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 | |
0daa2302 SRRH |
66 | /* Pipe tracepoints to printk */ |
67 | struct trace_iterator *tracepoint_print_iter; | |
68 | int tracepoint_printk; | |
69 | ||
adf9f195 FW |
70 | /* For tracers that don't implement custom flags */ |
71 | static struct tracer_opt dummy_tracer_opt[] = { | |
72 | { } | |
73 | }; | |
74 | ||
75 | static struct tracer_flags dummy_tracer_flags = { | |
76 | .val = 0, | |
77 | .opts = dummy_tracer_opt | |
78 | }; | |
79 | ||
8c1a49ae SRRH |
80 | static int |
81 | dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) | |
adf9f195 FW |
82 | { |
83 | return 0; | |
84 | } | |
0f048701 | 85 | |
7ffbd48d SR |
86 | /* |
87 | * To prevent the comm cache from being overwritten when no | |
88 | * tracing is active, only save the comm when a trace event | |
89 | * occurred. | |
90 | */ | |
91 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
92 | ||
0f048701 SR |
93 | /* |
94 | * Kill all tracing for good (never come back). | |
95 | * It is initialized to 1 but will turn to zero if the initialization | |
96 | * of the tracer is successful. But that is the only place that sets | |
97 | * this back to zero. | |
98 | */ | |
4fd27358 | 99 | static int tracing_disabled = 1; |
0f048701 | 100 | |
9288f99a | 101 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 102 | |
955b61e5 | 103 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 104 | |
944ac425 SR |
105 | /* |
106 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
107 | * | |
108 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
109 | * is set, then ftrace_dump is called. This will output the contents | |
110 | * of the ftrace buffers to the console. This is very useful for | |
111 | * capturing traces that lead to crashes and outputing it to a | |
112 | * serial console. | |
113 | * | |
114 | * It is default off, but you can enable it with either specifying | |
115 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
116 | * /proc/sys/kernel/ftrace_dump_on_oops |
117 | * Set 1 if you want to dump buffers of all CPUs | |
118 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 119 | */ |
cecbca96 FW |
120 | |
121 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 122 | |
de7edd31 SRRH |
123 | /* When set, tracing will stop when a WARN*() is hit */ |
124 | int __disable_trace_on_warning; | |
125 | ||
607e2ea1 | 126 | static int tracing_set_tracer(struct trace_array *tr, const char *buf); |
b2821ae6 | 127 | |
ee6c2c1b LZ |
128 | #define MAX_TRACER_SIZE 100 |
129 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 130 | static char *default_bootup_tracer; |
d9e54076 | 131 | |
55034cd6 SRRH |
132 | static bool allocate_snapshot; |
133 | ||
1beee96b | 134 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 135 | { |
67012ab1 | 136 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 137 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 138 | /* We are using ftrace early, expand it */ |
55034cd6 | 139 | ring_buffer_expanded = true; |
d9e54076 PZ |
140 | return 1; |
141 | } | |
1beee96b | 142 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 143 | |
944ac425 SR |
144 | static int __init set_ftrace_dump_on_oops(char *str) |
145 | { | |
cecbca96 FW |
146 | if (*str++ != '=' || !*str) { |
147 | ftrace_dump_on_oops = DUMP_ALL; | |
148 | return 1; | |
149 | } | |
150 | ||
151 | if (!strcmp("orig_cpu", str)) { | |
152 | ftrace_dump_on_oops = DUMP_ORIG; | |
153 | return 1; | |
154 | } | |
155 | ||
156 | return 0; | |
944ac425 SR |
157 | } |
158 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 159 | |
de7edd31 SRRH |
160 | static int __init stop_trace_on_warning(char *str) |
161 | { | |
933ff9f2 LCG |
162 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) |
163 | __disable_trace_on_warning = 1; | |
de7edd31 SRRH |
164 | return 1; |
165 | } | |
933ff9f2 | 166 | __setup("traceoff_on_warning", stop_trace_on_warning); |
de7edd31 | 167 | |
3209cff4 | 168 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
169 | { |
170 | allocate_snapshot = true; | |
171 | /* We also need the main ring buffer expanded */ | |
172 | ring_buffer_expanded = true; | |
173 | return 1; | |
174 | } | |
3209cff4 | 175 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 176 | |
7bcfaf54 SR |
177 | |
178 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
179 | static char *trace_boot_options __initdata; | |
180 | ||
181 | static int __init set_trace_boot_options(char *str) | |
182 | { | |
67012ab1 | 183 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
184 | trace_boot_options = trace_boot_options_buf; |
185 | return 0; | |
186 | } | |
187 | __setup("trace_options=", set_trace_boot_options); | |
188 | ||
e1e232ca SR |
189 | static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; |
190 | static char *trace_boot_clock __initdata; | |
191 | ||
192 | static int __init set_trace_boot_clock(char *str) | |
193 | { | |
194 | strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); | |
195 | trace_boot_clock = trace_boot_clock_buf; | |
196 | return 0; | |
197 | } | |
198 | __setup("trace_clock=", set_trace_boot_clock); | |
199 | ||
0daa2302 SRRH |
200 | static int __init set_tracepoint_printk(char *str) |
201 | { | |
202 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) | |
203 | tracepoint_printk = 1; | |
204 | return 1; | |
205 | } | |
206 | __setup("tp_printk", set_tracepoint_printk); | |
de7edd31 | 207 | |
cf8e3474 | 208 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
209 | { |
210 | nsec += 500; | |
211 | do_div(nsec, 1000); | |
212 | return nsec; | |
213 | } | |
214 | ||
4fcdae83 SR |
215 | /* |
216 | * The global_trace is the descriptor that holds the tracing | |
217 | * buffers for the live tracing. For each CPU, it contains | |
218 | * a link list of pages that will store trace entries. The | |
219 | * page descriptor of the pages in the memory is used to hold | |
220 | * the link list by linking the lru item in the page descriptor | |
221 | * to each of the pages in the buffer per CPU. | |
222 | * | |
223 | * For each active CPU there is a data field that holds the | |
224 | * pages for the buffer for that CPU. Each CPU has the same number | |
225 | * of pages allocated for its buffer. | |
226 | */ | |
bc0c38d1 SR |
227 | static struct trace_array global_trace; |
228 | ||
ae63b31e | 229 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 230 | |
ff451961 SRRH |
231 | int trace_array_get(struct trace_array *this_tr) |
232 | { | |
233 | struct trace_array *tr; | |
234 | int ret = -ENODEV; | |
235 | ||
236 | mutex_lock(&trace_types_lock); | |
237 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
238 | if (tr == this_tr) { | |
239 | tr->ref++; | |
240 | ret = 0; | |
241 | break; | |
242 | } | |
243 | } | |
244 | mutex_unlock(&trace_types_lock); | |
245 | ||
246 | return ret; | |
247 | } | |
248 | ||
249 | static void __trace_array_put(struct trace_array *this_tr) | |
250 | { | |
251 | WARN_ON(!this_tr->ref); | |
252 | this_tr->ref--; | |
253 | } | |
254 | ||
255 | void trace_array_put(struct trace_array *this_tr) | |
256 | { | |
257 | mutex_lock(&trace_types_lock); | |
258 | __trace_array_put(this_tr); | |
259 | mutex_unlock(&trace_types_lock); | |
260 | } | |
261 | ||
f306cc82 TZ |
262 | int filter_check_discard(struct ftrace_event_file *file, void *rec, |
263 | struct ring_buffer *buffer, | |
264 | struct ring_buffer_event *event) | |
eb02ce01 | 265 | { |
f306cc82 TZ |
266 | if (unlikely(file->flags & FTRACE_EVENT_FL_FILTERED) && |
267 | !filter_match_preds(file->filter, rec)) { | |
268 | ring_buffer_discard_commit(buffer, event); | |
269 | return 1; | |
270 | } | |
271 | ||
272 | return 0; | |
273 | } | |
274 | EXPORT_SYMBOL_GPL(filter_check_discard); | |
275 | ||
276 | int call_filter_check_discard(struct ftrace_event_call *call, void *rec, | |
277 | struct ring_buffer *buffer, | |
278 | struct ring_buffer_event *event) | |
279 | { | |
280 | if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && | |
281 | !filter_match_preds(call->filter, rec)) { | |
282 | ring_buffer_discard_commit(buffer, event); | |
283 | return 1; | |
284 | } | |
285 | ||
286 | return 0; | |
eb02ce01 | 287 | } |
f306cc82 | 288 | EXPORT_SYMBOL_GPL(call_filter_check_discard); |
eb02ce01 | 289 | |
ad1438a0 | 290 | static cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) |
37886f6a SR |
291 | { |
292 | u64 ts; | |
293 | ||
294 | /* Early boot up does not have a buffer yet */ | |
9457158b | 295 | if (!buf->buffer) |
37886f6a SR |
296 | return trace_clock_local(); |
297 | ||
9457158b AL |
298 | ts = ring_buffer_time_stamp(buf->buffer, cpu); |
299 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); | |
37886f6a SR |
300 | |
301 | return ts; | |
302 | } | |
bc0c38d1 | 303 | |
9457158b AL |
304 | cycle_t ftrace_now(int cpu) |
305 | { | |
306 | return buffer_ftrace_now(&global_trace.trace_buffer, cpu); | |
307 | } | |
308 | ||
10246fa3 SRRH |
309 | /** |
310 | * tracing_is_enabled - Show if global_trace has been disabled | |
311 | * | |
312 | * Shows if the global trace has been enabled or not. It uses the | |
313 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
314 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
315 | * need to know the accurate state, use tracing_is_on() which is a little | |
316 | * slower, but accurate. | |
317 | */ | |
9036990d SR |
318 | int tracing_is_enabled(void) |
319 | { | |
10246fa3 SRRH |
320 | /* |
321 | * For quick access (irqsoff uses this in fast path), just | |
322 | * return the mirror variable of the state of the ring buffer. | |
323 | * It's a little racy, but we don't really care. | |
324 | */ | |
325 | smp_rmb(); | |
326 | return !global_trace.buffer_disabled; | |
9036990d SR |
327 | } |
328 | ||
4fcdae83 | 329 | /* |
3928a8a2 SR |
330 | * trace_buf_size is the size in bytes that is allocated |
331 | * for a buffer. Note, the number of bytes is always rounded | |
332 | * to page size. | |
3f5a54e3 SR |
333 | * |
334 | * This number is purposely set to a low number of 16384. | |
335 | * If the dump on oops happens, it will be much appreciated | |
336 | * to not have to wait for all that output. Anyway this can be | |
337 | * boot time and run time configurable. | |
4fcdae83 | 338 | */ |
3928a8a2 | 339 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 340 | |
3928a8a2 | 341 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 342 | |
4fcdae83 | 343 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 344 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 345 | |
4fcdae83 SR |
346 | /* |
347 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 348 | */ |
a8227415 | 349 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 350 | |
7e53bd42 LJ |
351 | /* |
352 | * serialize the access of the ring buffer | |
353 | * | |
354 | * ring buffer serializes readers, but it is low level protection. | |
355 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
356 | * are not protected by ring buffer. | |
357 | * | |
358 | * The content of events may become garbage if we allow other process consumes | |
359 | * these events concurrently: | |
360 | * A) the page of the consumed events may become a normal page | |
361 | * (not reader page) in ring buffer, and this page will be rewrited | |
362 | * by events producer. | |
363 | * B) The page of the consumed events may become a page for splice_read, | |
364 | * and this page will be returned to system. | |
365 | * | |
366 | * These primitives allow multi process access to different cpu ring buffer | |
367 | * concurrently. | |
368 | * | |
369 | * These primitives don't distinguish read-only and read-consume access. | |
370 | * Multi read-only access are also serialized. | |
371 | */ | |
372 | ||
373 | #ifdef CONFIG_SMP | |
374 | static DECLARE_RWSEM(all_cpu_access_lock); | |
375 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
376 | ||
377 | static inline void trace_access_lock(int cpu) | |
378 | { | |
ae3b5093 | 379 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
380 | /* gain it for accessing the whole ring buffer. */ |
381 | down_write(&all_cpu_access_lock); | |
382 | } else { | |
383 | /* gain it for accessing a cpu ring buffer. */ | |
384 | ||
ae3b5093 | 385 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
386 | down_read(&all_cpu_access_lock); |
387 | ||
388 | /* Secondly block other access to this @cpu ring buffer. */ | |
389 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
390 | } | |
391 | } | |
392 | ||
393 | static inline void trace_access_unlock(int cpu) | |
394 | { | |
ae3b5093 | 395 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
396 | up_write(&all_cpu_access_lock); |
397 | } else { | |
398 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
399 | up_read(&all_cpu_access_lock); | |
400 | } | |
401 | } | |
402 | ||
403 | static inline void trace_access_lock_init(void) | |
404 | { | |
405 | int cpu; | |
406 | ||
407 | for_each_possible_cpu(cpu) | |
408 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
409 | } | |
410 | ||
411 | #else | |
412 | ||
413 | static DEFINE_MUTEX(access_lock); | |
414 | ||
415 | static inline void trace_access_lock(int cpu) | |
416 | { | |
417 | (void)cpu; | |
418 | mutex_lock(&access_lock); | |
419 | } | |
420 | ||
421 | static inline void trace_access_unlock(int cpu) | |
422 | { | |
423 | (void)cpu; | |
424 | mutex_unlock(&access_lock); | |
425 | } | |
426 | ||
427 | static inline void trace_access_lock_init(void) | |
428 | { | |
429 | } | |
430 | ||
431 | #endif | |
432 | ||
ee6bce52 | 433 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 434 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 435 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 | 436 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
328df475 | 437 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION; |
e7e2ee89 | 438 | |
5280bcef | 439 | static void tracer_tracing_on(struct trace_array *tr) |
10246fa3 SRRH |
440 | { |
441 | if (tr->trace_buffer.buffer) | |
442 | ring_buffer_record_on(tr->trace_buffer.buffer); | |
443 | /* | |
444 | * This flag is looked at when buffers haven't been allocated | |
445 | * yet, or by some tracers (like irqsoff), that just want to | |
446 | * know if the ring buffer has been disabled, but it can handle | |
447 | * races of where it gets disabled but we still do a record. | |
448 | * As the check is in the fast path of the tracers, it is more | |
449 | * important to be fast than accurate. | |
450 | */ | |
451 | tr->buffer_disabled = 0; | |
452 | /* Make the flag seen by readers */ | |
453 | smp_wmb(); | |
454 | } | |
455 | ||
499e5470 SR |
456 | /** |
457 | * tracing_on - enable tracing buffers | |
458 | * | |
459 | * This function enables tracing buffers that may have been | |
460 | * disabled with tracing_off. | |
461 | */ | |
462 | void tracing_on(void) | |
463 | { | |
10246fa3 | 464 | tracer_tracing_on(&global_trace); |
499e5470 SR |
465 | } |
466 | EXPORT_SYMBOL_GPL(tracing_on); | |
467 | ||
09ae7234 SRRH |
468 | /** |
469 | * __trace_puts - write a constant string into the trace buffer. | |
470 | * @ip: The address of the caller | |
471 | * @str: The constant string to write | |
472 | * @size: The size of the string. | |
473 | */ | |
474 | int __trace_puts(unsigned long ip, const char *str, int size) | |
475 | { | |
476 | struct ring_buffer_event *event; | |
477 | struct ring_buffer *buffer; | |
478 | struct print_entry *entry; | |
479 | unsigned long irq_flags; | |
480 | int alloc; | |
8abfb872 J |
481 | int pc; |
482 | ||
f0160a5a J |
483 | if (!(trace_flags & TRACE_ITER_PRINTK)) |
484 | return 0; | |
485 | ||
8abfb872 | 486 | pc = preempt_count(); |
09ae7234 | 487 | |
3132e107 SRRH |
488 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
489 | return 0; | |
490 | ||
09ae7234 SRRH |
491 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ |
492 | ||
493 | local_save_flags(irq_flags); | |
494 | buffer = global_trace.trace_buffer.buffer; | |
495 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, | |
8abfb872 | 496 | irq_flags, pc); |
09ae7234 SRRH |
497 | if (!event) |
498 | return 0; | |
499 | ||
500 | entry = ring_buffer_event_data(event); | |
501 | entry->ip = ip; | |
502 | ||
503 | memcpy(&entry->buf, str, size); | |
504 | ||
505 | /* Add a newline if necessary */ | |
506 | if (entry->buf[size - 1] != '\n') { | |
507 | entry->buf[size] = '\n'; | |
508 | entry->buf[size + 1] = '\0'; | |
509 | } else | |
510 | entry->buf[size] = '\0'; | |
511 | ||
512 | __buffer_unlock_commit(buffer, event); | |
8abfb872 | 513 | ftrace_trace_stack(buffer, irq_flags, 4, pc); |
09ae7234 SRRH |
514 | |
515 | return size; | |
516 | } | |
517 | EXPORT_SYMBOL_GPL(__trace_puts); | |
518 | ||
519 | /** | |
520 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
521 | * @ip: The address of the caller | |
522 | * @str: The constant string to write to the buffer to | |
523 | */ | |
524 | int __trace_bputs(unsigned long ip, const char *str) | |
525 | { | |
526 | struct ring_buffer_event *event; | |
527 | struct ring_buffer *buffer; | |
528 | struct bputs_entry *entry; | |
529 | unsigned long irq_flags; | |
530 | int size = sizeof(struct bputs_entry); | |
8abfb872 J |
531 | int pc; |
532 | ||
f0160a5a J |
533 | if (!(trace_flags & TRACE_ITER_PRINTK)) |
534 | return 0; | |
535 | ||
8abfb872 | 536 | pc = preempt_count(); |
09ae7234 | 537 | |
3132e107 SRRH |
538 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
539 | return 0; | |
540 | ||
09ae7234 SRRH |
541 | local_save_flags(irq_flags); |
542 | buffer = global_trace.trace_buffer.buffer; | |
543 | event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, | |
8abfb872 | 544 | irq_flags, pc); |
09ae7234 SRRH |
545 | if (!event) |
546 | return 0; | |
547 | ||
548 | entry = ring_buffer_event_data(event); | |
549 | entry->ip = ip; | |
550 | entry->str = str; | |
551 | ||
552 | __buffer_unlock_commit(buffer, event); | |
8abfb872 | 553 | ftrace_trace_stack(buffer, irq_flags, 4, pc); |
09ae7234 SRRH |
554 | |
555 | return 1; | |
556 | } | |
557 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
558 | ||
ad909e21 SRRH |
559 | #ifdef CONFIG_TRACER_SNAPSHOT |
560 | /** | |
561 | * trace_snapshot - take a snapshot of the current buffer. | |
562 | * | |
563 | * This causes a swap between the snapshot buffer and the current live | |
564 | * tracing buffer. You can use this to take snapshots of the live | |
565 | * trace when some condition is triggered, but continue to trace. | |
566 | * | |
567 | * Note, make sure to allocate the snapshot with either | |
568 | * a tracing_snapshot_alloc(), or by doing it manually | |
569 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
570 | * | |
571 | * If the snapshot buffer is not allocated, it will stop tracing. | |
572 | * Basically making a permanent snapshot. | |
573 | */ | |
574 | void tracing_snapshot(void) | |
575 | { | |
576 | struct trace_array *tr = &global_trace; | |
577 | struct tracer *tracer = tr->current_trace; | |
578 | unsigned long flags; | |
579 | ||
1b22e382 SRRH |
580 | if (in_nmi()) { |
581 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
582 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
583 | return; | |
584 | } | |
585 | ||
ad909e21 | 586 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
587 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
588 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
589 | tracing_off(); |
590 | return; | |
591 | } | |
592 | ||
593 | /* Note, snapshot can not be used when the tracer uses it */ | |
594 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
595 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
596 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
597 | return; |
598 | } | |
599 | ||
600 | local_irq_save(flags); | |
601 | update_max_tr(tr, current, smp_processor_id()); | |
602 | local_irq_restore(flags); | |
603 | } | |
1b22e382 | 604 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
605 | |
606 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
607 | struct trace_buffer *size_buf, int cpu_id); | |
3209cff4 SRRH |
608 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); |
609 | ||
610 | static int alloc_snapshot(struct trace_array *tr) | |
611 | { | |
612 | int ret; | |
613 | ||
614 | if (!tr->allocated_snapshot) { | |
615 | ||
616 | /* allocate spare buffer */ | |
617 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
618 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
619 | if (ret < 0) | |
620 | return ret; | |
621 | ||
622 | tr->allocated_snapshot = true; | |
623 | } | |
624 | ||
625 | return 0; | |
626 | } | |
627 | ||
ad1438a0 | 628 | static void free_snapshot(struct trace_array *tr) |
3209cff4 SRRH |
629 | { |
630 | /* | |
631 | * We don't free the ring buffer. instead, resize it because | |
632 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
633 | * we want preserve it. | |
634 | */ | |
635 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
636 | set_buffer_entries(&tr->max_buffer, 1); | |
637 | tracing_reset_online_cpus(&tr->max_buffer); | |
638 | tr->allocated_snapshot = false; | |
639 | } | |
ad909e21 | 640 | |
93e31ffb TZ |
641 | /** |
642 | * tracing_alloc_snapshot - allocate snapshot buffer. | |
643 | * | |
644 | * This only allocates the snapshot buffer if it isn't already | |
645 | * allocated - it doesn't also take a snapshot. | |
646 | * | |
647 | * This is meant to be used in cases where the snapshot buffer needs | |
648 | * to be set up for events that can't sleep but need to be able to | |
649 | * trigger a snapshot. | |
650 | */ | |
651 | int tracing_alloc_snapshot(void) | |
652 | { | |
653 | struct trace_array *tr = &global_trace; | |
654 | int ret; | |
655 | ||
656 | ret = alloc_snapshot(tr); | |
657 | WARN_ON(ret < 0); | |
658 | ||
659 | return ret; | |
660 | } | |
661 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
662 | ||
ad909e21 SRRH |
663 | /** |
664 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
665 | * | |
666 | * This is similar to trace_snapshot(), but it will allocate the | |
667 | * snapshot buffer if it isn't already allocated. Use this only | |
668 | * where it is safe to sleep, as the allocation may sleep. | |
669 | * | |
670 | * This causes a swap between the snapshot buffer and the current live | |
671 | * tracing buffer. You can use this to take snapshots of the live | |
672 | * trace when some condition is triggered, but continue to trace. | |
673 | */ | |
674 | void tracing_snapshot_alloc(void) | |
675 | { | |
ad909e21 SRRH |
676 | int ret; |
677 | ||
93e31ffb TZ |
678 | ret = tracing_alloc_snapshot(); |
679 | if (ret < 0) | |
3209cff4 | 680 | return; |
ad909e21 SRRH |
681 | |
682 | tracing_snapshot(); | |
683 | } | |
1b22e382 | 684 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
685 | #else |
686 | void tracing_snapshot(void) | |
687 | { | |
688 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
689 | } | |
1b22e382 | 690 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
93e31ffb TZ |
691 | int tracing_alloc_snapshot(void) |
692 | { | |
693 | WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); | |
694 | return -ENODEV; | |
695 | } | |
696 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
ad909e21 SRRH |
697 | void tracing_snapshot_alloc(void) |
698 | { | |
699 | /* Give warning */ | |
700 | tracing_snapshot(); | |
701 | } | |
1b22e382 | 702 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
703 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
704 | ||
5280bcef | 705 | static void tracer_tracing_off(struct trace_array *tr) |
10246fa3 SRRH |
706 | { |
707 | if (tr->trace_buffer.buffer) | |
708 | ring_buffer_record_off(tr->trace_buffer.buffer); | |
709 | /* | |
710 | * This flag is looked at when buffers haven't been allocated | |
711 | * yet, or by some tracers (like irqsoff), that just want to | |
712 | * know if the ring buffer has been disabled, but it can handle | |
713 | * races of where it gets disabled but we still do a record. | |
714 | * As the check is in the fast path of the tracers, it is more | |
715 | * important to be fast than accurate. | |
716 | */ | |
717 | tr->buffer_disabled = 1; | |
718 | /* Make the flag seen by readers */ | |
719 | smp_wmb(); | |
720 | } | |
721 | ||
499e5470 SR |
722 | /** |
723 | * tracing_off - turn off tracing buffers | |
724 | * | |
725 | * This function stops the tracing buffers from recording data. | |
726 | * It does not disable any overhead the tracers themselves may | |
727 | * be causing. This function simply causes all recording to | |
728 | * the ring buffers to fail. | |
729 | */ | |
730 | void tracing_off(void) | |
731 | { | |
10246fa3 | 732 | tracer_tracing_off(&global_trace); |
499e5470 SR |
733 | } |
734 | EXPORT_SYMBOL_GPL(tracing_off); | |
735 | ||
de7edd31 SRRH |
736 | void disable_trace_on_warning(void) |
737 | { | |
738 | if (__disable_trace_on_warning) | |
739 | tracing_off(); | |
740 | } | |
741 | ||
10246fa3 SRRH |
742 | /** |
743 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
744 | * @tr : the trace array to know if ring buffer is enabled | |
745 | * | |
746 | * Shows real state of the ring buffer if it is enabled or not. | |
747 | */ | |
5280bcef | 748 | static int tracer_tracing_is_on(struct trace_array *tr) |
10246fa3 SRRH |
749 | { |
750 | if (tr->trace_buffer.buffer) | |
751 | return ring_buffer_record_is_on(tr->trace_buffer.buffer); | |
752 | return !tr->buffer_disabled; | |
753 | } | |
754 | ||
499e5470 SR |
755 | /** |
756 | * tracing_is_on - show state of ring buffers enabled | |
757 | */ | |
758 | int tracing_is_on(void) | |
759 | { | |
10246fa3 | 760 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
761 | } |
762 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
763 | ||
3928a8a2 | 764 | static int __init set_buf_size(char *str) |
bc0c38d1 | 765 | { |
3928a8a2 | 766 | unsigned long buf_size; |
c6caeeb1 | 767 | |
bc0c38d1 SR |
768 | if (!str) |
769 | return 0; | |
9d612bef | 770 | buf_size = memparse(str, &str); |
c6caeeb1 | 771 | /* nr_entries can not be zero */ |
9d612bef | 772 | if (buf_size == 0) |
c6caeeb1 | 773 | return 0; |
3928a8a2 | 774 | trace_buf_size = buf_size; |
bc0c38d1 SR |
775 | return 1; |
776 | } | |
3928a8a2 | 777 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 778 | |
0e950173 TB |
779 | static int __init set_tracing_thresh(char *str) |
780 | { | |
87abb3b1 | 781 | unsigned long threshold; |
0e950173 TB |
782 | int ret; |
783 | ||
784 | if (!str) | |
785 | return 0; | |
bcd83ea6 | 786 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
787 | if (ret < 0) |
788 | return 0; | |
87abb3b1 | 789 | tracing_thresh = threshold * 1000; |
0e950173 TB |
790 | return 1; |
791 | } | |
792 | __setup("tracing_thresh=", set_tracing_thresh); | |
793 | ||
57f50be1 SR |
794 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
795 | { | |
796 | return nsecs / 1000; | |
797 | } | |
798 | ||
4fcdae83 | 799 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
800 | static const char *trace_options[] = { |
801 | "print-parent", | |
802 | "sym-offset", | |
803 | "sym-addr", | |
804 | "verbose", | |
f9896bf3 | 805 | "raw", |
5e3ca0ec | 806 | "hex", |
cb0f12aa | 807 | "bin", |
2a2cc8f7 | 808 | "block", |
86387f7e | 809 | "stacktrace", |
5e1607a0 | 810 | "trace_printk", |
b2a866f9 | 811 | "ftrace_preempt", |
9f029e83 | 812 | "branch", |
12ef7d44 | 813 | "annotate", |
02b67518 | 814 | "userstacktrace", |
b54d3de9 | 815 | "sym-userobj", |
66896a85 | 816 | "printk-msg-only", |
c4a8e8be | 817 | "context-info", |
c032ef64 | 818 | "latency-format", |
be6f164a | 819 | "sleep-time", |
a2a16d6a | 820 | "graph-time", |
e870e9a1 | 821 | "record-cmd", |
750912fa | 822 | "overwrite", |
cf30cf67 | 823 | "disable_on_free", |
77271ce4 | 824 | "irq-info", |
5224c3a3 | 825 | "markers", |
328df475 | 826 | "function-trace", |
bc0c38d1 SR |
827 | NULL |
828 | }; | |
829 | ||
5079f326 Z |
830 | static struct { |
831 | u64 (*func)(void); | |
832 | const char *name; | |
8be0709f | 833 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 834 | } trace_clocks[] = { |
1b3e5c09 TG |
835 | { trace_clock_local, "local", 1 }, |
836 | { trace_clock_global, "global", 1 }, | |
837 | { trace_clock_counter, "counter", 0 }, | |
e7fda6c4 | 838 | { trace_clock_jiffies, "uptime", 0 }, |
1b3e5c09 TG |
839 | { trace_clock, "perf", 1 }, |
840 | { ktime_get_mono_fast_ns, "mono", 1 }, | |
8cbd9cc6 | 841 | ARCH_TRACE_CLOCKS |
5079f326 Z |
842 | }; |
843 | ||
b63f39ea | 844 | /* |
845 | * trace_parser_get_init - gets the buffer for trace parser | |
846 | */ | |
847 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
848 | { | |
849 | memset(parser, 0, sizeof(*parser)); | |
850 | ||
851 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
852 | if (!parser->buffer) | |
853 | return 1; | |
854 | ||
855 | parser->size = size; | |
856 | return 0; | |
857 | } | |
858 | ||
859 | /* | |
860 | * trace_parser_put - frees the buffer for trace parser | |
861 | */ | |
862 | void trace_parser_put(struct trace_parser *parser) | |
863 | { | |
864 | kfree(parser->buffer); | |
865 | } | |
866 | ||
867 | /* | |
868 | * trace_get_user - reads the user input string separated by space | |
869 | * (matched by isspace(ch)) | |
870 | * | |
871 | * For each string found the 'struct trace_parser' is updated, | |
872 | * and the function returns. | |
873 | * | |
874 | * Returns number of bytes read. | |
875 | * | |
876 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
877 | */ | |
878 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
879 | size_t cnt, loff_t *ppos) | |
880 | { | |
881 | char ch; | |
882 | size_t read = 0; | |
883 | ssize_t ret; | |
884 | ||
885 | if (!*ppos) | |
886 | trace_parser_clear(parser); | |
887 | ||
888 | ret = get_user(ch, ubuf++); | |
889 | if (ret) | |
890 | goto out; | |
891 | ||
892 | read++; | |
893 | cnt--; | |
894 | ||
895 | /* | |
896 | * The parser is not finished with the last write, | |
897 | * continue reading the user input without skipping spaces. | |
898 | */ | |
899 | if (!parser->cont) { | |
900 | /* skip white space */ | |
901 | while (cnt && isspace(ch)) { | |
902 | ret = get_user(ch, ubuf++); | |
903 | if (ret) | |
904 | goto out; | |
905 | read++; | |
906 | cnt--; | |
907 | } | |
908 | ||
909 | /* only spaces were written */ | |
910 | if (isspace(ch)) { | |
911 | *ppos += read; | |
912 | ret = read; | |
913 | goto out; | |
914 | } | |
915 | ||
916 | parser->idx = 0; | |
917 | } | |
918 | ||
919 | /* read the non-space input */ | |
920 | while (cnt && !isspace(ch)) { | |
3c235a33 | 921 | if (parser->idx < parser->size - 1) |
b63f39ea | 922 | parser->buffer[parser->idx++] = ch; |
923 | else { | |
924 | ret = -EINVAL; | |
925 | goto out; | |
926 | } | |
927 | ret = get_user(ch, ubuf++); | |
928 | if (ret) | |
929 | goto out; | |
930 | read++; | |
931 | cnt--; | |
932 | } | |
933 | ||
934 | /* We either got finished input or we have to wait for another call. */ | |
935 | if (isspace(ch)) { | |
936 | parser->buffer[parser->idx] = 0; | |
937 | parser->cont = false; | |
057db848 | 938 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 939 | parser->cont = true; |
940 | parser->buffer[parser->idx++] = ch; | |
