trace_array *tr; |
577b785f SR |
5592 | struct dentry *entry; |
5593 | }; | |
5594 | ||
5595 | static ssize_t | |
5596 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5597 | loff_t *ppos) | |
5598 | { | |
5599 | struct trace_option_dentry *topt = filp->private_data; | |
5600 | char *buf; | |
5601 | ||
5602 | if (topt->flags->val & topt->opt->bit) | |
5603 | buf = "1\n"; | |
5604 | else | |
5605 | buf = "0\n"; | |
5606 | ||
5607 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5608 | } | |
5609 | ||
5610 | static ssize_t | |
5611 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5612 | loff_t *ppos) | |
5613 | { | |
5614 | struct trace_option_dentry *topt = filp->private_data; | |
5615 | unsigned long val; | |
577b785f SR |
5616 | int ret; |
5617 | ||
22fe9b54 PH |
5618 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5619 | if (ret) | |
577b785f SR |
5620 | return ret; |
5621 | ||
8d18eaaf LZ |
5622 | if (val != 0 && val != 1) |
5623 | return -EINVAL; | |
577b785f | 5624 | |
8d18eaaf | 5625 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 5626 | mutex_lock(&trace_types_lock); |
2b6080f2 | 5627 | ret = __set_tracer_option(topt->tr->current_trace, topt->flags, |
c757bea9 | 5628 | topt->opt, !val); |
577b785f SR |
5629 | mutex_unlock(&trace_types_lock); |
5630 | if (ret) | |
5631 | return ret; | |
577b785f SR |
5632 | } |
5633 | ||
5634 | *ppos += cnt; | |
5635 | ||
5636 | return cnt; | |
5637 | } | |
5638 | ||
5639 | ||
5640 | static const struct file_operations trace_options_fops = { | |
5641 | .open = tracing_open_generic, | |
5642 | .read = trace_options_read, | |
5643 | .write = trace_options_write, | |
b444786f | 5644 | .llseek = generic_file_llseek, |
577b785f SR |
5645 | }; |
5646 | ||
a8259075 SR |
5647 | static ssize_t |
5648 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5649 | loff_t *ppos) | |
5650 | { | |
5651 | long index = (long)filp->private_data; | |
5652 | char *buf; | |
5653 | ||
5654 | if (trace_flags & (1 << index)) | |
5655 | buf = "1\n"; | |
5656 | else | |
5657 | buf = "0\n"; | |
5658 | ||
5659 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5660 | } | |
5661 | ||
5662 | static ssize_t | |
5663 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5664 | loff_t *ppos) | |
5665 | { | |
2b6080f2 | 5666 | struct trace_array *tr = &global_trace; |
a8259075 | 5667 | long index = (long)filp->private_data; |
a8259075 SR |
5668 | unsigned long val; |
5669 | int ret; | |
5670 | ||
22fe9b54 PH |
5671 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5672 | if (ret) | |
a8259075 SR |
5673 | return ret; |
5674 | ||
f2d84b65 | 5675 | if (val != 0 && val != 1) |
a8259075 | 5676 | return -EINVAL; |
69d34da2 SRRH |
5677 | |
5678 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 5679 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 5680 | mutex_unlock(&trace_types_lock); |
a8259075 | 5681 | |
613f04a0 SRRH |
5682 | if (ret < 0) |
5683 | return ret; | |
5684 | ||
a8259075 SR |
5685 | *ppos += cnt; |
5686 | ||
5687 | return cnt; | |
5688 | } | |
5689 | ||
a8259075 SR |
5690 | static const struct file_operations trace_options_core_fops = { |
5691 | .open = tracing_open_generic, | |
5692 | .read = trace_options_core_read, | |
5693 | .write = trace_options_core_write, | |
b444786f | 5694 | .llseek = generic_file_llseek, |
a8259075 SR |
5695 | }; |
5696 | ||
5452af66 | 5697 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 5698 | umode_t mode, |
5452af66 FW |
5699 | struct dentry *parent, |
5700 | void *data, | |
5701 | const struct file_operations *fops) | |
5702 | { | |
5703 | struct dentry *ret; | |
5704 | ||
5705 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
5706 | if (!ret) | |
5707 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
5708 | ||
5709 | return ret; | |
5710 | } | |
5711 | ||
5712 | ||
2b6080f2 | 5713 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
5714 | { |
5715 | struct dentry *d_tracer; | |
