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Commit | Line | Data |
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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> |
b892e5c8 | 39 | #include <linux/nmi.h> |
bc0c38d1 | 40 | #include <linux/fs.h> |
86387f7e | 41 | |
bc0c38d1 | 42 | #include "trace.h" |
f0868d1e | 43 | #include "trace_output.h" |
bc0c38d1 | 44 | |
73c5162a SR |
45 | /* |
46 | * On boot up, the ring buffer is set to the minimum size, so that | |
47 | * we do not waste memory on systems that are not using tracing. | |
48 | */ | |
020e5f85 | 49 | int ring_buffer_expanded; |
73c5162a | 50 | |
8e1b82e0 FW |
51 | /* |
52 | * We need to change this state when a selftest is running. | |
ff32504f FW |
53 | * A selftest will lurk into the ring-buffer to count the |
54 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 55 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
56 | * at the same time, giving false positive or negative results. |
57 | */ | |
8e1b82e0 | 58 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 59 | |
b2821ae6 SR |
60 | /* |
61 | * If a tracer is running, we do not want to run SELFTEST. | |
62 | */ | |
020e5f85 | 63 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 64 | |
adf9f195 FW |
65 | /* For tracers that don't implement custom flags */ |
66 | static struct tracer_opt dummy_tracer_opt[] = { | |
67 | { } | |
68 | }; | |
69 | ||
70 | static struct tracer_flags dummy_tracer_flags = { | |
71 | .val = 0, | |
72 | .opts = dummy_tracer_opt | |
73 | }; | |
74 | ||
75 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
76 | { | |
77 | return 0; | |
78 | } | |
0f048701 SR |
79 | |
80 | /* | |
81 | * Kill all tracing for good (never come back). | |
82 | * It is initialized to 1 but will turn to zero if the initialization | |
83 | * of the tracer is successful. But that is the only place that sets | |
84 | * this back to zero. | |
85 | */ | |
4fd27358 | 86 | static int tracing_disabled = 1; |
0f048701 | 87 | |
9288f99a | 88 | DEFINE_PER_CPU(int, ftrace_cpu_disabled); |
d769041f SR |
89 | |
90 | static inline void ftrace_disable_cpu(void) | |
91 | { | |
92 | preempt_disable(); | |
dd17c8f7 | 93 | __this_cpu_inc(ftrace_cpu_disabled); |
d769041f SR |
94 | } |
95 | ||
96 | static inline void ftrace_enable_cpu(void) | |
97 | { | |
dd17c8f7 | 98 | __this_cpu_dec(ftrace_cpu_disabled); |
d769041f SR |
99 | preempt_enable(); |
100 | } | |
101 | ||
955b61e5 | 102 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 103 | |
944ac425 SR |
104 | /* |
105 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
106 | * | |
107 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
108 | * is set, then ftrace_dump is called. This will output the contents | |
109 | * of the ftrace buffers to the console. This is very useful for | |
110 | * capturing traces that lead to crashes and outputing it to a | |
111 | * serial console. | |
112 | * | |
113 | * It is default off, but you can enable it with either specifying | |
114 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
115 | * /proc/sys/kernel/ftrace_dump_on_oops |
116 | * Set 1 if you want to dump buffers of all CPUs | |
117 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 118 | */ |
cecbca96 FW |
119 | |
120 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 121 | |
b2821ae6 SR |
122 | static int tracing_set_tracer(const char *buf); |
123 | ||
ee6c2c1b LZ |
124 | #define MAX_TRACER_SIZE 100 |
125 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 126 | static char *default_bootup_tracer; |
d9e54076 | 127 | |
1beee96b | 128 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 129 | { |
ee6c2c1b | 130 | strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 131 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a SR |
132 | /* We are using ftrace early, expand it */ |
133 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
134 | return 1; |
135 | } | |
1beee96b | 136 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 137 | |
944ac425 SR |
138 | static int __init set_ftrace_dump_on_oops(char *str) |
139 | { | |
cecbca96 FW |
140 | if (*str++ != '=' || !*str) { |
141 | ftrace_dump_on_oops = DUMP_ALL; | |
142 | return 1; | |
143 | } | |
144 | ||
145 | if (!strcmp("orig_cpu", str)) { | |
146 | ftrace_dump_on_oops = DUMP_ORIG; | |
147 | return 1; | |
148 | } | |
149 | ||
150 | return 0; | |
944ac425 SR |
151 | } |
152 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 153 | |
cf8e3474 | 154 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
155 | { |
156 | nsec += 500; | |
157 | do_div(nsec, 1000); | |
158 | return nsec; | |
159 | } | |
160 | ||
4fcdae83 SR |
161 | /* |
162 | * The global_trace is the descriptor that holds the tracing | |
163 | * buffers for the live tracing. For each CPU, it contains | |
164 | * a link list of pages that will store trace entries. The | |
165 | * page descriptor of the pages in the memory is used to hold | |
166 | * the link list by linking the lru item in the page descriptor | |
167 | * to each of the pages in the buffer per CPU. | |
168 | * | |
169 | * For each active CPU there is a data field that holds the | |
170 | * pages for the buffer for that CPU. Each CPU has the same number | |
171 | * of pages allocated for its buffer. | |
172 | */ | |
bc0c38d1 SR |
173 | static struct trace_array global_trace; |
174 | ||
175 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
176 | ||
e77405ad SR |
177 | int filter_current_check_discard(struct ring_buffer *buffer, |
178 | struct ftrace_event_call *call, void *rec, | |
eb02ce01 TZ |
179 | struct ring_buffer_event *event) |
180 | { | |
e77405ad | 181 | return filter_check_discard(call, rec, buffer, event); |
eb02ce01 | 182 | } |
17c873ec | 183 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 184 | |
37886f6a SR |
185 | cycle_t ftrace_now(int cpu) |
186 | { | |
187 | u64 ts; | |
188 | ||
189 | /* Early boot up does not have a buffer yet */ | |
190 | if (!global_trace.buffer) | |
191 | return trace_clock_local(); | |
192 | ||
193 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
194 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
195 | ||
196 | return ts; | |
197 | } | |
bc0c38d1 | 198 | |
4fcdae83 SR |
199 | /* |
200 | * The max_tr is used to snapshot the global_trace when a maximum | |
201 | * latency is reached. Some tracers will use this to store a maximum | |
202 | * trace while it continues examining live traces. | |
203 | * | |
204 | * The buffers for the max_tr are set up the same as the global_trace. | |
205 | * When a snapshot is taken, the link list of the max_tr is swapped | |
206 | * with the link list of the global_trace and the buffers are reset for | |
207 | * the global_trace so the tracing can continue. | |
208 | */ | |
bc0c38d1 SR |
209 | static struct trace_array max_tr; |
210 | ||
9705f69e | 211 | static DEFINE_PER_CPU(struct trace_array_cpu, max_tr_data); |
bc0c38d1 | 212 | |
4fcdae83 | 213 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 214 | static int tracer_enabled = 1; |
4fcdae83 | 215 | |
9036990d SR |
216 | /** |
217 | * tracing_is_enabled - return tracer_enabled status | |
218 | * | |
219 | * This function is used by other tracers to know the status | |
220 | * of the tracer_enabled flag. Tracers may use this function | |
221 | * to know if it should enable their features when starting | |
222 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
223 | */ | |
224 | int tracing_is_enabled(void) | |
225 | { | |
226 | return tracer_enabled; | |
227 | } | |
228 | ||
4fcdae83 | 229 | /* |
3928a8a2 SR |
230 | * trace_buf_size is the size in bytes that is allocated |
231 | * for a buffer. Note, the number of bytes is always rounded | |
232 | * to page size. | |
3f5a54e3 SR |
233 | * |
234 | * This number is purposely set to a low number of 16384. | |
235 | * If the dump on oops happens, it will be much appreciated | |
236 | * to not have to wait for all that output. Anyway this can be | |
237 | * boot time and run time configurable. | |
4fcdae83 | 238 | */ |
3928a8a2 | 239 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 240 | |
3928a8a2 | 241 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 242 | |
4fcdae83 | 243 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 244 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
245 | |
246 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 247 | static struct tracer *current_trace __read_mostly; |
4fcdae83 | 248 | |
4fcdae83 SR |
249 | /* |
250 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 251 | */ |
bc0c38d1 | 252 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 253 | |
7e53bd42 LJ |
254 | /* |
255 | * serialize the access of the ring buffer | |
256 | * | |
257 | * ring buffer serializes readers, but it is low level protection. | |
258 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
259 | * are not protected by ring buffer. | |
260 | * | |
261 | * The content of events may become garbage if we allow other process consumes | |
262 | * these events concurrently: | |
263 | * A) the page of the consumed events may become a normal page | |
264 | * (not reader page) in ring buffer, and this page will be rewrited | |
265 | * by events producer. | |
266 | * B) The page of the consumed events may become a page for splice_read, | |
267 | * and this page will be returned to system. | |
268 | * | |
269 | * These primitives allow multi process access to different cpu ring buffer | |
270 | * concurrently. | |
271 | * | |
272 | * These primitives don't distinguish read-only and read-consume access. | |
273 | * Multi read-only access are also serialized. | |
274 | */ | |
275 | ||
276 | #ifdef CONFIG_SMP | |
277 | static DECLARE_RWSEM(all_cpu_access_lock); | |
278 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
279 | ||
280 | static inline void trace_access_lock(int cpu) | |
281 | { | |
282 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
283 | /* gain it for accessing the whole ring buffer. */ | |
284 | down_write(&all_cpu_access_lock); | |
285 | } else { | |
286 | /* gain it for accessing a cpu ring buffer. */ | |
287 | ||
288 | /* Firstly block other trace_access_lock(TRACE_PIPE_ALL_CPU). */ | |
289 | down_read(&all_cpu_access_lock); | |
290 | ||
291 | /* Secondly block other access to this @cpu ring buffer. */ | |
292 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
293 | } | |
294 | } | |
295 | ||
296 | static inline void trace_access_unlock(int cpu) | |
297 | { | |
298 | if (cpu == TRACE_PIPE_ALL_CPU) { | |
299 | up_write(&all_cpu_access_lock); | |
300 | } else { | |
301 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
302 | up_read(&all_cpu_access_lock); | |
303 | } | |
304 | } | |
305 | ||
306 | static inline void trace_access_lock_init(void) | |
307 | { | |
308 | int cpu; | |
309 | ||
310 | for_each_possible_cpu(cpu) | |
311 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
312 | } | |
313 | ||
314 | #else | |
315 | ||
316 | static DEFINE_MUTEX(access_lock); | |
317 | ||
318 | static inline void trace_access_lock(int cpu) | |
319 | { | |
320 | (void)cpu; | |
321 | mutex_lock(&access_lock); | |
322 | } | |
323 | ||
324 | static inline void trace_access_unlock(int cpu) | |
325 | { | |
326 | (void)cpu; | |
327 | mutex_unlock(&access_lock); | |
328 | } | |
329 | ||
330 | static inline void trace_access_lock_init(void) | |
331 | { | |
332 | } | |
333 | ||
334 | #endif | |
335 | ||
4fcdae83 | 336 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ |
4e655519 IM |
337 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
338 | ||
ee6bce52 | 339 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 340 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a | 341 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
77271ce4 SR |
342 | TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | |
343 | TRACE_ITER_IRQ_INFO; | |
4e655519 | 344 | |
b8de7bd1 | 345 | static int trace_stop_count; |
5389f6fa | 346 | static DEFINE_RAW_SPINLOCK(tracing_start_lock); |
b8de7bd1 | 347 | |
e7e2ee89 VN |
348 | static void wakeup_work_handler(struct work_struct *work) |
349 | { | |
350 | wake_up(&trace_wait); | |
351 | } | |
352 | ||
353 | static DECLARE_DELAYED_WORK(wakeup_work, wakeup_work_handler); | |
354 | ||
499e5470 SR |
355 | /** |
356 | * tracing_on - enable tracing buffers | |
357 | * | |
358 | * This function enables tracing buffers that may have been | |
359 | * disabled with tracing_off. | |
360 | */ | |
361 | void tracing_on(void) | |
362 | { | |
363 | if (global_trace.buffer) | |
364 | ring_buffer_record_on(global_trace.buffer); | |
365 | /* | |
366 | * This flag is only looked at when buffers haven't been | |
367 | * allocated yet. We don't really care about the race | |
368 | * between setting this flag and actually turning | |
369 | * on the buffer. | |
370 | */ | |
371 | global_trace.buffer_disabled = 0; | |
372 | } | |
373 | EXPORT_SYMBOL_GPL(tracing_on); | |
374 | ||
375 | /** | |
376 | * tracing_off - turn off tracing buffers | |
377 | * | |
378 | * This function stops the tracing buffers from recording data. | |
379 | * It does not disable any overhead the tracers themselves may | |
380 | * be causing. This function simply causes all recording to | |
381 | * the ring buffers to fail. | |
382 | */ | |
383 | void tracing_off(void) | |
384 | { | |
385 | if (global_trace.buffer) | |
386 | ring_buffer_record_on(global_trace.buffer); | |
387 | /* | |
388 | * This flag is only looked at when buffers haven't been | |
389 | * allocated yet. We don't really care about the race | |
390 | * between setting this flag and actually turning | |
391 | * on the buffer. | |
392 | */ | |
393 | global_trace.buffer_disabled = 1; | |
394 | } | |
395 | EXPORT_SYMBOL_GPL(tracing_off); | |
396 | ||
397 | /** | |
398 | * tracing_is_on - show state of ring buffers enabled | |
399 | */ | |
400 | int tracing_is_on(void) | |
401 | { | |
402 | if (global_trace.buffer) | |
403 | return ring_buffer_record_is_on(global_trace.buffer); | |
404 | return !global_trace.buffer_disabled; | |
405 | } | |
406 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
407 | ||
4fcdae83 SR |
408 | /** |
409 | * trace_wake_up - wake up tasks waiting for trace input | |
410 | * | |
e7e2ee89 VN |
411 | * Schedules a delayed work to wake up any task that is blocked on the |
412 | * trace_wait queue. These is used with trace_poll for tasks polling the | |
413 | * trace. | |
4fcdae83 | 414 | */ |
4e655519 IM |
415 | void trace_wake_up(void) |
416 | { | |
e7e2ee89 | 417 | const unsigned long delay = msecs_to_jiffies(2); |
89f19f04 AM |
418 | |
419 | if (trace_flags & TRACE_ITER_BLOCK) | |
420 | return; | |
e7e2ee89 | 421 | schedule_delayed_work(&wakeup_work, delay); |
4e655519 | 422 | } |
bc0c38d1 | 423 | |
3928a8a2 | 424 | static int __init set_buf_size(char *str) |
bc0c38d1 | 425 | { |
3928a8a2 | 426 | unsigned long buf_size; |
c6caeeb1 | 427 | |
bc0c38d1 SR |
428 | if (!str) |
429 | return 0; | |
9d612bef | 430 | buf_size = memparse(str, &str); |
c6caeeb1 | 431 | /* nr_entries can not be zero */ |
9d612bef | 432 | if (buf_size == 0) |
c6caeeb1 | 433 | return 0; |
3928a8a2 | 434 | trace_buf_size = buf_size; |
bc0c38d1 SR |
435 | return 1; |
436 | } | |
3928a8a2 | 437 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 438 | |
0e950173 TB |
439 | static int __init set_tracing_thresh(char *str) |
440 | { | |
441 | unsigned long threshhold; | |
442 | int ret; | |
443 | ||
444 | if (!str) | |
445 | return 0; | |
446 | ret = strict_strtoul(str, 0, &threshhold); | |
447 | if (ret < 0) | |
448 | return 0; | |
449 | tracing_thresh = threshhold * 1000; | |
450 | return 1; | |
451 | } | |
452 | __setup("tracing_thresh=", set_tracing_thresh); | |
453 | ||
57f50be1 SR |
454 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
455 | { | |
456 | return nsecs / 1000; | |
457 | } | |
458 | ||
4fcdae83 | 459 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
460 | static const char *trace_options[] = { |
461 | "print-parent", | |
462 | "sym-offset", | |
463 | "sym-addr", | |
464 | "verbose", | |
f9896bf3 | 465 | "raw", |
5e3ca0ec | 466 | "hex", |
cb0f12aa | 467 | "bin", |
2a2cc8f7 | 468 | "block", |
86387f7e | 469 | "stacktrace", |
5e1607a0 | 470 | "trace_printk", |
b2a866f9 | 471 | "ftrace_preempt", |
9f029e83 | 472 | "branch", |
12ef7d44 | 473 | "annotate", |
02b67518 | 474 | "userstacktrace", |
b54d3de9 | 475 | "sym-userobj", |
66896a85 | 476 | "printk-msg-only", |
c4a8e8be | 477 | "context-info", |
c032ef64 | 478 | "latency-format", |
be6f164a | 479 | "sleep-time", |
a2a16d6a | 480 | "graph-time", |
e870e9a1 | 481 | "record-cmd", |
750912fa | 482 | "overwrite", |
cf30cf67 | 483 | "disable_on_free", |
77271ce4 | 484 | "irq-info", |
bc0c38d1 SR |
485 | NULL |
486 | }; | |
487 | ||
5079f326 Z |
488 | static struct { |
489 | u64 (*func)(void); | |
490 | const char *name; | |
491 | } trace_clocks[] = { | |
492 | { trace_clock_local, "local" }, | |
493 | { trace_clock_global, "global" }, | |
6249687f | 494 | { trace_clock_counter, "counter" }, |
5079f326 Z |
495 | }; |
496 | ||
497 | int trace_clock_id; | |
498 | ||
b63f39ea | 499 | /* |
500 | * trace_parser_get_init - gets the buffer for trace parser | |
501 | */ | |
502 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
503 | { | |
504 | memset(parser, 0, sizeof(*parser)); | |
505 | ||
506 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
507 | if (!parser->buffer) | |
508 | return 1; | |
509 | ||
510 | parser->size = size; | |
511 | return 0; | |
512 | } | |
513 | ||
514 | /* | |
515 | * trace_parser_put - frees the buffer for trace parser | |
516 | */ | |
517 | void trace_parser_put(struct trace_parser *parser) | |
518 | { | |
519 | kfree(parser->buffer); | |
520 | } | |
521 | ||
522 | /* | |
523 | * trace_get_user - reads the user input string separated by space | |
524 | * (matched by isspace(ch)) | |
525 | * | |
526 | * For each string found the 'struct trace_parser' is updated, | |
527 | * and the function returns. | |
528 | * | |
529 | * Returns number of bytes read. | |
530 | * | |
531 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
532 | */ | |
533 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
534 | size_t cnt, loff_t *ppos) | |
535 | { | |
536 | char ch; | |
537 | size_t read = 0; | |
538 | ssize_t ret; | |
539 | ||
540 | if (!*ppos) | |
541 | trace_parser_clear(parser); | |
542 | ||
543 | ret = get_user(ch, ubuf++); | |
544 | if (ret) | |
545 | goto out; | |
546 | ||
547 | read++; | |
548 | cnt--; | |
549 | ||
550 | /* | |
551 | * The parser is not finished with the last write, | |
552 | * continue reading the user input without skipping spaces. | |
553 | */ | |
554 | if (!parser->cont) { | |
555 | /* skip white space */ | |
556 | while (cnt && isspace(ch)) { | |
557 | ret = get_user(ch, ubuf++); | |
558 | if (ret) | |
559 | goto out; | |
560 | read++; | |
561 | cnt--; | |
562 | } | |
563 | ||
564 | /* only spaces were written */ | |
565 | if (isspace(ch)) { | |
566 | *ppos += read; | |
567 | ret = read; | |
568 | goto out; | |
569 | } | |
570 | ||
571 | parser->idx = 0; | |
572 | } | |
573 | ||
574 | /* read the non-space input */ | |
575 | while (cnt && !isspace(ch)) { | |
3c235a33 | 576 | if (parser->idx < parser->size - 1) |
b63f39ea | 577 | parser->buffer[parser->idx++] = ch; |
578 | else { | |
579 | ret = -EINVAL; | |
580 | goto out; | |
581 | } | |
582 | ret = get_user(ch, ubuf++); | |
583 | if (ret) | |
584 | goto out; | |
585 | read++; | |
586 | cnt--; | |
587 | } | |
588 | ||
589 | /* We either got finished input or we have to wait for another call. */ | |
590 | if (isspace(ch)) { | |
591 | parser->buffer[parser->idx] = 0; | |
592 | parser->cont = false; | |
593 | } else { | |
594 | parser->cont = true; | |
595 | parser->buffer[parser->idx++] = ch; | |
596 | } | |
597 | ||
598 | *ppos += read; | |
599 | ret = read; | |
600 | ||
601 | out: | |
602 | return ret; | |
603 | } | |
604 | ||
6c6c2796 PP |
605 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
606 | { | |
607 | int len; | |
608 | int ret; | |
609 | ||
2dc5d12b SR |
610 | if (!cnt) |
611 | return 0; | |
612 | ||
6c6c2796 PP |
613 | if (s->len <= s->readpos) |
614 | return -EBUSY; | |
615 | ||
616 | len = s->len - s->readpos; | |
617 | if (cnt > len) | |
618 | cnt = len; | |
619 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 620 | if (ret == cnt) |
6c6c2796 PP |
621 | return -EFAULT; |
622 | ||
2dc5d12b SR |
623 | cnt -= ret; |
624 | ||
e74da523 | 625 | s->readpos += cnt; |
6c6c2796 | 626 | return cnt; |
214023c3 SR |
627 | } |
628 | ||
b8b94265 | 629 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
630 | { |
631 | int len; | |
3c56819b EGM |
632 | |
633 | if (s->len <= s->readpos) | |
634 | return -EBUSY; | |
635 | ||
636 | len = s->len - s->readpos; | |
637 | if (cnt > len) | |
638 | cnt = len; | |
5a26c8f0 | 639 | memcpy(buf, s->buffer + s->readpos, cnt); |
3c56819b | 640 | |
e74da523 | 641 | s->readpos += cnt; |
3c56819b EGM |
642 | return cnt; |
643 | } | |
644 | ||
5d4a9dba SR |
645 | /* |
646 | * ftrace_max_lock is used to protect the swapping of buffers | |
647 | * when taking a max snapshot. The buffers themselves are | |
648 | * protected by per_cpu spinlocks. But the action of the swap | |
649 | * needs its own lock. | |
650 | * | |
445c8951 | 651 | * This is defined as a arch_spinlock_t in order to help |
5d4a9dba SR |
652 | * with performance when lockdep debugging is enabled. |
653 | * | |
654 | * It is also used in other places outside the update_max_tr | |
655 | * so it needs to be defined outside of the | |
656 | * CONFIG_TRACER_MAX_TRACE. | |
657 | */ | |
445c8951 | 658 | static arch_spinlock_t ftrace_max_lock = |
edc35bd7 | 659 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
5d4a9dba | 660 | |
0e950173 TB |
661 | unsigned long __read_mostly tracing_thresh; |
662 | ||
5d4a9dba SR |
663 | #ifdef CONFIG_TRACER_MAX_TRACE |
664 | unsigned long __read_mostly tracing_max_latency; | |
5d4a9dba SR |
665 | |
666 | /* | |
667 | * Copy the new maximum trace into the separate maximum-trace | |
668 | * structure. (this way the maximum trace is permanently saved, | |
669 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
670 | */ | |
671 | static void | |
672 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
673 | { | |
674 | struct trace_array_cpu *data = tr->data[cpu]; | |
1acaa1b2 | 675 | struct trace_array_cpu *max_data; |
5d4a9dba SR |
676 | |
677 | max_tr.cpu = cpu; | |
678 | max_tr.time_start = data->preempt_timestamp; | |
679 | ||
8248ac05 SR |
680 | max_data = max_tr.data[cpu]; |
681 | max_data->saved_latency = tracing_max_latency; | |
682 | max_data->critical_start = data->critical_start; | |