057db848 SR |
941 | } else { |
942 | ret = -EINVAL; | |
943 | goto out; | |
b63f39ea | 944 | } |
945 | ||
946 | *ppos += read; | |
947 | ret = read; | |
948 | ||
949 | out: | |
950 | return ret; | |
951 | } | |
952 | ||
3a161d99 | 953 | /* TODO add a seq_buf_to_buffer() */ |
b8b94265 | 954 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
955 | { |
956 | int len; | |
3c56819b | 957 | |
5ac48378 | 958 | if (trace_seq_used(s) <= s->seq.readpos) |
3c56819b EGM |
959 | return -EBUSY; |
960 | ||
5ac48378 | 961 | len = trace_seq_used(s) - s->seq.readpos; |
3c56819b EGM |
962 | if (cnt > len) |
963 | cnt = len; | |
3a161d99 | 964 | memcpy(buf, s->buffer + s->seq.readpos, cnt); |
3c56819b | 965 | |
3a161d99 | 966 | s->seq.readpos += cnt; |
3c56819b EGM |
967 | return cnt; |
968 | } | |
969 | ||
0e950173 TB |
970 | unsigned long __read_mostly tracing_thresh; |
971 | ||
5d4a9dba | 972 | #ifdef CONFIG_TRACER_MAX_TRACE |
5d4a9dba SR |
973 | /* |
974 | * Copy the new maximum trace into the separate maximum-trace | |
975 | * structure. (this way the maximum trace is permanently saved, | |
976 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
977 | */ | |
978 | static void | |
979 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
980 | { | |
12883efb SRRH |
981 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
982 | struct trace_buffer *max_buf = &tr->max_buffer; | |
983 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
984 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 985 | |
12883efb SRRH |
986 | max_buf->cpu = cpu; |
987 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 988 | |
6d9b3fa5 | 989 | max_data->saved_latency = tr->max_latency; |
8248ac05 SR |
990 | max_data->critical_start = data->critical_start; |
991 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 992 | |
1acaa1b2 | 993 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 994 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
995 | /* |
996 | * If tsk == current, then use current_uid(), as that does not use | |
997 | * RCU. The irq tracer can be called out of RCU scope. | |
998 | */ | |
999 | if (tsk == current) | |
1000 | max_data->uid = current_uid(); | |
1001 | else | |
1002 | max_data->uid = task_uid(tsk); | |
1003 | ||
8248ac05 SR |
1004 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
1005 | max_data->policy = tsk->policy; | |
1006 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
1007 | |
1008 | /* record this tasks comm */ | |
1009 | tracing_record_cmdline(tsk); | |
1010 | } | |
1011 | ||
4fcdae83 SR |
1012 | /** |
1013 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
1014 | * @tr: tracer | |
1015 | * @tsk: the task with the latency | |
1016 | * @cpu: The cpu that initiated the trace. | |
1017 | * | |
1018 | * Flip the buffers between the @tr and the max_tr and record information | |
1019 | * about which task was the cause of this latency. | |
1020 | */ | |
e309b41d | 1021 | void |
bc0c38d1 SR |
1022 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1023 | { | |
2721e72d | 1024 | struct ring_buffer *buf; |
bc0c38d1 | 1025 | |
2b6080f2 | 1026 | if (tr->stop_count) |
b8de7bd1 SR |
1027 | return; |
1028 | ||
4c11d7ae | 1029 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 1030 | |
45ad21ca | 1031 | if (!tr->allocated_snapshot) { |
debdd57f | 1032 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 1033 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 1034 | return; |
debdd57f | 1035 | } |
34600f0e | 1036 | |
0b9b12c1 | 1037 | arch_spin_lock(&tr->max_lock); |
3928a8a2 | 1038 | |
12883efb SRRH |
1039 | buf = tr->trace_buffer.buffer; |
1040 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
1041 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 1042 | |
bc0c38d1 | 1043 | __update_max_tr(tr, tsk, cpu); |
0b9b12c1 | 1044 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 SR |
1045 | } |
1046 | ||
1047 | /** | |
1048 | * update_max_tr_single - only copy one trace over, and reset the rest | |
1049 | * @tr - tracer | |
1050 | * @tsk - task with the latency | |
1051 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
1052 | * |
1053 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1054 | */ |
e309b41d | 1055 | void |
bc0c38d1 SR |
1056 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1057 | { | |
3928a8a2 | 1058 | int ret; |
bc0c38d1 | 1059 | |
2b6080f2 | 1060 | if (tr->stop_count) |
b8de7bd1 SR |
1061 | return; |
1062 | ||
4c11d7ae | 1063 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1064 | if (!tr->allocated_snapshot) { |
2930e04d | 1065 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1066 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1067 | return; |
2930e04d | 1068 | } |
ef710e10 | 1069 | |
0b9b12c1 | 1070 | arch_spin_lock(&tr->max_lock); |
bc0c38d1 | 1071 | |
12883efb | 1072 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 1073 | |
e8165dbb SR |
1074 | if (ret == -EBUSY) { |
1075 | /* | |
1076 | * We failed to swap the buffer due to a commit taking | |
1077 | * place on this CPU. We fail to record, but we reset | |
1078 | * the max trace buffer (no one writes directly to it) | |
1079 | * and flag that it failed. | |
1080 | */ | |
12883efb | 1081 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1082 | "Failed to swap buffers due to commit in progress\n"); |
1083 | } | |
1084 | ||
e8165dbb | 1085 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1086 | |
1087 | __update_max_tr(tr, tsk, cpu); | |
0b9b12c1 | 1088 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 | 1089 | } |
5d4a9dba | 1090 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1091 | |
e30f53aa | 1092 | static int wait_on_pipe(struct trace_iterator *iter, bool full) |
0d5c6e1c | 1093 | { |
15693458 SRRH |
1094 | /* Iterators are static, they should be filled or empty */ |
1095 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
8b8b3683 | 1096 | return 0; |
0d5c6e1c | 1097 | |
e30f53aa RV |
1098 | return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file, |
1099 | full); | |
0d5c6e1c SR |
1100 | } |
1101 | ||
f4e781c0 SRRH |
1102 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
1103 | static int run_tracer_selftest(struct tracer *type) | |
1104 | { | |
1105 | struct trace_array *tr = &global_trace; | |
1106 | struct tracer *saved_tracer = tr->current_trace; | |
1107 | int ret; | |
0d5c6e1c | 1108 | |
f4e781c0 SRRH |
1109 | if (!type->selftest || tracing_selftest_disabled) |
1110 | return 0; | |
0d5c6e1c SR |
1111 | |
1112 | /* | |
f4e781c0 SRRH |
1113 | * Run a selftest on this tracer. |
1114 | * Here we reset the trace buffer, and set the current | |
1115 | * tracer to be this tracer. The tracer can then run some | |
1116 | * internal tracing to verify that everything is in order. | |
1117 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1118 | */ |
f4e781c0 | 1119 | tracing_reset_online_cpus(&tr->trace_buffer); |
0d5c6e1c | 1120 | |
f4e781c0 SRRH |
1121 | tr->current_trace = type; |
1122 | ||
1123 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1124 | if (type->use_max_tr) { | |
1125 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1126 | if (ring_buffer_expanded) | |
1127 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1128 | RING_BUFFER_ALL_CPUS); | |
1129 | tr->allocated_snapshot = true; | |
1130 | } | |
1131 | #endif | |
1132 | ||
1133 | /* the test is responsible for initializing and enabling */ | |
1134 | pr_info("Testing tracer %s: ", type->name); | |
1135 | ret = type->selftest(type, tr); | |
1136 | /* the test is responsible for resetting too */ | |
1137 | tr->current_trace = saved_tracer; | |
1138 | if (ret) { | |
1139 | printk(KERN_CONT "FAILED!\n"); | |
1140 | /* Add the warning after printing 'FAILED' */ | |
1141 | WARN_ON(1); | |
1142 | return -1; | |
1143 | } | |
1144 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1145 | tracing_reset_online_cpus(&tr->trace_buffer); | |
1146 | ||
1147 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1148 | if (type->use_max_tr) { | |
1149 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1150 | |
f4e781c0 SRRH |
1151 | /* Shrink the max buffer again */ |
1152 | if (ring_buffer_expanded) | |
1153 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1154 | RING_BUFFER_ALL_CPUS); | |
1155 | } | |
1156 | #endif | |
1157 | ||
1158 | printk(KERN_CONT "PASSED\n"); | |
1159 | return 0; | |
1160 | } | |
1161 | #else | |
1162 | static inline int run_tracer_selftest(struct tracer *type) | |
1163 | { | |
1164 | return 0; | |
0d5c6e1c | 1165 | } |
f4e781c0 | 1166 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 1167 | |
4fcdae83 SR |
1168 | /** |
1169 | * register_tracer - register a tracer with the ftrace system. | |
1170 | * @type - the plugin for the tracer | |
1171 | * | |
1172 | * Register a new plugin tracer. | |
1173 | */ | |
bc0c38d1 SR |
1174 | int register_tracer(struct tracer *type) |
1175 | { | |
1176 | struct tracer *t; | |
bc0c38d1 SR |
1177 | int ret = 0; |
1178 | ||
1179 | if (!type->name) { | |
1180 | pr_info("Tracer must have a name\n"); | |
1181 | return -1; | |
1182 | } | |
1183 | ||
24a461d5 | 1184 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
1185 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
1186 | return -1; | |
1187 | } | |
1188 | ||
bc0c38d1 | 1189 | mutex_lock(&trace_types_lock); |
86fa2f60 | 1190 | |
8e1b82e0 FW |
1191 | tracing_selftest_running = true; |
1192 | ||
bc0c38d1 SR |
1193 | for (t = trace_types; t; t = t->next) { |
1194 | if (strcmp(type->name, t->name) == 0) { | |
1195 | /* already found */ | |
ee6c2c1b | 1196 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
1197 | type->name); |
1198 | ret = -1; | |
1199 | goto out; | |
1200 | } | |
1201 | } | |
1202 | ||
adf9f195 FW |
1203 | if (!type->set_flag) |
1204 | type->set_flag = &dummy_set_flag; | |
1205 | if (!type->flags) | |
1206 | type->flags = &dummy_tracer_flags; | |
1207 | else | |
1208 | if (!type->flags->opts) | |
1209 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 | 1210 | |
f4e781c0 SRRH |
1211 | ret = run_tracer_selftest(type); |
1212 | if (ret < 0) | |
1213 | goto out; | |
60a11774 | 1214 | |
bc0c38d1 SR |
1215 | type->next = trace_types; |
1216 | trace_types = type; | |
60a11774 | 1217 | |
bc0c38d1 | 1218 | out: |
8e1b82e0 | 1219 | tracing_selftest_running = false; |
bc0c38d1 SR |
1220 | mutex_unlock(&trace_types_lock); |
1221 | ||
dac74940 SR |
1222 | if (ret || !default_bootup_tracer) |
1223 | goto out_unlock; | |
1224 | ||
ee6c2c1b | 1225 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1226 | goto out_unlock; |
1227 | ||
1228 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1229 | /* Do we want this tracer to start on bootup? */ | |
607e2ea1 | 1230 | tracing_set_tracer(&global_trace, type->name); |
dac74940 SR |
1231 | default_bootup_tracer = NULL; |
1232 | /* disable other selftests, since this will break it. */ | |
55034cd6 | 1233 | tracing_selftest_disabled = true; |
b2821ae6 | 1234 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1235 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1236 | type->name); | |
b2821ae6 | 1237 | #endif |
b2821ae6 | 1238 | |
dac74940 | 1239 | out_unlock: |
bc0c38d1 SR |
1240 | return ret; |
1241 | } | |
1242 | ||
12883efb | 1243 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1244 | { |
12883efb | 1245 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1246 | |
a5416411 HT |
1247 | if (!buffer) |
1248 | return; | |
1249 | ||
f633903a SR |
1250 | ring_buffer_record_disable(buffer); |
1251 | ||
1252 | /* Make sure all commits have finished */ | |
1253 | synchronize_sched(); | |
68179686 | 1254 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1255 | |
1256 | ring_buffer_record_enable(buffer); | |
1257 | } | |
1258 | ||
12883efb | 1259 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1260 | { |
12883efb | 1261 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1262 | int cpu; |
1263 | ||
a5416411 HT |
1264 | if (!buffer) |
1265 | return; | |
1266 | ||
621968cd SR |
1267 | ring_buffer_record_disable(buffer); |
1268 | ||
1269 | /* Make sure all commits have finished */ | |
1270 | synchronize_sched(); | |
1271 | ||
9457158b | 1272 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 PE |
1273 | |
1274 | for_each_online_cpu(cpu) | |
68179686 | 1275 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1276 | |
1277 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1278 | } |
1279 | ||
09d8091c | 1280 | /* Must have trace_types_lock held */ |
873c642f | 1281 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1282 | { |
873c642f SRRH |
1283 | struct trace_array *tr; |
1284 | ||
873c642f | 1285 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
12883efb SRRH |
1286 | tracing_reset_online_cpus(&tr->trace_buffer); |
1287 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1288 | tracing_reset_online_cpus(&tr->max_buffer); | |
1289 | #endif | |
873c642f | 1290 | } |
9456f0fa SR |
1291 | } |
1292 | ||
939c7a4f | 1293 | #define SAVED_CMDLINES_DEFAULT 128 |
2c7eea4c | 1294 | #define NO_CMDLINE_MAP UINT_MAX |
edc35bd7 | 1295 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
939c7a4f YY |
1296 | struct saved_cmdlines_buffer { |
1297 | unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
1298 | unsigned *map_cmdline_to_pid; | |
1299 | unsigned cmdline_num; | |
1300 | int cmdline_idx; | |
1301 | char *saved_cmdlines; | |
1302 | }; | |
1303 | static struct saved_cmdlines_buffer *savedcmd; | |
25b0b44a | 1304 | |
25b0b44a | 1305 | /* temporary disable recording */ |
4fd27358 | 1306 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 | 1307 | |
939c7a4f YY |
1308 | static inline char *get_saved_cmdlines(int idx) |
1309 | { | |
1310 | return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN]; | |
1311 | } | |
1312 | ||
1313 | static inline void set_cmdline(int idx, const char *cmdline) | |
bc0c38d1 | 1314 | { |
939c7a4f YY |
1315 | memcpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); |
1316 | } | |
1317 | ||
1318 | static int allocate_cmdlines_buffer(unsigned int val, | |
1319 | struct saved_cmdlines_buffer *s) | |
1320 | { | |
1321 | s->map_cmdline_to_pid = kmalloc(val * sizeof(*s->map_cmdline_to_pid), | |
1322 | GFP_KERNEL); | |
1323 | if (!s->map_cmdline_to_pid) | |
1324 | return -ENOMEM; | |
1325 | ||
1326 | s->saved_cmdlines = kmalloc(val * TASK_COMM_LEN, GFP_KERNEL); | |
1327 | if (!s->saved_cmdlines) { | |
1328 | kfree(s->map_cmdline_to_pid); | |
1329 | return -ENOMEM; | |
1330 | } | |
1331 | ||
1332 | s->cmdline_idx = 0; | |
1333 | s->cmdline_num = val; | |
1334 | memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP, | |
1335 | sizeof(s->map_pid_to_cmdline)); | |
1336 | memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP, | |
1337 | val * sizeof(*s->map_cmdline_to_pid)); | |
1338 | ||
1339 | return 0; | |
1340 | } | |
1341 | ||
1342 | static int trace_create_savedcmd(void) | |
1343 | { | |
1344 | int ret; | |
1345 | ||
a6af8fbf | 1346 | savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL); |
939c7a4f YY |
1347 | if (!savedcmd) |
1348 | return -ENOMEM; | |
1349 | ||
1350 | ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd); | |
1351 | if (ret < 0) { | |
1352 | kfree(savedcmd); | |
1353 | savedcmd = NULL; | |
1354 | return -ENOMEM; | |
1355 | } | |
1356 | ||
1357 | return 0; | |
bc0c38d1 SR |
1358 | } |
1359 | ||
b5130b1e CE |
1360 | int is_tracing_stopped(void) |
1361 | { | |
2b6080f2 | 1362 | return global_trace.stop_count; |
b5130b1e CE |
1363 | } |
1364 | ||
0f048701 SR |
1365 | /** |
1366 | * tracing_start - quick start of the tracer | |
1367 | * | |
1368 | * If tracing is enabled but was stopped by tracing_stop, | |
1369 | * this will start the tracer back up. | |
1370 | */ | |
1371 | void tracing_start(void) | |
1372 | { | |
1373 | struct ring_buffer *buffer; | |
1374 | unsigned long flags; | |
1375 | ||
1376 | if (tracing_disabled) | |
1377 | return; | |
1378 | ||
2b6080f2 SR |
1379 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1380 | if (--global_trace.stop_count) { | |
1381 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1382 | /* Someone screwed up their debugging */ |
1383 | WARN_ON_ONCE(1); | |
2b6080f2 | 1384 | global_trace.stop_count = 0; |
b06a8301 | 1385 | } |
0f048701 SR |
1386 | goto out; |
1387 | } | |
1388 | ||
a2f80714 | 1389 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1390 | arch_spin_lock(&global_trace.max_lock); |
0f048701 | 1391 | |
12883efb | 1392 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1393 | if (buffer) |
1394 | ring_buffer_record_enable(buffer); | |
1395 | ||
12883efb SRRH |
1396 | #ifdef CONFIG_TRACER_MAX_TRACE |
1397 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1398 | if (buffer) |
1399 | ring_buffer_record_enable(buffer); | |
12883efb | 1400 | #endif |
0f048701 | 1401 | |
0b9b12c1 | 1402 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1403 | |
0f048701 | 1404 | out: |
2b6080f2 SR |
1405 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1406 | } | |
1407 | ||
1408 | static void tracing_start_tr(struct trace_array *tr) | |
1409 | { | |
1410 | struct ring_buffer *buffer; | |
1411 | unsigned long flags; | |
1412 | ||
1413 | if (tracing_disabled) | |
1414 | return; | |
1415 | ||
1416 | /* If global, we need to also start the max tracer */ | |
1417 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1418 | return tracing_start(); | |
1419 | ||
1420 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1421 | ||
1422 | if (--tr->stop_count) { | |
1423 | if (tr->stop_count < 0) { | |
1424 | /* Someone screwed up their debugging */ | |
1425 | WARN_ON_ONCE(1); | |
1426 | tr->stop_count = 0; | |
1427 | } | |
1428 | goto out; | |
1429 | } | |
1430 | ||
12883efb | 1431 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1432 | if (buffer) |
1433 | ring_buffer_record_enable(buffer); | |
1434 | ||
1435 | out: | |
1436 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1437 | } |
1438 | ||
1439 | /** | |
1440 | * tracing_stop - quick stop of the tracer | |
1441 | * | |
1442 | * Light weight way to stop tracing. Use in conjunction with | |
1443 | * tracing_start. | |
1444 | */ | |
1445 | void tracing_stop(void) | |
1446 | { | |
1447 | struct ring_buffer *buffer; | |
1448 | unsigned long flags; | |
1449 | ||
2b6080f2 SR |
1450 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1451 | if (global_trace.stop_count++) | |
0f048701 SR |
1452 | goto out; |
1453 | ||
a2f80714 | 1454 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1455 | arch_spin_lock(&global_trace.max_lock); |
a2f80714 | 1456 | |
12883efb | 1457 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1458 | if (buffer) |
1459 | ring_buffer_record_disable(buffer); | |
1460 | ||
12883efb SRRH |
1461 | #ifdef CONFIG_TRACER_MAX_TRACE |
1462 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1463 | if (buffer) |
1464 | ring_buffer_record_disable(buffer); | |
12883efb | 1465 | #endif |
0f048701 | 1466 | |
0b9b12c1 | 1467 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1468 | |
0f048701 | 1469 | out: |
2b6080f2 SR |
1470 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1471 | } | |
1472 | ||
1473 | static void tracing_stop_tr(struct trace_array *tr) | |
1474 | { | |
1475 | struct ring_buffer *buffer; | |
1476 | unsigned long flags; | |
1477 | ||
1478 | /* If global, we need to also stop the max tracer */ | |
1479 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1480 | return tracing_stop(); | |
1481 | ||
1482 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1483 | if (tr->stop_count++) | |
1484 | goto out; | |
1485 | ||
12883efb | 1486 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1487 | if (buffer) |
1488 | ring_buffer_record_disable(buffer); | |
1489 | ||
1490 | out: | |
1491 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1492 | } |
1493 | ||
e309b41d | 1494 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1495 | |
379cfdac | 1496 | static int trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1497 | { |
a635cf04 | 1498 | unsigned pid, idx; |
bc0c38d1 SR |
1499 | |
1500 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
379cfdac | 1501 | return 0; |
bc0c38d1 SR |
1502 | |
1503 | /* | |
1504 | * It's not the end of the world if we don't get | |
1505 | * the lock, but we also don't want to spin | |
1506 | * nor do we want to disable interrupts, | |
1507 | * so if we miss here, then better luck next time. | |
1508 | */ | |
0199c4e6 | 1509 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
379cfdac | 1510 | return 0; |
bc0c38d1 | 1511 | |
939c7a4f | 1512 | idx = savedcmd->map_pid_to_cmdline[tsk->pid]; |
2c7eea4c | 1513 | if (idx == NO_CMDLINE_MAP) { |
939c7a4f | 1514 | idx = (savedcmd->cmdline_idx + 1) % savedcmd->cmdline_num; |
bc0c38d1 | 1515 | |
a635cf04 CE |
1516 | /* |
1517 | * Check whether the cmdline buffer at idx has a pid | |
1518 | * mapped. We are going to overwrite that entry so we | |
1519 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1520 | * would read the new comm for the old pid. | |
1521 | */ | |
939c7a4f | 1522 | pid = savedcmd->map_cmdline_to_pid[idx]; |
a635cf04 | 1523 | if (pid != NO_CMDLINE_MAP) |
939c7a4f | 1524 | savedcmd->map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; |
bc0c38d1 | 1525 | |
939c7a4f YY |
1526 | savedcmd->map_cmdline_to_pid[idx] = tsk->pid; |
1527 | savedcmd->map_pid_to_cmdline[tsk->pid] = idx; | |
bc0c38d1 | 1528 | |
939c7a4f | 1529 | savedcmd->cmdline_idx = idx; |
bc0c38d1 SR |
1530 | } |
1531 | ||
939c7a4f | 1532 | set_cmdline(idx, tsk->comm); |
bc0c38d1 | 1533 | |
0199c4e6 | 1534 | arch_spin_unlock(&trace_cmdline_lock); |
379cfdac SRRH |
1535 | |
1536 | return 1; | |
bc0c38d1 SR |
1537 | } |
1538 | ||
4c27e756 | 1539 | static void __trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1540 | { |
bc0c38d1 SR |
1541 | unsigned map; |
1542 | ||
4ca53085 SR |
1543 | if (!pid) { |
1544 | strcpy(comm, "<idle>"); | |
1545 | return; | |
1546 | } | |
bc0c38d1 | 1547 | |
74bf4076 SR |
1548 | if (WARN_ON_ONCE(pid < 0)) { |
1549 | strcpy(comm, "<XXX>"); | |
1550 | return; | |
1551 | } | |
1552 | ||
4ca53085 SR |
1553 | if (pid > PID_MAX_DEFAULT) { |
1554 | strcpy(comm, "<...>"); | |
1555 | return; | |
1556 | } | |
bc0c38d1 | 1557 | |
939c7a4f | 1558 | map = savedcmd->map_pid_to_cmdline[pid]; |
50d88758 | 1559 | if (map != NO_CMDLINE_MAP) |
939c7a4f | 1560 | strcpy(comm, get_saved_cmdlines(map)); |
50d88758 TG |
1561 | else |
1562 | strcpy(comm, "<...>"); | |
4c27e756 SRRH |
1563 | } |
1564 | ||
1565 | void trace_find_cmdline(int pid, char comm[]) | |
1566 | { | |
1567 | preempt_disable(); | |
1568 | arch_spin_lock(&trace_cmdline_lock); | |
1569 | ||
1570 | __trace_find_cmdline(pid, comm); | |
bc0c38d1 | 1571 | |
0199c4e6 | 1572 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1573 | preempt_enable(); |
bc0c38d1 SR |
1574 | } |
1575 | ||
e309b41d | 1576 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1577 | { |
0fb9656d | 1578 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1579 | return; |
1580 | ||
7ffbd48d SR |
1581 | if (!__this_cpu_read(trace_cmdline_save)) |
1582 | return; | |
1583 | ||
379cfdac SRRH |
1584 | if (trace_save_cmdline(tsk)) |
1585 | __this_cpu_write(trace_cmdline_save, false); | |
bc0c38d1 SR |
1586 | } |
1587 | ||
45dcd8b8 | 1588 | void |
38697053 SR |
1589 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1590 | int pc) | |
bc0c38d1 SR |
1591 | { |
1592 | struct task_struct *tsk = current; | |
bc0c38d1 | 1593 | |
777e208d SR |
1594 | entry->preempt_count = pc & 0xff; |
1595 | entry->pid = (tsk) ? tsk->pid : 0; | |
1596 | entry->flags = | |
9244489a | 1597 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1598 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1599 | #else |
1600 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1601 | #endif | |
bc0c38d1 SR |
1602 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1603 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
e5137b50 PZ |
1604 | (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) | |
1605 | (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0); | |
bc0c38d1 | 1606 | } |
f413cdb8 | 1607 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1608 | |
e77405ad SR |
1609 | struct ring_buffer_event * |
1610 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1611 | int type, | |
1612 | unsigned long len, | |
1613 | unsigned long flags, int pc) | |
51a763dd ACM |
1614 | { |
1615 | struct ring_buffer_event *event; | |
1616 | ||
e77405ad | 1617 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1618 | if (event != NULL) { |
1619 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1620 | ||
1621 | tracing_generic_entry_update(ent, flags, pc); | |
1622 | ent->type = type; | |
1623 | } | |
1624 | ||
1625 | return event; | |
1626 | } | |
51a763dd | 1627 | |
7ffbd48d SR |
1628 | void |
1629 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1630 | { | |
1631 | __this_cpu_write(trace_cmdline_save, true); | |
1632 | ring_buffer_unlock_commit(buffer, event); | |
1633 | } | |
1634 | ||
e77405ad SR |
1635 | static inline void |
1636 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1637 | struct ring_buffer_event *event, | |
0d5c6e1c | 1638 | unsigned long flags, int pc) |
51a763dd | 1639 | { |
7ffbd48d | 1640 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1641 | |
e77405ad SR |
1642 | ftrace_trace_stack(buffer, flags, 6, pc); |
1643 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1644 | } |
1645 | ||
e77405ad SR |
1646 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1647 | struct ring_buffer_event *event, | |
1648 | unsigned long flags, int pc) | |
07edf712 | 1649 | { |
0d5c6e1c | 1650 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
51a763dd | 1651 | } |
0d5c6e1c | 1652 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1653 | |
2c4a33ab SRRH |
1654 | static struct ring_buffer *temp_buffer; |
1655 | ||
ccb469a1 SR |
1656 | struct ring_buffer_event * |
1657 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
1658 | struct ftrace_event_file *ftrace_file, | |
1659 | int type, unsigned long len, | |
1660 | unsigned long flags, int pc) | |
1661 | { | |
2c4a33ab SRRH |
1662 | struct ring_buffer_event *entry; |
1663 | ||
12883efb | 1664 | *current_rb = ftrace_file->tr->trace_buffer.buffer; |
2c4a33ab | 1665 | entry = trace_buffer_lock_reserve(*current_rb, |
ccb469a1 | 1666 | type, len, flags, pc); |
2c4a33ab SRRH |
1667 | /* |
1668 | * If tracing is off, but we have triggers enabled | |
1669 | * we still need to look at the event data. Use the temp_buffer | |
1670 | * to store the trace event for the tigger to use. It's recusive | |
1671 | * safe and will not be recorded anywhere. | |
1672 | */ | |
1673 | if (!entry && ftrace_file->flags & FTRACE_EVENT_FL_TRIGGER_COND) { | |
1674 | *current_rb = temp_buffer; | |
1675 | entry = trace_buffer_lock_reserve(*current_rb, | |
1676 | type, len, flags, pc); | |
1677 | } | |
1678 | return entry; | |
ccb469a1 SR |
1679 | } |
1680 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
1681 | ||
ef5580d0 | 1682 | struct ring_buffer_event * |
e77405ad SR |
1683 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1684 | int type, unsigned long len, | |
ef5580d0 SR |
1685 | unsigned long flags, int pc) |
1686 | { | |
12883efb | 1687 | *current_rb = global_trace.trace_buffer.buffer; |
e77405ad | 1688 | return trace_buffer_lock_reserve(*current_rb, |
ef5580d0 SR |
1689 | type, len, flags, pc); |
1690 | } | |
94487d6d | 1691 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1692 | |
e77405ad SR |
1693 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1694 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1695 | unsigned long flags, int pc) |
1696 | { | |
0d5c6e1c | 1697 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
07edf712 | 1698 | } |
94487d6d | 1699 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1700 | |
0d5c6e1c SR |
1701 | void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1702 | struct ring_buffer_event *event, | |
1703 | unsigned long flags, int pc, | |
1704 | struct pt_regs *regs) | |
1fd8df2c | 1705 | { |
7ffbd48d | 1706 | __buffer_unlock_commit(buffer, event); |
1fd8df2c MH |
1707 | |
1708 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1709 | ftrace_trace_userstack(buffer, flags, pc); | |
1710 | } | |
0d5c6e1c | 1711 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1712 | |
e77405ad SR |
1713 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1714 | struct ring_buffer_event *event) | |
77d9f465 | 1715 | { |
e77405ad | 1716 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1717 | } |
12acd473 | 1718 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1719 | |
e309b41d | 1720 | void |
7be42151 | 1721 | trace_function(struct trace_array *tr, |
38697053 SR |
1722 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1723 | int pc) | |
bc0c38d1 | 1724 | { |
e1112b4d | 1725 | struct ftrace_event_call *call = &event_function; |
12883efb | 1726 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 1727 | struct ring_buffer_event *event; |
777e208d | 1728 | struct ftrace_entry *entry; |
bc0c38d1 | 1729 | |
d769041f | 1730 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1731 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1732 | return; |
1733 | ||
e77405ad | 1734 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1735 | flags, pc); |
3928a8a2 SR |
1736 | if (!event) |
1737 | return; | |
1738 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1739 | entry->ip = ip; |
1740 | entry->parent_ip = parent_ip; | |
e1112b4d | 1741 | |
f306cc82 | 1742 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1743 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1744 | } |
1745 | ||
c0a0d0d3 | 1746 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1747 | |
1748 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1749 | struct ftrace_stack { | |
1750 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1751 | }; | |
1752 | ||
1753 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1754 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1755 | ||
e77405ad | 1756 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1757 | unsigned long flags, |
1fd8df2c | 1758 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1759 | { |
e1112b4d | 1760 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1761 | struct ring_buffer_event *event; |
777e208d | 1762 | struct stack_entry *entry; |
86387f7e | 1763 | struct stack_trace trace; |
4a9bd3f1 SR |
1764 | int use_stack; |
1765 | int size = FTRACE_STACK_ENTRIES; | |
1766 | ||
1767 | trace.nr_entries = 0; | |
1768 | trace.skip = skip; | |
1769 | ||
1770 | /* | |
1771 | * Since events can happen in NMIs there's no safe way to | |
1772 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1773 | * or NMI comes in, it will just have to use the default | |
1774 | * FTRACE_STACK_SIZE. | |
1775 | */ | |
1776 | preempt_disable_notrace(); | |
1777 | ||
82146529 | 1778 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
1779 | /* |
1780 | * We don't need any atomic variables, just a barrier. | |
1781 | * If an interrupt comes in, we don't care, because it would | |