a8259075 | 5716 | |
2b6080f2 SR |
5717 | if (tr->options) |
5718 | return tr->options; | |
a8259075 | 5719 | |
2b6080f2 | 5720 | d_tracer = tracing_init_dentry_tr(tr); |
a8259075 SR |
5721 | if (!d_tracer) |
5722 | return NULL; | |
5723 | ||
2b6080f2 SR |
5724 | tr->options = debugfs_create_dir("options", d_tracer); |
5725 | if (!tr->options) { | |
a8259075 SR |
5726 | pr_warning("Could not create debugfs directory 'options'\n"); |
5727 | return NULL; | |
5728 | } | |
5729 | ||
2b6080f2 | 5730 | return tr->options; |
a8259075 SR |
5731 | } |
5732 | ||
577b785f | 5733 | static void |
2b6080f2 SR |
5734 | create_trace_option_file(struct trace_array *tr, |
5735 | struct trace_option_dentry *topt, | |
577b785f SR |
5736 | struct tracer_flags *flags, |
5737 | struct tracer_opt *opt) | |
5738 | { | |
5739 | struct dentry *t_options; | |
577b785f | 5740 | |
2b6080f2 | 5741 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
5742 | if (!t_options) |
5743 | return; | |
5744 | ||
5745 | topt->flags = flags; | |
5746 | topt->opt = opt; | |
2b6080f2 | 5747 | topt->tr = tr; |
577b785f | 5748 | |
5452af66 | 5749 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
5750 | &trace_options_fops); |
5751 | ||
577b785f SR |
5752 | } |
5753 | ||
5754 | static struct trace_option_dentry * | |
2b6080f2 | 5755 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
5756 | { |
5757 | struct trace_option_dentry *topts; | |
5758 | struct tracer_flags *flags; | |
5759 | struct tracer_opt *opts; | |
5760 | int cnt; | |
5761 | ||
5762 | if (!tracer) | |
5763 | return NULL; | |
5764 | ||
5765 | flags = tracer->flags; | |
5766 | ||
5767 | if (!flags || !flags->opts) | |
5768 | return NULL; | |
5769 | ||
5770 | opts = flags->opts; | |
5771 | ||
5772 | for (cnt = 0; opts[cnt].name; cnt++) | |
5773 | ; | |
5774 | ||
0cfe8245 | 5775 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
5776 | if (!topts) |
5777 | return NULL; | |
5778 | ||
5779 | for (cnt = 0; opts[cnt].name; cnt++) | |
2b6080f2 | 5780 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f SR |
5781 | &opts[cnt]); |
5782 | ||
5783 | return topts; | |
5784 | } | |
5785 | ||
5786 | static void | |
5787 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
5788 | { | |
5789 | int cnt; | |
5790 | ||
5791 | if (!topts) | |
5792 | return; | |
5793 | ||
5794 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
5795 | if (topts[cnt].entry) | |
5796 | debugfs_remove(topts[cnt].entry); | |
5797 | } | |
5798 | ||
5799 | kfree(topts); | |
5800 | } | |
5801 | ||
a8259075 | 5802 | static struct dentry * |
2b6080f2 SR |
5803 | create_trace_option_core_file(struct trace_array *tr, |
5804 | const char *option, long index) | |
a8259075 SR |
5805 | { |
5806 | struct dentry *t_options; | |
a8259075 | 5807 | |
2b6080f2 | 5808 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5809 | if (!t_options) |
5810 | return NULL; | |
5811 | ||
5452af66 | 5812 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 5813 | &trace_options_core_fops); |
a8259075 SR |
5814 | } |
5815 | ||
2b6080f2 | 5816 | static __init void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
5817 | { |
5818 | struct dentry *t_options; | |
a8259075 SR |
5819 | int i; |
5820 | ||
2b6080f2 | 5821 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5822 | if (!t_options) |
5823 | return; | |
5824 | ||
5452af66 | 5825 | for (i = 0; trace_options[i]; i++) |
2b6080f2 | 5826 | create_trace_option_core_file(tr, trace_options[i], i); |
a8259075 SR |
5827 | } |
5828 | ||
499e5470 SR |
5829 | static ssize_t |
5830 | rb_simple_read(struct file *filp, char __user *ubuf, | |
5831 | size_t cnt, loff_t *ppos) | |
5832 | { | |
348f0fc2 | 5833 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
5834 | char buf[64]; |
5835 | int r; | |
5836 | ||
10246fa3 | 5837 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
5838 | r = sprintf(buf, "%d\n", r); |
5839 | ||
