]>
Commit | Line | Data |
---|---|---|
bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
bc0c38d1 | 15 | #include <linux/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
4c11d7ae | 23 | #include <linux/pagemap.h> |
bc0c38d1 SR |
24 | #include <linux/hardirq.h> |
25 | #include <linux/linkage.h> | |
26 | #include <linux/uaccess.h> | |
2cadf913 | 27 | #include <linux/kprobes.h> |
bc0c38d1 SR |
28 | #include <linux/ftrace.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/percpu.h> | |
2cadf913 | 31 | #include <linux/splice.h> |
3f5a54e3 | 32 | #include <linux/kdebug.h> |
bc0c38d1 SR |
33 | #include <linux/ctype.h> |
34 | #include <linux/init.h> | |
2a2cc8f7 | 35 | #include <linux/poll.h> |
bc0c38d1 SR |
36 | #include <linux/gfp.h> |
37 | #include <linux/fs.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 | ||
73c5162a SR |
47 | /* |
48 | * On boot up, the ring buffer is set to the minimum size, so that | |
49 | * we do not waste memory on systems that are not using tracing. | |
50 | */ | |
51 | static int ring_buffer_expanded; | |
52 | ||
8e1b82e0 FW |
53 | /* |
54 | * We need to change this state when a selftest is running. | |
ff32504f FW |
55 | * A selftest will lurk into the ring-buffer to count the |
56 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 57 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
58 | * at the same time, giving false positive or negative results. |
59 | */ | |
8e1b82e0 | 60 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 61 | |
b2821ae6 SR |
62 | /* |
63 | * If a tracer is running, we do not want to run SELFTEST. | |
64 | */ | |
65 | static bool __read_mostly tracing_selftest_disabled; | |
66 | ||
adf9f195 FW |
67 | /* For tracers that don't implement custom flags */ |
68 | static struct tracer_opt dummy_tracer_opt[] = { | |
69 | { } | |
70 | }; | |
71 | ||
72 | static struct tracer_flags dummy_tracer_flags = { | |
73 | .val = 0, | |
74 | .opts = dummy_tracer_opt | |
75 | }; | |
76 | ||
77 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
78 | { | |
79 | return 0; | |
80 | } | |
0f048701 SR |
81 | |
82 | /* | |
83 | * Kill all tracing for good (never come back). | |
84 | * It is initialized to 1 but will turn to zero if the initialization | |
85 | * of the tracer is successful. But that is the only place that sets | |
86 | * this back to zero. | |
87 | */ | |
4fd27358 | 88 | static int tracing_disabled = 1; |
0f048701 | 89 | |
d769041f SR |
90 | static DEFINE_PER_CPU(local_t, ftrace_cpu_disabled); |
91 | ||
92 | static inline void ftrace_disable_cpu(void) | |
93 | { | |
94 | preempt_disable(); | |
95 | local_inc(&__get_cpu_var(ftrace_cpu_disabled)); | |
96 | } | |
97 | ||
98 | static inline void ftrace_enable_cpu(void) | |
99 | { | |
100 | local_dec(&__get_cpu_var(ftrace_cpu_disabled)); | |
101 | preempt_enable(); | |
102 | } | |
103 | ||
9e01c1b7 | 104 | static cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 105 | |
b04cc6b1 FW |
106 | /* Define which cpu buffers are currently read in trace_pipe */ |
107 | static cpumask_var_t tracing_reader_cpumask; | |
108 | ||
ab46428c | 109 | #define for_each_tracing_cpu(cpu) \ |
9e01c1b7 | 110 | for_each_cpu(cpu, tracing_buffer_mask) |
ab46428c | 111 | |
944ac425 SR |
112 | /* |
113 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
114 | * | |
115 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
116 | * is set, then ftrace_dump is called. This will output the contents | |
117 | * of the ftrace buffers to the console. This is very useful for | |
118 | * capturing traces that lead to crashes and outputing it to a | |
119 | * serial console. | |
120 | * | |
121 | * It is default off, but you can enable it with either specifying | |
122 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
123 | * /proc/sys/kernel/ftrace_dump_on_oops to true. | |
124 | */ | |
125 | int ftrace_dump_on_oops; | |
126 | ||
b2821ae6 SR |
127 | static int tracing_set_tracer(const char *buf); |
128 | ||
129 | #define BOOTUP_TRACER_SIZE 100 | |
130 | static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata; | |
131 | static char *default_bootup_tracer; | |
d9e54076 PZ |
132 | |
133 | static int __init set_ftrace(char *str) | |
134 | { | |
b2821ae6 SR |
135 | strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); |
136 | default_bootup_tracer = bootup_tracer_buf; | |
73c5162a SR |
137 | /* We are using ftrace early, expand it */ |
138 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
139 | return 1; |
140 | } | |
b2821ae6 | 141 | __setup("ftrace=", set_ftrace); |
d9e54076 | 142 | |
944ac425 SR |
143 | static int __init set_ftrace_dump_on_oops(char *str) |
144 | { | |
145 | ftrace_dump_on_oops = 1; | |
146 | return 1; | |
147 | } | |
148 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 149 | |
72829bc3 | 150 | long |
bc0c38d1 SR |
151 | ns2usecs(cycle_t nsec) |
152 | { | |
153 | nsec += 500; | |
154 | do_div(nsec, 1000); | |
155 | return nsec; | |
156 | } | |
157 | ||
4fcdae83 SR |
158 | /* |
159 | * The global_trace is the descriptor that holds the tracing | |
160 | * buffers for the live tracing. For each CPU, it contains | |
161 | * a link list of pages that will store trace entries. The | |
162 | * page descriptor of the pages in the memory is used to hold | |
163 | * the link list by linking the lru item in the page descriptor | |
164 | * to each of the pages in the buffer per CPU. | |
165 | * | |
166 | * For each active CPU there is a data field that holds the | |
167 | * pages for the buffer for that CPU. Each CPU has the same number | |
168 | * of pages allocated for its buffer. | |
169 | */ | |
bc0c38d1 SR |
170 | static struct trace_array global_trace; |
171 | ||
172 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
173 | ||
37886f6a SR |
174 | cycle_t ftrace_now(int cpu) |
175 | { | |
176 | u64 ts; | |
177 | ||
178 | /* Early boot up does not have a buffer yet */ | |
179 | if (!global_trace.buffer) | |
180 | return trace_clock_local(); | |
181 | ||
182 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
183 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
184 | ||
185 | return ts; | |
186 | } | |
bc0c38d1 | 187 | |
4fcdae83 SR |
188 | /* |
189 | * The max_tr is used to snapshot the global_trace when a maximum | |
190 | * latency is reached. Some tracers will use this to store a maximum | |
191 | * trace while it continues examining live traces. | |
192 | * | |
193 | * The buffers for the max_tr are set up the same as the global_trace. | |
194 | * When a snapshot is taken, the link list of the max_tr is swapped | |
195 | * with the link list of the global_trace and the buffers are reset for | |
196 | * the global_trace so the tracing can continue. | |
197 | */ | |
bc0c38d1 SR |
198 | static struct trace_array max_tr; |
199 | ||
200 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
201 | ||
4fcdae83 | 202 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 203 | static int tracer_enabled = 1; |
4fcdae83 | 204 | |
9036990d SR |
205 | /** |
206 | * tracing_is_enabled - return tracer_enabled status | |
207 | * | |
208 | * This function is used by other tracers to know the status | |
209 | * of the tracer_enabled flag. Tracers may use this function | |
210 | * to know if it should enable their features when starting | |
211 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
212 | */ | |
213 | int tracing_is_enabled(void) | |
214 | { | |
215 | return tracer_enabled; | |
216 | } | |
217 | ||
4fcdae83 | 218 | /* |
3928a8a2 SR |
219 | * trace_buf_size is the size in bytes that is allocated |
220 | * for a buffer. Note, the number of bytes is always rounded | |
221 | * to page size. | |
3f5a54e3 SR |
222 | * |
223 | * This number is purposely set to a low number of 16384. | |
224 | * If the dump on oops happens, it will be much appreciated | |
225 | * to not have to wait for all that output. Anyway this can be | |
226 | * boot time and run time configurable. | |
4fcdae83 | 227 | */ |
3928a8a2 | 228 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 229 | |
3928a8a2 | 230 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 231 | |
4fcdae83 | 232 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 233 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
234 | |
235 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 236 | static struct tracer *current_trace __read_mostly; |
4fcdae83 SR |
237 | |
238 | /* | |
239 | * max_tracer_type_len is used to simplify the allocating of | |
240 | * buffers to read userspace tracer names. We keep track of | |
241 | * the longest tracer name registered. | |
242 | */ | |
bc0c38d1 SR |
243 | static int max_tracer_type_len; |
244 | ||
4fcdae83 SR |
245 | /* |
246 | * trace_types_lock is used to protect the trace_types list. | |
247 | * This lock is also used to keep user access serialized. | |
248 | * Accesses from userspace will grab this lock while userspace | |
249 | * activities happen inside the kernel. | |
250 | */ | |
bc0c38d1 | 251 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
252 | |
253 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
254 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
255 | ||
ee6bce52 | 256 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 257 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
be6f164a | 258 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME; |
4e655519 | 259 | |
4fcdae83 SR |
260 | /** |
261 | * trace_wake_up - wake up tasks waiting for trace input | |
262 | * | |
263 | * Simply wakes up any task that is blocked on the trace_wait | |
264 | * queue. These is used with trace_poll for tasks polling the trace. | |
265 | */ | |
4e655519 IM |
266 | void trace_wake_up(void) |
267 | { | |
017730c1 IM |
268 | /* |
269 | * The runqueue_is_locked() can fail, but this is the best we | |
270 | * have for now: | |
271 | */ | |
272 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
273 | wake_up(&trace_wait); |
274 | } | |
bc0c38d1 | 275 | |
3928a8a2 | 276 | static int __init set_buf_size(char *str) |
bc0c38d1 | 277 | { |
3928a8a2 | 278 | unsigned long buf_size; |
c6caeeb1 SR |
279 | int ret; |
280 | ||
bc0c38d1 SR |
281 | if (!str) |
282 | return 0; | |
3928a8a2 | 283 | ret = strict_strtoul(str, 0, &buf_size); |
c6caeeb1 | 284 | /* nr_entries can not be zero */ |
3928a8a2 | 285 | if (ret < 0 || buf_size == 0) |
c6caeeb1 | 286 | return 0; |
3928a8a2 | 287 | trace_buf_size = buf_size; |
bc0c38d1 SR |
288 | return 1; |
289 | } | |
3928a8a2 | 290 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 291 | |
57f50be1 SR |
292 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
293 | { | |
294 | return nsecs / 1000; | |
295 | } | |
296 | ||
4fcdae83 | 297 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
298 | static const char *trace_options[] = { |
299 | "print-parent", | |
300 | "sym-offset", | |
301 | "sym-addr", | |
302 | "verbose", | |
f9896bf3 | 303 | "raw", |
5e3ca0ec | 304 | "hex", |
cb0f12aa | 305 | "bin", |
2a2cc8f7 | 306 | "block", |
86387f7e | 307 | "stacktrace", |
4ac3ba41 | 308 | "sched-tree", |
5e1607a0 | 309 | "trace_printk", |
b2a866f9 | 310 | "ftrace_preempt", |
9f029e83 | 311 | "branch", |
12ef7d44 | 312 | "annotate", |
02b67518 | 313 | "userstacktrace", |
b54d3de9 | 314 | "sym-userobj", |
66896a85 | 315 | "printk-msg-only", |
c4a8e8be | 316 | "context-info", |
c032ef64 | 317 | "latency-format", |
af4617bd | 318 | "global-clock", |
be6f164a | 319 | "sleep-time", |
bc0c38d1 SR |
320 | NULL |
321 | }; | |
322 | ||
4fcdae83 SR |
323 | /* |
324 | * ftrace_max_lock is used to protect the swapping of buffers | |
325 | * when taking a max snapshot. The buffers themselves are | |
326 | * protected by per_cpu spinlocks. But the action of the swap | |
327 | * needs its own lock. | |
328 | * | |
329 | * This is defined as a raw_spinlock_t in order to help | |
330 | * with performance when lockdep debugging is enabled. | |
331 | */ | |
92205c23 SR |
332 | static raw_spinlock_t ftrace_max_lock = |
333 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
bc0c38d1 SR |
334 | |
335 | /* | |
336 | * Copy the new maximum trace into the separate maximum-trace | |
337 | * structure. (this way the maximum trace is permanently saved, | |
338 | * for later retrieval via /debugfs/tracing/latency_trace) | |
339 | */ | |
e309b41d | 340 | static void |
bc0c38d1 SR |
341 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
342 | { | |
343 | struct trace_array_cpu *data = tr->data[cpu]; | |
344 | ||
345 | max_tr.cpu = cpu; | |
346 | max_tr.time_start = data->preempt_timestamp; | |
347 | ||
348 | data = max_tr.data[cpu]; | |
349 | data->saved_latency = tracing_max_latency; | |
350 | ||
351 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
352 | data->pid = tsk->pid; | |
b6dff3ec | 353 | data->uid = task_uid(tsk); |
bc0c38d1 SR |
354 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
355 | data->policy = tsk->policy; | |
356 | data->rt_priority = tsk->rt_priority; | |
357 | ||
358 | /* record this tasks comm */ | |
af513098 | 359 | tracing_record_cmdline(tsk); |
bc0c38d1 SR |
360 | } |
361 | ||
6c6c2796 PP |
362 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
363 | { | |
364 | int len; | |
365 | int ret; | |
366 | ||
2dc5d12b SR |
367 | if (!cnt) |
368 | return 0; | |
369 | ||
6c6c2796 PP |
370 | if (s->len <= s->readpos) |
371 | return -EBUSY; | |
372 | ||
373 | len = s->len - s->readpos; | |
374 | if (cnt > len) | |
375 | cnt = len; | |
376 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 377 | if (ret == cnt) |
6c6c2796 PP |
378 | return -EFAULT; |
379 | ||
2dc5d12b SR |
380 | cnt -= ret; |
381 | ||
e74da523 | 382 | s->readpos += cnt; |
6c6c2796 | 383 | return cnt; |
214023c3 SR |
384 | } |
385 | ||
b8b94265 | 386 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
387 | { |
388 | int len; | |
389 | void *ret; | |
390 | ||
391 | if (s->len <= s->readpos) | |
392 | return -EBUSY; | |
393 | ||
394 | len = s->len - s->readpos; | |
395 | if (cnt > len) | |
396 | cnt = len; | |
397 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
398 | if (!ret) | |
399 | return -EFAULT; | |
400 | ||
e74da523 | 401 | s->readpos += cnt; |
3c56819b EGM |
402 | return cnt; |
403 | } | |
404 | ||
4fcdae83 SR |
405 | /** |
406 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
407 | * @tr: tracer | |
408 | * @tsk: the task with the latency | |
409 | * @cpu: The cpu that initiated the trace. | |
410 | * | |
411 | * Flip the buffers between the @tr and the max_tr and record information | |
412 | * about which task was the cause of this latency. | |
413 | */ | |
e309b41d | 414 | void |
bc0c38d1 SR |
415 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
416 | { | |
3928a8a2 | 417 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 418 | |
4c11d7ae | 419 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 420 | __raw_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
421 | |
422 | tr->buffer = max_tr.buffer; | |
423 | max_tr.buffer = buf; | |
424 | ||
d769041f | 425 | ftrace_disable_cpu(); |
3928a8a2 | 426 | ring_buffer_reset(tr->buffer); |
d769041f | 427 | ftrace_enable_cpu(); |
bc0c38d1 SR |
428 | |