1782 | * have exited and put the counter back to what we want. | |
1783 | * We just need a barrier to keep gcc from moving things | |
1784 | * around. | |
1785 | */ | |
1786 | barrier(); | |
1787 | if (use_stack == 1) { | |
bdffd893 | 1788 | trace.entries = this_cpu_ptr(ftrace_stack.calls); |
4a9bd3f1 SR |
1789 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; |
1790 | ||
1791 | if (regs) | |
1792 | save_stack_trace_regs(regs, &trace); | |
1793 | else | |
1794 | save_stack_trace(&trace); | |
1795 | ||
1796 | if (trace.nr_entries > size) | |
1797 | size = trace.nr_entries; | |
1798 | } else | |
1799 | /* From now on, use_stack is a boolean */ | |
1800 | use_stack = 0; | |
1801 | ||
1802 | size *= sizeof(unsigned long); | |
86387f7e | 1803 | |
e77405ad | 1804 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1805 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1806 | if (!event) |
4a9bd3f1 SR |
1807 | goto out; |
1808 | entry = ring_buffer_event_data(event); | |
86387f7e | 1809 | |
4a9bd3f1 SR |
1810 | memset(&entry->caller, 0, size); |
1811 | ||
1812 | if (use_stack) | |
1813 | memcpy(&entry->caller, trace.entries, | |
1814 | trace.nr_entries * sizeof(unsigned long)); | |
1815 | else { | |
1816 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1817 | trace.entries = entry->caller; | |
1818 | if (regs) | |
1819 | save_stack_trace_regs(regs, &trace); | |
1820 | else | |
1821 | save_stack_trace(&trace); | |
1822 | } | |
1823 | ||
1824 | entry->size = trace.nr_entries; | |
86387f7e | 1825 | |
f306cc82 | 1826 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1827 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1828 | |
1829 | out: | |
1830 | /* Again, don't let gcc optimize things here */ | |
1831 | barrier(); | |
82146529 | 1832 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
1833 | preempt_enable_notrace(); |
1834 | ||
f0a920d5 IM |
1835 | } |
1836 | ||
1fd8df2c MH |
1837 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1838 | int skip, int pc, struct pt_regs *regs) | |
1839 | { | |
1840 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1841 | return; | |
1842 | ||
1843 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1844 | } | |
1845 | ||
e77405ad SR |
1846 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1847 | int skip, int pc) | |
53614991 SR |
1848 | { |
1849 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1850 | return; | |
1851 | ||
1fd8df2c | 1852 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1853 | } |
1854 | ||
c0a0d0d3 FW |
1855 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1856 | int pc) | |
38697053 | 1857 | { |
12883efb | 1858 | __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); |
38697053 SR |
1859 | } |
1860 | ||
03889384 SR |
1861 | /** |
1862 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 1863 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 1864 | */ |
c142be8e | 1865 | void trace_dump_stack(int skip) |
03889384 SR |
1866 | { |
1867 | unsigned long flags; | |
1868 | ||
1869 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1870 | return; |
03889384 SR |
1871 | |
1872 | local_save_flags(flags); | |
1873 | ||
c142be8e SRRH |
1874 | /* |
1875 | * Skip 3 more, seems to get us at the caller of | |
1876 | * this function. | |
1877 | */ | |
1878 | skip += 3; | |
1879 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, | |
1880 | flags, skip, preempt_count(), NULL); | |
03889384 SR |
1881 | } |
1882 | ||
91e86e56 SR |
1883 | static DEFINE_PER_CPU(int, user_stack_count); |
1884 | ||
e77405ad SR |
1885 | void |
1886 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1887 | { |
e1112b4d | 1888 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1889 | struct ring_buffer_event *event; |
02b67518 TE |
1890 | struct userstack_entry *entry; |
1891 | struct stack_trace trace; | |
02b67518 TE |
1892 | |
1893 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1894 | return; | |
1895 | ||
b6345879 SR |
1896 | /* |
1897 | * NMIs can not handle page faults, even with fix ups. | |
1898 | * The save user stack can (and often does) fault. | |
1899 | */ | |
1900 | if (unlikely(in_nmi())) | |
1901 | return; | |
02b67518 | 1902 | |
91e86e56 SR |
1903 | /* |
1904 | * prevent recursion, since the user stack tracing may | |
1905 | * trigger other kernel events. | |
1906 | */ | |
1907 | preempt_disable(); | |
1908 | if (__this_cpu_read(user_stack_count)) | |
1909 | goto out; | |
1910 | ||
1911 | __this_cpu_inc(user_stack_count); | |
1912 | ||
e77405ad | 1913 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1914 | sizeof(*entry), flags, pc); |
02b67518 | 1915 | if (!event) |
1dbd1951 | 1916 | goto out_drop_count; |
02b67518 | 1917 | entry = ring_buffer_event_data(event); |
02b67518 | 1918 | |
48659d31 | 1919 | entry->tgid = current->tgid; |
02b67518 TE |
1920 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1921 | ||
1922 | trace.nr_entries = 0; | |
1923 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1924 | trace.skip = 0; | |
1925 | trace.entries = entry->caller; | |
1926 | ||
1927 | save_stack_trace_user(&trace); | |
f306cc82 | 1928 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1929 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1930 | |
1dbd1951 | 1931 | out_drop_count: |
91e86e56 | 1932 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1933 | out: |
1934 | preempt_enable(); | |
02b67518 TE |
1935 | } |
1936 | ||
4fd27358 HE |
1937 | #ifdef UNUSED |
1938 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1939 | { |
7be42151 | 1940 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1941 | } |
4fd27358 | 1942 | #endif /* UNUSED */ |
02b67518 | 1943 | |
c0a0d0d3 FW |
1944 | #endif /* CONFIG_STACKTRACE */ |
1945 | ||
07d777fe SR |
1946 | /* created for use with alloc_percpu */ |
1947 | struct trace_buffer_struct { | |
1948 | char buffer[TRACE_BUF_SIZE]; | |
1949 | }; | |
1950 | ||
1951 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1952 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1953 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1954 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1955 | ||
1956 | /* | |
1957 | * The buffer used is dependent on the context. There is a per cpu | |
1958 | * buffer for normal context, softirq contex, hard irq context and | |
1959 | * for NMI context. Thise allows for lockless recording. | |
1960 | * | |
1961 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1962 | */ | |
1963 | static char *get_trace_buf(void) | |
1964 | { | |
1965 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
1966 | |
1967 | /* | |
1968 | * If we have allocated per cpu buffers, then we do not | |
1969 | * need to do any locking. | |
1970 | */ | |
1971 | if (in_nmi()) | |
1972 | percpu_buffer = trace_percpu_nmi_buffer; | |
1973 | else if (in_irq()) | |
1974 | percpu_buffer = trace_percpu_irq_buffer; | |
1975 | else if (in_softirq()) | |
1976 | percpu_buffer = trace_percpu_sirq_buffer; | |
1977 | else | |
1978 | percpu_buffer = trace_percpu_buffer; | |
1979 | ||
1980 | if (!percpu_buffer) | |
1981 | return NULL; | |
1982 | ||
d8a0349c | 1983 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
1984 | } |
1985 | ||
1986 | static int alloc_percpu_trace_buffer(void) | |
1987 | { | |
1988 | struct trace_buffer_struct *buffers; | |
1989 | struct trace_buffer_struct *sirq_buffers; | |
1990 | struct trace_buffer_struct *irq_buffers; | |
1991 | struct trace_buffer_struct *nmi_buffers; | |
1992 | ||
1993 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1994 | if (!buffers) | |
1995 | goto err_warn; | |
1996 | ||
1997 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1998 | if (!sirq_buffers) | |
1999 | goto err_sirq; | |
2000 | ||
2001 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
2002 | if (!irq_buffers) | |
2003 | goto err_irq; | |
2004 | ||
2005 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
2006 | if (!nmi_buffers) | |
2007 | goto err_nmi; | |
2008 | ||
2009 | trace_percpu_buffer = buffers; | |
2010 | trace_percpu_sirq_buffer = sirq_buffers; | |
2011 | trace_percpu_irq_buffer = irq_buffers; | |
2012 | trace_percpu_nmi_buffer = nmi_buffers; | |
2013 | ||
2014 | return 0; | |
2015 | ||
2016 | err_nmi: | |
2017 | free_percpu(irq_buffers); | |
2018 | err_irq: | |
2019 | free_percpu(sirq_buffers); | |
2020 | err_sirq: | |
2021 | free_percpu(buffers); | |
2022 | err_warn: | |
2023 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
2024 | return -ENOMEM; | |
2025 | } | |
2026 | ||
81698831 SR |
2027 | static int buffers_allocated; |
2028 | ||
07d777fe SR |
2029 | void trace_printk_init_buffers(void) |
2030 | { | |
07d777fe SR |
2031 | if (buffers_allocated) |
2032 | return; | |
2033 | ||
2034 | if (alloc_percpu_trace_buffer()) | |
2035 | return; | |
2036 | ||
2184db46 SR |
2037 | /* trace_printk() is for debug use only. Don't use it in production. */ |
2038 | ||
69a1c994 BP |
2039 | pr_warning("\n"); |
2040 | pr_warning("**********************************************************\n"); | |
2184db46 SR |
2041 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); |
2042 | pr_warning("** **\n"); | |
2043 | pr_warning("** trace_printk() being used. Allocating extra memory. **\n"); | |
2044 | pr_warning("** **\n"); | |
2045 | pr_warning("** This means that this is a DEBUG kernel and it is **\n"); | |
eff264ef | 2046 | pr_warning("** unsafe for production use. **\n"); |
2184db46 SR |
2047 | pr_warning("** **\n"); |
2048 | pr_warning("** If you see this message and you are not debugging **\n"); | |
2049 | pr_warning("** the kernel, report this immediately to your vendor! **\n"); | |
2050 | pr_warning("** **\n"); | |
2051 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
2052 | pr_warning("**********************************************************\n"); | |
07d777fe | 2053 | |
b382ede6 SR |
2054 | /* Expand the buffers to set size */ |
2055 | tracing_update_buffers(); | |
2056 | ||
07d777fe | 2057 | buffers_allocated = 1; |
81698831 SR |
2058 | |
2059 | /* | |
2060 | * trace_printk_init_buffers() can be called by modules. | |
2061 | * If that happens, then we need to start cmdline recording | |
2062 | * directly here. If the global_trace.buffer is already | |
2063 | * allocated here, then this was called by module code. | |
2064 | */ | |
12883efb | 2065 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
2066 | tracing_start_cmdline_record(); |
2067 | } | |
2068 | ||
2069 | void trace_printk_start_comm(void) | |
2070 | { | |
2071 | /* Start tracing comms if trace printk is set */ | |
2072 | if (!buffers_allocated) | |
2073 | return; | |
2074 | tracing_start_cmdline_record(); | |
2075 | } | |
2076 | ||
2077 | static void trace_printk_start_stop_comm(int enabled) | |
2078 | { | |
2079 | if (!buffers_allocated) | |
2080 | return; | |
2081 | ||
2082 | if (enabled) | |
2083 | tracing_start_cmdline_record(); | |
2084 | else | |
2085 | tracing_stop_cmdline_record(); | |
07d777fe SR |
2086 | } |
2087 | ||
769b0441 | 2088 | /** |
48ead020 | 2089 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
2090 | * |
2091 | */ | |
40ce74f1 | 2092 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 2093 | { |
e1112b4d | 2094 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 2095 | struct ring_buffer_event *event; |
e77405ad | 2096 | struct ring_buffer *buffer; |
769b0441 | 2097 | struct trace_array *tr = &global_trace; |
48ead020 | 2098 | struct bprint_entry *entry; |
769b0441 | 2099 | unsigned long flags; |
07d777fe SR |
2100 | char *tbuffer; |
2101 | int len = 0, size, pc; | |
769b0441 FW |
2102 | |
2103 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
2104 | return 0; | |
2105 | ||
2106 | /* Don't pollute graph traces with trace_vprintk internals */ | |
2107 | pause_graph_tracing(); | |
2108 | ||
2109 | pc = preempt_count(); | |
5168ae50 | 2110 | preempt_disable_notrace(); |
769b0441 | 2111 | |
07d777fe SR |
2112 | tbuffer = get_trace_buf(); |
2113 | if (!tbuffer) { | |
2114 | len = 0; | |
769b0441 | 2115 | goto out; |
07d777fe | 2116 | } |
769b0441 | 2117 | |
07d777fe | 2118 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 2119 | |
07d777fe SR |
2120 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
2121 | goto out; | |
769b0441 | 2122 | |
07d777fe | 2123 | local_save_flags(flags); |
769b0441 | 2124 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 2125 | buffer = tr->trace_buffer.buffer; |
e77405ad SR |
2126 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
2127 | flags, pc); | |
769b0441 | 2128 | if (!event) |
07d777fe | 2129 | goto out; |
769b0441 FW |
2130 | entry = ring_buffer_event_data(event); |
2131 | entry->ip = ip; | |
769b0441 FW |
2132 | entry->fmt = fmt; |
2133 | ||
07d777fe | 2134 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
f306cc82 | 2135 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2136 | __buffer_unlock_commit(buffer, event); |
d931369b SR |
2137 | ftrace_trace_stack(buffer, flags, 6, pc); |
2138 | } | |
769b0441 | 2139 | |
769b0441 | 2140 | out: |
5168ae50 | 2141 | preempt_enable_notrace(); |
769b0441 FW |
2142 | unpause_graph_tracing(); |
2143 | ||
2144 | return len; | |
2145 | } | |
48ead020 FW |
2146 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
2147 | ||
12883efb SRRH |
2148 | static int |
2149 | __trace_array_vprintk(struct ring_buffer *buffer, | |
2150 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 2151 | { |
e1112b4d | 2152 | struct ftrace_event_call *call = &event_print; |
48ead020 | 2153 | struct ring_buffer_event *event; |
07d777fe | 2154 | int len = 0, size, pc; |
48ead020 | 2155 | struct print_entry *entry; |
07d777fe SR |
2156 | unsigned long flags; |
2157 | char *tbuffer; | |
48ead020 FW |
2158 | |
2159 | if (tracing_disabled || tracing_selftest_running) | |
2160 | return 0; | |
2161 | ||
07d777fe SR |
2162 | /* Don't pollute graph traces with trace_vprintk internals */ |
2163 | pause_graph_tracing(); | |
2164 | ||
48ead020 FW |
2165 | pc = preempt_count(); |
2166 | preempt_disable_notrace(); | |
48ead020 | 2167 | |
07d777fe SR |
2168 | |
2169 | tbuffer = get_trace_buf(); | |
2170 | if (!tbuffer) { | |
2171 | len = 0; | |
48ead020 | 2172 | goto out; |
07d777fe | 2173 | } |
48ead020 | 2174 | |
3558a5ac | 2175 | len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
48ead020 | 2176 | |
07d777fe | 2177 | local_save_flags(flags); |
48ead020 | 2178 | size = sizeof(*entry) + len + 1; |
e77405ad | 2179 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
07d777fe | 2180 | flags, pc); |
48ead020 | 2181 | if (!event) |
07d777fe | 2182 | goto out; |
48ead020 | 2183 | entry = ring_buffer_event_data(event); |
c13d2f7c | 2184 | entry->ip = ip; |
48ead020 | 2185 | |
3558a5ac | 2186 | memcpy(&entry->buf, tbuffer, len + 1); |
f306cc82 | 2187 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2188 | __buffer_unlock_commit(buffer, event); |
07d777fe | 2189 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 2190 | } |
48ead020 FW |
2191 | out: |
2192 | preempt_enable_notrace(); | |
07d777fe | 2193 | unpause_graph_tracing(); |
48ead020 FW |
2194 | |
2195 | return len; | |
2196 | } | |
659372d3 | 2197 | |
12883efb SRRH |
2198 | int trace_array_vprintk(struct trace_array *tr, |
2199 | unsigned long ip, const char *fmt, va_list args) | |
2200 | { | |
2201 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
2202 | } | |
2203 | ||
2204 | int trace_array_printk(struct trace_array *tr, | |
2205 | unsigned long ip, const char *fmt, ...) | |
2206 | { | |
2207 | int ret; | |
2208 | va_list ap; | |
2209 | ||
2210 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2211 | return 0; | |
2212 | ||
2213 | va_start(ap, fmt); | |
2214 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
2215 | va_end(ap); | |
2216 | return ret; | |
2217 | } | |
2218 | ||
2219 | int trace_array_printk_buf(struct ring_buffer *buffer, | |
2220 | unsigned long ip, const char *fmt, ...) | |
2221 | { | |
2222 | int ret; | |
2223 | va_list ap; | |
2224 | ||
2225 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2226 | return 0; | |
2227 | ||
2228 | va_start(ap, fmt); | |
2229 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
2230 | va_end(ap); | |
2231 | return ret; | |
2232 | } | |
2233 | ||
659372d3 SR |
2234 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
2235 | { | |
a813a159 | 2236 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 2237 | } |
769b0441 FW |
2238 | EXPORT_SYMBOL_GPL(trace_vprintk); |
2239 | ||
e2ac8ef5 | 2240 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 2241 | { |
6d158a81 SR |
2242 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
2243 | ||
5a90f577 | 2244 | iter->idx++; |
6d158a81 SR |
2245 | if (buf_iter) |
2246 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
2247 | } |
2248 | ||
e309b41d | 2249 | static struct trace_entry * |
bc21b478 SR |
2250 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
2251 | unsigned long *lost_events) | |
dd0e545f | 2252 | { |
3928a8a2 | 2253 | struct ring_buffer_event *event; |
6d158a81 | 2254 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 2255 | |
d769041f SR |
2256 | if (buf_iter) |
2257 | event = ring_buffer_iter_peek(buf_iter, ts); | |
2258 | else | |
12883efb | 2259 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 2260 | lost_events); |
d769041f | 2261 | |
4a9bd3f1 SR |
2262 | if (event) { |
2263 | iter->ent_size = ring_buffer_event_length(event); | |
2264 | return ring_buffer_event_data(event); | |
2265 | } | |
2266 | iter->ent_size = 0; | |
2267 | return NULL; | |
dd0e545f | 2268 | } |
d769041f | 2269 | |
dd0e545f | 2270 | static struct trace_entry * |
bc21b478 SR |
2271 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
2272 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 2273 | { |
12883efb | 2274 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 2275 | struct trace_entry *ent, *next = NULL; |
aa27497c | 2276 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 2277 | int cpu_file = iter->cpu_file; |
3928a8a2 | 2278 | u64 next_ts = 0, ts; |
bc0c38d1 | 2279 | int next_cpu = -1; |
12b5da34 | 2280 | int next_size = 0; |
bc0c38d1 SR |
2281 | int cpu; |
2282 | ||
b04cc6b1 FW |
2283 | /* |
2284 | * If we are in a per_cpu trace file, don't bother by iterating over | |
2285 | * all cpu and peek directly. | |
2286 | */ | |
ae3b5093 | 2287 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
2288 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
2289 | return NULL; | |
bc21b478 | 2290 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
2291 | if (ent_cpu) |
2292 | *ent_cpu = cpu_file; | |
2293 | ||
2294 | return ent; | |
2295 | } | |
2296 | ||
ab46428c | 2297 | for_each_tracing_cpu(cpu) { |
dd0e545f | 2298 | |
3928a8a2 SR |
2299 | if (ring_buffer_empty_cpu(buffer, cpu)) |
2300 | continue; | |
dd0e545f | 2301 | |
bc21b478 | 2302 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 2303 | |
cdd31cd2 IM |
2304 | /* |
2305 | * Pick the entry with the smallest timestamp: | |
2306 | */ | |
3928a8a2 | 2307 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
2308 | next = ent; |
2309 | next_cpu = cpu; | |
3928a8a2 | 2310 | next_ts = ts; |
bc21b478 | 2311 | next_lost = lost_events; |
12b5da34 | 2312 | next_size = iter->ent_size; |
bc0c38d1 SR |
2313 | } |
2314 | } | |
2315 | ||
12b5da34 SR |
2316 | iter->ent_size = next_size; |
2317 | ||
bc0c38d1 SR |
2318 | if (ent_cpu) |
2319 | *ent_cpu = next_cpu; | |
2320 | ||
3928a8a2 SR |
2321 | if (ent_ts) |
2322 | *ent_ts = next_ts; | |
2323 | ||
bc21b478 SR |
2324 | if (missing_events) |
2325 | *missing_events = next_lost; | |
2326 | ||
bc0c38d1 SR |
2327 | return next; |
2328 | } | |
2329 | ||
dd0e545f | 2330 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
2331 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
2332 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 2333 | { |
bc21b478 | 2334 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
2335 | } |
2336 | ||
2337 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 2338 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 2339 | { |
bc21b478 SR |
2340 | iter->ent = __find_next_entry(iter, &iter->cpu, |
2341 | &iter->lost_events, &iter->ts); | |
dd0e545f | 2342 | |
3928a8a2 | 2343 | if (iter->ent) |
e2ac8ef5 | 2344 | trace_iterator_increment(iter); |
dd0e545f | 2345 | |
3928a8a2 | 2346 | return iter->ent ? iter : NULL; |
b3806b43 | 2347 | } |
bc0c38d1 | 2348 | |
e309b41d | 2349 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 2350 | { |
12883efb | 2351 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 2352 | &iter->lost_events); |
bc0c38d1 SR |
2353 | } |
2354 | ||
e309b41d | 2355 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
2356 | { |
2357 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 2358 | int i = (int)*pos; |
4e3c3333 | 2359 | void *ent; |
bc0c38d1 | 2360 | |
a63ce5b3 SR |
2361 | WARN_ON_ONCE(iter->leftover); |
2362 | ||
bc0c38d1 SR |
2363 | (*pos)++; |
2364 | ||
2365 | /* can't go backwards */ | |
2366 | if (iter->idx > i) | |
2367 | return NULL; | |
2368 | ||
2369 | if (iter->idx < 0) | |
955b61e5 | 2370 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2371 | else |
2372 | ent = iter; | |
2373 | ||
2374 | while (ent && iter->idx < i) | |
955b61e5 | 2375 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2376 | |
2377 | iter->pos = *pos; | |
2378 | ||
bc0c38d1 SR |
2379 | return ent; |
2380 | } | |
2381 | ||
955b61e5 | 2382 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 2383 | { |
2f26ebd5 SR |
2384 | struct ring_buffer_event *event; |
2385 | struct ring_buffer_iter *buf_iter; | |
2386 | unsigned long entries = 0; | |
2387 | u64 ts; | |
2388 | ||
12883efb | 2389 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 2390 | |
6d158a81 SR |
2391 | buf_iter = trace_buffer_iter(iter, cpu); |
2392 | if (!buf_iter) | |
2f26ebd5 SR |
2393 | return; |
2394 | ||
2f26ebd5 SR |
2395 | ring_buffer_iter_reset(buf_iter); |
2396 | ||
2397 | /* | |
2398 | * We could have the case with the max latency tracers | |
2399 | * that a reset never took place on a cpu. This is evident | |
2400 | * by the timestamp being before the start of the buffer. | |
2401 | */ | |
2402 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 2403 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
2404 | break; |
2405 | entries++; | |
2406 | ring_buffer_read(buf_iter, NULL); | |
2407 | } | |
2408 | ||
12883efb | 2409 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2410 | } |
2411 | ||
d7350c3f | 2412 | /* |
d7350c3f FW |
2413 | * The current tracer is copied to avoid a global locking |
2414 | * all around. | |
2415 | */ | |
bc0c38d1 SR |
2416 | static void *s_start(struct seq_file *m, loff_t *pos) |
2417 | { | |
2418 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2419 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2420 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2421 | void *p = NULL; |
2422 | loff_t l = 0; | |
3928a8a2 | 2423 | int cpu; |
bc0c38d1 | 2424 | |
2fd196ec HT |
2425 | /* |
2426 | * copy the tracer to avoid using a global lock all around. | |
2427 | * iter->trace is a copy of current_trace, the pointer to the | |
2428 | * name may be used instead of a strcmp(), as iter->trace->name | |
2429 | * will point to the same string as current_trace->name. | |
2430 | */ | |
bc0c38d1 | 2431 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2432 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2433 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2434 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2435 | |
12883efb | 2436 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2437 | if (iter->snapshot && iter->trace->use_max_tr) |
2438 | return ERR_PTR(-EBUSY); | |
12883efb | 2439 | #endif |
debdd57f HT |
2440 | |
2441 | if (!iter->snapshot) | |
2442 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2443 | |
bc0c38d1 SR |
2444 | if (*pos != iter->pos) { |
2445 | iter->ent = NULL; | |
2446 | iter->cpu = 0; | |
2447 | iter->idx = -1; | |
2448 | ||
ae3b5093 | 2449 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2450 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2451 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2452 | } else |
2f26ebd5 | 2453 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2454 | |
ac91d854 | 2455 | iter->leftover = 0; |
bc0c38d1 SR |
2456 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2457 | ; | |
2458 | ||
2459 | } else { | |
a63ce5b3 SR |
2460 | /* |
2461 | * If we overflowed the seq_file before, then we want | |
2462 | * to just reuse the trace_seq buffer again. | |
2463 | */ | |
2464 | if (iter->leftover) | |
2465 | p = iter; | |
2466 | else { | |
2467 | l = *pos - 1; | |
2468 | p = s_next(m, p, &l); | |
2469 | } | |
bc0c38d1 SR |
2470 | } |
2471 | ||
4f535968 | 2472 | trace_event_read_lock(); |
7e53bd42 | 2473 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2474 | return p; |
2475 | } | |
2476 | ||
2477 | static void s_stop(struct seq_file *m, void *p) | |
2478 | { | |
7e53bd42 LJ |
2479 | struct trace_iterator *iter = m->private; |
2480 | ||
12883efb | 2481 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2482 | if (iter->snapshot && iter->trace->use_max_tr) |
2483 | return; | |
12883efb | 2484 | #endif |
debdd57f HT |
2485 | |
2486 | if (!iter->snapshot) | |
2487 | atomic_dec(&trace_record_cmdline_disabled); | |
12883efb | 2488 | |
7e53bd42 | 2489 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2490 | trace_event_read_unlock(); |
bc0c38d1 SR |
2491 | } |
2492 | ||
39eaf7ef | 2493 | static void |
12883efb SRRH |
2494 | get_total_entries(struct trace_buffer *buf, |
2495 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
2496 | { |
2497 | unsigned long count; | |
2498 | int cpu; | |
2499 | ||
2500 | *total = 0; | |
2501 | *entries = 0; | |
2502 | ||
2503 | for_each_tracing_cpu(cpu) { | |
12883efb | 2504 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2505 | /* |
2506 | * If this buffer has skipped entries, then we hold all | |
2507 | * entries for the trace and we need to ignore the | |
2508 | * ones before the time stamp. | |
2509 | */ | |
12883efb SRRH |
2510 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
2511 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2512 | /* total is the same as the entries */ |
2513 | *total += count; | |
2514 | } else | |
2515 | *total += count + | |
12883efb | 2516 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2517 | *entries += count; |
2518 | } | |
2519 | } | |
2520 | ||
e309b41d | 2521 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2522 | { |
d79ac28f RV |
2523 | seq_puts(m, "# _------=> CPU# \n" |
2524 | "# / _-----=> irqs-off \n" | |
2525 | "# | / _----=> need-resched \n" | |
2526 | "# || / _---=> hardirq/softirq \n" | |
2527 | "# ||| / _--=> preempt-depth \n" | |
2528 | "# |||| / delay \n" | |
2529 | "# cmd pid ||||| time | caller \n" | |
2530 | "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2531 | } |
2532 | ||
12883efb | 2533 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 2534 | { |
39eaf7ef SR |
2535 | unsigned long total; |
2536 | unsigned long entries; | |
2537 | ||
12883efb | 2538 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
2539 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
2540 | entries, total, num_online_cpus()); | |
2541 | seq_puts(m, "#\n"); | |
2542 | } | |
2543 | ||
12883efb | 2544 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) |
39eaf7ef | 2545 | { |
12883efb | 2546 | print_event_info(buf, m); |
d79ac28f RV |
2547 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n" |
2548 | "# | | | | |\n"); | |
bc0c38d1 SR |
2549 | } |
2550 | ||
12883efb | 2551 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) |
77271ce4 | 2552 | { |
12883efb | 2553 | print_event_info(buf, m); |
d79ac28f RV |
2554 | seq_puts(m, "# _-----=> irqs-off\n" |
2555 | "# / _----=> need-resched\n" | |
2556 | "# | / _---=> hardirq/softirq\n" | |
2557 | "# || / _--=> preempt-depth\n" | |
2558 | "# ||| / delay\n" | |
2559 | "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n" | |
2560 | "# | | | |||| | |\n"); | |
77271ce4 | 2561 | } |
bc0c38d1 | 2562 | |
62b915f1 | 2563 | void |
bc0c38d1 SR |
2564 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2565 | { | |
2566 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
12883efb SRRH |
2567 | struct trace_buffer *buf = iter->trace_buffer; |
2568 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 2569 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2570 | unsigned long entries; |
2571 | unsigned long total; | |
bc0c38d1 SR |
2572 | const char *name = "preemption"; |
2573 | ||
d840f718 | 2574 | name = type->name; |
bc0c38d1 | 2575 | |
12883efb | 2576 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 2577 | |
888b55dc | 2578 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2579 | name, UTS_RELEASE); |
888b55dc | 2580 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2581 | "---------------------------------\n"); |
888b55dc | 2582 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2583 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2584 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2585 | entries, |
4c11d7ae | 2586 | total, |
12883efb | 2587 | buf->cpu, |
bc0c38d1 SR |
2588 | #if defined(CONFIG_PREEMPT_NONE) |
2589 | "server", | |
2590 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2591 | "desktop", | |
b5c21b45 | 2592 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2593 | "preempt", |
2594 | #else | |
2595 | "unknown", | |
2596 | #endif | |
2597 | /* These are reserved for later use */ | |
2598 | 0, 0, 0, 0); | |
2599 | #ifdef CONFIG_SMP | |
2600 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2601 | #else | |
2602 | seq_puts(m, ")\n"); | |
2603 | #endif | |
888b55dc KM |
2604 | seq_puts(m, "# -----------------\n"); |
2605 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2606 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2607 | data->comm, data->pid, |
2608 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2609 | data->policy, data->rt_priority); |
888b55dc | 2610 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2611 | |
2612 | if (data->critical_start) { | |
888b55dc | 2613 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2614 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2615 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2616 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2617 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2618 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2619 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2620 | } |
2621 | ||
888b55dc | 2622 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2623 | } |
2624 | ||
a309720c SR |
2625 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2626 | { | |
2627 | struct trace_seq *s = &iter->seq; | |
2628 | ||
12ef7d44 SR |
2629 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2630 | return; | |
2631 | ||
2632 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2633 | return; | |
2634 | ||
4462344e | 2635 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2636 | return; |
2637 | ||
