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> |
8434dc93 | 23 | #include <linux/tracefs.h> |
4c11d7ae | 24 | #include <linux/pagemap.h> |
bc0c38d1 SR |
25 | #include <linux/hardirq.h> |
26 | #include <linux/linkage.h> | |
27 | #include <linux/uaccess.h> | |
2cadf913 | 28 | #include <linux/kprobes.h> |
bc0c38d1 SR |
29 | #include <linux/ftrace.h> |
30 | #include <linux/module.h> | |
31 | #include <linux/percpu.h> | |
2cadf913 | 32 | #include <linux/splice.h> |
3f5a54e3 | 33 | #include <linux/kdebug.h> |
5f0c6c03 | 34 | #include <linux/string.h> |
f76180bc | 35 | #include <linux/mount.h> |
7e53bd42 | 36 | #include <linux/rwsem.h> |
5a0e3ad6 | 37 | #include <linux/slab.h> |
bc0c38d1 SR |
38 | #include <linux/ctype.h> |
39 | #include <linux/init.h> | |
2a2cc8f7 | 40 | #include <linux/poll.h> |
b892e5c8 | 41 | #include <linux/nmi.h> |
bc0c38d1 | 42 | #include <linux/fs.h> |
8bd75c77 | 43 | #include <linux/sched/rt.h> |
86387f7e | 44 | |
bc0c38d1 | 45 | #include "trace.h" |
f0868d1e | 46 | #include "trace_output.h" |
bc0c38d1 | 47 | |
73c5162a SR |
48 | /* |
49 | * On boot up, the ring buffer is set to the minimum size, so that | |
50 | * we do not waste memory on systems that are not using tracing. | |
51 | */ | |
55034cd6 | 52 | bool ring_buffer_expanded; |
73c5162a | 53 | |
8e1b82e0 FW |
54 | /* |
55 | * We need to change this state when a selftest is running. | |
ff32504f FW |
56 | * A selftest will lurk into the ring-buffer to count the |
57 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 58 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
59 | * at the same time, giving false positive or negative results. |
60 | */ | |
8e1b82e0 | 61 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 62 | |
b2821ae6 SR |
63 | /* |
64 | * If a tracer is running, we do not want to run SELFTEST. | |
65 | */ | |
020e5f85 | 66 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 67 | |
0daa2302 SRRH |
68 | /* Pipe tracepoints to printk */ |
69 | struct trace_iterator *tracepoint_print_iter; | |
70 | int tracepoint_printk; | |
71 | ||
adf9f195 FW |
72 | /* For tracers that don't implement custom flags */ |
73 | static struct tracer_opt dummy_tracer_opt[] = { | |
74 | { } | |
75 | }; | |
76 | ||
77 | static struct tracer_flags dummy_tracer_flags = { | |
78 | .val = 0, | |
79 | .opts = dummy_tracer_opt | |
80 | }; | |
81 | ||
8c1a49ae SRRH |
82 | static int |
83 | dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) | |
adf9f195 FW |
84 | { |
85 | return 0; | |
86 | } | |
0f048701 | 87 | |
7ffbd48d SR |
88 | /* |
89 | * To prevent the comm cache from being overwritten when no | |
90 | * tracing is active, only save the comm when a trace event | |
91 | * occurred. | |
92 | */ | |
93 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
94 | ||
0f048701 SR |
95 | /* |
96 | * Kill all tracing for good (never come back). | |
97 | * It is initialized to 1 but will turn to zero if the initialization | |
98 | * of the tracer is successful. But that is the only place that sets | |
99 | * this back to zero. | |
100 | */ | |
4fd27358 | 101 | static int tracing_disabled = 1; |
0f048701 | 102 | |
9288f99a | 103 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f | 104 | |
955b61e5 | 105 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 106 | |
944ac425 SR |
107 | /* |
108 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
109 | * | |
110 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
111 | * is set, then ftrace_dump is called. This will output the contents | |
112 | * of the ftrace buffers to the console. This is very useful for | |
113 | * capturing traces that lead to crashes and outputing it to a | |
114 | * serial console. | |
115 | * | |
116 | * It is default off, but you can enable it with either specifying | |
117 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
118 | * /proc/sys/kernel/ftrace_dump_on_oops |
119 | * Set 1 if you want to dump buffers of all CPUs | |
120 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 121 | */ |
cecbca96 FW |
122 | |
123 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 124 | |
de7edd31 SRRH |
125 | /* When set, tracing will stop when a WARN*() is hit */ |
126 | int __disable_trace_on_warning; | |
127 | ||
9828413d SRRH |
128 | #ifdef CONFIG_TRACE_ENUM_MAP_FILE |
129 | /* Map of enums to their values, for "enum_map" file */ | |
130 | struct trace_enum_map_head { | |
131 | struct module *mod; | |
132 | unsigned long length; | |
133 | }; | |
134 | ||
135 | union trace_enum_map_item; | |
136 | ||
137 | struct trace_enum_map_tail { | |
138 | /* | |
139 | * "end" is first and points to NULL as it must be different | |
140 | * than "mod" or "enum_string" | |
141 | */ | |
142 | union trace_enum_map_item *next; | |
143 | const char *end; /* points to NULL */ | |
144 | }; | |
145 | ||
146 | static DEFINE_MUTEX(trace_enum_mutex); | |
147 | ||
148 | /* | |
149 | * The trace_enum_maps are saved in an array with two extra elements, | |
150 | * one at the beginning, and one at the end. The beginning item contains | |
151 | * the count of the saved maps (head.length), and the module they | |
152 | * belong to if not built in (head.mod). The ending item contains a | |
153 | * pointer to the next array of saved enum_map items. | |
154 | */ | |
155 | union trace_enum_map_item { | |
156 | struct trace_enum_map map; | |
157 | struct trace_enum_map_head head; | |
158 | struct trace_enum_map_tail tail; | |
159 | }; | |
160 | ||
161 | static union trace_enum_map_item *trace_enum_maps; | |
162 | #endif /* CONFIG_TRACE_ENUM_MAP_FILE */ | |
163 | ||
607e2ea1 | 164 | static int tracing_set_tracer(struct trace_array *tr, const char *buf); |
b2821ae6 | 165 | |
ee6c2c1b LZ |
166 | #define MAX_TRACER_SIZE 100 |
167 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 168 | static char *default_bootup_tracer; |
d9e54076 | 169 | |
55034cd6 SRRH |
170 | static bool allocate_snapshot; |
171 | ||
1beee96b | 172 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 173 | { |
67012ab1 | 174 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 175 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 176 | /* We are using ftrace early, expand it */ |
55034cd6 | 177 | ring_buffer_expanded = true; |
d9e54076 PZ |
178 | return 1; |
179 | } | |
1beee96b | 180 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 181 | |
944ac425 SR |
182 | static int __init set_ftrace_dump_on_oops(char *str) |
183 | { | |
cecbca96 FW |
184 | if (*str++ != '=' || !*str) { |
185 | ftrace_dump_on_oops = DUMP_ALL; | |
186 | return 1; | |
187 | } | |
188 | ||
189 | if (!strcmp("orig_cpu", str)) { | |
190 | ftrace_dump_on_oops = DUMP_ORIG; | |
191 | return 1; | |
192 | } | |
193 | ||
194 | return 0; | |
944ac425 SR |
195 | } |
196 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 197 | |
de7edd31 SRRH |
198 | static int __init stop_trace_on_warning(char *str) |
199 | { | |
933ff9f2 LCG |
200 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) |
201 | __disable_trace_on_warning = 1; | |
de7edd31 SRRH |
202 | return 1; |
203 | } | |
933ff9f2 | 204 | __setup("traceoff_on_warning", stop_trace_on_warning); |
de7edd31 | 205 | |
3209cff4 | 206 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
207 | { |
208 | allocate_snapshot = true; | |
209 | /* We also need the main ring buffer expanded */ | |
210 | ring_buffer_expanded = true; | |
211 | return 1; | |
212 | } | |
3209cff4 | 213 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 214 | |
7bcfaf54 SR |
215 | |
216 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
217 | static char *trace_boot_options __initdata; | |
218 | ||
219 | static int __init set_trace_boot_options(char *str) | |
220 | { | |
67012ab1 | 221 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
222 | trace_boot_options = trace_boot_options_buf; |
223 | return 0; | |
224 | } | |
225 | __setup("trace_options=", set_trace_boot_options); | |
226 | ||
e1e232ca SR |
227 | static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; |
228 | static char *trace_boot_clock __initdata; | |
229 | ||
230 | static int __init set_trace_boot_clock(char *str) | |
231 | { | |
232 | strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); | |
233 | trace_boot_clock = trace_boot_clock_buf; | |
234 | return 0; | |
235 | } | |
236 | __setup("trace_clock=", set_trace_boot_clock); | |
237 | ||
0daa2302 SRRH |
238 | static int __init set_tracepoint_printk(char *str) |
239 | { | |
240 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) | |
241 | tracepoint_printk = 1; | |
242 | return 1; | |
243 | } | |
244 | __setup("tp_printk", set_tracepoint_printk); | |
de7edd31 | 245 | |
cf8e3474 | 246 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
247 | { |
248 | nsec += 500; | |
249 | do_div(nsec, 1000); | |
250 | return nsec; | |
251 | } | |
252 | ||
4fcdae83 SR |
253 | /* |
254 | * The global_trace is the descriptor that holds the tracing | |
255 | * buffers for the live tracing. For each CPU, it contains | |
256 | * a link list of pages that will store trace entries. The | |
257 | * page descriptor of the pages in the memory is used to hold | |
258 | * the link list by linking the lru item in the page descriptor | |
259 | * to each of the pages in the buffer per CPU. | |
260 | * | |
261 | * For each active CPU there is a data field that holds the | |
262 | * pages for the buffer for that CPU. Each CPU has the same number | |
263 | * of pages allocated for its buffer. | |
264 | */ | |
bc0c38d1 SR |
265 | static struct trace_array global_trace; |
266 | ||
ae63b31e | 267 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 268 | |
ff451961 SRRH |
269 | int trace_array_get(struct trace_array *this_tr) |
270 | { | |
271 | struct trace_array *tr; | |
272 | int ret = -ENODEV; | |
273 | ||
274 | mutex_lock(&trace_types_lock); | |
275 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
276 | if (tr == this_tr) { | |
277 | tr->ref++; | |
278 | ret = 0; | |
279 | break; | |
280 | } | |
281 | } | |
282 | mutex_unlock(&trace_types_lock); | |
283 | ||
284 | return ret; | |
285 | } | |
286 | ||
287 | static void __trace_array_put(struct trace_array *this_tr) | |
288 | { | |
289 | WARN_ON(!this_tr->ref); | |
290 | this_tr->ref--; | |
291 | } | |
292 | ||
293 | void trace_array_put(struct trace_array *this_tr) | |
294 | { | |
295 | mutex_lock(&trace_types_lock); | |
296 | __trace_array_put(this_tr); | |
297 | mutex_unlock(&trace_types_lock); | |
298 | } | |
299 | ||
f306cc82 TZ |
300 | int filter_check_discard(struct ftrace_event_file *file, void *rec, |
301 | struct ring_buffer *buffer, | |
302 | struct ring_buffer_event *event) | |
eb02ce01 | 303 | { |
f306cc82 TZ |
304 | if (unlikely(file->flags & FTRACE_EVENT_FL_FILTERED) && |
305 | !filter_match_preds(file->filter, rec)) { | |
306 | ring_buffer_discard_commit(buffer, event); | |
307 | return 1; | |
308 | } | |
309 | ||
310 | return 0; | |
311 | } | |
312 | EXPORT_SYMBOL_GPL(filter_check_discard); | |
313 | ||
314 | int call_filter_check_discard(struct ftrace_event_call *call, void *rec, | |
315 | struct ring_buffer *buffer, | |
316 | struct ring_buffer_event *event) | |
317 | { | |
318 | if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && | |
319 | !filter_match_preds(call->filter, rec)) { | |
320 | ring_buffer_discard_commit(buffer, event); | |
321 | return 1; | |
322 | } | |
323 | ||
324 | return 0; | |
eb02ce01 | 325 | } |
f306cc82 | 326 | EXPORT_SYMBOL_GPL(call_filter_check_discard); |
eb02ce01 | 327 | |
ad1438a0 | 328 | static cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) |
37886f6a SR |
329 | { |
330 | u64 ts; | |
331 | ||
332 | /* Early boot up does not have a buffer yet */ | |
9457158b | 333 | if (!buf->buffer) |
37886f6a SR |
334 | return trace_clock_local(); |
335 | ||
9457158b AL |
336 | ts = ring_buffer_time_stamp(buf->buffer, cpu); |
337 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); | |
37886f6a SR |
338 | |
339 | return ts; | |
340 | } | |
bc0c38d1 | 341 | |
9457158b AL |
342 | cycle_t ftrace_now(int cpu) |
343 | { | |
344 | return buffer_ftrace_now(&global_trace.trace_buffer, cpu); | |
345 | } | |
346 | ||
10246fa3 SRRH |
347 | /** |
348 | * tracing_is_enabled - Show if global_trace has been disabled | |
349 | * | |
350 | * Shows if the global trace has been enabled or not. It uses the | |
351 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
352 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
353 | * need to know the accurate state, use tracing_is_on() which is a little | |
354 | * slower, but accurate. | |
355 | */ | |
9036990d SR |
356 | int tracing_is_enabled(void) |
357 | { | |
10246fa3 SRRH |
358 | /* |
359 | * For quick access (irqsoff uses this in fast path), just | |
360 | * return the mirror variable of the state of the ring buffer. | |
361 | * It's a little racy, but we don't really care. | |
362 | */ | |
363 | smp_rmb(); | |
364 | return !global_trace.buffer_disabled; | |
9036990d SR |
365 | } |
366 | ||
4fcdae83 | 367 | /* |
3928a8a2 SR |
368 | * trace_buf_size is the size in bytes that is allocated |
369 | * for a buffer. Note, the number of bytes is always rounded | |
370 | * to page size. | |
3f5a54e3 SR |
371 | * |
372 | * This number is purposely set to a low number of 16384. | |
373 | * If the dump on oops happens, it will be much appreciated | |
374 | * to not have to wait for all that output. Anyway this can be | |
375 | * boot time and run time configurable. | |
4fcdae83 | 376 | */ |
3928a8a2 | 377 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 378 | |
3928a8a2 | 379 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 380 | |
4fcdae83 | 381 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 382 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 383 | |
4fcdae83 SR |
384 | /* |
385 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 386 | */ |
a8227415 | 387 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 388 | |
7e53bd42 LJ |
389 | /* |
390 | * serialize the access of the ring buffer | |
391 | * | |
392 | * ring buffer serializes readers, but it is low level protection. | |
393 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
394 | * are not protected by ring buffer. | |
395 | * | |
396 | * The content of events may become garbage if we allow other process consumes | |
397 | * these events concurrently: | |
398 | * A) the page of the consumed events may become a normal page | |
399 | * (not reader page) in ring buffer, and this page will be rewrited | |
400 | * by events producer. | |
401 | * B) The page of the consumed events may become a page for splice_read, | |
402 | * and this page will be returned to system. | |
403 | * | |
404 | * These primitives allow multi process access to different cpu ring buffer | |
405 | * concurrently. | |
406 | * | |
407 | * These primitives don't distinguish read-only and read-consume access. | |
408 | * Multi read-only access are also serialized. | |
409 | */ | |
410 | ||
411 | #ifdef CONFIG_SMP | |
412 | static DECLARE_RWSEM(all_cpu_access_lock); | |
413 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
414 | ||
415 | static inline void trace_access_lock(int cpu) | |
416 | { | |
ae3b5093 | 417 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
418 | /* gain it for accessing the whole ring buffer. */ |
419 | down_write(&all_cpu_access_lock); | |
420 | } else { | |
421 | /* gain it for accessing a cpu ring buffer. */ | |
422 | ||
ae3b5093 | 423 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
424 | down_read(&all_cpu_access_lock); |
425 | ||
426 | /* Secondly block other access to this @cpu ring buffer. */ | |
427 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
428 | } | |
429 | } | |
430 | ||
431 | static inline void trace_access_unlock(int cpu) | |
432 | { | |
ae3b5093 | 433 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
434 | up_write(&all_cpu_access_lock); |
435 | } else { | |
436 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
437 | up_read(&all_cpu_access_lock); | |
438 | } | |
439 | } | |
440 | ||
441 | static inline void trace_access_lock_init(void) | |
442 | { | |
443 | int cpu; | |
444 | ||
445 | for_each_possible_cpu(cpu) | |
446 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
447 | } | |
448 | ||
449 | #else | |
450 | ||
451 | static DEFINE_MUTEX(access_lock); | |
452 | ||
453 | static inline void trace_access_lock(int cpu) | |
454 | { | |
455 | (void)cpu; | |
456 | mutex_lock(&access_lock); | |
457 | } | |
458 | ||
459 | static inline void trace_access_unlock(int cpu) | |
460 | { | |
461 | (void)cpu; | |
462 | mutex_unlock(&access_lock); | |
463 | } | |
464 | ||
465 | static inline void trace_access_lock_init(void) | |
466 | { | |
467 | } | |
468 | ||
469 | #endif | |
470 | ||
ee6bce52 | 471 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 472 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 473 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 | 474 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
328df475 | 475 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION; |
e7e2ee89 | 476 | |
5280bcef | 477 | static void tracer_tracing_on(struct trace_array *tr) |
10246fa3 SRRH |
478 | { |
479 | if (tr->trace_buffer.buffer) | |
480 | ring_buffer_record_on(tr->trace_buffer.buffer); | |
481 | /* | |
482 | * This flag is looked at when buffers haven't been allocated | |
483 | * yet, or by some tracers (like irqsoff), that just want to | |
484 | * know if the ring buffer has been disabled, but it can handle | |
485 | * races of where it gets disabled but we still do a record. | |
486 | * As the check is in the fast path of the tracers, it is more | |
487 | * important to be fast than accurate. | |
488 | */ | |
489 | tr->buffer_disabled = 0; | |
490 | /* Make the flag seen by readers */ | |
491 | smp_wmb(); | |
492 | } | |
493 | ||
499e5470 SR |
494 | /** |
495 | * tracing_on - enable tracing buffers | |
496 | * | |
497 | * This function enables tracing buffers that may have been | |
498 | * disabled with tracing_off. | |
499 | */ | |
500 | void tracing_on(void) | |
501 | { | |
10246fa3 | 502 | tracer_tracing_on(&global_trace); |
499e5470 SR |
503 | } |
504 | EXPORT_SYMBOL_GPL(tracing_on); | |
505 | ||
09ae7234 SRRH |
506 | /** |
507 | * __trace_puts - write a constant string into the trace buffer. | |
508 | * @ip: The address of the caller | |
509 | * @str: The constant string to write | |
510 | * @size: The size of the string. | |
511 | */ | |
512 | int __trace_puts(unsigned long ip, const char *str, int size) | |
513 | { | |
514 | struct ring_buffer_event *event; | |
515 | struct ring_buffer *buffer; | |
516 | struct print_entry *entry; | |
517 | unsigned long irq_flags; | |
518 | int alloc; | |
8abfb872 J |
519 | int pc; |
520 | ||
f0160a5a J |
521 | if (!(trace_flags & TRACE_ITER_PRINTK)) |
522 | return 0; | |
523 | ||
8abfb872 | 524 | pc = preempt_count(); |
09ae7234 | 525 | |
3132e107 SRRH |
526 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
527 | return 0; | |
528 | ||
09ae7234 SRRH |
529 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ |
530 | ||
531 | local_save_flags(irq_flags); | |
532 | buffer = global_trace.trace_buffer.buffer; | |
533 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, | |
8abfb872 | 534 | irq_flags, pc); |
09ae7234 SRRH |
535 | if (!event) |
536 | return 0; | |
537 | ||
538 | entry = ring_buffer_event_data(event); | |
539 | entry->ip = ip; | |
540 | ||
541 | memcpy(&entry->buf, str, size); | |
542 | ||
543 | /* Add a newline if necessary */ | |
544 | if (entry->buf[size - 1] != '\n') { | |
545 | entry->buf[size] = '\n'; | |
546 | entry->buf[size + 1] = '\0'; | |
547 | } else | |
548 | entry->buf[size] = '\0'; | |
549 | ||
550 | __buffer_unlock_commit(buffer, event); | |
8abfb872 | 551 | ftrace_trace_stack(buffer, irq_flags, 4, pc); |
09ae7234 SRRH |
552 | |
553 | return size; | |
554 | } | |
555 | EXPORT_SYMBOL_GPL(__trace_puts); | |
556 | ||
557 | /** | |
558 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
559 | * @ip: The address of the caller | |
560 | * @str: The constant string to write to the buffer to | |
561 | */ | |
562 | int __trace_bputs(unsigned long ip, const char *str) | |
563 | { | |
564 | struct ring_buffer_event *event; | |
565 | struct ring_buffer *buffer; | |
566 | struct bputs_entry *entry; | |
567 | unsigned long irq_flags; | |
568 | int size = sizeof(struct bputs_entry); | |
8abfb872 J |
569 | int pc; |
570 | ||
f0160a5a J |
571 | if (!(trace_flags & TRACE_ITER_PRINTK)) |
572 | return 0; | |
573 | ||
8abfb872 | 574 | pc = preempt_count(); |
09ae7234 | 575 | |
3132e107 SRRH |
576 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
577 | return 0; | |
578 | ||
09ae7234 SRRH |
579 | local_save_flags(irq_flags); |
580 | buffer = global_trace.trace_buffer.buffer; | |
581 | event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, | |
8abfb872 | 582 | irq_flags, pc); |
09ae7234 SRRH |
583 | if (!event) |
584 | return 0; | |
585 | ||
586 | entry = ring_buffer_event_data(event); | |
587 | entry->ip = ip; | |
588 | entry->str = str; | |
589 | ||
590 | __buffer_unlock_commit(buffer, event); | |
8abfb872 | 591 | ftrace_trace_stack(buffer, irq_flags, 4, pc); |
09ae7234 SRRH |
592 | |
593 | return 1; | |
594 | } | |
595 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
596 | ||
ad909e21 SRRH |
597 | #ifdef CONFIG_TRACER_SNAPSHOT |
598 | /** | |
599 | * trace_snapshot - take a snapshot of the current buffer. | |
600 | * | |
601 | * This causes a swap between the snapshot buffer and the current live | |
602 | * tracing buffer. You can use this to take snapshots of the live | |
603 | * trace when some condition is triggered, but continue to trace. | |
604 | * | |
605 | * Note, make sure to allocate the snapshot with either | |
606 | * a tracing_snapshot_alloc(), or by doing it manually | |
607 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
608 | * | |
609 | * If the snapshot buffer is not allocated, it will stop tracing. | |
610 | * Basically making a permanent snapshot. | |
611 | */ | |
612 | void tracing_snapshot(void) | |
613 | { | |
614 | struct trace_array *tr = &global_trace; | |
615 | struct tracer *tracer = tr->current_trace; | |
616 | unsigned long flags; | |
617 | ||
1b22e382 SRRH |
618 | if (in_nmi()) { |
619 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
620 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
621 | return; | |
622 | } | |
623 | ||
ad909e21 | 624 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
625 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
626 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
627 | tracing_off(); |
628 | return; | |
629 | } | |
630 | ||
631 | /* Note, snapshot can not be used when the tracer uses it */ | |
632 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
633 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
634 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
635 | return; |
636 | } | |
637 | ||
638 | local_irq_save(flags); | |
639 | update_max_tr(tr, current, smp_processor_id()); | |
640 | local_irq_restore(flags); | |
641 | } | |
1b22e382 | 642 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
643 | |
644 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
645 | struct trace_buffer *size_buf, int cpu_id); | |
3209cff4 SRRH |
646 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); |
647 | ||
648 | static int alloc_snapshot(struct trace_array *tr) | |
649 | { | |
650 | int ret; | |
651 | ||
652 | if (!tr->allocated_snapshot) { | |
653 | ||
654 | /* allocate spare buffer */ | |
655 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
656 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
657 | if (ret < 0) | |
658 | return ret; | |
659 | ||
660 | tr->allocated_snapshot = true; | |
661 | } | |
662 | ||
663 | return 0; | |
664 | } | |
665 | ||
ad1438a0 | 666 | static void free_snapshot(struct trace_array *tr) |
3209cff4 SRRH |
667 | { |
668 | /* | |
669 | * We don't free the ring buffer. instead, resize it because | |
670 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
671 | * we want preserve it. | |
672 | */ | |
673 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
674 | set_buffer_entries(&tr->max_buffer, 1); | |
675 | tracing_reset_online_cpus(&tr->max_buffer); | |
676 | tr->allocated_snapshot = false; | |
677 | } | |
ad909e21 | 678 | |
93e31ffb TZ |
679 | /** |
680 | * tracing_alloc_snapshot - allocate snapshot buffer. | |
681 | * | |
682 | * This only allocates the snapshot buffer if it isn't already | |
683 | * allocated - it doesn't also take a snapshot. | |
684 | * | |
685 | * This is meant to be used in cases where the snapshot buffer needs | |
686 | * to be set up for events that can't sleep but need to be able to | |
687 | * trigger a snapshot. | |
688 | */ | |
689 | int tracing_alloc_snapshot(void) | |
690 | { | |
691 | struct trace_array *tr = &global_trace; | |
692 | int ret; | |
693 | ||
694 | ret = alloc_snapshot(tr); | |
695 | WARN_ON(ret < 0); | |
696 | ||
697 | return ret; | |
698 | } | |
699 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
700 | ||
ad909e21 SRRH |
701 | /** |
702 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
703 | * | |
704 | * This is similar to trace_snapshot(), but it will allocate the | |
705 | * snapshot buffer if it isn't already allocated. Use this only | |
706 | * where it is safe to sleep, as the allocation may sleep. | |
707 | * | |
708 | * This causes a swap between the snapshot buffer and the current live | |
709 | * tracing buffer. You can use this to take snapshots of the live | |
710 | * trace when some condition is triggered, but continue to trace. | |
711 | */ | |
712 | void tracing_snapshot_alloc(void) | |
713 | { | |
ad909e21 SRRH |
714 | int ret; |
715 | ||
93e31ffb TZ |
716 | ret = tracing_alloc_snapshot(); |
717 | if (ret < 0) | |
3209cff4 | 718 | return; |
ad909e21 SRRH |
719 | |
720 | tracing_snapshot(); | |
721 | } | |
1b22e382 | 722 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
723 | #else |
724 | void tracing_snapshot(void) | |
725 | { | |
726 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
727 | } | |
1b22e382 | 728 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
93e31ffb TZ |
729 | int tracing_alloc_snapshot(void) |
730 | { | |
731 | WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); | |
732 | return -ENODEV; | |
733 | } | |
734 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
ad909e21 SRRH |
735 | void tracing_snapshot_alloc(void) |
736 | { | |
737 | /* Give warning */ | |
738 | tracing_snapshot(); | |
739 | } | |
1b22e382 | 740 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
741 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
742 | ||
5280bcef | 743 | static void tracer_tracing_off(struct trace_array *tr) |
10246fa3 SRRH |
744 | { |
745 | if (tr->trace_buffer.buffer) | |
746 | ring_buffer_record_off(tr->trace_buffer.buffer); | |
747 | /* | |
748 | * This flag is looked at when buffers haven't been allocated | |
749 | * yet, or by some tracers (like irqsoff), that just want to | |
750 | * know if the ring buffer has been disabled, but it can handle | |
751 | * races of where it gets disabled but we still do a record. | |
752 | * As the check is in the fast path of the tracers, it is more | |
753 | * important to be fast than accurate. | |
754 | */ | |
755 | tr->buffer_disabled = 1; | |
756 | /* Make the flag seen by readers */ | |
757 | smp_wmb(); | |
758 | } | |
759 | ||
499e5470 SR |
760 | /** |
761 | * tracing_off - turn off tracing buffers | |
762 | * | |
763 | * This function stops the tracing buffers from recording data. | |
764 | * It does not disable any overhead the tracers themselves may | |
765 | * be causing. This function simply causes all recording to | |
766 | * the ring buffers to fail. | |
767 | */ | |
768 | void tracing_off(void) | |
769 | { | |
10246fa3 | 770 | tracer_tracing_off(&global_trace); |
499e5470 SR |
771 | } |
772 | EXPORT_SYMBOL_GPL(tracing_off); | |
773 | ||
de7edd31 SRRH |
774 | void disable_trace_on_warning(void) |
775 | { | |
776 | if (__disable_trace_on_warning) | |
777 | tracing_off(); | |
778 | } | |
779 | ||
10246fa3 SRRH |
780 | /** |
781 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
782 | * @tr : the trace array to know if ring buffer is enabled | |
783 | * | |
784 | * Shows real state of the ring buffer if it is enabled or not. | |
785 | */ | |
5280bcef | 786 | static int tracer_tracing_is_on(struct trace_array *tr) |
10246fa3 SRRH |
787 | { |
788 | if (tr->trace_buffer.buffer) | |
789 | return ring_buffer_record_is_on(tr->trace_buffer.buffer); | |
790 | return !tr->buffer_disabled; | |
791 | } | |
792 | ||
499e5470 SR |
793 | /** |
794 | * tracing_is_on - show state of ring buffers enabled | |
795 | */ | |
796 | int tracing_is_on(void) | |
797 | { | |
10246fa3 | 798 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
799 | } |
800 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
801 | ||
3928a8a2 | 802 | static int __init set_buf_size(char *str) |
bc0c38d1 | 803 | { |
3928a8a2 | 804 | unsigned long buf_size; |
c6caeeb1 | 805 | |
bc0c38d1 SR |
806 | if (!str) |
807 | return 0; | |
9d612bef | 808 | buf_size = memparse(str, &str); |
c6caeeb1 | 809 | /* nr_entries can not be zero */ |
9d612bef | 810 | if (buf_size == 0) |
c6caeeb1 | 811 | return 0; |
3928a8a2 | 812 | trace_buf_size = buf_size; |
bc0c38d1 SR |
813 | return 1; |
814 | } | |
3928a8a2 | 815 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 816 | |
0e950173 TB |
817 | static int __init set_tracing_thresh(char *str) |
818 | { | |
87abb3b1 | 819 | unsigned long threshold; |
0e950173 TB |
820 | int ret; |
821 | ||
822 | if (!str) | |
823 | return 0; | |
bcd83ea6 | 824 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
825 | if (ret < 0) |
826 | return 0; | |
87abb3b1 | 827 | tracing_thresh = threshold * 1000; |
0e950173 TB |
828 | return 1; |
829 | } | |
830 | __setup("tracing_thresh=", set_tracing_thresh); | |
831 | ||
57f50be1 SR |
832 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
833 | { | |
834 | return nsecs / 1000; | |
835 | } | |
836 | ||
4fcdae83 | 837 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
838 | static const char *trace_options[] = { |
839 | "print-parent", | |
840 | "sym-offset", | |
841 | "sym-addr", | |
842 | "verbose", | |
f9896bf3 | 843 | "raw", |
5e3ca0ec | 844 | "hex", |
cb0f12aa | 845 | "bin", |
2a2cc8f7 | 846 | "block", |
86387f7e | 847 | "stacktrace", |
5e1607a0 | 848 | "trace_printk", |
b2a866f9 | 849 | "ftrace_preempt", |
9f029e83 | 850 | "branch", |
12ef7d44 | 851 | "annotate", |
02b67518 | 852 | "userstacktrace", |
b54d3de9 | 853 | "sym-userobj", |
66896a85 | 854 | "printk-msg-only", |
c4a8e8be | 855 | "context-info", |
c032ef64 | 856 | "latency-format", |
be6f164a | 857 | "sleep-time", |
a2a16d6a | 858 | "graph-time", |
e870e9a1 | 859 | "record-cmd", |
750912fa | 860 | "overwrite", |
cf30cf67 | 861 | "disable_on_free", |
77271ce4 | 862 | "irq-info", |
5224c3a3 | 863 | "markers", |
328df475 | 864 | "function-trace", |
bc0c38d1 SR |
865 | NULL |
866 | }; | |
867 | ||
5079f326 Z |
868 | static struct { |
869 | u64 (*func)(void); | |
870 | const char *name; | |
8be0709f | 871 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 872 | } trace_clocks[] = { |
1b3e5c09 TG |
873 | { trace_clock_local, "local", 1 }, |
874 | { trace_clock_global, "global", 1 }, | |
875 | { trace_clock_counter, "counter", 0 }, | |
e7fda6c4 | 876 | { trace_clock_jiffies, "uptime", 0 }, |
1b3e5c09 TG |
877 | { trace_clock, "perf", 1 }, |
878 | { ktime_get_mono_fast_ns, "mono", 1 }, | |
8cbd9cc6 | 879 | ARCH_TRACE_CLOCKS |
5079f326 Z |
880 | }; |
881 | ||
b63f39ea | 882 | /* |
883 | * trace_parser_get_init - gets the buffer for trace parser | |
884 | */ | |
885 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
886 | { | |
887 | memset(parser, 0, sizeof(*parser)); | |
888 | ||
889 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
890 | if (!parser->buffer) | |
891 | return 1; | |
892 | ||
893 | parser->size = size; | |
894 | return 0; | |
895 | } | |
896 | ||
897 | /* | |
898 | * trace_parser_put - frees the buffer for trace parser | |
899 | */ | |
900 | void trace_parser_put(struct trace_parser *parser) | |
901 | { | |
902 | kfree(parser->buffer); | |
903 | } | |
904 | ||
905 | /* | |
906 | * trace_get_user - reads the user input string separated by space | |
907 | * (matched by isspace(ch)) | |
908 | * | |
909 | * For each string found the 'struct trace_parser' is updated, | |
910 | * and the function returns. | |