5840 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5841 | } | |
5842 | ||
5843 | static ssize_t | |
5844 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
5845 | size_t cnt, loff_t *ppos) | |
5846 | { | |
348f0fc2 | 5847 | struct trace_array *tr = filp->private_data; |
12883efb | 5848 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
5849 | unsigned long val; |
5850 | int ret; | |
5851 | ||
5852 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5853 | if (ret) | |
5854 | return ret; | |
5855 | ||
5856 | if (buffer) { | |
2df8f8a6 SR |
5857 | mutex_lock(&trace_types_lock); |
5858 | if (val) { | |
10246fa3 | 5859 | tracer_tracing_on(tr); |
2b6080f2 SR |
5860 | if (tr->current_trace->start) |
5861 | tr->current_trace->start(tr); | |
2df8f8a6 | 5862 | } else { |
10246fa3 | 5863 | tracer_tracing_off(tr); |
2b6080f2 SR |
5864 | if (tr->current_trace->stop) |
5865 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
5866 | } |
5867 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
5868 | } |
5869 | ||
5870 | (*ppos)++; | |
5871 | ||
5872 | return cnt; | |
5873 | } | |
5874 | ||
5875 | static const struct file_operations rb_simple_fops = { | |
7b85af63 | 5876 | .open = tracing_open_generic_tr, |
499e5470 SR |
5877 | .read = rb_simple_read, |
5878 | .write = rb_simple_write, | |
7b85af63 | 5879 | .release = tracing_release_generic_tr, |
499e5470 SR |
5880 | .llseek = default_llseek, |
5881 | }; | |
5882 | ||
277ba044 SR |
5883 | struct dentry *trace_instance_dir; |
5884 | ||
5885 | static void | |
5886 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer); | |
5887 | ||
55034cd6 SRRH |
5888 | static int |
5889 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
5890 | { |
5891 | enum ring_buffer_flags rb_flags; | |
737223fb SRRH |
5892 | |
5893 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; | |
5894 | ||
55034cd6 SRRH |
5895 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
5896 | if (!buf->buffer) | |
5897 | return -ENOMEM; | |
737223fb | 5898 | |
55034cd6 SRRH |
5899 | buf->data = alloc_percpu(struct trace_array_cpu); |
5900 | if (!buf->data) { | |
5901 | ring_buffer_free(buf->buffer); | |
5902 | return -ENOMEM; | |
5903 | } | |
737223fb | 5904 | |
737223fb SRRH |
5905 | /* Allocate the first page for all buffers */ |
5906 | set_buffer_entries(&tr->trace_buffer, | |
5907 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
5908 | ||
55034cd6 SRRH |
5909 | return 0; |
5910 | } | |
737223fb | 5911 | |
55034cd6 SRRH |
5912 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
5913 | { | |
5914 | int ret; | |
737223fb | 5915 | |
55034cd6 SRRH |
5916 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
5917 | if (ret) | |
5918 | return ret; | |
737223fb | 5919 | |
55034cd6 SRRH |
5920 | #ifdef CONFIG_TRACER_MAX_TRACE |
5921 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
5922 | allocate_snapshot ? size : 1); | |
5923 | if (WARN_ON(ret)) { | |
737223fb | 5924 | ring_buffer_free(tr->trace_buffer.buffer); |
55034cd6 SRRH |
5925 | free_percpu(tr->trace_buffer.data); |
5926 | return -ENOMEM; | |
5927 | } | |
5928 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 5929 | |
55034cd6 SRRH |
5930 | /* |
5931 | * Only the top level trace array gets its snapshot allocated | |
5932 | * from the kernel command line. | |
5933 | */ | |
5934 | allocate_snapshot = false; | |
737223fb | 5935 | #endif |
55034cd6 | 5936 | return 0; |
737223fb SRRH |
5937 | } |
5938 | ||
5939 | static int new_instance_create(const char *name) | |
5940 | { | |
277ba044 SR |
5941 | struct trace_array *tr; |
5942 | int ret; | |
277ba044 SR |
5943 | |
5944 | mutex_lock(&trace_types_lock); | |
5945 | ||
5946 | ret = -EEXIST; | |
5947 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
5948 | if (tr->name && strcmp(tr->name, name) == 0) | |
5949 | goto out_unlock; | |
5950 | } | |
5951 | ||
5952 | ret = -ENOMEM; | |
5953 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
5954 | if (!tr) | |