12883efb | 2638 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
2639 | return; |
2640 | ||
4462344e | 2641 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2642 | |
2643 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2644 | if (iter->idx > 1) | |
2645 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2646 | iter->cpu); | |
a309720c SR |
2647 | } |
2648 | ||
2c4f035f | 2649 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2650 | { |
214023c3 | 2651 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2652 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2653 | struct trace_entry *entry; |
f633cef0 | 2654 | struct trace_event *event; |
bc0c38d1 | 2655 | |
4e3c3333 | 2656 | entry = iter->ent; |
dd0e545f | 2657 | |
a309720c SR |
2658 | test_cpu_buff_start(iter); |
2659 | ||
c4a8e8be | 2660 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2661 | |
c4a8e8be | 2662 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
2663 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) |
2664 | trace_print_lat_context(iter); | |
2665 | else | |
2666 | trace_print_context(iter); | |
c4a8e8be | 2667 | } |
bc0c38d1 | 2668 | |
19a7fe20 SRRH |
2669 | if (trace_seq_has_overflowed(s)) |
2670 | return TRACE_TYPE_PARTIAL_LINE; | |
2671 | ||
268ccda0 | 2672 | if (event) |
a9a57763 | 2673 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 | 2674 | |
19a7fe20 | 2675 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
02b67518 | 2676 | |
19a7fe20 | 2677 | return trace_handle_return(s); |
bc0c38d1 SR |
2678 | } |
2679 | ||
2c4f035f | 2680 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2681 | { |
2682 | struct trace_seq *s = &iter->seq; | |
2683 | struct trace_entry *entry; | |
f633cef0 | 2684 | struct trace_event *event; |
f9896bf3 IM |
2685 | |
2686 | entry = iter->ent; | |
dd0e545f | 2687 | |
19a7fe20 SRRH |
2688 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) |
2689 | trace_seq_printf(s, "%d %d %llu ", | |
2690 | entry->pid, iter->cpu, iter->ts); | |
2691 | ||
2692 | if (trace_seq_has_overflowed(s)) | |
2693 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 | 2694 | |
f633cef0 | 2695 | event = ftrace_find_event(entry->type); |
268ccda0 | 2696 | if (event) |
a9a57763 | 2697 | return event->funcs->raw(iter, 0, event); |
d9793bd8 | 2698 | |
19a7fe20 | 2699 | trace_seq_printf(s, "%d ?\n", entry->type); |
777e208d | 2700 | |
19a7fe20 | 2701 | return trace_handle_return(s); |
f9896bf3 IM |
2702 | } |
2703 | ||
2c4f035f | 2704 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2705 | { |
2706 | struct trace_seq *s = &iter->seq; | |
2707 | unsigned char newline = '\n'; | |
2708 | struct trace_entry *entry; | |
f633cef0 | 2709 | struct trace_event *event; |
5e3ca0ec IM |
2710 | |
2711 | entry = iter->ent; | |
dd0e545f | 2712 | |
c4a8e8be | 2713 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
2714 | SEQ_PUT_HEX_FIELD(s, entry->pid); |
2715 | SEQ_PUT_HEX_FIELD(s, iter->cpu); | |
2716 | SEQ_PUT_HEX_FIELD(s, iter->ts); | |
2717 | if (trace_seq_has_overflowed(s)) | |
2718 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 2719 | } |
5e3ca0ec | 2720 | |
f633cef0 | 2721 | event = ftrace_find_event(entry->type); |
268ccda0 | 2722 | if (event) { |
a9a57763 | 2723 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2724 | if (ret != TRACE_TYPE_HANDLED) |
2725 | return ret; | |
2726 | } | |
7104f300 | 2727 | |
19a7fe20 | 2728 | SEQ_PUT_FIELD(s, newline); |
5e3ca0ec | 2729 | |
19a7fe20 | 2730 | return trace_handle_return(s); |
5e3ca0ec IM |
2731 | } |
2732 | ||
2c4f035f | 2733 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2734 | { |
2735 | struct trace_seq *s = &iter->seq; | |
2736 | struct trace_entry *entry; | |
f633cef0 | 2737 | struct trace_event *event; |
cb0f12aa IM |
2738 | |
2739 | entry = iter->ent; | |
dd0e545f | 2740 | |
c4a8e8be | 2741 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
2742 | SEQ_PUT_FIELD(s, entry->pid); |
2743 | SEQ_PUT_FIELD(s, iter->cpu); | |
2744 | SEQ_PUT_FIELD(s, iter->ts); | |
2745 | if (trace_seq_has_overflowed(s)) | |
2746 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 2747 | } |
cb0f12aa | 2748 | |
f633cef0 | 2749 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2750 | return event ? event->funcs->binary(iter, 0, event) : |
2751 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2752 | } |
2753 | ||
62b915f1 | 2754 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2755 | { |
6d158a81 | 2756 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2757 | int cpu; |
2758 | ||
9aba60fe | 2759 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 2760 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 2761 | cpu = iter->cpu_file; |
6d158a81 SR |
2762 | buf_iter = trace_buffer_iter(iter, cpu); |
2763 | if (buf_iter) { | |
2764 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2765 | return 0; |
2766 | } else { | |
12883efb | 2767 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
2768 | return 0; |
2769 | } | |
2770 | return 1; | |
2771 | } | |
2772 | ||
ab46428c | 2773 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2774 | buf_iter = trace_buffer_iter(iter, cpu); |
2775 | if (buf_iter) { | |
2776 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2777 | return 0; |
2778 | } else { | |
12883efb | 2779 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
2780 | return 0; |
2781 | } | |
bc0c38d1 | 2782 | } |
d769041f | 2783 | |
797d3712 | 2784 | return 1; |
bc0c38d1 SR |
2785 | } |
2786 | ||
4f535968 | 2787 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2788 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2789 | { |
2c4f035f FW |
2790 | enum print_line_t ret; |
2791 | ||
19a7fe20 SRRH |
2792 | if (iter->lost_events) { |
2793 | trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2794 | iter->cpu, iter->lost_events); | |
2795 | if (trace_seq_has_overflowed(&iter->seq)) | |
2796 | return TRACE_TYPE_PARTIAL_LINE; | |
2797 | } | |
bc21b478 | 2798 | |
2c4f035f FW |
2799 | if (iter->trace && iter->trace->print_line) { |
2800 | ret = iter->trace->print_line(iter); | |
2801 | if (ret != TRACE_TYPE_UNHANDLED) | |
2802 | return ret; | |
2803 | } | |
72829bc3 | 2804 | |
09ae7234 SRRH |
2805 | if (iter->ent->type == TRACE_BPUTS && |
2806 | trace_flags & TRACE_ITER_PRINTK && | |
2807 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
2808 | return trace_print_bputs_msg_only(iter); | |
2809 | ||
48ead020 FW |
2810 | if (iter->ent->type == TRACE_BPRINT && |
2811 | trace_flags & TRACE_ITER_PRINTK && | |
2812 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2813 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2814 | |
66896a85 FW |
2815 | if (iter->ent->type == TRACE_PRINT && |
2816 | trace_flags & TRACE_ITER_PRINTK && | |
2817 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2818 | return trace_print_printk_msg_only(iter); |
66896a85 | 2819 | |
cb0f12aa IM |
2820 | if (trace_flags & TRACE_ITER_BIN) |
2821 | return print_bin_fmt(iter); | |
2822 | ||
5e3ca0ec IM |
2823 | if (trace_flags & TRACE_ITER_HEX) |
2824 | return print_hex_fmt(iter); | |
2825 | ||
f9896bf3 IM |
2826 | if (trace_flags & TRACE_ITER_RAW) |
2827 | return print_raw_fmt(iter); | |
2828 | ||
f9896bf3 IM |
2829 | return print_trace_fmt(iter); |
2830 | } | |
2831 | ||
7e9a49ef JO |
2832 | void trace_latency_header(struct seq_file *m) |
2833 | { | |
2834 | struct trace_iterator *iter = m->private; | |
2835 | ||
2836 | /* print nothing if the buffers are empty */ | |
2837 | if (trace_empty(iter)) | |
2838 | return; | |
2839 | ||
2840 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2841 | print_trace_header(m, iter); | |
2842 | ||
2843 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2844 | print_lat_help_header(m); | |
2845 | } | |
2846 | ||
62b915f1 JO |
2847 | void trace_default_header(struct seq_file *m) |
2848 | { | |
2849 | struct trace_iterator *iter = m->private; | |
2850 | ||
f56e7f8e JO |
2851 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2852 | return; | |
2853 | ||
62b915f1 JO |
2854 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2855 | /* print nothing if the buffers are empty */ | |
2856 | if (trace_empty(iter)) | |
2857 | return; | |
2858 | print_trace_header(m, iter); | |
2859 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2860 | print_lat_help_header(m); | |
2861 | } else { | |
77271ce4 SR |
2862 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2863 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
12883efb | 2864 | print_func_help_header_irq(iter->trace_buffer, m); |
77271ce4 | 2865 | else |
12883efb | 2866 | print_func_help_header(iter->trace_buffer, m); |
77271ce4 | 2867 | } |
62b915f1 JO |
2868 | } |
2869 | } | |
2870 | ||
e0a413f6 SR |
2871 | static void test_ftrace_alive(struct seq_file *m) |
2872 | { | |
2873 | if (!ftrace_is_dead()) | |
2874 | return; | |
d79ac28f RV |
2875 | seq_puts(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n" |
2876 | "# MAY BE MISSING FUNCTION EVENTS\n"); | |
e0a413f6 SR |
2877 | } |
2878 | ||
d8741e2e | 2879 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 2880 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 2881 | { |
d79ac28f RV |
2882 | seq_puts(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n" |
2883 | "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" | |
2884 | "# Takes a snapshot of the main buffer.\n" | |
2885 | "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n" | |
2886 | "# (Doesn't have to be '2' works with any number that\n" | |
2887 | "# is not a '0' or '1')\n"); | |
d8741e2e | 2888 | } |
f1affcaa SRRH |
2889 | |
2890 | static void show_snapshot_percpu_help(struct seq_file *m) | |
2891 | { | |
fa6f0cc7 | 2892 | seq_puts(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); |
f1affcaa | 2893 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP |
d79ac28f RV |
2894 | seq_puts(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" |
2895 | "# Takes a snapshot of the main buffer for this cpu.\n"); | |
f1affcaa | 2896 | #else |
d79ac28f RV |
2897 | seq_puts(m, "# echo 1 > snapshot : Not supported with this kernel.\n" |
2898 | "# Must use main snapshot file to allocate.\n"); | |
f1affcaa | 2899 | #endif |
d79ac28f RV |
2900 | seq_puts(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n" |
2901 | "# (Doesn't have to be '2' works with any number that\n" | |
2902 | "# is not a '0' or '1')\n"); | |
f1affcaa SRRH |
2903 | } |
2904 | ||
d8741e2e SRRH |
2905 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
2906 | { | |
45ad21ca | 2907 | if (iter->tr->allocated_snapshot) |
fa6f0cc7 | 2908 | seq_puts(m, "#\n# * Snapshot is allocated *\n#\n"); |
d8741e2e | 2909 | else |
fa6f0cc7 | 2910 | seq_puts(m, "#\n# * Snapshot is freed *\n#\n"); |
d8741e2e | 2911 | |
fa6f0cc7 | 2912 | seq_puts(m, "# Snapshot commands:\n"); |
f1affcaa SRRH |
2913 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
2914 | show_snapshot_main_help(m); | |
2915 | else | |
2916 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
2917 | } |
2918 | #else | |
2919 | /* Should never be called */ | |
2920 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
2921 | #endif | |
2922 | ||
bc0c38d1 SR |
2923 | static int s_show(struct seq_file *m, void *v) |
2924 | { | |
2925 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2926 | int ret; |
bc0c38d1 SR |
2927 | |
2928 | if (iter->ent == NULL) { | |
2929 | if (iter->tr) { | |
2930 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2931 | seq_puts(m, "#\n"); | |
e0a413f6 | 2932 | test_ftrace_alive(m); |
bc0c38d1 | 2933 | } |
d8741e2e SRRH |
2934 | if (iter->snapshot && trace_empty(iter)) |
2935 | print_snapshot_help(m, iter); | |
2936 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 2937 | iter->trace->print_header(m); |
62b915f1 JO |
2938 | else |
2939 | trace_default_header(m); | |
2940 | ||
a63ce5b3 SR |
2941 | } else if (iter->leftover) { |
2942 | /* | |
2943 | * If we filled the seq_file buffer earlier, we | |
2944 | * want to just show it now. | |
2945 | */ | |
2946 | ret = trace_print_seq(m, &iter->seq); | |
2947 | ||
2948 | /* ret should this time be zero, but you never know */ | |
2949 | iter->leftover = ret; | |
2950 | ||
bc0c38d1 | 2951 | } else { |
f9896bf3 | 2952 | print_trace_line(iter); |
a63ce5b3 SR |
2953 | ret = trace_print_seq(m, &iter->seq); |
2954 | /* | |
2955 | * If we overflow the seq_file buffer, then it will | |
2956 | * ask us for this data again at start up. | |
2957 | * Use that instead. | |
2958 | * ret is 0 if seq_file write succeeded. | |
2959 | * -1 otherwise. | |
2960 | */ | |
2961 | iter->leftover = ret; | |
bc0c38d1 SR |
2962 | } |
2963 | ||
2964 | return 0; | |
2965 | } | |
2966 | ||
649e9c70 ON |
2967 | /* |
2968 | * Should be used after trace_array_get(), trace_types_lock | |
2969 | * ensures that i_cdev was already initialized. | |
2970 | */ | |
2971 | static inline int tracing_get_cpu(struct inode *inode) | |
2972 | { | |
2973 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
2974 | return (long)inode->i_cdev - 1; | |
2975 | return RING_BUFFER_ALL_CPUS; | |
2976 | } | |
2977 | ||
88e9d34c | 2978 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2979 | .start = s_start, |
2980 | .next = s_next, | |
2981 | .stop = s_stop, | |
2982 | .show = s_show, | |
bc0c38d1 SR |
2983 | }; |
2984 | ||
e309b41d | 2985 | static struct trace_iterator * |
6484c71c | 2986 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 2987 | { |
6484c71c | 2988 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 2989 | struct trace_iterator *iter; |
50e18b94 | 2990 | int cpu; |
bc0c38d1 | 2991 | |
85a2f9b4 SR |
2992 | if (tracing_disabled) |
2993 | return ERR_PTR(-ENODEV); | |
60a11774 | 2994 | |
50e18b94 | 2995 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2996 | if (!iter) |
2997 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2998 | |
6d158a81 SR |
2999 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
3000 | GFP_KERNEL); | |
93574fcc DC |
3001 | if (!iter->buffer_iter) |
3002 | goto release; | |
3003 | ||
d7350c3f FW |
3004 | /* |
3005 | * We make a copy of the current tracer to avoid concurrent | |
3006 | * changes on it while we are reading. | |
3007 | */ | |
bc0c38d1 | 3008 | mutex_lock(&trace_types_lock); |
d7350c3f | 3009 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 3010 | if (!iter->trace) |
d7350c3f | 3011 | goto fail; |
85a2f9b4 | 3012 | |
2b6080f2 | 3013 | *iter->trace = *tr->current_trace; |
d7350c3f | 3014 | |
79f55997 | 3015 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
3016 | goto fail; |
3017 | ||
12883efb SRRH |
3018 | iter->tr = tr; |
3019 | ||
3020 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
3021 | /* Currently only the top directory has a snapshot */ |
3022 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 3023 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 3024 | else |
12883efb SRRH |
3025 | #endif |
3026 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 3027 | iter->snapshot = snapshot; |
bc0c38d1 | 3028 | iter->pos = -1; |
6484c71c | 3029 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 3030 | mutex_init(&iter->mutex); |
bc0c38d1 | 3031 | |
8bba1bf5 MM |
3032 | /* Notify the tracer early; before we stop tracing. */ |
3033 | if (iter->trace && iter->trace->open) | |
a93751ca | 3034 | iter->trace->open(iter); |
8bba1bf5 | 3035 | |
12ef7d44 | 3036 | /* Annotate start of buffers if we had overruns */ |
12883efb | 3037 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
3038 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
3039 | ||
8be0709f | 3040 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 3041 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
3042 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
3043 | ||
debdd57f HT |
3044 | /* stop the trace while dumping if we are not opening "snapshot" */ |
3045 | if (!iter->snapshot) | |
2b6080f2 | 3046 | tracing_stop_tr(tr); |
2f26ebd5 | 3047 | |
ae3b5093 | 3048 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 3049 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 3050 | iter->buffer_iter[cpu] = |
12883efb | 3051 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3052 | } |
3053 | ring_buffer_read_prepare_sync(); | |
3054 | for_each_tracing_cpu(cpu) { | |
3055 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3056 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
3057 | } |
3058 | } else { | |
3059 | cpu = iter->cpu_file; | |
3928a8a2 | 3060 | iter->buffer_iter[cpu] = |
12883efb | 3061 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3062 | ring_buffer_read_prepare_sync(); |
3063 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3064 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
3065 | } |
3066 | ||
bc0c38d1 SR |
3067 | mutex_unlock(&trace_types_lock); |
3068 | ||
bc0c38d1 | 3069 | return iter; |
3928a8a2 | 3070 | |
d7350c3f | 3071 | fail: |
3928a8a2 | 3072 | mutex_unlock(&trace_types_lock); |
d7350c3f | 3073 | kfree(iter->trace); |
6d158a81 | 3074 | kfree(iter->buffer_iter); |
93574fcc | 3075 | release: |
50e18b94 JO |
3076 | seq_release_private(inode, file); |
3077 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
3078 | } |
3079 | ||
3080 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
3081 | { | |
60a11774 SR |
3082 | if (tracing_disabled) |
3083 | return -ENODEV; | |
3084 | ||
bc0c38d1 SR |
3085 | filp->private_data = inode->i_private; |
3086 | return 0; | |
3087 | } | |
3088 | ||
2e86421d GB |
3089 | bool tracing_is_disabled(void) |
3090 | { | |
3091 | return (tracing_disabled) ? true: false; | |
3092 | } | |
3093 | ||
7b85af63 SRRH |
3094 | /* |
3095 | * Open and update trace_array ref count. | |
3096 | * Must have the current trace_array passed to it. | |
3097 | */ | |
dcc30223 | 3098 | static int tracing_open_generic_tr(struct inode *inode, struct file *filp) |
7b85af63 SRRH |
3099 | { |
3100 | struct trace_array *tr = inode->i_private; | |
3101 | ||
3102 | if (tracing_disabled) | |
3103 | return -ENODEV; | |
3104 | ||
3105 | if (trace_array_get(tr) < 0) | |
3106 | return -ENODEV; | |
3107 | ||
3108 | filp->private_data = inode->i_private; | |
3109 | ||
3110 | return 0; | |
7b85af63 SRRH |
3111 | } |
3112 | ||
4fd27358 | 3113 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 3114 | { |
6484c71c | 3115 | struct trace_array *tr = inode->i_private; |
907f2784 | 3116 | struct seq_file *m = file->private_data; |
4acd4d00 | 3117 | struct trace_iterator *iter; |
3928a8a2 | 3118 | int cpu; |
bc0c38d1 | 3119 | |
ff451961 | 3120 | if (!(file->f_mode & FMODE_READ)) { |
6484c71c | 3121 | trace_array_put(tr); |
4acd4d00 | 3122 | return 0; |
ff451961 | 3123 | } |
4acd4d00 | 3124 | |
6484c71c | 3125 | /* Writes do not use seq_file */ |
4acd4d00 | 3126 | iter = m->private; |
bc0c38d1 | 3127 | mutex_lock(&trace_types_lock); |
a695cb58 | 3128 | |
3928a8a2 SR |
3129 | for_each_tracing_cpu(cpu) { |
3130 | if (iter->buffer_iter[cpu]) | |
3131 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
3132 | } | |
3133 | ||
bc0c38d1 SR |
3134 | if (iter->trace && iter->trace->close) |
3135 | iter->trace->close(iter); | |
3136 | ||
debdd57f HT |
3137 | if (!iter->snapshot) |
3138 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 3139 | tracing_start_tr(tr); |
f77d09a3 AL |
3140 | |
3141 | __trace_array_put(tr); | |
3142 | ||
bc0c38d1 SR |
3143 | mutex_unlock(&trace_types_lock); |
3144 | ||
d7350c3f | 3145 | mutex_destroy(&iter->mutex); |
b0dfa978 | 3146 | free_cpumask_var(iter->started); |
d7350c3f | 3147 | kfree(iter->trace); |
6d158a81 | 3148 | kfree(iter->buffer_iter); |
50e18b94 | 3149 | seq_release_private(inode, file); |
ff451961 | 3150 | |
bc0c38d1 SR |
3151 | return 0; |
3152 | } | |
3153 | ||
7b85af63 SRRH |
3154 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
3155 | { | |
3156 | struct trace_array *tr = inode->i_private; | |
3157 | ||
3158 | trace_array_put(tr); | |
bc0c38d1 SR |
3159 | return 0; |
3160 | } | |
3161 | ||
7b85af63 SRRH |
3162 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
3163 | { | |
3164 | struct trace_array *tr = inode->i_private; | |
3165 | ||
3166 | trace_array_put(tr); | |
3167 | ||
3168 | return single_release(inode, file); | |
3169 | } | |
3170 | ||
bc0c38d1 SR |
3171 | static int tracing_open(struct inode *inode, struct file *file) |
3172 | { | |
6484c71c | 3173 | struct trace_array *tr = inode->i_private; |
85a2f9b4 SR |
3174 | struct trace_iterator *iter; |
3175 | int ret = 0; | |
bc0c38d1 | 3176 | |
ff451961 SRRH |
3177 | if (trace_array_get(tr) < 0) |
3178 | return -ENODEV; | |
3179 | ||
4acd4d00 | 3180 | /* If this file was open for write, then erase contents */ |
6484c71c ON |
3181 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
3182 | int cpu = tracing_get_cpu(inode); | |
3183 | ||
3184 | if (cpu == RING_BUFFER_ALL_CPUS) | |
12883efb | 3185 | tracing_reset_online_cpus(&tr->trace_buffer); |
4acd4d00 | 3186 | else |
6484c71c | 3187 | tracing_reset(&tr->trace_buffer, cpu); |
4acd4d00 | 3188 | } |
bc0c38d1 | 3189 | |
4acd4d00 | 3190 | if (file->f_mode & FMODE_READ) { |
6484c71c | 3191 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
3192 | if (IS_ERR(iter)) |
3193 | ret = PTR_ERR(iter); | |
3194 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
3195 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3196 | } | |
ff451961 SRRH |
3197 | |
3198 | if (ret < 0) | |
3199 | trace_array_put(tr); | |
3200 | ||
bc0c38d1 SR |
3201 | return ret; |
3202 | } | |
3203 | ||
607e2ea1 SRRH |
3204 | /* |
3205 | * Some tracers are not suitable for instance buffers. | |
3206 | * A tracer is always available for the global array (toplevel) | |
3207 | * or if it explicitly states that it is. | |
3208 | */ | |
3209 | static bool | |
3210 | trace_ok_for_array(struct tracer *t, struct trace_array *tr) | |
3211 | { | |
3212 | return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; | |
3213 | } | |
3214 | ||
3215 | /* Find the next tracer that this trace array may use */ | |
3216 | static struct tracer * | |
3217 | get_tracer_for_array(struct trace_array *tr, struct tracer *t) | |
3218 | { | |
3219 | while (t && !trace_ok_for_array(t, tr)) | |
3220 | t = t->next; | |
3221 | ||
3222 | return t; | |
3223 | } | |
3224 | ||
e309b41d | 3225 | static void * |
bc0c38d1 SR |
3226 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3227 | { | |
607e2ea1 | 3228 | struct trace_array *tr = m->private; |
f129e965 | 3229 | struct tracer *t = v; |
bc0c38d1 SR |
3230 | |
3231 | (*pos)++; | |
3232 | ||
3233 | if (t) | |
607e2ea1 | 3234 | t = get_tracer_for_array(tr, t->next); |
bc0c38d1 | 3235 | |
bc0c38d1 SR |
3236 | return t; |
3237 | } | |
3238 | ||
3239 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3240 | { | |
607e2ea1 | 3241 | struct trace_array *tr = m->private; |
f129e965 | 3242 | struct tracer *t; |
bc0c38d1 SR |
3243 | loff_t l = 0; |
3244 | ||
3245 | mutex_lock(&trace_types_lock); | |
607e2ea1 SRRH |
3246 | |
3247 | t = get_tracer_for_array(tr, trace_types); | |
3248 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
3249 | ; | |
bc0c38d1 SR |
3250 | |
3251 | return t; | |
3252 | } | |
3253 | ||
3254 | static void t_stop(struct seq_file *m, void *p) | |
3255 | { | |
3256 | mutex_unlock(&trace_types_lock); | |
3257 | } | |
3258 | ||
3259 | static int t_show(struct seq_file *m, void *v) | |
3260 | { | |
3261 | struct tracer *t = v; | |
3262 | ||
3263 | if (!t) | |
3264 | return 0; | |
3265 | ||
fa6f0cc7 | 3266 | seq_puts(m, t->name); |
bc0c38d1 SR |
3267 | if (t->next) |
3268 | seq_putc(m, ' '); | |
3269 | else | |
3270 | seq_putc(m, '\n'); | |
3271 | ||
3272 | return 0; | |
3273 | } | |
3274 | ||
88e9d34c | 3275 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
3276 | .start = t_start, |
3277 | .next = t_next, | |
3278 | .stop = t_stop, | |
3279 | .show = t_show, | |
bc0c38d1 SR |
3280 | }; |
3281 | ||
3282 | static int show_traces_open(struct inode *inode, struct file *file) | |
3283 | { | |
607e2ea1 SRRH |
3284 | struct trace_array *tr = inode->i_private; |
3285 | struct seq_file *m; | |
3286 | int ret; | |
3287 | ||
60a11774 SR |
3288 | if (tracing_disabled) |
3289 | return -ENODEV; | |
3290 | ||
607e2ea1 SRRH |
3291 | ret = seq_open(file, &show_traces_seq_ops); |
3292 | if (ret) | |
3293 | return ret; | |
3294 | ||
3295 | m = file->private_data; | |
3296 | m->private = tr; | |
3297 | ||
3298 | return 0; | |
bc0c38d1 SR |
3299 | } |
3300 | ||
4acd4d00 SR |
3301 | static ssize_t |
3302 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
3303 | size_t count, loff_t *ppos) | |
3304 | { | |
3305 | return count; | |
3306 | } | |
3307 | ||
098c879e | 3308 | loff_t tracing_lseek(struct file *file, loff_t offset, int whence) |
364829b1 | 3309 | { |
098c879e SRRH |
3310 | int ret; |
3311 | ||
364829b1 | 3312 | if (file->f_mode & FMODE_READ) |
098c879e | 3313 | ret = seq_lseek(file, offset, whence); |
364829b1 | 3314 | else |
098c879e SRRH |
3315 | file->f_pos = ret = 0; |
3316 | ||
3317 | return ret; | |
364829b1 SP |
3318 | } |
3319 | ||
5e2336a0 | 3320 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
3321 | .open = tracing_open, |
3322 | .read = seq_read, | |
4acd4d00 | 3323 | .write = tracing_write_stub, |
098c879e | 3324 | .llseek = tracing_lseek, |
4bf39a94 | 3325 | .release = tracing_release, |
bc0c38d1 SR |
3326 | }; |
3327 | ||
5e2336a0 | 3328 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
3329 | .open = show_traces_open, |
3330 | .read = seq_read, | |
3331 | .release = seq_release, | |
b444786f | 3332 | .llseek = seq_lseek, |
c7078de1 IM |
3333 | }; |
3334 | ||
36dfe925 IM |
3335 | /* |
3336 | * The tracer itself will not take this lock, but still we want | |
3337 | * to provide a consistent cpumask to user-space: | |
3338 | */ | |
3339 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
3340 | ||
3341 | /* | |
3342 | * Temporary storage for the character representation of the | |
3343 | * CPU bitmask (and one more byte for the newline): | |
3344 | */ | |
3345 | static char mask_str[NR_CPUS + 1]; | |
3346 | ||
c7078de1 IM |
3347 | static ssize_t |
3348 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
3349 | size_t count, loff_t *ppos) | |
3350 | { | |
ccfe9e42 | 3351 | struct trace_array *tr = file_inode(filp)->i_private; |
36dfe925 | 3352 | int len; |
c7078de1 IM |
3353 | |
3354 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 3355 | |
ccfe9e42 | 3356 | len = cpumask_scnprintf(mask_str, count, tr->tracing_cpumask); |
36dfe925 IM |
3357 | if (count - len < 2) { |
3358 | count = -EINVAL; | |
3359 | goto out_err; | |
3360 | } | |
3361 | len += sprintf(mask_str + len, "\n"); | |
3362 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
3363 | ||
3364 | out_err: | |
c7078de1 IM |
3365 | mutex_unlock(&tracing_cpumask_update_lock); |
3366 | ||
3367 | return count; | |
3368 | } | |
3369 | ||
3370 | static ssize_t | |
3371 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
3372 | size_t count, loff_t *ppos) | |
3373 | { | |
ccfe9e42 | 3374 | struct trace_array *tr = file_inode(filp)->i_private; |
9e01c1b7 | 3375 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 3376 | int err, cpu; |
9e01c1b7 RR |
3377 | |
3378 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
3379 | return -ENOMEM; | |
c7078de1 | 3380 | |
9e01c1b7 | 3381 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 3382 | if (err) |
36dfe925 IM |
3383 | goto err_unlock; |
3384 | ||
215368e8 LZ |
3385 | mutex_lock(&tracing_cpumask_update_lock); |
3386 | ||
a5e25883 | 3387 | local_irq_disable(); |
0b9b12c1 | 3388 | arch_spin_lock(&tr->max_lock); |
ab46428c | 3389 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
3390 | /* |
3391 | * Increase/decrease the disabled counter if we are | |
3392 | * about to flip a bit in the cpumask: | |
3393 | */ | |
ccfe9e42 | 3394 | if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3395 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3396 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3397 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 3398 | } |
ccfe9e42 | 3399 | if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3400 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3401 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3402 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
3403 | } |
3404 | } | |
0b9b12c1 | 3405 | arch_spin_unlock(&tr->max_lock); |
a5e25883 | 3406 | local_irq_enable(); |
36dfe925 | 3407 | |
ccfe9e42 | 3408 | cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
3409 | |
3410 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 3411 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
3412 | |
3413 | return count; | |
36dfe925 IM |
3414 | |
3415 | err_unlock: | |
215368e8 | 3416 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
3417 | |
3418 | return err; | |
c7078de1 IM |
3419 | } |
3420 | ||
5e2336a0 | 3421 | static const struct file_operations tracing_cpumask_fops = { |
ccfe9e42 | 3422 | .open = tracing_open_generic_tr, |
c7078de1 IM |
3423 | .read = tracing_cpumask_read, |
3424 | .write = tracing_cpumask_write, | |
ccfe9e42 | 3425 | .release = tracing_release_generic_tr, |
b444786f | 3426 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3427 | }; |
3428 | ||
fdb372ed | 3429 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 3430 | { |
d8e83d26 | 3431 | struct tracer_opt *trace_opts; |
2b6080f2 | 3432 | struct trace_array *tr = m->private; |
d8e83d26 | 3433 | u32 tracer_flags; |
d8e83d26 | 3434 | int i; |
adf9f195 | 3435 | |
d8e83d26 | 3436 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3437 | tracer_flags = tr->current_trace->flags->val; |
3438 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 3439 | |
bc0c38d1 SR |
3440 | for (i = 0; trace_options[i]; i++) { |
3441 | if (trace_flags & (1 << i)) | |
fdb372ed | 3442 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 3443 | else |
fdb372ed | 3444 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
3445 | } |
3446 | ||
adf9f195 FW |
3447 | for (i = 0; trace_opts[i].name; i++) { |
3448 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 3449 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 3450 | else |
fdb372ed | 3451 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 3452 | } |
d8e83d26 | 3453 | mutex_unlock(&trace_types_lock); |
adf9f195 | 3454 | |
fdb372ed | 3455 | return 0; |
bc0c38d1 | 3456 | } |
bc0c38d1 | 3457 | |
8c1a49ae | 3458 | static int __set_tracer_option(struct trace_array *tr, |
8d18eaaf LZ |
3459 | struct tracer_flags *tracer_flags, |
3460 | struct tracer_opt *opts, int neg) | |
3461 | { | |
8c1a49ae | 3462 | struct tracer *trace = tr->current_trace; |
8d18eaaf | 3463 | int ret; |
bc0c38d1 | 3464 | |
8c1a49ae | 3465 | ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); |
8d18eaaf LZ |
3466 | if (ret) |
3467 | return ret; | |
3468 | ||
3469 | if (neg) | |
3470 | tracer_flags->val &= ~opts->bit; | |
3471 | else | |
3472 | tracer_flags->val |= opts->bit; | |
3473 | return 0; | |
bc0c38d1 SR |
3474 | } |
3475 | ||
adf9f195 | 3476 | /* Try to assign a tracer specific option */ |
8c1a49ae | 3477 | static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) |
adf9f195 | 3478 | { |
8c1a49ae | 3479 | struct tracer *trace = tr->current_trace; |
