Commit | Line | Data |
---|---|---|
bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
273b281f | 15 | #include <generated/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
4c11d7ae | 23 | #include <linux/pagemap.h> |
bc0c38d1 SR |
24 | #include <linux/hardirq.h> |
25 | #include <linux/linkage.h> | |
26 | #include <linux/uaccess.h> | |
2cadf913 | 27 | #include <linux/kprobes.h> |
bc0c38d1 SR |
28 | #include <linux/ftrace.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/percpu.h> | |
2cadf913 | 31 | #include <linux/splice.h> |
3f5a54e3 | 32 | #include <linux/kdebug.h> |
5f0c6c03 | 33 | #include <linux/string.h> |
7e53bd42 | 34 | #include <linux/rwsem.h> |
5a0e3ad6 | 35 | #include <linux/slab.h> |
bc0c38d1 SR |
36 | #include <linux/ctype.h> |
37 | #include <linux/init.h> | |
2a2cc8f7 | 38 | #include <linux/poll.h> |
bc0c38d1 | 39 | #include <linux/fs.h> |
86387f7e | 40 | |
bc0c38d1 | 41 | #include "trace.h" |
f0868d1e | 42 | #include "trace_output.h" |
bc0c38d1 | 43 | |
73c5162a SR |
44 | /* |
45 | * On boot up, the ring buffer is set to the minimum size, so that | |
46 | * we do not waste memory on systems that are not using tracing. | |
47 | */ | |
020e5f85 | 48 | int ring_buffer_expanded; |
73c5162a | 49 | |
8e1b82e0 FW |
50 | /* |
51 | * We need to change this state when a selftest is running. | |
ff32504f FW |
52 | * A selftest will lurk into the ring-buffer to count the |
53 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 54 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
55 | * at the same time, giving false positive or negative results. |
56 | */ | |
8e1b82e0 | 57 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 58 | |
b2821ae6 SR |
59 | /* |
60 | * If a tracer is running, we do not want to run SELFTEST. | |
61 | */ | |
020e5f85 | 62 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 63 | |
adf9f195 FW |
64 | /* For tracers that don't implement custom flags */ |
65 | static struct tracer_opt dummy_tracer_opt[] = { | |
66 | { } | |
67 | }; | |
68 | ||
69 | static struct tracer_flags dummy_tracer_flags = { | |
70 | .val = 0, | |
71 | .opts = dummy_tracer_opt | |
72 | }; | |
73 | ||
74 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
75 | { | |
76 | return 0; | |
77 | } | |
0f048701 SR |
78 | |
79 | /* | |
80 | * Kill all tracing for good (never come back). | |
81 | * It is initialized to 1 but will turn to zero if the initialization | |
82 | * of the tracer is successful. But that is the only place that sets | |
83 | * this back to zero. | |
84 | */ | |
4fd27358 | 85 | static int tracing_disabled = 1; |
0f048701 | 86 | |
9288f99a | 87 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f SR |
88 | |
89 | static inline void ftrace_disable_cpu(void) | |
90 | { | |
91 | preempt_disable(); | |
dd17c8f7 | 92 | __this_cpu_inc(ftrace_cpu_disabled); |
d769041f SR |
93 | } |
94 | ||
95 | static inline void ftrace_enable_cpu(void) | |
96 | { | |
dd17c8f7 | 97 | __this_cpu_dec(ftrace_cpu_disabled); |
d769041f SR |
98 | preempt_enable(); |
99 | } | |
100 | ||
955b61e5 | 101 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 102 | |
944ac425 SR |
103 | /* |
104 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
105 | * | |
106 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
107 | * is set, then ftrace_dump is called. This will output the contents | |
108 | * of the ftrace buffers to the console. This is very useful for | |
109 | * capturing traces that lead to crashes and outputing it to a | |
110 | * serial console. | |
111 | * | |
112 | * It is default off, but you can enable it with either specifying | |
113 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
114 | * /proc/sys/kernel/ftrace_dump_on_oops |
115 | * Set 1 if you want to dump buffers of all CPUs | |
116 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 117 | */ |
cecbca96 FW |
118 | |
119 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 120 | |
b2821ae6 SR |
121 | static int tracing_set_tracer(const char *buf); |
122 | ||
ee6c2c1b LZ |
123 | #define MAX_TRACER_SIZE 100 |
124 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 125 | static char *default_bootup_tracer; |
d9e54076 | 126 | |
1beee96b | 127 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 128 | { |
ee6c2c1b | 129 | strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 130 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a SR |
131 | /* We are using ftrace early, expand it */ |
132 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
133 | return 1; |
134 | } | |
1beee96b | 135 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 136 | |
944ac425 SR |
137 | static int __init set_ftrace_dump_on_oops(char *str) |
138 | { | |
cecbca96 FW |
139 | if (*str++ != '=' || !*str) { |
140 | ftrace_dump_on_oops = DUMP_ALL; | |
141 | return 1; | |
142 | } | |
143 | ||
144 | if (!strcmp("orig_cpu", str)) { | |
145 | ftrace_dump_on_oops = DUMP_ORIG; | |
146 | return 1; | |
147 | } | |
148 | ||
149 | return 0; | |
944ac425 SR |
150 | } |
151 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 152 | |
cf8e3474 | 153 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
154 | { |
155 | nsec += 500; | |
156 | do_div(nsec, 1000); | |
157 | return nsec; | |
158 | } | |
159 | ||
4fcdae83 SR |
160 | /* |
161 | * The global_trace is the descriptor that holds the tracing | |
162 | * buffers for the live tracing. For each CPU, it contains | |
163 | * a link list of pages that will store trace entries. The | |
164 | * page descriptor of the pages in the memory is used to hold | |
165 | * the link list by linking the lru item in the page descriptor | |
166 | * to each of the pages in the buffer per CPU. | |
167 | * | |
168 | * For each active CPU there is a data field that holds the | |
169 | * pages for the buffer for that CPU. Each CPU has the same number | |
170 | * of pages allocated for its buffer. | |
171 | */ | |
bc0c38d1 SR |
172 | static struct trace_array global_trace; |
173 | ||
174 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
175 | ||
e77405ad SR |
176 | int filter_current_check_discard(struct ring_buffer *buffer, |
177 | struct ftrace_event_call *call, void *rec, | |
eb02ce01 TZ |
178 | struct ring_buffer_event *event) |
179 | { | |
e77405ad | 180 | return filter_check_discard(call, rec, buffer, event); |
eb02ce01 | 181 | } |
17c873ec | 182 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 183 | |
37886f6a SR |
184 | cycle_t ftrace_now(int cpu) |
185 | { | |
186 | u64 ts; | |
187 | ||
188 | /* Early boot up does not have a buffer yet */ | |
189 | if (!global_trace.buffer) | |
190 | return trace_clock_local(); | |
191 | ||
192 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
193 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
194 | ||
195 | return ts; | |
196 | } | |
bc0c38d1 | 197 | |
4fcdae83 SR |
198 | /* |
199 | * The max_tr is used to snapshot the global_trace when a maximum | |
200 | * latency is reached. Some tracers will use this to store a maximum | |
201 | * trace while it continues examining live traces. | |
202 | * | |
203 | * The buffers for the max_tr are set up the same as the global_trace. | |
204 | * When a snapshot is taken, the link list of the max_tr is swapped | |
205 | * with the link list of the global_trace and the buffers are reset for | |
206 | * the global_trace so the tracing can continue. | |
207 | */ | |
bc0c38d1 SR |
208 | static struct trace_array max_tr; |
209 | ||
9705f69e | 210 | static DEFINE_PER_CPU(struct trace_array_cpu, max_tr_data); |
bc0c38d1 | 211 | |
4fcdae83 | 212 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 213 | static int tracer_enabled = 1; |
4fcdae83 | 214 | |
9036990d SR |
215 | /** |
216 | * tracing_is_enabled - return tracer_enabled status | |
217 | * | |
218 | * This function is used by other tracers to know the status | |
219 | * of the tracer_enabled flag. Tracers may use this function | |
220 | * to know if it should enable their features when starting | |
221 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
222 | */ | |
223 | int tracing_is_enabled(void) | |
224 | { | |
225 | return tracer_enabled; | |
226 | } | |
227 | ||
4fcdae83 | 228 | /* |
3928a8a2 SR |
229 | * trace_buf_size is the size in bytes that is allocated |
230 | * for a buffer. Note, the number of bytes is always rounded | |
231 | * to page size. | |
3f5a54e3 SR |
232 | * |
233 | * This number is purposely set to a low number of 16384. | |
234 | * If the dump on oops happens, it will be much appreciated | |
235 | * to not have to wait for all that output. Anyway this can be | |
236 | * boot time and run time configurable. | |
4fcdae83 | 237 | */ |
3928a8a2 | 238 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 239 | |
3928a8a2 | 240 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 241 | |
4fcdae83 | 242 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 243 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
244 | |
245 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 246 | static struct tracer *current_trace __read_mostly; |
4fcdae83 | 247 | |
4fcdae83 SR |
248 | /* |
249 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 250 | */ |
bc0c38d1 | 251 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 252 | |
7e53bd42 LJ |
253 | /* |
254 | * serialize the access of the ring buffer | |
255 | * | |
256 | * ring buffer serializes readers, but it is low level protection. | |
257 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
258 | * are not protected by ring buffer. | |
259 | * | |
260 | * The content of events may become garbage if we allow other process consumes | |
261 | * these events concurrently: | |
262 | * A) the page of the consumed events may become a normal page | |
263 | * (not reader page) in ring buffer, and this page will be rewrited | |
264 | * by events producer. | |
265 | * B) The page of the consumed events may become a page for splice_read, | |
266 | * and this page will be returned to system. | |
267 | * | |
268 | * These primitives allow multi process access to different cpu ring buffer | |
269 | * concurrently. | |
270 | * | |
271 | * These primitives don't distinguish read-only and read-consume access. | |
272 | * Multi read-only access are also serialized. | |
273 | */ | |
274 | ||
275 | #ifdef CONFIG_SMP | |
276 | static DECLARE_RWSEM(all_cpu_access_lock); | |
277 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
278 | ||
279 | static inline void trace_access_lock(int cpu) | |
280 | { | |
281 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
282 | /* gain it for accessing the whole ring buffer. */ | |
283 | down_write(&all_cpu_access_lock); | |
284 | } else { | |
285 | /* gain it for accessing a cpu ring buffer. */ | |
286 | ||
287 | /* Firstly block other trace_access_lock(TRACE_PIPE_ALL_CPU). */ | |
288 | down_read(&all_cpu_access_lock); | |
289 | ||
290 | /* Secondly block other access to this @cpu ring buffer. */ | |
291 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
292 | } | |
293 | } | |
294 | ||
295 | static inline void trace_access_unlock(int cpu) | |
296 | { | |
297 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
298 | up_write(&all_cpu_access_lock); | |
299 | } else { | |
300 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
301 | up_read(&all_cpu_access_lock); | |
302 | } | |
303 | } | |
304 | ||
305 | static inline void trace_access_lock_init(void) | |
306 | { | |
307 | int cpu; | |
308 | ||
309 | for_each_possible_cpu(cpu) | |
310 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
311 | } | |
312 | ||
313 | #else | |
314 | ||
315 | static DEFINE_MUTEX(access_lock); | |
316 | ||
317 | static inline void trace_access_lock(int cpu) | |
318 | { | |
319 | (void)cpu; | |
320 | mutex_lock(&access_lock); | |
321 | } | |
322 | ||
323 | static inline void trace_access_unlock(int cpu) | |
324 | { | |
325 | (void)cpu; | |
326 | mutex_unlock(&access_lock); | |
327 | } | |
328 | ||
329 | static inline void trace_access_lock_init(void) | |
330 | { | |
331 | } | |
332 | ||
333 | #endif | |
334 | ||
4fcdae83 | 335 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ |
4e655519 IM |
336 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
337 | ||
ee6bce52 | 338 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 339 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 340 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
750912fa | 341 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE; |
4e655519 | 342 | |
b8de7bd1 SR |
343 | static int trace_stop_count; |
344 | static DEFINE_SPINLOCK(tracing_start_lock); | |
345 | ||
e7e2ee89 VN |
346 | static void wakeup_work_handler(struct work_struct *work) |
347 | { | |
348 | wake_up(&trace_wait); | |
349 | } | |
350 | ||
351 | static DECLARE_DELAYED_WORK(wakeup_work, wakeup_work_handler); | |
352 | ||
4fcdae83 SR |
353 | /** |
354 | * trace_wake_up - wake up tasks waiting for trace input | |
355 | * | |
e7e2ee89 VN |
356 | * Schedules a delayed work to wake up any task that is blocked on the |
357 | * trace_wait queue. These is used with trace_poll for tasks polling the | |
358 | * trace. | |
4fcdae83 | 359 | */ |
4e655519 IM |
360 | void trace_wake_up(void) |
361 | { | |
e7e2ee89 | 362 | const unsigned long delay = msecs_to_jiffies(2); |
89f19f04 AM |
363 | |
364 | if (trace_flags & TRACE_ITER_BLOCK) | |
365 | return; | |
e7e2ee89 | 366 | schedule_delayed_work(&wakeup_work, delay); |
4e655519 | 367 | } |
bc0c38d1 | 368 | |
3928a8a2 | 369 | static int __init set_buf_size(char *str) |
bc0c38d1 | 370 | { |
3928a8a2 | 371 | unsigned long buf_size; |
c6caeeb1 | 372 | |
bc0c38d1 SR |
373 | if (!str) |
374 | return 0; | |
9d612bef | 375 | buf_size = memparse(str, &str); |
c6caeeb1 | 376 | /* nr_entries can not be zero */ |
9d612bef | 377 | if (buf_size == 0) |
c6caeeb1 | 378 | return 0; |
3928a8a2 | 379 | trace_buf_size = buf_size; |
bc0c38d1 SR |
380 | return 1; |
381 | } | |
3928a8a2 | 382 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 383 | |
0e950173 TB |
384 | static int __init set_tracing_thresh(char *str) |
385 | { | |
386 | unsigned long threshhold; | |
387 | int ret; | |
388 | ||
389 | if (!str) | |
390 | return 0; | |
391 | ret = strict_strtoul(str, 0, &threshhold); | |
392 | if (ret < 0) | |
393 | return 0; | |
394 | tracing_thresh = threshhold * 1000; | |
395 | return 1; | |
396 | } | |
397 | __setup("tracing_thresh=", set_tracing_thresh); | |
398 | ||
57f50be1 SR |
399 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
400 | { | |
401 | return nsecs / 1000; | |
402 | } | |
403 | ||
4fcdae83 | 404 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
405 | static const char *trace_options[] = { |
406 | "print-parent", | |
407 | "sym-offset", | |
408 | "sym-addr", | |
409 | "verbose", | |
f9896bf3 | 410 | "raw", |
5e3ca0ec | 411 | "hex", |
cb0f12aa | 412 | "bin", |
2a2cc8f7 | 413 | "block", |
86387f7e | 414 | "stacktrace", |
5e1607a0 | 415 | "trace_printk", |
b2a866f9 | 416 | "ftrace_preempt", |
9f029e83 | 417 | "branch", |
12ef7d44 | 418 | "annotate", |
02b67518 | 419 | "userstacktrace", |
b54d3de9 | 420 | "sym-userobj", |
66896a85 | 421 | "printk-msg-only", |
c4a8e8be | 422 | "context-info", |
c032ef64 | 423 | "latency-format", |
be6f164a | 424 | "sleep-time", |
a2a16d6a | 425 | "graph-time", |
e870e9a1 | 426 | "record-cmd", |
750912fa | 427 | "overwrite", |
bc0c38d1 SR |
428 | NULL |
429 | }; | |
430 | ||
5079f326 Z |
431 | static struct { |
432 | u64 (*func)(void); | |
433 | const char *name; | |
434 | } trace_clocks[] = { | |
435 | { trace_clock_local, "local" }, | |
436 | { trace_clock_global, "global" }, | |
437 | }; | |
438 | ||
439 | int trace_clock_id; | |
440 | ||
b63f39ea | 441 | /* |
442 | * trace_parser_get_init - gets the buffer for trace parser | |
443 | */ | |
444 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
445 | { | |
446 | memset(parser, 0, sizeof(*parser)); | |
447 | ||
448 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
449 | if (!parser->buffer) | |
450 | return 1; | |
451 | ||
452 | parser->size = size; | |
453 | return 0; | |
454 | } | |
455 | ||
456 | /* | |
457 | * trace_parser_put - frees the buffer for trace parser | |
458 | */ | |
459 | void trace_parser_put(struct trace_parser *parser) | |
460 | { | |
461 | kfree(parser->buffer); | |
462 | } | |
463 | ||
464 | /* | |
465 | * trace_get_user - reads the user input string separated by space | |
466 | * (matched by isspace(ch)) | |
467 | * | |
468 | * For each string found the 'struct trace_parser' is updated, | |
469 | * and the function returns. | |
470 | * | |
471 | * Returns number of bytes read. | |
472 | * | |
473 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
474 | */ | |
475 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
476 | size_t cnt, loff_t *ppos) | |
477 | { | |
478 | char ch; | |
479 | size_t read = 0; | |
480 | ssize_t ret; | |
481 | ||
482 | if (!*ppos) | |
483 | trace_parser_clear(parser); | |
484 | ||
485 | ret = get_user(ch, ubuf++); | |
486 | if (ret) | |
487 | goto out; | |
488 | ||
489 | read++; | |
490 | cnt--; | |
491 | ||
492 | /* | |
493 | * The parser is not finished with the last write, | |
494 | * continue reading the user input without skipping spaces. | |
495 | */ | |
496 | if (!parser->cont) { | |
497 | /* skip white space */ | |
498 | while (cnt && isspace(ch)) { | |
499 | ret = get_user(ch, ubuf++); | |
500 | if (ret) | |
501 | goto out; | |
502 | read++; | |
503 | cnt--; | |
504 | } | |
505 | ||
506 | /* only spaces were written */ | |
507 | if (isspace(ch)) { | |
508 | *ppos += read; | |
509 | ret = read; | |
510 | goto out; | |
511 | } | |
512 | ||
513 | parser->idx = 0; | |
514 | } | |
515 | ||
516 | /* read the non-space input */ | |
517 | while (cnt && !isspace(ch)) { | |
3c235a33 | 518 | if (parser->idx < parser->size - 1) |
b63f39ea | 519 | parser->buffer[parser->idx++] = ch; |
520 | else { | |
521 | ret = -EINVAL; | |
522 | goto out; | |
523 | } | |
524 | ret = get_user(ch, ubuf++); | |
525 | if (ret) | |
526 | goto out; | |
527 | read++; | |
528 | cnt--; | |
529 | } | |
530 | ||
531 | /* We either got finished input or we have to wait for another call. */ | |
532 | if (isspace(ch)) { | |
533 | parser->buffer[parser->idx] = 0; | |
534 | parser->cont = false; | |
535 | } else { | |
536 | parser->cont = true; | |
537 | parser->buffer[parser->idx++] = ch; | |
538 | } | |
539 | ||
540 | *ppos += read; | |
541 | ret = read; | |
542 | ||
543 | out: | |
544 | return ret; | |
545 | } | |
546 | ||
6c6c2796 PP |
547 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
548 | { | |
549 | int len; | |
550 | int ret; | |
551 | ||
2dc5d12b SR |
552 | if (!cnt) |
553 | return 0; | |
554 | ||
6c6c2796 PP |
555 | if (s->len <= s->readpos) |
556 | return -EBUSY; | |
557 | ||
558 | len = s->len - s->readpos; | |
559 | if (cnt > len) | |
560 | cnt = len; | |
561 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 562 | if (ret == cnt) |
6c6c2796 PP |
563 | return -EFAULT; |
564 | ||
2dc5d12b SR |
565 | cnt -= ret; |
566 | ||
e74da523 | 567 | s->readpos += cnt; |
6c6c2796 | 568 | return cnt; |
214023c3 SR |
569 | } |
570 | ||
b8b94265 | 571 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
572 | { |
573 | int len; | |
574 | void *ret; | |
575 | ||
576 | if (s->len <= s->readpos) | |
577 | return -EBUSY; | |
578 | ||
579 | len = s->len - s->readpos; | |
580 | if (cnt > len) | |
581 | cnt = len; | |
582 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
583 | if (!ret) | |
584 | return -EFAULT; | |
585 | ||
e74da523 | 586 | s->readpos += cnt; |
3c56819b EGM |
587 | return cnt; |
588 | } | |
589 | ||
5d4a9dba SR |
590 | /* |
591 | * ftrace_max_lock is used to protect the swapping of buffers | |
592 | * when taking a max snapshot. The buffers themselves are | |
593 | * protected by per_cpu spinlocks. But the action of the swap | |
594 | * needs its own lock. | |
595 | * | |
445c8951 | 596 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
597 | * with performance when lockdep debugging is enabled. |
598 | * | |
599 | * It is also used in other places outside the update_max_tr | |
600 | * so it needs to be defined outside of the | |
