Commit | Line | Data |
---|---|---|
bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
14 | #include <linux/utsrelease.h> | |
15 | #include <linux/kallsyms.h> | |
16 | #include <linux/seq_file.h> | |
3f5a54e3 | 17 | #include <linux/notifier.h> |
bc0c38d1 | 18 | #include <linux/debugfs.h> |
4c11d7ae | 19 | #include <linux/pagemap.h> |
bc0c38d1 SR |
20 | #include <linux/hardirq.h> |
21 | #include <linux/linkage.h> | |
22 | #include <linux/uaccess.h> | |
23 | #include <linux/ftrace.h> | |
24 | #include <linux/module.h> | |
25 | #include <linux/percpu.h> | |
3f5a54e3 | 26 | #include <linux/kdebug.h> |
bc0c38d1 SR |
27 | #include <linux/ctype.h> |
28 | #include <linux/init.h> | |
2a2cc8f7 | 29 | #include <linux/poll.h> |
bc0c38d1 SR |
30 | #include <linux/gfp.h> |
31 | #include <linux/fs.h> | |
76094a2c | 32 | #include <linux/kprobes.h> |
3eefae99 | 33 | #include <linux/writeback.h> |
bc0c38d1 | 34 | |
86387f7e | 35 | #include <linux/stacktrace.h> |
3928a8a2 | 36 | #include <linux/ring_buffer.h> |
21798a84 | 37 | #include <linux/irqflags.h> |
86387f7e | 38 | |
bc0c38d1 | 39 | #include "trace.h" |
f0868d1e | 40 | #include "trace_output.h" |
bc0c38d1 | 41 | |
3928a8a2 SR |
42 | #define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE) |
43 | ||
745b1626 | 44 | unsigned long __read_mostly tracing_max_latency; |
bc0c38d1 SR |
45 | unsigned long __read_mostly tracing_thresh; |
46 | ||
8e1b82e0 FW |
47 | /* |
48 | * We need to change this state when a selftest is running. | |
ff32504f FW |
49 | * A selftest will lurk into the ring-buffer to count the |
50 | * entries inserted during the selftest although some concurrent | |
51 | * insertions into the ring-buffer such as ftrace_printk could occurred | |
52 | * at the same time, giving false positive or negative results. | |
53 | */ | |
8e1b82e0 | 54 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 55 | |
adf9f195 FW |
56 | /* For tracers that don't implement custom flags */ |
57 | static struct tracer_opt dummy_tracer_opt[] = { | |
58 | { } | |
59 | }; | |
60 | ||
61 | static struct tracer_flags dummy_tracer_flags = { | |
62 | .val = 0, | |
63 | .opts = dummy_tracer_opt | |
64 | }; | |
65 | ||
66 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
67 | { | |
68 | return 0; | |
69 | } | |
0f048701 SR |
70 | |
71 | /* | |
72 | * Kill all tracing for good (never come back). | |
73 | * It is initialized to 1 but will turn to zero if the initialization | |
74 | * of the tracer is successful. But that is the only place that sets | |
75 | * this back to zero. | |
76 | */ | |
77 | int tracing_disabled = 1; | |
78 | ||
d769041f SR |
79 | static DEFINE_PER_CPU(local_t, ftrace_cpu_disabled); |
80 | ||
81 | static inline void ftrace_disable_cpu(void) | |
82 | { | |
83 | preempt_disable(); | |
84 | local_inc(&__get_cpu_var(ftrace_cpu_disabled)); | |
85 | } | |
86 | ||
87 | static inline void ftrace_enable_cpu(void) | |
88 | { | |
89 | local_dec(&__get_cpu_var(ftrace_cpu_disabled)); | |
90 | preempt_enable(); | |
91 | } | |
92 | ||
9e01c1b7 | 93 | static cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c SR |
94 | |
95 | #define for_each_tracing_cpu(cpu) \ | |
9e01c1b7 | 96 | for_each_cpu(cpu, tracing_buffer_mask) |
ab46428c | 97 | |
944ac425 SR |
98 | /* |
99 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
100 | * | |
101 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
102 | * is set, then ftrace_dump is called. This will output the contents | |
103 | * of the ftrace buffers to the console. This is very useful for | |
104 | * capturing traces that lead to crashes and outputing it to a | |
105 | * serial console. | |
106 | * | |
107 | * It is default off, but you can enable it with either specifying | |
108 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
109 | * /proc/sys/kernel/ftrace_dump_on_oops to true. | |
110 | */ | |
111 | int ftrace_dump_on_oops; | |
112 | ||
d9e54076 PZ |
113 | static int tracing_set_tracer(char *buf); |
114 | ||
115 | static int __init set_ftrace(char *str) | |
116 | { | |
117 | tracing_set_tracer(str); | |
118 | return 1; | |
119 | } | |
120 | __setup("ftrace", set_ftrace); | |
121 | ||
944ac425 SR |
122 | static int __init set_ftrace_dump_on_oops(char *str) |
123 | { | |
124 | ftrace_dump_on_oops = 1; | |
125 | return 1; | |
126 | } | |
127 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 128 | |
72829bc3 | 129 | long |
bc0c38d1 SR |
130 | ns2usecs(cycle_t nsec) |
131 | { | |
132 | nsec += 500; | |
133 | do_div(nsec, 1000); | |
134 | return nsec; | |
135 | } | |
136 | ||
e309b41d | 137 | cycle_t ftrace_now(int cpu) |
750ed1a4 | 138 | { |
3928a8a2 SR |
139 | u64 ts = ring_buffer_time_stamp(cpu); |
140 | ring_buffer_normalize_time_stamp(cpu, &ts); | |
141 | return ts; | |
750ed1a4 IM |
142 | } |
143 | ||
4fcdae83 SR |
144 | /* |
145 | * The global_trace is the descriptor that holds the tracing | |
146 | * buffers for the live tracing. For each CPU, it contains | |
147 | * a link list of pages that will store trace entries. The | |
148 | * page descriptor of the pages in the memory is used to hold | |
149 | * the link list by linking the lru item in the page descriptor | |
150 | * to each of the pages in the buffer per CPU. | |
151 | * | |
152 | * For each active CPU there is a data field that holds the | |
153 | * pages for the buffer for that CPU. Each CPU has the same number | |
154 | * of pages allocated for its buffer. | |
155 | */ | |
bc0c38d1 SR |
156 | static struct trace_array global_trace; |
157 | ||
158 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
159 | ||
4fcdae83 SR |
160 | /* |
161 | * The max_tr is used to snapshot the global_trace when a maximum | |
162 | * latency is reached. Some tracers will use this to store a maximum | |
163 | * trace while it continues examining live traces. | |
164 | * | |
165 | * The buffers for the max_tr are set up the same as the global_trace. | |
166 | * When a snapshot is taken, the link list of the max_tr is swapped | |
167 | * with the link list of the global_trace and the buffers are reset for | |
168 | * the global_trace so the tracing can continue. | |
169 | */ | |
bc0c38d1 SR |
170 | static struct trace_array max_tr; |
171 | ||
172 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
173 | ||
4fcdae83 | 174 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 175 | static int tracer_enabled = 1; |
4fcdae83 | 176 | |
9036990d SR |
177 | /** |
178 | * tracing_is_enabled - return tracer_enabled status | |
179 | * | |
180 | * This function is used by other tracers to know the status | |
181 | * of the tracer_enabled flag. Tracers may use this function | |
182 | * to know if it should enable their features when starting | |
183 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
184 | */ | |
185 | int tracing_is_enabled(void) | |
186 | { | |
187 | return tracer_enabled; | |
188 | } | |
189 | ||
4fcdae83 | 190 | /* |
3928a8a2 SR |
191 | * trace_buf_size is the size in bytes that is allocated |
192 | * for a buffer. Note, the number of bytes is always rounded | |
193 | * to page size. | |
3f5a54e3 SR |
194 | * |
195 | * This number is purposely set to a low number of 16384. | |
196 | * If the dump on oops happens, it will be much appreciated | |
197 | * to not have to wait for all that output. Anyway this can be | |
198 | * boot time and run time configurable. | |
4fcdae83 | 199 | */ |
3928a8a2 | 200 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 201 | |
3928a8a2 | 202 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 203 | |
4fcdae83 | 204 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 205 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
206 | |
207 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 208 | static struct tracer *current_trace __read_mostly; |
4fcdae83 SR |
209 | |
210 | /* | |
211 | * max_tracer_type_len is used to simplify the allocating of | |
212 | * buffers to read userspace tracer names. We keep track of | |
213 | * the longest tracer name registered. | |
214 | */ | |
bc0c38d1 SR |
215 | static int max_tracer_type_len; |
216 | ||
4fcdae83 SR |
217 | /* |
218 | * trace_types_lock is used to protect the trace_types list. | |
219 | * This lock is also used to keep user access serialized. | |
220 | * Accesses from userspace will grab this lock while userspace | |
221 | * activities happen inside the kernel. | |
222 | */ | |
bc0c38d1 | 223 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
224 | |
225 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
226 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
227 | ||
ee6bce52 | 228 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 229 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
c4a8e8be | 230 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO; |
4e655519 | 231 | |
4fcdae83 SR |
232 | /** |
233 | * trace_wake_up - wake up tasks waiting for trace input | |
234 | * | |
235 | * Simply wakes up any task that is blocked on the trace_wait | |
236 | * queue. These is used with trace_poll for tasks polling the trace. | |
237 | */ | |
4e655519 IM |
238 | void trace_wake_up(void) |
239 | { | |
017730c1 IM |
240 | /* |
241 | * The runqueue_is_locked() can fail, but this is the best we | |
242 | * have for now: | |
243 | */ | |
244 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
245 | wake_up(&trace_wait); |
246 | } | |
bc0c38d1 | 247 | |
3928a8a2 | 248 | static int __init set_buf_size(char *str) |
bc0c38d1 | 249 | { |
3928a8a2 | 250 | unsigned long buf_size; |
c6caeeb1 SR |
251 | int ret; |
252 | ||
bc0c38d1 SR |
253 | if (!str) |
254 | return 0; | |
3928a8a2 | 255 | ret = strict_strtoul(str, 0, &buf_size); |
c6caeeb1 | 256 | /* nr_entries can not be zero */ |
3928a8a2 | 257 | if (ret < 0 || buf_size == 0) |
c6caeeb1 | 258 | return 0; |
3928a8a2 | 259 | trace_buf_size = buf_size; |
bc0c38d1 SR |
260 | return 1; |
261 | } | |
3928a8a2 | 262 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 263 | |
57f50be1 SR |
264 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
265 | { | |
266 | return nsecs / 1000; | |
267 | } | |
268 | ||
4fcdae83 | 269 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
270 | static const char *trace_options[] = { |
271 | "print-parent", | |
272 | "sym-offset", | |
273 | "sym-addr", | |
274 | "verbose", | |
f9896bf3 | 275 | "raw", |
5e3ca0ec | 276 | "hex", |
cb0f12aa | 277 | "bin", |
2a2cc8f7 | 278 | "block", |
86387f7e | 279 | "stacktrace", |
4ac3ba41 | 280 | "sched-tree", |
f09ce573 | 281 | "ftrace_printk", |
b2a866f9 | 282 | "ftrace_preempt", |
9f029e83 | 283 | "branch", |
12ef7d44 | 284 | "annotate", |
02b67518 | 285 | "userstacktrace", |
b54d3de9 | 286 | "sym-userobj", |
66896a85 | 287 | "printk-msg-only", |
c4a8e8be | 288 | "context-info", |
bc0c38d1 SR |
289 | NULL |
290 | }; | |
291 | ||
4fcdae83 SR |
292 | /* |
293 | * ftrace_max_lock is used to protect the swapping of buffers | |
294 | * when taking a max snapshot. The buffers themselves are | |
295 | * protected by per_cpu spinlocks. But the action of the swap | |
296 | * needs its own lock. | |
297 | * | |
298 | * This is defined as a raw_spinlock_t in order to help | |
299 | * with performance when lockdep debugging is enabled. | |
300 | */ | |
92205c23 SR |
301 | static raw_spinlock_t ftrace_max_lock = |
302 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
bc0c38d1 SR |
303 | |
304 | /* | |
305 | * Copy the new maximum trace into the separate maximum-trace | |
306 | * structure. (this way the maximum trace is permanently saved, | |
307 | * for later retrieval via /debugfs/tracing/latency_trace) | |
308 | */ | |
e309b41d | 309 | static void |
bc0c38d1 SR |
310 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
311 | { | |
312 | struct trace_array_cpu *data = tr->data[cpu]; | |
313 | ||
314 | max_tr.cpu = cpu; | |
315 | max_tr.time_start = data->preempt_timestamp; | |
316 | ||
317 | data = max_tr.data[cpu]; | |
318 | data->saved_latency = tracing_max_latency; | |
319 | ||
320 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
321 | data->pid = tsk->pid; | |
b6dff3ec | 322 | data->uid = task_uid(tsk); |
bc0c38d1 SR |
323 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
324 | data->policy = tsk->policy; | |
325 | data->rt_priority = tsk->rt_priority; | |
326 | ||
327 | /* record this tasks comm */ | |
328 | tracing_record_cmdline(current); | |
329 | } | |
330 | ||
e309b41d | 331 | static void |
214023c3 SR |
332 | trace_seq_reset(struct trace_seq *s) |
333 | { | |
334 | s->len = 0; | |
6c6c2796 PP |
335 | s->readpos = 0; |
336 | } | |
337 | ||
338 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) | |
339 | { | |
340 | int len; | |
341 | int ret; | |
342 | ||
343 | if (s->len <= s->readpos) | |
344 | return -EBUSY; | |
345 | ||
346 | len = s->len - s->readpos; | |
347 | if (cnt > len) | |
348 | cnt = len; | |
349 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
350 | if (ret) | |
351 | return -EFAULT; | |
352 | ||
353 | s->readpos += len; | |
354 | return cnt; | |
214023c3 SR |
355 | } |
356 | ||
e309b41d | 357 | static void |
214023c3 SR |
358 | trace_print_seq(struct seq_file *m, struct trace_seq *s) |
359 | { | |
360 | int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; | |
361 | ||
362 | s->buffer[len] = 0; | |
363 | seq_puts(m, s->buffer); | |
364 | ||
365 | trace_seq_reset(s); | |
366 | } | |
367 | ||
4fcdae83 SR |
368 | /** |
369 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
370 | * @tr: tracer | |
