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 | ||
8c1a49ae SRRH |
76 | static int |
77 | dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) | |
adf9f195 FW |
78 | { |
79 | return 0; | |
80 | } | |
0f048701 | 81 | |
7ffbd48d SR |
82 | /* |
83 | * To prevent the comm cache from being overwritten when no | |
84 | * tracing is active, only save the comm when a trace event | |
85 | * occurred. | |
86 | */ | |
87 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
88 | ||
0f048701 SR |
89 | /* |
90 | * Kill all tracing for good (never come back). | |
91 | * It is initialized to 1 but will turn to zero if the initialization | |
92 | * of the tracer is successful. But that is the only place that sets | |
93 | * this back to zero. | |
94 | */ | |
4fd27358 | 95 | static int tracing_disabled = 1; |
0f048701 | 96 | |
9288f99a | 97 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 98 | |
955b61e5 | 99 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 100 | |
944ac425 SR |
101 | /* |
102 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
103 | * | |
104 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
105 | * is set, then ftrace_dump is called. This will output the contents | |
106 | * of the ftrace buffers to the console. This is very useful for | |
107 | * capturing traces that lead to crashes and outputing it to a | |
108 | * serial console. | |
109 | * | |
110 | * It is default off, but you can enable it with either specifying | |
111 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
112 | * /proc/sys/kernel/ftrace_dump_on_oops |
113 | * Set 1 if you want to dump buffers of all CPUs | |
114 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 115 | */ |
cecbca96 FW |
116 | |
117 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 118 | |
de7edd31 SRRH |
119 | /* When set, tracing will stop when a WARN*() is hit */ |
120 | int __disable_trace_on_warning; | |
121 | ||
607e2ea1 | 122 | static int tracing_set_tracer(struct trace_array *tr, const char *buf); |
b2821ae6 | 123 | |
ee6c2c1b LZ |
124 | #define MAX_TRACER_SIZE 100 |
125 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 126 | static char *default_bootup_tracer; |
d9e54076 | 127 | |
55034cd6 SRRH |
128 | static bool allocate_snapshot; |
129 | ||
1beee96b | 130 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 131 | { |
67012ab1 | 132 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 133 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 134 | /* We are using ftrace early, expand it */ |
55034cd6 | 135 | ring_buffer_expanded = true; |
d9e54076 PZ |
136 | return 1; |
137 | } | |
1beee96b | 138 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 139 | |
944ac425 SR |
140 | static int __init set_ftrace_dump_on_oops(char *str) |
141 | { | |
cecbca96 FW |
142 | if (*str++ != '=' || !*str) { |
143 | ftrace_dump_on_oops = DUMP_ALL; | |
144 | return 1; | |
145 | } | |
146 | ||
147 | if (!strcmp("orig_cpu", str)) { | |
148 | ftrace_dump_on_oops = DUMP_ORIG; | |
149 | return 1; | |
150 | } | |
151 | ||
152 | return 0; | |
944ac425 SR |
153 | } |
154 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 155 | |
de7edd31 SRRH |
156 | static int __init stop_trace_on_warning(char *str) |
157 | { | |
158 | __disable_trace_on_warning = 1; | |
159 | return 1; | |
160 | } | |
161 | __setup("traceoff_on_warning=", stop_trace_on_warning); | |
162 | ||
3209cff4 | 163 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
164 | { |
165 | allocate_snapshot = true; | |
166 | /* We also need the main ring buffer expanded */ | |
167 | ring_buffer_expanded = true; | |
168 | return 1; | |
169 | } | |
3209cff4 | 170 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 171 | |
7bcfaf54 SR |
172 | |
173 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
174 | static char *trace_boot_options __initdata; | |
175 | ||
176 | static int __init set_trace_boot_options(char *str) | |
177 | { | |
67012ab1 | 178 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
179 | trace_boot_options = trace_boot_options_buf; |
180 | return 0; | |
181 | } | |
182 | __setup("trace_options=", set_trace_boot_options); | |
183 | ||
e1e232ca SR |
184 | static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; |
185 | static char *trace_boot_clock __initdata; | |
186 | ||
187 | static int __init set_trace_boot_clock(char *str) | |
188 | { | |
189 | strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); | |
190 | trace_boot_clock = trace_boot_clock_buf; | |
191 | return 0; | |
192 | } | |
193 | __setup("trace_clock=", set_trace_boot_clock); | |
194 | ||
de7edd31 | 195 | |
cf8e3474 | 196 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
197 | { |
198 | nsec += 500; | |
199 | do_div(nsec, 1000); | |
200 | return nsec; | |
201 | } | |
202 | ||
4fcdae83 SR |
203 | /* |
204 | * The global_trace is the descriptor that holds the tracing | |
205 | * buffers for the live tracing. For each CPU, it contains | |
206 | * a link list of pages that will store trace entries. The | |
207 | * page descriptor of the pages in the memory is used to hold | |
208 | * the link list by linking the lru item in the page descriptor | |
209 | * to each of the pages in the buffer per CPU. | |
210 | * | |
211 | * For each active CPU there is a data field that holds the | |
212 | * pages for the buffer for that CPU. Each CPU has the same number | |
213 | * of pages allocated for its buffer. | |
214 | */ | |
bc0c38d1 SR |
215 | static struct trace_array global_trace; |
216 | ||
ae63b31e | 217 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 218 | |
ff451961 SRRH |
219 | int trace_array_get(struct trace_array *this_tr) |
220 | { | |
221 | struct trace_array *tr; | |
222 | int ret = -ENODEV; | |
223 | ||
224 | mutex_lock(&trace_types_lock); | |
225 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
226 | if (tr == this_tr) { | |
227 | tr->ref++; | |
228 | ret = 0; | |
229 | break; | |
230 | } | |
231 | } | |
232 | mutex_unlock(&trace_types_lock); | |
233 | ||
234 | return ret; | |
235 | } | |
236 | ||
237 | static void __trace_array_put(struct trace_array *this_tr) | |
238 | { | |
239 | WARN_ON(!this_tr->ref); | |
240 | this_tr->ref--; | |
241 | } | |
242 | ||
243 | void trace_array_put(struct trace_array *this_tr) | |
244 | { | |
245 | mutex_lock(&trace_types_lock); | |
246 | __trace_array_put(this_tr); | |
247 | mutex_unlock(&trace_types_lock); | |
248 | } | |
249 | ||
f306cc82 TZ |
250 | int filter_check_discard(struct ftrace_event_file *file, void *rec, |
251 | struct ring_buffer *buffer, | |
252 | struct ring_buffer_event *event) | |
eb02ce01 | 253 | { |
f306cc82 TZ |
254 | if (unlikely(file->flags & FTRACE_EVENT_FL_FILTERED) && |
255 | !filter_match_preds(file->filter, rec)) { | |
256 | ring_buffer_discard_commit(buffer, event); | |
257 | return 1; | |
258 | } | |
259 | ||
260 | return 0; | |
261 | } | |
262 | EXPORT_SYMBOL_GPL(filter_check_discard); | |
263 | ||
264 | int call_filter_check_discard(struct ftrace_event_call *call, void *rec, | |
265 | struct ring_buffer *buffer, | |
266 | struct ring_buffer_event *event) | |
267 | { | |
268 | if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && | |
269 | !filter_match_preds(call->filter, rec)) { | |
270 | ring_buffer_discard_commit(buffer, event); | |
271 | return 1; | |
272 | } | |
273 | ||
274 | return 0; | |
eb02ce01 | 275 | } |
f306cc82 | 276 | EXPORT_SYMBOL_GPL(call_filter_check_discard); |
eb02ce01 | 277 | |
ad1438a0 | 278 | static cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) |
37886f6a SR |
279 | { |
280 | u64 ts; | |
281 | ||
282 | /* Early boot up does not have a buffer yet */ | |
9457158b | 283 | if (!buf->buffer) |
37886f6a SR |
284 | return trace_clock_local(); |
285 | ||
9457158b AL |
286 | ts = ring_buffer_time_stamp(buf->buffer, cpu); |
287 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); | |
37886f6a SR |
288 | |
289 | return ts; | |
290 | } | |
bc0c38d1 | 291 | |
9457158b AL |
292 | cycle_t ftrace_now(int cpu) |
293 | { | |
294 | return buffer_ftrace_now(&global_trace.trace_buffer, cpu); | |
295 | } | |
296 | ||
10246fa3 SRRH |
297 | /** |
298 | * tracing_is_enabled - Show if global_trace has been disabled | |
299 | * | |
300 | * Shows if the global trace has been enabled or not. It uses the | |
301 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
302 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
303 | * need to know the accurate state, use tracing_is_on() which is a little | |
304 | * slower, but accurate. | |
305 | */ | |
9036990d SR |
306 | int tracing_is_enabled(void) |
307 | { | |
10246fa3 SRRH |
308 | /* |
309 | * For quick access (irqsoff uses this in fast path), just | |
310 | * return the mirror variable of the state of the ring buffer. | |
311 | * It's a little racy, but we don't really care. | |
312 | */ | |
313 | smp_rmb(); | |
314 | return !global_trace.buffer_disabled; | |
9036990d SR |
315 | } |
316 | ||
4fcdae83 | 317 | /* |
3928a8a2 SR |
318 | * trace_buf_size is the size in bytes that is allocated |
319 | * for a buffer. Note, the number of bytes is always rounded | |
320 | * to page size. | |
3f5a54e3 SR |
321 | * |
322 | * This number is purposely set to a low number of 16384. | |
323 | * If the dump on oops happens, it will be much appreciated | |
324 | * to not have to wait for all that output. Anyway this can be | |
325 | * boot time and run time configurable. | |
4fcdae83 | 326 | */ |
3928a8a2 | 327 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 328 | |
3928a8a2 | 329 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 330 | |
4fcdae83 | 331 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 332 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 333 | |
4fcdae83 SR |
334 | /* |
335 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 336 | */ |
a8227415 | 337 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 338 | |
7e53bd42 LJ |
339 | /* |
340 | * serialize the access of the ring buffer | |
341 | * | |
342 | * ring buffer serializes readers, but it is low level protection. | |
343 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
344 | * are not protected by ring buffer. | |
345 | * | |
346 | * The content of events may become garbage if we allow other process consumes | |
347 | * these events concurrently: | |
348 | * A) the page of the consumed events may become a normal page | |
349 | * (not reader page) in ring buffer, and this page will be rewrited | |
350 | * by events producer. | |
351 | * B) The page of the consumed events may become a page for splice_read, | |
352 | * and this page will be returned to system. | |
353 | * | |
354 | * These primitives allow multi process access to different cpu ring buffer | |
355 | * concurrently. | |
356 | * | |
357 | * These primitives don't distinguish read-only and read-consume access. | |
358 | * Multi read-only access are also serialized. | |
359 | */ | |
360 | ||
361 | #ifdef CONFIG_SMP | |
362 | static DECLARE_RWSEM(all_cpu_access_lock); | |
363 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
364 | ||
365 | static inline void trace_access_lock(int cpu) | |
366 | { | |
ae3b5093 | 367 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
368 | /* gain it for accessing the whole ring buffer. */ |
369 | down_write(&all_cpu_access_lock); | |
370 | } else { | |
371 | /* gain it for accessing a cpu ring buffer. */ | |
372 | ||
ae3b5093 | 373 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
374 | down_read(&all_cpu_access_lock); |
375 | ||
376 | /* Secondly block other access to this @cpu ring buffer. */ | |
377 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
378 | } | |
379 | } | |
380 | ||
381 | static inline void trace_access_unlock(int cpu) | |
382 | { | |
ae3b5093 | 383 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
384 | up_write(&all_cpu_access_lock); |
385 | } else { | |
386 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
387 | up_read(&all_cpu_access_lock); | |
388 | } | |
389 | } | |
390 | ||
391 | static inline void trace_access_lock_init(void) | |
392 | { | |
393 | int cpu; | |
394 | ||
395 | for_each_possible_cpu(cpu) | |
396 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
397 | } | |
398 | ||
399 | #else | |
400 | ||
401 | static DEFINE_MUTEX(access_lock); | |
402 | ||
403 | static inline void trace_access_lock(int cpu) | |
404 | { | |
405 | (void)cpu; | |
406 | mutex_lock(&access_lock); | |
407 | } | |
408 | ||
409 | static inline void trace_access_unlock(int cpu) | |
410 | { | |
411 | (void)cpu; | |
412 | mutex_unlock(&access_lock); | |
413 | } | |
414 | ||
415 | static inline void trace_access_lock_init(void) | |
416 | { | |
417 | } | |
418 | ||
419 | #endif | |
420 | ||
ee6bce52 | 421 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 422 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 423 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 | 424 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
328df475 | 425 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION; |
e7e2ee89 | 426 | |
5280bcef | 427 | static void tracer_tracing_on(struct trace_array *tr) |
10246fa3 SRRH |
428 | { |
429 | if (tr->trace_buffer.buffer) | |
430 | ring_buffer_record_on(tr->trace_buffer.buffer); | |
431 | /* | |
432 | * This flag is looked at when buffers haven't been allocated | |
433 | * yet, or by some tracers (like irqsoff), that just want to | |
434 | * know if the ring buffer has been disabled, but it can handle | |
435 | * races of where it gets disabled but we still do a record. | |
436 | * As the check is in the fast path of the tracers, it is more | |
437 | * important to be fast than accurate. | |
438 | */ | |
439 | tr->buffer_disabled = 0; | |
440 | /* Make the flag seen by readers */ | |
441 | smp_wmb(); | |
442 | } | |
443 | ||
499e5470 SR |
444 | /** |
445 | * tracing_on - enable tracing buffers | |
446 | * | |
447 | * This function enables tracing buffers that may have been | |
448 | * disabled with tracing_off. | |
449 | */ | |
450 | void tracing_on(void) | |
451 | { | |
10246fa3 | 452 | tracer_tracing_on(&global_trace); |
499e5470 SR |
453 | } |
454 | EXPORT_SYMBOL_GPL(tracing_on); | |
455 | ||
09ae7234 SRRH |
456 | /** |
457 | * __trace_puts - write a constant string into the trace buffer. | |
458 | * @ip: The address of the caller | |
459 | * @str: The constant string to write | |
460 | * @size: The size of the string. | |
461 | */ | |
462 | int __trace_puts(unsigned long ip, const char *str, int size) | |
463 | { | |
464 | struct ring_buffer_event *event; | |
465 | struct ring_buffer *buffer; | |
466 | struct print_entry *entry; | |
467 | unsigned long irq_flags; | |
468 | int alloc; | |
469 | ||
3132e107 SRRH |
470 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
471 | return 0; | |
472 | ||
09ae7234 SRRH |
473 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ |
474 | ||
475 | local_save_flags(irq_flags); | |
476 | buffer = global_trace.trace_buffer.buffer; | |
477 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, | |
478 | irq_flags, preempt_count()); | |
479 | if (!event) | |
480 | return 0; | |
481 | ||
482 | entry = ring_buffer_event_data(event); | |
483 | entry->ip = ip; | |
484 | ||
485 | memcpy(&entry->buf, str, size); | |
486 | ||
487 | /* Add a newline if necessary */ | |
488 | if (entry->buf[size - 1] != '\n') { | |
489 | entry->buf[size] = '\n'; | |
490 | entry->buf[size + 1] = '\0'; | |
491 | } else | |
492 | entry->buf[size] = '\0'; | |
493 | ||
494 | __buffer_unlock_commit(buffer, event); | |
495 | ||
496 | return size; | |
497 | } | |
498 | EXPORT_SYMBOL_GPL(__trace_puts); | |
499 | ||
500 | /** | |
501 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
502 | * @ip: The address of the caller | |
503 | * @str: The constant string to write to the buffer to | |
504 | */ | |
505 | int __trace_bputs(unsigned long ip, const char *str) | |
506 | { | |
507 | struct ring_buffer_event *event; | |
508 | struct ring_buffer *buffer; | |
509 | struct bputs_entry *entry; | |
510 | unsigned long irq_flags; | |
511 | int size = sizeof(struct bputs_entry); | |
512 | ||
3132e107 SRRH |
513 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
514 | return 0; | |
515 | ||
09ae7234 SRRH |
516 | local_save_flags(irq_flags); |
517 | buffer = global_trace.trace_buffer.buffer; | |
518 | event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, | |
519 | irq_flags, preempt_count()); | |
520 | if (!event) | |
521 | return 0; | |
522 | ||
523 | entry = ring_buffer_event_data(event); | |
524 | entry->ip = ip; | |
525 | entry->str = str; | |
526 | ||
527 | __buffer_unlock_commit(buffer, event); | |
528 | ||
529 | return 1; | |
530 | } | |
531 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
532 | ||
ad909e21 SRRH |
533 | #ifdef CONFIG_TRACER_SNAPSHOT |
534 | /** | |
535 | * trace_snapshot - take a snapshot of the current buffer. | |
536 | * | |
537 | * This causes a swap between the snapshot buffer and the current live | |
538 | * tracing buffer. You can use this to take snapshots of the live | |
539 | * trace when some condition is triggered, but continue to trace. | |
540 | * | |
541 | * Note, make sure to allocate the snapshot with either | |
542 | * a tracing_snapshot_alloc(), or by doing it manually | |
543 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
544 | * | |
545 | * If the snapshot buffer is not allocated, it will stop tracing. | |
546 | * Basically making a permanent snapshot. | |
547 | */ | |
548 | void tracing_snapshot(void) | |
549 | { | |
550 | struct trace_array *tr = &global_trace; | |
551 | struct tracer *tracer = tr->current_trace; | |
552 | unsigned long flags; | |
553 | ||
1b22e382 SRRH |
554 | if (in_nmi()) { |
555 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
556 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
557 | return; | |
558 | } | |
559 | ||
ad909e21 | 560 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
561 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
562 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
563 | tracing_off(); |
564 | return; | |
565 | } | |
566 | ||
567 | /* Note, snapshot can not be used when the tracer uses it */ | |
568 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
569 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
570 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
571 | return; |
572 | } | |
573 | ||
574 | local_irq_save(flags); | |
575 | update_max_tr(tr, current, smp_processor_id()); | |
576 | local_irq_restore(flags); | |
577 | } | |
1b22e382 | 578 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
579 | |
580 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
581 | struct trace_buffer *size_buf, int cpu_id); | |
3209cff4 SRRH |
582 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); |
583 | ||
584 | static int alloc_snapshot(struct trace_array *tr) | |
585 | { | |
586 | int ret; | |
587 | ||
588 | if (!tr->allocated_snapshot) { | |
589 | ||
590 | /* allocate spare buffer */ | |
591 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
592 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
593 | if (ret < 0) | |
594 | return ret; | |
595 | ||
596 | tr->allocated_snapshot = true; | |
597 | } | |
598 | ||
599 | return 0; | |
600 | } | |
601 | ||
ad1438a0 | 602 | static void free_snapshot(struct trace_array *tr) |
3209cff4 SRRH |
603 | { |
604 | /* | |
605 | * We don't free the ring buffer. instead, resize it because | |
606 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
607 | * we want preserve it. | |
608 | */ | |
609 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
610 | set_buffer_entries(&tr->max_buffer, 1); | |
611 | tracing_reset_online_cpus(&tr->max_buffer); | |
612 | tr->allocated_snapshot = false; | |
613 | } | |
ad909e21 | 614 | |
93e31ffb TZ |
615 | /** |
616 | * tracing_alloc_snapshot - allocate snapshot buffer. | |
617 | * | |
618 | * This only allocates the snapshot buffer if it isn't already | |
619 | * allocated - it doesn't also take a snapshot. | |
620 | * | |
621 | * This is meant to be used in cases where the snapshot buffer needs | |
622 | * to be set up for events that can't sleep but need to be able to | |
623 | * trigger a snapshot. | |
624 | */ | |
625 | int tracing_alloc_snapshot(void) | |
626 | { | |
627 | struct trace_array *tr = &global_trace; | |
628 | int ret; | |
629 | ||
630 | ret = alloc_snapshot(tr); | |
631 | WARN_ON(ret < 0); | |
632 | ||
633 | return ret; | |
634 | } | |
635 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
636 | ||
ad909e21 SRRH |
637 | /** |
638 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
639 | * | |
640 | * This is similar to trace_snapshot(), but it will allocate the | |
641 | * snapshot buffer if it isn't already allocated. Use this only | |
642 | * where it is safe to sleep, as the allocation may sleep. | |
643 | * | |
644 | * This causes a swap between the snapshot buffer and the current live | |
645 | * tracing buffer. You can use this to take snapshots of the live | |
646 | * trace when some condition is triggered, but continue to trace. | |
647 | */ | |
648 | void tracing_snapshot_alloc(void) | |
649 | { | |
ad909e21 SRRH |
650 | int ret; |
651 | ||
93e31ffb TZ |
652 | ret = tracing_alloc_snapshot(); |
653 | if (ret < 0) | |
3209cff4 | 654 | return; |
ad909e21 SRRH |
655 | |
656 | tracing_snapshot(); | |
657 | } | |
1b22e382 | 658 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
659 | #else |
660 | void tracing_snapshot(void) | |
661 | { | |
662 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
663 | } | |
1b22e382 | 664 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
93e31ffb TZ |
665 | int tracing_alloc_snapshot(void) |
666 | { | |
667 | WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); | |
668 | return -ENODEV; | |
669 | } | |
670 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
ad909e21 SRRH |
671 | void tracing_snapshot_alloc(void) |
672 | { | |
673 | /* Give warning */ | |
674 | tracing_snapshot(); | |
675 | } | |
1b22e382 | 676 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
677 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
678 | ||
5280bcef | 679 | static void tracer_tracing_off(struct trace_array *tr) |
10246fa3 SRRH |
680 | { |
681 | if (tr->trace_buffer.buffer) | |
682 | ring_buffer_record_off(tr->trace_buffer.buffer); | |
683 | /* | |
684 | * This flag is looked at when buffers haven't been allocated | |
685 | * yet, or by some tracers (like irqsoff), that just want to | |
686 | * know if the ring buffer has been disabled, but it can handle | |
687 | * races of where it gets disabled but we still do a record. | |
688 | * As the check is in the fast path of the tracers, it is more | |
689 | * important to be fast than accurate. | |
690 | */ | |
691 | tr->buffer_disabled = 1; | |
692 | /* Make the flag seen by readers */ | |
693 | smp_wmb(); | |
694 | } | |
695 | ||
499e5470 SR |
696 | /** |
697 | * tracing_off - turn off tracing buffers | |
698 | * | |
699 | * This function stops the tracing buffers from recording data. | |
700 | * It does not disable any overhead the tracers themselves may | |
701 | * be causing. This function simply causes all recording to | |
702 | * the ring buffers to fail. | |
703 | */ | |
704 | void tracing_off(void) | |
705 | { | |
10246fa3 | 706 | tracer_tracing_off(&global_trace); |
499e5470 SR |
707 | } |
708 | EXPORT_SYMBOL_GPL(tracing_off); | |
709 | ||
de7edd31 SRRH |
710 | void disable_trace_on_warning(void) |
711 | { | |
712 | if (__disable_trace_on_warning) | |
713 | tracing_off(); | |
714 | } | |
715 | ||
10246fa3 SRRH |
716 | /** |
717 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
718 | * @tr : the trace array to know if ring buffer is enabled | |
719 | * | |
720 | * Shows real state of the ring buffer if it is enabled or not. | |
721 | */ | |
5280bcef | 722 | static int tracer_tracing_is_on(struct trace_array *tr) |
10246fa3 SRRH |
723 | { |
724 | if (tr->trace_buffer.buffer) | |
725 | return ring_buffer_record_is_on(tr->trace_buffer.buffer); | |
726 | return !tr->buffer_disabled; | |
727 | } | |
728 | ||
499e5470 SR |
729 | /** |
730 | * tracing_is_on - show state of ring buffers enabled | |
731 | */ | |
732 | int tracing_is_on(void) | |
733 | { | |
10246fa3 | 734 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
735 | } |
736 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
737 | ||
3928a8a2 | 738 | static int __init set_buf_size(char *str) |
bc0c38d1 | 739 | { |
3928a8a2 | 740 | unsigned long buf_size; |
c6caeeb1 | 741 | |
bc0c38d1 SR |
742 | if (!str) |
743 | return 0; | |
9d612bef | 744 | buf_size = memparse(str, &str); |
c6caeeb1 | 745 | /* nr_entries can not be zero */ |
9d612bef | 746 | if (buf_size == 0) |
c6caeeb1 | 747 | return 0; |
3928a8a2 | 748 | trace_buf_size = buf_size; |
bc0c38d1 SR |
749 | return 1; |
750 | } | |
3928a8a2 | 751 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 752 | |
0e950173 TB |
753 | static int __init set_tracing_thresh(char *str) |
754 | { | |
87abb3b1 | 755 | unsigned long threshold; |
0e950173 TB |
756 | int ret; |
757 | ||
758 | if (!str) | |
759 | return 0; | |
bcd83ea6 | 760 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
761 | if (ret < 0) |
762 | return 0; | |
87abb3b1 | 763 | tracing_thresh = threshold * 1000; |
0e950173 TB |
764 | return 1; |
765 | } | |
766 | __setup("tracing_thresh=", set_tracing_thresh); | |
767 | ||
57f50be1 SR |
768 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
769 | { | |
770 | return nsecs / 1000; | |
771 | } | |
772 | ||
4fcdae83 | 773 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
774 | static const char *trace_options[] = { |
775 | "print-parent", | |
776 | "sym-offset", | |
777 | "sym-addr", | |
778 | "verbose", | |
f9896bf3 | 779 | "raw", |
5e3ca0ec | 780 | "hex", |
cb0f12aa | 781 | "bin", |
2a2cc8f7 | 782 | "block", |
86387f7e | 783 | "stacktrace", |
5e1607a0 | 784 | "trace_printk", |
b2a866f9 | 785 | "ftrace_preempt", |
9f029e83 | 786 | "branch", |
12ef7d44 | 787 | "annotate", |
02b67518 | 788 | "userstacktrace", |
b54d3de9 | 789 | "sym-userobj", |
66896a85 | 790 | "printk-msg-only", |
c4a8e8be | 791 | "context-info", |
c032ef64 | 792 | "latency-format", |
be6f164a | 793 | "sleep-time", |
a2a16d6a | 794 | "graph-time", |
e870e9a1 | 795 | "record-cmd", |
750912fa | 796 | "overwrite", |
cf30cf67 | 797 | "disable_on_free", |
77271ce4 | 798 | "irq-info", |
5224c3a3 | 799 | "markers", |
328df475 | 800 | "function-trace", |
bc0c38d1 SR |
801 | NULL |
802 | }; | |
803 | ||
5079f326 Z |
804 | static struct { |
805 | u64 (*func)(void); | |
806 | const char *name; | |
8be0709f | 807 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 808 | } trace_clocks[] = { |
8be0709f DS |
809 | { trace_clock_local, "local", 1 }, |
810 | { trace_clock_global, "global", 1 }, | |
811 | { trace_clock_counter, "counter", 0 }, | |
8aacf017 | 812 | { trace_clock_jiffies, "uptime", 1 }, |
76f11917 | 813 | { trace_clock, "perf", 1 }, |
8cbd9cc6 | 814 | ARCH_TRACE_CLOCKS |
5079f326 Z |
815 | }; |
816 | ||
b63f39ea | 817 | /* |
818 | * trace_parser_get_init - gets the buffer for trace parser | |
819 | */ | |
820 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
821 | { | |
822 | memset(parser, 0, sizeof(*parser)); | |
823 | ||
824 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
825 | if (!parser->buffer) | |
826 | return 1; | |
827 | ||
828 | parser->size = size; | |
829 | return 0; | |
830 | } | |
831 | ||
832 | /* | |
833 | * trace_parser_put - frees the buffer for trace parser | |
834 | */ | |
835 | void trace_parser_put(struct trace_parser *parser) | |
836 | { | |
837 | kfree(parser->buffer); | |
838 | } | |
839 | ||
840 | /* | |
841 | * trace_get_user - reads the user input string separated by space | |
842 | * (matched by isspace(ch)) | |
843 | * | |
844 | * For each string found the 'struct trace_parser' is updated, | |
845 | * and the function returns. | |
846 | * | |
847 | * Returns number of bytes read. | |
848 | * | |
849 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
850 | */ | |
851 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
852 | size_t cnt, loff_t *ppos) | |
853 | { | |
854 | char ch; | |
855 | size_t read = 0; | |
856 | ssize_t ret; | |
857 | ||
858 | if (!*ppos) | |
859 | trace_parser_clear(parser); | |
860 | ||
861 | ret = get_user(ch, ubuf++); | |
862 | if (ret) | |
863 | goto out; | |
864 | ||
865 | read++; | |
866 | cnt--; | |
867 | ||
868 | /* | |
869 | * The parser is not finished with the last write, | |
870 | * continue reading the user input without skipping spaces. | |
871 | */ | |
872 | if (!parser->cont) { | |
873 | /* skip white space */ | |
874 | while (cnt && isspace(ch)) { | |
875 | ret = get_user(ch, ubuf++); | |
876 | if (ret) | |
877 | goto out; | |
878 | read++; | |
879 | cnt--; | |
880 | } | |
881 | ||
882 | /* only spaces were written */ | |
883 | if (isspace(ch)) { | |
884 | *ppos += read; | |
885 | ret = read; | |
886 | goto out; | |
887 | } | |
888 | ||
889 | parser->idx = 0; | |
890 | } | |
891 | ||
892 | /* read the non-space input */ | |
893 | while (cnt && !isspace(ch)) { | |
3c235a33 | 894 | if (parser->idx < parser->size - 1) |
b63f39ea | 895 | parser->buffer[parser->idx++] = ch; |
896 | else { | |
897 | ret = -EINVAL; | |
898 | goto out; | |
899 | } | |
900 | ret = get_user(ch, ubuf++); | |
901 | if (ret) | |
902 | goto out; | |
903 | read++; | |
904 | cnt--; | |
905 | } | |
906 | ||
907 | /* We either got finished input or we have to wait for another call. */ | |
908 | if (isspace(ch)) { | |
909 | parser->buffer[parser->idx] = 0; | |
910 | parser->cont = false; | |
057db848 | 911 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 912 | parser->cont = true; |
913 | parser->buffer[parser->idx++] = ch; | |
057db848 SR |
914 | } else { |
915 | ret = -EINVAL; | |
916 | goto out; | |
b63f39ea | 917 | } |
918 | ||
919 | *ppos += read; | |
920 | ret = read; | |
921 | ||
922 | out: | |
923 | return ret; | |
924 | } | |
925 | ||
6c6c2796 PP |