601 | * CONFIG_TRACER_MAX_TRACE. | |
602 | */ | |
445c8951 | 603 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 604 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba | 605 | |
0e950173 TB |
606 | unsigned long __read_mostly tracing_thresh; |
607 | ||
5d4a9dba SR |
608 | #ifdef CONFIG_TRACER_MAX_TRACE |
609 | unsigned long __read_mostly tracing_max_latency; | |
5d4a9dba SR |
610 | |
611 | /* | |
612 | * Copy the new maximum trace into the separate maximum-trace | |
613 | * structure. (this way the maximum trace is permanently saved, | |
614 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
615 | */ | |
616 | static void | |
617 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
618 | { | |
619 | struct trace_array_cpu *data = tr->data[cpu]; | |
1acaa1b2 | 620 | struct trace_array_cpu *max_data; |
5d4a9dba SR |
621 | |
622 | max_tr.cpu = cpu; | |
623 | max_tr.time_start = data->preempt_timestamp; | |
624 | ||
8248ac05 SR |
625 | max_data = max_tr.data[cpu]; |
626 | max_data->saved_latency = tracing_max_latency; | |
627 | max_data->critical_start = data->critical_start; | |
628 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 629 | |
1acaa1b2 | 630 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 SR |
631 | max_data->pid = tsk->pid; |
632 | max_data->uid = task_uid(tsk); | |
633 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
634 | max_data->policy = tsk->policy; | |
635 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
636 | |
637 | /* record this tasks comm */ | |
638 | tracing_record_cmdline(tsk); | |
639 | } | |
640 | ||
4fcdae83 SR |
641 | /** |
642 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
643 | * @tr: tracer | |
644 | * @tsk: the task with the latency | |
645 | * @cpu: The cpu that initiated the trace. | |
646 | * | |
647 | * Flip the buffers between the @tr and the max_tr and record information | |
648 | * about which task was the cause of this latency. | |
649 | */ | |
e309b41d | 650 | void |
bc0c38d1 SR |
651 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
652 | { | |
3928a8a2 | 653 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 654 | |
b8de7bd1 SR |
655 | if (trace_stop_count) |
656 | return; | |
657 | ||
4c11d7ae | 658 | WARN_ON_ONCE(!irqs_disabled()); |
ef710e10 KM |
659 | if (!current_trace->use_max_tr) { |
660 | WARN_ON_ONCE(1); | |
661 | return; | |
662 | } | |
0199c4e6 | 663 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
664 | |
665 | tr->buffer = max_tr.buffer; | |
666 | max_tr.buffer = buf; | |
667 | ||
bc0c38d1 | 668 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 669 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
670 | } |
671 | ||
672 | /** | |
673 | * update_max_tr_single - only copy one trace over, and reset the rest | |
674 | * @tr - tracer | |
675 | * @tsk - task with the latency | |
676 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
677 | * |
678 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 679 | */ |
e309b41d | 680 | void |
bc0c38d1 SR |
681 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
682 | { | |
3928a8a2 | 683 | int ret; |
bc0c38d1 | 684 | |
b8de7bd1 SR |
685 | if (trace_stop_count) |
686 | return; | |
687 | ||
4c11d7ae | 688 | WARN_ON_ONCE(!irqs_disabled()); |
ef710e10 KM |
689 | if (!current_trace->use_max_tr) { |
690 | WARN_ON_ONCE(1); | |
691 | return; | |
692 | } | |
693 | ||
0199c4e6 | 694 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 695 | |
d769041f SR |
696 | ftrace_disable_cpu(); |
697 | ||
3928a8a2 SR |
698 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); |
699 | ||
e8165dbb SR |
700 | if (ret == -EBUSY) { |
701 | /* | |
702 | * We failed to swap the buffer due to a commit taking | |
703 | * place on this CPU. We fail to record, but we reset | |
704 | * the max trace buffer (no one writes directly to it) | |
705 | * and flag that it failed. | |
706 | */ | |
707 | trace_array_printk(&max_tr, _THIS_IP_, | |
708 | "Failed to swap buffers due to commit in progress\n"); | |
709 | } | |
710 | ||
d769041f SR |
711 | ftrace_enable_cpu(); |
712 | ||
e8165dbb | 713 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
714 | |
715 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 716 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 717 | } |
5d4a9dba | 718 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 719 | |
4fcdae83 SR |
720 | /** |
721 | * register_tracer - register a tracer with the ftrace system. | |
722 | * @type - the plugin for the tracer | |
723 | * | |
724 | * Register a new plugin tracer. | |
725 | */ | |
bc0c38d1 | 726 | int register_tracer(struct tracer *type) |
e7669b8e HE |
727 | __releases(kernel_lock) |
728 | __acquires(kernel_lock) | |
bc0c38d1 SR |
729 | { |
730 | struct tracer *t; | |
bc0c38d1 SR |
731 | int ret = 0; |
732 | ||
733 | if (!type->name) { | |
734 | pr_info("Tracer must have a name\n"); | |
735 | return -1; | |
736 | } | |
737 | ||
24a461d5 | 738 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
739 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
740 | return -1; | |
741 | } | |
742 | ||
bc0c38d1 | 743 | mutex_lock(&trace_types_lock); |
86fa2f60 | 744 | |
8e1b82e0 FW |
745 | tracing_selftest_running = true; |
746 | ||
bc0c38d1 SR |
747 | for (t = trace_types; t; t = t->next) { |
748 | if (strcmp(type->name, t->name) == 0) { | |
749 | /* already found */ | |
ee6c2c1b | 750 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
751 | type->name); |
752 | ret = -1; | |
753 | goto out; | |
754 | } | |
755 | } | |
756 | ||
adf9f195 FW |
757 | if (!type->set_flag) |
758 | type->set_flag = &dummy_set_flag; | |
759 | if (!type->flags) | |
760 | type->flags = &dummy_tracer_flags; | |
761 | else | |
762 | if (!type->flags->opts) | |
763 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
764 | if (!type->wait_pipe) |
765 | type->wait_pipe = default_wait_pipe; | |
766 | ||
adf9f195 | 767 | |
60a11774 | 768 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 769 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 770 | struct tracer *saved_tracer = current_trace; |
60a11774 | 771 | struct trace_array *tr = &global_trace; |
ff32504f | 772 | |
60a11774 SR |
773 | /* |
774 | * Run a selftest on this tracer. | |
775 | * Here we reset the trace buffer, and set the current | |
776 | * tracer to be this tracer. The tracer can then run some | |
777 | * internal tracing to verify that everything is in order. | |
778 | * If we fail, we do not register this tracer. | |
779 | */ | |
76f0d073 | 780 | tracing_reset_online_cpus(tr); |
86fa2f60 | 781 | |
60a11774 | 782 | current_trace = type; |
4a0b1665 SR |
783 | |
784 | /* If we expanded the buffers, make sure the max is expanded too */ | |
785 | if (ring_buffer_expanded && type->use_max_tr) | |
786 | ring_buffer_resize(max_tr.buffer, trace_buf_size); | |
787 | ||
60a11774 SR |
788 | /* the test is responsible for initializing and enabling */ |
789 | pr_info("Testing tracer %s: ", type->name); | |
790 | ret = type->selftest(type, tr); | |
791 | /* the test is responsible for resetting too */ | |
792 | current_trace = saved_tracer; | |
60a11774 SR |
793 | if (ret) { |
794 | printk(KERN_CONT "FAILED!\n"); | |
795 | goto out; | |
796 | } | |
1d4db00a | 797 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 798 | tracing_reset_online_cpus(tr); |
86fa2f60 | 799 | |
4a0b1665 SR |
800 | /* Shrink the max buffer again */ |
801 | if (ring_buffer_expanded && type->use_max_tr) | |
802 | ring_buffer_resize(max_tr.buffer, 1); | |
803 | ||
60a11774 SR |
804 | printk(KERN_CONT "PASSED\n"); |
805 | } | |
806 | #endif | |
807 | ||
bc0c38d1 SR |
808 | type->next = trace_types; |
809 | trace_types = type; | |
60a11774 | 810 | |
bc0c38d1 | 811 | out: |
8e1b82e0 | 812 | tracing_selftest_running = false; |
bc0c38d1 SR |
813 | mutex_unlock(&trace_types_lock); |
814 | ||
dac74940 SR |
815 | if (ret || !default_bootup_tracer) |
816 | goto out_unlock; | |
817 | ||
ee6c2c1b | 818 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
819 | goto out_unlock; |
820 | ||
821 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
822 | /* Do we want this tracer to start on bootup? */ | |
823 | tracing_set_tracer(type->name); | |
824 | default_bootup_tracer = NULL; | |
825 | /* disable other selftests, since this will break it. */ | |
826 | tracing_selftest_disabled = 1; | |
b2821ae6 | 827 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
828 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
829 | type->name); | |
b2821ae6 | 830 | #endif |
b2821ae6 | 831 | |
dac74940 | 832 | out_unlock: |
bc0c38d1 SR |
833 | return ret; |
834 | } | |
835 | ||
836 | void unregister_tracer(struct tracer *type) | |
837 | { | |
838 | struct tracer **t; | |
bc0c38d1 SR |
839 | |
840 | mutex_lock(&trace_types_lock); | |
841 | for (t = &trace_types; *t; t = &(*t)->next) { | |
842 | if (*t == type) | |
843 | goto found; | |
844 | } | |
ee6c2c1b | 845 | pr_info("Tracer %s not registered\n", type->name); |
bc0c38d1 SR |
846 | goto out; |
847 | ||
848 | found: | |
849 | *t = (*t)->next; | |
b5db03c4 ACM |
850 | |
851 | if (type == current_trace && tracer_enabled) { | |
852 | tracer_enabled = 0; | |
853 | tracing_stop(); | |
854 | if (current_trace->stop) | |
855 | current_trace->stop(&global_trace); | |
856 | current_trace = &nop_trace; | |
857 | } | |
ee6c2c1b | 858 | out: |
bc0c38d1 SR |
859 | mutex_unlock(&trace_types_lock); |
860 | } | |
861 | ||
283740c6 | 862 | static void __tracing_reset(struct ring_buffer *buffer, int cpu) |
bc0c38d1 | 863 | { |
d769041f | 864 | ftrace_disable_cpu(); |
283740c6 | 865 | ring_buffer_reset_cpu(buffer, cpu); |
d769041f | 866 | ftrace_enable_cpu(); |
bc0c38d1 SR |
867 | } |
868 | ||
f633903a SR |
869 | void tracing_reset(struct trace_array *tr, int cpu) |
870 | { | |
871 | struct ring_buffer *buffer = tr->buffer; | |
872 | ||
873 | ring_buffer_record_disable(buffer); | |
874 | ||
875 | /* Make sure all commits have finished */ | |
876 | synchronize_sched(); | |
283740c6 | 877 | __tracing_reset(buffer, cpu); |
f633903a SR |
878 | |
879 | ring_buffer_record_enable(buffer); | |
880 | } | |
881 | ||
213cc060 PE |
882 | void tracing_reset_online_cpus(struct trace_array *tr) |
883 | { | |
621968cd | 884 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
885 | int cpu; |
886 | ||
621968cd SR |
887 | ring_buffer_record_disable(buffer); |
888 | ||
889 | /* Make sure all commits have finished */ | |
890 | synchronize_sched(); | |
891 | ||
213cc060 PE |
892 | tr->time_start = ftrace_now(tr->cpu); |
893 | ||
894 | for_each_online_cpu(cpu) | |
283740c6 | 895 | __tracing_reset(buffer, cpu); |
621968cd SR |
896 | |
897 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
898 | } |
899 | ||
9456f0fa SR |
900 | void tracing_reset_current(int cpu) |
901 | { | |
902 | tracing_reset(&global_trace, cpu); | |
903 | } | |
904 | ||
905 | void tracing_reset_current_online_cpus(void) | |
906 | { | |
907 | tracing_reset_online_cpus(&global_trace); | |
908 | } | |
909 | ||
bc0c38d1 | 910 | #define SAVED_CMDLINES 128 |
2c7eea4c | 911 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
912 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
913 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
914 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
915 | static int cmdline_idx; | |
edc35bd7 | 916 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 917 | |
25b0b44a | 918 | /* temporary disable recording */ |
4fd27358 | 919 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
920 | |
921 | static void trace_init_cmdlines(void) | |
922 | { | |
2c7eea4c TG |
923 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
924 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
925 | cmdline_idx = 0; |
926 | } | |
927 | ||
b5130b1e CE |
928 | int is_tracing_stopped(void) |
929 | { | |
930 | return trace_stop_count; | |
931 | } | |
932 | ||
69bb54ec SR |
933 | /** |
934 | * ftrace_off_permanent - disable all ftrace code permanently | |
935 | * | |
936 | * This should only be called when a serious anomally has | |
937 | * been detected. This will turn off the function tracing, | |
938 | * ring buffers, and other tracing utilites. It takes no | |
939 | * locks and can be called from any context. | |
940 | */ | |
941 | void ftrace_off_permanent(void) | |
942 | { | |
943 | tracing_disabled = 1; | |
944 | ftrace_stop(); | |
945 | tracing_off_permanent(); | |
946 | } | |
947 | ||
0f048701 SR |
948 | /** |
949 | * tracing_start - quick start of the tracer | |
950 | * | |
951 | * If tracing is enabled but was stopped by tracing_stop, | |
952 | * this will start the tracer back up. | |
953 | */ | |
954 | void tracing_start(void) | |
955 | { | |
956 | struct ring_buffer *buffer; | |
957 | unsigned long flags; | |
958 | ||
959 | if (tracing_disabled) | |
960 | return; | |
961 | ||
962 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
963 | if (--trace_stop_count) { |
964 | if (trace_stop_count < 0) { | |
965 | /* Someone screwed up their debugging */ | |
966 | WARN_ON_ONCE(1); | |
967 | trace_stop_count = 0; | |
968 | } | |
0f048701 SR |
969 | goto out; |
970 | } | |
971 | ||
a2f80714 SR |
972 | /* Prevent the buffers from switching */ |
973 | arch_spin_lock(&ftrace_max_lock); | |
0f048701 SR |
974 | |
975 | buffer = global_trace.buffer; | |
976 | if (buffer) | |
977 | ring_buffer_record_enable(buffer); | |
978 | ||
979 | buffer = max_tr.buffer; | |
980 | if (buffer) | |
981 | ring_buffer_record_enable(buffer); | |
982 | ||
a2f80714 SR |
983 | arch_spin_unlock(&ftrace_max_lock); |
984 | ||
0f048701 SR |
985 | ftrace_start(); |
986 | out: | |
987 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
988 | } | |
989 | ||
990 | /** | |
991 | * tracing_stop - quick stop of the tracer | |
992 | * | |
993 | * Light weight way to stop tracing. Use in conjunction with | |
994 | * tracing_start. | |
995 | */ | |
996 | void tracing_stop(void) | |
997 | { | |
998 | struct ring_buffer *buffer; | |
999 | unsigned long flags; | |
1000 | ||
1001 | ftrace_stop(); | |
1002 | spin_lock_irqsave(&tracing_start_lock, flags); | |
1003 | if (trace_stop_count++) | |
1004 | goto out; | |
1005 | ||
a2f80714 SR |
1006 | /* Prevent the buffers from switching */ |
1007 | arch_spin_lock(&ftrace_max_lock); | |
1008 | ||
0f048701 SR |
1009 | buffer = global_trace.buffer; |
1010 | if (buffer) | |
1011 | ring_buffer_record_disable(buffer); | |
1012 | ||
1013 | buffer = max_tr.buffer; | |
1014 | if (buffer) | |
1015 | ring_buffer_record_disable(buffer); | |
1016 | ||
a2f80714 SR |
1017 | arch_spin_unlock(&ftrace_max_lock); |
1018 | ||
0f048701 SR |
1019 | out: |
1020 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
1021 | } | |
1022 | ||
e309b41d | 1023 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1024 | |
e309b41d | 1025 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1026 | { |
a635cf04 | 1027 | unsigned pid, idx; |
bc0c38d1 SR |
1028 | |
1029 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
1030 | return; | |
1031 | ||
1032 | /* | |
1033 | * It's not the end of the world if we don't get | |
1034 | * the lock, but we also don't want to spin | |
1035 | * nor do we want to disable interrupts, | |
1036 | * so if we miss here, then better luck next time. | |
1037 | */ | |
0199c4e6 | 1038 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
1039 | return; |
1040 | ||
1041 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1042 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1043 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1044 | ||
a635cf04 CE |
1045 | /* |
1046 | * Check whether the cmdline buffer at idx has a pid | |
1047 | * mapped. We are going to overwrite that entry so we | |
1048 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1049 | * would read the new comm for the old pid. | |
1050 | */ | |
1051 | pid = map_cmdline_to_pid[idx]; | |
1052 | if (pid != NO_CMDLINE_MAP) | |
1053 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1054 | |
a635cf04 | 1055 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1056 | map_pid_to_cmdline[tsk->pid] = idx; |
1057 | ||
1058 | cmdline_idx = idx; | |
1059 | } | |
1060 | ||
1061 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1062 | ||
0199c4e6 | 1063 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1064 | } |
1065 | ||
4ca53085 | 1066 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1067 | { |
bc0c38d1 SR |
1068 | unsigned map; |
1069 | ||
4ca53085 SR |
1070 | if (!pid) { |
1071 | strcpy(comm, "<idle>"); | |
1072 | return; | |
1073 | } | |
bc0c38d1 | 1074 | |
74bf4076 SR |
1075 | if (WARN_ON_ONCE(pid < 0)) { |
1076 | strcpy(comm, "<XXX>"); | |
1077 | return; | |
1078 | } | |
1079 | ||
4ca53085 SR |
1080 | if (pid > PID_MAX_DEFAULT) { |
1081 | strcpy(comm, "<...>"); | |
1082 | return; | |
1083 | } | |
bc0c38d1 | 1084 | |
5b6045a9 | 1085 | preempt_disable(); |
0199c4e6 | 1086 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1087 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1088 | if (map != NO_CMDLINE_MAP) |
1089 | strcpy(comm, saved_cmdlines[map]); | |
1090 | else | |
1091 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1092 | |
0199c4e6 | 1093 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1094 | preempt_enable(); |
bc0c38d1 SR |
1095 | } |
1096 | ||
e309b41d | 1097 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1098 | { |
18aecd36 TG |
1099 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
1100 | !tracing_is_on()) | |
bc0c38d1 SR |
1101 | return; |
1102 | ||
1103 | trace_save_cmdline(tsk); | |
1104 | } | |
1105 | ||
45dcd8b8 | 1106 | void |
38697053 SR |
1107 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1108 | int pc) | |
bc0c38d1 SR |
1109 | { |
1110 | struct task_struct *tsk = current; | |
bc0c38d1 | 1111 | |
777e208d SR |
1112 | entry->preempt_count = pc & 0xff; |
1113 | entry->pid = (tsk) ? tsk->pid : 0; | |
a3a4a5ac | 1114 | entry->padding = 0; |
777e208d | 1115 | entry->flags = |
9244489a | 1116 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1117 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1118 | #else |
1119 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1120 | #endif | |
bc0c38d1 SR |
1121 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1122 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1123 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1124 | } | |
f413cdb8 | 1125 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1126 | |
e77405ad SR |
1127 | struct ring_buffer_event * |
1128 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1129 | int type, | |
1130 | unsigned long len, | |
1131 | unsigned long flags, int pc) | |
51a763dd ACM |
1132 | { |
1133 | struct ring_buffer_event *event; | |
1134 | ||
e77405ad | 1135 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1136 | if (event != NULL) { |
1137 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1138 | ||
1139 | tracing_generic_entry_update(ent, flags, pc); | |
1140 | ent->type = type; | |
1141 | } | |
1142 | ||
1143 | return event; | |
1144 | } | |
51a763dd | 1145 | |
e77405ad SR |
1146 | static inline void |
1147 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1148 | struct ring_buffer_event *event, | |
1149 | unsigned long flags, int pc, | |
1150 | int wake) | |
51a763dd | 1151 | { |
e77405ad | 1152 | ring_buffer_unlock_commit(buffer, event); |
51a763dd | 1153 | |
e77405ad SR |
1154 | ftrace_trace_stack(buffer, flags, 6, pc); |
1155 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1156 | |
1157 | if (wake) | |
1158 | trace_wake_up(); | |
1159 | } | |
1160 | ||
e77405ad SR |
1161 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1162 | struct ring_buffer_event *event, | |
1163 | unsigned long flags, int pc) | |
07edf712 | 1164 | { |
e77405ad | 1165 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
51a763dd ACM |
1166 | } |
1167 | ||
ef5580d0 | 1168 | struct ring_buffer_event * |
e77405ad SR |
1169 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1170 | int type, unsigned long len, | |
ef5580d0 SR |
1171 | unsigned long flags, int pc) |
1172 | { | |
e77405ad SR |
1173 | *current_rb = global_trace.buffer; |