683 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 684 | |
1acaa1b2 | 685 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 SR |
686 | max_data->pid = tsk->pid; |
687 | max_data->uid = task_uid(tsk); | |
688 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
689 | max_data->policy = tsk->policy; | |
690 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
691 | |
692 | /* record this tasks comm */ | |
693 | tracing_record_cmdline(tsk); | |
694 | } | |
695 | ||
4fcdae83 SR |
696 | /** |
697 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
698 | * @tr: tracer | |
699 | * @tsk: the task with the latency | |
700 | * @cpu: The cpu that initiated the trace. | |
701 | * | |
702 | * Flip the buffers between the @tr and the max_tr and record information | |
703 | * about which task was the cause of this latency. | |
704 | */ | |
e309b41d | 705 | void |
bc0c38d1 SR |
706 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
707 | { | |
3928a8a2 | 708 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 709 | |
b8de7bd1 SR |
710 | if (trace_stop_count) |
711 | return; | |
712 | ||
4c11d7ae | 713 | WARN_ON_ONCE(!irqs_disabled()); |
ef710e10 KM |
714 | if (!current_trace->use_max_tr) { |
715 | WARN_ON_ONCE(1); | |
716 | return; | |
717 | } | |
0199c4e6 | 718 | arch_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
719 | |
720 | tr->buffer = max_tr.buffer; | |
721 | max_tr.buffer = buf; | |
722 | ||
bc0c38d1 | 723 | __update_max_tr(tr, tsk, cpu); |
0199c4e6 | 724 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
725 | } |
726 | ||
727 | /** | |
728 | * update_max_tr_single - only copy one trace over, and reset the rest | |
729 | * @tr - tracer | |
730 | * @tsk - task with the latency | |
731 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
732 | * |
733 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 734 | */ |
e309b41d | 735 | void |
bc0c38d1 SR |
736 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
737 | { | |
3928a8a2 | 738 | int ret; |
bc0c38d1 | 739 | |
b8de7bd1 SR |
740 | if (trace_stop_count) |
741 | return; | |
742 | ||
4c11d7ae | 743 | WARN_ON_ONCE(!irqs_disabled()); |
ef710e10 KM |
744 | if (!current_trace->use_max_tr) { |
745 | WARN_ON_ONCE(1); | |
746 | return; | |
747 | } | |
748 | ||
0199c4e6 | 749 | arch_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 750 | |
d769041f SR |
751 | ftrace_disable_cpu(); |
752 | ||
3928a8a2 SR |
753 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); |
754 | ||
e8165dbb SR |
755 | if (ret == -EBUSY) { |
756 | /* | |
757 | * We failed to swap the buffer due to a commit taking | |
758 | * place on this CPU. We fail to record, but we reset | |
759 | * the max trace buffer (no one writes directly to it) | |
760 | * and flag that it failed. | |
761 | */ | |
762 | trace_array_printk(&max_tr, _THIS_IP_, | |
763 | "Failed to swap buffers due to commit in progress\n"); | |
764 | } | |
765 | ||
d769041f SR |
766 | ftrace_enable_cpu(); |
767 | ||
e8165dbb | 768 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
769 | |
770 | __update_max_tr(tr, tsk, cpu); | |
0199c4e6 | 771 | arch_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 772 | } |
5d4a9dba | 773 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 774 | |
4fcdae83 SR |
775 | /** |
776 | * register_tracer - register a tracer with the ftrace system. | |
777 | * @type - the plugin for the tracer | |
778 | * | |
779 | * Register a new plugin tracer. | |
780 | */ | |
bc0c38d1 | 781 | int register_tracer(struct tracer *type) |
e7669b8e HE |
782 | __releases(kernel_lock) |
783 | __acquires(kernel_lock) | |
bc0c38d1 SR |
784 | { |
785 | struct tracer *t; | |
bc0c38d1 SR |
786 | int ret = 0; |
787 | ||
788 | if (!type->name) { | |
789 | pr_info("Tracer must have a name\n"); | |
790 | return -1; | |
791 | } | |
792 | ||
24a461d5 | 793 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
794 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
795 | return -1; | |
796 | } | |
797 | ||
bc0c38d1 | 798 | mutex_lock(&trace_types_lock); |
86fa2f60 | 799 | |
8e1b82e0 FW |
800 | tracing_selftest_running = true; |
801 | ||
bc0c38d1 SR |
802 | for (t = trace_types; t; t = t->next) { |
803 | if (strcmp(type->name, t->name) == 0) { | |
804 | /* already found */ | |
ee6c2c1b | 805 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
806 | type->name); |
807 | ret = -1; | |
808 | goto out; | |
809 | } | |
810 | } | |
811 | ||
adf9f195 FW |
812 | if (!type->set_flag) |
813 | type->set_flag = &dummy_set_flag; | |
814 | if (!type->flags) | |
815 | type->flags = &dummy_tracer_flags; | |
816 | else | |
817 | if (!type->flags->opts) | |
818 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
819 | if (!type->wait_pipe) |
820 | type->wait_pipe = default_wait_pipe; | |
821 | ||
adf9f195 | 822 | |
60a11774 | 823 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 824 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 825 | struct tracer *saved_tracer = current_trace; |
60a11774 | 826 | struct trace_array *tr = &global_trace; |
ff32504f | 827 | |
60a11774 SR |
828 | /* |
829 | * Run a selftest on this tracer. | |
830 | * Here we reset the trace buffer, and set the current | |
831 | * tracer to be this tracer. The tracer can then run some | |
832 | * internal tracing to verify that everything is in order. | |
833 | * If we fail, we do not register this tracer. | |
834 | */ | |
76f0d073 | 835 | tracing_reset_online_cpus(tr); |
86fa2f60 | 836 | |
60a11774 | 837 | current_trace = type; |
4a0b1665 SR |
838 | |
839 | /* If we expanded the buffers, make sure the max is expanded too */ | |
840 | if (ring_buffer_expanded && type->use_max_tr) | |
438ced17 VN |
841 | ring_buffer_resize(max_tr.buffer, trace_buf_size, |
842 | RING_BUFFER_ALL_CPUS); | |
4a0b1665 | 843 | |
60a11774 SR |
844 | /* the test is responsible for initializing and enabling */ |
845 | pr_info("Testing tracer %s: ", type->name); | |
846 | ret = type->selftest(type, tr); | |
847 | /* the test is responsible for resetting too */ | |
848 | current_trace = saved_tracer; | |
60a11774 SR |
849 | if (ret) { |
850 | printk(KERN_CONT "FAILED!\n"); | |
851 | goto out; | |
852 | } | |
1d4db00a | 853 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 854 | tracing_reset_online_cpus(tr); |
86fa2f60 | 855 | |
4a0b1665 SR |
856 | /* Shrink the max buffer again */ |
857 | if (ring_buffer_expanded && type->use_max_tr) | |
438ced17 VN |
858 | ring_buffer_resize(max_tr.buffer, 1, |
859 | RING_BUFFER_ALL_CPUS); | |
4a0b1665 | 860 | |
60a11774 SR |
861 | printk(KERN_CONT "PASSED\n"); |
862 | } | |
863 | #endif | |
864 | ||
bc0c38d1 SR |
865 | type->next = trace_types; |
866 | trace_types = type; | |
60a11774 | 867 | |
bc0c38d1 | 868 | out: |
8e1b82e0 | 869 | tracing_selftest_running = false; |
bc0c38d1 SR |
870 | mutex_unlock(&trace_types_lock); |
871 | ||
dac74940 SR |
872 | if (ret || !default_bootup_tracer) |
873 | goto out_unlock; | |
874 | ||
ee6c2c1b | 875 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
876 | goto out_unlock; |
877 | ||
878 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
879 | /* Do we want this tracer to start on bootup? */ | |
880 | tracing_set_tracer(type->name); | |
881 | default_bootup_tracer = NULL; | |
882 | /* disable other selftests, since this will break it. */ | |
883 | tracing_selftest_disabled = 1; | |
b2821ae6 | 884 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
885 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
886 | type->name); | |
b2821ae6 | 887 | #endif |
b2821ae6 | 888 | |
dac74940 | 889 | out_unlock: |
bc0c38d1 SR |
890 | return ret; |
891 | } | |
892 | ||
893 | void unregister_tracer(struct tracer *type) | |
894 | { | |
895 | struct tracer **t; | |
bc0c38d1 SR |
896 | |
897 | mutex_lock(&trace_types_lock); | |
898 | for (t = &trace_types; *t; t = &(*t)->next) { | |
899 | if (*t == type) | |
900 | goto found; | |
901 | } | |
ee6c2c1b | 902 | pr_info("Tracer %s not registered\n", type->name); |
bc0c38d1 SR |
903 | goto out; |
904 | ||
905 | found: | |
906 | *t = (*t)->next; | |
b5db03c4 ACM |
907 | |
908 | if (type == current_trace && tracer_enabled) { | |
909 | tracer_enabled = 0; | |
910 | tracing_stop(); | |
911 | if (current_trace->stop) | |
912 | current_trace->stop(&global_trace); | |
913 | current_trace = &nop_trace; | |
914 | } | |
ee6c2c1b | 915 | out: |
bc0c38d1 SR |
916 | mutex_unlock(&trace_types_lock); |
917 | } | |
918 | ||
283740c6 | 919 | static void __tracing_reset(struct ring_buffer *buffer, int cpu) |
bc0c38d1 | 920 | { |
d769041f | 921 | ftrace_disable_cpu(); |
283740c6 | 922 | ring_buffer_reset_cpu(buffer, cpu); |
d769041f | 923 | ftrace_enable_cpu(); |
bc0c38d1 SR |
924 | } |
925 | ||
f633903a SR |
926 | void tracing_reset(struct trace_array *tr, int cpu) |
927 | { | |
928 | struct ring_buffer *buffer = tr->buffer; | |
929 | ||
930 | ring_buffer_record_disable(buffer); | |
931 | ||
932 | /* Make sure all commits have finished */ | |
933 | synchronize_sched(); | |
283740c6 | 934 | __tracing_reset(buffer, cpu); |
f633903a SR |
935 | |
936 | ring_buffer_record_enable(buffer); | |
937 | } | |
938 | ||
213cc060 PE |
939 | void tracing_reset_online_cpus(struct trace_array *tr) |
940 | { | |
621968cd | 941 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
942 | int cpu; |
943 | ||
621968cd SR |
944 | ring_buffer_record_disable(buffer); |
945 | ||
946 | /* Make sure all commits have finished */ | |
947 | synchronize_sched(); | |
948 | ||
213cc060 PE |
949 | tr->time_start = ftrace_now(tr->cpu); |
950 | ||
951 | for_each_online_cpu(cpu) | |
283740c6 | 952 | __tracing_reset(buffer, cpu); |
621968cd SR |
953 | |
954 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
955 | } |
956 | ||
9456f0fa SR |
957 | void tracing_reset_current(int cpu) |
958 | { | |
959 | tracing_reset(&global_trace, cpu); | |
960 | } | |
961 | ||
962 | void tracing_reset_current_online_cpus(void) | |
963 | { | |
964 | tracing_reset_online_cpus(&global_trace); | |
965 | } | |
966 | ||
bc0c38d1 | 967 | #define SAVED_CMDLINES 128 |
2c7eea4c | 968 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
969 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
970 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
971 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
972 | static int cmdline_idx; | |
edc35bd7 | 973 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
25b0b44a | 974 | |
25b0b44a | 975 | /* temporary disable recording */ |
4fd27358 | 976 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
977 | |
978 | static void trace_init_cmdlines(void) | |
979 | { | |
2c7eea4c TG |
980 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
981 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
982 | cmdline_idx = 0; |
983 | } | |
984 | ||
b5130b1e CE |
985 | int is_tracing_stopped(void) |
986 | { | |
987 | return trace_stop_count; | |
988 | } | |
989 | ||
69bb54ec SR |
990 | /** |
991 | * ftrace_off_permanent - disable all ftrace code permanently | |
992 | * | |
993 | * This should only be called when a serious anomally has | |
994 | * been detected. This will turn off the function tracing, | |
995 | * ring buffers, and other tracing utilites. It takes no | |
996 | * locks and can be called from any context. | |
997 | */ | |
998 | void ftrace_off_permanent(void) | |
999 | { | |
1000 | tracing_disabled = 1; | |
1001 | ftrace_stop(); | |
1002 | tracing_off_permanent(); | |
1003 | } | |
1004 | ||
0f048701 SR |
1005 | /** |
1006 | * tracing_start - quick start of the tracer | |
1007 | * | |
1008 | * If tracing is enabled but was stopped by tracing_stop, | |
1009 | * this will start the tracer back up. | |
1010 | */ | |
1011 | void tracing_start(void) | |
1012 | { | |
1013 | struct ring_buffer *buffer; | |
1014 | unsigned long flags; | |
1015 | ||
1016 | if (tracing_disabled) | |
1017 | return; | |
1018 | ||
5389f6fa | 1019 | raw_spin_lock_irqsave(&tracing_start_lock, flags); |
b06a8301 SR |
1020 | if (--trace_stop_count) { |
1021 | if (trace_stop_count < 0) { | |
1022 | /* Someone screwed up their debugging */ | |
1023 | WARN_ON_ONCE(1); | |
1024 | trace_stop_count = 0; | |
1025 | } | |
0f048701 SR |
1026 | goto out; |
1027 | } | |
1028 | ||
a2f80714 SR |
1029 | /* Prevent the buffers from switching */ |
1030 | arch_spin_lock(&ftrace_max_lock); | |
0f048701 SR |
1031 | |
1032 | buffer = global_trace.buffer; | |
1033 | if (buffer) | |
1034 | ring_buffer_record_enable(buffer); | |
1035 | ||
1036 | buffer = max_tr.buffer; | |
1037 | if (buffer) | |
1038 | ring_buffer_record_enable(buffer); | |
1039 | ||
a2f80714 SR |
1040 | arch_spin_unlock(&ftrace_max_lock); |
1041 | ||
0f048701 SR |
1042 | ftrace_start(); |
1043 | out: | |
5389f6fa | 1044 | raw_spin_unlock_irqrestore(&tracing_start_lock, flags); |
0f048701 SR |
1045 | } |
1046 | ||
1047 | /** | |
1048 | * tracing_stop - quick stop of the tracer | |
1049 | * | |
1050 | * Light weight way to stop tracing. Use in conjunction with | |
1051 | * tracing_start. | |
1052 | */ | |
1053 | void tracing_stop(void) | |
1054 | { | |
1055 | struct ring_buffer *buffer; | |
1056 | unsigned long flags; | |
1057 | ||
1058 | ftrace_stop(); | |
5389f6fa | 1059 | raw_spin_lock_irqsave(&tracing_start_lock, flags); |
0f048701 SR |
1060 | if (trace_stop_count++) |
1061 | goto out; | |
1062 | ||
a2f80714 SR |
1063 | /* Prevent the buffers from switching */ |
1064 | arch_spin_lock(&ftrace_max_lock); | |
1065 | ||
0f048701 SR |
1066 | buffer = global_trace.buffer; |
1067 | if (buffer) | |
1068 | ring_buffer_record_disable(buffer); | |
1069 | ||
1070 | buffer = max_tr.buffer; | |
1071 | if (buffer) | |
1072 | ring_buffer_record_disable(buffer); | |
1073 | ||
a2f80714 SR |
1074 | arch_spin_unlock(&ftrace_max_lock); |
1075 | ||
0f048701 | 1076 | out: |
5389f6fa | 1077 | raw_spin_unlock_irqrestore(&tracing_start_lock, flags); |
0f048701 SR |
1078 | } |
1079 | ||
e309b41d | 1080 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1081 | |
e309b41d | 1082 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1083 | { |
a635cf04 | 1084 | unsigned pid, idx; |
bc0c38d1 SR |
1085 | |
1086 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
1087 | return; | |
1088 | ||
1089 | /* | |
1090 | * It's not the end of the world if we don't get | |
1091 | * the lock, but we also don't want to spin | |
1092 | * nor do we want to disable interrupts, | |
1093 | * so if we miss here, then better luck next time. | |
1094 | */ | |
0199c4e6 | 1095 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
1096 | return; |
1097 | ||
1098 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 1099 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
1100 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
1101 | ||
a635cf04 CE |
1102 | /* |
1103 | * Check whether the cmdline buffer at idx has a pid | |
1104 | * mapped. We are going to overwrite that entry so we | |
1105 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1106 | * would read the new comm for the old pid. | |
1107 | */ | |
1108 | pid = map_cmdline_to_pid[idx]; | |
1109 | if (pid != NO_CMDLINE_MAP) | |
1110 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 1111 | |
a635cf04 | 1112 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
1113 | map_pid_to_cmdline[tsk->pid] = idx; |
1114 | ||
1115 | cmdline_idx = idx; | |
1116 | } | |
1117 | ||
1118 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
1119 | ||
0199c4e6 | 1120 | arch_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
1121 | } |
1122 | ||
4ca53085 | 1123 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1124 | { |
bc0c38d1 SR |
1125 | unsigned map; |
1126 | ||
4ca53085 SR |
1127 | if (!pid) { |
1128 | strcpy(comm, "<idle>"); | |
1129 | return; | |
1130 | } | |
bc0c38d1 | 1131 | |
74bf4076 SR |
1132 | if (WARN_ON_ONCE(pid < 0)) { |
1133 | strcpy(comm, "<XXX>"); | |
1134 | return; | |
1135 | } | |
1136 | ||
4ca53085 SR |
1137 | if (pid > PID_MAX_DEFAULT) { |
1138 | strcpy(comm, "<...>"); | |
1139 | return; | |
1140 | } | |
bc0c38d1 | 1141 | |
5b6045a9 | 1142 | preempt_disable(); |
0199c4e6 | 1143 | arch_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 1144 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
1145 | if (map != NO_CMDLINE_MAP) |
1146 | strcpy(comm, saved_cmdlines[map]); | |
1147 | else | |
1148 | strcpy(comm, "<...>"); | |
bc0c38d1 | 1149 | |
0199c4e6 | 1150 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1151 | preempt_enable(); |
bc0c38d1 SR |
1152 | } |
1153 | ||
e309b41d | 1154 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1155 | { |
18aecd36 TG |
1156 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
1157 | !tracing_is_on()) | |
bc0c38d1 SR |
1158 | return; |
1159 | ||
1160 | trace_save_cmdline(tsk); | |
1161 | } | |
1162 | ||
45dcd8b8 | 1163 | void |
38697053 SR |
1164 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1165 | int pc) | |
bc0c38d1 SR |
1166 | { |
1167 | struct task_struct *tsk = current; | |
bc0c38d1 | 1168 | |
777e208d SR |
1169 | entry->preempt_count = pc & 0xff; |
1170 | entry->pid = (tsk) ? tsk->pid : 0; | |
a3a4a5ac | 1171 | entry->padding = 0; |
777e208d | 1172 | entry->flags = |
9244489a | 1173 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1174 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1175 | #else |
1176 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1177 | #endif | |
bc0c38d1 SR |
1178 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1179 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
1180 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
1181 | } | |
f413cdb8 | 1182 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1183 | |
e77405ad SR |
1184 | struct ring_buffer_event * |
1185 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1186 | int type, | |
1187 | unsigned long len, | |
1188 | unsigned long flags, int pc) | |
51a763dd ACM |
1189 | { |
1190 | struct ring_buffer_event *event; | |
1191 | ||
e77405ad | 1192 | event = ring_buffer_lock_reserve(buffer, len); |
51a763dd ACM |
1193 | if (event != NULL) { |
1194 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1195 | ||
1196 | tracing_generic_entry_update(ent, flags, pc); | |
1197 | ent->type = type; | |
1198 | } | |
1199 | ||
1200 | return event; | |
1201 | } | |
51a763dd | 1202 | |
e77405ad SR |
1203 | static inline void |
1204 | __trace_buffer_unlock_commit(struct ring_buffer *buffer, | |
1205 | struct ring_buffer_event *event, | |
1206 | unsigned long flags, int pc, | |
1207 | int wake) | |
51a763dd | 1208 | { |
e77405ad | 1209 | ring_buffer_unlock_commit(buffer, event); |
51a763dd | 1210 | |
e77405ad SR |
1211 | ftrace_trace_stack(buffer, flags, 6, pc); |
1212 | ftrace_trace_userstack(buffer, flags, pc); | |
07edf712 FW |
1213 | |
1214 | if (wake) | |
1215 | trace_wake_up(); | |
1216 | } | |
1217 | ||
e77405ad SR |
1218 | void trace_buffer_unlock_commit(struct ring_buffer *buffer, |
1219 | struct ring_buffer_event *event, | |
1220 | unsigned long flags, int pc) | |
07edf712 | 1221 | { |
e77405ad | 1222 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
51a763dd ACM |
1223 | } |
1224 | ||
ef5580d0 | 1225 | struct ring_buffer_event * |
e77405ad SR |
1226 | trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, |
1227 | int type, unsigned long len, | |
ef5580d0 SR |
1228 | unsigned long flags, int pc) |
1229 | { | |
e77405ad SR |
1230 | *current_rb = global_trace.buffer; |
1231 | return trace_buffer_lock_reserve(*current_rb, | |
ef5580d0 SR |
1232 | type, len, flags, pc); |
1233 | } | |
94487d6d | 1234 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 | 1235 | |
e77405ad SR |
1236 | void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, |
1237 | struct ring_buffer_event *event, | |
ef5580d0 SR |
1238 | unsigned long flags, int pc) |
1239 | { | |
e77405ad | 1240 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 1); |
07edf712 | 1241 | } |
94487d6d | 1242 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 | 1243 | |
e77405ad SR |
1244 | void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer, |
1245 | struct ring_buffer_event *event, | |
1246 | unsigned long flags, int pc) | |
07edf712 | 1247 | { |
e77405ad | 1248 | __trace_buffer_unlock_commit(buffer, event, flags, pc, 0); |
77d9f465 | 1249 | } |
94487d6d | 1250 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 | 1251 | |
1fd8df2c MH |
1252 | void trace_nowake_buffer_unlock_commit_regs(struct ring_buffer *buffer, |
1253 | struct ring_buffer_event *event, | |
1254 | unsigned long flags, int pc, | |
1255 | struct pt_regs *regs) | |
1256 | { | |
1257 | ring_buffer_unlock_commit(buffer, event); | |
1258 | ||
1259 | ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); | |
1260 | ftrace_trace_userstack(buffer, flags, pc); | |
1261 | } | |
1262 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit_regs); | |
1263 | ||
e77405ad SR |
1264 | void trace_current_buffer_discard_commit(struct ring_buffer *buffer, |
1265 | struct ring_buffer_event *event) | |
77d9f465 | 1266 | { |
e77405ad | 1267 | ring_buffer_discard_commit(buffer, event); |
ef5580d0 | 1268 | } |
12acd473 | 1269 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 1270 | |
e309b41d | 1271 | void |
7be42151 | 1272 | trace_function(struct trace_array *tr, |
38697053 SR |
1273 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1274 | int pc) | |
bc0c38d1 | 1275 | { |
e1112b4d | 1276 | struct ftrace_event_call *call = &event_function; |
e77405ad | 1277 | struct ring_buffer *buffer = tr->buffer; |
3928a8a2 | 1278 | struct ring_buffer_event *event; |
777e208d | 1279 | struct ftrace_entry *entry; |
bc0c38d1 | 1280 | |
d769041f | 1281 | /* If we are reading the ring buffer, don't trace */ |
dd17c8f7 | 1282 | if (unlikely(__this_cpu_read(ftrace_cpu_disabled))) |
d769041f SR |
1283 | return; |
1284 | ||
e77405ad | 1285 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 1286 | flags, pc); |
3928a8a2 SR |
1287 | if (!event) |
1288 | return; | |
1289 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1290 | entry->ip = ip; |
1291 | entry->parent_ip = parent_ip; | |
e1112b4d | 1292 | |
e77405ad SR |
1293 | if (!filter_check_discard(call, entry, buffer, event)) |
1294 | ring_buffer_unlock_commit(buffer, event); | |
bc0c38d1 SR |
1295 | } |
1296 | ||
e309b41d | 1297 | void |
2e0f5761 | 1298 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1299 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1300 | int pc) | |
2e0f5761 IM |
1301 | { |
1302 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1303 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1304 | } |
1305 | ||
c0a0d0d3 | 1306 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
1307 | |
1308 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