926 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
927 | { | |
928 | int len; | |
929 | int ret; | |
930 | ||
2dc5d12b SR |
931 | if (!cnt) |
932 | return 0; | |
933 | ||
6c6c2796 PP |
934 | if (s->len <= s->readpos) |
935 | return -EBUSY; | |
936 | ||
937 | len = s->len - s->readpos; | |
938 | if (cnt > len) | |
939 | cnt = len; | |
940 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 941 | if (ret == cnt) |
6c6c2796 PP |
942 | return -EFAULT; |
943 | ||
2dc5d12b SR |
944 | cnt -= ret; |
945 | ||
e74da523 | 946 | s->readpos += cnt; |
6c6c2796 | 947 | return cnt; |
214023c3 SR |
948 | } |
949 | ||
b8b94265 | 950 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
951 | { |
952 | int len; | |
3c56819b EGM |
953 | |
954 | if (s->len <= s->readpos) | |
955 | return -EBUSY; | |
956 | ||
957 | len = s->len - s->readpos; | |
958 | if (cnt > len) | |
959 | cnt = len; | |
5a26c8f0 | 960 | memcpy(buf, s->buffer + s->readpos, cnt); |
3c56819b | 961 | |
e74da523 | 962 | s->readpos += cnt; |
3c56819b EGM |
963 | return cnt; |
964 | } | |
965 | ||
0e950173 TB |
966 | unsigned long __read_mostly tracing_thresh; |
967 | ||
5d4a9dba | 968 | #ifdef CONFIG_TRACER_MAX_TRACE |
5d4a9dba SR |
969 | /* |
970 | * Copy the new maximum trace into the separate maximum-trace | |
971 | * structure. (this way the maximum trace is permanently saved, | |
972 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
973 | */ | |
974 | static void | |
975 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
976 | { | |
12883efb SRRH |
977 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
978 | struct trace_buffer *max_buf = &tr->max_buffer; | |
979 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
980 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 981 | |
12883efb SRRH |
982 | max_buf->cpu = cpu; |
983 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 984 | |
6d9b3fa5 | 985 | max_data->saved_latency = tr->max_latency; |
8248ac05 SR |
986 | max_data->critical_start = data->critical_start; |
987 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 988 | |
1acaa1b2 | 989 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 990 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
991 | /* |
992 | * If tsk == current, then use current_uid(), as that does not use | |
993 | * RCU. The irq tracer can be called out of RCU scope. | |
994 | */ | |
995 | if (tsk == current) | |
996 | max_data->uid = current_uid(); | |
997 | else | |
998 | max_data->uid = task_uid(tsk); | |
999 | ||
8248ac05 SR |
1000 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
1001 | max_data->policy = tsk->policy; | |
1002 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
1003 | |
1004 | /* record this tasks comm */ | |
1005 | tracing_record_cmdline(tsk); | |
1006 | } | |
1007 | ||
4fcdae83 SR |
1008 | /** |
1009 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
1010 | * @tr: tracer | |
1011 | * @tsk: the task with the latency | |
1012 | * @cpu: The cpu that initiated the trace. | |
1013 | * | |
1014 | * Flip the buffers between the @tr and the max_tr and record information | |
1015 | * about which task was the cause of this latency. | |
1016 | */ | |
e309b41d | 1017 | void |
bc0c38d1 SR |
1018 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1019 | { | |
2721e72d | 1020 | struct ring_buffer *buf; |
bc0c38d1 | 1021 | |
2b6080f2 | 1022 | if (tr->stop_count) |
b8de7bd1 SR |
1023 | return; |
1024 | ||
4c11d7ae | 1025 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 1026 | |
45ad21ca | 1027 | if (!tr->allocated_snapshot) { |
debdd57f | 1028 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 1029 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 1030 | return; |
debdd57f | 1031 | } |
34600f0e | 1032 | |
0b9b12c1 | 1033 | arch_spin_lock(&tr->max_lock); |
3928a8a2 | 1034 | |
12883efb SRRH |
1035 | buf = tr->trace_buffer.buffer; |
1036 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
1037 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 1038 | |
bc0c38d1 | 1039 | __update_max_tr(tr, tsk, cpu); |
0b9b12c1 | 1040 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 SR |
1041 | } |
1042 | ||
1043 | /** | |
1044 | * update_max_tr_single - only copy one trace over, and reset the rest | |
1045 | * @tr - tracer | |
1046 | * @tsk - task with the latency | |
1047 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
1048 | * |
1049 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1050 | */ |
e309b41d | 1051 | void |
bc0c38d1 SR |
1052 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1053 | { | |
3928a8a2 | 1054 | int ret; |
bc0c38d1 | 1055 | |
2b6080f2 | 1056 | if (tr->stop_count) |
b8de7bd1 SR |
1057 | return; |
1058 | ||
4c11d7ae | 1059 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1060 | if (!tr->allocated_snapshot) { |
2930e04d | 1061 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1062 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1063 | return; |
2930e04d | 1064 | } |
ef710e10 | 1065 | |
0b9b12c1 | 1066 | arch_spin_lock(&tr->max_lock); |
bc0c38d1 | 1067 | |
12883efb | 1068 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 1069 | |
e8165dbb SR |
1070 | if (ret == -EBUSY) { |
1071 | /* | |
1072 | * We failed to swap the buffer due to a commit taking | |
1073 | * place on this CPU. We fail to record, but we reset | |
1074 | * the max trace buffer (no one writes directly to it) | |
1075 | * and flag that it failed. | |
1076 | */ | |
12883efb | 1077 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1078 | "Failed to swap buffers due to commit in progress\n"); |
1079 | } | |
1080 | ||
e8165dbb | 1081 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1082 | |
1083 | __update_max_tr(tr, tsk, cpu); | |
0b9b12c1 | 1084 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 | 1085 | } |
5d4a9dba | 1086 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1087 | |
b1169cc6 | 1088 | static void wait_on_pipe(struct trace_iterator *iter) |
0d5c6e1c | 1089 | { |
15693458 SRRH |
1090 | /* Iterators are static, they should be filled or empty */ |
1091 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
1092 | return; | |
0d5c6e1c | 1093 | |
12883efb | 1094 | ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file); |
0d5c6e1c SR |
1095 | } |
1096 | ||
f4e781c0 SRRH |
1097 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
1098 | static int run_tracer_selftest(struct tracer *type) | |
1099 | { | |
1100 | struct trace_array *tr = &global_trace; | |
1101 | struct tracer *saved_tracer = tr->current_trace; | |
1102 | int ret; | |
0d5c6e1c | 1103 | |
f4e781c0 SRRH |
1104 | if (!type->selftest || tracing_selftest_disabled) |
1105 | return 0; | |
0d5c6e1c SR |
1106 | |
1107 | /* | |
f4e781c0 SRRH |
1108 | * Run a selftest on this tracer. |
1109 | * Here we reset the trace buffer, and set the current | |
1110 | * tracer to be this tracer. The tracer can then run some | |
1111 | * internal tracing to verify that everything is in order. | |
1112 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1113 | */ |
f4e781c0 | 1114 | tracing_reset_online_cpus(&tr->trace_buffer); |
0d5c6e1c | 1115 | |
f4e781c0 SRRH |
1116 | tr->current_trace = type; |
1117 | ||
1118 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1119 | if (type->use_max_tr) { | |
1120 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1121 | if (ring_buffer_expanded) | |
1122 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1123 | RING_BUFFER_ALL_CPUS); | |
1124 | tr->allocated_snapshot = true; | |
1125 | } | |
1126 | #endif | |
1127 | ||
1128 | /* the test is responsible for initializing and enabling */ | |
1129 | pr_info("Testing tracer %s: ", type->name); | |
1130 | ret = type->selftest(type, tr); | |
1131 | /* the test is responsible for resetting too */ | |
1132 | tr->current_trace = saved_tracer; | |
1133 | if (ret) { | |
1134 | printk(KERN_CONT "FAILED!\n"); | |
1135 | /* Add the warning after printing 'FAILED' */ | |
1136 | WARN_ON(1); | |
1137 | return -1; | |
1138 | } | |
1139 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1140 | tracing_reset_online_cpus(&tr->trace_buffer); | |
1141 | ||
1142 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1143 | if (type->use_max_tr) { | |
1144 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1145 | |
f4e781c0 SRRH |
1146 | /* Shrink the max buffer again */ |
1147 | if (ring_buffer_expanded) | |
1148 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1149 | RING_BUFFER_ALL_CPUS); | |
1150 | } | |
1151 | #endif | |
1152 | ||
1153 | printk(KERN_CONT "PASSED\n"); | |
1154 | return 0; | |
1155 | } | |
1156 | #else | |
1157 | static inline int run_tracer_selftest(struct tracer *type) | |
1158 | { | |
1159 | return 0; | |
0d5c6e1c | 1160 | } |
f4e781c0 | 1161 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 1162 | |
4fcdae83 SR |
1163 | /** |
1164 | * register_tracer - register a tracer with the ftrace system. | |
1165 | * @type - the plugin for the tracer | |
1166 | * | |
1167 | * Register a new plugin tracer. | |
1168 | */ | |
bc0c38d1 SR |
1169 | int register_tracer(struct tracer *type) |
1170 | { | |
1171 | struct tracer *t; | |
bc0c38d1 SR |
1172 | int ret = 0; |
1173 | ||
1174 | if (!type->name) { | |
1175 | pr_info("Tracer must have a name\n"); | |
1176 | return -1; | |
1177 | } | |
1178 | ||
24a461d5 | 1179 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
1180 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
1181 | return -1; | |
1182 | } | |
1183 | ||
bc0c38d1 | 1184 | mutex_lock(&trace_types_lock); |
86fa2f60 | 1185 | |
8e1b82e0 FW |
1186 | tracing_selftest_running = true; |
1187 | ||
bc0c38d1 SR |
1188 | for (t = trace_types; t; t = t->next) { |
1189 | if (strcmp(type->name, t->name) == 0) { | |
1190 | /* already found */ | |
ee6c2c1b | 1191 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
1192 | type->name); |
1193 | ret = -1; | |
1194 | goto out; | |
1195 | } | |
1196 | } | |
1197 | ||
adf9f195 FW |
1198 | if (!type->set_flag) |
1199 | type->set_flag = &dummy_set_flag; | |
1200 | if (!type->flags) | |
1201 | type->flags = &dummy_tracer_flags; | |
1202 | else | |
1203 | if (!type->flags->opts) | |
1204 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 | 1205 | |
f4e781c0 SRRH |
1206 | ret = run_tracer_selftest(type); |
1207 | if (ret < 0) | |
1208 | goto out; | |
60a11774 | 1209 | |
bc0c38d1 SR |
1210 | type->next = trace_types; |
1211 | trace_types = type; | |
60a11774 | 1212 | |
bc0c38d1 | 1213 | out: |
8e1b82e0 | 1214 | tracing_selftest_running = false; |
bc0c38d1 SR |
1215 | mutex_unlock(&trace_types_lock); |
1216 | ||
dac74940 SR |
1217 | if (ret || !default_bootup_tracer) |
1218 | goto out_unlock; | |
1219 | ||
ee6c2c1b | 1220 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1221 | goto out_unlock; |
1222 | ||
1223 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1224 | /* Do we want this tracer to start on bootup? */ | |
607e2ea1 | 1225 | tracing_set_tracer(&global_trace, type->name); |
dac74940 SR |
1226 | default_bootup_tracer = NULL; |
1227 | /* disable other selftests, since this will break it. */ | |
55034cd6 | 1228 | tracing_selftest_disabled = true; |
b2821ae6 | 1229 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1230 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1231 | type->name); | |
b2821ae6 | 1232 | #endif |
b2821ae6 | 1233 | |
dac74940 | 1234 | out_unlock: |
bc0c38d1 SR |
1235 | return ret; |
1236 | } | |
1237 | ||
12883efb | 1238 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1239 | { |
12883efb | 1240 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1241 | |
a5416411 HT |
1242 | if (!buffer) |
1243 | return; | |
1244 | ||
f633903a SR |
1245 | ring_buffer_record_disable(buffer); |
1246 | ||
1247 | /* Make sure all commits have finished */ | |
1248 | synchronize_sched(); | |
68179686 | 1249 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1250 | |
1251 | ring_buffer_record_enable(buffer); | |
1252 | } | |
1253 | ||
12883efb | 1254 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1255 | { |
12883efb | 1256 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1257 | int cpu; |
1258 | ||
a5416411 HT |
1259 | if (!buffer) |
1260 | return; | |
1261 | ||
621968cd SR |
1262 | ring_buffer_record_disable(buffer); |
1263 | ||
1264 | /* Make sure all commits have finished */ | |
1265 | synchronize_sched(); | |
1266 | ||
9457158b | 1267 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 PE |
1268 | |
1269 | for_each_online_cpu(cpu) | |
68179686 | 1270 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1271 | |
1272 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1273 | } |
1274 | ||
09d8091c | 1275 | /* Must have trace_types_lock held */ |
873c642f | 1276 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1277 | { |
873c642f SRRH |
1278 | struct trace_array *tr; |
1279 | ||
873c642f | 1280 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
12883efb SRRH |
1281 | tracing_reset_online_cpus(&tr->trace_buffer); |
1282 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1283 | tracing_reset_online_cpus(&tr->max_buffer); | |
1284 | #endif | |
873c642f | 1285 | } |
9456f0fa SR |
1286 | } |
1287 | ||
bc0c38d1 | 1288 | #define SAVED_CMDLINES 128 |
2c7eea4c | 1289 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
1290 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
1291 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
1292 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
1293 | static int cmdline_idx; | |
edc35bd7 | 1294 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 1295 | |
25b0b44a | 1296 | /* temporary disable recording */ |
4fd27358 | 1297 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
1298 | |
1299 | static void trace_init_cmdlines(void) | |
1300 | { | |
2c7eea4c TG |
1301 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
1302 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
1303 | cmdline_idx = 0; |
1304 | } | |
1305 | ||
b5130b1e CE |
1306 | int is_tracing_stopped(void) |
1307 | { | |
2b6080f2 | 1308 | return global_trace.stop_count; |
b5130b1e CE |
1309 | } |
1310 | ||
0f048701 SR |
1311 | /** |
1312 | * tracing_start - quick start of the tracer | |
1313 | * | |
1314 | * If tracing is enabled but was stopped by tracing_stop, | |
1315 | * this will start the tracer back up. | |
1316 | */ | |
1317 | void tracing_start(void) | |
1318 | { | |
1319 | struct ring_buffer *buffer; | |
1320 | unsigned long flags; | |
1321 | ||
1322 | if (tracing_disabled) | |
1323 | return; | |
1324 | ||
2b6080f2 SR |
1325 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1326 | if (--global_trace.stop_count) { | |
1327 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1328 | /* Someone screwed up their debugging */ |
1329 | WARN_ON_ONCE(1); | |
2b6080f2 | 1330 | global_trace.stop_count = 0; |
b06a8301 | 1331 | } |
0f048701 SR |
1332 | goto out; |
1333 | } | |
1334 | ||
a2f80714 | 1335 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1336 | arch_spin_lock(&global_trace.max_lock); |
0f048701 | 1337 | |
12883efb | 1338 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1339 | if (buffer) |
1340 | ring_buffer_record_enable(buffer); | |
1341 | ||
12883efb SRRH |
1342 | #ifdef CONFIG_TRACER_MAX_TRACE |
1343 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1344 | if (buffer) |
1345 | ring_buffer_record_enable(buffer); | |
12883efb | 1346 | #endif |
0f048701 | 1347 | |
0b9b12c1 | 1348 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1349 | |
0f048701 SR |
1350 | ftrace_start(); |
1351 | out: | |
2b6080f2 SR |
1352 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1353 | } | |
1354 | ||
1355 | static void tracing_start_tr(struct trace_array *tr) | |
1356 | { | |
1357 | struct ring_buffer *buffer; | |
1358 | unsigned long flags; | |
1359 | ||
1360 | if (tracing_disabled) | |
1361 | return; | |
1362 | ||
1363 | /* If global, we need to also start the max tracer */ | |
1364 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1365 | return tracing_start(); | |
1366 | ||
1367 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1368 | ||
1369 | if (--tr->stop_count) { | |
1370 | if (tr->stop_count < 0) { | |
1371 | /* Someone screwed up their debugging */ | |
1372 | WARN_ON_ONCE(1); | |
1373 | tr->stop_count = 0; | |
1374 | } | |
1375 | goto out; | |
1376 | } | |
1377 | ||
12883efb | 1378 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1379 | if (buffer) |
1380 | ring_buffer_record_enable(buffer); | |
1381 | ||
1382 | out: | |
1383 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1384 | } |
1385 | ||
1386 | /** | |
1387 | * tracing_stop - quick stop of the tracer | |
1388 | * | |
1389 | * Light weight way to stop tracing. Use in conjunction with | |
1390 | * tracing_start. | |
1391 | */ | |
1392 | void tracing_stop(void) | |
1393 | { | |
1394 | struct ring_buffer *buffer; | |
1395 | unsigned long flags; | |
1396 | ||
1397 | ftrace_stop(); | |
2b6080f2 SR |
1398 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1399 | if (global_trace.stop_count++) | |
0f048701 SR |
1400 | goto out; |
1401 | ||
a2f80714 | 1402 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1403 | arch_spin_lock(&global_trace.max_lock); |
a2f80714 | 1404 | |
12883efb | 1405 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1406 | if (buffer) |
1407 | ring_buffer_record_disable(buffer); | |
1408 | ||
12883efb SRRH |
1409 | #ifdef CONFIG_TRACER_MAX_TRACE |
1410 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1411 | if (buffer) |
1412 | ring_buffer_record_disable(buffer); | |
12883efb | 1413 | #endif |
0f048701 | 1414 | |
0b9b12c1 | 1415 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1416 | |
0f048701 | 1417 | out: |
2b6080f2 SR |
1418 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1419 | } | |
1420 | ||
1421 | static void tracing_stop_tr(struct trace_array *tr) | |
1422 | { | |
1423 | struct ring_buffer *buffer; | |
1424 | unsigned long flags; | |
1425 | ||
1426 | /* If global, we need to also stop the max tracer */ | |
1427 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1428 | return tracing_stop(); | |
1429 | ||
1430 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1431 | if (tr->stop_count++) | |
1432 | goto out; | |
1433 | ||
12883efb | 1434 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1435 | if (buffer) |
1436 | ring_buffer_record_disable(buffer); | |
1437 | ||
1438 | out: | |
1439 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1440 | } |
1441 | ||
e309b41d | 1442 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1443 | |
379cfdac | 1444 | static int trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1445 | { |
a635cf04 | 1446 | unsigned pid, idx; |
bc0c38d1 SR |
1447 | |
1448 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
379cfdac | 1449 | return 0; |
bc0c38d1 SR |
1450 | |
1451 | /* | |
1452 | * It's not the end of the world if we don't get | |
1453 | * the lock, but we also don't want to spin | |
1454 | * nor do we want to disable interrupts, | |
1455 | * so if we miss here, then better luck next time. | |
1456 | */ | |
0199c4e6 | 1457 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
379cfdac | 1458 | return 0; |
bc0c38d1 SR |
1459 | |
1460 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1461 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1462 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1463 | ||
a635cf04 CE |
1464 | /* |
1465 | * Check whether the cmdline buffer at idx has a pid | |
1466 | * mapped. We are going to overwrite that entry so we | |
1467 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1468 | * would read the new comm for the old pid. | |
1469 | */ | |
1470 | pid = map_cmdline_to_pid[idx]; | |
1471 | if (pid != NO_CMDLINE_MAP) | |
1472 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1473 | |
a635cf04 | 1474 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1475 | map_pid_to_cmdline[tsk->pid] = idx; |
1476 | ||
1477 | cmdline_idx = idx; | |
1478 | } | |
1479 | ||
1480 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1481 | ||
0199c4e6 | 1482 | arch_spin_unlock(&trace_cmdline_lock); |
379cfdac SRRH |
1483 | |
1484 | return 1; | |
bc0c38d1 SR |
1485 | } |
1486 | ||
4c27e756 | 1487 | static void __trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1488 | { |
bc0c38d1 SR |
1489 | unsigned map; |
1490 | ||
4ca53085 SR |
1491 | if (!pid) { |
1492 | strcpy(comm, "<idle>"); | |
1493 | return; | |
1494 | } | |
bc0c38d1 | 1495 | |
74bf4076 SR |
1496 | if (WARN_ON_ONCE(pid < 0)) { |
1497 | strcpy(comm, "<XXX>"); | |
1498 | return; | |
1499 | } | |
1500 | ||
4ca53085 SR |
1501 | if (pid > PID_MAX_DEFAULT) { |
1502 | strcpy(comm, "<...>"); | |
1503 | return; | |
1504 | } | |
bc0c38d1 SR |
1505 | |
1506 | map = map_pid_to_cmdline[pid]; | |
50d88758 TG |
1507 | if (map != NO_CMDLINE_MAP) |
1508 | strcpy(comm, saved_cmdlines[map]); | |
1509 | else | |
1510 | strcpy(comm, "<...>"); | |
4c27e756 SRRH |
1511 | } |
1512 | ||
1513 | void trace_find_cmdline(int pid, char comm[]) | |
1514 | { | |
1515 | preempt_disable(); | |
1516 | arch_spin_lock(&trace_cmdline_lock); | |
1517 | ||
1518 | __trace_find_cmdline(pid, comm); | |
bc0c38d1 | 1519 | |
0199c4e6 | 1520 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1521 | preempt_enable(); |
bc0c38d1 SR |
1522 | } |
1523 | ||
e309b41d | 1524 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1525 | { |
0fb9656d | 1526 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1527 | return; |
1528 | ||
7ffbd48d SR |
1529 | if (!__this_cpu_read(trace_cmdline_save)) |
1530 | return; | |
1531 | ||
379cfdac SRRH |
1532 | if (trace_save_cmdline(tsk)) |
1533 | __this_cpu_write(trace_cmdline_save, false); | |
bc0c38d1 SR |
1534 | } |
1535 | ||
45dcd8b8 | 1536 | void |
38697053 SR |
1537 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1538 | int pc) | |
bc0c38d1 SR |
1539 | { |
1540 | struct task_struct *tsk = current; | |
bc0c38d1 | 1541 | |
777e208d SR |
1542 | entry->preempt_count = pc & 0xff; |
1543 | entry->pid = (tsk) ? tsk->pid : 0; | |
1544 | entry->flags = | |
9244489a | 1545 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1546 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1547 | #else |
1548 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1549 | #endif | |
bc0c38d1 SR |
1550 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1551 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
e5137b50 PZ |
1552 | (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) | |
1553 | (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0); | |
bc0c38d1 | 1554 | } |
f413cdb8 | 1555 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1556 | |
e77405ad SR |
1557 | struct ring_buffer_event * |
1558 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1559 | int type, | |
1560 | unsigned long len, | |
1561 | unsigned long flags, int pc) | |
51a763dd ACM |
1562 | { |
1563 | struct ring_buffer_event *event; | |
1564 | ||
e77405ad | 1565 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1566 | if (event != NULL) { |
1567 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1568 | ||
1569 | tracing_generic_entry_update(ent, flags, pc); | |
1570 | ent->type = type; | |
1571 | } | |
1572 | ||
1573 | return event; | |
1574 | } | |
51a763dd | 1575 | |
7ffbd48d SR |
1576 | void |
1577 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1578 | { | |
1579 | __this_cpu_write(trace_cmdline_save, true); | |
1580 | ring_buffer_unlock_commit(buffer, event); | |
1581 | } | |
1582 | ||
e77405ad SR |
1583 | static inline void |
1584 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1585 | struct ring_buffer_event *event, | |
0d5c6e1c | 1586 | unsigned long flags, int pc) |
51a763dd | 1587 | { |
7ffbd48d | 1588 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1589 | |
e77405ad SR |
1590 | ftrace_trace_stack(buffer, flags, 6, pc); |
1591 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1592 | } |
1593 | ||
e77405ad SR |
1594 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1595 | struct ring_buffer_event *event, | |
1596 | unsigned long flags, int pc) | |
07edf712 | 1597 | { |
0d5c6e1c | 1598 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
51a763dd | 1599 | } |
0d5c6e1c | 1600 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1601 | |
2c4a33ab SRRH |
1602 | static struct ring_buffer *temp_buffer; |
1603 | ||
ccb469a1 SR |
1604 | struct ring_buffer_event * |
1605 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
1606 | struct ftrace_event_file *ftrace_file, | |
1607 | int type, unsigned long len, | |
1608 | unsigned long flags, int pc) | |
1609 | { | |
2c4a33ab SRRH |
1610 | struct ring_buffer_event *entry; |
1611 | ||
12883efb | 1612 | *current_rb = ftrace_file->tr->trace_buffer.buffer; |
2c4a33ab | 1613 | entry = trace_buffer_lock_reserve(*current_rb, |
ccb469a1 | 1614 | type, len, flags, pc); |
2c4a33ab SRRH |
1615 | /* |
1616 | * If tracing is off, but we have triggers enabled | |
1617 | * we still need to look at the event data. Use the temp_buffer | |
1618 | * to store the trace event for the tigger to use. It's recusive | |
1619 | * safe and will not be recorded anywhere. | |
1620 | */ | |
1621 | if (!entry && ftrace_file->flags & FTRACE_EVENT_FL_TRIGGER_COND) { | |
1622 | *current_rb = temp_buffer; | |
1623 | entry = trace_buffer_lock_reserve(*current_rb, | |
1624 | type, len, flags, pc); | |
1625 | } | |
1626 | return entry; | |
ccb469a1 SR |
1627 | } |
1628 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
1629 | ||
ef5580d0 | 1630 | struct ring_buffer_event * |
e77405ad SR |
1631 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1632 | int type, unsigned long len, | |
ef5580d0 SR |
1633 | unsigned long flags, int pc) |
1634 | { | |
12883efb | 1635 | *current_rb = global_trace.trace_buffer.buffer; |
e77405ad | 1636 | return trace_buffer_lock_reserve(*current_rb, |
ef5580d0 SR |
1637 | type, len, flags, pc); |
1638 | } | |
94487d6d | 1639 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1640 | |
e77405ad SR |
1641 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1642 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1643 | unsigned long flags, int pc) |
1644 | { | |
0d5c6e1c | 1645 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
07edf712 | 1646 | } |
94487d6d | 1647 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1648 | |
0d5c6e1c SR |
1649 | void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1650 | struct ring_buffer_event *event, | |
1651 | unsigned long flags, int pc, | |
1652 | struct pt_regs *regs) | |
1fd8df2c | 1653 | { |
7ffbd48d | 1654 | __buffer_unlock_commit(buffer, event); |
1fd8df2c MH |
1655 | |
1656 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1657 | ftrace_trace_userstack(buffer, flags, pc); | |
1658 | } | |
0d5c6e1c | 1659 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1660 | |
e77405ad SR |
1661 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1662 | struct ring_buffer_event *event) | |
77d9f465 | 1663 | { |
e77405ad | 1664 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1665 | } |
12acd473 | 1666 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1667 | |
e309b41d | 1668 | void |
7be42151 | 1669 | trace_function(struct trace_array *tr, |
38697053 SR |
1670 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1671 | int pc) | |
bc0c38d1 | 1672 | { |
e1112b4d | 1673 | struct ftrace_event_call *call = &event_function; |
12883efb | 1674 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 1675 | struct ring_buffer_event *event; |
777e208d | 1676 | struct ftrace_entry *entry; |
bc0c38d1 | 1677 | |
d769041f | 1678 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1679 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1680 | return; |
1681 | ||
e77405ad | 1682 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1683 | flags, pc); |
3928a8a2 SR |
1684 | if (!event) |
1685 | return; | |
1686 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1687 | entry->ip = ip; |
1688 | entry->parent_ip = parent_ip; | |
e1112b4d | 1689 | |
f306cc82 | 1690 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1691 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1692 | } |
1693 | ||
c0a0d0d3 | 1694 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1695 | |
1696 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1697 | struct ftrace_stack { | |
1698 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1699 | }; | |
1700 | ||
1701 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1702 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1703 | ||
e77405ad | 1704 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1705 | unsigned long flags, |
1fd8df2c | 1706 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1707 | { |
e1112b4d | 1708 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1709 | struct ring_buffer_event *event; |
777e208d | 1710 | struct stack_entry *entry; |
86387f7e | 1711 | struct stack_trace trace; |
4a9bd3f1 SR |
1712 | int use_stack; |
1713 | int size = FTRACE_STACK_ENTRIES; | |
1714 | ||
1715 | trace.nr_entries = 0; | |
1716 | trace.skip = skip; | |
1717 | ||
1718 | /* | |
1719 | * Since events can happen in NMIs there's no safe way to | |
1720 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1721 | * or NMI comes in, it will just have to use the default | |
1722 | * FTRACE_STACK_SIZE. | |
1723 | */ | |
1724 | preempt_disable_notrace(); | |
1725 | ||
82146529 | 1726 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
1727 | /* |
1728 | * We don't need any atomic variables, just a barrier. | |
1729 | * If an interrupt comes in, we don't care, because it would | |
1730 | * have exited and put the counter back to what we want. | |
1731 | * We just need a barrier to keep gcc from moving things | |
1732 | * around. | |
1733 | */ | |
1734 | barrier(); | |
1735 | if (use_stack == 1) { | |
bdffd893 | 1736 | trace.entries = this_cpu_ptr(ftrace_stack.calls); |
4a9bd3f1 SR |
1737 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; |
1738 | ||
1739 | if (regs) | |