1174 | return trace_buffer_lock_reserve(*current_rb, | |
ef5580d0 SR |
1175 | type, len, flags, pc); |
1176 | } | |
94487d6d | 1177 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1178 | |
e77405ad SR |
1179 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1180 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1181 | unsigned long flags, int pc) |
1182 | { | |
e77405ad | 1183 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
07edf712 | 1184 | } |
94487d6d | 1185 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1186 | |
e77405ad SR |
1187 | void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer, |
1188 | struct ring_buffer_event *event, | |
1189 | unsigned long flags, int pc) | |
07edf712 | 1190 | { |
e77405ad | 1191 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 0); |
77d9f465 | 1192 | } |
94487d6d | 1193 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 | 1194 | |
e77405ad SR |
1195 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1196 | struct ring_buffer_event *event) | |
77d9f465 | 1197 | { |
e77405ad | 1198 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1199 | } |
12acd473 | 1200 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1201 | |
e309b41d | 1202 | void |
7be42151 | 1203 | trace_function(struct trace_array *tr, |
38697053 SR |
1204 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1205 | int pc) | |
bc0c38d1 | 1206 | { |
e1112b4d | 1207 | struct ftrace_event_call *call = &event_function; |
e77405ad | 1208 | struct ring_buffer *buffer = tr->buffer; |
3928a8a2 | 1209 | struct ring_buffer_event *event; |
777e208d | 1210 | struct ftrace_entry *entry; |
bc0c38d1 | 1211 | |
d769041f | 1212 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1213 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1214 | return; |
1215 | ||
e77405ad | 1216 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1217 | flags, pc); |
3928a8a2 SR |
1218 | if (!event) |
1219 | return; | |
1220 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1221 | entry->ip = ip; |
1222 | entry->parent_ip = parent_ip; | |
e1112b4d | 1223 | |
e77405ad SR |
1224 | if (!filter_check_discard(call, entry, buffer, event)) |
1225 | ring_buffer_unlock_commit(buffer, event); | |
bc0c38d1 SR |
1226 | } |
1227 | ||
e309b41d | 1228 | void |
2e0f5761 | 1229 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1230 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1231 | int pc) | |
2e0f5761 IM |
1232 | { |
1233 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1234 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1235 | } |
1236 | ||
c0a0d0d3 | 1237 | #ifdef CONFIG_STACKTRACE |
e77405ad | 1238 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 SR |
1239 | unsigned long flags, |
1240 | int skip, int pc) | |
86387f7e | 1241 | { |
e1112b4d | 1242 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1243 | struct ring_buffer_event *event; |
777e208d | 1244 | struct stack_entry *entry; |
86387f7e IM |
1245 | struct stack_trace trace; |
1246 | ||
e77405ad | 1247 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
51a763dd | 1248 | sizeof(*entry), flags, pc); |
3928a8a2 SR |
1249 | if (!event) |
1250 | return; | |
1251 | entry = ring_buffer_event_data(event); | |
777e208d | 1252 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
1253 | |
1254 | trace.nr_entries = 0; | |
1255 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1256 | trace.skip = skip; | |
777e208d | 1257 | trace.entries = entry->caller; |
86387f7e IM |
1258 | |
1259 | save_stack_trace(&trace); | |
e77405ad SR |
1260 | if (!filter_check_discard(call, entry, buffer, event)) |
1261 | ring_buffer_unlock_commit(buffer, event); | |
f0a920d5 IM |
1262 | } |
1263 | ||
e77405ad SR |
1264 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1265 | int skip, int pc) | |
53614991 SR |
1266 | { |
1267 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1268 | return; | |
1269 | ||
e77405ad | 1270 | __ftrace_trace_stack(buffer, flags, skip, pc); |
53614991 SR |
1271 | } |
1272 | ||
c0a0d0d3 FW |
1273 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1274 | int pc) | |
38697053 | 1275 | { |
e77405ad | 1276 | __ftrace_trace_stack(tr->buffer, flags, skip, pc); |
38697053 SR |
1277 | } |
1278 | ||
03889384 SR |
1279 | /** |
1280 | * trace_dump_stack - record a stack back trace in the trace buffer | |
1281 | */ | |
1282 | void trace_dump_stack(void) | |
1283 | { | |
1284 | unsigned long flags; | |
1285 | ||
1286 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1287 | return; |
03889384 SR |
1288 | |
1289 | local_save_flags(flags); | |
1290 | ||
1291 | /* skipping 3 traces, seems to get us at the caller of this function */ | |
1292 | __ftrace_trace_stack(global_trace.buffer, flags, 3, preempt_count()); | |
1293 | } | |
1294 | ||
91e86e56 SR |
1295 | static DEFINE_PER_CPU(int, user_stack_count); |
1296 | ||
e77405ad SR |
1297 | void |
1298 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1299 | { |
e1112b4d | 1300 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1301 | struct ring_buffer_event *event; |
02b67518 TE |
1302 | struct userstack_entry *entry; |
1303 | struct stack_trace trace; | |
02b67518 TE |
1304 | |
1305 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1306 | return; | |
1307 | ||
b6345879 SR |
1308 | /* |
1309 | * NMIs can not handle page faults, even with fix ups. | |
1310 | * The save user stack can (and often does) fault. | |
1311 | */ | |
1312 | if (unlikely(in_nmi())) | |
1313 | return; | |
02b67518 | 1314 | |
91e86e56 SR |
1315 | /* |
1316 | * prevent recursion, since the user stack tracing may | |
1317 | * trigger other kernel events. | |
1318 | */ | |
1319 | preempt_disable(); | |
1320 | if (__this_cpu_read(user_stack_count)) | |
1321 | goto out; | |
1322 | ||
1323 | __this_cpu_inc(user_stack_count); | |
1324 | ||
e77405ad | 1325 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1326 | sizeof(*entry), flags, pc); |
02b67518 | 1327 | if (!event) |
1dbd1951 | 1328 | goto out_drop_count; |
02b67518 | 1329 | entry = ring_buffer_event_data(event); |
02b67518 | 1330 | |
48659d31 | 1331 | entry->tgid = current->tgid; |
02b67518 TE |
1332 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1333 | ||
1334 | trace.nr_entries = 0; | |
1335 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1336 | trace.skip = 0; | |
1337 | trace.entries = entry->caller; | |
1338 | ||
1339 | save_stack_trace_user(&trace); | |
e77405ad SR |
1340 | if (!filter_check_discard(call, entry, buffer, event)) |
1341 | ring_buffer_unlock_commit(buffer, event); | |
91e86e56 | 1342 | |
1dbd1951 | 1343 | out_drop_count: |
91e86e56 | 1344 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1345 | out: |
1346 | preempt_enable(); | |
02b67518 TE |
1347 | } |
1348 | ||
4fd27358 HE |
1349 | #ifdef UNUSED |
1350 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1351 | { |
7be42151 | 1352 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1353 | } |
4fd27358 | 1354 | #endif /* UNUSED */ |
02b67518 | 1355 | |
c0a0d0d3 FW |
1356 | #endif /* CONFIG_STACKTRACE */ |
1357 | ||
769b0441 | 1358 | /** |
48ead020 | 1359 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1360 | * |
1361 | */ | |
40ce74f1 | 1362 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1363 | { |
445c8951 | 1364 | static arch_spinlock_t trace_buf_lock = |
edc35bd7 | 1365 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
769b0441 FW |
1366 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1367 | ||
e1112b4d | 1368 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1369 | struct ring_buffer_event *event; |
e77405ad | 1370 | struct ring_buffer *buffer; |
769b0441 FW |
1371 | struct trace_array *tr = &global_trace; |
1372 | struct trace_array_cpu *data; | |
48ead020 | 1373 | struct bprint_entry *entry; |
769b0441 | 1374 | unsigned long flags; |
3189cdb3 | 1375 | int disable; |
769b0441 FW |
1376 | int cpu, len = 0, size, pc; |
1377 | ||
1378 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1379 | return 0; | |
1380 | ||
1381 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1382 | pause_graph_tracing(); | |
1383 | ||
1384 | pc = preempt_count(); | |
5168ae50 | 1385 | preempt_disable_notrace(); |
769b0441 FW |
1386 | cpu = raw_smp_processor_id(); |
1387 | data = tr->data[cpu]; | |
1388 | ||
3189cdb3 SR |
1389 | disable = atomic_inc_return(&data->disabled); |
1390 | if (unlikely(disable != 1)) | |
769b0441 FW |
1391 | goto out; |
1392 | ||
80370cb7 SR |
1393 | /* Lockdep uses trace_printk for lock tracing */ |
1394 | local_irq_save(flags); | |
0199c4e6 | 1395 | arch_spin_lock(&trace_buf_lock); |
769b0441 FW |
1396 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1397 | ||
1398 | if (len > TRACE_BUF_SIZE || len < 0) | |
1399 | goto out_unlock; | |
1400 | ||
1401 | size = sizeof(*entry) + sizeof(u32) * len; | |
e77405ad SR |
1402 | buffer = tr->buffer; |
1403 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, | |
1404 | flags, pc); | |
769b0441 FW |
1405 | if (!event) |
1406 | goto out_unlock; | |
1407 | entry = ring_buffer_event_data(event); | |
1408 | entry->ip = ip; | |
769b0441 FW |
1409 | entry->fmt = fmt; |
1410 | ||
1411 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
d931369b | 1412 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1413 | ring_buffer_unlock_commit(buffer, event); |
d931369b SR |
1414 | ftrace_trace_stack(buffer, flags, 6, pc); |
1415 | } | |
769b0441 FW |
1416 | |
1417 | out_unlock: | |
0199c4e6 | 1418 | arch_spin_unlock(&trace_buf_lock); |
80370cb7 | 1419 | local_irq_restore(flags); |
769b0441 FW |
1420 | |
1421 | out: | |
3189cdb3 | 1422 | atomic_dec_return(&data->disabled); |
5168ae50 | 1423 | preempt_enable_notrace(); |
769b0441 FW |
1424 | unpause_graph_tracing(); |
1425 | ||
1426 | return len; | |
1427 | } | |
48ead020 FW |
1428 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1429 | ||
659372d3 SR |
1430 | int trace_array_printk(struct trace_array *tr, |
1431 | unsigned long ip, const char *fmt, ...) | |
1432 | { | |
1433 | int ret; | |
1434 | va_list ap; | |
1435 | ||
1436 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1437 | return 0; | |
1438 | ||
1439 | va_start(ap, fmt); | |
1440 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
1441 | va_end(ap); | |
1442 | return ret; | |
1443 | } | |
1444 | ||
1445 | int trace_array_vprintk(struct trace_array *tr, | |
1446 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 1447 | { |
edc35bd7 | 1448 | static arch_spinlock_t trace_buf_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
48ead020 FW |
1449 | static char trace_buf[TRACE_BUF_SIZE]; |
1450 | ||
e1112b4d | 1451 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1452 | struct ring_buffer_event *event; |
e77405ad | 1453 | struct ring_buffer *buffer; |
48ead020 FW |
1454 | struct trace_array_cpu *data; |
1455 | int cpu, len = 0, size, pc; | |
1456 | struct print_entry *entry; | |
1457 | unsigned long irq_flags; | |
3189cdb3 | 1458 | int disable; |
48ead020 FW |
1459 | |
1460 | if (tracing_disabled || tracing_selftest_running) | |
1461 | return 0; | |
1462 | ||
1463 | pc = preempt_count(); | |
1464 | preempt_disable_notrace(); | |
1465 | cpu = raw_smp_processor_id(); | |
1466 | data = tr->data[cpu]; | |
1467 | ||
3189cdb3 SR |
1468 | disable = atomic_inc_return(&data->disabled); |
1469 | if (unlikely(disable != 1)) | |
48ead020 FW |
1470 | goto out; |
1471 | ||
1472 | pause_graph_tracing(); | |
1473 | raw_local_irq_save(irq_flags); | |
0199c4e6 | 1474 | arch_spin_lock(&trace_buf_lock); |
f2942487 | 1475 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
48ead020 FW |
1476 | |
1477 | size = sizeof(*entry) + len + 1; | |
e77405ad SR |
1478 | buffer = tr->buffer; |
1479 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
1480 | irq_flags, pc); | |
48ead020 FW |
1481 | if (!event) |
1482 | goto out_unlock; | |
1483 | entry = ring_buffer_event_data(event); | |
c13d2f7c | 1484 | entry->ip = ip; |
48ead020 FW |
1485 | |
1486 | memcpy(&entry->buf, trace_buf, len); | |
c13d2f7c | 1487 | entry->buf[len] = '\0'; |
d931369b | 1488 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1489 | ring_buffer_unlock_commit(buffer, event); |
d931369b SR |
1490 | ftrace_trace_stack(buffer, irq_flags, 6, pc); |
1491 | } | |
48ead020 FW |
1492 | |
1493 | out_unlock: | |
0199c4e6 | 1494 | arch_spin_unlock(&trace_buf_lock); |
48ead020 FW |
1495 | raw_local_irq_restore(irq_flags); |
1496 | unpause_graph_tracing(); | |
1497 | out: | |
3189cdb3 | 1498 | atomic_dec_return(&data->disabled); |
48ead020 FW |
1499 | preempt_enable_notrace(); |
1500 | ||
1501 | return len; | |
1502 | } | |
659372d3 SR |
1503 | |
1504 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) | |
1505 | { | |
a813a159 | 1506 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 1507 | } |
769b0441 FW |
1508 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1509 | ||
e2ac8ef5 | 1510 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1511 | { |
d769041f SR |
1512 | /* Don't allow ftrace to trace into the ring buffers */ |
1513 | ftrace_disable_cpu(); | |
1514 | ||
5a90f577 | 1515 | iter->idx++; |
d769041f SR |
1516 | if (iter->buffer_iter[iter->cpu]) |
1517 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1518 | ||
1519 | ftrace_enable_cpu(); | |
5a90f577 SR |
1520 | } |
1521 | ||
e309b41d | 1522 | static struct trace_entry * |
bc21b478 SR |
1523 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
1524 | unsigned long *lost_events) | |
dd0e545f | 1525 | { |
3928a8a2 SR |
1526 | struct ring_buffer_event *event; |
1527 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1528 | |
d769041f SR |
1529 | /* Don't allow ftrace to trace into the ring buffers */ |
1530 | ftrace_disable_cpu(); | |
1531 | ||
1532 | if (buf_iter) | |
1533 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1534 | else | |
bc21b478 SR |
1535 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts, |
1536 | lost_events); | |
d769041f SR |
1537 | |
1538 | ftrace_enable_cpu(); | |
1539 | ||
3928a8a2 | 1540 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1541 | } |
d769041f | 1542 | |
dd0e545f | 1543 | static struct trace_entry * |
bc21b478 SR |
1544 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
1545 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 1546 | { |
3928a8a2 | 1547 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1548 | struct trace_entry *ent, *next = NULL; |
aa27497c | 1549 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 1550 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1551 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1552 | int next_cpu = -1; |
1553 | int cpu; | |
1554 | ||
b04cc6b1 FW |
1555 | /* |
1556 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1557 | * all cpu and peek directly. | |
1558 | */ | |
1559 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1560 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1561 | return NULL; | |
bc21b478 | 1562 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
1563 | if (ent_cpu) |
1564 | *ent_cpu = cpu_file; | |
1565 | ||
1566 | return ent; | |
1567 | } | |
1568 | ||
ab46428c | 1569 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1570 | |
3928a8a2 SR |
1571 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1572 | continue; | |
dd0e545f | 1573 | |
bc21b478 | 1574 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 1575 | |
cdd31cd2 IM |
1576 | /* |
1577 | * Pick the entry with the smallest timestamp: | |
1578 | */ | |
3928a8a2 | 1579 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1580 | next = ent; |
1581 | next_cpu = cpu; | |
3928a8a2 | 1582 | next_ts = ts; |
bc21b478 | 1583 | next_lost = lost_events; |
bc0c38d1 SR |
1584 | } |
1585 | } | |
1586 | ||
1587 | if (ent_cpu) | |
1588 | *ent_cpu = next_cpu; | |
1589 | ||
3928a8a2 SR |
1590 | if (ent_ts) |
1591 | *ent_ts = next_ts; | |
1592 | ||
bc21b478 SR |
1593 | if (missing_events) |
1594 | *missing_events = next_lost; | |
1595 | ||
bc0c38d1 SR |
1596 | return next; |
1597 | } | |
1598 | ||
dd0e545f | 1599 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1600 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1601 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1602 | { |
bc21b478 | 1603 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
1604 | } |
1605 | ||
1606 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 1607 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 1608 | { |
bc21b478 SR |
1609 | iter->ent = __find_next_entry(iter, &iter->cpu, |
1610 | &iter->lost_events, &iter->ts); | |
dd0e545f | 1611 | |
3928a8a2 | 1612 | if (iter->ent) |
e2ac8ef5 | 1613 | trace_iterator_increment(iter); |
dd0e545f | 1614 | |
3928a8a2 | 1615 | return iter->ent ? iter : NULL; |
b3806b43 | 1616 | } |
bc0c38d1 | 1617 | |
e309b41d | 1618 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1619 | { |
d769041f SR |
1620 | /* Don't allow ftrace to trace into the ring buffers */ |
1621 | ftrace_disable_cpu(); | |
bc21b478 SR |
1622 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts, |
1623 | &iter->lost_events); | |
d769041f | 1624 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1625 | } |
1626 | ||
e309b41d | 1627 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1628 | { |
1629 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1630 | int i = (int)*pos; |
4e3c3333 | 1631 | void *ent; |
bc0c38d1 | 1632 | |
a63ce5b3 SR |
1633 | WARN_ON_ONCE(iter->leftover); |
1634 | ||
bc0c38d1 SR |
1635 | (*pos)++; |
1636 | ||
1637 | /* can't go backwards */ | |
1638 | if (iter->idx > i) | |
1639 | return NULL; | |
1640 | ||
1641 | if (iter->idx < 0) | |
955b61e5 | 1642 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1643 | else |
1644 | ent = iter; | |
1645 | ||
1646 | while (ent && iter->idx < i) | |
955b61e5 | 1647 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1648 | |
1649 | iter->pos = *pos; | |
1650 | ||
bc0c38d1 SR |
1651 | return ent; |
1652 | } | |
1653 | ||
955b61e5 | 1654 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 SR |
1655 | { |
1656 | struct trace_array *tr = iter->tr; | |
1657 | struct ring_buffer_event *event; | |
1658 | struct ring_buffer_iter *buf_iter; | |
1659 | unsigned long entries = 0; | |
1660 | u64 ts; | |
1661 | ||
1662 | tr->data[cpu]->skipped_entries = 0; | |
1663 | ||
1664 | if (!iter->buffer_iter[cpu]) | |
1665 | return; | |
1666 | ||
1667 | buf_iter = iter->buffer_iter[cpu]; | |
1668 | ring_buffer_iter_reset(buf_iter); | |
1669 | ||
1670 | /* | |
1671 | * We could have the case with the max latency tracers | |
1672 | * that a reset never took place on a cpu. This is evident | |
1673 | * by the timestamp being before the start of the buffer. | |
1674 | */ | |
1675 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
1676 | if (ts >= iter->tr->time_start) | |
1677 | break; | |
1678 | entries++; | |
1679 | ring_buffer_read(buf_iter, NULL); | |
1680 | } | |
1681 | ||
1682 | tr->data[cpu]->skipped_entries = entries; | |
1683 | } | |
1684 | ||
d7350c3f | 1685 | /* |
d7350c3f FW |
1686 | * The current tracer is copied to avoid a global locking |
1687 | * all around. | |
1688 | */ | |
bc0c38d1 SR |
1689 | static void *s_start(struct seq_file *m, loff_t *pos) |
1690 | { | |
1691 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1692 | static struct tracer *old_tracer; |
b04cc6b1 | 1693 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1694 | void *p = NULL; |
1695 | loff_t l = 0; | |
3928a8a2 | 1696 | int cpu; |
bc0c38d1 | 1697 | |
d7350c3f | 1698 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1699 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1700 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1701 | old_tracer = current_trace; | |
1702 | *iter->trace = *current_trace; | |
d15f57f2 | 1703 | } |
d7350c3f | 1704 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1705 | |
1706 | atomic_inc(&trace_record_cmdline_disabled); | |
1707 | ||
bc0c38d1 SR |
1708 | if (*pos != iter->pos) { |
1709 | iter->ent = NULL; | |
1710 | iter->cpu = 0; | |
1711 | iter->idx = -1; | |
1712 | ||
d769041f SR |
1713 | ftrace_disable_cpu(); |
1714 | ||
b04cc6b1 FW |
1715 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1716 | for_each_tracing_cpu(cpu) | |