5955 | goto out_unlock; | |
5956 | ||
5957 | tr->name = kstrdup(name, GFP_KERNEL); | |
5958 | if (!tr->name) | |
5959 | goto out_free_tr; | |
5960 | ||
ccfe9e42 AL |
5961 | if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) |
5962 | goto out_free_tr; | |
5963 | ||
5964 | cpumask_copy(tr->tracing_cpumask, cpu_all_mask); | |
5965 | ||
277ba044 SR |
5966 | raw_spin_lock_init(&tr->start_lock); |
5967 | ||
5968 | tr->current_trace = &nop_trace; | |
5969 | ||
5970 | INIT_LIST_HEAD(&tr->systems); | |
5971 | INIT_LIST_HEAD(&tr->events); | |
5972 | ||
737223fb | 5973 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
5974 | goto out_free_tr; |
5975 | ||
277ba044 SR |
5976 | tr->dir = debugfs_create_dir(name, trace_instance_dir); |
5977 | if (!tr->dir) | |
5978 | goto out_free_tr; | |
5979 | ||
5980 | ret = event_trace_add_tracer(tr->dir, tr); | |
609e85a7 AL |
5981 | if (ret) { |
5982 | debugfs_remove_recursive(tr->dir); | |
277ba044 | 5983 | goto out_free_tr; |
609e85a7 | 5984 | } |
277ba044 SR |
5985 | |
5986 | init_tracer_debugfs(tr, tr->dir); | |
5987 | ||
5988 | list_add(&tr->list, &ftrace_trace_arrays); | |
5989 | ||
5990 | mutex_unlock(&trace_types_lock); | |
5991 | ||
5992 | return 0; | |
5993 | ||
5994 | out_free_tr: | |
12883efb SRRH |
5995 | if (tr->trace_buffer.buffer) |
5996 | ring_buffer_free(tr->trace_buffer.buffer); | |
ccfe9e42 | 5997 | free_cpumask_var(tr->tracing_cpumask); |
277ba044 SR |
5998 | kfree(tr->name); |
5999 | kfree(tr); | |
6000 | ||
6001 | out_unlock: | |
6002 | mutex_unlock(&trace_types_lock); | |
6003 | ||
6004 | return ret; | |
6005 | ||
6006 | } | |
6007 | ||
0c8916c3 SR |
6008 | static int instance_delete(const char *name) |
6009 | { | |
6010 | struct trace_array *tr; | |
6011 | int found = 0; | |
6012 | int ret; | |
6013 | ||
6014 | mutex_lock(&trace_types_lock); | |
6015 | ||
6016 | ret = -ENODEV; | |
6017 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6018 | if (tr->name && strcmp(tr->name, name) == 0) { | |
6019 | found = 1; | |
6020 | break; | |
6021 | } | |
6022 | } | |
6023 | if (!found) | |
6024 | goto out_unlock; | |
6025 | ||
a695cb58 SRRH |
6026 | ret = -EBUSY; |
6027 | if (tr->ref) | |
6028 | goto out_unlock; | |
6029 | ||
0c8916c3 SR |
6030 | list_del(&tr->list); |
6031 | ||
6032 | event_trace_del_tracer(tr); | |
6033 | debugfs_remove_recursive(tr->dir); | |
12883efb SRRH |
6034 | free_percpu(tr->trace_buffer.data); |
6035 | ring_buffer_free(tr->trace_buffer.buffer); | |
0c8916c3 SR |
6036 | |
6037 | kfree(tr->name); | |
6038 | kfree(tr); | |
6039 | ||
6040 | ret = 0; | |
6041 | ||
6042 | out_unlock: | |
6043 | mutex_unlock(&trace_types_lock); | |
6044 | ||
6045 | return ret; | |
6046 | } | |
6047 | ||
277ba044 SR |
6048 | static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t mode) |
6049 | { | |
6050 | struct dentry *parent; | |
6051 | int ret; | |
6052 | ||
6053 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
6054 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
6055 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
6056 | return -ENOENT; | |
6057 | ||
6058 | /* | |
6059 | * The inode mutex is locked, but debugfs_create_dir() will also | |
6060 | * take the mutex. As the instances directory can not be destroyed | |
6061 | * or changed in any other way, it is safe to unlock it, and | |
6062 | * let the dentry try. If two users try to make the same dir at | |
6063 | * the same time, then the new_instance_create() will determine the | |
6064 | * winner. | |
6065 | */ | |
6066 | mutex_unlock(&inode->i_mutex); | |
6067 | ||
6068 | ret = new_instance_create(dentry->d_iname); | |
6069 | ||
6070 | mutex_lock(&inode->i_mutex); | |
6071 | ||
6072 | return ret; | |
6073 | } | |
6074 | ||
0c8916c3 SR |
6075 | static int instance_rmdir(struct inode *inode, struct dentry *dentry) |
6076 | { | |
6077 | struct dentry *parent; | |
6078 | int ret; | |
6079 | ||
6080 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