1309 | struct ftrace_stack { | |
1310 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
1311 | }; | |
1312 | ||
1313 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
1314 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
1315 | ||
e77405ad | 1316 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 1317 | unsigned long flags, |
1fd8df2c | 1318 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 1319 | { |
e1112b4d | 1320 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1321 | struct ring_buffer_event *event; |
777e208d | 1322 | struct stack_entry *entry; |
86387f7e | 1323 | struct stack_trace trace; |
4a9bd3f1 SR |
1324 | int use_stack; |
1325 | int size = FTRACE_STACK_ENTRIES; | |
1326 | ||
1327 | trace.nr_entries = 0; | |
1328 | trace.skip = skip; | |
1329 | ||
1330 | /* | |
1331 | * Since events can happen in NMIs there's no safe way to | |
1332 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
1333 | * or NMI comes in, it will just have to use the default | |
1334 | * FTRACE_STACK_SIZE. | |
1335 | */ | |
1336 | preempt_disable_notrace(); | |
1337 | ||
1338 | use_stack = ++__get_cpu_var(ftrace_stack_reserve); | |
1339 | /* | |
1340 | * We don't need any atomic variables, just a barrier. | |
1341 | * If an interrupt comes in, we don't care, because it would | |
1342 | * have exited and put the counter back to what we want. | |
1343 | * We just need a barrier to keep gcc from moving things | |
1344 | * around. | |
1345 | */ | |
1346 | barrier(); | |
1347 | if (use_stack == 1) { | |
1348 | trace.entries = &__get_cpu_var(ftrace_stack).calls[0]; | |
1349 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; | |
1350 | ||
1351 | if (regs) | |
1352 | save_stack_trace_regs(regs, &trace); | |
1353 | else | |
1354 | save_stack_trace(&trace); | |
1355 | ||
1356 | if (trace.nr_entries > size) | |
1357 | size = trace.nr_entries; | |
1358 | } else | |
1359 | /* From now on, use_stack is a boolean */ | |
1360 | use_stack = 0; | |
1361 | ||
1362 | size *= sizeof(unsigned long); | |
86387f7e | 1363 | |
e77405ad | 1364 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 1365 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 1366 | if (!event) |
4a9bd3f1 SR |
1367 | goto out; |
1368 | entry = ring_buffer_event_data(event); | |
86387f7e | 1369 | |
4a9bd3f1 SR |
1370 | memset(&entry->caller, 0, size); |
1371 | ||
1372 | if (use_stack) | |
1373 | memcpy(&entry->caller, trace.entries, | |
1374 | trace.nr_entries * sizeof(unsigned long)); | |
1375 | else { | |
1376 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1377 | trace.entries = entry->caller; | |
1378 | if (regs) | |
1379 | save_stack_trace_regs(regs, &trace); | |
1380 | else | |
1381 | save_stack_trace(&trace); | |
1382 | } | |
1383 | ||
1384 | entry->size = trace.nr_entries; | |
86387f7e | 1385 | |
e77405ad SR |
1386 | if (!filter_check_discard(call, entry, buffer, event)) |
1387 | ring_buffer_unlock_commit(buffer, event); | |
4a9bd3f1 SR |
1388 | |
1389 | out: | |
1390 | /* Again, don't let gcc optimize things here */ | |
1391 | barrier(); | |
1392 | __get_cpu_var(ftrace_stack_reserve)--; | |
1393 | preempt_enable_notrace(); | |
1394 | ||
f0a920d5 IM |
1395 | } |
1396 | ||
1fd8df2c MH |
1397 | void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, |
1398 | int skip, int pc, struct pt_regs *regs) | |
1399 | { | |
1400 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1401 | return; | |
1402 | ||
1403 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); | |
1404 | } | |
1405 | ||
e77405ad SR |
1406 | void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, |
1407 | int skip, int pc) | |
53614991 SR |
1408 | { |
1409 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1410 | return; | |
1411 | ||
1fd8df2c | 1412 | __ftrace_trace_stack(buffer, flags, skip, pc, NULL); |
53614991 SR |
1413 | } |
1414 | ||
c0a0d0d3 FW |
1415 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1416 | int pc) | |
38697053 | 1417 | { |
1fd8df2c | 1418 | __ftrace_trace_stack(tr->buffer, flags, skip, pc, NULL); |
38697053 SR |
1419 | } |
1420 | ||
03889384 SR |
1421 | /** |
1422 | * trace_dump_stack - record a stack back trace in the trace buffer | |
1423 | */ | |
1424 | void trace_dump_stack(void) | |
1425 | { | |
1426 | unsigned long flags; | |
1427 | ||
1428 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 1429 | return; |
03889384 SR |
1430 | |
1431 | local_save_flags(flags); | |
1432 | ||
1433 | /* skipping 3 traces, seems to get us at the caller of this function */ | |
1fd8df2c | 1434 | __ftrace_trace_stack(global_trace.buffer, flags, 3, preempt_count(), NULL); |
03889384 SR |
1435 | } |
1436 | ||
91e86e56 SR |
1437 | static DEFINE_PER_CPU(int, user_stack_count); |
1438 | ||
e77405ad SR |
1439 | void |
1440 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 1441 | { |
e1112b4d | 1442 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1443 | struct ring_buffer_event *event; |
02b67518 TE |
1444 | struct userstack_entry *entry; |
1445 | struct stack_trace trace; | |
02b67518 TE |
1446 | |
1447 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1448 | return; | |
1449 | ||
b6345879 SR |
1450 | /* |
1451 | * NMIs can not handle page faults, even with fix ups. | |
1452 | * The save user stack can (and often does) fault. | |
1453 | */ | |
1454 | if (unlikely(in_nmi())) | |
1455 | return; | |
02b67518 | 1456 | |
91e86e56 SR |
1457 | /* |
1458 | * prevent recursion, since the user stack tracing may | |
1459 | * trigger other kernel events. | |
1460 | */ | |
1461 | preempt_disable(); | |
1462 | if (__this_cpu_read(user_stack_count)) | |
1463 | goto out; | |
1464 | ||
1465 | __this_cpu_inc(user_stack_count); | |
1466 | ||
e77405ad | 1467 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 1468 | sizeof(*entry), flags, pc); |
02b67518 | 1469 | if (!event) |
1dbd1951 | 1470 | goto out_drop_count; |
02b67518 | 1471 | entry = ring_buffer_event_data(event); |
02b67518 | 1472 | |
48659d31 | 1473 | entry->tgid = current->tgid; |
02b67518 TE |
1474 | memset(&entry->caller, 0, sizeof(entry->caller)); |
1475 | ||
1476 | trace.nr_entries = 0; | |
1477 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1478 | trace.skip = 0; | |
1479 | trace.entries = entry->caller; | |
1480 | ||
1481 | save_stack_trace_user(&trace); | |
e77405ad SR |
1482 | if (!filter_check_discard(call, entry, buffer, event)) |
1483 | ring_buffer_unlock_commit(buffer, event); | |
91e86e56 | 1484 | |
1dbd1951 | 1485 | out_drop_count: |
91e86e56 | 1486 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
1487 | out: |
1488 | preempt_enable(); | |
02b67518 TE |
1489 | } |
1490 | ||
4fd27358 HE |
1491 | #ifdef UNUSED |
1492 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1493 | { |
7be42151 | 1494 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1495 | } |
4fd27358 | 1496 | #endif /* UNUSED */ |
02b67518 | 1497 | |
c0a0d0d3 FW |
1498 | #endif /* CONFIG_STACKTRACE */ |
1499 | ||
07d777fe SR |
1500 | /* created for use with alloc_percpu */ |
1501 | struct trace_buffer_struct { | |
1502 | char buffer[TRACE_BUF_SIZE]; | |
1503 | }; | |
1504 | ||
1505 | static struct trace_buffer_struct *trace_percpu_buffer; | |
1506 | static struct trace_buffer_struct *trace_percpu_sirq_buffer; | |
1507 | static struct trace_buffer_struct *trace_percpu_irq_buffer; | |
1508 | static struct trace_buffer_struct *trace_percpu_nmi_buffer; | |
1509 | ||
1510 | /* | |
1511 | * The buffer used is dependent on the context. There is a per cpu | |
1512 | * buffer for normal context, softirq contex, hard irq context and | |
1513 | * for NMI context. Thise allows for lockless recording. | |
1514 | * | |
1515 | * Note, if the buffers failed to be allocated, then this returns NULL | |
1516 | */ | |
1517 | static char *get_trace_buf(void) | |
1518 | { | |
1519 | struct trace_buffer_struct *percpu_buffer; | |
1520 | struct trace_buffer_struct *buffer; | |
1521 | ||
1522 | /* | |
1523 | * If we have allocated per cpu buffers, then we do not | |
1524 | * need to do any locking. | |
1525 | */ | |
1526 | if (in_nmi()) | |
1527 | percpu_buffer = trace_percpu_nmi_buffer; | |
1528 | else if (in_irq()) | |
1529 | percpu_buffer = trace_percpu_irq_buffer; | |
1530 | else if (in_softirq()) | |
1531 | percpu_buffer = trace_percpu_sirq_buffer; | |
1532 | else | |
1533 | percpu_buffer = trace_percpu_buffer; | |
1534 | ||
1535 | if (!percpu_buffer) | |
1536 | return NULL; | |
1537 | ||
1538 | buffer = per_cpu_ptr(percpu_buffer, smp_processor_id()); | |
1539 | ||
1540 | return buffer->buffer; | |
1541 | } | |
1542 | ||
1543 | static int alloc_percpu_trace_buffer(void) | |
1544 | { | |
1545 | struct trace_buffer_struct *buffers; | |
1546 | struct trace_buffer_struct *sirq_buffers; | |
1547 | struct trace_buffer_struct *irq_buffers; | |
1548 | struct trace_buffer_struct *nmi_buffers; | |
1549 | ||
1550 | buffers = alloc_percpu(struct trace_buffer_struct); | |
1551 | if (!buffers) | |
1552 | goto err_warn; | |
1553 | ||
1554 | sirq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1555 | if (!sirq_buffers) | |
1556 | goto err_sirq; | |
1557 | ||
1558 | irq_buffers = alloc_percpu(struct trace_buffer_struct); | |
1559 | if (!irq_buffers) | |
1560 | goto err_irq; | |
1561 | ||
1562 | nmi_buffers = alloc_percpu(struct trace_buffer_struct); | |
1563 | if (!nmi_buffers) | |
1564 | goto err_nmi; | |
1565 | ||
1566 | trace_percpu_buffer = buffers; | |
1567 | trace_percpu_sirq_buffer = sirq_buffers; | |
1568 | trace_percpu_irq_buffer = irq_buffers; | |
1569 | trace_percpu_nmi_buffer = nmi_buffers; | |
1570 | ||
1571 | return 0; | |
1572 | ||
1573 | err_nmi: | |
1574 | free_percpu(irq_buffers); | |
1575 | err_irq: | |
1576 | free_percpu(sirq_buffers); | |
1577 | err_sirq: | |
1578 | free_percpu(buffers); | |
1579 | err_warn: | |
1580 | WARN(1, "Could not allocate percpu trace_printk buffer"); | |
1581 | return -ENOMEM; | |
1582 | } | |
1583 | ||
1584 | void trace_printk_init_buffers(void) | |
1585 | { | |
1586 | static int buffers_allocated; | |
1587 | ||
1588 | if (buffers_allocated) | |
1589 | return; | |
1590 | ||
1591 | if (alloc_percpu_trace_buffer()) | |
1592 | return; | |
1593 | ||
1594 | pr_info("ftrace: Allocated trace_printk buffers\n"); | |
1595 | ||
1596 | buffers_allocated = 1; | |
1597 | } | |
1598 | ||
769b0441 | 1599 | /** |
48ead020 | 1600 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1601 | * |
1602 | */ | |
40ce74f1 | 1603 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1604 | { |
e1112b4d | 1605 | struct ftrace_event_call *call = &event_bprint; |
769b0441 | 1606 | struct ring_buffer_event *event; |
e77405ad | 1607 | struct ring_buffer *buffer; |
769b0441 | 1608 | struct trace_array *tr = &global_trace; |
48ead020 | 1609 | struct bprint_entry *entry; |
769b0441 | 1610 | unsigned long flags; |
07d777fe SR |
1611 | char *tbuffer; |
1612 | int len = 0, size, pc; | |
769b0441 FW |
1613 | |
1614 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1615 | return 0; | |
1616 | ||
1617 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1618 | pause_graph_tracing(); | |
1619 | ||
1620 | pc = preempt_count(); | |
5168ae50 | 1621 | preempt_disable_notrace(); |
769b0441 | 1622 | |
07d777fe SR |
1623 | tbuffer = get_trace_buf(); |
1624 | if (!tbuffer) { | |
1625 | len = 0; | |
769b0441 | 1626 | goto out; |
07d777fe | 1627 | } |
769b0441 | 1628 | |
07d777fe | 1629 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 1630 | |
07d777fe SR |
1631 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
1632 | goto out; | |
769b0441 | 1633 | |
07d777fe | 1634 | local_save_flags(flags); |
769b0441 | 1635 | size = sizeof(*entry) + sizeof(u32) * len; |
e77405ad SR |
1636 | buffer = tr->buffer; |
1637 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, | |
1638 | flags, pc); | |
769b0441 | 1639 | if (!event) |
07d777fe | 1640 | goto out; |
769b0441 FW |
1641 | entry = ring_buffer_event_data(event); |
1642 | entry->ip = ip; | |
769b0441 FW |
1643 | entry->fmt = fmt; |
1644 | ||
07d777fe | 1645 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
d931369b | 1646 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1647 | ring_buffer_unlock_commit(buffer, event); |
d931369b SR |
1648 | ftrace_trace_stack(buffer, flags, 6, pc); |
1649 | } | |
769b0441 | 1650 | |
769b0441 | 1651 | out: |
5168ae50 | 1652 | preempt_enable_notrace(); |
769b0441 FW |
1653 | unpause_graph_tracing(); |
1654 | ||
1655 | return len; | |
1656 | } | |
48ead020 FW |
1657 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1658 | ||
659372d3 SR |
1659 | int trace_array_printk(struct trace_array *tr, |
1660 | unsigned long ip, const char *fmt, ...) | |
1661 | { | |
1662 | int ret; | |
1663 | va_list ap; | |
1664 | ||
1665 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
1666 | return 0; | |
1667 | ||
1668 | va_start(ap, fmt); | |
1669 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
1670 | va_end(ap); | |
1671 | return ret; | |
1672 | } | |
1673 | ||
1674 | int trace_array_vprintk(struct trace_array *tr, | |
1675 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 1676 | { |
e1112b4d | 1677 | struct ftrace_event_call *call = &event_print; |
48ead020 | 1678 | struct ring_buffer_event *event; |
e77405ad | 1679 | struct ring_buffer *buffer; |
07d777fe | 1680 | int len = 0, size, pc; |
48ead020 | 1681 | struct print_entry *entry; |
07d777fe SR |
1682 | unsigned long flags; |
1683 | char *tbuffer; | |
48ead020 FW |
1684 | |
1685 | if (tracing_disabled || tracing_selftest_running) | |
1686 | return 0; | |
1687 | ||
07d777fe SR |
1688 | /* Don't pollute graph traces with trace_vprintk internals */ |
1689 | pause_graph_tracing(); | |
1690 | ||
48ead020 FW |
1691 | pc = preempt_count(); |
1692 | preempt_disable_notrace(); | |
48ead020 | 1693 | |
07d777fe SR |
1694 | |
1695 | tbuffer = get_trace_buf(); | |
1696 | if (!tbuffer) { | |
1697 | len = 0; | |
48ead020 | 1698 | goto out; |
07d777fe | 1699 | } |
48ead020 | 1700 | |
07d777fe SR |
1701 | len = vsnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
1702 | if (len > TRACE_BUF_SIZE) | |
1703 | goto out; | |
48ead020 | 1704 | |
07d777fe | 1705 | local_save_flags(flags); |
48ead020 | 1706 | size = sizeof(*entry) + len + 1; |
e77405ad SR |
1707 | buffer = tr->buffer; |
1708 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
07d777fe | 1709 | flags, pc); |
48ead020 | 1710 | if (!event) |
07d777fe | 1711 | goto out; |
48ead020 | 1712 | entry = ring_buffer_event_data(event); |
c13d2f7c | 1713 | entry->ip = ip; |
48ead020 | 1714 | |
07d777fe | 1715 | memcpy(&entry->buf, tbuffer, len); |
c13d2f7c | 1716 | entry->buf[len] = '\0'; |
d931369b | 1717 | if (!filter_check_discard(call, entry, buffer, event)) { |
e77405ad | 1718 | ring_buffer_unlock_commit(buffer, event); |
07d777fe | 1719 | ftrace_trace_stack(buffer, flags, 6, pc); |
d931369b | 1720 | } |
48ead020 FW |
1721 | out: |
1722 | preempt_enable_notrace(); | |
07d777fe | 1723 | unpause_graph_tracing(); |
48ead020 FW |
1724 | |
1725 | return len; | |
1726 | } | |
659372d3 SR |
1727 | |
1728 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) | |
1729 | { | |
a813a159 | 1730 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 1731 | } |
769b0441 FW |
1732 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1733 | ||
e2ac8ef5 | 1734 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1735 | { |
d769041f SR |
1736 | /* Don't allow ftrace to trace into the ring buffers */ |
1737 | ftrace_disable_cpu(); | |
1738 | ||
5a90f577 | 1739 | iter->idx++; |
d769041f SR |
1740 | if (iter->buffer_iter[iter->cpu]) |
1741 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1742 | ||
1743 | ftrace_enable_cpu(); | |
5a90f577 SR |
1744 | } |
1745 | ||
e309b41d | 1746 | static struct trace_entry * |
bc21b478 SR |
1747 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
1748 | unsigned long *lost_events) | |
dd0e545f | 1749 | { |
3928a8a2 SR |
1750 | struct ring_buffer_event *event; |
1751 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1752 | |
d769041f SR |
1753 | /* Don't allow ftrace to trace into the ring buffers */ |
1754 | ftrace_disable_cpu(); | |
1755 | ||
1756 | if (buf_iter) | |
1757 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1758 | else | |
bc21b478 SR |
1759 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts, |
1760 | lost_events); | |
d769041f SR |
1761 | |
1762 | ftrace_enable_cpu(); | |
1763 | ||
4a9bd3f1 SR |
1764 | if (event) { |
1765 | iter->ent_size = ring_buffer_event_length(event); | |
1766 | return ring_buffer_event_data(event); | |
1767 | } | |
1768 | iter->ent_size = 0; | |
1769 | return NULL; | |
dd0e545f | 1770 | } |
d769041f | 1771 | |
dd0e545f | 1772 | static struct trace_entry * |
bc21b478 SR |
1773 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
1774 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 1775 | { |
3928a8a2 | 1776 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1777 | struct trace_entry *ent, *next = NULL; |
aa27497c | 1778 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 1779 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1780 | u64 next_ts = 0, ts; |
bc0c38d1 | 1781 | int next_cpu = -1; |
12b5da34 | 1782 | int next_size = 0; |
bc0c38d1 SR |
1783 | int cpu; |
1784 | ||
b04cc6b1 FW |
1785 | /* |
1786 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1787 | * all cpu and peek directly. | |
1788 | */ | |
1789 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1790 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1791 | return NULL; | |
bc21b478 | 1792 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
1793 | if (ent_cpu) |
1794 | *ent_cpu = cpu_file; | |
1795 | ||
1796 | return ent; | |
1797 | } | |
1798 | ||
ab46428c | 1799 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1800 | |
3928a8a2 SR |
1801 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1802 | continue; | |
dd0e545f | 1803 | |
bc21b478 | 1804 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 1805 | |
cdd31cd2 IM |
1806 | /* |
1807 | * Pick the entry with the smallest timestamp: | |
1808 | */ | |
3928a8a2 | 1809 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1810 | next = ent; |
1811 | next_cpu = cpu; | |
3928a8a2 | 1812 | next_ts = ts; |
bc21b478 | 1813 | next_lost = lost_events; |
12b5da34 | 1814 | next_size = iter->ent_size; |
bc0c38d1 SR |
1815 | } |
1816 | } | |
1817 | ||
12b5da34 SR |
1818 | iter->ent_size = next_size; |
1819 | ||
bc0c38d1 SR |
1820 | if (ent_cpu) |
1821 | *ent_cpu = next_cpu; | |
1822 | ||
3928a8a2 SR |
1823 | if (ent_ts) |
1824 | *ent_ts = next_ts; | |
1825 | ||
bc21b478 SR |
1826 | if (missing_events) |
1827 | *missing_events = next_lost; | |
1828 | ||
bc0c38d1 SR |
1829 | return next; |
1830 | } | |
1831 | ||
dd0e545f | 1832 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1833 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1834 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1835 | { |
bc21b478 | 1836 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
1837 | } |
1838 | ||
1839 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 1840 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 1841 | { |
bc21b478 SR |
1842 | iter->ent = __find_next_entry(iter, &iter->cpu, |
1843 | &iter->lost_events, &iter->ts); | |
dd0e545f | 1844 | |
3928a8a2 | 1845 | if (iter->ent) |
e2ac8ef5 | 1846 | trace_iterator_increment(iter); |
dd0e545f | 1847 | |
3928a8a2 | 1848 | return iter->ent ? iter : NULL; |
b3806b43 | 1849 | } |
bc0c38d1 | 1850 | |
e309b41d | 1851 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1852 | { |
d769041f SR |
1853 | /* Don't allow ftrace to trace into the ring buffers */ |
1854 | ftrace_disable_cpu(); | |
bc21b478 SR |
1855 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts, |
1856 | &iter->lost_events); | |
d769041f | 1857 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1858 | } |
1859 | ||
e309b41d | 1860 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1861 | { |
1862 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1863 | int i = (int)*pos; |
4e3c3333 | 1864 | void *ent; |
bc0c38d1 | 1865 | |
a63ce5b3 SR |
1866 | WARN_ON_ONCE(iter->leftover); |
1867 | ||
bc0c38d1 SR |
1868 | (*pos)++; |
1869 | ||
1870 | /* can't go backwards */ | |
1871 | if (iter->idx > i) | |
1872 | return NULL; | |
1873 | ||
1874 | if (iter->idx < 0) | |
955b61e5 | 1875 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1876 | else |
1877 | ent = iter; | |
1878 | ||
1879 | while (ent && iter->idx < i) | |
955b61e5 | 1880 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
1881 | |
1882 | iter->pos = *pos; | |
1883 | ||
bc0c38d1 SR |
1884 | return ent; |
1885 | } | |
1886 | ||
955b61e5 | 1887 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 SR |
1888 | { |
1889 | struct trace_array *tr = iter->tr; | |
1890 | struct ring_buffer_event *event; | |
1891 | struct ring_buffer_iter *buf_iter; | |
1892 | unsigned long entries = 0; | |
1893 | u64 ts; | |
1894 | ||
1895 | tr->data[cpu]->skipped_entries = 0; | |
1896 | ||
1897 | if (!iter->buffer_iter[cpu]) | |
1898 | return; | |
1899 | ||
1900 | buf_iter = iter->buffer_iter[cpu]; | |
1901 | ring_buffer_iter_reset(buf_iter); | |
1902 | ||
1903 | /* | |
1904 | * We could have the case with the max latency tracers | |
1905 | * that a reset never took place on a cpu. This is evident | |
1906 | * by the timestamp being before the start of the buffer. | |
1907 | */ | |
1908 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
1909 | if (ts >= iter->tr->time_start) | |
1910 | break; | |
1911 | entries++; | |
1912 | ring_buffer_read(buf_iter, NULL); | |
1913 | } | |
1914 | ||
1915 | tr->data[cpu]->skipped_entries = entries; | |
1916 | } | |
1917 | ||
d7350c3f | 1918 | /* |
d7350c3f FW |
1919 | * The current tracer is copied to avoid a global locking |
1920 | * all around. | |
1921 | */ | |
bc0c38d1 SR |
1922 | static void *s_start(struct seq_file *m, loff_t *pos) |
1923 | { | |
1924 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1925 | static struct tracer *old_tracer; |
b04cc6b1 | 1926 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1927 | void *p = NULL; |
1928 | loff_t l = 0; | |
3928a8a2 | 1929 | int cpu; |
bc0c38d1 | 1930 | |
d7350c3f | 1931 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1932 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1933 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1934 | old_tracer = current_trace; | |
1935 | *iter->trace = *current_trace; | |
d15f57f2 | 1936 | } |
d7350c3f | 1937 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1938 | |
1939 | atomic_inc(&trace_record_cmdline_disabled); | |
1940 | ||
bc0c38d1 SR |
1941 | if (*pos != iter->pos) { |