429 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 430 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
431 | } |
432 | ||
433 | /** | |
434 | * update_max_tr_single - only copy one trace over, and reset the rest | |
435 | * @tr - tracer | |
436 | * @tsk - task with the latency | |
437 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
438 | * |
439 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 440 | */ |
e309b41d | 441 | void |
bc0c38d1 SR |
442 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
443 | { | |
3928a8a2 | 444 | int ret; |
bc0c38d1 | 445 | |
4c11d7ae | 446 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 447 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 448 | |
d769041f SR |
449 | ftrace_disable_cpu(); |
450 | ||
3928a8a2 SR |
451 | ring_buffer_reset(max_tr.buffer); |
452 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); | |
453 | ||
d769041f SR |
454 | ftrace_enable_cpu(); |
455 | ||
97b17efe | 456 | WARN_ON_ONCE(ret && ret != -EAGAIN); |
bc0c38d1 SR |
457 | |
458 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 459 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
460 | } |
461 | ||
4fcdae83 SR |
462 | /** |
463 | * register_tracer - register a tracer with the ftrace system. | |
464 | * @type - the plugin for the tracer | |
465 | * | |
466 | * Register a new plugin tracer. | |
467 | */ | |
bc0c38d1 | 468 | int register_tracer(struct tracer *type) |
e7669b8e HE |
469 | __releases(kernel_lock) |
470 | __acquires(kernel_lock) | |
bc0c38d1 SR |
471 | { |
472 | struct tracer *t; | |
473 | int len; | |
474 | int ret = 0; | |
475 | ||
476 | if (!type->name) { | |
477 | pr_info("Tracer must have a name\n"); | |
478 | return -1; | |
479 | } | |
480 | ||
86fa2f60 IM |
481 | /* |
482 | * When this gets called we hold the BKL which means that | |
483 | * preemption is disabled. Various trace selftests however | |
484 | * need to disable and enable preemption for successful tests. | |
485 | * So we drop the BKL here and grab it after the tests again. | |
486 | */ | |
487 | unlock_kernel(); | |
bc0c38d1 | 488 | mutex_lock(&trace_types_lock); |
86fa2f60 | 489 | |
8e1b82e0 FW |
490 | tracing_selftest_running = true; |
491 | ||
bc0c38d1 SR |
492 | for (t = trace_types; t; t = t->next) { |
493 | if (strcmp(type->name, t->name) == 0) { | |
494 | /* already found */ | |
495 | pr_info("Trace %s already registered\n", | |
496 | type->name); | |
497 | ret = -1; | |
498 | goto out; | |
499 | } | |
500 | } | |
501 | ||
adf9f195 FW |
502 | if (!type->set_flag) |
503 | type->set_flag = &dummy_set_flag; | |
504 | if (!type->flags) | |
505 | type->flags = &dummy_tracer_flags; | |
506 | else | |
507 | if (!type->flags->opts) | |
508 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
509 | if (!type->wait_pipe) |
510 | type->wait_pipe = default_wait_pipe; | |
511 | ||
adf9f195 | 512 | |
60a11774 | 513 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 514 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 515 | struct tracer *saved_tracer = current_trace; |
60a11774 | 516 | struct trace_array *tr = &global_trace; |
60a11774 | 517 | int i; |
ff32504f | 518 | |
60a11774 SR |
519 | /* |
520 | * Run a selftest on this tracer. | |
521 | * Here we reset the trace buffer, and set the current | |
522 | * tracer to be this tracer. The tracer can then run some | |
523 | * internal tracing to verify that everything is in order. | |
524 | * If we fail, we do not register this tracer. | |
525 | */ | |
86fa2f60 | 526 | for_each_tracing_cpu(i) |
3928a8a2 | 527 | tracing_reset(tr, i); |
86fa2f60 | 528 | |
60a11774 | 529 | current_trace = type; |
60a11774 SR |
530 | /* the test is responsible for initializing and enabling */ |
531 | pr_info("Testing tracer %s: ", type->name); | |
532 | ret = type->selftest(type, tr); | |
533 | /* the test is responsible for resetting too */ | |
534 | current_trace = saved_tracer; | |
60a11774 SR |
535 | if (ret) { |
536 | printk(KERN_CONT "FAILED!\n"); | |
537 | goto out; | |
538 | } | |
1d4db00a | 539 | /* Only reset on passing, to avoid touching corrupted buffers */ |
86fa2f60 | 540 | for_each_tracing_cpu(i) |
3928a8a2 | 541 | tracing_reset(tr, i); |
86fa2f60 | 542 | |
60a11774 SR |
543 | printk(KERN_CONT "PASSED\n"); |
544 | } | |
545 | #endif | |
546 | ||
bc0c38d1 SR |
547 | type->next = trace_types; |
548 | trace_types = type; | |
549 | len = strlen(type->name); | |
550 | if (len > max_tracer_type_len) | |
551 | max_tracer_type_len = len; | |
60a11774 | 552 | |
bc0c38d1 | 553 | out: |
8e1b82e0 | 554 | tracing_selftest_running = false; |
bc0c38d1 SR |
555 | mutex_unlock(&trace_types_lock); |
556 | ||
dac74940 SR |
557 | if (ret || !default_bootup_tracer) |
558 | goto out_unlock; | |
559 | ||
560 | if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE)) | |
561 | goto out_unlock; | |
562 | ||
563 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
564 | /* Do we want this tracer to start on bootup? */ | |
565 | tracing_set_tracer(type->name); | |
566 | default_bootup_tracer = NULL; | |
567 | /* disable other selftests, since this will break it. */ | |
568 | tracing_selftest_disabled = 1; | |
b2821ae6 | 569 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
570 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
571 | type->name); | |
b2821ae6 | 572 | #endif |
b2821ae6 | 573 | |
dac74940 | 574 | out_unlock: |
b2821ae6 | 575 | lock_kernel(); |
bc0c38d1 SR |
576 | return ret; |
577 | } | |
578 | ||
579 | void unregister_tracer(struct tracer *type) | |
580 | { | |
581 | struct tracer **t; | |
582 | int len; | |
583 | ||
584 | mutex_lock(&trace_types_lock); | |
585 | for (t = &trace_types; *t; t = &(*t)->next) { | |
586 | if (*t == type) | |
587 | goto found; | |
588 | } | |
589 | pr_info("Trace %s not registered\n", type->name); | |
590 | goto out; | |
591 | ||
592 | found: | |
593 | *t = (*t)->next; | |
b5db03c4 ACM |
594 | |
595 | if (type == current_trace && tracer_enabled) { | |
596 | tracer_enabled = 0; | |
597 | tracing_stop(); | |
598 | if (current_trace->stop) | |
599 | current_trace->stop(&global_trace); | |
600 | current_trace = &nop_trace; | |
601 | } | |
602 | ||
bc0c38d1 SR |
603 | if (strlen(type->name) != max_tracer_type_len) |
604 | goto out; | |
605 | ||
606 | max_tracer_type_len = 0; | |
607 | for (t = &trace_types; *t; t = &(*t)->next) { | |
608 | len = strlen((*t)->name); | |
609 | if (len > max_tracer_type_len) | |
610 | max_tracer_type_len = len; | |
611 | } | |
612 | out: | |
613 | mutex_unlock(&trace_types_lock); | |
614 | } | |
615 | ||
3928a8a2 | 616 | void tracing_reset(struct trace_array *tr, int cpu) |
bc0c38d1 | 617 | { |
d769041f | 618 | ftrace_disable_cpu(); |
3928a8a2 | 619 | ring_buffer_reset_cpu(tr->buffer, cpu); |
d769041f | 620 | ftrace_enable_cpu(); |
bc0c38d1 SR |
621 | } |
622 | ||
213cc060 PE |
623 | void tracing_reset_online_cpus(struct trace_array *tr) |
624 | { | |
625 | int cpu; | |
626 | ||
627 | tr->time_start = ftrace_now(tr->cpu); | |
628 | ||
629 | for_each_online_cpu(cpu) | |
630 | tracing_reset(tr, cpu); | |
631 | } | |
632 | ||
bc0c38d1 | 633 | #define SAVED_CMDLINES 128 |
2c7eea4c | 634 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
635 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
636 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
637 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
638 | static int cmdline_idx; | |
efed792d | 639 | static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; |
25b0b44a | 640 | |
25b0b44a | 641 | /* temporary disable recording */ |
4fd27358 | 642 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
643 | |
644 | static void trace_init_cmdlines(void) | |
645 | { | |
2c7eea4c TG |
646 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
647 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
648 | cmdline_idx = 0; |
649 | } | |
650 | ||
0f048701 SR |
651 | static int trace_stop_count; |
652 | static DEFINE_SPINLOCK(tracing_start_lock); | |
653 | ||
69bb54ec SR |
654 | /** |
655 | * ftrace_off_permanent - disable all ftrace code permanently | |
656 | * | |
657 | * This should only be called when a serious anomally has | |
658 | * been detected. This will turn off the function tracing, | |
659 | * ring buffers, and other tracing utilites. It takes no | |
660 | * locks and can be called from any context. | |
661 | */ | |
662 | void ftrace_off_permanent(void) | |
663 | { | |
664 | tracing_disabled = 1; | |
665 | ftrace_stop(); | |
666 | tracing_off_permanent(); | |
667 | } | |
668 | ||
0f048701 SR |
669 | /** |
670 | * tracing_start - quick start of the tracer | |
671 | * | |
672 | * If tracing is enabled but was stopped by tracing_stop, | |
673 | * this will start the tracer back up. | |
674 | */ | |
675 | void tracing_start(void) | |
676 | { | |
677 | struct ring_buffer *buffer; | |
678 | unsigned long flags; | |
679 | ||
680 | if (tracing_disabled) | |
681 | return; | |
682 | ||
683 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
684 | if (--trace_stop_count) { |
685 | if (trace_stop_count < 0) { | |
686 | /* Someone screwed up their debugging */ | |
687 | WARN_ON_ONCE(1); | |
688 | trace_stop_count = 0; | |
689 | } | |
0f048701 SR |
690 | goto out; |
691 | } | |
692 | ||
693 | ||
694 | buffer = global_trace.buffer; | |
695 | if (buffer) | |
696 | ring_buffer_record_enable(buffer); | |
697 | ||
698 | buffer = max_tr.buffer; | |
699 | if (buffer) | |
700 | ring_buffer_record_enable(buffer); | |
701 | ||
702 | ftrace_start(); | |
703 | out: | |
704 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
705 | } | |
706 | ||
707 | /** | |
708 | * tracing_stop - quick stop of the tracer | |
709 | * | |
710 | * Light weight way to stop tracing. Use in conjunction with | |
711 | * tracing_start. | |
712 | */ | |
713 | void tracing_stop(void) | |
714 | { | |
715 | struct ring_buffer *buffer; | |
716 | unsigned long flags; | |
717 | ||
718 | ftrace_stop(); | |
719 | spin_lock_irqsave(&tracing_start_lock, flags); | |
720 | if (trace_stop_count++) | |
721 | goto out; | |
722 | ||
723 | buffer = global_trace.buffer; | |
724 | if (buffer) | |
725 | ring_buffer_record_disable(buffer); | |
726 | ||
727 | buffer = max_tr.buffer; | |
728 | if (buffer) | |
729 | ring_buffer_record_disable(buffer); | |
730 | ||
731 | out: | |
732 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
733 | } | |
734 | ||
e309b41d | 735 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 736 | |
e309b41d | 737 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 738 | { |
a635cf04 | 739 | unsigned pid, idx; |
bc0c38d1 SR |
740 | |
741 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
742 | return; | |
743 | ||
744 | /* | |
745 | * It's not the end of the world if we don't get | |
746 | * the lock, but we also don't want to spin | |
747 | * nor do we want to disable interrupts, | |
748 | * so if we miss here, then better luck next time. | |
749 | */ | |
efed792d | 750 | if (!__raw_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
751 | return; |
752 | ||
753 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 754 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
755 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
756 | ||
a635cf04 CE |
757 | /* |
758 | * Check whether the cmdline buffer at idx has a pid | |
759 | * mapped. We are going to overwrite that entry so we | |
760 | * need to clear the map_pid_to_cmdline. Otherwise we | |
761 | * would read the new comm for the old pid. | |
762 | */ | |
763 | pid = map_cmdline_to_pid[idx]; | |
764 | if (pid != NO_CMDLINE_MAP) | |
765 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 766 | |
a635cf04 | 767 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
768 | map_pid_to_cmdline[tsk->pid] = idx; |
769 | ||
770 | cmdline_idx = idx; | |
771 | } | |
772 | ||
773 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
774 | ||
efed792d | 775 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
776 | } |
777 | ||
4ca53085 | 778 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 779 | { |
bc0c38d1 SR |
780 | unsigned map; |
781 | ||
4ca53085 SR |
782 | if (!pid) { |
783 | strcpy(comm, "<idle>"); | |
784 | return; | |
785 | } | |
bc0c38d1 | 786 | |
4ca53085 SR |
787 | if (pid > PID_MAX_DEFAULT) { |
788 | strcpy(comm, "<...>"); | |
789 | return; | |
790 | } | |
bc0c38d1 | 791 | |
4ca53085 | 792 | __raw_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 793 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
794 | if (map != NO_CMDLINE_MAP) |
795 | strcpy(comm, saved_cmdlines[map]); | |
796 | else | |
797 | strcpy(comm, "<...>"); | |
bc0c38d1 | 798 | |
4ca53085 | 799 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
800 | } |
801 | ||
e309b41d | 802 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 803 | { |
18aecd36 TG |
804 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
805 | !tracing_is_on()) | |
bc0c38d1 SR |
806 | return; |
807 | ||
808 | trace_save_cmdline(tsk); | |
809 | } | |
810 | ||
45dcd8b8 | 811 | void |
38697053 SR |
812 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
813 | int pc) | |
bc0c38d1 SR |
814 | { |
815 | struct task_struct *tsk = current; | |
bc0c38d1 | 816 | |
777e208d SR |
817 | entry->preempt_count = pc & 0xff; |
818 | entry->pid = (tsk) ? tsk->pid : 0; | |
ef18012b | 819 | entry->tgid = (tsk) ? tsk->tgid : 0; |
777e208d | 820 | entry->flags = |
9244489a | 821 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 822 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
823 | #else |
824 | TRACE_FLAG_IRQS_NOSUPPORT | | |
825 | #endif | |
bc0c38d1 SR |
826 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
827 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
828 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
829 | } | |
830 | ||
51a763dd ACM |
831 | struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr, |
832 | unsigned char type, | |
833 | unsigned long len, | |
834 | unsigned long flags, int pc) | |
835 | { | |
836 | struct ring_buffer_event *event; | |
837 | ||
838 | event = ring_buffer_lock_reserve(tr->buffer, len); | |
839 | if (event != NULL) { | |
840 | struct trace_entry *ent = ring_buffer_event_data(event); | |
841 | ||
842 | tracing_generic_entry_update(ent, flags, pc); | |
843 | ent->type = type; | |
844 | } | |
845 | ||
846 | return event; | |
847 | } | |
848 | static void ftrace_trace_stack(struct trace_array *tr, | |
849 | unsigned long flags, int skip, int pc); | |
850 | static void ftrace_trace_userstack(struct trace_array *tr, | |
851 | unsigned long flags, int pc); | |
852 | ||
853 | void trace_buffer_unlock_commit(struct trace_array *tr, | |
854 | struct ring_buffer_event *event, | |
855 | unsigned long flags, int pc) | |
856 | { | |
857 | ring_buffer_unlock_commit(tr->buffer, event); | |
858 | ||
859 | ftrace_trace_stack(tr, flags, 6, pc); | |
860 | ftrace_trace_userstack(tr, flags, pc); | |
861 | trace_wake_up(); | |
862 | } | |
863 | ||
ef5580d0 SR |
864 | struct ring_buffer_event * |
865 | trace_current_buffer_lock_reserve(unsigned char type, unsigned long len, | |
866 | unsigned long flags, int pc) | |
867 | { | |
868 | return trace_buffer_lock_reserve(&global_trace, | |