911 | * | |
912 | * Returns number of bytes read. | |
913 | * | |
914 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
915 | */ | |
916 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
917 | size_t cnt, loff_t *ppos) | |
918 | { | |
919 | char ch; | |
920 | size_t read = 0; | |
921 | ssize_t ret; | |
922 | ||
923 | if (!*ppos) | |
924 | trace_parser_clear(parser); | |
925 | ||
926 | ret = get_user(ch, ubuf++); | |
927 | if (ret) | |
928 | goto out; | |
929 | ||
930 | read++; | |
931 | cnt--; | |
932 | ||
933 | /* | |
934 | * The parser is not finished with the last write, | |
935 | * continue reading the user input without skipping spaces. | |
936 | */ | |
937 | if (!parser->cont) { | |
938 | /* skip white space */ | |
939 | while (cnt && isspace(ch)) { | |
940 | ret = get_user(ch, ubuf++); | |
941 | if (ret) | |
942 | goto out; | |
943 | read++; | |
944 | cnt--; | |
945 | } | |
946 | ||
947 | /* only spaces were written */ | |
948 | if (isspace(ch)) { | |
949 | *ppos += read; | |
950 | ret = read; | |
951 | goto out; | |
952 | } | |
953 | ||
954 | parser->idx = 0; | |
955 | } | |
956 | ||
957 | /* read the non-space input */ | |
958 | while (cnt && !isspace(ch)) { | |
3c235a33 | 959 | if (parser->idx < parser->size - 1) |
b63f39ea | 960 | parser->buffer[parser->idx++] = ch; |
961 | else { | |
962 | ret = -EINVAL; | |
963 | goto out; | |
964 | } | |
965 | ret = get_user(ch, ubuf++); | |
966 | if (ret) | |
967 | goto out; | |
968 | read++; | |
969 | cnt--; | |
970 | } | |
971 | ||
972 | /* We either got finished input or we have to wait for another call. */ | |
973 | if (isspace(ch)) { | |
974 | parser->buffer[parser->idx] = 0; | |
975 | parser->cont = false; | |
057db848 | 976 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 977 | parser->cont = true; |
978 | parser->buffer[parser->idx++] = ch; | |
057db848 SR |
979 | } else { |
980 | ret = -EINVAL; | |
981 | goto out; | |
b63f39ea | 982 | } |
983 | ||
984 | *ppos += read; | |
985 | ret = read; | |
986 | ||
987 | out: | |
988 | return ret; | |
989 | } | |
990 | ||
3a161d99 | 991 | /* TODO add a seq_buf_to_buffer() */ |
b8b94265 | 992 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
993 | { |
994 | int len; | |
3c56819b | 995 | |
5ac48378 | 996 | if (trace_seq_used(s) <= s->seq.readpos) |
3c56819b EGM |
997 | return -EBUSY; |
998 | ||
5ac48378 | 999 | len = trace_seq_used(s) - s->seq.readpos; |
3c56819b EGM |
1000 | if (cnt > len) |
1001 | cnt = len; | |
3a161d99 | 1002 | memcpy(buf, s->buffer + s->seq.readpos, cnt); |
3c56819b | 1003 | |
3a161d99 | 1004 | s->seq.readpos += cnt; |
3c56819b EGM |
1005 | return cnt; |
1006 | } | |
1007 | ||
0e950173 TB |
1008 | unsigned long __read_mostly tracing_thresh; |
1009 | ||
5d4a9dba | 1010 | #ifdef CONFIG_TRACER_MAX_TRACE |
5d4a9dba SR |
1011 | /* |
1012 | * Copy the new maximum trace into the separate maximum-trace | |
1013 | * structure. (this way the maximum trace is permanently saved, | |
1014 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
1015 | */ | |
1016 | static void | |
1017 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
1018 | { | |
12883efb SRRH |
1019 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
1020 | struct trace_buffer *max_buf = &tr->max_buffer; | |
1021 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
1022 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 1023 | |
12883efb SRRH |
1024 | max_buf->cpu = cpu; |
1025 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 1026 | |
6d9b3fa5 | 1027 | max_data->saved_latency = tr->max_latency; |
8248ac05 SR |
1028 | max_data->critical_start = data->critical_start; |
1029 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 1030 | |
1acaa1b2 | 1031 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 1032 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
1033 | /* |
1034 | * If tsk == current, then use current_uid(), as that does not use | |
1035 | * RCU. The irq tracer can be called out of RCU scope. | |
1036 | */ | |
1037 | if (tsk == current) | |
1038 | max_data->uid = current_uid(); | |
1039 | else | |
1040 | max_data->uid = task_uid(tsk); | |
1041 | ||
8248ac05 SR |
1042 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
1043 | max_data->policy = tsk->policy; | |
1044 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
1045 | |
1046 | /* record this tasks comm */ | |
1047 | tracing_record_cmdline(tsk); | |
1048 | } | |
1049 | ||
4fcdae83 SR |
1050 | /** |
1051 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
1052 | * @tr: tracer | |
1053 | * @tsk: the task with the latency | |
1054 | * @cpu: The cpu that initiated the trace. | |
1055 | * | |
1056 | * Flip the buffers between the @tr and the max_tr and record information | |
1057 | * about which task was the cause of this latency. | |
1058 | */ | |
e309b41d | 1059 | void |
bc0c38d1 SR |
1060 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1061 | { | |
2721e72d | 1062 | struct ring_buffer *buf; |
bc0c38d1 | 1063 | |
2b6080f2 | 1064 | if (tr->stop_count) |
b8de7bd1 SR |
1065 | return; |
1066 | ||
4c11d7ae | 1067 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 1068 | |
45ad21ca | 1069 | if (!tr->allocated_snapshot) { |
debdd57f | 1070 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 1071 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 1072 | return; |
debdd57f | 1073 | } |
34600f0e | 1074 | |
0b9b12c1 | 1075 | arch_spin_lock(&tr->max_lock); |
3928a8a2 | 1076 | |
12883efb SRRH |
1077 | buf = tr->trace_buffer.buffer; |
1078 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
1079 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 1080 | |
bc0c38d1 | 1081 | __update_max_tr(tr, tsk, cpu); |
0b9b12c1 | 1082 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 SR |
1083 | } |
1084 | ||
1085 | /** | |
1086 | * update_max_tr_single - only copy one trace over, and reset the rest | |
1087 | * @tr - tracer | |
1088 | * @tsk - task with the latency | |
1089 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
1090 | * |
1091 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1092 | */ |
e309b41d | 1093 | void |
bc0c38d1 SR |
1094 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1095 | { | |
3928a8a2 | 1096 | int ret; |
bc0c38d1 | 1097 | |
2b6080f2 | 1098 | if (tr->stop_count) |
b8de7bd1 SR |
1099 | return; |
1100 | ||
4c11d7ae | 1101 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1102 | if (!tr->allocated_snapshot) { |
2930e04d | 1103 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1104 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1105 | return; |
2930e04d | 1106 | } |
ef710e10 | 1107 | |
0b9b12c1 | 1108 | arch_spin_lock(&tr->max_lock); |
bc0c38d1 | 1109 | |
12883efb | 1110 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 1111 | |
e8165dbb SR |
1112 | if (ret == -EBUSY) { |
1113 | /* | |
1114 | * We failed to swap the buffer due to a commit taking | |
1115 | * place on this CPU. We fail to record, but we reset | |
1116 | * the max trace buffer (no one writes directly to it) | |
1117 | * and flag that it failed. | |
1118 | */ | |
12883efb | 1119 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1120 | "Failed to swap buffers due to commit in progress\n"); |
1121 | } | |
1122 | ||
e8165dbb | 1123 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1124 | |
1125 | __update_max_tr(tr, tsk, cpu); | |
0b9b12c1 | 1126 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 | 1127 | } |
5d4a9dba | 1128 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1129 | |
e30f53aa | 1130 | static int wait_on_pipe(struct trace_iterator *iter, bool full) |
0d5c6e1c | 1131 | { |
15693458 SRRH |
1132 | /* Iterators are static, they should be filled or empty */ |
1133 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
8b8b3683 | 1134 | return 0; |
0d5c6e1c | 1135 | |
e30f53aa RV |
1136 | return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file, |
1137 | full); | |
0d5c6e1c SR |
1138 | } |
1139 | ||
f4e781c0 SRRH |
1140 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
1141 | static int run_tracer_selftest(struct tracer *type) | |
1142 | { | |
1143 | struct trace_array *tr = &global_trace; | |
1144 | struct tracer *saved_tracer = tr->current_trace; | |
1145 | int ret; | |
0d5c6e1c | 1146 | |
f4e781c0 SRRH |
1147 | if (!type->selftest || tracing_selftest_disabled) |
1148 | return 0; | |
0d5c6e1c SR |
1149 | |
1150 | /* | |
f4e781c0 SRRH |
1151 | * Run a selftest on this tracer. |
1152 | * Here we reset the trace buffer, and set the current | |
1153 | * tracer to be this tracer. The tracer can then run some | |
1154 | * internal tracing to verify that everything is in order. | |
1155 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1156 | */ |
f4e781c0 | 1157 | tracing_reset_online_cpus(&tr->trace_buffer); |
0d5c6e1c | 1158 | |
f4e781c0 SRRH |
1159 | tr->current_trace = type; |
1160 | ||
1161 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1162 | if (type->use_max_tr) { | |
1163 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1164 | if (ring_buffer_expanded) | |
1165 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1166 | RING_BUFFER_ALL_CPUS); | |
1167 | tr->allocated_snapshot = true; | |
1168 | } | |
1169 | #endif | |
1170 | ||
1171 | /* the test is responsible for initializing and enabling */ | |
1172 | pr_info("Testing tracer %s: ", type->name); | |
1173 | ret = type->selftest(type, tr); | |
1174 | /* the test is responsible for resetting too */ | |
1175 | tr->current_trace = saved_tracer; | |
1176 | if (ret) { | |
1177 | printk(KERN_CONT "FAILED!\n"); | |
1178 | /* Add the warning after printing 'FAILED' */ | |
1179 | WARN_ON(1); | |
1180 | return -1; | |
1181 | } | |
1182 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1183 | tracing_reset_online_cpus(&tr->trace_buffer); | |
1184 | ||
1185 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1186 | if (type->use_max_tr) { | |
1187 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1188 | |
f4e781c0 SRRH |
1189 | /* Shrink the max buffer again */ |
1190 | if (ring_buffer_expanded) | |
1191 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1192 | RING_BUFFER_ALL_CPUS); | |
1193 | } | |
1194 | #endif | |
1195 | ||
1196 | printk(KERN_CONT "PASSED\n"); | |
1197 | return 0; | |
1198 | } | |
1199 | #else | |
1200 | static inline int run_tracer_selftest(struct tracer *type) | |
1201 | { | |
1202 | return 0; | |
0d5c6e1c | 1203 | } |
f4e781c0 | 1204 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 1205 | |
4fcdae83 SR |
1206 | /** |
1207 | * register_tracer - register a tracer with the ftrace system. | |
1208 | * @type - the plugin for the tracer | |
1209 | * | |
1210 | * Register a new plugin tracer. | |
1211 | */ | |
bc0c38d1 SR |
1212 | int register_tracer(struct tracer *type) |
1213 | { | |
1214 | struct tracer *t; | |
bc0c38d1 SR |
1215 | int ret = 0; |
1216 | ||
1217 | if (!type->name) { | |
1218 | pr_info("Tracer must have a name\n"); | |
1219 | return -1; | |
1220 | } | |
1221 | ||
24a461d5 | 1222 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
1223 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
1224 | return -1; | |
1225 | } | |
1226 | ||
bc0c38d1 | 1227 | mutex_lock(&trace_types_lock); |
86fa2f60 | 1228 | |
8e1b82e0 FW |
1229 | tracing_selftest_running = true; |
1230 | ||
bc0c38d1 SR |
1231 | for (t = trace_types; t; t = t->next) { |
1232 | if (strcmp(type->name, t->name) == 0) { | |
1233 | /* already found */ | |
ee6c2c1b | 1234 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
1235 | type->name); |
1236 | ret = -1; | |
1237 | goto out; | |
1238 | } | |
1239 | } | |
1240 | ||
adf9f195 FW |
1241 | if (!type->set_flag) |
1242 | type->set_flag = &dummy_set_flag; | |
1243 | if (!type->flags) | |
1244 | type->flags = &dummy_tracer_flags; | |
1245 | else | |
1246 | if (!type->flags->opts) | |
1247 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 | 1248 | |
f4e781c0 SRRH |
1249 | ret = run_tracer_selftest(type); |
1250 | if (ret < 0) | |
1251 | goto out; | |
60a11774 | 1252 | |
bc0c38d1 SR |
1253 | type->next = trace_types; |
1254 | trace_types = type; | |
60a11774 | 1255 | |
bc0c38d1 | 1256 | out: |
8e1b82e0 | 1257 | tracing_selftest_running = false; |
bc0c38d1 SR |
1258 | mutex_unlock(&trace_types_lock); |
1259 | ||
dac74940 SR |
1260 | if (ret || !default_bootup_tracer) |
1261 | goto out_unlock; | |
1262 | ||
ee6c2c1b | 1263 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1264 | goto out_unlock; |
1265 | ||
1266 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1267 | /* Do we want this tracer to start on bootup? */ | |
607e2ea1 | 1268 | tracing_set_tracer(&global_trace, type->name); |
dac74940 SR |
1269 | default_bootup_tracer = NULL; |
1270 | /* disable other selftests, since this will break it. */ | |
55034cd6 | 1271 | tracing_selftest_disabled = true; |
b2821ae6 | 1272 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1273 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1274 | type->name); | |
b2821ae6 | 1275 | #endif |
b2821ae6 | 1276 | |
dac74940 | 1277 | out_unlock: |
bc0c38d1 SR |
1278 | return ret; |
1279 | } | |
1280 | ||
12883efb | 1281 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1282 | { |
12883efb | 1283 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1284 | |
a5416411 HT |
1285 | if (!buffer) |
1286 | return; | |
1287 | ||
f633903a SR |
1288 | ring_buffer_record_disable(buffer); |
1289 | ||
1290 | /* Make sure all commits have finished */ | |
1291 | synchronize_sched(); | |
68179686 | 1292 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1293 | |
1294 | ring_buffer_record_enable(buffer); | |
1295 | } | |
1296 | ||
12883efb | 1297 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1298 | { |
12883efb | 1299 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1300 | int cpu; |
1301 | ||
a5416411 HT |
1302 | if (!buffer) |
1303 | return; | |
1304 | ||
621968cd SR |
1305 | ring_buffer_record_disable(buffer); |
1306 | ||
1307 | /* Make sure all commits have finished */ | |
1308 | synchronize_sched(); | |
1309 | ||
9457158b | 1310 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 PE |
1311 | |
1312 | for_each_online_cpu(cpu) | |
68179686 | 1313 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1314 | |
1315 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1316 | } |
1317 | ||
09d8091c | 1318 | /* Must have trace_types_lock held */ |
873c642f | 1319 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1320 | { |
873c642f SRRH |
1321 | struct trace_array *tr; |
1322 | ||
873c642f | 1323 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
12883efb SRRH |
1324 | tracing_reset_online_cpus(&tr->trace_buffer); |
1325 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1326 | tracing_reset_online_cpus(&tr->max_buffer); | |
1327 | #endif | |
873c642f | 1328 | } |
9456f0fa SR |
1329 | } |
1330 | ||
939c7a4f | 1331 | #define SAVED_CMDLINES_DEFAULT 128 |
2c7eea4c | 1332 | #define NO_CMDLINE_MAP UINT_MAX |
edc35bd7 | 1333 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
939c7a4f YY |
1334 | struct saved_cmdlines_buffer { |
1335 | unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
1336 | unsigned *map_cmdline_to_pid; | |
1337 | unsigned cmdline_num; | |
1338 | int cmdline_idx; | |
1339 | char *saved_cmdlines; | |
1340 | }; | |
1341 | static struct saved_cmdlines_buffer *savedcmd; | |
25b0b44a | 1342 | |
25b0b44a | 1343 | /* temporary disable recording */ |
4fd27358 | 1344 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 | 1345 | |
939c7a4f YY |
1346 | static inline char *get_saved_cmdlines(int idx) |
1347 | { | |
1348 | return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN]; | |
1349 | } | |
1350 | ||
1351 | static inline void set_cmdline(int idx, const char *cmdline) | |
bc0c38d1 | 1352 | { |
939c7a4f YY |
1353 | memcpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); |
1354 | } | |
1355 | ||
1356 | static int allocate_cmdlines_buffer(unsigned int val, | |
1357 | struct saved_cmdlines_buffer *s) | |
1358 | { | |
1359 | s->map_cmdline_to_pid = kmalloc(val * sizeof(*s->map_cmdline_to_pid), | |
1360 | GFP_KERNEL); | |
1361 | if (!s->map_cmdline_to_pid) | |
1362 | return -ENOMEM; | |
1363 | ||
1364 | s->saved_cmdlines = kmalloc(val * TASK_COMM_LEN, GFP_KERNEL); | |
1365 | if (!s->saved_cmdlines) { | |
1366 | kfree(s->map_cmdline_to_pid); | |
1367 | return -ENOMEM; | |
1368 | } | |
1369 | ||
1370 | s->cmdline_idx = 0; | |
1371 | s->cmdline_num = val; | |
1372 | memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP, | |
1373 | sizeof(s->map_pid_to_cmdline)); | |
1374 | memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP, | |
1375 | val * sizeof(*s->map_cmdline_to_pid)); | |
1376 | ||
1377 | return 0; | |
1378 | } | |
1379 | ||
1380 | static int trace_create_savedcmd(void) | |
1381 | { | |
1382 | int ret; | |
1383 | ||
a6af8fbf | 1384 | savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL); |
939c7a4f YY |
1385 | if (!savedcmd) |
1386 | return -ENOMEM; | |
1387 | ||
1388 | ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd); | |
1389 | if (ret < 0) { | |
1390 | kfree(savedcmd); | |
1391 | savedcmd = NULL; | |
1392 | return -ENOMEM; | |
1393 | } | |
1394 | ||
1395 | return 0; | |
bc0c38d1 SR |
1396 | } |
1397 | ||
b5130b1e CE |
1398 | int is_tracing_stopped(void) |
1399 | { | |
2b6080f2 | 1400 | return global_trace.stop_count; |
b5130b1e CE |
1401 | } |
1402 | ||
0f048701 SR |
1403 | /** |
1404 | * tracing_start - quick start of the tracer | |
1405 | * | |
1406 | * If tracing is enabled but was stopped by tracing_stop, | |
1407 | * this will start the tracer back up. | |
1408 | */ | |
1409 | void tracing_start(void) | |
1410 | { | |
1411 | struct ring_buffer *buffer; | |
1412 | unsigned long flags; | |
1413 | ||
1414 | if (tracing_disabled) | |
1415 | return; | |
1416 | ||
2b6080f2 SR |
1417 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1418 | if (--global_trace.stop_count) { | |
1419 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1420 | /* Someone screwed up their debugging */ |
1421 | WARN_ON_ONCE(1); | |
2b6080f2 | 1422 | global_trace.stop_count = 0; |
b06a8301 | 1423 | } |
0f048701 SR |
1424 | goto out; |
1425 | } | |
1426 | ||
a2f80714 | 1427 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1428 | arch_spin_lock(&global_trace.max_lock); |
0f048701 | 1429 | |
12883efb | 1430 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1431 | if (buffer) |
1432 | ring_buffer_record_enable(buffer); | |
1433 | ||
12883efb SRRH |
1434 | #ifdef CONFIG_TRACER_MAX_TRACE |
1435 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1436 | if (buffer) |
1437 | ring_buffer_record_enable(buffer); | |
12883efb | 1438 | #endif |
0f048701 | 1439 | |
0b9b12c1 | 1440 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1441 | |
0f048701 | 1442 | out: |
2b6080f2 SR |
1443 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1444 | } | |
1445 | ||
1446 | static void tracing_start_tr(struct trace_array *tr) | |
1447 | { | |
1448 | struct ring_buffer *buffer; | |
1449 | unsigned long flags; | |
1450 | ||
1451 | if (tracing_disabled) | |
1452 | return; | |
1453 | ||
1454 | /* If global, we need to also start the max tracer */ | |
1455 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1456 | return tracing_start(); | |
1457 | ||
1458 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1459 | ||
1460 | if (--tr->stop_count) { | |
1461 | if (tr->stop_count < 0) { | |
1462 | /* Someone screwed up their debugging */ | |
1463 | WARN_ON_ONCE(1); | |
1464 | tr->stop_count = 0; | |
1465 | } | |
1466 | goto out; | |
1467 | } | |
1468 | ||
12883efb | 1469 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1470 | if (buffer) |
1471 | ring_buffer_record_enable(buffer); | |
1472 | ||
1473 | out: | |
1474 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1475 | } |
1476 | ||
1477 | /** | |
1478 | * tracing_stop - quick stop of the tracer | |
1479 | * | |
1480 | * Light weight way to stop tracing. Use in conjunction with | |
1481 | * tracing_start. | |
1482 | */ | |
1483 | void tracing_stop(void) | |
1484 | { | |
1485 | struct ring_buffer *buffer; | |
1486 | unsigned long flags; | |
1487 | ||
2b6080f2 SR |
1488 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1489 | if (global_trace.stop_count++) | |
0f048701 SR |
1490 | goto out; |
1491 | ||
a2f80714 | 1492 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1493 | arch_spin_lock(&global_trace.max_lock); |
a2f80714 | 1494 | |
12883efb | 1495 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1496 | if (buffer) |
1497 | ring_buffer_record_disable(buffer); | |
1498 | ||
12883efb SRRH |
1499 | #ifdef CONFIG_TRACER_MAX_TRACE |
1500 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1501 | if (buffer) |
1502 | ring_buffer_record_disable(buffer); | |
12883efb | 1503 | #endif |
0f048701 | 1504 | |
0b9b12c1 | 1505 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1506 | |
0f048701 | 1507 | out: |
2b6080f2 SR |
1508 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1509 | } | |
1510 | ||
1511 | static void tracing_stop_tr(struct trace_array *tr) | |
1512 | { | |
1513 | struct ring_buffer *buffer; | |
1514 | unsigned long flags; | |
1515 | ||
1516 | /* If global, we need to also stop the max tracer */ | |
1517 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1518 | return tracing_stop(); | |
1519 | ||
1520 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1521 | if (tr->stop_count++) | |
1522 | goto out; | |
1523 | ||
12883efb | 1524 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1525 | if (buffer) |
1526 | ring_buffer_record_disable(buffer); | |
1527 | ||
1528 | out: | |
1529 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1530 | } |
1531 | ||
e309b41d | 1532 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1533 | |
379cfdac | 1534 | static int trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1535 | { |
a635cf04 | 1536 | unsigned pid, idx; |
bc0c38d1 SR |
1537 | |
1538 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
379cfdac | 1539 | return 0; |
bc0c38d1 SR |
1540 | |
1541 | /* | |
1542 | * It's not the end of the world if we don't get | |
1543 | * the lock, but we also don't want to spin | |
1544 | * nor do we want to disable interrupts, | |
1545 | * so if we miss here, then better luck next time. | |
1546 | */ | |
0199c4e6 | 1547 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
379cfdac | 1548 | return 0; |
bc0c38d1 | 1549 | |
939c7a4f | 1550 | idx = savedcmd->map_pid_to_cmdline[tsk->pid]; |
2c7eea4c | 1551 | if (idx == NO_CMDLINE_MAP) { |
939c7a4f | 1552 | idx = (savedcmd->cmdline_idx + 1) % savedcmd->cmdline_num; |
bc0c38d1 | 1553 | |
a635cf04 CE |
1554 | /* |
1555 | * Check whether the cmdline buffer at idx has a pid | |
1556 | * mapped. We are going to overwrite that entry so we | |
1557 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1558 | * would read the new comm for the old pid. | |
1559 | */ | |
939c7a4f | 1560 | pid = savedcmd->map_cmdline_to_pid[idx]; |
a635cf04 | 1561 | if (pid != NO_CMDLINE_MAP) |
939c7a4f | 1562 | savedcmd->map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; |
bc0c38d1 | 1563 | |
939c7a4f YY |
1564 | savedcmd->map_cmdline_to_pid[idx] = tsk->pid; |
1565 | savedcmd->map_pid_to_cmdline[tsk->pid] = idx; | |
bc0c38d1 | 1566 | |
939c7a4f | 1567 | savedcmd->cmdline_idx = idx; |
bc0c38d1 SR |
1568 | } |
1569 | ||
939c7a4f | 1570 | set_cmdline(idx, tsk->comm); |
bc0c38d1 | 1571 | |
0199c4e6 | 1572 | arch_spin_unlock(&trace_cmdline_lock); |
379cfdac SRRH |
1573 | |
1574 | return 1; | |
bc0c38d1 SR |
1575 | } |
1576 | ||
4c27e756 | 1577 | static void __trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1578 | { |
bc0c38d1 SR |
1579 | unsigned map; |
1580 | ||
4ca53085 SR |
1581 | if (!pid) { |
1582 | strcpy(comm, "<idle>"); | |
1583 | return; | |
1584 | } | |
bc0c38d1 | 1585 | |
74bf4076 SR |
1586 | if (WARN_ON_ONCE(pid < 0)) { |
1587 | strcpy(comm, "<XXX>"); | |
1588 | return; | |
1589 | } | |
1590 | ||
4ca53085 SR |
1591 | if (pid > PID_MAX_DEFAULT) { |
1592 | strcpy(comm, "<...>"); | |
1593 | return; | |
1594 | } | |
bc0c38d1 | 1595 | |
939c7a4f | 1596 | map = savedcmd->map_pid_to_cmdline[pid]; |
50d88758 | 1597 | if (map != NO_CMDLINE_MAP) |
939c7a4f | 1598 | strcpy(comm, get_saved_cmdlines(map)); |
50d88758 TG |
1599 | else |
1600 | strcpy(comm, "<...>"); | |
4c27e756 SRRH |
1601 | } |
1602 | ||
1603 | void trace_find_cmdline(int pid, char comm[]) | |
1604 | { | |
1605 | preempt_disable(); | |
1606 | arch_spin_lock(&trace_cmdline_lock); | |
1607 | ||
1608 | __trace_find_cmdline(pid, comm); | |
bc0c38d1 | 1609 | |
0199c4e6 | 1610 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1611 | preempt_enable(); |
bc0c38d1 SR |
1612 | } |
1613 | ||
e309b41d | 1614 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1615 | { |
0fb9656d | 1616 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1617 | return; |
1618 | ||
7ffbd48d SR |
1619 | if (!__this_cpu_read(trace_cmdline_save)) |
1620 | return; | |
1621 | ||
379cfdac SRRH |
1622 | if (trace_save_cmdline(tsk)) |
1623 | __this_cpu_write(trace_cmdline_save, false); | |
bc0c38d1 SR |
1624 | } |
1625 | ||
45dcd8b8 | 1626 | void |
38697053 SR |
1627 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1628 | int pc) | |
bc0c38d1 SR |
1629 | { |
1630 | struct task_struct *tsk = current; | |
bc0c38d1 | 1631 | |
777e208d SR |
1632 | entry->preempt_count = pc & 0xff; |
1633 | entry->pid = (tsk) ? tsk->pid : 0; | |
1634 | entry->flags = | |
9244489a | 1635 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1636 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1637 | #else |
1638 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1639 | #endif | |
bc0c38d1 SR |
1640 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1641 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
e5137b50 PZ |
1642 | (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) | |
1643 | (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0); | |
bc0c38d1 | 1644 | } |
f413cdb8 | 1645 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1646 | |
e77405ad SR |
1647 | struct ring_buffer_event * |
1648 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1649 | int type, | |
1650 | unsigned long len, | |
1651 | unsigned long flags, int pc) | |
51a763dd ACM |
1652 | { |
1653 | struct ring_buffer_event *event; | |
1654 | ||
e77405ad | 1655 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1656 | if (event != NULL) { |
1657 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1658 | ||
1659 | tracing_generic_entry_update(ent, flags, pc); | |
1660 | ent->type = type; | |
1661 | } | |
1662 | ||
1663 | return event; | |
1664 | } | |
51a763dd | 1665 | |
7ffbd48d SR |
1666 | void |
1667 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
1668 | { | |
1669 | __this_cpu_write(trace_cmdline_save, true); | |
1670 | ring_buffer_unlock_commit(buffer, event); | |
1671 | } | |
1672 | ||
e77405ad SR |
1673 | static inline void |
1674 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1675 | struct ring_buffer_event *event, | |
0d5c6e1c | 1676 | unsigned long flags, int pc) |
51a763dd | 1677 | { |
7ffbd48d | 1678 | __buffer_unlock_commit(buffer, event); |
51a763dd | 1679 | |
e77405ad SR |
1680 | ftrace_trace_stack(buffer, flags, 6, pc); |
1681 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1682 | } |
1683 | ||
e77405ad SR |
1684 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1685 | struct ring_buffer_event *event, | |
1686 | unsigned long flags, int pc) | |
07edf712 | 1687 | { |
0d5c6e1c | 1688 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
51a763dd | 1689 | } |
0d5c6e1c | 1690 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); |
51a763dd | 1691 | |
2c4a33ab SRRH |
1692 | static struct ring_buffer *temp_buffer; |
1693 | ||
ccb469a1 SR |
1694 | struct ring_buffer_event * |
1695 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
1696 | struct ftrace_event_file *ftrace_file, | |
1697 | int type, unsigned long len, | |
1698 | unsigned long flags, int pc) | |
1699 | { | |
2c4a33ab SRRH |
1700 | struct ring_buffer_event *entry; |
1701 | ||
12883efb | 1702 | *current_rb = ftrace_file->tr->trace_buffer.buffer; |
2c4a33ab | 1703 | entry = trace_buffer_lock_reserve(*current_rb, |
ccb469a1 | 1704 | type, len, flags, pc); |
2c4a33ab SRRH |
1705 | /* |
1706 | * If tracing is off, but we have triggers enabled | |
1707 | * we still need to look at the event data. Use the temp_buffer | |
1708 | * to store the trace event for the tigger to use. It's recusive | |
1709 | * safe and will not be recorded anywhere. | |
1710 | */ | |
1711 | if (!entry && ftrace_file->flags & FTRACE_EVENT_FL_TRIGGER_COND) { | |
1712 | *current_rb = temp_buffer; | |
1713 | entry = trace_buffer_lock_reserve(*current_rb, | |
1714 | type, len, flags, pc); | |
1715 | } | |
1716 | return entry; | |
ccb469a1 SR |
1717 | } |
1718 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
1719 | ||
ef5580d0 | 1720 | struct ring_buffer_event * |
e77405ad SR |
1721 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1722 | int type, unsigned long len, | |
ef5580d0 SR |
1723 | unsigned long flags, int pc) |
1724 | { | |
12883efb | 1725 | *current_rb = global_trace.trace_buffer.buffer; |
e77405ad | 1726 | return trace_buffer_lock_reserve(*current_rb, |
ef5580d0 SR |
1727 | type, len, flags, pc); |
1728 | } | |
94487d6d | 1729 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1730 | |
e77405ad SR |
1731 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1732 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1733 | unsigned long flags, int pc) |
1734 | { | |
0d5c6e1c | 1735 | __trace_buffer_unlock_commit(buffer, event, flags, pc); |
07edf712 | 1736 | } |
94487d6d | 1737 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1738 | |
0d5c6e1c SR |
1739 | void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1740 | struct ring_buffer_event *event, | |
1741 | unsigned long flags, int pc, | |
1742 | struct pt_regs *regs) | |
1fd8df2c | 1743 | { |
7ffbd48d | 1744 | __buffer_unlock_commit(buffer, event); |
1fd8df2c MH |
1745 | |
1746 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1747 | ftrace_trace_userstack(buffer, flags, pc); | |
1748 | } | |
0d5c6e1c | 1749 | EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); |
1fd8df2c | 1750 | |
e77405ad SR |
1751 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1752 | struct ring_buffer_event *event) | |
77d9f465 | 1753 | { |
e77405ad | 1754 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1755 | } |
12acd473 | 1756 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1757 | |
e309b41d | 1758 | void |
7be42151 | 1759 | trace_function(struct trace_array *tr, |
38697053 SR |
1760 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1761 | int pc) | |
bc0c38d1 | 1762 | { |
e1112b4d | 1763 | struct ftrace_event_call *call = &event_function; |
12883efb | 1764 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 1765 | struct ring_buffer_event *event; |
777e208d | 1766 | struct ftrace_entry *entry; |
bc0c38d1 | 1767 | |
d769041f | 1768 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1769 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1770 | return; |
1771 | ||
e77405ad | 1772 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1773 | flags, pc); |
3928a8a2 SR |
1774 | if (!event) |
1775 | return; | |
1776 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1777 | entry->ip = ip; |
1778 | entry->parent_ip = parent_ip; | |
e1112b4d | 1779 | |
f306cc82 | 1780 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1781 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
1782 | } |
1783 | ||
c0a0d0d3 | 1784 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1785 | |
1786 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1787 | struct ftrace_stack { | |
1788 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1789 | }; | |
1790 | ||
1791 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1792 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1793 | ||
e77405ad | 1794 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1795 | unsigned long flags, |
1fd8df2c | 1796 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1797 | { |
e1112b4d | 1798 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1799 | struct ring_buffer_event *event; |
777e208d | 1800 | struct stack_entry *entry; |
86387f7e | 1801 | struct stack_trace trace; |
4a9bd3f1 SR |
1802 | int use_stack; |
1803 | int size = FTRACE_STACK_ENTRIES; | |
1804 | ||