6081 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
6082 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
6083 | return -ENOENT; | |
6084 | ||
6085 | /* The caller did a dget() on dentry */ | |
6086 | mutex_unlock(&dentry->d_inode->i_mutex); | |
6087 | ||
6088 | /* | |
6089 | * The inode mutex is locked, but debugfs_create_dir() will also | |
6090 | * take the mutex. As the instances directory can not be destroyed | |
6091 | * or changed in any other way, it is safe to unlock it, and | |
6092 | * let the dentry try. If two users try to make the same dir at | |
6093 | * the same time, then the instance_delete() will determine the | |
6094 | * winner. | |
6095 | */ | |
6096 | mutex_unlock(&inode->i_mutex); | |
6097 | ||
6098 | ret = instance_delete(dentry->d_iname); | |
6099 | ||
6100 | mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); | |
6101 | mutex_lock(&dentry->d_inode->i_mutex); | |
6102 | ||
6103 | return ret; | |
6104 | } | |
6105 | ||
277ba044 SR |
6106 | static const struct inode_operations instance_dir_inode_operations = { |
6107 | .lookup = simple_lookup, | |
6108 | .mkdir = instance_mkdir, | |
0c8916c3 | 6109 | .rmdir = instance_rmdir, |
277ba044 SR |
6110 | }; |
6111 | ||
6112 | static __init void create_trace_instances(struct dentry *d_tracer) | |
6113 | { | |
6114 | trace_instance_dir = debugfs_create_dir("instances", d_tracer); | |
6115 | if (WARN_ON(!trace_instance_dir)) | |
6116 | return; | |
6117 | ||
6118 | /* Hijack the dir inode operations, to allow mkdir */ | |
6119 | trace_instance_dir->d_inode->i_op = &instance_dir_inode_operations; | |
6120 | } | |
6121 | ||
2b6080f2 SR |
6122 | static void |
6123 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) | |
6124 | { | |
121aaee7 | 6125 | int cpu; |
2b6080f2 | 6126 | |
ccfe9e42 AL |
6127 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
6128 | tr, &tracing_cpumask_fops); | |
6129 | ||
2b6080f2 SR |
6130 | trace_create_file("trace_options", 0644, d_tracer, |
6131 | tr, &tracing_iter_fops); | |
6132 | ||
6133 | trace_create_file("trace", 0644, d_tracer, | |
6484c71c | 6134 | tr, &tracing_fops); |
2b6080f2 SR |
6135 | |
6136 | trace_create_file("trace_pipe", 0444, d_tracer, | |
15544209 | 6137 | tr, &tracing_pipe_fops); |
2b6080f2 SR |
6138 | |
6139 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
0bc392ee | 6140 | tr, &tracing_entries_fops); |
2b6080f2 SR |
6141 | |
6142 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
6143 | tr, &tracing_total_entries_fops); | |
6144 | ||
238ae93d | 6145 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
6146 | tr, &tracing_free_buffer_fops); |
6147 | ||
6148 | trace_create_file("trace_marker", 0220, d_tracer, | |
6149 | tr, &tracing_mark_fops); | |
6150 | ||
6151 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
6152 | &trace_clock_fops); | |
6153 | ||
6154 | trace_create_file("tracing_on", 0644, d_tracer, | |
6484c71c | 6155 | tr, &rb_simple_fops); |
ce9bae55 SRRH |
6156 | |
6157 | #ifdef CONFIG_TRACER_SNAPSHOT | |
6158 | trace_create_file("snapshot", 0644, d_tracer, | |
6484c71c | 6159 | tr, &snapshot_fops); |
ce9bae55 | 6160 | #endif |
121aaee7 SRRH |
6161 | |
6162 | for_each_tracing_cpu(cpu) | |
6163 | tracing_init_debugfs_percpu(tr, cpu); | |
6164 | ||
2b6080f2 SR |
6165 | } |
6166 | ||
b5ad384e | 6167 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
6168 | { |
6169 | struct dentry *d_tracer; | |
bc0c38d1 | 6170 | |
7e53bd42 LJ |
6171 | trace_access_lock_init(); |
6172 | ||
bc0c38d1 | 6173 | d_tracer = tracing_init_dentry(); |
ed6f1c99 NK |
6174 | if (!d_tracer) |
6175 | return 0; | |
bc0c38d1 | 6176 | |
2b6080f2 | 6177 | init_tracer_debugfs(&global_trace, d_tracer); |
bc0c38d1 | 6178 | |
5452af66 FW |
6179 | trace_create_file("available_tracers", 0444, d_tracer, |
6180 | &global_trace, &show_traces_fops); | |
6181 | ||
339ae5d3 | 6182 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