1942 | iter->ent = NULL; | |
1943 | iter->cpu = 0; | |
1944 | iter->idx = -1; | |
1945 | ||
d769041f SR |
1946 | ftrace_disable_cpu(); |
1947 | ||
b04cc6b1 FW |
1948 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1949 | for_each_tracing_cpu(cpu) | |
2f26ebd5 | 1950 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 1951 | } else |
2f26ebd5 | 1952 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 1953 | |
d769041f SR |
1954 | ftrace_enable_cpu(); |
1955 | ||
ac91d854 | 1956 | iter->leftover = 0; |
bc0c38d1 SR |
1957 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1958 | ; | |
1959 | ||
1960 | } else { | |
a63ce5b3 SR |
1961 | /* |
1962 | * If we overflowed the seq_file before, then we want | |
1963 | * to just reuse the trace_seq buffer again. | |
1964 | */ | |
1965 | if (iter->leftover) | |
1966 | p = iter; | |
1967 | else { | |
1968 | l = *pos - 1; | |
1969 | p = s_next(m, p, &l); | |
1970 | } | |
bc0c38d1 SR |
1971 | } |
1972 | ||
4f535968 | 1973 | trace_event_read_lock(); |
7e53bd42 | 1974 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
1975 | return p; |
1976 | } | |
1977 | ||
1978 | static void s_stop(struct seq_file *m, void *p) | |
1979 | { | |
7e53bd42 LJ |
1980 | struct trace_iterator *iter = m->private; |
1981 | ||
bc0c38d1 | 1982 | atomic_dec(&trace_record_cmdline_disabled); |
7e53bd42 | 1983 | trace_access_unlock(iter->cpu_file); |
4f535968 | 1984 | trace_event_read_unlock(); |
bc0c38d1 SR |
1985 | } |
1986 | ||
39eaf7ef SR |
1987 | static void |
1988 | get_total_entries(struct trace_array *tr, unsigned long *total, unsigned long *entries) | |
1989 | { | |
1990 | unsigned long count; | |
1991 | int cpu; | |
1992 | ||
1993 | *total = 0; | |
1994 | *entries = 0; | |
1995 | ||
1996 | for_each_tracing_cpu(cpu) { | |
1997 | count = ring_buffer_entries_cpu(tr->buffer, cpu); | |
1998 | /* | |
1999 | * If this buffer has skipped entries, then we hold all | |
2000 | * entries for the trace and we need to ignore the | |
2001 | * ones before the time stamp. | |
2002 | */ | |
2003 | if (tr->data[cpu]->skipped_entries) { | |
2004 | count -= tr->data[cpu]->skipped_entries; | |
2005 | /* total is the same as the entries */ | |
2006 | *total += count; | |
2007 | } else | |
2008 | *total += count + | |
2009 | ring_buffer_overrun_cpu(tr->buffer, cpu); | |
2010 | *entries += count; | |
2011 | } | |
2012 | } | |
2013 | ||
e309b41d | 2014 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2015 | { |
a6168353 ME |
2016 | seq_puts(m, "# _------=> CPU# \n"); |
2017 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
2018 | seq_puts(m, "# | / _----=> need-resched \n"); | |
2019 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
2020 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
e6e1e259 SR |
2021 | seq_puts(m, "# |||| / delay \n"); |
2022 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
2023 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2024 | } |
2025 | ||
39eaf7ef | 2026 | static void print_event_info(struct trace_array *tr, struct seq_file *m) |
bc0c38d1 | 2027 | { |
39eaf7ef SR |
2028 | unsigned long total; |
2029 | unsigned long entries; | |
2030 | ||
2031 | get_total_entries(tr, &total, &entries); | |
2032 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", | |
2033 | entries, total, num_online_cpus()); | |
2034 | seq_puts(m, "#\n"); | |
2035 | } | |
2036 | ||
2037 | static void print_func_help_header(struct trace_array *tr, struct seq_file *m) | |
2038 | { | |
2039 | print_event_info(tr, m); | |
77271ce4 | 2040 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
a6168353 | 2041 | seq_puts(m, "# | | | | |\n"); |
bc0c38d1 SR |
2042 | } |
2043 | ||
39eaf7ef | 2044 | static void print_func_help_header_irq(struct trace_array *tr, struct seq_file *m) |
77271ce4 | 2045 | { |
39eaf7ef | 2046 | print_event_info(tr, m); |
77271ce4 SR |
2047 | seq_puts(m, "# _-----=> irqs-off\n"); |
2048 | seq_puts(m, "# / _----=> need-resched\n"); | |
2049 | seq_puts(m, "# | / _---=> hardirq/softirq\n"); | |
2050 | seq_puts(m, "# || / _--=> preempt-depth\n"); | |
2051 | seq_puts(m, "# ||| / delay\n"); | |
2052 | seq_puts(m, "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n"); | |
2053 | seq_puts(m, "# | | | |||| | |\n"); | |
2054 | } | |
bc0c38d1 | 2055 | |
62b915f1 | 2056 | void |
bc0c38d1 SR |
2057 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2058 | { | |
2059 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
2060 | struct trace_array *tr = iter->tr; | |
2061 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
2062 | struct tracer *type = current_trace; | |
39eaf7ef SR |
2063 | unsigned long entries; |
2064 | unsigned long total; | |
bc0c38d1 SR |
2065 | const char *name = "preemption"; |
2066 | ||
2067 | if (type) | |
2068 | name = type->name; | |
2069 | ||
39eaf7ef | 2070 | get_total_entries(tr, &total, &entries); |
bc0c38d1 | 2071 | |
888b55dc | 2072 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2073 | name, UTS_RELEASE); |
888b55dc | 2074 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2075 | "---------------------------------\n"); |
888b55dc | 2076 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2077 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2078 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2079 | entries, |
4c11d7ae | 2080 | total, |
bc0c38d1 SR |
2081 | tr->cpu, |
2082 | #if defined(CONFIG_PREEMPT_NONE) | |
2083 | "server", | |
2084 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2085 | "desktop", | |
b5c21b45 | 2086 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2087 | "preempt", |
2088 | #else | |
2089 | "unknown", | |
2090 | #endif | |
2091 | /* These are reserved for later use */ | |
2092 | 0, 0, 0, 0); | |
2093 | #ifdef CONFIG_SMP | |
2094 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2095 | #else | |
2096 | seq_puts(m, ")\n"); | |
2097 | #endif | |
888b55dc KM |
2098 | seq_puts(m, "# -----------------\n"); |
2099 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
2100 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
2101 | data->comm, data->pid, data->uid, data->nice, | |
2102 | data->policy, data->rt_priority); | |
888b55dc | 2103 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2104 | |
2105 | if (data->critical_start) { | |
888b55dc | 2106 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2107 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2108 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2109 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2110 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2111 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2112 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2113 | } |
2114 | ||
888b55dc | 2115 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2116 | } |
2117 | ||
a309720c SR |
2118 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2119 | { | |
2120 | struct trace_seq *s = &iter->seq; | |
2121 | ||
12ef7d44 SR |
2122 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
2123 | return; | |
2124 | ||
2125 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
2126 | return; | |
2127 | ||
4462344e | 2128 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
2129 | return; |
2130 | ||
2f26ebd5 SR |
2131 | if (iter->tr->data[iter->cpu]->skipped_entries) |
2132 | return; | |
2133 | ||
4462344e | 2134 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
2135 | |
2136 | /* Don't print started cpu buffer for the first entry of the trace */ | |
2137 | if (iter->idx > 1) | |
2138 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
2139 | iter->cpu); | |
a309720c SR |
2140 | } |
2141 | ||
2c4f035f | 2142 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 2143 | { |
214023c3 | 2144 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 2145 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 2146 | struct trace_entry *entry; |
f633cef0 | 2147 | struct trace_event *event; |
bc0c38d1 | 2148 | |
4e3c3333 | 2149 | entry = iter->ent; |
dd0e545f | 2150 | |
a309720c SR |
2151 | test_cpu_buff_start(iter); |
2152 | ||
c4a8e8be | 2153 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 2154 | |
c4a8e8be | 2155 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
2156 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2157 | if (!trace_print_lat_context(iter)) | |
2158 | goto partial; | |
2159 | } else { | |
2160 | if (!trace_print_context(iter)) | |
2161 | goto partial; | |
2162 | } | |
c4a8e8be | 2163 | } |
bc0c38d1 | 2164 | |
268ccda0 | 2165 | if (event) |
a9a57763 | 2166 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 ACM |
2167 | |
2168 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
2169 | goto partial; | |
02b67518 | 2170 | |
2c4f035f | 2171 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2172 | partial: |
2173 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
2174 | } |
2175 | ||
2c4f035f | 2176 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
2177 | { |
2178 | struct trace_seq *s = &iter->seq; | |
2179 | struct trace_entry *entry; | |
f633cef0 | 2180 | struct trace_event *event; |
f9896bf3 IM |
2181 | |
2182 | entry = iter->ent; | |
dd0e545f | 2183 | |
c4a8e8be | 2184 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
2185 | if (!trace_seq_printf(s, "%d %d %llu ", |
2186 | entry->pid, iter->cpu, iter->ts)) | |
2187 | goto partial; | |
c4a8e8be | 2188 | } |
f9896bf3 | 2189 | |
f633cef0 | 2190 | event = ftrace_find_event(entry->type); |
268ccda0 | 2191 | if (event) |
a9a57763 | 2192 | return event->funcs->raw(iter, 0, event); |
d9793bd8 ACM |
2193 | |
2194 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
2195 | goto partial; | |
777e208d | 2196 | |
2c4f035f | 2197 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
2198 | partial: |
2199 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
2200 | } |
2201 | ||
2c4f035f | 2202 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
2203 | { |
2204 | struct trace_seq *s = &iter->seq; | |
2205 | unsigned char newline = '\n'; | |
2206 | struct trace_entry *entry; | |
f633cef0 | 2207 | struct trace_event *event; |
5e3ca0ec IM |
2208 | |
2209 | entry = iter->ent; | |
dd0e545f | 2210 | |
c4a8e8be FW |
2211 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2212 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
2213 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
2214 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
2215 | } | |
5e3ca0ec | 2216 | |
f633cef0 | 2217 | event = ftrace_find_event(entry->type); |
268ccda0 | 2218 | if (event) { |
a9a57763 | 2219 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
2220 | if (ret != TRACE_TYPE_HANDLED) |
2221 | return ret; | |
2222 | } | |
7104f300 | 2223 | |
5e3ca0ec IM |
2224 | SEQ_PUT_FIELD_RET(s, newline); |
2225 | ||
2c4f035f | 2226 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
2227 | } |
2228 | ||
2c4f035f | 2229 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
2230 | { |
2231 | struct trace_seq *s = &iter->seq; | |
2232 | struct trace_entry *entry; | |
f633cef0 | 2233 | struct trace_event *event; |
cb0f12aa IM |
2234 | |
2235 | entry = iter->ent; | |
dd0e545f | 2236 | |
c4a8e8be FW |
2237 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
2238 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 2239 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
2240 | SEQ_PUT_FIELD_RET(s, iter->ts); |
2241 | } | |
cb0f12aa | 2242 | |
f633cef0 | 2243 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
2244 | return event ? event->funcs->binary(iter, 0, event) : |
2245 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
2246 | } |
2247 | ||
62b915f1 | 2248 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 2249 | { |
bc0c38d1 SR |
2250 | int cpu; |
2251 | ||
9aba60fe SR |
2252 | /* If we are looking at one CPU buffer, only check that one */ |
2253 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
2254 | cpu = iter->cpu_file; | |
2255 | if (iter->buffer_iter[cpu]) { | |
2256 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
2257 | return 0; | |
2258 | } else { | |
2259 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
2260 | return 0; | |
2261 | } | |
2262 | return 1; | |
2263 | } | |
2264 | ||
ab46428c | 2265 | for_each_tracing_cpu(cpu) { |
d769041f SR |
2266 | if (iter->buffer_iter[cpu]) { |
2267 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
2268 | return 0; | |
2269 | } else { | |
2270 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
2271 | return 0; | |
2272 | } | |
bc0c38d1 | 2273 | } |
d769041f | 2274 | |
797d3712 | 2275 | return 1; |
bc0c38d1 SR |
2276 | } |
2277 | ||
4f535968 | 2278 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 2279 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 2280 | { |
2c4f035f FW |
2281 | enum print_line_t ret; |
2282 | ||
ee5e51f5 JO |
2283 | if (iter->lost_events && |
2284 | !trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
2285 | iter->cpu, iter->lost_events)) | |
2286 | return TRACE_TYPE_PARTIAL_LINE; | |
bc21b478 | 2287 | |
2c4f035f FW |
2288 | if (iter->trace && iter->trace->print_line) { |
2289 | ret = iter->trace->print_line(iter); | |
2290 | if (ret != TRACE_TYPE_UNHANDLED) | |
2291 | return ret; | |
2292 | } | |
72829bc3 | 2293 | |
48ead020 FW |
2294 | if (iter->ent->type == TRACE_BPRINT && |
2295 | trace_flags & TRACE_ITER_PRINTK && | |
2296 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2297 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 2298 | |
66896a85 FW |
2299 | if (iter->ent->type == TRACE_PRINT && |
2300 | trace_flags & TRACE_ITER_PRINTK && | |
2301 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 2302 | return trace_print_printk_msg_only(iter); |
66896a85 | 2303 | |
cb0f12aa IM |
2304 | if (trace_flags & TRACE_ITER_BIN) |
2305 | return print_bin_fmt(iter); | |
2306 | ||
5e3ca0ec IM |
2307 | if (trace_flags & TRACE_ITER_HEX) |
2308 | return print_hex_fmt(iter); | |
2309 | ||
f9896bf3 IM |
2310 | if (trace_flags & TRACE_ITER_RAW) |
2311 | return print_raw_fmt(iter); | |
2312 | ||
f9896bf3 IM |
2313 | return print_trace_fmt(iter); |
2314 | } | |
2315 | ||
7e9a49ef JO |
2316 | void trace_latency_header(struct seq_file *m) |
2317 | { | |
2318 | struct trace_iterator *iter = m->private; | |
2319 | ||
2320 | /* print nothing if the buffers are empty */ | |
2321 | if (trace_empty(iter)) | |
2322 | return; | |
2323 | ||
2324 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
2325 | print_trace_header(m, iter); | |
2326 | ||
2327 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2328 | print_lat_help_header(m); | |
2329 | } | |
2330 | ||
62b915f1 JO |
2331 | void trace_default_header(struct seq_file *m) |
2332 | { | |
2333 | struct trace_iterator *iter = m->private; | |
2334 | ||
f56e7f8e JO |
2335 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
2336 | return; | |
2337 | ||
62b915f1 JO |
2338 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
2339 | /* print nothing if the buffers are empty */ | |
2340 | if (trace_empty(iter)) | |
2341 | return; | |
2342 | print_trace_header(m, iter); | |
2343 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2344 | print_lat_help_header(m); | |
2345 | } else { | |
77271ce4 SR |
2346 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
2347 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
39eaf7ef | 2348 | print_func_help_header_irq(iter->tr, m); |
77271ce4 | 2349 | else |
39eaf7ef | 2350 | print_func_help_header(iter->tr, m); |
77271ce4 | 2351 | } |
62b915f1 JO |
2352 | } |
2353 | } | |
2354 | ||
e0a413f6 SR |
2355 | static void test_ftrace_alive(struct seq_file *m) |
2356 | { | |
2357 | if (!ftrace_is_dead()) | |
2358 | return; | |
2359 | seq_printf(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
2360 | seq_printf(m, "# MAY BE MISSING FUNCTION EVENTS\n"); | |
2361 | } | |
2362 | ||
bc0c38d1 SR |
2363 | static int s_show(struct seq_file *m, void *v) |
2364 | { | |
2365 | struct trace_iterator *iter = v; | |
a63ce5b3 | 2366 | int ret; |
bc0c38d1 SR |
2367 | |
2368 | if (iter->ent == NULL) { | |
2369 | if (iter->tr) { | |
2370 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
2371 | seq_puts(m, "#\n"); | |
e0a413f6 | 2372 | test_ftrace_alive(m); |
bc0c38d1 | 2373 | } |
8bba1bf5 MM |
2374 | if (iter->trace && iter->trace->print_header) |
2375 | iter->trace->print_header(m); | |
62b915f1 JO |
2376 | else |
2377 | trace_default_header(m); | |
2378 | ||
a63ce5b3 SR |
2379 | } else if (iter->leftover) { |
2380 | /* | |
2381 | * If we filled the seq_file buffer earlier, we | |
2382 | * want to just show it now. | |
2383 | */ | |
2384 | ret = trace_print_seq(m, &iter->seq); | |
2385 | ||
2386 | /* ret should this time be zero, but you never know */ | |
2387 | iter->leftover = ret; | |
2388 | ||
bc0c38d1 | 2389 | } else { |
f9896bf3 | 2390 | print_trace_line(iter); |
a63ce5b3 SR |
2391 | ret = trace_print_seq(m, &iter->seq); |
2392 | /* | |
2393 | * If we overflow the seq_file buffer, then it will | |
2394 | * ask us for this data again at start up. | |
2395 | * Use that instead. | |
2396 | * ret is 0 if seq_file write succeeded. | |
2397 | * -1 otherwise. | |
2398 | */ | |
2399 | iter->leftover = ret; | |
bc0c38d1 SR |
2400 | } |
2401 | ||
2402 | return 0; | |
2403 | } | |
2404 | ||
88e9d34c | 2405 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
2406 | .start = s_start, |
2407 | .next = s_next, | |
2408 | .stop = s_stop, | |
2409 | .show = s_show, | |
bc0c38d1 SR |
2410 | }; |
2411 | ||
e309b41d | 2412 | static struct trace_iterator * |
85a2f9b4 | 2413 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 2414 | { |
b04cc6b1 | 2415 | long cpu_file = (long) inode->i_private; |
bc0c38d1 | 2416 | struct trace_iterator *iter; |
50e18b94 | 2417 | int cpu; |
bc0c38d1 | 2418 | |
85a2f9b4 SR |
2419 | if (tracing_disabled) |
2420 | return ERR_PTR(-ENODEV); | |
60a11774 | 2421 | |
50e18b94 | 2422 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
2423 | if (!iter) |
2424 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 2425 | |
d7350c3f FW |
2426 | /* |
2427 | * We make a copy of the current tracer to avoid concurrent | |
2428 | * changes on it while we are reading. | |
2429 | */ | |
bc0c38d1 | 2430 | mutex_lock(&trace_types_lock); |
d7350c3f | 2431 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 2432 | if (!iter->trace) |
d7350c3f | 2433 | goto fail; |
85a2f9b4 | 2434 | |
d7350c3f FW |
2435 | if (current_trace) |
2436 | *iter->trace = *current_trace; | |
2437 | ||
79f55997 | 2438 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
2439 | goto fail; |
2440 | ||
bc0c38d1 SR |
2441 | if (current_trace && current_trace->print_max) |
2442 | iter->tr = &max_tr; | |
2443 | else | |
b04cc6b1 | 2444 | iter->tr = &global_trace; |
bc0c38d1 | 2445 | iter->pos = -1; |
d7350c3f | 2446 | mutex_init(&iter->mutex); |
b04cc6b1 | 2447 | iter->cpu_file = cpu_file; |
bc0c38d1 | 2448 | |
8bba1bf5 MM |
2449 | /* Notify the tracer early; before we stop tracing. */ |
2450 | if (iter->trace && iter->trace->open) | |
a93751ca | 2451 | iter->trace->open(iter); |
8bba1bf5 | 2452 | |
12ef7d44 SR |
2453 | /* Annotate start of buffers if we had overruns */ |
2454 | if (ring_buffer_overruns(iter->tr->buffer)) | |
2455 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
2456 | ||
2f26ebd5 SR |
2457 | /* stop the trace while dumping */ |
2458 | tracing_stop(); | |
2459 | ||
b04cc6b1 FW |
2460 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
2461 | for_each_tracing_cpu(cpu) { | |
b04cc6b1 | 2462 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2463 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2464 | } | |
2465 | ring_buffer_read_prepare_sync(); | |
2466 | for_each_tracing_cpu(cpu) { | |
2467 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2468 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
2469 | } |
2470 | } else { | |
2471 | cpu = iter->cpu_file; | |
3928a8a2 | 2472 | iter->buffer_iter[cpu] = |
72c9ddfd DM |
2473 | ring_buffer_read_prepare(iter->tr->buffer, cpu); |
2474 | ring_buffer_read_prepare_sync(); | |
2475 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 2476 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
2477 | } |
2478 | ||
bc0c38d1 SR |
2479 | mutex_unlock(&trace_types_lock); |
2480 | ||
bc0c38d1 | 2481 | return iter; |
3928a8a2 | 2482 | |
d7350c3f | 2483 | fail: |
3928a8a2 | 2484 | mutex_unlock(&trace_types_lock); |
d7350c3f | 2485 | kfree(iter->trace); |
50e18b94 JO |
2486 | seq_release_private(inode, file); |
2487 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
2488 | } |
2489 | ||
2490 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2491 | { | |
60a11774 SR |
2492 | if (tracing_disabled) |
2493 | return -ENODEV; | |
2494 | ||
bc0c38d1 SR |
2495 | filp->private_data = inode->i_private; |
2496 | return 0; | |
2497 | } | |
2498 | ||
4fd27358 | 2499 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 2500 | { |
907f2784 | 2501 | struct seq_file *m = file->private_data; |
4acd4d00 | 2502 | struct trace_iterator *iter; |
3928a8a2 | 2503 | int cpu; |
bc0c38d1 | 2504 | |
4acd4d00 SR |
2505 | if (!(file->f_mode & FMODE_READ)) |
2506 | return 0; | |
2507 | ||
2508 | iter = m->private; | |
2509 | ||
bc0c38d1 | 2510 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
2511 | for_each_tracing_cpu(cpu) { |
2512 | if (iter->buffer_iter[cpu]) | |
2513 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2514 | } | |
2515 | ||
bc0c38d1 SR |
2516 | if (iter->trace && iter->trace->close) |
2517 | iter->trace->close(iter); | |
2518 | ||
2519 | /* reenable tracing if it was previously enabled */ | |
9036990d | 2520 | tracing_start(); |
bc0c38d1 SR |
2521 | mutex_unlock(&trace_types_lock); |
2522 | ||
d7350c3f | 2523 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2524 | free_cpumask_var(iter->started); |
d7350c3f | 2525 | kfree(iter->trace); |
50e18b94 | 2526 | seq_release_private(inode, file); |
bc0c38d1 SR |
2527 | return 0; |
2528 | } | |
2529 | ||
2530 | static int tracing_open(struct inode *inode, struct file *file) | |
2531 | { | |
85a2f9b4 SR |
2532 | struct trace_iterator *iter; |
2533 | int ret = 0; | |
bc0c38d1 | 2534 | |
4acd4d00 SR |
2535 | /* If this file was open for write, then erase contents */ |
2536 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2537 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 2538 | long cpu = (long) inode->i_private; |
bc0c38d1 | 2539 | |
4acd4d00 SR |
2540 | if (cpu == TRACE_PIPE_ALL_CPU) |
2541 | tracing_reset_online_cpus(&global_trace); | |
2542 | else | |
2543 | tracing_reset(&global_trace, cpu); | |
2544 | } | |
bc0c38d1 | 2545 | |
4acd4d00 SR |
2546 | if (file->f_mode & FMODE_READ) { |
2547 | iter = __tracing_open(inode, file); | |