1740 | save_stack_trace_regs(regs, &trace); | |
1741 | else | |
1742 | save_stack_trace(&trace); | |
1743 | ||
1744 | if (trace.nr_entries > size) | |
1745 | size = trace.nr_entries; | |
1746 | } else | |
1747 | /* From now on, use_stack is a boolean */ | |
1748 | use_stack = 0; | |
1749 | ||
1750 | size *= sizeof(unsigned long); | |
86387f7e | 1751 | |
e77405ad | 1752 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1753 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1754 | if (!event) |
4a9bd3f1 SR |
1755 | goto out; |
1756 | entry = ring_buffer_event_data(event); | |
86387f7e | 1757 | |
4a9bd3f1 SR |
1758 | memset(&entry->caller, 0, size); |
1759 | ||
1760 | if (use_stack) | |
1761 | memcpy(&entry->caller, trace.entries, | |
1762 | trace.nr_entries * sizeof(unsigned long)); | |
1763 | else { | |
1764 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1765 | trace.entries = entry->caller; | |
1766 | if (regs) | |
1767 | save_stack_trace_regs(regs, &trace); | |
1768 | else | |
1769 | save_stack_trace(&trace); | |
1770 | } | |
1771 | ||
1772 | entry->size = trace.nr_entries; | |
86387f7e | 1773 | |
f306cc82 | 1774 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1775 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1776 | |
1777 | out: | |
1778 | /* Again, don't let gcc optimize things here */ | |
1779 | barrier(); | |
82146529 | 1780 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
1781 | preempt_enable_notrace(); |
1782 | ||
f0a920d5 IM |
1783 | } |
1784 | ||
1fd8df2c MH |
1785 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1786 | int skip, int pc, struct pt_regs *regs) | |
1787 | { | |
1788 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1789 | return; | |
1790 | ||
1791 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1792 | } | |
1793 | ||
e77405ad SR |
1794 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1795 | int skip, int pc) | |
53614991 SR |
1796 | { |
1797 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1798 | return; | |
1799 | ||
1fd8df2c | 1800 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1801 | } |
1802 | ||
c0a0d0d3 FW |
1803 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1804 | int pc) | |
38697053 | 1805 | { |
12883efb | 1806 | __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); |
38697053 SR |
1807 | } |
1808 | ||
03889384 SR |
1809 | /** |
1810 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 1811 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 1812 | */ |
c142be8e | 1813 | void trace_dump_stack(int skip) |
03889384 SR |
1814 | { |
1815 | unsigned long flags; | |
1816 | ||
1817 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1818 | return; |
03889384 SR |
1819 | |
1820 | local_save_flags(flags); | |
1821 | ||
c142be8e SRRH |
1822 | /* |
1823 | * Skip 3 more, seems to get us at the caller of | |
1824 | * this function. | |
1825 | */ | |
1826 | skip += 3; | |
1827 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, | |
1828 | flags, skip, preempt_count(), NULL); | |
03889384 SR |
1829 | } |
1830 | ||
91e86e56 SR |
1831 | static DEFINE_PER_CPU(int, user_stack_count); |
1832 | ||
e77405ad SR |
1833 | void |
1834 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1835 | { |
e1112b4d | 1836 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1837 | struct ring_buffer_event *event; |
02b67518 TE |
1838 | struct userstack_entry *entry; |
1839 | struct stack_trace trace; | |
02b67518 TE |
1840 | |
1841 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1842 | return; | |
1843 | ||
b6345879 SR |
1844 | /* |
1845 | * NMIs can not handle page faults, even with fix ups. | |
1846 | * The save user stack can (and often does) fault. | |
1847 | */ | |
1848 | if (unlikely(in_nmi())) | |
1849 | return; | |
02b67518 | 1850 | |
91e86e56 SR |
1851 | /* |
1852 | * prevent recursion, since the user stack tracing may | |
1853 | * trigger other kernel events. | |
1854 | */ | |
1855 | preempt_disable(); | |
1856 | if (__this_cpu_read(user_stack_count)) | |
1857 | goto out; | |
1858 | ||
1859 | __this_cpu_inc(user_stack_count); | |
1860 | ||
e77405ad | 1861 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1862 | sizeof(*entry), flags, pc); |
02b67518 | 1863 | if (!event) |
1dbd1951 | 1864 | goto out_drop_count; |
02b67518 | 1865 | entry = ring_buffer_event_data(event); |
02b67518 | 1866 | |
48659d31 | 1867 | entry->tgid = current->tgid; |
02b67518 TE |
1868 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1869 | ||
1870 | trace.nr_entries = 0; | |
1871 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1872 | trace.skip = 0; | |
1873 | trace.entries = entry->caller; | |
1874 | ||
1875 | save_stack_trace_user(&trace); | |
f306cc82 | 1876 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1877 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1878 | |
1dbd1951 | 1879 | out_drop_count: |
91e86e56 | 1880 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1881 | out: |
1882 | preempt_enable(); | |
02b67518 TE |
1883 | } |
1884 | ||
4fd27358 HE |
1885 | #ifdef UNUSED |
1886 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1887 | { |
7be42151 | 1888 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1889 | } |
4fd27358 | 1890 | #endif /* UNUSED */ |
02b67518 | 1891 | |
c0a0d0d3 FW |
1892 | #endif /* CONFIG_STACKTRACE */ |
1893 | ||
07d777fe SR |
1894 | /* created for use with alloc_percpu */ |
1895 | struct trace_buffer_struct { | |
1896 | char buffer[TRACE_BUF_SIZE]; | |
1897 | }; | |
1898 | ||
1899 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1900 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1901 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1902 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1903 | ||
1904 | /* | |
1905 | * The buffer used is dependent on the context. There is a per cpu | |
1906 | * buffer for normal context, softirq contex, hard irq context and | |
1907 | * for NMI context. Thise allows for lockless recording. | |
1908 | * | |
1909 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1910 | */ | |
1911 | static char *get_trace_buf(void) | |
1912 | { | |
1913 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
1914 | |
1915 | /* | |
1916 | * If we have allocated per cpu buffers, then we do not | |
1917 | * need to do any locking. | |
1918 | */ | |
1919 | if (in_nmi()) | |
1920 | percpu_buffer = trace_percpu_nmi_buffer; | |
1921 | else if (in_irq()) | |
1922 | percpu_buffer = trace_percpu_irq_buffer; | |
1923 | else if (in_softirq()) | |
1924 | percpu_buffer = trace_percpu_sirq_buffer; | |
1925 | else | |
1926 | percpu_buffer = trace_percpu_buffer; | |
1927 | ||
1928 | if (!percpu_buffer) | |
1929 | return NULL; | |
1930 | ||
d8a0349c | 1931 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
1932 | } |
1933 | ||
1934 | static int alloc_percpu_trace_buffer(void) | |
1935 | { | |
1936 | struct trace_buffer_struct *buffers; | |
1937 | struct trace_buffer_struct *sirq_buffers; | |
1938 | struct trace_buffer_struct *irq_buffers; | |
1939 | struct trace_buffer_struct *nmi_buffers; | |
1940 | ||
1941 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1942 | if (!buffers) | |
1943 | goto err_warn; | |
1944 | ||
1945 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1946 | if (!sirq_buffers) | |
1947 | goto err_sirq; | |
1948 | ||
1949 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1950 | if (!irq_buffers) | |
1951 | goto err_irq; | |
1952 | ||
1953 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
1954 | if (!nmi_buffers) | |
1955 | goto err_nmi; | |
1956 | ||
1957 | trace_percpu_buffer = buffers; | |
1958 | trace_percpu_sirq_buffer = sirq_buffers; | |
1959 | trace_percpu_irq_buffer = irq_buffers; | |
1960 | trace_percpu_nmi_buffer = nmi_buffers; | |
1961 | ||
1962 | return 0; | |
1963 | ||
1964 | err_nmi: | |
1965 | free_percpu(irq_buffers); | |
1966 | err_irq: | |
1967 | free_percpu(sirq_buffers); | |
1968 | err_sirq: | |
1969 | free_percpu(buffers); | |
1970 | err_warn: | |
1971 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
1972 | return -ENOMEM; | |
1973 | } | |
1974 | ||
81698831 SR |
1975 | static int buffers_allocated; |
1976 | ||
07d777fe SR |
1977 | void trace_printk_init_buffers(void) |
1978 | { | |
07d777fe SR |
1979 | if (buffers_allocated) |
1980 | return; | |
1981 | ||
1982 | if (alloc_percpu_trace_buffer()) | |
1983 | return; | |
1984 | ||
2184db46 SR |
1985 | /* trace_printk() is for debug use only. Don't use it in production. */ |
1986 | ||
1987 | pr_warning("\n**********************************************************\n"); | |
1988 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
1989 | pr_warning("** **\n"); | |
1990 | pr_warning("** trace_printk() being used. Allocating extra memory. **\n"); | |
1991 | pr_warning("** **\n"); | |
1992 | pr_warning("** This means that this is a DEBUG kernel and it is **\n"); | |
1993 | pr_warning("** unsafe for produciton use. **\n"); | |
1994 | pr_warning("** **\n"); | |
1995 | pr_warning("** If you see this message and you are not debugging **\n"); | |
1996 | pr_warning("** the kernel, report this immediately to your vendor! **\n"); | |
1997 | pr_warning("** **\n"); | |
1998 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
1999 | pr_warning("**********************************************************\n"); | |
07d777fe | 2000 | |
b382ede6 SR |
2001 | /* Expand the buffers to set size */ |
2002 | tracing_update_buffers(); | |
2003 | ||
07d777fe | 2004 | buffers_allocated = 1; |
81698831 SR |
2005 | |
2006 | /* | |
2007 | * trace_printk_init_buffers() can be called by modules. | |
2008 | * If that happens, then we need to start cmdline recording | |
2009 | * directly here. If the global_trace.buffer is already | |
2010 | * allocated here, then this was called by module code. | |
2011 | */ | |
12883efb | 2012 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
2013 | tracing_start_cmdline_record(); |
2014 | } | |
2015 | ||
2016 | void trace_printk_start_comm(void) | |
2017 | { | |
2018 | /* Start tracing comms if trace printk is set */ | |
2019 | if (!buffers_allocated) | |
2020 | return; | |
2021 | tracing_start_cmdline_record(); | |
2022 | } | |
2023 | ||
2024 | static void trace_printk_start_stop_comm(int enabled) | |
2025 | { | |
2026 | if (!buffers_allocated) | |
2027 | return; | |
2028 | ||
2029 | if (enabled) | |
2030 | tracing_start_cmdline_record(); | |
2031 | else | |
2032 | tracing_stop_cmdline_record(); | |
07d777fe SR |
2033 | } |
2034 | ||
769b0441 | 2035 | /** |
48ead020 | 2036 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
2037 | * |
2038 | */ | |
40ce74f1 | 2039 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 2040 | { |
e1112b4d | 2041 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 2042 | struct ring_buffer_event *event; |
e77405ad | 2043 | struct ring_buffer *buffer; |
769b0441 | 2044 | struct trace_array *tr = &global_trace; |
48ead020 | 2045 | struct bprint_entry *entry; |
769b0441 | 2046 | unsigned long flags; |
07d777fe SR |
2047 | char *tbuffer; |
2048 | int len = 0, size, pc; | |
769b0441 FW |
2049 | |
2050 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
2051 | return 0; | |
2052 | ||
2053 | /* Don't pollute graph traces with trace_vprintk internals */ | |
2054 | pause_graph_tracing(); | |
2055 | ||
2056 | pc = preempt_count(); | |
5168ae50 | 2057 | preempt_disable_notrace(); |
769b0441 | 2058 | |
07d777fe SR |
2059 | tbuffer = get_trace_buf(); |
2060 | if (!tbuffer) { | |
2061 | len = 0; | |
769b0441 | 2062 | goto out; |
07d777fe | 2063 | } |
769b0441 | 2064 | |
07d777fe | 2065 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 2066 | |
07d777fe SR |
2067 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
2068 | goto out; | |
769b0441 | 2069 | |
07d777fe | 2070 | local_save_flags(flags); |
769b0441 | 2071 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 2072 | buffer = tr->trace_buffer.buffer; |
e77405ad SR |
2073 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
2074 | flags, pc); | |
769b0441 | 2075 | if (!event) |
07d777fe | 2076 | goto out; |
769b0441 FW |
2077 | entry = ring_buffer_event_data(event); |
2078 | entry->ip = ip; | |
769b0441 FW |
2079 | entry->fmt = fmt; |
2080 | ||
07d777fe | 2081 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
f306cc82 | 2082 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2083 | __buffer_unlock_commit(buffer, event); |
d931369b SR |
2084 | ftrace_trace_stack(buffer, flags, 6, pc); |
2085 | } | |
769b0441 | 2086 | |
769b0441 | 2087 | out: |
5168ae50 | 2088 | preempt_enable_notrace(); |
769b0441 FW |
2089 | unpause_graph_tracing(); |
2090 | ||
2091 | return len; | |
2092 | } | |
48ead020 FW |
2093 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
2094 | ||
12883efb SRRH |
2095 | static int |
2096 | __trace_array_vprintk(struct ring_buffer *buffer, | |
2097 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 2098 | { |
e1112b4d | 2099 | struct ftrace_event_call *call = &event_print; |
48ead020 | 2100 | struct ring_buffer_event *event; |
07d777fe | 2101 | int len = 0, size, pc; |
48ead020 | 2102 | struct print_entry *entry; |
07d777fe SR |
2103 | unsigned long flags; |
2104 | char *tbuffer; | |
48ead020 FW |
2105 | |
2106 | if (tracing_disabled || tracing_selftest_running) | |
2107 | return 0; | |
2108 | ||
07d777fe SR |
2109 | /* Don't pollute graph traces with trace_vprintk internals */ |
2110 | pause_graph_tracing(); | |
2111 | ||
48ead020 FW |
2112 | pc = preempt_count(); |
2113 | preempt_disable_notrace(); | |
48ead020 | 2114 | |
07d777fe SR |
2115 | |
2116 | tbuffer = get_trace_buf(); | |
2117 | if (!tbuffer) { | |
2118 | len = 0; | |
48ead020 | 2119 | goto out; |
07d777fe | 2120 | } |
48ead020 | 2121 | |
07d777fe SR |
2122 | len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
2123 | if (len > TRACE_BUF_SIZE) | |
2124 | goto out; | |
48ead020 | 2125 | |
07d777fe | 2126 | local_save_flags(flags); |
48ead020 | 2127 | size = sizeof(*entry) + len + 1; |
e77405ad | 2128 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
07d777fe | 2129 | flags, pc); |
48ead020 | 2130 | if (!event) |
07d777fe | 2131 | goto out; |
48ead020 | 2132 | entry = ring_buffer_event_data(event); |
c13d2f7c | 2133 | entry->ip = ip; |
48ead020 | 2134 | |
07d777fe | 2135 | memcpy(&entry->buf, tbuffer, len); |
c13d2f7c | 2136 | entry->buf[len] = '\0'; |
f306cc82 | 2137 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2138 | __buffer_unlock_commit(buffer, event); |
07d777fe | 2139 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 2140 | } |
48ead020 FW |
2141 | out: |
2142 | preempt_enable_notrace(); | |
07d777fe | 2143 | unpause_graph_tracing(); |
48ead020 FW |
2144 | |
2145 | return len; | |
2146 | } | |
659372d3 | 2147 | |
12883efb SRRH |
2148 | int trace_array_vprintk(struct trace_array *tr, |
2149 | unsigned long ip, const char *fmt, va_list args) | |
2150 | { | |
2151 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
2152 | } | |
2153 | ||
2154 | int trace_array_printk(struct trace_array *tr, | |
2155 | unsigned long ip, const char *fmt, ...) | |
2156 | { | |
2157 | int ret; | |
2158 | va_list ap; | |
2159 | ||
2160 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2161 | return 0; | |
2162 | ||
2163 | va_start(ap, fmt); | |
2164 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
2165 | va_end(ap); | |
2166 | return ret; | |
2167 | } | |
2168 | ||
2169 | int trace_array_printk_buf(struct ring_buffer *buffer, | |
2170 | unsigned long ip, const char *fmt, ...) | |
2171 | { | |
2172 | int ret; | |
2173 | va_list ap; | |
2174 | ||
2175 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2176 | return 0; | |
2177 | ||
2178 | va_start(ap, fmt); | |
2179 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
2180 | va_end(ap); | |
2181 | return ret; | |
2182 | } | |
2183 | ||
659372d3 SR |
2184 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
2185 | { | |
a813a159 | 2186 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 2187 | } |
769b0441 FW |
2188 | EXPORT_SYMBOL_GPL(trace_vprintk); |
2189 | ||
e2ac8ef5 | 2190 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 2191 | { |
6d158a81 SR |
2192 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
2193 | ||
5a90f577 | 2194 | iter->idx++; |
6d158a81 SR |
2195 | if (buf_iter) |
2196 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
2197 | } |
2198 | ||
e309b41d | 2199 | static struct trace_entry * |
bc21b478 SR |
2200 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
2201 | unsigned long *lost_events) | |
dd0e545f | 2202 | { |
3928a8a2 | 2203 | struct ring_buffer_event *event; |
6d158a81 | 2204 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 2205 | |
d769041f SR |
2206 | if (buf_iter) |
2207 | event = ring_buffer_iter_peek(buf_iter, ts); | |
2208 | else | |
12883efb | 2209 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 2210 | lost_events); |
d769041f | 2211 | |
4a9bd3f1 SR |
2212 | if (event) { |
2213 | iter->ent_size = ring_buffer_event_length(event); | |
2214 | return ring_buffer_event_data(event); | |
2215 | } | |
2216 | iter->ent_size = 0; | |
2217 | return NULL; | |
dd0e545f | 2218 | } |
d769041f | 2219 | |
dd0e545f | 2220 | static struct trace_entry * |
bc21b478 SR |
2221 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
2222 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 2223 | { |
12883efb | 2224 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 2225 | struct trace_entry *ent, *next = NULL; |
aa27497c | 2226 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 2227 | int cpu_file = iter->cpu_file; |
3928a8a2 | 2228 | u64 next_ts = 0, ts; |
bc0c38d1 | 2229 | int next_cpu = -1; |
12b5da34 | 2230 | int next_size = 0; |
bc0c38d1 SR |
2231 | int cpu; |
2232 | ||
b04cc6b1 FW |
2233 | /* |
2234 | * If we are in a per_cpu trace file, don't bother by iterating over | |
2235 | * all cpu and peek directly. | |
2236 | */ | |
ae3b5093 | 2237 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
2238 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
2239 | return NULL; | |
bc21b478 | 2240 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
2241 | if (ent_cpu) |
2242 | *ent_cpu = cpu_file; | |
2243 | ||
2244 | return ent; | |
2245 | } | |
2246 | ||
ab46428c | 2247 | for_each_tracing_cpu(cpu) { |
dd0e545f | 2248 | |
3928a8a2 SR |
2249 | if (ring_buffer_empty_cpu(buffer, cpu)) |
2250 | continue; | |
dd0e545f | 2251 | |
bc21b478 | 2252 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 2253 | |
cdd31cd2 IM |
2254 | /* |
2255 | * Pick the entry with the smallest timestamp: | |
2256 | */ | |
3928a8a2 | 2257 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
2258 | next = ent; |
2259 | next_cpu = cpu; | |
3928a8a2 | 2260 | next_ts = ts; |
bc21b478 | 2261 | next_lost = lost_events; |
12b5da34 | 2262 | next_size = iter->ent_size; |
bc0c38d1 SR |
2263 | } |
2264 | } | |
2265 | ||
12b5da34 SR |
2266 | iter->ent_size = next_size; |
2267 | ||
bc0c38d1 SR |
2268 | if (ent_cpu) |
2269 | *ent_cpu = next_cpu; | |
2270 | ||
3928a8a2 SR |
2271 | if (ent_ts) |
2272 | *ent_ts = next_ts; | |
2273 | ||
bc21b478 SR |
2274 | if (missing_events) |
2275 | *missing_events = next_lost; | |
2276 | ||
bc0c38d1 SR |
2277 | return next; |
2278 | } | |
2279 | ||
dd0e545f | 2280 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
2281 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
2282 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 2283 | { |
bc21b478 | 2284 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
2285 | } |
2286 | ||
2287 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 2288 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 2289 | { |
bc21b478 SR |
2290 | iter->ent = __find_next_entry(iter, &iter->cpu, |
2291 | &iter->lost_events, &iter->ts); | |
dd0e545f | 2292 | |
3928a8a2 | 2293 | if (iter->ent) |
e2ac8ef5 | 2294 | trace_iterator_increment(iter); |
dd0e545f | 2295 | |
3928a8a2 | 2296 | return iter->ent ? iter : NULL; |
b3806b43 | 2297 | } |
bc0c38d1 | 2298 | |
e309b41d | 2299 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 2300 | { |
12883efb | 2301 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 2302 | &iter->lost_events); |
bc0c38d1 SR |
2303 | } |
2304 | ||
e309b41d | 2305 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
2306 | { |
2307 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 2308 | int i = (int)*pos; |
4e3c3333 | 2309 | void *ent; |
bc0c38d1 | 2310 | |
a63ce5b3 SR |
2311 | WARN_ON_ONCE(iter->leftover); |
2312 | ||
bc0c38d1 SR |
2313 | (*pos)++; |
2314 | ||
2315 | /* can't go backwards */ | |
2316 | if (iter->idx > i) | |
2317 | return NULL; | |
2318 | ||
2319 | if (iter->idx < 0) | |
955b61e5 | 2320 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2321 | else |
2322 | ent = iter; | |
2323 | ||
2324 | while (ent && iter->idx < i) | |
955b61e5 | 2325 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2326 | |
2327 | iter->pos = *pos; | |
2328 | ||
bc0c38d1 SR |
2329 | return ent; |
2330 | } | |
2331 | ||
955b61e5 | 2332 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 2333 | { |
2f26ebd5 SR |
2334 | struct ring_buffer_event *event; |
2335 | struct ring_buffer_iter *buf_iter; | |
2336 | unsigned long entries = 0; | |
2337 | u64 ts; | |
2338 | ||
12883efb | 2339 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 2340 | |
6d158a81 SR |
2341 | buf_iter = trace_buffer_iter(iter, cpu); |
2342 | if (!buf_iter) | |
2f26ebd5 SR |
2343 | return; |
2344 | ||
2f26ebd5 SR |
2345 | ring_buffer_iter_reset(buf_iter); |
2346 | ||
2347 | /* | |
2348 | * We could have the case with the max latency tracers | |
2349 | * that a reset never took place on a cpu. This is evident | |
2350 | * by the timestamp being before the start of the buffer. | |
2351 | */ | |
2352 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 2353 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
2354 | break; |
2355 | entries++; | |
2356 | ring_buffer_read(buf_iter, NULL); | |
2357 | } | |
2358 | ||
12883efb | 2359 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2360 | } |
2361 | ||
d7350c3f | 2362 | /* |
d7350c3f FW |
2363 | * The current tracer is copied to avoid a global locking |
2364 | * all around. | |
2365 | */ | |
bc0c38d1 SR |
2366 | static void *s_start(struct seq_file *m, loff_t *pos) |
2367 | { | |
2368 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2369 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2370 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2371 | void *p = NULL; |
2372 | loff_t l = 0; | |
3928a8a2 | 2373 | int cpu; |
bc0c38d1 | 2374 | |
2fd196ec HT |
2375 | /* |
2376 | * copy the tracer to avoid using a global lock all around. | |
2377 | * iter->trace is a copy of current_trace, the pointer to the | |
2378 | * name may be used instead of a strcmp(), as iter->trace->name | |
2379 | * will point to the same string as current_trace->name. | |
2380 | */ | |
bc0c38d1 | 2381 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2382 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2383 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2384 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2385 | |
12883efb | 2386 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2387 | if (iter->snapshot && iter->trace->use_max_tr) |
2388 | return ERR_PTR(-EBUSY); | |
12883efb | 2389 | #endif |
debdd57f HT |
2390 | |
2391 | if (!iter->snapshot) | |
2392 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2393 | |
bc0c38d1 SR |
2394 | if (*pos != iter->pos) { |
2395 | iter->ent = NULL; | |
2396 | iter->cpu = 0; | |
2397 | iter->idx = -1; | |
2398 | ||
ae3b5093 | 2399 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2400 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2401 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2402 | } else |
2f26ebd5 | 2403 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2404 | |
ac91d854 | 2405 | iter->leftover = 0; |
bc0c38d1 SR |
2406 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2407 | ; | |
2408 | ||
2409 | } else { | |
a63ce5b3 SR |
2410 | /* |
2411 | * If we overflowed the seq_file before, then we want | |
2412 | * to just reuse the trace_seq buffer again. | |
2413 | */ | |
2414 | if (iter->leftover) | |
2415 | p = iter; | |
2416 | else { | |
2417 | l = *pos - 1; | |
2418 | p = s_next(m, p, &l); | |
2419 | } | |
bc0c38d1 SR |
2420 | } |
2421 | ||
4f535968 | 2422 | trace_event_read_lock(); |
7e53bd42 | 2423 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2424 | return p; |
2425 | } | |
2426 | ||
2427 | static void s_stop(struct seq_file *m, void *p) | |
2428 | { | |
7e53bd42 LJ |
2429 | struct trace_iterator *iter = m->private; |
2430 | ||
12883efb | 2431 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2432 | if (iter->snapshot && iter->trace->use_max_tr) |
2433 | return; | |
12883efb | 2434 | #endif |
debdd57f HT |
2435 | |
2436 | if (!iter->snapshot) | |
2437 | atomic_dec(&trace_record_cmdline_disabled); | |
12883efb | 2438 | |
7e53bd42 | 2439 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2440 | trace_event_read_unlock(); |
bc0c38d1 SR |
2441 | } |
2442 | ||
39eaf7ef | 2443 | static void |
12883efb SRRH |
2444 | get_total_entries(struct trace_buffer *buf, |
2445 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
2446 | { |
2447 | unsigned long count; | |
2448 | int cpu; | |
2449 | ||
2450 | *total = 0; | |
2451 | *entries = 0; | |
2452 | ||
2453 | for_each_tracing_cpu(cpu) { | |
12883efb | 2454 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2455 | /* |
2456 | * If this buffer has skipped entries, then we hold all | |
2457 | * entries for the trace and we need to ignore the | |
2458 | * ones before the time stamp. | |
2459 | */ | |
12883efb SRRH |
2460 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
2461 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2462 | /* total is the same as the entries */ |
2463 | *total += count; | |
2464 | } else | |
2465 | *total += count + | |
12883efb | 2466 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2467 | *entries += count; |
2468 | } | |
2469 | } | |
2470 | ||
e309b41d | 2471 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2472 | { |
a6168353 ME |
2473 | seq_puts(m, "# _------=> CPU# \n"); |
2474 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
2475 | seq_puts(m, "# | / _----=> need-resched \n"); | |
2476 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
2477 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
2478 | seq_puts(m, "# |||| / delay \n"); |
2479 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
2480 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2481 | } |
2482 | ||
12883efb | 2483 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 2484 | { |
39eaf7ef SR |
2485 | unsigned long total; |
2486 | unsigned long entries; | |
2487 | ||
12883efb | 2488 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
2489 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
2490 | entries, total, num_online_cpus()); | |
2491 | seq_puts(m, "#\n"); | |
2492 | } | |
2493 | ||
12883efb | 2494 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) |
39eaf7ef | 2495 | { |
12883efb | 2496 | print_event_info(buf, m); |
77271ce4 | 2497 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
a6168353 | 2498 | seq_puts(m, "# | | | | |\n"); |
bc0c38d1 SR |
2499 | } |
2500 | ||
12883efb | 2501 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) |
77271ce4 | 2502 | { |
12883efb | 2503 | print_event_info(buf, m); |
77271ce4 SR |
2504 | seq_puts(m, "# _-----=> irqs-off\n"); |
2505 | seq_puts(m, "# / _----=> need-resched\n"); | |
2506 | seq_puts(m, "# | / _---=> hardirq/softirq\n"); | |
2507 | seq_puts(m, "# || / _--=> preempt-depth\n"); | |
2508 | seq_puts(m, "# ||| / delay\n"); | |
2509 | seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); | |
2510 | seq_puts(m, "# | | | |||| | |\n"); | |
2511 | } | |
bc0c38d1 | 2512 | |
62b915f1 | 2513 | void |
bc0c38d1 SR |
2514 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2515 | { | |
2516 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
12883efb SRRH |
2517 | struct trace_buffer *buf = iter->trace_buffer; |
2518 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 2519 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2520 | unsigned long entries; |
2521 | unsigned long total; | |
bc0c38d1 SR |
2522 | const char *name = "preemption"; |
2523 | ||
d840f718 | 2524 | name = type->name; |
bc0c38d1 | 2525 | |
12883efb | 2526 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 2527 | |
888b55dc | 2528 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2529 | name, UTS_RELEASE); |
888b55dc | 2530 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2531 | "---------------------------------\n"); |
888b55dc | 2532 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2533 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2534 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2535 | entries, |
4c11d7ae | 2536 | total, |
12883efb | 2537 | buf->cpu, |
bc0c38d1 SR |
2538 | #if defined(CONFIG_PREEMPT_NONE) |
2539 | "server", | |
2540 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2541 | "desktop", | |
b5c21b45 | 2542 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2543 | "preempt", |
2544 | #else | |
2545 | "unknown", | |
2546 | #endif | |
2547 | /* These are reserved for later use */ | |
2548 | 0, 0, 0, 0); | |
2549 | #ifdef CONFIG_SMP | |
2550 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2551 | #else | |
2552 | seq_puts(m, ")\n"); | |
2553 | #endif | |
888b55dc KM |
2554 | seq_puts(m, "# -----------------\n"); |
2555 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2556 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2557 | data->comm, data->pid, |
2558 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2559 | data->policy, data->rt_priority); |
888b55dc | 2560 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2561 | |
2562 | if (data->critical_start) { | |