1805 | trace.nr_entries = 0; | |
1806 | trace.skip = skip; | |
1807 | ||
1808 | /* | |
1809 | * Since events can happen in NMIs there's no safe way to | |
1810 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1811 | * or NMI comes in, it will just have to use the default | |
1812 | * FTRACE_STACK_SIZE. | |
1813 | */ | |
1814 | preempt_disable_notrace(); | |
1815 | ||
82146529 | 1816 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
1817 | /* |
1818 | * We don't need any atomic variables, just a barrier. | |
1819 | * If an interrupt comes in, we don't care, because it would | |
1820 | * have exited and put the counter back to what we want. | |
1821 | * We just need a barrier to keep gcc from moving things | |
1822 | * around. | |
1823 | */ | |
1824 | barrier(); | |
1825 | if (use_stack == 1) { | |
bdffd893 | 1826 | trace.entries = this_cpu_ptr(ftrace_stack.calls); |
4a9bd3f1 SR |
1827 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; |
1828 | ||
1829 | if (regs) | |
1830 | save_stack_trace_regs(regs, &trace); | |
1831 | else | |
1832 | save_stack_trace(&trace); | |
1833 | ||
1834 | if (trace.nr_entries > size) | |
1835 | size = trace.nr_entries; | |
1836 | } else | |
1837 | /* From now on, use_stack is a boolean */ | |
1838 | use_stack = 0; | |
1839 | ||
1840 | size *= sizeof(unsigned long); | |
86387f7e | 1841 | |
e77405ad | 1842 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1843 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1844 | if (!event) |
4a9bd3f1 SR |
1845 | goto out; |
1846 | entry = ring_buffer_event_data(event); | |
86387f7e | 1847 | |
4a9bd3f1 SR |
1848 | memset(&entry->caller, 0, size); |
1849 | ||
1850 | if (use_stack) | |
1851 | memcpy(&entry->caller, trace.entries, | |
1852 | trace.nr_entries * sizeof(unsigned long)); | |
1853 | else { | |
1854 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1855 | trace.entries = entry->caller; | |
1856 | if (regs) | |
1857 | save_stack_trace_regs(regs, &trace); | |
1858 | else | |
1859 | save_stack_trace(&trace); | |
1860 | } | |
1861 | ||
1862 | entry->size = trace.nr_entries; | |
86387f7e | 1863 | |
f306cc82 | 1864 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1865 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
1866 | |
1867 | out: | |
1868 | /* Again, don't let gcc optimize things here */ | |
1869 | barrier(); | |
82146529 | 1870 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
1871 | preempt_enable_notrace(); |
1872 | ||
f0a920d5 IM |
1873 | } |
1874 | ||
1fd8df2c MH |
1875 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1876 | int skip, int pc, struct pt_regs *regs) | |
1877 | { | |
1878 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1879 | return; | |
1880 | ||
1881 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1882 | } | |
1883 | ||
e77405ad SR |
1884 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1885 | int skip, int pc) | |
53614991 SR |
1886 | { |
1887 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1888 | return; | |
1889 | ||
1fd8df2c | 1890 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1891 | } |
1892 | ||
c0a0d0d3 FW |
1893 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1894 | int pc) | |
38697053 | 1895 | { |
12883efb | 1896 | __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); |
38697053 SR |
1897 | } |
1898 | ||
03889384 SR |
1899 | /** |
1900 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 1901 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 1902 | */ |
c142be8e | 1903 | void trace_dump_stack(int skip) |
03889384 SR |
1904 | { |
1905 | unsigned long flags; | |
1906 | ||
1907 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1908 | return; |
03889384 SR |
1909 | |
1910 | local_save_flags(flags); | |
1911 | ||
c142be8e SRRH |
1912 | /* |
1913 | * Skip 3 more, seems to get us at the caller of | |
1914 | * this function. | |
1915 | */ | |
1916 | skip += 3; | |
1917 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, | |
1918 | flags, skip, preempt_count(), NULL); | |
03889384 SR |
1919 | } |
1920 | ||
91e86e56 SR |
1921 | static DEFINE_PER_CPU(int, user_stack_count); |
1922 | ||
e77405ad SR |
1923 | void |
1924 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1925 | { |
e1112b4d | 1926 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1927 | struct ring_buffer_event *event; |
02b67518 TE |
1928 | struct userstack_entry *entry; |
1929 | struct stack_trace trace; | |
02b67518 TE |
1930 | |
1931 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1932 | return; | |
1933 | ||
b6345879 SR |
1934 | /* |
1935 | * NMIs can not handle page faults, even with fix ups. | |
1936 | * The save user stack can (and often does) fault. | |
1937 | */ | |
1938 | if (unlikely(in_nmi())) | |
1939 | return; | |
02b67518 | 1940 | |
91e86e56 SR |
1941 | /* |
1942 | * prevent recursion, since the user stack tracing may | |
1943 | * trigger other kernel events. | |
1944 | */ | |
1945 | preempt_disable(); | |
1946 | if (__this_cpu_read(user_stack_count)) | |
1947 | goto out; | |
1948 | ||
1949 | __this_cpu_inc(user_stack_count); | |
1950 | ||
e77405ad | 1951 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1952 | sizeof(*entry), flags, pc); |
02b67518 | 1953 | if (!event) |
1dbd1951 | 1954 | goto out_drop_count; |
02b67518 | 1955 | entry = ring_buffer_event_data(event); |
02b67518 | 1956 | |
48659d31 | 1957 | entry->tgid = current->tgid; |
02b67518 TE |
1958 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1959 | ||
1960 | trace.nr_entries = 0; | |
1961 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1962 | trace.skip = 0; | |
1963 | trace.entries = entry->caller; | |
1964 | ||
1965 | save_stack_trace_user(&trace); | |
f306cc82 | 1966 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 1967 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 1968 | |
1dbd1951 | 1969 | out_drop_count: |
91e86e56 | 1970 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1971 | out: |
1972 | preempt_enable(); | |
02b67518 TE |
1973 | } |
1974 | ||
4fd27358 HE |
1975 | #ifdef UNUSED |
1976 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1977 | { |
7be42151 | 1978 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1979 | } |
4fd27358 | 1980 | #endif /* UNUSED */ |
02b67518 | 1981 | |
c0a0d0d3 FW |
1982 | #endif /* CONFIG_STACKTRACE */ |
1983 | ||
07d777fe SR |
1984 | /* created for use with alloc_percpu */ |
1985 | struct trace_buffer_struct { | |
1986 | char buffer[TRACE_BUF_SIZE]; | |
1987 | }; | |
1988 | ||
1989 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1990 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1991 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1992 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1993 | ||
1994 | /* | |
1995 | * The buffer used is dependent on the context. There is a per cpu | |
1996 | * buffer for normal context, softirq contex, hard irq context and | |
1997 | * for NMI context. Thise allows for lockless recording. | |
1998 | * | |
1999 | * Note, if the buffers failed to be allocated, then this returns NULL | |
2000 | */ | |
2001 | static char *get_trace_buf(void) | |
2002 | { | |
2003 | struct trace_buffer_struct *percpu_buffer; | |
07d777fe SR |
2004 | |
2005 | /* | |
2006 | * If we have allocated per cpu buffers, then we do not | |
2007 | * need to do any locking. | |
2008 | */ | |
2009 | if (in_nmi()) | |
2010 | percpu_buffer = trace_percpu_nmi_buffer; | |
2011 | else if (in_irq()) | |
2012 | percpu_buffer = trace_percpu_irq_buffer; | |
2013 | else if (in_softirq()) | |
2014 | percpu_buffer = trace_percpu_sirq_buffer; | |
2015 | else | |
2016 | percpu_buffer = trace_percpu_buffer; | |
2017 | ||
2018 | if (!percpu_buffer) | |
2019 | return NULL; | |
2020 | ||
d8a0349c | 2021 | return this_cpu_ptr(&percpu_buffer->buffer[0]); |
07d777fe SR |
2022 | } |
2023 | ||
2024 | static int alloc_percpu_trace_buffer(void) | |
2025 | { | |
2026 | struct trace_buffer_struct *buffers; | |
2027 | struct trace_buffer_struct *sirq_buffers; | |
2028 | struct trace_buffer_struct *irq_buffers; | |
2029 | struct trace_buffer_struct *nmi_buffers; | |
2030 | ||
2031 | buffers = alloc_percpu(struct trace_buffer_struct); | |
2032 | if (!buffers) | |
2033 | goto err_warn; | |
2034 | ||
2035 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
2036 | if (!sirq_buffers) | |
2037 | goto err_sirq; | |
2038 | ||
2039 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
2040 | if (!irq_buffers) | |
2041 | goto err_irq; | |
2042 | ||
2043 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
2044 | if (!nmi_buffers) | |
2045 | goto err_nmi; | |
2046 | ||
2047 | trace_percpu_buffer = buffers; | |
2048 | trace_percpu_sirq_buffer = sirq_buffers; | |
2049 | trace_percpu_irq_buffer = irq_buffers; | |
2050 | trace_percpu_nmi_buffer = nmi_buffers; | |
2051 | ||
2052 | return 0; | |
2053 | ||
2054 | err_nmi: | |
2055 | free_percpu(irq_buffers); | |
2056 | err_irq: | |
2057 | free_percpu(sirq_buffers); | |
2058 | err_sirq: | |
2059 | free_percpu(buffers); | |
2060 | err_warn: | |
2061 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
2062 | return -ENOMEM; | |
2063 | } | |
2064 | ||
81698831 SR |
2065 | static int buffers_allocated; |
2066 | ||
07d777fe SR |
2067 | void trace_printk_init_buffers(void) |
2068 | { | |
07d777fe SR |
2069 | if (buffers_allocated) |
2070 | return; | |
2071 | ||
2072 | if (alloc_percpu_trace_buffer()) | |
2073 | return; | |
2074 | ||
2184db46 SR |
2075 | /* trace_printk() is for debug use only. Don't use it in production. */ |
2076 | ||
69a1c994 BP |
2077 | pr_warning("\n"); |
2078 | pr_warning("**********************************************************\n"); | |
2184db46 SR |
2079 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); |
2080 | pr_warning("** **\n"); | |
2081 | pr_warning("** trace_printk() being used. Allocating extra memory. **\n"); | |
2082 | pr_warning("** **\n"); | |
2083 | pr_warning("** This means that this is a DEBUG kernel and it is **\n"); | |
eff264ef | 2084 | pr_warning("** unsafe for production use. **\n"); |
2184db46 SR |
2085 | pr_warning("** **\n"); |
2086 | pr_warning("** If you see this message and you are not debugging **\n"); | |
2087 | pr_warning("** the kernel, report this immediately to your vendor! **\n"); | |
2088 | pr_warning("** **\n"); | |
2089 | pr_warning("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
2090 | pr_warning("**********************************************************\n"); | |
07d777fe | 2091 | |
b382ede6 SR |
2092 | /* Expand the buffers to set size */ |
2093 | tracing_update_buffers(); | |
2094 | ||
07d777fe | 2095 | buffers_allocated = 1; |
81698831 SR |
2096 | |
2097 | /* | |
2098 | * trace_printk_init_buffers() can be called by modules. | |
2099 | * If that happens, then we need to start cmdline recording | |
2100 | * directly here. If the global_trace.buffer is already | |
2101 | * allocated here, then this was called by module code. | |
2102 | */ | |
12883efb | 2103 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
2104 | tracing_start_cmdline_record(); |
2105 | } | |
2106 | ||
2107 | void trace_printk_start_comm(void) | |
2108 | { | |
2109 | /* Start tracing comms if trace printk is set */ | |
2110 | if (!buffers_allocated) | |
2111 | return; | |
2112 | tracing_start_cmdline_record(); | |
2113 | } | |
2114 | ||
2115 | static void trace_printk_start_stop_comm(int enabled) | |
2116 | { | |
2117 | if (!buffers_allocated) | |
2118 | return; | |
2119 | ||
2120 | if (enabled) | |
2121 | tracing_start_cmdline_record(); | |
2122 | else | |
2123 | tracing_stop_cmdline_record(); | |
07d777fe SR |
2124 | } |
2125 | ||
769b0441 | 2126 | /** |
48ead020 | 2127 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
2128 | * |
2129 | */ | |
40ce74f1 | 2130 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 2131 | { |
e1112b4d | 2132 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 2133 | struct ring_buffer_event *event; |
e77405ad | 2134 | struct ring_buffer *buffer; |
769b0441 | 2135 | struct trace_array *tr = &global_trace; |
48ead020 | 2136 | struct bprint_entry *entry; |
769b0441 | 2137 | unsigned long flags; |
07d777fe SR |
2138 | char *tbuffer; |
2139 | int len = 0, size, pc; | |
769b0441 FW |
2140 | |
2141 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
2142 | return 0; | |
2143 | ||
2144 | /* Don't pollute graph traces with trace_vprintk internals */ | |
2145 | pause_graph_tracing(); | |
2146 | ||
2147 | pc = preempt_count(); | |
5168ae50 | 2148 | preempt_disable_notrace(); |
769b0441 | 2149 | |
07d777fe SR |
2150 | tbuffer = get_trace_buf(); |
2151 | if (!tbuffer) { | |
2152 | len = 0; | |
769b0441 | 2153 | goto out; |
07d777fe | 2154 | } |
769b0441 | 2155 | |
07d777fe | 2156 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 2157 | |
07d777fe SR |
2158 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
2159 | goto out; | |
769b0441 | 2160 | |
07d777fe | 2161 | local_save_flags(flags); |
769b0441 | 2162 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 2163 | buffer = tr->trace_buffer.buffer; |
e77405ad SR |
2164 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
2165 | flags, pc); | |
769b0441 | 2166 | if (!event) |
07d777fe | 2167 | goto out; |
769b0441 FW |
2168 | entry = ring_buffer_event_data(event); |
2169 | entry->ip = ip; | |
769b0441 FW |
2170 | entry->fmt = fmt; |
2171 | ||
07d777fe | 2172 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
f306cc82 | 2173 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2174 | __buffer_unlock_commit(buffer, event); |
d931369b SR |
2175 | ftrace_trace_stack(buffer, flags, 6, pc); |
2176 | } | |
769b0441 | 2177 | |
769b0441 | 2178 | out: |
5168ae50 | 2179 | preempt_enable_notrace(); |
769b0441 FW |
2180 | unpause_graph_tracing(); |
2181 | ||
2182 | return len; | |
2183 | } | |
48ead020 FW |
2184 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
2185 | ||
12883efb SRRH |
2186 | static int |
2187 | __trace_array_vprintk(struct ring_buffer *buffer, | |
2188 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 2189 | { |
e1112b4d | 2190 | struct ftrace_event_call *call = &event_print; |
48ead020 | 2191 | struct ring_buffer_event *event; |
07d777fe | 2192 | int len = 0, size, pc; |
48ead020 | 2193 | struct print_entry *entry; |
07d777fe SR |
2194 | unsigned long flags; |
2195 | char *tbuffer; | |
48ead020 FW |
2196 | |
2197 | if (tracing_disabled || tracing_selftest_running) | |
2198 | return 0; | |
2199 | ||
07d777fe SR |
2200 | /* Don't pollute graph traces with trace_vprintk internals */ |
2201 | pause_graph_tracing(); | |
2202 | ||
48ead020 FW |
2203 | pc = preempt_count(); |
2204 | preempt_disable_notrace(); | |
48ead020 | 2205 | |
07d777fe SR |
2206 | |
2207 | tbuffer = get_trace_buf(); | |
2208 | if (!tbuffer) { | |
2209 | len = 0; | |
48ead020 | 2210 | goto out; |
07d777fe | 2211 | } |
48ead020 | 2212 | |
3558a5ac | 2213 | len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
48ead020 | 2214 | |
07d777fe | 2215 | local_save_flags(flags); |
48ead020 | 2216 | size = sizeof(*entry) + len + 1; |
e77405ad | 2217 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
07d777fe | 2218 | flags, pc); |
48ead020 | 2219 | if (!event) |
07d777fe | 2220 | goto out; |
48ead020 | 2221 | entry = ring_buffer_event_data(event); |
c13d2f7c | 2222 | entry->ip = ip; |
48ead020 | 2223 | |
3558a5ac | 2224 | memcpy(&entry->buf, tbuffer, len + 1); |
f306cc82 | 2225 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2226 | __buffer_unlock_commit(buffer, event); |
07d777fe | 2227 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 2228 | } |
48ead020 FW |
2229 | out: |
2230 | preempt_enable_notrace(); | |
07d777fe | 2231 | unpause_graph_tracing(); |
48ead020 FW |
2232 | |
2233 | return len; | |
2234 | } | |
659372d3 | 2235 | |
12883efb SRRH |
2236 | int trace_array_vprintk(struct trace_array *tr, |
2237 | unsigned long ip, const char *fmt, va_list args) | |
2238 | { | |
2239 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
2240 | } | |
2241 | ||
2242 | int trace_array_printk(struct trace_array *tr, | |
2243 | unsigned long ip, const char *fmt, ...) | |
2244 | { | |
2245 | int ret; | |
2246 | va_list ap; | |
2247 | ||
2248 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2249 | return 0; | |
2250 | ||
2251 | va_start(ap, fmt); | |
2252 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
2253 | va_end(ap); | |
2254 | return ret; | |
2255 | } | |
2256 | ||
2257 | int trace_array_printk_buf(struct ring_buffer *buffer, | |
2258 | unsigned long ip, const char *fmt, ...) | |
2259 | { | |
2260 | int ret; | |
2261 | va_list ap; | |
2262 | ||
2263 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2264 | return 0; | |
2265 | ||
2266 | va_start(ap, fmt); | |
2267 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
2268 | va_end(ap); | |
2269 | return ret; | |
2270 | } | |
2271 | ||
659372d3 SR |
2272 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
2273 | { | |
a813a159 | 2274 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 2275 | } |
769b0441 FW |
2276 | EXPORT_SYMBOL_GPL(trace_vprintk); |
2277 | ||
e2ac8ef5 | 2278 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 2279 | { |
6d158a81 SR |
2280 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
2281 | ||
5a90f577 | 2282 | iter->idx++; |
6d158a81 SR |
2283 | if (buf_iter) |
2284 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
2285 | } |
2286 | ||
e309b41d | 2287 | static struct trace_entry * |
bc21b478 SR |
2288 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
2289 | unsigned long *lost_events) | |
dd0e545f | 2290 | { |
3928a8a2 | 2291 | struct ring_buffer_event *event; |
6d158a81 | 2292 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 2293 | |
d769041f SR |
2294 | if (buf_iter) |
2295 | event = ring_buffer_iter_peek(buf_iter, ts); | |
2296 | else | |
12883efb | 2297 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 2298 | lost_events); |
d769041f | 2299 | |
4a9bd3f1 SR |
2300 | if (event) { |
2301 | iter->ent_size = ring_buffer_event_length(event); | |
2302 | return ring_buffer_event_data(event); | |
2303 | } | |
2304 | iter->ent_size = 0; | |
2305 | return NULL; | |
dd0e545f | 2306 | } |
d769041f | 2307 | |
dd0e545f | 2308 | static struct trace_entry * |
bc21b478 SR |
2309 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
2310 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 2311 | { |
12883efb | 2312 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 2313 | struct trace_entry *ent, *next = NULL; |
aa27497c | 2314 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 2315 | int cpu_file = iter->cpu_file; |
3928a8a2 | 2316 | u64 next_ts = 0, ts; |
bc0c38d1 | 2317 | int next_cpu = -1; |
12b5da34 | 2318 | int next_size = 0; |
bc0c38d1 SR |
2319 | int cpu; |
2320 | ||
b04cc6b1 FW |
2321 | /* |
2322 | * If we are in a per_cpu trace file, don't bother by iterating over | |
2323 | * all cpu and peek directly. | |
2324 | */ | |
ae3b5093 | 2325 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
2326 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
2327 | return NULL; | |
bc21b478 | 2328 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
2329 | if (ent_cpu) |
2330 | *ent_cpu = cpu_file; | |
2331 | ||
2332 | return ent; | |
2333 | } | |
2334 | ||
ab46428c | 2335 | for_each_tracing_cpu(cpu) { |
dd0e545f | 2336 | |
3928a8a2 SR |
2337 | if (ring_buffer_empty_cpu(buffer, cpu)) |
2338 | continue; | |
dd0e545f | 2339 | |
bc21b478 | 2340 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 2341 | |
cdd31cd2 IM |
2342 | /* |
2343 | * Pick the entry with the smallest timestamp: | |
2344 | */ | |
3928a8a2 | 2345 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
2346 | next = ent; |
2347 | next_cpu = cpu; | |
3928a8a2 | 2348 | next_ts = ts; |
bc21b478 | 2349 | next_lost = lost_events; |
12b5da34 | 2350 | next_size = iter->ent_size; |
bc0c38d1 SR |
2351 | } |
2352 | } | |
2353 | ||
12b5da34 SR |
2354 | iter->ent_size = next_size; |
2355 | ||
bc0c38d1 SR |
2356 | if (ent_cpu) |
2357 | *ent_cpu = next_cpu; | |
2358 | ||
3928a8a2 SR |
2359 | if (ent_ts) |
2360 | *ent_ts = next_ts; | |
2361 | ||
bc21b478 SR |
2362 | if (missing_events) |
2363 | *missing_events = next_lost; | |
2364 | ||
bc0c38d1 SR |
2365 | return next; |
2366 | } | |
2367 | ||
dd0e545f | 2368 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
2369 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
2370 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 2371 | { |
bc21b478 | 2372 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
2373 | } |
2374 | ||
2375 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 2376 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 2377 | { |
bc21b478 SR |
2378 | iter->ent = __find_next_entry(iter, &iter->cpu, |
2379 | &iter->lost_events, &iter->ts); | |
dd0e545f | 2380 | |
3928a8a2 | 2381 | if (iter->ent) |
e2ac8ef5 | 2382 | trace_iterator_increment(iter); |
dd0e545f | 2383 | |
3928a8a2 | 2384 | return iter->ent ? iter : NULL; |
b3806b43 | 2385 | } |
bc0c38d1 | 2386 | |
e309b41d | 2387 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 2388 | { |
12883efb | 2389 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 2390 | &iter->lost_events); |
bc0c38d1 SR |
2391 | } |
2392 | ||
e309b41d | 2393 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
2394 | { |
2395 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 2396 | int i = (int)*pos; |
4e3c3333 | 2397 | void *ent; |
bc0c38d1 | 2398 | |
a63ce5b3 SR |
2399 | WARN_ON_ONCE(iter->leftover); |
2400 | ||
bc0c38d1 SR |
2401 | (*pos)++; |
2402 | ||
2403 | /* can't go backwards */ | |
2404 | if (iter->idx > i) | |
2405 | return NULL; | |
2406 | ||
2407 | if (iter->idx < 0) | |
955b61e5 | 2408 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2409 | else |
2410 | ent = iter; | |
2411 | ||
2412 | while (ent && iter->idx < i) | |
955b61e5 | 2413 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2414 | |
2415 | iter->pos = *pos; | |
2416 | ||
bc0c38d1 SR |
2417 | return ent; |
2418 | } | |
2419 | ||
955b61e5 | 2420 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 2421 | { |
2f26ebd5 SR |
2422 | struct ring_buffer_event *event; |
2423 | struct ring_buffer_iter *buf_iter; | |
2424 | unsigned long entries = 0; | |
2425 | u64 ts; | |
2426 | ||
12883efb | 2427 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 2428 | |
6d158a81 SR |
2429 | buf_iter = trace_buffer_iter(iter, cpu); |
2430 | if (!buf_iter) | |
2f26ebd5 SR |
2431 | return; |
2432 | ||
2f26ebd5 SR |
2433 | ring_buffer_iter_reset(buf_iter); |
2434 | ||
2435 | /* | |
2436 | * We could have the case with the max latency tracers | |
2437 | * that a reset never took place on a cpu. This is evident | |
2438 | * by the timestamp being before the start of the buffer. | |
2439 | */ | |
2440 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 2441 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
2442 | break; |
2443 | entries++; | |
2444 | ring_buffer_read(buf_iter, NULL); | |
2445 | } | |
2446 | ||
12883efb | 2447 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2448 | } |
2449 | ||
d7350c3f | 2450 | /* |
d7350c3f FW |
2451 | * The current tracer is copied to avoid a global locking |
2452 | * all around. | |
2453 | */ | |
bc0c38d1 SR |
2454 | static void *s_start(struct seq_file *m, loff_t *pos) |
2455 | { | |
2456 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2457 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2458 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2459 | void *p = NULL; |
2460 | loff_t l = 0; | |
3928a8a2 | 2461 | int cpu; |
bc0c38d1 | 2462 | |
2fd196ec HT |
2463 | /* |
2464 | * copy the tracer to avoid using a global lock all around. | |
2465 | * iter->trace is a copy of current_trace, the pointer to the | |
2466 | * name may be used instead of a strcmp(), as iter->trace->name | |
2467 | * will point to the same string as current_trace->name. | |
2468 | */ | |
bc0c38d1 | 2469 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2470 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2471 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2472 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2473 | |
12883efb | 2474 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2475 | if (iter->snapshot && iter->trace->use_max_tr) |
2476 | return ERR_PTR(-EBUSY); | |
12883efb | 2477 | #endif |
debdd57f HT |
2478 | |
2479 | if (!iter->snapshot) | |
2480 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2481 | |
bc0c38d1 SR |
2482 | if (*pos != iter->pos) { |
2483 | iter->ent = NULL; | |
2484 | iter->cpu = 0; | |
2485 | iter->idx = -1; | |
2486 | ||
ae3b5093 | 2487 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2488 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2489 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2490 | } else |
2f26ebd5 | 2491 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2492 | |
ac91d854 | 2493 | iter->leftover = 0; |
bc0c38d1 SR |
2494 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2495 | ; | |
2496 | ||
2497 | } else { | |
a63ce5b3 SR |
2498 | /* |
2499 | * If we overflowed the seq_file before, then we want | |
2500 | * to just reuse the trace_seq buffer again. | |
2501 | */ | |
2502 | if (iter->leftover) | |
2503 | p = iter; | |
2504 | else { | |
2505 | l = *pos - 1; | |
2506 | p = s_next(m, p, &l); | |
2507 | } | |
bc0c38d1 SR |
2508 | } |
2509 | ||
4f535968 | 2510 | trace_event_read_lock(); |
7e53bd42 | 2511 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2512 | return p; |
2513 | } | |
2514 | ||
2515 | static void s_stop(struct seq_file *m, void *p) | |
2516 | { | |
7e53bd42 LJ |
2517 | struct trace_iterator *iter = m->private; |
2518 | ||
12883efb | 2519 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2520 | if (iter->snapshot && iter->trace->use_max_tr) |
2521 | return; | |
12883efb | 2522 | #endif |
debdd57f HT |
2523 | |
2524 | if (!iter->snapshot) | |
2525 | atomic_dec(&trace_record_cmdline_disabled); | |
12883efb | 2526 | |
7e53bd42 | 2527 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2528 | trace_event_read_unlock(); |
bc0c38d1 SR |
2529 | } |
2530 | ||
39eaf7ef | 2531 | static void |
12883efb SRRH |
2532 | get_total_entries(struct trace_buffer *buf, |
2533 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
2534 | { |
2535 | unsigned long count; | |
2536 | int cpu; | |
2537 | ||
2538 | *total = 0; | |
2539 | *entries = 0; | |
2540 | ||
2541 | for_each_tracing_cpu(cpu) { | |
12883efb | 2542 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2543 | /* |
2544 | * If this buffer has skipped entries, then we hold all | |
2545 | * entries for the trace and we need to ignore the | |
2546 | * ones before the time stamp. | |
2547 | */ | |
12883efb SRRH |
2548 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
2549 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2550 | /* total is the same as the entries */ |
2551 | *total += count; | |
2552 | } else | |
2553 | *total += count + | |
12883efb | 2554 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2555 | *entries += count; |
2556 | } | |
2557 | } | |
2558 | ||
e309b41d | 2559 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2560 | { |
d79ac28f RV |
2561 | seq_puts(m, "# _------=> CPU# \n" |
2562 | "# / _-----=> irqs-off \n" | |
2563 | "# | / _----=> need-resched \n" | |
2564 | "# || / _---=> hardirq/softirq \n" | |
2565 | "# ||| / _--=> preempt-depth \n" | |
2566 | "# |||| / delay \n" | |
2567 | "# cmd pid ||||| time | caller \n" | |
2568 | "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2569 | } |
2570 | ||
12883efb | 2571 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 2572 | { |
39eaf7ef SR |
2573 | unsigned long total; |
2574 | unsigned long entries; | |
2575 | ||
12883efb | 2576 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
2577 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
2578 | entries, total, num_online_cpus()); | |
2579 | seq_puts(m, "#\n"); | |
2580 | } | |
2581 | ||
12883efb | 2582 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) |
39eaf7ef | 2583 | { |
12883efb | 2584 | print_event_info(buf, m); |
d79ac28f RV |
2585 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n" |
2586 | "# | | | | |\n"); | |
bc0c38d1 SR |
2587 | } |
2588 | ||
12883efb | 2589 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) |
77271ce4 | 2590 | { |
12883efb | 2591 | print_event_info(buf, m); |
d79ac28f RV |
2592 | seq_puts(m, "# _-----=> irqs-off\n" |
2593 | "# / _----=> need-resched\n" | |
2594 | "# | / _---=> hardirq/softirq\n" | |
2595 | "# || / _--=> preempt-depth\n" | |
2596 | "# ||| / delay\n" | |
2597 | "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n" | |
2598 | "# | | | |||| | |\n"); | |
77271ce4 | 2599 | } |
bc0c38d1 | 2600 | |
62b915f1 | 2601 | void |
bc0c38d1 SR |
2602 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2603 | { | |
2604 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
12883efb SRRH |
2605 | struct trace_buffer *buf = iter->trace_buffer; |
2606 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 2607 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2608 | unsigned long entries; |
2609 | unsigned long total; | |
bc0c38d1 SR |
2610 | const char *name = "preemption"; |
2611 | ||
d840f718 | 2612 | name = type->name; |
bc0c38d1 | 2613 | |
12883efb | 2614 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 2615 | |
888b55dc | 2616 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2617 | name, UTS_RELEASE); |
888b55dc | 2618 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2619 | "---------------------------------\n"); |
888b55dc | 2620 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2621 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2622 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2623 | entries, |
4c11d7ae | 2624 | total, |
12883efb | 2625 | buf->cpu, |
bc0c38d1 SR |
2626 | #if defined(CONFIG_PREEMPT_NONE) |
2627 | "server", | |
2628 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2629 | "desktop", | |
b5c21b45 | 2630 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2631 | "preempt", |
2632 | #else | |
2633 | "unknown", | |
2634 | #endif | |
2635 | /* These are reserved for later use */ | |
2636 | 0, 0, 0, 0); | |
2637 | #ifdef CONFIG_SMP | |
2638 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2639 | #else | |
2640 | seq_puts(m, ")\n"); | |
2641 | #endif | |
888b55dc KM |
2642 | seq_puts(m, "# -----------------\n"); |
2643 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2644 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2645 | data->comm, data->pid, |
2646 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2647 | data->policy, data->rt_priority); |
888b55dc | 2648 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2649 | |
2650 | if (data->critical_start) { | |
888b55dc | 2651 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2652 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2653 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2654 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2655 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2656 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2657 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2658 | } |
2659 | ||
888b55dc | 2660 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2661 | } |
2662 | ||
a309720c SR |
2663 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2664 | { | |
2665 | struct trace_seq *s = &iter->seq; | |
2666 | ||
12ef7d44 SR |
2667 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2668 | return; | |
2669 | ||
2670 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2671 | return; | |
2672 | ||
4462344e | 2673 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2674 | return; |
2675 | ||
12883efb | 2676 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
2677 | return; |
2678 | ||
4462344e | 2679 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2680 | |
2681 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2682 | if (iter->idx > 1) | |
2683 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2684 | iter->cpu); | |
a309720c SR |
2685 | } |
2686 | ||
2c4f035f | 2687 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2688 | { |
214023c3 | 2689 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2690 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2691 | struct trace_entry *entry; |
f633cef0 | 2692 | struct trace_event *event; |
bc0c38d1 | 2693 | |
4e3c3333 | 2694 | entry = iter->ent; |
dd0e545f | 2695 | |
a309720c SR |