7770841e | 3480 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 3481 | struct tracer_opt *opts = NULL; |
8d18eaaf | 3482 | int i; |
adf9f195 | 3483 | |
7770841e Z |
3484 | for (i = 0; tracer_flags->opts[i].name; i++) { |
3485 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 3486 | |
8d18eaaf | 3487 | if (strcmp(cmp, opts->name) == 0) |
8c1a49ae | 3488 | return __set_tracer_option(tr, trace->flags, opts, neg); |
adf9f195 | 3489 | } |
adf9f195 | 3490 | |
8d18eaaf | 3491 | return -EINVAL; |
adf9f195 FW |
3492 | } |
3493 | ||
613f04a0 SRRH |
3494 | /* Some tracers require overwrite to stay enabled */ |
3495 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
3496 | { | |
3497 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
3498 | return -1; | |
3499 | ||
3500 | return 0; | |
3501 | } | |
3502 | ||
2b6080f2 | 3503 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
3504 | { |
3505 | /* do nothing if flag is already set */ | |
3506 | if (!!(trace_flags & mask) == !!enabled) | |
613f04a0 SRRH |
3507 | return 0; |
3508 | ||
3509 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 | 3510 | if (tr->current_trace->flag_changed) |
bf6065b5 | 3511 | if (tr->current_trace->flag_changed(tr, mask, !!enabled)) |
613f04a0 | 3512 | return -EINVAL; |
af4617bd SR |
3513 | |
3514 | if (enabled) | |
3515 | trace_flags |= mask; | |
3516 | else | |
3517 | trace_flags &= ~mask; | |
e870e9a1 LZ |
3518 | |
3519 | if (mask == TRACE_ITER_RECORD_CMD) | |
3520 | trace_event_enable_cmd_record(enabled); | |
750912fa | 3521 | |
80902822 | 3522 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 3523 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 3524 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 3525 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
3526 | #endif |
3527 | } | |
81698831 SR |
3528 | |
3529 | if (mask == TRACE_ITER_PRINTK) | |
3530 | trace_printk_start_stop_comm(enabled); | |
613f04a0 SRRH |
3531 | |
3532 | return 0; | |
af4617bd SR |
3533 | } |
3534 | ||
2b6080f2 | 3535 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 3536 | { |
8d18eaaf | 3537 | char *cmp; |
bc0c38d1 | 3538 | int neg = 0; |
613f04a0 | 3539 | int ret = -ENODEV; |
bc0c38d1 SR |
3540 | int i; |
3541 | ||
7bcfaf54 | 3542 | cmp = strstrip(option); |
bc0c38d1 | 3543 | |
8d18eaaf | 3544 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3545 | neg = 1; |
3546 | cmp += 2; | |
3547 | } | |
3548 | ||
69d34da2 SRRH |
3549 | mutex_lock(&trace_types_lock); |
3550 | ||
bc0c38d1 | 3551 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3552 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3553 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3554 | break; |
3555 | } | |
3556 | } | |
adf9f195 FW |
3557 | |
3558 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3559 | if (!trace_options[i]) |
8c1a49ae | 3560 | ret = set_tracer_option(tr, cmp, neg); |
69d34da2 SRRH |
3561 | |
3562 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3563 | |
7bcfaf54 SR |
3564 | return ret; |
3565 | } | |
3566 | ||
3567 | static ssize_t | |
3568 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3569 | size_t cnt, loff_t *ppos) | |
3570 | { | |
2b6080f2 SR |
3571 | struct seq_file *m = filp->private_data; |
3572 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3573 | char buf[64]; |
613f04a0 | 3574 | int ret; |
7bcfaf54 SR |
3575 | |
3576 | if (cnt >= sizeof(buf)) | |
3577 | return -EINVAL; | |
3578 | ||
3579 | if (copy_from_user(&buf, ubuf, cnt)) | |
3580 | return -EFAULT; | |
3581 | ||
a8dd2176 SR |
3582 | buf[cnt] = 0; |
3583 | ||
2b6080f2 | 3584 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
3585 | if (ret < 0) |
3586 | return ret; | |
7bcfaf54 | 3587 | |
cf8517cf | 3588 | *ppos += cnt; |
bc0c38d1 SR |
3589 | |
3590 | return cnt; | |
3591 | } | |
3592 | ||
fdb372ed LZ |
3593 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
3594 | { | |
7b85af63 | 3595 | struct trace_array *tr = inode->i_private; |
f77d09a3 | 3596 | int ret; |
7b85af63 | 3597 | |
fdb372ed LZ |
3598 | if (tracing_disabled) |
3599 | return -ENODEV; | |
2b6080f2 | 3600 | |
7b85af63 SRRH |
3601 | if (trace_array_get(tr) < 0) |
3602 | return -ENODEV; | |
3603 | ||
f77d09a3 AL |
3604 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
3605 | if (ret < 0) | |
3606 | trace_array_put(tr); | |
3607 | ||
3608 | return ret; | |
fdb372ed LZ |
3609 | } |
3610 | ||
5e2336a0 | 3611 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
3612 | .open = tracing_trace_options_open, |
3613 | .read = seq_read, | |
3614 | .llseek = seq_lseek, | |
7b85af63 | 3615 | .release = tracing_single_release_tr, |
ee6bce52 | 3616 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
3617 | }; |
3618 | ||
7bd2f24c IM |
3619 | static const char readme_msg[] = |
3620 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
3621 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
3622 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
3623 | " Important files:\n" | |
3624 | " trace\t\t\t- The static contents of the buffer\n" | |
3625 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
3626 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
3627 | " current_tracer\t- function and latency tracers\n" | |
3628 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
3629 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" | |
3630 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
3631 | " trace_clock\t\t-change the clock used to order events\n" | |
3632 | " local: Per cpu clock but may not be synced across CPUs\n" | |
3633 | " global: Synced across CPUs but slows tracing down.\n" | |
3634 | " counter: Not a clock, but just an increment\n" | |
3635 | " uptime: Jiffy counter from time of boot\n" | |
3636 | " perf: Same clock that perf events use\n" | |
3637 | #ifdef CONFIG_X86_64 | |
3638 | " x86-tsc: TSC cycle counter\n" | |
3639 | #endif | |
3640 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" | |
3641 | " tracing_cpumask\t- Limit which CPUs to trace\n" | |
3642 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
3643 | "\t\t\t Remove sub-buffer with rmdir\n" | |
3644 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
71485c45 SRRH |
3645 | "\t\t\t Disable an option by adding a suffix 'no' to the\n" |
3646 | "\t\t\t option name\n" | |
939c7a4f | 3647 | " saved_cmdlines_size\t- echo command number in here to store comm-pid list\n" |
22f45649 SRRH |
3648 | #ifdef CONFIG_DYNAMIC_FTRACE |
3649 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
71485c45 SRRH |
3650 | " set_ftrace_filter\t- echo function name in here to only trace these\n" |
3651 | "\t\t\t functions\n" | |
3652 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3653 | "\t modules: Can select a group via module\n" | |
3654 | "\t Format: :mod:<module-name>\n" | |
3655 | "\t example: echo :mod:ext3 > set_ftrace_filter\n" | |
3656 | "\t triggers: a command to perform when function is hit\n" | |
3657 | "\t Format: <function>:<trigger>[:count]\n" | |
3658 | "\t trigger: traceon, traceoff\n" | |
3659 | "\t\t enable_event:<system>:<event>\n" | |
3660 | "\t\t disable_event:<system>:<event>\n" | |
22f45649 | 3661 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3662 | "\t\t stacktrace\n" |
22f45649 SRRH |
3663 | #endif |
3664 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3665 | "\t\t snapshot\n" |
22f45649 | 3666 | #endif |
17a280ea SRRH |
3667 | "\t\t dump\n" |
3668 | "\t\t cpudump\n" | |
71485c45 SRRH |
3669 | "\t example: echo do_fault:traceoff > set_ftrace_filter\n" |
3670 | "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
3671 | "\t The first one will disable tracing every time do_fault is hit\n" | |
3672 | "\t The second will disable tracing at most 3 times when do_trap is hit\n" | |
3673 | "\t The first time do trap is hit and it disables tracing, the\n" | |
3674 | "\t counter will decrement to 2. If tracing is already disabled,\n" | |
3675 | "\t the counter will not decrement. It only decrements when the\n" | |
3676 | "\t trigger did work\n" | |
3677 | "\t To remove trigger without count:\n" | |
3678 | "\t echo '!<function>:<trigger> > set_ftrace_filter\n" | |
3679 | "\t To remove trigger with a count:\n" | |
3680 | "\t echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
22f45649 | 3681 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" |
71485c45 SRRH |
3682 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" |
3683 | "\t modules: Can select a group via module command :mod:\n" | |
3684 | "\t Does not accept triggers\n" | |
22f45649 SRRH |
3685 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
3686 | #ifdef CONFIG_FUNCTION_TRACER | |
71485c45 SRRH |
3687 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" |
3688 | "\t\t (function)\n" | |
22f45649 SRRH |
3689 | #endif |
3690 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
3691 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
d048a8c7 | 3692 | " set_graph_notrace\t- Do not trace the nested calls of a function (function_graph)\n" |
22f45649 SRRH |
3693 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" |
3694 | #endif | |
3695 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 SRRH |
3696 | "\n snapshot\t\t- Like 'trace' but shows the content of the static\n" |
3697 | "\t\t\t snapshot buffer. Read the contents for more\n" | |
3698 | "\t\t\t information\n" | |
22f45649 | 3699 | #endif |
991821c8 | 3700 | #ifdef CONFIG_STACK_TRACER |
22f45649 SRRH |
3701 | " stack_trace\t\t- Shows the max stack trace when active\n" |
3702 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
71485c45 SRRH |
3703 | "\t\t\t Write into this file to reset the max size (trigger a\n" |
3704 | "\t\t\t new trace)\n" | |
22f45649 | 3705 | #ifdef CONFIG_DYNAMIC_FTRACE |
71485c45 SRRH |
3706 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n" |
3707 | "\t\t\t traces\n" | |
22f45649 | 3708 | #endif |
991821c8 | 3709 | #endif /* CONFIG_STACK_TRACER */ |
26f25564 TZ |
3710 | " events/\t\t- Directory containing all trace event subsystems:\n" |
3711 | " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" | |
3712 | " events/<system>/\t- Directory containing all trace events for <system>:\n" | |
71485c45 SRRH |
3713 | " enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n" |
3714 | "\t\t\t events\n" | |
26f25564 | 3715 | " filter\t\t- If set, only events passing filter are traced\n" |
71485c45 SRRH |
3716 | " events/<system>/<event>/\t- Directory containing control files for\n" |
3717 | "\t\t\t <event>:\n" | |
26f25564 TZ |
3718 | " enable\t\t- Write 0/1 to enable/disable tracing of <event>\n" |
3719 | " filter\t\t- If set, only events passing filter are traced\n" | |
3720 | " trigger\t\t- If set, a command to perform when event is hit\n" | |
71485c45 SRRH |
3721 | "\t Format: <trigger>[:count][if <filter>]\n" |
3722 | "\t trigger: traceon, traceoff\n" | |
3723 | "\t enable_event:<system>:<event>\n" | |
3724 | "\t disable_event:<system>:<event>\n" | |
26f25564 | 3725 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3726 | "\t\t stacktrace\n" |
26f25564 TZ |
3727 | #endif |
3728 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3729 | "\t\t snapshot\n" |
26f25564 | 3730 | #endif |
71485c45 SRRH |
3731 | "\t example: echo traceoff > events/block/block_unplug/trigger\n" |
3732 | "\t echo traceoff:3 > events/block/block_unplug/trigger\n" | |
3733 | "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" | |
3734 | "\t events/block/block_unplug/trigger\n" | |
3735 | "\t The first disables tracing every time block_unplug is hit.\n" | |
3736 | "\t The second disables tracing the first 3 times block_unplug is hit.\n" | |
3737 | "\t The third enables the kmalloc event the first 3 times block_unplug\n" | |
3738 | "\t is hit and has value of greater than 1 for the 'nr_rq' event field.\n" | |
3739 | "\t Like function triggers, the counter is only decremented if it\n" | |
3740 | "\t enabled or disabled tracing.\n" | |
3741 | "\t To remove a trigger without a count:\n" | |
3742 | "\t echo '!<trigger> > <system>/<event>/trigger\n" | |
3743 | "\t To remove a trigger with a count:\n" | |
3744 | "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" | |
3745 | "\t Filters can be ignored when removing a trigger.\n" | |
7bd2f24c IM |
3746 | ; |
3747 | ||
3748 | static ssize_t | |
3749 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
3750 | size_t cnt, loff_t *ppos) | |
3751 | { | |
3752 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
3753 | readme_msg, strlen(readme_msg)); | |
3754 | } | |
3755 | ||
5e2336a0 | 3756 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
3757 | .open = tracing_open_generic, |
3758 | .read = tracing_readme_read, | |
b444786f | 3759 | .llseek = generic_file_llseek, |
7bd2f24c IM |
3760 | }; |
3761 | ||
42584c81 YY |
3762 | static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos) |
3763 | { | |
3764 | unsigned int *ptr = v; | |
69abe6a5 | 3765 | |
42584c81 YY |
3766 | if (*pos || m->count) |
3767 | ptr++; | |
69abe6a5 | 3768 | |
42584c81 | 3769 | (*pos)++; |
69abe6a5 | 3770 | |
939c7a4f YY |
3771 | for (; ptr < &savedcmd->map_cmdline_to_pid[savedcmd->cmdline_num]; |
3772 | ptr++) { | |
42584c81 YY |
3773 | if (*ptr == -1 || *ptr == NO_CMDLINE_MAP) |
3774 | continue; | |
69abe6a5 | 3775 | |
42584c81 YY |
3776 | return ptr; |
3777 | } | |
69abe6a5 | 3778 | |
42584c81 YY |
3779 | return NULL; |
3780 | } | |
3781 | ||
3782 | static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos) | |
3783 | { | |
3784 | void *v; | |
3785 | loff_t l = 0; | |
69abe6a5 | 3786 | |
4c27e756 SRRH |
3787 | preempt_disable(); |
3788 | arch_spin_lock(&trace_cmdline_lock); | |
3789 | ||
939c7a4f | 3790 | v = &savedcmd->map_cmdline_to_pid[0]; |
42584c81 YY |
3791 | while (l <= *pos) { |
3792 | v = saved_cmdlines_next(m, v, &l); | |
3793 | if (!v) | |
3794 | return NULL; | |
69abe6a5 AP |
3795 | } |
3796 | ||
42584c81 YY |
3797 | return v; |
3798 | } | |
3799 | ||
3800 | static void saved_cmdlines_stop(struct seq_file *m, void *v) | |
3801 | { | |
4c27e756 SRRH |
3802 | arch_spin_unlock(&trace_cmdline_lock); |
3803 | preempt_enable(); | |
42584c81 | 3804 | } |
69abe6a5 | 3805 | |
42584c81 YY |
3806 | static int saved_cmdlines_show(struct seq_file *m, void *v) |
3807 | { | |
3808 | char buf[TASK_COMM_LEN]; | |
3809 | unsigned int *pid = v; | |
69abe6a5 | 3810 | |
4c27e756 | 3811 | __trace_find_cmdline(*pid, buf); |
42584c81 YY |
3812 | seq_printf(m, "%d %s\n", *pid, buf); |
3813 | return 0; | |
3814 | } | |
3815 | ||
3816 | static const struct seq_operations tracing_saved_cmdlines_seq_ops = { | |
3817 | .start = saved_cmdlines_start, | |
3818 | .next = saved_cmdlines_next, | |
3819 | .stop = saved_cmdlines_stop, | |
3820 | .show = saved_cmdlines_show, | |
3821 | }; | |
3822 | ||
3823 | static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp) | |
3824 | { | |
3825 | if (tracing_disabled) | |
3826 | return -ENODEV; | |
3827 | ||
3828 | return seq_open(filp, &tracing_saved_cmdlines_seq_ops); | |
69abe6a5 AP |
3829 | } |
3830 | ||
3831 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
42584c81 YY |
3832 | .open = tracing_saved_cmdlines_open, |
3833 | .read = seq_read, | |
3834 | .llseek = seq_lseek, | |
3835 | .release = seq_release, | |
69abe6a5 AP |
3836 | }; |
3837 | ||
939c7a4f YY |
3838 | static ssize_t |
3839 | tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf, | |
3840 | size_t cnt, loff_t *ppos) | |
3841 | { | |
3842 | char buf[64]; | |
3843 | int r; | |
3844 | ||
3845 | arch_spin_lock(&trace_cmdline_lock); | |
a6af8fbf | 3846 | r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num); |
939c7a4f YY |
3847 | arch_spin_unlock(&trace_cmdline_lock); |
3848 | ||
3849 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3850 | } | |
3851 | ||
3852 | static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s) | |
3853 | { | |
3854 | kfree(s->saved_cmdlines); | |
3855 | kfree(s->map_cmdline_to_pid); | |
3856 | kfree(s); | |
3857 | } | |
3858 | ||
3859 | static int tracing_resize_saved_cmdlines(unsigned int val) | |
3860 | { | |
3861 | struct saved_cmdlines_buffer *s, *savedcmd_temp; | |
3862 | ||
a6af8fbf | 3863 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
939c7a4f YY |
3864 | if (!s) |
3865 | return -ENOMEM; | |
3866 | ||
3867 | if (allocate_cmdlines_buffer(val, s) < 0) { | |
3868 | kfree(s); | |
3869 | return -ENOMEM; | |
3870 | } | |
3871 | ||
3872 | arch_spin_lock(&trace_cmdline_lock); | |
3873 | savedcmd_temp = savedcmd; | |
3874 | savedcmd = s; | |
3875 | arch_spin_unlock(&trace_cmdline_lock); | |
3876 | free_saved_cmdlines_buffer(savedcmd_temp); | |
3877 | ||
3878 | return 0; | |
3879 | } | |
3880 | ||
3881 | static ssize_t | |
3882 | tracing_saved_cmdlines_size_write(struct file *filp, const char __user *ubuf, | |
3883 | size_t cnt, loff_t *ppos) | |
3884 | { | |
3885 | unsigned long val; | |
3886 | int ret; | |
3887 | ||
3888 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
3889 | if (ret) | |
3890 | return ret; | |
3891 | ||
3892 | /* must have at least 1 entry or less than PID_MAX_DEFAULT */ | |
3893 | if (!val || val > PID_MAX_DEFAULT) | |
3894 | return -EINVAL; | |
3895 | ||
3896 | ret = tracing_resize_saved_cmdlines((unsigned int)val); | |
3897 | if (ret < 0) | |
3898 | return ret; | |
3899 | ||
3900 | *ppos += cnt; | |
3901 | ||
3902 | return cnt; | |
3903 | } | |
3904 | ||
3905 | static const struct file_operations tracing_saved_cmdlines_size_fops = { | |
3906 | .open = tracing_open_generic, | |
3907 | .read = tracing_saved_cmdlines_size_read, | |
3908 | .write = tracing_saved_cmdlines_size_write, | |
3909 | }; | |
3910 | ||
bc0c38d1 SR |
3911 | static ssize_t |
3912 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
3913 | size_t cnt, loff_t *ppos) | |
3914 | { | |
2b6080f2 | 3915 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 3916 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
3917 | int r; |
3918 | ||
3919 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 3920 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
3921 | mutex_unlock(&trace_types_lock); |
3922 | ||
4bf39a94 | 3923 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3924 | } |
3925 | ||
b6f11df2 ACM |
3926 | int tracer_init(struct tracer *t, struct trace_array *tr) |
3927 | { | |
12883efb | 3928 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
3929 | return t->init(tr); |
3930 | } | |
3931 | ||
12883efb | 3932 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
3933 | { |
3934 | int cpu; | |
737223fb | 3935 | |
438ced17 | 3936 | for_each_tracing_cpu(cpu) |
12883efb | 3937 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
3938 | } |
3939 | ||
12883efb | 3940 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 3941 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
3942 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
3943 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
3944 | { |
3945 | int cpu, ret = 0; | |
3946 | ||
3947 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
3948 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
3949 | ret = ring_buffer_resize(trace_buf->buffer, |
3950 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
3951 | if (ret < 0) |
3952 | break; | |
12883efb SRRH |
3953 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
3954 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
3955 | } |
3956 | } else { | |
12883efb SRRH |
3957 | ret = ring_buffer_resize(trace_buf->buffer, |
3958 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 3959 | if (ret == 0) |
12883efb SRRH |
3960 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
3961 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
3962 | } |
3963 | ||
3964 | return ret; | |
3965 | } | |
12883efb | 3966 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 3967 | |
2b6080f2 SR |
3968 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
3969 | unsigned long size, int cpu) | |
73c5162a SR |
3970 | { |
3971 | int ret; | |
3972 | ||
3973 | /* | |
3974 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3975 | * we use the size that was given, and we can forget about |
3976 | * expanding it later. | |
73c5162a | 3977 | */ |
55034cd6 | 3978 | ring_buffer_expanded = true; |
73c5162a | 3979 | |
b382ede6 | 3980 | /* May be called before buffers are initialized */ |
12883efb | 3981 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
3982 | return 0; |
3983 | ||
12883efb | 3984 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
3985 | if (ret < 0) |
3986 | return ret; | |
3987 | ||
12883efb | 3988 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
3989 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
3990 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
3991 | goto out; |
3992 | ||
12883efb | 3993 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 3994 | if (ret < 0) { |
12883efb SRRH |
3995 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
3996 | &tr->trace_buffer, cpu); | |
73c5162a | 3997 | if (r < 0) { |
a123c52b SR |
3998 | /* |
3999 | * AARGH! We are left with different | |
4000 | * size max buffer!!!! | |
4001 | * The max buffer is our "snapshot" buffer. | |
4002 | * When a tracer needs a snapshot (one of the | |
4003 | * latency tracers), it swaps the max buffer | |
4004 | * with the saved snap shot. We succeeded to | |
4005 | * update the size of the main buffer, but failed to | |
4006 | * update the size of the max buffer. But when we tried | |
4007 | * to reset the main buffer to the original size, we | |
4008 | * failed there too. This is very unlikely to | |
4009 | * happen, but if it does, warn and kill all | |
4010 | * tracing. | |
4011 | */ | |
73c5162a SR |
4012 | WARN_ON(1); |
4013 | tracing_disabled = 1; | |
4014 | } | |
4015 | return ret; | |
4016 | } | |
4017 | ||
438ced17 | 4018 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 4019 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 4020 | else |
12883efb | 4021 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 4022 | |
ef710e10 | 4023 | out: |
12883efb SRRH |
4024 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
4025 | ||
438ced17 | 4026 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 4027 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 4028 | else |
12883efb | 4029 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
4030 | |
4031 | return ret; | |
4032 | } | |
4033 | ||
2b6080f2 SR |
4034 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
4035 | unsigned long size, int cpu_id) | |
4f271a2a | 4036 | { |
83f40318 | 4037 | int ret = size; |
4f271a2a VN |
4038 | |
4039 | mutex_lock(&trace_types_lock); | |
4040 | ||
438ced17 VN |
4041 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
4042 | /* make sure, this cpu is enabled in the mask */ | |
4043 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
4044 | ret = -EINVAL; | |
4045 | goto out; | |
4046 | } | |
4047 | } | |
4f271a2a | 4048 | |
2b6080f2 | 4049 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
4050 | if (ret < 0) |
4051 | ret = -ENOMEM; | |
4052 | ||
438ced17 | 4053 | out: |
4f271a2a VN |
4054 | mutex_unlock(&trace_types_lock); |
4055 | ||
4056 | return ret; | |
4057 | } | |
4058 | ||
ef710e10 | 4059 | |
1852fcce SR |
4060 | /** |
4061 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
4062 | * | |
4063 | * To save on memory when the tracing is never used on a system with it | |
4064 | * configured in. The ring buffers are set to a minimum size. But once | |
4065 | * a user starts to use the tracing facility, then they need to grow | |
4066 | * to their default size. | |
4067 | * | |
4068 | * This function is to be called when a tracer is about to be used. | |
4069 | */ | |
4070 | int tracing_update_buffers(void) | |
4071 | { | |
4072 | int ret = 0; | |
4073 | ||
1027fcb2 | 4074 | mutex_lock(&trace_types_lock); |
1852fcce | 4075 | if (!ring_buffer_expanded) |
2b6080f2 | 4076 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 4077 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 4078 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
4079 | |
4080 | return ret; | |
4081 | } | |
4082 | ||
577b785f SR |
4083 | struct trace_option_dentry; |
4084 | ||
4085 | static struct trace_option_dentry * | |
2b6080f2 | 4086 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f SR |
4087 | |
4088 | static void | |
4089 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
4090 | ||
6b450d25 SRRH |
4091 | /* |
4092 | * Used to clear out the tracer before deletion of an instance. | |
4093 | * Must have trace_types_lock held. | |
4094 | */ | |
4095 | static void tracing_set_nop(struct trace_array *tr) | |
4096 | { | |
4097 | if (tr->current_trace == &nop_trace) | |
4098 | return; | |
4099 | ||
50512ab5 | 4100 | tr->current_trace->enabled--; |
6b450d25 SRRH |
4101 | |
4102 | if (tr->current_trace->reset) | |
4103 | tr->current_trace->reset(tr); | |
4104 | ||
4105 | tr->current_trace = &nop_trace; | |
4106 | } | |
4107 | ||
09d23a1d | 4108 | static void update_tracer_options(struct trace_array *tr, struct tracer *t) |
bc0c38d1 | 4109 | { |
577b785f | 4110 | static struct trace_option_dentry *topts; |
09d23a1d SRRH |
4111 | |
4112 | /* Only enable if the directory has been created already. */ | |
4113 | if (!tr->dir) | |
4114 | return; | |
4115 | ||
4116 | /* Currently, only the top instance has options */ | |
4117 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL)) | |
4118 | return; | |
4119 | ||
4120 | destroy_trace_option_files(topts); | |
4121 | topts = create_trace_option_files(tr, t); | |
4122 | } | |
4123 | ||
4124 | static int tracing_set_tracer(struct trace_array *tr, const char *buf) | |
4125 | { | |
bc0c38d1 | 4126 | struct tracer *t; |
12883efb | 4127 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 4128 | bool had_max_tr; |
12883efb | 4129 | #endif |
d9e54076 | 4130 | int ret = 0; |
bc0c38d1 | 4131 | |
1027fcb2 SR |
4132 | mutex_lock(&trace_types_lock); |
4133 | ||
73c5162a | 4134 | if (!ring_buffer_expanded) { |
2b6080f2 | 4135 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 4136 | RING_BUFFER_ALL_CPUS); |
73c5162a | 4137 | if (ret < 0) |
59f586db | 4138 | goto out; |
73c5162a SR |
4139 | ret = 0; |
4140 | } | |
4141 | ||
bc0c38d1 SR |
4142 | for (t = trace_types; t; t = t->next) { |
4143 | if (strcmp(t->name, buf) == 0) | |
4144 | break; | |
4145 | } | |
c2931e05 FW |
4146 | if (!t) { |
4147 | ret = -EINVAL; | |
4148 | goto out; | |
4149 | } | |
2b6080f2 | 4150 | if (t == tr->current_trace) |
bc0c38d1 SR |
4151 | goto out; |
4152 | ||
607e2ea1 SRRH |
4153 | /* Some tracers are only allowed for the top level buffer */ |
4154 | if (!trace_ok_for_array(t, tr)) { | |
4155 | ret = -EINVAL; | |
4156 | goto out; | |
4157 | } | |
4158 | ||
cf6ab6d9 SRRH |
4159 | /* If trace pipe files are being read, we can't change the tracer */ |
4160 | if (tr->current_trace->ref) { | |
4161 | ret = -EBUSY; | |
4162 | goto out; | |
4163 | } | |
4164 | ||
9f029e83 | 4165 | trace_branch_disable(); |
613f04a0 | 4166 | |
50512ab5 | 4167 | tr->current_trace->enabled--; |
613f04a0 | 4168 | |
2b6080f2 SR |
4169 | if (tr->current_trace->reset) |
4170 | tr->current_trace->reset(tr); | |
34600f0e | 4171 | |
12883efb | 4172 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 4173 | tr->current_trace = &nop_trace; |
34600f0e | 4174 | |
45ad21ca SRRH |
4175 | #ifdef CONFIG_TRACER_MAX_TRACE |
4176 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
4177 | |
4178 | if (had_max_tr && !t->use_max_tr) { | |
4179 | /* | |
4180 | * We need to make sure that the update_max_tr sees that | |
4181 | * current_trace changed to nop_trace to keep it from | |
4182 | * swapping the buffers after we resize it. | |
4183 | * The update_max_tr is called from interrupts disabled | |
4184 | * so a synchronized_sched() is sufficient. | |
4185 | */ | |
4186 | synchronize_sched(); | |
3209cff4 | 4187 | free_snapshot(tr); |
ef710e10 | 4188 | } |
12883efb | 4189 | #endif |
09d23a1d | 4190 | update_tracer_options(tr, t); |
12883efb SRRH |
4191 | |
4192 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 4193 | if (t->use_max_tr && !had_max_tr) { |
3209cff4 | 4194 | ret = alloc_snapshot(tr); |
d60da506 HT |
4195 | if (ret < 0) |
4196 | goto out; | |
ef710e10 | 4197 | } |
12883efb | 4198 | #endif |
577b785f | 4199 | |
1c80025a | 4200 | if (t->init) { |
b6f11df2 | 4201 | ret = tracer_init(t, tr); |
1c80025a FW |
4202 | if (ret) |
4203 | goto out; | |
4204 | } | |
bc0c38d1 | 4205 | |
2b6080f2 | 4206 | tr->current_trace = t; |
50512ab5 | 4207 | tr->current_trace->enabled++; |
9f029e83 | 4208 | trace_branch_enable(tr); |
bc0c38d1 SR |
4209 | out: |
4210 | mutex_unlock(&trace_types_lock); | |
4211 | ||
d9e54076 PZ |
4212 | return ret; |
4213 | } | |
4214 | ||
4215 | static ssize_t | |
4216 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
4217 | size_t cnt, loff_t *ppos) | |
4218 | { | |
607e2ea1 | 4219 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 4220 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
4221 | int i; |
4222 | size_t ret; | |
e6e7a65a FW |
4223 | int err; |
4224 | ||
4225 | ret = cnt; | |
d9e54076 | 4226 | |
ee6c2c1b LZ |
4227 | if (cnt > MAX_TRACER_SIZE) |
4228 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
4229 | |
4230 | if (copy_from_user(&buf, ubuf, cnt)) | |
4231 | return -EFAULT; | |
4232 | ||
4233 | buf[cnt] = 0; | |
4234 | ||
4235 | /* strip ending whitespace. */ | |
4236 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
4237 | buf[i] = 0; | |
4238 | ||
607e2ea1 | 4239 | err = tracing_set_tracer(tr, buf); |
e6e7a65a FW |
4240 | if (err) |
4241 | return err; | |
d9e54076 | 4242 | |
cf8517cf | 4243 | *ppos += ret; |
bc0c38d1 | 4244 | |
c2931e05 | 4245 | return ret; |
bc0c38d1 SR |
4246 | } |
4247 | ||
4248 | static ssize_t | |
6508fa76 SF |
4249 | tracing_nsecs_read(unsigned long *ptr, char __user *ubuf, |
4250 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 4251 | { |
bc0c38d1 SR |
4252 | char buf[64]; |
4253 | int r; | |
4254 | ||
cffae437 | 4255 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 4256 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
4257 | if (r > sizeof(buf)) |
4258 | r = sizeof(buf); | |
4bf39a94 | 4259 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
4260 | } |
4261 | ||
4262 | static ssize_t | |
6508fa76 SF |
4263 | tracing_nsecs_write(unsigned long *ptr, const char __user *ubuf, |
4264 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 4265 | { |
5e39841c | 4266 | unsigned long val; |
c6caeeb1 | 4267 | int ret; |
bc0c38d1 | 4268 | |
22fe9b54 PH |
4269 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4270 | if (ret) | |
c6caeeb1 | 4271 | return ret; |
bc0c38d1 SR |
4272 | |
4273 | *ptr = val * 1000; | |
4274 | ||
4275 | return cnt; | |
4276 | } | |
4277 | ||
6508fa76 SF |
4278 | static ssize_t |
4279 | tracing_thresh_read(struct file *filp, char __user *ubuf, | |
4280 | size_t cnt, loff_t *ppos) | |
4281 | { | |
4282 | return tracing_nsecs_read(&tracing_thresh, ubuf, cnt, ppos); | |
4283 | } | |
4284 | ||
4285 | static ssize_t | |
4286 | tracing_thresh_write(struct file *filp, const char __user *ubuf, | |
4287 | size_t cnt, loff_t *ppos) | |
4288 | { | |