888b55dc | 2563 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2564 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2565 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2566 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2567 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2568 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2569 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2570 | } |
2571 | ||
888b55dc | 2572 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2573 | } |
2574 | ||
a309720c SR |
2575 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2576 | { | |
2577 | struct trace_seq *s = &iter->seq; | |
2578 | ||
12ef7d44 SR |
2579 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2580 | return; | |
2581 | ||
2582 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2583 | return; | |
2584 | ||
4462344e | 2585 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2586 | return; |
2587 | ||
12883efb | 2588 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
2589 | return; |
2590 | ||
4462344e | 2591 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2592 | |
2593 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2594 | if (iter->idx > 1) | |
2595 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2596 | iter->cpu); | |
a309720c SR |
2597 | } |
2598 | ||
2c4f035f | 2599 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2600 | { |
214023c3 | 2601 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2602 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2603 | struct trace_entry *entry; |
f633cef0 | 2604 | struct trace_event *event; |
bc0c38d1 | 2605 | |
4e3c3333 | 2606 | entry = iter->ent; |
dd0e545f | 2607 | |
a309720c SR |
2608 | test_cpu_buff_start(iter); |
2609 | ||
c4a8e8be | 2610 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2611 | |
c4a8e8be | 2612 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
2613 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2614 | if (!trace_print_lat_context(iter)) | |
2615 | goto partial; | |
2616 | } else { | |
2617 | if (!trace_print_context(iter)) | |
2618 | goto partial; | |
2619 | } | |
c4a8e8be | 2620 | } |
bc0c38d1 | 2621 | |
268ccda0 | 2622 | if (event) |
a9a57763 | 2623 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
2624 | |
2625 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
2626 | goto partial; | |
02b67518 | 2627 | |
2c4f035f | 2628 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2629 | partial: |
2630 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
2631 | } |
2632 | ||
2c4f035f | 2633 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2634 | { |
2635 | struct trace_seq *s = &iter->seq; | |
2636 | struct trace_entry *entry; | |
f633cef0 | 2637 | struct trace_event *event; |
f9896bf3 IM |
2638 | |
2639 | entry = iter->ent; | |
dd0e545f | 2640 | |
c4a8e8be | 2641 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
2642 | if (!trace_seq_printf(s, "%d %d %llu ", |
2643 | entry->pid, iter->cpu, iter->ts)) | |
2644 | goto partial; | |
c4a8e8be | 2645 | } |
f9896bf3 | 2646 | |
f633cef0 | 2647 | event = ftrace_find_event(entry->type); |
268ccda0 | 2648 | if (event) |
a9a57763 | 2649 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
2650 | |
2651 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
2652 | goto partial; | |
777e208d | 2653 | |
2c4f035f | 2654 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2655 | partial: |
2656 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
2657 | } |
2658 | ||
2c4f035f | 2659 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2660 | { |
2661 | struct trace_seq *s = &iter->seq; | |
2662 | unsigned char newline = '\n'; | |
2663 | struct trace_entry *entry; | |
f633cef0 | 2664 | struct trace_event *event; |
5e3ca0ec IM |
2665 | |
2666 | entry = iter->ent; | |
dd0e545f | 2667 | |
c4a8e8be FW |
2668 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2669 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
2670 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
2671 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
2672 | } | |
5e3ca0ec | 2673 | |
f633cef0 | 2674 | event = ftrace_find_event(entry->type); |
268ccda0 | 2675 | if (event) { |
a9a57763 | 2676 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2677 | if (ret != TRACE_TYPE_HANDLED) |
2678 | return ret; | |
2679 | } | |
7104f300 | 2680 | |
5e3ca0ec IM |
2681 | SEQ_PUT_FIELD_RET(s, newline); |
2682 | ||
2c4f035f | 2683 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
2684 | } |
2685 | ||
2c4f035f | 2686 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2687 | { |
2688 | struct trace_seq *s = &iter->seq; | |
2689 | struct trace_entry *entry; | |
f633cef0 | 2690 | struct trace_event *event; |
cb0f12aa IM |
2691 | |
2692 | entry = iter->ent; | |
dd0e545f | 2693 | |
c4a8e8be FW |
2694 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2695 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 2696 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2697 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2698 | } | |
cb0f12aa | 2699 | |
f633cef0 | 2700 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2701 | return event ? event->funcs->binary(iter, 0, event) : |
2702 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2703 | } |
2704 | ||
62b915f1 | 2705 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2706 | { |
6d158a81 | 2707 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2708 | int cpu; |
2709 | ||
9aba60fe | 2710 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 2711 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 2712 | cpu = iter->cpu_file; |
6d158a81 SR |
2713 | buf_iter = trace_buffer_iter(iter, cpu); |
2714 | if (buf_iter) { | |
2715 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2716 | return 0; |
2717 | } else { | |
12883efb | 2718 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
2719 | return 0; |
2720 | } | |
2721 | return 1; | |
2722 | } | |
2723 | ||
ab46428c | 2724 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2725 | buf_iter = trace_buffer_iter(iter, cpu); |
2726 | if (buf_iter) { | |
2727 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2728 | return 0; |
2729 | } else { | |
12883efb | 2730 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
2731 | return 0; |
2732 | } | |
bc0c38d1 | 2733 | } |
d769041f | 2734 | |
797d3712 | 2735 | return 1; |
bc0c38d1 SR |
2736 | } |
2737 | ||
4f535968 | 2738 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2739 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2740 | { |
2c4f035f FW |
2741 | enum print_line_t ret; |
2742 | ||
ee5e51f5 JO |
2743 | if (iter->lost_events && |
2744 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2745 | iter->cpu, iter->lost_events)) | |
2746 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2747 | |
2c4f035f FW |
2748 | if (iter->trace && iter->trace->print_line) { |
2749 | ret = iter->trace->print_line(iter); | |
2750 | if (ret != TRACE_TYPE_UNHANDLED) | |
2751 | return ret; | |
2752 | } | |
72829bc3 | 2753 | |
09ae7234 SRRH |
2754 | if (iter->ent->type == TRACE_BPUTS && |
2755 | trace_flags & TRACE_ITER_PRINTK && | |
2756 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
2757 | return trace_print_bputs_msg_only(iter); | |
2758 | ||
48ead020 FW |
2759 | if (iter->ent->type == TRACE_BPRINT && |
2760 | trace_flags & TRACE_ITER_PRINTK && | |
2761 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2762 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2763 | |
66896a85 FW |
2764 | if (iter->ent->type == TRACE_PRINT && |
2765 | trace_flags & TRACE_ITER_PRINTK && | |
2766 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2767 | return trace_print_printk_msg_only(iter); |
66896a85 | 2768 | |
cb0f12aa IM |
2769 | if (trace_flags & TRACE_ITER_BIN) |
2770 | return print_bin_fmt(iter); | |
2771 | ||
5e3ca0ec IM |
2772 | if (trace_flags & TRACE_ITER_HEX) |
2773 | return print_hex_fmt(iter); | |
2774 | ||
f9896bf3 IM |
2775 | if (trace_flags & TRACE_ITER_RAW) |
2776 | return print_raw_fmt(iter); | |
2777 | ||
f9896bf3 IM |
2778 | return print_trace_fmt(iter); |
2779 | } | |
2780 | ||
7e9a49ef JO |
2781 | void trace_latency_header(struct seq_file *m) |
2782 | { | |
2783 | struct trace_iterator *iter = m->private; | |
2784 | ||
2785 | /* print nothing if the buffers are empty */ | |
2786 | if (trace_empty(iter)) | |
2787 | return; | |
2788 | ||
2789 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2790 | print_trace_header(m, iter); | |
2791 | ||
2792 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2793 | print_lat_help_header(m); | |
2794 | } | |
2795 | ||
62b915f1 JO |
2796 | void trace_default_header(struct seq_file *m) |
2797 | { | |
2798 | struct trace_iterator *iter = m->private; | |
2799 | ||
f56e7f8e JO |
2800 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2801 | return; | |
2802 | ||
62b915f1 JO |
2803 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2804 | /* print nothing if the buffers are empty */ | |
2805 | if (trace_empty(iter)) | |
2806 | return; | |
2807 | print_trace_header(m, iter); | |
2808 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2809 | print_lat_help_header(m); | |
2810 | } else { | |
77271ce4 SR |
2811 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2812 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
12883efb | 2813 | print_func_help_header_irq(iter->trace_buffer, m); |
77271ce4 | 2814 | else |
12883efb | 2815 | print_func_help_header(iter->trace_buffer, m); |
77271ce4 | 2816 | } |
62b915f1 JO |
2817 | } |
2818 | } | |
2819 | ||
e0a413f6 SR |
2820 | static void test_ftrace_alive(struct seq_file *m) |
2821 | { | |
2822 | if (!ftrace_is_dead()) | |
2823 | return; | |
2824 | seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
2825 | seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n"); | |
2826 | } | |
2827 | ||
d8741e2e | 2828 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 2829 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 2830 | { |
d8741e2e SRRH |
2831 | seq_printf(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n"); |
2832 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2833 | seq_printf(m, "# Takes a snapshot of the main buffer.\n"); | |
b9be6d02 | 2834 | seq_printf(m, "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n"); |
d8741e2e SRRH |
2835 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); |
2836 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2837 | } | |
f1affcaa SRRH |
2838 | |
2839 | static void show_snapshot_percpu_help(struct seq_file *m) | |
2840 | { | |
2841 | seq_printf(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); | |
2842 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP | |
2843 | seq_printf(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n"); | |
2844 | seq_printf(m, "# Takes a snapshot of the main buffer for this cpu.\n"); | |
2845 | #else | |
2846 | seq_printf(m, "# echo 1 > snapshot : Not supported with this kernel.\n"); | |
2847 | seq_printf(m, "# Must use main snapshot file to allocate.\n"); | |
2848 | #endif | |
2849 | seq_printf(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n"); | |
2850 | seq_printf(m, "# (Doesn't have to be '2' works with any number that\n"); | |
2851 | seq_printf(m, "# is not a '0' or '1')\n"); | |
2852 | } | |
2853 | ||
d8741e2e SRRH |
2854 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
2855 | { | |
45ad21ca | 2856 | if (iter->tr->allocated_snapshot) |
d8741e2e SRRH |
2857 | seq_printf(m, "#\n# * Snapshot is allocated *\n#\n"); |
2858 | else | |
2859 | seq_printf(m, "#\n# * Snapshot is freed *\n#\n"); | |
2860 | ||
2861 | seq_printf(m, "# Snapshot commands:\n"); | |
f1affcaa SRRH |
2862 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
2863 | show_snapshot_main_help(m); | |
2864 | else | |
2865 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
2866 | } |
2867 | #else | |
2868 | /* Should never be called */ | |
2869 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
2870 | #endif | |
2871 | ||
bc0c38d1 SR |
2872 | static int s_show(struct seq_file *m, void *v) |
2873 | { | |
2874 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2875 | int ret; |
bc0c38d1 SR |
2876 | |
2877 | if (iter->ent == NULL) { | |
2878 | if (iter->tr) { | |
2879 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2880 | seq_puts(m, "#\n"); | |
e0a413f6 | 2881 | test_ftrace_alive(m); |
bc0c38d1 | 2882 | } |
d8741e2e SRRH |
2883 | if (iter->snapshot && trace_empty(iter)) |
2884 | print_snapshot_help(m, iter); | |
2885 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 2886 | iter->trace->print_header(m); |
62b915f1 JO |
2887 | else |
2888 | trace_default_header(m); | |
2889 | ||
a63ce5b3 SR |
2890 | } else if (iter->leftover) { |
2891 | /* | |
2892 | * If we filled the seq_file buffer earlier, we | |
2893 | * want to just show it now. | |
2894 | */ | |
2895 | ret = trace_print_seq(m, &iter->seq); | |
2896 | ||
2897 | /* ret should this time be zero, but you never know */ | |
2898 | iter->leftover = ret; | |
2899 | ||
bc0c38d1 | 2900 | } else { |
f9896bf3 | 2901 | print_trace_line(iter); |
a63ce5b3 SR |
2902 | ret = trace_print_seq(m, &iter->seq); |
2903 | /* | |
2904 | * If we overflow the seq_file buffer, then it will | |
2905 | * ask us for this data again at start up. | |
2906 | * Use that instead. | |
2907 | * ret is 0 if seq_file write succeeded. | |
2908 | * -1 otherwise. | |
2909 | */ | |
2910 | iter->leftover = ret; | |
bc0c38d1 SR |
2911 | } |
2912 | ||
2913 | return 0; | |
2914 | } | |
2915 | ||
649e9c70 ON |
2916 | /* |
2917 | * Should be used after trace_array_get(), trace_types_lock | |
2918 | * ensures that i_cdev was already initialized. | |
2919 | */ | |
2920 | static inline int tracing_get_cpu(struct inode *inode) | |
2921 | { | |
2922 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
2923 | return (long)inode->i_cdev - 1; | |
2924 | return RING_BUFFER_ALL_CPUS; | |
2925 | } | |
2926 | ||
88e9d34c | 2927 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2928 | .start = s_start, |
2929 | .next = s_next, | |
2930 | .stop = s_stop, | |
2931 | .show = s_show, | |
bc0c38d1 SR |
2932 | }; |
2933 | ||
e309b41d | 2934 | static struct trace_iterator * |
6484c71c | 2935 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 2936 | { |
6484c71c | 2937 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 2938 | struct trace_iterator *iter; |
50e18b94 | 2939 | int cpu; |
bc0c38d1 | 2940 | |
85a2f9b4 SR |
2941 | if (tracing_disabled) |
2942 | return ERR_PTR(-ENODEV); | |
60a11774 | 2943 | |
50e18b94 | 2944 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2945 | if (!iter) |
2946 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2947 | |
6d158a81 SR |
2948 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
2949 | GFP_KERNEL); | |
93574fcc DC |
2950 | if (!iter->buffer_iter) |
2951 | goto release; | |
2952 | ||
d7350c3f FW |
2953 | /* |
2954 | * We make a copy of the current tracer to avoid concurrent | |
2955 | * changes on it while we are reading. | |
2956 | */ | |
bc0c38d1 | 2957 | mutex_lock(&trace_types_lock); |
d7350c3f | 2958 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2959 | if (!iter->trace) |
d7350c3f | 2960 | goto fail; |
85a2f9b4 | 2961 | |
2b6080f2 | 2962 | *iter->trace = *tr->current_trace; |
d7350c3f | 2963 | |
79f55997 | 2964 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2965 | goto fail; |
2966 | ||
12883efb SRRH |
2967 | iter->tr = tr; |
2968 | ||
2969 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
2970 | /* Currently only the top directory has a snapshot */ |
2971 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 2972 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 2973 | else |
12883efb SRRH |
2974 | #endif |
2975 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 2976 | iter->snapshot = snapshot; |
bc0c38d1 | 2977 | iter->pos = -1; |
6484c71c | 2978 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 2979 | mutex_init(&iter->mutex); |
bc0c38d1 | 2980 | |
8bba1bf5 MM |
2981 | /* Notify the tracer early; before we stop tracing. */ |
2982 | if (iter->trace && iter->trace->open) | |
a93751ca | 2983 | iter->trace->open(iter); |
8bba1bf5 | 2984 | |
12ef7d44 | 2985 | /* Annotate start of buffers if we had overruns */ |
12883efb | 2986 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
2987 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
2988 | ||
8be0709f | 2989 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 2990 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
2991 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
2992 | ||
debdd57f HT |
2993 | /* stop the trace while dumping if we are not opening "snapshot" */ |
2994 | if (!iter->snapshot) | |
2b6080f2 | 2995 | tracing_stop_tr(tr); |
2f26ebd5 | 2996 | |
ae3b5093 | 2997 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2998 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 2999 | iter->buffer_iter[cpu] = |
12883efb | 3000 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3001 | } |
3002 | ring_buffer_read_prepare_sync(); | |
3003 | for_each_tracing_cpu(cpu) { | |
3004 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3005 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
3006 | } |
3007 | } else { | |
3008 | cpu = iter->cpu_file; | |
3928a8a2 | 3009 | iter->buffer_iter[cpu] = |
12883efb | 3010 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3011 | ring_buffer_read_prepare_sync(); |
3012 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3013 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
3014 | } |
3015 | ||
bc0c38d1 SR |
3016 | mutex_unlock(&trace_types_lock); |
3017 | ||
bc0c38d1 | 3018 | return iter; |
3928a8a2 | 3019 | |
d7350c3f | 3020 | fail: |
3928a8a2 | 3021 | mutex_unlock(&trace_types_lock); |
d7350c3f | 3022 | kfree(iter->trace); |
6d158a81 | 3023 | kfree(iter->buffer_iter); |
93574fcc | 3024 | release: |
50e18b94 JO |
3025 | seq_release_private(inode, file); |
3026 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
3027 | } |
3028 | ||
3029 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
3030 | { | |
60a11774 SR |
3031 | if (tracing_disabled) |
3032 | return -ENODEV; | |
3033 | ||
bc0c38d1 SR |
3034 | filp->private_data = inode->i_private; |
3035 | return 0; | |
3036 | } | |
3037 | ||
2e86421d GB |
3038 | bool tracing_is_disabled(void) |
3039 | { | |
3040 | return (tracing_disabled) ? true: false; | |
3041 | } | |
3042 | ||
7b85af63 SRRH |
3043 | /* |
3044 | * Open and update trace_array ref count. | |
3045 | * Must have the current trace_array passed to it. | |
3046 | */ | |
dcc30223 | 3047 | static int tracing_open_generic_tr(struct inode *inode, struct file *filp) |
7b85af63 SRRH |
3048 | { |
3049 | struct trace_array *tr = inode->i_private; | |
3050 | ||
3051 | if (tracing_disabled) | |
3052 | return -ENODEV; | |
3053 | ||
3054 | if (trace_array_get(tr) < 0) | |
3055 | return -ENODEV; | |
3056 | ||
3057 | filp->private_data = inode->i_private; | |
3058 | ||
3059 | return 0; | |
7b85af63 SRRH |
3060 | } |
3061 | ||
4fd27358 | 3062 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 3063 | { |
6484c71c | 3064 | struct trace_array *tr = inode->i_private; |
907f2784 | 3065 | struct seq_file *m = file->private_data; |
4acd4d00 | 3066 | struct trace_iterator *iter; |
3928a8a2 | 3067 | int cpu; |
bc0c38d1 | 3068 | |
ff451961 | 3069 | if (!(file->f_mode & FMODE_READ)) { |
6484c71c | 3070 | trace_array_put(tr); |
4acd4d00 | 3071 | return 0; |
ff451961 | 3072 | } |
4acd4d00 | 3073 | |
6484c71c | 3074 | /* Writes do not use seq_file */ |
4acd4d00 | 3075 | iter = m->private; |
bc0c38d1 | 3076 | mutex_lock(&trace_types_lock); |
a695cb58 | 3077 | |
3928a8a2 SR |
3078 | for_each_tracing_cpu(cpu) { |
3079 | if (iter->buffer_iter[cpu]) | |
3080 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
3081 | } | |
3082 | ||
bc0c38d1 SR |
3083 | if (iter->trace && iter->trace->close) |
3084 | iter->trace->close(iter); | |
3085 | ||
debdd57f HT |
3086 | if (!iter->snapshot) |
3087 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 3088 | tracing_start_tr(tr); |
f77d09a3 AL |
3089 | |
3090 | __trace_array_put(tr); | |
3091 | ||
bc0c38d1 SR |
3092 | mutex_unlock(&trace_types_lock); |
3093 | ||
d7350c3f | 3094 | mutex_destroy(&iter->mutex); |
b0dfa978 | 3095 | free_cpumask_var(iter->started); |
d7350c3f | 3096 | kfree(iter->trace); |
6d158a81 | 3097 | kfree(iter->buffer_iter); |
50e18b94 | 3098 | seq_release_private(inode, file); |
ff451961 | 3099 | |
bc0c38d1 SR |
3100 | return 0; |
3101 | } | |
3102 | ||
7b85af63 SRRH |
3103 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
3104 | { | |
3105 | struct trace_array *tr = inode->i_private; | |
3106 | ||
3107 | trace_array_put(tr); | |
bc0c38d1 SR |
3108 | return 0; |
3109 | } | |
3110 | ||
7b85af63 SRRH |
3111 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
3112 | { | |
3113 | struct trace_array *tr = inode->i_private; | |
3114 | ||
3115 | trace_array_put(tr); | |
3116 | ||
3117 | return single_release(inode, file); | |
3118 | } | |
3119 | ||
bc0c38d1 SR |
3120 | static int tracing_open(struct inode *inode, struct file *file) |
3121 | { | |
6484c71c | 3122 | struct trace_array *tr = inode->i_private; |
85a2f9b4 SR |
3123 | struct trace_iterator *iter; |
3124 | int ret = 0; | |
bc0c38d1 | 3125 | |
ff451961 SRRH |
3126 | if (trace_array_get(tr) < 0) |
3127 | return -ENODEV; | |
3128 | ||
4acd4d00 | 3129 | /* If this file was open for write, then erase contents */ |
6484c71c ON |
3130 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
3131 | int cpu = tracing_get_cpu(inode); | |
3132 | ||
3133 | if (cpu == RING_BUFFER_ALL_CPUS) | |
12883efb | 3134 | tracing_reset_online_cpus(&tr->trace_buffer); |
4acd4d00 | 3135 | else |
6484c71c | 3136 | tracing_reset(&tr->trace_buffer, cpu); |
4acd4d00 | 3137 | } |
bc0c38d1 | 3138 | |
4acd4d00 | 3139 | if (file->f_mode & FMODE_READ) { |
6484c71c | 3140 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
3141 | if (IS_ERR(iter)) |
3142 | ret = PTR_ERR(iter); | |
3143 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
3144 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3145 | } | |
ff451961 SRRH |
3146 | |
3147 | if (ret < 0) | |
3148 | trace_array_put(tr); | |
3149 | ||
bc0c38d1 SR |
3150 | return ret; |
3151 | } | |
3152 | ||
607e2ea1 SRRH |
3153 | /* |
3154 | * Some tracers are not suitable for instance buffers. | |
3155 | * A tracer is always available for the global array (toplevel) | |
3156 | * or if it explicitly states that it is. | |
3157 | */ | |
3158 | static bool | |
3159 | trace_ok_for_array(struct tracer *t, struct trace_array *tr) | |
3160 | { | |
3161 | return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; | |
3162 | } | |
3163 | ||
3164 | /* Find the next tracer that this trace array may use */ | |
3165 | static struct tracer * | |
3166 | get_tracer_for_array(struct trace_array *tr, struct tracer *t) | |
3167 | { | |
3168 | while (t && !trace_ok_for_array(t, tr)) | |
3169 | t = t->next; | |
3170 | ||
3171 | return t; | |
3172 | } | |
3173 | ||
e309b41d | 3174 | static void * |
bc0c38d1 SR |
3175 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3176 | { | |
607e2ea1 | 3177 | struct trace_array *tr = m->private; |
f129e965 | 3178 | struct tracer *t = v; |
bc0c38d1 SR |
3179 | |
3180 | (*pos)++; | |
3181 | ||
3182 | if (t) | |
607e2ea1 | 3183 | t = get_tracer_for_array(tr, t->next); |
bc0c38d1 | 3184 | |
bc0c38d1 SR |
3185 | return t; |
3186 | } | |
3187 | ||
3188 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3189 | { | |
607e2ea1 | 3190 | struct trace_array *tr = m->private; |
f129e965 | 3191 | struct tracer *t; |
bc0c38d1 SR |
3192 | loff_t l = 0; |
3193 | ||
3194 | mutex_lock(&trace_types_lock); | |
607e2ea1 SRRH |
3195 | |
3196 | t = get_tracer_for_array(tr, trace_types); | |
3197 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
3198 | ; | |
bc0c38d1 SR |
3199 | |
3200 | return t; | |
3201 | } | |
3202 | ||
3203 | static void t_stop(struct seq_file *m, void *p) | |
3204 | { | |
3205 | mutex_unlock(&trace_types_lock); | |
3206 | } | |
3207 | ||
3208 | static int t_show(struct seq_file *m, void *v) | |
3209 | { | |
3210 | struct tracer *t = v; | |
3211 | ||
3212 | if (!t) | |
3213 | return 0; | |
3214 | ||
3215 | seq_printf(m, "%s", t->name); | |
3216 | if (t->next) | |
3217 | seq_putc(m, ' '); | |
3218 | else | |
3219 | seq_putc(m, '\n'); | |
3220 | ||
3221 | return 0; | |
3222 | } | |
3223 | ||
88e9d34c | 3224 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
3225 | .start = t_start, |
3226 | .next = t_next, | |
3227 | .stop = t_stop, | |
3228 | .show = t_show, | |
bc0c38d1 SR |
3229 | }; |
3230 | ||
3231 | static int show_traces_open(struct inode *inode, struct file *file) | |
3232 | { | |
607e2ea1 SRRH |
3233 | struct trace_array *tr = inode->i_private; |
3234 | struct seq_file *m; | |
3235 | int ret; | |
3236 | ||
60a11774 SR |
3237 | if (tracing_disabled) |
3238 | return -ENODEV; | |
3239 | ||
607e2ea1 SRRH |
3240 | ret = seq_open(file, &show_traces_seq_ops); |
3241 | if (ret) | |
3242 | return ret; | |
3243 | ||
3244 | m = file->private_data; | |
3245 | m->private = tr; | |
3246 | ||
3247 | return 0; | |
bc0c38d1 SR |
3248 | } |
3249 | ||
4acd4d00 SR |
3250 | static ssize_t |
3251 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
3252 | size_t count, loff_t *ppos) | |
3253 | { | |
3254 | return count; | |
3255 | } | |
3256 | ||
098c879e | 3257 | loff_t tracing_lseek(struct file *file, loff_t offset, int whence) |
364829b1 | 3258 | { |
098c879e SRRH |
3259 | int ret; |
3260 | ||
364829b1 | 3261 | if (file->f_mode & FMODE_READ) |
098c879e | 3262 | ret = seq_lseek(file, offset, whence); |
364829b1 | 3263 | else |
098c879e SRRH |
3264 | file->f_pos = ret = 0; |
3265 | ||
3266 | return ret; | |
364829b1 SP |
3267 | } |
3268 | ||
5e2336a0 | 3269 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
3270 | .open = tracing_open, |
3271 | .read = seq_read, | |
4acd4d00 | 3272 | .write = tracing_write_stub, |
098c879e | 3273 | .llseek = tracing_lseek, |
4bf39a94 | 3274 | .release = tracing_release, |
bc0c38d1 SR |
3275 | }; |
3276 | ||
5e2336a0 | 3277 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
3278 | .open = show_traces_open, |
3279 | .read = seq_read, | |
3280 | .release = seq_release, | |
b444786f | 3281 | .llseek = seq_lseek, |
c7078de1 IM |
3282 | }; |
3283 | ||
36dfe925 IM |
3284 | /* |
3285 | * The tracer itself will not take this lock, but still we want | |
3286 | * to provide a consistent cpumask to user-space: | |
3287 | */ | |
3288 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
3289 | ||
3290 | /* | |
3291 | * Temporary storage for the character representation of the | |
3292 | * CPU bitmask (and one more byte for the newline): | |
3293 | */ | |
3294 | static char mask_str[NR_CPUS + 1]; | |
3295 | ||
c7078de1 IM |
3296 | static ssize_t |
3297 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
3298 | size_t count, loff_t *ppos) | |
3299 | { | |
ccfe9e42 | 3300 | struct trace_array *tr = file_inode(filp)->i_private; |
36dfe925 | 3301 | int len; |
c7078de1 IM |
3302 | |
3303 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 3304 | |
ccfe9e42 | 3305 | len = cpumask_scnprintf(mask_str, count, tr->tracing_cpumask); |
36dfe925 IM |
3306 | if (count - len < 2) { |
3307 | count = -EINVAL; | |
3308 | goto out_err; | |
3309 | } | |
3310 | len += sprintf(mask_str + len, "\n"); | |
3311 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
3312 | ||
3313 | out_err: | |
c7078de1 IM |
3314 | mutex_unlock(&tracing_cpumask_update_lock); |
3315 | ||
3316 | return count; | |
3317 | } | |
3318 | ||
3319 | static ssize_t | |
3320 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
3321 | size_t count, loff_t *ppos) | |
3322 | { | |
ccfe9e42 | 3323 | struct trace_array *tr = file_inode(filp)->i_private; |
9e01c1b7 | 3324 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 3325 | int err, cpu; |
9e01c1b7 RR |
3326 | |
3327 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
3328 | return -ENOMEM; | |
c7078de1 | 3329 | |
9e01c1b7 | 3330 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 3331 | if (err) |
36dfe925 IM |
3332 | goto err_unlock; |
3333 | ||
215368e8 LZ |
3334 | mutex_lock(&tracing_cpumask_update_lock); |
3335 | ||
a5e25883 | 3336 | local_irq_disable(); |
0b9b12c1 | 3337 | arch_spin_lock(&tr->max_lock); |
ab46428c | 3338 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
3339 | /* |
3340 | * Increase/decrease the disabled counter if we are | |
3341 | * about to flip a bit in the cpumask: | |
3342 | */ | |
ccfe9e42 | 3343 | if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3344 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3345 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3346 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 3347 | } |
ccfe9e42 | 3348 | if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3349 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3350 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3351 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
3352 | } |
3353 | } | |
0b9b12c1 | 3354 | arch_spin_unlock(&tr->max_lock); |
a5e25883 | 3355 | local_irq_enable(); |
36dfe925 | 3356 | |
ccfe9e42 | 3357 | cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
3358 | |
3359 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 3360 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
3361 | |
3362 | return count; | |
36dfe925 IM |
3363 | |
3364 | err_unlock: | |
215368e8 | 3365 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
3366 | |
3367 | return err; | |
c7078de1 IM |
3368 | } |
3369 | ||
5e2336a0 | 3370 | static const struct file_operations tracing_cpumask_fops = { |
ccfe9e42 | 3371 | .open = tracing_open_generic_tr, |
c7078de1 IM |
3372 | .read = tracing_cpumask_read, |
3373 | .write = tracing_cpumask_write, | |
ccfe9e42 | 3374 | .release = tracing_release_generic_tr, |
b444786f | 3375 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3376 | }; |
3377 | ||