371 | * @tsk: the task with the latency | |
372 | * @cpu: The cpu that initiated the trace. | |
373 | * | |
374 | * Flip the buffers between the @tr and the max_tr and record information | |
375 | * about which task was the cause of this latency. | |
376 | */ | |
e309b41d | 377 | void |
bc0c38d1 SR |
378 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
379 | { | |
3928a8a2 | 380 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 381 | |
4c11d7ae | 382 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 383 | __raw_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
384 | |
385 | tr->buffer = max_tr.buffer; | |
386 | max_tr.buffer = buf; | |
387 | ||
d769041f | 388 | ftrace_disable_cpu(); |
3928a8a2 | 389 | ring_buffer_reset(tr->buffer); |
d769041f | 390 | ftrace_enable_cpu(); |
bc0c38d1 SR |
391 | |
392 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 393 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
394 | } |
395 | ||
396 | /** | |
397 | * update_max_tr_single - only copy one trace over, and reset the rest | |
398 | * @tr - tracer | |
399 | * @tsk - task with the latency | |
400 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
401 | * |
402 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 403 | */ |
e309b41d | 404 | void |
bc0c38d1 SR |
405 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
406 | { | |
3928a8a2 | 407 | int ret; |
bc0c38d1 | 408 | |
4c11d7ae | 409 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 410 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 411 | |
d769041f SR |
412 | ftrace_disable_cpu(); |
413 | ||
3928a8a2 SR |
414 | ring_buffer_reset(max_tr.buffer); |
415 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); | |
416 | ||
d769041f SR |
417 | ftrace_enable_cpu(); |
418 | ||
97b17efe | 419 | WARN_ON_ONCE(ret && ret != -EAGAIN); |
bc0c38d1 SR |
420 | |
421 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 422 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
423 | } |
424 | ||
4fcdae83 SR |
425 | /** |
426 | * register_tracer - register a tracer with the ftrace system. | |
427 | * @type - the plugin for the tracer | |
428 | * | |
429 | * Register a new plugin tracer. | |
430 | */ | |
bc0c38d1 SR |
431 | int register_tracer(struct tracer *type) |
432 | { | |
433 | struct tracer *t; | |
434 | int len; | |
435 | int ret = 0; | |
436 | ||
437 | if (!type->name) { | |
438 | pr_info("Tracer must have a name\n"); | |
439 | return -1; | |
440 | } | |
441 | ||
86fa2f60 IM |
442 | /* |
443 | * When this gets called we hold the BKL which means that | |
444 | * preemption is disabled. Various trace selftests however | |
445 | * need to disable and enable preemption for successful tests. | |
446 | * So we drop the BKL here and grab it after the tests again. | |
447 | */ | |
448 | unlock_kernel(); | |
bc0c38d1 | 449 | mutex_lock(&trace_types_lock); |
86fa2f60 | 450 | |
8e1b82e0 FW |
451 | tracing_selftest_running = true; |
452 | ||
bc0c38d1 SR |
453 | for (t = trace_types; t; t = t->next) { |
454 | if (strcmp(type->name, t->name) == 0) { | |
455 | /* already found */ | |
456 | pr_info("Trace %s already registered\n", | |
457 | type->name); | |
458 | ret = -1; | |
459 | goto out; | |
460 | } | |
461 | } | |
462 | ||
adf9f195 FW |
463 | if (!type->set_flag) |
464 | type->set_flag = &dummy_set_flag; | |
465 | if (!type->flags) | |
466 | type->flags = &dummy_tracer_flags; | |
467 | else | |
468 | if (!type->flags->opts) | |
469 | type->flags->opts = dummy_tracer_opt; | |
470 | ||
60a11774 SR |
471 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
472 | if (type->selftest) { | |
473 | struct tracer *saved_tracer = current_trace; | |
60a11774 | 474 | struct trace_array *tr = &global_trace; |
60a11774 | 475 | int i; |
ff32504f | 476 | |
60a11774 SR |
477 | /* |
478 | * Run a selftest on this tracer. | |
479 | * Here we reset the trace buffer, and set the current | |
480 | * tracer to be this tracer. The tracer can then run some | |
481 | * internal tracing to verify that everything is in order. | |
482 | * If we fail, we do not register this tracer. | |
483 | */ | |
86fa2f60 | 484 | for_each_tracing_cpu(i) |
3928a8a2 | 485 | tracing_reset(tr, i); |
86fa2f60 | 486 | |
60a11774 | 487 | current_trace = type; |
60a11774 SR |
488 | /* the test is responsible for initializing and enabling */ |
489 | pr_info("Testing tracer %s: ", type->name); | |
490 | ret = type->selftest(type, tr); | |
491 | /* the test is responsible for resetting too */ | |
492 | current_trace = saved_tracer; | |
60a11774 SR |
493 | if (ret) { |
494 | printk(KERN_CONT "FAILED!\n"); | |
495 | goto out; | |
496 | } | |
1d4db00a | 497 | /* Only reset on passing, to avoid touching corrupted buffers */ |
86fa2f60 | 498 | for_each_tracing_cpu(i) |
3928a8a2 | 499 | tracing_reset(tr, i); |
86fa2f60 | 500 | |
60a11774 SR |
501 | printk(KERN_CONT "PASSED\n"); |
502 | } | |
503 | #endif | |
504 | ||
bc0c38d1 SR |
505 | type->next = trace_types; |
506 | trace_types = type; | |
507 | len = strlen(type->name); | |
508 | if (len > max_tracer_type_len) | |
509 | max_tracer_type_len = len; | |
60a11774 | 510 | |
bc0c38d1 | 511 | out: |
8e1b82e0 | 512 | tracing_selftest_running = false; |
bc0c38d1 | 513 | mutex_unlock(&trace_types_lock); |
86fa2f60 | 514 | lock_kernel(); |
bc0c38d1 SR |
515 | |
516 | return ret; | |
517 | } | |
518 | ||
519 | void unregister_tracer(struct tracer *type) | |
520 | { | |
521 | struct tracer **t; | |
522 | int len; | |
523 | ||
524 | mutex_lock(&trace_types_lock); | |
525 | for (t = &trace_types; *t; t = &(*t)->next) { | |
526 | if (*t == type) | |
527 | goto found; | |
528 | } | |
529 | pr_info("Trace %s not registered\n", type->name); | |
530 | goto out; | |
531 | ||
532 | found: | |
533 | *t = (*t)->next; | |
534 | if (strlen(type->name) != max_tracer_type_len) | |
535 | goto out; | |
536 | ||
537 | max_tracer_type_len = 0; | |
538 | for (t = &trace_types; *t; t = &(*t)->next) { | |
539 | len = strlen((*t)->name); | |
540 | if (len > max_tracer_type_len) | |
541 | max_tracer_type_len = len; | |
542 | } | |
543 | out: | |
544 | mutex_unlock(&trace_types_lock); | |
545 | } | |
546 | ||
3928a8a2 | 547 | void tracing_reset(struct trace_array *tr, int cpu) |
bc0c38d1 | 548 | { |
d769041f | 549 | ftrace_disable_cpu(); |
3928a8a2 | 550 | ring_buffer_reset_cpu(tr->buffer, cpu); |
d769041f | 551 | ftrace_enable_cpu(); |
bc0c38d1 SR |
552 | } |
553 | ||
213cc060 PE |
554 | void tracing_reset_online_cpus(struct trace_array *tr) |
555 | { | |
556 | int cpu; | |
557 | ||
558 | tr->time_start = ftrace_now(tr->cpu); | |
559 | ||
560 | for_each_online_cpu(cpu) | |
561 | tracing_reset(tr, cpu); | |
562 | } | |
563 | ||
bc0c38d1 SR |
564 | #define SAVED_CMDLINES 128 |
565 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
566 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
567 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
568 | static int cmdline_idx; | |
569 | static DEFINE_SPINLOCK(trace_cmdline_lock); | |
25b0b44a | 570 | |
25b0b44a SR |
571 | /* temporary disable recording */ |
572 | atomic_t trace_record_cmdline_disabled __read_mostly; | |
bc0c38d1 SR |
573 | |
574 | static void trace_init_cmdlines(void) | |
575 | { | |
576 | memset(&map_pid_to_cmdline, -1, sizeof(map_pid_to_cmdline)); | |
577 | memset(&map_cmdline_to_pid, -1, sizeof(map_cmdline_to_pid)); | |
578 | cmdline_idx = 0; | |
579 | } | |
580 | ||
0f048701 SR |
581 | static int trace_stop_count; |
582 | static DEFINE_SPINLOCK(tracing_start_lock); | |
583 | ||
69bb54ec SR |
584 | /** |
585 | * ftrace_off_permanent - disable all ftrace code permanently | |
586 | * | |
587 | * This should only be called when a serious anomally has | |
588 | * been detected. This will turn off the function tracing, | |
589 | * ring buffers, and other tracing utilites. It takes no | |
590 | * locks and can be called from any context. | |
591 | */ | |
592 | void ftrace_off_permanent(void) | |
593 | { | |
594 | tracing_disabled = 1; | |
595 | ftrace_stop(); | |
596 | tracing_off_permanent(); | |
597 | } | |
598 | ||
0f048701 SR |
599 | /** |
600 | * tracing_start - quick start of the tracer | |
601 | * | |
602 | * If tracing is enabled but was stopped by tracing_stop, | |
603 | * this will start the tracer back up. | |
604 | */ | |
605 | void tracing_start(void) | |
606 | { | |
607 | struct ring_buffer *buffer; | |
608 | unsigned long flags; | |
609 | ||
610 | if (tracing_disabled) | |
611 | return; | |
612 | ||
613 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
614 | if (--trace_stop_count) { |
615 | if (trace_stop_count < 0) { | |
616 | /* Someone screwed up their debugging */ | |
617 | WARN_ON_ONCE(1); | |
618 | trace_stop_count = 0; | |
619 | } | |
0f048701 SR |
620 | goto out; |
621 | } | |
622 | ||
623 | ||
624 | buffer = global_trace.buffer; | |
625 | if (buffer) | |
626 | ring_buffer_record_enable(buffer); | |
627 | ||
628 | buffer = max_tr.buffer; | |
629 | if (buffer) | |
630 | ring_buffer_record_enable(buffer); | |
631 | ||
632 | ftrace_start(); | |
633 | out: | |
634 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
635 | } | |
636 | ||
637 | /** | |
638 | * tracing_stop - quick stop of the tracer | |
639 | * | |
640 | * Light weight way to stop tracing. Use in conjunction with | |
641 | * tracing_start. | |
642 | */ | |
643 | void tracing_stop(void) | |
644 | { | |
645 | struct ring_buffer *buffer; | |
646 | unsigned long flags; | |
647 | ||
648 | ftrace_stop(); | |
649 | spin_lock_irqsave(&tracing_start_lock, flags); | |
650 | if (trace_stop_count++) | |
651 | goto out; | |
652 | ||
653 | buffer = global_trace.buffer; | |
654 | if (buffer) | |
655 | ring_buffer_record_disable(buffer); | |
656 | ||
657 | buffer = max_tr.buffer; | |
658 | if (buffer) | |
659 | ring_buffer_record_disable(buffer); | |
660 | ||
661 | out: | |
662 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
663 | } | |
664 | ||
e309b41d | 665 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 666 | |
e309b41d | 667 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
668 | { |
669 | unsigned map; | |
670 | unsigned idx; | |
671 | ||
672 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
673 | return; | |
674 | ||
675 | /* | |
676 | * It's not the end of the world if we don't get | |
677 | * the lock, but we also don't want to spin | |
678 | * nor do we want to disable interrupts, | |
679 | * so if we miss here, then better luck next time. | |
680 | */ | |
681 | if (!spin_trylock(&trace_cmdline_lock)) | |
682 | return; | |
683 | ||
684 | idx = map_pid_to_cmdline[tsk->pid]; | |
685 | if (idx >= SAVED_CMDLINES) { | |
686 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; | |
687 | ||
688 | map = map_cmdline_to_pid[idx]; | |
689 | if (map <= PID_MAX_DEFAULT) | |
690 | map_pid_to_cmdline[map] = (unsigned)-1; | |
691 | ||
692 | map_pid_to_cmdline[tsk->pid] = idx; | |
693 | ||
694 | cmdline_idx = idx; | |
695 | } | |
696 | ||
697 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
698 | ||
699 | spin_unlock(&trace_cmdline_lock); | |
700 | } | |
701 | ||
660c7f9b | 702 | char *trace_find_cmdline(int pid) |
bc0c38d1 SR |
703 | { |
704 | char *cmdline = "<...>"; | |
705 | unsigned map; | |
706 | ||
707 | if (!pid) | |
708 | return "<idle>"; | |
709 | ||
710 | if (pid > PID_MAX_DEFAULT) | |
711 | goto out; | |
712 | ||
713 | map = map_pid_to_cmdline[pid]; | |
714 | if (map >= SAVED_CMDLINES) | |
715 | goto out; | |
716 | ||
717 | cmdline = saved_cmdlines[map]; | |
718 | ||
719 | out: | |
720 | return cmdline; | |
721 | } | |
722 | ||
e309b41d | 723 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
724 | { |
725 | if (atomic_read(&trace_record_cmdline_disabled)) | |
726 | return; | |
727 | ||
728 | trace_save_cmdline(tsk); | |
729 | } | |
730 | ||
45dcd8b8 | 731 | void |
38697053 SR |
732 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
733 | int pc) | |
bc0c38d1 SR |
734 | { |
735 | struct task_struct *tsk = current; | |
bc0c38d1 | 736 | |
777e208d SR |
737 | entry->preempt_count = pc & 0xff; |
738 | entry->pid = (tsk) ? tsk->pid : 0; | |
b54d3de9 | 739 | entry->tgid = (tsk) ? tsk->tgid : 0; |
777e208d | 740 | entry->flags = |
9244489a | 741 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 742 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
743 | #else |
744 | TRACE_FLAG_IRQS_NOSUPPORT | | |
745 | #endif | |
bc0c38d1 SR |
746 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
747 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
748 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
749 | } | |
750 | ||
e309b41d | 751 | void |
6fb44b71 | 752 | trace_function(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
753 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
754 | int pc) | |
bc0c38d1 | 755 | { |
3928a8a2 | 756 | struct ring_buffer_event *event; |
777e208d | 757 | struct ftrace_entry *entry; |
dcb6308f | 758 | unsigned long irq_flags; |
bc0c38d1 | 759 | |
d769041f SR |
760 | /* If we are reading the ring buffer, don't trace */ |
761 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
762 | return; | |
763 | ||
3928a8a2 SR |
764 | event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), |
765 | &irq_flags); | |
766 | if (!event) | |
767 | return; | |
768 | entry = ring_buffer_event_data(event); | |
38697053 | 769 | tracing_generic_entry_update(&entry->ent, flags, pc); |
777e208d SR |
770 | entry->ent.type = TRACE_FN; |
771 | entry->ip = ip; | |