869 | type, len, flags, pc); | |
870 | } | |
871 | ||
872 | void trace_current_buffer_unlock_commit(struct ring_buffer_event *event, | |
873 | unsigned long flags, int pc) | |
874 | { | |
875 | return trace_buffer_unlock_commit(&global_trace, event, flags, pc); | |
876 | } | |
877 | ||
e309b41d | 878 | void |
7be42151 | 879 | trace_function(struct trace_array *tr, |
38697053 SR |
880 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
881 | int pc) | |
bc0c38d1 | 882 | { |
3928a8a2 | 883 | struct ring_buffer_event *event; |
777e208d | 884 | struct ftrace_entry *entry; |
bc0c38d1 | 885 | |
d769041f SR |
886 | /* If we are reading the ring buffer, don't trace */ |
887 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
888 | return; | |
889 | ||
51a763dd ACM |
890 | event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry), |
891 | flags, pc); | |
3928a8a2 SR |
892 | if (!event) |
893 | return; | |
894 | entry = ring_buffer_event_data(event); | |
777e208d SR |
895 | entry->ip = ip; |
896 | entry->parent_ip = parent_ip; | |
0a987751 | 897 | ring_buffer_unlock_commit(tr->buffer, event); |
bc0c38d1 SR |
898 | } |
899 | ||
fb52607a | 900 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
287b6e68 | 901 | static void __trace_graph_entry(struct trace_array *tr, |
287b6e68 FW |
902 | struct ftrace_graph_ent *trace, |
903 | unsigned long flags, | |
904 | int pc) | |
905 | { | |
906 | struct ring_buffer_event *event; | |
907 | struct ftrace_graph_ent_entry *entry; | |
287b6e68 FW |
908 | |
909 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
910 | return; | |
911 | ||
51a763dd ACM |
912 | event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_ENT, |
913 | sizeof(*entry), flags, pc); | |
287b6e68 FW |
914 | if (!event) |
915 | return; | |
916 | entry = ring_buffer_event_data(event); | |
287b6e68 | 917 | entry->graph_ent = *trace; |
0a987751 | 918 | ring_buffer_unlock_commit(global_trace.buffer, event); |
287b6e68 FW |
919 | } |
920 | ||
921 | static void __trace_graph_return(struct trace_array *tr, | |
fb52607a | 922 | struct ftrace_graph_ret *trace, |
15e6cb36 FW |
923 | unsigned long flags, |
924 | int pc) | |
925 | { | |
926 | struct ring_buffer_event *event; | |
287b6e68 | 927 | struct ftrace_graph_ret_entry *entry; |
15e6cb36 FW |
928 | |
929 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
930 | return; | |
931 | ||
51a763dd ACM |
932 | event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_RET, |
933 | sizeof(*entry), flags, pc); | |
15e6cb36 FW |
934 | if (!event) |
935 | return; | |
936 | entry = ring_buffer_event_data(event); | |
287b6e68 | 937 | entry->ret = *trace; |
0a987751 | 938 | ring_buffer_unlock_commit(global_trace.buffer, event); |
15e6cb36 FW |
939 | } |
940 | #endif | |
941 | ||
e309b41d | 942 | void |
2e0f5761 | 943 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
944 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
945 | int pc) | |
2e0f5761 IM |
946 | { |
947 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 948 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
949 | } |
950 | ||
53614991 | 951 | static void __ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
952 | unsigned long flags, |
953 | int skip, int pc) | |
86387f7e | 954 | { |
c2c80529 | 955 | #ifdef CONFIG_STACKTRACE |
3928a8a2 | 956 | struct ring_buffer_event *event; |
777e208d | 957 | struct stack_entry *entry; |
86387f7e IM |
958 | struct stack_trace trace; |
959 | ||
51a763dd ACM |
960 | event = trace_buffer_lock_reserve(tr, TRACE_STACK, |
961 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
962 | if (!event) |
963 | return; | |
964 | entry = ring_buffer_event_data(event); | |
777e208d | 965 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
966 | |
967 | trace.nr_entries = 0; | |
968 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
969 | trace.skip = skip; | |
777e208d | 970 | trace.entries = entry->caller; |
86387f7e IM |
971 | |
972 | save_stack_trace(&trace); | |
0a987751 | 973 | ring_buffer_unlock_commit(tr->buffer, event); |
c2c80529 | 974 | #endif |
f0a920d5 IM |
975 | } |
976 | ||
53614991 | 977 | static void ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
978 | unsigned long flags, |
979 | int skip, int pc) | |
980 | { | |
981 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
982 | return; | |
983 | ||
7be42151 | 984 | __ftrace_trace_stack(tr, flags, skip, pc); |
53614991 SR |
985 | } |
986 | ||
38697053 | 987 | void __trace_stack(struct trace_array *tr, |
38697053 | 988 | unsigned long flags, |
53614991 | 989 | int skip, int pc) |
38697053 | 990 | { |
7be42151 | 991 | __ftrace_trace_stack(tr, flags, skip, pc); |
38697053 SR |
992 | } |
993 | ||
02b67518 | 994 | static void ftrace_trace_userstack(struct trace_array *tr, |
7be42151 | 995 | unsigned long flags, int pc) |
02b67518 | 996 | { |
c7425acb | 997 | #ifdef CONFIG_STACKTRACE |
8d7c6a96 | 998 | struct ring_buffer_event *event; |
02b67518 TE |
999 | struct userstack_entry *entry; |
1000 | struct stack_trace trace; | |
02b67518 TE |
1001 | |
1002 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1003 | return; | |
1004 | ||
51a763dd ACM |
1005 | event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK, |
1006 | sizeof(*entry), flags, pc); | |
02b67518 TE |
1007 | if (!event) |
1008 | return; | |
1009 | entry = ring_buffer_event_data(event); | |
02b67518 TE |
1010 | |
1011 | memset(&entry->caller, 0, sizeof(entry->caller)); | |
1012 | ||
1013 | trace.nr_entries = 0; | |
1014 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1015 | trace.skip = 0; | |
1016 | trace.entries = entry->caller; | |
1017 | ||
1018 | save_stack_trace_user(&trace); | |
0a987751 | 1019 | ring_buffer_unlock_commit(tr->buffer, event); |
c7425acb | 1020 | #endif |
02b67518 TE |
1021 | } |
1022 | ||
4fd27358 HE |
1023 | #ifdef UNUSED |
1024 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1025 | { |
7be42151 | 1026 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1027 | } |
4fd27358 | 1028 | #endif /* UNUSED */ |
02b67518 | 1029 | |
38697053 | 1030 | static void |
7be42151 | 1031 | ftrace_trace_special(void *__tr, |
38697053 SR |
1032 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1033 | int pc) | |
a4feb834 | 1034 | { |
3928a8a2 | 1035 | struct ring_buffer_event *event; |
a4feb834 | 1036 | struct trace_array *tr = __tr; |
777e208d | 1037 | struct special_entry *entry; |
a4feb834 | 1038 | |
51a763dd ACM |
1039 | event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL, |
1040 | sizeof(*entry), 0, pc); | |
3928a8a2 SR |
1041 | if (!event) |
1042 | return; | |
1043 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1044 | entry->arg1 = arg1; |
1045 | entry->arg2 = arg2; | |
1046 | entry->arg3 = arg3; | |
51a763dd | 1047 | trace_buffer_unlock_commit(tr, event, 0, pc); |
a4feb834 IM |
1048 | } |
1049 | ||
38697053 SR |
1050 | void |
1051 | __trace_special(void *__tr, void *__data, | |
1052 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1053 | { | |
7be42151 | 1054 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1055 | } |
1056 | ||
e309b41d | 1057 | void |
bc0c38d1 | 1058 | tracing_sched_switch_trace(struct trace_array *tr, |
86387f7e IM |
1059 | struct task_struct *prev, |
1060 | struct task_struct *next, | |
38697053 | 1061 | unsigned long flags, int pc) |
bc0c38d1 | 1062 | { |
3928a8a2 | 1063 | struct ring_buffer_event *event; |
777e208d | 1064 | struct ctx_switch_entry *entry; |
bc0c38d1 | 1065 | |
51a763dd ACM |
1066 | event = trace_buffer_lock_reserve(tr, TRACE_CTX, |
1067 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1068 | if (!event) |
1069 | return; | |
1070 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1071 | entry->prev_pid = prev->pid; |
1072 | entry->prev_prio = prev->prio; | |
1073 | entry->prev_state = prev->state; | |
1074 | entry->next_pid = next->pid; | |
1075 | entry->next_prio = next->prio; | |
1076 | entry->next_state = next->state; | |
1077 | entry->next_cpu = task_cpu(next); | |
51a763dd | 1078 | trace_buffer_unlock_commit(tr, event, flags, pc); |
bc0c38d1 SR |
1079 | } |
1080 | ||
57422797 IM |
1081 | void |
1082 | tracing_sched_wakeup_trace(struct trace_array *tr, | |
86387f7e IM |
1083 | struct task_struct *wakee, |
1084 | struct task_struct *curr, | |
38697053 | 1085 | unsigned long flags, int pc) |
57422797 | 1086 | { |
3928a8a2 | 1087 | struct ring_buffer_event *event; |
777e208d | 1088 | struct ctx_switch_entry *entry; |
57422797 | 1089 | |
51a763dd ACM |
1090 | event = trace_buffer_lock_reserve(tr, TRACE_WAKE, |
1091 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1092 | if (!event) |
1093 | return; | |
1094 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1095 | entry->prev_pid = curr->pid; |
1096 | entry->prev_prio = curr->prio; | |
1097 | entry->prev_state = curr->state; | |
1098 | entry->next_pid = wakee->pid; | |
1099 | entry->next_prio = wakee->prio; | |
1100 | entry->next_state = wakee->state; | |
1101 | entry->next_cpu = task_cpu(wakee); | |
6eaaa5d5 FW |
1102 | |
1103 | ring_buffer_unlock_commit(tr->buffer, event); | |
1104 | ftrace_trace_stack(tr, flags, 6, pc); | |
1105 | ftrace_trace_userstack(tr, flags, pc); | |
57422797 IM |
1106 | } |
1107 | ||
4902f884 SR |
1108 | void |
1109 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1110 | { | |
1111 | struct trace_array *tr = &global_trace; | |
1112 | struct trace_array_cpu *data; | |
5aa1ba6a | 1113 | unsigned long flags; |
4902f884 | 1114 | int cpu; |
38697053 | 1115 | int pc; |
4902f884 | 1116 | |
c76f0694 | 1117 | if (tracing_disabled) |
4902f884 SR |
1118 | return; |
1119 | ||
38697053 | 1120 | pc = preempt_count(); |
5aa1ba6a | 1121 | local_irq_save(flags); |
4902f884 SR |
1122 | cpu = raw_smp_processor_id(); |
1123 | data = tr->data[cpu]; | |
4902f884 | 1124 | |
5aa1ba6a | 1125 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1126 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1127 | |
5aa1ba6a SR |
1128 | atomic_dec(&data->disabled); |
1129 | local_irq_restore(flags); | |
4902f884 SR |
1130 | } |
1131 | ||
fb52607a | 1132 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e49dc19c | 1133 | int trace_graph_entry(struct ftrace_graph_ent *trace) |
15e6cb36 FW |
1134 | { |
1135 | struct trace_array *tr = &global_trace; | |
1136 | struct trace_array_cpu *data; | |
1137 | unsigned long flags; | |
1138 | long disabled; | |
1139 | int cpu; | |
1140 | int pc; | |
1141 | ||
804a6851 SR |
1142 | if (!ftrace_trace_task(current)) |
1143 | return 0; | |
1144 | ||
ea4e2bc4 SR |
1145 | if (!ftrace_graph_addr(trace->func)) |
1146 | return 0; | |
1147 | ||
a5e25883 | 1148 | local_irq_save(flags); |
15e6cb36 FW |
1149 | cpu = raw_smp_processor_id(); |
1150 | data = tr->data[cpu]; | |
1151 | disabled = atomic_inc_return(&data->disabled); | |
1152 | if (likely(disabled == 1)) { | |
1153 | pc = preempt_count(); | |
7be42151 | 1154 | __trace_graph_entry(tr, trace, flags, pc); |
287b6e68 | 1155 | } |
ea4e2bc4 SR |
1156 | /* Only do the atomic if it is not already set */ |
1157 | if (!test_tsk_trace_graph(current)) | |
1158 | set_tsk_trace_graph(current); | |
287b6e68 | 1159 | atomic_dec(&data->disabled); |
a5e25883 | 1160 | local_irq_restore(flags); |
e49dc19c SR |
1161 | |
1162 | return 1; | |
287b6e68 FW |
1163 | } |
1164 | ||
1165 | void trace_graph_return(struct ftrace_graph_ret *trace) | |
1166 | { | |
1167 | struct trace_array *tr = &global_trace; | |
1168 | struct trace_array_cpu *data; | |
1169 | unsigned long flags; | |
1170 | long disabled; | |
1171 | int cpu; | |
1172 | int pc; | |
1173 | ||
a5e25883 | 1174 | local_irq_save(flags); |
287b6e68 FW |
1175 | cpu = raw_smp_processor_id(); |
1176 | data = tr->data[cpu]; | |
1177 | disabled = atomic_inc_return(&data->disabled); | |
1178 | if (likely(disabled == 1)) { | |
1179 | pc = preempt_count(); | |
7be42151 | 1180 | __trace_graph_return(tr, trace, flags, pc); |
15e6cb36 | 1181 | } |
ea4e2bc4 SR |
1182 | if (!trace->depth) |
1183 | clear_tsk_trace_graph(current); | |
15e6cb36 | 1184 | atomic_dec(&data->disabled); |
a5e25883 | 1185 | local_irq_restore(flags); |
15e6cb36 | 1186 | } |
fb52607a | 1187 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
15e6cb36 | 1188 | |
769b0441 FW |
1189 | |
1190 | /** | |
48ead020 | 1191 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1192 | * |
1193 | */ | |
40ce74f1 | 1194 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1195 | { |
80370cb7 SR |
1196 | static raw_spinlock_t trace_buf_lock = |
1197 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
769b0441 FW |
1198 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1199 | ||
1200 | struct ring_buffer_event *event; | |
1201 | struct trace_array *tr = &global_trace; | |
1202 | struct trace_array_cpu *data; | |
48ead020 | 1203 | struct bprint_entry *entry; |
769b0441 FW |
1204 | unsigned long flags; |
1205 | int resched; | |
1206 | int cpu, len = 0, size, pc; | |
1207 | ||
1208 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1209 | return 0; | |
1210 | ||
1211 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1212 | pause_graph_tracing(); | |
1213 | ||
1214 | pc = preempt_count(); | |
1215 | resched = ftrace_preempt_disable(); | |
1216 | cpu = raw_smp_processor_id(); | |
1217 | data = tr->data[cpu]; | |
1218 | ||
1219 | if (unlikely(atomic_read(&data->disabled))) | |
1220 | goto out; | |
1221 | ||
80370cb7 SR |
1222 | /* Lockdep uses trace_printk for lock tracing */ |
1223 | local_irq_save(flags); | |
1224 | __raw_spin_lock(&trace_buf_lock); | |
769b0441 FW |
1225 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1226 | ||
1227 | if (len > TRACE_BUF_SIZE || len < 0) | |
1228 | goto out_unlock; | |
1229 | ||
1230 | size = sizeof(*entry) + sizeof(u32) * len; | |
48ead020 | 1231 | event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc); |
769b0441 FW |
1232 | if (!event) |
1233 | goto out_unlock; | |
1234 | entry = ring_buffer_event_data(event); | |
1235 | entry->ip = ip; | |
769b0441 FW |
1236 | entry->fmt = fmt; |
1237 | ||
1238 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
1239 | ring_buffer_unlock_commit(tr->buffer, event); | |
1240 | ||
1241 | out_unlock: | |
80370cb7 SR |
1242 | __raw_spin_unlock(&trace_buf_lock); |
1243 | local_irq_restore(flags); | |
769b0441 FW |
1244 | |
1245 | out: | |
1246 | ftrace_preempt_enable(resched); | |
1247 | unpause_graph_tracing(); | |
1248 | ||
1249 | return len; | |
1250 | } | |
48ead020 FW |
1251 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1252 | ||
40ce74f1 | 1253 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
48ead020 FW |
1254 | { |
1255 | static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; | |
1256 | static char trace_buf[TRACE_BUF_SIZE]; | |
1257 | ||
1258 | struct ring_buffer_event *event; | |
1259 | struct trace_array *tr = &global_trace; | |
1260 | struct trace_array_cpu *data; | |
1261 | int cpu, len = 0, size, pc; | |
1262 | struct print_entry *entry; | |
1263 | unsigned long irq_flags; | |
1264 | ||
1265 | if (tracing_disabled || tracing_selftest_running) | |
1266 | return 0; | |
1267 | ||
1268 | pc = preempt_count(); | |
1269 | preempt_disable_notrace(); | |