2f26ebd5 | 1717 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 1718 | } else |
2f26ebd5 | 1719 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 1720 | |
d769041f SR |
1721 | ftrace_enable_cpu(); |
1722 | ||
ac91d854 | 1723 | iter->leftover = 0; |
bc0c38d1 SR |
1724 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1725 | ; | |
1726 | ||
1727 | } else { | |
a63ce5b3 SR |
1728 | /* |
1729 | * If we overflowed the seq_file before, then we want | |
1730 | * to just reuse the trace_seq buffer again. | |
1731 | */ | |
1732 | if (iter->leftover) | |
1733 | p = iter; | |
1734 | else { | |
1735 | l = *pos - 1; | |
1736 | p = s_next(m, p, &l); | |
1737 | } | |
bc0c38d1 SR |
1738 | } |
1739 | ||
4f535968 | 1740 | trace_event_read_lock(); |
7e53bd42 | 1741 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
1742 | return p; |
1743 | } | |
1744 | ||
1745 | static void s_stop(struct seq_file *m, void *p) | |
1746 | { | |
7e53bd42 LJ |
1747 | struct trace_iterator *iter = m->private; |
1748 | ||
bc0c38d1 | 1749 | atomic_dec(&trace_record_cmdline_disabled); |
7e53bd42 | 1750 | trace_access_unlock(iter->cpu_file); |
4f535968 | 1751 | trace_event_read_unlock(); |
bc0c38d1 SR |
1752 | } |
1753 | ||
e309b41d | 1754 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1755 | { |
a6168353 ME |
1756 | seq_puts(m, "# _------=> CPU# \n"); |
1757 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1758 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1759 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1760 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
1761 | seq_puts(m, "# |||| / delay \n"); |
1762 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1763 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1764 | } |
1765 | ||
e309b41d | 1766 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1767 | { |
a6168353 ME |
1768 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1769 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1770 | } |
1771 | ||
1772 | ||
62b915f1 | 1773 | void |
bc0c38d1 SR |
1774 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1775 | { | |
1776 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1777 | struct trace_array *tr = iter->tr; | |
1778 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1779 | struct tracer *type = current_trace; | |
2f26ebd5 SR |
1780 | unsigned long entries = 0; |
1781 | unsigned long total = 0; | |
1782 | unsigned long count; | |
bc0c38d1 | 1783 | const char *name = "preemption"; |
2f26ebd5 | 1784 | int cpu; |
bc0c38d1 SR |
1785 | |
1786 | if (type) | |
1787 | name = type->name; | |
1788 | ||
2f26ebd5 SR |
1789 | |
1790 | for_each_tracing_cpu(cpu) { | |
1791 | count = ring_buffer_entries_cpu(tr->buffer, cpu); | |
1792 | /* | |
1793 | * If this buffer has skipped entries, then we hold all | |
1794 | * entries for the trace and we need to ignore the | |
1795 | * ones before the time stamp. | |
1796 | */ | |
1797 | if (tr->data[cpu]->skipped_entries) { | |
1798 | count -= tr->data[cpu]->skipped_entries; | |
1799 | /* total is the same as the entries */ | |
1800 | total += count; | |
1801 | } else | |
1802 | total += count + | |
1803 | ring_buffer_overrun_cpu(tr->buffer, cpu); | |
1804 | entries += count; | |
1805 | } | |
bc0c38d1 | 1806 | |
888b55dc | 1807 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1808 | name, UTS_RELEASE); |
888b55dc | 1809 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1810 | "---------------------------------\n"); |
888b55dc | 1811 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1812 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1813 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1814 | entries, |
4c11d7ae | 1815 | total, |
bc0c38d1 SR |
1816 | tr->cpu, |
1817 | #if defined(CONFIG_PREEMPT_NONE) | |
1818 | "server", | |
1819 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1820 | "desktop", | |
b5c21b45 | 1821 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1822 | "preempt", |
1823 | #else | |
1824 | "unknown", | |
1825 | #endif | |
1826 | /* These are reserved for later use */ | |
1827 | 0, 0, 0, 0); | |
1828 | #ifdef CONFIG_SMP | |
1829 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1830 | #else | |
1831 | seq_puts(m, ")\n"); | |
1832 | #endif | |
888b55dc KM |
1833 | seq_puts(m, "# -----------------\n"); |
1834 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1835 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1836 | data->comm, data->pid, data->uid, data->nice, | |
1837 | data->policy, data->rt_priority); | |
888b55dc | 1838 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1839 | |
1840 | if (data->critical_start) { | |
888b55dc | 1841 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1842 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1843 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1844 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1845 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1846 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 1847 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
1848 | } |
1849 | ||
888b55dc | 1850 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1851 | } |
1852 | ||
a309720c SR |
1853 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1854 | { | |
1855 | struct trace_seq *s = &iter->seq; | |
1856 | ||
12ef7d44 SR |
1857 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1858 | return; | |
1859 | ||
1860 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1861 | return; | |
1862 | ||
4462344e | 1863 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1864 | return; |
1865 | ||
2f26ebd5 SR |
1866 | if (iter->tr->data[iter->cpu]->skipped_entries) |
1867 | return; | |
1868 | ||
4462344e | 1869 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1870 | |
1871 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1872 | if (iter->idx > 1) | |
1873 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1874 | iter->cpu); | |
a309720c SR |
1875 | } |
1876 | ||
2c4f035f | 1877 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1878 | { |
214023c3 | 1879 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1880 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1881 | struct trace_entry *entry; |
f633cef0 | 1882 | struct trace_event *event; |
bc0c38d1 | 1883 | |
4e3c3333 | 1884 | entry = iter->ent; |
dd0e545f | 1885 | |
a309720c SR |
1886 | test_cpu_buff_start(iter); |
1887 | ||
c4a8e8be | 1888 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1889 | |
c4a8e8be | 1890 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1891 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1892 | if (!trace_print_lat_context(iter)) | |
1893 | goto partial; | |
1894 | } else { | |
1895 | if (!trace_print_context(iter)) | |
1896 | goto partial; | |
1897 | } | |
c4a8e8be | 1898 | } |
bc0c38d1 | 1899 | |
268ccda0 | 1900 | if (event) |
a9a57763 | 1901 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
1902 | |
1903 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1904 | goto partial; | |
02b67518 | 1905 | |
2c4f035f | 1906 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1907 | partial: |
1908 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1909 | } |
1910 | ||
2c4f035f | 1911 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1912 | { |
1913 | struct trace_seq *s = &iter->seq; | |
1914 | struct trace_entry *entry; | |
f633cef0 | 1915 | struct trace_event *event; |
f9896bf3 IM |
1916 | |
1917 | entry = iter->ent; | |
dd0e545f | 1918 | |
c4a8e8be | 1919 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1920 | if (!trace_seq_printf(s, "%d %d %llu ", |
1921 | entry->pid, iter->cpu, iter->ts)) | |
1922 | goto partial; | |
c4a8e8be | 1923 | } |
f9896bf3 | 1924 | |
f633cef0 | 1925 | event = ftrace_find_event(entry->type); |
268ccda0 | 1926 | if (event) |
a9a57763 | 1927 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
1928 | |
1929 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1930 | goto partial; | |
777e208d | 1931 | |
2c4f035f | 1932 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1933 | partial: |
1934 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1935 | } |
1936 | ||
2c4f035f | 1937 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1938 | { |
1939 | struct trace_seq *s = &iter->seq; | |
1940 | unsigned char newline = '\n'; | |
1941 | struct trace_entry *entry; | |
f633cef0 | 1942 | struct trace_event *event; |
5e3ca0ec IM |
1943 | |
1944 | entry = iter->ent; | |
dd0e545f | 1945 | |
c4a8e8be FW |
1946 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1947 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1948 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1949 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1950 | } | |
5e3ca0ec | 1951 | |
f633cef0 | 1952 | event = ftrace_find_event(entry->type); |
268ccda0 | 1953 | if (event) { |
a9a57763 | 1954 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
1955 | if (ret != TRACE_TYPE_HANDLED) |
1956 | return ret; | |
1957 | } | |
7104f300 | 1958 | |
5e3ca0ec IM |
1959 | SEQ_PUT_FIELD_RET(s, newline); |
1960 | ||
2c4f035f | 1961 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1962 | } |
1963 | ||
2c4f035f | 1964 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1965 | { |
1966 | struct trace_seq *s = &iter->seq; | |
1967 | struct trace_entry *entry; | |
f633cef0 | 1968 | struct trace_event *event; |
cb0f12aa IM |
1969 | |
1970 | entry = iter->ent; | |
dd0e545f | 1971 | |
c4a8e8be FW |
1972 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1973 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1974 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1975 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1976 | } | |
cb0f12aa | 1977 | |
f633cef0 | 1978 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
1979 | return event ? event->funcs->binary(iter, 0, event) : |
1980 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
1981 | } |
1982 | ||
62b915f1 | 1983 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 1984 | { |
bc0c38d1 SR |
1985 | int cpu; |
1986 | ||
9aba60fe SR |
1987 | /* If we are looking at one CPU buffer, only check that one */ |
1988 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1989 | cpu = iter->cpu_file; | |
1990 | if (iter->buffer_iter[cpu]) { | |
1991 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1992 | return 0; | |
1993 | } else { | |
1994 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1995 | return 0; | |
1996 | } | |
1997 | return 1; | |
1998 | } | |
1999 | ||
ab46428c | 2000 | for_each_tracing_cpu(cpu) { |
d769041f SR |
2001 | if (iter->buffer_iter[cpu]) { |
2002 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
2003 | return 0; | |
2004 | } else { | |
2005 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
2006 | return 0; | |
2007 | } | |
bc0c38d1 | 2008 | } |
d769041f | 2009 | |
797d3712 | 2010 | return 1; |
bc0c38d1 SR |
2011 | } |
2012 | ||
4f535968 | 2013 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2014 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2015 | { |
2c4f035f FW |
2016 | enum print_line_t ret; |
2017 | ||
ee5e51f5 JO |
2018 | if (iter->lost_events && |
2019 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2020 | iter->cpu, iter->lost_events)) | |
2021 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2022 | |
2c4f035f FW |
2023 | if (iter->trace && iter->trace->print_line) { |
2024 | ret = iter->trace->print_line(iter); | |
2025 | if (ret != TRACE_TYPE_UNHANDLED) | |
2026 | return ret; | |
2027 | } | |
72829bc3 | 2028 | |
48ead020 FW |
2029 | if (iter->ent->type == TRACE_BPRINT && |
2030 | trace_flags & TRACE_ITER_PRINTK && | |
2031 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2032 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2033 | |
66896a85 FW |
2034 | if (iter->ent->type == TRACE_PRINT && |
2035 | trace_flags & TRACE_ITER_PRINTK && | |
2036 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2037 | return trace_print_printk_msg_only(iter); |
66896a85 | 2038 | |
cb0f12aa IM |
2039 | if (trace_flags & TRACE_ITER_BIN) |
2040 | return print_bin_fmt(iter); | |
2041 | ||
5e3ca0ec IM |
2042 | if (trace_flags & TRACE_ITER_HEX) |
2043 | return print_hex_fmt(iter); | |
2044 | ||
f9896bf3 IM |
2045 | if (trace_flags & TRACE_ITER_RAW) |
2046 | return print_raw_fmt(iter); | |
2047 | ||
f9896bf3 IM |
2048 | return print_trace_fmt(iter); |
2049 | } | |
2050 | ||
62b915f1 JO |
2051 | void trace_default_header(struct seq_file *m) |
2052 | { | |
2053 | struct trace_iterator *iter = m->private; | |
2054 | ||
2055 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
2056 | /* print nothing if the buffers are empty */ | |
2057 | if (trace_empty(iter)) | |
2058 | return; | |
2059 | print_trace_header(m, iter); | |
2060 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2061 | print_lat_help_header(m); | |
2062 | } else { | |
2063 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2064 | print_func_help_header(m); | |
2065 | } | |
2066 | } | |
2067 | ||
bc0c38d1 SR |
2068 | static int s_show(struct seq_file *m, void *v) |
2069 | { | |
2070 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2071 | int ret; |
bc0c38d1 SR |
2072 | |
2073 | if (iter->ent == NULL) { | |
2074 | if (iter->tr) { | |
2075 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2076 | seq_puts(m, "#\n"); | |
2077 | } | |
8bba1bf5 MM |
2078 | if (iter->trace && iter->trace->print_header) |
2079 | iter->trace->print_header(m); | |
62b915f1 JO |
2080 | else |
2081 | trace_default_header(m); | |
2082 | ||
a63ce5b3 SR |
2083 | } else if (iter->leftover) { |
2084 | /* | |
2085 | * If we filled the seq_file buffer earlier, we | |
2086 | * want to just show it now. | |
2087 | */ | |
2088 | ret = trace_print_seq(m, &iter->seq); | |
2089 | ||
2090 | /* ret should this time be zero, but you never know */ | |
2091 | iter->leftover = ret; | |
2092 | ||
bc0c38d1 | 2093 | } else { |
f9896bf3 | 2094 | print_trace_line(iter); |
a63ce5b3 SR |
2095 | ret = trace_print_seq(m, &iter->seq); |
2096 | /* | |
2097 | * If we overflow the seq_file buffer, then it will | |
2098 | * ask us for this data again at start up. | |
2099 | * Use that instead. | |
2100 | * ret is 0 if seq_file write succeeded. | |
2101 | * -1 otherwise. | |
2102 | */ | |
2103 | iter->leftover = ret; | |
bc0c38d1 SR |
2104 | } |
2105 | ||
2106 | return 0; | |
2107 | } | |
2108 | ||
88e9d34c | 2109 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2110 | .start = s_start, |
2111 | .next = s_next, | |
2112 | .stop = s_stop, | |
2113 | .show = s_show, | |
bc0c38d1 SR |
2114 | }; |
2115 | ||
e309b41d | 2116 | static struct trace_iterator * |
85a2f9b4 | 2117 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 2118 | { |
b04cc6b1 | 2119 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 2120 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 2121 | struct trace_iterator *iter; |
3928a8a2 | 2122 | struct seq_file *m; |
85a2f9b4 | 2123 | int cpu, ret; |
bc0c38d1 | 2124 | |
85a2f9b4 SR |
2125 | if (tracing_disabled) |
2126 | return ERR_PTR(-ENODEV); | |
60a11774 | 2127 | |
bc0c38d1 | 2128 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
2129 | if (!iter) |
2130 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2131 | |
d7350c3f FW |
2132 | /* |
2133 | * We make a copy of the current tracer to avoid concurrent | |
2134 | * changes on it while we are reading. | |
2135 | */ | |
bc0c38d1 | 2136 | mutex_lock(&trace_types_lock); |
d7350c3f | 2137 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2138 | if (!iter->trace) |
d7350c3f | 2139 | goto fail; |
85a2f9b4 | 2140 | |
d7350c3f FW |
2141 | if (current_trace) |
2142 | *iter->trace = *current_trace; | |
2143 | ||
79f55997 | 2144 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2145 | goto fail; |
2146 | ||
bc0c38d1 SR |
2147 | if (current_trace && current_trace->print_max) |
2148 | iter->tr = &max_tr; | |
2149 | else | |
b04cc6b1 | 2150 | iter->tr = &global_trace; |
bc0c38d1 | 2151 | iter->pos = -1; |
d7350c3f | 2152 | mutex_init(&iter->mutex); |
b04cc6b1 | 2153 | iter->cpu_file = cpu_file; |
bc0c38d1 | 2154 | |
8bba1bf5 MM |
2155 | /* Notify the tracer early; before we stop tracing. */ |
2156 | if (iter->trace && iter->trace->open) | |
a93751ca | 2157 | iter->trace->open(iter); |
8bba1bf5 | 2158 | |
12ef7d44 SR |
2159 | /* Annotate start of buffers if we had overruns */ |
2160 | if (ring_buffer_overruns(iter->tr->buffer)) | |
2161 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
2162 | ||
2f26ebd5 SR |
2163 | /* stop the trace while dumping */ |
2164 | tracing_stop(); | |
2165 | ||
b04cc6b1 FW |
2166 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
2167 | for_each_tracing_cpu(cpu) { | |
b04cc6b1 | 2168 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2169 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2170 | } | |
2171 | ring_buffer_read_prepare_sync(); | |
2172 | for_each_tracing_cpu(cpu) { | |
2173 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2174 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2175 | } |
2176 | } else { | |
2177 | cpu = iter->cpu_file; | |
3928a8a2 | 2178 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2179 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2180 | ring_buffer_read_prepare_sync(); | |
2181 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2182 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2183 | } |
2184 | ||
85a2f9b4 SR |
2185 | ret = seq_open(file, &tracer_seq_ops); |
2186 | if (ret < 0) { | |
2187 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 2188 | goto fail_buffer; |
85a2f9b4 | 2189 | } |
bc0c38d1 | 2190 | |
3928a8a2 SR |
2191 | m = file->private_data; |
2192 | m->private = iter; | |
bc0c38d1 | 2193 | |
bc0c38d1 SR |
2194 | mutex_unlock(&trace_types_lock); |
2195 | ||
bc0c38d1 | 2196 | return iter; |
3928a8a2 SR |
2197 | |
2198 | fail_buffer: | |
2199 | for_each_tracing_cpu(cpu) { | |
2200 | if (iter->buffer_iter[cpu]) | |
2201 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2202 | } | |
b0dfa978 | 2203 | free_cpumask_var(iter->started); |
2f26ebd5 | 2204 | tracing_start(); |
d7350c3f | 2205 | fail: |
3928a8a2 | 2206 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2207 | kfree(iter->trace); |
0bb943c7 | 2208 | kfree(iter); |
3928a8a2 | 2209 | |
85a2f9b4 | 2210 | return fail_ret; |
bc0c38d1 SR |
2211 | } |
2212 | ||
2213 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2214 | { | |
60a11774 SR |
2215 | if (tracing_disabled) |
2216 | return -ENODEV; | |
2217 | ||
bc0c38d1 SR |
2218 | filp->private_data = inode->i_private; |
2219 | return 0; | |
2220 | } | |
2221 | ||
4fd27358 | 2222 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 2223 | { |
907f2784 | 2224 | struct seq_file *m = file->private_data; |
4acd4d00 | 2225 | struct trace_iterator *iter; |
3928a8a2 | 2226 | int cpu; |
bc0c38d1 | 2227 | |
4acd4d00 SR |
2228 | if (!(file->f_mode & FMODE_READ)) |
2229 | return 0; | |
2230 | ||
2231 | iter = m->private; | |
2232 | ||
bc0c38d1 | 2233 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
2234 | for_each_tracing_cpu(cpu) { |
2235 | if (iter->buffer_iter[cpu]) | |
2236 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2237 | } | |
2238 | ||
bc0c38d1 SR |
2239 | if (iter->trace && iter->trace->close) |
2240 | iter->trace->close(iter); | |
2241 | ||
2242 | /* reenable tracing if it was previously enabled */ | |
9036990d | 2243 | tracing_start(); |
bc0c38d1 SR |
2244 | mutex_unlock(&trace_types_lock); |
2245 | ||
2246 | seq_release(inode, file); | |
d7350c3f | 2247 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2248 | free_cpumask_var(iter->started); |
d7350c3f | 2249 | kfree(iter->trace); |
bc0c38d1 SR |
2250 | kfree(iter); |
2251 | return 0; | |
2252 | } | |
2253 | ||
2254 | static int tracing_open(struct inode *inode, struct file *file) | |
2255 | { | |
85a2f9b4 SR |
2256 | struct trace_iterator *iter; |
2257 | int ret = 0; | |
bc0c38d1 | 2258 | |
4acd4d00 SR |
2259 | /* If this file was open for write, then erase contents */ |