772 | entry->parent_ip = parent_ip; | |
3928a8a2 | 773 | ring_buffer_unlock_commit(tr->buffer, event, irq_flags); |
bc0c38d1 SR |
774 | } |
775 | ||
fb52607a | 776 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
287b6e68 FW |
777 | static void __trace_graph_entry(struct trace_array *tr, |
778 | struct trace_array_cpu *data, | |
779 | struct ftrace_graph_ent *trace, | |
780 | unsigned long flags, | |
781 | int pc) | |
782 | { | |
783 | struct ring_buffer_event *event; | |
784 | struct ftrace_graph_ent_entry *entry; | |
785 | unsigned long irq_flags; | |
786 | ||
787 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
788 | return; | |
789 | ||
790 | event = ring_buffer_lock_reserve(global_trace.buffer, sizeof(*entry), | |
791 | &irq_flags); | |
792 | if (!event) | |
793 | return; | |
794 | entry = ring_buffer_event_data(event); | |
795 | tracing_generic_entry_update(&entry->ent, flags, pc); | |
796 | entry->ent.type = TRACE_GRAPH_ENT; | |
797 | entry->graph_ent = *trace; | |
798 | ring_buffer_unlock_commit(global_trace.buffer, event, irq_flags); | |
799 | } | |
800 | ||
801 | static void __trace_graph_return(struct trace_array *tr, | |
15e6cb36 | 802 | struct trace_array_cpu *data, |
fb52607a | 803 | struct ftrace_graph_ret *trace, |
15e6cb36 FW |
804 | unsigned long flags, |
805 | int pc) | |
806 | { | |
807 | struct ring_buffer_event *event; | |
287b6e68 | 808 | struct ftrace_graph_ret_entry *entry; |
15e6cb36 FW |
809 | unsigned long irq_flags; |
810 | ||
811 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
812 | return; | |
813 | ||
814 | event = ring_buffer_lock_reserve(global_trace.buffer, sizeof(*entry), | |
815 | &irq_flags); | |
816 | if (!event) | |
817 | return; | |
818 | entry = ring_buffer_event_data(event); | |
819 | tracing_generic_entry_update(&entry->ent, flags, pc); | |
287b6e68 FW |
820 | entry->ent.type = TRACE_GRAPH_RET; |
821 | entry->ret = *trace; | |
15e6cb36 FW |
822 | ring_buffer_unlock_commit(global_trace.buffer, event, irq_flags); |
823 | } | |
824 | #endif | |
825 | ||
e309b41d | 826 | void |
2e0f5761 | 827 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
828 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
829 | int pc) | |
2e0f5761 IM |
830 | { |
831 | if (likely(!atomic_read(&data->disabled))) | |
38697053 | 832 | trace_function(tr, data, ip, parent_ip, flags, pc); |
2e0f5761 IM |
833 | } |
834 | ||
53614991 SR |
835 | static void __ftrace_trace_stack(struct trace_array *tr, |
836 | struct trace_array_cpu *data, | |
837 | unsigned long flags, | |
838 | int skip, int pc) | |
86387f7e | 839 | { |
c2c80529 | 840 | #ifdef CONFIG_STACKTRACE |
3928a8a2 | 841 | struct ring_buffer_event *event; |
777e208d | 842 | struct stack_entry *entry; |
86387f7e | 843 | struct stack_trace trace; |
3928a8a2 | 844 | unsigned long irq_flags; |
86387f7e | 845 | |
3928a8a2 SR |
846 | event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), |
847 | &irq_flags); | |
848 | if (!event) | |
849 | return; | |
850 | entry = ring_buffer_event_data(event); | |
38697053 | 851 | tracing_generic_entry_update(&entry->ent, flags, pc); |
777e208d | 852 | entry->ent.type = TRACE_STACK; |
86387f7e | 853 | |
777e208d | 854 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
855 | |
856 | trace.nr_entries = 0; | |
857 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
858 | trace.skip = skip; | |
777e208d | 859 | trace.entries = entry->caller; |
86387f7e IM |
860 | |
861 | save_stack_trace(&trace); | |
3928a8a2 | 862 | ring_buffer_unlock_commit(tr->buffer, event, irq_flags); |
c2c80529 | 863 | #endif |
f0a920d5 IM |
864 | } |
865 | ||
53614991 SR |
866 | static void ftrace_trace_stack(struct trace_array *tr, |
867 | struct trace_array_cpu *data, | |
868 | unsigned long flags, | |
869 | int skip, int pc) | |
870 | { | |
871 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
872 | return; | |
873 | ||
874 | __ftrace_trace_stack(tr, data, flags, skip, pc); | |
875 | } | |
876 | ||
38697053 SR |
877 | void __trace_stack(struct trace_array *tr, |
878 | struct trace_array_cpu *data, | |
879 | unsigned long flags, | |
53614991 | 880 | int skip, int pc) |
38697053 | 881 | { |
53614991 | 882 | __ftrace_trace_stack(tr, data, flags, skip, pc); |
38697053 SR |
883 | } |
884 | ||
02b67518 TE |
885 | static void ftrace_trace_userstack(struct trace_array *tr, |
886 | struct trace_array_cpu *data, | |
887 | unsigned long flags, int pc) | |
888 | { | |
c7425acb | 889 | #ifdef CONFIG_STACKTRACE |
8d7c6a96 | 890 | struct ring_buffer_event *event; |
02b67518 TE |
891 | struct userstack_entry *entry; |
892 | struct stack_trace trace; | |
02b67518 TE |
893 | unsigned long irq_flags; |
894 | ||
895 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
896 | return; | |
897 | ||
898 | event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), | |
899 | &irq_flags); | |
900 | if (!event) | |
901 | return; | |
902 | entry = ring_buffer_event_data(event); | |
903 | tracing_generic_entry_update(&entry->ent, flags, pc); | |
904 | entry->ent.type = TRACE_USER_STACK; | |
905 | ||
906 | memset(&entry->caller, 0, sizeof(entry->caller)); | |
907 | ||
908 | trace.nr_entries = 0; | |
909 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
910 | trace.skip = 0; | |
911 | trace.entries = entry->caller; | |
912 | ||
913 | save_stack_trace_user(&trace); | |
914 | ring_buffer_unlock_commit(tr->buffer, event, irq_flags); | |
c7425acb | 915 | #endif |
02b67518 TE |
916 | } |
917 | ||
918 | void __trace_userstack(struct trace_array *tr, | |
919 | struct trace_array_cpu *data, | |
920 | unsigned long flags) | |
921 | { | |
922 | ftrace_trace_userstack(tr, data, flags, preempt_count()); | |
923 | } | |
924 | ||
38697053 SR |
925 | static void |
926 | ftrace_trace_special(void *__tr, void *__data, | |
927 | unsigned long arg1, unsigned long arg2, unsigned long arg3, | |
928 | int pc) | |
a4feb834 | 929 | { |
3928a8a2 | 930 | struct ring_buffer_event *event; |
a4feb834 IM |
931 | struct trace_array_cpu *data = __data; |
932 | struct trace_array *tr = __tr; | |
777e208d | 933 | struct special_entry *entry; |
a4feb834 IM |
934 | unsigned long irq_flags; |
935 | ||
3928a8a2 SR |
936 | event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), |
937 | &irq_flags); | |
938 | if (!event) | |
939 | return; | |
940 | entry = ring_buffer_event_data(event); | |
38697053 | 941 | tracing_generic_entry_update(&entry->ent, 0, pc); |
777e208d SR |
942 | entry->ent.type = TRACE_SPECIAL; |
943 | entry->arg1 = arg1; | |
944 | entry->arg2 = arg2; | |
945 | entry->arg3 = arg3; | |
3928a8a2 | 946 | ring_buffer_unlock_commit(tr->buffer, event, irq_flags); |
38697053 | 947 | ftrace_trace_stack(tr, data, irq_flags, 4, pc); |
02b67518 | 948 | ftrace_trace_userstack(tr, data, irq_flags, pc); |
a4feb834 IM |
949 | |
950 | trace_wake_up(); | |
951 | } | |
952 | ||
38697053 SR |
953 | void |
954 | __trace_special(void *__tr, void *__data, | |
955 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
956 | { | |
957 | ftrace_trace_special(__tr, __data, arg1, arg2, arg3, preempt_count()); | |
958 | } | |
959 | ||
e309b41d | 960 | void |
bc0c38d1 SR |
961 | tracing_sched_switch_trace(struct trace_array *tr, |
962 | struct trace_array_cpu *data, | |
86387f7e IM |
963 | struct task_struct *prev, |
964 | struct task_struct *next, | |
38697053 | 965 | unsigned long flags, int pc) |
bc0c38d1 | 966 | { |
3928a8a2 | 967 | struct ring_buffer_event *event; |
777e208d | 968 | struct ctx_switch_entry *entry; |
dcb6308f | 969 | unsigned long irq_flags; |
bc0c38d1 | 970 | |
3928a8a2 SR |
971 | event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), |
972 | &irq_flags); | |
973 | if (!event) | |
974 | return; | |
975 | entry = ring_buffer_event_data(event); | |
38697053 | 976 | tracing_generic_entry_update(&entry->ent, flags, pc); |
777e208d SR |
977 | entry->ent.type = TRACE_CTX; |
978 | entry->prev_pid = prev->pid; | |
979 | entry->prev_prio = prev->prio; | |
980 | entry->prev_state = prev->state; | |
981 | entry->next_pid = next->pid; | |
982 | entry->next_prio = next->prio; | |
983 | entry->next_state = next->state; | |
984 | entry->next_cpu = task_cpu(next); | |
3928a8a2 | 985 | ring_buffer_unlock_commit(tr->buffer, event, irq_flags); |
38697053 | 986 | ftrace_trace_stack(tr, data, flags, 5, pc); |
02b67518 | 987 | ftrace_trace_userstack(tr, data, flags, pc); |
bc0c38d1 SR |
988 | } |
989 | ||
57422797 IM |
990 | void |
991 | tracing_sched_wakeup_trace(struct trace_array *tr, | |
992 | struct trace_array_cpu *data, | |
86387f7e IM |
993 | struct task_struct *wakee, |
994 | struct task_struct *curr, | |
38697053 | 995 | unsigned long flags, int pc) |
57422797 | 996 | { |
3928a8a2 | 997 | struct ring_buffer_event *event; |
777e208d | 998 | struct ctx_switch_entry *entry; |
57422797 IM |
999 | unsigned long irq_flags; |
1000 | ||
3928a8a2 SR |
1001 | event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry), |
1002 | &irq_flags); | |
1003 | if (!event) | |
1004 | return; | |
1005 | entry = ring_buffer_event_data(event); | |
38697053 | 1006 | tracing_generic_entry_update(&entry->ent, flags, pc); |
777e208d SR |
1007 | entry->ent.type = TRACE_WAKE; |
1008 | entry->prev_pid = curr->pid; | |
1009 | entry->prev_prio = curr->prio; | |
1010 | entry->prev_state = curr->state; | |
1011 | entry->next_pid = wakee->pid; | |
1012 | entry->next_prio = wakee->prio; | |
1013 | entry->next_state = wakee->state; | |
1014 | entry->next_cpu = task_cpu(wakee); | |
3928a8a2 | 1015 | ring_buffer_unlock_commit(tr->buffer, event, irq_flags); |
38697053 | 1016 | ftrace_trace_stack(tr, data, flags, 6, pc); |
02b67518 | 1017 | ftrace_trace_userstack(tr, data, flags, pc); |
017730c1 IM |
1018 | |
1019 | trace_wake_up(); | |
57422797 IM |
1020 | } |
1021 | ||
4902f884 SR |
1022 | void |
1023 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1024 | { | |
1025 | struct trace_array *tr = &global_trace; | |
1026 | struct trace_array_cpu *data; | |
5aa1ba6a | 1027 | unsigned long flags; |
4902f884 | 1028 | int cpu; |
38697053 | 1029 | int pc; |
4902f884 | 1030 | |
c76f0694 | 1031 | if (tracing_disabled) |
4902f884 SR |
1032 | return; |
1033 | ||
38697053 | 1034 | pc = preempt_count(); |
5aa1ba6a | 1035 | local_irq_save(flags); |
4902f884 SR |
1036 | cpu = raw_smp_processor_id(); |
1037 | data = tr->data[cpu]; | |
4902f884 | 1038 | |
5aa1ba6a | 1039 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
38697053 | 1040 | ftrace_trace_special(tr, data, arg1, arg2, arg3, pc); |
4902f884 | 1041 | |
5aa1ba6a SR |
1042 | atomic_dec(&data->disabled); |
1043 | local_irq_restore(flags); | |
4902f884 SR |
1044 | } |
1045 | ||
fb52607a | 1046 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e49dc19c | 1047 | int trace_graph_entry(struct ftrace_graph_ent *trace) |
15e6cb36 FW |
1048 | { |
1049 | struct trace_array *tr = &global_trace; | |
1050 | struct trace_array_cpu *data; | |
1051 | unsigned long flags; | |
1052 | long disabled; | |
1053 | int cpu; | |
1054 | int pc; | |
1055 | ||
804a6851 SR |
1056 | if (!ftrace_trace_task(current)) |
1057 | return 0; | |
1058 | ||
ea4e2bc4 SR |
1059 | if (!ftrace_graph_addr(trace->func)) |
1060 | return 0; | |
1061 | ||
a5e25883 | 1062 | local_irq_save(flags); |
15e6cb36 FW |
1063 | cpu = raw_smp_processor_id(); |
1064 | data = tr->data[cpu]; | |
1065 | disabled = atomic_inc_return(&data->disabled); | |
1066 | if (likely(disabled == 1)) { | |
1067 | pc = preempt_count(); | |
287b6e68 FW |
1068 | __trace_graph_entry(tr, data, trace, flags, pc); |
1069 | } | |
ea4e2bc4 SR |
1070 | /* Only do the atomic if it is not already set */ |
1071 | if (!test_tsk_trace_graph(current)) | |
1072 | set_tsk_trace_graph(current); | |
287b6e68 | 1073 | atomic_dec(&data->disabled); |
a5e25883 | 1074 | local_irq_restore(flags); |
e49dc19c SR |
1075 | |
1076 | return 1; | |
287b6e68 FW |
1077 | } |
1078 | ||
1079 | void trace_graph_return(struct ftrace_graph_ret *trace) | |
1080 | { | |
1081 | struct trace_array *tr = &global_trace; | |
1082 | struct trace_array_cpu *data; | |
1083 | unsigned long flags; | |
1084 | long disabled; | |
1085 | int cpu; | |
1086 | int pc; | |
1087 | ||
a5e25883 | 1088 | local_irq_save(flags); |
287b6e68 FW |
1089 | cpu = raw_smp_processor_id(); |
1090 | data = tr->data[cpu]; | |
1091 | disabled = atomic_inc_return(&data->disabled); | |
1092 | if (likely(disabled == 1)) { | |
1093 | pc = preempt_count(); | |
1094 | __trace_graph_return(tr, data, trace, flags, pc); | |
15e6cb36 | 1095 | } |
ea4e2bc4 SR |
1096 | if (!trace->depth) |
1097 | clear_tsk_trace_graph(current); | |
15e6cb36 | 1098 | atomic_dec(&data->disabled); |
a5e25883 | 1099 | local_irq_restore(flags); |
15e6cb36 | 1100 | } |
fb52607a | 1101 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
15e6cb36 | 1102 | |
bc0c38d1 SR |
1103 | enum trace_file_type { |
1104 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1105 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1106 | }; |
1107 | ||
e2ac8ef5 | 1108 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1109 | { |
d769041f SR |
1110 | /* Don't allow ftrace to trace into the ring buffers */ |
1111 | ftrace_disable_cpu(); | |
1112 | ||
5a90f577 | 1113 | iter->idx++; |
d769041f SR |
1114 | if (iter->buffer_iter[iter->cpu]) |
1115 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1116 | ||
1117 | ftrace_enable_cpu(); | |
5a90f577 SR |
1118 | } |
1119 | ||
e309b41d | 1120 | static struct trace_entry * |