2548 | if (IS_ERR(iter)) | |
2549 | ret = PTR_ERR(iter); | |
2550 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2551 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2552 | } | |
bc0c38d1 SR |
2553 | return ret; |
2554 | } | |
2555 | ||
e309b41d | 2556 | static void * |
bc0c38d1 SR |
2557 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2558 | { | |
f129e965 | 2559 | struct tracer *t = v; |
bc0c38d1 SR |
2560 | |
2561 | (*pos)++; | |
2562 | ||
2563 | if (t) | |
2564 | t = t->next; | |
2565 | ||
bc0c38d1 SR |
2566 | return t; |
2567 | } | |
2568 | ||
2569 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2570 | { | |
f129e965 | 2571 | struct tracer *t; |
bc0c38d1 SR |
2572 | loff_t l = 0; |
2573 | ||
2574 | mutex_lock(&trace_types_lock); | |
f129e965 | 2575 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2576 | ; |
2577 | ||
2578 | return t; | |
2579 | } | |
2580 | ||
2581 | static void t_stop(struct seq_file *m, void *p) | |
2582 | { | |
2583 | mutex_unlock(&trace_types_lock); | |
2584 | } | |
2585 | ||
2586 | static int t_show(struct seq_file *m, void *v) | |
2587 | { | |
2588 | struct tracer *t = v; | |
2589 | ||
2590 | if (!t) | |
2591 | return 0; | |
2592 | ||
2593 | seq_printf(m, "%s", t->name); | |
2594 | if (t->next) | |
2595 | seq_putc(m, ' '); | |
2596 | else | |
2597 | seq_putc(m, '\n'); | |
2598 | ||
2599 | return 0; | |
2600 | } | |
2601 | ||
88e9d34c | 2602 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
2603 | .start = t_start, |
2604 | .next = t_next, | |
2605 | .stop = t_stop, | |
2606 | .show = t_show, | |
bc0c38d1 SR |
2607 | }; |
2608 | ||
2609 | static int show_traces_open(struct inode *inode, struct file *file) | |
2610 | { | |
60a11774 SR |
2611 | if (tracing_disabled) |
2612 | return -ENODEV; | |
2613 | ||
f129e965 | 2614 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2615 | } |
2616 | ||
4acd4d00 SR |
2617 | static ssize_t |
2618 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2619 | size_t count, loff_t *ppos) | |
2620 | { | |
2621 | return count; | |
2622 | } | |
2623 | ||
364829b1 SP |
2624 | static loff_t tracing_seek(struct file *file, loff_t offset, int origin) |
2625 | { | |
2626 | if (file->f_mode & FMODE_READ) | |
2627 | return seq_lseek(file, offset, origin); | |
2628 | else | |
2629 | return 0; | |
2630 | } | |
2631 | ||
5e2336a0 | 2632 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2633 | .open = tracing_open, |
2634 | .read = seq_read, | |
4acd4d00 | 2635 | .write = tracing_write_stub, |
364829b1 | 2636 | .llseek = tracing_seek, |
4bf39a94 | 2637 | .release = tracing_release, |
bc0c38d1 SR |
2638 | }; |
2639 | ||
5e2336a0 | 2640 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2641 | .open = show_traces_open, |
2642 | .read = seq_read, | |
2643 | .release = seq_release, | |
b444786f | 2644 | .llseek = seq_lseek, |
c7078de1 IM |
2645 | }; |
2646 | ||
36dfe925 IM |
2647 | /* |
2648 | * Only trace on a CPU if the bitmask is set: | |
2649 | */ | |
9e01c1b7 | 2650 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2651 | |
2652 | /* | |
2653 | * The tracer itself will not take this lock, but still we want | |
2654 | * to provide a consistent cpumask to user-space: | |
2655 | */ | |
2656 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2657 | ||
2658 | /* | |
2659 | * Temporary storage for the character representation of the | |
2660 | * CPU bitmask (and one more byte for the newline): | |
2661 | */ | |
2662 | static char mask_str[NR_CPUS + 1]; | |
2663 | ||
c7078de1 IM |
2664 | static ssize_t |
2665 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2666 | size_t count, loff_t *ppos) | |
2667 | { | |
36dfe925 | 2668 | int len; |
c7078de1 IM |
2669 | |
2670 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2671 | |
9e01c1b7 | 2672 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2673 | if (count - len < 2) { |
2674 | count = -EINVAL; | |
2675 | goto out_err; | |
2676 | } | |
2677 | len += sprintf(mask_str + len, "\n"); | |
2678 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2679 | ||
2680 | out_err: | |
c7078de1 IM |
2681 | mutex_unlock(&tracing_cpumask_update_lock); |
2682 | ||
2683 | return count; | |
2684 | } | |
2685 | ||
2686 | static ssize_t | |
2687 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2688 | size_t count, loff_t *ppos) | |
2689 | { | |
36dfe925 | 2690 | int err, cpu; |
9e01c1b7 RR |
2691 | cpumask_var_t tracing_cpumask_new; |
2692 | ||
2693 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2694 | return -ENOMEM; | |
c7078de1 | 2695 | |
9e01c1b7 | 2696 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2697 | if (err) |
36dfe925 IM |
2698 | goto err_unlock; |
2699 | ||
215368e8 LZ |
2700 | mutex_lock(&tracing_cpumask_update_lock); |
2701 | ||
a5e25883 | 2702 | local_irq_disable(); |
0199c4e6 | 2703 | arch_spin_lock(&ftrace_max_lock); |
ab46428c | 2704 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2705 | /* |
2706 | * Increase/decrease the disabled counter if we are | |
2707 | * about to flip a bit in the cpumask: | |
2708 | */ | |
9e01c1b7 RR |
2709 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2710 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2711 | atomic_inc(&global_trace.data[cpu]->disabled); |
2712 | } | |
9e01c1b7 RR |
2713 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2714 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2715 | atomic_dec(&global_trace.data[cpu]->disabled); |
2716 | } | |
2717 | } | |
0199c4e6 | 2718 | arch_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2719 | local_irq_enable(); |
36dfe925 | 2720 | |
9e01c1b7 | 2721 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2722 | |
2723 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2724 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2725 | |
2726 | return count; | |
36dfe925 IM |
2727 | |
2728 | err_unlock: | |
215368e8 | 2729 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2730 | |
2731 | return err; | |
c7078de1 IM |
2732 | } |
2733 | ||
5e2336a0 | 2734 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2735 | .open = tracing_open_generic, |
2736 | .read = tracing_cpumask_read, | |
2737 | .write = tracing_cpumask_write, | |
b444786f | 2738 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
2739 | }; |
2740 | ||
fdb372ed | 2741 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 2742 | { |
d8e83d26 SR |
2743 | struct tracer_opt *trace_opts; |
2744 | u32 tracer_flags; | |
d8e83d26 | 2745 | int i; |
adf9f195 | 2746 | |
d8e83d26 SR |
2747 | mutex_lock(&trace_types_lock); |
2748 | tracer_flags = current_trace->flags->val; | |
2749 | trace_opts = current_trace->flags->opts; | |
2750 | ||
bc0c38d1 SR |
2751 | for (i = 0; trace_options[i]; i++) { |
2752 | if (trace_flags & (1 << i)) | |
fdb372ed | 2753 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 2754 | else |
fdb372ed | 2755 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2756 | } |
2757 | ||
adf9f195 FW |
2758 | for (i = 0; trace_opts[i].name; i++) { |
2759 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 2760 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 2761 | else |
fdb372ed | 2762 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 2763 | } |
d8e83d26 | 2764 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2765 | |
fdb372ed | 2766 | return 0; |
bc0c38d1 | 2767 | } |
bc0c38d1 | 2768 | |
8d18eaaf LZ |
2769 | static int __set_tracer_option(struct tracer *trace, |
2770 | struct tracer_flags *tracer_flags, | |
2771 | struct tracer_opt *opts, int neg) | |
2772 | { | |
2773 | int ret; | |
bc0c38d1 | 2774 | |
8d18eaaf LZ |
2775 | ret = trace->set_flag(tracer_flags->val, opts->bit, !neg); |
2776 | if (ret) | |
2777 | return ret; | |
2778 | ||
2779 | if (neg) | |
2780 | tracer_flags->val &= ~opts->bit; | |
2781 | else | |
2782 | tracer_flags->val |= opts->bit; | |
2783 | return 0; | |
bc0c38d1 SR |
2784 | } |
2785 | ||
adf9f195 FW |
2786 | /* Try to assign a tracer specific option */ |
2787 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2788 | { | |
7770841e | 2789 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 2790 | struct tracer_opt *opts = NULL; |
8d18eaaf | 2791 | int i; |
adf9f195 | 2792 | |
7770841e Z |
2793 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2794 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 2795 | |
8d18eaaf LZ |
2796 | if (strcmp(cmp, opts->name) == 0) |
2797 | return __set_tracer_option(trace, trace->flags, | |
2798 | opts, neg); | |
adf9f195 | 2799 | } |
adf9f195 | 2800 | |
8d18eaaf | 2801 | return -EINVAL; |
adf9f195 FW |
2802 | } |
2803 | ||
af4617bd SR |
2804 | static void set_tracer_flags(unsigned int mask, int enabled) |
2805 | { | |
2806 | /* do nothing if flag is already set */ | |
2807 | if (!!(trace_flags & mask) == !!enabled) | |
2808 | return; | |
2809 | ||
2810 | if (enabled) | |
2811 | trace_flags |= mask; | |
2812 | else | |
2813 | trace_flags &= ~mask; | |
e870e9a1 LZ |
2814 | |
2815 | if (mask == TRACE_ITER_RECORD_CMD) | |
2816 | trace_event_enable_cmd_record(enabled); | |
750912fa DS |
2817 | |
2818 | if (mask == TRACE_ITER_OVERWRITE) | |
2819 | ring_buffer_change_overwrite(global_trace.buffer, enabled); | |
af4617bd SR |
2820 | } |
2821 | ||
bc0c38d1 | 2822 | static ssize_t |
ee6bce52 | 2823 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2824 | size_t cnt, loff_t *ppos) |
2825 | { | |
2826 | char buf[64]; | |
8d18eaaf | 2827 | char *cmp; |
bc0c38d1 | 2828 | int neg = 0; |
adf9f195 | 2829 | int ret; |
bc0c38d1 SR |
2830 | int i; |
2831 | ||
cffae437 SR |
2832 | if (cnt >= sizeof(buf)) |
2833 | return -EINVAL; | |
bc0c38d1 SR |
2834 | |
2835 | if (copy_from_user(&buf, ubuf, cnt)) | |
2836 | return -EFAULT; | |
2837 | ||
2838 | buf[cnt] = 0; | |
8d18eaaf | 2839 | cmp = strstrip(buf); |
bc0c38d1 | 2840 | |
8d18eaaf | 2841 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
2842 | neg = 1; |
2843 | cmp += 2; | |
2844 | } | |
2845 | ||
2846 | for (i = 0; trace_options[i]; i++) { | |
8d18eaaf | 2847 | if (strcmp(cmp, trace_options[i]) == 0) { |
af4617bd | 2848 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2849 | break; |
2850 | } | |
2851 | } | |
adf9f195 FW |
2852 | |
2853 | /* If no option could be set, test the specific tracer options */ | |
2854 | if (!trace_options[i]) { | |
d8e83d26 | 2855 | mutex_lock(&trace_types_lock); |
adf9f195 | 2856 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2857 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2858 | if (ret) |
2859 | return ret; | |
2860 | } | |
bc0c38d1 | 2861 | |
cf8517cf | 2862 | *ppos += cnt; |
bc0c38d1 SR |
2863 | |
2864 | return cnt; | |
2865 | } | |
2866 | ||
fdb372ed LZ |
2867 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
2868 | { | |
2869 | if (tracing_disabled) | |
2870 | return -ENODEV; | |
2871 | return single_open(file, tracing_trace_options_show, NULL); | |
2872 | } | |
2873 | ||
5e2336a0 | 2874 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
2875 | .open = tracing_trace_options_open, |
2876 | .read = seq_read, | |
2877 | .llseek = seq_lseek, | |
2878 | .release = single_release, | |
ee6bce52 | 2879 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
2880 | }; |
2881 | ||
7bd2f24c IM |
2882 | static const char readme_msg[] = |
2883 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2884 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2885 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
1e42e83f | 2886 | "wakeup wakeup_rt preemptirqsoff preemptoff irqsoff function nop\n\n" |
156f5a78 | 2887 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2888 | "nop\n" |
1e42e83f | 2889 | "# echo wakeup > /sys/kernel/debug/tracing/current_tracer\n" |
156f5a78 | 2890 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
1e42e83f | 2891 | "wakeup\n" |
156f5a78 | 2892 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2893 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 | 2894 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
9b5f8b31 | 2895 | "# echo 1 > /sys/kernel/debug/tracing/tracing_on\n" |
156f5a78 | 2896 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" |
9b5f8b31 | 2897 | "# echo 0 > /sys/kernel/debug/tracing/tracing_on\n" |
7bd2f24c IM |
2898 | ; |
2899 | ||
2900 | static ssize_t | |
2901 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2902 | size_t cnt, loff_t *ppos) | |
2903 | { | |
2904 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2905 | readme_msg, strlen(readme_msg)); | |
2906 | } | |
2907 | ||
5e2336a0 | 2908 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2909 | .open = tracing_open_generic, |
2910 | .read = tracing_readme_read, | |
b444786f | 2911 | .llseek = generic_file_llseek, |
7bd2f24c IM |
2912 | }; |
2913 | ||
69abe6a5 AP |
2914 | static ssize_t |
2915 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2916 | size_t cnt, loff_t *ppos) | |
2917 | { | |
2918 | char *buf_comm; | |
2919 | char *file_buf; | |
2920 | char *buf; | |
2921 | int len = 0; | |
2922 | int pid; | |
2923 | int i; | |
2924 | ||
2925 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2926 | if (!file_buf) | |
2927 | return -ENOMEM; | |
2928 | ||
2929 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2930 | if (!buf_comm) { | |
2931 | kfree(file_buf); | |
2932 | return -ENOMEM; | |
2933 | } | |
2934 | ||
2935 | buf = file_buf; | |
2936 | ||
2937 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2938 | int r; | |
2939 | ||
2940 | pid = map_cmdline_to_pid[i]; | |
2941 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2942 | continue; | |
2943 | ||
2944 | trace_find_cmdline(pid, buf_comm); | |
2945 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2946 | buf += r; | |
2947 | len += r; | |
2948 | } | |
2949 | ||
2950 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2951 | file_buf, len); | |
2952 | ||
2953 | kfree(file_buf); | |
2954 | kfree(buf_comm); | |
2955 | ||
2956 | return len; | |
2957 | } | |
2958 | ||
2959 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2960 | .open = tracing_open_generic, | |
2961 | .read = tracing_saved_cmdlines_read, | |
b444786f | 2962 | .llseek = generic_file_llseek, |
69abe6a5 AP |
2963 | }; |
2964 | ||
bc0c38d1 SR |
2965 | static ssize_t |
2966 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2967 | size_t cnt, loff_t *ppos) | |
2968 | { | |
bc0c38d1 SR |
2969 | char buf[64]; |
2970 | int r; | |
2971 | ||
9036990d | 2972 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2973 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2974 | } |
2975 | ||
2976 | static ssize_t | |
2977 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2978 | size_t cnt, loff_t *ppos) | |
2979 | { | |
2980 | struct trace_array *tr = filp->private_data; | |
5e39841c | 2981 | unsigned long val; |
c6caeeb1 | 2982 | int ret; |
bc0c38d1 | 2983 | |
22fe9b54 PH |
2984 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
2985 | if (ret) | |
c6caeeb1 | 2986 | return ret; |
bc0c38d1 SR |
2987 | |
2988 | val = !!val; | |
2989 | ||
2990 | mutex_lock(&trace_types_lock); | |
9036990d | 2991 | if (tracer_enabled ^ val) { |
6752ab4a SR |
2992 | |
2993 | /* Only need to warn if this is used to change the state */ | |
2994 | WARN_ONCE(1, "tracing_enabled is deprecated. Use tracing_on"); | |
2995 | ||
9036990d | 2996 | if (val) { |
bc0c38d1 | 2997 | tracer_enabled = 1; |
9036990d SR |
2998 | if (current_trace->start) |
2999 | current_trace->start(tr); | |
3000 | tracing_start(); | |
3001 | } else { | |
bc0c38d1 | 3002 | tracer_enabled = 0; |
9036990d SR |
3003 | tracing_stop(); |
3004 | if (current_trace->stop) | |
3005 | current_trace->stop(tr); | |
3006 | } | |
bc0c38d1 SR |
3007 | } |
3008 | mutex_unlock(&trace_types_lock); | |
3009 | ||
cf8517cf | 3010 | *ppos += cnt; |
bc0c38d1 SR |
3011 | |
3012 | return cnt; | |
3013 | } | |
3014 | ||
3015 | static ssize_t | |
3016 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
3017 | size_t cnt, loff_t *ppos) | |
3018 | { | |
ee6c2c1b | 3019 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
3020 | int r; |
3021 | ||
3022 | mutex_lock(&trace_types_lock); | |
3023 | if (current_trace) | |
3024 | r = sprintf(buf, "%s\n", current_trace->name); | |
3025 | else | |
3026 | r = sprintf(buf, "\n"); | |
3027 | mutex_unlock(&trace_types_lock); | |
3028 | ||
4bf39a94 | 3029 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3030 | } |
3031 | ||
b6f11df2 ACM |
3032 | int tracer_init(struct tracer *t, struct trace_array *tr) |
3033 | { | |
3034 | tracing_reset_online_cpus(tr); | |
3035 | return t->init(tr); | |
3036 | } | |
3037 | ||
438ced17 VN |
3038 | static void set_buffer_entries(struct trace_array *tr, unsigned long val) |
3039 | { | |
3040 | int cpu; | |
3041 | for_each_tracing_cpu(cpu) | |
3042 | tr->data[cpu]->entries = val; | |
3043 | } | |
3044 | ||
3045 | static int __tracing_resize_ring_buffer(unsigned long size, int cpu) | |
73c5162a SR |
3046 | { |
3047 | int ret; | |
3048 | ||
3049 | /* | |
3050 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
3051 | * we use the size that was given, and we can forget about |
3052 | * expanding it later. | |
73c5162a SR |
3053 | */ |
3054 | ring_buffer_expanded = 1; | |
3055 | ||
438ced17 | 3056 | ret = ring_buffer_resize(global_trace.buffer, size, cpu); |
73c5162a SR |
3057 | if (ret < 0) |
3058 | return ret; | |
3059 | ||
ef710e10 KM |
3060 | if (!current_trace->use_max_tr) |
3061 | goto out; | |
3062 | ||
438ced17 | 3063 | ret = ring_buffer_resize(max_tr.buffer, size, cpu); |
73c5162a | 3064 | if (ret < 0) { |
438ced17 VN |
3065 | int r = 0; |
3066 | ||
3067 | if (cpu == RING_BUFFER_ALL_CPUS) { | |
3068 | int i; | |
3069 | for_each_tracing_cpu(i) { | |
3070 | r = ring_buffer_resize(global_trace.buffer, | |
3071 | global_trace.data[i]->entries, | |
3072 | i); | |
3073 | if (r < 0) | |
3074 | break; | |
3075 | } | |
3076 | } else { | |
3077 | r = ring_buffer_resize(global_trace.buffer, | |
3078 | global_trace.data[cpu]->entries, | |
3079 | cpu); | |
3080 | } | |
73c5162a | 3081 | |
73c5162a | 3082 | if (r < 0) { |
a123c52b SR |
3083 | /* |
3084 | * AARGH! We are left with different | |
3085 | * size max buffer!!!! | |
3086 | * The max buffer is our "snapshot" buffer. | |
3087 | * When a tracer needs a snapshot (one of the | |
3088 | * latency tracers), it swaps the max buffer | |
3089 | * with the saved snap shot. We succeeded to | |
3090 | * update the size of the main buffer, but failed to | |
3091 | * update the size of the max buffer. But when we tried | |
3092 | * to reset the main buffer to the original size, we | |
3093 | * failed there too. This is very unlikely to | |
3094 | * happen, but if it does, warn and kill all | |
3095 | * tracing. | |
3096 | */ | |
73c5162a SR |
3097 | WARN_ON(1); |
3098 | tracing_disabled = 1; | |
3099 | } | |
3100 | return ret; | |
3101 | } | |
3102 | ||
438ced17 VN |
3103 | if (cpu == RING_BUFFER_ALL_CPUS) |
3104 | set_buffer_entries(&max_tr, size); | |
3105 | else | |
3106 | max_tr.data[cpu]->entries = size; | |
3107 | ||
ef710e10 | 3108 | out: |
438ced17 VN |
3109 | if (cpu == RING_BUFFER_ALL_CPUS) |
3110 | set_buffer_entries(&global_trace, size); | |
3111 | else | |
3112 | global_trace.data[cpu]->entries = size; | |
73c5162a SR |
3113 | |
3114 | return ret; | |
3115 | } | |
3116 | ||
438ced17 | 3117 | static ssize_t tracing_resize_ring_buffer(unsigned long size, int cpu_id) |
4f271a2a VN |
3118 | { |
3119 | int cpu, ret = size; | |
3120 | ||
3121 | mutex_lock(&trace_types_lock); | |
3122 | ||
3123 | tracing_stop(); | |
3124 | ||
3125 | /* disable all cpu buffers */ | |
3126 | for_each_tracing_cpu(cpu) { | |
3127 | if (global_trace.data[cpu]) | |
3128 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3129 | if (max_tr.data[cpu]) | |
3130 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3131 | } | |
3132 | ||
438ced17 VN |
3133 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
3134 | /* make sure, this cpu is enabled in the mask */ | |
3135 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
3136 | ret = -EINVAL; | |
3137 | goto out; | |
3138 | } | |
3139 | } | |
4f271a2a | 3140 | |
438ced17 | 3141 | ret = __tracing_resize_ring_buffer(size, cpu_id); |
4f271a2a VN |
3142 | if (ret < 0) |
3143 | ret = -ENOMEM; | |
3144 | ||
438ced17 | 3145 | out: |
4f271a2a VN |
3146 | for_each_tracing_cpu(cpu) { |
3147 | if (global_trace.data[cpu]) | |
3148 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3149 | if (max_tr.data[cpu]) | |
3150 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3151 | } | |
3152 | ||
3153 | tracing_start(); | |
3154 | mutex_unlock(&trace_types_lock); | |
3155 | ||
3156 | return ret; | |
3157 | } | |
3158 | ||
ef710e10 | 3159 | |
1852fcce SR |
3160 | /** |
3161 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
3162 | * | |
3163 | * To save on memory when the tracing is never used on a system with it | |
3164 | * configured in. The ring buffers are set to a minimum size. But once | |
3165 | * a user starts to use the tracing facility, then they need to grow | |
3166 | * to their default size. | |
3167 | * | |
3168 | * This function is to be called when a tracer is about to be used. | |
3169 | */ | |
3170 | int tracing_update_buffers(void) | |
3171 | { | |
3172 | int ret = 0; | |
3173 | ||
1027fcb2 | 3174 | mutex_lock(&trace_types_lock); |
1852fcce | 3175 | if (!ring_buffer_expanded) |
438ced17 VN |
3176 | ret = __tracing_resize_ring_buffer(trace_buf_size, |
3177 | RING_BUFFER_ALL_CPUS); | |
1027fcb2 | 3178 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
3179 | |
3180 | return ret; | |
3181 | } | |
3182 | ||
577b785f SR |
3183 | struct trace_option_dentry; |
3184 | ||
3185 | static struct trace_option_dentry * | |
3186 | create_trace_option_files(struct tracer *tracer); | |
3187 | ||
3188 | static void | |
3189 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
3190 | ||
b2821ae6 | 3191 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 3192 | { |
577b785f | 3193 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
3194 | struct trace_array *tr = &global_trace; |
3195 | struct tracer *t; | |
d9e54076 | 3196 | int ret = 0; |
bc0c38d1 | 3197 | |
1027fcb2 SR |
3198 | mutex_lock(&trace_types_lock); |
3199 | ||
73c5162a | 3200 | if (!ring_buffer_expanded) { |
438ced17 VN |
3201 | ret = __tracing_resize_ring_buffer(trace_buf_size, |
3202 | RING_BUFFER_ALL_CPUS); | |
73c5162a | 3203 | if (ret < 0) |
59f586db | 3204 | goto out; |
73c5162a SR |
3205 | ret = 0; |
3206 | } | |
3207 | ||
bc0c38d1 SR |
3208 | for (t = trace_types; t; t = t->next) { |
3209 | if (strcmp(t->name, buf) == 0) | |
3210 | break; | |
3211 | } | |
c2931e05 FW |
3212 | if (!t) { |
3213 | ret = -EINVAL; | |
3214 | goto out; | |
3215 | } | |
3216 | if (t == current_trace) | |