2696 | test_cpu_buff_start(iter); |
2697 | ||
c4a8e8be | 2698 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2699 | |
c4a8e8be | 2700 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
2701 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) |
2702 | trace_print_lat_context(iter); | |
2703 | else | |
2704 | trace_print_context(iter); | |
c4a8e8be | 2705 | } |
bc0c38d1 | 2706 | |
19a7fe20 SRRH |
2707 | if (trace_seq_has_overflowed(s)) |
2708 | return TRACE_TYPE_PARTIAL_LINE; | |
2709 | ||
268ccda0 | 2710 | if (event) |
a9a57763 | 2711 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 | 2712 | |
19a7fe20 | 2713 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
02b67518 | 2714 | |
19a7fe20 | 2715 | return trace_handle_return(s); |
bc0c38d1 SR |
2716 | } |
2717 | ||
2c4f035f | 2718 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2719 | { |
2720 | struct trace_seq *s = &iter->seq; | |
2721 | struct trace_entry *entry; | |
f633cef0 | 2722 | struct trace_event *event; |
f9896bf3 IM |
2723 | |
2724 | entry = iter->ent; | |
dd0e545f | 2725 | |
19a7fe20 SRRH |
2726 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) |
2727 | trace_seq_printf(s, "%d %d %llu ", | |
2728 | entry->pid, iter->cpu, iter->ts); | |
2729 | ||
2730 | if (trace_seq_has_overflowed(s)) | |
2731 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 | 2732 | |
f633cef0 | 2733 | event = ftrace_find_event(entry->type); |
268ccda0 | 2734 | if (event) |
a9a57763 | 2735 | return event->funcs->raw(iter, 0, event); |
d9793bd8 | 2736 | |
19a7fe20 | 2737 | trace_seq_printf(s, "%d ?\n", entry->type); |
777e208d | 2738 | |
19a7fe20 | 2739 | return trace_handle_return(s); |
f9896bf3 IM |
2740 | } |
2741 | ||
2c4f035f | 2742 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2743 | { |
2744 | struct trace_seq *s = &iter->seq; | |
2745 | unsigned char newline = '\n'; | |
2746 | struct trace_entry *entry; | |
f633cef0 | 2747 | struct trace_event *event; |
5e3ca0ec IM |
2748 | |
2749 | entry = iter->ent; | |
dd0e545f | 2750 | |
c4a8e8be | 2751 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
2752 | SEQ_PUT_HEX_FIELD(s, entry->pid); |
2753 | SEQ_PUT_HEX_FIELD(s, iter->cpu); | |
2754 | SEQ_PUT_HEX_FIELD(s, iter->ts); | |
2755 | if (trace_seq_has_overflowed(s)) | |
2756 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 2757 | } |
5e3ca0ec | 2758 | |
f633cef0 | 2759 | event = ftrace_find_event(entry->type); |
268ccda0 | 2760 | if (event) { |
a9a57763 | 2761 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2762 | if (ret != TRACE_TYPE_HANDLED) |
2763 | return ret; | |
2764 | } | |
7104f300 | 2765 | |
19a7fe20 | 2766 | SEQ_PUT_FIELD(s, newline); |
5e3ca0ec | 2767 | |
19a7fe20 | 2768 | return trace_handle_return(s); |
5e3ca0ec IM |
2769 | } |
2770 | ||
2c4f035f | 2771 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2772 | { |
2773 | struct trace_seq *s = &iter->seq; | |
2774 | struct trace_entry *entry; | |
f633cef0 | 2775 | struct trace_event *event; |
cb0f12aa IM |
2776 | |
2777 | entry = iter->ent; | |
dd0e545f | 2778 | |
c4a8e8be | 2779 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
2780 | SEQ_PUT_FIELD(s, entry->pid); |
2781 | SEQ_PUT_FIELD(s, iter->cpu); | |
2782 | SEQ_PUT_FIELD(s, iter->ts); | |
2783 | if (trace_seq_has_overflowed(s)) | |
2784 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 2785 | } |
cb0f12aa | 2786 | |
f633cef0 | 2787 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2788 | return event ? event->funcs->binary(iter, 0, event) : |
2789 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2790 | } |
2791 | ||
62b915f1 | 2792 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2793 | { |
6d158a81 | 2794 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
2795 | int cpu; |
2796 | ||
9aba60fe | 2797 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 2798 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 2799 | cpu = iter->cpu_file; |
6d158a81 SR |
2800 | buf_iter = trace_buffer_iter(iter, cpu); |
2801 | if (buf_iter) { | |
2802 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
2803 | return 0; |
2804 | } else { | |
12883efb | 2805 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
2806 | return 0; |
2807 | } | |
2808 | return 1; | |
2809 | } | |
2810 | ||
ab46428c | 2811 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
2812 | buf_iter = trace_buffer_iter(iter, cpu); |
2813 | if (buf_iter) { | |
2814 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
2815 | return 0; |
2816 | } else { | |
12883efb | 2817 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
2818 | return 0; |
2819 | } | |
bc0c38d1 | 2820 | } |
d769041f | 2821 | |
797d3712 | 2822 | return 1; |
bc0c38d1 SR |
2823 | } |
2824 | ||
4f535968 | 2825 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2826 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2827 | { |
2c4f035f FW |
2828 | enum print_line_t ret; |
2829 | ||
19a7fe20 SRRH |
2830 | if (iter->lost_events) { |
2831 | trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2832 | iter->cpu, iter->lost_events); | |
2833 | if (trace_seq_has_overflowed(&iter->seq)) | |
2834 | return TRACE_TYPE_PARTIAL_LINE; | |
2835 | } | |
bc21b478 | 2836 | |
2c4f035f FW |
2837 | if (iter->trace && iter->trace->print_line) { |
2838 | ret = iter->trace->print_line(iter); | |
2839 | if (ret != TRACE_TYPE_UNHANDLED) | |
2840 | return ret; | |
2841 | } | |
72829bc3 | 2842 | |
09ae7234 SRRH |
2843 | if (iter->ent->type == TRACE_BPUTS && |
2844 | trace_flags & TRACE_ITER_PRINTK && | |
2845 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
2846 | return trace_print_bputs_msg_only(iter); | |
2847 | ||
48ead020 FW |
2848 | if (iter->ent->type == TRACE_BPRINT && |
2849 | trace_flags & TRACE_ITER_PRINTK && | |
2850 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2851 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2852 | |
66896a85 FW |
2853 | if (iter->ent->type == TRACE_PRINT && |
2854 | trace_flags & TRACE_ITER_PRINTK && | |
2855 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2856 | return trace_print_printk_msg_only(iter); |
66896a85 | 2857 | |
cb0f12aa IM |
2858 | if (trace_flags & TRACE_ITER_BIN) |
2859 | return print_bin_fmt(iter); | |
2860 | ||
5e3ca0ec IM |
2861 | if (trace_flags & TRACE_ITER_HEX) |
2862 | return print_hex_fmt(iter); | |
2863 | ||
f9896bf3 IM |
2864 | if (trace_flags & TRACE_ITER_RAW) |
2865 | return print_raw_fmt(iter); | |
2866 | ||
f9896bf3 IM |
2867 | return print_trace_fmt(iter); |
2868 | } | |
2869 | ||
7e9a49ef JO |
2870 | void trace_latency_header(struct seq_file *m) |
2871 | { | |
2872 | struct trace_iterator *iter = m->private; | |
2873 | ||
2874 | /* print nothing if the buffers are empty */ | |
2875 | if (trace_empty(iter)) | |
2876 | return; | |
2877 | ||
2878 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2879 | print_trace_header(m, iter); | |
2880 | ||
2881 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2882 | print_lat_help_header(m); | |
2883 | } | |
2884 | ||
62b915f1 JO |
2885 | void trace_default_header(struct seq_file *m) |
2886 | { | |
2887 | struct trace_iterator *iter = m->private; | |
2888 | ||
f56e7f8e JO |
2889 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2890 | return; | |
2891 | ||
62b915f1 JO |
2892 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2893 | /* print nothing if the buffers are empty */ | |
2894 | if (trace_empty(iter)) | |
2895 | return; | |
2896 | print_trace_header(m, iter); | |
2897 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2898 | print_lat_help_header(m); | |
2899 | } else { | |
77271ce4 SR |
2900 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2901 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
12883efb | 2902 | print_func_help_header_irq(iter->trace_buffer, m); |
77271ce4 | 2903 | else |
12883efb | 2904 | print_func_help_header(iter->trace_buffer, m); |
77271ce4 | 2905 | } |
62b915f1 JO |
2906 | } |
2907 | } | |
2908 | ||
e0a413f6 SR |
2909 | static void test_ftrace_alive(struct seq_file *m) |
2910 | { | |
2911 | if (!ftrace_is_dead()) | |
2912 | return; | |
d79ac28f RV |
2913 | seq_puts(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n" |
2914 | "# MAY BE MISSING FUNCTION EVENTS\n"); | |
e0a413f6 SR |
2915 | } |
2916 | ||
d8741e2e | 2917 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 2918 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 2919 | { |
d79ac28f RV |
2920 | seq_puts(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n" |
2921 | "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" | |
2922 | "# Takes a snapshot of the main buffer.\n" | |
2923 | "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n" | |
2924 | "# (Doesn't have to be '2' works with any number that\n" | |
2925 | "# is not a '0' or '1')\n"); | |
d8741e2e | 2926 | } |
f1affcaa SRRH |
2927 | |
2928 | static void show_snapshot_percpu_help(struct seq_file *m) | |
2929 | { | |
fa6f0cc7 | 2930 | seq_puts(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); |
f1affcaa | 2931 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP |
d79ac28f RV |
2932 | seq_puts(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" |
2933 | "# Takes a snapshot of the main buffer for this cpu.\n"); | |
f1affcaa | 2934 | #else |
d79ac28f RV |
2935 | seq_puts(m, "# echo 1 > snapshot : Not supported with this kernel.\n" |
2936 | "# Must use main snapshot file to allocate.\n"); | |
f1affcaa | 2937 | #endif |
d79ac28f RV |
2938 | seq_puts(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n" |
2939 | "# (Doesn't have to be '2' works with any number that\n" | |
2940 | "# is not a '0' or '1')\n"); | |
f1affcaa SRRH |
2941 | } |
2942 | ||
d8741e2e SRRH |
2943 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
2944 | { | |
45ad21ca | 2945 | if (iter->tr->allocated_snapshot) |
fa6f0cc7 | 2946 | seq_puts(m, "#\n# * Snapshot is allocated *\n#\n"); |
d8741e2e | 2947 | else |
fa6f0cc7 | 2948 | seq_puts(m, "#\n# * Snapshot is freed *\n#\n"); |
d8741e2e | 2949 | |
fa6f0cc7 | 2950 | seq_puts(m, "# Snapshot commands:\n"); |
f1affcaa SRRH |
2951 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
2952 | show_snapshot_main_help(m); | |
2953 | else | |
2954 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
2955 | } |
2956 | #else | |
2957 | /* Should never be called */ | |
2958 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
2959 | #endif | |
2960 | ||
bc0c38d1 SR |
2961 | static int s_show(struct seq_file *m, void *v) |
2962 | { | |
2963 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2964 | int ret; |
bc0c38d1 SR |
2965 | |
2966 | if (iter->ent == NULL) { | |
2967 | if (iter->tr) { | |
2968 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2969 | seq_puts(m, "#\n"); | |
e0a413f6 | 2970 | test_ftrace_alive(m); |
bc0c38d1 | 2971 | } |
d8741e2e SRRH |
2972 | if (iter->snapshot && trace_empty(iter)) |
2973 | print_snapshot_help(m, iter); | |
2974 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 2975 | iter->trace->print_header(m); |
62b915f1 JO |
2976 | else |
2977 | trace_default_header(m); | |
2978 | ||
a63ce5b3 SR |
2979 | } else if (iter->leftover) { |
2980 | /* | |
2981 | * If we filled the seq_file buffer earlier, we | |
2982 | * want to just show it now. | |
2983 | */ | |
2984 | ret = trace_print_seq(m, &iter->seq); | |
2985 | ||
2986 | /* ret should this time be zero, but you never know */ | |
2987 | iter->leftover = ret; | |
2988 | ||
bc0c38d1 | 2989 | } else { |
f9896bf3 | 2990 | print_trace_line(iter); |
a63ce5b3 SR |
2991 | ret = trace_print_seq(m, &iter->seq); |
2992 | /* | |
2993 | * If we overflow the seq_file buffer, then it will | |
2994 | * ask us for this data again at start up. | |
2995 | * Use that instead. | |
2996 | * ret is 0 if seq_file write succeeded. | |
2997 | * -1 otherwise. | |
2998 | */ | |
2999 | iter->leftover = ret; | |
bc0c38d1 SR |
3000 | } |
3001 | ||
3002 | return 0; | |
3003 | } | |
3004 | ||
649e9c70 ON |
3005 | /* |
3006 | * Should be used after trace_array_get(), trace_types_lock | |
3007 | * ensures that i_cdev was already initialized. | |
3008 | */ | |
3009 | static inline int tracing_get_cpu(struct inode *inode) | |
3010 | { | |
3011 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
3012 | return (long)inode->i_cdev - 1; | |
3013 | return RING_BUFFER_ALL_CPUS; | |
3014 | } | |
3015 | ||
88e9d34c | 3016 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
3017 | .start = s_start, |
3018 | .next = s_next, | |
3019 | .stop = s_stop, | |
3020 | .show = s_show, | |
bc0c38d1 SR |
3021 | }; |
3022 | ||
e309b41d | 3023 | static struct trace_iterator * |
6484c71c | 3024 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 3025 | { |
6484c71c | 3026 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 3027 | struct trace_iterator *iter; |
50e18b94 | 3028 | int cpu; |
bc0c38d1 | 3029 | |
85a2f9b4 SR |
3030 | if (tracing_disabled) |
3031 | return ERR_PTR(-ENODEV); | |
60a11774 | 3032 | |
50e18b94 | 3033 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
3034 | if (!iter) |
3035 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 3036 | |
6d158a81 SR |
3037 | iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(), |
3038 | GFP_KERNEL); | |
93574fcc DC |
3039 | if (!iter->buffer_iter) |
3040 | goto release; | |
3041 | ||
d7350c3f FW |
3042 | /* |
3043 | * We make a copy of the current tracer to avoid concurrent | |
3044 | * changes on it while we are reading. | |
3045 | */ | |
bc0c38d1 | 3046 | mutex_lock(&trace_types_lock); |
d7350c3f | 3047 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 3048 | if (!iter->trace) |
d7350c3f | 3049 | goto fail; |
85a2f9b4 | 3050 | |
2b6080f2 | 3051 | *iter->trace = *tr->current_trace; |
d7350c3f | 3052 | |
79f55997 | 3053 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
3054 | goto fail; |
3055 | ||
12883efb SRRH |
3056 | iter->tr = tr; |
3057 | ||
3058 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
3059 | /* Currently only the top directory has a snapshot */ |
3060 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 3061 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 3062 | else |
12883efb SRRH |
3063 | #endif |
3064 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 3065 | iter->snapshot = snapshot; |
bc0c38d1 | 3066 | iter->pos = -1; |
6484c71c | 3067 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 3068 | mutex_init(&iter->mutex); |
bc0c38d1 | 3069 | |
8bba1bf5 MM |
3070 | /* Notify the tracer early; before we stop tracing. */ |
3071 | if (iter->trace && iter->trace->open) | |
a93751ca | 3072 | iter->trace->open(iter); |
8bba1bf5 | 3073 | |
12ef7d44 | 3074 | /* Annotate start of buffers if we had overruns */ |
12883efb | 3075 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
3076 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
3077 | ||
8be0709f | 3078 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 3079 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
3080 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
3081 | ||
debdd57f HT |
3082 | /* stop the trace while dumping if we are not opening "snapshot" */ |
3083 | if (!iter->snapshot) | |
2b6080f2 | 3084 | tracing_stop_tr(tr); |
2f26ebd5 | 3085 | |
ae3b5093 | 3086 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 3087 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 3088 | iter->buffer_iter[cpu] = |
12883efb | 3089 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3090 | } |
3091 | ring_buffer_read_prepare_sync(); | |
3092 | for_each_tracing_cpu(cpu) { | |
3093 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3094 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
3095 | } |
3096 | } else { | |
3097 | cpu = iter->cpu_file; | |
3928a8a2 | 3098 | iter->buffer_iter[cpu] = |
12883efb | 3099 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3100 | ring_buffer_read_prepare_sync(); |
3101 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3102 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
3103 | } |
3104 | ||
bc0c38d1 SR |
3105 | mutex_unlock(&trace_types_lock); |
3106 | ||
bc0c38d1 | 3107 | return iter; |
3928a8a2 | 3108 | |
d7350c3f | 3109 | fail: |
3928a8a2 | 3110 | mutex_unlock(&trace_types_lock); |
d7350c3f | 3111 | kfree(iter->trace); |
6d158a81 | 3112 | kfree(iter->buffer_iter); |
93574fcc | 3113 | release: |
50e18b94 JO |
3114 | seq_release_private(inode, file); |
3115 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
3116 | } |
3117 | ||
3118 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
3119 | { | |
60a11774 SR |
3120 | if (tracing_disabled) |
3121 | return -ENODEV; | |
3122 | ||
bc0c38d1 SR |
3123 | filp->private_data = inode->i_private; |
3124 | return 0; | |
3125 | } | |
3126 | ||
2e86421d GB |
3127 | bool tracing_is_disabled(void) |
3128 | { | |
3129 | return (tracing_disabled) ? true: false; | |
3130 | } | |
3131 | ||
7b85af63 SRRH |
3132 | /* |
3133 | * Open and update trace_array ref count. | |
3134 | * Must have the current trace_array passed to it. | |
3135 | */ | |
dcc30223 | 3136 | static int tracing_open_generic_tr(struct inode *inode, struct file *filp) |
7b85af63 SRRH |
3137 | { |
3138 | struct trace_array *tr = inode->i_private; | |
3139 | ||
3140 | if (tracing_disabled) | |
3141 | return -ENODEV; | |
3142 | ||
3143 | if (trace_array_get(tr) < 0) | |
3144 | return -ENODEV; | |
3145 | ||
3146 | filp->private_data = inode->i_private; | |
3147 | ||
3148 | return 0; | |
7b85af63 SRRH |
3149 | } |
3150 | ||
4fd27358 | 3151 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 3152 | { |
6484c71c | 3153 | struct trace_array *tr = inode->i_private; |
907f2784 | 3154 | struct seq_file *m = file->private_data; |
4acd4d00 | 3155 | struct trace_iterator *iter; |
3928a8a2 | 3156 | int cpu; |
bc0c38d1 | 3157 | |
ff451961 | 3158 | if (!(file->f_mode & FMODE_READ)) { |
6484c71c | 3159 | trace_array_put(tr); |
4acd4d00 | 3160 | return 0; |
ff451961 | 3161 | } |
4acd4d00 | 3162 | |
6484c71c | 3163 | /* Writes do not use seq_file */ |
4acd4d00 | 3164 | iter = m->private; |
bc0c38d1 | 3165 | mutex_lock(&trace_types_lock); |
a695cb58 | 3166 | |
3928a8a2 SR |
3167 | for_each_tracing_cpu(cpu) { |
3168 | if (iter->buffer_iter[cpu]) | |
3169 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
3170 | } | |
3171 | ||
bc0c38d1 SR |
3172 | if (iter->trace && iter->trace->close) |
3173 | iter->trace->close(iter); | |
3174 | ||
debdd57f HT |
3175 | if (!iter->snapshot) |
3176 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 3177 | tracing_start_tr(tr); |
f77d09a3 AL |
3178 | |
3179 | __trace_array_put(tr); | |
3180 | ||
bc0c38d1 SR |
3181 | mutex_unlock(&trace_types_lock); |
3182 | ||
d7350c3f | 3183 | mutex_destroy(&iter->mutex); |
b0dfa978 | 3184 | free_cpumask_var(iter->started); |
d7350c3f | 3185 | kfree(iter->trace); |
6d158a81 | 3186 | kfree(iter->buffer_iter); |
50e18b94 | 3187 | seq_release_private(inode, file); |
ff451961 | 3188 | |
bc0c38d1 SR |
3189 | return 0; |
3190 | } | |
3191 | ||
7b85af63 SRRH |
3192 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
3193 | { | |
3194 | struct trace_array *tr = inode->i_private; | |
3195 | ||
3196 | trace_array_put(tr); | |
bc0c38d1 SR |
3197 | return 0; |
3198 | } | |
3199 | ||
7b85af63 SRRH |
3200 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
3201 | { | |
3202 | struct trace_array *tr = inode->i_private; | |
3203 | ||
3204 | trace_array_put(tr); | |
3205 | ||
3206 | return single_release(inode, file); | |
3207 | } | |
3208 | ||
bc0c38d1 SR |
3209 | static int tracing_open(struct inode *inode, struct file *file) |
3210 | { | |
6484c71c | 3211 | struct trace_array *tr = inode->i_private; |
85a2f9b4 SR |
3212 | struct trace_iterator *iter; |
3213 | int ret = 0; | |
bc0c38d1 | 3214 | |
ff451961 SRRH |
3215 | if (trace_array_get(tr) < 0) |
3216 | return -ENODEV; | |
3217 | ||
4acd4d00 | 3218 | /* If this file was open for write, then erase contents */ |
6484c71c ON |
3219 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
3220 | int cpu = tracing_get_cpu(inode); | |
3221 | ||
3222 | if (cpu == RING_BUFFER_ALL_CPUS) | |
12883efb | 3223 | tracing_reset_online_cpus(&tr->trace_buffer); |
4acd4d00 | 3224 | else |
6484c71c | 3225 | tracing_reset(&tr->trace_buffer, cpu); |
4acd4d00 | 3226 | } |
bc0c38d1 | 3227 | |
4acd4d00 | 3228 | if (file->f_mode & FMODE_READ) { |
6484c71c | 3229 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
3230 | if (IS_ERR(iter)) |
3231 | ret = PTR_ERR(iter); | |
3232 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
3233 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3234 | } | |
ff451961 SRRH |
3235 | |
3236 | if (ret < 0) | |
3237 | trace_array_put(tr); | |
3238 | ||
bc0c38d1 SR |
3239 | return ret; |
3240 | } | |
3241 | ||
607e2ea1 SRRH |
3242 | /* |
3243 | * Some tracers are not suitable for instance buffers. | |
3244 | * A tracer is always available for the global array (toplevel) | |
3245 | * or if it explicitly states that it is. | |
3246 | */ | |
3247 | static bool | |
3248 | trace_ok_for_array(struct tracer *t, struct trace_array *tr) | |
3249 | { | |
3250 | return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; | |
3251 | } | |
3252 | ||
3253 | /* Find the next tracer that this trace array may use */ | |
3254 | static struct tracer * | |
3255 | get_tracer_for_array(struct trace_array *tr, struct tracer *t) | |
3256 | { | |
3257 | while (t && !trace_ok_for_array(t, tr)) | |
3258 | t = t->next; | |
3259 | ||
3260 | return t; | |
3261 | } | |
3262 | ||
e309b41d | 3263 | static void * |
bc0c38d1 SR |
3264 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3265 | { | |
607e2ea1 | 3266 | struct trace_array *tr = m->private; |
f129e965 | 3267 | struct tracer *t = v; |
bc0c38d1 SR |
3268 | |
3269 | (*pos)++; | |
3270 | ||
3271 | if (t) | |
607e2ea1 | 3272 | t = get_tracer_for_array(tr, t->next); |
bc0c38d1 | 3273 | |
bc0c38d1 SR |
3274 | return t; |
3275 | } | |
3276 | ||
3277 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3278 | { | |
607e2ea1 | 3279 | struct trace_array *tr = m->private; |
f129e965 | 3280 | struct tracer *t; |
bc0c38d1 SR |
3281 | loff_t l = 0; |
3282 | ||
3283 | mutex_lock(&trace_types_lock); | |
607e2ea1 SRRH |
3284 | |
3285 | t = get_tracer_for_array(tr, trace_types); | |
3286 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
3287 | ; | |
bc0c38d1 SR |
3288 | |
3289 | return t; | |
3290 | } | |
3291 | ||
3292 | static void t_stop(struct seq_file *m, void *p) | |
3293 | { | |
3294 | mutex_unlock(&trace_types_lock); | |
3295 | } | |
3296 | ||
3297 | static int t_show(struct seq_file *m, void *v) | |
3298 | { | |
3299 | struct tracer *t = v; | |
3300 | ||
3301 | if (!t) | |
3302 | return 0; | |
3303 | ||
fa6f0cc7 | 3304 | seq_puts(m, t->name); |
bc0c38d1 SR |
3305 | if (t->next) |
3306 | seq_putc(m, ' '); | |
3307 | else | |
3308 | seq_putc(m, '\n'); | |
3309 | ||
3310 | return 0; | |
3311 | } | |
3312 | ||
88e9d34c | 3313 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
3314 | .start = t_start, |
3315 | .next = t_next, | |
3316 | .stop = t_stop, | |
3317 | .show = t_show, | |
bc0c38d1 SR |
3318 | }; |
3319 | ||
3320 | static int show_traces_open(struct inode *inode, struct file *file) | |
3321 | { | |
607e2ea1 SRRH |
3322 | struct trace_array *tr = inode->i_private; |
3323 | struct seq_file *m; | |
3324 | int ret; | |
3325 | ||
60a11774 SR |
3326 | if (tracing_disabled) |
3327 | return -ENODEV; | |
3328 | ||
607e2ea1 SRRH |
3329 | ret = seq_open(file, &show_traces_seq_ops); |
3330 | if (ret) | |
3331 | return ret; | |
3332 | ||
3333 | m = file->private_data; | |
3334 | m->private = tr; | |
3335 | ||
3336 | return 0; | |
bc0c38d1 SR |
3337 | } |
3338 | ||
4acd4d00 SR |
3339 | static ssize_t |
3340 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
3341 | size_t count, loff_t *ppos) | |
3342 | { | |
3343 | return count; | |
3344 | } | |
3345 | ||
098c879e | 3346 | loff_t tracing_lseek(struct file *file, loff_t offset, int whence) |
364829b1 | 3347 | { |
098c879e SRRH |
3348 | int ret; |
3349 | ||
364829b1 | 3350 | if (file->f_mode & FMODE_READ) |
098c879e | 3351 | ret = seq_lseek(file, offset, whence); |
364829b1 | 3352 | else |
098c879e SRRH |
3353 | file->f_pos = ret = 0; |
3354 | ||
3355 | return ret; | |
364829b1 SP |
3356 | } |
3357 | ||
5e2336a0 | 3358 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
3359 | .open = tracing_open, |
3360 | .read = seq_read, | |
4acd4d00 | 3361 | .write = tracing_write_stub, |
098c879e | 3362 | .llseek = tracing_lseek, |
4bf39a94 | 3363 | .release = tracing_release, |
bc0c38d1 SR |
3364 | }; |
3365 | ||
5e2336a0 | 3366 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
3367 | .open = show_traces_open, |
3368 | .read = seq_read, | |
3369 | .release = seq_release, | |
b444786f | 3370 | .llseek = seq_lseek, |
c7078de1 IM |
3371 | }; |
3372 | ||
36dfe925 IM |
3373 | /* |
3374 | * The tracer itself will not take this lock, but still we want | |
3375 | * to provide a consistent cpumask to user-space: | |
3376 | */ | |
3377 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
3378 | ||
3379 | /* | |
3380 | * Temporary storage for the character representation of the | |
3381 | * CPU bitmask (and one more byte for the newline): | |
3382 | */ | |
3383 | static char mask_str[NR_CPUS + 1]; | |
3384 | ||
c7078de1 IM |
3385 | static ssize_t |
3386 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
3387 | size_t count, loff_t *ppos) | |
3388 | { | |
ccfe9e42 | 3389 | struct trace_array *tr = file_inode(filp)->i_private; |
36dfe925 | 3390 | int len; |
c7078de1 IM |
3391 | |
3392 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 3393 | |
1a40243b TH |
3394 | len = snprintf(mask_str, count, "%*pb\n", |
3395 | cpumask_pr_args(tr->tracing_cpumask)); | |
3396 | if (len >= count) { | |
36dfe925 IM |
3397 | count = -EINVAL; |
3398 | goto out_err; | |
3399 | } | |
36dfe925 IM |
3400 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); |
3401 | ||
3402 | out_err: | |
c7078de1 IM |
3403 | mutex_unlock(&tracing_cpumask_update_lock); |
3404 | ||
3405 | return count; | |
3406 | } | |
3407 | ||
3408 | static ssize_t | |
3409 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
3410 | size_t count, loff_t *ppos) | |
3411 | { | |
ccfe9e42 | 3412 | struct trace_array *tr = file_inode(filp)->i_private; |
9e01c1b7 | 3413 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 3414 | int err, cpu; |
9e01c1b7 RR |
3415 | |
3416 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
3417 | return -ENOMEM; | |
c7078de1 | 3418 | |
9e01c1b7 | 3419 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 3420 | if (err) |
36dfe925 IM |
3421 | goto err_unlock; |
3422 | ||
215368e8 LZ |
3423 | mutex_lock(&tracing_cpumask_update_lock); |
3424 | ||
a5e25883 | 3425 | local_irq_disable(); |
0b9b12c1 | 3426 | arch_spin_lock(&tr->max_lock); |
ab46428c | 3427 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
3428 | /* |
3429 | * Increase/decrease the disabled counter if we are | |
3430 | * about to flip a bit in the cpumask: | |
3431 | */ | |
ccfe9e42 | 3432 | if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3433 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3434 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3435 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 3436 | } |
ccfe9e42 | 3437 | if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3438 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3439 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3440 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
3441 | } |
3442 | } | |
0b9b12c1 | 3443 | arch_spin_unlock(&tr->max_lock); |
a5e25883 | 3444 | local_irq_enable(); |
36dfe925 | 3445 | |
ccfe9e42 | 3446 | cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
3447 | |
3448 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 3449 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
3450 | |
3451 | return count; | |
36dfe925 IM |
3452 | |
3453 | err_unlock: | |
215368e8 | 3454 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
3455 | |
3456 | return err; | |
c7078de1 IM |
3457 | } |
3458 | ||
5e2336a0 | 3459 | static const struct file_operations tracing_cpumask_fops = { |
ccfe9e42 | 3460 | .open = tracing_open_generic_tr, |
c7078de1 IM |
3461 | .read = tracing_cpumask_read, |
3462 | .write = tracing_cpumask_write, | |
ccfe9e42 | 3463 | .release = tracing_release_generic_tr, |
b444786f | 3464 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3465 | }; |
3466 | ||
fdb372ed | 3467 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 3468 | { |
d8e83d26 | 3469 | struct tracer_opt *trace_opts; |
2b6080f2 | 3470 | struct trace_array *tr = m->private; |
d8e83d26 | 3471 | u32 tracer_flags; |
d8e83d26 | 3472 | int i; |
adf9f195 | 3473 | |
d8e83d26 | 3474 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3475 | tracer_flags = tr->current_trace->flags->val; |
3476 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 3477 | |
bc0c38d1 SR |
3478 | for (i = 0; trace_options[i]; i++) { |
3479 | if (trace_flags & (1 << i)) | |
fdb372ed | 3480 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 3481 | else |
fdb372ed | 3482 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
3483 | } |
3484 | ||
adf9f195 FW |
3485 | for (i = 0; trace_opts[i].name; i++) { |
3486 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 3487 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 3488 | else |
fdb372ed | 3489 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 3490 | } |
d8e83d26 | 3491 | mutex_unlock(&trace_types_lock); |
adf9f195 | 3492 | |
fdb372ed | 3493 | return 0; |
bc0c38d1 | 3494 | } |
bc0c38d1 | 3495 | |
8c1a49ae | 3496 | static int __set_tracer_option(struct trace_array *tr, |
8d18eaaf LZ |
3497 | struct tracer_flags *tracer_flags, |
3498 | struct tracer_opt *opts, int neg) | |
3499 | { | |
8c1a49ae | 3500 | struct tracer *trace = tr->current_trace; |
8d18eaaf | 3501 | int ret; |
bc0c38d1 | 3502 | |
8c1a49ae | 3503 | ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); |
8d18eaaf LZ |
3504 | if (ret) |
3505 | return ret; | |
3506 | ||
3507 | if (neg) | |
3508 | tracer_flags->val &= ~opts->bit; | |
3509 | else | |
3510 | tracer_flags->val |= opts->bit; | |
3511 | return 0; | |
bc0c38d1 SR |
3512 | } |
3513 | ||
adf9f195 | 3514 | /* Try to assign a tracer specific option */ |
8c1a49ae | 3515 | static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) |
adf9f195 | 3516 | { |
8c1a49ae | 3517 | struct tracer *trace = tr->current_trace; |
7770841e | 3518 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 3519 | struct tracer_opt *opts = NULL; |
8d18eaaf | 3520 | int i; |
adf9f195 | 3521 | |
7770841e Z |
3522 | for (i = 0; tracer_flags->opts[i].name; i++) { |
3523 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 3524 | |
8d18eaaf | 3525 | if (strcmp(cmp, opts->name) == 0) |
8c1a49ae | 3526 | return __set_tracer_option(tr, trace->flags, opts, neg); |
adf9f195 | 3527 | } |
adf9f195 | 3528 | |
8d18eaaf | 3529 | return -EINVAL; |
adf9f195 FW |
3530 | } |
3531 | ||
613f04a0 SRRH |
3532 | /* Some tracers require overwrite to stay enabled */ |
3533 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
3534 | { | |
3535 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
3536 | return -1; | |
3537 | ||
3538 | return 0; | |
3539 | } | |
3540 | ||
2b6080f2 | 3541 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
3542 | { |
3543 | /* do nothing if flag is already set */ | |
3544 | if (!!(trace_flags & mask) == !!enabled) | |
613f04a0 SRRH |
3545 | return 0; |
3546 | ||
3547 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 | 3548 | if (tr->current_trace->flag_changed) |
bf6065b5 | 3549 | if (tr->current_trace->flag_changed(tr, mask, !!enabled)) |
613f04a0 | 3550 | return -EINVAL; |
af4617bd SR |
3551 | |
3552 | if (enabled) | |
3553 | trace_flags |= mask; | |
3554 | else | |
3555 | trace_flags &= ~mask; | |
e870e9a1 LZ |
3556 | |
3557 | if (mask == TRACE_ITER_RECORD_CMD) | |
3558 | trace_event_enable_cmd_record(enabled); | |
750912fa | 3559 | |
80902822 | 3560 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 3561 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 3562 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 3563 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
3564 | #endif |
3565 | } | |
81698831 SR |
3566 | |
3567 | if (mask == TRACE_ITER_PRINTK) | |
3568 | trace_printk_start_stop_comm(enabled); | |
613f04a0 SRRH |
3569 | |
3570 | return 0; | |
af4617bd SR |
3571 | } |
3572 | ||
2b6080f2 | 3573 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 3574 | { |