3928a8a2 | 1121 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1122 | { |
3928a8a2 SR |
1123 | struct ring_buffer_event *event; |
1124 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1125 | |
d769041f SR |
1126 | /* Don't allow ftrace to trace into the ring buffers */ |
1127 | ftrace_disable_cpu(); | |
1128 | ||
1129 | if (buf_iter) | |
1130 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1131 | else | |
1132 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1133 | ||
1134 | ftrace_enable_cpu(); | |
1135 | ||
3928a8a2 | 1136 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1137 | } |
d769041f | 1138 | |
dd0e545f | 1139 | static struct trace_entry * |
3928a8a2 | 1140 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1141 | { |
3928a8a2 | 1142 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1143 | struct trace_entry *ent, *next = NULL; |
3928a8a2 | 1144 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1145 | int next_cpu = -1; |
1146 | int cpu; | |
1147 | ||
ab46428c | 1148 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1149 | |
3928a8a2 SR |
1150 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1151 | continue; | |
dd0e545f | 1152 | |
3928a8a2 | 1153 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1154 | |
cdd31cd2 IM |
1155 | /* |
1156 | * Pick the entry with the smallest timestamp: | |
1157 | */ | |
3928a8a2 | 1158 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1159 | next = ent; |
1160 | next_cpu = cpu; | |
3928a8a2 | 1161 | next_ts = ts; |
bc0c38d1 SR |
1162 | } |
1163 | } | |
1164 | ||
1165 | if (ent_cpu) | |
1166 | *ent_cpu = next_cpu; | |
1167 | ||
3928a8a2 SR |
1168 | if (ent_ts) |
1169 | *ent_ts = next_ts; | |
1170 | ||
bc0c38d1 SR |
1171 | return next; |
1172 | } | |
1173 | ||
dd0e545f | 1174 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1175 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1176 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1177 | { |
3928a8a2 | 1178 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1179 | } |
1180 | ||
1181 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1182 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1183 | { | |
3928a8a2 | 1184 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1185 | |
3928a8a2 | 1186 | if (iter->ent) |
e2ac8ef5 | 1187 | trace_iterator_increment(iter); |
dd0e545f | 1188 | |
3928a8a2 | 1189 | return iter->ent ? iter : NULL; |
b3806b43 | 1190 | } |
bc0c38d1 | 1191 | |
e309b41d | 1192 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1193 | { |
d769041f SR |
1194 | /* Don't allow ftrace to trace into the ring buffers */ |
1195 | ftrace_disable_cpu(); | |
3928a8a2 | 1196 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1197 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1198 | } |
1199 | ||
e309b41d | 1200 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1201 | { |
1202 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1203 | int i = (int)*pos; |
4e3c3333 | 1204 | void *ent; |
bc0c38d1 SR |
1205 | |
1206 | (*pos)++; | |
1207 | ||
1208 | /* can't go backwards */ | |
1209 | if (iter->idx > i) | |
1210 | return NULL; | |
1211 | ||
1212 | if (iter->idx < 0) | |
1213 | ent = find_next_entry_inc(iter); | |
1214 | else | |
1215 | ent = iter; | |
1216 | ||
1217 | while (ent && iter->idx < i) | |
1218 | ent = find_next_entry_inc(iter); | |
1219 | ||
1220 | iter->pos = *pos; | |
1221 | ||
bc0c38d1 SR |
1222 | return ent; |
1223 | } | |
1224 | ||
1225 | static void *s_start(struct seq_file *m, loff_t *pos) | |
1226 | { | |
1227 | struct trace_iterator *iter = m->private; | |
1228 | void *p = NULL; | |
1229 | loff_t l = 0; | |
3928a8a2 | 1230 | int cpu; |
bc0c38d1 SR |
1231 | |
1232 | mutex_lock(&trace_types_lock); | |
1233 | ||
d15f57f2 SR |
1234 | if (!current_trace || current_trace != iter->trace) { |
1235 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 1236 | return NULL; |
d15f57f2 | 1237 | } |
bc0c38d1 SR |
1238 | |
1239 | atomic_inc(&trace_record_cmdline_disabled); | |
1240 | ||
bc0c38d1 SR |
1241 | if (*pos != iter->pos) { |
1242 | iter->ent = NULL; | |
1243 | iter->cpu = 0; | |
1244 | iter->idx = -1; | |
1245 | ||
d769041f SR |
1246 | ftrace_disable_cpu(); |
1247 | ||
3928a8a2 SR |
1248 | for_each_tracing_cpu(cpu) { |
1249 | ring_buffer_iter_reset(iter->buffer_iter[cpu]); | |
4c11d7ae | 1250 | } |
bc0c38d1 | 1251 | |
d769041f SR |
1252 | ftrace_enable_cpu(); |
1253 | ||
bc0c38d1 SR |
1254 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1255 | ; | |
1256 | ||
1257 | } else { | |
4c11d7ae | 1258 | l = *pos - 1; |
bc0c38d1 SR |
1259 | p = s_next(m, p, &l); |
1260 | } | |
1261 | ||
1262 | return p; | |
1263 | } | |
1264 | ||
1265 | static void s_stop(struct seq_file *m, void *p) | |
1266 | { | |
bc0c38d1 | 1267 | atomic_dec(&trace_record_cmdline_disabled); |
bc0c38d1 SR |
1268 | mutex_unlock(&trace_types_lock); |
1269 | } | |
1270 | ||
e309b41d | 1271 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1272 | { |
a6168353 ME |
1273 | seq_puts(m, "# _------=> CPU# \n"); |
1274 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1275 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1276 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1277 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1278 | seq_puts(m, "# |||| / \n"); | |
1279 | seq_puts(m, "# ||||| delay \n"); | |
1280 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1281 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1282 | } |
1283 | ||
e309b41d | 1284 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1285 | { |
a6168353 ME |
1286 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1287 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1288 | } |
1289 | ||
1290 | ||
e309b41d | 1291 | static void |
bc0c38d1 SR |
1292 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1293 | { | |
1294 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1295 | struct trace_array *tr = iter->tr; | |
1296 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1297 | struct tracer *type = current_trace; | |
3928a8a2 SR |
1298 | unsigned long total; |
1299 | unsigned long entries; | |
bc0c38d1 SR |
1300 | const char *name = "preemption"; |
1301 | ||
1302 | if (type) | |
1303 | name = type->name; | |
1304 | ||
3928a8a2 SR |
1305 | entries = ring_buffer_entries(iter->tr->buffer); |
1306 | total = entries + | |
1307 | ring_buffer_overruns(iter->tr->buffer); | |
bc0c38d1 SR |
1308 | |
1309 | seq_printf(m, "%s latency trace v1.1.5 on %s\n", | |
1310 | name, UTS_RELEASE); | |
1311 | seq_puts(m, "-----------------------------------" | |
1312 | "---------------------------------\n"); | |
1313 | seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |" | |
1314 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", | |
57f50be1 | 1315 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1316 | entries, |
4c11d7ae | 1317 | total, |
bc0c38d1 SR |
1318 | tr->cpu, |
1319 | #if defined(CONFIG_PREEMPT_NONE) | |
1320 | "server", | |
1321 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1322 | "desktop", | |
b5c21b45 | 1323 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1324 | "preempt", |
1325 | #else | |
1326 | "unknown", | |
1327 | #endif | |
1328 | /* These are reserved for later use */ | |
1329 | 0, 0, 0, 0); | |
1330 | #ifdef CONFIG_SMP | |
1331 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1332 | #else | |
1333 | seq_puts(m, ")\n"); | |
1334 | #endif | |
1335 | seq_puts(m, " -----------------\n"); | |
1336 | seq_printf(m, " | task: %.16s-%d " | |
1337 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", | |
1338 | data->comm, data->pid, data->uid, data->nice, | |
1339 | data->policy, data->rt_priority); | |
1340 | seq_puts(m, " -----------------\n"); | |
1341 | ||
1342 | if (data->critical_start) { | |
1343 | seq_puts(m, " => started at: "); | |
214023c3 SR |
1344 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1345 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 | 1346 | seq_puts(m, "\n => ended at: "); |
214023c3 SR |
1347 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1348 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 SR |
1349 | seq_puts(m, "\n"); |
1350 | } | |
1351 | ||
1352 | seq_puts(m, "\n"); | |
1353 | } | |
1354 | ||
a309720c SR |
1355 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1356 | { | |
1357 | struct trace_seq *s = &iter->seq; | |
1358 | ||
12ef7d44 SR |
1359 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1360 | return; | |
1361 | ||
1362 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1363 | return; | |
1364 | ||
4462344e | 1365 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1366 | return; |
1367 | ||
4462344e | 1368 | cpumask_set_cpu(iter->cpu, iter->started); |
a309720c SR |
1369 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", iter->cpu); |
1370 | } | |
1371 | ||
c4a8e8be | 1372 | static enum print_line_t print_lat_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1373 | { |
214023c3 | 1374 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1375 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
f633cef0 | 1376 | struct trace_event *event; |
bc0c38d1 | 1377 | struct trace_entry *entry = iter->ent; |
f633cef0 | 1378 | int ret; |
dd0e545f | 1379 | |
a309720c SR |
1380 | test_cpu_buff_start(iter); |
1381 | ||
c4a8e8be FW |
1382 | event = ftrace_find_event(entry->type); |
1383 | ||
1384 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { | |
1385 | ret = trace_print_lat_context(iter); | |
1386 | if (ret) | |
1387 | return ret; | |
bc0c38d1 | 1388 | } |
777e208d | 1389 | |
f633cef0 SR |
1390 | if (event && event->latency_trace) { |
1391 | ret = event->latency_trace(s, entry, sym_flags); | |
1392 | if (ret) | |
1393 | return ret; | |
1394 | return TRACE_TYPE_HANDLED; | |
52f232cb | 1395 | } |
02b67518 | 1396 | |
f633cef0 | 1397 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
2c4f035f | 1398 | return TRACE_TYPE_HANDLED; |
bc0c38d1 SR |
1399 | } |
1400 | ||
2c4f035f | 1401 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1402 | { |
214023c3 | 1403 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1404 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1405 | struct trace_entry *entry; |
f633cef0 | 1406 | struct trace_event *event; |
b3806b43 | 1407 | int ret; |
bc0c38d1 | 1408 | |
4e3c3333 | 1409 | entry = iter->ent; |
dd0e545f | 1410 | |
a309720c SR |
1411 | test_cpu_buff_start(iter); |
1412 | ||
c4a8e8be | 1413 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1414 | |
c4a8e8be FW |
1415 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1416 | ret = trace_print_context(iter); | |
1417 | if (ret) | |
1418 | return ret; | |
1419 | } | |
bc0c38d1 | 1420 | |
f633cef0 SR |
1421 | if (event && event->trace) { |
1422 | ret = event->trace(s, entry, sym_flags); | |
1423 | if (ret) | |
1424 | return ret; | |
1425 | return TRACE_TYPE_HANDLED; | |
52f232cb | 1426 | } |
f633cef0 SR |
1427 | ret = trace_seq_printf(s, "Unknown type %d\n", entry->type); |
1428 | if (!ret) | |
1429 | return TRACE_TYPE_PARTIAL_LINE; | |
02b67518 | 1430 | |
2c4f035f | 1431 | return TRACE_TYPE_HANDLED; |
bc0c38d1 SR |
1432 | } |
1433 | ||
2c4f035f | 1434 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1435 | { |
1436 | struct trace_seq *s = &iter->seq; | |
1437 | struct trace_entry *entry; | |
f633cef0 | 1438 | struct trace_event *event; |
f9896bf3 | 1439 | int ret; |
f9896bf3 IM |
1440 | |
1441 | entry = iter->ent; | |
dd0e545f | 1442 | |
c4a8e8be FW |
1443 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1444 | ret = trace_seq_printf(s, "%d %d %llu ", | |
1445 | entry->pid, iter->cpu, iter->ts); | |
1446 | if (!ret) | |
1447 | return TRACE_TYPE_PARTIAL_LINE; | |
1448 | } | |
f9896bf3 | 1449 | |
f633cef0 SR |
1450 | event = ftrace_find_event(entry->type); |
1451 | if (event && event->raw) { | |
1452 | ret = event->raw(s, entry, 0); | |
1453 | if (ret) | |
1454 | return ret; | |
1455 | return TRACE_TYPE_HANDLED; | |
777e208d | 1456 | } |
f633cef0 SR |
1457 | ret = trace_seq_printf(s, "%d ?\n", entry->type); |
1458 | if (!ret) | |
1459 | return TRACE_TYPE_PARTIAL_LINE; | |
777e208d | 1460 | |
2c4f035f | 1461 | return TRACE_TYPE_HANDLED; |
f9896bf3 IM |
1462 | } |
1463 | ||
2c4f035f | 1464 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1465 | { |
1466 | struct trace_seq *s = &iter->seq; | |
1467 | unsigned char newline = '\n'; | |
1468 | struct trace_entry *entry; | |
f633cef0 | 1469 | struct trace_event *event; |
5e3ca0ec IM |
1470 | |
1471 | entry = iter->ent; | |
dd0e545f | 1472 | |
c4a8e8be FW |
1473 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1474 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1475 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1476 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1477 | } | |
5e3ca0ec | 1478 | |
f633cef0 SR |
1479 | event = ftrace_find_event(entry->type); |
1480 | if (event && event->hex) | |
1481 | event->hex(s, entry, 0); | |
7104f300 | 1482 | |
5e3ca0ec IM |
1483 | SEQ_PUT_FIELD_RET(s, newline); |
1484 | ||
2c4f035f | 1485 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1486 | } |
1487 | ||
66896a85 FW |
1488 | static enum print_line_t print_printk_msg_only(struct trace_iterator *iter) |
1489 | { | |
1490 | struct trace_seq *s = &iter->seq; | |
1491 | struct trace_entry *entry = iter->ent; | |
1492 | struct print_entry *field; | |
1493 | int ret; | |
1494 | ||
1495 | trace_assign_type(field, entry); | |
1496 | ||