bc0c38d1 SR |
3217 | goto out; |
3218 | ||
9f029e83 | 3219 | trace_branch_disable(); |
bc0c38d1 SR |
3220 | if (current_trace && current_trace->reset) |
3221 | current_trace->reset(tr); | |
ef710e10 KM |
3222 | if (current_trace && current_trace->use_max_tr) { |
3223 | /* | |
3224 | * We don't free the ring buffer. instead, resize it because | |
3225 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
3226 | * we want preserve it. | |
3227 | */ | |
438ced17 VN |
3228 | ring_buffer_resize(max_tr.buffer, 1, RING_BUFFER_ALL_CPUS); |
3229 | set_buffer_entries(&max_tr, 1); | |
ef710e10 | 3230 | } |
577b785f SR |
3231 | destroy_trace_option_files(topts); |
3232 | ||
bc0c38d1 | 3233 | current_trace = t; |
577b785f SR |
3234 | |
3235 | topts = create_trace_option_files(current_trace); | |
ef710e10 | 3236 | if (current_trace->use_max_tr) { |
438ced17 VN |
3237 | int cpu; |
3238 | /* we need to make per cpu buffer sizes equivalent */ | |
3239 | for_each_tracing_cpu(cpu) { | |
3240 | ret = ring_buffer_resize(max_tr.buffer, | |
3241 | global_trace.data[cpu]->entries, | |
3242 | cpu); | |
3243 | if (ret < 0) | |
3244 | goto out; | |
3245 | max_tr.data[cpu]->entries = | |
3246 | global_trace.data[cpu]->entries; | |
3247 | } | |
ef710e10 | 3248 | } |
577b785f | 3249 | |
1c80025a | 3250 | if (t->init) { |
b6f11df2 | 3251 | ret = tracer_init(t, tr); |
1c80025a FW |
3252 | if (ret) |
3253 | goto out; | |
3254 | } | |
bc0c38d1 | 3255 | |
9f029e83 | 3256 | trace_branch_enable(tr); |
bc0c38d1 SR |
3257 | out: |
3258 | mutex_unlock(&trace_types_lock); | |
3259 | ||
d9e54076 PZ |
3260 | return ret; |
3261 | } | |
3262 | ||
3263 | static ssize_t | |
3264 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
3265 | size_t cnt, loff_t *ppos) | |
3266 | { | |
ee6c2c1b | 3267 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
3268 | int i; |
3269 | size_t ret; | |
e6e7a65a FW |
3270 | int err; |
3271 | ||
3272 | ret = cnt; | |
d9e54076 | 3273 | |
ee6c2c1b LZ |
3274 | if (cnt > MAX_TRACER_SIZE) |
3275 | cnt = MAX_TRACER_SIZE; | |
d9e54076 PZ |
3276 | |
3277 | if (copy_from_user(&buf, ubuf, cnt)) | |
3278 | return -EFAULT; | |
3279 | ||
3280 | buf[cnt] = 0; | |
3281 | ||
3282 | /* strip ending whitespace. */ | |
3283 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
3284 | buf[i] = 0; | |
3285 | ||
e6e7a65a FW |
3286 | err = tracing_set_tracer(buf); |
3287 | if (err) | |
3288 | return err; | |
d9e54076 | 3289 | |
cf8517cf | 3290 | *ppos += ret; |
bc0c38d1 | 3291 | |
c2931e05 | 3292 | return ret; |
bc0c38d1 SR |
3293 | } |
3294 | ||
3295 | static ssize_t | |
3296 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
3297 | size_t cnt, loff_t *ppos) | |
3298 | { | |
3299 | unsigned long *ptr = filp->private_data; | |
3300 | char buf[64]; | |
3301 | int r; | |
3302 | ||
cffae437 | 3303 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 3304 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
3305 | if (r > sizeof(buf)) |
3306 | r = sizeof(buf); | |
4bf39a94 | 3307 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
3308 | } |
3309 | ||
3310 | static ssize_t | |
3311 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
3312 | size_t cnt, loff_t *ppos) | |
3313 | { | |
5e39841c | 3314 | unsigned long *ptr = filp->private_data; |
5e39841c | 3315 | unsigned long val; |
c6caeeb1 | 3316 | int ret; |
bc0c38d1 | 3317 | |
22fe9b54 PH |
3318 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3319 | if (ret) | |
c6caeeb1 | 3320 | return ret; |
bc0c38d1 SR |
3321 | |
3322 | *ptr = val * 1000; | |
3323 | ||
3324 | return cnt; | |
3325 | } | |
3326 | ||
b3806b43 SR |
3327 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
3328 | { | |
b04cc6b1 | 3329 | long cpu_file = (long) inode->i_private; |
b3806b43 | 3330 | struct trace_iterator *iter; |
b04cc6b1 | 3331 | int ret = 0; |
b3806b43 SR |
3332 | |
3333 | if (tracing_disabled) | |
3334 | return -ENODEV; | |
3335 | ||
b04cc6b1 FW |
3336 | mutex_lock(&trace_types_lock); |
3337 | ||
b3806b43 SR |
3338 | /* create a buffer to store the information to pass to userspace */ |
3339 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
3340 | if (!iter) { |
3341 | ret = -ENOMEM; | |
3342 | goto out; | |
3343 | } | |
b3806b43 | 3344 | |
d7350c3f FW |
3345 | /* |
3346 | * We make a copy of the current tracer to avoid concurrent | |
3347 | * changes on it while we are reading. | |
3348 | */ | |
3349 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
3350 | if (!iter->trace) { | |
3351 | ret = -ENOMEM; | |
3352 | goto fail; | |
3353 | } | |
3354 | if (current_trace) | |
3355 | *iter->trace = *current_trace; | |
3356 | ||
4462344e | 3357 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 3358 | ret = -ENOMEM; |
d7350c3f | 3359 | goto fail; |
4462344e RR |
3360 | } |
3361 | ||
a309720c | 3362 | /* trace pipe does not show start of buffer */ |
4462344e | 3363 | cpumask_setall(iter->started); |
a309720c | 3364 | |
112f38a7 SR |
3365 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
3366 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
3367 | ||
b04cc6b1 | 3368 | iter->cpu_file = cpu_file; |
b3806b43 | 3369 | iter->tr = &global_trace; |
d7350c3f | 3370 | mutex_init(&iter->mutex); |
b3806b43 SR |
3371 | filp->private_data = iter; |
3372 | ||
107bad8b SR |
3373 | if (iter->trace->pipe_open) |
3374 | iter->trace->pipe_open(iter); | |
107bad8b | 3375 | |
b444786f | 3376 | nonseekable_open(inode, filp); |
b04cc6b1 FW |
3377 | out: |
3378 | mutex_unlock(&trace_types_lock); | |
3379 | return ret; | |
d7350c3f FW |
3380 | |
3381 | fail: | |
3382 | kfree(iter->trace); | |
3383 | kfree(iter); | |
3384 | mutex_unlock(&trace_types_lock); | |
3385 | return ret; | |
b3806b43 SR |
3386 | } |
3387 | ||
3388 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
3389 | { | |
3390 | struct trace_iterator *iter = file->private_data; | |
3391 | ||
b04cc6b1 FW |
3392 | mutex_lock(&trace_types_lock); |
3393 | ||
29bf4a5e | 3394 | if (iter->trace->pipe_close) |
c521efd1 SR |
3395 | iter->trace->pipe_close(iter); |
3396 | ||
b04cc6b1 FW |
3397 | mutex_unlock(&trace_types_lock); |
3398 | ||
4462344e | 3399 | free_cpumask_var(iter->started); |
d7350c3f FW |
3400 | mutex_destroy(&iter->mutex); |
3401 | kfree(iter->trace); | |
b3806b43 | 3402 | kfree(iter); |
b3806b43 SR |
3403 | |
3404 | return 0; | |
3405 | } | |
3406 | ||
2a2cc8f7 SSP |
3407 | static unsigned int |
3408 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
3409 | { | |
3410 | struct trace_iterator *iter = filp->private_data; | |
3411 | ||
3412 | if (trace_flags & TRACE_ITER_BLOCK) { | |
3413 | /* | |
3414 | * Always select as readable when in blocking mode | |
3415 | */ | |
3416 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 3417 | } else { |
2a2cc8f7 SSP |
3418 | if (!trace_empty(iter)) |
3419 | return POLLIN | POLLRDNORM; | |
3420 | poll_wait(filp, &trace_wait, poll_table); | |
3421 | if (!trace_empty(iter)) | |
3422 | return POLLIN | POLLRDNORM; | |
3423 | ||
3424 | return 0; | |
3425 | } | |
3426 | } | |
3427 | ||
6eaaa5d5 FW |
3428 | |
3429 | void default_wait_pipe(struct trace_iterator *iter) | |
3430 | { | |
3431 | DEFINE_WAIT(wait); | |
3432 | ||
3433 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
3434 | ||
3435 | if (trace_empty(iter)) | |
3436 | schedule(); | |
3437 | ||
3438 | finish_wait(&trace_wait, &wait); | |
3439 | } | |
3440 | ||
3441 | /* | |
3442 | * This is a make-shift waitqueue. | |
3443 | * A tracer might use this callback on some rare cases: | |
3444 | * | |
3445 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
3446 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
3447 | * 2) the function tracers, trace all functions, we don't want | |
3448 | * the overhead of calling wake_up and friends | |
3449 | * (and tracing them too) | |
3450 | * | |
3451 | * Anyway, this is really very primitive wakeup. | |
3452 | */ | |
3453 | void poll_wait_pipe(struct trace_iterator *iter) | |
3454 | { | |
3455 | set_current_state(TASK_INTERRUPTIBLE); | |
3456 | /* sleep for 100 msecs, and try again. */ | |
3457 | schedule_timeout(HZ / 10); | |
3458 | } | |
3459 | ||
ff98781b EGM |
3460 | /* Must be called with trace_types_lock mutex held. */ |
3461 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
3462 | { |
3463 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 3464 | |
b3806b43 | 3465 | while (trace_empty(iter)) { |
2dc8f095 | 3466 | |
107bad8b | 3467 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 3468 | return -EAGAIN; |
107bad8b | 3469 | } |
2dc8f095 | 3470 | |
d7350c3f | 3471 | mutex_unlock(&iter->mutex); |
107bad8b | 3472 | |
6eaaa5d5 | 3473 | iter->trace->wait_pipe(iter); |
b3806b43 | 3474 | |
d7350c3f | 3475 | mutex_lock(&iter->mutex); |
107bad8b | 3476 | |
6eaaa5d5 | 3477 | if (signal_pending(current)) |
ff98781b | 3478 | return -EINTR; |
b3806b43 SR |
3479 | |
3480 | /* | |
3481 | * We block until we read something and tracing is disabled. | |
3482 | * We still block if tracing is disabled, but we have never | |
3483 | * read anything. This allows a user to cat this file, and | |
3484 | * then enable tracing. But after we have read something, | |
3485 | * we give an EOF when tracing is again disabled. | |
3486 | * | |
3487 | * iter->pos will be 0 if we haven't read anything. | |
3488 | */ | |
3489 | if (!tracer_enabled && iter->pos) | |
3490 | break; | |
b3806b43 SR |
3491 | } |
3492 | ||
ff98781b EGM |
3493 | return 1; |
3494 | } | |
3495 | ||
3496 | /* | |
3497 | * Consumer reader. | |
3498 | */ | |
3499 | static ssize_t | |
3500 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
3501 | size_t cnt, loff_t *ppos) | |
3502 | { | |
3503 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 3504 | static struct tracer *old_tracer; |
ff98781b EGM |
3505 | ssize_t sret; |
3506 | ||
3507 | /* return any leftover data */ | |
3508 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
3509 | if (sret != -EBUSY) | |
3510 | return sret; | |
3511 | ||
f9520750 | 3512 | trace_seq_init(&iter->seq); |
ff98781b | 3513 | |
d7350c3f | 3514 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 3515 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3516 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3517 | old_tracer = current_trace; | |
3518 | *iter->trace = *current_trace; | |
3519 | } | |
3520 | mutex_unlock(&trace_types_lock); | |
3521 | ||
3522 | /* | |
3523 | * Avoid more than one consumer on a single file descriptor | |
3524 | * This is just a matter of traces coherency, the ring buffer itself | |
3525 | * is protected. | |
3526 | */ | |
3527 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
3528 | if (iter->trace->read) { |
3529 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
3530 | if (sret) | |
3531 | goto out; | |
3532 | } | |
3533 | ||
3534 | waitagain: | |
3535 | sret = tracing_wait_pipe(filp); | |
3536 | if (sret <= 0) | |
3537 | goto out; | |
3538 | ||
b3806b43 | 3539 | /* stop when tracing is finished */ |
ff98781b EGM |
3540 | if (trace_empty(iter)) { |
3541 | sret = 0; | |
107bad8b | 3542 | goto out; |
ff98781b | 3543 | } |
b3806b43 SR |
3544 | |
3545 | if (cnt >= PAGE_SIZE) | |
3546 | cnt = PAGE_SIZE - 1; | |
3547 | ||
53d0aa77 | 3548 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
3549 | memset(&iter->seq, 0, |
3550 | sizeof(struct trace_iterator) - | |
3551 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 3552 | iter->pos = -1; |
b3806b43 | 3553 | |
4f535968 | 3554 | trace_event_read_lock(); |
7e53bd42 | 3555 | trace_access_lock(iter->cpu_file); |
955b61e5 | 3556 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 3557 | enum print_line_t ret; |
088b1e42 SR |
3558 | int len = iter->seq.len; |
3559 | ||
f9896bf3 | 3560 | ret = print_trace_line(iter); |
2c4f035f | 3561 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
3562 | /* don't print partial lines */ |
3563 | iter->seq.len = len; | |
b3806b43 | 3564 | break; |
088b1e42 | 3565 | } |
b91facc3 FW |
3566 | if (ret != TRACE_TYPE_NO_CONSUME) |
3567 | trace_consume(iter); | |
b3806b43 SR |
3568 | |
3569 | if (iter->seq.len >= cnt) | |
3570 | break; | |
ee5e51f5 JO |
3571 | |
3572 | /* | |
3573 | * Setting the full flag means we reached the trace_seq buffer | |
3574 | * size and we should leave by partial output condition above. | |
3575 | * One of the trace_seq_* functions is not used properly. | |
3576 | */ | |
3577 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
3578 | iter->ent->type); | |
b3806b43 | 3579 | } |
7e53bd42 | 3580 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3581 | trace_event_read_unlock(); |
b3806b43 | 3582 | |
b3806b43 | 3583 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3584 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3585 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3586 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3587 | |
3588 | /* | |
25985edc | 3589 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
3590 | * entries, go back to wait for more entries. |
3591 | */ | |
6c6c2796 | 3592 | if (sret == -EBUSY) |
9ff4b974 | 3593 | goto waitagain; |
b3806b43 | 3594 | |
107bad8b | 3595 | out: |
d7350c3f | 3596 | mutex_unlock(&iter->mutex); |
107bad8b | 3597 | |
6c6c2796 | 3598 | return sret; |
b3806b43 SR |
3599 | } |
3600 | ||
3c56819b EGM |
3601 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3602 | struct pipe_buffer *buf) | |
3603 | { | |
3604 | __free_page(buf->page); | |
3605 | } | |
3606 | ||
3607 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3608 | unsigned int idx) | |
3609 | { | |
3610 | __free_page(spd->pages[idx]); | |
3611 | } | |
3612 | ||
28dfef8f | 3613 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 SR |
3614 | .can_merge = 0, |
3615 | .map = generic_pipe_buf_map, | |
3616 | .unmap = generic_pipe_buf_unmap, | |
3617 | .confirm = generic_pipe_buf_confirm, | |
3618 | .release = tracing_pipe_buf_release, | |
3619 | .steal = generic_pipe_buf_steal, | |
3620 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3621 | }; |
3622 | ||
34cd4998 | 3623 | static size_t |
fa7c7f6e | 3624 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3625 | { |
3626 | size_t count; | |
3627 | int ret; | |
3628 | ||
3629 | /* Seq buffer is page-sized, exactly what we need. */ | |
3630 | for (;;) { | |
3631 | count = iter->seq.len; | |
3632 | ret = print_trace_line(iter); | |
3633 | count = iter->seq.len - count; | |
3634 | if (rem < count) { | |
3635 | rem = 0; | |
3636 | iter->seq.len -= count; | |
3637 | break; | |
3638 | } | |
3639 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3640 | iter->seq.len -= count; | |
3641 | break; | |
3642 | } | |
3643 | ||
74e7ff8c LJ |
3644 | if (ret != TRACE_TYPE_NO_CONSUME) |
3645 | trace_consume(iter); | |
34cd4998 | 3646 | rem -= count; |
955b61e5 | 3647 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
3648 | rem = 0; |
3649 | iter->ent = NULL; | |
3650 | break; | |
3651 | } | |
3652 | } | |
3653 | ||
3654 | return rem; | |
3655 | } | |
3656 | ||
3c56819b EGM |
3657 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3658 | loff_t *ppos, | |
3659 | struct pipe_inode_info *pipe, | |
3660 | size_t len, | |
3661 | unsigned int flags) | |
3662 | { | |
35f3d14d JA |
3663 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
3664 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
3665 | struct trace_iterator *iter = filp->private_data; |
3666 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
3667 | .pages = pages_def, |
3668 | .partial = partial_def, | |
34cd4998 SR |
3669 | .nr_pages = 0, /* This gets updated below. */ |
3670 | .flags = flags, | |
3671 | .ops = &tracing_pipe_buf_ops, | |
3672 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3673 | }; |
d7350c3f | 3674 | static struct tracer *old_tracer; |
3c56819b | 3675 | ssize_t ret; |
34cd4998 | 3676 | size_t rem; |
3c56819b EGM |
3677 | unsigned int i; |
3678 | ||
35f3d14d JA |
3679 | if (splice_grow_spd(pipe, &spd)) |
3680 | return -ENOMEM; | |
3681 | ||
d7350c3f | 3682 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3683 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3684 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3685 | old_tracer = current_trace; | |
3686 | *iter->trace = *current_trace; | |
3687 | } | |
3688 | mutex_unlock(&trace_types_lock); | |
3689 | ||
3690 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3691 | |
3692 | if (iter->trace->splice_read) { | |
3693 | ret = iter->trace->splice_read(iter, filp, | |
3694 | ppos, pipe, len, flags); | |
3695 | if (ret) | |
34cd4998 | 3696 | goto out_err; |
3c56819b EGM |
3697 | } |
3698 | ||
3699 | ret = tracing_wait_pipe(filp); | |
3700 | if (ret <= 0) | |
34cd4998 | 3701 | goto out_err; |
3c56819b | 3702 | |
955b61e5 | 3703 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 3704 | ret = -EFAULT; |
34cd4998 | 3705 | goto out_err; |
3c56819b EGM |
3706 | } |
3707 | ||
4f535968 | 3708 | trace_event_read_lock(); |
7e53bd42 | 3709 | trace_access_lock(iter->cpu_file); |
4f535968 | 3710 | |
3c56819b | 3711 | /* Fill as many pages as possible. */ |
35f3d14d JA |
3712 | for (i = 0, rem = len; i < pipe->buffers && rem; i++) { |
3713 | spd.pages[i] = alloc_page(GFP_KERNEL); | |
3714 | if (!spd.pages[i]) | |
34cd4998 | 3715 | break; |
3c56819b | 3716 | |
fa7c7f6e | 3717 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3718 | |
3719 | /* Copy the data into the page, so we can start over. */ | |
3720 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 3721 | page_address(spd.pages[i]), |
3c56819b EGM |
3722 | iter->seq.len); |
3723 | if (ret < 0) { | |
35f3d14d | 3724 | __free_page(spd.pages[i]); |
3c56819b EGM |
3725 | break; |
3726 | } | |
35f3d14d JA |
3727 | spd.partial[i].offset = 0; |
3728 | spd.partial[i].len = iter->seq.len; | |
3c56819b | 3729 | |
f9520750 | 3730 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3731 | } |
3732 | ||
7e53bd42 | 3733 | trace_access_unlock(iter->cpu_file); |
4f535968 | 3734 | trace_event_read_unlock(); |
d7350c3f | 3735 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3736 | |
3737 | spd.nr_pages = i; | |
3738 | ||
35f3d14d JA |
3739 | ret = splice_to_pipe(pipe, &spd); |
3740 | out: | |
3741 | splice_shrink_spd(pipe, &spd); | |
3742 | return ret; | |
3c56819b | 3743 | |
34cd4998 | 3744 | out_err: |
d7350c3f | 3745 | mutex_unlock(&iter->mutex); |
35f3d14d | 3746 | goto out; |
3c56819b EGM |
3747 | } |
3748 | ||
438ced17 VN |
3749 | struct ftrace_entries_info { |
3750 | struct trace_array *tr; | |
3751 | int cpu; | |
3752 | }; | |
3753 | ||
3754 | static int tracing_entries_open(struct inode *inode, struct file *filp) | |
3755 | { | |
3756 | struct ftrace_entries_info *info; | |
3757 | ||
3758 | if (tracing_disabled) | |
3759 | return -ENODEV; | |
3760 | ||
3761 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3762 | if (!info) | |
3763 | return -ENOMEM; | |
3764 | ||
3765 | info->tr = &global_trace; | |
3766 | info->cpu = (unsigned long)inode->i_private; | |
3767 | ||
3768 | filp->private_data = info; | |
3769 | ||
3770 | return 0; | |
3771 | } | |
3772 | ||
a98a3c3f SR |
3773 | static ssize_t |
3774 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3775 | size_t cnt, loff_t *ppos) | |
3776 | { | |
438ced17 VN |
3777 | struct ftrace_entries_info *info = filp->private_data; |
3778 | struct trace_array *tr = info->tr; | |
3779 | char buf[64]; | |
3780 | int r = 0; | |
3781 | ssize_t ret; | |
a98a3c3f | 3782 | |
db526ca3 | 3783 | mutex_lock(&trace_types_lock); |
438ced17 VN |
3784 | |
3785 | if (info->cpu == RING_BUFFER_ALL_CPUS) { | |
3786 | int cpu, buf_size_same; | |
3787 | unsigned long size; | |
3788 | ||
3789 | size = 0; | |
3790 | buf_size_same = 1; | |
3791 | /* check if all cpu sizes are same */ | |
3792 | for_each_tracing_cpu(cpu) { | |
3793 | /* fill in the size from first enabled cpu */ | |
3794 | if (size == 0) | |
3795 | size = tr->data[cpu]->entries; | |
3796 | if (size != tr->data[cpu]->entries) { | |
3797 | buf_size_same = 0; | |
3798 | break; | |
3799 | } | |
3800 | } | |
3801 | ||
3802 | if (buf_size_same) { | |
3803 | if (!ring_buffer_expanded) | |
3804 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3805 | size >> 10, | |
3806 | trace_buf_size >> 10); | |
3807 | else | |
3808 | r = sprintf(buf, "%lu\n", size >> 10); | |
3809 | } else | |
3810 | r = sprintf(buf, "X\n"); | |
3811 | } else | |
3812 | r = sprintf(buf, "%lu\n", tr->data[info->cpu]->entries >> 10); | |
3813 | ||
db526ca3 SR |
3814 | mutex_unlock(&trace_types_lock); |
3815 | ||
438ced17 VN |
3816 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3817 | return ret; | |
a98a3c3f SR |
3818 | } |
3819 | ||
3820 | static ssize_t | |
3821 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3822 | size_t cnt, loff_t *ppos) | |
3823 | { | |
438ced17 | 3824 | struct ftrace_entries_info *info = filp->private_data; |
a98a3c3f | 3825 | unsigned long val; |
4f271a2a | 3826 | int ret; |
a98a3c3f | 3827 | |
22fe9b54 PH |
3828 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
3829 | if (ret) | |
c6caeeb1 | 3830 | return ret; |
a98a3c3f SR |
3831 | |
3832 | /* must have at least 1 entry */ | |
3833 | if (!val) | |
3834 | return -EINVAL; | |
3835 | ||
1696b2b0 SR |
3836 | /* value is in KB */ |
3837 | val <<= 10; | |
3838 | ||
438ced17 | 3839 | ret = tracing_resize_ring_buffer(val, info->cpu); |
4f271a2a VN |
3840 | if (ret < 0) |
3841 | return ret; | |
a98a3c3f | 3842 | |
cf8517cf | 3843 | *ppos += cnt; |
a98a3c3f | 3844 | |
4f271a2a VN |
3845 | return cnt; |
3846 | } | |
bf5e6519 | 3847 | |
438ced17 VN |
3848 | static int |
3849 | tracing_entries_release(struct inode *inode, struct file *filp) | |
3850 | { | |
3851 | struct ftrace_entries_info *info = filp->private_data; | |
3852 | ||
3853 | kfree(info); | |
3854 | ||
3855 | return 0; | |
3856 | } | |
3857 | ||
f81ab074 VN |
3858 | static ssize_t |
3859 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
3860 | size_t cnt, loff_t *ppos) | |
3861 | { | |
3862 | struct trace_array *tr = filp->private_data; | |
3863 | char buf[64]; | |
3864 | int r, cpu; | |
3865 | unsigned long size = 0, expanded_size = 0; | |
3866 | ||
3867 | mutex_lock(&trace_types_lock); | |
3868 | for_each_tracing_cpu(cpu) { | |
438ced17 | 3869 | size += tr->data[cpu]->entries >> 10; |
f81ab074 VN |
3870 | if (!ring_buffer_expanded) |
3871 | expanded_size += trace_buf_size >> 10; | |
3872 | } | |
3873 | if (ring_buffer_expanded) | |
3874 | r = sprintf(buf, "%lu\n", size); | |
3875 | else | |
3876 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
3877 | mutex_unlock(&trace_types_lock); | |
3878 | ||
3879 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3880 | } | |
3881 | ||
4f271a2a VN |
3882 | static ssize_t |