fdb372ed | 3378 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 3379 | { |
d8e83d26 | 3380 | struct tracer_opt *trace_opts; |
2b6080f2 | 3381 | struct trace_array *tr = m->private; |
d8e83d26 | 3382 | u32 tracer_flags; |
d8e83d26 | 3383 | int i; |
adf9f195 | 3384 | |
d8e83d26 | 3385 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3386 | tracer_flags = tr->current_trace->flags->val; |
3387 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 3388 | |
bc0c38d1 SR |
3389 | for (i = 0; trace_options[i]; i++) { |
3390 | if (trace_flags & (1 << i)) | |
fdb372ed | 3391 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 3392 | else |
fdb372ed | 3393 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
3394 | } |
3395 | ||
adf9f195 FW |
3396 | for (i = 0; trace_opts[i].name; i++) { |
3397 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 3398 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 3399 | else |
fdb372ed | 3400 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 3401 | } |
d8e83d26 | 3402 | mutex_unlock(&trace_types_lock); |
adf9f195 | 3403 | |
fdb372ed | 3404 | return 0; |
bc0c38d1 | 3405 | } |
bc0c38d1 | 3406 | |
8c1a49ae | 3407 | static int __set_tracer_option(struct trace_array *tr, |
8d18eaaf LZ |
3408 | struct tracer_flags *tracer_flags, |
3409 | struct tracer_opt *opts, int neg) | |
3410 | { | |
8c1a49ae | 3411 | struct tracer *trace = tr->current_trace; |
8d18eaaf | 3412 | int ret; |
bc0c38d1 | 3413 | |
8c1a49ae | 3414 | ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); |
8d18eaaf LZ |
3415 | if (ret) |
3416 | return ret; | |
3417 | ||
3418 | if (neg) | |
3419 | tracer_flags->val &= ~opts->bit; | |
3420 | else | |
3421 | tracer_flags->val |= opts->bit; | |
3422 | return 0; | |
bc0c38d1 SR |
3423 | } |
3424 | ||
adf9f195 | 3425 | /* Try to assign a tracer specific option */ |
8c1a49ae | 3426 | static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) |
adf9f195 | 3427 | { |
8c1a49ae | 3428 | struct tracer *trace = tr->current_trace; |
7770841e | 3429 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 3430 | struct tracer_opt *opts = NULL; |
8d18eaaf | 3431 | int i; |
adf9f195 | 3432 | |
7770841e Z |
3433 | for (i = 0; tracer_flags->opts[i].name; i++) { |
3434 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 3435 | |
8d18eaaf | 3436 | if (strcmp(cmp, opts->name) == 0) |
8c1a49ae | 3437 | return __set_tracer_option(tr, trace->flags, opts, neg); |
adf9f195 | 3438 | } |
adf9f195 | 3439 | |
8d18eaaf | 3440 | return -EINVAL; |
adf9f195 FW |
3441 | } |
3442 | ||
613f04a0 SRRH |
3443 | /* Some tracers require overwrite to stay enabled */ |
3444 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
3445 | { | |
3446 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
3447 | return -1; | |
3448 | ||
3449 | return 0; | |
3450 | } | |
3451 | ||
2b6080f2 | 3452 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
3453 | { |
3454 | /* do nothing if flag is already set */ | |
3455 | if (!!(trace_flags & mask) == !!enabled) | |
613f04a0 SRRH |
3456 | return 0; |
3457 | ||
3458 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 | 3459 | if (tr->current_trace->flag_changed) |
bf6065b5 | 3460 | if (tr->current_trace->flag_changed(tr, mask, !!enabled)) |
613f04a0 | 3461 | return -EINVAL; |
af4617bd SR |
3462 | |
3463 | if (enabled) | |
3464 | trace_flags |= mask; | |
3465 | else | |
3466 | trace_flags &= ~mask; | |
e870e9a1 LZ |
3467 | |
3468 | if (mask == TRACE_ITER_RECORD_CMD) | |
3469 | trace_event_enable_cmd_record(enabled); | |
750912fa | 3470 | |
80902822 | 3471 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 3472 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 3473 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 3474 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
3475 | #endif |
3476 | } | |
81698831 SR |
3477 | |
3478 | if (mask == TRACE_ITER_PRINTK) | |
3479 | trace_printk_start_stop_comm(enabled); | |
613f04a0 SRRH |
3480 | |
3481 | return 0; | |
af4617bd SR |
3482 | } |
3483 | ||
2b6080f2 | 3484 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 3485 | { |
8d18eaaf | 3486 | char *cmp; |
bc0c38d1 | 3487 | int neg = 0; |
613f04a0 | 3488 | int ret = -ENODEV; |
bc0c38d1 SR |
3489 | int i; |
3490 | ||
7bcfaf54 | 3491 | cmp = strstrip(option); |
bc0c38d1 | 3492 | |
8d18eaaf | 3493 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3494 | neg = 1; |
3495 | cmp += 2; | |
3496 | } | |
3497 | ||
69d34da2 SRRH |
3498 | mutex_lock(&trace_types_lock); |
3499 | ||
bc0c38d1 | 3500 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3501 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3502 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3503 | break; |
3504 | } | |
3505 | } | |
adf9f195 FW |
3506 | |
3507 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3508 | if (!trace_options[i]) |
8c1a49ae | 3509 | ret = set_tracer_option(tr, cmp, neg); |
69d34da2 SRRH |
3510 | |
3511 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3512 | |
7bcfaf54 SR |
3513 | return ret; |
3514 | } | |
3515 | ||
3516 | static ssize_t | |
3517 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3518 | size_t cnt, loff_t *ppos) | |
3519 | { | |
2b6080f2 SR |
3520 | struct seq_file *m = filp->private_data; |
3521 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3522 | char buf[64]; |
613f04a0 | 3523 | int ret; |
7bcfaf54 SR |
3524 | |
3525 | if (cnt >= sizeof(buf)) | |
3526 | return -EINVAL; | |
3527 | ||
3528 | if (copy_from_user(&buf, ubuf, cnt)) | |
3529 | return -EFAULT; | |
3530 | ||
a8dd2176 SR |
3531 | buf[cnt] = 0; |
3532 | ||
2b6080f2 | 3533 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
3534 | if (ret < 0) |
3535 | return ret; | |
7bcfaf54 | 3536 | |
cf8517cf | 3537 | *ppos += cnt; |
bc0c38d1 SR |
3538 | |
3539 | return cnt; | |
3540 | } | |
3541 | ||
fdb372ed LZ |
3542 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
3543 | { | |
7b85af63 | 3544 | struct trace_array *tr = inode->i_private; |
f77d09a3 | 3545 | int ret; |
7b85af63 | 3546 | |
fdb372ed LZ |
3547 | if (tracing_disabled) |
3548 | return -ENODEV; | |
2b6080f2 | 3549 | |
7b85af63 SRRH |
3550 | if (trace_array_get(tr) < 0) |
3551 | return -ENODEV; | |
3552 | ||
f77d09a3 AL |
3553 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
3554 | if (ret < 0) | |
3555 | trace_array_put(tr); | |
3556 | ||
3557 | return ret; | |
fdb372ed LZ |
3558 | } |
3559 | ||
5e2336a0 | 3560 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
3561 | .open = tracing_trace_options_open, |
3562 | .read = seq_read, | |
3563 | .llseek = seq_lseek, | |
7b85af63 | 3564 | .release = tracing_single_release_tr, |
ee6bce52 | 3565 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
3566 | }; |
3567 | ||
7bd2f24c IM |
3568 | static const char readme_msg[] = |
3569 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
3570 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
3571 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
3572 | " Important files:\n" | |
3573 | " trace\t\t\t- The static contents of the buffer\n" | |
3574 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
3575 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
3576 | " current_tracer\t- function and latency tracers\n" | |
3577 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
3578 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" | |
3579 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
3580 | " trace_clock\t\t-change the clock used to order events\n" | |
3581 | " local: Per cpu clock but may not be synced across CPUs\n" | |
3582 | " global: Synced across CPUs but slows tracing down.\n" | |
3583 | " counter: Not a clock, but just an increment\n" | |
3584 | " uptime: Jiffy counter from time of boot\n" | |
3585 | " perf: Same clock that perf events use\n" | |
3586 | #ifdef CONFIG_X86_64 | |
3587 | " x86-tsc: TSC cycle counter\n" | |
3588 | #endif | |
3589 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" | |
3590 | " tracing_cpumask\t- Limit which CPUs to trace\n" | |
3591 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
3592 | "\t\t\t Remove sub-buffer with rmdir\n" | |
3593 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
71485c45 SRRH |
3594 | "\t\t\t Disable an option by adding a suffix 'no' to the\n" |
3595 | "\t\t\t option name\n" | |
22f45649 SRRH |
3596 | #ifdef CONFIG_DYNAMIC_FTRACE |
3597 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
71485c45 SRRH |
3598 | " set_ftrace_filter\t- echo function name in here to only trace these\n" |
3599 | "\t\t\t functions\n" | |
3600 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3601 | "\t modules: Can select a group via module\n" | |
3602 | "\t Format: :mod:<module-name>\n" | |
3603 | "\t example: echo :mod:ext3 > set_ftrace_filter\n" | |
3604 | "\t triggers: a command to perform when function is hit\n" | |
3605 | "\t Format: <function>:<trigger>[:count]\n" | |
3606 | "\t trigger: traceon, traceoff\n" | |
3607 | "\t\t enable_event:<system>:<event>\n" | |
3608 | "\t\t disable_event:<system>:<event>\n" | |
22f45649 | 3609 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3610 | "\t\t stacktrace\n" |
22f45649 SRRH |
3611 | #endif |
3612 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3613 | "\t\t snapshot\n" |
22f45649 | 3614 | #endif |
17a280ea SRRH |
3615 | "\t\t dump\n" |
3616 | "\t\t cpudump\n" | |
71485c45 SRRH |
3617 | "\t example: echo do_fault:traceoff > set_ftrace_filter\n" |
3618 | "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
3619 | "\t The first one will disable tracing every time do_fault is hit\n" | |
3620 | "\t The second will disable tracing at most 3 times when do_trap is hit\n" | |
3621 | "\t The first time do trap is hit and it disables tracing, the\n" | |
3622 | "\t counter will decrement to 2. If tracing is already disabled,\n" | |
3623 | "\t the counter will not decrement. It only decrements when the\n" | |
3624 | "\t trigger did work\n" | |
3625 | "\t To remove trigger without count:\n" | |
3626 | "\t echo '!<function>:<trigger> > set_ftrace_filter\n" | |
3627 | "\t To remove trigger with a count:\n" | |
3628 | "\t echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
22f45649 | 3629 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" |
71485c45 SRRH |
3630 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" |
3631 | "\t modules: Can select a group via module command :mod:\n" | |
3632 | "\t Does not accept triggers\n" | |
22f45649 SRRH |
3633 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
3634 | #ifdef CONFIG_FUNCTION_TRACER | |
71485c45 SRRH |
3635 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" |
3636 | "\t\t (function)\n" | |
22f45649 SRRH |
3637 | #endif |
3638 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
3639 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
3640 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" | |
3641 | #endif | |
3642 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 SRRH |
3643 | "\n snapshot\t\t- Like 'trace' but shows the content of the static\n" |
3644 | "\t\t\t snapshot buffer. Read the contents for more\n" | |
3645 | "\t\t\t information\n" | |
22f45649 | 3646 | #endif |
991821c8 | 3647 | #ifdef CONFIG_STACK_TRACER |
22f45649 SRRH |
3648 | " stack_trace\t\t- Shows the max stack trace when active\n" |
3649 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
71485c45 SRRH |
3650 | "\t\t\t Write into this file to reset the max size (trigger a\n" |
3651 | "\t\t\t new trace)\n" | |
22f45649 | 3652 | #ifdef CONFIG_DYNAMIC_FTRACE |
71485c45 SRRH |
3653 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n" |
3654 | "\t\t\t traces\n" | |
22f45649 | 3655 | #endif |
991821c8 | 3656 | #endif /* CONFIG_STACK_TRACER */ |
26f25564 TZ |
3657 | " events/\t\t- Directory containing all trace event subsystems:\n" |
3658 | " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" | |
3659 | " events/<system>/\t- Directory containing all trace events for <system>:\n" | |
71485c45 SRRH |
3660 | " enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n" |
3661 | "\t\t\t events\n" | |
26f25564 | 3662 | " filter\t\t- If set, only events passing filter are traced\n" |
71485c45 SRRH |
3663 | " events/<system>/<event>/\t- Directory containing control files for\n" |
3664 | "\t\t\t <event>:\n" | |
26f25564 TZ |
3665 | " enable\t\t- Write 0/1 to enable/disable tracing of <event>\n" |
3666 | " filter\t\t- If set, only events passing filter are traced\n" | |
3667 | " trigger\t\t- If set, a command to perform when event is hit\n" | |
71485c45 SRRH |
3668 | "\t Format: <trigger>[:count][if <filter>]\n" |
3669 | "\t trigger: traceon, traceoff\n" | |
3670 | "\t enable_event:<system>:<event>\n" | |
3671 | "\t disable_event:<system>:<event>\n" | |
26f25564 | 3672 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3673 | "\t\t stacktrace\n" |
26f25564 TZ |
3674 | #endif |
3675 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3676 | "\t\t snapshot\n" |
26f25564 | 3677 | #endif |
71485c45 SRRH |
3678 | "\t example: echo traceoff > events/block/block_unplug/trigger\n" |
3679 | "\t echo traceoff:3 > events/block/block_unplug/trigger\n" | |
3680 | "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" | |
3681 | "\t events/block/block_unplug/trigger\n" | |
3682 | "\t The first disables tracing every time block_unplug is hit.\n" | |
3683 | "\t The second disables tracing the first 3 times block_unplug is hit.\n" | |
3684 | "\t The third enables the kmalloc event the first 3 times block_unplug\n" | |
3685 | "\t is hit and has value of greater than 1 for the 'nr_rq' event field.\n" | |
3686 | "\t Like function triggers, the counter is only decremented if it\n" | |
3687 | "\t enabled or disabled tracing.\n" | |
3688 | "\t To remove a trigger without a count:\n" | |
3689 | "\t echo '!<trigger> > <system>/<event>/trigger\n" | |
3690 | "\t To remove a trigger with a count:\n" | |
3691 | "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" | |
3692 | "\t Filters can be ignored when removing a trigger.\n" | |
7bd2f24c IM |
3693 | ; |
3694 | ||
3695 | static ssize_t | |
3696 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
3697 | size_t cnt, loff_t *ppos) | |
3698 | { | |
3699 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
3700 | readme_msg, strlen(readme_msg)); | |
3701 | } | |
3702 | ||
5e2336a0 | 3703 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
3704 | .open = tracing_open_generic, |
3705 | .read = tracing_readme_read, | |
b444786f | 3706 | .llseek = generic_file_llseek, |
7bd2f24c IM |
3707 | }; |
3708 | ||
42584c81 YY |
3709 | static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos) |
3710 | { | |
3711 | unsigned int *ptr = v; | |
69abe6a5 | 3712 | |
42584c81 YY |
3713 | if (*pos || m->count) |
3714 | ptr++; | |
69abe6a5 | 3715 | |
42584c81 | 3716 | (*pos)++; |
69abe6a5 | 3717 | |
42584c81 YY |
3718 | for (; ptr < &map_cmdline_to_pid[SAVED_CMDLINES]; ptr++) { |
3719 | if (*ptr == -1 || *ptr == NO_CMDLINE_MAP) | |
3720 | continue; | |
69abe6a5 | 3721 | |
42584c81 YY |
3722 | return ptr; |
3723 | } | |
69abe6a5 | 3724 | |
42584c81 YY |
3725 | return NULL; |
3726 | } | |
3727 | ||
3728 | static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos) | |
3729 | { | |
3730 | void *v; | |
3731 | loff_t l = 0; | |
69abe6a5 | 3732 | |
4c27e756 SRRH |
3733 | preempt_disable(); |
3734 | arch_spin_lock(&trace_cmdline_lock); | |
3735 | ||
42584c81 YY |
3736 | v = &map_cmdline_to_pid[0]; |
3737 | while (l <= *pos) { | |
3738 | v = saved_cmdlines_next(m, v, &l); | |
3739 | if (!v) | |
3740 | return NULL; | |
69abe6a5 AP |
3741 | } |
3742 | ||
42584c81 YY |
3743 | return v; |
3744 | } | |
3745 | ||
3746 | static void saved_cmdlines_stop(struct seq_file *m, void *v) | |
3747 | { | |
4c27e756 SRRH |
3748 | arch_spin_unlock(&trace_cmdline_lock); |
3749 | preempt_enable(); | |
42584c81 | 3750 | } |
69abe6a5 | 3751 | |
42584c81 YY |
3752 | static int saved_cmdlines_show(struct seq_file *m, void *v) |
3753 | { | |
3754 | char buf[TASK_COMM_LEN]; | |
3755 | unsigned int *pid = v; | |
69abe6a5 | 3756 | |
4c27e756 | 3757 | __trace_find_cmdline(*pid, buf); |
42584c81 YY |
3758 | seq_printf(m, "%d %s\n", *pid, buf); |
3759 | return 0; | |
3760 | } | |
3761 | ||
3762 | static const struct seq_operations tracing_saved_cmdlines_seq_ops = { | |
3763 | .start = saved_cmdlines_start, | |
3764 | .next = saved_cmdlines_next, | |
3765 | .stop = saved_cmdlines_stop, | |
3766 | .show = saved_cmdlines_show, | |
3767 | }; | |
3768 | ||
3769 | static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp) | |
3770 | { | |
3771 | if (tracing_disabled) | |
3772 | return -ENODEV; | |
3773 | ||
3774 | return seq_open(filp, &tracing_saved_cmdlines_seq_ops); | |
69abe6a5 AP |
3775 | } |
3776 | ||
3777 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
42584c81 YY |
3778 | .open = tracing_saved_cmdlines_open, |
3779 | .read = seq_read, | |
3780 | .llseek = seq_lseek, | |
3781 | .release = seq_release, | |
69abe6a5 AP |
3782 | }; |
3783 | ||
bc0c38d1 SR |
3784 | static ssize_t |
3785 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
3786 | size_t cnt, loff_t *ppos) | |
3787 | { | |
2b6080f2 | 3788 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 3789 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
3790 | int r; |
3791 | ||
3792 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 3793 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
3794 | mutex_unlock(&trace_types_lock); |
3795 | ||
4bf39a94 | 3796 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3797 | } |
3798 | ||
b6f11df2 ACM |
3799 | int tracer_init(struct tracer *t, struct trace_array *tr) |
3800 | { | |
12883efb | 3801 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
3802 | return t->init(tr); |
3803 | } | |
3804 | ||
12883efb | 3805 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
3806 | { |
3807 | int cpu; | |
737223fb | 3808 | |
438ced17 | 3809 | for_each_tracing_cpu(cpu) |
12883efb | 3810 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
3811 | } |
3812 | ||
12883efb | 3813 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 3814 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
3815 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
3816 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
3817 | { |
3818 | int cpu, ret = 0; | |
3819 | ||
3820 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
3821 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
3822 | ret = ring_buffer_resize(trace_buf->buffer, |
3823 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
3824 | if (ret < 0) |
3825 | break; | |
12883efb SRRH |
3826 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
3827 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
3828 | } |
3829 | } else { | |
12883efb SRRH |
3830 | ret = ring_buffer_resize(trace_buf->buffer, |
3831 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 3832 | if (ret == 0) |
12883efb SRRH |
3833 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
3834 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
3835 | } |
3836 | ||
3837 | return ret; | |
3838 | } | |
12883efb | 3839 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 3840 | |
2b6080f2 SR |
3841 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
3842 | unsigned long size, int cpu) | |
73c5162a SR |
3843 | { |
3844 | int ret; | |
3845 | ||
3846 | /* | |
3847 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3848 | * we use the size that was given, and we can forget about |
3849 | * expanding it later. | |
73c5162a | 3850 | */ |
55034cd6 | 3851 | ring_buffer_expanded = true; |
73c5162a | 3852 | |
b382ede6 | 3853 | /* May be called before buffers are initialized */ |
12883efb | 3854 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
3855 | return 0; |
3856 | ||
12883efb | 3857 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
3858 | if (ret < 0) |
3859 | return ret; | |
3860 | ||
12883efb | 3861 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
3862 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
3863 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
3864 | goto out; |
3865 | ||
12883efb | 3866 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 3867 | if (ret < 0) { |
12883efb SRRH |
3868 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
3869 | &tr->trace_buffer, cpu); | |
73c5162a | 3870 | if (r < 0) { |
a123c52b SR |
3871 | /* |
3872 | * AARGH! We are left with different | |
3873 | * size max buffer!!!! | |
3874 | * The max buffer is our "snapshot" buffer. | |
3875 | * When a tracer needs a snapshot (one of the | |
3876 | * latency tracers), it swaps the max buffer | |
3877 | * with the saved snap shot. We succeeded to | |
3878 | * update the size of the main buffer, but failed to | |
3879 | * update the size of the max buffer. But when we tried | |
3880 | * to reset the main buffer to the original size, we | |
3881 | * failed there too. This is very unlikely to | |
3882 | * happen, but if it does, warn and kill all | |
3883 | * tracing. | |
3884 | */ | |
73c5162a SR |
3885 | WARN_ON(1); |
3886 | tracing_disabled = 1; | |
3887 | } | |
3888 | return ret; | |
3889 | } | |
3890 | ||
438ced17 | 3891 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3892 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 3893 | else |
12883efb | 3894 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 3895 | |
ef710e10 | 3896 | out: |
12883efb SRRH |
3897 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
3898 | ||
438ced17 | 3899 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 3900 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 3901 | else |
12883efb | 3902 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
3903 | |
3904 | return ret; | |
3905 | } | |
3906 | ||
2b6080f2 SR |
3907 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
3908 | unsigned long size, int cpu_id) | |
4f271a2a | 3909 | { |
83f40318 | 3910 | int ret = size; |
4f271a2a VN |
3911 | |
3912 | mutex_lock(&trace_types_lock); | |
3913 | ||
438ced17 VN |
3914 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
3915 | /* make sure, this cpu is enabled in the mask */ | |
3916 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
3917 | ret = -EINVAL; | |
3918 | goto out; | |
3919 | } | |
3920 | } | |
4f271a2a | 3921 | |
2b6080f2 | 3922 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
3923 | if (ret < 0) |
3924 | ret = -ENOMEM; | |
3925 | ||
438ced17 | 3926 | out: |
4f271a2a VN |
3927 | mutex_unlock(&trace_types_lock); |
3928 | ||
3929 | return ret; | |
3930 | } | |
3931 | ||
ef710e10 | 3932 | |
1852fcce SR |
3933 | /** |
3934 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
3935 | * | |
3936 | * To save on memory when the tracing is never used on a system with it | |
3937 | * configured in. The ring buffers are set to a minimum size. But once | |
3938 | * a user starts to use the tracing facility, then they need to grow | |
3939 | * to their default size. | |
3940 | * | |
3941 | * This function is to be called when a tracer is about to be used. | |
3942 | */ | |
3943 | int tracing_update_buffers(void) | |
3944 | { | |
3945 | int ret = 0; | |
3946 | ||
1027fcb2 | 3947 | mutex_lock(&trace_types_lock); |
1852fcce | 3948 | if (!ring_buffer_expanded) |
2b6080f2 | 3949 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 3950 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 3951 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
3952 | |
3953 | return ret; | |
3954 | } | |
3955 | ||
577b785f SR |
3956 | struct trace_option_dentry; |
3957 | ||
3958 | static struct trace_option_dentry * | |
2b6080f2 | 3959 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f SR |
3960 | |
3961 | static void | |
3962 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
3963 | ||
6b450d25 SRRH |
3964 | /* |
3965 | * Used to clear out the tracer before deletion of an instance. | |
3966 | * Must have trace_types_lock held. | |
3967 | */ | |
3968 | static void tracing_set_nop(struct trace_array *tr) | |
3969 | { | |
3970 | if (tr->current_trace == &nop_trace) | |
3971 | return; | |
3972 | ||
50512ab5 | 3973 | tr->current_trace->enabled--; |
6b450d25 SRRH |
3974 | |
3975 | if (tr->current_trace->reset) | |
3976 | tr->current_trace->reset(tr); | |
3977 | ||
3978 | tr->current_trace = &nop_trace; | |
3979 | } | |
3980 | ||
607e2ea1 | 3981 | static int tracing_set_tracer(struct trace_array *tr, const char *buf) |
bc0c38d1 | 3982 | { |
577b785f | 3983 | static struct trace_option_dentry *topts; |
bc0c38d1 | 3984 | struct tracer *t; |
12883efb | 3985 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 3986 | bool had_max_tr; |
12883efb | 3987 | #endif |
d9e54076 | 3988 | int ret = 0; |
bc0c38d1 | 3989 | |
1027fcb2 SR |
3990 | mutex_lock(&trace_types_lock); |
3991 | ||
73c5162a | 3992 | if (!ring_buffer_expanded) { |
2b6080f2 | 3993 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 3994 | RING_BUFFER_ALL_CPUS); |
73c5162a | 3995 | if (ret < 0) |
59f586db | 3996 | goto out; |
73c5162a SR |
3997 | ret = 0; |
3998 | } | |
3999 | ||
bc0c38d1 SR |
4000 | for (t = trace_types; t; t = t->next) { |
4001 | if (strcmp(t->name, buf) == 0) | |
4002 | break; | |
4003 | } | |
c2931e05 FW |
4004 | if (!t) { |
4005 | ret = -EINVAL; | |
4006 | goto out; | |
4007 | } | |
2b6080f2 | 4008 | if (t == tr->current_trace) |
bc0c38d1 SR |
4009 | goto out; |
4010 | ||
607e2ea1 SRRH |
4011 | /* Some tracers are only allowed for the top level buffer */ |
4012 | if (!trace_ok_for_array(t, tr)) { | |
4013 | ret = -EINVAL; | |
4014 | goto out; | |
4015 | } | |
4016 | ||
9f029e83 | 4017 | trace_branch_disable(); |
613f04a0 | 4018 | |
50512ab5 | 4019 | tr->current_trace->enabled--; |
613f04a0 | 4020 | |
2b6080f2 SR |
4021 | if (tr->current_trace->reset) |
4022 | tr->current_trace->reset(tr); | |
34600f0e | 4023 | |
12883efb | 4024 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 4025 | tr->current_trace = &nop_trace; |
34600f0e | 4026 | |
45ad21ca SRRH |
4027 | #ifdef CONFIG_TRACER_MAX_TRACE |
4028 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
4029 | |
4030 | if (had_max_tr && !t->use_max_tr) { | |
4031 | /* | |
4032 | * We need to make sure that the update_max_tr sees that | |
4033 | * current_trace changed to nop_trace to keep it from | |
4034 | * swapping the buffers after we resize it. | |
4035 | * The update_max_tr is called from interrupts disabled | |
4036 | * so a synchronized_sched() is sufficient. | |
4037 | */ | |
4038 | synchronize_sched(); | |
3209cff4 | 4039 | free_snapshot(tr); |
ef710e10 | 4040 | } |
12883efb | 4041 | #endif |
f1b21c9a SRRH |
4042 | /* Currently, only the top instance has options */ |
4043 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) { | |
4044 | destroy_trace_option_files(topts); | |
4045 | topts = create_trace_option_files(tr, t); | |
4046 | } | |
12883efb SRRH |
4047 | |
4048 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 4049 | if (t->use_max_tr && !had_max_tr) { |
3209cff4 | 4050 | ret = alloc_snapshot(tr); |
d60da506 HT |
4051 | if (ret < 0) |
4052 | goto out; | |
ef710e10 | 4053 | } |
12883efb | 4054 | #endif |
577b785f | 4055 | |
1c80025a | 4056 | if (t->init) { |
b6f11df2 | 4057 | ret = tracer_init(t, tr); |
1c80025a FW |
4058 | if (ret) |
4059 | goto out; | |
4060 | } | |
bc0c38d1 | 4061 | |
2b6080f2 | 4062 | tr->current_trace = t; |
50512ab5 | 4063 | tr->current_trace->enabled++; |
9f029e83 | 4064 | trace_branch_enable(tr); |
bc0c38d1 SR |
4065 | out: |
4066 | mutex_unlock(&trace_types_lock); | |
4067 | ||
d9e54076 PZ |
4068 | return ret; |
4069 | } | |
4070 | ||
4071 | static ssize_t | |
4072 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
4073 | size_t cnt, loff_t *ppos) | |
4074 | { | |
607e2ea1 | 4075 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 4076 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
4077 | int i; |
4078 | size_t ret; | |
e6e7a65a FW |
4079 | int err; |
4080 | ||
4081 | ret = cnt; | |
d9e54076 | 4082 | |
ee6c2c1b LZ |
4083 | if (cnt > MAX_TRACER_SIZE) |
4084 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
4085 | |
4086 | if (copy_from_user(&buf, ubuf, cnt)) | |
4087 | return -EFAULT; | |
4088 | ||
4089 | buf[cnt] = 0; | |
4090 | ||
4091 | /* strip ending whitespace. */ | |
4092 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
4093 | buf[i] = 0; | |
4094 | ||
607e2ea1 | 4095 | err = tracing_set_tracer(tr, buf); |
e6e7a65a FW |
4096 | if (err) |
4097 | return err; | |
d9e54076 | 4098 | |
cf8517cf | 4099 | *ppos += ret; |
bc0c38d1 | 4100 | |
c2931e05 | 4101 | return ret; |
bc0c38d1 SR |
4102 | } |
4103 | ||
4104 | static ssize_t | |
4105 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
4106 | size_t cnt, loff_t *ppos) | |
4107 | { | |
4108 | unsigned long *ptr = filp->private_data; | |
4109 | char buf[64]; | |
4110 | int r; | |
4111 | ||
cffae437 | 4112 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 4113 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
4114 | if (r > sizeof(buf)) |
4115 | r = sizeof(buf); | |
4bf39a94 | 4116 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
4117 | } |
4118 | ||
4119 | static ssize_t | |
4120 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
4121 | size_t cnt, loff_t *ppos) | |
4122 | { | |
5e39841c | 4123 | unsigned long *ptr = filp->private_data; |
5e39841c | 4124 | unsigned long val; |
c6caeeb1 | 4125 | int ret; |
bc0c38d1 | 4126 | |
22fe9b54 PH |
4127 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4128 | if (ret) | |
c6caeeb1 | 4129 | return ret; |
bc0c38d1 SR |
4130 | |
4131 | *ptr = val * 1000; | |
4132 | ||
4133 | return cnt; | |
4134 | } | |
4135 | ||
b3806b43 SR |
4136 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
4137 | { | |
15544209 | 4138 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4139 | struct trace_iterator *iter; |
b04cc6b1 | 4140 | int ret = 0; |
b3806b43 SR |
4141 | |
4142 | if (tracing_disabled) | |
4143 | return -ENODEV; | |
4144 | ||
7b85af63 SRRH |
4145 | if (trace_array_get(tr) < 0) |
4146 | return -ENODEV; | |
4147 | ||
b04cc6b1 FW |