c4a8e8be | 1497 | ret = trace_seq_printf(s, "%s", field->buf); |
66896a85 FW |
1498 | if (!ret) |
1499 | return TRACE_TYPE_PARTIAL_LINE; | |
1500 | ||
66896a85 FW |
1501 | return TRACE_TYPE_HANDLED; |
1502 | } | |
1503 | ||
2c4f035f | 1504 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1505 | { |
1506 | struct trace_seq *s = &iter->seq; | |
1507 | struct trace_entry *entry; | |
f633cef0 | 1508 | struct trace_event *event; |
cb0f12aa IM |
1509 | |
1510 | entry = iter->ent; | |
dd0e545f | 1511 | |
c4a8e8be FW |
1512 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1513 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1514 | SEQ_PUT_FIELD_RET(s, entry->cpu); | |
1515 | SEQ_PUT_FIELD_RET(s, iter->ts); | |
1516 | } | |
cb0f12aa | 1517 | |
f633cef0 SR |
1518 | event = ftrace_find_event(entry->type); |
1519 | if (event && event->binary) | |
1520 | event->binary(s, entry, 0); | |
777e208d | 1521 | |
f633cef0 | 1522 | return TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1523 | } |
1524 | ||
bc0c38d1 SR |
1525 | static int trace_empty(struct trace_iterator *iter) |
1526 | { | |
bc0c38d1 SR |
1527 | int cpu; |
1528 | ||
ab46428c | 1529 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1530 | if (iter->buffer_iter[cpu]) { |
1531 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1532 | return 0; | |
1533 | } else { | |
1534 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1535 | return 0; | |
1536 | } | |
bc0c38d1 | 1537 | } |
d769041f | 1538 | |
797d3712 | 1539 | return 1; |
bc0c38d1 SR |
1540 | } |
1541 | ||
2c4f035f | 1542 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1543 | { |
2c4f035f FW |
1544 | enum print_line_t ret; |
1545 | ||
1546 | if (iter->trace && iter->trace->print_line) { | |
1547 | ret = iter->trace->print_line(iter); | |
1548 | if (ret != TRACE_TYPE_UNHANDLED) | |
1549 | return ret; | |
1550 | } | |
72829bc3 | 1551 | |
66896a85 FW |
1552 | if (iter->ent->type == TRACE_PRINT && |
1553 | trace_flags & TRACE_ITER_PRINTK && | |
1554 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
1555 | return print_printk_msg_only(iter); | |
1556 | ||
cb0f12aa IM |
1557 | if (trace_flags & TRACE_ITER_BIN) |
1558 | return print_bin_fmt(iter); | |
1559 | ||
5e3ca0ec IM |
1560 | if (trace_flags & TRACE_ITER_HEX) |
1561 | return print_hex_fmt(iter); | |
1562 | ||
f9896bf3 IM |
1563 | if (trace_flags & TRACE_ITER_RAW) |
1564 | return print_raw_fmt(iter); | |
1565 | ||
1566 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
c4a8e8be | 1567 | return print_lat_fmt(iter); |
f9896bf3 IM |
1568 | |
1569 | return print_trace_fmt(iter); | |
1570 | } | |
1571 | ||
bc0c38d1 SR |
1572 | static int s_show(struct seq_file *m, void *v) |
1573 | { | |
1574 | struct trace_iterator *iter = v; | |
1575 | ||
1576 | if (iter->ent == NULL) { | |
1577 | if (iter->tr) { | |
1578 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1579 | seq_puts(m, "#\n"); | |
1580 | } | |
8bba1bf5 MM |
1581 | if (iter->trace && iter->trace->print_header) |
1582 | iter->trace->print_header(m); | |
1583 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
1584 | /* print nothing if the buffers are empty */ |
1585 | if (trace_empty(iter)) | |
1586 | return 0; | |
1587 | print_trace_header(m, iter); | |
1588 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1589 | print_lat_help_header(m); | |
1590 | } else { | |
1591 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1592 | print_func_help_header(m); | |
1593 | } | |
1594 | } else { | |
f9896bf3 | 1595 | print_trace_line(iter); |
214023c3 | 1596 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1597 | } |
1598 | ||
1599 | return 0; | |
1600 | } | |
1601 | ||
1602 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1603 | .start = s_start, |
1604 | .next = s_next, | |
1605 | .stop = s_stop, | |
1606 | .show = s_show, | |
bc0c38d1 SR |
1607 | }; |
1608 | ||
e309b41d | 1609 | static struct trace_iterator * |
bc0c38d1 SR |
1610 | __tracing_open(struct inode *inode, struct file *file, int *ret) |
1611 | { | |
1612 | struct trace_iterator *iter; | |
3928a8a2 SR |
1613 | struct seq_file *m; |
1614 | int cpu; | |
bc0c38d1 | 1615 | |
60a11774 SR |
1616 | if (tracing_disabled) { |
1617 | *ret = -ENODEV; | |
1618 | return NULL; | |
1619 | } | |
1620 | ||
bc0c38d1 SR |
1621 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
1622 | if (!iter) { | |
1623 | *ret = -ENOMEM; | |
1624 | goto out; | |
1625 | } | |
1626 | ||
1627 | mutex_lock(&trace_types_lock); | |
1628 | if (current_trace && current_trace->print_max) | |
1629 | iter->tr = &max_tr; | |
1630 | else | |
1631 | iter->tr = inode->i_private; | |
1632 | iter->trace = current_trace; | |
1633 | iter->pos = -1; | |
1634 | ||
8bba1bf5 MM |
1635 | /* Notify the tracer early; before we stop tracing. */ |
1636 | if (iter->trace && iter->trace->open) | |
a93751ca | 1637 | iter->trace->open(iter); |
8bba1bf5 | 1638 | |
12ef7d44 SR |
1639 | /* Annotate start of buffers if we had overruns */ |
1640 | if (ring_buffer_overruns(iter->tr->buffer)) | |
1641 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
1642 | ||
1643 | ||
3928a8a2 | 1644 | for_each_tracing_cpu(cpu) { |
d769041f | 1645 | |
3928a8a2 SR |
1646 | iter->buffer_iter[cpu] = |
1647 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
d769041f | 1648 | |
3928a8a2 SR |
1649 | if (!iter->buffer_iter[cpu]) |
1650 | goto fail_buffer; | |
1651 | } | |
1652 | ||
bc0c38d1 SR |
1653 | /* TODO stop tracer */ |
1654 | *ret = seq_open(file, &tracer_seq_ops); | |
3928a8a2 SR |
1655 | if (*ret) |
1656 | goto fail_buffer; | |
bc0c38d1 | 1657 | |
3928a8a2 SR |
1658 | m = file->private_data; |
1659 | m->private = iter; | |
bc0c38d1 | 1660 | |
3928a8a2 | 1661 | /* stop the trace while dumping */ |
9036990d | 1662 | tracing_stop(); |
3928a8a2 | 1663 | |
bc0c38d1 SR |
1664 | mutex_unlock(&trace_types_lock); |
1665 | ||
1666 | out: | |
1667 | return iter; | |
3928a8a2 SR |
1668 | |
1669 | fail_buffer: | |
1670 | for_each_tracing_cpu(cpu) { | |
1671 | if (iter->buffer_iter[cpu]) | |
1672 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1673 | } | |
1674 | mutex_unlock(&trace_types_lock); | |
0bb943c7 | 1675 | kfree(iter); |
3928a8a2 SR |
1676 | |
1677 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
1678 | } |
1679 | ||
1680 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1681 | { | |
60a11774 SR |
1682 | if (tracing_disabled) |
1683 | return -ENODEV; | |
1684 | ||
bc0c38d1 SR |
1685 | filp->private_data = inode->i_private; |
1686 | return 0; | |
1687 | } | |
1688 | ||
1689 | int tracing_release(struct inode *inode, struct file *file) | |
1690 | { | |
1691 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1692 | struct trace_iterator *iter = m->private; | |
3928a8a2 | 1693 | int cpu; |
bc0c38d1 SR |
1694 | |
1695 | mutex_lock(&trace_types_lock); | |
3928a8a2 SR |
1696 | for_each_tracing_cpu(cpu) { |
1697 | if (iter->buffer_iter[cpu]) | |
1698 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1699 | } | |
1700 | ||
bc0c38d1 SR |
1701 | if (iter->trace && iter->trace->close) |
1702 | iter->trace->close(iter); | |
1703 | ||
1704 | /* reenable tracing if it was previously enabled */ | |
9036990d | 1705 | tracing_start(); |
bc0c38d1 SR |
1706 | mutex_unlock(&trace_types_lock); |
1707 | ||
1708 | seq_release(inode, file); | |
1709 | kfree(iter); | |
1710 | return 0; | |
1711 | } | |
1712 | ||
1713 | static int tracing_open(struct inode *inode, struct file *file) | |
1714 | { | |
1715 | int ret; | |
1716 | ||
1717 | __tracing_open(inode, file, &ret); | |
1718 | ||
1719 | return ret; | |
1720 | } | |
1721 | ||
1722 | static int tracing_lt_open(struct inode *inode, struct file *file) | |
1723 | { | |
1724 | struct trace_iterator *iter; | |
1725 | int ret; | |
1726 | ||
1727 | iter = __tracing_open(inode, file, &ret); | |
1728 | ||
1729 | if (!ret) | |
1730 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
1731 | ||
1732 | return ret; | |
1733 | } | |
1734 | ||
1735 | ||
e309b41d | 1736 | static void * |
bc0c38d1 SR |
1737 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1738 | { | |
1739 | struct tracer *t = m->private; | |
1740 | ||
1741 | (*pos)++; | |
1742 | ||
1743 | if (t) | |
1744 | t = t->next; | |
1745 | ||
1746 | m->private = t; | |
1747 | ||
1748 | return t; | |
1749 | } | |
1750 | ||
1751 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1752 | { | |
1753 | struct tracer *t = m->private; | |
1754 | loff_t l = 0; | |
1755 | ||
1756 | mutex_lock(&trace_types_lock); | |
1757 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
1758 | ; | |
1759 | ||
1760 | return t; | |
1761 | } | |
1762 | ||
1763 | static void t_stop(struct seq_file *m, void *p) | |
1764 | { | |
1765 | mutex_unlock(&trace_types_lock); | |
1766 | } | |
1767 | ||
1768 | static int t_show(struct seq_file *m, void *v) | |
1769 | { | |
1770 | struct tracer *t = v; | |
1771 | ||
1772 | if (!t) | |
1773 | return 0; | |
1774 | ||
1775 | seq_printf(m, "%s", t->name); | |
1776 | if (t->next) | |
1777 | seq_putc(m, ' '); | |
1778 | else | |
1779 | seq_putc(m, '\n'); | |
1780 | ||
1781 | return 0; | |
1782 | } | |
1783 | ||
1784 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
1785 | .start = t_start, |
1786 | .next = t_next, | |
1787 | .stop = t_stop, | |
1788 | .show = t_show, | |
bc0c38d1 SR |
1789 | }; |
1790 | ||
1791 | static int show_traces_open(struct inode *inode, struct file *file) | |
1792 | { | |
1793 | int ret; | |
1794 | ||
60a11774 SR |
1795 | if (tracing_disabled) |
1796 | return -ENODEV; | |
1797 | ||
bc0c38d1 SR |
1798 | ret = seq_open(file, &show_traces_seq_ops); |
1799 | if (!ret) { | |
1800 | struct seq_file *m = file->private_data; | |
1801 | m->private = trace_types; | |
1802 | } | |
1803 | ||
1804 | return ret; | |
1805 | } | |
1806 | ||
1807 | static struct file_operations tracing_fops = { | |
4bf39a94 IM |
1808 | .open = tracing_open, |
1809 | .read = seq_read, | |
1810 | .llseek = seq_lseek, | |
1811 | .release = tracing_release, | |
bc0c38d1 SR |
1812 | }; |
1813 | ||
1814 | static struct file_operations tracing_lt_fops = { | |
4bf39a94 IM |
1815 | .open = tracing_lt_open, |
1816 | .read = seq_read, | |
1817 | .llseek = seq_lseek, | |
1818 | .release = tracing_release, | |
bc0c38d1 SR |
1819 | }; |
1820 | ||
1821 | static struct file_operations show_traces_fops = { | |
c7078de1 IM |
1822 | .open = show_traces_open, |
1823 | .read = seq_read, | |
1824 | .release = seq_release, | |
1825 | }; | |
1826 | ||
36dfe925 IM |
1827 | /* |
1828 | * Only trace on a CPU if the bitmask is set: | |
1829 | */ | |
9e01c1b7 | 1830 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
1831 | |
1832 | /* | |
1833 | * The tracer itself will not take this lock, but still we want | |
1834 | * to provide a consistent cpumask to user-space: | |
1835 | */ | |
1836 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
1837 | ||
1838 | /* | |
1839 | * Temporary storage for the character representation of the | |
1840 | * CPU bitmask (and one more byte for the newline): | |
1841 | */ | |
1842 | static char mask_str[NR_CPUS + 1]; | |
1843 | ||
c7078de1 IM |
1844 | static ssize_t |
1845 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
1846 | size_t count, loff_t *ppos) | |
1847 | { | |
36dfe925 | 1848 | int len; |
c7078de1 IM |
1849 | |
1850 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 1851 | |
9e01c1b7 | 1852 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
1853 | if (count - len < 2) { |
1854 | count = -EINVAL; | |
1855 | goto out_err; | |
1856 | } | |
1857 | len += sprintf(mask_str + len, "\n"); | |
1858 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
1859 | ||
1860 | out_err: | |
c7078de1 IM |
1861 | mutex_unlock(&tracing_cpumask_update_lock); |
1862 | ||
1863 | return count; | |
1864 | } | |
1865 | ||
1866 | static ssize_t | |
1867 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
1868 | size_t count, loff_t *ppos) | |
1869 | { | |
36dfe925 | 1870 | int err, cpu; |
9e01c1b7 RR |
1871 | cpumask_var_t tracing_cpumask_new; |
1872 | ||
1873 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
1874 | return -ENOMEM; | |
c7078de1 IM |
1875 | |
1876 | mutex_lock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 1877 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 1878 | if (err) |
36dfe925 IM |
1879 | goto err_unlock; |
1880 | ||
a5e25883 | 1881 | local_irq_disable(); |
92205c23 | 1882 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 1883 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
1884 | /* |
1885 | * Increase/decrease the disabled counter if we are | |
1886 | * about to flip a bit in the cpumask: | |
1887 | */ | |
9e01c1b7 RR |
1888 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
1889 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
1890 | atomic_inc(&global_trace.data[cpu]->disabled); |
1891 | } | |
9e01c1b7 RR |
1892 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
1893 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
1894 | atomic_dec(&global_trace.data[cpu]->disabled); |
1895 | } | |
1896 | } | |
92205c23 | 1897 | __raw_spin_unlock(&ftrace_max_lock); |
a5e25883 | 1898 | local_irq_enable(); |
36dfe925 | 1899 | |
9e01c1b7 | 1900 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
1901 | |
1902 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 1903 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
1904 | |
1905 | return count; | |
36dfe925 IM |
1906 | |
1907 | err_unlock: | |