4289 | struct trace_array *tr = filp->private_data; | |
4290 | int ret; | |
4291 | ||
4292 | mutex_lock(&trace_types_lock); | |
4293 | ret = tracing_nsecs_write(&tracing_thresh, ubuf, cnt, ppos); | |
4294 | if (ret < 0) | |
4295 | goto out; | |
4296 | ||
4297 | if (tr->current_trace->update_thresh) { | |
4298 | ret = tr->current_trace->update_thresh(tr); | |
4299 | if (ret < 0) | |
4300 | goto out; | |
4301 | } | |
4302 | ||
4303 | ret = cnt; | |
4304 | out: | |
4305 | mutex_unlock(&trace_types_lock); | |
4306 | ||
4307 | return ret; | |
4308 | } | |
4309 | ||
4310 | static ssize_t | |
4311 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
4312 | size_t cnt, loff_t *ppos) | |
4313 | { | |
4314 | return tracing_nsecs_read(filp->private_data, ubuf, cnt, ppos); | |
4315 | } | |
4316 | ||
4317 | static ssize_t | |
4318 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
4319 | size_t cnt, loff_t *ppos) | |
4320 | { | |
4321 | return tracing_nsecs_write(filp->private_data, ubuf, cnt, ppos); | |
4322 | } | |
4323 | ||
b3806b43 SR |
4324 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
4325 | { | |
15544209 | 4326 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4327 | struct trace_iterator *iter; |
b04cc6b1 | 4328 | int ret = 0; |
b3806b43 SR |
4329 | |
4330 | if (tracing_disabled) | |
4331 | return -ENODEV; | |
4332 | ||
7b85af63 SRRH |
4333 | if (trace_array_get(tr) < 0) |
4334 | return -ENODEV; | |
4335 | ||
b04cc6b1 FW |
4336 | mutex_lock(&trace_types_lock); |
4337 | ||
b3806b43 SR |
4338 | /* create a buffer to store the information to pass to userspace */ |
4339 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
4340 | if (!iter) { |
4341 | ret = -ENOMEM; | |
f77d09a3 | 4342 | __trace_array_put(tr); |
b04cc6b1 FW |
4343 | goto out; |
4344 | } | |
b3806b43 | 4345 | |
3a161d99 | 4346 | trace_seq_init(&iter->seq); |
d716ff71 | 4347 | iter->trace = tr->current_trace; |
d7350c3f | 4348 | |
4462344e | 4349 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 4350 | ret = -ENOMEM; |
d7350c3f | 4351 | goto fail; |
4462344e RR |
4352 | } |
4353 | ||
a309720c | 4354 | /* trace pipe does not show start of buffer */ |
4462344e | 4355 | cpumask_setall(iter->started); |
a309720c | 4356 | |
112f38a7 SR |
4357 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
4358 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
4359 | ||
8be0709f | 4360 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 4361 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
4362 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
4363 | ||
15544209 ON |
4364 | iter->tr = tr; |
4365 | iter->trace_buffer = &tr->trace_buffer; | |
4366 | iter->cpu_file = tracing_get_cpu(inode); | |
d7350c3f | 4367 | mutex_init(&iter->mutex); |
b3806b43 SR |
4368 | filp->private_data = iter; |
4369 | ||
107bad8b SR |
4370 | if (iter->trace->pipe_open) |
4371 | iter->trace->pipe_open(iter); | |
107bad8b | 4372 | |
b444786f | 4373 | nonseekable_open(inode, filp); |
cf6ab6d9 SRRH |
4374 | |
4375 | tr->current_trace->ref++; | |
b04cc6b1 FW |
4376 | out: |
4377 | mutex_unlock(&trace_types_lock); | |
4378 | return ret; | |
d7350c3f FW |
4379 | |
4380 | fail: | |
4381 | kfree(iter->trace); | |
4382 | kfree(iter); | |
7b85af63 | 4383 | __trace_array_put(tr); |
d7350c3f FW |
4384 | mutex_unlock(&trace_types_lock); |
4385 | return ret; | |
b3806b43 SR |
4386 | } |
4387 | ||
4388 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
4389 | { | |
4390 | struct trace_iterator *iter = file->private_data; | |
15544209 | 4391 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4392 | |
b04cc6b1 FW |
4393 | mutex_lock(&trace_types_lock); |
4394 | ||
cf6ab6d9 SRRH |
4395 | tr->current_trace->ref--; |
4396 | ||
29bf4a5e | 4397 | if (iter->trace->pipe_close) |
c521efd1 SR |
4398 | iter->trace->pipe_close(iter); |
4399 | ||
b04cc6b1 FW |
4400 | mutex_unlock(&trace_types_lock); |
4401 | ||
4462344e | 4402 | free_cpumask_var(iter->started); |
d7350c3f | 4403 | mutex_destroy(&iter->mutex); |
b3806b43 | 4404 | kfree(iter); |
b3806b43 | 4405 | |
7b85af63 SRRH |
4406 | trace_array_put(tr); |
4407 | ||
b3806b43 SR |
4408 | return 0; |
4409 | } | |
4410 | ||
2a2cc8f7 | 4411 | static unsigned int |
cc60cdc9 | 4412 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 4413 | { |
15693458 SRRH |
4414 | /* Iterators are static, they should be filled or empty */ |
4415 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
4416 | return POLLIN | POLLRDNORM; | |
2a2cc8f7 | 4417 | |
15693458 | 4418 | if (trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
4419 | /* |
4420 | * Always select as readable when in blocking mode | |
4421 | */ | |
4422 | return POLLIN | POLLRDNORM; | |
15693458 | 4423 | else |
12883efb | 4424 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 4425 | filp, poll_table); |
2a2cc8f7 | 4426 | } |
2a2cc8f7 | 4427 | |
cc60cdc9 SR |
4428 | static unsigned int |
4429 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
4430 | { | |
4431 | struct trace_iterator *iter = filp->private_data; | |
4432 | ||
4433 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
4434 | } |
4435 | ||
d716ff71 | 4436 | /* Must be called with iter->mutex held. */ |
ff98781b | 4437 | static int tracing_wait_pipe(struct file *filp) |
b3806b43 SR |
4438 | { |
4439 | struct trace_iterator *iter = filp->private_data; | |
8b8b3683 | 4440 | int ret; |
b3806b43 | 4441 | |
b3806b43 | 4442 | while (trace_empty(iter)) { |
2dc8f095 | 4443 | |
107bad8b | 4444 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 4445 | return -EAGAIN; |
107bad8b | 4446 | } |
2dc8f095 | 4447 | |
b3806b43 | 4448 | /* |
250bfd3d | 4449 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
4450 | * We still block if tracing is disabled, but we have never |
4451 | * read anything. This allows a user to cat this file, and | |
4452 | * then enable tracing. But after we have read something, | |
4453 | * we give an EOF when tracing is again disabled. | |
4454 | * | |
4455 | * iter->pos will be 0 if we haven't read anything. | |
4456 | */ | |
10246fa3 | 4457 | if (!tracing_is_on() && iter->pos) |
b3806b43 | 4458 | break; |
f4874261 SRRH |
4459 | |
4460 | mutex_unlock(&iter->mutex); | |
4461 | ||
e30f53aa | 4462 | ret = wait_on_pipe(iter, false); |
f4874261 SRRH |
4463 | |
4464 | mutex_lock(&iter->mutex); | |
4465 | ||
8b8b3683 SRRH |
4466 | if (ret) |
4467 | return ret; | |
b3806b43 SR |
4468 | } |
4469 | ||
ff98781b EGM |
4470 | return 1; |
4471 | } | |
4472 | ||
4473 | /* | |
4474 | * Consumer reader. | |
4475 | */ | |
4476 | static ssize_t | |
4477 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
4478 | size_t cnt, loff_t *ppos) | |
4479 | { | |
4480 | struct trace_iterator *iter = filp->private_data; | |
4481 | ssize_t sret; | |
4482 | ||
4483 | /* return any leftover data */ | |
4484 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
4485 | if (sret != -EBUSY) | |
4486 | return sret; | |
4487 | ||
f9520750 | 4488 | trace_seq_init(&iter->seq); |
ff98781b | 4489 | |
d7350c3f FW |
4490 | /* |
4491 | * Avoid more than one consumer on a single file descriptor | |
4492 | * This is just a matter of traces coherency, the ring buffer itself | |
4493 | * is protected. | |
4494 | */ | |
4495 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
4496 | if (iter->trace->read) { |
4497 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
4498 | if (sret) | |
4499 | goto out; | |
4500 | } | |
4501 | ||
4502 | waitagain: | |
4503 | sret = tracing_wait_pipe(filp); | |
4504 | if (sret <= 0) | |
4505 | goto out; | |
4506 | ||
b3806b43 | 4507 | /* stop when tracing is finished */ |
ff98781b EGM |
4508 | if (trace_empty(iter)) { |
4509 | sret = 0; | |
107bad8b | 4510 | goto out; |
ff98781b | 4511 | } |
b3806b43 SR |
4512 | |
4513 | if (cnt >= PAGE_SIZE) | |
4514 | cnt = PAGE_SIZE - 1; | |
4515 | ||
53d0aa77 | 4516 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
4517 | memset(&iter->seq, 0, |
4518 | sizeof(struct trace_iterator) - | |
4519 | offsetof(struct trace_iterator, seq)); | |
ed5467da | 4520 | cpumask_clear(iter->started); |
4823ed7e | 4521 | iter->pos = -1; |
b3806b43 | 4522 | |
4f535968 | 4523 | trace_event_read_lock(); |
7e53bd42 | 4524 | trace_access_lock(iter->cpu_file); |
955b61e5 | 4525 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 4526 | enum print_line_t ret; |
5ac48378 | 4527 | int save_len = iter->seq.seq.len; |
088b1e42 | 4528 | |
f9896bf3 | 4529 | ret = print_trace_line(iter); |
2c4f035f | 4530 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 | 4531 | /* don't print partial lines */ |
5ac48378 | 4532 | iter->seq.seq.len = save_len; |
b3806b43 | 4533 | break; |
088b1e42 | 4534 | } |
b91facc3 FW |
4535 | if (ret != TRACE_TYPE_NO_CONSUME) |
4536 | trace_consume(iter); | |
b3806b43 | 4537 | |
5ac48378 | 4538 | if (trace_seq_used(&iter->seq) >= cnt) |
b3806b43 | 4539 | break; |
ee5e51f5 JO |
4540 | |
4541 | /* | |
4542 | * Setting the full flag means we reached the trace_seq buffer | |
4543 | * size and we should leave by partial output condition above. | |
4544 | * One of the trace_seq_* functions is not used properly. | |
4545 | */ | |
4546 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
4547 | iter->ent->type); | |
b3806b43 | 4548 | } |
7e53bd42 | 4549 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4550 | trace_event_read_unlock(); |
b3806b43 | 4551 | |
b3806b43 | 4552 | /* Now copy what we have to the user */ |
6c6c2796 | 4553 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
5ac48378 | 4554 | if (iter->seq.seq.readpos >= trace_seq_used(&iter->seq)) |
f9520750 | 4555 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
4556 | |
4557 | /* | |
25985edc | 4558 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
4559 | * entries, go back to wait for more entries. |
4560 | */ | |
6c6c2796 | 4561 | if (sret == -EBUSY) |
9ff4b974 | 4562 | goto waitagain; |
b3806b43 | 4563 | |
107bad8b | 4564 | out: |
d7350c3f | 4565 | mutex_unlock(&iter->mutex); |
107bad8b | 4566 | |
6c6c2796 | 4567 | return sret; |
b3806b43 SR |
4568 | } |
4569 | ||
3c56819b EGM |
4570 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, |
4571 | unsigned int idx) | |
4572 | { | |
4573 | __free_page(spd->pages[idx]); | |
4574 | } | |
4575 | ||
28dfef8f | 4576 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 | 4577 | .can_merge = 0, |
34cd4998 | 4578 | .confirm = generic_pipe_buf_confirm, |
92fdd98c | 4579 | .release = generic_pipe_buf_release, |
34cd4998 SR |
4580 | .steal = generic_pipe_buf_steal, |
4581 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
4582 | }; |
4583 | ||
34cd4998 | 4584 | static size_t |
fa7c7f6e | 4585 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
4586 | { |
4587 | size_t count; | |
74f06bb7 | 4588 | int save_len; |
34cd4998 SR |
4589 | int ret; |
4590 | ||
4591 | /* Seq buffer is page-sized, exactly what we need. */ | |
4592 | for (;;) { | |
74f06bb7 | 4593 | save_len = iter->seq.seq.len; |
34cd4998 | 4594 | ret = print_trace_line(iter); |
74f06bb7 SRRH |
4595 | |
4596 | if (trace_seq_has_overflowed(&iter->seq)) { | |
4597 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
4598 | break; |
4599 | } | |
74f06bb7 SRRH |
4600 | |
4601 | /* | |
4602 | * This should not be hit, because it should only | |
4603 | * be set if the iter->seq overflowed. But check it | |
4604 | * anyway to be safe. | |
4605 | */ | |
34cd4998 | 4606 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
74f06bb7 SRRH |
4607 | iter->seq.seq.len = save_len; |
4608 | break; | |
4609 | } | |
4610 | ||
5ac48378 | 4611 | count = trace_seq_used(&iter->seq) - save_len; |
74f06bb7 SRRH |
4612 | if (rem < count) { |
4613 | rem = 0; | |
4614 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
4615 | break; |
4616 | } | |
4617 | ||
74e7ff8c LJ |
4618 | if (ret != TRACE_TYPE_NO_CONSUME) |
4619 | trace_consume(iter); | |
34cd4998 | 4620 | rem -= count; |
955b61e5 | 4621 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
4622 | rem = 0; |
4623 | iter->ent = NULL; | |
4624 | break; | |
4625 | } | |
4626 | } | |
4627 | ||
4628 | return rem; | |
4629 | } | |
4630 | ||
3c56819b EGM |
4631 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
4632 | loff_t *ppos, | |
4633 | struct pipe_inode_info *pipe, | |
4634 | size_t len, | |
4635 | unsigned int flags) | |
4636 | { | |
35f3d14d JA |
4637 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
4638 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
4639 | struct trace_iterator *iter = filp->private_data; |
4640 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
4641 | .pages = pages_def, |
4642 | .partial = partial_def, | |
34cd4998 | 4643 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 4644 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
4645 | .flags = flags, |
4646 | .ops = &tracing_pipe_buf_ops, | |
4647 | .spd_release = tracing_spd_release_pipe, | |
3c56819b EGM |
4648 | }; |
4649 | ssize_t ret; | |
34cd4998 | 4650 | size_t rem; |
3c56819b EGM |
4651 | unsigned int i; |
4652 | ||
35f3d14d JA |
4653 | if (splice_grow_spd(pipe, &spd)) |
4654 | return -ENOMEM; | |
4655 | ||
d7350c3f | 4656 | mutex_lock(&iter->mutex); |
3c56819b EGM |
4657 | |
4658 | if (iter->trace->splice_read) { | |
4659 | ret = iter->trace->splice_read(iter, filp, | |
4660 | ppos, pipe, len, flags); | |
4661 | if (ret) | |
34cd4998 | 4662 | goto out_err; |
3c56819b EGM |
4663 | } |
4664 | ||
4665 | ret = tracing_wait_pipe(filp); | |
4666 | if (ret <= 0) | |
34cd4998 | 4667 | goto out_err; |
3c56819b | 4668 | |
955b61e5 | 4669 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 4670 | ret = -EFAULT; |
34cd4998 | 4671 | goto out_err; |
3c56819b EGM |
4672 | } |
4673 | ||
4f535968 | 4674 | trace_event_read_lock(); |
7e53bd42 | 4675 | trace_access_lock(iter->cpu_file); |
4f535968 | 4676 | |
3c56819b | 4677 | /* Fill as many pages as possible. */ |
a786c06d | 4678 | for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) { |
35f3d14d JA |
4679 | spd.pages[i] = alloc_page(GFP_KERNEL); |
4680 | if (!spd.pages[i]) | |
34cd4998 | 4681 | break; |
3c56819b | 4682 | |
fa7c7f6e | 4683 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
4684 | |
4685 | /* Copy the data into the page, so we can start over. */ | |
4686 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 4687 | page_address(spd.pages[i]), |
5ac48378 | 4688 | trace_seq_used(&iter->seq)); |
3c56819b | 4689 | if (ret < 0) { |
35f3d14d | 4690 | __free_page(spd.pages[i]); |
3c56819b EGM |
4691 | break; |
4692 | } | |
35f3d14d | 4693 | spd.partial[i].offset = 0; |
5ac48378 | 4694 | spd.partial[i].len = trace_seq_used(&iter->seq); |
3c56819b | 4695 | |
f9520750 | 4696 | trace_seq_init(&iter->seq); |
3c56819b EGM |
4697 | } |
4698 | ||
7e53bd42 | 4699 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4700 | trace_event_read_unlock(); |
d7350c3f | 4701 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
4702 | |
4703 | spd.nr_pages = i; | |
4704 | ||
35f3d14d JA |
4705 | ret = splice_to_pipe(pipe, &spd); |
4706 | out: | |
047fe360 | 4707 | splice_shrink_spd(&spd); |
35f3d14d | 4708 | return ret; |
3c56819b | 4709 | |
34cd4998 | 4710 | out_err: |
d7350c3f | 4711 | mutex_unlock(&iter->mutex); |
35f3d14d | 4712 | goto out; |
3c56819b EGM |
4713 | } |
4714 | ||
a98a3c3f SR |
4715 | static ssize_t |
4716 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
4717 | size_t cnt, loff_t *ppos) | |
4718 | { | |
0bc392ee ON |
4719 | struct inode *inode = file_inode(filp); |
4720 | struct trace_array *tr = inode->i_private; | |
4721 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
4722 | char buf[64]; |
4723 | int r = 0; | |
4724 | ssize_t ret; | |
a98a3c3f | 4725 | |
db526ca3 | 4726 | mutex_lock(&trace_types_lock); |
438ced17 | 4727 | |
0bc392ee | 4728 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
4729 | int cpu, buf_size_same; |
4730 | unsigned long size; | |
4731 | ||
4732 | size = 0; | |
4733 | buf_size_same = 1; | |
4734 | /* check if all cpu sizes are same */ | |
4735 | for_each_tracing_cpu(cpu) { | |
4736 | /* fill in the size from first enabled cpu */ | |
4737 | if (size == 0) | |
12883efb SRRH |
4738 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
4739 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
4740 | buf_size_same = 0; |
4741 | break; | |
4742 | } | |
4743 | } | |
4744 | ||
4745 | if (buf_size_same) { | |
4746 | if (!ring_buffer_expanded) | |
4747 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
4748 | size >> 10, | |
4749 | trace_buf_size >> 10); | |
4750 | else | |
4751 | r = sprintf(buf, "%lu\n", size >> 10); | |
4752 | } else | |
4753 | r = sprintf(buf, "X\n"); | |
4754 | } else | |
0bc392ee | 4755 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10); |
438ced17 | 4756 | |
db526ca3 SR |
4757 | mutex_unlock(&trace_types_lock); |
4758 | ||
438ced17 VN |
4759 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
4760 | return ret; | |
a98a3c3f SR |
4761 | } |
4762 | ||
4763 | static ssize_t | |
4764 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
4765 | size_t cnt, loff_t *ppos) | |
4766 | { | |
0bc392ee ON |
4767 | struct inode *inode = file_inode(filp); |
4768 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 4769 | unsigned long val; |
4f271a2a | 4770 | int ret; |
a98a3c3f | 4771 | |
22fe9b54 PH |
4772 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4773 | if (ret) | |
c6caeeb1 | 4774 | return ret; |
a98a3c3f SR |
4775 | |
4776 | /* must have at least 1 entry */ | |
4777 | if (!val) | |
4778 | return -EINVAL; | |
4779 | ||
1696b2b0 SR |
4780 | /* value is in KB */ |
4781 | val <<= 10; | |
0bc392ee | 4782 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
4783 | if (ret < 0) |
4784 | return ret; | |
a98a3c3f | 4785 | |
cf8517cf | 4786 | *ppos += cnt; |
a98a3c3f | 4787 | |
4f271a2a VN |
4788 | return cnt; |
4789 | } | |
bf5e6519 | 4790 | |
f81ab074 VN |
4791 | static ssize_t |
4792 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
4793 | size_t cnt, loff_t *ppos) | |
4794 | { | |
4795 | struct trace_array *tr = filp->private_data; | |
4796 | char buf[64]; | |
4797 | int r, cpu; | |
4798 | unsigned long size = 0, expanded_size = 0; | |
4799 | ||
4800 | mutex_lock(&trace_types_lock); | |
4801 | for_each_tracing_cpu(cpu) { | |
12883efb | 4802 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
4803 | if (!ring_buffer_expanded) |
4804 | expanded_size += trace_buf_size >> 10; | |
4805 | } | |
4806 | if (ring_buffer_expanded) | |
4807 | r = sprintf(buf, "%lu\n", size); | |
4808 | else | |
4809 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
4810 | mutex_unlock(&trace_types_lock); | |
4811 | ||
4812 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4813 | } | |
4814 | ||
4f271a2a VN |
4815 | static ssize_t |
4816 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
4817 | size_t cnt, loff_t *ppos) | |
4818 | { | |
4819 | /* | |
4820 | * There is no need to read what the user has written, this function | |
4821 | * is just to make sure that there is no error when "echo" is used | |
4822 | */ | |
4823 | ||
4824 | *ppos += cnt; | |
a98a3c3f SR |
4825 | |
4826 | return cnt; | |
4827 | } | |
4828 | ||
4f271a2a VN |
4829 | static int |
4830 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
4831 | { | |
2b6080f2 SR |
4832 | struct trace_array *tr = inode->i_private; |
4833 | ||
cf30cf67 SR |
4834 | /* disable tracing ? */ |
4835 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
711e1243 | 4836 | tracer_tracing_off(tr); |
4f271a2a | 4837 | /* resize the ring buffer to 0 */ |
2b6080f2 | 4838 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 4839 | |
7b85af63 SRRH |
4840 | trace_array_put(tr); |
4841 | ||
4f271a2a VN |
4842 | return 0; |
4843 | } | |
4844 | ||
5bf9a1ee PP |
4845 | static ssize_t |
4846 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
4847 | size_t cnt, loff_t *fpos) | |
4848 | { | |
d696b58c | 4849 | unsigned long addr = (unsigned long)ubuf; |
2d71619c | 4850 | struct trace_array *tr = filp->private_data; |
d696b58c SR |
4851 | struct ring_buffer_event *event; |
4852 | struct ring_buffer *buffer; | |
4853 | struct print_entry *entry; | |
4854 | unsigned long irq_flags; | |
4855 | struct page *pages[2]; | |
6edb2a8a | 4856 | void *map_page[2]; |
d696b58c SR |
4857 | int nr_pages = 1; |
4858 | ssize_t written; | |
d696b58c SR |
4859 | int offset; |
4860 | int size; | |
4861 | int len; | |
4862 | int ret; | |
6edb2a8a | 4863 | int i; |
5bf9a1ee | 4864 | |
c76f0694 | 4865 | if (tracing_disabled) |
5bf9a1ee PP |
4866 | return -EINVAL; |
4867 | ||
5224c3a3 MSB |
4868 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
4869 | return -EINVAL; | |
4870 | ||
5bf9a1ee PP |
4871 | if (cnt > TRACE_BUF_SIZE) |
4872 | cnt = TRACE_BUF_SIZE; | |
4873 | ||
d696b58c SR |
4874 | /* |
4875 | * Userspace is injecting traces into the kernel trace buffer. | |
4876 | * We want to be as non intrusive as possible. | |
4877 | * To do so, we do not want to allocate any special buffers | |
4878 | * or take any locks, but instead write the userspace data | |
4879 | * straight into the ring buffer. | |
4880 | * | |
4881 | * First we need to pin the userspace buffer into memory, | |
4882 | * which, most likely it is, because it just referenced it. | |
4883 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
4884 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
4885 | * pages directly. We then write the data directly into the | |
4886 | * ring buffer. | |
4887 | */ | |
4888 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 4889 | |
d696b58c SR |
4890 | /* check if we cross pages */ |
4891 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
4892 | nr_pages = 2; | |
4893 | ||
4894 | offset = addr & (PAGE_SIZE - 1); | |
4895 | addr &= PAGE_MASK; | |
4896 | ||
4897 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
4898 | if (ret < nr_pages) { | |
4899 | while (--ret >= 0) | |
4900 | put_page(pages[ret]); | |
4901 | written = -EFAULT; | |
4902 | goto out; | |
5bf9a1ee | 4903 | } |
d696b58c | 4904 | |
6edb2a8a SR |
4905 | for (i = 0; i < nr_pages; i++) |
4906 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
4907 | |
4908 | local_save_flags(irq_flags); | |
4909 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
2d71619c | 4910 | buffer = tr->trace_buffer.buffer; |
d696b58c SR |
4911 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
4912 | irq_flags, preempt_count()); | |
4913 | if (!event) { | |
4914 | /* Ring buffer disabled, return as if not open for write */ | |
4915 | written = -EBADF; | |
4916 | goto out_unlock; | |
5bf9a1ee | 4917 | } |
d696b58c SR |
4918 | |
4919 | entry = ring_buffer_event_data(event); | |
4920 | entry->ip = _THIS_IP_; | |
4921 | ||
4922 | if (nr_pages == 2) { | |
4923 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
4924 | memcpy(&entry->buf, map_page[0] + offset, len); |
4925 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 4926 | } else |
6edb2a8a | 4927 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 4928 | |
d696b58c SR |
4929 | if (entry->buf[cnt - 1] != '\n') { |
4930 | entry->buf[cnt] = '\n'; | |
4931 | entry->buf[cnt + 1] = '\0'; | |
4932 | } else | |
4933 | entry->buf[cnt] = '\0'; | |
4934 | ||
7ffbd48d | 4935 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 4936 | |
d696b58c | 4937 | written = cnt; |
5bf9a1ee | 4938 | |
d696b58c | 4939 | *fpos += written; |
1aa54bca | 4940 | |
d696b58c | 4941 | out_unlock: |
6edb2a8a SR |
4942 | for (i = 0; i < nr_pages; i++){ |
4943 | kunmap_atomic(map_page[i]); | |
4944 | put_page(pages[i]); | |
4945 | } | |
d696b58c | 4946 | out: |
1aa54bca | 4947 | return written; |
5bf9a1ee PP |
4948 | } |
4949 | ||
13f16d20 | 4950 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 4951 | { |
2b6080f2 | 4952 | struct trace_array *tr = m->private; |
5079f326 Z |
4953 | int i; |
4954 | ||
4955 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 4956 | seq_printf(m, |
5079f326 | 4957 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
4958 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
4959 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 4960 | seq_putc(m, '\n'); |
5079f326 | 4961 | |
13f16d20 | 4962 | return 0; |
5079f326 Z |
4963 | } |
4964 | ||
e1e232ca | 4965 | static int tracing_set_clock(struct trace_array *tr, const char *clockstr) |
5079f326 | 4966 | { |
5079f326 Z |
4967 | int i; |
4968 | ||
5079f326 Z |
4969 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { |
4970 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
4971 | break; | |
4972 | } | |
4973 | if (i == ARRAY_SIZE(trace_clocks)) | |
4974 | return -EINVAL; | |
4975 | ||
5079f326 Z |
4976 | mutex_lock(&trace_types_lock); |
4977 | ||
2b6080f2 SR |
4978 | tr->clock_id = i; |
4979 | ||
12883efb | 4980 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 4981 | |
60303ed3 DS |
4982 | /* |
4983 | * New clock may not be consistent with the previous clock. | |
4984 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
4985 | */ | |
9457158b | 4986 | tracing_reset_online_cpus(&tr->trace_buffer); |
12883efb SRRH |
4987 | |
4988 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4989 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) | |
4990 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); | |
9457158b | 4991 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 4992 | #endif |
60303ed3 | 4993 | |
5079f326 Z |
4994 | mutex_unlock(&trace_types_lock); |
4995 | ||
e1e232ca SR |
4996 | return 0; |
4997 | } | |
4998 | ||
4999 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
5000 | size_t cnt, loff_t *fpos) | |
5001 | { | |
5002 | struct seq_file *m = filp->private_data; | |
5003 | struct trace_array *tr = m->private; | |
5004 | char buf[64]; | |
5005 | const char *clockstr; | |
5006 | int ret; | |
5007 | ||
5008 | if (cnt >= sizeof(buf)) | |
5009 | return -EINVAL; | |
5010 | ||
5011 | if (copy_from_user(&buf, ubuf, cnt)) | |
5012 | return -EFAULT; | |
5013 | ||
5014 | buf[cnt] = 0; | |
5015 | ||
5016 | clockstr = strstrip(buf); | |
5017 | ||
5018 | ret = tracing_set_clock(tr, clockstr); | |
5019 | if (ret) | |
5020 | return ret; | |
5021 | ||
5079f326 Z |
5022 | *fpos += cnt; |
5023 | ||
5024 | return cnt; | |
5025 | } | |
5026 | ||
13f16d20 LZ |
5027 | static int tracing_clock_open(struct inode *inode, struct file *file) |
5028 | { | |
7b85af63 SRRH |
5029 | struct trace_array *tr = inode->i_private; |
5030 | int ret; | |
5031 | ||
13f16d20 LZ |
5032 | if (tracing_disabled) |
5033 | return -ENODEV; | |
2b6080f2 | 5034 | |
7b85af63 SRRH |
5035 | if (trace_array_get(tr)) |
5036 | return -ENODEV; | |
5037 | ||
5038 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
5039 | if (ret < 0) | |
5040 | trace_array_put(tr); | |
5041 | ||
5042 | return ret; | |
13f16d20 LZ |
5043 | } |
5044 | ||
6de58e62 SRRH |
5045 | struct ftrace_buffer_info { |
5046 | struct trace_iterator iter; | |
5047 | void *spare; | |
5048 | unsigned int read; | |
5049 | }; | |
5050 | ||
debdd57f HT |
5051 | #ifdef CONFIG_TRACER_SNAPSHOT |
5052 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
5053 | { | |
6484c71c | 5054 | struct trace_array *tr = inode->i_private; |
debdd57f | 5055 | struct trace_iterator *iter; |
2b6080f2 | 5056 | struct seq_file *m; |
debdd57f HT |
5057 | int ret = 0; |
5058 | ||
ff451961 SRRH |
5059 | if (trace_array_get(tr) < 0) |
5060 | return -ENODEV; | |
5061 | ||
debdd57f | 5062 | if (file->f_mode & FMODE_READ) { |
6484c71c | 5063 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
5064 | if (IS_ERR(iter)) |
5065 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
5066 | } else { |
5067 | /* Writes still need the seq_file to hold the private data */ | |
f77d09a3 | 5068 | ret = -ENOMEM; |
2b6080f2 SR |
5069 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
5070 | if (!m) | |
f77d09a3 | 5071 | goto out; |
2b6080f2 SR |
5072 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
5073 | if (!iter) { | |
5074 | kfree(m); | |
f77d09a3 | 5075 | goto out; |
2b6080f2 | 5076 | } |
f77d09a3 AL |
5077 | ret = 0; |
5078 | ||
ff451961 | 5079 | iter->tr = tr; |
6484c71c ON |
5080 | iter->trace_buffer = &tr->max_buffer; |
5081 | iter->cpu_file = tracing_get_cpu(inode); | |
2b6080f2 SR |
5082 | m->private = iter; |
5083 | file->private_data = m; | |
debdd57f | 5084 | } |
f77d09a3 | 5085 | out: |
ff451961 SRRH |
5086 | if (ret < 0) |
5087 | trace_array_put(tr); | |
5088 | ||
debdd57f HT |
5089 | return ret; |
5090 | } | |
5091 | ||
5092 | static ssize_t | |
5093 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5094 | loff_t *ppos) | |
5095 | { | |
2b6080f2 SR |
5096 | struct seq_file *m = filp->private_data; |
5097 | struct trace_iterator *iter = m->private; | |
5098 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
5099 | unsigned long val; |
5100 | int ret; | |
5101 | ||
5102 | ret = tracing_update_buffers(); | |
5103 | if (ret < 0) | |
5104 | return ret; | |
5105 | ||
5106 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5107 | if (ret) | |
5108 | return ret; | |
5109 | ||
5110 | mutex_lock(&trace_types_lock); | |
5111 | ||
2b6080f2 | 5112 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
5113 | ret = -EBUSY; |
5114 | goto out; | |
5115 | } | |
5116 | ||
5117 | switch (val) { | |
5118 | case 0: | |
f1affcaa SRRH |
5119 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
5120 | ret = -EINVAL; | |
5121 | break; | |
debdd57f | 5122 | } |
3209cff4 SRRH |
5123 | if (tr->allocated_snapshot) |
5124 | free_snapshot(tr); | |
debdd57f HT |
5125 | break; |
5126 | case 1: | |
f1affcaa SRRH |
5127 | /* Only allow per-cpu swap if the ring buffer supports it */ |
5128 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
5129 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
5130 | ret = -EINVAL; | |
5131 | break; | |
5132 | } | |
5133 | #endif | |
45ad21ca | 5134 | if (!tr->allocated_snapshot) { |
3209cff4 | 5135 | ret = alloc_snapshot(tr); |
debdd57f HT |
5136 | if (ret < 0) |
5137 | break; | |
debdd57f | 5138 | } |
debdd57f HT |
5139 | local_irq_disable(); |
5140 | /* Now, we're going to swap */ | |
f1affcaa | 5141 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 5142 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 5143 | else |
ce9bae55 | 5144 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
5145 | local_irq_enable(); |
5146 | break; | |
5147 | default: | |
45ad21ca | 5148 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
5149 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
5150 | tracing_reset_online_cpus(&tr->max_buffer); | |
5151 | else | |
5152 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
5153 | } | |
debdd57f HT |
5154 | break; |
5155 | } | |
5156 | ||
5157 | if (ret >= 0) { | |
5158 | *ppos += cnt; | |
5159 | ret = cnt; | |
5160 | } | |
5161 | out: | |
5162 | mutex_unlock(&trace_types_lock); | |
5163 | return ret; | |
5164 | } | |
2b6080f2 SR |
5165 | |
5166 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
5167 | { | |
5168 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
5169 | int ret; |
5170 | ||
5171 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
5172 | |
5173 | if (file->f_mode & FMODE_READ) | |
ff451961 | 5174 | return ret; |
2b6080f2 SR |
5175 | |