4148 | mutex_lock(&trace_types_lock); |
4149 | ||
b3806b43 SR |
4150 | /* create a buffer to store the information to pass to userspace */ |
4151 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
4152 | if (!iter) { |
4153 | ret = -ENOMEM; | |
f77d09a3 | 4154 | __trace_array_put(tr); |
b04cc6b1 FW |
4155 | goto out; |
4156 | } | |
b3806b43 | 4157 | |
d7350c3f FW |
4158 | /* |
4159 | * We make a copy of the current tracer to avoid concurrent | |
4160 | * changes on it while we are reading. | |
4161 | */ | |
4162 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
4163 | if (!iter->trace) { | |
4164 | ret = -ENOMEM; | |
4165 | goto fail; | |
4166 | } | |
2b6080f2 | 4167 | *iter->trace = *tr->current_trace; |
d7350c3f | 4168 | |
4462344e | 4169 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 4170 | ret = -ENOMEM; |
d7350c3f | 4171 | goto fail; |
4462344e RR |
4172 | } |
4173 | ||
a309720c | 4174 | /* trace pipe does not show start of buffer */ |
4462344e | 4175 | cpumask_setall(iter->started); |
a309720c | 4176 | |
112f38a7 SR |
4177 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
4178 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
4179 | ||
8be0709f | 4180 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 4181 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
4182 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
4183 | ||
15544209 ON |
4184 | iter->tr = tr; |
4185 | iter->trace_buffer = &tr->trace_buffer; | |
4186 | iter->cpu_file = tracing_get_cpu(inode); | |
d7350c3f | 4187 | mutex_init(&iter->mutex); |
b3806b43 SR |
4188 | filp->private_data = iter; |
4189 | ||
107bad8b SR |
4190 | if (iter->trace->pipe_open) |
4191 | iter->trace->pipe_open(iter); | |
107bad8b | 4192 | |
b444786f | 4193 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
4194 | out: |
4195 | mutex_unlock(&trace_types_lock); | |
4196 | return ret; | |
d7350c3f FW |
4197 | |
4198 | fail: | |
4199 | kfree(iter->trace); | |
4200 | kfree(iter); | |
7b85af63 | 4201 | __trace_array_put(tr); |
d7350c3f FW |
4202 | mutex_unlock(&trace_types_lock); |
4203 | return ret; | |
b3806b43 SR |
4204 | } |
4205 | ||
4206 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
4207 | { | |
4208 | struct trace_iterator *iter = file->private_data; | |
15544209 | 4209 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4210 | |
b04cc6b1 FW |
4211 | mutex_lock(&trace_types_lock); |
4212 | ||
29bf4a5e | 4213 | if (iter->trace->pipe_close) |
c521efd1 SR |
4214 | iter->trace->pipe_close(iter); |
4215 | ||
b04cc6b1 FW |
4216 | mutex_unlock(&trace_types_lock); |
4217 | ||
4462344e | 4218 | free_cpumask_var(iter->started); |
d7350c3f FW |
4219 | mutex_destroy(&iter->mutex); |
4220 | kfree(iter->trace); | |
b3806b43 | 4221 | kfree(iter); |
b3806b43 | 4222 | |
7b85af63 SRRH |
4223 | trace_array_put(tr); |
4224 | ||
b3806b43 SR |
4225 | return 0; |
4226 | } | |
4227 | ||
2a2cc8f7 | 4228 | static unsigned int |
cc60cdc9 | 4229 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 4230 | { |
15693458 SRRH |
4231 | /* Iterators are static, they should be filled or empty */ |
4232 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
4233 | return POLLIN | POLLRDNORM; | |
2a2cc8f7 | 4234 | |
15693458 | 4235 | if (trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
4236 | /* |
4237 | * Always select as readable when in blocking mode | |
4238 | */ | |
4239 | return POLLIN | POLLRDNORM; | |
15693458 | 4240 | else |
12883efb | 4241 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 4242 | filp, poll_table); |
2a2cc8f7 | 4243 | } |
2a2cc8f7 | 4244 | |
cc60cdc9 SR |
4245 | static unsigned int |
4246 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
4247 | { | |
4248 | struct trace_iterator *iter = filp->private_data; | |
4249 | ||
4250 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
4251 | } |
4252 | ||
ff98781b EGM |
4253 | /* Must be called with trace_types_lock mutex held. */ |
4254 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
4255 | { |
4256 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 4257 | |
b3806b43 | 4258 | while (trace_empty(iter)) { |
2dc8f095 | 4259 | |
107bad8b | 4260 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 4261 | return -EAGAIN; |
107bad8b | 4262 | } |
2dc8f095 | 4263 | |
b3806b43 | 4264 | /* |
250bfd3d | 4265 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
4266 | * We still block if tracing is disabled, but we have never |
4267 | * read anything. This allows a user to cat this file, and | |
4268 | * then enable tracing. But after we have read something, | |
4269 | * we give an EOF when tracing is again disabled. | |
4270 | * | |
4271 | * iter->pos will be 0 if we haven't read anything. | |
4272 | */ | |
10246fa3 | 4273 | if (!tracing_is_on() && iter->pos) |
b3806b43 | 4274 | break; |
f4874261 SRRH |
4275 | |
4276 | mutex_unlock(&iter->mutex); | |
4277 | ||
b1169cc6 | 4278 | wait_on_pipe(iter); |
f4874261 SRRH |
4279 | |
4280 | mutex_lock(&iter->mutex); | |
4281 | ||
4282 | if (signal_pending(current)) | |
4283 | return -EINTR; | |
b3806b43 SR |
4284 | } |
4285 | ||
ff98781b EGM |
4286 | return 1; |
4287 | } | |
4288 | ||
4289 | /* | |
4290 | * Consumer reader. | |
4291 | */ | |
4292 | static ssize_t | |
4293 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
4294 | size_t cnt, loff_t *ppos) | |
4295 | { | |
4296 | struct trace_iterator *iter = filp->private_data; | |
2b6080f2 | 4297 | struct trace_array *tr = iter->tr; |
ff98781b EGM |
4298 | ssize_t sret; |
4299 | ||
4300 | /* return any leftover data */ | |
4301 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
4302 | if (sret != -EBUSY) | |
4303 | return sret; | |
4304 | ||
f9520750 | 4305 | trace_seq_init(&iter->seq); |
ff98781b | 4306 | |
d7350c3f | 4307 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 4308 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4309 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4310 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4311 | mutex_unlock(&trace_types_lock); |
4312 | ||
4313 | /* | |
4314 | * Avoid more than one consumer on a single file descriptor | |
4315 | * This is just a matter of traces coherency, the ring buffer itself | |
4316 | * is protected. | |
4317 | */ | |
4318 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
4319 | if (iter->trace->read) { |
4320 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
4321 | if (sret) | |
4322 | goto out; | |
4323 | } | |
4324 | ||
4325 | waitagain: | |
4326 | sret = tracing_wait_pipe(filp); | |
4327 | if (sret <= 0) | |
4328 | goto out; | |
4329 | ||
b3806b43 | 4330 | /* stop when tracing is finished */ |
ff98781b EGM |
4331 | if (trace_empty(iter)) { |
4332 | sret = 0; | |
107bad8b | 4333 | goto out; |
ff98781b | 4334 | } |
b3806b43 SR |
4335 | |
4336 | if (cnt >= PAGE_SIZE) | |
4337 | cnt = PAGE_SIZE - 1; | |
4338 | ||
53d0aa77 | 4339 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
4340 | memset(&iter->seq, 0, |
4341 | sizeof(struct trace_iterator) - | |
4342 | offsetof(struct trace_iterator, seq)); | |
ed5467da | 4343 | cpumask_clear(iter->started); |
4823ed7e | 4344 | iter->pos = -1; |
b3806b43 | 4345 | |
4f535968 | 4346 | trace_event_read_lock(); |
7e53bd42 | 4347 | trace_access_lock(iter->cpu_file); |
955b61e5 | 4348 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 4349 | enum print_line_t ret; |
088b1e42 SR |
4350 | int len = iter->seq.len; |
4351 | ||
f9896bf3 | 4352 | ret = print_trace_line(iter); |
2c4f035f | 4353 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
4354 | /* don't print partial lines */ |
4355 | iter->seq.len = len; | |
b3806b43 | 4356 | break; |
088b1e42 | 4357 | } |
b91facc3 FW |
4358 | if (ret != TRACE_TYPE_NO_CONSUME) |
4359 | trace_consume(iter); | |
b3806b43 SR |
4360 | |
4361 | if (iter->seq.len >= cnt) | |
4362 | break; | |
ee5e51f5 JO |
4363 | |
4364 | /* | |
4365 | * Setting the full flag means we reached the trace_seq buffer | |
4366 | * size and we should leave by partial output condition above. | |
4367 | * One of the trace_seq_* functions is not used properly. | |
4368 | */ | |
4369 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
4370 | iter->ent->type); | |
b3806b43 | 4371 | } |
7e53bd42 | 4372 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4373 | trace_event_read_unlock(); |
b3806b43 | 4374 | |
b3806b43 | 4375 | /* Now copy what we have to the user */ |
6c6c2796 PP |
4376 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
4377 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 4378 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
4379 | |
4380 | /* | |
25985edc | 4381 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
4382 | * entries, go back to wait for more entries. |
4383 | */ | |
6c6c2796 | 4384 | if (sret == -EBUSY) |
9ff4b974 | 4385 | goto waitagain; |
b3806b43 | 4386 | |
107bad8b | 4387 | out: |
d7350c3f | 4388 | mutex_unlock(&iter->mutex); |
107bad8b | 4389 | |
6c6c2796 | 4390 | return sret; |
b3806b43 SR |
4391 | } |
4392 | ||
3c56819b EGM |
4393 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, |
4394 | unsigned int idx) | |
4395 | { | |
4396 | __free_page(spd->pages[idx]); | |
4397 | } | |
4398 | ||
28dfef8f | 4399 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 | 4400 | .can_merge = 0, |
34cd4998 | 4401 | .confirm = generic_pipe_buf_confirm, |
92fdd98c | 4402 | .release = generic_pipe_buf_release, |
34cd4998 SR |
4403 | .steal = generic_pipe_buf_steal, |
4404 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
4405 | }; |
4406 | ||
34cd4998 | 4407 | static size_t |
fa7c7f6e | 4408 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
4409 | { |
4410 | size_t count; | |
4411 | int ret; | |
4412 | ||
4413 | /* Seq buffer is page-sized, exactly what we need. */ | |
4414 | for (;;) { | |
4415 | count = iter->seq.len; | |
4416 | ret = print_trace_line(iter); | |
4417 | count = iter->seq.len - count; | |
4418 | if (rem < count) { | |
4419 | rem = 0; | |
4420 | iter->seq.len -= count; | |
4421 | break; | |
4422 | } | |
4423 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
4424 | iter->seq.len -= count; | |
4425 | break; | |
4426 | } | |
4427 | ||
74e7ff8c LJ |
4428 | if (ret != TRACE_TYPE_NO_CONSUME) |
4429 | trace_consume(iter); | |
34cd4998 | 4430 | rem -= count; |
955b61e5 | 4431 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
4432 | rem = 0; |
4433 | iter->ent = NULL; | |
4434 | break; | |
4435 | } | |
4436 | } | |
4437 | ||
4438 | return rem; | |
4439 | } | |
4440 | ||
3c56819b EGM |
4441 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
4442 | loff_t *ppos, | |
4443 | struct pipe_inode_info *pipe, | |
4444 | size_t len, | |
4445 | unsigned int flags) | |
4446 | { | |
35f3d14d JA |
4447 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
4448 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
4449 | struct trace_iterator *iter = filp->private_data; |
4450 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
4451 | .pages = pages_def, |
4452 | .partial = partial_def, | |
34cd4998 | 4453 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 4454 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
4455 | .flags = flags, |
4456 | .ops = &tracing_pipe_buf_ops, | |
4457 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 4458 | }; |
2b6080f2 | 4459 | struct trace_array *tr = iter->tr; |
3c56819b | 4460 | ssize_t ret; |
34cd4998 | 4461 | size_t rem; |
3c56819b EGM |
4462 | unsigned int i; |
4463 | ||
35f3d14d JA |
4464 | if (splice_grow_spd(pipe, &spd)) |
4465 | return -ENOMEM; | |
4466 | ||
d7350c3f | 4467 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 4468 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
4469 | if (unlikely(iter->trace->name != tr->current_trace->name)) |
4470 | *iter->trace = *tr->current_trace; | |
d7350c3f FW |
4471 | mutex_unlock(&trace_types_lock); |
4472 | ||
4473 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
4474 | |
4475 | if (iter->trace->splice_read) { | |
4476 | ret = iter->trace->splice_read(iter, filp, | |
4477 | ppos, pipe, len, flags); | |
4478 | if (ret) | |
34cd4998 | 4479 | goto out_err; |
3c56819b EGM |
4480 | } |
4481 | ||
4482 | ret = tracing_wait_pipe(filp); | |
4483 | if (ret <= 0) | |
34cd4998 | 4484 | goto out_err; |
3c56819b | 4485 | |
955b61e5 | 4486 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 4487 | ret = -EFAULT; |
34cd4998 | 4488 | goto out_err; |
3c56819b EGM |
4489 | } |
4490 | ||
4f535968 | 4491 | trace_event_read_lock(); |
7e53bd42 | 4492 | trace_access_lock(iter->cpu_file); |
4f535968 | 4493 | |
3c56819b | 4494 | /* Fill as many pages as possible. */ |
a786c06d | 4495 | for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) { |
35f3d14d JA |
4496 | spd.pages[i] = alloc_page(GFP_KERNEL); |
4497 | if (!spd.pages[i]) | |
34cd4998 | 4498 | break; |
3c56819b | 4499 | |
fa7c7f6e | 4500 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
4501 | |
4502 | /* Copy the data into the page, so we can start over. */ | |
4503 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 4504 | page_address(spd.pages[i]), |
3c56819b EGM |
4505 | iter->seq.len); |
4506 | if (ret < 0) { | |
35f3d14d | 4507 | __free_page(spd.pages[i]); |
3c56819b EGM |
4508 | break; |
4509 | } | |
35f3d14d JA |
4510 | spd.partial[i].offset = 0; |
4511 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 4512 | |
f9520750 | 4513 | trace_seq_init(&iter->seq); |
3c56819b EGM |
4514 | } |
4515 | ||
7e53bd42 | 4516 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4517 | trace_event_read_unlock(); |
d7350c3f | 4518 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
4519 | |
4520 | spd.nr_pages = i; | |
4521 | ||
35f3d14d JA |
4522 | ret = splice_to_pipe(pipe, &spd); |
4523 | out: | |
047fe360 | 4524 | splice_shrink_spd(&spd); |
35f3d14d | 4525 | return ret; |
3c56819b | 4526 | |
34cd4998 | 4527 | out_err: |
d7350c3f | 4528 | mutex_unlock(&iter->mutex); |
35f3d14d | 4529 | goto out; |
3c56819b EGM |
4530 | } |
4531 | ||
a98a3c3f SR |
4532 | static ssize_t |
4533 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
4534 | size_t cnt, loff_t *ppos) | |
4535 | { | |
0bc392ee ON |
4536 | struct inode *inode = file_inode(filp); |
4537 | struct trace_array *tr = inode->i_private; | |
4538 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
4539 | char buf[64]; |
4540 | int r = 0; | |
4541 | ssize_t ret; | |
a98a3c3f | 4542 | |
db526ca3 | 4543 | mutex_lock(&trace_types_lock); |
438ced17 | 4544 | |
0bc392ee | 4545 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
4546 | int cpu, buf_size_same; |
4547 | unsigned long size; | |
4548 | ||
4549 | size = 0; | |
4550 | buf_size_same = 1; | |
4551 | /* check if all cpu sizes are same */ | |
4552 | for_each_tracing_cpu(cpu) { | |
4553 | /* fill in the size from first enabled cpu */ | |
4554 | if (size == 0) | |
12883efb SRRH |
4555 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
4556 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
4557 | buf_size_same = 0; |
4558 | break; | |
4559 | } | |
4560 | } | |
4561 | ||
4562 | if (buf_size_same) { | |
4563 | if (!ring_buffer_expanded) | |
4564 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
4565 | size >> 10, | |
4566 | trace_buf_size >> 10); | |
4567 | else | |
4568 | r = sprintf(buf, "%lu\n", size >> 10); | |
4569 | } else | |
4570 | r = sprintf(buf, "X\n"); | |
4571 | } else | |
0bc392ee | 4572 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10); |
438ced17 | 4573 | |
db526ca3 SR |
4574 | mutex_unlock(&trace_types_lock); |
4575 | ||
438ced17 VN |
4576 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
4577 | return ret; | |
a98a3c3f SR |
4578 | } |
4579 | ||
4580 | static ssize_t | |
4581 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
4582 | size_t cnt, loff_t *ppos) | |
4583 | { | |
0bc392ee ON |
4584 | struct inode *inode = file_inode(filp); |
4585 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 4586 | unsigned long val; |
4f271a2a | 4587 | int ret; |
a98a3c3f | 4588 | |
22fe9b54 PH |
4589 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4590 | if (ret) | |
c6caeeb1 | 4591 | return ret; |
a98a3c3f SR |
4592 | |
4593 | /* must have at least 1 entry */ | |
4594 | if (!val) | |
4595 | return -EINVAL; | |
4596 | ||
1696b2b0 SR |
4597 | /* value is in KB */ |
4598 | val <<= 10; | |
0bc392ee | 4599 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
4600 | if (ret < 0) |
4601 | return ret; | |
a98a3c3f | 4602 | |
cf8517cf | 4603 | *ppos += cnt; |
a98a3c3f | 4604 | |
4f271a2a VN |
4605 | return cnt; |
4606 | } | |
bf5e6519 | 4607 | |
f81ab074 VN |
4608 | static ssize_t |
4609 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
4610 | size_t cnt, loff_t *ppos) | |
4611 | { | |
4612 | struct trace_array *tr = filp->private_data; | |
4613 | char buf[64]; | |
4614 | int r, cpu; | |
4615 | unsigned long size = 0, expanded_size = 0; | |
4616 | ||
4617 | mutex_lock(&trace_types_lock); | |
4618 | for_each_tracing_cpu(cpu) { | |
12883efb | 4619 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
4620 | if (!ring_buffer_expanded) |
4621 | expanded_size += trace_buf_size >> 10; | |
4622 | } | |
4623 | if (ring_buffer_expanded) | |
4624 | r = sprintf(buf, "%lu\n", size); | |
4625 | else | |
4626 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
4627 | mutex_unlock(&trace_types_lock); | |
4628 | ||
4629 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4630 | } | |
4631 | ||
4f271a2a VN |
4632 | static ssize_t |
4633 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
4634 | size_t cnt, loff_t *ppos) | |
4635 | { | |
4636 | /* | |
4637 | * There is no need to read what the user has written, this function | |
4638 | * is just to make sure that there is no error when "echo" is used | |
4639 | */ | |
4640 | ||
4641 | *ppos += cnt; | |
a98a3c3f SR |
4642 | |
4643 | return cnt; | |
4644 | } | |
4645 | ||
4f271a2a VN |
4646 | static int |
4647 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
4648 | { | |
2b6080f2 SR |
4649 | struct trace_array *tr = inode->i_private; |
4650 | ||
cf30cf67 SR |
4651 | /* disable tracing ? */ |
4652 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
711e1243 | 4653 | tracer_tracing_off(tr); |
4f271a2a | 4654 | /* resize the ring buffer to 0 */ |
2b6080f2 | 4655 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 4656 | |
7b85af63 SRRH |
4657 | trace_array_put(tr); |
4658 | ||
4f271a2a VN |
4659 | return 0; |
4660 | } | |
4661 | ||
5bf9a1ee PP |
4662 | static ssize_t |
4663 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
4664 | size_t cnt, loff_t *fpos) | |
4665 | { | |
d696b58c | 4666 | unsigned long addr = (unsigned long)ubuf; |
2d71619c | 4667 | struct trace_array *tr = filp->private_data; |
d696b58c SR |
4668 | struct ring_buffer_event *event; |
4669 | struct ring_buffer *buffer; | |
4670 | struct print_entry *entry; | |
4671 | unsigned long irq_flags; | |
4672 | struct page *pages[2]; | |
6edb2a8a | 4673 | void *map_page[2]; |
d696b58c SR |
4674 | int nr_pages = 1; |
4675 | ssize_t written; | |
d696b58c SR |
4676 | int offset; |
4677 | int size; | |
4678 | int len; | |
4679 | int ret; | |
6edb2a8a | 4680 | int i; |
5bf9a1ee | 4681 | |
c76f0694 | 4682 | if (tracing_disabled) |
5bf9a1ee PP |
4683 | return -EINVAL; |
4684 | ||
5224c3a3 MSB |
4685 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
4686 | return -EINVAL; | |
4687 | ||
5bf9a1ee PP |
4688 | if (cnt > TRACE_BUF_SIZE) |
4689 | cnt = TRACE_BUF_SIZE; | |
4690 | ||
d696b58c SR |
4691 | /* |
4692 | * Userspace is injecting traces into the kernel trace buffer. | |
4693 | * We want to be as non intrusive as possible. | |
4694 | * To do so, we do not want to allocate any special buffers | |
4695 | * or take any locks, but instead write the userspace data | |
4696 | * straight into the ring buffer. | |
4697 | * | |
4698 | * First we need to pin the userspace buffer into memory, | |
4699 | * which, most likely it is, because it just referenced it. | |
4700 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
4701 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
4702 | * pages directly. We then write the data directly into the | |
4703 | * ring buffer. | |
4704 | */ | |
4705 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 4706 | |
d696b58c SR |
4707 | /* check if we cross pages */ |
4708 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
4709 | nr_pages = 2; | |
4710 | ||
4711 | offset = addr & (PAGE_SIZE - 1); | |
4712 | addr &= PAGE_MASK; | |
4713 | ||
4714 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
4715 | if (ret < nr_pages) { | |
4716 | while (--ret >= 0) | |
4717 | put_page(pages[ret]); | |
4718 | written = -EFAULT; | |
4719 | goto out; | |
5bf9a1ee | 4720 | } |
d696b58c | 4721 | |
6edb2a8a SR |
4722 | for (i = 0; i < nr_pages; i++) |
4723 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
4724 | |
4725 | local_save_flags(irq_flags); | |
4726 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
2d71619c | 4727 | buffer = tr->trace_buffer.buffer; |
d696b58c SR |
4728 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
4729 | irq_flags, preempt_count()); | |
4730 | if (!event) { | |
4731 | /* Ring buffer disabled, return as if not open for write */ | |
4732 | written = -EBADF; | |
4733 | goto out_unlock; | |
5bf9a1ee | 4734 | } |
d696b58c SR |
4735 | |
4736 | entry = ring_buffer_event_data(event); | |
4737 | entry->ip = _THIS_IP_; | |
4738 | ||
4739 | if (nr_pages == 2) { | |
4740 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
4741 | memcpy(&entry->buf, map_page[0] + offset, len); |
4742 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 4743 | } else |
6edb2a8a | 4744 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 4745 | |
d696b58c SR |
4746 | if (entry->buf[cnt - 1] != '\n') { |
4747 | entry->buf[cnt] = '\n'; | |
4748 | entry->buf[cnt + 1] = '\0'; | |
4749 | } else | |
4750 | entry->buf[cnt] = '\0'; | |
4751 | ||
7ffbd48d | 4752 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 4753 | |
d696b58c | 4754 | written = cnt; |
5bf9a1ee | 4755 | |
d696b58c | 4756 | *fpos += written; |
1aa54bca | 4757 | |
d696b58c | 4758 | out_unlock: |
6edb2a8a SR |
4759 | for (i = 0; i < nr_pages; i++){ |
4760 | kunmap_atomic(map_page[i]); | |
4761 | put_page(pages[i]); | |
4762 | } | |
d696b58c | 4763 | out: |
1aa54bca | 4764 | return written; |
5bf9a1ee PP |
4765 | } |
4766 | ||
13f16d20 | 4767 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 4768 | { |
2b6080f2 | 4769 | struct trace_array *tr = m->private; |
5079f326 Z |
4770 | int i; |
4771 | ||
4772 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 4773 | seq_printf(m, |
5079f326 | 4774 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
4775 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
4776 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 4777 | seq_putc(m, '\n'); |
5079f326 | 4778 | |
13f16d20 | 4779 | return 0; |
5079f326 Z |
4780 | } |
4781 | ||
e1e232ca | 4782 | static int tracing_set_clock(struct trace_array *tr, const char *clockstr) |
5079f326 | 4783 | { |
5079f326 Z |
4784 | int i; |
4785 | ||
5079f326 Z |
4786 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { |
4787 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
4788 | break; | |
4789 | } | |
4790 | if (i == ARRAY_SIZE(trace_clocks)) | |
4791 | return -EINVAL; | |
4792 | ||
5079f326 Z |
4793 | mutex_lock(&trace_types_lock); |
4794 | ||
2b6080f2 SR |
4795 | tr->clock_id = i; |
4796 | ||
12883efb | 4797 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 4798 | |
60303ed3 DS |
4799 | /* |
4800 | * New clock may not be consistent with the previous clock. | |
4801 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
4802 | */ | |
9457158b | 4803 | tracing_reset_online_cpus(&tr->trace_buffer); |
12883efb SRRH |
4804 | |
4805 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4806 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) | |
4807 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); | |
9457158b | 4808 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 4809 | #endif |
60303ed3 | 4810 | |
5079f326 Z |
4811 | mutex_unlock(&trace_types_lock); |
4812 | ||
e1e232ca SR |
4813 | return 0; |
4814 | } | |
4815 | ||
4816 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
4817 | size_t cnt, loff_t *fpos) | |
4818 | { | |
4819 | struct seq_file *m = filp->private_data; | |
4820 | struct trace_array *tr = m->private; | |
4821 | char buf[64]; | |
4822 | const char *clockstr; | |
4823 | int ret; | |
4824 | ||
4825 | if (cnt >= sizeof(buf)) | |
4826 | return -EINVAL; | |
4827 | ||
4828 | if (copy_from_user(&buf, ubuf, cnt)) | |
4829 | return -EFAULT; | |
4830 | ||
4831 | buf[cnt] = 0; | |
4832 | ||
4833 | clockstr = strstrip(buf); | |
4834 | ||
4835 | ret = tracing_set_clock(tr, clockstr); | |
4836 | if (ret) | |
4837 | return ret; | |
4838 | ||
5079f326 Z |
4839 | *fpos += cnt; |
4840 | ||
4841 | return cnt; | |
4842 | } | |
4843 | ||
13f16d20 LZ |
4844 | static int tracing_clock_open(struct inode *inode, struct file *file) |
4845 | { | |
7b85af63 SRRH |
4846 | struct trace_array *tr = inode->i_private; |
4847 | int ret; | |
4848 | ||
13f16d20 LZ |
4849 | if (tracing_disabled) |
4850 | return -ENODEV; | |
2b6080f2 | 4851 | |
7b85af63 SRRH |
4852 | if (trace_array_get(tr)) |
4853 | return -ENODEV; | |
4854 | ||
4855 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
4856 | if (ret < 0) | |
4857 | trace_array_put(tr); | |
4858 | ||
4859 | return ret; | |
13f16d20 LZ |
4860 | } |
4861 | ||
6de58e62 SRRH |
4862 | struct ftrace_buffer_info { |
4863 | struct trace_iterator iter; | |
4864 | void *spare; | |
4865 | unsigned int read; | |
4866 | }; | |
4867 | ||
debdd57f HT |
4868 | #ifdef CONFIG_TRACER_SNAPSHOT |
4869 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
4870 | { | |
6484c71c | 4871 | struct trace_array *tr = inode->i_private; |
debdd57f | 4872 | struct trace_iterator *iter; |
2b6080f2 | 4873 | struct seq_file *m; |
debdd57f HT |
4874 | int ret = 0; |
4875 | ||
ff451961 SRRH |
4876 | if (trace_array_get(tr) < 0) |
4877 | return -ENODEV; | |
4878 | ||
debdd57f | 4879 | if (file->f_mode & FMODE_READ) { |
6484c71c | 4880 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
4881 | if (IS_ERR(iter)) |
4882 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
4883 | } else { |
4884 | /* Writes still need the seq_file to hold the private data */ | |
f77d09a3 | 4885 | ret = -ENOMEM; |
2b6080f2 SR |
4886 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
4887 | if (!m) | |
f77d09a3 | 4888 | goto out; |
2b6080f2 SR |
4889 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
4890 | if (!iter) { | |
4891 | kfree(m); | |
f77d09a3 | 4892 | goto out; |
2b6080f2 | 4893 | } |
f77d09a3 AL |
4894 | ret = 0; |
4895 | ||
ff451961 | 4896 | iter->tr = tr; |
6484c71c ON |
4897 | iter->trace_buffer = &tr->max_buffer; |
4898 | iter->cpu_file = tracing_get_cpu(inode); | |
2b6080f2 SR |
4899 | m->private = iter; |
4900 | file->private_data = m; | |
debdd57f | 4901 | } |
f77d09a3 | 4902 | out: |
ff451961 SRRH |
4903 | if (ret < 0) |
4904 | trace_array_put(tr); | |
4905 | ||
debdd57f HT |
4906 | return ret; |
4907 | } | |
4908 | ||
4909 | static ssize_t | |
4910 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4911 | loff_t *ppos) | |
4912 | { | |
2b6080f2 SR |
4913 | struct seq_file *m = filp->private_data; |
4914 | struct trace_iterator *iter = m->private; | |
4915 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
4916 | unsigned long val; |
4917 | int ret; | |
4918 | ||
4919 | ret = tracing_update_buffers(); | |
4920 | if (ret < 0) | |
4921 | return ret; | |
4922 | ||
4923 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
4924 | if (ret) | |
4925 | return ret; | |
4926 | ||
4927 | mutex_lock(&trace_types_lock); | |
4928 | ||
2b6080f2 | 4929 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
4930 | ret = -EBUSY; |
4931 | goto out; | |
4932 | } | |
4933 | ||
4934 | switch (val) { | |
4935 | case 0: | |
f1affcaa SRRH |
4936 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
4937 | ret = -EINVAL; | |
4938 | break; | |
debdd57f | 4939 | } |
3209cff4 SRRH |
4940 | if (tr->allocated_snapshot) |
4941 | free_snapshot(tr); | |
debdd57f HT |
4942 | break; |
4943 | case 1: | |
f1affcaa SRRH |
4944 | /* Only allow per-cpu swap if the ring buffer supports it */ |
4945 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
4946 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
4947 | ret = -EINVAL; | |
4948 | break; | |
4949 | } | |
4950 | #endif | |
45ad21ca | 4951 | if (!tr->allocated_snapshot) { |
3209cff4 | 4952 | ret = alloc_snapshot(tr); |
debdd57f HT |
4953 | if (ret < 0) |
4954 | break; | |
debdd57f | 4955 | } |
debdd57f HT |
4956 | local_irq_disable(); |
4957 | /* Now, we're going to swap */ | |
f1affcaa | 4958 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 4959 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 4960 | else |
ce9bae55 | 4961 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
4962 | local_irq_enable(); |
4963 | break; | |
4964 | default: | |
45ad21ca | 4965 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
4966 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
4967 | tracing_reset_online_cpus(&tr->max_buffer); | |
4968 | else | |
4969 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
4970 | } | |
debdd57f HT |
4971 | break; |
4972 | } | |
4973 | ||
4974 | if (ret >= 0) { | |
4975 | *ppos += cnt; | |
4976 | ret = cnt; | |
4977 | } | |
4978 | out: | |
4979 | mutex_unlock(&trace_types_lock); | |
4980 | return ret; | |
4981 | } | |
2b6080f2 SR |
4982 | |
4983 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
4984 | { | |
4985 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
4986 | int ret; |
4987 | ||
4988 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
4989 | |
4990 | if (file->f_mode & FMODE_READ) | |
ff451961 | 4991 | return ret; |
2b6080f2 SR |
4992 | |
4993 | /* If write only, the seq_file is just a stub */ | |
4994 | if (m) | |
4995 | kfree(m->private); | |
4996 | kfree(m); | |