1908 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 1909 | free_cpumask_var(tracing_cpumask); |
36dfe925 IM |
1910 | |
1911 | return err; | |
c7078de1 IM |
1912 | } |
1913 | ||
1914 | static struct file_operations tracing_cpumask_fops = { | |
1915 | .open = tracing_open_generic, | |
1916 | .read = tracing_cpumask_read, | |
1917 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
1918 | }; |
1919 | ||
1920 | static ssize_t | |
ee6bce52 | 1921 | tracing_trace_options_read(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
1922 | size_t cnt, loff_t *ppos) |
1923 | { | |
adf9f195 | 1924 | int i; |
bc0c38d1 SR |
1925 | char *buf; |
1926 | int r = 0; | |
1927 | int len = 0; | |
adf9f195 FW |
1928 | u32 tracer_flags = current_trace->flags->val; |
1929 | struct tracer_opt *trace_opts = current_trace->flags->opts; | |
1930 | ||
bc0c38d1 SR |
1931 | |
1932 | /* calulate max size */ | |
1933 | for (i = 0; trace_options[i]; i++) { | |
1934 | len += strlen(trace_options[i]); | |
1935 | len += 3; /* "no" and space */ | |
1936 | } | |
1937 | ||
adf9f195 FW |
1938 | /* |
1939 | * Increase the size with names of options specific | |
1940 | * of the current tracer. | |
1941 | */ | |
1942 | for (i = 0; trace_opts[i].name; i++) { | |
1943 | len += strlen(trace_opts[i].name); | |
1944 | len += 3; /* "no" and space */ | |
1945 | } | |
1946 | ||
bc0c38d1 SR |
1947 | /* +2 for \n and \0 */ |
1948 | buf = kmalloc(len + 2, GFP_KERNEL); | |
1949 | if (!buf) | |
1950 | return -ENOMEM; | |
1951 | ||
1952 | for (i = 0; trace_options[i]; i++) { | |
1953 | if (trace_flags & (1 << i)) | |
1954 | r += sprintf(buf + r, "%s ", trace_options[i]); | |
1955 | else | |
1956 | r += sprintf(buf + r, "no%s ", trace_options[i]); | |
1957 | } | |
1958 | ||
adf9f195 FW |
1959 | for (i = 0; trace_opts[i].name; i++) { |
1960 | if (tracer_flags & trace_opts[i].bit) | |
1961 | r += sprintf(buf + r, "%s ", | |
1962 | trace_opts[i].name); | |
1963 | else | |
1964 | r += sprintf(buf + r, "no%s ", | |
1965 | trace_opts[i].name); | |
1966 | } | |
1967 | ||
bc0c38d1 SR |
1968 | r += sprintf(buf + r, "\n"); |
1969 | WARN_ON(r >= len + 2); | |
1970 | ||
36dfe925 | 1971 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
1972 | |
1973 | kfree(buf); | |
1974 | ||
1975 | return r; | |
1976 | } | |
1977 | ||
adf9f195 FW |
1978 | /* Try to assign a tracer specific option */ |
1979 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
1980 | { | |
1981 | struct tracer_flags *trace_flags = trace->flags; | |
1982 | struct tracer_opt *opts = NULL; | |
1983 | int ret = 0, i = 0; | |
1984 | int len; | |
1985 | ||
1986 | for (i = 0; trace_flags->opts[i].name; i++) { | |
1987 | opts = &trace_flags->opts[i]; | |
1988 | len = strlen(opts->name); | |
1989 | ||
1990 | if (strncmp(cmp, opts->name, len) == 0) { | |
1991 | ret = trace->set_flag(trace_flags->val, | |
1992 | opts->bit, !neg); | |
1993 | break; | |
1994 | } | |
1995 | } | |
1996 | /* Not found */ | |
1997 | if (!trace_flags->opts[i].name) | |
1998 | return -EINVAL; | |
1999 | ||
2000 | /* Refused to handle */ | |
2001 | if (ret) | |
2002 | return ret; | |
2003 | ||
2004 | if (neg) | |
2005 | trace_flags->val &= ~opts->bit; | |
2006 | else | |
2007 | trace_flags->val |= opts->bit; | |
2008 | ||
2009 | return 0; | |
2010 | } | |
2011 | ||
bc0c38d1 | 2012 | static ssize_t |
ee6bce52 | 2013 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2014 | size_t cnt, loff_t *ppos) |
2015 | { | |
2016 | char buf[64]; | |
2017 | char *cmp = buf; | |
2018 | int neg = 0; | |
adf9f195 | 2019 | int ret; |
bc0c38d1 SR |
2020 | int i; |
2021 | ||
cffae437 SR |
2022 | if (cnt >= sizeof(buf)) |
2023 | return -EINVAL; | |
bc0c38d1 SR |
2024 | |
2025 | if (copy_from_user(&buf, ubuf, cnt)) | |
2026 | return -EFAULT; | |
2027 | ||
2028 | buf[cnt] = 0; | |
2029 | ||
2030 | if (strncmp(buf, "no", 2) == 0) { | |
2031 | neg = 1; | |
2032 | cmp += 2; | |
2033 | } | |
2034 | ||
2035 | for (i = 0; trace_options[i]; i++) { | |
2036 | int len = strlen(trace_options[i]); | |
2037 | ||
2038 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
2039 | if (neg) | |
2040 | trace_flags &= ~(1 << i); | |
2041 | else | |
2042 | trace_flags |= (1 << i); | |
2043 | break; | |
2044 | } | |
2045 | } | |
adf9f195 FW |
2046 | |
2047 | /* If no option could be set, test the specific tracer options */ | |
2048 | if (!trace_options[i]) { | |
2049 | ret = set_tracer_option(current_trace, cmp, neg); | |
2050 | if (ret) | |
2051 | return ret; | |
2052 | } | |
bc0c38d1 SR |
2053 | |
2054 | filp->f_pos += cnt; | |
2055 | ||
2056 | return cnt; | |
2057 | } | |
2058 | ||
2059 | static struct file_operations tracing_iter_fops = { | |
c7078de1 | 2060 | .open = tracing_open_generic, |
ee6bce52 SR |
2061 | .read = tracing_trace_options_read, |
2062 | .write = tracing_trace_options_write, | |
bc0c38d1 SR |
2063 | }; |
2064 | ||
7bd2f24c IM |
2065 | static const char readme_msg[] = |
2066 | "tracing mini-HOWTO:\n\n" | |
2067 | "# mkdir /debug\n" | |
2068 | "# mount -t debugfs nodev /debug\n\n" | |
2069 | "# cat /debug/tracing/available_tracers\n" | |
2070 | "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n" | |
2071 | "# cat /debug/tracing/current_tracer\n" | |
2072 | "none\n" | |
2073 | "# echo sched_switch > /debug/tracing/current_tracer\n" | |
2074 | "# cat /debug/tracing/current_tracer\n" | |
2075 | "sched_switch\n" | |
ee6bce52 | 2076 | "# cat /debug/tracing/trace_options\n" |
7bd2f24c | 2077 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
ee6bce52 | 2078 | "# echo print-parent > /debug/tracing/trace_options\n" |
7bd2f24c IM |
2079 | "# echo 1 > /debug/tracing/tracing_enabled\n" |
2080 | "# cat /debug/tracing/trace > /tmp/trace.txt\n" | |
2081 | "echo 0 > /debug/tracing/tracing_enabled\n" | |
2082 | ; | |
2083 | ||
2084 | static ssize_t | |
2085 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2086 | size_t cnt, loff_t *ppos) | |
2087 | { | |
2088 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2089 | readme_msg, strlen(readme_msg)); | |
2090 | } | |
2091 | ||
2092 | static struct file_operations tracing_readme_fops = { | |
c7078de1 IM |
2093 | .open = tracing_open_generic, |
2094 | .read = tracing_readme_read, | |
7bd2f24c IM |
2095 | }; |
2096 | ||
bc0c38d1 SR |
2097 | static ssize_t |
2098 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2099 | size_t cnt, loff_t *ppos) | |
2100 | { | |
bc0c38d1 SR |
2101 | char buf[64]; |
2102 | int r; | |
2103 | ||
9036990d | 2104 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2105 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2106 | } |
2107 | ||
2108 | static ssize_t | |
2109 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2110 | size_t cnt, loff_t *ppos) | |
2111 | { | |
2112 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2113 | char buf[64]; |
c6caeeb1 SR |
2114 | long val; |
2115 | int ret; | |
bc0c38d1 | 2116 | |
cffae437 SR |
2117 | if (cnt >= sizeof(buf)) |
2118 | return -EINVAL; | |
bc0c38d1 SR |
2119 | |
2120 | if (copy_from_user(&buf, ubuf, cnt)) | |
2121 | return -EFAULT; | |
2122 | ||
2123 | buf[cnt] = 0; | |
2124 | ||
c6caeeb1 SR |
2125 | ret = strict_strtoul(buf, 10, &val); |
2126 | if (ret < 0) | |
2127 | return ret; | |
bc0c38d1 SR |
2128 | |
2129 | val = !!val; | |
2130 | ||
2131 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2132 | if (tracer_enabled ^ val) { |
2133 | if (val) { | |
bc0c38d1 | 2134 | tracer_enabled = 1; |
9036990d SR |
2135 | if (current_trace->start) |
2136 | current_trace->start(tr); | |
2137 | tracing_start(); | |
2138 | } else { | |
bc0c38d1 | 2139 | tracer_enabled = 0; |
9036990d SR |
2140 | tracing_stop(); |
2141 | if (current_trace->stop) | |
2142 | current_trace->stop(tr); | |
2143 | } | |
bc0c38d1 SR |
2144 | } |
2145 | mutex_unlock(&trace_types_lock); | |
2146 | ||
2147 | filp->f_pos += cnt; | |
2148 | ||
2149 | return cnt; | |
2150 | } | |
2151 | ||
2152 | static ssize_t | |
2153 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2154 | size_t cnt, loff_t *ppos) | |
2155 | { | |
2156 | char buf[max_tracer_type_len+2]; | |
2157 | int r; | |
2158 | ||
2159 | mutex_lock(&trace_types_lock); | |
2160 | if (current_trace) | |
2161 | r = sprintf(buf, "%s\n", current_trace->name); | |
2162 | else | |
2163 | r = sprintf(buf, "\n"); | |
2164 | mutex_unlock(&trace_types_lock); | |
2165 | ||
4bf39a94 | 2166 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2167 | } |
2168 | ||
d9e54076 | 2169 | static int tracing_set_tracer(char *buf) |
bc0c38d1 SR |
2170 | { |
2171 | struct trace_array *tr = &global_trace; | |
2172 | struct tracer *t; | |
d9e54076 | 2173 | int ret = 0; |
bc0c38d1 SR |
2174 | |
2175 | mutex_lock(&trace_types_lock); | |
2176 | for (t = trace_types; t; t = t->next) { | |
2177 | if (strcmp(t->name, buf) == 0) | |
2178 | break; | |
2179 | } | |
c2931e05 FW |
2180 | if (!t) { |
2181 | ret = -EINVAL; | |
2182 | goto out; | |
2183 | } | |
2184 | if (t == current_trace) | |
bc0c38d1 SR |
2185 | goto out; |
2186 | ||
9f029e83 | 2187 | trace_branch_disable(); |
bc0c38d1 SR |
2188 | if (current_trace && current_trace->reset) |
2189 | current_trace->reset(tr); | |
2190 | ||
2191 | current_trace = t; | |
1c80025a FW |
2192 | if (t->init) { |
2193 | ret = t->init(tr); | |
2194 | if (ret) | |
2195 | goto out; | |
2196 | } | |
bc0c38d1 | 2197 | |
9f029e83 | 2198 | trace_branch_enable(tr); |
bc0c38d1 SR |
2199 | out: |
2200 | mutex_unlock(&trace_types_lock); | |
2201 | ||
d9e54076 PZ |
2202 | return ret; |
2203 | } | |
2204 | ||
2205 | static ssize_t | |
2206 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2207 | size_t cnt, loff_t *ppos) | |
2208 | { | |
2209 | char buf[max_tracer_type_len+1]; | |
2210 | int i; | |
2211 | size_t ret; | |
e6e7a65a FW |
2212 | int err; |
2213 | ||
2214 | ret = cnt; | |
d9e54076 PZ |
2215 | |
2216 | if (cnt > max_tracer_type_len) | |
2217 | cnt = max_tracer_type_len; | |
2218 | ||
2219 | if (copy_from_user(&buf, ubuf, cnt)) | |
2220 | return -EFAULT; | |
2221 | ||
2222 | buf[cnt] = 0; | |
2223 | ||
2224 | /* strip ending whitespace. */ | |
2225 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2226 | buf[i] = 0; | |
2227 | ||
e6e7a65a FW |
2228 | err = tracing_set_tracer(buf); |
2229 | if (err) | |
2230 | return err; | |
d9e54076 | 2231 | |
e6e7a65a | 2232 | filp->f_pos += ret; |
bc0c38d1 | 2233 | |
c2931e05 | 2234 | return ret; |
bc0c38d1 SR |
2235 | } |
2236 | ||
2237 | static ssize_t | |
2238 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2239 | size_t cnt, loff_t *ppos) | |
2240 | { | |
2241 | unsigned long *ptr = filp->private_data; | |
2242 | char buf[64]; | |
2243 | int r; | |
2244 | ||
cffae437 | 2245 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2246 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2247 | if (r > sizeof(buf)) |
2248 | r = sizeof(buf); | |
4bf39a94 | 2249 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2250 | } |
2251 | ||
2252 | static ssize_t | |
2253 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2254 | size_t cnt, loff_t *ppos) | |
2255 | { | |
2256 | long *ptr = filp->private_data; | |
bc0c38d1 | 2257 | char buf[64]; |
c6caeeb1 SR |
2258 | long val; |
2259 | int ret; | |
bc0c38d1 | 2260 | |
cffae437 SR |
2261 | if (cnt >= sizeof(buf)) |
2262 | return -EINVAL; | |
bc0c38d1 SR |
2263 | |
2264 | if (copy_from_user(&buf, ubuf, cnt)) | |
2265 | return -EFAULT; | |
2266 | ||
2267 | buf[cnt] = 0; | |
2268 | ||
c6caeeb1 SR |
2269 | ret = strict_strtoul(buf, 10, &val); |
2270 | if (ret < 0) | |
2271 | return ret; | |
bc0c38d1 SR |
2272 | |
2273 | *ptr = val * 1000; | |
2274 | ||
2275 | return cnt; | |
2276 | } | |
2277 | ||
b3806b43 SR |
2278 | static atomic_t tracing_reader; |
2279 | ||
2280 | static int tracing_open_pipe(struct inode *inode, struct file *filp) | |
2281 | { | |
2282 | struct trace_iterator *iter; | |
2283 | ||
2284 | if (tracing_disabled) | |
2285 | return -ENODEV; | |
2286 | ||
2287 | /* We only allow for reader of the pipe */ | |
2288 | if (atomic_inc_return(&tracing_reader) != 1) { | |
2289 | atomic_dec(&tracing_reader); | |
2290 | return -EBUSY; | |
2291 | } | |
2292 | ||
2293 | /* create a buffer to store the information to pass to userspace */ | |
2294 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
2295 | if (!iter) | |
2296 | return -ENOMEM; | |
2297 | ||
4462344e RR |
2298 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
2299 | kfree(iter); | |
2300 | return -ENOMEM; | |
2301 | } | |
2302 | ||
107bad8b | 2303 | mutex_lock(&trace_types_lock); |
a309720c SR |
2304 | |
2305 | /* trace pipe does not show start of buffer */ | |
4462344e | 2306 | cpumask_setall(iter->started); |
a309720c | 2307 | |
b3806b43 | 2308 | iter->tr = &global_trace; |
72829bc3 | 2309 | iter->trace = current_trace; |
b3806b43 SR |
2310 | filp->private_data = iter; |
2311 | ||
107bad8b SR |
2312 | if (iter->trace->pipe_open) |
2313 | iter->trace->pipe_open(iter); | |
2314 | mutex_unlock(&trace_types_lock); | |
2315 | ||
b3806b43 SR |
2316 | return 0; |
2317 | } | |
2318 | ||
2319 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2320 | { | |
2321 | struct trace_iterator *iter = file->private_data; | |
2322 | ||
4462344e | 2323 | free_cpumask_var(iter->started); |
b3806b43 SR |
2324 | kfree(iter); |
2325 | atomic_dec(&tracing_reader); | |
2326 | ||
2327 | return 0; | |
2328 | } | |
2329 | ||
2a2cc8f7 SSP |
2330 | static unsigned int |
2331 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2332 | { | |
2333 | struct trace_iterator *iter = filp->private_data; | |