8d18eaaf | 3575 | char *cmp; |
bc0c38d1 | 3576 | int neg = 0; |
613f04a0 | 3577 | int ret = -ENODEV; |
bc0c38d1 SR |
3578 | int i; |
3579 | ||
7bcfaf54 | 3580 | cmp = strstrip(option); |
bc0c38d1 | 3581 | |
8d18eaaf | 3582 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3583 | neg = 1; |
3584 | cmp += 2; | |
3585 | } | |
3586 | ||
69d34da2 SRRH |
3587 | mutex_lock(&trace_types_lock); |
3588 | ||
bc0c38d1 | 3589 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3590 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3591 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3592 | break; |
3593 | } | |
3594 | } | |
adf9f195 FW |
3595 | |
3596 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3597 | if (!trace_options[i]) |
8c1a49ae | 3598 | ret = set_tracer_option(tr, cmp, neg); |
69d34da2 SRRH |
3599 | |
3600 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3601 | |
7bcfaf54 SR |
3602 | return ret; |
3603 | } | |
3604 | ||
3605 | static ssize_t | |
3606 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3607 | size_t cnt, loff_t *ppos) | |
3608 | { | |
2b6080f2 SR |
3609 | struct seq_file *m = filp->private_data; |
3610 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3611 | char buf[64]; |
613f04a0 | 3612 | int ret; |
7bcfaf54 SR |
3613 | |
3614 | if (cnt >= sizeof(buf)) | |
3615 | return -EINVAL; | |
3616 | ||
3617 | if (copy_from_user(&buf, ubuf, cnt)) | |
3618 | return -EFAULT; | |
3619 | ||
a8dd2176 SR |
3620 | buf[cnt] = 0; |
3621 | ||
2b6080f2 | 3622 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
3623 | if (ret < 0) |
3624 | return ret; | |
7bcfaf54 | 3625 | |
cf8517cf | 3626 | *ppos += cnt; |
bc0c38d1 SR |
3627 | |
3628 | return cnt; | |
3629 | } | |
3630 | ||
fdb372ed LZ |
3631 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
3632 | { | |
7b85af63 | 3633 | struct trace_array *tr = inode->i_private; |
f77d09a3 | 3634 | int ret; |
7b85af63 | 3635 | |
fdb372ed LZ |
3636 | if (tracing_disabled) |
3637 | return -ENODEV; | |
2b6080f2 | 3638 | |
7b85af63 SRRH |
3639 | if (trace_array_get(tr) < 0) |
3640 | return -ENODEV; | |
3641 | ||
f77d09a3 AL |
3642 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
3643 | if (ret < 0) | |
3644 | trace_array_put(tr); | |
3645 | ||
3646 | return ret; | |
fdb372ed LZ |
3647 | } |
3648 | ||
5e2336a0 | 3649 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
3650 | .open = tracing_trace_options_open, |
3651 | .read = seq_read, | |
3652 | .llseek = seq_lseek, | |
7b85af63 | 3653 | .release = tracing_single_release_tr, |
ee6bce52 | 3654 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
3655 | }; |
3656 | ||
7bd2f24c IM |
3657 | static const char readme_msg[] = |
3658 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
3659 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
3660 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
3661 | " Important files:\n" | |
3662 | " trace\t\t\t- The static contents of the buffer\n" | |
3663 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
3664 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
3665 | " current_tracer\t- function and latency tracers\n" | |
3666 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
3667 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" | |
3668 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
3669 | " trace_clock\t\t-change the clock used to order events\n" | |
3670 | " local: Per cpu clock but may not be synced across CPUs\n" | |
3671 | " global: Synced across CPUs but slows tracing down.\n" | |
3672 | " counter: Not a clock, but just an increment\n" | |
3673 | " uptime: Jiffy counter from time of boot\n" | |
3674 | " perf: Same clock that perf events use\n" | |
3675 | #ifdef CONFIG_X86_64 | |
3676 | " x86-tsc: TSC cycle counter\n" | |
3677 | #endif | |
3678 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" | |
3679 | " tracing_cpumask\t- Limit which CPUs to trace\n" | |
3680 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
3681 | "\t\t\t Remove sub-buffer with rmdir\n" | |
3682 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
71485c45 SRRH |
3683 | "\t\t\t Disable an option by adding a suffix 'no' to the\n" |
3684 | "\t\t\t option name\n" | |
939c7a4f | 3685 | " saved_cmdlines_size\t- echo command number in here to store comm-pid list\n" |
22f45649 SRRH |
3686 | #ifdef CONFIG_DYNAMIC_FTRACE |
3687 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
71485c45 SRRH |
3688 | " set_ftrace_filter\t- echo function name in here to only trace these\n" |
3689 | "\t\t\t functions\n" | |
3690 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
3691 | "\t modules: Can select a group via module\n" | |
3692 | "\t Format: :mod:<module-name>\n" | |
3693 | "\t example: echo :mod:ext3 > set_ftrace_filter\n" | |
3694 | "\t triggers: a command to perform when function is hit\n" | |
3695 | "\t Format: <function>:<trigger>[:count]\n" | |
3696 | "\t trigger: traceon, traceoff\n" | |
3697 | "\t\t enable_event:<system>:<event>\n" | |
3698 | "\t\t disable_event:<system>:<event>\n" | |
22f45649 | 3699 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3700 | "\t\t stacktrace\n" |
22f45649 SRRH |
3701 | #endif |
3702 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3703 | "\t\t snapshot\n" |
22f45649 | 3704 | #endif |
17a280ea SRRH |
3705 | "\t\t dump\n" |
3706 | "\t\t cpudump\n" | |
71485c45 SRRH |
3707 | "\t example: echo do_fault:traceoff > set_ftrace_filter\n" |
3708 | "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
3709 | "\t The first one will disable tracing every time do_fault is hit\n" | |
3710 | "\t The second will disable tracing at most 3 times when do_trap is hit\n" | |
3711 | "\t The first time do trap is hit and it disables tracing, the\n" | |
3712 | "\t counter will decrement to 2. If tracing is already disabled,\n" | |
3713 | "\t the counter will not decrement. It only decrements when the\n" | |
3714 | "\t trigger did work\n" | |
3715 | "\t To remove trigger without count:\n" | |
3716 | "\t echo '!<function>:<trigger> > set_ftrace_filter\n" | |
3717 | "\t To remove trigger with a count:\n" | |
3718 | "\t echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
22f45649 | 3719 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" |
71485c45 SRRH |
3720 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" |
3721 | "\t modules: Can select a group via module command :mod:\n" | |
3722 | "\t Does not accept triggers\n" | |
22f45649 SRRH |
3723 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
3724 | #ifdef CONFIG_FUNCTION_TRACER | |
71485c45 SRRH |
3725 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" |
3726 | "\t\t (function)\n" | |
22f45649 SRRH |
3727 | #endif |
3728 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
3729 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
d048a8c7 | 3730 | " set_graph_notrace\t- Do not trace the nested calls of a function (function_graph)\n" |
22f45649 SRRH |
3731 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" |
3732 | #endif | |
3733 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 SRRH |
3734 | "\n snapshot\t\t- Like 'trace' but shows the content of the static\n" |
3735 | "\t\t\t snapshot buffer. Read the contents for more\n" | |
3736 | "\t\t\t information\n" | |
22f45649 | 3737 | #endif |
991821c8 | 3738 | #ifdef CONFIG_STACK_TRACER |
22f45649 SRRH |
3739 | " stack_trace\t\t- Shows the max stack trace when active\n" |
3740 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
71485c45 SRRH |
3741 | "\t\t\t Write into this file to reset the max size (trigger a\n" |
3742 | "\t\t\t new trace)\n" | |
22f45649 | 3743 | #ifdef CONFIG_DYNAMIC_FTRACE |
71485c45 SRRH |
3744 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n" |
3745 | "\t\t\t traces\n" | |
22f45649 | 3746 | #endif |
991821c8 | 3747 | #endif /* CONFIG_STACK_TRACER */ |
26f25564 TZ |
3748 | " events/\t\t- Directory containing all trace event subsystems:\n" |
3749 | " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" | |
3750 | " events/<system>/\t- Directory containing all trace events for <system>:\n" | |
71485c45 SRRH |
3751 | " enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n" |
3752 | "\t\t\t events\n" | |
26f25564 | 3753 | " filter\t\t- If set, only events passing filter are traced\n" |
71485c45 SRRH |
3754 | " events/<system>/<event>/\t- Directory containing control files for\n" |
3755 | "\t\t\t <event>:\n" | |
26f25564 TZ |
3756 | " enable\t\t- Write 0/1 to enable/disable tracing of <event>\n" |
3757 | " filter\t\t- If set, only events passing filter are traced\n" | |
3758 | " trigger\t\t- If set, a command to perform when event is hit\n" | |
71485c45 SRRH |
3759 | "\t Format: <trigger>[:count][if <filter>]\n" |
3760 | "\t trigger: traceon, traceoff\n" | |
3761 | "\t enable_event:<system>:<event>\n" | |
3762 | "\t disable_event:<system>:<event>\n" | |
26f25564 | 3763 | #ifdef CONFIG_STACKTRACE |
71485c45 | 3764 | "\t\t stacktrace\n" |
26f25564 TZ |
3765 | #endif |
3766 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 3767 | "\t\t snapshot\n" |
26f25564 | 3768 | #endif |
71485c45 SRRH |
3769 | "\t example: echo traceoff > events/block/block_unplug/trigger\n" |
3770 | "\t echo traceoff:3 > events/block/block_unplug/trigger\n" | |
3771 | "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" | |
3772 | "\t events/block/block_unplug/trigger\n" | |
3773 | "\t The first disables tracing every time block_unplug is hit.\n" | |
3774 | "\t The second disables tracing the first 3 times block_unplug is hit.\n" | |
3775 | "\t The third enables the kmalloc event the first 3 times block_unplug\n" | |
3776 | "\t is hit and has value of greater than 1 for the 'nr_rq' event field.\n" | |
3777 | "\t Like function triggers, the counter is only decremented if it\n" | |
3778 | "\t enabled or disabled tracing.\n" | |
3779 | "\t To remove a trigger without a count:\n" | |
3780 | "\t echo '!<trigger> > <system>/<event>/trigger\n" | |
3781 | "\t To remove a trigger with a count:\n" | |
3782 | "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" | |
3783 | "\t Filters can be ignored when removing a trigger.\n" | |
7bd2f24c IM |
3784 | ; |
3785 | ||
3786 | static ssize_t | |
3787 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
3788 | size_t cnt, loff_t *ppos) | |
3789 | { | |
3790 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
3791 | readme_msg, strlen(readme_msg)); | |
3792 | } | |
3793 | ||
5e2336a0 | 3794 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
3795 | .open = tracing_open_generic, |
3796 | .read = tracing_readme_read, | |
b444786f | 3797 | .llseek = generic_file_llseek, |
7bd2f24c IM |
3798 | }; |
3799 | ||
42584c81 YY |
3800 | static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos) |
3801 | { | |
3802 | unsigned int *ptr = v; | |
69abe6a5 | 3803 | |
42584c81 YY |
3804 | if (*pos || m->count) |
3805 | ptr++; | |
69abe6a5 | 3806 | |
42584c81 | 3807 | (*pos)++; |
69abe6a5 | 3808 | |
939c7a4f YY |
3809 | for (; ptr < &savedcmd->map_cmdline_to_pid[savedcmd->cmdline_num]; |
3810 | ptr++) { | |
42584c81 YY |
3811 | if (*ptr == -1 || *ptr == NO_CMDLINE_MAP) |
3812 | continue; | |
69abe6a5 | 3813 | |
42584c81 YY |
3814 | return ptr; |
3815 | } | |
69abe6a5 | 3816 | |
42584c81 YY |
3817 | return NULL; |
3818 | } | |
3819 | ||
3820 | static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos) | |
3821 | { | |
3822 | void *v; | |
3823 | loff_t l = 0; | |
69abe6a5 | 3824 | |
4c27e756 SRRH |
3825 | preempt_disable(); |
3826 | arch_spin_lock(&trace_cmdline_lock); | |
3827 | ||
939c7a4f | 3828 | v = &savedcmd->map_cmdline_to_pid[0]; |
42584c81 YY |
3829 | while (l <= *pos) { |
3830 | v = saved_cmdlines_next(m, v, &l); | |
3831 | if (!v) | |
3832 | return NULL; | |
69abe6a5 AP |
3833 | } |
3834 | ||
42584c81 YY |
3835 | return v; |
3836 | } | |
3837 | ||
3838 | static void saved_cmdlines_stop(struct seq_file *m, void *v) | |
3839 | { | |
4c27e756 SRRH |
3840 | arch_spin_unlock(&trace_cmdline_lock); |
3841 | preempt_enable(); | |
42584c81 | 3842 | } |
69abe6a5 | 3843 | |
42584c81 YY |
3844 | static int saved_cmdlines_show(struct seq_file *m, void *v) |
3845 | { | |
3846 | char buf[TASK_COMM_LEN]; | |
3847 | unsigned int *pid = v; | |
69abe6a5 | 3848 | |
4c27e756 | 3849 | __trace_find_cmdline(*pid, buf); |
42584c81 YY |
3850 | seq_printf(m, "%d %s\n", *pid, buf); |
3851 | return 0; | |
3852 | } | |
3853 | ||
3854 | static const struct seq_operations tracing_saved_cmdlines_seq_ops = { | |
3855 | .start = saved_cmdlines_start, | |
3856 | .next = saved_cmdlines_next, | |
3857 | .stop = saved_cmdlines_stop, | |
3858 | .show = saved_cmdlines_show, | |
3859 | }; | |
3860 | ||
3861 | static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp) | |
3862 | { | |
3863 | if (tracing_disabled) | |
3864 | return -ENODEV; | |
3865 | ||
3866 | return seq_open(filp, &tracing_saved_cmdlines_seq_ops); | |
69abe6a5 AP |
3867 | } |
3868 | ||
3869 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
42584c81 YY |
3870 | .open = tracing_saved_cmdlines_open, |
3871 | .read = seq_read, | |
3872 | .llseek = seq_lseek, | |
3873 | .release = seq_release, | |
69abe6a5 AP |
3874 | }; |
3875 | ||
939c7a4f YY |
3876 | static ssize_t |
3877 | tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf, | |
3878 | size_t cnt, loff_t *ppos) | |
3879 | { | |
3880 | char buf[64]; | |
3881 | int r; | |
3882 | ||
3883 | arch_spin_lock(&trace_cmdline_lock); | |
a6af8fbf | 3884 | r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num); |
939c7a4f YY |
3885 | arch_spin_unlock(&trace_cmdline_lock); |
3886 | ||
3887 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3888 | } | |
3889 | ||
3890 | static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s) | |
3891 | { | |
3892 | kfree(s->saved_cmdlines); | |
3893 | kfree(s->map_cmdline_to_pid); | |
3894 | kfree(s); | |
3895 | } | |
3896 | ||
3897 | static int tracing_resize_saved_cmdlines(unsigned int val) | |
3898 | { | |
3899 | struct saved_cmdlines_buffer *s, *savedcmd_temp; | |
3900 | ||
a6af8fbf | 3901 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
939c7a4f YY |
3902 | if (!s) |
3903 | return -ENOMEM; | |
3904 | ||
3905 | if (allocate_cmdlines_buffer(val, s) < 0) { | |
3906 | kfree(s); | |
3907 | return -ENOMEM; | |
3908 | } | |
3909 | ||
3910 | arch_spin_lock(&trace_cmdline_lock); | |
3911 | savedcmd_temp = savedcmd; | |
3912 | savedcmd = s; | |
3913 | arch_spin_unlock(&trace_cmdline_lock); | |
3914 | free_saved_cmdlines_buffer(savedcmd_temp); | |
3915 | ||
3916 | return 0; | |
3917 | } | |
3918 | ||
3919 | static ssize_t | |
3920 | tracing_saved_cmdlines_size_write(struct file *filp, const char __user *ubuf, | |
3921 | size_t cnt, loff_t *ppos) | |
3922 | { | |
3923 | unsigned long val; | |
3924 | int ret; | |
3925 | ||
3926 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
3927 | if (ret) | |
3928 | return ret; | |
3929 | ||
3930 | /* must have at least 1 entry or less than PID_MAX_DEFAULT */ | |
3931 | if (!val || val > PID_MAX_DEFAULT) | |
3932 | return -EINVAL; | |
3933 | ||
3934 | ret = tracing_resize_saved_cmdlines((unsigned int)val); | |
3935 | if (ret < 0) | |
3936 | return ret; | |
3937 | ||
3938 | *ppos += cnt; | |
3939 | ||
3940 | return cnt; | |
3941 | } | |
3942 | ||
3943 | static const struct file_operations tracing_saved_cmdlines_size_fops = { | |
3944 | .open = tracing_open_generic, | |
3945 | .read = tracing_saved_cmdlines_size_read, | |
3946 | .write = tracing_saved_cmdlines_size_write, | |
3947 | }; | |
3948 | ||
9828413d SRRH |
3949 | #ifdef CONFIG_TRACE_ENUM_MAP_FILE |
3950 | static union trace_enum_map_item * | |
3951 | update_enum_map(union trace_enum_map_item *ptr) | |
3952 | { | |
3953 | if (!ptr->map.enum_string) { | |
3954 | if (ptr->tail.next) { | |
3955 | ptr = ptr->tail.next; | |
3956 | /* Set ptr to the next real item (skip head) */ | |
3957 | ptr++; | |
3958 | } else | |
3959 | return NULL; | |
3960 | } | |
3961 | return ptr; | |
3962 | } | |
3963 | ||
3964 | static void *enum_map_next(struct seq_file *m, void *v, loff_t *pos) | |
3965 | { | |
3966 | union trace_enum_map_item *ptr = v; | |
3967 | ||
3968 | /* | |
3969 | * Paranoid! If ptr points to end, we don't want to increment past it. | |
3970 | * This really should never happen. | |
3971 | */ | |
3972 | ptr = update_enum_map(ptr); | |
3973 | if (WARN_ON_ONCE(!ptr)) | |
3974 | return NULL; | |
3975 | ||
3976 | ptr++; | |
3977 | ||
3978 | (*pos)++; | |
3979 | ||
3980 | ptr = update_enum_map(ptr); | |
3981 | ||
3982 | return ptr; | |
3983 | } | |
3984 | ||
3985 | static void *enum_map_start(struct seq_file *m, loff_t *pos) | |
3986 | { | |
3987 | union trace_enum_map_item *v; | |
3988 | loff_t l = 0; | |
3989 | ||
3990 | mutex_lock(&trace_enum_mutex); | |
3991 | ||
3992 | v = trace_enum_maps; | |
3993 | if (v) | |
3994 | v++; | |
3995 | ||
3996 | while (v && l < *pos) { | |
3997 | v = enum_map_next(m, v, &l); | |
3998 | } | |
3999 | ||
4000 | return v; | |
4001 | } | |
4002 | ||
4003 | static void enum_map_stop(struct seq_file *m, void *v) | |
4004 | { | |
4005 | mutex_unlock(&trace_enum_mutex); | |
4006 | } | |
4007 | ||
4008 | static int enum_map_show(struct seq_file *m, void *v) | |
4009 | { | |
4010 | union trace_enum_map_item *ptr = v; | |
4011 | ||
4012 | seq_printf(m, "%s %ld (%s)\n", | |
4013 | ptr->map.enum_string, ptr->map.enum_value, | |
4014 | ptr->map.system); | |
4015 | ||
4016 | return 0; | |
4017 | } | |
4018 | ||
4019 | static const struct seq_operations tracing_enum_map_seq_ops = { | |
4020 | .start = enum_map_start, | |
4021 | .next = enum_map_next, | |
4022 | .stop = enum_map_stop, | |
4023 | .show = enum_map_show, | |
4024 | }; | |
4025 | ||
4026 | static int tracing_enum_map_open(struct inode *inode, struct file *filp) | |
4027 | { | |
4028 | if (tracing_disabled) | |
4029 | return -ENODEV; | |
4030 | ||
4031 | return seq_open(filp, &tracing_enum_map_seq_ops); | |
4032 | } | |
4033 | ||
4034 | static const struct file_operations tracing_enum_map_fops = { | |
4035 | .open = tracing_enum_map_open, | |
4036 | .read = seq_read, | |
4037 | .llseek = seq_lseek, | |
4038 | .release = seq_release, | |
4039 | }; | |
4040 | ||
4041 | static inline union trace_enum_map_item * | |
4042 | trace_enum_jmp_to_tail(union trace_enum_map_item *ptr) | |
4043 | { | |
4044 | /* Return tail of array given the head */ | |
4045 | return ptr + ptr->head.length + 1; | |
4046 | } | |
4047 | ||
4048 | static void | |
4049 | trace_insert_enum_map_file(struct module *mod, struct trace_enum_map **start, | |
4050 | int len) | |
4051 | { | |
4052 | struct trace_enum_map **stop; | |
4053 | struct trace_enum_map **map; | |
4054 | union trace_enum_map_item *map_array; | |
4055 | union trace_enum_map_item *ptr; | |
4056 | ||
4057 | stop = start + len; | |
4058 | ||
4059 | /* | |
4060 | * The trace_enum_maps contains the map plus a head and tail item, | |
4061 | * where the head holds the module and length of array, and the | |
4062 | * tail holds a pointer to the next list. | |
4063 | */ | |
4064 | map_array = kmalloc(sizeof(*map_array) * (len + 2), GFP_KERNEL); | |
4065 | if (!map_array) { | |
4066 | pr_warning("Unable to allocate trace enum mapping\n"); | |
4067 | return; | |
4068 | } | |
4069 | ||
4070 | mutex_lock(&trace_enum_mutex); | |
4071 | ||
4072 | if (!trace_enum_maps) | |
4073 | trace_enum_maps = map_array; | |
4074 | else { | |
4075 | ptr = trace_enum_maps; | |
4076 | for (;;) { | |
4077 | ptr = trace_enum_jmp_to_tail(ptr); | |
4078 | if (!ptr->tail.next) | |
4079 | break; | |
4080 | ptr = ptr->tail.next; | |
4081 | ||
4082 | } | |
4083 | ptr->tail.next = map_array; | |
4084 | } | |
4085 | map_array->head.mod = mod; | |
4086 | map_array->head.length = len; | |
4087 | map_array++; | |
4088 | ||
4089 | for (map = start; (unsigned long)map < (unsigned long)stop; map++) { | |
4090 | map_array->map = **map; | |
4091 | map_array++; | |
4092 | } | |
4093 | memset(map_array, 0, sizeof(*map_array)); | |
4094 | ||
4095 | mutex_unlock(&trace_enum_mutex); | |
4096 | } | |
4097 | ||
4098 | static void trace_create_enum_file(struct dentry *d_tracer) | |
4099 | { | |
4100 | trace_create_file("enum_map", 0444, d_tracer, | |
4101 | NULL, &tracing_enum_map_fops); | |
4102 | } | |
4103 | ||
4104 | #else /* CONFIG_TRACE_ENUM_MAP_FILE */ | |
4105 | static inline void trace_create_enum_file(struct dentry *d_tracer) { } | |
4106 | static inline void trace_insert_enum_map_file(struct module *mod, | |
4107 | struct trace_enum_map **start, int len) { } | |
4108 | #endif /* !CONFIG_TRACE_ENUM_MAP_FILE */ | |
4109 | ||
4110 | static void trace_insert_enum_map(struct module *mod, | |
4111 | struct trace_enum_map **start, int len) | |
0c564a53 SRRH |
4112 | { |
4113 | struct trace_enum_map **map; | |
0c564a53 SRRH |
4114 | |
4115 | if (len <= 0) | |
4116 | return; | |
4117 | ||
4118 | map = start; | |
4119 | ||
4120 | trace_event_enum_update(map, len); | |
9828413d SRRH |
4121 | |
4122 | trace_insert_enum_map_file(mod, start, len); | |
0c564a53 SRRH |
4123 | } |
4124 | ||
bc0c38d1 SR |
4125 | static ssize_t |
4126 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
4127 | size_t cnt, loff_t *ppos) | |
4128 | { | |
2b6080f2 | 4129 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 4130 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
4131 | int r; |
4132 | ||
4133 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 4134 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
4135 | mutex_unlock(&trace_types_lock); |
4136 | ||
4bf39a94 | 4137 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
4138 | } |
4139 | ||
b6f11df2 ACM |
4140 | int tracer_init(struct tracer *t, struct trace_array *tr) |
4141 | { | |
12883efb | 4142 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
4143 | return t->init(tr); |
4144 | } | |
4145 | ||
12883efb | 4146 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
4147 | { |
4148 | int cpu; | |
737223fb | 4149 | |
438ced17 | 4150 | for_each_tracing_cpu(cpu) |
12883efb | 4151 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
4152 | } |
4153 | ||
12883efb | 4154 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 4155 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
4156 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
4157 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
4158 | { |
4159 | int cpu, ret = 0; | |
4160 | ||
4161 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
4162 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
4163 | ret = ring_buffer_resize(trace_buf->buffer, |
4164 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
4165 | if (ret < 0) |
4166 | break; | |
12883efb SRRH |
4167 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
4168 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
4169 | } |
4170 | } else { | |
12883efb SRRH |
4171 | ret = ring_buffer_resize(trace_buf->buffer, |
4172 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 4173 | if (ret == 0) |
12883efb SRRH |
4174 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
4175 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
4176 | } |
4177 | ||
4178 | return ret; | |
4179 | } | |
12883efb | 4180 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 4181 | |
2b6080f2 SR |
4182 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
4183 | unsigned long size, int cpu) | |
73c5162a SR |
4184 | { |
4185 | int ret; | |
4186 | ||
4187 | /* | |
4188 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
4189 | * we use the size that was given, and we can forget about |
4190 | * expanding it later. | |
73c5162a | 4191 | */ |
55034cd6 | 4192 | ring_buffer_expanded = true; |
73c5162a | 4193 | |
b382ede6 | 4194 | /* May be called before buffers are initialized */ |
12883efb | 4195 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
4196 | return 0; |
4197 | ||
12883efb | 4198 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
4199 | if (ret < 0) |
4200 | return ret; | |
4201 | ||
12883efb | 4202 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
4203 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
4204 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
4205 | goto out; |
4206 | ||
12883efb | 4207 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 4208 | if (ret < 0) { |
12883efb SRRH |
4209 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
4210 | &tr->trace_buffer, cpu); | |
73c5162a | 4211 | if (r < 0) { |
a123c52b SR |
4212 | /* |
4213 | * AARGH! We are left with different | |
4214 | * size max buffer!!!! | |
4215 | * The max buffer is our "snapshot" buffer. | |
4216 | * When a tracer needs a snapshot (one of the | |
4217 | * latency tracers), it swaps the max buffer | |
4218 | * with the saved snap shot. We succeeded to | |
4219 | * update the size of the main buffer, but failed to | |
4220 | * update the size of the max buffer. But when we tried | |
4221 | * to reset the main buffer to the original size, we | |
4222 | * failed there too. This is very unlikely to | |
4223 | * happen, but if it does, warn and kill all | |
4224 | * tracing. | |
4225 | */ | |
73c5162a SR |
4226 | WARN_ON(1); |
4227 | tracing_disabled = 1; | |
4228 | } | |
4229 | return ret; | |
4230 | } | |
4231 | ||
438ced17 | 4232 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 4233 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 4234 | else |
12883efb | 4235 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 4236 | |
ef710e10 | 4237 | out: |
12883efb SRRH |
4238 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
4239 | ||
438ced17 | 4240 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 4241 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 4242 | else |
12883efb | 4243 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
4244 | |
4245 | return ret; | |
4246 | } | |
4247 | ||
2b6080f2 SR |
4248 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
4249 | unsigned long size, int cpu_id) | |
4f271a2a | 4250 | { |
83f40318 | 4251 | int ret = size; |
4f271a2a VN |
4252 | |
4253 | mutex_lock(&trace_types_lock); | |
4254 | ||
438ced17 VN |
4255 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
4256 | /* make sure, this cpu is enabled in the mask */ | |
4257 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
4258 | ret = -EINVAL; | |
4259 | goto out; | |
4260 | } | |
4261 | } | |
4f271a2a | 4262 | |
2b6080f2 | 4263 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
4264 | if (ret < 0) |
4265 | ret = -ENOMEM; | |
4266 | ||
438ced17 | 4267 | out: |
4f271a2a VN |
4268 | mutex_unlock(&trace_types_lock); |
4269 | ||
4270 | return ret; | |
4271 | } | |
4272 | ||
ef710e10 | 4273 | |
1852fcce SR |
4274 | /** |
4275 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
4276 | * | |
4277 | * To save on memory when the tracing is never used on a system with it | |
4278 | * configured in. The ring buffers are set to a minimum size. But once | |
4279 | * a user starts to use the tracing facility, then they need to grow | |
4280 | * to their default size. | |
4281 | * | |
4282 | * This function is to be called when a tracer is about to be used. | |
4283 | */ | |
4284 | int tracing_update_buffers(void) | |
4285 | { | |
4286 | int ret = 0; | |
4287 | ||
1027fcb2 | 4288 | mutex_lock(&trace_types_lock); |
1852fcce | 4289 | if (!ring_buffer_expanded) |
2b6080f2 | 4290 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 4291 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 4292 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
4293 | |
4294 | return ret; | |
4295 | } | |
4296 | ||
577b785f SR |
4297 | struct trace_option_dentry; |
4298 | ||
4299 | static struct trace_option_dentry * | |
2b6080f2 | 4300 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f SR |
4301 | |
4302 | static void | |
4303 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
4304 | ||
6b450d25 SRRH |
4305 | /* |
4306 | * Used to clear out the tracer before deletion of an instance. | |
4307 | * Must have trace_types_lock held. | |
4308 | */ | |
4309 | static void tracing_set_nop(struct trace_array *tr) | |
4310 | { | |
4311 | if (tr->current_trace == &nop_trace) | |
4312 | return; | |
4313 | ||
50512ab5 | 4314 | tr->current_trace->enabled--; |
6b450d25 SRRH |
4315 | |
4316 | if (tr->current_trace->reset) | |
4317 | tr->current_trace->reset(tr); | |
4318 | ||
4319 | tr->current_trace = &nop_trace; | |
4320 | } | |
4321 | ||
09d23a1d | 4322 | static void update_tracer_options(struct trace_array *tr, struct tracer *t) |
bc0c38d1 | 4323 | { |
577b785f | 4324 | static struct trace_option_dentry *topts; |
09d23a1d SRRH |
4325 | |
4326 | /* Only enable if the directory has been created already. */ | |
4327 | if (!tr->dir) | |
4328 | return; | |
4329 | ||
4330 | /* Currently, only the top instance has options */ | |
4331 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL)) | |
4332 | return; | |
4333 | ||
4334 | destroy_trace_option_files(topts); | |
4335 | topts = create_trace_option_files(tr, t); | |
4336 | } | |
4337 | ||
4338 | static int tracing_set_tracer(struct trace_array *tr, const char *buf) | |
4339 | { | |
bc0c38d1 | 4340 | struct tracer *t; |
12883efb | 4341 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 4342 | bool had_max_tr; |
12883efb | 4343 | #endif |
d9e54076 | 4344 | int ret = 0; |
bc0c38d1 | 4345 | |
1027fcb2 SR |
4346 | mutex_lock(&trace_types_lock); |
4347 | ||
73c5162a | 4348 | if (!ring_buffer_expanded) { |
2b6080f2 | 4349 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 4350 | RING_BUFFER_ALL_CPUS); |
73c5162a | 4351 | if (ret < 0) |
59f586db | 4352 | goto out; |
73c5162a SR |
4353 | ret = 0; |
4354 | } | |
4355 | ||
bc0c38d1 SR |
4356 | for (t = trace_types; t; t = t->next) { |
4357 | if (strcmp(t->name, buf) == 0) | |
4358 | break; | |
4359 | } | |
c2931e05 FW |
4360 | if (!t) { |
4361 | ret = -EINVAL; | |
4362 | goto out; | |
4363 | } | |
2b6080f2 | 4364 | if (t == tr->current_trace) |
bc0c38d1 SR |
4365 | goto out; |
4366 | ||
607e2ea1 SRRH |
4367 | /* Some tracers are only allowed for the top level buffer */ |
4368 | if (!trace_ok_for_array(t, tr)) { | |
4369 | ret = -EINVAL; | |
4370 | goto out; | |
4371 | } | |
4372 | ||
cf6ab6d9 SRRH |
4373 | /* If trace pipe files are being read, we can't change the tracer */ |
4374 | if (tr->current_trace->ref) { | |
4375 | ret = -EBUSY; | |
4376 | goto out; | |
4377 | } | |
4378 | ||
9f029e83 | 4379 | trace_branch_disable(); |
613f04a0 | 4380 | |
50512ab5 | 4381 | tr->current_trace->enabled--; |
613f04a0 | 4382 | |
2b6080f2 SR |
4383 | if (tr->current_trace->reset) |
4384 | tr->current_trace->reset(tr); | |
34600f0e | 4385 | |
12883efb | 4386 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 4387 | tr->current_trace = &nop_trace; |
34600f0e | 4388 | |
45ad21ca SRRH |
4389 | #ifdef CONFIG_TRACER_MAX_TRACE |
4390 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
4391 | |
4392 | if (had_max_tr && !t->use_max_tr) { | |
4393 | /* | |
4394 | * We need to make sure that the update_max_tr sees that | |
4395 | * current_trace changed to nop_trace to keep it from | |
4396 | * swapping the buffers after we resize it. | |
4397 | * The update_max_tr is called from interrupts disabled | |
4398 | * so a synchronized_sched() is sufficient. | |
4399 | */ | |
4400 | synchronize_sched(); | |
3209cff4 | 4401 | free_snapshot(tr); |
ef710e10 | 4402 | } |
12883efb | 4403 | #endif |
09d23a1d | 4404 | update_tracer_options(tr, t); |
12883efb SRRH |
4405 | |
4406 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 4407 | if (t->use_max_tr && !had_max_tr) { |
3209cff4 | 4408 | ret = alloc_snapshot(tr); |
d60da506 HT |
4409 | if (ret < 0) |
4410 | goto out; | |
ef710e10 | 4411 | } |
12883efb | 4412 | #endif |
577b785f | 4413 | |
1c80025a | 4414 | if (t->init) { |
b6f11df2 | 4415 | ret = tracer_init(t, tr); |
1c80025a FW |
4416 | if (ret) |
4417 | goto out; | |
4418 | } | |
bc0c38d1 | 4419 | |
2b6080f2 | 4420 | tr->current_trace = t; |
50512ab5 | 4421 | tr->current_trace->enabled++; |
9f029e83 | 4422 | trace_branch_enable(tr); |
bc0c38d1 SR |
4423 | out: |
4424 | mutex_unlock(&trace_types_lock); | |
4425 | ||
d9e54076 PZ |
4426 | return ret; |
4427 | } | |
4428 | ||
4429 | static ssize_t | |
4430 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
4431 | size_t cnt, loff_t *ppos) | |
4432 | { | |
607e2ea1 | 4433 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 4434 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
4435 | int i; |
4436 | size_t ret; | |
e6e7a65a FW |
4437 | int err; |
4438 | ||
4439 | ret = cnt; | |
d9e54076 | 4440 | |
ee6c2c1b LZ |
4441 | if (cnt > MAX_TRACER_SIZE) |