1270 | cpu = raw_smp_processor_id(); | |
1271 | data = tr->data[cpu]; | |
1272 | ||
1273 | if (unlikely(atomic_read(&data->disabled))) | |
1274 | goto out; | |
1275 | ||
1276 | pause_graph_tracing(); | |
1277 | raw_local_irq_save(irq_flags); | |
1278 | __raw_spin_lock(&trace_buf_lock); | |
1279 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); | |
1280 | ||
1281 | len = min(len, TRACE_BUF_SIZE-1); | |
1282 | trace_buf[len] = 0; | |
1283 | ||
1284 | size = sizeof(*entry) + len + 1; | |
1285 | event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc); | |
1286 | if (!event) | |
1287 | goto out_unlock; | |
1288 | entry = ring_buffer_event_data(event); | |
1289 | entry->ip = ip; | |
48ead020 FW |
1290 | |
1291 | memcpy(&entry->buf, trace_buf, len); | |
1292 | entry->buf[len] = 0; | |
1293 | ring_buffer_unlock_commit(tr->buffer, event); | |
1294 | ||
1295 | out_unlock: | |
1296 | __raw_spin_unlock(&trace_buf_lock); | |
1297 | raw_local_irq_restore(irq_flags); | |
1298 | unpause_graph_tracing(); | |
1299 | out: | |
1300 | preempt_enable_notrace(); | |
1301 | ||
1302 | return len; | |
1303 | } | |
769b0441 FW |
1304 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1305 | ||
bc0c38d1 SR |
1306 | enum trace_file_type { |
1307 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1308 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1309 | }; |
1310 | ||
e2ac8ef5 | 1311 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1312 | { |
d769041f SR |
1313 | /* Don't allow ftrace to trace into the ring buffers */ |
1314 | ftrace_disable_cpu(); | |
1315 | ||
5a90f577 | 1316 | iter->idx++; |
d769041f SR |
1317 | if (iter->buffer_iter[iter->cpu]) |
1318 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1319 | ||
1320 | ftrace_enable_cpu(); | |
5a90f577 SR |
1321 | } |
1322 | ||
e309b41d | 1323 | static struct trace_entry * |
3928a8a2 | 1324 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1325 | { |
3928a8a2 SR |
1326 | struct ring_buffer_event *event; |
1327 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1328 | |
d769041f SR |
1329 | /* Don't allow ftrace to trace into the ring buffers */ |
1330 | ftrace_disable_cpu(); | |
1331 | ||
1332 | if (buf_iter) | |
1333 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1334 | else | |
1335 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1336 | ||
1337 | ftrace_enable_cpu(); | |
1338 | ||
3928a8a2 | 1339 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1340 | } |
d769041f | 1341 | |
dd0e545f | 1342 | static struct trace_entry * |
3928a8a2 | 1343 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1344 | { |
3928a8a2 | 1345 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1346 | struct trace_entry *ent, *next = NULL; |
b04cc6b1 | 1347 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1348 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1349 | int next_cpu = -1; |
1350 | int cpu; | |
1351 | ||
b04cc6b1 FW |
1352 | /* |
1353 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1354 | * all cpu and peek directly. | |
1355 | */ | |
1356 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1357 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1358 | return NULL; | |
1359 | ent = peek_next_entry(iter, cpu_file, ent_ts); | |
1360 | if (ent_cpu) | |
1361 | *ent_cpu = cpu_file; | |
1362 | ||
1363 | return ent; | |
1364 | } | |
1365 | ||
ab46428c | 1366 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1367 | |
3928a8a2 SR |
1368 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1369 | continue; | |
dd0e545f | 1370 | |
3928a8a2 | 1371 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1372 | |
cdd31cd2 IM |
1373 | /* |
1374 | * Pick the entry with the smallest timestamp: | |
1375 | */ | |
3928a8a2 | 1376 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1377 | next = ent; |
1378 | next_cpu = cpu; | |
3928a8a2 | 1379 | next_ts = ts; |
bc0c38d1 SR |
1380 | } |
1381 | } | |
1382 | ||
1383 | if (ent_cpu) | |
1384 | *ent_cpu = next_cpu; | |
1385 | ||
3928a8a2 SR |
1386 | if (ent_ts) |
1387 | *ent_ts = next_ts; | |
1388 | ||
bc0c38d1 SR |
1389 | return next; |
1390 | } | |
1391 | ||
dd0e545f | 1392 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1393 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1394 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1395 | { |
3928a8a2 | 1396 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1397 | } |
1398 | ||
1399 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1400 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1401 | { | |
3928a8a2 | 1402 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1403 | |
3928a8a2 | 1404 | if (iter->ent) |
e2ac8ef5 | 1405 | trace_iterator_increment(iter); |
dd0e545f | 1406 | |
3928a8a2 | 1407 | return iter->ent ? iter : NULL; |
b3806b43 | 1408 | } |
bc0c38d1 | 1409 | |
e309b41d | 1410 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1411 | { |
d769041f SR |
1412 | /* Don't allow ftrace to trace into the ring buffers */ |
1413 | ftrace_disable_cpu(); | |
3928a8a2 | 1414 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1415 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1416 | } |
1417 | ||
e309b41d | 1418 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1419 | { |
1420 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1421 | int i = (int)*pos; |
4e3c3333 | 1422 | void *ent; |
bc0c38d1 SR |
1423 | |
1424 | (*pos)++; | |
1425 | ||
1426 | /* can't go backwards */ | |
1427 | if (iter->idx > i) | |
1428 | return NULL; | |
1429 | ||
1430 | if (iter->idx < 0) | |
1431 | ent = find_next_entry_inc(iter); | |
1432 | else | |
1433 | ent = iter; | |
1434 | ||
1435 | while (ent && iter->idx < i) | |
1436 | ent = find_next_entry_inc(iter); | |
1437 | ||
1438 | iter->pos = *pos; | |
1439 | ||
bc0c38d1 SR |
1440 | return ent; |
1441 | } | |
1442 | ||
d7350c3f FW |
1443 | /* |
1444 | * No necessary locking here. The worst thing which can | |
1445 | * happen is loosing events consumed at the same time | |
1446 | * by a trace_pipe reader. | |
1447 | * Other than that, we don't risk to crash the ring buffer | |
1448 | * because it serializes the readers. | |
1449 | * | |
1450 | * The current tracer is copied to avoid a global locking | |
1451 | * all around. | |
1452 | */ | |
bc0c38d1 SR |
1453 | static void *s_start(struct seq_file *m, loff_t *pos) |
1454 | { | |
1455 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1456 | static struct tracer *old_tracer; |
b04cc6b1 | 1457 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1458 | void *p = NULL; |
1459 | loff_t l = 0; | |
3928a8a2 | 1460 | int cpu; |
bc0c38d1 | 1461 | |
d7350c3f | 1462 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1463 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1464 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1465 | old_tracer = current_trace; | |
1466 | *iter->trace = *current_trace; | |
d15f57f2 | 1467 | } |
d7350c3f | 1468 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1469 | |
1470 | atomic_inc(&trace_record_cmdline_disabled); | |
1471 | ||
bc0c38d1 SR |
1472 | if (*pos != iter->pos) { |
1473 | iter->ent = NULL; | |
1474 | iter->cpu = 0; | |
1475 | iter->idx = -1; | |
1476 | ||
d769041f SR |
1477 | ftrace_disable_cpu(); |
1478 | ||
b04cc6b1 FW |
1479 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1480 | for_each_tracing_cpu(cpu) | |
1481 | ring_buffer_iter_reset(iter->buffer_iter[cpu]); | |
1482 | } else | |
1483 | ring_buffer_iter_reset(iter->buffer_iter[cpu_file]); | |
1484 | ||
bc0c38d1 | 1485 | |
d769041f SR |
1486 | ftrace_enable_cpu(); |
1487 | ||
bc0c38d1 SR |
1488 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1489 | ; | |
1490 | ||
1491 | } else { | |
4c11d7ae | 1492 | l = *pos - 1; |
bc0c38d1 SR |
1493 | p = s_next(m, p, &l); |
1494 | } | |
1495 | ||
1496 | return p; | |
1497 | } | |
1498 | ||
1499 | static void s_stop(struct seq_file *m, void *p) | |
1500 | { | |
bc0c38d1 | 1501 | atomic_dec(&trace_record_cmdline_disabled); |
bc0c38d1 SR |
1502 | } |
1503 | ||
e309b41d | 1504 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1505 | { |
a6168353 ME |
1506 | seq_puts(m, "# _------=> CPU# \n"); |
1507 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1508 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1509 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1510 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1511 | seq_puts(m, "# |||| / \n"); | |
1512 | seq_puts(m, "# ||||| delay \n"); | |
1513 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1514 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1515 | } |
1516 | ||
e309b41d | 1517 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1518 | { |
a6168353 ME |
1519 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1520 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1521 | } |
1522 | ||
1523 | ||
e309b41d | 1524 | static void |
bc0c38d1 SR |
1525 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1526 | { | |
1527 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1528 | struct trace_array *tr = iter->tr; | |
1529 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1530 | struct tracer *type = current_trace; | |
3928a8a2 SR |
1531 | unsigned long total; |
1532 | unsigned long entries; | |
bc0c38d1 SR |
1533 | const char *name = "preemption"; |
1534 | ||
1535 | if (type) | |
1536 | name = type->name; | |
1537 | ||
3928a8a2 SR |
1538 | entries = ring_buffer_entries(iter->tr->buffer); |
1539 | total = entries + | |
1540 | ring_buffer_overruns(iter->tr->buffer); | |
bc0c38d1 | 1541 | |
888b55dc | 1542 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1543 | name, UTS_RELEASE); |
888b55dc | 1544 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1545 | "---------------------------------\n"); |
888b55dc | 1546 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1547 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1548 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1549 | entries, |
4c11d7ae | 1550 | total, |
bc0c38d1 SR |
1551 | tr->cpu, |
1552 | #if defined(CONFIG_PREEMPT_NONE) | |
1553 | "server", | |
1554 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1555 | "desktop", | |
b5c21b45 | 1556 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1557 | "preempt", |
1558 | #else | |
1559 | "unknown", | |
1560 | #endif | |
1561 | /* These are reserved for later use */ | |
1562 | 0, 0, 0, 0); | |
1563 | #ifdef CONFIG_SMP | |
1564 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1565 | #else | |
1566 | seq_puts(m, ")\n"); | |
1567 | #endif | |
888b55dc KM |
1568 | seq_puts(m, "# -----------------\n"); |
1569 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1570 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1571 | data->comm, data->pid, data->uid, data->nice, | |
1572 | data->policy, data->rt_priority); | |
888b55dc | 1573 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1574 | |
1575 | if (data->critical_start) { | |
888b55dc | 1576 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1577 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1578 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1579 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1580 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1581 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1582 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1583 | } |
1584 | ||
888b55dc | 1585 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1586 | } |
1587 | ||
a309720c SR |
1588 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1589 | { | |
1590 | struct trace_seq *s = &iter->seq; | |
1591 | ||
12ef7d44 SR |
1592 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1593 | return; | |
1594 | ||
1595 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1596 | return; | |
1597 | ||
4462344e | 1598 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1599 | return; |
1600 | ||
4462344e | 1601 | cpumask_set_cpu(iter->cpu, iter->started); |
a309720c SR |
1602 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", iter->cpu); |
1603 | } | |
1604 | ||
2c4f035f | 1605 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1606 | { |
214023c3 | 1607 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1608 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1609 | struct trace_entry *entry; |
f633cef0 | 1610 | struct trace_event *event; |
bc0c38d1 | 1611 | |
4e3c3333 | 1612 | entry = iter->ent; |
dd0e545f | 1613 | |
a309720c SR |
1614 | test_cpu_buff_start(iter); |
1615 | ||
c4a8e8be | 1616 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1617 | |
c4a8e8be | 1618 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1619 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1620 | if (!trace_print_lat_context(iter)) | |
1621 | goto partial; | |
1622 | } else { | |
1623 | if (!trace_print_context(iter)) | |
1624 | goto partial; | |
1625 | } | |
c4a8e8be | 1626 | } |
bc0c38d1 | 1627 | |
268ccda0 | 1628 | if (event) |
d9793bd8 ACM |
1629 | return event->trace(iter, sym_flags); |
1630 | ||
1631 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1632 | goto partial; | |
02b67518 | 1633 | |
2c4f035f | 1634 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1635 | partial: |
1636 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1637 | } |
1638 | ||
2c4f035f | 1639 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1640 | { |
1641 | struct trace_seq *s = &iter->seq; | |
1642 | struct trace_entry *entry; | |
f633cef0 | 1643 | struct trace_event *event; |
f9896bf3 IM |
1644 | |
1645 | entry = iter->ent; | |
dd0e545f | 1646 | |
c4a8e8be | 1647 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1648 | if (!trace_seq_printf(s, "%d %d %llu ", |
1649 | entry->pid, iter->cpu, iter->ts)) | |
1650 | goto partial; | |
c4a8e8be | 1651 | } |
f9896bf3 | 1652 | |
f633cef0 | 1653 | event = ftrace_find_event(entry->type); |
268ccda0 | 1654 | if (event) |
d9793bd8 ACM |
1655 | return event->raw(iter, 0); |
1656 | ||
1657 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1658 | goto partial; | |
777e208d | 1659 | |
2c4f035f | 1660 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1661 | partial: |
1662 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1663 | } |
1664 | ||
2c4f035f | 1665 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1666 | { |
1667 | struct trace_seq *s = &iter->seq; | |
1668 | unsigned char newline = '\n'; | |
1669 | struct trace_entry *entry; | |
f633cef0 | 1670 | struct trace_event *event; |
5e3ca0ec IM |
1671 | |
1672 | entry = iter->ent; | |
dd0e545f | 1673 | |
c4a8e8be FW |
1674 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1675 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1676 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1677 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1678 | } | |
5e3ca0ec | 1679 | |
f633cef0 | 1680 | event = ftrace_find_event(entry->type); |
268ccda0 | 1681 | if (event) { |
ae7462b4 | 1682 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1683 | if (ret != TRACE_TYPE_HANDLED) |
1684 | return ret; | |
1685 | } | |
7104f300 | 1686 | |
5e3ca0ec IM |
1687 | SEQ_PUT_FIELD_RET(s, newline); |
1688 | ||