4997 | ||
4998 | return 0; | |
4999 | } | |
5000 | ||
6de58e62 SRRH |
5001 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
5002 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5003 | size_t count, loff_t *ppos); | |
5004 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
5005 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5006 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
5007 | ||
5008 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
5009 | { | |
5010 | struct ftrace_buffer_info *info; | |
5011 | int ret; | |
5012 | ||
5013 | ret = tracing_buffers_open(inode, filp); | |
5014 | if (ret < 0) | |
5015 | return ret; | |
5016 | ||
5017 | info = filp->private_data; | |
5018 | ||
5019 | if (info->iter.trace->use_max_tr) { | |
5020 | tracing_buffers_release(inode, filp); | |
5021 | return -EBUSY; | |
5022 | } | |
5023 | ||
5024 | info->iter.snapshot = true; | |
5025 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
5026 | ||
5027 | return ret; | |
5028 | } | |
5029 | ||
debdd57f HT |
5030 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5031 | ||
5032 | ||
5e2336a0 | 5033 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
5034 | .open = tracing_open_generic, |
5035 | .read = tracing_max_lat_read, | |
5036 | .write = tracing_max_lat_write, | |
b444786f | 5037 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5038 | }; |
5039 | ||
5e2336a0 | 5040 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
5041 | .open = tracing_open_generic, |
5042 | .read = tracing_set_trace_read, | |
5043 | .write = tracing_set_trace_write, | |
b444786f | 5044 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5045 | }; |
5046 | ||
5e2336a0 | 5047 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 5048 | .open = tracing_open_pipe, |
2a2cc8f7 | 5049 | .poll = tracing_poll_pipe, |
4bf39a94 | 5050 | .read = tracing_read_pipe, |
3c56819b | 5051 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 5052 | .release = tracing_release_pipe, |
b444786f | 5053 | .llseek = no_llseek, |
b3806b43 SR |
5054 | }; |
5055 | ||
5e2336a0 | 5056 | static const struct file_operations tracing_entries_fops = { |
0bc392ee | 5057 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
5058 | .read = tracing_entries_read, |
5059 | .write = tracing_entries_write, | |
b444786f | 5060 | .llseek = generic_file_llseek, |
0bc392ee | 5061 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
5062 | }; |
5063 | ||
f81ab074 | 5064 | static const struct file_operations tracing_total_entries_fops = { |
7b85af63 | 5065 | .open = tracing_open_generic_tr, |
f81ab074 VN |
5066 | .read = tracing_total_entries_read, |
5067 | .llseek = generic_file_llseek, | |
7b85af63 | 5068 | .release = tracing_release_generic_tr, |
f81ab074 VN |
5069 | }; |
5070 | ||
4f271a2a | 5071 | static const struct file_operations tracing_free_buffer_fops = { |
7b85af63 | 5072 | .open = tracing_open_generic_tr, |
4f271a2a VN |
5073 | .write = tracing_free_buffer_write, |
5074 | .release = tracing_free_buffer_release, | |
5075 | }; | |
5076 | ||
5e2336a0 | 5077 | static const struct file_operations tracing_mark_fops = { |
7b85af63 | 5078 | .open = tracing_open_generic_tr, |
5bf9a1ee | 5079 | .write = tracing_mark_write, |
b444786f | 5080 | .llseek = generic_file_llseek, |
7b85af63 | 5081 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
5082 | }; |
5083 | ||
5079f326 | 5084 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
5085 | .open = tracing_clock_open, |
5086 | .read = seq_read, | |
5087 | .llseek = seq_lseek, | |
7b85af63 | 5088 | .release = tracing_single_release_tr, |
5079f326 Z |
5089 | .write = tracing_clock_write, |
5090 | }; | |
5091 | ||
debdd57f HT |
5092 | #ifdef CONFIG_TRACER_SNAPSHOT |
5093 | static const struct file_operations snapshot_fops = { | |
5094 | .open = tracing_snapshot_open, | |
5095 | .read = seq_read, | |
5096 | .write = tracing_snapshot_write, | |
098c879e | 5097 | .llseek = tracing_lseek, |
2b6080f2 | 5098 | .release = tracing_snapshot_release, |
debdd57f | 5099 | }; |
debdd57f | 5100 | |
6de58e62 SRRH |
5101 | static const struct file_operations snapshot_raw_fops = { |
5102 | .open = snapshot_raw_open, | |
5103 | .read = tracing_buffers_read, | |
5104 | .release = tracing_buffers_release, | |
5105 | .splice_read = tracing_buffers_splice_read, | |
5106 | .llseek = no_llseek, | |
2cadf913 SR |
5107 | }; |
5108 | ||
6de58e62 SRRH |
5109 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5110 | ||
2cadf913 SR |
5111 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
5112 | { | |
46ef2be0 | 5113 | struct trace_array *tr = inode->i_private; |
2cadf913 | 5114 | struct ftrace_buffer_info *info; |
7b85af63 | 5115 | int ret; |
2cadf913 SR |
5116 | |
5117 | if (tracing_disabled) | |
5118 | return -ENODEV; | |
5119 | ||
7b85af63 SRRH |
5120 | if (trace_array_get(tr) < 0) |
5121 | return -ENODEV; | |
5122 | ||
2cadf913 | 5123 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
7b85af63 SRRH |
5124 | if (!info) { |
5125 | trace_array_put(tr); | |
2cadf913 | 5126 | return -ENOMEM; |
7b85af63 | 5127 | } |
2cadf913 | 5128 | |
a695cb58 SRRH |
5129 | mutex_lock(&trace_types_lock); |
5130 | ||
cc60cdc9 | 5131 | info->iter.tr = tr; |
46ef2be0 | 5132 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 5133 | info->iter.trace = tr->current_trace; |
12883efb | 5134 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 5135 | info->spare = NULL; |
2cadf913 | 5136 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 5137 | info->read = (unsigned int)-1; |
2cadf913 SR |
5138 | |
5139 | filp->private_data = info; | |
5140 | ||
a695cb58 SRRH |
5141 | mutex_unlock(&trace_types_lock); |
5142 | ||
7b85af63 SRRH |
5143 | ret = nonseekable_open(inode, filp); |
5144 | if (ret < 0) | |
5145 | trace_array_put(tr); | |
5146 | ||
5147 | return ret; | |
2cadf913 SR |
5148 | } |
5149 | ||
cc60cdc9 SR |
5150 | static unsigned int |
5151 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
5152 | { | |
5153 | struct ftrace_buffer_info *info = filp->private_data; | |
5154 | struct trace_iterator *iter = &info->iter; | |
5155 | ||
5156 | return trace_poll(iter, filp, poll_table); | |
5157 | } | |
5158 | ||
2cadf913 SR |
5159 | static ssize_t |
5160 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5161 | size_t count, loff_t *ppos) | |
5162 | { | |
5163 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 5164 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5165 | ssize_t ret; |
6de58e62 | 5166 | ssize_t size; |
2cadf913 | 5167 | |
2dc5d12b SR |
5168 | if (!count) |
5169 | return 0; | |
5170 | ||
6de58e62 SRRH |
5171 | mutex_lock(&trace_types_lock); |
5172 | ||
5173 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5174 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
5175 | size = -EBUSY; | |
5176 | goto out_unlock; | |
5177 | } | |
5178 | #endif | |
5179 | ||
ddd538f3 | 5180 | if (!info->spare) |
12883efb SRRH |
5181 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
5182 | iter->cpu_file); | |
6de58e62 | 5183 | size = -ENOMEM; |
ddd538f3 | 5184 | if (!info->spare) |
6de58e62 | 5185 | goto out_unlock; |
ddd538f3 | 5186 | |
2cadf913 SR |
5187 | /* Do we have previous read data to read? */ |
5188 | if (info->read < PAGE_SIZE) | |
5189 | goto read; | |
5190 | ||
b627344f | 5191 | again: |
cc60cdc9 | 5192 | trace_access_lock(iter->cpu_file); |
12883efb | 5193 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
5194 | &info->spare, |
5195 | count, | |
cc60cdc9 SR |
5196 | iter->cpu_file, 0); |
5197 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 5198 | |
b627344f SR |
5199 | if (ret < 0) { |
5200 | if (trace_empty(iter)) { | |
6de58e62 SRRH |
5201 | if ((filp->f_flags & O_NONBLOCK)) { |
5202 | size = -EAGAIN; | |
5203 | goto out_unlock; | |
5204 | } | |
5205 | mutex_unlock(&trace_types_lock); | |
b1169cc6 | 5206 | wait_on_pipe(iter); |
6de58e62 SRRH |
5207 | mutex_lock(&trace_types_lock); |
5208 | if (signal_pending(current)) { | |
5209 | size = -EINTR; | |
5210 | goto out_unlock; | |
5211 | } | |
b627344f SR |
5212 | goto again; |
5213 | } | |
6de58e62 SRRH |
5214 | size = 0; |
5215 | goto out_unlock; | |
b627344f | 5216 | } |
436fc280 | 5217 | |
436fc280 | 5218 | info->read = 0; |
b627344f | 5219 | read: |
2cadf913 SR |
5220 | size = PAGE_SIZE - info->read; |
5221 | if (size > count) | |
5222 | size = count; | |
5223 | ||
5224 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
6de58e62 SRRH |
5225 | if (ret == size) { |
5226 | size = -EFAULT; | |
5227 | goto out_unlock; | |
5228 | } | |
2dc5d12b SR |
5229 | size -= ret; |
5230 | ||
2cadf913 SR |
5231 | *ppos += size; |
5232 | info->read += size; | |
5233 | ||
6de58e62 SRRH |
5234 | out_unlock: |
5235 | mutex_unlock(&trace_types_lock); | |
5236 | ||
2cadf913 SR |
5237 | return size; |
5238 | } | |
5239 | ||
5240 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
5241 | { | |
5242 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5243 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5244 | |
a695cb58 SRRH |
5245 | mutex_lock(&trace_types_lock); |
5246 | ||
ff451961 | 5247 | __trace_array_put(iter->tr); |
2cadf913 | 5248 | |
ddd538f3 | 5249 | if (info->spare) |
12883efb | 5250 | ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); |
2cadf913 SR |
5251 | kfree(info); |
5252 | ||
a695cb58 SRRH |
5253 | mutex_unlock(&trace_types_lock); |
5254 | ||
2cadf913 SR |
5255 | return 0; |
5256 | } | |
5257 | ||
5258 | struct buffer_ref { | |
5259 | struct ring_buffer *buffer; | |
5260 | void *page; | |
5261 | int ref; | |
5262 | }; | |
5263 | ||
5264 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
5265 | struct pipe_buffer *buf) | |
5266 | { | |
5267 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5268 | ||
5269 | if (--ref->ref) | |
5270 | return; | |
5271 | ||
5272 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5273 | kfree(ref); | |
5274 | buf->private = 0; | |
5275 | } | |
5276 | ||
2cadf913 SR |
5277 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
5278 | struct pipe_buffer *buf) | |
5279 | { | |
5280 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5281 | ||
5282 | ref->ref++; | |
5283 | } | |
5284 | ||
5285 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 5286 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 | 5287 | .can_merge = 0, |
2cadf913 SR |
5288 | .confirm = generic_pipe_buf_confirm, |
5289 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 5290 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
5291 | .get = buffer_pipe_buf_get, |
5292 | }; | |
5293 | ||
5294 | /* | |
5295 | * Callback from splice_to_pipe(), if we need to release some pages | |
5296 | * at the end of the spd in case we error'ed out in filling the pipe. | |
5297 | */ | |
5298 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
5299 | { | |
5300 | struct buffer_ref *ref = | |
5301 | (struct buffer_ref *)spd->partial[i].private; | |
5302 | ||
5303 | if (--ref->ref) | |
5304 | return; | |
5305 | ||
5306 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5307 | kfree(ref); | |
5308 | spd->partial[i].private = 0; | |
5309 | } | |
5310 | ||
5311 | static ssize_t | |
5312 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5313 | struct pipe_inode_info *pipe, size_t len, | |
5314 | unsigned int flags) | |
5315 | { | |
5316 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5317 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
5318 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
5319 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 5320 | struct splice_pipe_desc spd = { |
35f3d14d JA |
5321 | .pages = pages_def, |
5322 | .partial = partial_def, | |
047fe360 | 5323 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
5324 | .flags = flags, |
5325 | .ops = &buffer_pipe_buf_ops, | |
5326 | .spd_release = buffer_spd_release, | |
5327 | }; | |
5328 | struct buffer_ref *ref; | |
93459c6c | 5329 | int entries, size, i; |
6de58e62 | 5330 | ssize_t ret; |
2cadf913 | 5331 | |
6de58e62 SRRH |
5332 | mutex_lock(&trace_types_lock); |
5333 | ||
5334 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5335 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) { | |
5336 | ret = -EBUSY; | |
5337 | goto out; | |
5338 | } | |
5339 | #endif | |
5340 | ||
5341 | if (splice_grow_spd(pipe, &spd)) { | |
5342 | ret = -ENOMEM; | |
5343 | goto out; | |
5344 | } | |
35f3d14d | 5345 | |
93cfb3c9 | 5346 | if (*ppos & (PAGE_SIZE - 1)) { |
35f3d14d JA |
5347 | ret = -EINVAL; |
5348 | goto out; | |
93cfb3c9 LJ |
5349 | } |
5350 | ||
5351 | if (len & (PAGE_SIZE - 1)) { | |
35f3d14d JA |
5352 | if (len < PAGE_SIZE) { |
5353 | ret = -EINVAL; | |
5354 | goto out; | |
5355 | } | |
93cfb3c9 LJ |
5356 | len &= PAGE_MASK; |
5357 | } | |
5358 | ||
cc60cdc9 SR |
5359 | again: |
5360 | trace_access_lock(iter->cpu_file); | |
12883efb | 5361 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 5362 | |
a786c06d | 5363 | for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
5364 | struct page *page; |
5365 | int r; | |
5366 | ||
5367 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
5368 | if (!ref) | |
5369 | break; | |
5370 | ||
7267fa68 | 5371 | ref->ref = 1; |
12883efb | 5372 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 5373 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
2cadf913 SR |
5374 | if (!ref->page) { |
5375 | kfree(ref); | |
5376 | break; | |
5377 | } | |
5378 | ||
5379 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 5380 | len, iter->cpu_file, 1); |
2cadf913 | 5381 | if (r < 0) { |
7ea59064 | 5382 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
5383 | kfree(ref); |
5384 | break; | |
5385 | } | |
5386 | ||
5387 | /* | |
5388 | * zero out any left over data, this is going to | |
5389 | * user land. | |
5390 | */ | |
5391 | size = ring_buffer_page_len(ref->page); | |
5392 | if (size < PAGE_SIZE) | |
5393 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
5394 | ||
5395 | page = virt_to_page(ref->page); | |
5396 | ||
5397 | spd.pages[i] = page; | |
5398 | spd.partial[i].len = PAGE_SIZE; | |
5399 | spd.partial[i].offset = 0; | |
5400 | spd.partial[i].private = (unsigned long)ref; | |
5401 | spd.nr_pages++; | |
93cfb3c9 | 5402 | *ppos += PAGE_SIZE; |
93459c6c | 5403 | |
12883efb | 5404 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
5405 | } |
5406 | ||
cc60cdc9 | 5407 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
5408 | spd.nr_pages = i; |
5409 | ||
5410 | /* did we read anything? */ | |
5411 | if (!spd.nr_pages) { | |
cc60cdc9 | 5412 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) { |
2cadf913 | 5413 | ret = -EAGAIN; |
cc60cdc9 SR |
5414 | goto out; |
5415 | } | |
6de58e62 | 5416 | mutex_unlock(&trace_types_lock); |
b1169cc6 | 5417 | wait_on_pipe(iter); |
6de58e62 | 5418 | mutex_lock(&trace_types_lock); |
cc60cdc9 SR |
5419 | if (signal_pending(current)) { |
5420 | ret = -EINTR; | |
5421 | goto out; | |
5422 | } | |
5423 | goto again; | |
2cadf913 SR |
5424 | } |
5425 | ||
5426 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 5427 | splice_shrink_spd(&spd); |
35f3d14d | 5428 | out: |
6de58e62 SRRH |
5429 | mutex_unlock(&trace_types_lock); |
5430 | ||
2cadf913 SR |
5431 | return ret; |
5432 | } | |
5433 | ||
5434 | static const struct file_operations tracing_buffers_fops = { | |
5435 | .open = tracing_buffers_open, | |
5436 | .read = tracing_buffers_read, | |
cc60cdc9 | 5437 | .poll = tracing_buffers_poll, |
2cadf913 SR |
5438 | .release = tracing_buffers_release, |
5439 | .splice_read = tracing_buffers_splice_read, | |
5440 | .llseek = no_llseek, | |
5441 | }; | |
5442 | ||
c8d77183 SR |
5443 | static ssize_t |
5444 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
5445 | size_t count, loff_t *ppos) | |
5446 | { | |
4d3435b8 ON |
5447 | struct inode *inode = file_inode(filp); |
5448 | struct trace_array *tr = inode->i_private; | |
12883efb | 5449 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
4d3435b8 | 5450 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
5451 | struct trace_seq *s; |
5452 | unsigned long cnt; | |
c64e148a VN |
5453 | unsigned long long t; |
5454 | unsigned long usec_rem; | |
c8d77183 | 5455 | |
e4f2d10f | 5456 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 5457 | if (!s) |
a646365c | 5458 | return -ENOMEM; |
c8d77183 SR |
5459 | |
5460 | trace_seq_init(s); | |
5461 | ||
12883efb | 5462 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5463 | trace_seq_printf(s, "entries: %ld\n", cnt); |
5464 | ||
12883efb | 5465 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5466 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
5467 | ||
12883efb | 5468 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5469 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
5470 | ||
12883efb | 5471 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
5472 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
5473 | ||
58e8eedf | 5474 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 5475 | /* local or global for trace_clock */ |
12883efb | 5476 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
5477 | usec_rem = do_div(t, USEC_PER_SEC); |
5478 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
5479 | t, usec_rem); | |
5480 | ||
12883efb | 5481 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
5482 | usec_rem = do_div(t, USEC_PER_SEC); |
5483 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
5484 | } else { | |
5485 | /* counter or tsc mode for trace_clock */ | |
5486 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 5487 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 5488 | |
11043d8b | 5489 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 5490 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 5491 | } |
c64e148a | 5492 | |
12883efb | 5493 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
5494 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
5495 | ||
12883efb | 5496 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
5497 | trace_seq_printf(s, "read events: %ld\n", cnt); |
5498 | ||
c8d77183 SR |
5499 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
5500 | ||
5501 | kfree(s); | |
5502 | ||
5503 | return count; | |
5504 | } | |
5505 | ||
5506 | static const struct file_operations tracing_stats_fops = { | |
4d3435b8 | 5507 | .open = tracing_open_generic_tr, |
c8d77183 | 5508 | .read = tracing_stats_read, |
b444786f | 5509 | .llseek = generic_file_llseek, |
4d3435b8 | 5510 | .release = tracing_release_generic_tr, |
c8d77183 SR |
5511 | }; |
5512 | ||
bc0c38d1 SR |
5513 | #ifdef CONFIG_DYNAMIC_FTRACE |
5514 | ||
b807c3d0 SR |
5515 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
5516 | { | |
5517 | return 0; | |
5518 | } | |
5519 | ||
bc0c38d1 | 5520 | static ssize_t |
b807c3d0 | 5521 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
5522 | size_t cnt, loff_t *ppos) |
5523 | { | |
a26a2a27 SR |
5524 | static char ftrace_dyn_info_buffer[1024]; |
5525 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 5526 | unsigned long *p = filp->private_data; |
b807c3d0 | 5527 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 5528 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
5529 | int r; |
5530 | ||
b807c3d0 SR |
5531 | mutex_lock(&dyn_info_mutex); |
5532 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 5533 | |
a26a2a27 | 5534 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
5535 | buf[r++] = '\n'; |
5536 | ||
5537 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5538 | ||
5539 | mutex_unlock(&dyn_info_mutex); | |
5540 | ||
5541 | return r; | |
bc0c38d1 SR |
5542 | } |
5543 | ||
5e2336a0 | 5544 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 5545 | .open = tracing_open_generic, |
b807c3d0 | 5546 | .read = tracing_read_dyn_info, |
b444786f | 5547 | .llseek = generic_file_llseek, |
bc0c38d1 | 5548 | }; |
77fd5c15 | 5549 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 5550 | |
77fd5c15 SRRH |
5551 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
5552 | static void | |
5553 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
5554 | { | |
5555 | tracing_snapshot(); | |
5556 | } | |
bc0c38d1 | 5557 | |
77fd5c15 SRRH |
5558 | static void |
5559 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
bc0c38d1 | 5560 | { |
77fd5c15 SRRH |
5561 | unsigned long *count = (long *)data; |
5562 | ||
5563 | if (!*count) | |
5564 | return; | |
bc0c38d1 | 5565 | |
77fd5c15 SRRH |
5566 | if (*count != -1) |
5567 | (*count)--; | |
5568 | ||
5569 | tracing_snapshot(); | |
5570 | } | |
5571 | ||
5572 | static int | |
5573 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
5574 | struct ftrace_probe_ops *ops, void *data) | |
5575 | { | |
5576 | long count = (long)data; | |
5577 | ||
5578 | seq_printf(m, "%ps:", (void *)ip); | |
5579 | ||
5580 | seq_printf(m, "snapshot"); | |
5581 | ||
5582 | if (count == -1) | |
5583 | seq_printf(m, ":unlimited\n"); | |
5584 | else | |
5585 | seq_printf(m, ":count=%ld\n", count); | |
5586 | ||
5587 | return 0; | |
5588 | } | |
5589 | ||
5590 | static struct ftrace_probe_ops snapshot_probe_ops = { | |
5591 | .func = ftrace_snapshot, | |
5592 | .print = ftrace_snapshot_print, | |
5593 | }; | |
5594 | ||
5595 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
5596 | .func = ftrace_count_snapshot, | |
5597 | .print = ftrace_snapshot_print, | |
5598 | }; | |
5599 | ||
5600 | static int | |
5601 | ftrace_trace_snapshot_callback(struct ftrace_hash *hash, | |
5602 | char *glob, char *cmd, char *param, int enable) | |
5603 | { | |
5604 | struct ftrace_probe_ops *ops; | |
5605 | void *count = (void *)-1; | |
5606 | char *number; | |
5607 | int ret; | |
5608 | ||
5609 | /* hash funcs only work with set_ftrace_filter */ | |
5610 | if (!enable) | |
5611 | return -EINVAL; | |
5612 | ||
5613 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
5614 | ||
5615 | if (glob[0] == '!') { | |
5616 | unregister_ftrace_function_probe_func(glob+1, ops); | |
5617 | return 0; | |
5618 | } | |
5619 | ||
5620 | if (!param) | |
5621 | goto out_reg; | |
5622 | ||
5623 | number = strsep(¶m, ":"); | |
5624 | ||
5625 | if (!strlen(number)) | |
5626 | goto out_reg; | |
5627 | ||
5628 | /* | |
5629 | * We use the callback data field (which is a pointer) | |
5630 | * as our counter. | |
5631 | */ | |
5632 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
5633 | if (ret) | |
5634 | return ret; | |
5635 | ||
5636 | out_reg: | |
5637 | ret = register_ftrace_function_probe(glob, ops, count); | |
5638 | ||
5639 | if (ret >= 0) | |
5640 | alloc_snapshot(&global_trace); | |
5641 | ||
5642 | return ret < 0 ? ret : 0; | |
5643 | } | |
5644 | ||
5645 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
5646 | .name = "snapshot", | |
5647 | .func = ftrace_trace_snapshot_callback, | |
5648 | }; | |
5649 | ||
38de93ab | 5650 | static __init int register_snapshot_cmd(void) |
77fd5c15 SRRH |
5651 | { |
5652 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
5653 | } | |
5654 | #else | |
38de93ab | 5655 | static inline __init int register_snapshot_cmd(void) { return 0; } |
77fd5c15 | 5656 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ |
bc0c38d1 | 5657 | |
2b6080f2 | 5658 | struct dentry *tracing_init_dentry_tr(struct trace_array *tr) |
bc0c38d1 | 5659 | { |
2b6080f2 SR |
5660 | if (tr->dir) |
5661 | return tr->dir; | |
bc0c38d1 | 5662 | |
3e1f60b8 FW |
5663 | if (!debugfs_initialized()) |
5664 | return NULL; | |
5665 | ||
2b6080f2 SR |
5666 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) |
5667 | tr->dir = debugfs_create_dir("tracing", NULL); | |
bc0c38d1 | 5668 | |
687c878a J |
5669 | if (!tr->dir) |
5670 | pr_warn_once("Could not create debugfs directory 'tracing'\n"); | |
bc0c38d1 | 5671 | |
2b6080f2 | 5672 | return tr->dir; |
bc0c38d1 SR |
5673 | } |
5674 | ||
2b6080f2 SR |
5675 | struct dentry *tracing_init_dentry(void) |
5676 | { | |
5677 | return tracing_init_dentry_tr(&global_trace); | |
5678 | } | |
b04cc6b1 | 5679 | |
2b6080f2 | 5680 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 5681 | { |
b04cc6b1 FW |
5682 | struct dentry *d_tracer; |
5683 | ||
2b6080f2 SR |
5684 | if (tr->percpu_dir) |
5685 | return tr->percpu_dir; | |
b04cc6b1 | 5686 | |
2b6080f2 | 5687 | d_tracer = tracing_init_dentry_tr(tr); |
b04cc6b1 FW |
5688 | if (!d_tracer) |
5689 | return NULL; | |
5690 | ||
2b6080f2 | 5691 | tr->percpu_dir = debugfs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 5692 | |
2b6080f2 SR |
5693 | WARN_ONCE(!tr->percpu_dir, |
5694 | "Could not create debugfs directory 'per_cpu/%d'\n", cpu); | |
b04cc6b1 | 5695 | |
2b6080f2 | 5696 | return tr->percpu_dir; |
b04cc6b1 FW |
5697 | } |
5698 | ||
649e9c70 ON |
5699 | static struct dentry * |
5700 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
5701 | void *data, long cpu, const struct file_operations *fops) | |
5702 | { | |
5703 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
5704 | ||
5705 | if (ret) /* See tracing_get_cpu() */ | |
5706 | ret->d_inode->i_cdev = (void *)(cpu + 1); | |
5707 | return ret; | |
5708 | } | |
5709 | ||
2b6080f2 SR |
5710 | static void |
5711 | tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) | |
b04cc6b1 | 5712 | { |
2b6080f2 | 5713 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 5714 | struct dentry *d_cpu; |
dd49a38c | 5715 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 5716 | |
0a3d7ce7 NK |
5717 | if (!d_percpu) |
5718 | return; | |
5719 | ||
dd49a38c | 5720 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
5721 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
5722 | if (!d_cpu) { | |
5723 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
5724 | return; | |
5725 | } | |
b04cc6b1 | 5726 | |
8656e7a2 | 5727 | /* per cpu trace_pipe */ |
649e9c70 | 5728 | trace_create_cpu_file("trace_pipe", 0444, d_cpu, |
15544209 | 5729 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
5730 | |
5731 | /* per cpu trace */ | |
649e9c70 | 5732 | trace_create_cpu_file("trace", 0644, d_cpu, |
6484c71c | 5733 | tr, cpu, &tracing_fops); |
7f96f93f | 5734 | |
649e9c70 | 5735 | trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, |
46ef2be0 | 5736 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 5737 | |
649e9c70 | 5738 | trace_create_cpu_file("stats", 0444, d_cpu, |
4d3435b8 | 5739 | tr, cpu, &tracing_stats_fops); |
438ced17 | 5740 | |
649e9c70 | 5741 | trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, |
0bc392ee | 5742 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
5743 | |
5744 | #ifdef CONFIG_TRACER_SNAPSHOT | |
649e9c70 | 5745 | trace_create_cpu_file("snapshot", 0644, d_cpu, |
6484c71c | 5746 | tr, cpu, &snapshot_fops); |
6de58e62 | 5747 | |
649e9c70 | 5748 | trace_create_cpu_file("snapshot_raw", 0444, d_cpu, |
46ef2be0 | 5749 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 5750 | #endif |
b04cc6b1 FW |
5751 | } |
5752 | ||
60a11774 SR |
5753 | #ifdef CONFIG_FTRACE_SELFTEST |
5754 | /* Let selftest have access to static functions in this file */ | |
5755 | #include "trace_selftest.c" | |
5756 | #endif | |
5757 | ||
577b785f SR |
5758 | struct trace_option_dentry { |
5759 | struct tracer_opt *opt; | |
5760 | struct tracer_flags *flags; | |
2b6080f2 | 5761 | struct trace_array *tr; |
577b785f SR |
5762 | struct dentry *entry; |
5763 | }; | |
5764 | ||
5765 | static ssize_t | |
5766 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5767 | loff_t *ppos) | |
5768 | { | |
5769 | struct trace_option_dentry *topt = filp->private_data; | |
5770 | char *buf; | |
5771 | ||
5772 | if (topt->flags->val & topt->opt->bit) | |
5773 | buf = "1\n"; | |
5774 | else | |
5775 | buf = "0\n"; | |
5776 | ||
5777 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5778 | } | |
5779 | ||
5780 | static ssize_t | |
5781 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5782 | loff_t *ppos) | |
5783 | { | |
5784 | struct trace_option_dentry *topt = filp->private_data; | |
5785 | unsigned long val; | |
577b785f SR |
5786 | int ret; |
5787 | ||
22fe9b54 PH |
5788 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5789 | if (ret) | |
577b785f SR |
5790 | return ret; |
5791 | ||
8d18eaaf LZ |
5792 | if (val != 0 && val != 1) |
5793 | return -EINVAL; | |
577b785f | 5794 | |
8d18eaaf | 5795 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 5796 | mutex_lock(&trace_types_lock); |
8c1a49ae | 5797 | ret = __set_tracer_option(topt->tr, topt->flags, |
c757bea9 | 5798 | topt->opt, !val); |
577b785f SR |
5799 | mutex_unlock(&trace_types_lock); |
5800 | if (ret) | |
5801 | return ret; | |
577b785f SR |
5802 | } |
5803 | ||
5804 | *ppos += cnt; | |
5805 | ||
5806 | return cnt; | |
5807 | } | |
5808 | ||
5809 | ||
5810 | static const struct file_operations trace_options_fops = { | |
5811 | .open = tracing_open_generic, | |
5812 | .read = trace_options_read, | |
5813 | .write = trace_options_write, | |
b444786f | 5814 | .llseek = generic_file_llseek, |
577b785f SR |
5815 | }; |
5816 | ||
a8259075 SR |
5817 | static ssize_t |
5818 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5819 | loff_t *ppos) | |
5820 | { | |
5821 | long index = (long)filp->private_data; | |
5822 | char *buf; | |
5823 | ||
5824 | if (trace_flags & (1 << index)) | |
5825 | buf = "1\n"; | |
5826 | else | |
5827 | buf = "0\n"; | |
5828 | ||
5829 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5830 | } | |
5831 | ||
5832 | static ssize_t | |
5833 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5834 | loff_t *ppos) | |
5835 | { | |
2b6080f2 | 5836 | struct trace_array *tr = &global_trace; |
a8259075 | 5837 | long index = (long)filp->private_data; |
a8259075 SR |
5838 | unsigned long val; |
5839 | int ret; | |
5840 | ||
22fe9b54 PH |
5841 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5842 | if (ret) | |
a8259075 SR |
5843 | return ret; |
5844 | ||
f2d84b65 | 5845 | if (val != 0 && val != 1) |
a8259075 | 5846 | return -EINVAL; |
69d34da2 SRRH |
5847 | |
5848 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 5849 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 5850 | mutex_unlock(&trace_types_lock); |
a8259075 | 5851 | |