6183 | &global_trace, &set_tracer_fops); |
6184 | ||
5d4a9dba | 6185 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
6186 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
6187 | &tracing_max_latency, &tracing_max_lat_fops); | |
0e950173 | 6188 | #endif |
5452af66 FW |
6189 | |
6190 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
6191 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 6192 | |
339ae5d3 | 6193 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
6194 | NULL, &tracing_readme_fops); |
6195 | ||
69abe6a5 AP |
6196 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
6197 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 6198 | |
bc0c38d1 | 6199 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
6200 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
6201 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 6202 | #endif |
b04cc6b1 | 6203 | |
277ba044 | 6204 | create_trace_instances(d_tracer); |
5452af66 | 6205 | |
2b6080f2 | 6206 | create_trace_options_dir(&global_trace); |
b04cc6b1 | 6207 | |
b5ad384e | 6208 | return 0; |
bc0c38d1 SR |
6209 | } |
6210 | ||
3f5a54e3 SR |
6211 | static int trace_panic_handler(struct notifier_block *this, |
6212 | unsigned long event, void *unused) | |
6213 | { | |
944ac425 | 6214 | if (ftrace_dump_on_oops) |
cecbca96 | 6215 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6216 | return NOTIFY_OK; |
6217 | } | |
6218 | ||
6219 | static struct notifier_block trace_panic_notifier = { | |
6220 | .notifier_call = trace_panic_handler, | |
6221 | .next = NULL, | |
6222 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
6223 | }; | |
6224 | ||
6225 | static int trace_die_handler(struct notifier_block *self, | |
6226 | unsigned long val, | |
6227 | void *data) | |
6228 | { | |
6229 | switch (val) { | |
6230 | case DIE_OOPS: | |
944ac425 | 6231 | if (ftrace_dump_on_oops) |
cecbca96 | 6232 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6233 | break; |
6234 | default: | |
6235 | break; | |
6236 | } | |
6237 | return NOTIFY_OK; | |
6238 | } | |
6239 | ||
6240 | static struct notifier_block trace_die_notifier = { | |
6241 | .notifier_call = trace_die_handler, | |
6242 | .priority = 200 | |
6243 | }; | |
6244 | ||
6245 | /* | |
6246 | * printk is set to max of 1024, we really don't need it that big. | |
6247 | * Nothing should be printing 1000 characters anyway. | |
6248 | */ | |
6249 | #define TRACE_MAX_PRINT 1000 | |
6250 | ||
6251 | /* | |
6252 | * Define here KERN_TRACE so that we have one place to modify | |
6253 | * it if we decide to change what log level the ftrace dump | |
6254 | * should be at. | |
6255 | */ | |
428aee14 | 6256 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 6257 | |
955b61e5 | 6258 | void |
3f5a54e3 SR |
6259 | trace_printk_seq(struct trace_seq *s) |
6260 | { | |
6261 | /* Probably should print a warning here. */ | |
bd6df187 J |
6262 | if (s->len >= TRACE_MAX_PRINT) |
6263 | s->len = TRACE_MAX_PRINT; | |
3f5a54e3 SR |
6264 | |
6265 | /* should be zero ended, but we are paranoid. */ | |
6266 | s->buffer[s->len] = 0; | |
6267 | ||
6268 | printk(KERN_TRACE "%s", s->buffer); | |
6269 | ||
f9520750 | 6270 | trace_seq_init(s); |
3f5a54e3 SR |
6271 | } |
6272 | ||
955b61e5 JW |
6273 | void trace_init_global_iter(struct trace_iterator *iter) |
6274 | { | |
6275 | iter->tr = &global_trace; | |
2b6080f2 | 6276 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 6277 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 6278 | iter->trace_buffer = &global_trace.trace_buffer; |
955b61e5 JW |
6279 | } |
6280 | ||
7fe70b57 | 6281 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 6282 | { |
3f5a54e3 SR |
6283 | /* use static because iter can be a bit big for the stack */ |
6284 | static struct trace_iterator iter; | |
7fe70b57 | 6285 | static atomic_t dump_running; |
cf586b61 | 6286 | unsigned int old_userobj; |
d769041f SR |
6287 | unsigned long flags; |