4442 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
4443 | |
4444 | if (copy_from_user(&buf, ubuf, cnt)) | |
4445 | return -EFAULT; | |
4446 | ||
4447 | buf[cnt] = 0; | |
4448 | ||
4449 | /* strip ending whitespace. */ | |
4450 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
4451 | buf[i] = 0; | |
4452 | ||
607e2ea1 | 4453 | err = tracing_set_tracer(tr, buf); |
e6e7a65a FW |
4454 | if (err) |
4455 | return err; | |
d9e54076 | 4456 | |
cf8517cf | 4457 | *ppos += ret; |
bc0c38d1 | 4458 | |
c2931e05 | 4459 | return ret; |
bc0c38d1 SR |
4460 | } |
4461 | ||
4462 | static ssize_t | |
6508fa76 SF |
4463 | tracing_nsecs_read(unsigned long *ptr, char __user *ubuf, |
4464 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 4465 | { |
bc0c38d1 SR |
4466 | char buf[64]; |
4467 | int r; | |
4468 | ||
cffae437 | 4469 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 4470 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
4471 | if (r > sizeof(buf)) |
4472 | r = sizeof(buf); | |
4bf39a94 | 4473 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
4474 | } |
4475 | ||
4476 | static ssize_t | |
6508fa76 SF |
4477 | tracing_nsecs_write(unsigned long *ptr, const char __user *ubuf, |
4478 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 4479 | { |
5e39841c | 4480 | unsigned long val; |
c6caeeb1 | 4481 | int ret; |
bc0c38d1 | 4482 | |
22fe9b54 PH |
4483 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4484 | if (ret) | |
c6caeeb1 | 4485 | return ret; |
bc0c38d1 SR |
4486 | |
4487 | *ptr = val * 1000; | |
4488 | ||
4489 | return cnt; | |
4490 | } | |
4491 | ||
6508fa76 SF |
4492 | static ssize_t |
4493 | tracing_thresh_read(struct file *filp, char __user *ubuf, | |
4494 | size_t cnt, loff_t *ppos) | |
4495 | { | |
4496 | return tracing_nsecs_read(&tracing_thresh, ubuf, cnt, ppos); | |
4497 | } | |
4498 | ||
4499 | static ssize_t | |
4500 | tracing_thresh_write(struct file *filp, const char __user *ubuf, | |
4501 | size_t cnt, loff_t *ppos) | |
4502 | { | |
4503 | struct trace_array *tr = filp->private_data; | |
4504 | int ret; | |
4505 | ||
4506 | mutex_lock(&trace_types_lock); | |
4507 | ret = tracing_nsecs_write(&tracing_thresh, ubuf, cnt, ppos); | |
4508 | if (ret < 0) | |
4509 | goto out; | |
4510 | ||
4511 | if (tr->current_trace->update_thresh) { | |
4512 | ret = tr->current_trace->update_thresh(tr); | |
4513 | if (ret < 0) | |
4514 | goto out; | |
4515 | } | |
4516 | ||
4517 | ret = cnt; | |
4518 | out: | |
4519 | mutex_unlock(&trace_types_lock); | |
4520 | ||
4521 | return ret; | |
4522 | } | |
4523 | ||
4524 | static ssize_t | |
4525 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
4526 | size_t cnt, loff_t *ppos) | |
4527 | { | |
4528 | return tracing_nsecs_read(filp->private_data, ubuf, cnt, ppos); | |
4529 | } | |
4530 | ||
4531 | static ssize_t | |
4532 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
4533 | size_t cnt, loff_t *ppos) | |
4534 | { | |
4535 | return tracing_nsecs_write(filp->private_data, ubuf, cnt, ppos); | |
4536 | } | |
4537 | ||
b3806b43 SR |
4538 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
4539 | { | |
15544209 | 4540 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4541 | struct trace_iterator *iter; |
b04cc6b1 | 4542 | int ret = 0; |
b3806b43 SR |
4543 | |
4544 | if (tracing_disabled) | |
4545 | return -ENODEV; | |
4546 | ||
7b85af63 SRRH |
4547 | if (trace_array_get(tr) < 0) |
4548 | return -ENODEV; | |
4549 | ||
b04cc6b1 FW |
4550 | mutex_lock(&trace_types_lock); |
4551 | ||
b3806b43 SR |
4552 | /* create a buffer to store the information to pass to userspace */ |
4553 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
4554 | if (!iter) { |
4555 | ret = -ENOMEM; | |
f77d09a3 | 4556 | __trace_array_put(tr); |
b04cc6b1 FW |
4557 | goto out; |
4558 | } | |
b3806b43 | 4559 | |
3a161d99 | 4560 | trace_seq_init(&iter->seq); |
d716ff71 | 4561 | iter->trace = tr->current_trace; |
d7350c3f | 4562 | |
4462344e | 4563 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 4564 | ret = -ENOMEM; |
d7350c3f | 4565 | goto fail; |
4462344e RR |
4566 | } |
4567 | ||
a309720c | 4568 | /* trace pipe does not show start of buffer */ |
4462344e | 4569 | cpumask_setall(iter->started); |
a309720c | 4570 | |
112f38a7 SR |
4571 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
4572 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
4573 | ||
8be0709f | 4574 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 4575 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
4576 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
4577 | ||
15544209 ON |
4578 | iter->tr = tr; |
4579 | iter->trace_buffer = &tr->trace_buffer; | |
4580 | iter->cpu_file = tracing_get_cpu(inode); | |
d7350c3f | 4581 | mutex_init(&iter->mutex); |
b3806b43 SR |
4582 | filp->private_data = iter; |
4583 | ||
107bad8b SR |
4584 | if (iter->trace->pipe_open) |
4585 | iter->trace->pipe_open(iter); | |
107bad8b | 4586 | |
b444786f | 4587 | nonseekable_open(inode, filp); |
cf6ab6d9 SRRH |
4588 | |
4589 | tr->current_trace->ref++; | |
b04cc6b1 FW |
4590 | out: |
4591 | mutex_unlock(&trace_types_lock); | |
4592 | return ret; | |
d7350c3f FW |
4593 | |
4594 | fail: | |
4595 | kfree(iter->trace); | |
4596 | kfree(iter); | |
7b85af63 | 4597 | __trace_array_put(tr); |
d7350c3f FW |
4598 | mutex_unlock(&trace_types_lock); |
4599 | return ret; | |
b3806b43 SR |
4600 | } |
4601 | ||
4602 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
4603 | { | |
4604 | struct trace_iterator *iter = file->private_data; | |
15544209 | 4605 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4606 | |
b04cc6b1 FW |
4607 | mutex_lock(&trace_types_lock); |
4608 | ||
cf6ab6d9 SRRH |
4609 | tr->current_trace->ref--; |
4610 | ||
29bf4a5e | 4611 | if (iter->trace->pipe_close) |
c521efd1 SR |
4612 | iter->trace->pipe_close(iter); |
4613 | ||
b04cc6b1 FW |
4614 | mutex_unlock(&trace_types_lock); |
4615 | ||
4462344e | 4616 | free_cpumask_var(iter->started); |
d7350c3f | 4617 | mutex_destroy(&iter->mutex); |
b3806b43 | 4618 | kfree(iter); |
b3806b43 | 4619 | |
7b85af63 SRRH |
4620 | trace_array_put(tr); |
4621 | ||
b3806b43 SR |
4622 | return 0; |
4623 | } | |
4624 | ||
2a2cc8f7 | 4625 | static unsigned int |
cc60cdc9 | 4626 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 4627 | { |
15693458 SRRH |
4628 | /* Iterators are static, they should be filled or empty */ |
4629 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
4630 | return POLLIN | POLLRDNORM; | |
2a2cc8f7 | 4631 | |
15693458 | 4632 | if (trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
4633 | /* |
4634 | * Always select as readable when in blocking mode | |
4635 | */ | |
4636 | return POLLIN | POLLRDNORM; | |
15693458 | 4637 | else |
12883efb | 4638 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 4639 | filp, poll_table); |
2a2cc8f7 | 4640 | } |
2a2cc8f7 | 4641 | |
cc60cdc9 SR |
4642 | static unsigned int |
4643 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
4644 | { | |
4645 | struct trace_iterator *iter = filp->private_data; | |
4646 | ||
4647 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
4648 | } |
4649 | ||
d716ff71 | 4650 | /* Must be called with iter->mutex held. */ |
ff98781b | 4651 | static int tracing_wait_pipe(struct file *filp) |
b3806b43 SR |
4652 | { |
4653 | struct trace_iterator *iter = filp->private_data; | |
8b8b3683 | 4654 | int ret; |
b3806b43 | 4655 | |
b3806b43 | 4656 | while (trace_empty(iter)) { |
2dc8f095 | 4657 | |
107bad8b | 4658 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 4659 | return -EAGAIN; |
107bad8b | 4660 | } |
2dc8f095 | 4661 | |
b3806b43 | 4662 | /* |
250bfd3d | 4663 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
4664 | * We still block if tracing is disabled, but we have never |
4665 | * read anything. This allows a user to cat this file, and | |
4666 | * then enable tracing. But after we have read something, | |
4667 | * we give an EOF when tracing is again disabled. | |
4668 | * | |
4669 | * iter->pos will be 0 if we haven't read anything. | |
4670 | */ | |
10246fa3 | 4671 | if (!tracing_is_on() && iter->pos) |
b3806b43 | 4672 | break; |
f4874261 SRRH |
4673 | |
4674 | mutex_unlock(&iter->mutex); | |
4675 | ||
e30f53aa | 4676 | ret = wait_on_pipe(iter, false); |
f4874261 SRRH |
4677 | |
4678 | mutex_lock(&iter->mutex); | |
4679 | ||
8b8b3683 SRRH |
4680 | if (ret) |
4681 | return ret; | |
b3806b43 SR |
4682 | } |
4683 | ||
ff98781b EGM |
4684 | return 1; |
4685 | } | |
4686 | ||
4687 | /* | |
4688 | * Consumer reader. | |
4689 | */ | |
4690 | static ssize_t | |
4691 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
4692 | size_t cnt, loff_t *ppos) | |
4693 | { | |
4694 | struct trace_iterator *iter = filp->private_data; | |
4695 | ssize_t sret; | |
4696 | ||
4697 | /* return any leftover data */ | |
4698 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
4699 | if (sret != -EBUSY) | |
4700 | return sret; | |
4701 | ||
f9520750 | 4702 | trace_seq_init(&iter->seq); |
ff98781b | 4703 | |
d7350c3f FW |
4704 | /* |
4705 | * Avoid more than one consumer on a single file descriptor | |
4706 | * This is just a matter of traces coherency, the ring buffer itself | |
4707 | * is protected. | |
4708 | */ | |
4709 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
4710 | if (iter->trace->read) { |
4711 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
4712 | if (sret) | |
4713 | goto out; | |
4714 | } | |
4715 | ||
4716 | waitagain: | |
4717 | sret = tracing_wait_pipe(filp); | |
4718 | if (sret <= 0) | |
4719 | goto out; | |
4720 | ||
b3806b43 | 4721 | /* stop when tracing is finished */ |
ff98781b EGM |
4722 | if (trace_empty(iter)) { |
4723 | sret = 0; | |
107bad8b | 4724 | goto out; |
ff98781b | 4725 | } |
b3806b43 SR |
4726 | |
4727 | if (cnt >= PAGE_SIZE) | |
4728 | cnt = PAGE_SIZE - 1; | |
4729 | ||
53d0aa77 | 4730 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
4731 | memset(&iter->seq, 0, |
4732 | sizeof(struct trace_iterator) - | |
4733 | offsetof(struct trace_iterator, seq)); | |
ed5467da | 4734 | cpumask_clear(iter->started); |
4823ed7e | 4735 | iter->pos = -1; |
b3806b43 | 4736 | |
4f535968 | 4737 | trace_event_read_lock(); |
7e53bd42 | 4738 | trace_access_lock(iter->cpu_file); |
955b61e5 | 4739 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 4740 | enum print_line_t ret; |
5ac48378 | 4741 | int save_len = iter->seq.seq.len; |
088b1e42 | 4742 | |
f9896bf3 | 4743 | ret = print_trace_line(iter); |
2c4f035f | 4744 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 | 4745 | /* don't print partial lines */ |
5ac48378 | 4746 | iter->seq.seq.len = save_len; |
b3806b43 | 4747 | break; |
088b1e42 | 4748 | } |
b91facc3 FW |
4749 | if (ret != TRACE_TYPE_NO_CONSUME) |
4750 | trace_consume(iter); | |
b3806b43 | 4751 | |
5ac48378 | 4752 | if (trace_seq_used(&iter->seq) >= cnt) |
b3806b43 | 4753 | break; |
ee5e51f5 JO |
4754 | |
4755 | /* | |
4756 | * Setting the full flag means we reached the trace_seq buffer | |
4757 | * size and we should leave by partial output condition above. | |
4758 | * One of the trace_seq_* functions is not used properly. | |
4759 | */ | |
4760 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
4761 | iter->ent->type); | |
b3806b43 | 4762 | } |
7e53bd42 | 4763 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4764 | trace_event_read_unlock(); |
b3806b43 | 4765 | |
b3806b43 | 4766 | /* Now copy what we have to the user */ |
6c6c2796 | 4767 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
5ac48378 | 4768 | if (iter->seq.seq.readpos >= trace_seq_used(&iter->seq)) |
f9520750 | 4769 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
4770 | |
4771 | /* | |
25985edc | 4772 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
4773 | * entries, go back to wait for more entries. |
4774 | */ | |
6c6c2796 | 4775 | if (sret == -EBUSY) |
9ff4b974 | 4776 | goto waitagain; |
b3806b43 | 4777 | |
107bad8b | 4778 | out: |
d7350c3f | 4779 | mutex_unlock(&iter->mutex); |
107bad8b | 4780 | |
6c6c2796 | 4781 | return sret; |
b3806b43 SR |
4782 | } |
4783 | ||
3c56819b EGM |
4784 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, |
4785 | unsigned int idx) | |
4786 | { | |
4787 | __free_page(spd->pages[idx]); | |
4788 | } | |
4789 | ||
28dfef8f | 4790 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 | 4791 | .can_merge = 0, |
34cd4998 | 4792 | .confirm = generic_pipe_buf_confirm, |
92fdd98c | 4793 | .release = generic_pipe_buf_release, |
34cd4998 SR |
4794 | .steal = generic_pipe_buf_steal, |
4795 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
4796 | }; |
4797 | ||
34cd4998 | 4798 | static size_t |
fa7c7f6e | 4799 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
4800 | { |
4801 | size_t count; | |
74f06bb7 | 4802 | int save_len; |
34cd4998 SR |
4803 | int ret; |
4804 | ||
4805 | /* Seq buffer is page-sized, exactly what we need. */ | |
4806 | for (;;) { | |
74f06bb7 | 4807 | save_len = iter->seq.seq.len; |
34cd4998 | 4808 | ret = print_trace_line(iter); |
74f06bb7 SRRH |
4809 | |
4810 | if (trace_seq_has_overflowed(&iter->seq)) { | |
4811 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
4812 | break; |
4813 | } | |
74f06bb7 SRRH |
4814 | |
4815 | /* | |
4816 | * This should not be hit, because it should only | |
4817 | * be set if the iter->seq overflowed. But check it | |
4818 | * anyway to be safe. | |
4819 | */ | |
34cd4998 | 4820 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
74f06bb7 SRRH |
4821 | iter->seq.seq.len = save_len; |
4822 | break; | |
4823 | } | |
4824 | ||
5ac48378 | 4825 | count = trace_seq_used(&iter->seq) - save_len; |
74f06bb7 SRRH |
4826 | if (rem < count) { |
4827 | rem = 0; | |
4828 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
4829 | break; |
4830 | } | |
4831 | ||
74e7ff8c LJ |
4832 | if (ret != TRACE_TYPE_NO_CONSUME) |
4833 | trace_consume(iter); | |
34cd4998 | 4834 | rem -= count; |
955b61e5 | 4835 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
4836 | rem = 0; |
4837 | iter->ent = NULL; | |
4838 | break; | |
4839 | } | |
4840 | } | |
4841 | ||
4842 | return rem; | |
4843 | } | |
4844 | ||
3c56819b EGM |
4845 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
4846 | loff_t *ppos, | |
4847 | struct pipe_inode_info *pipe, | |
4848 | size_t len, | |
4849 | unsigned int flags) | |
4850 | { | |
35f3d14d JA |
4851 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
4852 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
4853 | struct trace_iterator *iter = filp->private_data; |
4854 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
4855 | .pages = pages_def, |
4856 | .partial = partial_def, | |
34cd4998 | 4857 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 4858 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
4859 | .flags = flags, |
4860 | .ops = &tracing_pipe_buf_ops, | |
4861 | .spd_release = tracing_spd_release_pipe, | |
3c56819b EGM |
4862 | }; |
4863 | ssize_t ret; | |
34cd4998 | 4864 | size_t rem; |
3c56819b EGM |
4865 | unsigned int i; |
4866 | ||
35f3d14d JA |
4867 | if (splice_grow_spd(pipe, &spd)) |
4868 | return -ENOMEM; | |
4869 | ||
d7350c3f | 4870 | mutex_lock(&iter->mutex); |
3c56819b EGM |
4871 | |
4872 | if (iter->trace->splice_read) { | |
4873 | ret = iter->trace->splice_read(iter, filp, | |
4874 | ppos, pipe, len, flags); | |
4875 | if (ret) | |
34cd4998 | 4876 | goto out_err; |
3c56819b EGM |
4877 | } |
4878 | ||
4879 | ret = tracing_wait_pipe(filp); | |
4880 | if (ret <= 0) | |
34cd4998 | 4881 | goto out_err; |
3c56819b | 4882 | |
955b61e5 | 4883 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 4884 | ret = -EFAULT; |
34cd4998 | 4885 | goto out_err; |
3c56819b EGM |
4886 | } |
4887 | ||
4f535968 | 4888 | trace_event_read_lock(); |
7e53bd42 | 4889 | trace_access_lock(iter->cpu_file); |
4f535968 | 4890 | |
3c56819b | 4891 | /* Fill as many pages as possible. */ |
a786c06d | 4892 | for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) { |
35f3d14d JA |
4893 | spd.pages[i] = alloc_page(GFP_KERNEL); |
4894 | if (!spd.pages[i]) | |
34cd4998 | 4895 | break; |
3c56819b | 4896 | |
fa7c7f6e | 4897 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
4898 | |
4899 | /* Copy the data into the page, so we can start over. */ | |
4900 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 4901 | page_address(spd.pages[i]), |
5ac48378 | 4902 | trace_seq_used(&iter->seq)); |
3c56819b | 4903 | if (ret < 0) { |
35f3d14d | 4904 | __free_page(spd.pages[i]); |
3c56819b EGM |
4905 | break; |
4906 | } | |
35f3d14d | 4907 | spd.partial[i].offset = 0; |
5ac48378 | 4908 | spd.partial[i].len = trace_seq_used(&iter->seq); |
3c56819b | 4909 | |
f9520750 | 4910 | trace_seq_init(&iter->seq); |
3c56819b EGM |
4911 | } |
4912 | ||
7e53bd42 | 4913 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4914 | trace_event_read_unlock(); |
d7350c3f | 4915 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
4916 | |
4917 | spd.nr_pages = i; | |
4918 | ||
35f3d14d JA |
4919 | ret = splice_to_pipe(pipe, &spd); |
4920 | out: | |
047fe360 | 4921 | splice_shrink_spd(&spd); |
35f3d14d | 4922 | return ret; |
3c56819b | 4923 | |
34cd4998 | 4924 | out_err: |
d7350c3f | 4925 | mutex_unlock(&iter->mutex); |
35f3d14d | 4926 | goto out; |
3c56819b EGM |
4927 | } |
4928 | ||
a98a3c3f SR |
4929 | static ssize_t |
4930 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
4931 | size_t cnt, loff_t *ppos) | |
4932 | { | |
0bc392ee ON |
4933 | struct inode *inode = file_inode(filp); |
4934 | struct trace_array *tr = inode->i_private; | |
4935 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
4936 | char buf[64]; |
4937 | int r = 0; | |
4938 | ssize_t ret; | |
a98a3c3f | 4939 | |
db526ca3 | 4940 | mutex_lock(&trace_types_lock); |
438ced17 | 4941 | |
0bc392ee | 4942 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
4943 | int cpu, buf_size_same; |
4944 | unsigned long size; | |
4945 | ||
4946 | size = 0; | |
4947 | buf_size_same = 1; | |
4948 | /* check if all cpu sizes are same */ | |
4949 | for_each_tracing_cpu(cpu) { | |
4950 | /* fill in the size from first enabled cpu */ | |
4951 | if (size == 0) | |
12883efb SRRH |
4952 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
4953 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
4954 | buf_size_same = 0; |
4955 | break; | |
4956 | } | |
4957 | } | |
4958 | ||
4959 | if (buf_size_same) { | |
4960 | if (!ring_buffer_expanded) | |
4961 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
4962 | size >> 10, | |
4963 | trace_buf_size >> 10); | |
4964 | else | |
4965 | r = sprintf(buf, "%lu\n", size >> 10); | |
4966 | } else | |
4967 | r = sprintf(buf, "X\n"); | |
4968 | } else | |
0bc392ee | 4969 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10); |
438ced17 | 4970 | |
db526ca3 SR |
4971 | mutex_unlock(&trace_types_lock); |
4972 | ||
438ced17 VN |
4973 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
4974 | return ret; | |
a98a3c3f SR |
4975 | } |
4976 | ||
4977 | static ssize_t | |
4978 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
4979 | size_t cnt, loff_t *ppos) | |
4980 | { | |
0bc392ee ON |
4981 | struct inode *inode = file_inode(filp); |
4982 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 4983 | unsigned long val; |
4f271a2a | 4984 | int ret; |
a98a3c3f | 4985 | |
22fe9b54 PH |
4986 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4987 | if (ret) | |
c6caeeb1 | 4988 | return ret; |
a98a3c3f SR |
4989 | |
4990 | /* must have at least 1 entry */ | |
4991 | if (!val) | |
4992 | return -EINVAL; | |
4993 | ||
1696b2b0 SR |
4994 | /* value is in KB */ |
4995 | val <<= 10; | |
0bc392ee | 4996 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
4997 | if (ret < 0) |
4998 | return ret; | |
a98a3c3f | 4999 | |
cf8517cf | 5000 | *ppos += cnt; |
a98a3c3f | 5001 | |
4f271a2a VN |
5002 | return cnt; |
5003 | } | |
bf5e6519 | 5004 | |
f81ab074 VN |
5005 | static ssize_t |
5006 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
5007 | size_t cnt, loff_t *ppos) | |
5008 | { | |
5009 | struct trace_array *tr = filp->private_data; | |
5010 | char buf[64]; | |
5011 | int r, cpu; | |
5012 | unsigned long size = 0, expanded_size = 0; | |
5013 | ||
5014 | mutex_lock(&trace_types_lock); | |
5015 | for_each_tracing_cpu(cpu) { | |
12883efb | 5016 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
5017 | if (!ring_buffer_expanded) |
5018 | expanded_size += trace_buf_size >> 10; | |
5019 | } | |
5020 | if (ring_buffer_expanded) | |
5021 | r = sprintf(buf, "%lu\n", size); | |
5022 | else | |
5023 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
5024 | mutex_unlock(&trace_types_lock); | |
5025 | ||
5026 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5027 | } | |
5028 | ||
4f271a2a VN |
5029 | static ssize_t |
5030 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
5031 | size_t cnt, loff_t *ppos) | |
5032 | { | |
5033 | /* | |
5034 | * There is no need to read what the user has written, this function | |
5035 | * is just to make sure that there is no error when "echo" is used | |
5036 | */ | |
5037 | ||
5038 | *ppos += cnt; | |
a98a3c3f SR |
5039 | |
5040 | return cnt; | |
5041 | } | |
5042 | ||
4f271a2a VN |
5043 | static int |
5044 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
5045 | { | |
2b6080f2 SR |
5046 | struct trace_array *tr = inode->i_private; |
5047 | ||
cf30cf67 SR |
5048 | /* disable tracing ? */ |
5049 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
711e1243 | 5050 | tracer_tracing_off(tr); |
4f271a2a | 5051 | /* resize the ring buffer to 0 */ |
2b6080f2 | 5052 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 5053 | |
7b85af63 SRRH |
5054 | trace_array_put(tr); |
5055 | ||
4f271a2a VN |
5056 | return 0; |
5057 | } | |
5058 | ||
5bf9a1ee PP |
5059 | static ssize_t |
5060 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
5061 | size_t cnt, loff_t *fpos) | |
5062 | { | |
d696b58c | 5063 | unsigned long addr = (unsigned long)ubuf; |
2d71619c | 5064 | struct trace_array *tr = filp->private_data; |
d696b58c SR |
5065 | struct ring_buffer_event *event; |
5066 | struct ring_buffer *buffer; | |
5067 | struct print_entry *entry; | |
5068 | unsigned long irq_flags; | |
5069 | struct page *pages[2]; | |
6edb2a8a | 5070 | void *map_page[2]; |
d696b58c SR |
5071 | int nr_pages = 1; |
5072 | ssize_t written; | |
d696b58c SR |
5073 | int offset; |
5074 | int size; | |
5075 | int len; | |
5076 | int ret; | |
6edb2a8a | 5077 | int i; |
5bf9a1ee | 5078 | |
c76f0694 | 5079 | if (tracing_disabled) |
5bf9a1ee PP |
5080 | return -EINVAL; |
5081 | ||
5224c3a3 MSB |
5082 | if (!(trace_flags & TRACE_ITER_MARKERS)) |
5083 | return -EINVAL; | |
5084 | ||
5bf9a1ee PP |
5085 | if (cnt > TRACE_BUF_SIZE) |
5086 | cnt = TRACE_BUF_SIZE; | |
5087 | ||
d696b58c SR |
5088 | /* |
5089 | * Userspace is injecting traces into the kernel trace buffer. | |
5090 | * We want to be as non intrusive as possible. | |
5091 | * To do so, we do not want to allocate any special buffers | |
5092 | * or take any locks, but instead write the userspace data | |
5093 | * straight into the ring buffer. | |
5094 | * | |
5095 | * First we need to pin the userspace buffer into memory, | |
5096 | * which, most likely it is, because it just referenced it. | |
5097 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
5098 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
5099 | * pages directly. We then write the data directly into the | |
5100 | * ring buffer. | |
5101 | */ | |
5102 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 5103 | |
d696b58c SR |
5104 | /* check if we cross pages */ |
5105 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
5106 | nr_pages = 2; | |
5107 | ||
5108 | offset = addr & (PAGE_SIZE - 1); | |
5109 | addr &= PAGE_MASK; | |
5110 | ||
5111 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
5112 | if (ret < nr_pages) { | |
5113 | while (--ret >= 0) | |
5114 | put_page(pages[ret]); | |
5115 | written = -EFAULT; | |
5116 | goto out; | |
5bf9a1ee | 5117 | } |
d696b58c | 5118 | |
6edb2a8a SR |
5119 | for (i = 0; i < nr_pages; i++) |
5120 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
5121 | |
5122 | local_save_flags(irq_flags); | |
5123 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
2d71619c | 5124 | buffer = tr->trace_buffer.buffer; |
d696b58c SR |
5125 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
5126 | irq_flags, preempt_count()); | |
5127 | if (!event) { | |
5128 | /* Ring buffer disabled, return as if not open for write */ | |
5129 | written = -EBADF; | |
5130 | goto out_unlock; | |
5bf9a1ee | 5131 | } |
d696b58c SR |
5132 | |
5133 | entry = ring_buffer_event_data(event); | |
5134 | entry->ip = _THIS_IP_; | |
5135 | ||
5136 | if (nr_pages == 2) { | |
5137 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
5138 | memcpy(&entry->buf, map_page[0] + offset, len); |
5139 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 5140 | } else |
6edb2a8a | 5141 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 5142 | |
d696b58c SR |
5143 | if (entry->buf[cnt - 1] != '\n') { |
5144 | entry->buf[cnt] = '\n'; | |
5145 | entry->buf[cnt + 1] = '\0'; | |
5146 | } else | |
5147 | entry->buf[cnt] = '\0'; | |
5148 | ||
7ffbd48d | 5149 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 5150 | |
d696b58c | 5151 | written = cnt; |
5bf9a1ee | 5152 | |
d696b58c | 5153 | *fpos += written; |
1aa54bca | 5154 | |
d696b58c | 5155 | out_unlock: |
7215853e | 5156 | for (i = nr_pages - 1; i >= 0; i--) { |
6edb2a8a SR |
5157 | kunmap_atomic(map_page[i]); |
5158 | put_page(pages[i]); | |
5159 | } | |
d696b58c | 5160 | out: |
1aa54bca | 5161 | return written; |
5bf9a1ee PP |
5162 | } |
5163 | ||
13f16d20 | 5164 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 5165 | { |
2b6080f2 | 5166 | struct trace_array *tr = m->private; |
5079f326 Z |
5167 | int i; |
5168 | ||
5169 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 5170 | seq_printf(m, |
5079f326 | 5171 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
5172 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
5173 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 5174 | seq_putc(m, '\n'); |
5079f326 | 5175 | |
13f16d20 | 5176 | return 0; |
5079f326 Z |
5177 | } |
5178 | ||
e1e232ca | 5179 | static int tracing_set_clock(struct trace_array *tr, const char *clockstr) |
5079f326 | 5180 | { |
5079f326 Z |
5181 | int i; |
5182 | ||
5079f326 Z |
5183 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { |
5184 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
5185 | break; | |
5186 | } | |
5187 | if (i == ARRAY_SIZE(trace_clocks)) | |
5188 | return -EINVAL; | |
5189 | ||
5079f326 Z |
5190 | mutex_lock(&trace_types_lock); |
5191 | ||
2b6080f2 SR |
5192 | tr->clock_id = i; |
5193 | ||
12883efb | 5194 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 5195 | |
60303ed3 DS |
5196 | /* |
5197 | * New clock may not be consistent with the previous clock. | |
5198 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
5199 | */ | |
9457158b | 5200 | tracing_reset_online_cpus(&tr->trace_buffer); |
12883efb SRRH |
5201 | |
5202 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5203 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) | |
5204 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); | |
9457158b | 5205 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 5206 | #endif |
60303ed3 | 5207 | |
5079f326 Z |
5208 | mutex_unlock(&trace_types_lock); |
5209 | ||
e1e232ca SR |
5210 | return 0; |
5211 | } | |
5212 | ||
5213 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
5214 | size_t cnt, loff_t *fpos) | |
5215 | { | |
5216 | struct seq_file *m = filp->private_data; | |
5217 | struct trace_array *tr = m->private; | |
5218 | char buf[64]; | |
5219 | const char *clockstr; | |
5220 | int ret; | |
5221 | ||
5222 | if (cnt >= sizeof(buf)) | |
5223 | return -EINVAL; | |
5224 | ||
5225 | if (copy_from_user(&buf, ubuf, cnt)) | |
5226 | return -EFAULT; | |
5227 | ||
5228 | buf[cnt] = 0; | |
5229 | ||
5230 | clockstr = strstrip(buf); | |
5231 | ||
5232 | ret = tracing_set_clock(tr, clockstr); | |
5233 | if (ret) | |
5234 | return ret; | |
5235 | ||
5079f326 Z |
5236 | *fpos += cnt; |
5237 | ||
5238 | return cnt; | |
5239 | } | |
5240 | ||
13f16d20 LZ |
5241 | static int tracing_clock_open(struct inode *inode, struct file *file) |
5242 | { | |
7b85af63 SRRH |
5243 | struct trace_array *tr = inode->i_private; |
5244 | int ret; | |
5245 | ||
13f16d20 LZ |
5246 | if (tracing_disabled) |
5247 | return -ENODEV; | |
2b6080f2 | 5248 | |
7b85af63 SRRH |
5249 | if (trace_array_get(tr)) |
5250 | return -ENODEV; | |
5251 | ||
5252 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
5253 | if (ret < 0) | |
5254 | trace_array_put(tr); | |
5255 | ||
5256 | return ret; | |
13f16d20 LZ |
5257 | } |
5258 | ||
6de58e62 SRRH |
5259 | struct ftrace_buffer_info { |
5260 | struct trace_iterator iter; | |
5261 | void *spare; | |
5262 | unsigned int read; | |
5263 | }; | |
5264 | ||
debdd57f HT |
5265 | #ifdef CONFIG_TRACER_SNAPSHOT |
5266 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
5267 | { | |
6484c71c | 5268 | struct trace_array *tr = inode->i_private; |
debdd57f | 5269 | struct trace_iterator *iter; |
2b6080f2 | 5270 | struct seq_file *m; |
debdd57f HT |
5271 | int ret = 0; |
5272 | ||
ff451961 SRRH |
5273 | if (trace_array_get(tr) < 0) |
5274 | return -ENODEV; | |
5275 | ||
debdd57f | 5276 | if (file->f_mode & FMODE_READ) { |
6484c71c | 5277 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
5278 | if (IS_ERR(iter)) |
5279 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
5280 | } else { |
5281 | /* Writes still need the seq_file to hold the private data */ | |
f77d09a3 | 5282 | ret = -ENOMEM; |
2b6080f2 SR |
5283 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
5284 | if (!m) | |
f77d09a3 | 5285 | goto out; |
2b6080f2 SR |
5286 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
5287 | if (!iter) { | |
5288 | kfree(m); | |
f77d09a3 | 5289 | goto out; |
2b6080f2 | 5290 | } |
f77d09a3 AL |
5291 | ret = 0; |
5292 | ||
ff451961 | 5293 | iter->tr = tr; |
6484c71c ON |
5294 | iter->trace_buffer = &tr->max_buffer; |
5295 | iter->cpu_file = tracing_get_cpu(inode); | |
2b6080f2 SR |
5296 | m->private = iter; |
5297 | file->private_data = m; | |
debdd57f | 5298 | } |
f77d09a3 | 5299 | out: |
ff451961 SRRH |
5300 | if (ret < 0) |
5301 | trace_array_put(tr); | |
5302 | ||
debdd57f HT |
5303 | return ret; |
5304 | } | |
5305 | ||
5306 | static ssize_t | |
5307 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5308 | loff_t *ppos) | |
5309 | { | |
2b6080f2 SR |
5310 | struct seq_file *m = filp->private_data; |
5311 | struct trace_iterator *iter = m->private; | |
5312 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
5313 | unsigned long val; |
5314 | int ret; | |
5315 | ||
5316 | ret = tracing_update_buffers(); | |
5317 | if (ret < 0) | |
5318 | return ret; | |
5319 | ||
5320 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5321 | if (ret) | |
5322 | return ret; | |
5323 | ||
5324 | mutex_lock(&trace_types_lock); | |
5325 | ||
2b6080f2 | 5326 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
5327 | ret = -EBUSY; |
5328 | goto out; | |
5329 | } | |
5330 | ||
5331 | switch (val) { | |
5332 | case 0: | |
f1affcaa SRRH |
5333 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
5334 | ret = -EINVAL; | |
5335 | break; | |
debdd57f | 5336 | } |
3209cff4 SRRH |
5337 | if (tr->allocated_snapshot) |
5338 | free_snapshot(tr); | |
debdd57f HT |
5339 | break; |
5340 | case 1: | |
f1affcaa SRRH |
5341 | /* Only allow per-cpu swap if the ring buffer supports it */ |
5342 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
5343 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
5344 | ret = -EINVAL; | |
5345 | break; | |
5346 | } | |
5347 | #endif | |
45ad21ca | 5348 | if (!tr->allocated_snapshot) { |
3209cff4 | 5349 | ret = alloc_snapshot(tr); |
debdd57f HT |
5350 | if (ret < 0) |
5351 | break; | |
debdd57f | 5352 | } |
debdd57f HT |
5353 | local_irq_disable(); |
5354 | /* Now, we're going to swap */ | |
f1affcaa | 5355 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 5356 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 5357 | else |
ce9bae55 | 5358 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
5359 | local_irq_enable(); |
5360 | break; | |
5361 | default: | |
45ad21ca | 5362 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
5363 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
5364 | tracing_reset_online_cpus(&tr->max_buffer); | |
5365 | else | |