613f04a0 SRRH |
5852 | if (ret < 0) |
5853 | return ret; | |
5854 | ||
a8259075 SR |
5855 | *ppos += cnt; |
5856 | ||
5857 | return cnt; | |
5858 | } | |
5859 | ||
a8259075 SR |
5860 | static const struct file_operations trace_options_core_fops = { |
5861 | .open = tracing_open_generic, | |
5862 | .read = trace_options_core_read, | |
5863 | .write = trace_options_core_write, | |
b444786f | 5864 | .llseek = generic_file_llseek, |
a8259075 SR |
5865 | }; |
5866 | ||
5452af66 | 5867 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 5868 | umode_t mode, |
5452af66 FW |
5869 | struct dentry *parent, |
5870 | void *data, | |
5871 | const struct file_operations *fops) | |
5872 | { | |
5873 | struct dentry *ret; | |
5874 | ||
5875 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
5876 | if (!ret) | |
5877 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
5878 | ||
5879 | return ret; | |
5880 | } | |
5881 | ||
5882 | ||
2b6080f2 | 5883 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
5884 | { |
5885 | struct dentry *d_tracer; | |
a8259075 | 5886 | |
2b6080f2 SR |
5887 | if (tr->options) |
5888 | return tr->options; | |
a8259075 | 5889 | |
2b6080f2 | 5890 | d_tracer = tracing_init_dentry_tr(tr); |
a8259075 SR |
5891 | if (!d_tracer) |
5892 | return NULL; | |
5893 | ||
2b6080f2 SR |
5894 | tr->options = debugfs_create_dir("options", d_tracer); |
5895 | if (!tr->options) { | |
a8259075 SR |
5896 | pr_warning("Could not create debugfs directory 'options'\n"); |
5897 | return NULL; | |
5898 | } | |
5899 | ||
2b6080f2 | 5900 | return tr->options; |
a8259075 SR |
5901 | } |
5902 | ||
577b785f | 5903 | static void |
2b6080f2 SR |
5904 | create_trace_option_file(struct trace_array *tr, |
5905 | struct trace_option_dentry *topt, | |
577b785f SR |
5906 | struct tracer_flags *flags, |
5907 | struct tracer_opt *opt) | |
5908 | { | |
5909 | struct dentry *t_options; | |
577b785f | 5910 | |
2b6080f2 | 5911 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
5912 | if (!t_options) |
5913 | return; | |
5914 | ||
5915 | topt->flags = flags; | |
5916 | topt->opt = opt; | |
2b6080f2 | 5917 | topt->tr = tr; |
577b785f | 5918 | |
5452af66 | 5919 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
5920 | &trace_options_fops); |
5921 | ||
577b785f SR |
5922 | } |
5923 | ||
5924 | static struct trace_option_dentry * | |
2b6080f2 | 5925 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
5926 | { |
5927 | struct trace_option_dentry *topts; | |
5928 | struct tracer_flags *flags; | |
5929 | struct tracer_opt *opts; | |
5930 | int cnt; | |
5931 | ||
5932 | if (!tracer) | |
5933 | return NULL; | |
5934 | ||
5935 | flags = tracer->flags; | |
5936 | ||
5937 | if (!flags || !flags->opts) | |
5938 | return NULL; | |
5939 | ||
5940 | opts = flags->opts; | |
5941 | ||
5942 | for (cnt = 0; opts[cnt].name; cnt++) | |
5943 | ; | |
5944 | ||
0cfe8245 | 5945 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
5946 | if (!topts) |
5947 | return NULL; | |
5948 | ||
5949 | for (cnt = 0; opts[cnt].name; cnt++) | |
2b6080f2 | 5950 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f SR |
5951 | &opts[cnt]); |
5952 | ||
5953 | return topts; | |
5954 | } | |
5955 | ||
5956 | static void | |
5957 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
5958 | { | |
5959 | int cnt; | |
5960 | ||
5961 | if (!topts) | |
5962 | return; | |
5963 | ||
5964 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
5965 | if (topts[cnt].entry) | |
5966 | debugfs_remove(topts[cnt].entry); | |
5967 | } | |
5968 | ||
5969 | kfree(topts); | |
5970 | } | |
5971 | ||
a8259075 | 5972 | static struct dentry * |
2b6080f2 SR |
5973 | create_trace_option_core_file(struct trace_array *tr, |
5974 | const char *option, long index) | |
a8259075 SR |
5975 | { |
5976 | struct dentry *t_options; | |
a8259075 | 5977 | |
2b6080f2 | 5978 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5979 | if (!t_options) |
5980 | return NULL; | |
5981 | ||
5452af66 | 5982 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 5983 | &trace_options_core_fops); |
a8259075 SR |
5984 | } |
5985 | ||
2b6080f2 | 5986 | static __init void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
5987 | { |
5988 | struct dentry *t_options; | |
a8259075 SR |
5989 | int i; |
5990 | ||
2b6080f2 | 5991 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
5992 | if (!t_options) |
5993 | return; | |
5994 | ||
5452af66 | 5995 | for (i = 0; trace_options[i]; i++) |
2b6080f2 | 5996 | create_trace_option_core_file(tr, trace_options[i], i); |
a8259075 SR |
5997 | } |
5998 | ||
499e5470 SR |
5999 | static ssize_t |
6000 | rb_simple_read(struct file *filp, char __user *ubuf, | |
6001 | size_t cnt, loff_t *ppos) | |
6002 | { | |
348f0fc2 | 6003 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
6004 | char buf[64]; |
6005 | int r; | |
6006 | ||
10246fa3 | 6007 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
6008 | r = sprintf(buf, "%d\n", r); |
6009 | ||
6010 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
6011 | } | |
6012 | ||
6013 | static ssize_t | |
6014 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
6015 | size_t cnt, loff_t *ppos) | |
6016 | { | |
348f0fc2 | 6017 | struct trace_array *tr = filp->private_data; |
12883efb | 6018 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
6019 | unsigned long val; |
6020 | int ret; | |
6021 | ||
6022 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
6023 | if (ret) | |
6024 | return ret; | |
6025 | ||
6026 | if (buffer) { | |
2df8f8a6 SR |
6027 | mutex_lock(&trace_types_lock); |
6028 | if (val) { | |
10246fa3 | 6029 | tracer_tracing_on(tr); |
2b6080f2 SR |
6030 | if (tr->current_trace->start) |
6031 | tr->current_trace->start(tr); | |
2df8f8a6 | 6032 | } else { |
10246fa3 | 6033 | tracer_tracing_off(tr); |
2b6080f2 SR |
6034 | if (tr->current_trace->stop) |
6035 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
6036 | } |
6037 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
6038 | } |
6039 | ||
6040 | (*ppos)++; | |
6041 | ||
6042 | return cnt; | |
6043 | } | |
6044 | ||
6045 | static const struct file_operations rb_simple_fops = { | |
7b85af63 | 6046 | .open = tracing_open_generic_tr, |
499e5470 SR |
6047 | .read = rb_simple_read, |
6048 | .write = rb_simple_write, | |
7b85af63 | 6049 | .release = tracing_release_generic_tr, |
499e5470 SR |
6050 | .llseek = default_llseek, |
6051 | }; | |
6052 | ||
277ba044 SR |
6053 | struct dentry *trace_instance_dir; |
6054 | ||
6055 | static void | |
6056 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer); | |
6057 | ||
55034cd6 SRRH |
6058 | static int |
6059 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
6060 | { |
6061 | enum ring_buffer_flags rb_flags; | |
737223fb SRRH |
6062 | |
6063 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; | |
6064 | ||
dced341b SRRH |
6065 | buf->tr = tr; |
6066 | ||
55034cd6 SRRH |
6067 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
6068 | if (!buf->buffer) | |
6069 | return -ENOMEM; | |
737223fb | 6070 | |
55034cd6 SRRH |
6071 | buf->data = alloc_percpu(struct trace_array_cpu); |
6072 | if (!buf->data) { | |
6073 | ring_buffer_free(buf->buffer); | |
6074 | return -ENOMEM; | |
6075 | } | |
737223fb | 6076 | |
737223fb SRRH |
6077 | /* Allocate the first page for all buffers */ |
6078 | set_buffer_entries(&tr->trace_buffer, | |
6079 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
6080 | ||
55034cd6 SRRH |
6081 | return 0; |
6082 | } | |
737223fb | 6083 | |
55034cd6 SRRH |
6084 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
6085 | { | |
6086 | int ret; | |
737223fb | 6087 | |
55034cd6 SRRH |
6088 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
6089 | if (ret) | |
6090 | return ret; | |
737223fb | 6091 | |
55034cd6 SRRH |
6092 | #ifdef CONFIG_TRACER_MAX_TRACE |
6093 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
6094 | allocate_snapshot ? size : 1); | |
6095 | if (WARN_ON(ret)) { | |
737223fb | 6096 | ring_buffer_free(tr->trace_buffer.buffer); |
55034cd6 SRRH |
6097 | free_percpu(tr->trace_buffer.data); |
6098 | return -ENOMEM; | |
6099 | } | |
6100 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 6101 | |
55034cd6 SRRH |
6102 | /* |
6103 | * Only the top level trace array gets its snapshot allocated | |
6104 | * from the kernel command line. | |
6105 | */ | |
6106 | allocate_snapshot = false; | |
737223fb | 6107 | #endif |
55034cd6 | 6108 | return 0; |
737223fb SRRH |
6109 | } |
6110 | ||
6111 | static int new_instance_create(const char *name) | |
6112 | { | |
277ba044 SR |
6113 | struct trace_array *tr; |
6114 | int ret; | |
277ba044 SR |
6115 | |
6116 | mutex_lock(&trace_types_lock); | |
6117 | ||
6118 | ret = -EEXIST; | |
6119 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6120 | if (tr->name && strcmp(tr->name, name) == 0) | |
6121 | goto out_unlock; | |
6122 | } | |
6123 | ||
6124 | ret = -ENOMEM; | |
6125 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
6126 | if (!tr) | |
6127 | goto out_unlock; | |
6128 | ||
6129 | tr->name = kstrdup(name, GFP_KERNEL); | |
6130 | if (!tr->name) | |
6131 | goto out_free_tr; | |
6132 | ||
ccfe9e42 AL |
6133 | if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) |
6134 | goto out_free_tr; | |
6135 | ||
6136 | cpumask_copy(tr->tracing_cpumask, cpu_all_mask); | |
6137 | ||
277ba044 SR |
6138 | raw_spin_lock_init(&tr->start_lock); |
6139 | ||
0b9b12c1 SRRH |
6140 | tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
6141 | ||
277ba044 SR |
6142 | tr->current_trace = &nop_trace; |
6143 | ||
6144 | INIT_LIST_HEAD(&tr->systems); | |
6145 | INIT_LIST_HEAD(&tr->events); | |
6146 | ||
737223fb | 6147 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
6148 | goto out_free_tr; |
6149 | ||
277ba044 SR |
6150 | tr->dir = debugfs_create_dir(name, trace_instance_dir); |
6151 | if (!tr->dir) | |
6152 | goto out_free_tr; | |
6153 | ||
6154 | ret = event_trace_add_tracer(tr->dir, tr); | |
609e85a7 AL |
6155 | if (ret) { |
6156 | debugfs_remove_recursive(tr->dir); | |
277ba044 | 6157 | goto out_free_tr; |
609e85a7 | 6158 | } |
277ba044 SR |
6159 | |
6160 | init_tracer_debugfs(tr, tr->dir); | |
6161 | ||
6162 | list_add(&tr->list, &ftrace_trace_arrays); | |
6163 | ||
6164 | mutex_unlock(&trace_types_lock); | |
6165 | ||
6166 | return 0; | |
6167 | ||
6168 | out_free_tr: | |
12883efb SRRH |
6169 | if (tr->trace_buffer.buffer) |
6170 | ring_buffer_free(tr->trace_buffer.buffer); | |
ccfe9e42 | 6171 | free_cpumask_var(tr->tracing_cpumask); |
277ba044 SR |
6172 | kfree(tr->name); |
6173 | kfree(tr); | |
6174 | ||
6175 | out_unlock: | |
6176 | mutex_unlock(&trace_types_lock); | |
6177 | ||
6178 | return ret; | |
6179 | ||
6180 | } | |
6181 | ||
0c8916c3 SR |
6182 | static int instance_delete(const char *name) |
6183 | { | |
6184 | struct trace_array *tr; | |
6185 | int found = 0; | |
6186 | int ret; | |
6187 | ||
6188 | mutex_lock(&trace_types_lock); | |
6189 | ||
6190 | ret = -ENODEV; | |
6191 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6192 | if (tr->name && strcmp(tr->name, name) == 0) { | |
6193 | found = 1; | |
6194 | break; | |
6195 | } | |
6196 | } | |
6197 | if (!found) | |
6198 | goto out_unlock; | |
6199 | ||
a695cb58 SRRH |
6200 | ret = -EBUSY; |
6201 | if (tr->ref) | |
6202 | goto out_unlock; | |
6203 | ||
0c8916c3 SR |
6204 | list_del(&tr->list); |
6205 | ||
6b450d25 | 6206 | tracing_set_nop(tr); |
0c8916c3 | 6207 | event_trace_del_tracer(tr); |
591dffda | 6208 | ftrace_destroy_function_files(tr); |
0c8916c3 | 6209 | debugfs_remove_recursive(tr->dir); |
12883efb SRRH |
6210 | free_percpu(tr->trace_buffer.data); |
6211 | ring_buffer_free(tr->trace_buffer.buffer); | |
0c8916c3 SR |
6212 | |
6213 | kfree(tr->name); | |
6214 | kfree(tr); | |
6215 | ||
6216 | ret = 0; | |
6217 | ||
6218 | out_unlock: | |
6219 | mutex_unlock(&trace_types_lock); | |
6220 | ||
6221 | return ret; | |
6222 | } | |
6223 | ||
277ba044 SR |
6224 | static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t mode) |
6225 | { | |
6226 | struct dentry *parent; | |
6227 | int ret; | |
6228 | ||
6229 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
6230 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
6231 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
6232 | return -ENOENT; | |
6233 | ||
6234 | /* | |
6235 | * The inode mutex is locked, but debugfs_create_dir() will also | |
6236 | * take the mutex. As the instances directory can not be destroyed | |
6237 | * or changed in any other way, it is safe to unlock it, and | |
6238 | * let the dentry try. If two users try to make the same dir at | |
6239 | * the same time, then the new_instance_create() will determine the | |
6240 | * winner. | |
6241 | */ | |
6242 | mutex_unlock(&inode->i_mutex); | |
6243 | ||
6244 | ret = new_instance_create(dentry->d_iname); | |
6245 | ||
6246 | mutex_lock(&inode->i_mutex); | |
6247 | ||
6248 | return ret; | |
6249 | } | |
6250 | ||
0c8916c3 SR |
6251 | static int instance_rmdir(struct inode *inode, struct dentry *dentry) |
6252 | { | |
6253 | struct dentry *parent; | |
6254 | int ret; | |
6255 | ||
6256 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
6257 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_alias); | |
6258 | if (WARN_ON_ONCE(parent != trace_instance_dir)) | |
6259 | return -ENOENT; | |
6260 | ||
6261 | /* The caller did a dget() on dentry */ | |
6262 | mutex_unlock(&dentry->d_inode->i_mutex); | |
6263 | ||
6264 | /* | |
6265 | * The inode mutex is locked, but debugfs_create_dir() will also | |
6266 | * take the mutex. As the instances directory can not be destroyed | |
6267 | * or changed in any other way, it is safe to unlock it, and | |
6268 | * let the dentry try. If two users try to make the same dir at | |
6269 | * the same time, then the instance_delete() will determine the | |
6270 | * winner. | |
6271 | */ | |
6272 | mutex_unlock(&inode->i_mutex); | |
6273 | ||
6274 | ret = instance_delete(dentry->d_iname); | |
6275 | ||
6276 | mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); | |
6277 | mutex_lock(&dentry->d_inode->i_mutex); | |
6278 | ||
6279 | return ret; | |
6280 | } | |
6281 | ||
277ba044 SR |
6282 | static const struct inode_operations instance_dir_inode_operations = { |
6283 | .lookup = simple_lookup, | |
6284 | .mkdir = instance_mkdir, | |
0c8916c3 | 6285 | .rmdir = instance_rmdir, |
277ba044 SR |
6286 | }; |
6287 | ||
6288 | static __init void create_trace_instances(struct dentry *d_tracer) | |
6289 | { | |
6290 | trace_instance_dir = debugfs_create_dir("instances", d_tracer); | |
6291 | if (WARN_ON(!trace_instance_dir)) | |
6292 | return; | |
6293 | ||
6294 | /* Hijack the dir inode operations, to allow mkdir */ | |
6295 | trace_instance_dir->d_inode->i_op = &instance_dir_inode_operations; | |
6296 | } | |
6297 | ||
2b6080f2 SR |
6298 | static void |
6299 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) | |
6300 | { | |
121aaee7 | 6301 | int cpu; |
2b6080f2 | 6302 | |
607e2ea1 SRRH |
6303 | trace_create_file("available_tracers", 0444, d_tracer, |
6304 | tr, &show_traces_fops); | |
6305 | ||
6306 | trace_create_file("current_tracer", 0644, d_tracer, | |
6307 | tr, &set_tracer_fops); | |
6308 | ||
ccfe9e42 AL |
6309 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
6310 | tr, &tracing_cpumask_fops); | |
6311 | ||
2b6080f2 SR |
6312 | trace_create_file("trace_options", 0644, d_tracer, |
6313 | tr, &tracing_iter_fops); | |
6314 | ||
6315 | trace_create_file("trace", 0644, d_tracer, | |
6484c71c | 6316 | tr, &tracing_fops); |
2b6080f2 SR |
6317 | |
6318 | trace_create_file("trace_pipe", 0444, d_tracer, | |
15544209 | 6319 | tr, &tracing_pipe_fops); |
2b6080f2 SR |
6320 | |
6321 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
0bc392ee | 6322 | tr, &tracing_entries_fops); |
2b6080f2 SR |
6323 | |
6324 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
6325 | tr, &tracing_total_entries_fops); | |
6326 | ||
238ae93d | 6327 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
6328 | tr, &tracing_free_buffer_fops); |
6329 | ||
6330 | trace_create_file("trace_marker", 0220, d_tracer, | |
6331 | tr, &tracing_mark_fops); | |
6332 | ||
6333 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
6334 | &trace_clock_fops); | |
6335 | ||
6336 | trace_create_file("tracing_on", 0644, d_tracer, | |
6484c71c | 6337 | tr, &rb_simple_fops); |
ce9bae55 | 6338 | |
6d9b3fa5 SRRH |
6339 | #ifdef CONFIG_TRACER_MAX_TRACE |
6340 | trace_create_file("tracing_max_latency", 0644, d_tracer, | |
6341 | &tr->max_latency, &tracing_max_lat_fops); | |
6342 | #endif | |
6343 | ||
591dffda SRRH |
6344 | if (ftrace_create_function_files(tr, d_tracer)) |
6345 | WARN(1, "Could not allocate function filter files"); | |
6346 | ||
ce9bae55 SRRH |
6347 | #ifdef CONFIG_TRACER_SNAPSHOT |
6348 | trace_create_file("snapshot", 0644, d_tracer, | |
6484c71c | 6349 | tr, &snapshot_fops); |
ce9bae55 | 6350 | #endif |
121aaee7 SRRH |
6351 | |
6352 | for_each_tracing_cpu(cpu) | |
6353 | tracing_init_debugfs_percpu(tr, cpu); | |
6354 | ||
2b6080f2 SR |
6355 | } |
6356 | ||
b5ad384e | 6357 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
6358 | { |
6359 | struct dentry *d_tracer; | |
bc0c38d1 | 6360 | |
7e53bd42 LJ |
6361 | trace_access_lock_init(); |
6362 | ||
bc0c38d1 | 6363 | d_tracer = tracing_init_dentry(); |
ed6f1c99 NK |
6364 | if (!d_tracer) |
6365 | return 0; | |
bc0c38d1 | 6366 | |
2b6080f2 | 6367 | init_tracer_debugfs(&global_trace, d_tracer); |
bc0c38d1 | 6368 | |
5452af66 FW |
6369 | trace_create_file("tracing_thresh", 0644, d_tracer, |
6370 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 6371 | |
339ae5d3 | 6372 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
6373 | NULL, &tracing_readme_fops); |
6374 | ||
69abe6a5 AP |
6375 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
6376 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 6377 | |
bc0c38d1 | 6378 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
6379 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
6380 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 6381 | #endif |
b04cc6b1 | 6382 | |
277ba044 | 6383 | create_trace_instances(d_tracer); |
5452af66 | 6384 | |
2b6080f2 | 6385 | create_trace_options_dir(&global_trace); |
b04cc6b1 | 6386 | |
b5ad384e | 6387 | return 0; |
bc0c38d1 SR |
6388 | } |
6389 | ||
3f5a54e3 SR |
6390 | static int trace_panic_handler(struct notifier_block *this, |
6391 | unsigned long event, void *unused) | |
6392 | { | |
944ac425 | 6393 | if (ftrace_dump_on_oops) |
cecbca96 | 6394 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6395 | return NOTIFY_OK; |
6396 | } | |
6397 | ||
6398 | static struct notifier_block trace_panic_notifier = { | |
6399 | .notifier_call = trace_panic_handler, | |
6400 | .next = NULL, | |
6401 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
6402 | }; | |
6403 | ||
6404 | static int trace_die_handler(struct notifier_block *self, | |
6405 | unsigned long val, | |
6406 | void *data) | |
6407 | { | |
6408 | switch (val) { | |
6409 | case DIE_OOPS: | |
944ac425 | 6410 | if (ftrace_dump_on_oops) |
cecbca96 | 6411 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6412 | break; |
6413 | default: | |
6414 | break; | |
6415 | } | |
6416 | return NOTIFY_OK; | |
6417 | } | |
6418 | ||
6419 | static struct notifier_block trace_die_notifier = { | |
6420 | .notifier_call = trace_die_handler, | |
6421 | .priority = 200 | |
6422 | }; | |
6423 | ||
6424 | /* | |
6425 | * printk is set to max of 1024, we really don't need it that big. | |
6426 | * Nothing should be printing 1000 characters anyway. | |
6427 | */ | |
6428 | #define TRACE_MAX_PRINT 1000 | |
6429 | ||
6430 | /* | |
6431 | * Define here KERN_TRACE so that we have one place to modify | |
6432 | * it if we decide to change what log level the ftrace dump | |
6433 | * should be at. | |
6434 | */ | |
428aee14 | 6435 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 6436 | |
955b61e5 | 6437 | void |
3f5a54e3 SR |
6438 | trace_printk_seq(struct trace_seq *s) |
6439 | { | |
6440 | /* Probably should print a warning here. */ | |
bd6df187 J |
6441 | if (s->len >= TRACE_MAX_PRINT) |
6442 | s->len = TRACE_MAX_PRINT; | |
3f5a54e3 SR |
6443 | |
6444 | /* should be zero ended, but we are paranoid. */ | |
6445 | s->buffer[s->len] = 0; | |
6446 | ||
6447 | printk(KERN_TRACE "%s", s->buffer); | |
6448 | ||
f9520750 | 6449 | trace_seq_init(s); |
3f5a54e3 SR |
6450 | } |
6451 | ||
955b61e5 JW |
6452 | void trace_init_global_iter(struct trace_iterator *iter) |
6453 | { | |
6454 | iter->tr = &global_trace; | |
2b6080f2 | 6455 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 6456 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 6457 | iter->trace_buffer = &global_trace.trace_buffer; |
b2f974d6 CS |
6458 | |
6459 | if (iter->trace && iter->trace->open) | |
6460 | iter->trace->open(iter); | |
6461 | ||
6462 | /* Annotate start of buffers if we had overruns */ | |
6463 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) | |
6464 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
6465 | ||
6466 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ | |
6467 | if (trace_clocks[iter->tr->clock_id].in_ns) | |
6468 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
955b61e5 JW |
6469 | } |
6470 | ||
7fe70b57 | 6471 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 6472 | { |
3f5a54e3 SR |
6473 | /* use static because iter can be a bit big for the stack */ |
6474 | static struct trace_iterator iter; | |
7fe70b57 | 6475 | static atomic_t dump_running; |
cf586b61 | 6476 | unsigned int old_userobj; |
d769041f SR |
6477 | unsigned long flags; |
6478 | int cnt = 0, cpu; | |
3f5a54e3 | 6479 | |
7fe70b57 SRRH |
6480 | /* Only allow one dump user at a time. */ |
6481 | if (atomic_inc_return(&dump_running) != 1) { | |
6482 | atomic_dec(&dump_running); | |
6483 | return; | |
6484 | } | |
3f5a54e3 | 6485 | |
7fe70b57 SRRH |
6486 | /* |
6487 | * Always turn off tracing when we dump. | |
6488 | * We don't need to show trace output of what happens | |
6489 | * between multiple crashes. | |
6490 | * | |
6491 | * If the user does a sysrq-z, then they can re-enable | |
6492 | * tracing with echo 1 > tracing_on. | |
6493 | */ | |
0ee6b6cf | 6494 | tracing_off(); |
cf586b61 | 6495 | |
7fe70b57 | 6496 | local_irq_save(flags); |
3f5a54e3 | 6497 | |
38dbe0b1 | 6498 | /* Simulate the iterator */ |
955b61e5 JW |
6499 | trace_init_global_iter(&iter); |
6500 | ||
d769041f | 6501 | for_each_tracing_cpu(cpu) { |
12883efb | 6502 | atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled); |
d769041f SR |
6503 | } |
6504 | ||
cf586b61 FW |
6505 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
6506 | ||
b54d3de9 TE |
6507 | /* don't look at user memory in panic mode */ |
6508 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
6509 | ||
cecbca96 FW |
6510 | switch (oops_dump_mode) { |
6511 | case DUMP_ALL: | |
ae3b5093 | 6512 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6513 | break; |
6514 | case DUMP_ORIG: | |
6515 | iter.cpu_file = raw_smp_processor_id(); | |
6516 | break; | |
6517 | case DUMP_NONE: | |
6518 | goto out_enable; | |
6519 | default: | |
6520 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 6521 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6522 | } |
6523 | ||
6524 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 6525 | |
7fe70b57 SRRH |
6526 | /* Did function tracer already get disabled? */ |
6527 | if (ftrace_is_dead()) { | |
6528 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
6529 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
6530 | } | |
6531 | ||
3f5a54e3 SR |
6532 | /* |
6533 | * We need to stop all tracing on all CPUS to read the | |
6534 | * the next buffer. This is a bit expensive, but is | |
6535 | * not done often. We fill all what we can read, | |
6536 | * and then release the locks again. | |
6537 | */ | |
6538 | ||
3f5a54e3 SR |
6539 | while (!trace_empty(&iter)) { |
6540 | ||
6541 | if (!cnt) | |
6542 | printk(KERN_TRACE "---------------------------------\n"); | |
6543 | ||
6544 | cnt++; | |
6545 | ||
6546 | /* reset all but tr, trace, and overruns */ | |
6547 | memset(&iter.seq, 0, | |
6548 | sizeof(struct trace_iterator) - | |
6549 | offsetof(struct trace_iterator, seq)); | |
6550 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
6551 | iter.pos = -1; | |
6552 | ||
955b61e5 | 6553 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
6554 | int ret; |
6555 | ||
6556 | ret = print_trace_line(&iter); | |
6557 | if (ret != TRACE_TYPE_NO_CONSUME) | |
6558 | trace_consume(&iter); | |
3f5a54e3 | 6559 | } |
b892e5c8 | 6560 | touch_nmi_watchdog(); |
3f5a54e3 SR |
6561 | |
6562 | trace_printk_seq(&iter.seq); | |
6563 | } | |
6564 | ||
6565 | if (!cnt) | |
6566 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
6567 | else | |
6568 | printk(KERN_TRACE "---------------------------------\n"); | |
6569 | ||
cecbca96 | 6570 | out_enable: |
7fe70b57 | 6571 | trace_flags |= old_userobj; |
cf586b61 | 6572 | |
7fe70b57 SRRH |
6573 | for_each_tracing_cpu(cpu) { |
6574 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); | |
cf586b61 | 6575 | } |
7fe70b57 | 6576 | atomic_dec(&dump_running); |
cd891ae0 | 6577 | local_irq_restore(flags); |
3f5a54e3 | 6578 | } |
a8eecf22 | 6579 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 6580 | |
3928a8a2 | 6581 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 6582 | { |
73c5162a | 6583 | int ring_buf_size; |
9e01c1b7 | 6584 | int ret = -ENOMEM; |
4c11d7ae | 6585 | |
750912fa | 6586 | |
9e01c1b7 RR |
6587 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
6588 | goto out; | |
6589 | ||
ccfe9e42 | 6590 | if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) |
9e01c1b7 | 6591 | goto out_free_buffer_mask; |
4c11d7ae | 6592 | |
07d777fe SR |
6593 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
6594 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 6595 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
6596 | trace_printk_init_buffers(); |
6597 | ||
73c5162a SR |
6598 | /* To save memory, keep the ring buffer size to its minimum */ |
6599 | if (ring_buffer_expanded) | |
6600 | ring_buf_size = trace_buf_size; | |
6601 | else | |
6602 | ring_buf_size = 1; | |
6603 | ||
9e01c1b7 | 6604 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
ccfe9e42 | 6605 | cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); |
9e01c1b7 | 6606 | |
2b6080f2 SR |
6607 | raw_spin_lock_init(&global_trace.start_lock); |
6608 | ||
2c4a33ab SRRH |
6609 | /* Used for event triggers */ |
6610 | temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); | |
6611 | if (!temp_buffer) | |
6612 | goto out_free_cpumask; | |
6613 | ||
9e01c1b7 | 6614 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 6615 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
6616 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
6617 | WARN_ON(1); | |
2c4a33ab | 6618 | goto out_free_temp_buffer; |
4c11d7ae | 6619 | } |
a7603ff4 | 6620 | |
499e5470 SR |
6621 | if (global_trace.buffer_disabled) |
6622 | tracing_off(); | |
4c11d7ae | 6623 | |
bc0c38d1 SR |
6624 | trace_init_cmdlines(); |
6625 | ||
e1e232ca SR |
6626 | if (trace_boot_clock) { |
6627 | ret = tracing_set_clock(&global_trace, trace_boot_clock); | |
6628 | if (ret < 0) | |
6629 | pr_warning("Trace clock %s not defined, going back to default\n", | |
6630 | trace_boot_clock); | |
6631 | } | |
6632 | ||
ca164318 SRRH |
6633 | /* |
6634 | * register_tracer() might reference current_trace, so it | |
6635 | * needs to be set before we register anything. This is | |
6636 | * just a bootstrap of current_trace anyway. | |
6637 | */ | |
2b6080f2 SR |
6638 | global_trace.current_trace = &nop_trace; |
6639 | ||
0b9b12c1 SRRH |
6640 | global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
6641 | ||
4104d326 SRRH |
6642 | ftrace_init_global_array_ops(&global_trace); |
6643 | ||
ca164318 SRRH |
6644 | register_tracer(&nop_trace); |
6645 | ||
60a11774 SR |
6646 | /* All seems OK, enable tracing */ |
6647 | tracing_disabled = 0; | |
3928a8a2 | 6648 | |
3f5a54e3 SR |
6649 | atomic_notifier_chain_register(&panic_notifier_list, |
6650 | &trace_panic_notifier); | |
6651 | ||
6652 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 6653 | |
ae63b31e SR |
6654 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
6655 | ||
6656 | INIT_LIST_HEAD(&global_trace.systems); | |
6657 | INIT_LIST_HEAD(&global_trace.events); | |
6658 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
6659 | ||
7bcfaf54 SR |
6660 | while (trace_boot_options) { |
6661 | char *option; | |
6662 | ||
6663 | option = strsep(&trace_boot_options, ","); | |
2b6080f2 | 6664 | trace_set_options(&global_trace, option); |
7bcfaf54 SR |
6665 | } |
6666 | ||
77fd5c15 SRRH |
6667 | register_snapshot_cmd(); |
6668 | ||
2fc1dfbe | 6669 | return 0; |
3f5a54e3 | 6670 | |
2c4a33ab SRRH |
6671 | out_free_temp_buffer: |
6672 | ring_buffer_free(temp_buffer); | |
9e01c1b7 | 6673 | out_free_cpumask: |
ccfe9e42 | 6674 | free_cpumask_var(global_trace.tracing_cpumask); |
9e01c1b7 RR |
6675 | out_free_buffer_mask: |
6676 | free_cpumask_var(tracing_buffer_mask); | |
6677 | out: | |
6678 | return ret; | |
bc0c38d1 | 6679 | } |
b2821ae6 SR |
6680 | |
6681 | __init static int clear_boot_tracer(void) | |
6682 | { | |
6683 | /* | |
6684 | * The default tracer at boot buffer is an init section. | |
6685 | * This function is called in lateinit. If we did not | |
6686 | * find the boot tracer, then clear it out, to prevent | |
6687 | * later registration from accessing the buffer that is | |
6688 | * about to be freed. | |
6689 | */ | |
6690 | if (!default_bootup_tracer) | |
6691 | return 0; | |
6692 | ||
6693 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
6694 | default_bootup_tracer); | |
6695 | default_bootup_tracer = NULL; | |
6696 | ||
6697 | return 0; | |
6698 | } | |
6699 | ||
b5ad384e FW |
6700 | early_initcall(tracer_alloc_buffers); |
6701 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 6702 | late_initcall(clear_boot_tracer); |