2260 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2261 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 2262 | long cpu = (long) inode->i_private; |
bc0c38d1 | 2263 | |
4acd4d00 SR |
2264 | if (cpu == TRACE_PIPE_ALL_CPU) |
2265 | tracing_reset_online_cpus(&global_trace); | |
2266 | else | |
2267 | tracing_reset(&global_trace, cpu); | |
2268 | } | |
bc0c38d1 | 2269 | |
4acd4d00 SR |
2270 | if (file->f_mode & FMODE_READ) { |
2271 | iter = __tracing_open(inode, file); | |
2272 | if (IS_ERR(iter)) | |
2273 | ret = PTR_ERR(iter); | |
2274 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2275 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2276 | } | |
bc0c38d1 SR |
2277 | return ret; |
2278 | } | |
2279 | ||
e309b41d | 2280 | static void * |
bc0c38d1 SR |
2281 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2282 | { | |
f129e965 | 2283 | struct tracer *t = v; |
bc0c38d1 SR |
2284 | |
2285 | (*pos)++; | |
2286 | ||
2287 | if (t) | |
2288 | t = t->next; | |
2289 | ||
bc0c38d1 SR |
2290 | return t; |
2291 | } | |
2292 | ||
2293 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2294 | { | |
f129e965 | 2295 | struct tracer *t; |
bc0c38d1 SR |
2296 | loff_t l = 0; |
2297 | ||
2298 | mutex_lock(&trace_types_lock); | |
f129e965 | 2299 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2300 | ; |
2301 | ||
2302 | return t; | |
2303 | } | |
2304 | ||
2305 | static void t_stop(struct seq_file *m, void *p) | |
2306 | { | |
2307 | mutex_unlock(&trace_types_lock); | |
2308 | } | |
2309 | ||
2310 | static int t_show(struct seq_file *m, void *v) | |
2311 | { | |
2312 | struct tracer *t = v; | |
2313 | ||
2314 | if (!t) | |
2315 | return 0; | |
2316 | ||
2317 | seq_printf(m, "%s", t->name); | |
2318 | if (t->next) | |
2319 | seq_putc(m, ' '); | |
2320 | else | |
2321 | seq_putc(m, '\n'); | |
2322 | ||
2323 | return 0; | |
2324 | } | |
2325 | ||
88e9d34c | 2326 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
2327 | .start = t_start, |
2328 | .next = t_next, | |
2329 | .stop = t_stop, | |
2330 | .show = t_show, | |
bc0c38d1 SR |
2331 | }; |
2332 | ||
2333 | static int show_traces_open(struct inode *inode, struct file *file) | |
2334 | { | |
60a11774 SR |
2335 | if (tracing_disabled) |
2336 | return -ENODEV; | |
2337 | ||
f129e965 | 2338 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2339 | } |
2340 | ||
4acd4d00 SR |
2341 | static ssize_t |
2342 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2343 | size_t count, loff_t *ppos) | |
2344 | { | |
2345 | return count; | |
2346 | } | |
2347 | ||
364829b1 SP |
2348 | static loff_t tracing_seek(struct file *file, loff_t offset, int origin) |
2349 | { | |
2350 | if (file->f_mode & FMODE_READ) | |
2351 | return seq_lseek(file, offset, origin); | |
2352 | else | |
2353 | return 0; | |
2354 | } | |
2355 | ||
5e2336a0 | 2356 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2357 | .open = tracing_open, |
2358 | .read = seq_read, | |
4acd4d00 | 2359 | .write = tracing_write_stub, |
364829b1 | 2360 | .llseek = tracing_seek, |
4bf39a94 | 2361 | .release = tracing_release, |
bc0c38d1 SR |
2362 | }; |
2363 | ||
5e2336a0 | 2364 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2365 | .open = show_traces_open, |
2366 | .read = seq_read, | |
2367 | .release = seq_release, | |
b444786f | 2368 | .llseek = seq_lseek, |
c7078de1 IM |
2369 | }; |
2370 | ||
36dfe925 IM |
2371 | /* |
2372 | * Only trace on a CPU if the bitmask is set: | |
2373 | */ | |
9e01c1b7 | 2374 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2375 | |
2376 | /* | |
2377 | * The tracer itself will not take this lock, but still we want | |
2378 | * to provide a consistent cpumask to user-space: | |
2379 | */ | |
2380 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2381 | ||
2382 | /* | |
2383 | * Temporary storage for the character representation of the | |
2384 | * CPU bitmask (and one more byte for the newline): | |
2385 | */ | |
2386 | static char mask_str[NR_CPUS + 1]; | |
2387 | ||
c7078de1 IM |
2388 | static ssize_t |
2389 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2390 | size_t count, loff_t *ppos) | |
2391 | { | |
36dfe925 | 2392 | int len; |
c7078de1 IM |
2393 | |
2394 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2395 | |
9e01c1b7 | 2396 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2397 | if (count - len < 2) { |
2398 | count = -EINVAL; | |
2399 | goto out_err; | |
2400 | } | |
2401 | len += sprintf(mask_str + len, "\n"); | |
2402 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2403 | ||
2404 | out_err: | |
c7078de1 IM |
2405 | mutex_unlock(&tracing_cpumask_update_lock); |
2406 | ||
2407 | return count; | |
2408 | } | |
2409 | ||
2410 | static ssize_t | |
2411 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2412 | size_t count, loff_t *ppos) | |
2413 | { | |
36dfe925 | 2414 | int err, cpu; |
9e01c1b7 RR |
2415 | cpumask_var_t tracing_cpumask_new; |
2416 | ||
2417 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2418 | return -ENOMEM; | |
c7078de1 | 2419 | |
9e01c1b7 | 2420 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2421 | if (err) |
36dfe925 IM |
2422 | goto err_unlock; |
2423 | ||
215368e8 LZ |
2424 | mutex_lock(&tracing_cpumask_update_lock); |
2425 | ||
a5e25883 | 2426 | local_irq_disable(); |
0199c4e6 | 2427 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 2428 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2429 | /* |
2430 | * Increase/decrease the disabled counter if we are | |
2431 | * about to flip a bit in the cpumask: | |
2432 | */ | |
9e01c1b7 RR |
2433 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2434 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2435 | atomic_inc(&global_trace.data[cpu]->disabled); |
2436 | } | |
9e01c1b7 RR |
2437 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2438 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2439 | atomic_dec(&global_trace.data[cpu]->disabled); |
2440 | } | |
2441 | } | |
0199c4e6 | 2442 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2443 | local_irq_enable(); |
36dfe925 | 2444 | |
9e01c1b7 | 2445 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2446 | |
2447 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2448 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2449 | |
2450 | return count; | |
36dfe925 IM |
2451 | |
2452 | err_unlock: | |
215368e8 | 2453 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2454 | |
2455 | return err; | |
c7078de1 IM |
2456 | } |
2457 | ||
5e2336a0 | 2458 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2459 | .open = tracing_open_generic, |
2460 | .read = tracing_cpumask_read, | |
2461 | .write = tracing_cpumask_write, | |
b444786f | 2462 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
2463 | }; |
2464 | ||
fdb372ed | 2465 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 2466 | { |
d8e83d26 SR |
2467 | struct tracer_opt *trace_opts; |
2468 | u32 tracer_flags; | |
d8e83d26 | 2469 | int i; |
adf9f195 | 2470 | |
d8e83d26 SR |
2471 | mutex_lock(&trace_types_lock); |
2472 | tracer_flags = current_trace->flags->val; | |
2473 | trace_opts = current_trace->flags->opts; | |
2474 | ||
bc0c38d1 SR |
2475 | for (i = 0; trace_options[i]; i++) { |
2476 | if (trace_flags & (1 << i)) | |
fdb372ed | 2477 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 2478 | else |
fdb372ed | 2479 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2480 | } |
2481 | ||
adf9f195 FW |
2482 | for (i = 0; trace_opts[i].name; i++) { |
2483 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 2484 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 2485 | else |
fdb372ed | 2486 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 2487 | } |
d8e83d26 | 2488 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2489 | |
fdb372ed | 2490 | return 0; |
bc0c38d1 | 2491 | } |
bc0c38d1 | 2492 | |
8d18eaaf LZ |
2493 | static int __set_tracer_option(struct tracer *trace, |
2494 | struct tracer_flags *tracer_flags, | |
2495 | struct tracer_opt *opts, int neg) | |
2496 | { | |
2497 | int ret; | |
bc0c38d1 | 2498 | |
8d18eaaf LZ |
2499 | ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); |
2500 | if (ret) | |
2501 | return ret; | |
2502 | ||
2503 | if (neg) | |
2504 | tracer_flags->val &= ~opts->bit; | |
2505 | else | |
2506 | tracer_flags->val |= opts->bit; | |
2507 | return 0; | |
bc0c38d1 SR |
2508 | } |
2509 | ||
adf9f195 FW |
2510 | /* Try to assign a tracer specific option */ |
2511 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2512 | { | |
7770841e | 2513 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 2514 | struct tracer_opt *opts = NULL; |
8d18eaaf | 2515 | int i; |
adf9f195 | 2516 | |
7770841e Z |
2517 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2518 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 2519 | |
8d18eaaf LZ |
2520 | if (strcmp(cmp, opts->name) == 0) |
2521 | return __set_tracer_option(trace, trace->flags, | |
2522 | opts, neg); | |
adf9f195 | 2523 | } |
adf9f195 | 2524 | |
8d18eaaf | 2525 | return -EINVAL; |
adf9f195 FW |
2526 | } |
2527 | ||
af4617bd SR |
2528 | static void set_tracer_flags(unsigned int mask, int enabled) |
2529 | { | |
2530 | /* do nothing if flag is already set */ | |
2531 | if (!!(trace_flags & mask) == !!enabled) | |
2532 | return; | |
2533 | ||
2534 | if (enabled) | |
2535 | trace_flags |= mask; | |
2536 | else | |
2537 | trace_flags &= ~mask; | |
e870e9a1 LZ |
2538 | |
2539 | if (mask == TRACE_ITER_RECORD_CMD) | |
2540 | trace_event_enable_cmd_record(enabled); | |
750912fa DS |
2541 | |
2542 | if (mask == TRACE_ITER_OVERWRITE) | |
2543 | ring_buffer_change_overwrite(global_trace.buffer, enabled); | |
af4617bd SR |
2544 | } |
2545 | ||
bc0c38d1 | 2546 | static ssize_t |
ee6bce52 | 2547 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2548 | size_t cnt, loff_t *ppos) |
2549 | { | |
2550 | char buf[64]; | |
8d18eaaf | 2551 | char *cmp; |
bc0c38d1 | 2552 | int neg = 0; |
adf9f195 | 2553 | int ret; |
bc0c38d1 SR |
2554 | int i; |
2555 | ||
cffae437 SR |
2556 | if (cnt >= sizeof(buf)) |
2557 | return -EINVAL; | |
bc0c38d1 SR |
2558 | |
2559 | if (copy_from_user(&buf, ubuf, cnt)) | |
2560 | return -EFAULT; | |
2561 | ||
2562 | buf[cnt] = 0; | |
8d18eaaf | 2563 | cmp = strstrip(buf); |
bc0c38d1 | 2564 | |
8d18eaaf | 2565 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
2566 | neg = 1; |
2567 | cmp += 2; | |
2568 | } | |
2569 | ||
2570 | for (i = 0; trace_options[i]; i++) { | |
8d18eaaf | 2571 | if (strcmp(cmp, trace_options[i]) == 0) { |
af4617bd | 2572 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2573 | break; |
2574 | } | |
2575 | } | |
adf9f195 FW |
2576 | |
2577 | /* If no option could be set, test the specific tracer options */ | |
2578 | if (!trace_options[i]) { | |
d8e83d26 | 2579 | mutex_lock(&trace_types_lock); |
adf9f195 | 2580 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2581 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2582 | if (ret) |
2583 | return ret; | |
2584 | } | |
bc0c38d1 | 2585 | |
cf8517cf | 2586 | *ppos += cnt; |
bc0c38d1 SR |
2587 | |
2588 | return cnt; | |
2589 | } | |
2590 | ||
fdb372ed LZ |
2591 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
2592 | { | |
2593 | if (tracing_disabled) | |
2594 | return -ENODEV; | |
2595 | return single_open(file, tracing_trace_options_show, NULL); | |
2596 | } | |
2597 | ||
5e2336a0 | 2598 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
2599 | .open = tracing_trace_options_open, |
2600 | .read = seq_read, | |
2601 | .llseek = seq_lseek, | |
2602 | .release = single_release, | |
ee6bce52 | 2603 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
2604 | }; |
2605 | ||
7bd2f24c IM |
2606 | static const char readme_msg[] = |
2607 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2608 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2609 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
bc2b6871 | 2610 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
156f5a78 | 2611 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2612 | "nop\n" |
156f5a78 GL |
2613 | "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" |
2614 | "# cat /sys/kernel/debug/tracing/current_tracer\n" | |
7bd2f24c | 2615 | "sched_switch\n" |
156f5a78 | 2616 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2617 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 GL |
2618 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
2619 | "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
2620 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" | |
2621 | "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
7bd2f24c IM |
2622 | ; |
2623 | ||
2624 | static ssize_t | |
2625 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2626 | size_t cnt, loff_t *ppos) | |
2627 | { | |
2628 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2629 | readme_msg, strlen(readme_msg)); | |
2630 | } | |
2631 | ||
5e2336a0 | 2632 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2633 | .open = tracing_open_generic, |
2634 | .read = tracing_readme_read, | |
b444786f | 2635 | .llseek = generic_file_llseek, |
7bd2f24c IM |
2636 | }; |
2637 | ||
69abe6a5 AP |
2638 | static ssize_t |
2639 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2640 | size_t cnt, loff_t *ppos) | |
2641 | { | |
2642 | char *buf_comm; | |
2643 | char *file_buf; | |
2644 | char *buf; | |
2645 | int len = 0; | |
2646 | int pid; | |
2647 | int i; | |
2648 | ||
2649 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2650 | if (!file_buf) | |
2651 | return -ENOMEM; | |
2652 | ||
2653 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2654 | if (!buf_comm) { | |
2655 | kfree(file_buf); | |
2656 | return -ENOMEM; | |
2657 | } | |
2658 | ||
2659 | buf = file_buf; | |
2660 | ||
2661 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2662 | int r; | |
2663 | ||
2664 | pid = map_cmdline_to_pid[i]; | |
2665 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2666 | continue; | |
2667 | ||
2668 | trace_find_cmdline(pid, buf_comm); | |
2669 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2670 | buf += r; | |
2671 | len += r; | |
2672 | } | |
2673 | ||
2674 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2675 | file_buf, len); | |
2676 | ||
2677 | kfree(file_buf); | |
2678 | kfree(buf_comm); | |
2679 | ||
2680 | return len; | |
2681 | } | |
2682 | ||
2683 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2684 | .open = tracing_open_generic, | |
2685 | .read = tracing_saved_cmdlines_read, | |
b444786f | 2686 | .llseek = generic_file_llseek, |
69abe6a5 AP |
2687 | }; |
2688 | ||
bc0c38d1 SR |
2689 | static ssize_t |
2690 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2691 | size_t cnt, loff_t *ppos) | |
2692 | { | |
bc0c38d1 SR |
2693 | char buf[64]; |
2694 | int r; | |
2695 | ||
9036990d | 2696 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2697 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2698 | } |
2699 | ||
2700 | static ssize_t | |
2701 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2702 | size_t cnt, loff_t *ppos) | |
2703 | { | |
2704 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2705 | char buf[64]; |
5e39841c | 2706 | unsigned long val; |
c6caeeb1 | 2707 | int ret; |
bc0c38d1 | 2708 | |
cffae437 SR |
2709 | if (cnt >= sizeof(buf)) |
2710 | return -EINVAL; | |
bc0c38d1 SR |
2711 | |
2712 | if (copy_from_user(&buf, ubuf, cnt)) | |
2713 | return -EFAULT; | |
2714 | ||
2715 | buf[cnt] = 0; | |
2716 | ||
c6caeeb1 SR |
2717 | ret = strict_strtoul(buf, 10, &val); |
2718 | if (ret < 0) | |
2719 | return ret; | |
bc0c38d1 SR |
2720 | |
2721 | val = !!val; | |
2722 | ||
2723 | mutex_lock(&trace_types_lock); | |
9036990d | 2724 | if (tracer_enabled ^ val) { |
6752ab4a SR |
2725 | |
2726 | /* Only need to warn if this is used to change the state */ | |
2727 | WARN_ONCE(1, "tracing_enabled is deprecated. Use tracing_on"); | |
2728 | ||
9036990d | 2729 | if (val) { |
bc0c38d1 | 2730 | tracer_enabled = 1; |
9036990d SR |
2731 | if (current_trace->start) |
2732 | current_trace->start(tr); | |
2733 | tracing_start(); | |
2734 | } else { | |
bc0c38d1 | 2735 | tracer_enabled = 0; |
9036990d SR |
2736 | tracing_stop(); |
2737 | if (current_trace->stop) | |
2738 | current_trace->stop(tr); | |
2739 | } | |
bc0c38d1 SR |
2740 | } |
2741 | mutex_unlock(&trace_types_lock); | |
2742 | ||
cf8517cf | 2743 | *ppos += cnt; |
bc0c38d1 SR |
2744 | |
2745 | return cnt; | |
2746 | } | |
2747 | ||
2748 | static ssize_t | |
2749 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2750 | size_t cnt, loff_t *ppos) | |
2751 | { | |
ee6c2c1b | 2752 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
2753 | int r; |
2754 | ||
2755 | mutex_lock(&trace_types_lock); | |
2756 | if (current_trace) | |
2757 | r = sprintf(buf, "%s\n", current_trace->name); | |
2758 | else | |
2759 | r = sprintf(buf, "\n"); | |
2760 | mutex_unlock(&trace_types_lock); | |
2761 | ||
4bf39a94 | 2762 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2763 | } |
2764 | ||
b6f11df2 ACM |
2765 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2766 | { | |
2767 | tracing_reset_online_cpus(tr); | |
2768 | return t->init(tr); | |
2769 | } | |
2770 | ||
73c5162a SR |
2771 | static int tracing_resize_ring_buffer(unsigned long size) |
2772 | { | |
2773 | int ret; | |
2774 | ||
2775 | /* | |
2776 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2777 | * we use the size that was given, and we can forget about |
2778 | * expanding it later. | |
73c5162a SR |
2779 | */ |
2780 | ring_buffer_expanded = 1; | |
2781 | ||
2782 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2783 | if (ret < 0) | |
2784 | return ret; | |
2785 | ||
ef710e10 KM |
2786 | if (!current_trace->use_max_tr) |
2787 | goto out; | |
2788 | ||
73c5162a SR |
2789 | ret = ring_buffer_resize(max_tr.buffer, size); |
2790 | if (ret < 0) { | |
2791 | int r; | |
2792 | ||
2793 | r = ring_buffer_resize(global_trace.buffer, | |
2794 | global_trace.entries); | |
2795 | if (r < 0) { | |
a123c52b SR |
2796 | /* |
2797 | * AARGH! We are left with different | |
2798 | * size max buffer!!!! | |
2799 | * The max buffer is our "snapshot" buffer. | |
2800 | * When a tracer needs a snapshot (one of the | |
2801 | * latency tracers), it swaps the max buffer | |
2802 | * with the saved snap shot. We succeeded to | |
2803 | * update the size of the main buffer, but failed to | |
2804 | * update the size of the max buffer. But when we tried | |
2805 | * to reset the main buffer to the original size, we | |
2806 | * failed there too. This is very unlikely to | |
2807 | * happen, but if it does, warn and kill all | |
2808 | * tracing. | |
2809 | */ | |
73c5162a SR |
2810 | WARN_ON(1); |
2811 | tracing_disabled = 1; | |
2812 | } | |
2813 | return ret; | |
2814 | } | |
2815 | ||
ef710e10 KM |
2816 | max_tr.entries = size; |
2817 | out: | |
73c5162a SR |
2818 | global_trace.entries = size; |
2819 | ||
2820 | return ret; | |
2821 | } | |
2822 | ||
ef710e10 | 2823 | |
1852fcce SR |
2824 | /** |
2825 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2826 | * | |
2827 | * To save on memory when the tracing is never used on a system with it | |
2828 | * configured in. The ring buffers are set to a minimum size. But once | |
2829 | * a user starts to use the tracing facility, then they need to grow | |
2830 | * to their default size. | |
2831 | * | |
2832 | * This function is to be called when a tracer is about to be used. | |
2833 | */ | |
2834 | int tracing_update_buffers(void) | |
2835 | { | |
2836 | int ret = 0; | |
2837 | ||
1027fcb2 | 2838 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2839 | if (!ring_buffer_expanded) |
2840 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2841 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2842 | |
2843 | return ret; | |
2844 | } | |
2845 | ||
577b785f SR |
2846 | struct trace_option_dentry; |
2847 | ||
2848 | static struct trace_option_dentry * | |
2849 | create_trace_option_files(struct tracer *tracer); | |
2850 | ||
2851 | static void | |
2852 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2853 | ||
b2821ae6 | 2854 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2855 | { |