6288 | int cnt = 0, cpu; | |
3f5a54e3 | 6289 | |
7fe70b57 SRRH |
6290 | /* Only allow one dump user at a time. */ |
6291 | if (atomic_inc_return(&dump_running) != 1) { | |
6292 | atomic_dec(&dump_running); | |
6293 | return; | |
6294 | } | |
3f5a54e3 | 6295 | |
7fe70b57 SRRH |
6296 | /* |
6297 | * Always turn off tracing when we dump. | |
6298 | * We don't need to show trace output of what happens | |
6299 | * between multiple crashes. | |
6300 | * | |
6301 | * If the user does a sysrq-z, then they can re-enable | |
6302 | * tracing with echo 1 > tracing_on. | |
6303 | */ | |
0ee6b6cf | 6304 | tracing_off(); |
cf586b61 | 6305 | |
7fe70b57 | 6306 | local_irq_save(flags); |
3f5a54e3 | 6307 | |
38dbe0b1 | 6308 | /* Simulate the iterator */ |
955b61e5 JW |
6309 | trace_init_global_iter(&iter); |
6310 | ||
d769041f | 6311 | for_each_tracing_cpu(cpu) { |
12883efb | 6312 | atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled); |
d769041f SR |
6313 | } |
6314 | ||
cf586b61 FW |
6315 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
6316 | ||
b54d3de9 TE |
6317 | /* don't look at user memory in panic mode */ |
6318 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
6319 | ||
cecbca96 FW |
6320 | switch (oops_dump_mode) { |
6321 | case DUMP_ALL: | |
ae3b5093 | 6322 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6323 | break; |
6324 | case DUMP_ORIG: | |
6325 | iter.cpu_file = raw_smp_processor_id(); | |
6326 | break; | |
6327 | case DUMP_NONE: | |
6328 | goto out_enable; | |
6329 | default: | |
6330 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 6331 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6332 | } |
6333 | ||
6334 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 6335 | |
7fe70b57 SRRH |
6336 | /* Did function tracer already get disabled? */ |
6337 | if (ftrace_is_dead()) { | |
6338 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
6339 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
6340 | } | |
6341 | ||
3f5a54e3 SR |
6342 | /* |
6343 | * We need to stop all tracing on all CPUS to read the | |
6344 | * the next buffer. This is a bit expensive, but is | |
6345 | * not done often. We fill all what we can read, | |
6346 | * and then release the locks again. | |
6347 | */ | |
6348 | ||
3f5a54e3 SR |
6349 | while (!trace_empty(&iter)) { |
6350 | ||
6351 | if (!cnt) | |
6352 | printk(KERN_TRACE "---------------------------------\n"); | |
6353 | ||
6354 | cnt++; | |
6355 | ||
6356 | /* reset all but tr, trace, and overruns */ | |
6357 | memset(&iter.seq, 0, | |
6358 | sizeof(struct trace_iterator) - | |
6359 | offsetof(struct trace_iterator, seq)); | |
6360 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
6361 | iter.pos = -1; | |
6362 | ||
955b61e5 | 6363 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
6364 | int ret; |
6365 | ||
6366 | ret = print_trace_line(&iter); | |
6367 | if (ret != TRACE_TYPE_NO_CONSUME) | |
6368 | trace_consume(&iter); | |
3f5a54e3 | 6369 | } |
b892e5c8 | 6370 | touch_nmi_watchdog(); |
3f5a54e3 SR |
6371 | |
6372 | trace_printk_seq(&iter.seq); | |
6373 | } | |
6374 | ||
6375 | if (!cnt) | |
6376 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
6377 | else | |
6378 | printk(KERN_TRACE "---------------------------------\n"); | |
6379 | ||
cecbca96 | 6380 | out_enable: |
7fe70b57 | 6381 | trace_flags |= old_userobj; |
cf586b61 | 6382 | |
7fe70b57 SRRH |
6383 | for_each_tracing_cpu(cpu) { |
6384 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); | |
cf586b61 | 6385 | } |
7fe70b57 | 6386 | atomic_dec(&dump_running); |
cd891ae0 | 6387 | local_irq_restore(flags); |
3f5a54e3 | 6388 | } |
a8eecf22 | 6389 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 6390 | |
3928a8a2 | 6391 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 6392 | { |
73c5162a | 6393 | int ring_buf_size; |
9e01c1b7 | 6394 | int ret = -ENOMEM; |
4c11d7ae | 6395 | |
750912fa | 6396 | |
9e01c1b7 RR |