5176 | /* If write only, the seq_file is just a stub */ | |
5177 | if (m) | |
5178 | kfree(m->private); | |
5179 | kfree(m); | |
5180 | ||
5181 | return 0; | |
5182 | } | |
5183 | ||
6de58e62 SRRH |
5184 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
5185 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5186 | size_t count, loff_t *ppos); | |
5187 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
5188 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5189 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
5190 | ||
5191 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
5192 | { | |
5193 | struct ftrace_buffer_info *info; | |
5194 | int ret; | |
5195 | ||
5196 | ret = tracing_buffers_open(inode, filp); | |
5197 | if (ret < 0) | |
5198 | return ret; | |
5199 | ||
5200 | info = filp->private_data; | |
5201 | ||
5202 | if (info->iter.trace->use_max_tr) { | |
5203 | tracing_buffers_release(inode, filp); | |
5204 | return -EBUSY; | |
5205 | } | |
5206 | ||
5207 | info->iter.snapshot = true; | |
5208 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
5209 | ||
5210 | return ret; | |
5211 | } | |
5212 | ||
debdd57f HT |
5213 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5214 | ||
5215 | ||
6508fa76 SF |
5216 | static const struct file_operations tracing_thresh_fops = { |
5217 | .open = tracing_open_generic, | |
5218 | .read = tracing_thresh_read, | |
5219 | .write = tracing_thresh_write, | |
5220 | .llseek = generic_file_llseek, | |
5221 | }; | |
5222 | ||
5e2336a0 | 5223 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
5224 | .open = tracing_open_generic, |
5225 | .read = tracing_max_lat_read, | |
5226 | .write = tracing_max_lat_write, | |
b444786f | 5227 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5228 | }; |
5229 | ||
5e2336a0 | 5230 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
5231 | .open = tracing_open_generic, |
5232 | .read = tracing_set_trace_read, | |
5233 | .write = tracing_set_trace_write, | |
b444786f | 5234 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5235 | }; |
5236 | ||
5e2336a0 | 5237 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 5238 | .open = tracing_open_pipe, |
2a2cc8f7 | 5239 | .poll = tracing_poll_pipe, |
4bf39a94 | 5240 | .read = tracing_read_pipe, |
3c56819b | 5241 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 5242 | .release = tracing_release_pipe, |
b444786f | 5243 | .llseek = no_llseek, |
b3806b43 SR |
5244 | }; |
5245 | ||
5e2336a0 | 5246 | static const struct file_operations tracing_entries_fops = { |
0bc392ee | 5247 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
5248 | .read = tracing_entries_read, |
5249 | .write = tracing_entries_write, | |
b444786f | 5250 | .llseek = generic_file_llseek, |
0bc392ee | 5251 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
5252 | }; |
5253 | ||
f81ab074 | 5254 | static const struct file_operations tracing_total_entries_fops = { |
7b85af63 | 5255 | .open = tracing_open_generic_tr, |
f81ab074 VN |
5256 | .read = tracing_total_entries_read, |
5257 | .llseek = generic_file_llseek, | |
7b85af63 | 5258 | .release = tracing_release_generic_tr, |
f81ab074 VN |
5259 | }; |
5260 | ||
4f271a2a | 5261 | static const struct file_operations tracing_free_buffer_fops = { |
7b85af63 | 5262 | .open = tracing_open_generic_tr, |
4f271a2a VN |
5263 | .write = tracing_free_buffer_write, |
5264 | .release = tracing_free_buffer_release, | |
5265 | }; | |
5266 | ||
5e2336a0 | 5267 | static const struct file_operations tracing_mark_fops = { |
7b85af63 | 5268 | .open = tracing_open_generic_tr, |
5bf9a1ee | 5269 | .write = tracing_mark_write, |
b444786f | 5270 | .llseek = generic_file_llseek, |
7b85af63 | 5271 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
5272 | }; |
5273 | ||
5079f326 | 5274 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
5275 | .open = tracing_clock_open, |
5276 | .read = seq_read, | |
5277 | .llseek = seq_lseek, | |
7b85af63 | 5278 | .release = tracing_single_release_tr, |
5079f326 Z |
5279 | .write = tracing_clock_write, |
5280 | }; | |
5281 | ||
debdd57f HT |
5282 | #ifdef CONFIG_TRACER_SNAPSHOT |
5283 | static const struct file_operations snapshot_fops = { | |
5284 | .open = tracing_snapshot_open, | |
5285 | .read = seq_read, | |
5286 | .write = tracing_snapshot_write, | |
098c879e | 5287 | .llseek = tracing_lseek, |
2b6080f2 | 5288 | .release = tracing_snapshot_release, |
debdd57f | 5289 | }; |
debdd57f | 5290 | |
6de58e62 SRRH |
5291 | static const struct file_operations snapshot_raw_fops = { |
5292 | .open = snapshot_raw_open, | |
5293 | .read = tracing_buffers_read, | |
5294 | .release = tracing_buffers_release, | |
5295 | .splice_read = tracing_buffers_splice_read, | |
5296 | .llseek = no_llseek, | |
2cadf913 SR |
5297 | }; |
5298 | ||
6de58e62 SRRH |
5299 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5300 | ||
2cadf913 SR |
5301 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
5302 | { | |
46ef2be0 | 5303 | struct trace_array *tr = inode->i_private; |
2cadf913 | 5304 | struct ftrace_buffer_info *info; |
7b85af63 | 5305 | int ret; |
2cadf913 SR |
5306 | |
5307 | if (tracing_disabled) | |
5308 | return -ENODEV; | |
5309 | ||
7b85af63 SRRH |
5310 | if (trace_array_get(tr) < 0) |
5311 | return -ENODEV; | |
5312 | ||
2cadf913 | 5313 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
7b85af63 SRRH |
5314 | if (!info) { |
5315 | trace_array_put(tr); | |
2cadf913 | 5316 | return -ENOMEM; |
7b85af63 | 5317 | } |
2cadf913 | 5318 | |
a695cb58 SRRH |
5319 | mutex_lock(&trace_types_lock); |
5320 | ||
cc60cdc9 | 5321 | info->iter.tr = tr; |
46ef2be0 | 5322 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 5323 | info->iter.trace = tr->current_trace; |
12883efb | 5324 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 5325 | info->spare = NULL; |
2cadf913 | 5326 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 5327 | info->read = (unsigned int)-1; |
2cadf913 SR |
5328 | |
5329 | filp->private_data = info; | |
5330 | ||
cf6ab6d9 SRRH |
5331 | tr->current_trace->ref++; |
5332 | ||
a695cb58 SRRH |
5333 | mutex_unlock(&trace_types_lock); |
5334 | ||
7b85af63 SRRH |
5335 | ret = nonseekable_open(inode, filp); |
5336 | if (ret < 0) | |
5337 | trace_array_put(tr); | |
5338 | ||
5339 | return ret; | |
2cadf913 SR |
5340 | } |
5341 | ||
cc60cdc9 SR |
5342 | static unsigned int |
5343 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
5344 | { | |
5345 | struct ftrace_buffer_info *info = filp->private_data; | |
5346 | struct trace_iterator *iter = &info->iter; | |
5347 | ||
5348 | return trace_poll(iter, filp, poll_table); | |
5349 | } | |
5350 | ||
2cadf913 SR |
5351 | static ssize_t |
5352 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5353 | size_t count, loff_t *ppos) | |
5354 | { | |
5355 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 5356 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5357 | ssize_t ret; |
6de58e62 | 5358 | ssize_t size; |
2cadf913 | 5359 | |
2dc5d12b SR |
5360 | if (!count) |
5361 | return 0; | |
5362 | ||
6de58e62 | 5363 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
5364 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
5365 | return -EBUSY; | |
6de58e62 SRRH |
5366 | #endif |
5367 | ||
ddd538f3 | 5368 | if (!info->spare) |
12883efb SRRH |
5369 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
5370 | iter->cpu_file); | |
ddd538f3 | 5371 | if (!info->spare) |
d716ff71 | 5372 | return -ENOMEM; |
ddd538f3 | 5373 | |
2cadf913 SR |
5374 | /* Do we have previous read data to read? */ |
5375 | if (info->read < PAGE_SIZE) | |
5376 | goto read; | |
5377 | ||
b627344f | 5378 | again: |
cc60cdc9 | 5379 | trace_access_lock(iter->cpu_file); |
12883efb | 5380 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
5381 | &info->spare, |
5382 | count, | |
cc60cdc9 SR |
5383 | iter->cpu_file, 0); |
5384 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 5385 | |
b627344f SR |
5386 | if (ret < 0) { |
5387 | if (trace_empty(iter)) { | |
d716ff71 SRRH |
5388 | if ((filp->f_flags & O_NONBLOCK)) |
5389 | return -EAGAIN; | |
5390 | ||
e30f53aa | 5391 | ret = wait_on_pipe(iter, false); |
d716ff71 SRRH |
5392 | if (ret) |
5393 | return ret; | |
5394 | ||
b627344f SR |
5395 | goto again; |
5396 | } | |
d716ff71 | 5397 | return 0; |
b627344f | 5398 | } |
436fc280 | 5399 | |
436fc280 | 5400 | info->read = 0; |
b627344f | 5401 | read: |
2cadf913 SR |
5402 | size = PAGE_SIZE - info->read; |
5403 | if (size > count) | |
5404 | size = count; | |
5405 | ||
5406 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
d716ff71 SRRH |
5407 | if (ret == size) |
5408 | return -EFAULT; | |
5409 | ||
2dc5d12b SR |
5410 | size -= ret; |
5411 | ||
2cadf913 SR |
5412 | *ppos += size; |
5413 | info->read += size; | |
5414 | ||
5415 | return size; | |
5416 | } | |
5417 | ||
5418 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
5419 | { | |
5420 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5421 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5422 | |
a695cb58 SRRH |
5423 | mutex_lock(&trace_types_lock); |
5424 | ||
cf6ab6d9 SRRH |
5425 | iter->tr->current_trace->ref--; |
5426 | ||
ff451961 | 5427 | __trace_array_put(iter->tr); |
2cadf913 | 5428 | |
ddd538f3 | 5429 | if (info->spare) |
12883efb | 5430 | ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); |
2cadf913 SR |
5431 | kfree(info); |
5432 | ||
a695cb58 SRRH |
5433 | mutex_unlock(&trace_types_lock); |
5434 | ||
2cadf913 SR |
5435 | return 0; |
5436 | } | |
5437 | ||
5438 | struct buffer_ref { | |
5439 | struct ring_buffer *buffer; | |
5440 | void *page; | |
5441 | int ref; | |
5442 | }; | |
5443 | ||
5444 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
5445 | struct pipe_buffer *buf) | |
5446 | { | |
5447 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5448 | ||
5449 | if (--ref->ref) | |
5450 | return; | |
5451 | ||
5452 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5453 | kfree(ref); | |
5454 | buf->private = 0; | |
5455 | } | |
5456 | ||
2cadf913 SR |
5457 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
5458 | struct pipe_buffer *buf) | |
5459 | { | |
5460 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5461 | ||
5462 | ref->ref++; | |
5463 | } | |
5464 | ||
5465 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 5466 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 | 5467 | .can_merge = 0, |
2cadf913 SR |
5468 | .confirm = generic_pipe_buf_confirm, |
5469 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 5470 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
5471 | .get = buffer_pipe_buf_get, |
5472 | }; | |
5473 | ||
5474 | /* | |
5475 | * Callback from splice_to_pipe(), if we need to release some pages | |
5476 | * at the end of the spd in case we error'ed out in filling the pipe. | |
5477 | */ | |
5478 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
5479 | { | |
5480 | struct buffer_ref *ref = | |
5481 | (struct buffer_ref *)spd->partial[i].private; | |
5482 | ||
5483 | if (--ref->ref) | |
5484 | return; | |
5485 | ||
5486 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5487 | kfree(ref); | |
5488 | spd->partial[i].private = 0; | |
5489 | } | |
5490 | ||
5491 | static ssize_t | |
5492 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5493 | struct pipe_inode_info *pipe, size_t len, | |
5494 | unsigned int flags) | |
5495 | { | |
5496 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5497 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
5498 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
5499 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 5500 | struct splice_pipe_desc spd = { |
35f3d14d JA |
5501 | .pages = pages_def, |
5502 | .partial = partial_def, | |
047fe360 | 5503 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
5504 | .flags = flags, |
5505 | .ops = &buffer_pipe_buf_ops, | |
5506 | .spd_release = buffer_spd_release, | |
5507 | }; | |
5508 | struct buffer_ref *ref; | |
93459c6c | 5509 | int entries, size, i; |
07906da7 | 5510 | ssize_t ret = 0; |
2cadf913 | 5511 | |
6de58e62 | 5512 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
5513 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
5514 | return -EBUSY; | |
6de58e62 SRRH |
5515 | #endif |
5516 | ||
d716ff71 SRRH |
5517 | if (splice_grow_spd(pipe, &spd)) |
5518 | return -ENOMEM; | |
35f3d14d | 5519 | |
d716ff71 SRRH |
5520 | if (*ppos & (PAGE_SIZE - 1)) |
5521 | return -EINVAL; | |
93cfb3c9 LJ |
5522 | |
5523 | if (len & (PAGE_SIZE - 1)) { | |
d716ff71 SRRH |
5524 | if (len < PAGE_SIZE) |
5525 | return -EINVAL; | |
93cfb3c9 LJ |
5526 | len &= PAGE_MASK; |
5527 | } | |
5528 | ||
cc60cdc9 SR |
5529 | again: |
5530 | trace_access_lock(iter->cpu_file); | |
12883efb | 5531 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 5532 | |
a786c06d | 5533 | for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
5534 | struct page *page; |
5535 | int r; | |
5536 | ||
5537 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
07906da7 RV |
5538 | if (!ref) { |
5539 | ret = -ENOMEM; | |
2cadf913 | 5540 | break; |
07906da7 | 5541 | } |
2cadf913 | 5542 | |
7267fa68 | 5543 | ref->ref = 1; |
12883efb | 5544 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 5545 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
2cadf913 | 5546 | if (!ref->page) { |
07906da7 | 5547 | ret = -ENOMEM; |
2cadf913 SR |
5548 | kfree(ref); |
5549 | break; | |
5550 | } | |
5551 | ||
5552 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 5553 | len, iter->cpu_file, 1); |
2cadf913 | 5554 | if (r < 0) { |
7ea59064 | 5555 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
5556 | kfree(ref); |
5557 | break; | |
5558 | } | |
5559 | ||
5560 | /* | |
5561 | * zero out any left over data, this is going to | |
5562 | * user land. | |
5563 | */ | |
5564 | size = ring_buffer_page_len(ref->page); | |
5565 | if (size < PAGE_SIZE) | |
5566 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
5567 | ||
5568 | page = virt_to_page(ref->page); | |
5569 | ||
5570 | spd.pages[i] = page; | |
5571 | spd.partial[i].len = PAGE_SIZE; | |
5572 | spd.partial[i].offset = 0; | |
5573 | spd.partial[i].private = (unsigned long)ref; | |
5574 | spd.nr_pages++; | |
93cfb3c9 | 5575 | *ppos += PAGE_SIZE; |
93459c6c | 5576 | |
12883efb | 5577 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
5578 | } |
5579 | ||
cc60cdc9 | 5580 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
5581 | spd.nr_pages = i; |
5582 | ||
5583 | /* did we read anything? */ | |
5584 | if (!spd.nr_pages) { | |
07906da7 | 5585 | if (ret) |
d716ff71 SRRH |
5586 | return ret; |
5587 | ||
5588 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) | |
5589 | return -EAGAIN; | |
07906da7 | 5590 | |
e30f53aa | 5591 | ret = wait_on_pipe(iter, true); |
8b8b3683 | 5592 | if (ret) |
d716ff71 | 5593 | return ret; |
e30f53aa | 5594 | |
cc60cdc9 | 5595 | goto again; |
2cadf913 SR |
5596 | } |
5597 | ||
5598 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 5599 | splice_shrink_spd(&spd); |
6de58e62 | 5600 | |
2cadf913 SR |
5601 | return ret; |
5602 | } | |
5603 | ||
5604 | static const struct file_operations tracing_buffers_fops = { | |
5605 | .open = tracing_buffers_open, | |
5606 | .read = tracing_buffers_read, | |
cc60cdc9 | 5607 | .poll = tracing_buffers_poll, |
2cadf913 SR |
5608 | .release = tracing_buffers_release, |
5609 | .splice_read = tracing_buffers_splice_read, | |
5610 | .llseek = no_llseek, | |
5611 | }; | |
5612 | ||
c8d77183 SR |
5613 | static ssize_t |
5614 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
5615 | size_t count, loff_t *ppos) | |
5616 | { | |
4d3435b8 ON |
5617 | struct inode *inode = file_inode(filp); |
5618 | struct trace_array *tr = inode->i_private; | |
12883efb | 5619 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
4d3435b8 | 5620 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
5621 | struct trace_seq *s; |
5622 | unsigned long cnt; | |
c64e148a VN |
5623 | unsigned long long t; |
5624 | unsigned long usec_rem; | |
c8d77183 | 5625 | |
e4f2d10f | 5626 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 5627 | if (!s) |
a646365c | 5628 | return -ENOMEM; |
c8d77183 SR |
5629 | |
5630 | trace_seq_init(s); | |
5631 | ||
12883efb | 5632 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5633 | trace_seq_printf(s, "entries: %ld\n", cnt); |
5634 | ||
12883efb | 5635 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5636 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
5637 | ||
12883efb | 5638 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5639 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
5640 | ||
12883efb | 5641 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
5642 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
5643 | ||
58e8eedf | 5644 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 5645 | /* local or global for trace_clock */ |
12883efb | 5646 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
5647 | usec_rem = do_div(t, USEC_PER_SEC); |
5648 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
5649 | t, usec_rem); | |
5650 | ||
12883efb | 5651 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
5652 | usec_rem = do_div(t, USEC_PER_SEC); |
5653 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
5654 | } else { | |
5655 | /* counter or tsc mode for trace_clock */ | |
5656 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 5657 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 5658 | |
11043d8b | 5659 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 5660 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 5661 | } |
c64e148a | 5662 | |
12883efb | 5663 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
5664 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
5665 | ||
12883efb | 5666 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
5667 | trace_seq_printf(s, "read events: %ld\n", cnt); |
5668 | ||
5ac48378 SRRH |
5669 | count = simple_read_from_buffer(ubuf, count, ppos, |
5670 | s->buffer, trace_seq_used(s)); | |
c8d77183 SR |
5671 | |
5672 | kfree(s); | |
5673 | ||
5674 | return count; | |
5675 | } | |
5676 | ||
5677 | static const struct file_operations tracing_stats_fops = { | |
4d3435b8 | 5678 | .open = tracing_open_generic_tr, |
c8d77183 | 5679 | .read = tracing_stats_read, |
b444786f | 5680 | .llseek = generic_file_llseek, |
4d3435b8 | 5681 | .release = tracing_release_generic_tr, |
c8d77183 SR |
5682 | }; |
5683 | ||
bc0c38d1 SR |
5684 | #ifdef CONFIG_DYNAMIC_FTRACE |
5685 | ||
b807c3d0 SR |
5686 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
5687 | { | |
5688 | return 0; | |
5689 | } | |
5690 | ||
bc0c38d1 | 5691 | static ssize_t |
b807c3d0 | 5692 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
5693 | size_t cnt, loff_t *ppos) |
5694 | { | |
a26a2a27 SR |
5695 | static char ftrace_dyn_info_buffer[1024]; |
5696 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 5697 | unsigned long *p = filp->private_data; |
b807c3d0 | 5698 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 5699 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
5700 | int r; |
5701 | ||
b807c3d0 SR |
5702 | mutex_lock(&dyn_info_mutex); |
5703 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 5704 | |
a26a2a27 | 5705 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
5706 | buf[r++] = '\n'; |
5707 | ||
5708 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5709 | ||
5710 | mutex_unlock(&dyn_info_mutex); | |
5711 | ||
5712 | return r; | |
bc0c38d1 SR |
5713 | } |
5714 | ||
5e2336a0 | 5715 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 5716 | .open = tracing_open_generic, |
b807c3d0 | 5717 | .read = tracing_read_dyn_info, |
b444786f | 5718 | .llseek = generic_file_llseek, |
bc0c38d1 | 5719 | }; |
77fd5c15 | 5720 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 5721 | |
77fd5c15 SRRH |
5722 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
5723 | static void | |
5724 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
5725 | { | |
5726 | tracing_snapshot(); | |
5727 | } | |
bc0c38d1 | 5728 | |
77fd5c15 SRRH |
5729 | static void |
5730 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
bc0c38d1 | 5731 | { |
77fd5c15 SRRH |
5732 | unsigned long *count = (long *)data; |
5733 | ||
5734 | if (!*count) | |
5735 | return; | |
bc0c38d1 | 5736 | |
77fd5c15 SRRH |
5737 | if (*count != -1) |
5738 | (*count)--; | |
5739 | ||
5740 | tracing_snapshot(); | |
5741 | } | |
5742 | ||
5743 | static int | |
5744 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
5745 | struct ftrace_probe_ops *ops, void *data) | |
5746 | { | |
5747 | long count = (long)data; | |
5748 | ||
5749 | seq_printf(m, "%ps:", (void *)ip); | |
5750 | ||
fa6f0cc7 | 5751 | seq_puts(m, "snapshot"); |
77fd5c15 SRRH |
5752 | |
5753 | if (count == -1) | |
fa6f0cc7 | 5754 | seq_puts(m, ":unlimited\n"); |
77fd5c15 SRRH |
5755 | else |
5756 | seq_printf(m, ":count=%ld\n", count); | |
5757 | ||
5758 | return 0; | |
5759 | } | |
5760 | ||
5761 | static struct ftrace_probe_ops snapshot_probe_ops = { | |
5762 | .func = ftrace_snapshot, | |
5763 | .print = ftrace_snapshot_print, | |
5764 | }; | |
5765 | ||
5766 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
5767 | .func = ftrace_count_snapshot, | |
5768 | .print = ftrace_snapshot_print, | |
5769 | }; | |
5770 | ||
5771 | static int | |
5772 | ftrace_trace_snapshot_callback(struct ftrace_hash *hash, | |
5773 | char *glob, char *cmd, char *param, int enable) | |
5774 | { | |
5775 | struct ftrace_probe_ops *ops; | |
5776 | void *count = (void *)-1; | |
5777 | char *number; | |
5778 | int ret; | |
5779 | ||
5780 | /* hash funcs only work with set_ftrace_filter */ | |
5781 | if (!enable) | |
5782 | return -EINVAL; | |
5783 | ||
5784 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
5785 | ||
5786 | if (glob[0] == '!') { | |
5787 | unregister_ftrace_function_probe_func(glob+1, ops); | |
5788 | return 0; | |
5789 | } | |
5790 | ||
5791 | if (!param) | |
5792 | goto out_reg; | |
5793 | ||
5794 | number = strsep(¶m, ":"); | |
5795 | ||
5796 | if (!strlen(number)) | |
5797 | goto out_reg; | |
5798 | ||
5799 | /* | |
5800 | * We use the callback data field (which is a pointer) | |
5801 | * as our counter. | |
5802 | */ | |
5803 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
5804 | if (ret) | |
5805 | return ret; | |
5806 | ||
5807 | out_reg: | |
5808 | ret = register_ftrace_function_probe(glob, ops, count); | |
5809 | ||
5810 | if (ret >= 0) | |
5811 | alloc_snapshot(&global_trace); | |
5812 | ||
5813 | return ret < 0 ? ret : 0; | |
5814 | } | |
5815 | ||
5816 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
5817 | .name = "snapshot", | |
5818 | .func = ftrace_trace_snapshot_callback, | |
5819 | }; | |
5820 | ||
38de93ab | 5821 | static __init int register_snapshot_cmd(void) |
77fd5c15 SRRH |
5822 | { |
5823 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
5824 | } | |
5825 | #else | |
38de93ab | 5826 | static inline __init int register_snapshot_cmd(void) { return 0; } |
77fd5c15 | 5827 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ |
bc0c38d1 | 5828 | |
7eeafbca | 5829 | static struct dentry *tracing_get_dentry(struct trace_array *tr) |
bc0c38d1 | 5830 | { |
2b6080f2 | 5831 | return tr->dir; |
bc0c38d1 SR |
5832 | } |
5833 | ||
2b6080f2 | 5834 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 5835 | { |
b04cc6b1 FW |
5836 | struct dentry *d_tracer; |
5837 | ||
2b6080f2 SR |
5838 | if (tr->percpu_dir) |
5839 | return tr->percpu_dir; | |
b04cc6b1 | 5840 | |
7eeafbca | 5841 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 5842 | if (IS_ERR(d_tracer)) |
b04cc6b1 FW |
5843 | return NULL; |
5844 | ||
2b6080f2 | 5845 | tr->percpu_dir = debugfs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 5846 | |
2b6080f2 SR |
5847 | WARN_ONCE(!tr->percpu_dir, |
5848 | "Could not create debugfs directory 'per_cpu/%d'\n", cpu); | |
b04cc6b1 | 5849 | |
2b6080f2 | 5850 | return tr->percpu_dir; |
b04cc6b1 FW |
5851 | } |
5852 | ||
649e9c70 ON |
5853 | static struct dentry * |
5854 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
5855 | void *data, long cpu, const struct file_operations *fops) | |
5856 | { | |
5857 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
5858 | ||
5859 | if (ret) /* See tracing_get_cpu() */ | |
5860 | ret->d_inode->i_cdev = (void *)(cpu + 1); | |
5861 | return ret; | |
5862 | } | |
5863 | ||
2b6080f2 SR |
5864 | static void |
5865 | tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) | |
b04cc6b1 | 5866 | { |
2b6080f2 | 5867 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 5868 | struct dentry *d_cpu; |
dd49a38c | 5869 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 5870 | |
0a3d7ce7 NK |
5871 | if (!d_percpu) |
5872 | return; | |
5873 | ||
dd49a38c | 5874 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
5875 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
5876 | if (!d_cpu) { | |
5877 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
5878 | return; | |
5879 | } | |
b04cc6b1 | 5880 | |
8656e7a2 | 5881 | /* per cpu trace_pipe */ |
649e9c70 | 5882 | trace_create_cpu_file("trace_pipe", 0444, d_cpu, |
15544209 | 5883 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
5884 | |
5885 | /* per cpu trace */ | |
649e9c70 | 5886 | trace_create_cpu_file("trace", 0644, d_cpu, |
6484c71c | 5887 | tr, cpu, &tracing_fops); |
7f96f93f | 5888 | |
649e9c70 | 5889 | trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, |
46ef2be0 | 5890 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 5891 | |
649e9c70 | 5892 | trace_create_cpu_file("stats", 0444, d_cpu, |
4d3435b8 | 5893 | tr, cpu, &tracing_stats_fops); |
438ced17 | 5894 | |
649e9c70 | 5895 | trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, |
0bc392ee | 5896 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
5897 | |
5898 | #ifdef CONFIG_TRACER_SNAPSHOT | |
649e9c70 | 5899 | trace_create_cpu_file("snapshot", 0644, d_cpu, |
6484c71c | 5900 | tr, cpu, &snapshot_fops); |
6de58e62 | 5901 | |
649e9c70 | 5902 | trace_create_cpu_file("snapshot_raw", 0444, d_cpu, |
46ef2be0 | 5903 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 5904 | #endif |
b04cc6b1 FW |
5905 | } |
5906 | ||
60a11774 SR |
5907 | #ifdef CONFIG_FTRACE_SELFTEST |
5908 | /* Let selftest have access to static functions in this file */ | |
5909 | #include "trace_selftest.c" | |
5910 | #endif | |
5911 | ||
577b785f SR |
5912 | struct trace_option_dentry { |
5913 | struct tracer_opt *opt; | |
5914 | struct tracer_flags *flags; | |
2b6080f2 | 5915 | struct trace_array *tr; |
577b785f SR |
5916 | struct dentry *entry; |
5917 | }; | |
5918 | ||
5919 | static ssize_t | |
5920 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5921 | loff_t *ppos) | |
5922 | { | |
5923 | struct trace_option_dentry *topt = filp->private_data; | |
5924 | char *buf; | |
5925 | ||
5926 | if (topt->flags->val & topt->opt->bit) | |
5927 | buf = "1\n"; | |
5928 | else | |
5929 | buf = "0\n"; | |
5930 | ||
5931 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5932 | } | |
5933 | ||
5934 | static ssize_t | |
5935 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5936 | loff_t *ppos) | |
5937 | { | |
5938 | struct trace_option_dentry *topt = filp->private_data; | |
5939 | unsigned long val; | |
577b785f SR |
5940 | int ret; |
5941 | ||
22fe9b54 PH |
5942 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5943 | if (ret) | |
577b785f SR |
5944 | return ret; |
5945 | ||
8d18eaaf LZ |
5946 | if (val != 0 && val != 1) |
5947 | return -EINVAL; | |
577b785f | 5948 | |
8d18eaaf | 5949 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 5950 | mutex_lock(&trace_types_lock); |
8c1a49ae | 5951 | ret = __set_tracer_option(topt->tr, topt->flags, |
c757bea9 | 5952 | topt->opt, !val); |
577b785f SR |
5953 | mutex_unlock(&trace_types_lock); |
5954 | if (ret) | |
5955 | return ret; | |
577b785f SR |
5956 | } |
5957 | ||
5958 | *ppos += cnt; | |
5959 | ||
5960 | return cnt; | |
5961 | } | |
5962 | ||
5963 | ||
5964 | static const struct file_operations trace_options_fops = { | |
5965 | .open = tracing_open_generic, | |
5966 | .read = trace_options_read, | |
5967 | .write = trace_options_write, | |
b444786f | 5968 | .llseek = generic_file_llseek, |
577b785f SR |
5969 | }; |
5970 | ||
a8259075 SR |
5971 | static ssize_t |
5972 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
5973 | loff_t *ppos) | |
5974 | { | |
5975 | long index = (long)filp->private_data; | |
5976 | char *buf; | |
5977 | ||
5978 | if (trace_flags & (1 << index)) | |
5979 | buf = "1\n"; | |
5980 | else | |
5981 | buf = "0\n"; | |
5982 | ||
5983 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
5984 | } | |
5985 | ||
5986 | static ssize_t | |
5987 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5988 | loff_t *ppos) | |
5989 | { | |
2b6080f2 | 5990 | struct trace_array *tr = &global_trace; |
a8259075 | 5991 | long index = (long)filp->private_data; |
a8259075 SR |
5992 | unsigned long val; |
5993 | int ret; | |
5994 | ||
22fe9b54 PH |
5995 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5996 | if (ret) | |
a8259075 SR |
5997 | return ret; |
5998 | ||
f2d84b65 | 5999 | if (val != 0 && val != 1) |
a8259075 | 6000 | return -EINVAL; |
69d34da2 SRRH |
6001 | |
6002 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 6003 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 6004 | mutex_unlock(&trace_types_lock); |
a8259075 | 6005 | |
613f04a0 SRRH |
6006 | if (ret < 0) |
6007 | return ret; | |
6008 | ||
a8259075 SR |
6009 | *ppos += cnt; |
6010 | ||
6011 | return cnt; | |
6012 | } | |
6013 | ||
a8259075 SR |
6014 | static const struct file_operations trace_options_core_fops = { |
6015 | .open = tracing_open_generic, | |
6016 | .read = trace_options_core_read, | |
6017 | .write = trace_options_core_write, | |
b444786f | 6018 | .llseek = generic_file_llseek, |
a8259075 SR |
6019 | }; |
6020 | ||
5452af66 | 6021 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 6022 | umode_t mode, |
5452af66 FW |
6023 | struct dentry *parent, |
6024 | void *data, | |
6025 | const struct file_operations *fops) | |
6026 | { | |
6027 | struct dentry *ret; | |
6028 | ||
6029 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
6030 | if (!ret) | |
6031 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
6032 | ||
6033 | return ret; | |
6034 | } | |
6035 | ||
6036 | ||
2b6080f2 | 6037 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
6038 | { |
6039 | struct dentry *d_tracer; | |
a8259075 | 6040 | |
2b6080f2 SR |
6041 | if (tr->options) |
6042 | return tr->options; | |
a8259075 | 6043 | |
7eeafbca | 6044 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 6045 | if (IS_ERR(d_tracer)) |
a8259075 SR |
6046 | return NULL; |
6047 | ||
2b6080f2 SR |
6048 | tr->options = debugfs_create_dir("options", d_tracer); |
6049 | if (!tr->options) { | |
a8259075 SR |
6050 | pr_warning("Could not create debugfs directory 'options'\n"); |
6051 | return NULL; | |
6052 | } | |
6053 | ||
2b6080f2 | 6054 | return tr->options; |
a8259075 SR |
6055 | } |
6056 | ||
577b785f | 6057 | static void |
2b6080f2 SR |
6058 | create_trace_option_file(struct trace_array *tr, |
6059 | struct trace_option_dentry *topt, | |