577b785f | 2856 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2857 | struct trace_array *tr = &global_trace; |
2858 | struct tracer *t; | |
d9e54076 | 2859 | int ret = 0; |
bc0c38d1 | 2860 | |
1027fcb2 SR |
2861 | mutex_lock(&trace_types_lock); |
2862 | ||
73c5162a SR |
2863 | if (!ring_buffer_expanded) { |
2864 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2865 | if (ret < 0) | |
59f586db | 2866 | goto out; |
73c5162a SR |
2867 | ret = 0; |
2868 | } | |
2869 | ||
bc0c38d1 SR |
2870 | for (t = trace_types; t; t = t->next) { |
2871 | if (strcmp(t->name, buf) == 0) | |
2872 | break; | |
2873 | } | |
c2931e05 FW |
2874 | if (!t) { |
2875 | ret = -EINVAL; | |
2876 | goto out; | |
2877 | } | |
2878 | if (t == current_trace) | |
bc0c38d1 SR |
2879 | goto out; |
2880 | ||
9f029e83 | 2881 | trace_branch_disable(); |
bc0c38d1 SR |
2882 | if (current_trace && current_trace->reset) |
2883 | current_trace->reset(tr); | |
ef710e10 KM |
2884 | if (current_trace && current_trace->use_max_tr) { |
2885 | /* | |
2886 | * We don't free the ring buffer. instead, resize it because | |
2887 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
2888 | * we want preserve it. | |
2889 | */ | |
2890 | ring_buffer_resize(max_tr.buffer, 1); | |
2891 | max_tr.entries = 1; | |
2892 | } | |
577b785f SR |
2893 | destroy_trace_option_files(topts); |
2894 | ||
bc0c38d1 | 2895 | current_trace = t; |
577b785f SR |
2896 | |
2897 | topts = create_trace_option_files(current_trace); | |
ef710e10 KM |
2898 | if (current_trace->use_max_tr) { |
2899 | ret = ring_buffer_resize(max_tr.buffer, global_trace.entries); | |
2900 | if (ret < 0) | |
2901 | goto out; | |
2902 | max_tr.entries = global_trace.entries; | |
2903 | } | |
577b785f | 2904 | |
1c80025a | 2905 | if (t->init) { |
b6f11df2 | 2906 | ret = tracer_init(t, tr); |
1c80025a FW |
2907 | if (ret) |
2908 | goto out; | |
2909 | } | |
bc0c38d1 | 2910 | |
9f029e83 | 2911 | trace_branch_enable(tr); |
bc0c38d1 SR |
2912 | out: |
2913 | mutex_unlock(&trace_types_lock); | |
2914 | ||
d9e54076 PZ |
2915 | return ret; |
2916 | } | |
2917 | ||
2918 | static ssize_t | |
2919 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2920 | size_t cnt, loff_t *ppos) | |
2921 | { | |
ee6c2c1b | 2922 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
2923 | int i; |
2924 | size_t ret; | |
e6e7a65a FW |
2925 | int err; |
2926 | ||
2927 | ret = cnt; | |
d9e54076 | 2928 | |
ee6c2c1b LZ |
2929 | if (cnt > MAX_TRACER_SIZE) |
2930 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
2931 | |
2932 | if (copy_from_user(&buf, ubuf, cnt)) | |
2933 | return -EFAULT; | |
2934 | ||
2935 | buf[cnt] = 0; | |
2936 | ||
2937 | /* strip ending whitespace. */ | |
2938 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2939 | buf[i] = 0; | |
2940 | ||
e6e7a65a FW |
2941 | err = tracing_set_tracer(buf); |
2942 | if (err) | |
2943 | return err; | |
d9e54076 | 2944 | |
cf8517cf | 2945 | *ppos += ret; |
bc0c38d1 | 2946 | |
c2931e05 | 2947 | return ret; |
bc0c38d1 SR |
2948 | } |
2949 | ||
2950 | static ssize_t | |
2951 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2952 | size_t cnt, loff_t *ppos) | |
2953 | { | |
2954 | unsigned long *ptr = filp->private_data; | |
2955 | char buf[64]; | |
2956 | int r; | |
2957 | ||
cffae437 | 2958 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2959 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2960 | if (r > sizeof(buf)) |
2961 | r = sizeof(buf); | |
4bf39a94 | 2962 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2963 | } |
2964 | ||
2965 | static ssize_t | |
2966 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2967 | size_t cnt, loff_t *ppos) | |
2968 | { | |
5e39841c | 2969 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2970 | char buf[64]; |
5e39841c | 2971 | unsigned long val; |
c6caeeb1 | 2972 | int ret; |
bc0c38d1 | 2973 | |
cffae437 SR |
2974 | if (cnt >= sizeof(buf)) |
2975 | return -EINVAL; | |
bc0c38d1 SR |
2976 | |
2977 | if (copy_from_user(&buf, ubuf, cnt)) | |
2978 | return -EFAULT; | |
2979 | ||
2980 | buf[cnt] = 0; | |
2981 | ||
c6caeeb1 SR |
2982 | ret = strict_strtoul(buf, 10, &val); |
2983 | if (ret < 0) | |
2984 | return ret; | |
bc0c38d1 SR |
2985 | |
2986 | *ptr = val * 1000; | |
2987 | ||
2988 | return cnt; | |
2989 | } | |
2990 | ||
b3806b43 SR |
2991 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2992 | { | |
b04cc6b1 | 2993 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2994 | struct trace_iterator *iter; |
b04cc6b1 | 2995 | int ret = 0; |
b3806b43 SR |
2996 | |
2997 | if (tracing_disabled) | |
2998 | return -ENODEV; | |
2999 | ||
b04cc6b1 FW |
3000 | mutex_lock(&trace_types_lock); |
3001 | ||
b3806b43 SR |
3002 | /* create a buffer to store the information to pass to userspace */ |
3003 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
3004 | if (!iter) { |
3005 | ret = -ENOMEM; | |
3006 | goto out; | |
3007 | } | |
b3806b43 | 3008 | |
d7350c3f FW |
3009 | /* |
3010 | * We make a copy of the current tracer to avoid concurrent | |
3011 | * changes on it while we are reading. | |
3012 | */ | |
3013 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
3014 | if (!iter->trace) { | |
3015 | ret = -ENOMEM; | |
3016 | goto fail; | |
3017 | } | |
3018 | if (current_trace) | |
3019 | *iter->trace = *current_trace; | |
3020 | ||
4462344e | 3021 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 3022 | ret = -ENOMEM; |
d7350c3f | 3023 | goto fail; |
4462344e RR |
3024 | } |
3025 | ||
a309720c | 3026 | /* trace pipe does not show start of buffer */ |
4462344e | 3027 | cpumask_setall(iter->started); |
a309720c | 3028 | |
112f38a7 SR |
3029 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
3030 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3031 | ||
b04cc6b1 | 3032 | iter->cpu_file = cpu_file; |
b3806b43 | 3033 | iter->tr = &global_trace; |
d7350c3f | 3034 | mutex_init(&iter->mutex); |
b3806b43 SR |
3035 | filp->private_data = iter; |
3036 | ||
107bad8b SR |
3037 | if (iter->trace->pipe_open) |
3038 | iter->trace->pipe_open(iter); | |
107bad8b | 3039 | |
b444786f | 3040 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
3041 | out: |
3042 | mutex_unlock(&trace_types_lock); | |
3043 | return ret; | |
d7350c3f FW |
3044 | |
3045 | fail: | |
3046 | kfree(iter->trace); | |
3047 | kfree(iter); | |
3048 | mutex_unlock(&trace_types_lock); | |
3049 | return ret; | |
b3806b43 SR |
3050 | } |
3051 | ||
3052 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
3053 | { | |
3054 | struct trace_iterator *iter = file->private_data; | |
3055 | ||
b04cc6b1 FW |
3056 | mutex_lock(&trace_types_lock); |
3057 | ||
29bf4a5e | 3058 | if (iter->trace->pipe_close) |
c521efd1 SR |
3059 | iter->trace->pipe_close(iter); |
3060 | ||
b04cc6b1 FW |
3061 | mutex_unlock(&trace_types_lock); |
3062 | ||
4462344e | 3063 | free_cpumask_var(iter->started); |
d7350c3f FW |
3064 | mutex_destroy(&iter->mutex); |
3065 | kfree(iter->trace); | |
b3806b43 | 3066 | kfree(iter); |
b3806b43 SR |
3067 | |
3068 | return 0; | |
3069 | } | |
3070 | ||
2a2cc8f7 SSP |
3071 | static unsigned int |
3072 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
3073 | { | |
3074 | struct trace_iterator *iter = filp->private_data; | |
3075 | ||
3076 | if (trace_flags & TRACE_ITER_BLOCK) { | |
3077 | /* | |
3078 | * Always select as readable when in blocking mode | |
3079 | */ | |
3080 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 3081 | } else { |
2a2cc8f7 SSP |
3082 | if (!trace_empty(iter)) |
3083 | return POLLIN | POLLRDNORM; | |
3084 | poll_wait(filp, &trace_wait, poll_table); | |
3085 | if (!trace_empty(iter)) | |
3086 | return POLLIN | POLLRDNORM; | |
3087 | ||
3088 | return 0; | |
3089 | } | |
3090 | } | |
3091 | ||
6eaaa5d5 FW |
3092 | |
3093 | void default_wait_pipe(struct trace_iterator *iter) | |
3094 | { | |
3095 | DEFINE_WAIT(wait); | |
3096 | ||
3097 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
3098 | ||
3099 | if (trace_empty(iter)) | |
3100 | schedule(); | |
3101 | ||
3102 | finish_wait(&trace_wait, &wait); | |
3103 | } | |
3104 | ||
3105 | /* | |
3106 | * This is a make-shift waitqueue. | |
3107 | * A tracer might use this callback on some rare cases: | |
3108 | * | |
3109 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
3110 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
3111 | * 2) the function tracers, trace all functions, we don't want | |
3112 | * the overhead of calling wake_up and friends | |
3113 | * (and tracing them too) | |
3114 | * | |
3115 | * Anyway, this is really very primitive wakeup. | |
3116 | */ | |
3117 | void poll_wait_pipe(struct trace_iterator *iter) | |
3118 | { | |
3119 | set_current_state(TASK_INTERRUPTIBLE); | |
3120 | /* sleep for 100 msecs, and try again. */ | |
3121 | schedule_timeout(HZ / 10); | |
3122 | } | |
3123 | ||
ff98781b EGM |
3124 | /* Must be called with trace_types_lock mutex held. */ |
3125 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
3126 | { |
3127 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 3128 | |
b3806b43 | 3129 | while (trace_empty(iter)) { |
2dc8f095 | 3130 | |
107bad8b | 3131 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 3132 | return -EAGAIN; |
107bad8b | 3133 | } |
2dc8f095 | 3134 | |
d7350c3f | 3135 | mutex_unlock(&iter->mutex); |
107bad8b | 3136 | |
6eaaa5d5 | 3137 | iter->trace->wait_pipe(iter); |
b3806b43 | 3138 | |
d7350c3f | 3139 | mutex_lock(&iter->mutex); |
107bad8b | 3140 | |
6eaaa5d5 | 3141 | if (signal_pending(current)) |
ff98781b | 3142 | return -EINTR; |
b3806b43 SR |
3143 | |
3144 | /* | |
3145 | * We block until we read something and tracing is disabled. | |
3146 | * We still block if tracing is disabled, but we have never | |
3147 | * read anything. This allows a user to cat this file, and | |
3148 | * then enable tracing. But after we have read something, | |
3149 | * we give an EOF when tracing is again disabled. | |
3150 | * | |
3151 | * iter->pos will be 0 if we haven't read anything. | |
3152 | */ | |
3153 | if (!tracer_enabled && iter->pos) | |
3154 | break; | |
b3806b43 SR |
3155 | } |
3156 | ||
ff98781b EGM |
3157 | return 1; |
3158 | } | |
3159 | ||
3160 | /* | |
3161 | * Consumer reader. | |
3162 | */ | |
3163 | static ssize_t | |
3164 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
3165 | size_t cnt, loff_t *ppos) | |
3166 | { | |
3167 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 3168 | static struct tracer *old_tracer; |
ff98781b EGM |
3169 | ssize_t sret; |
3170 | ||
3171 | /* return any leftover data */ | |
3172 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
3173 | if (sret != -EBUSY) | |
3174 | return sret; | |
3175 | ||
f9520750 | 3176 | trace_seq_init(&iter->seq); |
ff98781b | 3177 | |
d7350c3f | 3178 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 3179 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3180 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3181 | old_tracer = current_trace; | |
3182 | *iter->trace = *current_trace; | |
3183 | } | |
3184 | mutex_unlock(&trace_types_lock); | |
3185 | ||
3186 | /* | |
3187 | * Avoid more than one consumer on a single file descriptor | |
3188 | * This is just a matter of traces coherency, the ring buffer itself | |
3189 | * is protected. | |
3190 | */ | |
3191 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
3192 | if (iter->trace->read) { |
3193 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
3194 | if (sret) | |
3195 | goto out; | |
3196 | } | |
3197 | ||
3198 | waitagain: | |
3199 | sret = tracing_wait_pipe(filp); | |
3200 | if (sret <= 0) | |
3201 | goto out; | |
3202 | ||
b3806b43 | 3203 | /* stop when tracing is finished */ |
ff98781b EGM |
3204 | if (trace_empty(iter)) { |
3205 | sret = 0; | |
107bad8b | 3206 | goto out; |
ff98781b | 3207 | } |
b3806b43 SR |
3208 | |
3209 | if (cnt >= PAGE_SIZE) | |
3210 | cnt = PAGE_SIZE - 1; | |
3211 | ||
53d0aa77 | 3212 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
3213 | memset(&iter->seq, 0, |
3214 | sizeof(struct trace_iterator) - | |
3215 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 3216 | iter->pos = -1; |
b3806b43 | 3217 | |
4f535968 | 3218 | trace_event_read_lock(); |
7e53bd42 | 3219 | trace_access_lock(iter->cpu_file); |
955b61e5 | 3220 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 3221 | enum print_line_t ret; |
088b1e42 SR |
3222 | int len = iter->seq.len; |
3223 | ||
f9896bf3 | 3224 | ret = print_trace_line(iter); |
2c4f035f | 3225 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
3226 | /* don't print partial lines */ |
3227 | iter->seq.len = len; | |
b3806b43 | 3228 | break; |
088b1e42 | 3229 | } |
b91facc3 FW |
3230 | if (ret != TRACE_TYPE_NO_CONSUME) |
3231 | trace_consume(iter); | |
b3806b43 SR |
3232 | |
3233 | if (iter->seq.len >= cnt) | |
3234 | break; | |
ee5e51f5 JO |
3235 | |
3236 | /* | |
3237 | * Setting the full flag means we reached the trace_seq buffer | |
3238 | * size and we should leave by partial output condition above. | |
3239 | * One of the trace_seq_* functions is not used properly. | |
3240 | */ | |
3241 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
3242 | iter->ent->type); | |
b3806b43 | 3243 | } |
7e53bd42 | 3244 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3245 | trace_event_read_unlock(); |
b3806b43 | 3246 | |
b3806b43 | 3247 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3248 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3249 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3250 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3251 | |
3252 | /* | |
25985edc | 3253 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
3254 | * entries, go back to wait for more entries. |
3255 | */ | |
6c6c2796 | 3256 | if (sret == -EBUSY) |
9ff4b974 | 3257 | goto waitagain; |
b3806b43 | 3258 | |
107bad8b | 3259 | out: |
d7350c3f | 3260 | mutex_unlock(&iter->mutex); |
107bad8b | 3261 | |
6c6c2796 | 3262 | return sret; |
b3806b43 SR |
3263 | } |
3264 | ||
3c56819b EGM |
3265 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3266 | struct pipe_buffer *buf) | |
3267 | { | |
3268 | __free_page(buf->page); | |
3269 | } | |
3270 | ||
3271 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3272 | unsigned int idx) | |
3273 | { | |
3274 | __free_page(spd->pages[idx]); | |
3275 | } | |
3276 | ||
28dfef8f | 3277 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
3278 | .can_merge = 0, |
3279 | .map = generic_pipe_buf_map, | |
3280 | .unmap = generic_pipe_buf_unmap, | |
3281 | .confirm = generic_pipe_buf_confirm, | |
3282 | .release = tracing_pipe_buf_release, | |
3283 | .steal = generic_pipe_buf_steal, | |
3284 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3285 | }; |
3286 | ||
34cd4998 | 3287 | static size_t |
fa7c7f6e | 3288 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3289 | { |
3290 | size_t count; | |
3291 | int ret; | |
3292 | ||
3293 | /* Seq buffer is page-sized, exactly what we need. */ | |
3294 | for (;;) { | |
3295 | count = iter->seq.len; | |
3296 | ret = print_trace_line(iter); | |
3297 | count = iter->seq.len - count; | |
3298 | if (rem < count) { | |
3299 | rem = 0; | |
3300 | iter->seq.len -= count; | |
3301 | break; | |
3302 | } | |
3303 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3304 | iter->seq.len -= count; | |
3305 | break; | |
3306 | } | |
3307 | ||
74e7ff8c LJ |
3308 | if (ret != TRACE_TYPE_NO_CONSUME) |
3309 | trace_consume(iter); | |
34cd4998 | 3310 | rem -= count; |
955b61e5 | 3311 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
3312 | rem = 0; |
3313 | iter->ent = NULL; | |
3314 | break; | |
3315 | } | |
3316 | } | |
3317 | ||
3318 | return rem; | |
3319 | } | |
3320 | ||
3c56819b EGM |
3321 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3322 | loff_t *ppos, | |
3323 | struct pipe_inode_info *pipe, | |
3324 | size_t len, | |
3325 | unsigned int flags) | |
3326 | { | |
35f3d14d JA |
3327 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
3328 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
3329 | struct trace_iterator *iter = filp->private_data; |
3330 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
3331 | .pages = pages_def, |
3332 | .partial = partial_def, | |
34cd4998 SR |
3333 | .nr_pages = 0, /* This gets updated below. */ |
3334 | .flags = flags, | |
3335 | .ops = &tracing_pipe_buf_ops, | |
3336 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3337 | }; |
d7350c3f | 3338 | static struct tracer *old_tracer; |
3c56819b | 3339 | ssize_t ret; |
34cd4998 | 3340 | size_t rem; |
3c56819b EGM |
3341 | unsigned int i; |
3342 | ||
35f3d14d JA |
3343 | if (splice_grow_spd(pipe, &spd)) |
3344 | return -ENOMEM; | |
3345 | ||
d7350c3f | 3346 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3347 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3348 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3349 | old_tracer = current_trace; | |
3350 | *iter->trace = *current_trace; | |
3351 | } | |
3352 | mutex_unlock(&trace_types_lock); | |
3353 | ||
3354 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3355 | |
3356 | if (iter->trace->splice_read) { | |
3357 | ret = iter->trace->splice_read(iter, filp, | |
3358 | ppos, pipe, len, flags); | |
3359 | if (ret) | |
34cd4998 | 3360 | goto out_err; |
3c56819b EGM |
3361 | } |
3362 | ||
3363 | ret = tracing_wait_pipe(filp); | |
3364 | if (ret <= 0) | |
34cd4998 | 3365 | goto out_err; |
3c56819b | 3366 | |
955b61e5 | 3367 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 3368 | ret = -EFAULT; |
34cd4998 | 3369 | goto out_err; |
3c56819b EGM |
3370 | } |
3371 | ||
4f535968 | 3372 | trace_event_read_lock(); |
7e53bd42 | 3373 | trace_access_lock(iter->cpu_file); |
4f535968 | 3374 | |
3c56819b | 3375 | /* Fill as many pages as possible. */ |
35f3d14d JA |
3376 | for (i = 0, rem = len; i < pipe->buffers && rem; i++) { |
3377 | spd.pages[i] = alloc_page(GFP_KERNEL); | |
3378 | if (!spd.pages[i]) | |
34cd4998 | 3379 | break; |
3c56819b | 3380 | |
fa7c7f6e | 3381 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3382 | |
3383 | /* Copy the data into the page, so we can start over. */ | |
3384 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 3385 | page_address(spd.pages[i]), |
3c56819b EGM |
3386 | iter->seq.len); |
3387 | if (ret < 0) { | |
35f3d14d | 3388 | __free_page(spd.pages[i]); |
3c56819b EGM |
3389 | break; |
3390 | } | |
35f3d14d JA |
3391 | spd.partial[i].offset = 0; |
3392 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 3393 | |
f9520750 | 3394 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3395 | } |
3396 | ||
7e53bd42 | 3397 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3398 | trace_event_read_unlock(); |
d7350c3f | 3399 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3400 | |
3401 | spd.nr_pages = i; | |
3402 | ||
35f3d14d JA |
3403 | ret = splice_to_pipe(pipe, &spd); |
3404 | out: | |
3405 | splice_shrink_spd(pipe, &spd); | |
3406 | return ret; | |
3c56819b | 3407 | |
34cd4998 | 3408 | out_err: |
d7350c3f | 3409 | mutex_unlock(&iter->mutex); |
35f3d14d | 3410 | goto out; |
3c56819b EGM |
3411 | } |
3412 | ||
a98a3c3f SR |
3413 | static ssize_t |
3414 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3415 | size_t cnt, loff_t *ppos) | |
3416 | { | |
3417 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3418 | char buf[96]; |
a98a3c3f SR |
3419 | int r; |
3420 | ||
db526ca3 SR |
3421 | mutex_lock(&trace_types_lock); |
3422 | if (!ring_buffer_expanded) | |
3423 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3424 | tr->entries >> 10, | |
3425 | trace_buf_size >> 10); | |
3426 | else | |
3427 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3428 | mutex_unlock(&trace_types_lock); | |
3429 | ||
a98a3c3f SR |
3430 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3431 | } | |
3432 | ||
3433 | static ssize_t | |
3434 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3435 | size_t cnt, loff_t *ppos) | |
3436 | { | |
3437 | unsigned long val; | |
3438 | char buf[64]; | |
bf5e6519 | 3439 | int ret, cpu; |
a98a3c3f | 3440 | |
cffae437 SR |
3441 | if (cnt >= sizeof(buf)) |
3442 | return -EINVAL; | |
a98a3c3f SR |
3443 | |
3444 | if (copy_from_user(&buf, ubuf, cnt)) | |