5366 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
5367 | } | |
debdd57f HT |
5368 | break; |
5369 | } | |
5370 | ||
5371 | if (ret >= 0) { | |
5372 | *ppos += cnt; | |
5373 | ret = cnt; | |
5374 | } | |
5375 | out: | |
5376 | mutex_unlock(&trace_types_lock); | |
5377 | return ret; | |
5378 | } | |
2b6080f2 SR |
5379 | |
5380 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
5381 | { | |
5382 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
5383 | int ret; |
5384 | ||
5385 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
5386 | |
5387 | if (file->f_mode & FMODE_READ) | |
ff451961 | 5388 | return ret; |
2b6080f2 SR |
5389 | |
5390 | /* If write only, the seq_file is just a stub */ | |
5391 | if (m) | |
5392 | kfree(m->private); | |
5393 | kfree(m); | |
5394 | ||
5395 | return 0; | |
5396 | } | |
5397 | ||
6de58e62 SRRH |
5398 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
5399 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5400 | size_t count, loff_t *ppos); | |
5401 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
5402 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5403 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
5404 | ||
5405 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
5406 | { | |
5407 | struct ftrace_buffer_info *info; | |
5408 | int ret; | |
5409 | ||
5410 | ret = tracing_buffers_open(inode, filp); | |
5411 | if (ret < 0) | |
5412 | return ret; | |
5413 | ||
5414 | info = filp->private_data; | |
5415 | ||
5416 | if (info->iter.trace->use_max_tr) { | |
5417 | tracing_buffers_release(inode, filp); | |
5418 | return -EBUSY; | |
5419 | } | |
5420 | ||
5421 | info->iter.snapshot = true; | |
5422 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
5423 | ||
5424 | return ret; | |
5425 | } | |
5426 | ||
debdd57f HT |
5427 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5428 | ||
5429 | ||
6508fa76 SF |
5430 | static const struct file_operations tracing_thresh_fops = { |
5431 | .open = tracing_open_generic, | |
5432 | .read = tracing_thresh_read, | |
5433 | .write = tracing_thresh_write, | |
5434 | .llseek = generic_file_llseek, | |
5435 | }; | |
5436 | ||
5e2336a0 | 5437 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
5438 | .open = tracing_open_generic, |
5439 | .read = tracing_max_lat_read, | |
5440 | .write = tracing_max_lat_write, | |
b444786f | 5441 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5442 | }; |
5443 | ||
5e2336a0 | 5444 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
5445 | .open = tracing_open_generic, |
5446 | .read = tracing_set_trace_read, | |
5447 | .write = tracing_set_trace_write, | |
b444786f | 5448 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5449 | }; |
5450 | ||
5e2336a0 | 5451 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 5452 | .open = tracing_open_pipe, |
2a2cc8f7 | 5453 | .poll = tracing_poll_pipe, |
4bf39a94 | 5454 | .read = tracing_read_pipe, |
3c56819b | 5455 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 5456 | .release = tracing_release_pipe, |
b444786f | 5457 | .llseek = no_llseek, |
b3806b43 SR |
5458 | }; |
5459 | ||
5e2336a0 | 5460 | static const struct file_operations tracing_entries_fops = { |
0bc392ee | 5461 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
5462 | .read = tracing_entries_read, |
5463 | .write = tracing_entries_write, | |
b444786f | 5464 | .llseek = generic_file_llseek, |
0bc392ee | 5465 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
5466 | }; |
5467 | ||
f81ab074 | 5468 | static const struct file_operations tracing_total_entries_fops = { |
7b85af63 | 5469 | .open = tracing_open_generic_tr, |
f81ab074 VN |
5470 | .read = tracing_total_entries_read, |
5471 | .llseek = generic_file_llseek, | |
7b85af63 | 5472 | .release = tracing_release_generic_tr, |
f81ab074 VN |
5473 | }; |
5474 | ||
4f271a2a | 5475 | static const struct file_operations tracing_free_buffer_fops = { |
7b85af63 | 5476 | .open = tracing_open_generic_tr, |
4f271a2a VN |
5477 | .write = tracing_free_buffer_write, |
5478 | .release = tracing_free_buffer_release, | |
5479 | }; | |
5480 | ||
5e2336a0 | 5481 | static const struct file_operations tracing_mark_fops = { |
7b85af63 | 5482 | .open = tracing_open_generic_tr, |
5bf9a1ee | 5483 | .write = tracing_mark_write, |
b444786f | 5484 | .llseek = generic_file_llseek, |
7b85af63 | 5485 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
5486 | }; |
5487 | ||
5079f326 | 5488 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
5489 | .open = tracing_clock_open, |
5490 | .read = seq_read, | |
5491 | .llseek = seq_lseek, | |
7b85af63 | 5492 | .release = tracing_single_release_tr, |
5079f326 Z |
5493 | .write = tracing_clock_write, |
5494 | }; | |
5495 | ||
debdd57f HT |
5496 | #ifdef CONFIG_TRACER_SNAPSHOT |
5497 | static const struct file_operations snapshot_fops = { | |
5498 | .open = tracing_snapshot_open, | |
5499 | .read = seq_read, | |
5500 | .write = tracing_snapshot_write, | |
098c879e | 5501 | .llseek = tracing_lseek, |
2b6080f2 | 5502 | .release = tracing_snapshot_release, |
debdd57f | 5503 | }; |
debdd57f | 5504 | |
6de58e62 SRRH |
5505 | static const struct file_operations snapshot_raw_fops = { |
5506 | .open = snapshot_raw_open, | |
5507 | .read = tracing_buffers_read, | |
5508 | .release = tracing_buffers_release, | |
5509 | .splice_read = tracing_buffers_splice_read, | |
5510 | .llseek = no_llseek, | |
2cadf913 SR |
5511 | }; |
5512 | ||
6de58e62 SRRH |
5513 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5514 | ||
2cadf913 SR |
5515 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
5516 | { | |
46ef2be0 | 5517 | struct trace_array *tr = inode->i_private; |
2cadf913 | 5518 | struct ftrace_buffer_info *info; |
7b85af63 | 5519 | int ret; |
2cadf913 SR |
5520 | |
5521 | if (tracing_disabled) | |
5522 | return -ENODEV; | |
5523 | ||
7b85af63 SRRH |
5524 | if (trace_array_get(tr) < 0) |
5525 | return -ENODEV; | |
5526 | ||
2cadf913 | 5527 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
7b85af63 SRRH |
5528 | if (!info) { |
5529 | trace_array_put(tr); | |
2cadf913 | 5530 | return -ENOMEM; |
7b85af63 | 5531 | } |
2cadf913 | 5532 | |
a695cb58 SRRH |
5533 | mutex_lock(&trace_types_lock); |
5534 | ||
cc60cdc9 | 5535 | info->iter.tr = tr; |
46ef2be0 | 5536 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 5537 | info->iter.trace = tr->current_trace; |
12883efb | 5538 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 5539 | info->spare = NULL; |
2cadf913 | 5540 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 5541 | info->read = (unsigned int)-1; |
2cadf913 SR |
5542 | |
5543 | filp->private_data = info; | |
5544 | ||
cf6ab6d9 SRRH |
5545 | tr->current_trace->ref++; |
5546 | ||
a695cb58 SRRH |
5547 | mutex_unlock(&trace_types_lock); |
5548 | ||
7b85af63 SRRH |
5549 | ret = nonseekable_open(inode, filp); |
5550 | if (ret < 0) | |
5551 | trace_array_put(tr); | |
5552 | ||
5553 | return ret; | |
2cadf913 SR |
5554 | } |
5555 | ||
cc60cdc9 SR |
5556 | static unsigned int |
5557 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
5558 | { | |
5559 | struct ftrace_buffer_info *info = filp->private_data; | |
5560 | struct trace_iterator *iter = &info->iter; | |
5561 | ||
5562 | return trace_poll(iter, filp, poll_table); | |
5563 | } | |
5564 | ||
2cadf913 SR |
5565 | static ssize_t |
5566 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5567 | size_t count, loff_t *ppos) | |
5568 | { | |
5569 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 5570 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5571 | ssize_t ret; |
6de58e62 | 5572 | ssize_t size; |
2cadf913 | 5573 | |
2dc5d12b SR |
5574 | if (!count) |
5575 | return 0; | |
5576 | ||
6de58e62 | 5577 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
5578 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
5579 | return -EBUSY; | |
6de58e62 SRRH |
5580 | #endif |
5581 | ||
ddd538f3 | 5582 | if (!info->spare) |
12883efb SRRH |
5583 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
5584 | iter->cpu_file); | |
ddd538f3 | 5585 | if (!info->spare) |
d716ff71 | 5586 | return -ENOMEM; |
ddd538f3 | 5587 | |
2cadf913 SR |
5588 | /* Do we have previous read data to read? */ |
5589 | if (info->read < PAGE_SIZE) | |
5590 | goto read; | |
5591 | ||
b627344f | 5592 | again: |
cc60cdc9 | 5593 | trace_access_lock(iter->cpu_file); |
12883efb | 5594 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
5595 | &info->spare, |
5596 | count, | |
cc60cdc9 SR |
5597 | iter->cpu_file, 0); |
5598 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 5599 | |
b627344f SR |
5600 | if (ret < 0) { |
5601 | if (trace_empty(iter)) { | |
d716ff71 SRRH |
5602 | if ((filp->f_flags & O_NONBLOCK)) |
5603 | return -EAGAIN; | |
5604 | ||
e30f53aa | 5605 | ret = wait_on_pipe(iter, false); |
d716ff71 SRRH |
5606 | if (ret) |
5607 | return ret; | |
5608 | ||
b627344f SR |
5609 | goto again; |
5610 | } | |
d716ff71 | 5611 | return 0; |
b627344f | 5612 | } |
436fc280 | 5613 | |
436fc280 | 5614 | info->read = 0; |
b627344f | 5615 | read: |
2cadf913 SR |
5616 | size = PAGE_SIZE - info->read; |
5617 | if (size > count) | |
5618 | size = count; | |
5619 | ||
5620 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
d716ff71 SRRH |
5621 | if (ret == size) |
5622 | return -EFAULT; | |
5623 | ||
2dc5d12b SR |
5624 | size -= ret; |
5625 | ||
2cadf913 SR |
5626 | *ppos += size; |
5627 | info->read += size; | |
5628 | ||
5629 | return size; | |
5630 | } | |
5631 | ||
5632 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
5633 | { | |
5634 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5635 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 5636 | |
a695cb58 SRRH |
5637 | mutex_lock(&trace_types_lock); |
5638 | ||
cf6ab6d9 SRRH |
5639 | iter->tr->current_trace->ref--; |
5640 | ||
ff451961 | 5641 | __trace_array_put(iter->tr); |
2cadf913 | 5642 | |
ddd538f3 | 5643 | if (info->spare) |
12883efb | 5644 | ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); |
2cadf913 SR |
5645 | kfree(info); |
5646 | ||
a695cb58 SRRH |
5647 | mutex_unlock(&trace_types_lock); |
5648 | ||
2cadf913 SR |
5649 | return 0; |
5650 | } | |
5651 | ||
5652 | struct buffer_ref { | |
5653 | struct ring_buffer *buffer; | |
5654 | void *page; | |
5655 | int ref; | |
5656 | }; | |
5657 | ||
5658 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
5659 | struct pipe_buffer *buf) | |
5660 | { | |
5661 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5662 | ||
5663 | if (--ref->ref) | |
5664 | return; | |
5665 | ||
5666 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5667 | kfree(ref); | |
5668 | buf->private = 0; | |
5669 | } | |
5670 | ||
2cadf913 SR |
5671 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
5672 | struct pipe_buffer *buf) | |
5673 | { | |
5674 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
5675 | ||
5676 | ref->ref++; | |
5677 | } | |
5678 | ||
5679 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 5680 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 | 5681 | .can_merge = 0, |
2cadf913 SR |
5682 | .confirm = generic_pipe_buf_confirm, |
5683 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 5684 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
5685 | .get = buffer_pipe_buf_get, |
5686 | }; | |
5687 | ||
5688 | /* | |
5689 | * Callback from splice_to_pipe(), if we need to release some pages | |
5690 | * at the end of the spd in case we error'ed out in filling the pipe. | |
5691 | */ | |
5692 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
5693 | { | |
5694 | struct buffer_ref *ref = | |
5695 | (struct buffer_ref *)spd->partial[i].private; | |
5696 | ||
5697 | if (--ref->ref) | |
5698 | return; | |
5699 | ||
5700 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
5701 | kfree(ref); | |
5702 | spd->partial[i].private = 0; | |
5703 | } | |
5704 | ||
5705 | static ssize_t | |
5706 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5707 | struct pipe_inode_info *pipe, size_t len, | |
5708 | unsigned int flags) | |
5709 | { | |
5710 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 5711 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
5712 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
5713 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 5714 | struct splice_pipe_desc spd = { |
35f3d14d JA |
5715 | .pages = pages_def, |
5716 | .partial = partial_def, | |
047fe360 | 5717 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
5718 | .flags = flags, |
5719 | .ops = &buffer_pipe_buf_ops, | |
5720 | .spd_release = buffer_spd_release, | |
5721 | }; | |
5722 | struct buffer_ref *ref; | |
93459c6c | 5723 | int entries, size, i; |
07906da7 | 5724 | ssize_t ret = 0; |
2cadf913 | 5725 | |
6de58e62 | 5726 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
5727 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
5728 | return -EBUSY; | |
6de58e62 SRRH |
5729 | #endif |
5730 | ||
d716ff71 SRRH |
5731 | if (splice_grow_spd(pipe, &spd)) |
5732 | return -ENOMEM; | |
35f3d14d | 5733 | |
d716ff71 SRRH |
5734 | if (*ppos & (PAGE_SIZE - 1)) |
5735 | return -EINVAL; | |
93cfb3c9 LJ |
5736 | |
5737 | if (len & (PAGE_SIZE - 1)) { | |
d716ff71 SRRH |
5738 | if (len < PAGE_SIZE) |
5739 | return -EINVAL; | |
93cfb3c9 LJ |
5740 | len &= PAGE_MASK; |
5741 | } | |
5742 | ||
cc60cdc9 SR |
5743 | again: |
5744 | trace_access_lock(iter->cpu_file); | |
12883efb | 5745 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 5746 | |
a786c06d | 5747 | for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
5748 | struct page *page; |
5749 | int r; | |
5750 | ||
5751 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
07906da7 RV |
5752 | if (!ref) { |
5753 | ret = -ENOMEM; | |
2cadf913 | 5754 | break; |
07906da7 | 5755 | } |
2cadf913 | 5756 | |
7267fa68 | 5757 | ref->ref = 1; |
12883efb | 5758 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 5759 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
2cadf913 | 5760 | if (!ref->page) { |
07906da7 | 5761 | ret = -ENOMEM; |
2cadf913 SR |
5762 | kfree(ref); |
5763 | break; | |
5764 | } | |
5765 | ||
5766 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 5767 | len, iter->cpu_file, 1); |
2cadf913 | 5768 | if (r < 0) { |
7ea59064 | 5769 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
5770 | kfree(ref); |
5771 | break; | |
5772 | } | |
5773 | ||
5774 | /* | |
5775 | * zero out any left over data, this is going to | |
5776 | * user land. | |
5777 | */ | |
5778 | size = ring_buffer_page_len(ref->page); | |
5779 | if (size < PAGE_SIZE) | |
5780 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
5781 | ||
5782 | page = virt_to_page(ref->page); | |
5783 | ||
5784 | spd.pages[i] = page; | |
5785 | spd.partial[i].len = PAGE_SIZE; | |
5786 | spd.partial[i].offset = 0; | |
5787 | spd.partial[i].private = (unsigned long)ref; | |
5788 | spd.nr_pages++; | |
93cfb3c9 | 5789 | *ppos += PAGE_SIZE; |
93459c6c | 5790 | |
12883efb | 5791 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
5792 | } |
5793 | ||
cc60cdc9 | 5794 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
5795 | spd.nr_pages = i; |
5796 | ||
5797 | /* did we read anything? */ | |
5798 | if (!spd.nr_pages) { | |
07906da7 | 5799 | if (ret) |
d716ff71 SRRH |
5800 | return ret; |
5801 | ||
5802 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) | |
5803 | return -EAGAIN; | |
07906da7 | 5804 | |
e30f53aa | 5805 | ret = wait_on_pipe(iter, true); |
8b8b3683 | 5806 | if (ret) |
d716ff71 | 5807 | return ret; |
e30f53aa | 5808 | |
cc60cdc9 | 5809 | goto again; |
2cadf913 SR |
5810 | } |
5811 | ||
5812 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 5813 | splice_shrink_spd(&spd); |
6de58e62 | 5814 | |
2cadf913 SR |
5815 | return ret; |
5816 | } | |
5817 | ||
5818 | static const struct file_operations tracing_buffers_fops = { | |
5819 | .open = tracing_buffers_open, | |
5820 | .read = tracing_buffers_read, | |
cc60cdc9 | 5821 | .poll = tracing_buffers_poll, |
2cadf913 SR |
5822 | .release = tracing_buffers_release, |
5823 | .splice_read = tracing_buffers_splice_read, | |
5824 | .llseek = no_llseek, | |
5825 | }; | |
5826 | ||
c8d77183 SR |
5827 | static ssize_t |
5828 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
5829 | size_t count, loff_t *ppos) | |
5830 | { | |
4d3435b8 ON |
5831 | struct inode *inode = file_inode(filp); |
5832 | struct trace_array *tr = inode->i_private; | |
12883efb | 5833 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
4d3435b8 | 5834 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
5835 | struct trace_seq *s; |
5836 | unsigned long cnt; | |
c64e148a VN |
5837 | unsigned long long t; |
5838 | unsigned long usec_rem; | |
c8d77183 | 5839 | |
e4f2d10f | 5840 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 5841 | if (!s) |
a646365c | 5842 | return -ENOMEM; |
c8d77183 SR |
5843 | |
5844 | trace_seq_init(s); | |
5845 | ||
12883efb | 5846 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5847 | trace_seq_printf(s, "entries: %ld\n", cnt); |
5848 | ||
12883efb | 5849 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5850 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
5851 | ||
12883efb | 5852 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
5853 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
5854 | ||
12883efb | 5855 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
5856 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
5857 | ||
58e8eedf | 5858 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 5859 | /* local or global for trace_clock */ |
12883efb | 5860 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
5861 | usec_rem = do_div(t, USEC_PER_SEC); |
5862 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
5863 | t, usec_rem); | |
5864 | ||
12883efb | 5865 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
5866 | usec_rem = do_div(t, USEC_PER_SEC); |
5867 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
5868 | } else { | |
5869 | /* counter or tsc mode for trace_clock */ | |
5870 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 5871 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 5872 | |
11043d8b | 5873 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 5874 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 5875 | } |
c64e148a | 5876 | |
12883efb | 5877 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
5878 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
5879 | ||
12883efb | 5880 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
5881 | trace_seq_printf(s, "read events: %ld\n", cnt); |
5882 | ||
5ac48378 SRRH |
5883 | count = simple_read_from_buffer(ubuf, count, ppos, |
5884 | s->buffer, trace_seq_used(s)); | |
c8d77183 SR |
5885 | |
5886 | kfree(s); | |
5887 | ||
5888 | return count; | |
5889 | } | |
5890 | ||
5891 | static const struct file_operations tracing_stats_fops = { | |
4d3435b8 | 5892 | .open = tracing_open_generic_tr, |
c8d77183 | 5893 | .read = tracing_stats_read, |
b444786f | 5894 | .llseek = generic_file_llseek, |
4d3435b8 | 5895 | .release = tracing_release_generic_tr, |
c8d77183 SR |
5896 | }; |
5897 | ||
bc0c38d1 SR |
5898 | #ifdef CONFIG_DYNAMIC_FTRACE |
5899 | ||
b807c3d0 SR |
5900 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
5901 | { | |
5902 | return 0; | |
5903 | } | |
5904 | ||
bc0c38d1 | 5905 | static ssize_t |
b807c3d0 | 5906 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
5907 | size_t cnt, loff_t *ppos) |
5908 | { | |
a26a2a27 SR |
5909 | static char ftrace_dyn_info_buffer[1024]; |
5910 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 5911 | unsigned long *p = filp->private_data; |
b807c3d0 | 5912 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 5913 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
5914 | int r; |
5915 | ||
b807c3d0 SR |
5916 | mutex_lock(&dyn_info_mutex); |
5917 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 5918 | |
a26a2a27 | 5919 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
5920 | buf[r++] = '\n'; |
5921 | ||
5922 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5923 | ||
5924 | mutex_unlock(&dyn_info_mutex); | |
5925 | ||
5926 | return r; | |
bc0c38d1 SR |
5927 | } |
5928 | ||
5e2336a0 | 5929 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 5930 | .open = tracing_open_generic, |
b807c3d0 | 5931 | .read = tracing_read_dyn_info, |
b444786f | 5932 | .llseek = generic_file_llseek, |
bc0c38d1 | 5933 | }; |
77fd5c15 | 5934 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 5935 | |
77fd5c15 SRRH |
5936 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
5937 | static void | |
5938 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
5939 | { | |
5940 | tracing_snapshot(); | |
5941 | } | |
bc0c38d1 | 5942 | |
77fd5c15 SRRH |
5943 | static void |
5944 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
bc0c38d1 | 5945 | { |
77fd5c15 SRRH |
5946 | unsigned long *count = (long *)data; |
5947 | ||
5948 | if (!*count) | |
5949 | return; | |
bc0c38d1 | 5950 | |
77fd5c15 SRRH |
5951 | if (*count != -1) |
5952 | (*count)--; | |
5953 | ||
5954 | tracing_snapshot(); | |
5955 | } | |
5956 | ||
5957 | static int | |
5958 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
5959 | struct ftrace_probe_ops *ops, void *data) | |
5960 | { | |
5961 | long count = (long)data; | |
5962 | ||
5963 | seq_printf(m, "%ps:", (void *)ip); | |
5964 | ||
fa6f0cc7 | 5965 | seq_puts(m, "snapshot"); |
77fd5c15 SRRH |
5966 | |
5967 | if (count == -1) | |
fa6f0cc7 | 5968 | seq_puts(m, ":unlimited\n"); |
77fd5c15 SRRH |
5969 | else |
5970 | seq_printf(m, ":count=%ld\n", count); | |
5971 | ||
5972 | return 0; | |
5973 | } | |
5974 | ||
5975 | static struct ftrace_probe_ops snapshot_probe_ops = { | |
5976 | .func = ftrace_snapshot, | |
5977 | .print = ftrace_snapshot_print, | |
5978 | }; | |
5979 | ||
5980 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
5981 | .func = ftrace_count_snapshot, | |
5982 | .print = ftrace_snapshot_print, | |
5983 | }; | |
5984 | ||
5985 | static int | |
5986 | ftrace_trace_snapshot_callback(struct ftrace_hash *hash, | |
5987 | char *glob, char *cmd, char *param, int enable) | |
5988 | { | |
5989 | struct ftrace_probe_ops *ops; | |
5990 | void *count = (void *)-1; | |
5991 | char *number; | |
5992 | int ret; | |
5993 | ||
5994 | /* hash funcs only work with set_ftrace_filter */ | |
5995 | if (!enable) | |
5996 | return -EINVAL; | |
5997 | ||
5998 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
5999 | ||
6000 | if (glob[0] == '!') { | |
6001 | unregister_ftrace_function_probe_func(glob+1, ops); | |
6002 | return 0; | |
6003 | } | |
6004 | ||
6005 | if (!param) | |
6006 | goto out_reg; | |
6007 | ||
6008 | number = strsep(¶m, ":"); | |
6009 | ||
6010 | if (!strlen(number)) | |
6011 | goto out_reg; | |
6012 | ||
6013 | /* | |
6014 | * We use the callback data field (which is a pointer) | |
6015 | * as our counter. | |
6016 | */ | |
6017 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
6018 | if (ret) | |
6019 | return ret; | |
6020 | ||
6021 | out_reg: | |
6022 | ret = register_ftrace_function_probe(glob, ops, count); | |
6023 | ||
6024 | if (ret >= 0) | |
6025 | alloc_snapshot(&global_trace); | |
6026 | ||
6027 | return ret < 0 ? ret : 0; | |
6028 | } | |
6029 | ||
6030 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
6031 | .name = "snapshot", | |
6032 | .func = ftrace_trace_snapshot_callback, | |
6033 | }; | |
6034 | ||
38de93ab | 6035 | static __init int register_snapshot_cmd(void) |
77fd5c15 SRRH |
6036 | { |
6037 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
6038 | } | |
6039 | #else | |
38de93ab | 6040 | static inline __init int register_snapshot_cmd(void) { return 0; } |
77fd5c15 | 6041 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ |
bc0c38d1 | 6042 | |
7eeafbca | 6043 | static struct dentry *tracing_get_dentry(struct trace_array *tr) |
bc0c38d1 | 6044 | { |
8434dc93 SRRH |
6045 | if (WARN_ON(!tr->dir)) |
6046 | return ERR_PTR(-ENODEV); | |
6047 | ||
6048 | /* Top directory uses NULL as the parent */ | |
6049 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
6050 | return NULL; | |
6051 | ||
6052 | /* All sub buffers have a descriptor */ | |
2b6080f2 | 6053 | return tr->dir; |
bc0c38d1 SR |
6054 | } |
6055 | ||
2b6080f2 | 6056 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 6057 | { |
b04cc6b1 FW |
6058 | struct dentry *d_tracer; |
6059 | ||
2b6080f2 SR |
6060 | if (tr->percpu_dir) |
6061 | return tr->percpu_dir; | |
b04cc6b1 | 6062 | |
7eeafbca | 6063 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 6064 | if (IS_ERR(d_tracer)) |
b04cc6b1 FW |
6065 | return NULL; |
6066 | ||
8434dc93 | 6067 | tr->percpu_dir = tracefs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 6068 | |
2b6080f2 | 6069 | WARN_ONCE(!tr->percpu_dir, |
8434dc93 | 6070 | "Could not create tracefs directory 'per_cpu/%d'\n", cpu); |
b04cc6b1 | 6071 | |
2b6080f2 | 6072 | return tr->percpu_dir; |
b04cc6b1 FW |
6073 | } |
6074 | ||
649e9c70 ON |
6075 | static struct dentry * |
6076 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
6077 | void *data, long cpu, const struct file_operations *fops) | |
6078 | { | |
6079 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
6080 | ||
6081 | if (ret) /* See tracing_get_cpu() */ | |
7682c918 | 6082 | d_inode(ret)->i_cdev = (void *)(cpu + 1); |
649e9c70 ON |
6083 | return ret; |
6084 | } | |
6085 | ||
2b6080f2 | 6086 | static void |
8434dc93 | 6087 | tracing_init_tracefs_percpu(struct trace_array *tr, long cpu) |
b04cc6b1 | 6088 | { |
2b6080f2 | 6089 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 6090 | struct dentry *d_cpu; |
dd49a38c | 6091 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 6092 | |
0a3d7ce7 NK |
6093 | if (!d_percpu) |
6094 | return; | |
6095 | ||
dd49a38c | 6096 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8434dc93 | 6097 | d_cpu = tracefs_create_dir(cpu_dir, d_percpu); |
8656e7a2 | 6098 | if (!d_cpu) { |
8434dc93 | 6099 | pr_warning("Could not create tracefs '%s' entry\n", cpu_dir); |
8656e7a2 FW |
6100 | return; |
6101 | } | |
b04cc6b1 | 6102 | |
8656e7a2 | 6103 | /* per cpu trace_pipe */ |
649e9c70 | 6104 | trace_create_cpu_file("trace_pipe", 0444, d_cpu, |
15544209 | 6105 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
6106 | |
6107 | /* per cpu trace */ | |
649e9c70 | 6108 | trace_create_cpu_file("trace", 0644, d_cpu, |
6484c71c | 6109 | tr, cpu, &tracing_fops); |
7f96f93f | 6110 | |
649e9c70 | 6111 | trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, |
46ef2be0 | 6112 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 6113 | |
649e9c70 | 6114 | trace_create_cpu_file("stats", 0444, d_cpu, |
4d3435b8 | 6115 | tr, cpu, &tracing_stats_fops); |
438ced17 | 6116 | |
649e9c70 | 6117 | trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, |
0bc392ee | 6118 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
6119 | |
6120 | #ifdef CONFIG_TRACER_SNAPSHOT | |
649e9c70 | 6121 | trace_create_cpu_file("snapshot", 0644, d_cpu, |
6484c71c | 6122 | tr, cpu, &snapshot_fops); |
6de58e62 | 6123 | |
649e9c70 | 6124 | trace_create_cpu_file("snapshot_raw", 0444, d_cpu, |
46ef2be0 | 6125 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 6126 | #endif |
b04cc6b1 FW |
6127 | } |
6128 | ||
60a11774 SR |
6129 | #ifdef CONFIG_FTRACE_SELFTEST |
6130 | /* Let selftest have access to static functions in this file */ | |
6131 | #include "trace_selftest.c" | |
6132 | #endif | |
6133 | ||
577b785f SR |
6134 | struct trace_option_dentry { |
6135 | struct tracer_opt *opt; | |
6136 | struct tracer_flags *flags; | |
2b6080f2 | 6137 | struct trace_array *tr; |
577b785f SR |
6138 | struct dentry *entry; |
6139 | }; | |
6140 | ||
6141 | static ssize_t | |
6142 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
6143 | loff_t *ppos) | |
6144 | { | |
6145 | struct trace_option_dentry *topt = filp->private_data; | |
6146 | char *buf; | |
6147 | ||
6148 | if (topt->flags->val & topt->opt->bit) | |
6149 | buf = "1\n"; | |
6150 | else | |
6151 | buf = "0\n"; | |
6152 | ||
6153 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
6154 | } | |
6155 | ||
6156 | static ssize_t | |
6157 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
6158 | loff_t *ppos) | |
6159 | { | |
6160 | struct trace_option_dentry *topt = filp->private_data; | |
6161 | unsigned long val; | |
577b785f SR |
6162 | int ret; |
6163 | ||
22fe9b54 PH |
6164 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
6165 | if (ret) | |
577b785f SR |
6166 | return ret; |
6167 | ||
8d18eaaf LZ |
6168 | if (val != 0 && val != 1) |
6169 | return -EINVAL; | |
577b785f | 6170 | |
8d18eaaf | 6171 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 6172 | mutex_lock(&trace_types_lock); |
8c1a49ae | 6173 | ret = __set_tracer_option(topt->tr, topt->flags, |
c757bea9 | 6174 | topt->opt, !val); |
577b785f SR |
6175 | mutex_unlock(&trace_types_lock); |
6176 | if (ret) | |
6177 | return ret; | |
577b785f SR |
6178 | } |
6179 | ||
6180 | *ppos += cnt; | |
6181 | ||
6182 | return cnt; | |
6183 | } | |
6184 | ||
6185 | ||
6186 | static const struct file_operations trace_options_fops = { | |
6187 | .open = tracing_open_generic, | |
6188 | .read = trace_options_read, | |
6189 | .write = trace_options_write, | |
b444786f | 6190 | .llseek = generic_file_llseek, |
577b785f SR |
6191 | }; |
6192 | ||
a8259075 SR |
6193 | static ssize_t |
6194 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
6195 | loff_t *ppos) | |
6196 | { | |
6197 | long index = (long)filp->private_data; | |
6198 | char *buf; | |
6199 | ||
6200 | if (trace_flags & (1 << index)) | |
6201 | buf = "1\n"; | |
6202 | else | |
6203 | buf = "0\n"; | |
6204 | ||
6205 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
6206 | } | |
6207 | ||
6208 | static ssize_t | |
6209 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
6210 | loff_t *ppos) | |
6211 | { | |
2b6080f2 | 6212 | struct trace_array *tr = &global_trace; |
a8259075 | 6213 | long index = (long)filp->private_data; |
a8259075 SR |
6214 | unsigned long val; |
6215 | int ret; | |
6216 | ||
22fe9b54 PH |
6217 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
6218 | if (ret) | |
a8259075 SR |
6219 | return ret; |
6220 | ||
f2d84b65 | 6221 | if (val != 0 && val != 1) |
a8259075 | 6222 | return -EINVAL; |
69d34da2 SRRH |
6223 | |
6224 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 6225 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 6226 | mutex_unlock(&trace_types_lock); |
a8259075 | 6227 | |
613f04a0 SRRH |
6228 | if (ret < 0) |
6229 | return ret; | |
6230 | ||
a8259075 SR |
6231 | *ppos += cnt; |
6232 | ||
6233 | return cnt; | |
6234 | } | |
6235 | ||
a8259075 SR |
6236 | static const struct file_operations trace_options_core_fops = { |
6237 | .open = tracing_open_generic, | |
6238 | .read = trace_options_core_read, | |
6239 | .write = trace_options_core_write, | |
b444786f | 6240 | .llseek = generic_file_llseek, |
a8259075 SR |
6241 | }; |
6242 | ||
5452af66 | 6243 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 6244 | umode_t mode, |
5452af66 FW |
6245 | struct dentry *parent, |
6246 | void *data, | |
6247 | const struct file_operations *fops) | |
6248 | { | |
6249 | struct dentry *ret; | |
6250 | ||
8434dc93 | 6251 | ret = tracefs_create_file(name, mode, parent, data, fops); |
5452af66 | 6252 | if (!ret) |
8434dc93 | 6253 | pr_warning("Could not create tracefs '%s' entry\n", name); |
5452af66 FW |
6254 | |
6255 | return ret; | |
6256 | } | |
6257 | ||
6258 | ||
2b6080f2 | 6259 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
6260 | { |
6261 | struct dentry *d_tracer; | |
a8259075 | 6262 | |
2b6080f2 SR |
6263 | if (tr->options) |
6264 | return tr->options; | |
a8259075 | 6265 | |
7eeafbca | 6266 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 6267 | if (IS_ERR(d_tracer)) |
a8259075 SR |
6268 | return NULL; |
6269 | ||
8434dc93 | 6270 | tr->options = tracefs_create_dir("options", d_tracer); |
2b6080f2 | 6271 | if (!tr->options) { |
8434dc93 | 6272 | pr_warning("Could not create tracefs directory 'options'\n"); |
a8259075 SR |
6273 | return NULL; |
6274 | } | |
6275 | ||
2b6080f2 | 6276 | return tr->options; |
a8259075 SR |
6277 | } |
6278 | ||
577b785f | 6279 | static void |
2b6080f2 SR |
6280 | create_trace_option_file(struct trace_array *tr, |
6281 | struct trace_option_dentry *topt, | |
577b785f SR |
6282 | struct tracer_flags *flags, |
6283 | struct tracer_opt *opt) | |
6284 | { | |
6285 | struct dentry *t_options; | |
577b785f | 6286 | |
2b6080f2 | 6287 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