577b785f SR |
6060 | struct tracer_flags *flags, |
6061 | struct tracer_opt *opt) | |
6062 | { | |
6063 | struct dentry *t_options; | |
577b785f | 6064 | |
2b6080f2 | 6065 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
6066 | if (!t_options) |
6067 | return; | |
6068 | ||
6069 | topt->flags = flags; | |
6070 | topt->opt = opt; | |
2b6080f2 | 6071 | topt->tr = tr; |
577b785f | 6072 | |
5452af66 | 6073 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
6074 | &trace_options_fops); |
6075 | ||
577b785f SR |
6076 | } |
6077 | ||
6078 | static struct trace_option_dentry * | |
2b6080f2 | 6079 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
6080 | { |
6081 | struct trace_option_dentry *topts; | |
6082 | struct tracer_flags *flags; | |
6083 | struct tracer_opt *opts; | |
6084 | int cnt; | |
6085 | ||
6086 | if (!tracer) | |
6087 | return NULL; | |
6088 | ||
6089 | flags = tracer->flags; | |
6090 | ||
6091 | if (!flags || !flags->opts) | |
6092 | return NULL; | |
6093 | ||
6094 | opts = flags->opts; | |
6095 | ||
6096 | for (cnt = 0; opts[cnt].name; cnt++) | |
6097 | ; | |
6098 | ||
0cfe8245 | 6099 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
6100 | if (!topts) |
6101 | return NULL; | |
6102 | ||
6103 | for (cnt = 0; opts[cnt].name; cnt++) | |
2b6080f2 | 6104 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f SR |
6105 | &opts[cnt]); |
6106 | ||
6107 | return topts; | |
6108 | } | |
6109 | ||
6110 | static void | |
6111 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
6112 | { | |
6113 | int cnt; | |
6114 | ||
6115 | if (!topts) | |
6116 | return; | |
6117 | ||
3f4d8f78 FF |
6118 | for (cnt = 0; topts[cnt].opt; cnt++) |
6119 | debugfs_remove(topts[cnt].entry); | |
577b785f SR |
6120 | |
6121 | kfree(topts); | |
6122 | } | |
6123 | ||
a8259075 | 6124 | static struct dentry * |
2b6080f2 SR |
6125 | create_trace_option_core_file(struct trace_array *tr, |
6126 | const char *option, long index) | |
a8259075 SR |
6127 | { |
6128 | struct dentry *t_options; | |
a8259075 | 6129 | |
2b6080f2 | 6130 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
6131 | if (!t_options) |
6132 | return NULL; | |
6133 | ||
5452af66 | 6134 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 6135 | &trace_options_core_fops); |
a8259075 SR |
6136 | } |
6137 | ||
2b6080f2 | 6138 | static __init void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
6139 | { |
6140 | struct dentry *t_options; | |
a8259075 SR |
6141 | int i; |
6142 | ||
2b6080f2 | 6143 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
6144 | if (!t_options) |
6145 | return; | |
6146 | ||
5452af66 | 6147 | for (i = 0; trace_options[i]; i++) |
2b6080f2 | 6148 | create_trace_option_core_file(tr, trace_options[i], i); |
a8259075 SR |
6149 | } |
6150 | ||
499e5470 SR |
6151 | static ssize_t |
6152 | rb_simple_read(struct file *filp, char __user *ubuf, | |
6153 | size_t cnt, loff_t *ppos) | |
6154 | { | |
348f0fc2 | 6155 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
6156 | char buf[64]; |
6157 | int r; | |
6158 | ||
10246fa3 | 6159 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
6160 | r = sprintf(buf, "%d\n", r); |
6161 | ||
6162 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
6163 | } | |
6164 | ||
6165 | static ssize_t | |
6166 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
6167 | size_t cnt, loff_t *ppos) | |
6168 | { | |
348f0fc2 | 6169 | struct trace_array *tr = filp->private_data; |
12883efb | 6170 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
6171 | unsigned long val; |
6172 | int ret; | |
6173 | ||
6174 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
6175 | if (ret) | |
6176 | return ret; | |
6177 | ||
6178 | if (buffer) { | |
2df8f8a6 SR |
6179 | mutex_lock(&trace_types_lock); |
6180 | if (val) { | |
10246fa3 | 6181 | tracer_tracing_on(tr); |
2b6080f2 SR |
6182 | if (tr->current_trace->start) |
6183 | tr->current_trace->start(tr); | |
2df8f8a6 | 6184 | } else { |
10246fa3 | 6185 | tracer_tracing_off(tr); |
2b6080f2 SR |
6186 | if (tr->current_trace->stop) |
6187 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
6188 | } |
6189 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
6190 | } |
6191 | ||
6192 | (*ppos)++; | |
6193 | ||
6194 | return cnt; | |
6195 | } | |
6196 | ||
6197 | static const struct file_operations rb_simple_fops = { | |
7b85af63 | 6198 | .open = tracing_open_generic_tr, |
499e5470 SR |
6199 | .read = rb_simple_read, |
6200 | .write = rb_simple_write, | |
7b85af63 | 6201 | .release = tracing_release_generic_tr, |
499e5470 SR |
6202 | .llseek = default_llseek, |
6203 | }; | |
6204 | ||
277ba044 SR |
6205 | struct dentry *trace_instance_dir; |
6206 | ||
6207 | static void | |
6208 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer); | |
6209 | ||
55034cd6 SRRH |
6210 | static int |
6211 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
6212 | { |
6213 | enum ring_buffer_flags rb_flags; | |
737223fb SRRH |
6214 | |
6215 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; | |
6216 | ||
dced341b SRRH |
6217 | buf->tr = tr; |
6218 | ||
55034cd6 SRRH |
6219 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
6220 | if (!buf->buffer) | |
6221 | return -ENOMEM; | |
737223fb | 6222 | |
55034cd6 SRRH |
6223 | buf->data = alloc_percpu(struct trace_array_cpu); |
6224 | if (!buf->data) { | |
6225 | ring_buffer_free(buf->buffer); | |
6226 | return -ENOMEM; | |
6227 | } | |
737223fb | 6228 | |
737223fb SRRH |
6229 | /* Allocate the first page for all buffers */ |
6230 | set_buffer_entries(&tr->trace_buffer, | |
6231 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
6232 | ||
55034cd6 SRRH |
6233 | return 0; |
6234 | } | |
737223fb | 6235 | |
55034cd6 SRRH |
6236 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
6237 | { | |
6238 | int ret; | |
737223fb | 6239 | |
55034cd6 SRRH |
6240 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
6241 | if (ret) | |
6242 | return ret; | |
737223fb | 6243 | |
55034cd6 SRRH |
6244 | #ifdef CONFIG_TRACER_MAX_TRACE |
6245 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
6246 | allocate_snapshot ? size : 1); | |
6247 | if (WARN_ON(ret)) { | |
737223fb | 6248 | ring_buffer_free(tr->trace_buffer.buffer); |
55034cd6 SRRH |
6249 | free_percpu(tr->trace_buffer.data); |
6250 | return -ENOMEM; | |
6251 | } | |
6252 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 6253 | |
55034cd6 SRRH |
6254 | /* |
6255 | * Only the top level trace array gets its snapshot allocated | |
6256 | * from the kernel command line. | |
6257 | */ | |
6258 | allocate_snapshot = false; | |
737223fb | 6259 | #endif |
55034cd6 | 6260 | return 0; |
737223fb SRRH |
6261 | } |
6262 | ||
f0b70cc4 SRRH |
6263 | static void free_trace_buffer(struct trace_buffer *buf) |
6264 | { | |
6265 | if (buf->buffer) { | |
6266 | ring_buffer_free(buf->buffer); | |
6267 | buf->buffer = NULL; | |
6268 | free_percpu(buf->data); | |
6269 | buf->data = NULL; | |
6270 | } | |
6271 | } | |
6272 | ||
23aaa3c1 SRRH |
6273 | static void free_trace_buffers(struct trace_array *tr) |
6274 | { | |
6275 | if (!tr) | |
6276 | return; | |
6277 | ||
f0b70cc4 | 6278 | free_trace_buffer(&tr->trace_buffer); |
23aaa3c1 SRRH |
6279 | |
6280 | #ifdef CONFIG_TRACER_MAX_TRACE | |
f0b70cc4 | 6281 | free_trace_buffer(&tr->max_buffer); |
23aaa3c1 SRRH |
6282 | #endif |
6283 | } | |
6284 | ||
737223fb SRRH |
6285 | static int new_instance_create(const char *name) |
6286 | { | |
277ba044 SR |
6287 | struct trace_array *tr; |
6288 | int ret; | |
277ba044 SR |
6289 | |
6290 | mutex_lock(&trace_types_lock); | |
6291 | ||
6292 | ret = -EEXIST; | |
6293 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6294 | if (tr->name && strcmp(tr->name, name) == 0) | |
6295 | goto out_unlock; | |
6296 | } | |
6297 | ||
6298 | ret = -ENOMEM; | |
6299 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
6300 | if (!tr) | |
6301 | goto out_unlock; | |
6302 | ||
6303 | tr->name = kstrdup(name, GFP_KERNEL); | |
6304 | if (!tr->name) | |
6305 | goto out_free_tr; | |
6306 | ||
ccfe9e42 AL |
6307 | if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) |
6308 | goto out_free_tr; | |
6309 | ||
6310 | cpumask_copy(tr->tracing_cpumask, cpu_all_mask); | |
6311 | ||
277ba044 SR |
6312 | raw_spin_lock_init(&tr->start_lock); |
6313 | ||
0b9b12c1 SRRH |
6314 | tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
6315 | ||
277ba044 SR |
6316 | tr->current_trace = &nop_trace; |
6317 | ||
6318 | INIT_LIST_HEAD(&tr->systems); | |
6319 | INIT_LIST_HEAD(&tr->events); | |
6320 | ||
737223fb | 6321 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
6322 | goto out_free_tr; |
6323 | ||
277ba044 SR |
6324 | tr->dir = debugfs_create_dir(name, trace_instance_dir); |
6325 | if (!tr->dir) | |
6326 | goto out_free_tr; | |
6327 | ||
6328 | ret = event_trace_add_tracer(tr->dir, tr); | |
609e85a7 AL |
6329 | if (ret) { |
6330 | debugfs_remove_recursive(tr->dir); | |
277ba044 | 6331 | goto out_free_tr; |
609e85a7 | 6332 | } |
277ba044 SR |
6333 | |
6334 | init_tracer_debugfs(tr, tr->dir); | |
6335 | ||
6336 | list_add(&tr->list, &ftrace_trace_arrays); | |
6337 | ||
6338 | mutex_unlock(&trace_types_lock); | |
6339 | ||
6340 | return 0; | |
6341 | ||
6342 | out_free_tr: | |
23aaa3c1 | 6343 | free_trace_buffers(tr); |
ccfe9e42 | 6344 | free_cpumask_var(tr->tracing_cpumask); |
277ba044 SR |
6345 | kfree(tr->name); |
6346 | kfree(tr); | |
6347 | ||
6348 | out_unlock: | |
6349 | mutex_unlock(&trace_types_lock); | |
6350 | ||
6351 | return ret; | |
6352 | ||
6353 | } | |
6354 | ||
0c8916c3 SR |
6355 | static int instance_delete(const char *name) |
6356 | { | |
6357 | struct trace_array *tr; | |
6358 | int found = 0; | |
6359 | int ret; | |
6360 | ||
6361 | mutex_lock(&trace_types_lock); | |
6362 | ||
6363 | ret = -ENODEV; | |
6364 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6365 | if (tr->name && strcmp(tr->name, name) == 0) { | |
6366 | found = 1; | |
6367 | break; | |
6368 | } | |
6369 | } | |
6370 | if (!found) | |
6371 | goto out_unlock; | |
6372 | ||
a695cb58 | 6373 | ret = -EBUSY; |
cf6ab6d9 | 6374 | if (tr->ref || (tr->current_trace && tr->current_trace->ref)) |
a695cb58 SRRH |
6375 | goto out_unlock; |
6376 | ||
0c8916c3 SR |
6377 | list_del(&tr->list); |
6378 | ||
6b450d25 | 6379 | tracing_set_nop(tr); |
0c8916c3 | 6380 | event_trace_del_tracer(tr); |
591dffda | 6381 | ftrace_destroy_function_files(tr); |
0c8916c3 | 6382 | debugfs_remove_recursive(tr->dir); |
a9fcaaac | 6383 | free_trace_buffers(tr); |
0c8916c3 SR |
6384 | |
6385 | kfree(tr->name); | |
6386 | kfree(tr); | |
6387 | ||
6388 | ret = 0; | |
6389 | ||
6390 | out_unlock: | |
6391 | mutex_unlock(&trace_types_lock); | |
6392 | ||
6393 | return ret; | |
6394 | } | |
6395 | ||
277ba044 SR |
6396 | static int instance_mkdir (struct inode *inode, struct dentry *dentry, umode_t mode) |
6397 | { | |
6398 | struct dentry *parent; | |
6399 | int ret; | |
6400 | ||
6401 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
946e51f2 | 6402 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_u.d_alias); |
277ba044 SR |
6403 | if (WARN_ON_ONCE(parent != trace_instance_dir)) |
6404 | return -ENOENT; | |
6405 | ||
6406 | /* | |
6407 | * The inode mutex is locked, but debugfs_create_dir() will also | |
6408 | * take the mutex. As the instances directory can not be destroyed | |
6409 | * or changed in any other way, it is safe to unlock it, and | |
6410 | * let the dentry try. If two users try to make the same dir at | |
6411 | * the same time, then the new_instance_create() will determine the | |
6412 | * winner. | |
6413 | */ | |
6414 | mutex_unlock(&inode->i_mutex); | |
6415 | ||
6416 | ret = new_instance_create(dentry->d_iname); | |
6417 | ||
6418 | mutex_lock(&inode->i_mutex); | |
6419 | ||
6420 | return ret; | |
6421 | } | |
6422 | ||
0c8916c3 SR |
6423 | static int instance_rmdir(struct inode *inode, struct dentry *dentry) |
6424 | { | |
6425 | struct dentry *parent; | |
6426 | int ret; | |
6427 | ||
6428 | /* Paranoid: Make sure the parent is the "instances" directory */ | |
946e51f2 | 6429 | parent = hlist_entry(inode->i_dentry.first, struct dentry, d_u.d_alias); |
0c8916c3 SR |
6430 | if (WARN_ON_ONCE(parent != trace_instance_dir)) |
6431 | return -ENOENT; | |
6432 | ||
6433 | /* The caller did a dget() on dentry */ | |
6434 | mutex_unlock(&dentry->d_inode->i_mutex); | |
6435 | ||
6436 | /* | |
6437 | * The inode mutex is locked, but debugfs_create_dir() will also | |
6438 | * take the mutex. As the instances directory can not be destroyed | |
6439 | * or changed in any other way, it is safe to unlock it, and | |
6440 | * let the dentry try. If two users try to make the same dir at | |
6441 | * the same time, then the instance_delete() will determine the | |
6442 | * winner. | |
6443 | */ | |
6444 | mutex_unlock(&inode->i_mutex); | |
6445 | ||
6446 | ret = instance_delete(dentry->d_iname); | |
6447 | ||
6448 | mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT); | |
6449 | mutex_lock(&dentry->d_inode->i_mutex); | |
6450 | ||
6451 | return ret; | |
6452 | } | |
6453 | ||
277ba044 SR |
6454 | static const struct inode_operations instance_dir_inode_operations = { |
6455 | .lookup = simple_lookup, | |
6456 | .mkdir = instance_mkdir, | |
0c8916c3 | 6457 | .rmdir = instance_rmdir, |
277ba044 SR |
6458 | }; |
6459 | ||
6460 | static __init void create_trace_instances(struct dentry *d_tracer) | |
6461 | { | |
6462 | trace_instance_dir = debugfs_create_dir("instances", d_tracer); | |
6463 | if (WARN_ON(!trace_instance_dir)) | |
6464 | return; | |
6465 | ||
6466 | /* Hijack the dir inode operations, to allow mkdir */ | |
6467 | trace_instance_dir->d_inode->i_op = &instance_dir_inode_operations; | |
6468 | } | |
6469 | ||
2b6080f2 SR |
6470 | static void |
6471 | init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) | |
6472 | { | |
121aaee7 | 6473 | int cpu; |
2b6080f2 | 6474 | |
607e2ea1 SRRH |
6475 | trace_create_file("available_tracers", 0444, d_tracer, |
6476 | tr, &show_traces_fops); | |
6477 | ||
6478 | trace_create_file("current_tracer", 0644, d_tracer, | |
6479 | tr, &set_tracer_fops); | |
6480 | ||
ccfe9e42 AL |
6481 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
6482 | tr, &tracing_cpumask_fops); | |
6483 | ||
2b6080f2 SR |
6484 | trace_create_file("trace_options", 0644, d_tracer, |
6485 | tr, &tracing_iter_fops); | |
6486 | ||
6487 | trace_create_file("trace", 0644, d_tracer, | |
6484c71c | 6488 | tr, &tracing_fops); |
2b6080f2 SR |
6489 | |
6490 | trace_create_file("trace_pipe", 0444, d_tracer, | |
15544209 | 6491 | tr, &tracing_pipe_fops); |
2b6080f2 SR |
6492 | |
6493 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
0bc392ee | 6494 | tr, &tracing_entries_fops); |
2b6080f2 SR |
6495 | |
6496 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
6497 | tr, &tracing_total_entries_fops); | |
6498 | ||
238ae93d | 6499 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
6500 | tr, &tracing_free_buffer_fops); |
6501 | ||
6502 | trace_create_file("trace_marker", 0220, d_tracer, | |
6503 | tr, &tracing_mark_fops); | |
6504 | ||
6505 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
6506 | &trace_clock_fops); | |
6507 | ||
6508 | trace_create_file("tracing_on", 0644, d_tracer, | |
6484c71c | 6509 | tr, &rb_simple_fops); |
ce9bae55 | 6510 | |
6d9b3fa5 SRRH |
6511 | #ifdef CONFIG_TRACER_MAX_TRACE |
6512 | trace_create_file("tracing_max_latency", 0644, d_tracer, | |
6513 | &tr->max_latency, &tracing_max_lat_fops); | |
6514 | #endif | |
6515 | ||
591dffda SRRH |
6516 | if (ftrace_create_function_files(tr, d_tracer)) |
6517 | WARN(1, "Could not allocate function filter files"); | |
6518 | ||
ce9bae55 SRRH |
6519 | #ifdef CONFIG_TRACER_SNAPSHOT |
6520 | trace_create_file("snapshot", 0644, d_tracer, | |
6484c71c | 6521 | tr, &snapshot_fops); |
ce9bae55 | 6522 | #endif |
121aaee7 SRRH |
6523 | |
6524 | for_each_tracing_cpu(cpu) | |
6525 | tracing_init_debugfs_percpu(tr, cpu); | |
6526 | ||
2b6080f2 SR |
6527 | } |
6528 | ||
7eeafbca SRRH |
6529 | /** |
6530 | * tracing_init_dentry - initialize top level trace array | |
6531 | * | |
6532 | * This is called when creating files or directories in the tracing | |
6533 | * directory. It is called via fs_initcall() by any of the boot up code | |
6534 | * and expects to return the dentry of the top level tracing directory. | |
6535 | */ | |
6536 | struct dentry *tracing_init_dentry(void) | |
6537 | { | |
6538 | struct trace_array *tr = &global_trace; | |
6539 | ||
6540 | if (tr->dir) | |
6541 | return tr->dir; | |
6542 | ||
6543 | if (WARN_ON(!debugfs_initialized())) | |
6544 | return ERR_PTR(-ENODEV); | |
6545 | ||
6546 | tr->dir = debugfs_create_dir("tracing", NULL); | |
6547 | ||
6548 | if (!tr->dir) { | |
6549 | pr_warn_once("Could not create debugfs directory 'tracing'\n"); | |
6550 | return ERR_PTR(-ENOMEM); | |
6551 | } | |
6552 | ||
6553 | return tr->dir; | |
6554 | } | |
6555 | ||
b5ad384e | 6556 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
6557 | { |
6558 | struct dentry *d_tracer; | |
bc0c38d1 | 6559 | |
7e53bd42 LJ |
6560 | trace_access_lock_init(); |
6561 | ||
bc0c38d1 | 6562 | d_tracer = tracing_init_dentry(); |
14a5ae40 | 6563 | if (IS_ERR(d_tracer)) |
ed6f1c99 | 6564 | return 0; |
bc0c38d1 | 6565 | |
2b6080f2 | 6566 | init_tracer_debugfs(&global_trace, d_tracer); |
bc0c38d1 | 6567 | |
5452af66 | 6568 | trace_create_file("tracing_thresh", 0644, d_tracer, |
6508fa76 | 6569 | &global_trace, &tracing_thresh_fops); |
a8259075 | 6570 | |
339ae5d3 | 6571 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
6572 | NULL, &tracing_readme_fops); |
6573 | ||
69abe6a5 AP |
6574 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
6575 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 6576 | |
939c7a4f YY |
6577 | trace_create_file("saved_cmdlines_size", 0644, d_tracer, |
6578 | NULL, &tracing_saved_cmdlines_size_fops); | |
6579 | ||
bc0c38d1 | 6580 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
6581 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
6582 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 6583 | #endif |
b04cc6b1 | 6584 | |
277ba044 | 6585 | create_trace_instances(d_tracer); |
5452af66 | 6586 | |
2b6080f2 | 6587 | create_trace_options_dir(&global_trace); |
b04cc6b1 | 6588 | |
09d23a1d SRRH |
6589 | /* If the tracer was started via cmdline, create options for it here */ |
6590 | if (global_trace.current_trace != &nop_trace) | |
6591 | update_tracer_options(&global_trace, global_trace.current_trace); | |
6592 | ||
b5ad384e | 6593 | return 0; |
bc0c38d1 SR |
6594 | } |
6595 | ||
3f5a54e3 SR |
6596 | static int trace_panic_handler(struct notifier_block *this, |
6597 | unsigned long event, void *unused) | |
6598 | { | |
944ac425 | 6599 | if (ftrace_dump_on_oops) |
cecbca96 | 6600 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6601 | return NOTIFY_OK; |
6602 | } | |
6603 | ||
6604 | static struct notifier_block trace_panic_notifier = { | |
6605 | .notifier_call = trace_panic_handler, | |
6606 | .next = NULL, | |
6607 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
6608 | }; | |
6609 | ||
6610 | static int trace_die_handler(struct notifier_block *self, | |
6611 | unsigned long val, | |
6612 | void *data) | |
6613 | { | |
6614 | switch (val) { | |
6615 | case DIE_OOPS: | |
944ac425 | 6616 | if (ftrace_dump_on_oops) |
cecbca96 | 6617 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6618 | break; |
6619 | default: | |
6620 | break; | |
6621 | } | |
6622 | return NOTIFY_OK; | |
6623 | } | |
6624 | ||
6625 | static struct notifier_block trace_die_notifier = { | |
6626 | .notifier_call = trace_die_handler, | |
6627 | .priority = 200 | |
6628 | }; | |
6629 | ||
6630 | /* | |
6631 | * printk is set to max of 1024, we really don't need it that big. | |
6632 | * Nothing should be printing 1000 characters anyway. | |
6633 | */ | |
6634 | #define TRACE_MAX_PRINT 1000 | |
6635 | ||
6636 | /* | |
6637 | * Define here KERN_TRACE so that we have one place to modify | |
6638 | * it if we decide to change what log level the ftrace dump | |
6639 | * should be at. | |
6640 | */ | |
428aee14 | 6641 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 6642 | |
955b61e5 | 6643 | void |
3f5a54e3 SR |
6644 | trace_printk_seq(struct trace_seq *s) |
6645 | { | |
6646 | /* Probably should print a warning here. */ | |
3a161d99 SRRH |
6647 | if (s->seq.len >= TRACE_MAX_PRINT) |
6648 | s->seq.len = TRACE_MAX_PRINT; | |
3f5a54e3 | 6649 | |
820b75f6 SRRH |
6650 | /* |
6651 | * More paranoid code. Although the buffer size is set to | |
6652 | * PAGE_SIZE, and TRACE_MAX_PRINT is 1000, this is just | |
6653 | * an extra layer of protection. | |
6654 | */ | |
6655 | if (WARN_ON_ONCE(s->seq.len >= s->seq.size)) | |
6656 | s->seq.len = s->seq.size - 1; | |
3f5a54e3 SR |
6657 | |
6658 | /* should be zero ended, but we are paranoid. */ | |
3a161d99 | 6659 | s->buffer[s->seq.len] = 0; |
3f5a54e3 SR |
6660 | |
6661 | printk(KERN_TRACE "%s", s->buffer); | |
6662 | ||
f9520750 | 6663 | trace_seq_init(s); |
3f5a54e3 SR |
6664 | } |
6665 | ||
955b61e5 JW |
6666 | void trace_init_global_iter(struct trace_iterator *iter) |
6667 | { | |
6668 | iter->tr = &global_trace; | |
2b6080f2 | 6669 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 6670 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 6671 | iter->trace_buffer = &global_trace.trace_buffer; |
b2f974d6 CS |
6672 | |
6673 | if (iter->trace && iter->trace->open) | |
6674 | iter->trace->open(iter); | |
6675 | ||
6676 | /* Annotate start of buffers if we had overruns */ | |
6677 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) | |
6678 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
6679 | ||
6680 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ | |
6681 | if (trace_clocks[iter->tr->clock_id].in_ns) | |
6682 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
955b61e5 JW |
6683 | } |
6684 | ||
7fe70b57 | 6685 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 6686 | { |
3f5a54e3 SR |
6687 | /* use static because iter can be a bit big for the stack */ |
6688 | static struct trace_iterator iter; | |
7fe70b57 | 6689 | static atomic_t dump_running; |
cf586b61 | 6690 | unsigned int old_userobj; |
d769041f SR |
6691 | unsigned long flags; |
6692 | int cnt = 0, cpu; | |
3f5a54e3 | 6693 | |
7fe70b57 SRRH |
6694 | /* Only allow one dump user at a time. */ |
6695 | if (atomic_inc_return(&dump_running) != 1) { | |
6696 | atomic_dec(&dump_running); | |
6697 | return; | |
6698 | } | |
3f5a54e3 | 6699 | |
7fe70b57 SRRH |
6700 | /* |
6701 | * Always turn off tracing when we dump. | |
6702 | * We don't need to show trace output of what happens | |
6703 | * between multiple crashes. | |
6704 | * | |
6705 | * If the user does a sysrq-z, then they can re-enable | |
6706 | * tracing with echo 1 > tracing_on. | |
6707 | */ | |
0ee6b6cf | 6708 | tracing_off(); |
cf586b61 | 6709 | |
7fe70b57 | 6710 | local_irq_save(flags); |
3f5a54e3 | 6711 | |
38dbe0b1 | 6712 | /* Simulate the iterator */ |
955b61e5 JW |
6713 | trace_init_global_iter(&iter); |
6714 | ||
d769041f | 6715 | for_each_tracing_cpu(cpu) { |
12883efb | 6716 | atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled); |
d769041f SR |
6717 | } |
6718 | ||
cf586b61 FW |
6719 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
6720 | ||
b54d3de9 TE |
6721 | /* don't look at user memory in panic mode */ |
6722 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
6723 | ||
cecbca96 FW |
6724 | switch (oops_dump_mode) { |
6725 | case DUMP_ALL: | |
ae3b5093 | 6726 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6727 | break; |
6728 | case DUMP_ORIG: | |
6729 | iter.cpu_file = raw_smp_processor_id(); | |
6730 | break; | |
6731 | case DUMP_NONE: | |
6732 | goto out_enable; | |
6733 | default: | |
6734 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 6735 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
6736 | } |
6737 | ||
6738 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 6739 | |
7fe70b57 SRRH |
6740 | /* Did function tracer already get disabled? */ |
6741 | if (ftrace_is_dead()) { | |
6742 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
6743 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
6744 | } | |
6745 | ||
3f5a54e3 SR |
6746 | /* |
6747 | * We need to stop all tracing on all CPUS to read the | |
6748 | * the next buffer. This is a bit expensive, but is | |
6749 | * not done often. We fill all what we can read, | |
6750 | * and then release the locks again. | |
6751 | */ | |
6752 | ||
3f5a54e3 SR |
6753 | while (!trace_empty(&iter)) { |
6754 | ||
6755 | if (!cnt) | |
6756 | printk(KERN_TRACE "---------------------------------\n"); | |
6757 | ||
6758 | cnt++; | |
6759 | ||
6760 | /* reset all but tr, trace, and overruns */ | |
6761 | memset(&iter.seq, 0, | |
6762 | sizeof(struct trace_iterator) - | |
6763 | offsetof(struct trace_iterator, seq)); | |
6764 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
6765 | iter.pos = -1; | |
6766 | ||
955b61e5 | 6767 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
6768 | int ret; |
6769 | ||
6770 | ret = print_trace_line(&iter); | |
6771 | if (ret != TRACE_TYPE_NO_CONSUME) | |
6772 | trace_consume(&iter); | |
3f5a54e3 | 6773 | } |
b892e5c8 | 6774 | touch_nmi_watchdog(); |
3f5a54e3 SR |
6775 | |
6776 | trace_printk_seq(&iter.seq); | |
6777 | } | |
6778 | ||
6779 | if (!cnt) | |
6780 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
6781 | else | |
6782 | printk(KERN_TRACE "---------------------------------\n"); | |
6783 | ||
cecbca96 | 6784 | out_enable: |
7fe70b57 | 6785 | trace_flags |= old_userobj; |
cf586b61 | 6786 | |
7fe70b57 SRRH |
6787 | for_each_tracing_cpu(cpu) { |
6788 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); | |
cf586b61 | 6789 | } |
7fe70b57 | 6790 | atomic_dec(&dump_running); |
cd891ae0 | 6791 | local_irq_restore(flags); |
3f5a54e3 | 6792 | } |
a8eecf22 | 6793 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 6794 | |
3928a8a2 | 6795 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 6796 | { |
73c5162a | 6797 | int ring_buf_size; |
9e01c1b7 | 6798 | int ret = -ENOMEM; |
4c11d7ae | 6799 | |
9e01c1b7 RR |
6800 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
6801 | goto out; | |
6802 | ||
ccfe9e42 | 6803 | if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) |
9e01c1b7 | 6804 | goto out_free_buffer_mask; |
4c11d7ae | 6805 | |
07d777fe SR |
6806 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
6807 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 6808 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
6809 | trace_printk_init_buffers(); |
6810 | ||
73c5162a SR |
6811 | /* To save memory, keep the ring buffer size to its minimum */ |
6812 | if (ring_buffer_expanded) | |
6813 | ring_buf_size = trace_buf_size; | |
6814 | else | |
6815 | ring_buf_size = 1; | |
6816 | ||
9e01c1b7 | 6817 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
ccfe9e42 | 6818 | cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); |
9e01c1b7 | 6819 | |
2b6080f2 SR |
6820 | raw_spin_lock_init(&global_trace.start_lock); |
6821 | ||
2c4a33ab SRRH |
6822 | /* Used for event triggers */ |
6823 | temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); | |
6824 | if (!temp_buffer) | |
6825 | goto out_free_cpumask; | |
6826 | ||
939c7a4f YY |
6827 | if (trace_create_savedcmd() < 0) |
6828 | goto out_free_temp_buffer; | |
6829 | ||
9e01c1b7 | 6830 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 6831 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
6832 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
6833 | WARN_ON(1); | |
939c7a4f | 6834 | goto out_free_savedcmd; |
4c11d7ae | 6835 | } |
a7603ff4 | 6836 | |
499e5470 SR |
6837 | if (global_trace.buffer_disabled) |
6838 | tracing_off(); | |
4c11d7ae | 6839 | |
e1e232ca SR |
6840 | if (trace_boot_clock) { |
6841 | ret = tracing_set_clock(&global_trace, trace_boot_clock); | |
6842 | if (ret < 0) | |
6843 | pr_warning("Trace clock %s not defined, going back to default\n", | |
6844 | trace_boot_clock); | |
6845 | } | |
6846 | ||
ca164318 SRRH |
6847 | /* |
6848 | * register_tracer() might reference current_trace, so it | |
6849 | * needs to be set before we register anything. This is | |
6850 | * just a bootstrap of current_trace anyway. | |
6851 | */ | |
2b6080f2 SR |
6852 | global_trace.current_trace = &nop_trace; |
6853 | ||
0b9b12c1 SRRH |
6854 | global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
6855 | ||
4104d326 SRRH |
6856 | ftrace_init_global_array_ops(&global_trace); |
6857 | ||
ca164318 SRRH |
6858 | register_tracer(&nop_trace); |
6859 | ||
60a11774 SR |
6860 | /* All seems OK, enable tracing */ |
6861 | tracing_disabled = 0; | |
3928a8a2 | 6862 | |
3f5a54e3 SR |
6863 | atomic_notifier_chain_register(&panic_notifier_list, |
6864 | &trace_panic_notifier); | |
6865 | ||
6866 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 6867 | |
ae63b31e SR |
6868 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
6869 | ||
6870 | INIT_LIST_HEAD(&global_trace.systems); | |
6871 | INIT_LIST_HEAD(&global_trace.events); | |
6872 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
6873 | ||
7bcfaf54 SR |
6874 | while (trace_boot_options) { |
6875 | char *option; | |
6876 | ||
6877 | option = strsep(&trace_boot_options, ","); | |
2b6080f2 | 6878 | trace_set_options(&global_trace, option); |
7bcfaf54 SR |
6879 | } |
6880 | ||
77fd5c15 SRRH |
6881 | register_snapshot_cmd(); |
6882 | ||
2fc1dfbe | 6883 | return 0; |
3f5a54e3 | 6884 | |
939c7a4f YY |
6885 | out_free_savedcmd: |
6886 | free_saved_cmdlines_buffer(savedcmd); | |
2c4a33ab SRRH |
6887 | out_free_temp_buffer: |
6888 | ring_buffer_free(temp_buffer); | |
9e01c1b7 | 6889 | out_free_cpumask: |
ccfe9e42 | 6890 | free_cpumask_var(global_trace.tracing_cpumask); |
9e01c1b7 RR |
6891 | out_free_buffer_mask: |
6892 | free_cpumask_var(tracing_buffer_mask); | |
6893 | out: | |
6894 | return ret; | |
bc0c38d1 | 6895 | } |
b2821ae6 | 6896 | |
5f893b26 SRRH |
6897 | void __init trace_init(void) |
6898 | { | |
0daa2302 SRRH |
6899 | if (tracepoint_printk) { |
6900 | tracepoint_print_iter = | |
6901 | kmalloc(sizeof(*tracepoint_print_iter), GFP_KERNEL); | |
6902 | if (WARN_ON(!tracepoint_print_iter)) | |
6903 | tracepoint_printk = 0; | |
6904 | } | |
5f893b26 | 6905 | tracer_alloc_buffers(); |
5f893b26 SRRH |
6906 | trace_event_init(); |
6907 | } | |
6908 | ||
b2821ae6 SR |
6909 | __init static int clear_boot_tracer(void) |
6910 | { | |
6911 | /* | |
6912 | * The default tracer at boot buffer is an init section. | |
6913 | * This function is called in lateinit. If we did not | |
6914 | * find the boot tracer, then clear it out, to prevent | |
6915 | * later registration from accessing the buffer that is | |
6916 | * about to be freed. | |
6917 | */ | |
6918 | if (!default_bootup_tracer) | |
6919 | return 0; | |
6920 | ||
6921 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
6922 | default_bootup_tracer); | |
6923 | default_bootup_tracer = NULL; | |
6924 | ||
6925 | return 0; | |
6926 | } | |
6927 | ||
b5ad384e | 6928 | fs_initcall(tracer_init_debugfs); |
b2821ae6 | 6929 | late_initcall(clear_boot_tracer); |