3445 | return -EFAULT; | |
3446 | ||
3447 | buf[cnt] = 0; | |
3448 | ||
c6caeeb1 SR |
3449 | ret = strict_strtoul(buf, 10, &val); |
3450 | if (ret < 0) | |
3451 | return ret; | |
a98a3c3f SR |
3452 | |
3453 | /* must have at least 1 entry */ | |
3454 | if (!val) | |
3455 | return -EINVAL; | |
3456 | ||
3457 | mutex_lock(&trace_types_lock); | |
3458 | ||
c76f0694 | 3459 | tracing_stop(); |
a98a3c3f | 3460 | |
bf5e6519 SR |
3461 | /* disable all cpu buffers */ |
3462 | for_each_tracing_cpu(cpu) { | |
3463 | if (global_trace.data[cpu]) | |
3464 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3465 | if (max_tr.data[cpu]) | |
3466 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3467 | } | |
3468 | ||
1696b2b0 SR |
3469 | /* value is in KB */ |
3470 | val <<= 10; | |
3471 | ||
3928a8a2 | 3472 | if (val != global_trace.entries) { |
73c5162a | 3473 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3474 | if (ret < 0) { |
3475 | cnt = ret; | |
3eefae99 SR |
3476 | goto out; |
3477 | } | |
a98a3c3f SR |
3478 | } |
3479 | ||
cf8517cf | 3480 | *ppos += cnt; |
a98a3c3f | 3481 | |
19384c03 SR |
3482 | /* If check pages failed, return ENOMEM */ |
3483 | if (tracing_disabled) | |
3484 | cnt = -ENOMEM; | |
a98a3c3f | 3485 | out: |
bf5e6519 SR |
3486 | for_each_tracing_cpu(cpu) { |
3487 | if (global_trace.data[cpu]) | |
3488 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3489 | if (max_tr.data[cpu]) | |
3490 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3491 | } | |
3492 | ||
c76f0694 | 3493 | tracing_start(); |
a98a3c3f SR |
3494 | mutex_unlock(&trace_types_lock); |
3495 | ||
3496 | return cnt; | |
3497 | } | |
3498 | ||
f2942487 CE |
3499 | static int mark_printk(const char *fmt, ...) |
3500 | { | |
3501 | int ret; | |
3502 | va_list args; | |
3503 | va_start(args, fmt); | |
3504 | ret = trace_vprintk(0, fmt, args); | |
3505 | va_end(args); | |
3506 | return ret; | |
3507 | } | |
3508 | ||
5bf9a1ee PP |
3509 | static ssize_t |
3510 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3511 | size_t cnt, loff_t *fpos) | |
3512 | { | |
3513 | char *buf; | |
1aa54bca | 3514 | size_t written; |
5bf9a1ee | 3515 | |
c76f0694 | 3516 | if (tracing_disabled) |
5bf9a1ee PP |
3517 | return -EINVAL; |
3518 | ||
3519 | if (cnt > TRACE_BUF_SIZE) | |
3520 | cnt = TRACE_BUF_SIZE; | |
3521 | ||
c13d2f7c | 3522 | buf = kmalloc(cnt + 2, GFP_KERNEL); |
5bf9a1ee PP |
3523 | if (buf == NULL) |
3524 | return -ENOMEM; | |
3525 | ||
3526 | if (copy_from_user(buf, ubuf, cnt)) { | |
3527 | kfree(buf); | |
3528 | return -EFAULT; | |
3529 | } | |
c13d2f7c CE |
3530 | if (buf[cnt-1] != '\n') { |
3531 | buf[cnt] = '\n'; | |
3532 | buf[cnt+1] = '\0'; | |
3533 | } else | |
3534 | buf[cnt] = '\0'; | |
5bf9a1ee | 3535 | |
1aa54bca | 3536 | written = mark_printk("%s", buf); |
5bf9a1ee | 3537 | kfree(buf); |
1aa54bca | 3538 | *fpos += written; |
5bf9a1ee | 3539 | |
1aa54bca MS |
3540 | /* don't tell userspace we wrote more - it might confuse them */ |
3541 | if (written > cnt) | |
3542 | written = cnt; | |
3543 | ||
3544 | return written; | |
5bf9a1ee PP |
3545 | } |
3546 | ||
13f16d20 | 3547 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 3548 | { |
5079f326 Z |
3549 | int i; |
3550 | ||
3551 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 3552 | seq_printf(m, |
5079f326 Z |
3553 | "%s%s%s%s", i ? " " : "", |
3554 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3555 | i == trace_clock_id ? "]" : ""); | |
13f16d20 | 3556 | seq_putc(m, '\n'); |
5079f326 | 3557 | |
13f16d20 | 3558 | return 0; |
5079f326 Z |
3559 | } |
3560 | ||
3561 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
3562 | size_t cnt, loff_t *fpos) | |
3563 | { | |
3564 | char buf[64]; | |
3565 | const char *clockstr; | |
3566 | int i; | |
3567 | ||
3568 | if (cnt >= sizeof(buf)) | |
3569 | return -EINVAL; | |
3570 | ||
3571 | if (copy_from_user(&buf, ubuf, cnt)) | |
3572 | return -EFAULT; | |
3573 | ||
3574 | buf[cnt] = 0; | |
3575 | ||
3576 | clockstr = strstrip(buf); | |
3577 | ||
3578 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
3579 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
3580 | break; | |
3581 | } | |
3582 | if (i == ARRAY_SIZE(trace_clocks)) | |
3583 | return -EINVAL; | |
3584 | ||
3585 | trace_clock_id = i; | |
3586 | ||
3587 | mutex_lock(&trace_types_lock); | |
3588 | ||
3589 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
3590 | if (max_tr.buffer) | |
3591 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
3592 | ||
3593 | mutex_unlock(&trace_types_lock); | |
3594 | ||
3595 | *fpos += cnt; | |
3596 | ||
3597 | return cnt; | |
3598 | } | |
3599 | ||
13f16d20 LZ |
3600 | static int tracing_clock_open(struct inode *inode, struct file *file) |
3601 | { | |
3602 | if (tracing_disabled) | |
3603 | return -ENODEV; | |
3604 | return single_open(file, tracing_clock_show, NULL); | |
3605 | } | |
3606 | ||
5e2336a0 | 3607 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3608 | .open = tracing_open_generic, |
3609 | .read = tracing_max_lat_read, | |
3610 | .write = tracing_max_lat_write, | |
b444786f | 3611 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3612 | }; |
3613 | ||
5e2336a0 | 3614 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3615 | .open = tracing_open_generic, |
3616 | .read = tracing_ctrl_read, | |
3617 | .write = tracing_ctrl_write, | |
b444786f | 3618 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3619 | }; |
3620 | ||
5e2336a0 | 3621 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3622 | .open = tracing_open_generic, |
3623 | .read = tracing_set_trace_read, | |
3624 | .write = tracing_set_trace_write, | |
b444786f | 3625 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3626 | }; |
3627 | ||
5e2336a0 | 3628 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3629 | .open = tracing_open_pipe, |
2a2cc8f7 | 3630 | .poll = tracing_poll_pipe, |
4bf39a94 | 3631 | .read = tracing_read_pipe, |
3c56819b | 3632 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3633 | .release = tracing_release_pipe, |
b444786f | 3634 | .llseek = no_llseek, |
b3806b43 SR |
3635 | }; |
3636 | ||
5e2336a0 | 3637 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3638 | .open = tracing_open_generic, |
3639 | .read = tracing_entries_read, | |
3640 | .write = tracing_entries_write, | |
b444786f | 3641 | .llseek = generic_file_llseek, |
a98a3c3f SR |
3642 | }; |
3643 | ||
5e2336a0 | 3644 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3645 | .open = tracing_open_generic, |
5bf9a1ee | 3646 | .write = tracing_mark_write, |
b444786f | 3647 | .llseek = generic_file_llseek, |
5bf9a1ee PP |
3648 | }; |
3649 | ||
5079f326 | 3650 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
3651 | .open = tracing_clock_open, |
3652 | .read = seq_read, | |
3653 | .llseek = seq_lseek, | |
3654 | .release = single_release, | |
5079f326 Z |
3655 | .write = tracing_clock_write, |
3656 | }; | |
3657 | ||
2cadf913 SR |
3658 | struct ftrace_buffer_info { |
3659 | struct trace_array *tr; | |
3660 | void *spare; | |
3661 | int cpu; | |
3662 | unsigned int read; | |
3663 | }; | |
3664 | ||
3665 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3666 | { | |
3667 | int cpu = (int)(long)inode->i_private; | |
3668 | struct ftrace_buffer_info *info; | |
3669 | ||
3670 | if (tracing_disabled) | |
3671 | return -ENODEV; | |
3672 | ||
3673 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3674 | if (!info) | |
3675 | return -ENOMEM; | |
3676 | ||
3677 | info->tr = &global_trace; | |
3678 | info->cpu = cpu; | |
ddd538f3 | 3679 | info->spare = NULL; |
2cadf913 SR |
3680 | /* Force reading ring buffer for first read */ |
3681 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3682 | |
3683 | filp->private_data = info; | |
3684 | ||
d1e7e02f | 3685 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3686 | } |
3687 | ||
3688 | static ssize_t | |
3689 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3690 | size_t count, loff_t *ppos) | |
3691 | { | |
3692 | struct ftrace_buffer_info *info = filp->private_data; | |
2cadf913 SR |
3693 | ssize_t ret; |
3694 | size_t size; | |
3695 | ||
2dc5d12b SR |
3696 | if (!count) |
3697 | return 0; | |
3698 | ||
ddd538f3 LJ |
3699 | if (!info->spare) |
3700 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3701 | if (!info->spare) | |
3702 | return -ENOMEM; | |
3703 | ||
2cadf913 SR |
3704 | /* Do we have previous read data to read? */ |
3705 | if (info->read < PAGE_SIZE) | |
3706 | goto read; | |
3707 | ||
3708 | info->read = 0; | |
3709 | ||
7e53bd42 | 3710 | trace_access_lock(info->cpu); |
2cadf913 SR |
3711 | ret = ring_buffer_read_page(info->tr->buffer, |
3712 | &info->spare, | |
3713 | count, | |
3714 | info->cpu, 0); | |
7e53bd42 | 3715 | trace_access_unlock(info->cpu); |
2cadf913 SR |
3716 | if (ret < 0) |
3717 | return 0; | |
3718 | ||
2cadf913 SR |
3719 | read: |
3720 | size = PAGE_SIZE - info->read; | |
3721 | if (size > count) | |
3722 | size = count; | |
3723 | ||
3724 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3725 | if (ret == size) |
2cadf913 | 3726 | return -EFAULT; |
2dc5d12b SR |
3727 | size -= ret; |
3728 | ||
2cadf913 SR |
3729 | *ppos += size; |
3730 | info->read += size; | |
3731 | ||
3732 | return size; | |
3733 | } | |
3734 | ||
3735 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3736 | { | |
3737 | struct ftrace_buffer_info *info = file->private_data; | |
3738 | ||
ddd538f3 LJ |
3739 | if (info->spare) |
3740 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3741 | kfree(info); |
3742 | ||
3743 | return 0; | |
3744 | } | |
3745 | ||
3746 | struct buffer_ref { | |
3747 | struct ring_buffer *buffer; | |
3748 | void *page; | |
3749 | int ref; | |
3750 | }; | |
3751 | ||
3752 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3753 | struct pipe_buffer *buf) | |
3754 | { | |
3755 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3756 | ||
3757 | if (--ref->ref) | |
3758 | return; | |
3759 | ||
3760 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3761 | kfree(ref); | |
3762 | buf->private = 0; | |
3763 | } | |
3764 | ||
3765 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3766 | struct pipe_buffer *buf) | |
3767 | { | |
3768 | return 1; | |
3769 | } | |
3770 | ||
3771 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3772 | struct pipe_buffer *buf) | |
3773 | { | |
3774 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3775 | ||
3776 | ref->ref++; | |
3777 | } | |
3778 | ||
3779 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 3780 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
3781 | .can_merge = 0, |
3782 | .map = generic_pipe_buf_map, | |
3783 | .unmap = generic_pipe_buf_unmap, | |
3784 | .confirm = generic_pipe_buf_confirm, | |
3785 | .release = buffer_pipe_buf_release, | |
3786 | .steal = buffer_pipe_buf_steal, | |
3787 | .get = buffer_pipe_buf_get, | |
3788 | }; | |
3789 | ||
3790 | /* | |
3791 | * Callback from splice_to_pipe(), if we need to release some pages | |
3792 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3793 | */ | |
3794 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3795 | { | |
3796 | struct buffer_ref *ref = | |
3797 | (struct buffer_ref *)spd->partial[i].private; | |
3798 | ||
3799 | if (--ref->ref) | |
3800 | return; | |
3801 | ||
3802 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3803 | kfree(ref); | |
3804 | spd->partial[i].private = 0; | |
3805 | } | |
3806 | ||
3807 | static ssize_t | |
3808 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3809 | struct pipe_inode_info *pipe, size_t len, | |
3810 | unsigned int flags) | |
3811 | { | |
3812 | struct ftrace_buffer_info *info = file->private_data; | |
35f3d14d JA |
3813 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
3814 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 3815 | struct splice_pipe_desc spd = { |
35f3d14d JA |
3816 | .pages = pages_def, |
3817 | .partial = partial_def, | |
2cadf913 SR |
3818 | .flags = flags, |
3819 | .ops = &buffer_pipe_buf_ops, | |
3820 | .spd_release = buffer_spd_release, | |
3821 | }; | |
3822 | struct buffer_ref *ref; | |
93459c6c | 3823 | int entries, size, i; |
2cadf913 SR |
3824 | size_t ret; |
3825 | ||
35f3d14d JA |
3826 | if (splice_grow_spd(pipe, &spd)) |
3827 | return -ENOMEM; | |
3828 | ||
93cfb3c9 LJ |
3829 | if (*ppos & (PAGE_SIZE - 1)) { |
3830 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
35f3d14d JA |
3831 | ret = -EINVAL; |
3832 | goto out; | |
93cfb3c9 LJ |
3833 | } |
3834 | ||
3835 | if (len & (PAGE_SIZE - 1)) { | |
3836 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
35f3d14d JA |
3837 | if (len < PAGE_SIZE) { |
3838 | ret = -EINVAL; | |
3839 | goto out; | |
3840 | } | |
93cfb3c9 LJ |
3841 | len &= PAGE_MASK; |
3842 | } | |
3843 | ||
7e53bd42 | 3844 | trace_access_lock(info->cpu); |
93459c6c SR |
3845 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
3846 | ||
35f3d14d | 3847 | for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
3848 | struct page *page; |
3849 | int r; | |
3850 | ||
3851 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3852 | if (!ref) | |
3853 | break; | |
3854 | ||
7267fa68 | 3855 | ref->ref = 1; |
2cadf913 SR |
3856 | ref->buffer = info->tr->buffer; |
3857 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3858 | if (!ref->page) { | |
3859 | kfree(ref); | |
3860 | break; | |
3861 | } | |
3862 | ||
3863 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 3864 | len, info->cpu, 1); |
2cadf913 SR |
3865 | if (r < 0) { |
3866 | ring_buffer_free_read_page(ref->buffer, | |
3867 | ref->page); | |
3868 | kfree(ref); | |
3869 | break; | |
3870 | } | |
3871 | ||
3872 | /* | |
3873 | * zero out any left over data, this is going to | |
3874 | * user land. | |
3875 | */ | |
3876 | size = ring_buffer_page_len(ref->page); | |
3877 | if (size < PAGE_SIZE) | |
3878 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3879 | ||
3880 | page = virt_to_page(ref->page); | |
3881 | ||
3882 | spd.pages[i] = page; | |
3883 | spd.partial[i].len = PAGE_SIZE; | |
3884 | spd.partial[i].offset = 0; | |
3885 | spd.partial[i].private = (unsigned long)ref; | |
3886 | spd.nr_pages++; | |
93cfb3c9 | 3887 | *ppos += PAGE_SIZE; |
93459c6c SR |
3888 | |
3889 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
3890 | } |
3891 | ||
7e53bd42 | 3892 | trace_access_unlock(info->cpu); |
2cadf913 SR |
3893 | spd.nr_pages = i; |
3894 | ||
3895 | /* did we read anything? */ | |
3896 | if (!spd.nr_pages) { | |
3897 | if (flags & SPLICE_F_NONBLOCK) | |
3898 | ret = -EAGAIN; | |
3899 | else | |
3900 | ret = 0; | |
3901 | /* TODO: block */ | |
35f3d14d | 3902 | goto out; |
2cadf913 SR |
3903 | } |
3904 | ||
3905 | ret = splice_to_pipe(pipe, &spd); | |
35f3d14d JA |
3906 | splice_shrink_spd(pipe, &spd); |
3907 | out: | |
2cadf913 SR |
3908 | return ret; |
3909 | } | |
3910 | ||
3911 | static const struct file_operations tracing_buffers_fops = { | |
3912 | .open = tracing_buffers_open, | |
3913 | .read = tracing_buffers_read, | |
3914 | .release = tracing_buffers_release, | |
3915 | .splice_read = tracing_buffers_splice_read, | |
3916 | .llseek = no_llseek, | |
3917 | }; | |
3918 | ||
c8d77183 SR |
3919 | static ssize_t |
3920 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
3921 | size_t count, loff_t *ppos) | |
3922 | { | |
3923 | unsigned long cpu = (unsigned long)filp->private_data; | |
3924 | struct trace_array *tr = &global_trace; | |
3925 | struct trace_seq *s; | |
3926 | unsigned long cnt; | |
3927 | ||
e4f2d10f | 3928 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 3929 | if (!s) |
a646365c | 3930 | return -ENOMEM; |
c8d77183 SR |
3931 | |
3932 | trace_seq_init(s); | |
3933 | ||
3934 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
3935 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
3936 | ||
3937 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
3938 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
3939 | ||
3940 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
3941 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
3942 | ||
c8d77183 SR |
3943 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
3944 | ||
3945 | kfree(s); | |
3946 | ||
3947 | return count; | |
3948 | } | |
3949 | ||
3950 | static const struct file_operations tracing_stats_fops = { | |
3951 | .open = tracing_open_generic, | |
3952 | .read = tracing_stats_read, | |
b444786f | 3953 | .llseek = generic_file_llseek, |
c8d77183 SR |
3954 | }; |
3955 | ||
bc0c38d1 SR |
3956 | #ifdef CONFIG_DYNAMIC_FTRACE |
3957 | ||
b807c3d0 SR |
3958 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3959 | { | |
3960 | return 0; | |
3961 | } | |
3962 | ||
bc0c38d1 | 3963 | static ssize_t |
b807c3d0 | 3964 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3965 | size_t cnt, loff_t *ppos) |
3966 | { | |
a26a2a27 SR |
3967 | static char ftrace_dyn_info_buffer[1024]; |
3968 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3969 | unsigned long *p = filp->private_data; |
b807c3d0 | 3970 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3971 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3972 | int r; |
3973 | ||
b807c3d0 SR |
3974 | mutex_lock(&dyn_info_mutex); |
3975 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3976 | |
a26a2a27 | 3977 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3978 | buf[r++] = '\n'; |
3979 | ||
3980 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3981 | ||
3982 | mutex_unlock(&dyn_info_mutex); | |
3983 | ||
3984 | return r; | |
bc0c38d1 SR |
3985 | } |
3986 | ||
5e2336a0 | 3987 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3988 | .open = tracing_open_generic, |
b807c3d0 | 3989 | .read = tracing_read_dyn_info, |
b444786f | 3990 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3991 | }; |
3992 | #endif | |
3993 | ||
3994 | static struct dentry *d_tracer; | |
3995 | ||
3996 | struct dentry *tracing_init_dentry(void) | |
3997 | { | |
3998 | static int once; | |
3999 | ||
4000 | if (d_tracer) | |
4001 | return d_tracer; | |
4002 | ||
3e1f60b8 FW |
4003 | if (!debugfs_initialized()) |
4004 | return NULL; | |
4005 | ||
bc0c38d1 SR |
4006 | d_tracer = debugfs_create_dir("tracing", NULL); |
4007 | ||
4008 | if (!d_tracer && !once) { | |
4009 | once = 1; | |
4010 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
4011 | return NULL; | |
4012 | } | |
4013 | ||
4014 | return d_tracer; | |
4015 | } | |
4016 | ||
b04cc6b1 FW |
4017 | static struct dentry *d_percpu; |
4018 | ||
4019 | struct dentry *tracing_dentry_percpu(void) | |
4020 | { | |
4021 | static int once; | |
4022 | struct dentry *d_tracer; | |
4023 | ||
4024 | if (d_percpu) | |
4025 | return d_percpu; | |
4026 | ||
4027 | d_tracer = tracing_init_dentry(); | |
4028 | ||
4029 | if (!d_tracer) | |
4030 | return NULL; | |
4031 | ||
4032 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
4033 | ||
4034 | if (!d_percpu && !once) { | |
4035 | once = 1; | |
4036 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
4037 | return NULL; | |
4038 | } | |
4039 | ||
4040 | return d_percpu; | |
4041 | } | |
4042 | ||
4043 | static void tracing_init_debugfs_percpu(long cpu) | |
4044 | { | |
4045 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 4046 | struct dentry *d_cpu; |
dd49a38c | 4047 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 4048 | |
dd49a38c | 4049 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
4050 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
4051 | if (!d_cpu) { | |
4052 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
4053 | return; | |
4054 | } | |
b04cc6b1 | 4055 | |
8656e7a2 | 4056 | /* per cpu trace_pipe */ |
5452af66 FW |
4057 | trace_create_file("trace_pipe", 0444, d_cpu, |
4058 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
4059 | |
4060 | /* per cpu trace */ | |
5452af66 FW |
4061 | trace_create_file("trace", 0644, d_cpu, |
4062 | (void *) cpu, &tracing_fops); | |
7f96f93f | 4063 | |
5452af66 FW |
4064 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
4065 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 4066 | |
c8d77183 SR |
4067 | trace_create_file("stats", 0444, d_cpu, |
4068 | (void *) cpu, &tracing_stats_fops); | |
b04cc6b1 FW |