3883 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
3884 | size_t cnt, loff_t *ppos) | |
3885 | { | |
3886 | /* | |
3887 | * There is no need to read what the user has written, this function | |
3888 | * is just to make sure that there is no error when "echo" is used | |
3889 | */ | |
3890 | ||
3891 | *ppos += cnt; | |
a98a3c3f SR |
3892 | |
3893 | return cnt; | |
3894 | } | |
3895 | ||
4f271a2a VN |
3896 | static int |
3897 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
3898 | { | |
cf30cf67 SR |
3899 | /* disable tracing ? */ |
3900 | if (trace_flags & TRACE_ITER_STOP_ON_FREE) | |
3901 | tracing_off(); | |
4f271a2a | 3902 | /* resize the ring buffer to 0 */ |
438ced17 | 3903 | tracing_resize_ring_buffer(0, RING_BUFFER_ALL_CPUS); |
4f271a2a VN |
3904 | |
3905 | return 0; | |
3906 | } | |
3907 | ||
5bf9a1ee PP |
3908 | static ssize_t |
3909 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3910 | size_t cnt, loff_t *fpos) | |
3911 | { | |
d696b58c SR |
3912 | unsigned long addr = (unsigned long)ubuf; |
3913 | struct ring_buffer_event *event; | |
3914 | struct ring_buffer *buffer; | |
3915 | struct print_entry *entry; | |
3916 | unsigned long irq_flags; | |
3917 | struct page *pages[2]; | |
3918 | int nr_pages = 1; | |
3919 | ssize_t written; | |
3920 | void *page1; | |
3921 | void *page2; | |
3922 | int offset; | |
3923 | int size; | |
3924 | int len; | |
3925 | int ret; | |
5bf9a1ee | 3926 | |
c76f0694 | 3927 | if (tracing_disabled) |
5bf9a1ee PP |
3928 | return -EINVAL; |
3929 | ||
3930 | if (cnt > TRACE_BUF_SIZE) | |
3931 | cnt = TRACE_BUF_SIZE; | |
3932 | ||
d696b58c SR |
3933 | /* |
3934 | * Userspace is injecting traces into the kernel trace buffer. | |
3935 | * We want to be as non intrusive as possible. | |
3936 | * To do so, we do not want to allocate any special buffers | |
3937 | * or take any locks, but instead write the userspace data | |
3938 | * straight into the ring buffer. | |
3939 | * | |
3940 | * First we need to pin the userspace buffer into memory, | |
3941 | * which, most likely it is, because it just referenced it. | |
3942 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
3943 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
3944 | * pages directly. We then write the data directly into the | |
3945 | * ring buffer. | |
3946 | */ | |
3947 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 3948 | |
d696b58c SR |
3949 | /* check if we cross pages */ |
3950 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
3951 | nr_pages = 2; | |
3952 | ||
3953 | offset = addr & (PAGE_SIZE - 1); | |
3954 | addr &= PAGE_MASK; | |
3955 | ||
3956 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
3957 | if (ret < nr_pages) { | |
3958 | while (--ret >= 0) | |
3959 | put_page(pages[ret]); | |
3960 | written = -EFAULT; | |
3961 | goto out; | |
5bf9a1ee | 3962 | } |
d696b58c SR |
3963 | |
3964 | page1 = kmap_atomic(pages[0]); | |
3965 | if (nr_pages == 2) | |
3966 | page2 = kmap_atomic(pages[1]); | |
3967 | ||
3968 | local_save_flags(irq_flags); | |
3969 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
3970 | buffer = global_trace.buffer; | |
3971 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, | |
3972 | irq_flags, preempt_count()); | |
3973 | if (!event) { | |
3974 | /* Ring buffer disabled, return as if not open for write */ | |
3975 | written = -EBADF; | |
3976 | goto out_unlock; | |
5bf9a1ee | 3977 | } |
d696b58c SR |
3978 | |
3979 | entry = ring_buffer_event_data(event); | |
3980 | entry->ip = _THIS_IP_; | |
3981 | ||
3982 | if (nr_pages == 2) { | |
3983 | len = PAGE_SIZE - offset; | |
3984 | memcpy(&entry->buf, page1 + offset, len); | |
3985 | memcpy(&entry->buf[len], page2, cnt - len); | |
c13d2f7c | 3986 | } else |
d696b58c | 3987 | memcpy(&entry->buf, page1 + offset, cnt); |
5bf9a1ee | 3988 | |
d696b58c SR |
3989 | if (entry->buf[cnt - 1] != '\n') { |
3990 | entry->buf[cnt] = '\n'; | |
3991 | entry->buf[cnt + 1] = '\0'; | |
3992 | } else | |
3993 | entry->buf[cnt] = '\0'; | |
3994 | ||
3995 | ring_buffer_unlock_commit(buffer, event); | |
5bf9a1ee | 3996 | |
d696b58c | 3997 | written = cnt; |
5bf9a1ee | 3998 | |
d696b58c | 3999 | *fpos += written; |
1aa54bca | 4000 | |
d696b58c SR |
4001 | out_unlock: |
4002 | if (nr_pages == 2) | |
4003 | kunmap_atomic(page2); | |
4004 | kunmap_atomic(page1); | |
4005 | while (nr_pages > 0) | |
4006 | put_page(pages[--nr_pages]); | |
4007 | out: | |
1aa54bca | 4008 | return written; |
5bf9a1ee PP |
4009 | } |
4010 | ||
13f16d20 | 4011 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 4012 | { |
5079f326 Z |
4013 | int i; |
4014 | ||
4015 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 4016 | seq_printf(m, |
5079f326 Z |
4017 | "%s%s%s%s", i ? " " : "", |
4018 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
4019 | i == trace_clock_id ? "]" : ""); | |
13f16d20 | 4020 | seq_putc(m, '\n'); |
5079f326 | 4021 | |
13f16d20 | 4022 | return 0; |
5079f326 Z |
4023 | } |
4024 | ||
4025 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
4026 | size_t cnt, loff_t *fpos) | |
4027 | { | |
4028 | char buf[64]; | |
4029 | const char *clockstr; | |
4030 | int i; | |
4031 | ||
4032 | if (cnt >= sizeof(buf)) | |
4033 | return -EINVAL; | |
4034 | ||
4035 | if (copy_from_user(&buf, ubuf, cnt)) | |
4036 | return -EFAULT; | |
4037 | ||
4038 | buf[cnt] = 0; | |
4039 | ||
4040 | clockstr = strstrip(buf); | |
4041 | ||
4042 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
4043 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
4044 | break; | |
4045 | } | |
4046 | if (i == ARRAY_SIZE(trace_clocks)) | |
4047 | return -EINVAL; | |
4048 | ||
4049 | trace_clock_id = i; | |
4050 | ||
4051 | mutex_lock(&trace_types_lock); | |
4052 | ||
4053 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
4054 | if (max_tr.buffer) | |
4055 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
4056 | ||
4057 | mutex_unlock(&trace_types_lock); | |
4058 | ||
4059 | *fpos += cnt; | |
4060 | ||
4061 | return cnt; | |
4062 | } | |
4063 | ||
13f16d20 LZ |
4064 | static int tracing_clock_open(struct inode *inode, struct file *file) |
4065 | { | |
4066 | if (tracing_disabled) | |
4067 | return -ENODEV; | |
4068 | return single_open(file, tracing_clock_show, NULL); | |
4069 | } | |
4070 | ||
5e2336a0 | 4071 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
4072 | .open = tracing_open_generic, |
4073 | .read = tracing_max_lat_read, | |
4074 | .write = tracing_max_lat_write, | |
b444786f | 4075 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4076 | }; |
4077 | ||
5e2336a0 | 4078 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
4079 | .open = tracing_open_generic, |
4080 | .read = tracing_ctrl_read, | |
4081 | .write = tracing_ctrl_write, | |
b444786f | 4082 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4083 | }; |
4084 | ||
5e2336a0 | 4085 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
4086 | .open = tracing_open_generic, |
4087 | .read = tracing_set_trace_read, | |
4088 | .write = tracing_set_trace_write, | |
b444786f | 4089 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4090 | }; |
4091 | ||
5e2336a0 | 4092 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 4093 | .open = tracing_open_pipe, |
2a2cc8f7 | 4094 | .poll = tracing_poll_pipe, |
4bf39a94 | 4095 | .read = tracing_read_pipe, |
3c56819b | 4096 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 4097 | .release = tracing_release_pipe, |
b444786f | 4098 | .llseek = no_llseek, |
b3806b43 SR |
4099 | }; |
4100 | ||
5e2336a0 | 4101 | static const struct file_operations tracing_entries_fops = { |
438ced17 | 4102 | .open = tracing_entries_open, |
a98a3c3f SR |
4103 | .read = tracing_entries_read, |
4104 | .write = tracing_entries_write, | |
438ced17 | 4105 | .release = tracing_entries_release, |
b444786f | 4106 | .llseek = generic_file_llseek, |
a98a3c3f SR |
4107 | }; |
4108 | ||
f81ab074 VN |
4109 | static const struct file_operations tracing_total_entries_fops = { |
4110 | .open = tracing_open_generic, | |
4111 | .read = tracing_total_entries_read, | |
4112 | .llseek = generic_file_llseek, | |
4113 | }; | |
4114 | ||
4f271a2a VN |
4115 | static const struct file_operations tracing_free_buffer_fops = { |
4116 | .write = tracing_free_buffer_write, | |
4117 | .release = tracing_free_buffer_release, | |
4118 | }; | |
4119 | ||
5e2336a0 | 4120 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 4121 | .open = tracing_open_generic, |
5bf9a1ee | 4122 | .write = tracing_mark_write, |
b444786f | 4123 | .llseek = generic_file_llseek, |
5bf9a1ee PP |
4124 | }; |
4125 | ||
5079f326 | 4126 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
4127 | .open = tracing_clock_open, |
4128 | .read = seq_read, | |
4129 | .llseek = seq_lseek, | |
4130 | .release = single_release, | |
5079f326 Z |
4131 | .write = tracing_clock_write, |
4132 | }; | |
4133 | ||
2cadf913 SR |
4134 | struct ftrace_buffer_info { |
4135 | struct trace_array *tr; | |
4136 | void *spare; | |
4137 | int cpu; | |
4138 | unsigned int read; | |
4139 | }; | |
4140 | ||
4141 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
4142 | { | |
4143 | int cpu = (int)(long)inode->i_private; | |
4144 | struct ftrace_buffer_info *info; | |
4145 | ||
4146 | if (tracing_disabled) | |
4147 | return -ENODEV; | |
4148 | ||
4149 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
4150 | if (!info) | |
4151 | return -ENOMEM; | |
4152 | ||
4153 | info->tr = &global_trace; | |
4154 | info->cpu = cpu; | |
ddd538f3 | 4155 | info->spare = NULL; |
2cadf913 SR |
4156 | /* Force reading ring buffer for first read */ |
4157 | info->read = (unsigned int)-1; | |
2cadf913 SR |
4158 | |
4159 | filp->private_data = info; | |
4160 | ||
d1e7e02f | 4161 | return nonseekable_open(inode, filp); |
2cadf913 SR |
4162 | } |
4163 | ||
4164 | static ssize_t | |
4165 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
4166 | size_t count, loff_t *ppos) | |
4167 | { | |
4168 | struct ftrace_buffer_info *info = filp->private_data; | |
2cadf913 SR |
4169 | ssize_t ret; |
4170 | size_t size; | |
4171 | ||
2dc5d12b SR |
4172 | if (!count) |
4173 | return 0; | |
4174 | ||
ddd538f3 | 4175 | if (!info->spare) |
7ea59064 | 4176 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer, info->cpu); |
ddd538f3 LJ |
4177 | if (!info->spare) |
4178 | return -ENOMEM; | |
4179 | ||
2cadf913 SR |
4180 | /* Do we have previous read data to read? */ |
4181 | if (info->read < PAGE_SIZE) | |
4182 | goto read; | |
4183 | ||
7e53bd42 | 4184 | trace_access_lock(info->cpu); |
2cadf913 SR |
4185 | ret = ring_buffer_read_page(info->tr->buffer, |
4186 | &info->spare, | |
4187 | count, | |
4188 | info->cpu, 0); | |
7e53bd42 | 4189 | trace_access_unlock(info->cpu); |
2cadf913 SR |
4190 | if (ret < 0) |
4191 | return 0; | |
4192 | ||
436fc280 SR |
4193 | info->read = 0; |
4194 | ||
2cadf913 SR |
4195 | read: |
4196 | size = PAGE_SIZE - info->read; | |
4197 | if (size > count) | |
4198 | size = count; | |
4199 | ||
4200 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 4201 | if (ret == size) |
2cadf913 | 4202 | return -EFAULT; |
2dc5d12b SR |
4203 | size -= ret; |
4204 | ||
2cadf913 SR |
4205 | *ppos += size; |
4206 | info->read += size; | |
4207 | ||
4208 | return size; | |
4209 | } | |
4210 | ||
4211 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
4212 | { | |
4213 | struct ftrace_buffer_info *info = file->private_data; | |
4214 | ||
ddd538f3 LJ |
4215 | if (info->spare) |
4216 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
4217 | kfree(info); |
4218 | ||
4219 | return 0; | |
4220 | } | |
4221 | ||
4222 | struct buffer_ref { | |
4223 | struct ring_buffer *buffer; | |
4224 | void *page; | |
4225 | int ref; | |
4226 | }; | |
4227 | ||
4228 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
4229 | struct pipe_buffer *buf) | |
4230 | { | |
4231 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
4232 | ||
4233 | if (--ref->ref) | |
4234 | return; | |
4235 | ||
4236 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
4237 | kfree(ref); | |
4238 | buf->private = 0; | |
4239 | } | |
4240 | ||
4241 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
4242 | struct pipe_buffer *buf) | |
4243 | { | |
4244 | return 1; | |
4245 | } | |
4246 | ||
4247 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
4248 | struct pipe_buffer *buf) | |
4249 | { | |
4250 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
4251 | ||
4252 | ref->ref++; | |
4253 | } | |
4254 | ||
4255 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 4256 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 SR |
4257 | .can_merge = 0, |
4258 | .map = generic_pipe_buf_map, | |
4259 | .unmap = generic_pipe_buf_unmap, | |
4260 | .confirm = generic_pipe_buf_confirm, | |
4261 | .release = buffer_pipe_buf_release, | |
4262 | .steal = buffer_pipe_buf_steal, | |
4263 | .get = buffer_pipe_buf_get, | |
4264 | }; | |
4265 | ||
4266 | /* | |
4267 | * Callback from splice_to_pipe(), if we need to release some pages | |
4268 | * at the end of the spd in case we error'ed out in filling the pipe. | |
4269 | */ | |
4270 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
4271 | { | |
4272 | struct buffer_ref *ref = | |
4273 | (struct buffer_ref *)spd->partial[i].private; | |
4274 | ||
4275 | if (--ref->ref) | |
4276 | return; | |
4277 | ||
4278 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
4279 | kfree(ref); | |
4280 | spd->partial[i].private = 0; | |
4281 | } | |
4282 | ||
4283 | static ssize_t | |
4284 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
4285 | struct pipe_inode_info *pipe, size_t len, | |
4286 | unsigned int flags) | |
4287 | { | |
4288 | struct ftrace_buffer_info *info = file->private_data; | |
35f3d14d JA |
4289 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
4290 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 4291 | struct splice_pipe_desc spd = { |
35f3d14d JA |
4292 | .pages = pages_def, |
4293 | .partial = partial_def, | |
2cadf913 SR |
4294 | .flags = flags, |
4295 | .ops = &buffer_pipe_buf_ops, | |
4296 | .spd_release = buffer_spd_release, | |
4297 | }; | |
4298 | struct buffer_ref *ref; | |
93459c6c | 4299 | int entries, size, i; |
2cadf913 SR |
4300 | size_t ret; |
4301 | ||
35f3d14d JA |
4302 | if (splice_grow_spd(pipe, &spd)) |
4303 | return -ENOMEM; | |
4304 | ||
93cfb3c9 LJ |
4305 | if (*ppos & (PAGE_SIZE - 1)) { |
4306 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
35f3d14d JA |
4307 | ret = -EINVAL; |
4308 | goto out; | |
93cfb3c9 LJ |
4309 | } |
4310 | ||
4311 | if (len & (PAGE_SIZE - 1)) { | |
4312 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
35f3d14d JA |
4313 | if (len < PAGE_SIZE) { |
4314 | ret = -EINVAL; | |
4315 | goto out; | |
4316 | } | |
93cfb3c9 LJ |
4317 | len &= PAGE_MASK; |
4318 | } | |
4319 | ||
7e53bd42 | 4320 | trace_access_lock(info->cpu); |
93459c6c SR |
4321 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
4322 | ||
35f3d14d | 4323 | for (i = 0; i < pipe->buffers && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
4324 | struct page *page; |
4325 | int r; | |
4326 | ||
4327 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
4328 | if (!ref) | |
4329 | break; | |
4330 | ||
7267fa68 | 4331 | ref->ref = 1; |
2cadf913 | 4332 | ref->buffer = info->tr->buffer; |
7ea59064 | 4333 | ref->page = ring_buffer_alloc_read_page(ref->buffer, info->cpu); |
2cadf913 SR |
4334 | if (!ref->page) { |
4335 | kfree(ref); | |
4336 | break; | |
4337 | } | |
4338 | ||
4339 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 4340 | len, info->cpu, 1); |
2cadf913 | 4341 | if (r < 0) { |
7ea59064 | 4342 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
4343 | kfree(ref); |
4344 | break; | |
4345 | } | |
4346 | ||
4347 | /* | |
4348 | * zero out any left over data, this is going to | |
4349 | * user land. | |
4350 | */ | |
4351 | size = ring_buffer_page_len(ref->page); | |
4352 | if (size < PAGE_SIZE) | |
4353 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
4354 | ||
4355 | page = virt_to_page(ref->page); | |
4356 | ||
4357 | spd.pages[i] = page; | |
4358 | spd.partial[i].len = PAGE_SIZE; | |
4359 | spd.partial[i].offset = 0; | |
4360 | spd.partial[i].private = (unsigned long)ref; | |
4361 | spd.nr_pages++; | |
93cfb3c9 | 4362 | *ppos += PAGE_SIZE; |
93459c6c SR |
4363 | |
4364 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
4365 | } |
4366 | ||
7e53bd42 | 4367 | trace_access_unlock(info->cpu); |
2cadf913 SR |
4368 | spd.nr_pages = i; |
4369 | ||
4370 | /* did we read anything? */ | |
4371 | if (!spd.nr_pages) { | |
4372 | if (flags & SPLICE_F_NONBLOCK) | |
4373 | ret = -EAGAIN; | |
4374 | else | |
4375 | ret = 0; | |
4376 | /* TODO: block */ | |
35f3d14d | 4377 | goto out; |
2cadf913 SR |
4378 | } |
4379 | ||
4380 | ret = splice_to_pipe(pipe, &spd); | |
35f3d14d JA |
4381 | splice_shrink_spd(pipe, &spd); |
4382 | out: | |
2cadf913 SR |
4383 | return ret; |
4384 | } | |
4385 | ||
4386 | static const struct file_operations tracing_buffers_fops = { | |
4387 | .open = tracing_buffers_open, | |
4388 | .read = tracing_buffers_read, | |
4389 | .release = tracing_buffers_release, | |
4390 | .splice_read = tracing_buffers_splice_read, | |
4391 | .llseek = no_llseek, | |
4392 | }; | |
4393 | ||
c8d77183 SR |
4394 | static ssize_t |
4395 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
4396 | size_t count, loff_t *ppos) | |
4397 | { | |
4398 | unsigned long cpu = (unsigned long)filp->private_data; | |
4399 | struct trace_array *tr = &global_trace; | |
4400 | struct trace_seq *s; | |
4401 | unsigned long cnt; | |
c64e148a VN |
4402 | unsigned long long t; |
4403 | unsigned long usec_rem; | |
c8d77183 | 4404 | |
e4f2d10f | 4405 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 4406 | if (!s) |
a646365c | 4407 | return -ENOMEM; |
c8d77183 SR |
4408 | |
4409 | trace_seq_init(s); | |
4410 | ||
4411 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
4412 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
4413 | ||
4414 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
4415 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
4416 | ||
4417 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
4418 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
4419 | ||
c64e148a VN |
4420 | cnt = ring_buffer_bytes_cpu(tr->buffer, cpu); |
4421 | trace_seq_printf(s, "bytes: %ld\n", cnt); | |
4422 | ||
4423 | t = ns2usecs(ring_buffer_oldest_event_ts(tr->buffer, cpu)); | |
4424 | usec_rem = do_div(t, USEC_PER_SEC); | |
4425 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", t, usec_rem); | |
4426 | ||
4427 | t = ns2usecs(ring_buffer_time_stamp(tr->buffer, cpu)); | |
4428 | usec_rem = do_div(t, USEC_PER_SEC); | |
4429 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
4430 | ||
c8d77183 SR |
4431 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
4432 | ||
4433 | kfree(s); | |
4434 | ||
4435 | return count; | |
4436 | } | |
4437 | ||
4438 | static const struct file_operations tracing_stats_fops = { | |
4439 | .open = tracing_open_generic, | |
4440 | .read = tracing_stats_read, | |
b444786f | 4441 | .llseek = generic_file_llseek, |
c8d77183 SR |
4442 | }; |
4443 | ||
bc0c38d1 SR |
4444 | #ifdef CONFIG_DYNAMIC_FTRACE |
4445 | ||
b807c3d0 SR |
4446 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
4447 | { | |
4448 | return 0; | |
4449 | } | |
4450 | ||
bc0c38d1 | 4451 | static ssize_t |
b807c3d0 | 4452 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
4453 | size_t cnt, loff_t *ppos) |
4454 | { | |
a26a2a27 SR |
4455 | static char ftrace_dyn_info_buffer[1024]; |
4456 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 4457 | unsigned long *p = filp->private_data; |
b807c3d0 | 4458 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 4459 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
4460 | int r; |
4461 | ||
b807c3d0 SR |
4462 | mutex_lock(&dyn_info_mutex); |
4463 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 4464 | |
a26a2a27 | 4465 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
4466 | buf[r++] = '\n'; |
4467 | ||
4468 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4469 | ||
4470 | mutex_unlock(&dyn_info_mutex); | |
4471 | ||
4472 | return r; | |
bc0c38d1 SR |
4473 | } |
4474 | ||
5e2336a0 | 4475 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 4476 | .open = tracing_open_generic, |
b807c3d0 | 4477 | .read = tracing_read_dyn_info, |
b444786f | 4478 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
4479 | }; |
4480 | #endif | |
4481 | ||
4482 | static struct dentry *d_tracer; | |
4483 | ||
4484 | struct dentry *tracing_init_dentry(void) | |
4485 | { | |
4486 | static int once; | |
4487 | ||
4488 | if (d_tracer) | |
4489 | return d_tracer; | |
4490 | ||
3e1f60b8 FW |
4491 | if (!debugfs_initialized()) |
4492 | return NULL; | |
4493 | ||
bc0c38d1 SR |
4494 | d_tracer = debugfs_create_dir("tracing", NULL); |
4495 | ||
4496 | if (!d_tracer && !once) { | |
4497 | once = 1; | |
4498 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
4499 | return NULL; | |
4500 | } | |
4501 | ||
4502 | return d_tracer; | |
4503 | } | |
4504 | ||
b04cc6b1 FW |
4505 | static struct dentry *d_percpu; |
4506 | ||
4507 | struct dentry *tracing_dentry_percpu(void) | |
4508 | { | |
4509 | static int once; | |
4510 | struct dentry *d_tracer; | |
4511 | ||
4512 | if (d_percpu) | |
4513 | return d_percpu; | |
4514 | ||
4515 | d_tracer = tracing_init_dentry(); | |
4516 | ||
4517 | if (!d_tracer) | |
4518 | return NULL; | |
4519 | ||
4520 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
4521 | ||
4522 | if (!d_percpu && !once) { | |
4523 | once = 1; | |
4524 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
4525 | return NULL; | |
4526 | } | |
4527 | ||
4528 | return d_percpu; | |
4529 | } | |
4530 | ||
4531 | static void tracing_init_debugfs_percpu(long cpu) | |
4532 | { | |
4533 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 4534 | struct dentry *d_cpu; |
dd49a38c | 4535 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 4536 | |
dd49a38c | 4537 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8656e7a2 FW |
4538 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); |
4539 | if (!d_cpu) { | |
4540 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
4541 | return; | |
4542 | } | |
b04cc6b1 | 4543 | |
8656e7a2 | 4544 | /* per cpu trace_pipe */ |
5452af66 FW |
4545 | trace_create_file("trace_pipe", 0444, d_cpu, |
4546 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
4547 | |
4548 | /* per cpu trace */ | |
5452af66 FW |
4549 | trace_create_file("trace", 0644, d_cpu, |
4550 | (void *) cpu, &tracing_fops); | |
7f96f93f | 4551 | |
5452af66 FW |
4552 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