6288 | if (!t_options) |
6289 | return; | |
6290 | ||
6291 | topt->flags = flags; | |
6292 | topt->opt = opt; | |
2b6080f2 | 6293 | topt->tr = tr; |
577b785f | 6294 | |
5452af66 | 6295 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
6296 | &trace_options_fops); |
6297 | ||
577b785f SR |
6298 | } |
6299 | ||
6300 | static struct trace_option_dentry * | |
2b6080f2 | 6301 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
6302 | { |
6303 | struct trace_option_dentry *topts; | |
6304 | struct tracer_flags *flags; | |
6305 | struct tracer_opt *opts; | |
6306 | int cnt; | |
6307 | ||
6308 | if (!tracer) | |
6309 | return NULL; | |
6310 | ||
6311 | flags = tracer->flags; | |
6312 | ||
6313 | if (!flags || !flags->opts) | |
6314 | return NULL; | |
6315 | ||
6316 | opts = flags->opts; | |
6317 | ||
6318 | for (cnt = 0; opts[cnt].name; cnt++) | |
6319 | ; | |
6320 | ||
0cfe8245 | 6321 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
6322 | if (!topts) |
6323 | return NULL; | |
6324 | ||
6325 | for (cnt = 0; opts[cnt].name; cnt++) | |
2b6080f2 | 6326 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f SR |
6327 | &opts[cnt]); |
6328 | ||
6329 | return topts; | |
6330 | } | |
6331 | ||
6332 | static void | |
6333 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
6334 | { | |
6335 | int cnt; | |
6336 | ||
6337 | if (!topts) | |
6338 | return; | |
6339 | ||
3f4d8f78 | 6340 | for (cnt = 0; topts[cnt].opt; cnt++) |
8434dc93 | 6341 | tracefs_remove(topts[cnt].entry); |
577b785f SR |
6342 | |
6343 | kfree(topts); | |
6344 | } | |
6345 | ||
a8259075 | 6346 | static struct dentry * |
2b6080f2 SR |
6347 | create_trace_option_core_file(struct trace_array *tr, |
6348 | const char *option, long index) | |
a8259075 SR |
6349 | { |
6350 | struct dentry *t_options; | |
a8259075 | 6351 | |
2b6080f2 | 6352 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
6353 | if (!t_options) |
6354 | return NULL; | |
6355 | ||
5452af66 | 6356 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 6357 | &trace_options_core_fops); |
a8259075 SR |
6358 | } |
6359 | ||
2b6080f2 | 6360 | static __init void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
6361 | { |
6362 | struct dentry *t_options; | |
a8259075 SR |
6363 | int i; |
6364 | ||
2b6080f2 | 6365 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
6366 | if (!t_options) |
6367 | return; | |
6368 | ||
5452af66 | 6369 | for (i = 0; trace_options[i]; i++) |
2b6080f2 | 6370 | create_trace_option_core_file(tr, trace_options[i], i); |
a8259075 SR |
6371 | } |
6372 | ||
499e5470 SR |
6373 | static ssize_t |
6374 | rb_simple_read(struct file *filp, char __user *ubuf, | |
6375 | size_t cnt, loff_t *ppos) | |
6376 | { | |
348f0fc2 | 6377 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
6378 | char buf[64]; |
6379 | int r; | |
6380 | ||
10246fa3 | 6381 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
6382 | r = sprintf(buf, "%d\n", r); |
6383 | ||
6384 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
6385 | } | |
6386 | ||
6387 | static ssize_t | |
6388 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
6389 | size_t cnt, loff_t *ppos) | |
6390 | { | |
348f0fc2 | 6391 | struct trace_array *tr = filp->private_data; |
12883efb | 6392 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
6393 | unsigned long val; |
6394 | int ret; | |
6395 | ||
6396 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
6397 | if (ret) | |
6398 | return ret; | |
6399 | ||
6400 | if (buffer) { | |
2df8f8a6 SR |
6401 | mutex_lock(&trace_types_lock); |
6402 | if (val) { | |
10246fa3 | 6403 | tracer_tracing_on(tr); |
2b6080f2 SR |
6404 | if (tr->current_trace->start) |
6405 | tr->current_trace->start(tr); | |
2df8f8a6 | 6406 | } else { |
10246fa3 | 6407 | tracer_tracing_off(tr); |
2b6080f2 SR |
6408 | if (tr->current_trace->stop) |
6409 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
6410 | } |
6411 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
6412 | } |
6413 | ||
6414 | (*ppos)++; | |
6415 | ||
6416 | return cnt; | |
6417 | } | |
6418 | ||
6419 | static const struct file_operations rb_simple_fops = { | |
7b85af63 | 6420 | .open = tracing_open_generic_tr, |
499e5470 SR |
6421 | .read = rb_simple_read, |
6422 | .write = rb_simple_write, | |
7b85af63 | 6423 | .release = tracing_release_generic_tr, |
499e5470 SR |
6424 | .llseek = default_llseek, |
6425 | }; | |
6426 | ||
277ba044 SR |
6427 | struct dentry *trace_instance_dir; |
6428 | ||
6429 | static void | |
8434dc93 | 6430 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer); |
277ba044 | 6431 | |
55034cd6 SRRH |
6432 | static int |
6433 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
6434 | { |
6435 | enum ring_buffer_flags rb_flags; | |
737223fb SRRH |
6436 | |
6437 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; | |
6438 | ||
dced341b SRRH |
6439 | buf->tr = tr; |
6440 | ||
55034cd6 SRRH |
6441 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
6442 | if (!buf->buffer) | |
6443 | return -ENOMEM; | |
737223fb | 6444 | |
55034cd6 SRRH |
6445 | buf->data = alloc_percpu(struct trace_array_cpu); |
6446 | if (!buf->data) { | |
6447 | ring_buffer_free(buf->buffer); | |
6448 | return -ENOMEM; | |
6449 | } | |
737223fb | 6450 | |
737223fb SRRH |
6451 | /* Allocate the first page for all buffers */ |
6452 | set_buffer_entries(&tr->trace_buffer, | |
6453 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
6454 | ||
55034cd6 SRRH |
6455 | return 0; |
6456 | } | |
737223fb | 6457 | |
55034cd6 SRRH |
6458 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
6459 | { | |
6460 | int ret; | |
737223fb | 6461 | |
55034cd6 SRRH |
6462 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
6463 | if (ret) | |
6464 | return ret; | |
737223fb | 6465 | |
55034cd6 SRRH |
6466 | #ifdef CONFIG_TRACER_MAX_TRACE |
6467 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
6468 | allocate_snapshot ? size : 1); | |
6469 | if (WARN_ON(ret)) { | |
737223fb | 6470 | ring_buffer_free(tr->trace_buffer.buffer); |
55034cd6 SRRH |
6471 | free_percpu(tr->trace_buffer.data); |
6472 | return -ENOMEM; | |
6473 | } | |
6474 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 6475 | |
55034cd6 SRRH |
6476 | /* |
6477 | * Only the top level trace array gets its snapshot allocated | |
6478 | * from the kernel command line. | |
6479 | */ | |
6480 | allocate_snapshot = false; | |
737223fb | 6481 | #endif |
55034cd6 | 6482 | return 0; |
737223fb SRRH |
6483 | } |
6484 | ||
f0b70cc4 SRRH |
6485 | static void free_trace_buffer(struct trace_buffer *buf) |
6486 | { | |
6487 | if (buf->buffer) { | |
6488 | ring_buffer_free(buf->buffer); | |
6489 | buf->buffer = NULL; | |
6490 | free_percpu(buf->data); | |
6491 | buf->data = NULL; | |
6492 | } | |
6493 | } | |
6494 | ||
23aaa3c1 SRRH |
6495 | static void free_trace_buffers(struct trace_array *tr) |
6496 | { | |
6497 | if (!tr) | |
6498 | return; | |
6499 | ||
f0b70cc4 | 6500 | free_trace_buffer(&tr->trace_buffer); |
23aaa3c1 SRRH |
6501 | |
6502 | #ifdef CONFIG_TRACER_MAX_TRACE | |
f0b70cc4 | 6503 | free_trace_buffer(&tr->max_buffer); |
23aaa3c1 SRRH |
6504 | #endif |
6505 | } | |
6506 | ||
eae47358 | 6507 | static int instance_mkdir(const char *name) |
737223fb | 6508 | { |
277ba044 SR |
6509 | struct trace_array *tr; |
6510 | int ret; | |
277ba044 SR |
6511 | |
6512 | mutex_lock(&trace_types_lock); | |
6513 | ||
6514 | ret = -EEXIST; | |
6515 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6516 | if (tr->name && strcmp(tr->name, name) == 0) | |
6517 | goto out_unlock; | |
6518 | } | |
6519 | ||
6520 | ret = -ENOMEM; | |
6521 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
6522 | if (!tr) | |
6523 | goto out_unlock; | |
6524 | ||
6525 | tr->name = kstrdup(name, GFP_KERNEL); | |
6526 | if (!tr->name) | |
6527 | goto out_free_tr; | |
6528 | ||
ccfe9e42 AL |
6529 | if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) |
6530 | goto out_free_tr; | |
6531 | ||
6532 | cpumask_copy(tr->tracing_cpumask, cpu_all_mask); | |
6533 | ||
277ba044 SR |
6534 | raw_spin_lock_init(&tr->start_lock); |
6535 | ||
0b9b12c1 SRRH |
6536 | tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
6537 | ||
277ba044 SR |
6538 | tr->current_trace = &nop_trace; |
6539 | ||
6540 | INIT_LIST_HEAD(&tr->systems); | |
6541 | INIT_LIST_HEAD(&tr->events); | |
6542 | ||
737223fb | 6543 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
6544 | goto out_free_tr; |
6545 | ||
8434dc93 | 6546 | tr->dir = tracefs_create_dir(name, trace_instance_dir); |
277ba044 SR |
6547 | if (!tr->dir) |
6548 | goto out_free_tr; | |
6549 | ||
6550 | ret = event_trace_add_tracer(tr->dir, tr); | |
609e85a7 | 6551 | if (ret) { |
8434dc93 | 6552 | tracefs_remove_recursive(tr->dir); |
277ba044 | 6553 | goto out_free_tr; |
609e85a7 | 6554 | } |
277ba044 | 6555 | |
8434dc93 | 6556 | init_tracer_tracefs(tr, tr->dir); |
277ba044 SR |
6557 | |
6558 | list_add(&tr->list, &ftrace_trace_arrays); | |
6559 | ||
6560 | mutex_unlock(&trace_types_lock); | |
6561 | ||
6562 | return 0; | |
6563 | ||
6564 | out_free_tr: | |
23aaa3c1 | 6565 | free_trace_buffers(tr); |
ccfe9e42 | 6566 | free_cpumask_var(tr->tracing_cpumask); |
277ba044 SR |
6567 | kfree(tr->name); |
6568 | kfree(tr); | |
6569 | ||
6570 | out_unlock: | |
6571 | mutex_unlock(&trace_types_lock); | |
6572 | ||
6573 | return ret; | |
6574 | ||
6575 | } | |
6576 | ||
eae47358 | 6577 | static int instance_rmdir(const char *name) |
0c8916c3 SR |
6578 | { |
6579 | struct trace_array *tr; | |
6580 | int found = 0; | |
6581 | int ret; | |
6582 | ||
6583 | mutex_lock(&trace_types_lock); | |
6584 | ||
6585 | ret = -ENODEV; | |
6586 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
6587 | if (tr->name && strcmp(tr->name, name) == 0) { | |
6588 | found = 1; | |
6589 | break; | |
6590 | } | |
6591 | } | |
6592 | if (!found) | |
6593 | goto out_unlock; | |
6594 | ||
a695cb58 | 6595 | ret = -EBUSY; |
cf6ab6d9 | 6596 | if (tr->ref || (tr->current_trace && tr->current_trace->ref)) |
a695cb58 SRRH |
6597 | goto out_unlock; |
6598 | ||
0c8916c3 SR |
6599 | list_del(&tr->list); |
6600 | ||
6b450d25 | 6601 | tracing_set_nop(tr); |
0c8916c3 | 6602 | event_trace_del_tracer(tr); |
591dffda | 6603 | ftrace_destroy_function_files(tr); |
0c8916c3 | 6604 | debugfs_remove_recursive(tr->dir); |
a9fcaaac | 6605 | free_trace_buffers(tr); |
0c8916c3 SR |
6606 | |
6607 | kfree(tr->name); | |
6608 | kfree(tr); | |
6609 | ||
6610 | ret = 0; | |
6611 | ||
6612 | out_unlock: | |
6613 | mutex_unlock(&trace_types_lock); | |
6614 | ||
6615 | return ret; | |
6616 | } | |
6617 | ||
277ba044 SR |
6618 | static __init void create_trace_instances(struct dentry *d_tracer) |
6619 | { | |
eae47358 SRRH |
6620 | trace_instance_dir = tracefs_create_instance_dir("instances", d_tracer, |
6621 | instance_mkdir, | |
6622 | instance_rmdir); | |
277ba044 SR |
6623 | if (WARN_ON(!trace_instance_dir)) |
6624 | return; | |
277ba044 SR |
6625 | } |
6626 | ||
2b6080f2 | 6627 | static void |
8434dc93 | 6628 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
2b6080f2 | 6629 | { |
121aaee7 | 6630 | int cpu; |
2b6080f2 | 6631 | |
607e2ea1 SRRH |
6632 | trace_create_file("available_tracers", 0444, d_tracer, |
6633 | tr, &show_traces_fops); | |
6634 | ||
6635 | trace_create_file("current_tracer", 0644, d_tracer, | |
6636 | tr, &set_tracer_fops); | |
6637 | ||
ccfe9e42 AL |
6638 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
6639 | tr, &tracing_cpumask_fops); | |
6640 | ||
2b6080f2 SR |
6641 | trace_create_file("trace_options", 0644, d_tracer, |
6642 | tr, &tracing_iter_fops); | |
6643 | ||
6644 | trace_create_file("trace", 0644, d_tracer, | |
6484c71c | 6645 | tr, &tracing_fops); |
2b6080f2 SR |
6646 | |
6647 | trace_create_file("trace_pipe", 0444, d_tracer, | |
15544209 | 6648 | tr, &tracing_pipe_fops); |
2b6080f2 SR |
6649 | |
6650 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
0bc392ee | 6651 | tr, &tracing_entries_fops); |
2b6080f2 SR |
6652 | |
6653 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
6654 | tr, &tracing_total_entries_fops); | |
6655 | ||
238ae93d | 6656 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
6657 | tr, &tracing_free_buffer_fops); |
6658 | ||
6659 | trace_create_file("trace_marker", 0220, d_tracer, | |
6660 | tr, &tracing_mark_fops); | |
6661 | ||
6662 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
6663 | &trace_clock_fops); | |
6664 | ||
6665 | trace_create_file("tracing_on", 0644, d_tracer, | |
6484c71c | 6666 | tr, &rb_simple_fops); |
ce9bae55 | 6667 | |
6d9b3fa5 SRRH |
6668 | #ifdef CONFIG_TRACER_MAX_TRACE |
6669 | trace_create_file("tracing_max_latency", 0644, d_tracer, | |
6670 | &tr->max_latency, &tracing_max_lat_fops); | |
6671 | #endif | |
6672 | ||
591dffda SRRH |
6673 | if (ftrace_create_function_files(tr, d_tracer)) |
6674 | WARN(1, "Could not allocate function filter files"); | |
6675 | ||
ce9bae55 SRRH |
6676 | #ifdef CONFIG_TRACER_SNAPSHOT |
6677 | trace_create_file("snapshot", 0644, d_tracer, | |
6484c71c | 6678 | tr, &snapshot_fops); |
ce9bae55 | 6679 | #endif |
121aaee7 SRRH |
6680 | |
6681 | for_each_tracing_cpu(cpu) | |
8434dc93 | 6682 | tracing_init_tracefs_percpu(tr, cpu); |
121aaee7 | 6683 | |
2b6080f2 SR |
6684 | } |
6685 | ||
f76180bc SRRH |
6686 | static struct vfsmount *trace_automount(void *ingore) |
6687 | { | |
6688 | struct vfsmount *mnt; | |
6689 | struct file_system_type *type; | |
6690 | ||
6691 | /* | |
6692 | * To maintain backward compatibility for tools that mount | |
6693 | * debugfs to get to the tracing facility, tracefs is automatically | |
6694 | * mounted to the debugfs/tracing directory. | |
6695 | */ | |
6696 | type = get_fs_type("tracefs"); | |
6697 | if (!type) | |
6698 | return NULL; | |
6699 | mnt = vfs_kern_mount(type, 0, "tracefs", NULL); | |
6700 | put_filesystem(type); | |
6701 | if (IS_ERR(mnt)) | |
6702 | return NULL; | |
6703 | mntget(mnt); | |
6704 | ||
6705 | return mnt; | |
6706 | } | |
6707 | ||
7eeafbca SRRH |
6708 | /** |
6709 | * tracing_init_dentry - initialize top level trace array | |
6710 | * | |
6711 | * This is called when creating files or directories in the tracing | |
6712 | * directory. It is called via fs_initcall() by any of the boot up code | |
6713 | * and expects to return the dentry of the top level tracing directory. | |
6714 | */ | |
6715 | struct dentry *tracing_init_dentry(void) | |
6716 | { | |
6717 | struct trace_array *tr = &global_trace; | |
6718 | ||
f76180bc | 6719 | /* The top level trace array uses NULL as parent */ |
7eeafbca | 6720 | if (tr->dir) |
f76180bc | 6721 | return NULL; |
7eeafbca SRRH |
6722 | |
6723 | if (WARN_ON(!debugfs_initialized())) | |
6724 | return ERR_PTR(-ENODEV); | |
6725 | ||
f76180bc SRRH |
6726 | /* |
6727 | * As there may still be users that expect the tracing | |
6728 | * files to exist in debugfs/tracing, we must automount | |
6729 | * the tracefs file system there, so older tools still | |
6730 | * work with the newer kerenl. | |
6731 | */ | |
6732 | tr->dir = debugfs_create_automount("tracing", NULL, | |
6733 | trace_automount, NULL); | |
7eeafbca SRRH |
6734 | if (!tr->dir) { |
6735 | pr_warn_once("Could not create debugfs directory 'tracing'\n"); | |
6736 | return ERR_PTR(-ENOMEM); | |
6737 | } | |
6738 | ||
8434dc93 | 6739 | return NULL; |
7eeafbca SRRH |
6740 | } |
6741 | ||
0c564a53 SRRH |
6742 | extern struct trace_enum_map *__start_ftrace_enum_maps[]; |
6743 | extern struct trace_enum_map *__stop_ftrace_enum_maps[]; | |
6744 | ||
6745 | static void __init trace_enum_init(void) | |
6746 | { | |
3673b8e4 SRRH |
6747 | int len; |
6748 | ||
6749 | len = __stop_ftrace_enum_maps - __start_ftrace_enum_maps; | |
9828413d | 6750 | trace_insert_enum_map(NULL, __start_ftrace_enum_maps, len); |
3673b8e4 SRRH |
6751 | } |
6752 | ||
6753 | #ifdef CONFIG_MODULES | |
6754 | static void trace_module_add_enums(struct module *mod) | |
6755 | { | |
6756 | if (!mod->num_trace_enums) | |
6757 | return; | |
6758 | ||
6759 | /* | |
6760 | * Modules with bad taint do not have events created, do | |
6761 | * not bother with enums either. | |
6762 | */ | |
6763 | if (trace_module_has_bad_taint(mod)) | |
6764 | return; | |
6765 | ||
9828413d | 6766 | trace_insert_enum_map(mod, mod->trace_enums, mod->num_trace_enums); |
3673b8e4 SRRH |
6767 | } |
6768 | ||
9828413d SRRH |
6769 | #ifdef CONFIG_TRACE_ENUM_MAP_FILE |
6770 | static void trace_module_remove_enums(struct module *mod) | |
6771 | { | |
6772 | union trace_enum_map_item *map; | |
6773 | union trace_enum_map_item **last = &trace_enum_maps; | |
6774 | ||
6775 | if (!mod->num_trace_enums) | |
6776 | return; | |
6777 | ||
6778 | mutex_lock(&trace_enum_mutex); | |
6779 | ||
6780 | map = trace_enum_maps; | |
6781 | ||
6782 | while (map) { | |
6783 | if (map->head.mod == mod) | |
6784 | break; | |
6785 | map = trace_enum_jmp_to_tail(map); | |
6786 | last = &map->tail.next; | |
6787 | map = map->tail.next; | |
6788 | } | |
6789 | if (!map) | |
6790 | goto out; | |
6791 | ||
6792 | *last = trace_enum_jmp_to_tail(map)->tail.next; | |
6793 | kfree(map); | |
6794 | out: | |
6795 | mutex_unlock(&trace_enum_mutex); | |
6796 | } | |
6797 | #else | |
6798 | static inline void trace_module_remove_enums(struct module *mod) { } | |
6799 | #endif /* CONFIG_TRACE_ENUM_MAP_FILE */ | |
6800 | ||
3673b8e4 SRRH |
6801 | static int trace_module_notify(struct notifier_block *self, |
6802 | unsigned long val, void *data) | |
6803 | { | |
6804 | struct module *mod = data; | |
6805 | ||
6806 | switch (val) { | |
6807 | case MODULE_STATE_COMING: | |
6808 | trace_module_add_enums(mod); | |
6809 | break; | |
9828413d SRRH |
6810 | case MODULE_STATE_GOING: |
6811 | trace_module_remove_enums(mod); | |
6812 | break; | |
3673b8e4 SRRH |
6813 | } |
6814 | ||
6815 | return 0; | |
0c564a53 SRRH |
6816 | } |
6817 | ||
3673b8e4 SRRH |
6818 | static struct notifier_block trace_module_nb = { |
6819 | .notifier_call = trace_module_notify, | |
6820 | .priority = 0, | |
6821 | }; | |
9828413d | 6822 | #endif /* CONFIG_MODULES */ |
3673b8e4 | 6823 | |
8434dc93 | 6824 | static __init int tracer_init_tracefs(void) |
bc0c38d1 SR |
6825 | { |
6826 | struct dentry *d_tracer; | |
bc0c38d1 | 6827 | |
7e53bd42 LJ |
6828 | trace_access_lock_init(); |
6829 | ||
bc0c38d1 | 6830 | d_tracer = tracing_init_dentry(); |
14a5ae40 | 6831 | if (IS_ERR(d_tracer)) |
ed6f1c99 | 6832 | return 0; |
bc0c38d1 | 6833 | |
8434dc93 | 6834 | init_tracer_tracefs(&global_trace, d_tracer); |
bc0c38d1 | 6835 | |
5452af66 | 6836 | trace_create_file("tracing_thresh", 0644, d_tracer, |
6508fa76 | 6837 | &global_trace, &tracing_thresh_fops); |
a8259075 | 6838 | |
339ae5d3 | 6839 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
6840 | NULL, &tracing_readme_fops); |
6841 | ||
69abe6a5 AP |
6842 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
6843 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 6844 | |
939c7a4f YY |
6845 | trace_create_file("saved_cmdlines_size", 0644, d_tracer, |
6846 | NULL, &tracing_saved_cmdlines_size_fops); | |
6847 | ||
0c564a53 SRRH |
6848 | trace_enum_init(); |
6849 | ||
9828413d SRRH |
6850 | trace_create_enum_file(d_tracer); |
6851 | ||
3673b8e4 SRRH |
6852 | #ifdef CONFIG_MODULES |
6853 | register_module_notifier(&trace_module_nb); | |
6854 | #endif | |
6855 | ||
bc0c38d1 | 6856 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
6857 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
6858 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 6859 | #endif |
b04cc6b1 | 6860 | |
277ba044 | 6861 | create_trace_instances(d_tracer); |
5452af66 | 6862 | |
2b6080f2 | 6863 | create_trace_options_dir(&global_trace); |
b04cc6b1 | 6864 | |
09d23a1d SRRH |
6865 | /* If the tracer was started via cmdline, create options for it here */ |
6866 | if (global_trace.current_trace != &nop_trace) | |
6867 | update_tracer_options(&global_trace, global_trace.current_trace); | |
6868 | ||
b5ad384e | 6869 | return 0; |
bc0c38d1 SR |
6870 | } |
6871 | ||
3f5a54e3 SR |
6872 | static int trace_panic_handler(struct notifier_block *this, |
6873 | unsigned long event, void *unused) | |
6874 | { | |
944ac425 | 6875 | if (ftrace_dump_on_oops) |
cecbca96 | 6876 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6877 | return NOTIFY_OK; |
6878 | } | |
6879 | ||
6880 | static struct notifier_block trace_panic_notifier = { | |
6881 | .notifier_call = trace_panic_handler, | |
6882 | .next = NULL, | |
6883 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
6884 | }; | |
6885 | ||
6886 | static int trace_die_handler(struct notifier_block *self, | |
6887 | unsigned long val, | |
6888 | void *data) | |
6889 | { | |
6890 | switch (val) { | |
6891 | case DIE_OOPS: | |
944ac425 | 6892 | if (ftrace_dump_on_oops) |
cecbca96 | 6893 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
6894 | break; |
6895 | default: | |
6896 | break; | |
6897 | } | |
6898 | return NOTIFY_OK; | |
6899 | } | |
6900 | ||
6901 | static struct notifier_block trace_die_notifier = { | |
6902 | .notifier_call = trace_die_handler, | |
6903 | .priority = 200 | |
6904 | }; | |
6905 | ||
6906 | /* | |
6907 | * printk is set to max of 1024, we really don't need it that big. | |
6908 | * Nothing should be printing 1000 characters anyway. | |
6909 | */ | |
6910 | #define TRACE_MAX_PRINT 1000 | |
6911 | ||
6912 | /* | |
6913 | * Define here KERN_TRACE so that we have one place to modify | |
6914 | * it if we decide to change what log level the ftrace dump | |
6915 | * should be at. | |
6916 | */ | |
428aee14 | 6917 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 6918 | |
955b61e5 | 6919 | void |
3f5a54e3 SR |
6920 | trace_printk_seq(struct trace_seq *s) |
6921 | { | |
6922 | /* Probably should print a warning here. */ | |
3a161d99 SRRH |
6923 | if (s->seq.len >= TRACE_MAX_PRINT) |
6924 | s->seq.len = TRACE_MAX_PRINT; | |
3f5a54e3 | 6925 | |
820b75f6 SRRH |
6926 | /* |
6927 | * More paranoid code. Although the buffer size is set to | |
6928 | * PAGE_SIZE, and TRACE_MAX_PRINT is 1000, this is just | |
6929 | * an extra layer of protection. | |
6930 | */ | |
6931 | if (WARN_ON_ONCE(s->seq.len >= s->seq.size)) | |
6932 | s->seq.len = s->seq.size - 1; | |
3f5a54e3 SR |
6933 | |
6934 | /* should be zero ended, but we are paranoid. */ | |
3a161d99 | 6935 | s->buffer[s->seq.len] = 0; |
3f5a54e3 SR |
6936 | |
6937 | printk(KERN_TRACE "%s", s->buffer); | |
6938 | ||
f9520750 | 6939 | trace_seq_init(s); |
3f5a54e3 SR |
6940 | } |
6941 | ||
955b61e5 JW |
6942 | void trace_init_global_iter(struct trace_iterator *iter) |
6943 | { | |
6944 | iter->tr = &global_trace; | |
2b6080f2 | 6945 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 6946 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 6947 | iter->trace_buffer = &global_trace.trace_buffer; |
b2f974d6 CS |
6948 | |
6949 | if (iter->trace && iter->trace->open) | |
6950 | iter->trace->open(iter); | |
6951 | ||
6952 | /* Annotate start of buffers if we had overruns */ | |
6953 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) | |
6954 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
6955 | ||
6956 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ | |
6957 | if (trace_clocks[iter->tr->clock_id].in_ns) | |
6958 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
955b61e5 JW |
6959 | } |
6960 | ||
7fe70b57 | 6961 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 6962 | { |
3f5a54e3 SR |
6963 | /* use static because iter can be a bit big for the stack */ |
6964 | static struct trace_iterator iter; | |
7fe70b57 | 6965 | static atomic_t dump_running; |
cf586b61 | 6966 | unsigned int old_userobj; |
d769041f SR |
6967 | unsigned long flags; |
6968 | int cnt = 0, cpu; | |
3f5a54e3 | 6969 | |
7fe70b57 SRRH |
6970 | /* Only allow one dump user at a time. */ |
6971 | if (atomic_inc_return(&dump_running) != 1) { | |
6972 | atomic_dec(&dump_running); | |
6973 | return; | |
6974 | } | |
3f5a54e3 | 6975 | |
7fe70b57 SRRH |
6976 | /* |
6977 | * Always turn off tracing when we dump. | |
6978 | * We don't need to show trace output of what happens | |
6979 | * between multiple crashes. | |
6980 | * | |
6981 | * If the user does a sysrq-z, then they can re-enable | |
6982 | * tracing with echo 1 > tracing_on. | |
6983 | */ | |
0ee6b6cf | 6984 | tracing_off(); |
cf586b61 | 6985 | |
7fe70b57 | 6986 | local_irq_save(flags); |
3f5a54e3 | 6987 | |
38dbe0b1 | 6988 | /* Simulate the iterator */ |
955b61e5 JW |
6989 | trace_init_global_iter(&iter); |
6990 | ||
d769041f | 6991 | for_each_tracing_cpu(cpu) { |
12883efb | 6992 | atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled); |
d769041f SR |
6993 | } |
6994 | ||
cf586b61 FW |
6995 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
6996 | ||
b54d3de9 TE |
6997 | /* don't look at user memory in panic mode */ |
6998 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
6999 | ||
cecbca96 FW |
7000 | switch (oops_dump_mode) { |
7001 | case DUMP_ALL: | |
ae3b5093 | 7002 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
7003 | break; |
7004 | case DUMP_ORIG: | |
7005 | iter.cpu_file = raw_smp_processor_id(); | |
7006 | break; | |
7007 | case DUMP_NONE: | |
7008 | goto out_enable; | |
7009 | default: | |
7010 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 7011 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
7012 | } |
7013 | ||
7014 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 7015 | |
7fe70b57 SRRH |
7016 | /* Did function tracer already get disabled? */ |
7017 | if (ftrace_is_dead()) { | |
7018 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
7019 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
7020 | } | |
7021 | ||
3f5a54e3 SR |
7022 | /* |
7023 | * We need to stop all tracing on all CPUS to read the | |
7024 | * the next buffer. This is a bit expensive, but is | |
7025 | * not done often. We fill all what we can read, | |
7026 | * and then release the locks again. | |
7027 | */ | |
7028 | ||
3f5a54e3 SR |
7029 | while (!trace_empty(&iter)) { |
7030 | ||
7031 | if (!cnt) | |
7032 | printk(KERN_TRACE "---------------------------------\n"); | |
7033 | ||
7034 | cnt++; | |
7035 | ||
7036 | /* reset all but tr, trace, and overruns */ | |
7037 | memset(&iter.seq, 0, | |
7038 | sizeof(struct trace_iterator) - | |
7039 | offsetof(struct trace_iterator, seq)); | |
7040 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
7041 | iter.pos = -1; | |
7042 | ||
955b61e5 | 7043 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
7044 | int ret; |
7045 | ||
7046 | ret = print_trace_line(&iter); | |
7047 | if (ret != TRACE_TYPE_NO_CONSUME) | |
7048 | trace_consume(&iter); | |
3f5a54e3 | 7049 | } |
b892e5c8 | 7050 | touch_nmi_watchdog(); |
3f5a54e3 SR |
7051 | |
7052 | trace_printk_seq(&iter.seq); | |
7053 | } | |
7054 | ||
7055 | if (!cnt) | |
7056 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
7057 | else | |
7058 | printk(KERN_TRACE "---------------------------------\n"); | |
7059 | ||
cecbca96 | 7060 | out_enable: |
7fe70b57 | 7061 | trace_flags |= old_userobj; |
cf586b61 | 7062 | |
7fe70b57 SRRH |
7063 | for_each_tracing_cpu(cpu) { |
7064 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); | |
cf586b61 | 7065 | } |
7fe70b57 | 7066 | atomic_dec(&dump_running); |
cd891ae0 | 7067 | local_irq_restore(flags); |
3f5a54e3 | 7068 | } |
a8eecf22 | 7069 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 7070 | |
3928a8a2 | 7071 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 7072 | { |
73c5162a | 7073 | int ring_buf_size; |
9e01c1b7 | 7074 | int ret = -ENOMEM; |
4c11d7ae | 7075 | |
9e01c1b7 RR |
7076 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
7077 | goto out; | |
7078 | ||
ccfe9e42 | 7079 | if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) |
9e01c1b7 | 7080 | goto out_free_buffer_mask; |
4c11d7ae | 7081 | |
07d777fe SR |
7082 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
7083 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 7084 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
7085 | trace_printk_init_buffers(); |
7086 | ||
73c5162a SR |
7087 | /* To save memory, keep the ring buffer size to its minimum */ |
7088 | if (ring_buffer_expanded) | |
7089 | ring_buf_size = trace_buf_size; | |
7090 | else | |
7091 | ring_buf_size = 1; | |
7092 | ||
9e01c1b7 | 7093 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
ccfe9e42 | 7094 | cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); |
9e01c1b7 | 7095 | |
2b6080f2 SR |
7096 | raw_spin_lock_init(&global_trace.start_lock); |
7097 | ||
2c4a33ab SRRH |
7098 | /* Used for event triggers */ |
7099 | temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); | |
7100 | if (!temp_buffer) | |
7101 | goto out_free_cpumask; | |
7102 | ||
939c7a4f YY |
7103 | if (trace_create_savedcmd() < 0) |
7104 | goto out_free_temp_buffer; | |
7105 | ||
9e01c1b7 | 7106 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 7107 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
7108 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
7109 | WARN_ON(1); | |
939c7a4f | 7110 | goto out_free_savedcmd; |
4c11d7ae | 7111 | } |
a7603ff4 | 7112 | |
499e5470 SR |
7113 | if (global_trace.buffer_disabled) |
7114 | tracing_off(); | |
4c11d7ae | 7115 | |
e1e232ca SR |
7116 | if (trace_boot_clock) { |
7117 | ret = tracing_set_clock(&global_trace, trace_boot_clock); | |
7118 | if (ret < 0) | |
7119 | pr_warning("Trace clock %s not defined, going back to default\n", | |
7120 | trace_boot_clock); | |
7121 | } | |
7122 | ||
ca164318 SRRH |
7123 | /* |
7124 | * register_tracer() might reference current_trace, so it | |
7125 | * needs to be set before we register anything. This is | |
7126 | * just a bootstrap of current_trace anyway. | |
7127 | */ | |
2b6080f2 SR |
7128 | global_trace.current_trace = &nop_trace; |
7129 | ||
0b9b12c1 SRRH |
7130 | global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
7131 | ||
4104d326 SRRH |
7132 | ftrace_init_global_array_ops(&global_trace); |
7133 | ||
ca164318 SRRH |
7134 | register_tracer(&nop_trace); |
7135 | ||
60a11774 SR |
7136 | /* All seems OK, enable tracing */ |
7137 | tracing_disabled = 0; | |
3928a8a2 | 7138 | |
3f5a54e3 SR |
7139 | atomic_notifier_chain_register(&panic_notifier_list, |
7140 | &trace_panic_notifier); | |
7141 | ||
7142 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 7143 | |
ae63b31e SR |
7144 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
7145 | ||
7146 | INIT_LIST_HEAD(&global_trace.systems); | |
7147 | INIT_LIST_HEAD(&global_trace.events); | |
7148 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
7149 | ||
7bcfaf54 SR |
7150 | while (trace_boot_options) { |
7151 | char *option; | |
7152 | ||
7153 | option = strsep(&trace_boot_options, ","); | |
2b6080f2 | 7154 | trace_set_options(&global_trace, option); |
7bcfaf54 SR |
7155 | } |
7156 | ||
77fd5c15 SRRH |
7157 | register_snapshot_cmd(); |
7158 | ||
2fc1dfbe | 7159 | return 0; |
3f5a54e3 | 7160 | |
939c7a4f YY |
7161 | out_free_savedcmd: |
7162 | free_saved_cmdlines_buffer(savedcmd); | |
2c4a33ab SRRH |
7163 | out_free_temp_buffer: |
7164 | ring_buffer_free(temp_buffer); | |
9e01c1b7 | 7165 | out_free_cpumask: |
ccfe9e42 | 7166 | free_cpumask_var(global_trace.tracing_cpumask); |
9e01c1b7 RR |
7167 | out_free_buffer_mask: |
7168 | free_cpumask_var(tracing_buffer_mask); | |
7169 | out: | |
7170 | return ret; | |
bc0c38d1 | 7171 | } |
b2821ae6 | 7172 | |
5f893b26 SRRH |
7173 | void __init trace_init(void) |
7174 | { | |
0daa2302 SRRH |
7175 | if (tracepoint_printk) { |
7176 | tracepoint_print_iter = | |
7177 | kmalloc(sizeof(*tracepoint_print_iter), GFP_KERNEL); | |
7178 | if (WARN_ON(!tracepoint_print_iter)) | |
7179 | tracepoint_printk = 0; | |
7180 | } | |
5f893b26 | 7181 | tracer_alloc_buffers(); |
0c564a53 | 7182 | trace_event_init(); |
5f893b26 SRRH |
7183 | } |
7184 | ||
b2821ae6 SR |
7185 | __init static int clear_boot_tracer(void) |
7186 | { | |
7187 | /* | |
7188 | * The default tracer at boot buffer is an init section. | |
7189 | * This function is called in lateinit. If we did not | |
7190 | * find the boot tracer, then clear it out, to prevent | |
7191 | * later registration from accessing the buffer that is | |
7192 | * about to be freed. | |
7193 | */ | |
7194 | if (!default_bootup_tracer) | |
7195 | return 0; | |
7196 | ||
7197 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
7198 | default_bootup_tracer); | |
7199 | default_bootup_tracer = NULL; | |
7200 | ||
7201 | return 0; | |
7202 | } | |
7203 | ||
8434dc93 | 7204 | fs_initcall(tracer_init_tracefs); |
b2821ae6 | 7205 | late_initcall(clear_boot_tracer); |