4069 | } |
4070 | ||
60a11774 SR |
4071 | #ifdef CONFIG_FTRACE_SELFTEST |
4072 | /* Let selftest have access to static functions in this file */ | |
4073 | #include "trace_selftest.c" | |
4074 | #endif | |
4075 | ||
577b785f SR |
4076 | struct trace_option_dentry { |
4077 | struct tracer_opt *opt; | |
4078 | struct tracer_flags *flags; | |
4079 | struct dentry *entry; | |
4080 | }; | |
4081 | ||
4082 | static ssize_t | |
4083 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4084 | loff_t *ppos) | |
4085 | { | |
4086 | struct trace_option_dentry *topt = filp->private_data; | |
4087 | char *buf; | |
4088 | ||
4089 | if (topt->flags->val & topt->opt->bit) | |
4090 | buf = "1\n"; | |
4091 | else | |
4092 | buf = "0\n"; | |
4093 | ||
4094 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4095 | } | |
4096 | ||
4097 | static ssize_t | |
4098 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4099 | loff_t *ppos) | |
4100 | { | |
4101 | struct trace_option_dentry *topt = filp->private_data; | |
4102 | unsigned long val; | |
4103 | char buf[64]; | |
4104 | int ret; | |
4105 | ||
4106 | if (cnt >= sizeof(buf)) | |
4107 | return -EINVAL; | |
4108 | ||
4109 | if (copy_from_user(&buf, ubuf, cnt)) | |
4110 | return -EFAULT; | |
4111 | ||
4112 | buf[cnt] = 0; | |
4113 | ||
4114 | ret = strict_strtoul(buf, 10, &val); | |
4115 | if (ret < 0) | |
4116 | return ret; | |
4117 | ||
8d18eaaf LZ |
4118 | if (val != 0 && val != 1) |
4119 | return -EINVAL; | |
577b785f | 4120 | |
8d18eaaf | 4121 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 4122 | mutex_lock(&trace_types_lock); |
8d18eaaf | 4123 | ret = __set_tracer_option(current_trace, topt->flags, |
c757bea9 | 4124 | topt->opt, !val); |
577b785f SR |
4125 | mutex_unlock(&trace_types_lock); |
4126 | if (ret) | |
4127 | return ret; | |
577b785f SR |
4128 | } |
4129 | ||
4130 | *ppos += cnt; | |
4131 | ||
4132 | return cnt; | |
4133 | } | |
4134 | ||
4135 | ||
4136 | static const struct file_operations trace_options_fops = { | |
4137 | .open = tracing_open_generic, | |
4138 | .read = trace_options_read, | |
4139 | .write = trace_options_write, | |
b444786f | 4140 | .llseek = generic_file_llseek, |
577b785f SR |
4141 | }; |
4142 | ||
a8259075 SR |
4143 | static ssize_t |
4144 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4145 | loff_t *ppos) | |
4146 | { | |
4147 | long index = (long)filp->private_data; | |
4148 | char *buf; | |
4149 | ||
4150 | if (trace_flags & (1 << index)) | |
4151 | buf = "1\n"; | |
4152 | else | |
4153 | buf = "0\n"; | |
4154 | ||
4155 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4156 | } | |
4157 | ||
4158 | static ssize_t | |
4159 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4160 | loff_t *ppos) | |
4161 | { | |
4162 | long index = (long)filp->private_data; | |
4163 | char buf[64]; | |
4164 | unsigned long val; | |
4165 | int ret; | |
4166 | ||
4167 | if (cnt >= sizeof(buf)) | |
4168 | return -EINVAL; | |
4169 | ||
4170 | if (copy_from_user(&buf, ubuf, cnt)) | |
4171 | return -EFAULT; | |
4172 | ||
4173 | buf[cnt] = 0; | |
4174 | ||
4175 | ret = strict_strtoul(buf, 10, &val); | |
4176 | if (ret < 0) | |
4177 | return ret; | |
4178 | ||
f2d84b65 | 4179 | if (val != 0 && val != 1) |
a8259075 | 4180 | return -EINVAL; |
f2d84b65 | 4181 | set_tracer_flags(1 << index, val); |
a8259075 SR |
4182 | |
4183 | *ppos += cnt; | |
4184 | ||
4185 | return cnt; | |
4186 | } | |
4187 | ||
a8259075 SR |
4188 | static const struct file_operations trace_options_core_fops = { |
4189 | .open = tracing_open_generic, | |
4190 | .read = trace_options_core_read, | |
4191 | .write = trace_options_core_write, | |
b444786f | 4192 | .llseek = generic_file_llseek, |
a8259075 SR |
4193 | }; |
4194 | ||
5452af66 FW |
4195 | struct dentry *trace_create_file(const char *name, |
4196 | mode_t mode, | |
4197 | struct dentry *parent, | |
4198 | void *data, | |
4199 | const struct file_operations *fops) | |
4200 | { | |
4201 | struct dentry *ret; | |
4202 | ||
4203 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
4204 | if (!ret) | |
4205 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
4206 | ||
4207 | return ret; | |
4208 | } | |
4209 | ||
4210 | ||
a8259075 SR |
4211 | static struct dentry *trace_options_init_dentry(void) |
4212 | { | |
4213 | struct dentry *d_tracer; | |
4214 | static struct dentry *t_options; | |
4215 | ||
4216 | if (t_options) | |
4217 | return t_options; | |
4218 | ||
4219 | d_tracer = tracing_init_dentry(); | |
4220 | if (!d_tracer) | |
4221 | return NULL; | |
4222 | ||
4223 | t_options = debugfs_create_dir("options", d_tracer); | |
4224 | if (!t_options) { | |
4225 | pr_warning("Could not create debugfs directory 'options'\n"); | |
4226 | return NULL; | |
4227 | } | |
4228 | ||
4229 | return t_options; | |
4230 | } | |
4231 | ||
577b785f SR |
4232 | static void |
4233 | create_trace_option_file(struct trace_option_dentry *topt, | |
4234 | struct tracer_flags *flags, | |
4235 | struct tracer_opt *opt) | |
4236 | { | |
4237 | struct dentry *t_options; | |
577b785f SR |
4238 | |
4239 | t_options = trace_options_init_dentry(); | |
4240 | if (!t_options) | |
4241 | return; | |
4242 | ||
4243 | topt->flags = flags; | |
4244 | topt->opt = opt; | |
4245 | ||
5452af66 | 4246 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
4247 | &trace_options_fops); |
4248 | ||
577b785f SR |
4249 | } |
4250 | ||
4251 | static struct trace_option_dentry * | |
4252 | create_trace_option_files(struct tracer *tracer) | |
4253 | { | |
4254 | struct trace_option_dentry *topts; | |
4255 | struct tracer_flags *flags; | |
4256 | struct tracer_opt *opts; | |
4257 | int cnt; | |
4258 | ||
4259 | if (!tracer) | |
4260 | return NULL; | |
4261 | ||
4262 | flags = tracer->flags; | |
4263 | ||
4264 | if (!flags || !flags->opts) | |
4265 | return NULL; | |
4266 | ||
4267 | opts = flags->opts; | |
4268 | ||
4269 | for (cnt = 0; opts[cnt].name; cnt++) | |
4270 | ; | |
4271 | ||
0cfe8245 | 4272 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
4273 | if (!topts) |
4274 | return NULL; | |
4275 | ||
4276 | for (cnt = 0; opts[cnt].name; cnt++) | |
4277 | create_trace_option_file(&topts[cnt], flags, | |
4278 | &opts[cnt]); | |
4279 | ||
4280 | return topts; | |
4281 | } | |
4282 | ||
4283 | static void | |
4284 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
4285 | { | |
4286 | int cnt; | |
4287 | ||
4288 | if (!topts) | |
4289 | return; | |
4290 | ||
4291 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
4292 | if (topts[cnt].entry) | |
4293 | debugfs_remove(topts[cnt].entry); | |
4294 | } | |
4295 | ||
4296 | kfree(topts); | |
4297 | } | |
4298 | ||
a8259075 SR |
4299 | static struct dentry * |
4300 | create_trace_option_core_file(const char *option, long index) | |
4301 | { | |
4302 | struct dentry *t_options; | |
a8259075 SR |
4303 | |
4304 | t_options = trace_options_init_dentry(); | |
4305 | if (!t_options) | |
4306 | return NULL; | |
4307 | ||
5452af66 | 4308 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 4309 | &trace_options_core_fops); |
a8259075 SR |
4310 | } |
4311 | ||
4312 | static __init void create_trace_options_dir(void) | |
4313 | { | |
4314 | struct dentry *t_options; | |
a8259075 SR |
4315 | int i; |
4316 | ||
4317 | t_options = trace_options_init_dentry(); | |
4318 | if (!t_options) | |
4319 | return; | |
4320 | ||
5452af66 FW |
4321 | for (i = 0; trace_options[i]; i++) |
4322 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4323 | } |
4324 | ||
b5ad384e | 4325 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4326 | { |
4327 | struct dentry *d_tracer; | |
b04cc6b1 | 4328 | int cpu; |
bc0c38d1 | 4329 | |
7e53bd42 LJ |
4330 | trace_access_lock_init(); |
4331 | ||
bc0c38d1 SR |
4332 | d_tracer = tracing_init_dentry(); |
4333 | ||
5452af66 FW |
4334 | trace_create_file("tracing_enabled", 0644, d_tracer, |
4335 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 4336 | |
5452af66 FW |
4337 | trace_create_file("trace_options", 0644, d_tracer, |
4338 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4339 | |
5452af66 FW |
4340 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4341 | NULL, &tracing_cpumask_fops); | |
4342 | ||
4343 | trace_create_file("trace", 0644, d_tracer, | |
4344 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 4345 | |
5452af66 FW |
4346 | trace_create_file("available_tracers", 0444, d_tracer, |
4347 | &global_trace, &show_traces_fops); | |
4348 | ||
339ae5d3 | 4349 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4350 | &global_trace, &set_tracer_fops); |
4351 | ||
5d4a9dba | 4352 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
4353 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
4354 | &tracing_max_latency, &tracing_max_lat_fops); | |
0e950173 | 4355 | #endif |
5452af66 FW |
4356 | |
4357 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4358 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 4359 | |
339ae5d3 | 4360 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4361 | NULL, &tracing_readme_fops); |
4362 | ||
4363 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4364 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4365 | |
4366 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
4367 | &global_trace, &tracing_entries_fops); | |
4368 | ||
4369 | trace_create_file("trace_marker", 0220, d_tracer, | |
4370 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4371 | |
69abe6a5 AP |
4372 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4373 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 4374 | |
5079f326 Z |
4375 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
4376 | &trace_clock_fops); | |
4377 | ||
bc0c38d1 | 4378 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4379 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4380 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4381 | #endif |
b04cc6b1 | 4382 | |
5452af66 FW |
4383 | create_trace_options_dir(); |
4384 | ||
b04cc6b1 FW |
4385 | for_each_tracing_cpu(cpu) |
4386 | tracing_init_debugfs_percpu(cpu); | |
4387 | ||
b5ad384e | 4388 | return 0; |
bc0c38d1 SR |
4389 | } |
4390 | ||
3f5a54e3 SR |
4391 | static int trace_panic_handler(struct notifier_block *this, |
4392 | unsigned long event, void *unused) | |
4393 | { | |
944ac425 | 4394 | if (ftrace_dump_on_oops) |
cecbca96 | 4395 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4396 | return NOTIFY_OK; |
4397 | } | |
4398 | ||
4399 | static struct notifier_block trace_panic_notifier = { | |
4400 | .notifier_call = trace_panic_handler, | |
4401 | .next = NULL, | |
4402 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4403 | }; | |
4404 | ||
4405 | static int trace_die_handler(struct notifier_block *self, | |
4406 | unsigned long val, | |
4407 | void *data) | |
4408 | { | |
4409 | switch (val) { | |
4410 | case DIE_OOPS: | |
944ac425 | 4411 | if (ftrace_dump_on_oops) |
cecbca96 | 4412 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4413 | break; |
4414 | default: | |
4415 | break; | |
4416 | } | |
4417 | return NOTIFY_OK; | |
4418 | } | |
4419 | ||
4420 | static struct notifier_block trace_die_notifier = { | |
4421 | .notifier_call = trace_die_handler, | |
4422 | .priority = 200 | |
4423 | }; | |
4424 | ||
4425 | /* | |
4426 | * printk is set to max of 1024, we really don't need it that big. | |
4427 | * Nothing should be printing 1000 characters anyway. | |
4428 | */ | |
4429 | #define TRACE_MAX_PRINT 1000 | |
4430 | ||
4431 | /* | |
4432 | * Define here KERN_TRACE so that we have one place to modify | |
4433 | * it if we decide to change what log level the ftrace dump | |
4434 | * should be at. | |
4435 | */ | |
428aee14 | 4436 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 4437 | |
955b61e5 | 4438 | void |
3f5a54e3 SR |
4439 | trace_printk_seq(struct trace_seq *s) |
4440 | { | |
4441 | /* Probably should print a warning here. */ | |
4442 | if (s->len >= 1000) | |
4443 | s->len = 1000; | |
4444 | ||
4445 | /* should be zero ended, but we are paranoid. */ | |
4446 | s->buffer[s->len] = 0; | |
4447 | ||
4448 | printk(KERN_TRACE "%s", s->buffer); | |
4449 | ||
f9520750 | 4450 | trace_seq_init(s); |
3f5a54e3 SR |
4451 | } |
4452 | ||
955b61e5 JW |
4453 | void trace_init_global_iter(struct trace_iterator *iter) |
4454 | { | |
4455 | iter->tr = &global_trace; | |
4456 | iter->trace = current_trace; | |
4457 | iter->cpu_file = TRACE_PIPE_ALL_CPU; | |
4458 | } | |
4459 | ||
cecbca96 FW |
4460 | static void |
4461 | __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode) | |
3f5a54e3 | 4462 | { |
445c8951 | 4463 | static arch_spinlock_t ftrace_dump_lock = |
edc35bd7 | 4464 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
3f5a54e3 SR |
4465 | /* use static because iter can be a bit big for the stack */ |
4466 | static struct trace_iterator iter; | |
cf586b61 | 4467 | unsigned int old_userobj; |
3f5a54e3 | 4468 | static int dump_ran; |
d769041f SR |
4469 | unsigned long flags; |
4470 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4471 | |
4472 | /* only one dump */ | |
cd891ae0 | 4473 | local_irq_save(flags); |
0199c4e6 | 4474 | arch_spin_lock(&ftrace_dump_lock); |
3f5a54e3 SR |
4475 | if (dump_ran) |
4476 | goto out; | |
4477 | ||
4478 | dump_ran = 1; | |
4479 | ||
0ee6b6cf | 4480 | tracing_off(); |
cf586b61 FW |
4481 | |
4482 | if (disable_tracing) | |
4483 | ftrace_kill(); | |
3f5a54e3 | 4484 | |
955b61e5 JW |
4485 | trace_init_global_iter(&iter); |
4486 | ||
d769041f | 4487 | for_each_tracing_cpu(cpu) { |
955b61e5 | 4488 | atomic_inc(&iter.tr->data[cpu]->disabled); |
d769041f SR |
4489 | } |
4490 | ||
cf586b61 FW |
4491 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4492 | ||
b54d3de9 TE |
4493 | /* don't look at user memory in panic mode */ |
4494 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4495 | ||
e543ad76 | 4496 | /* Simulate the iterator */ |
3f5a54e3 SR |
4497 | iter.tr = &global_trace; |
4498 | iter.trace = current_trace; | |
cecbca96 FW |
4499 | |
4500 | switch (oops_dump_mode) { | |
4501 | case DUMP_ALL: | |
4502 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
4503 | break; | |
4504 | case DUMP_ORIG: | |
4505 | iter.cpu_file = raw_smp_processor_id(); | |
4506 | break; | |
4507 | case DUMP_NONE: | |
4508 | goto out_enable; | |
4509 | default: | |
4510 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
4511 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
4512 | } | |
4513 | ||
4514 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 SR |
4515 | |
4516 | /* | |
4517 | * We need to stop all tracing on all CPUS to read the | |
4518 | * the next buffer. This is a bit expensive, but is | |
4519 | * not done often. We fill all what we can read, | |
4520 | * and then release the locks again. | |
4521 | */ | |
4522 | ||
3f5a54e3 SR |
4523 | while (!trace_empty(&iter)) { |
4524 | ||
4525 | if (!cnt) | |
4526 | printk(KERN_TRACE "---------------------------------\n"); | |
4527 | ||
4528 | cnt++; | |
4529 | ||
4530 | /* reset all but tr, trace, and overruns */ | |
4531 | memset(&iter.seq, 0, | |
4532 | sizeof(struct trace_iterator) - | |
4533 | offsetof(struct trace_iterator, seq)); | |
4534 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4535 | iter.pos = -1; | |
4536 | ||
955b61e5 | 4537 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
4538 | int ret; |
4539 | ||
4540 | ret = print_trace_line(&iter); | |
4541 | if (ret != TRACE_TYPE_NO_CONSUME) | |
4542 | trace_consume(&iter); | |
3f5a54e3 SR |
4543 | } |
4544 | ||
4545 | trace_printk_seq(&iter.seq); | |
4546 | } | |
4547 | ||
4548 | if (!cnt) | |
4549 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4550 | else | |
4551 | printk(KERN_TRACE "---------------------------------\n"); | |
4552 | ||
cecbca96 | 4553 | out_enable: |
cf586b61 FW |
4554 | /* Re-enable tracing if requested */ |
4555 | if (!disable_tracing) { | |
4556 | trace_flags |= old_userobj; | |
4557 | ||
4558 | for_each_tracing_cpu(cpu) { | |
955b61e5 | 4559 | atomic_dec(&iter.tr->data[cpu]->disabled); |
cf586b61 FW |
4560 | } |
4561 | tracing_on(); | |
4562 | } | |
4563 | ||
3f5a54e3 | 4564 | out: |
0199c4e6 | 4565 | arch_spin_unlock(&ftrace_dump_lock); |
cd891ae0 | 4566 | local_irq_restore(flags); |
3f5a54e3 SR |
4567 | } |
4568 | ||
cf586b61 | 4569 | /* By default: disable tracing after the dump */ |
cecbca96 | 4570 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
cf586b61 | 4571 | { |
cecbca96 | 4572 | __ftrace_dump(true, oops_dump_mode); |
cf586b61 FW |
4573 | } |
4574 | ||
3928a8a2 | 4575 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4576 | { |
73c5162a | 4577 | int ring_buf_size; |
750912fa | 4578 | enum ring_buffer_flags rb_flags; |
4c11d7ae | 4579 | int i; |
9e01c1b7 | 4580 | int ret = -ENOMEM; |
4c11d7ae | 4581 | |
750912fa | 4582 | |
9e01c1b7 RR |
4583 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4584 | goto out; | |
4585 | ||
4586 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4587 | goto out_free_buffer_mask; | |
4c11d7ae | 4588 | |
73c5162a SR |
4589 | /* To save memory, keep the ring buffer size to its minimum */ |
4590 | if (ring_buffer_expanded) | |
4591 | ring_buf_size = trace_buf_size; | |
4592 | else | |
4593 | ring_buf_size = 1; | |
4594 | ||
750912fa DS |
4595 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; |
4596 | ||
9e01c1b7 RR |
4597 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4598 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
4599 | ||
4600 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
750912fa | 4601 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, rb_flags); |
3928a8a2 SR |
4602 | if (!global_trace.buffer) { |
4603 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4604 | WARN_ON(1); | |
9e01c1b7 | 4605 | goto out_free_cpumask; |
4c11d7ae | 4606 | } |
3928a8a2 | 4607 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4608 | |
9e01c1b7 | 4609 | |
4c11d7ae | 4610 | #ifdef CONFIG_TRACER_MAX_TRACE |
750912fa | 4611 | max_tr.buffer = ring_buffer_alloc(1, rb_flags); |
3928a8a2 SR |
4612 | if (!max_tr.buffer) { |
4613 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4614 | WARN_ON(1); | |
4615 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4616 | goto out_free_cpumask; |
4c11d7ae | 4617 | } |
ef710e10 | 4618 | max_tr.entries = 1; |
a98a3c3f | 4619 | #endif |
ab46428c | 4620 | |
4c11d7ae | 4621 | /* Allocate the first page for all buffers */ |
ab46428c | 4622 | for_each_tracing_cpu(i) { |
566b0aaf | 4623 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
9705f69e | 4624 | max_tr.data[i] = &per_cpu(max_tr_data, i); |
4c11d7ae | 4625 | } |
bc0c38d1 | 4626 | |
bc0c38d1 SR |
4627 | trace_init_cmdlines(); |
4628 | ||
43a15386 | 4629 | register_tracer(&nop_trace); |
79fb0768 | 4630 | current_trace = &nop_trace; |
60a11774 SR |
4631 | /* All seems OK, enable tracing */ |
4632 | tracing_disabled = 0; | |
3928a8a2 | 4633 | |
3f5a54e3 SR |
4634 | atomic_notifier_chain_register(&panic_notifier_list, |
4635 | &trace_panic_notifier); | |
4636 | ||
4637 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4638 | |
4639 | return 0; | |
3f5a54e3 | 4640 | |
9e01c1b7 RR |
4641 | out_free_cpumask: |
4642 | free_cpumask_var(tracing_cpumask); | |
4643 | out_free_buffer_mask: | |
4644 | free_cpumask_var(tracing_buffer_mask); | |
4645 | out: | |
4646 | return ret; | |
bc0c38d1 | 4647 | } |
b2821ae6 SR |
4648 | |
4649 | __init static int clear_boot_tracer(void) | |
4650 | { | |
4651 | /* | |
4652 | * The default tracer at boot buffer is an init section. | |
4653 | * This function is called in lateinit. If we did not | |
4654 | * find the boot tracer, then clear it out, to prevent | |
4655 | * later registration from accessing the buffer that is | |
4656 | * about to be freed. | |
4657 | */ | |
4658 | if (!default_bootup_tracer) | |
4659 | return 0; | |
4660 | ||
4661 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4662 | default_bootup_tracer); | |
4663 | default_bootup_tracer = NULL; | |
4664 | ||
4665 | return 0; | |
4666 | } | |
4667 | ||
b5ad384e FW |
4668 | early_initcall(tracer_alloc_buffers); |
4669 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4670 | late_initcall(clear_boot_tracer); |