4553 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 4554 | |
c8d77183 SR |
4555 | trace_create_file("stats", 0444, d_cpu, |
4556 | (void *) cpu, &tracing_stats_fops); | |
438ced17 VN |
4557 | |
4558 | trace_create_file("buffer_size_kb", 0444, d_cpu, | |
4559 | (void *) cpu, &tracing_entries_fops); | |
b04cc6b1 FW |
4560 | } |
4561 | ||
60a11774 SR |
4562 | #ifdef CONFIG_FTRACE_SELFTEST |
4563 | /* Let selftest have access to static functions in this file */ | |
4564 | #include "trace_selftest.c" | |
4565 | #endif | |
4566 | ||
577b785f SR |
4567 | struct trace_option_dentry { |
4568 | struct tracer_opt *opt; | |
4569 | struct tracer_flags *flags; | |
4570 | struct dentry *entry; | |
4571 | }; | |
4572 | ||
4573 | static ssize_t | |
4574 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4575 | loff_t *ppos) | |
4576 | { | |
4577 | struct trace_option_dentry *topt = filp->private_data; | |
4578 | char *buf; | |
4579 | ||
4580 | if (topt->flags->val & topt->opt->bit) | |
4581 | buf = "1\n"; | |
4582 | else | |
4583 | buf = "0\n"; | |
4584 | ||
4585 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4586 | } | |
4587 | ||
4588 | static ssize_t | |
4589 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4590 | loff_t *ppos) | |
4591 | { | |
4592 | struct trace_option_dentry *topt = filp->private_data; | |
4593 | unsigned long val; | |
577b785f SR |
4594 | int ret; |
4595 | ||
22fe9b54 PH |
4596 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4597 | if (ret) | |
577b785f SR |
4598 | return ret; |
4599 | ||
8d18eaaf LZ |
4600 | if (val != 0 && val != 1) |
4601 | return -EINVAL; | |
577b785f | 4602 | |
8d18eaaf | 4603 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 4604 | mutex_lock(&trace_types_lock); |
8d18eaaf | 4605 | ret = __set_tracer_option(current_trace, topt->flags, |
c757bea9 | 4606 | topt->opt, !val); |
577b785f SR |
4607 | mutex_unlock(&trace_types_lock); |
4608 | if (ret) | |
4609 | return ret; | |
577b785f SR |
4610 | } |
4611 | ||
4612 | *ppos += cnt; | |
4613 | ||
4614 | return cnt; | |
4615 | } | |
4616 | ||
4617 | ||
4618 | static const struct file_operations trace_options_fops = { | |
4619 | .open = tracing_open_generic, | |
4620 | .read = trace_options_read, | |
4621 | .write = trace_options_write, | |
b444786f | 4622 | .llseek = generic_file_llseek, |
577b785f SR |
4623 | }; |
4624 | ||
a8259075 SR |
4625 | static ssize_t |
4626 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
4627 | loff_t *ppos) | |
4628 | { | |
4629 | long index = (long)filp->private_data; | |
4630 | char *buf; | |
4631 | ||
4632 | if (trace_flags & (1 << index)) | |
4633 | buf = "1\n"; | |
4634 | else | |
4635 | buf = "0\n"; | |
4636 | ||
4637 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
4638 | } | |
4639 | ||
4640 | static ssize_t | |
4641 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
4642 | loff_t *ppos) | |
4643 | { | |
4644 | long index = (long)filp->private_data; | |
a8259075 SR |
4645 | unsigned long val; |
4646 | int ret; | |
4647 | ||
22fe9b54 PH |
4648 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4649 | if (ret) | |
a8259075 SR |
4650 | return ret; |
4651 | ||
f2d84b65 | 4652 | if (val != 0 && val != 1) |
a8259075 | 4653 | return -EINVAL; |
f2d84b65 | 4654 | set_tracer_flags(1 << index, val); |
a8259075 SR |
4655 | |
4656 | *ppos += cnt; | |
4657 | ||
4658 | return cnt; | |
4659 | } | |
4660 | ||
a8259075 SR |
4661 | static const struct file_operations trace_options_core_fops = { |
4662 | .open = tracing_open_generic, | |
4663 | .read = trace_options_core_read, | |
4664 | .write = trace_options_core_write, | |
b444786f | 4665 | .llseek = generic_file_llseek, |
a8259075 SR |
4666 | }; |
4667 | ||
5452af66 | 4668 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 4669 | umode_t mode, |
5452af66 FW |
4670 | struct dentry *parent, |
4671 | void *data, | |
4672 | const struct file_operations *fops) | |
4673 | { | |
4674 | struct dentry *ret; | |
4675 | ||
4676 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
4677 | if (!ret) | |
4678 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
4679 | ||
4680 | return ret; | |
4681 | } | |
4682 | ||
4683 | ||
a8259075 SR |
4684 | static struct dentry *trace_options_init_dentry(void) |
4685 | { | |
4686 | struct dentry *d_tracer; | |
4687 | static struct dentry *t_options; | |
4688 | ||
4689 | if (t_options) | |
4690 | return t_options; | |
4691 | ||
4692 | d_tracer = tracing_init_dentry(); | |
4693 | if (!d_tracer) | |
4694 | return NULL; | |
4695 | ||
4696 | t_options = debugfs_create_dir("options", d_tracer); | |
4697 | if (!t_options) { | |
4698 | pr_warning("Could not create debugfs directory 'options'\n"); | |
4699 | return NULL; | |
4700 | } | |
4701 | ||
4702 | return t_options; | |
4703 | } | |
4704 | ||
577b785f SR |
4705 | static void |
4706 | create_trace_option_file(struct trace_option_dentry *topt, | |
4707 | struct tracer_flags *flags, | |
4708 | struct tracer_opt *opt) | |
4709 | { | |
4710 | struct dentry *t_options; | |
577b785f SR |
4711 | |
4712 | t_options = trace_options_init_dentry(); | |
4713 | if (!t_options) | |
4714 | return; | |
4715 | ||
4716 | topt->flags = flags; | |
4717 | topt->opt = opt; | |
4718 | ||
5452af66 | 4719 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
4720 | &trace_options_fops); |
4721 | ||
577b785f SR |
4722 | } |
4723 | ||
4724 | static struct trace_option_dentry * | |
4725 | create_trace_option_files(struct tracer *tracer) | |
4726 | { | |
4727 | struct trace_option_dentry *topts; | |
4728 | struct tracer_flags *flags; | |
4729 | struct tracer_opt *opts; | |
4730 | int cnt; | |
4731 | ||
4732 | if (!tracer) | |
4733 | return NULL; | |
4734 | ||
4735 | flags = tracer->flags; | |
4736 | ||
4737 | if (!flags || !flags->opts) | |
4738 | return NULL; | |
4739 | ||
4740 | opts = flags->opts; | |
4741 | ||
4742 | for (cnt = 0; opts[cnt].name; cnt++) | |
4743 | ; | |
4744 | ||
0cfe8245 | 4745 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
4746 | if (!topts) |
4747 | return NULL; | |
4748 | ||
4749 | for (cnt = 0; opts[cnt].name; cnt++) | |
4750 | create_trace_option_file(&topts[cnt], flags, | |
4751 | &opts[cnt]); | |
4752 | ||
4753 | return topts; | |
4754 | } | |
4755 | ||
4756 | static void | |
4757 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
4758 | { | |
4759 | int cnt; | |
4760 | ||
4761 | if (!topts) | |
4762 | return; | |
4763 | ||
4764 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
4765 | if (topts[cnt].entry) | |
4766 | debugfs_remove(topts[cnt].entry); | |
4767 | } | |
4768 | ||
4769 | kfree(topts); | |
4770 | } | |
4771 | ||
a8259075 SR |
4772 | static struct dentry * |
4773 | create_trace_option_core_file(const char *option, long index) | |
4774 | { | |
4775 | struct dentry *t_options; | |
a8259075 SR |
4776 | |
4777 | t_options = trace_options_init_dentry(); | |
4778 | if (!t_options) | |
4779 | return NULL; | |
4780 | ||
5452af66 | 4781 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 4782 | &trace_options_core_fops); |
a8259075 SR |
4783 | } |
4784 | ||
4785 | static __init void create_trace_options_dir(void) | |
4786 | { | |
4787 | struct dentry *t_options; | |
a8259075 SR |
4788 | int i; |
4789 | ||
4790 | t_options = trace_options_init_dentry(); | |
4791 | if (!t_options) | |
4792 | return; | |
4793 | ||
5452af66 FW |
4794 | for (i = 0; trace_options[i]; i++) |
4795 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4796 | } |
4797 | ||
499e5470 SR |
4798 | static ssize_t |
4799 | rb_simple_read(struct file *filp, char __user *ubuf, | |
4800 | size_t cnt, loff_t *ppos) | |
4801 | { | |
4802 | struct ring_buffer *buffer = filp->private_data; | |
4803 | char buf[64]; | |
4804 | int r; | |
4805 | ||
4806 | if (buffer) | |
4807 | r = ring_buffer_record_is_on(buffer); | |
4808 | else | |
4809 | r = 0; | |
4810 | ||
4811 | r = sprintf(buf, "%d\n", r); | |
4812 | ||
4813 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4814 | } | |
4815 | ||
4816 | static ssize_t | |
4817 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
4818 | size_t cnt, loff_t *ppos) | |
4819 | { | |
4820 | struct ring_buffer *buffer = filp->private_data; | |
4821 | unsigned long val; | |
4822 | int ret; | |
4823 | ||
4824 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
4825 | if (ret) | |
4826 | return ret; | |
4827 | ||
4828 | if (buffer) { | |
4829 | if (val) | |
4830 | ring_buffer_record_on(buffer); | |
4831 | else | |
4832 | ring_buffer_record_off(buffer); | |
4833 | } | |
4834 | ||
4835 | (*ppos)++; | |
4836 | ||
4837 | return cnt; | |
4838 | } | |
4839 | ||
4840 | static const struct file_operations rb_simple_fops = { | |
4841 | .open = tracing_open_generic, | |
4842 | .read = rb_simple_read, | |
4843 | .write = rb_simple_write, | |
4844 | .llseek = default_llseek, | |
4845 | }; | |
4846 | ||
b5ad384e | 4847 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4848 | { |
4849 | struct dentry *d_tracer; | |
b04cc6b1 | 4850 | int cpu; |
bc0c38d1 | 4851 | |
7e53bd42 LJ |
4852 | trace_access_lock_init(); |
4853 | ||
bc0c38d1 SR |
4854 | d_tracer = tracing_init_dentry(); |
4855 | ||
5452af66 FW |
4856 | trace_create_file("tracing_enabled", 0644, d_tracer, |
4857 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 4858 | |
5452af66 FW |
4859 | trace_create_file("trace_options", 0644, d_tracer, |
4860 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4861 | |
5452af66 FW |
4862 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4863 | NULL, &tracing_cpumask_fops); | |
4864 | ||
4865 | trace_create_file("trace", 0644, d_tracer, | |
4866 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 4867 | |
5452af66 FW |
4868 | trace_create_file("available_tracers", 0444, d_tracer, |
4869 | &global_trace, &show_traces_fops); | |
4870 | ||
339ae5d3 | 4871 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4872 | &global_trace, &set_tracer_fops); |
4873 | ||
5d4a9dba | 4874 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
4875 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
4876 | &tracing_max_latency, &tracing_max_lat_fops); | |
0e950173 | 4877 | #endif |
5452af66 FW |
4878 | |
4879 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4880 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 4881 | |
339ae5d3 | 4882 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4883 | NULL, &tracing_readme_fops); |
4884 | ||
4885 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4886 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4887 | |
4888 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
438ced17 | 4889 | (void *) RING_BUFFER_ALL_CPUS, &tracing_entries_fops); |
5452af66 | 4890 | |
f81ab074 VN |
4891 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, |
4892 | &global_trace, &tracing_total_entries_fops); | |
4893 | ||
4f271a2a VN |
4894 | trace_create_file("free_buffer", 0644, d_tracer, |
4895 | &global_trace, &tracing_free_buffer_fops); | |
4896 | ||
5452af66 FW |
4897 | trace_create_file("trace_marker", 0220, d_tracer, |
4898 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4899 | |
69abe6a5 AP |
4900 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4901 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 4902 | |
5079f326 Z |
4903 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
4904 | &trace_clock_fops); | |
4905 | ||
499e5470 SR |
4906 | trace_create_file("tracing_on", 0644, d_tracer, |
4907 | global_trace.buffer, &rb_simple_fops); | |
4908 | ||
bc0c38d1 | 4909 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4910 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4911 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4912 | #endif |
b04cc6b1 | 4913 | |
5452af66 FW |
4914 | create_trace_options_dir(); |
4915 | ||
b04cc6b1 FW |
4916 | for_each_tracing_cpu(cpu) |
4917 | tracing_init_debugfs_percpu(cpu); | |
4918 | ||
b5ad384e | 4919 | return 0; |
bc0c38d1 SR |
4920 | } |
4921 | ||
3f5a54e3 SR |
4922 | static int trace_panic_handler(struct notifier_block *this, |
4923 | unsigned long event, void *unused) | |
4924 | { | |
944ac425 | 4925 | if (ftrace_dump_on_oops) |
cecbca96 | 4926 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4927 | return NOTIFY_OK; |
4928 | } | |
4929 | ||
4930 | static struct notifier_block trace_panic_notifier = { | |
4931 | .notifier_call = trace_panic_handler, | |
4932 | .next = NULL, | |
4933 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4934 | }; | |
4935 | ||
4936 | static int trace_die_handler(struct notifier_block *self, | |
4937 | unsigned long val, | |
4938 | void *data) | |
4939 | { | |
4940 | switch (val) { | |
4941 | case DIE_OOPS: | |
944ac425 | 4942 | if (ftrace_dump_on_oops) |
cecbca96 | 4943 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
4944 | break; |
4945 | default: | |
4946 | break; | |
4947 | } | |
4948 | return NOTIFY_OK; | |
4949 | } | |
4950 | ||
4951 | static struct notifier_block trace_die_notifier = { | |
4952 | .notifier_call = trace_die_handler, | |
4953 | .priority = 200 | |
4954 | }; | |
4955 | ||
4956 | /* | |
4957 | * printk is set to max of 1024, we really don't need it that big. | |
4958 | * Nothing should be printing 1000 characters anyway. | |
4959 | */ | |
4960 | #define TRACE_MAX_PRINT 1000 | |
4961 | ||
4962 | /* | |
4963 | * Define here KERN_TRACE so that we have one place to modify | |
4964 | * it if we decide to change what log level the ftrace dump | |
4965 | * should be at. | |
4966 | */ | |
428aee14 | 4967 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 4968 | |
955b61e5 | 4969 | void |
3f5a54e3 SR |
4970 | trace_printk_seq(struct trace_seq *s) |
4971 | { | |
4972 | /* Probably should print a warning here. */ | |
4973 | if (s->len >= 1000) | |
4974 | s->len = 1000; | |
4975 | ||
4976 | /* should be zero ended, but we are paranoid. */ | |
4977 | s->buffer[s->len] = 0; | |
4978 | ||
4979 | printk(KERN_TRACE "%s", s->buffer); | |
4980 | ||
f9520750 | 4981 | trace_seq_init(s); |
3f5a54e3 SR |
4982 | } |
4983 | ||
955b61e5 JW |
4984 | void trace_init_global_iter(struct trace_iterator *iter) |
4985 | { | |
4986 | iter->tr = &global_trace; | |
4987 | iter->trace = current_trace; | |
4988 | iter->cpu_file = TRACE_PIPE_ALL_CPU; | |
4989 | } | |
4990 | ||
cecbca96 FW |
4991 | static void |
4992 | __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode) | |
3f5a54e3 | 4993 | { |
445c8951 | 4994 | static arch_spinlock_t ftrace_dump_lock = |
edc35bd7 | 4995 | (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
3f5a54e3 SR |
4996 | /* use static because iter can be a bit big for the stack */ |
4997 | static struct trace_iterator iter; | |
cf586b61 | 4998 | unsigned int old_userobj; |
3f5a54e3 | 4999 | static int dump_ran; |
d769041f SR |
5000 | unsigned long flags; |
5001 | int cnt = 0, cpu; | |
3f5a54e3 SR |
5002 | |
5003 | /* only one dump */ | |
cd891ae0 | 5004 | local_irq_save(flags); |
0199c4e6 | 5005 | arch_spin_lock(&ftrace_dump_lock); |
3f5a54e3 SR |
5006 | if (dump_ran) |
5007 | goto out; | |
5008 | ||
5009 | dump_ran = 1; | |
5010 | ||
0ee6b6cf | 5011 | tracing_off(); |
cf586b61 | 5012 | |
e0a413f6 SR |
5013 | /* Did function tracer already get disabled? */ |
5014 | if (ftrace_is_dead()) { | |
5015 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
5016 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
5017 | } | |
5018 | ||
cf586b61 FW |
5019 | if (disable_tracing) |
5020 | ftrace_kill(); | |
3f5a54e3 | 5021 | |
955b61e5 JW |
5022 | trace_init_global_iter(&iter); |
5023 | ||
d769041f | 5024 | for_each_tracing_cpu(cpu) { |
955b61e5 | 5025 | atomic_inc(&iter.tr->data[cpu]->disabled); |
d769041f SR |
5026 | } |
5027 | ||
cf586b61 FW |
5028 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
5029 | ||
b54d3de9 TE |
5030 | /* don't look at user memory in panic mode */ |
5031 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
5032 | ||
e543ad76 | 5033 | /* Simulate the iterator */ |
3f5a54e3 SR |
5034 | iter.tr = &global_trace; |
5035 | iter.trace = current_trace; | |
cecbca96 FW |
5036 | |
5037 | switch (oops_dump_mode) { | |
5038 | case DUMP_ALL: | |
5039 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
5040 | break; | |
5041 | case DUMP_ORIG: | |
5042 | iter.cpu_file = raw_smp_processor_id(); | |
5043 | break; | |
5044 | case DUMP_NONE: | |
5045 | goto out_enable; | |
5046 | default: | |
5047 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
5048 | iter.cpu_file = TRACE_PIPE_ALL_CPU; | |
5049 | } | |
5050 | ||
5051 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 SR |
5052 | |
5053 | /* | |
5054 | * We need to stop all tracing on all CPUS to read the | |
5055 | * the next buffer. This is a bit expensive, but is | |
5056 | * not done often. We fill all what we can read, | |
5057 | * and then release the locks again. | |
5058 | */ | |
5059 | ||
3f5a54e3 SR |
5060 | while (!trace_empty(&iter)) { |
5061 | ||
5062 | if (!cnt) | |
5063 | printk(KERN_TRACE "---------------------------------\n"); | |
5064 | ||
5065 | cnt++; | |
5066 | ||
5067 | /* reset all but tr, trace, and overruns */ | |
5068 | memset(&iter.seq, 0, | |
5069 | sizeof(struct trace_iterator) - | |
5070 | offsetof(struct trace_iterator, seq)); | |
5071 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
5072 | iter.pos = -1; | |
5073 | ||
955b61e5 | 5074 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
5075 | int ret; |
5076 | ||
5077 | ret = print_trace_line(&iter); | |
5078 | if (ret != TRACE_TYPE_NO_CONSUME) | |
5079 | trace_consume(&iter); | |
3f5a54e3 | 5080 | } |
b892e5c8 | 5081 | touch_nmi_watchdog(); |
3f5a54e3 SR |
5082 | |
5083 | trace_printk_seq(&iter.seq); | |
5084 | } | |
5085 | ||
5086 | if (!cnt) | |
5087 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
5088 | else | |
5089 | printk(KERN_TRACE "---------------------------------\n"); | |
5090 | ||
cecbca96 | 5091 | out_enable: |
cf586b61 FW |
5092 | /* Re-enable tracing if requested */ |
5093 | if (!disable_tracing) { | |
5094 | trace_flags |= old_userobj; | |
5095 | ||
5096 | for_each_tracing_cpu(cpu) { | |
955b61e5 | 5097 | atomic_dec(&iter.tr->data[cpu]->disabled); |
cf586b61 FW |
5098 | } |
5099 | tracing_on(); | |
5100 | } | |
5101 | ||
3f5a54e3 | 5102 | out: |
0199c4e6 | 5103 | arch_spin_unlock(&ftrace_dump_lock); |
cd891ae0 | 5104 | local_irq_restore(flags); |
3f5a54e3 SR |
5105 | } |
5106 | ||
cf586b61 | 5107 | /* By default: disable tracing after the dump */ |
cecbca96 | 5108 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
cf586b61 | 5109 | { |
cecbca96 | 5110 | __ftrace_dump(true, oops_dump_mode); |
cf586b61 | 5111 | } |
a8eecf22 | 5112 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 5113 | |
3928a8a2 | 5114 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 5115 | { |
73c5162a | 5116 | int ring_buf_size; |
750912fa | 5117 | enum ring_buffer_flags rb_flags; |
4c11d7ae | 5118 | int i; |
9e01c1b7 | 5119 | int ret = -ENOMEM; |
4c11d7ae | 5120 | |
750912fa | 5121 | |
9e01c1b7 RR |
5122 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
5123 | goto out; | |
5124 | ||
5125 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
5126 | goto out_free_buffer_mask; | |
4c11d7ae | 5127 | |
07d777fe SR |
5128 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
5129 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
5130 | trace_printk_init_buffers(); | |
5131 | ||
73c5162a SR |
5132 | /* To save memory, keep the ring buffer size to its minimum */ |
5133 | if (ring_buffer_expanded) | |
5134 | ring_buf_size = trace_buf_size; | |
5135 | else | |
5136 | ring_buf_size = 1; | |
5137 | ||
750912fa DS |
5138 | rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; |
5139 | ||
9e01c1b7 RR |
5140 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
5141 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
5142 | ||
5143 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
750912fa | 5144 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, rb_flags); |
3928a8a2 SR |
5145 | if (!global_trace.buffer) { |
5146 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
5147 | WARN_ON(1); | |
9e01c1b7 | 5148 | goto out_free_cpumask; |
4c11d7ae | 5149 | } |
499e5470 SR |
5150 | if (global_trace.buffer_disabled) |
5151 | tracing_off(); | |
4c11d7ae | 5152 | |
9e01c1b7 | 5153 | |
4c11d7ae | 5154 | #ifdef CONFIG_TRACER_MAX_TRACE |
750912fa | 5155 | max_tr.buffer = ring_buffer_alloc(1, rb_flags); |
3928a8a2 SR |
5156 | if (!max_tr.buffer) { |
5157 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
5158 | WARN_ON(1); | |
5159 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 5160 | goto out_free_cpumask; |
4c11d7ae | 5161 | } |
a98a3c3f | 5162 | #endif |
ab46428c | 5163 | |
4c11d7ae | 5164 | /* Allocate the first page for all buffers */ |
ab46428c | 5165 | for_each_tracing_cpu(i) { |
566b0aaf | 5166 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
9705f69e | 5167 | max_tr.data[i] = &per_cpu(max_tr_data, i); |
4c11d7ae | 5168 | } |
438ced17 VN |
5169 | |
5170 | set_buffer_entries(&global_trace, ring_buf_size); | |
5171 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5172 | set_buffer_entries(&max_tr, 1); | |
5173 | #endif | |
bc0c38d1 | 5174 | |
bc0c38d1 SR |
5175 | trace_init_cmdlines(); |
5176 | ||
43a15386 | 5177 | register_tracer(&nop_trace); |
79fb0768 | 5178 | current_trace = &nop_trace; |
60a11774 SR |
5179 | /* All seems OK, enable tracing */ |
5180 | tracing_disabled = 0; | |
3928a8a2 | 5181 | |
3f5a54e3 SR |
5182 | atomic_notifier_chain_register(&panic_notifier_list, |
5183 | &trace_panic_notifier); | |
5184 | ||
5185 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
5186 | |
5187 | return 0; | |
3f5a54e3 | 5188 | |
9e01c1b7 RR |
5189 | out_free_cpumask: |
5190 | free_cpumask_var(tracing_cpumask); | |
5191 | out_free_buffer_mask: | |
5192 | free_cpumask_var(tracing_buffer_mask); | |
5193 | out: | |
5194 | return ret; | |
bc0c38d1 | 5195 | } |
b2821ae6 SR |
5196 | |
5197 | __init static int clear_boot_tracer(void) | |
5198 | { | |
5199 | /* | |
5200 | * The default tracer at boot buffer is an init section. | |
5201 | * This function is called in lateinit. If we did not | |
5202 | * find the boot tracer, then clear it out, to prevent | |
5203 | * later registration from accessing the buffer that is | |
5204 | * about to be freed. | |
5205 | */ | |
5206 | if (!default_bootup_tracer) | |
5207 | return 0; | |
5208 | ||
5209 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
5210 | default_bootup_tracer); | |
5211 | default_bootup_tracer = NULL; | |
5212 | ||
5213 | return 0; | |
5214 | } | |
5215 | ||
b5ad384e FW |
5216 | early_initcall(tracer_alloc_buffers); |
5217 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 5218 | late_initcall(clear_boot_tracer); |