6397 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
6398 | goto out; | |
6399 | ||
ccfe9e42 | 6400 | if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) |
9e01c1b7 | 6401 | goto out_free_buffer_mask; |
4c11d7ae | 6402 | |
07d777fe SR |
6403 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
6404 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 6405 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
6406 | trace_printk_init_buffers(); |
6407 | ||
73c5162a SR |
6408 | /* To save memory, keep the ring buffer size to its minimum */ |
6409 | if (ring_buffer_expanded) | |
6410 | ring_buf_size = trace_buf_size; | |
6411 | else | |
6412 | ring_buf_size = 1; | |
6413 | ||
9e01c1b7 | 6414 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
ccfe9e42 | 6415 | cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); |
9e01c1b7 | 6416 | |
2b6080f2 SR |
6417 | raw_spin_lock_init(&global_trace.start_lock); |
6418 | ||
9e01c1b7 | 6419 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 6420 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
6421 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
6422 | WARN_ON(1); | |
9e01c1b7 | 6423 | goto out_free_cpumask; |
4c11d7ae | 6424 | } |
a7603ff4 | 6425 | |
499e5470 SR |
6426 | if (global_trace.buffer_disabled) |
6427 | tracing_off(); | |
4c11d7ae | 6428 | |
bc0c38d1 SR |
6429 | trace_init_cmdlines(); |
6430 | ||
ca164318 SRRH |
6431 | /* |
6432 | * register_tracer() might reference current_trace, so it | |
6433 | * needs to be set before we register anything. This is | |
6434 | * just a bootstrap of current_trace anyway. | |
6435 | */ | |
2b6080f2 SR |
6436 | global_trace.current_trace = &nop_trace; |
6437 | ||
ca164318 SRRH |
6438 | register_tracer(&nop_trace); |
6439 | ||
60a11774 SR |
6440 | /* All seems OK, enable tracing */ |
6441 | tracing_disabled = 0; | |
3928a8a2 | 6442 | |
3f5a54e3 SR |
6443 | atomic_notifier_chain_register(&panic_notifier_list, |
6444 | &trace_panic_notifier); | |
6445 | ||
6446 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 6447 | |
ae63b31e SR |
6448 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
6449 | ||
6450 | INIT_LIST_HEAD(&global_trace.systems); | |
6451 | INIT_LIST_HEAD(&global_trace.events); | |
6452 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
6453 | ||
7bcfaf54 SR |
6454 | while (trace_boot_options) { |
6455 | char *option; | |
6456 | ||
6457 | option = strsep(&trace_boot_options, ","); | |
2b6080f2 | 6458 | trace_set_options(&global_trace, option); |
7bcfaf54 SR |
6459 | } |
6460 | ||
77fd5c15 SRRH |
6461 | register_snapshot_cmd(); |
6462 | ||
2fc1dfbe | 6463 | return 0; |
3f5a54e3 | 6464 | |
9e01c1b7 | 6465 | out_free_cpumask: |
12883efb SRRH |
6466 | free_percpu(global_trace.trace_buffer.data); |
6467 | #ifdef CONFIG_TRACER_MAX_TRACE | |
6468 | free_percpu(global_trace.max_buffer.data); | |
6469 | #endif | |
ccfe9e42 | 6470 | free_cpumask_var(global_trace.tracing_cpumask); |
9e01c1b7 RR |
6471 | out_free_buffer_mask: |
6472 | free_cpumask_var(tracing_buffer_mask); | |
6473 | out: | |
6474 | return ret; | |
bc0c38d1 | 6475 | } |
b2821ae6 SR |
6476 | |
6477 | __init static int clear_boot_tracer(void) | |
6478 | { | |
6479 | /* | |
6480 | * The default tracer at boot buffer is an init section. | |
6481 | * This function is called in lateinit. If we did not | |
6482 | * find the boot tracer, then clear it out, to prevent | |
6483 | * later registration from accessing the buffer that is | |
6484 | * about to be freed. | |
6485 | */ | |
6486 | if (!default_bootup_tracer) | |
6487 | return 0; | |
6488 | ||
6489 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
6490 | default_bootup_tracer); | |
6491 | default_bootup_tracer = NULL; | |
6492 | ||
6493 | return 0; | |
6494 | } | |
6495 | ||
b5ad384e FW |
6496 | early_initcall(tracer_alloc_buffers); |
6497 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 6498 | late_initcall(clear_boot_tracer); |