2c4f035f | 1689 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1690 | } |
1691 | ||
2c4f035f | 1692 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1693 | { |
1694 | struct trace_seq *s = &iter->seq; | |
1695 | struct trace_entry *entry; | |
f633cef0 | 1696 | struct trace_event *event; |
cb0f12aa IM |
1697 | |
1698 | entry = iter->ent; | |
dd0e545f | 1699 | |
c4a8e8be FW |
1700 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1701 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1702 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1703 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1704 | } | |
cb0f12aa | 1705 | |
f633cef0 | 1706 | event = ftrace_find_event(entry->type); |
268ccda0 | 1707 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1708 | } |
1709 | ||
bc0c38d1 SR |
1710 | static int trace_empty(struct trace_iterator *iter) |
1711 | { | |
bc0c38d1 SR |
1712 | int cpu; |
1713 | ||
9aba60fe SR |
1714 | /* If we are looking at one CPU buffer, only check that one */ |
1715 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1716 | cpu = iter->cpu_file; | |
1717 | if (iter->buffer_iter[cpu]) { | |
1718 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1719 | return 0; | |
1720 | } else { | |
1721 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1722 | return 0; | |
1723 | } | |
1724 | return 1; | |
1725 | } | |
1726 | ||
ab46428c | 1727 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1728 | if (iter->buffer_iter[cpu]) { |
1729 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1730 | return 0; | |
1731 | } else { | |
1732 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1733 | return 0; | |
1734 | } | |
bc0c38d1 | 1735 | } |
d769041f | 1736 | |
797d3712 | 1737 | return 1; |
bc0c38d1 SR |
1738 | } |
1739 | ||
2c4f035f | 1740 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1741 | { |
2c4f035f FW |
1742 | enum print_line_t ret; |
1743 | ||
1744 | if (iter->trace && iter->trace->print_line) { | |
1745 | ret = iter->trace->print_line(iter); | |
1746 | if (ret != TRACE_TYPE_UNHANDLED) | |
1747 | return ret; | |
1748 | } | |
72829bc3 | 1749 | |
48ead020 FW |
1750 | if (iter->ent->type == TRACE_BPRINT && |
1751 | trace_flags & TRACE_ITER_PRINTK && | |
1752 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1753 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 1754 | |
66896a85 FW |
1755 | if (iter->ent->type == TRACE_PRINT && |
1756 | trace_flags & TRACE_ITER_PRINTK && | |
1757 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1758 | return trace_print_printk_msg_only(iter); |
66896a85 | 1759 | |
cb0f12aa IM |
1760 | if (trace_flags & TRACE_ITER_BIN) |
1761 | return print_bin_fmt(iter); | |
1762 | ||
5e3ca0ec IM |
1763 | if (trace_flags & TRACE_ITER_HEX) |
1764 | return print_hex_fmt(iter); | |
1765 | ||
f9896bf3 IM |
1766 | if (trace_flags & TRACE_ITER_RAW) |
1767 | return print_raw_fmt(iter); | |
1768 | ||
f9896bf3 IM |
1769 | return print_trace_fmt(iter); |
1770 | } | |
1771 | ||
bc0c38d1 SR |
1772 | static int s_show(struct seq_file *m, void *v) |
1773 | { | |
1774 | struct trace_iterator *iter = v; | |
1775 | ||
1776 | if (iter->ent == NULL) { | |
1777 | if (iter->tr) { | |
1778 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1779 | seq_puts(m, "#\n"); | |
1780 | } | |
8bba1bf5 MM |
1781 | if (iter->trace && iter->trace->print_header) |
1782 | iter->trace->print_header(m); | |
1783 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
1784 | /* print nothing if the buffers are empty */ |
1785 | if (trace_empty(iter)) | |
1786 | return 0; | |
1787 | print_trace_header(m, iter); | |
1788 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1789 | print_lat_help_header(m); | |
1790 | } else { | |
1791 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1792 | print_func_help_header(m); | |
1793 | } | |
1794 | } else { | |
f9896bf3 | 1795 | print_trace_line(iter); |
214023c3 | 1796 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1797 | } |
1798 | ||
1799 | return 0; | |
1800 | } | |
1801 | ||
1802 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1803 | .start = s_start, |
1804 | .next = s_next, | |
1805 | .stop = s_stop, | |
1806 | .show = s_show, | |
bc0c38d1 SR |
1807 | }; |
1808 | ||
e309b41d | 1809 | static struct trace_iterator * |
85a2f9b4 | 1810 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 1811 | { |
b04cc6b1 | 1812 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 1813 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 1814 | struct trace_iterator *iter; |
3928a8a2 | 1815 | struct seq_file *m; |
85a2f9b4 | 1816 | int cpu, ret; |
bc0c38d1 | 1817 | |
85a2f9b4 SR |
1818 | if (tracing_disabled) |
1819 | return ERR_PTR(-ENODEV); | |
60a11774 | 1820 | |
bc0c38d1 | 1821 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
1822 | if (!iter) |
1823 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 1824 | |
d7350c3f FW |
1825 | /* |
1826 | * We make a copy of the current tracer to avoid concurrent | |
1827 | * changes on it while we are reading. | |
1828 | */ | |
bc0c38d1 | 1829 | mutex_lock(&trace_types_lock); |
d7350c3f | 1830 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 1831 | if (!iter->trace) |
d7350c3f | 1832 | goto fail; |
85a2f9b4 | 1833 | |
d7350c3f FW |
1834 | if (current_trace) |
1835 | *iter->trace = *current_trace; | |
1836 | ||
bc0c38d1 SR |
1837 | if (current_trace && current_trace->print_max) |
1838 | iter->tr = &max_tr; | |
1839 | else | |
b04cc6b1 | 1840 | iter->tr = &global_trace; |
bc0c38d1 | 1841 | iter->pos = -1; |
d7350c3f | 1842 | mutex_init(&iter->mutex); |
b04cc6b1 | 1843 | iter->cpu_file = cpu_file; |
bc0c38d1 | 1844 | |
8bba1bf5 MM |
1845 | /* Notify the tracer early; before we stop tracing. */ |
1846 | if (iter->trace && iter->trace->open) | |
a93751ca | 1847 | iter->trace->open(iter); |
8bba1bf5 | 1848 | |
12ef7d44 SR |
1849 | /* Annotate start of buffers if we had overruns */ |
1850 | if (ring_buffer_overruns(iter->tr->buffer)) | |
1851 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
1852 | ||
b04cc6b1 FW |
1853 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
1854 | for_each_tracing_cpu(cpu) { | |
12ef7d44 | 1855 | |
b04cc6b1 FW |
1856 | iter->buffer_iter[cpu] = |
1857 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
b04cc6b1 FW |
1858 | } |
1859 | } else { | |
1860 | cpu = iter->cpu_file; | |
3928a8a2 | 1861 | iter->buffer_iter[cpu] = |
b04cc6b1 | 1862 | ring_buffer_read_start(iter->tr->buffer, cpu); |
3928a8a2 SR |
1863 | } |
1864 | ||
bc0c38d1 | 1865 | /* TODO stop tracer */ |
85a2f9b4 SR |
1866 | ret = seq_open(file, &tracer_seq_ops); |
1867 | if (ret < 0) { | |
1868 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 1869 | goto fail_buffer; |
85a2f9b4 | 1870 | } |
bc0c38d1 | 1871 | |
3928a8a2 SR |
1872 | m = file->private_data; |
1873 | m->private = iter; | |
bc0c38d1 | 1874 | |
3928a8a2 | 1875 | /* stop the trace while dumping */ |
9036990d | 1876 | tracing_stop(); |
3928a8a2 | 1877 | |
bc0c38d1 SR |
1878 | mutex_unlock(&trace_types_lock); |
1879 | ||
bc0c38d1 | 1880 | return iter; |
3928a8a2 SR |
1881 | |
1882 | fail_buffer: | |
1883 | for_each_tracing_cpu(cpu) { | |
1884 | if (iter->buffer_iter[cpu]) | |
1885 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1886 | } | |
d7350c3f | 1887 | fail: |
3928a8a2 | 1888 | mutex_unlock(&trace_types_lock); |
d7350c3f | 1889 | kfree(iter->trace); |
0bb943c7 | 1890 | kfree(iter); |
3928a8a2 | 1891 | |
85a2f9b4 | 1892 | return fail_ret; |
bc0c38d1 SR |
1893 | } |
1894 | ||
1895 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1896 | { | |
60a11774 SR |
1897 | if (tracing_disabled) |
1898 | return -ENODEV; | |
1899 | ||
bc0c38d1 SR |
1900 | filp->private_data = inode->i_private; |
1901 | return 0; | |
1902 | } | |
1903 | ||
4fd27358 | 1904 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
1905 | { |
1906 | struct seq_file *m = (struct seq_file *)file->private_data; | |
4acd4d00 | 1907 | struct trace_iterator *iter; |
3928a8a2 | 1908 | int cpu; |
bc0c38d1 | 1909 | |
4acd4d00 SR |
1910 | if (!(file->f_mode & FMODE_READ)) |
1911 | return 0; | |
1912 | ||
1913 | iter = m->private; | |
1914 | ||
bc0c38d1 | 1915 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
1916 | for_each_tracing_cpu(cpu) { |
1917 | if (iter->buffer_iter[cpu]) | |
1918 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1919 | } | |
1920 | ||
bc0c38d1 SR |
1921 | if (iter->trace && iter->trace->close) |
1922 | iter->trace->close(iter); | |
1923 | ||
1924 | /* reenable tracing if it was previously enabled */ | |
9036990d | 1925 | tracing_start(); |
bc0c38d1 SR |
1926 | mutex_unlock(&trace_types_lock); |
1927 | ||
1928 | seq_release(inode, file); | |
d7350c3f FW |
1929 | mutex_destroy(&iter->mutex); |
1930 | kfree(iter->trace); | |
bc0c38d1 SR |
1931 | kfree(iter); |
1932 | return 0; | |
1933 | } | |
1934 | ||
1935 | static int tracing_open(struct inode *inode, struct file *file) | |
1936 | { | |
85a2f9b4 SR |
1937 | struct trace_iterator *iter; |
1938 | int ret = 0; | |
bc0c38d1 | 1939 | |
4acd4d00 SR |
1940 | /* If this file was open for write, then erase contents */ |
1941 | if ((file->f_mode & FMODE_WRITE) && | |
1942 | !(file->f_flags & O_APPEND)) { | |
1943 | long cpu = (long) inode->i_private; | |
bc0c38d1 | 1944 | |
4acd4d00 SR |
1945 | if (cpu == TRACE_PIPE_ALL_CPU) |
1946 | tracing_reset_online_cpus(&global_trace); | |
1947 | else | |
1948 | tracing_reset(&global_trace, cpu); | |
1949 | } | |
bc0c38d1 | 1950 | |
4acd4d00 SR |
1951 | if (file->f_mode & FMODE_READ) { |
1952 | iter = __tracing_open(inode, file); | |
1953 | if (IS_ERR(iter)) | |
1954 | ret = PTR_ERR(iter); | |
1955 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
1956 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
1957 | } | |
bc0c38d1 SR |
1958 | return ret; |
1959 | } | |
1960 | ||
e309b41d | 1961 | static void * |
bc0c38d1 SR |
1962 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1963 | { | |
1964 | struct tracer *t = m->private; | |
1965 | ||
1966 | (*pos)++; | |
1967 | ||
1968 | if (t) | |
1969 | t = t->next; | |
1970 | ||
1971 | m->private = t; | |
1972 | ||
1973 | return t; | |
1974 | } | |
1975 | ||
1976 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1977 | { | |
1978 | struct tracer *t = m->private; | |
1979 | loff_t l = 0; | |
1980 | ||
1981 | mutex_lock(&trace_types_lock); | |
1982 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
1983 | ; | |
1984 | ||
1985 | return t; | |
1986 | } | |
1987 | ||
1988 | static void t_stop(struct seq_file *m, void *p) | |
1989 | { | |
1990 | mutex_unlock(&trace_types_lock); | |
1991 | } | |
1992 | ||
1993 | static int t_show(struct seq_file *m, void *v) | |
1994 | { | |
1995 | struct tracer *t = v; | |
1996 | ||
1997 | if (!t) | |
1998 | return 0; | |
1999 | ||
2000 | seq_printf(m, "%s", t->name); | |
2001 | if (t->next) | |
2002 | seq_putc(m, ' '); | |
2003 | else | |
2004 | seq_putc(m, '\n'); | |
2005 | ||
2006 | return 0; | |
2007 | } | |
2008 | ||
2009 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
2010 | .start = t_start, |
2011 | .next = t_next, | |
2012 | .stop = t_stop, | |
2013 | .show = t_show, | |
bc0c38d1 SR |
2014 | }; |
2015 | ||
2016 | static int show_traces_open(struct inode *inode, struct file *file) | |
2017 | { | |
2018 | int ret; | |
2019 | ||
60a11774 SR |
2020 | if (tracing_disabled) |
2021 | return -ENODEV; | |
2022 | ||
bc0c38d1 SR |
2023 | ret = seq_open(file, &show_traces_seq_ops); |
2024 | if (!ret) { | |
2025 | struct seq_file *m = file->private_data; | |
2026 | m->private = trace_types; | |
2027 | } | |
2028 | ||
2029 | return ret; | |
2030 | } | |
2031 | ||
4acd4d00 SR |
2032 | static ssize_t |
2033 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2034 | size_t count, loff_t *ppos) | |
2035 | { | |
2036 | return count; | |
2037 | } | |
2038 | ||
5e2336a0 | 2039 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2040 | .open = tracing_open, |
2041 | .read = seq_read, | |
4acd4d00 | 2042 | .write = tracing_write_stub, |
4bf39a94 IM |
2043 | .llseek = seq_lseek, |
2044 | .release = tracing_release, | |
bc0c38d1 SR |
2045 | }; |
2046 | ||
5e2336a0 | 2047 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2048 | .open = show_traces_open, |
2049 | .read = seq_read, | |
2050 | .release = seq_release, | |
2051 | }; | |
2052 | ||
36dfe925 IM |
2053 | /* |
2054 | * Only trace on a CPU if the bitmask is set: | |
2055 | */ | |
9e01c1b7 | 2056 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2057 | |
2058 | /* | |
2059 | * The tracer itself will not take this lock, but still we want | |
2060 | * to provide a consistent cpumask to user-space: | |
2061 | */ | |
2062 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2063 | ||
2064 | /* | |
2065 | * Temporary storage for the character representation of the | |
2066 | * CPU bitmask (and one more byte for the newline): | |
2067 | */ | |
2068 | static char mask_str[NR_CPUS + 1]; | |
2069 | ||
c7078de1 IM |
2070 | static ssize_t |
2071 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2072 | size_t count, loff_t *ppos) | |
2073 | { | |
36dfe925 | 2074 | int len; |
c7078de1 IM |
2075 | |
2076 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2077 | |
9e01c1b7 | 2078 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2079 | if (count - len < 2) { |
2080 | count = -EINVAL; | |
2081 | goto out_err; | |
2082 | } | |
2083 | len += sprintf(mask_str + len, "\n"); | |
2084 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2085 | ||
2086 | out_err: | |
c7078de1 IM |
2087 | mutex_unlock(&tracing_cpumask_update_lock); |
2088 | ||
2089 | return count; | |
2090 | } | |
2091 | ||
2092 | static ssize_t | |
2093 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2094 | size_t count, loff_t *ppos) | |
2095 | { | |
36dfe925 | 2096 | int err, cpu; |
9e01c1b7 RR |
2097 | cpumask_var_t tracing_cpumask_new; |
2098 | ||
2099 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2100 | return -ENOMEM; | |
c7078de1 IM |
2101 | |
2102 | mutex_lock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2103 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2104 | if (err) |
36dfe925 IM |
2105 | goto err_unlock; |
2106 | ||
a5e25883 | 2107 | local_irq_disable(); |
92205c23 | 2108 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 2109 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2110 | /* |
2111 | * Increase/decrease the disabled counter if we are | |
2112 | * about to flip a bit in the cpumask: | |
2113 | */ | |
9e01c1b7 RR |
2114 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2115 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2116 | atomic_inc(&global_trace.data[cpu]->disabled); |
2117 | } | |
9e01c1b7 RR |
2118 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2119 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2120 | atomic_dec(&global_trace.data[cpu]->disabled); |
2121 | } | |
2122 | } | |
92205c23 | 2123 | __raw_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2124 | local_irq_enable(); |
36dfe925 | 2125 | |
9e01c1b7 | 2126 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2127 | |