2334 | ||
2335 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2336 | /* | |
2337 | * Always select as readable when in blocking mode | |
2338 | */ | |
2339 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2340 | } else { |
2a2cc8f7 SSP |
2341 | if (!trace_empty(iter)) |
2342 | return POLLIN | POLLRDNORM; | |
2343 | poll_wait(filp, &trace_wait, poll_table); | |
2344 | if (!trace_empty(iter)) | |
2345 | return POLLIN | POLLRDNORM; | |
2346 | ||
2347 | return 0; | |
2348 | } | |
2349 | } | |
2350 | ||
b3806b43 SR |
2351 | /* |
2352 | * Consumer reader. | |
2353 | */ | |
2354 | static ssize_t | |
2355 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2356 | size_t cnt, loff_t *ppos) | |
2357 | { | |
2358 | struct trace_iterator *iter = filp->private_data; | |
6c6c2796 | 2359 | ssize_t sret; |
b3806b43 SR |
2360 | |
2361 | /* return any leftover data */ | |
6c6c2796 PP |
2362 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2363 | if (sret != -EBUSY) | |
2364 | return sret; | |
b3806b43 | 2365 | |
6c6c2796 | 2366 | trace_seq_reset(&iter->seq); |
b3806b43 | 2367 | |
107bad8b SR |
2368 | mutex_lock(&trace_types_lock); |
2369 | if (iter->trace->read) { | |
6c6c2796 PP |
2370 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); |
2371 | if (sret) | |
107bad8b | 2372 | goto out; |
107bad8b SR |
2373 | } |
2374 | ||
9ff4b974 PP |
2375 | waitagain: |
2376 | sret = 0; | |
b3806b43 | 2377 | while (trace_empty(iter)) { |
2dc8f095 | 2378 | |
107bad8b | 2379 | if ((filp->f_flags & O_NONBLOCK)) { |
6c6c2796 | 2380 | sret = -EAGAIN; |
107bad8b SR |
2381 | goto out; |
2382 | } | |
2dc8f095 | 2383 | |
b3806b43 SR |
2384 | /* |
2385 | * This is a make-shift waitqueue. The reason we don't use | |
2386 | * an actual wait queue is because: | |
2387 | * 1) we only ever have one waiter | |
2388 | * 2) the tracing, traces all functions, we don't want | |
2389 | * the overhead of calling wake_up and friends | |
2390 | * (and tracing them too) | |
2391 | * Anyway, this is really very primitive wakeup. | |
2392 | */ | |
2393 | set_current_state(TASK_INTERRUPTIBLE); | |
2394 | iter->tr->waiter = current; | |
2395 | ||
107bad8b SR |
2396 | mutex_unlock(&trace_types_lock); |
2397 | ||
9fe068e9 IM |
2398 | /* sleep for 100 msecs, and try again. */ |
2399 | schedule_timeout(HZ/10); | |
b3806b43 | 2400 | |
107bad8b SR |
2401 | mutex_lock(&trace_types_lock); |
2402 | ||
b3806b43 SR |
2403 | iter->tr->waiter = NULL; |
2404 | ||
107bad8b | 2405 | if (signal_pending(current)) { |
6c6c2796 | 2406 | sret = -EINTR; |
107bad8b SR |
2407 | goto out; |
2408 | } | |
b3806b43 | 2409 | |
84527997 | 2410 | if (iter->trace != current_trace) |
107bad8b | 2411 | goto out; |
84527997 | 2412 | |
b3806b43 SR |
2413 | /* |
2414 | * We block until we read something and tracing is disabled. | |
2415 | * We still block if tracing is disabled, but we have never | |
2416 | * read anything. This allows a user to cat this file, and | |
2417 | * then enable tracing. But after we have read something, | |
2418 | * we give an EOF when tracing is again disabled. | |
2419 | * | |
2420 | * iter->pos will be 0 if we haven't read anything. | |
2421 | */ | |
2422 | if (!tracer_enabled && iter->pos) | |
2423 | break; | |
2424 | ||
2425 | continue; | |
2426 | } | |
2427 | ||
2428 | /* stop when tracing is finished */ | |
2429 | if (trace_empty(iter)) | |
107bad8b | 2430 | goto out; |
b3806b43 SR |
2431 | |
2432 | if (cnt >= PAGE_SIZE) | |
2433 | cnt = PAGE_SIZE - 1; | |
2434 | ||
53d0aa77 | 2435 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
2436 | memset(&iter->seq, 0, |
2437 | sizeof(struct trace_iterator) - | |
2438 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 2439 | iter->pos = -1; |
b3806b43 | 2440 | |
088b1e42 | 2441 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 2442 | enum print_line_t ret; |
088b1e42 SR |
2443 | int len = iter->seq.len; |
2444 | ||
f9896bf3 | 2445 | ret = print_trace_line(iter); |
2c4f035f | 2446 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
2447 | /* don't print partial lines */ |
2448 | iter->seq.len = len; | |
b3806b43 | 2449 | break; |
088b1e42 | 2450 | } |
b3806b43 SR |
2451 | |
2452 | trace_consume(iter); | |
2453 | ||
2454 | if (iter->seq.len >= cnt) | |
2455 | break; | |
b3806b43 SR |
2456 | } |
2457 | ||
b3806b43 | 2458 | /* Now copy what we have to the user */ |
6c6c2796 PP |
2459 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2460 | if (iter->seq.readpos >= iter->seq.len) | |
b3806b43 | 2461 | trace_seq_reset(&iter->seq); |
9ff4b974 PP |
2462 | |
2463 | /* | |
2464 | * If there was nothing to send to user, inspite of consuming trace | |
2465 | * entries, go back to wait for more entries. | |
2466 | */ | |
6c6c2796 | 2467 | if (sret == -EBUSY) |
9ff4b974 | 2468 | goto waitagain; |
b3806b43 | 2469 | |
107bad8b SR |
2470 | out: |
2471 | mutex_unlock(&trace_types_lock); | |
2472 | ||
6c6c2796 | 2473 | return sret; |
b3806b43 SR |
2474 | } |
2475 | ||
a98a3c3f SR |
2476 | static ssize_t |
2477 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
2478 | size_t cnt, loff_t *ppos) | |
2479 | { | |
2480 | struct trace_array *tr = filp->private_data; | |
2481 | char buf[64]; | |
2482 | int r; | |
2483 | ||
1696b2b0 | 2484 | r = sprintf(buf, "%lu\n", tr->entries >> 10); |
a98a3c3f SR |
2485 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
2486 | } | |
2487 | ||
2488 | static ssize_t | |
2489 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
2490 | size_t cnt, loff_t *ppos) | |
2491 | { | |
2492 | unsigned long val; | |
2493 | char buf[64]; | |
bf5e6519 | 2494 | int ret, cpu; |
a98a3c3f | 2495 | |
cffae437 SR |
2496 | if (cnt >= sizeof(buf)) |
2497 | return -EINVAL; | |
a98a3c3f SR |
2498 | |
2499 | if (copy_from_user(&buf, ubuf, cnt)) | |
2500 | return -EFAULT; | |
2501 | ||
2502 | buf[cnt] = 0; | |
2503 | ||
c6caeeb1 SR |
2504 | ret = strict_strtoul(buf, 10, &val); |
2505 | if (ret < 0) | |
2506 | return ret; | |
a98a3c3f SR |
2507 | |
2508 | /* must have at least 1 entry */ | |
2509 | if (!val) | |
2510 | return -EINVAL; | |
2511 | ||
2512 | mutex_lock(&trace_types_lock); | |
2513 | ||
c76f0694 | 2514 | tracing_stop(); |
a98a3c3f | 2515 | |
bf5e6519 SR |
2516 | /* disable all cpu buffers */ |
2517 | for_each_tracing_cpu(cpu) { | |
2518 | if (global_trace.data[cpu]) | |
2519 | atomic_inc(&global_trace.data[cpu]->disabled); | |
2520 | if (max_tr.data[cpu]) | |
2521 | atomic_inc(&max_tr.data[cpu]->disabled); | |
2522 | } | |
2523 | ||
1696b2b0 SR |
2524 | /* value is in KB */ |
2525 | val <<= 10; | |
2526 | ||
3928a8a2 SR |
2527 | if (val != global_trace.entries) { |
2528 | ret = ring_buffer_resize(global_trace.buffer, val); | |
2529 | if (ret < 0) { | |
2530 | cnt = ret; | |
3eefae99 SR |
2531 | goto out; |
2532 | } | |
2533 | ||
3928a8a2 SR |
2534 | ret = ring_buffer_resize(max_tr.buffer, val); |
2535 | if (ret < 0) { | |
2536 | int r; | |
2537 | cnt = ret; | |
2538 | r = ring_buffer_resize(global_trace.buffer, | |
2539 | global_trace.entries); | |
2540 | if (r < 0) { | |
2541 | /* AARGH! We are left with different | |
2542 | * size max buffer!!!! */ | |
2543 | WARN_ON(1); | |
2544 | tracing_disabled = 1; | |
a98a3c3f | 2545 | } |
3928a8a2 | 2546 | goto out; |
a98a3c3f | 2547 | } |
3eefae99 | 2548 | |
3928a8a2 | 2549 | global_trace.entries = val; |
a98a3c3f SR |
2550 | } |
2551 | ||
2552 | filp->f_pos += cnt; | |
2553 | ||
19384c03 SR |
2554 | /* If check pages failed, return ENOMEM */ |
2555 | if (tracing_disabled) | |
2556 | cnt = -ENOMEM; | |
a98a3c3f | 2557 | out: |
bf5e6519 SR |
2558 | for_each_tracing_cpu(cpu) { |
2559 | if (global_trace.data[cpu]) | |
2560 | atomic_dec(&global_trace.data[cpu]->disabled); | |
2561 | if (max_tr.data[cpu]) | |
2562 | atomic_dec(&max_tr.data[cpu]->disabled); | |
2563 | } | |
2564 | ||
c76f0694 | 2565 | tracing_start(); |
a98a3c3f SR |
2566 | max_tr.entries = global_trace.entries; |
2567 | mutex_unlock(&trace_types_lock); | |
2568 | ||
2569 | return cnt; | |
2570 | } | |
2571 | ||
5bf9a1ee PP |
2572 | static int mark_printk(const char *fmt, ...) |
2573 | { | |
2574 | int ret; | |
2575 | va_list args; | |
2576 | va_start(args, fmt); | |
1fd8f2a3 | 2577 | ret = trace_vprintk(0, -1, fmt, args); |
5bf9a1ee PP |
2578 | va_end(args); |
2579 | return ret; | |
2580 | } | |
2581 | ||
2582 | static ssize_t | |
2583 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
2584 | size_t cnt, loff_t *fpos) | |
2585 | { | |
2586 | char *buf; | |
2587 | char *end; | |
5bf9a1ee | 2588 | |
c76f0694 | 2589 | if (tracing_disabled) |
5bf9a1ee PP |
2590 | return -EINVAL; |
2591 | ||
2592 | if (cnt > TRACE_BUF_SIZE) | |
2593 | cnt = TRACE_BUF_SIZE; | |
2594 | ||
2595 | buf = kmalloc(cnt + 1, GFP_KERNEL); | |
2596 | if (buf == NULL) | |
2597 | return -ENOMEM; | |
2598 | ||
2599 | if (copy_from_user(buf, ubuf, cnt)) { | |
2600 | kfree(buf); | |
2601 | return -EFAULT; | |
2602 | } | |
2603 | ||
2604 | /* Cut from the first nil or newline. */ | |
2605 | buf[cnt] = '\0'; | |
2606 | end = strchr(buf, '\n'); | |
2607 | if (end) | |
2608 | *end = '\0'; | |
2609 | ||
2610 | cnt = mark_printk("%s\n", buf); | |
2611 | kfree(buf); | |
2612 | *fpos += cnt; | |
2613 | ||
2614 | return cnt; | |
2615 | } | |
2616 | ||
bc0c38d1 | 2617 | static struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
2618 | .open = tracing_open_generic, |
2619 | .read = tracing_max_lat_read, | |
2620 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
2621 | }; |
2622 | ||
2623 | static struct file_operations tracing_ctrl_fops = { | |
4bf39a94 IM |
2624 | .open = tracing_open_generic, |
2625 | .read = tracing_ctrl_read, | |
2626 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
2627 | }; |
2628 | ||
2629 | static struct file_operations set_tracer_fops = { | |
4bf39a94 IM |
2630 | .open = tracing_open_generic, |
2631 | .read = tracing_set_trace_read, | |
2632 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
2633 | }; |
2634 | ||
b3806b43 | 2635 | static struct file_operations tracing_pipe_fops = { |
4bf39a94 | 2636 | .open = tracing_open_pipe, |
2a2cc8f7 | 2637 | .poll = tracing_poll_pipe, |
4bf39a94 IM |
2638 | .read = tracing_read_pipe, |
2639 | .release = tracing_release_pipe, | |
b3806b43 SR |
2640 | }; |
2641 | ||
a98a3c3f SR |
2642 | static struct file_operations tracing_entries_fops = { |
2643 | .open = tracing_open_generic, | |
2644 | .read = tracing_entries_read, | |
2645 | .write = tracing_entries_write, | |
2646 | }; | |
2647 | ||
5bf9a1ee | 2648 | static struct file_operations tracing_mark_fops = { |
43a15386 | 2649 | .open = tracing_open_generic, |
5bf9a1ee PP |
2650 | .write = tracing_mark_write, |
2651 | }; | |
2652 | ||
bc0c38d1 SR |
2653 | #ifdef CONFIG_DYNAMIC_FTRACE |
2654 | ||
b807c3d0 SR |
2655 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
2656 | { | |
2657 | return 0; | |
2658 | } | |
2659 | ||
bc0c38d1 | 2660 | static ssize_t |
b807c3d0 | 2661 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
2662 | size_t cnt, loff_t *ppos) |
2663 | { | |
a26a2a27 SR |
2664 | static char ftrace_dyn_info_buffer[1024]; |
2665 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 2666 | unsigned long *p = filp->private_data; |
b807c3d0 | 2667 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 2668 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
2669 | int r; |
2670 | ||
b807c3d0 SR |
2671 | mutex_lock(&dyn_info_mutex); |
2672 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 2673 | |
a26a2a27 | 2674 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
2675 | buf[r++] = '\n'; |
2676 | ||
2677 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
2678 | ||
2679 | mutex_unlock(&dyn_info_mutex); | |
2680 | ||
2681 | return r; | |
bc0c38d1 SR |
2682 | } |
2683 | ||
b807c3d0 | 2684 | static struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 2685 | .open = tracing_open_generic, |
b807c3d0 | 2686 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
2687 | }; |
2688 | #endif | |
2689 | ||
2690 | static struct dentry *d_tracer; | |
2691 | ||
2692 | struct dentry *tracing_init_dentry(void) | |
2693 | { | |
2694 | static int once; | |
2695 | ||
2696 | if (d_tracer) | |
2697 | return d_tracer; | |
2698 | ||
2699 | d_tracer = debugfs_create_dir("tracing", NULL); | |
2700 | ||
2701 | if (!d_tracer && !once) { | |
2702 | once = 1; | |
2703 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
2704 | return NULL; | |
2705 | } | |
2706 | ||
2707 | return d_tracer; | |
2708 | } | |
2709 | ||
60a11774 SR |
2710 | #ifdef CONFIG_FTRACE_SELFTEST |
2711 | /* Let selftest have access to static functions in this file */ | |
2712 | #include "trace_selftest.c" | |
2713 | #endif | |
2714 | ||
b5ad384e | 2715 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
2716 | { |
2717 | struct dentry *d_tracer; | |
2718 | struct dentry *entry; | |
2719 | ||
2720 | d_tracer = tracing_init_dentry(); | |
2721 | ||
2722 | entry = debugfs_create_file("tracing_enabled", 0644, d_tracer, | |
2723 | &global_trace, &tracing_ctrl_fops); | |
2724 | if (!entry) | |
2725 | pr_warning("Could not create debugfs 'tracing_enabled' entry\n"); | |
2726 | ||
ee6bce52 | 2727 | entry = debugfs_create_file("trace_options", 0644, d_tracer, |
bc0c38d1 SR |
2728 | NULL, &tracing_iter_fops); |
2729 | if (!entry) | |
ee6bce52 | 2730 | pr_warning("Could not create debugfs 'trace_options' entry\n"); |
bc0c38d1 | 2731 | |
c7078de1 IM |
2732 | entry = debugfs_create_file("tracing_cpumask", 0644, d_tracer, |