2128 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2129 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2130 | |
2131 | return count; | |
36dfe925 IM |
2132 | |
2133 | err_unlock: | |
2134 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2135 | free_cpumask_var(tracing_cpumask); |
36dfe925 IM |
2136 | |
2137 | return err; | |
c7078de1 IM |
2138 | } |
2139 | ||
5e2336a0 | 2140 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2141 | .open = tracing_open_generic, |
2142 | .read = tracing_cpumask_read, | |
2143 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2144 | }; |
2145 | ||
2146 | static ssize_t | |
ee6bce52 | 2147 | tracing_trace_options_read(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
2148 | size_t cnt, loff_t *ppos) |
2149 | { | |
d8e83d26 SR |
2150 | struct tracer_opt *trace_opts; |
2151 | u32 tracer_flags; | |
2152 | int len = 0; | |
bc0c38d1 SR |
2153 | char *buf; |
2154 | int r = 0; | |
d8e83d26 | 2155 | int i; |
adf9f195 | 2156 | |
bc0c38d1 | 2157 | |
c3706f00 | 2158 | /* calculate max size */ |
bc0c38d1 SR |
2159 | for (i = 0; trace_options[i]; i++) { |
2160 | len += strlen(trace_options[i]); | |
5c6a3ae1 | 2161 | len += 3; /* "no" and newline */ |
bc0c38d1 SR |
2162 | } |
2163 | ||
d8e83d26 SR |
2164 | mutex_lock(&trace_types_lock); |
2165 | tracer_flags = current_trace->flags->val; | |
2166 | trace_opts = current_trace->flags->opts; | |
2167 | ||
adf9f195 FW |
2168 | /* |
2169 | * Increase the size with names of options specific | |
2170 | * of the current tracer. | |
2171 | */ | |
2172 | for (i = 0; trace_opts[i].name; i++) { | |
2173 | len += strlen(trace_opts[i].name); | |
5c6a3ae1 | 2174 | len += 3; /* "no" and newline */ |
adf9f195 FW |
2175 | } |
2176 | ||
bc0c38d1 SR |
2177 | /* +2 for \n and \0 */ |
2178 | buf = kmalloc(len + 2, GFP_KERNEL); | |
d8e83d26 SR |
2179 | if (!buf) { |
2180 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 2181 | return -ENOMEM; |
d8e83d26 | 2182 | } |
bc0c38d1 SR |
2183 | |
2184 | for (i = 0; trace_options[i]; i++) { | |
2185 | if (trace_flags & (1 << i)) | |
5c6a3ae1 | 2186 | r += sprintf(buf + r, "%s\n", trace_options[i]); |
bc0c38d1 | 2187 | else |
5c6a3ae1 | 2188 | r += sprintf(buf + r, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2189 | } |
2190 | ||
adf9f195 FW |
2191 | for (i = 0; trace_opts[i].name; i++) { |
2192 | if (tracer_flags & trace_opts[i].bit) | |
5c6a3ae1 | 2193 | r += sprintf(buf + r, "%s\n", |
adf9f195 FW |
2194 | trace_opts[i].name); |
2195 | else | |
5c6a3ae1 | 2196 | r += sprintf(buf + r, "no%s\n", |
adf9f195 FW |
2197 | trace_opts[i].name); |
2198 | } | |
d8e83d26 | 2199 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2200 | |
bc0c38d1 SR |
2201 | WARN_ON(r >= len + 2); |
2202 | ||
36dfe925 | 2203 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2204 | |
2205 | kfree(buf); | |
bc0c38d1 SR |
2206 | return r; |
2207 | } | |
2208 | ||
adf9f195 FW |
2209 | /* Try to assign a tracer specific option */ |
2210 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2211 | { | |
2212 | struct tracer_flags *trace_flags = trace->flags; | |
2213 | struct tracer_opt *opts = NULL; | |
2214 | int ret = 0, i = 0; | |
2215 | int len; | |
2216 | ||
2217 | for (i = 0; trace_flags->opts[i].name; i++) { | |
2218 | opts = &trace_flags->opts[i]; | |
2219 | len = strlen(opts->name); | |
2220 | ||
2221 | if (strncmp(cmp, opts->name, len) == 0) { | |
2222 | ret = trace->set_flag(trace_flags->val, | |
2223 | opts->bit, !neg); | |
2224 | break; | |
2225 | } | |
2226 | } | |
2227 | /* Not found */ | |
2228 | if (!trace_flags->opts[i].name) | |
2229 | return -EINVAL; | |
2230 | ||
2231 | /* Refused to handle */ | |
2232 | if (ret) | |
2233 | return ret; | |
2234 | ||
2235 | if (neg) | |
2236 | trace_flags->val &= ~opts->bit; | |
2237 | else | |
2238 | trace_flags->val |= opts->bit; | |
2239 | ||
2240 | return 0; | |
2241 | } | |
2242 | ||
af4617bd SR |
2243 | static void set_tracer_flags(unsigned int mask, int enabled) |
2244 | { | |
2245 | /* do nothing if flag is already set */ | |
2246 | if (!!(trace_flags & mask) == !!enabled) | |
2247 | return; | |
2248 | ||
2249 | if (enabled) | |
2250 | trace_flags |= mask; | |
2251 | else | |
2252 | trace_flags &= ~mask; | |
2253 | ||
2254 | if (mask == TRACE_ITER_GLOBAL_CLK) { | |
2255 | u64 (*func)(void); | |
2256 | ||
2257 | if (enabled) | |
2258 | func = trace_clock_global; | |
2259 | else | |
2260 | func = trace_clock_local; | |
2261 | ||
2262 | mutex_lock(&trace_types_lock); | |
2263 | ring_buffer_set_clock(global_trace.buffer, func); | |
2264 | ||
2265 | if (max_tr.buffer) | |
2266 | ring_buffer_set_clock(max_tr.buffer, func); | |
2267 | mutex_unlock(&trace_types_lock); | |
2268 | } | |
2269 | } | |
2270 | ||
bc0c38d1 | 2271 | static ssize_t |
ee6bce52 | 2272 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2273 | size_t cnt, loff_t *ppos) |
2274 | { | |
2275 | char buf[64]; | |
2276 | char *cmp = buf; | |
2277 | int neg = 0; | |
adf9f195 | 2278 | int ret; |
bc0c38d1 SR |
2279 | int i; |
2280 | ||
cffae437 SR |
2281 | if (cnt >= sizeof(buf)) |
2282 | return -EINVAL; | |
bc0c38d1 SR |
2283 | |
2284 | if (copy_from_user(&buf, ubuf, cnt)) | |
2285 | return -EFAULT; | |
2286 | ||
2287 | buf[cnt] = 0; | |
2288 | ||
2289 | if (strncmp(buf, "no", 2) == 0) { | |
2290 | neg = 1; | |
2291 | cmp += 2; | |
2292 | } | |
2293 | ||
2294 | for (i = 0; trace_options[i]; i++) { | |
2295 | int len = strlen(trace_options[i]); | |
2296 | ||
2297 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
af4617bd | 2298 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2299 | break; |
2300 | } | |
2301 | } | |
adf9f195 FW |
2302 | |
2303 | /* If no option could be set, test the specific tracer options */ | |
2304 | if (!trace_options[i]) { | |
d8e83d26 | 2305 | mutex_lock(&trace_types_lock); |
adf9f195 | 2306 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2307 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2308 | if (ret) |
2309 | return ret; | |
2310 | } | |
bc0c38d1 SR |
2311 | |
2312 | filp->f_pos += cnt; | |
2313 | ||
2314 | return cnt; | |
2315 | } | |
2316 | ||
5e2336a0 | 2317 | static const struct file_operations tracing_iter_fops = { |
c7078de1 | 2318 | .open = tracing_open_generic, |
ee6bce52 SR |
2319 | .read = tracing_trace_options_read, |
2320 | .write = tracing_trace_options_write, | |
bc0c38d1 SR |
2321 | }; |
2322 | ||
7bd2f24c IM |
2323 | static const char readme_msg[] = |
2324 | "tracing mini-HOWTO:\n\n" | |
2325 | "# mkdir /debug\n" | |
2326 | "# mount -t debugfs nodev /debug\n\n" | |
2327 | "# cat /debug/tracing/available_tracers\n" | |
2328 | "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n" | |
2329 | "# cat /debug/tracing/current_tracer\n" | |
2330 | "none\n" | |
2331 | "# echo sched_switch > /debug/tracing/current_tracer\n" | |
2332 | "# cat /debug/tracing/current_tracer\n" | |
2333 | "sched_switch\n" | |
ee6bce52 | 2334 | "# cat /debug/tracing/trace_options\n" |
7bd2f24c | 2335 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
ee6bce52 | 2336 | "# echo print-parent > /debug/tracing/trace_options\n" |
7bd2f24c IM |
2337 | "# echo 1 > /debug/tracing/tracing_enabled\n" |
2338 | "# cat /debug/tracing/trace > /tmp/trace.txt\n" | |
2339 | "echo 0 > /debug/tracing/tracing_enabled\n" | |
2340 | ; | |
2341 | ||
2342 | static ssize_t | |
2343 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2344 | size_t cnt, loff_t *ppos) | |
2345 | { | |
2346 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2347 | readme_msg, strlen(readme_msg)); | |
2348 | } | |
2349 | ||
5e2336a0 | 2350 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2351 | .open = tracing_open_generic, |
2352 | .read = tracing_readme_read, | |
7bd2f24c IM |
2353 | }; |
2354 | ||
bc0c38d1 SR |
2355 | static ssize_t |
2356 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2357 | size_t cnt, loff_t *ppos) | |
2358 | { | |
bc0c38d1 SR |
2359 | char buf[64]; |
2360 | int r; | |
2361 | ||
9036990d | 2362 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2363 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2364 | } |
2365 | ||
2366 | static ssize_t | |
2367 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2368 | size_t cnt, loff_t *ppos) | |
2369 | { | |
2370 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2371 | char buf[64]; |
5e39841c | 2372 | unsigned long val; |
c6caeeb1 | 2373 | int ret; |
bc0c38d1 | 2374 | |
cffae437 SR |
2375 | if (cnt >= sizeof(buf)) |
2376 | return -EINVAL; | |
bc0c38d1 SR |
2377 | |
2378 | if (copy_from_user(&buf, ubuf, cnt)) | |
2379 | return -EFAULT; | |
2380 | ||
2381 | buf[cnt] = 0; | |
2382 | ||
c6caeeb1 SR |
2383 | ret = strict_strtoul(buf, 10, &val); |
2384 | if (ret < 0) | |
2385 | return ret; | |
bc0c38d1 SR |
2386 | |
2387 | val = !!val; | |
2388 | ||
2389 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2390 | if (tracer_enabled ^ val) { |
2391 | if (val) { | |
bc0c38d1 | 2392 | tracer_enabled = 1; |
9036990d SR |
2393 | if (current_trace->start) |
2394 | current_trace->start(tr); | |
2395 | tracing_start(); | |
2396 | } else { | |
bc0c38d1 | 2397 | tracer_enabled = 0; |
9036990d SR |
2398 | tracing_stop(); |
2399 | if (current_trace->stop) | |
2400 | current_trace->stop(tr); | |
2401 | } | |
bc0c38d1 SR |
2402 | } |
2403 | mutex_unlock(&trace_types_lock); | |
2404 | ||
2405 | filp->f_pos += cnt; | |
2406 | ||
2407 | return cnt; | |
2408 | } | |
2409 | ||
2410 | static ssize_t | |
2411 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2412 | size_t cnt, loff_t *ppos) | |
2413 | { | |
2414 | char buf[max_tracer_type_len+2]; | |
2415 | int r; | |
2416 | ||
2417 | mutex_lock(&trace_types_lock); | |
2418 | if (current_trace) | |
2419 | r = sprintf(buf, "%s\n", current_trace->name); | |
2420 | else | |
2421 | r = sprintf(buf, "\n"); | |
2422 | mutex_unlock(&trace_types_lock); | |
2423 | ||
4bf39a94 | 2424 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2425 | } |
2426 | ||
b6f11df2 ACM |
2427 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2428 | { | |
2429 | tracing_reset_online_cpus(tr); | |
2430 | return t->init(tr); | |
2431 | } | |
2432 | ||
73c5162a SR |
2433 | static int tracing_resize_ring_buffer(unsigned long size) |
2434 | { | |
2435 | int ret; | |
2436 | ||
2437 | /* | |
2438 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2439 | * we use the size that was given, and we can forget about |
2440 | * expanding it later. | |
73c5162a SR |
2441 | */ |
2442 | ring_buffer_expanded = 1; | |
2443 | ||
2444 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2445 | if (ret < 0) | |
2446 | return ret; | |
2447 | ||
2448 | ret = ring_buffer_resize(max_tr.buffer, size); | |
2449 | if (ret < 0) { | |
2450 | int r; | |
2451 | ||
2452 | r = ring_buffer_resize(global_trace.buffer, | |
2453 | global_trace.entries); | |
2454 | if (r < 0) { | |
a123c52b SR |
2455 | /* |
2456 | * AARGH! We are left with different | |
2457 | * size max buffer!!!! | |
2458 | * The max buffer is our "snapshot" buffer. | |
2459 | * When a tracer needs a snapshot (one of the | |
2460 | * latency tracers), it swaps the max buffer | |
2461 | * with the saved snap shot. We succeeded to | |
2462 | * update the size of the main buffer, but failed to | |
2463 | * update the size of the max buffer. But when we tried | |
2464 | * to reset the main buffer to the original size, we | |
2465 | * failed there too. This is very unlikely to | |
2466 | * happen, but if it does, warn and kill all | |
2467 | * tracing. | |
2468 | */ | |
73c5162a SR |
2469 | WARN_ON(1); |
2470 | tracing_disabled = 1; | |
2471 | } | |
2472 | return ret; | |
2473 | } | |
2474 | ||
2475 | global_trace.entries = size; | |
2476 | ||
2477 | return ret; | |
2478 | } | |
2479 | ||
1852fcce SR |
2480 | /** |
2481 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2482 | * | |
2483 | * To save on memory when the tracing is never used on a system with it | |
2484 | * configured in. The ring buffers are set to a minimum size. But once | |
2485 | * a user starts to use the tracing facility, then they need to grow | |
2486 | * to their default size. | |
2487 | * | |
2488 | * This function is to be called when a tracer is about to be used. | |
2489 | */ | |
2490 | int tracing_update_buffers(void) | |
2491 | { | |
2492 | int ret = 0; | |
2493 | ||
1027fcb2 | 2494 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2495 | if (!ring_buffer_expanded) |
2496 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2497 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2498 | |
2499 | return ret; | |
2500 | } | |
2501 | ||
577b785f SR |
2502 | struct trace_option_dentry; |
2503 | ||
2504 | static struct trace_option_dentry * | |
2505 | create_trace_option_files(struct tracer *tracer); | |
2506 | ||
2507 | static void | |
2508 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2509 | ||
b2821ae6 | 2510 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2511 | { |
577b785f | 2512 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2513 | struct trace_array *tr = &global_trace; |
2514 | struct tracer *t; | |
d9e54076 | 2515 | int ret = 0; |
bc0c38d1 | 2516 | |
1027fcb2 SR |
2517 | mutex_lock(&trace_types_lock); |
2518 | ||
73c5162a SR |
2519 | if (!ring_buffer_expanded) { |
2520 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2521 | if (ret < 0) | |
59f586db | 2522 | goto out; |
73c5162a SR |
2523 | ret = 0; |
2524 | } | |
2525 | ||
bc0c38d1 SR |
2526 | for (t = trace_types; t; t = t->next) { |
2527 | if (strcmp(t->name, buf) == 0) | |
2528 | break; | |
2529 | } | |
c2931e05 FW |
2530 | if (!t) { |
2531 | ret = -EINVAL; | |
2532 | goto out; | |
2533 | } | |
2534 | if (t == current_trace) | |
bc0c38d1 SR |
2535 | goto out; |
2536 | ||
9f029e83 | 2537 | trace_branch_disable(); |
bc0c38d1 SR |
2538 | if (current_trace && current_trace->reset) |
2539 | current_trace->reset(tr); | |
2540 | ||
577b785f SR |
2541 | destroy_trace_option_files(topts); |
2542 | ||
bc0c38d1 | 2543 | current_trace = t; |
577b785f SR |
2544 | |
2545 | topts = create_trace_option_files(current_trace); | |
2546 | ||
1c80025a | 2547 | if (t->init) { |
b6f11df2 | 2548 | ret = tracer_init(t, tr); |
1c80025a FW |
2549 | if (ret) |
2550 | goto out; | |
2551 | } | |
bc0c38d1 | 2552 | |
9f029e83 | 2553 | trace_branch_enable(tr); |
bc0c38d1 SR |
2554 | out: |
2555 | mutex_unlock(&trace_types_lock); | |
2556 | ||
d9e54076 PZ |
2557 | return ret; |
2558 | } | |
2559 | ||
2560 | static ssize_t | |
2561 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2562 | size_t cnt, loff_t *ppos) | |
2563 | { | |
2564 | char buf[max_tracer_type_len+1]; | |
2565 | int i; | |
2566 | size_t ret; | |
e6e7a65a FW |
2567 | int err; |
2568 | ||
2569 | ret = cnt; | |
d9e54076 PZ |
2570 | |
2571 | if (cnt > max_tracer_type_len) | |
2572 | cnt = max_tracer_type_len; | |
2573 | ||
2574 | if (copy_from_user(&buf, ubuf, cnt)) | |
2575 | return -EFAULT; | |
2576 | ||
2577 | buf[cnt] = 0; | |
2578 | ||
2579 | /* strip ending whitespace. */ | |
2580 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2581 | buf[i] = 0; | |
2582 | ||
e6e7a65a FW |
2583 | err = tracing_set_tracer(buf); |
2584 | if (err) | |
2585 | return err; | |
d9e54076 | 2586 | |
e6e7a65a | 2587 | filp->f_pos += ret; |
bc0c38d1 | 2588 | |
c2931e05 | 2589 | return ret; |
bc0c38d1 SR |
2590 | } |
2591 | ||
2592 | static ssize_t | |
2593 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2594 | size_t cnt, loff_t *ppos) | |
2595 | { | |
2596 | unsigned long *ptr = filp->private_data; | |
2597 | char buf[64]; | |
2598 | int r; | |
2599 | ||
cffae437 | 2600 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2601 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2602 | if (r > sizeof(buf)) |
2603 | r = sizeof(buf); | |
4bf39a94 | 2604 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2605 | } |
2606 | ||
2607 | static ssize_t | |
2608 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2609 | size_t cnt, loff_t *ppos) | |
2610 | { | |
5e39841c | 2611 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2612 | char buf[64]; |
5e39841c | 2613 | unsigned long val; |
c6caeeb1 | 2614 | int ret; |
bc0c38d1 | 2615 | |
cffae437 SR |
2616 | if (cnt >= sizeof(buf)) |
2617 | return -EINVAL; | |
bc0c38d1 SR |
2618 | |
2619 | if (copy_from_user(&buf, ubuf, cnt)) | |
2620 | return -EFAULT; | |
2621 | ||
2622 | buf[cnt] = 0; | |
2623 | ||
c6caeeb1 SR |
2624 | ret = strict_strtoul(buf, 10, &val); |
2625 | if (ret < 0) | |
2626 | return ret; | |
bc0c38d1 SR |
2627 | |
2628 | *ptr = val * 1000; | |
2629 | ||
2630 | return cnt; | |
2631 | } | |
2632 | ||
b3806b43 SR |
2633 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2634 | { | |
b04cc6b1 | 2635 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2636 | struct trace_iterator *iter; |
b04cc6b1 | 2637 | int ret = 0; |
b3806b43 SR |
2638 | |
2639 | if (tracing_disabled) | |
2640 | return -ENODEV; | |
2641 | ||
b04cc6b1 FW |
2642 | mutex_lock(&trace_types_lock); |
2643 | ||
2644 | /* We only allow one reader per cpu */ | |
2645 | if (cpu_file == TRACE_PIPE_ALL_CPU) { | |
2646 | if (!cpumask_empty(tracing_reader_cpumask)) { | |
2647 | ret = -EBUSY; | |
2648 | goto out; | |
2649 | } | |
2650 | cpumask_setall(tracing_reader_cpumask); | |
2651 | } else { | |
2652 | if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask)) | |
2653 | cpumask_set_cpu(cpu_file, tracing_reader_cpumask); | |
2654 | else { | |
2655 | ret = -EBUSY; | |
2656 | goto out; | |
2657 | } | |
b3806b43 SR |
2658 | } |
2659 | ||
2660 | /* create a buffer to store the information to pass to userspace */ | |
2661 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2662 | if (!iter) { |
2663 | ret = -ENOMEM; | |
2664 | goto out; | |
2665 | } | |
b3806b43 | 2666 | |
d7350c3f FW |
2667 | /* |
2668 | * We make a copy of the current tracer to avoid concurrent | |
2669 | * changes on it while we are reading. | |
2670 | */ | |
2671 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
2672 | if (!iter->trace) { | |
2673 | ret = -ENOMEM; | |
2674 | goto fail; | |
2675 | } | |
2676 | if (current_trace) | |
2677 | *iter->trace = *current_trace; | |
2678 | ||
4462344e | 2679 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 2680 | ret = -ENOMEM; |
d7350c3f | 2681 | goto fail; |
4462344e RR |
2682 | } |
2683 | ||
a309720c | 2684 | /* trace pipe does not show start of buffer */ |
4462344e | 2685 | cpumask_setall(iter->started); |
a309720c | 2686 | |
b04cc6b1 | 2687 | iter->cpu_file = cpu_file; |
b3806b43 | 2688 | iter->tr = &global_trace; |
d7350c3f | 2689 | mutex_init(&iter->mutex); |
b3806b43 SR |
2690 | filp->private_data = iter; |
2691 | ||
107bad8b SR |
2692 | if (iter->trace->pipe_open) |
2693 | iter->trace->pipe_open(iter); | |
107bad8b | 2694 | |
b04cc6b1 FW |
2695 | out: |
2696 | mutex_unlock(&trace_types_lock); | |
2697 | return ret; | |
d7350c3f FW |
2698 | |
2699 | fail: | |
2700 | kfree(iter->trace); | |
2701 | kfree(iter); | |
2702 | mutex_unlock(&trace_types_lock); | |
2703 | return ret; | |
b3806b43 SR |
2704 | } |
2705 | ||
2706 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2707 | { | |
2708 | struct trace_iterator *iter = file->private_data; | |
2709 | ||
b04cc6b1 FW |
2710 | mutex_lock(&trace_types_lock); |
2711 | ||
2712 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) | |
2713 | cpumask_clear(tracing_reader_cpumask); | |
2714 | else | |
2715 | cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); | |
2716 | ||
2717 | mutex_unlock(&trace_types_lock); | |
2718 | ||
4462344e | 2719 | free_cpumask_var(iter->started); |
d7350c3f FW |
2720 | mutex_destroy(&iter->mutex); |
2721 | kfree(iter->trace); | |
b3806b43 | 2722 | kfree(iter); |
b3806b43 SR |
2723 | |
2724 | return 0; | |
2725 | } | |
2726 | ||
2a2cc8f7 SSP |
2727 | static unsigned int |
2728 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2729 | { | |
2730 | struct trace_iterator *iter = filp->private_data; | |
2731 | ||
2732 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2733 | /* | |
2734 | * Always select as readable when in blocking mode | |
2735 | */ | |
2736 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2737 | } else { |
2a2cc8f7 SSP |
2738 | if (!trace_empty(iter)) |
2739 | return POLLIN | POLLRDNORM; | |
2740 | poll_wait(filp, &trace_wait, poll_table); | |
2741 | if (!trace_empty(iter)) | |
2742 | return POLLIN | POLLRDNORM; | |
2743 | ||
2744 | return 0; | |
2745 | } | |
2746 | } | |
2747 | ||
6eaaa5d5 FW |
2748 | |
2749 | void default_wait_pipe(struct trace_iterator *iter) | |
2750 | { | |
2751 | DEFINE_WAIT(wait); | |
2752 | ||
2753 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
2754 | ||
2755 | if (trace_empty(iter)) | |
2756 | schedule(); | |
2757 | ||
2758 | finish_wait(&trace_wait, &wait); | |
2759 | } | |
2760 | ||
2761 | /* | |
2762 | * This is a make-shift waitqueue. | |
2763 | * A tracer might use this callback on some rare cases: | |
2764 | * | |
2765 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
2766 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
2767 | * 2) the function tracers, trace all functions, we don't want | |
2768 | * the overhead of calling wake_up and friends | |
2769 | * (and tracing them too) | |
2770 | * | |
2771 | * Anyway, this is really very primitive wakeup. | |
2772 | */ | |
2773 | void poll_wait_pipe(struct trace_iterator *iter) | |
2774 | { | |
2775 | set_current_state(TASK_INTERRUPTIBLE); | |
2776 | /* sleep for 100 msecs, and try again. */ | |
2777 | schedule_timeout(HZ / 10); | |
2778 | } | |
2779 | ||
ff98781b EGM |
2780 | /* Must be called with trace_types_lock mutex held. */ |
2781 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
2782 | { |
2783 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 2784 | |
b3806b43 | 2785 | while (trace_empty(iter)) { |
2dc8f095 | 2786 | |
107bad8b | 2787 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 2788 | return -EAGAIN; |
107bad8b | 2789 | } |
2dc8f095 | 2790 | |
d7350c3f | 2791 | mutex_unlock(&iter->mutex); |
107bad8b | 2792 | |
6eaaa5d5 | 2793 | iter->trace->wait_pipe(iter); |
b3806b43 | 2794 | |
d7350c3f | 2795 | mutex_lock(&iter->mutex); |
107bad8b | 2796 | |
6eaaa5d5 | 2797 | if (signal_pending(current)) |
ff98781b | 2798 | return -EINTR; |
b3806b43 SR |
2799 | |
2800 | /* | |
2801 | * We block until we read something and tracing is disabled. | |
2802 | * We still block if tracing is disabled, but we have never | |
2803 | * read anything. This allows a user to cat this file, and | |
2804 | * then enable tracing. But after we have read something, | |
2805 | * we give an EOF when tracing is again disabled. | |
2806 | * | |
2807 | * iter->pos will be 0 if we haven't read anything. | |
2808 | */ | |
2809 | if (!tracer_enabled && iter->pos) | |
2810 | break; | |
b3806b43 SR |
2811 | } |
2812 | ||
ff98781b EGM |
2813 | return 1; |
2814 | } | |
2815 | ||
2816 | /* | |
2817 | * Consumer reader. | |
2818 | */ | |
2819 | static ssize_t | |
2820 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2821 | size_t cnt, loff_t *ppos) | |
2822 | { | |
2823 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 2824 | static struct tracer *old_tracer; |
ff98781b EGM |
2825 | ssize_t sret; |
2826 | ||
2827 | /* return any leftover data */ | |
2828 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
2829 | if (sret != -EBUSY) | |
2830 | return sret; | |
2831 | ||
f9520750 | 2832 | trace_seq_init(&iter->seq); |
ff98781b | 2833 | |
d7350c3f | 2834 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 2835 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2836 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2837 | old_tracer = current_trace; | |
2838 | *iter->trace = *current_trace; | |
2839 | } | |
2840 | mutex_unlock(&trace_types_lock); | |
2841 | ||
2842 | /* | |
2843 | * Avoid more than one consumer on a single file descriptor | |
2844 | * This is just a matter of traces coherency, the ring buffer itself | |
2845 | * is protected. | |
2846 | */ | |
2847 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
2848 | if (iter->trace->read) { |
2849 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
2850 | if (sret) | |
2851 | goto out; | |
2852 | } | |
2853 | ||
2854 | waitagain: | |
2855 | sret = tracing_wait_pipe(filp); | |
2856 | if (sret <= 0) | |
2857 | goto out; | |
2858 | ||
b3806b43 | 2859 | /* stop when tracing is finished */ |
ff98781b EGM |
2860 | if (trace_empty(iter)) { |
2861 | sret = 0; | |
107bad8b | 2862 | goto out; |
ff98781b | 2863 | } |
b3806b43 SR |
2864 | |
2865 | if (cnt >= PAGE_SIZE) | |
2866 | cnt = PAGE_SIZE - 1; | |
2867 | ||
53d0aa77 | 2868 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
2869 | memset(&iter->seq, 0, |
2870 | sizeof(struct trace_iterator) - | |
2871 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 2872 | iter->pos = -1; |
b3806b43 | 2873 | |
088b1e42 | 2874 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 2875 | enum print_line_t ret; |
088b1e42 SR |
2876 | int len = iter->seq.len; |
2877 | ||
f9896bf3 | 2878 | ret = print_trace_line(iter); |
2c4f035f | 2879 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
2880 | /* don't print partial lines */ |
2881 | iter->seq.len = len; | |
b3806b43 | 2882 | break; |
088b1e42 | 2883 | } |
b91facc3 FW |
2884 | if (ret != TRACE_TYPE_NO_CONSUME) |
2885 | trace_consume(iter); | |
b3806b43 SR |
2886 | |
2887 | if (iter->seq.len >= cnt) | |
2888 | break; | |
b3806b43 SR |
2889 | } |
2890 | ||
b3806b43 | 2891 | /* Now copy what we have to the user */ |
6c6c2796 PP |
2892 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2893 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 2894 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
2895 | |
2896 | /* | |
2897 | * If there was nothing to send to user, inspite of consuming trace | |
2898 | * entries, go back to wait for more entries. | |
2899 | */ | |
6c6c2796 | 2900 | if (sret == -EBUSY) |
9ff4b974 | 2901 | goto waitagain; |
b3806b43 | 2902 | |
107bad8b | 2903 | out: |
d7350c3f | 2904 | mutex_unlock(&iter->mutex); |
107bad8b | 2905 | |
6c6c2796 | 2906 | return sret; |
b3806b43 SR |
2907 | } |
2908 | ||
3c56819b EGM |
2909 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
2910 | struct pipe_buffer *buf) | |
2911 | { | |
2912 | __free_page(buf->page); | |
2913 | } | |
2914 | ||
2915 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
2916 | unsigned int idx) | |
2917 | { | |
2918 | __free_page(spd->pages[idx]); | |
2919 | } | |
2920 | ||
2921 | static struct pipe_buf_operations tracing_pipe_buf_ops = { | |
34cd4998 SR |
2922 | .can_merge = 0, |
2923 | .map = generic_pipe_buf_map, | |
2924 | .unmap = generic_pipe_buf_unmap, | |
2925 | .confirm = generic_pipe_buf_confirm, | |
2926 | .release = tracing_pipe_buf_release, | |
2927 | .steal = generic_pipe_buf_steal, | |
2928 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
2929 | }; |
2930 | ||
34cd4998 | 2931 | static size_t |
fa7c7f6e | 2932 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
2933 | { |
2934 | size_t count; | |
2935 | int ret; | |
2936 | ||
2937 | /* Seq buffer is page-sized, exactly what we need. */ | |
2938 | for (;;) { | |
2939 | count = iter->seq.len; | |
2940 | ret = print_trace_line(iter); | |
2941 | count = iter->seq.len - count; | |
2942 | if (rem < count) { | |
2943 | rem = 0; | |
2944 | iter->seq.len -= count; | |
2945 | break; | |
2946 | } | |
2947 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
2948 | iter->seq.len -= count; | |
2949 | break; | |
2950 | } | |
2951 | ||
2952 | trace_consume(iter); | |
2953 | rem -= count; | |
2954 | if (!find_next_entry_inc(iter)) { | |
2955 | rem = 0; | |
2956 | iter->ent = NULL; | |
2957 | break; | |
2958 | } | |
2959 | } | |
2960 | ||
2961 | return rem; | |
2962 | } | |
2963 | ||
3c56819b EGM |
2964 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
2965 | loff_t *ppos, | |
2966 | struct pipe_inode_info *pipe, | |
2967 | size_t len, | |
2968 | unsigned int flags) | |
2969 | { | |
2970 | struct page *pages[PIPE_BUFFERS]; | |
2971 | struct partial_page partial[PIPE_BUFFERS]; | |
2972 | struct trace_iterator *iter = filp->private_data; | |
2973 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
2974 | .pages = pages, |
2975 | .partial = partial, | |
2976 | .nr_pages = 0, /* This gets updated below. */ | |
2977 | .flags = flags, | |
2978 | .ops = &tracing_pipe_buf_ops, | |
2979 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 2980 | }; |
d7350c3f | 2981 | static struct tracer *old_tracer; |
3c56819b | 2982 | ssize_t ret; |
34cd4998 | 2983 | size_t rem; |
3c56819b EGM |
2984 | unsigned int i; |
2985 | ||
d7350c3f | 2986 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 2987 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2988 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2989 | old_tracer = current_trace; | |
2990 | *iter->trace = *current_trace; | |
2991 | } | |
2992 | mutex_unlock(&trace_types_lock); | |
2993 | ||
2994 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
2995 | |
2996 | if (iter->trace->splice_read) { | |
2997 | ret = iter->trace->splice_read(iter, filp, | |
2998 | ppos, pipe, len, flags); | |
2999 | if (ret) | |
34cd4998 | 3000 | goto out_err; |
3c56819b EGM |
3001 | } |
3002 | ||
3003 | ret = tracing_wait_pipe(filp); | |
3004 | if (ret <= 0) | |
34cd4998 | 3005 | goto out_err; |
3c56819b EGM |
3006 | |
3007 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
3008 | ret = -EFAULT; | |
34cd4998 | 3009 | goto out_err; |
3c56819b EGM |
3010 | } |
3011 | ||
3012 | /* Fill as many pages as possible. */ | |
3013 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
3014 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
3015 | if (!pages[i]) |
3016 | break; | |
3c56819b | 3017 | |
fa7c7f6e | 3018 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3019 | |
3020 | /* Copy the data into the page, so we can start over. */ | |
3021 | ret = trace_seq_to_buffer(&iter->seq, | |
3022 | page_address(pages[i]), | |
3023 | iter->seq.len); | |
3024 | if (ret < 0) { | |
3025 | __free_page(pages[i]); | |
3026 | break; | |
3027 | } | |
3028 | partial[i].offset = 0; | |
3029 | partial[i].len = iter->seq.len; | |
3030 | ||
f9520750 | 3031 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3032 | } |
3033 | ||
d7350c3f | 3034 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3035 | |
3036 | spd.nr_pages = i; | |