2733 | NULL, &tracing_cpumask_fops); | |
2734 | if (!entry) | |
2735 | pr_warning("Could not create debugfs 'tracing_cpumask' entry\n"); | |
2736 | ||
bc0c38d1 SR |
2737 | entry = debugfs_create_file("latency_trace", 0444, d_tracer, |
2738 | &global_trace, &tracing_lt_fops); | |
2739 | if (!entry) | |
2740 | pr_warning("Could not create debugfs 'latency_trace' entry\n"); | |
2741 | ||
2742 | entry = debugfs_create_file("trace", 0444, d_tracer, | |
2743 | &global_trace, &tracing_fops); | |
2744 | if (!entry) | |
2745 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2746 | ||
2747 | entry = debugfs_create_file("available_tracers", 0444, d_tracer, | |
2748 | &global_trace, &show_traces_fops); | |
2749 | if (!entry) | |
98a983aa | 2750 | pr_warning("Could not create debugfs 'available_tracers' entry\n"); |
bc0c38d1 SR |
2751 | |
2752 | entry = debugfs_create_file("current_tracer", 0444, d_tracer, | |
2753 | &global_trace, &set_tracer_fops); | |
2754 | if (!entry) | |
98a983aa | 2755 | pr_warning("Could not create debugfs 'current_tracer' entry\n"); |
bc0c38d1 SR |
2756 | |
2757 | entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer, | |
2758 | &tracing_max_latency, | |
2759 | &tracing_max_lat_fops); | |
2760 | if (!entry) | |
2761 | pr_warning("Could not create debugfs " | |
2762 | "'tracing_max_latency' entry\n"); | |
2763 | ||
2764 | entry = debugfs_create_file("tracing_thresh", 0644, d_tracer, | |
2765 | &tracing_thresh, &tracing_max_lat_fops); | |
2766 | if (!entry) | |
2767 | pr_warning("Could not create debugfs " | |
98a983aa | 2768 | "'tracing_thresh' entry\n"); |
7bd2f24c IM |
2769 | entry = debugfs_create_file("README", 0644, d_tracer, |
2770 | NULL, &tracing_readme_fops); | |
2771 | if (!entry) | |
2772 | pr_warning("Could not create debugfs 'README' entry\n"); | |
2773 | ||
b3806b43 SR |
2774 | entry = debugfs_create_file("trace_pipe", 0644, d_tracer, |
2775 | NULL, &tracing_pipe_fops); | |
2776 | if (!entry) | |
2777 | pr_warning("Could not create debugfs " | |
98a983aa | 2778 | "'trace_pipe' entry\n"); |
bc0c38d1 | 2779 | |
a94c80e7 | 2780 | entry = debugfs_create_file("buffer_size_kb", 0644, d_tracer, |
a98a3c3f SR |
2781 | &global_trace, &tracing_entries_fops); |
2782 | if (!entry) | |
2783 | pr_warning("Could not create debugfs " | |
a94c80e7 | 2784 | "'buffer_size_kb' entry\n"); |
a98a3c3f | 2785 | |
5bf9a1ee PP |
2786 | entry = debugfs_create_file("trace_marker", 0220, d_tracer, |
2787 | NULL, &tracing_mark_fops); | |
2788 | if (!entry) | |
2789 | pr_warning("Could not create debugfs " | |
2790 | "'trace_marker' entry\n"); | |
2791 | ||
bc0c38d1 SR |
2792 | #ifdef CONFIG_DYNAMIC_FTRACE |
2793 | entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer, | |
2794 | &ftrace_update_tot_cnt, | |
b807c3d0 | 2795 | &tracing_dyn_info_fops); |
bc0c38d1 SR |
2796 | if (!entry) |
2797 | pr_warning("Could not create debugfs " | |
2798 | "'dyn_ftrace_total_info' entry\n"); | |
2799 | #endif | |
d618b3e6 IM |
2800 | #ifdef CONFIG_SYSPROF_TRACER |
2801 | init_tracer_sysprof_debugfs(d_tracer); | |
2802 | #endif | |
b5ad384e | 2803 | return 0; |
bc0c38d1 SR |
2804 | } |
2805 | ||
1fd8f2a3 | 2806 | int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args) |
dd0e545f | 2807 | { |
dd0e545f SR |
2808 | static DEFINE_SPINLOCK(trace_buf_lock); |
2809 | static char trace_buf[TRACE_BUF_SIZE]; | |
f09ce573 | 2810 | |
3928a8a2 | 2811 | struct ring_buffer_event *event; |
f09ce573 | 2812 | struct trace_array *tr = &global_trace; |
dd0e545f | 2813 | struct trace_array_cpu *data; |
38697053 | 2814 | int cpu, len = 0, size, pc; |
e726f5f9 IM |
2815 | struct print_entry *entry; |
2816 | unsigned long irq_flags; | |
dd0e545f | 2817 | |
8e1b82e0 | 2818 | if (tracing_disabled || tracing_selftest_running) |
dd0e545f SR |
2819 | return 0; |
2820 | ||
38697053 SR |
2821 | pc = preempt_count(); |
2822 | preempt_disable_notrace(); | |
dd0e545f SR |
2823 | cpu = raw_smp_processor_id(); |
2824 | data = tr->data[cpu]; | |
dd0e545f | 2825 | |
3ea2e6d7 | 2826 | if (unlikely(atomic_read(&data->disabled))) |
dd0e545f SR |
2827 | goto out; |
2828 | ||
380c4b14 FW |
2829 | pause_graph_tracing(); |
2830 | spin_lock_irqsave(&trace_buf_lock, irq_flags); | |
801fe400 | 2831 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
dd0e545f SR |
2832 | |
2833 | len = min(len, TRACE_BUF_SIZE-1); | |
2834 | trace_buf[len] = 0; | |
2835 | ||
777e208d SR |
2836 | size = sizeof(*entry) + len + 1; |
2837 | event = ring_buffer_lock_reserve(tr->buffer, size, &irq_flags); | |
3928a8a2 SR |
2838 | if (!event) |
2839 | goto out_unlock; | |
777e208d | 2840 | entry = ring_buffer_event_data(event); |
e726f5f9 | 2841 | tracing_generic_entry_update(&entry->ent, irq_flags, pc); |
777e208d SR |
2842 | entry->ent.type = TRACE_PRINT; |
2843 | entry->ip = ip; | |
1fd8f2a3 | 2844 | entry->depth = depth; |
dd0e545f | 2845 | |
777e208d SR |
2846 | memcpy(&entry->buf, trace_buf, len); |
2847 | entry->buf[len] = 0; | |
3928a8a2 | 2848 | ring_buffer_unlock_commit(tr->buffer, event, irq_flags); |
dd0e545f | 2849 | |
3928a8a2 | 2850 | out_unlock: |
380c4b14 FW |
2851 | spin_unlock_irqrestore(&trace_buf_lock, irq_flags); |
2852 | unpause_graph_tracing(); | |
dd0e545f | 2853 | out: |
38697053 | 2854 | preempt_enable_notrace(); |
dd0e545f SR |
2855 | |
2856 | return len; | |
2857 | } | |
801fe400 PP |
2858 | EXPORT_SYMBOL_GPL(trace_vprintk); |
2859 | ||
2860 | int __ftrace_printk(unsigned long ip, const char *fmt, ...) | |
2861 | { | |
2862 | int ret; | |
2863 | va_list ap; | |
2864 | ||
2865 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2866 | return 0; | |
2867 | ||
2868 | va_start(ap, fmt); | |
21a8c466 | 2869 | ret = trace_vprintk(ip, task_curr_ret_stack(current), fmt, ap); |
801fe400 PP |
2870 | va_end(ap); |
2871 | return ret; | |
2872 | } | |
dd0e545f SR |
2873 | EXPORT_SYMBOL_GPL(__ftrace_printk); |
2874 | ||
9011262a ACM |
2875 | int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap) |
2876 | { | |
2877 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
2878 | return 0; | |
2879 | ||
2880 | return trace_vprintk(ip, task_curr_ret_stack(current), fmt, ap); | |
2881 | } | |
2882 | EXPORT_SYMBOL_GPL(__ftrace_vprintk); | |
2883 | ||
3f5a54e3 SR |
2884 | static int trace_panic_handler(struct notifier_block *this, |
2885 | unsigned long event, void *unused) | |
2886 | { | |
944ac425 SR |
2887 | if (ftrace_dump_on_oops) |
2888 | ftrace_dump(); | |
3f5a54e3 SR |
2889 | return NOTIFY_OK; |
2890 | } | |
2891 | ||
2892 | static struct notifier_block trace_panic_notifier = { | |
2893 | .notifier_call = trace_panic_handler, | |
2894 | .next = NULL, | |
2895 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
2896 | }; | |
2897 | ||
2898 | static int trace_die_handler(struct notifier_block *self, | |
2899 | unsigned long val, | |
2900 | void *data) | |
2901 | { | |
2902 | switch (val) { | |
2903 | case DIE_OOPS: | |
944ac425 SR |
2904 | if (ftrace_dump_on_oops) |
2905 | ftrace_dump(); | |
3f5a54e3 SR |
2906 | break; |
2907 | default: | |
2908 | break; | |
2909 | } | |
2910 | return NOTIFY_OK; | |
2911 | } | |
2912 | ||
2913 | static struct notifier_block trace_die_notifier = { | |
2914 | .notifier_call = trace_die_handler, | |
2915 | .priority = 200 | |
2916 | }; | |
2917 | ||
2918 | /* | |
2919 | * printk is set to max of 1024, we really don't need it that big. | |
2920 | * Nothing should be printing 1000 characters anyway. | |
2921 | */ | |
2922 | #define TRACE_MAX_PRINT 1000 | |
2923 | ||
2924 | /* | |
2925 | * Define here KERN_TRACE so that we have one place to modify | |
2926 | * it if we decide to change what log level the ftrace dump | |
2927 | * should be at. | |
2928 | */ | |
428aee14 | 2929 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
2930 | |
2931 | static void | |
2932 | trace_printk_seq(struct trace_seq *s) | |
2933 | { | |
2934 | /* Probably should print a warning here. */ | |
2935 | if (s->len >= 1000) | |
2936 | s->len = 1000; | |
2937 | ||
2938 | /* should be zero ended, but we are paranoid. */ | |
2939 | s->buffer[s->len] = 0; | |
2940 | ||
2941 | printk(KERN_TRACE "%s", s->buffer); | |
2942 | ||
2943 | trace_seq_reset(s); | |
2944 | } | |
2945 | ||
3f5a54e3 SR |
2946 | void ftrace_dump(void) |
2947 | { | |
2948 | static DEFINE_SPINLOCK(ftrace_dump_lock); | |
2949 | /* use static because iter can be a bit big for the stack */ | |
2950 | static struct trace_iterator iter; | |
3f5a54e3 | 2951 | static int dump_ran; |
d769041f SR |
2952 | unsigned long flags; |
2953 | int cnt = 0, cpu; | |
3f5a54e3 SR |
2954 | |
2955 | /* only one dump */ | |
2956 | spin_lock_irqsave(&ftrace_dump_lock, flags); | |
2957 | if (dump_ran) | |
2958 | goto out; | |
2959 | ||
2960 | dump_ran = 1; | |
2961 | ||
2962 | /* No turning back! */ | |
0ee6b6cf | 2963 | tracing_off(); |
81adbdc0 | 2964 | ftrace_kill(); |
3f5a54e3 | 2965 | |
d769041f SR |
2966 | for_each_tracing_cpu(cpu) { |
2967 | atomic_inc(&global_trace.data[cpu]->disabled); | |
2968 | } | |
2969 | ||
b54d3de9 TE |
2970 | /* don't look at user memory in panic mode */ |
2971 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
2972 | ||
3f5a54e3 SR |
2973 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
2974 | ||
2975 | iter.tr = &global_trace; | |
2976 | iter.trace = current_trace; | |
2977 | ||
2978 | /* | |
2979 | * We need to stop all tracing on all CPUS to read the | |
2980 | * the next buffer. This is a bit expensive, but is | |
2981 | * not done often. We fill all what we can read, | |
2982 | * and then release the locks again. | |
2983 | */ | |
2984 | ||
3f5a54e3 SR |
2985 | while (!trace_empty(&iter)) { |
2986 | ||
2987 | if (!cnt) | |
2988 | printk(KERN_TRACE "---------------------------------\n"); | |
2989 | ||
2990 | cnt++; | |
2991 | ||
2992 | /* reset all but tr, trace, and overruns */ | |
2993 | memset(&iter.seq, 0, | |
2994 | sizeof(struct trace_iterator) - | |
2995 | offsetof(struct trace_iterator, seq)); | |
2996 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
2997 | iter.pos = -1; | |
2998 | ||
2999 | if (find_next_entry_inc(&iter) != NULL) { | |
3000 | print_trace_line(&iter); | |
3001 | trace_consume(&iter); | |
3002 | } | |
3003 | ||
3004 | trace_printk_seq(&iter.seq); | |
3005 | } | |
3006 | ||
3007 | if (!cnt) | |
3008 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
3009 | else | |
3010 | printk(KERN_TRACE "---------------------------------\n"); | |
3011 | ||
3f5a54e3 SR |
3012 | out: |
3013 | spin_unlock_irqrestore(&ftrace_dump_lock, flags); | |
3014 | } | |
3015 | ||
3928a8a2 | 3016 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 3017 | { |
4c11d7ae | 3018 | struct trace_array_cpu *data; |
4c11d7ae | 3019 | int i; |
9e01c1b7 | 3020 | int ret = -ENOMEM; |
4c11d7ae | 3021 | |
9e01c1b7 RR |
3022 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
3023 | goto out; | |
3024 | ||
3025 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
3026 | goto out_free_buffer_mask; | |
4c11d7ae | 3027 | |
9e01c1b7 RR |
3028 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
3029 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
3030 | ||
3031 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
3928a8a2 SR |
3032 | global_trace.buffer = ring_buffer_alloc(trace_buf_size, |
3033 | TRACE_BUFFER_FLAGS); | |
3034 | if (!global_trace.buffer) { | |
3035 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
3036 | WARN_ON(1); | |
9e01c1b7 | 3037 | goto out_free_cpumask; |
4c11d7ae | 3038 | } |
3928a8a2 | 3039 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 3040 | |
9e01c1b7 | 3041 | |
4c11d7ae | 3042 | #ifdef CONFIG_TRACER_MAX_TRACE |
3928a8a2 SR |
3043 | max_tr.buffer = ring_buffer_alloc(trace_buf_size, |
3044 | TRACE_BUFFER_FLAGS); | |
3045 | if (!max_tr.buffer) { | |
3046 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
3047 | WARN_ON(1); | |
3048 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 3049 | goto out_free_cpumask; |
4c11d7ae | 3050 | } |
3928a8a2 SR |
3051 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
3052 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 3053 | #endif |
ab46428c | 3054 | |
4c11d7ae | 3055 | /* Allocate the first page for all buffers */ |
ab46428c | 3056 | for_each_tracing_cpu(i) { |
4c11d7ae | 3057 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 | 3058 | max_tr.data[i] = &per_cpu(max_data, i); |
4c11d7ae | 3059 | } |
bc0c38d1 | 3060 | |
bc0c38d1 SR |
3061 | trace_init_cmdlines(); |
3062 | ||
43a15386 | 3063 | register_tracer(&nop_trace); |
b5ad384e FW |
3064 | #ifdef CONFIG_BOOT_TRACER |
3065 | register_tracer(&boot_tracer); | |
3066 | current_trace = &boot_tracer; | |
3067 | current_trace->init(&global_trace); | |
3068 | #else | |
43a15386 | 3069 | current_trace = &nop_trace; |
b5ad384e | 3070 | #endif |
60a11774 SR |
3071 | /* All seems OK, enable tracing */ |
3072 | tracing_disabled = 0; | |
3928a8a2 | 3073 | |
3f5a54e3 SR |
3074 | atomic_notifier_chain_register(&panic_notifier_list, |
3075 | &trace_panic_notifier); | |
3076 | ||
3077 | register_die_notifier(&trace_die_notifier); | |
9e01c1b7 | 3078 | ret = 0; |
3f5a54e3 | 3079 | |
9e01c1b7 RR |
3080 | out_free_cpumask: |
3081 | free_cpumask_var(tracing_cpumask); | |
3082 | out_free_buffer_mask: | |
3083 | free_cpumask_var(tracing_buffer_mask); | |
3084 | out: | |
3085 | return ret; | |
bc0c38d1 | 3086 | } |
b5ad384e FW |
3087 | early_initcall(tracer_alloc_buffers); |
3088 | fs_initcall(tracer_init_debugfs); |