3037 | ||
3038 | return splice_to_pipe(pipe, &spd); | |
3039 | ||
34cd4998 | 3040 | out_err: |
d7350c3f | 3041 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3042 | |
3043 | return ret; | |
3044 | } | |
3045 | ||
a98a3c3f SR |
3046 | static ssize_t |
3047 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3048 | size_t cnt, loff_t *ppos) | |
3049 | { | |
3050 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3051 | char buf[96]; |
a98a3c3f SR |
3052 | int r; |
3053 | ||
db526ca3 SR |
3054 | mutex_lock(&trace_types_lock); |
3055 | if (!ring_buffer_expanded) | |
3056 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3057 | tr->entries >> 10, | |
3058 | trace_buf_size >> 10); | |
3059 | else | |
3060 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3061 | mutex_unlock(&trace_types_lock); | |
3062 | ||
a98a3c3f SR |
3063 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3064 | } | |
3065 | ||
3066 | static ssize_t | |
3067 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3068 | size_t cnt, loff_t *ppos) | |
3069 | { | |
3070 | unsigned long val; | |
3071 | char buf[64]; | |
bf5e6519 | 3072 | int ret, cpu; |
a98a3c3f | 3073 | |
cffae437 SR |
3074 | if (cnt >= sizeof(buf)) |
3075 | return -EINVAL; | |
a98a3c3f SR |
3076 | |
3077 | if (copy_from_user(&buf, ubuf, cnt)) | |
3078 | return -EFAULT; | |
3079 | ||
3080 | buf[cnt] = 0; | |
3081 | ||
c6caeeb1 SR |
3082 | ret = strict_strtoul(buf, 10, &val); |
3083 | if (ret < 0) | |
3084 | return ret; | |
a98a3c3f SR |
3085 | |
3086 | /* must have at least 1 entry */ | |
3087 | if (!val) | |
3088 | return -EINVAL; | |
3089 | ||
3090 | mutex_lock(&trace_types_lock); | |
3091 | ||
c76f0694 | 3092 | tracing_stop(); |
a98a3c3f | 3093 | |
bf5e6519 SR |
3094 | /* disable all cpu buffers */ |
3095 | for_each_tracing_cpu(cpu) { | |
3096 | if (global_trace.data[cpu]) | |
3097 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3098 | if (max_tr.data[cpu]) | |
3099 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3100 | } | |
3101 | ||
1696b2b0 SR |
3102 | /* value is in KB */ |
3103 | val <<= 10; | |
3104 | ||
3928a8a2 | 3105 | if (val != global_trace.entries) { |
73c5162a | 3106 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3107 | if (ret < 0) { |
3108 | cnt = ret; | |
3eefae99 SR |
3109 | goto out; |
3110 | } | |
a98a3c3f SR |
3111 | } |
3112 | ||
3113 | filp->f_pos += cnt; | |
3114 | ||
19384c03 SR |
3115 | /* If check pages failed, return ENOMEM */ |
3116 | if (tracing_disabled) | |
3117 | cnt = -ENOMEM; | |
a98a3c3f | 3118 | out: |
bf5e6519 SR |
3119 | for_each_tracing_cpu(cpu) { |
3120 | if (global_trace.data[cpu]) | |
3121 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3122 | if (max_tr.data[cpu]) | |
3123 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3124 | } | |
3125 | ||
c76f0694 | 3126 | tracing_start(); |
a98a3c3f SR |
3127 | max_tr.entries = global_trace.entries; |
3128 | mutex_unlock(&trace_types_lock); | |
3129 | ||
3130 | return cnt; | |
3131 | } | |
3132 | ||
5bf9a1ee PP |
3133 | static int mark_printk(const char *fmt, ...) |
3134 | { | |
3135 | int ret; | |
3136 | va_list args; | |
3137 | va_start(args, fmt); | |
40ce74f1 | 3138 | ret = trace_vprintk(0, fmt, args); |
5bf9a1ee PP |
3139 | va_end(args); |
3140 | return ret; | |
3141 | } | |
3142 | ||
3143 | static ssize_t | |
3144 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3145 | size_t cnt, loff_t *fpos) | |
3146 | { | |
3147 | char *buf; | |
3148 | char *end; | |
5bf9a1ee | 3149 | |
c76f0694 | 3150 | if (tracing_disabled) |
5bf9a1ee PP |
3151 | return -EINVAL; |
3152 | ||
3153 | if (cnt > TRACE_BUF_SIZE) | |
3154 | cnt = TRACE_BUF_SIZE; | |
3155 | ||
3156 | buf = kmalloc(cnt + 1, GFP_KERNEL); | |
3157 | if (buf == NULL) | |
3158 | return -ENOMEM; | |
3159 | ||
3160 | if (copy_from_user(buf, ubuf, cnt)) { | |
3161 | kfree(buf); | |
3162 | return -EFAULT; | |
3163 | } | |
3164 | ||
3165 | /* Cut from the first nil or newline. */ | |
3166 | buf[cnt] = '\0'; | |
3167 | end = strchr(buf, '\n'); | |
3168 | if (end) | |
3169 | *end = '\0'; | |
3170 | ||
3171 | cnt = mark_printk("%s\n", buf); | |
3172 | kfree(buf); | |
3173 | *fpos += cnt; | |
3174 | ||
3175 | return cnt; | |
3176 | } | |
3177 | ||
5e2336a0 | 3178 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3179 | .open = tracing_open_generic, |
3180 | .read = tracing_max_lat_read, | |
3181 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
3182 | }; |
3183 | ||
5e2336a0 | 3184 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3185 | .open = tracing_open_generic, |
3186 | .read = tracing_ctrl_read, | |
3187 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
3188 | }; |
3189 | ||
5e2336a0 | 3190 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3191 | .open = tracing_open_generic, |
3192 | .read = tracing_set_trace_read, | |
3193 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
3194 | }; |
3195 | ||
5e2336a0 | 3196 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3197 | .open = tracing_open_pipe, |
2a2cc8f7 | 3198 | .poll = tracing_poll_pipe, |
4bf39a94 | 3199 | .read = tracing_read_pipe, |
3c56819b | 3200 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3201 | .release = tracing_release_pipe, |
b3806b43 SR |
3202 | }; |
3203 | ||
5e2336a0 | 3204 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3205 | .open = tracing_open_generic, |
3206 | .read = tracing_entries_read, | |
3207 | .write = tracing_entries_write, | |
3208 | }; | |
3209 | ||
5e2336a0 | 3210 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3211 | .open = tracing_open_generic, |
5bf9a1ee PP |
3212 | .write = tracing_mark_write, |
3213 | }; | |
3214 | ||
2cadf913 SR |
3215 | struct ftrace_buffer_info { |
3216 | struct trace_array *tr; | |
3217 | void *spare; | |
3218 | int cpu; | |
3219 | unsigned int read; | |
3220 | }; | |
3221 | ||
3222 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3223 | { | |
3224 | int cpu = (int)(long)inode->i_private; | |
3225 | struct ftrace_buffer_info *info; | |
3226 | ||
3227 | if (tracing_disabled) | |
3228 | return -ENODEV; | |
3229 | ||
3230 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3231 | if (!info) | |
3232 | return -ENOMEM; | |
3233 | ||
3234 | info->tr = &global_trace; | |
3235 | info->cpu = cpu; | |
3236 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3237 | /* Force reading ring buffer for first read */ | |
3238 | info->read = (unsigned int)-1; | |
3239 | if (!info->spare) | |
3240 | goto out; | |
3241 | ||
3242 | filp->private_data = info; | |
3243 | ||
3244 | return 0; | |
3245 | ||
3246 | out: | |
3247 | kfree(info); | |
3248 | return -ENOMEM; | |
3249 | } | |
3250 | ||
3251 | static ssize_t | |
3252 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3253 | size_t count, loff_t *ppos) | |
3254 | { | |
3255 | struct ftrace_buffer_info *info = filp->private_data; | |
3256 | unsigned int pos; | |
3257 | ssize_t ret; | |
3258 | size_t size; | |
3259 | ||
2dc5d12b SR |
3260 | if (!count) |
3261 | return 0; | |
3262 | ||
2cadf913 SR |
3263 | /* Do we have previous read data to read? */ |
3264 | if (info->read < PAGE_SIZE) | |
3265 | goto read; | |
3266 | ||
3267 | info->read = 0; | |
3268 | ||
3269 | ret = ring_buffer_read_page(info->tr->buffer, | |
3270 | &info->spare, | |
3271 | count, | |
3272 | info->cpu, 0); | |
3273 | if (ret < 0) | |
3274 | return 0; | |
3275 | ||
3276 | pos = ring_buffer_page_len(info->spare); | |
3277 | ||
3278 | if (pos < PAGE_SIZE) | |
3279 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3280 | ||
3281 | read: | |
3282 | size = PAGE_SIZE - info->read; | |
3283 | if (size > count) | |
3284 | size = count; | |
3285 | ||
3286 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3287 | if (ret == size) |
2cadf913 | 3288 | return -EFAULT; |
2dc5d12b SR |
3289 | size -= ret; |
3290 | ||
2cadf913 SR |
3291 | *ppos += size; |
3292 | info->read += size; | |
3293 | ||
3294 | return size; | |
3295 | } | |
3296 | ||
3297 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3298 | { | |
3299 | struct ftrace_buffer_info *info = file->private_data; | |
3300 | ||
3301 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
3302 | kfree(info); | |
3303 | ||
3304 | return 0; | |
3305 | } | |
3306 | ||
3307 | struct buffer_ref { | |
3308 | struct ring_buffer *buffer; | |
3309 | void *page; | |
3310 | int ref; | |
3311 | }; | |
3312 | ||
3313 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3314 | struct pipe_buffer *buf) | |
3315 | { | |
3316 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3317 | ||
3318 | if (--ref->ref) | |
3319 | return; | |
3320 | ||
3321 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3322 | kfree(ref); | |
3323 | buf->private = 0; | |
3324 | } | |
3325 | ||
3326 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3327 | struct pipe_buffer *buf) | |
3328 | { | |
3329 | return 1; | |
3330 | } | |
3331 | ||
3332 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3333 | struct pipe_buffer *buf) | |
3334 | { | |
3335 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3336 | ||
3337 | ref->ref++; | |
3338 | } | |
3339 | ||
3340 | /* Pipe buffer operations for a buffer. */ | |
3341 | static struct pipe_buf_operations buffer_pipe_buf_ops = { | |
3342 | .can_merge = 0, | |
3343 | .map = generic_pipe_buf_map, | |
3344 | .unmap = generic_pipe_buf_unmap, | |
3345 | .confirm = generic_pipe_buf_confirm, | |
3346 | .release = buffer_pipe_buf_release, | |
3347 | .steal = buffer_pipe_buf_steal, | |
3348 | .get = buffer_pipe_buf_get, | |
3349 | }; | |
3350 | ||
3351 | /* | |
3352 | * Callback from splice_to_pipe(), if we need to release some pages | |
3353 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3354 | */ | |
3355 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3356 | { | |
3357 | struct buffer_ref *ref = | |
3358 | (struct buffer_ref *)spd->partial[i].private; | |
3359 | ||
3360 | if (--ref->ref) | |
3361 | return; | |
3362 | ||
3363 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3364 | kfree(ref); | |
3365 | spd->partial[i].private = 0; | |
3366 | } | |
3367 | ||
3368 | static ssize_t | |
3369 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3370 | struct pipe_inode_info *pipe, size_t len, | |
3371 | unsigned int flags) | |
3372 | { | |
3373 | struct ftrace_buffer_info *info = file->private_data; | |
3374 | struct partial_page partial[PIPE_BUFFERS]; | |
3375 | struct page *pages[PIPE_BUFFERS]; | |
3376 | struct splice_pipe_desc spd = { | |
3377 | .pages = pages, | |
3378 | .partial = partial, | |
3379 | .flags = flags, | |
3380 | .ops = &buffer_pipe_buf_ops, | |
3381 | .spd_release = buffer_spd_release, | |
3382 | }; | |
3383 | struct buffer_ref *ref; | |
3384 | int size, i; | |
3385 | size_t ret; | |
3386 | ||
3387 | /* | |
3388 | * We can't seek on a buffer input | |
3389 | */ | |
3390 | if (unlikely(*ppos)) | |
3391 | return -ESPIPE; | |
3392 | ||
3393 | ||
3394 | for (i = 0; i < PIPE_BUFFERS && len; i++, len -= size) { | |
3395 | struct page *page; | |
3396 | int r; | |
3397 | ||
3398 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3399 | if (!ref) | |
3400 | break; | |
3401 | ||
3402 | ref->buffer = info->tr->buffer; | |
3403 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3404 | if (!ref->page) { | |
3405 | kfree(ref); | |
3406 | break; | |
3407 | } | |
3408 | ||
3409 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
3410 | len, info->cpu, 0); | |
3411 | if (r < 0) { | |
3412 | ring_buffer_free_read_page(ref->buffer, | |
3413 | ref->page); | |
3414 | kfree(ref); | |
3415 | break; | |
3416 | } | |
3417 | ||
3418 | /* | |
3419 | * zero out any left over data, this is going to | |
3420 | * user land. | |
3421 | */ | |
3422 | size = ring_buffer_page_len(ref->page); | |
3423 | if (size < PAGE_SIZE) | |
3424 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3425 | ||
3426 | page = virt_to_page(ref->page); | |
3427 | ||
3428 | spd.pages[i] = page; | |
3429 | spd.partial[i].len = PAGE_SIZE; | |
3430 | spd.partial[i].offset = 0; | |
3431 | spd.partial[i].private = (unsigned long)ref; | |
3432 | spd.nr_pages++; | |
3433 | } | |
3434 | ||
3435 | spd.nr_pages = i; | |
3436 | ||
3437 | /* did we read anything? */ | |
3438 | if (!spd.nr_pages) { | |
3439 | if (flags & SPLICE_F_NONBLOCK) | |
3440 | ret = -EAGAIN; | |
3441 | else | |
3442 | ret = 0; | |
3443 | /* TODO: block */ | |
3444 | return ret; | |
3445 | } | |
3446 | ||
3447 | ret = splice_to_pipe(pipe, &spd); | |
3448 | ||
3449 | return ret; | |
3450 | } | |
3451 | ||
3452 | static const struct file_operations tracing_buffers_fops = { | |
3453 | .open = tracing_buffers_open, | |
3454 | .read = tracing_buffers_read, | |
3455 | .release = tracing_buffers_release, | |
3456 | .splice_read = tracing_buffers_splice_read, | |
3457 | .llseek = no_llseek, | |
3458 | }; | |
3459 | ||
bc0c38d1 SR |
3460 | #ifdef CONFIG_DYNAMIC_FTRACE |
3461 | ||
b807c3d0 SR |
3462 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3463 | { | |
3464 | return 0; | |
3465 | } | |
3466 | ||
bc0c38d1 | 3467 | static ssize_t |
b807c3d0 | 3468 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3469 | size_t cnt, loff_t *ppos) |
3470 | { | |
a26a2a27 SR |
3471 | static char ftrace_dyn_info_buffer[1024]; |
3472 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3473 | unsigned long *p = filp->private_data; |
b807c3d0 | 3474 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3475 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3476 | int r; |
3477 | ||
b807c3d0 SR |
3478 | mutex_lock(&dyn_info_mutex); |
3479 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3480 | |
a26a2a27 | 3481 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3482 | buf[r++] = '\n'; |
3483 | ||
3484 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3485 | ||
3486 | mutex_unlock(&dyn_info_mutex); | |
3487 | ||
3488 | return r; | |
bc0c38d1 SR |
3489 | } |
3490 | ||
5e2336a0 | 3491 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3492 | .open = tracing_open_generic, |
b807c3d0 | 3493 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3494 | }; |
3495 | #endif | |
3496 | ||
3497 | static struct dentry *d_tracer; | |
3498 | ||
3499 | struct dentry *tracing_init_dentry(void) | |
3500 | { | |
3501 | static int once; | |
3502 | ||
3503 | if (d_tracer) | |
3504 | return d_tracer; | |
3505 | ||
3e1f60b8 FW |
3506 | if (!debugfs_initialized()) |
3507 | return NULL; | |
3508 | ||
bc0c38d1 SR |
3509 | d_tracer = debugfs_create_dir("tracing", NULL); |
3510 | ||
3511 | if (!d_tracer && !once) { | |
3512 | once = 1; | |
3513 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3514 | return NULL; | |
3515 | } | |
3516 | ||
3517 | return d_tracer; | |
3518 | } | |
3519 | ||
b04cc6b1 FW |
3520 | static struct dentry *d_percpu; |
3521 | ||
3522 | struct dentry *tracing_dentry_percpu(void) | |
3523 | { | |
3524 | static int once; | |
3525 | struct dentry *d_tracer; | |
3526 | ||
3527 | if (d_percpu) | |
3528 | return d_percpu; | |
3529 | ||
3530 | d_tracer = tracing_init_dentry(); | |
3531 | ||
3532 | if (!d_tracer) | |
3533 | return NULL; | |
3534 | ||
3535 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
3536 | ||
3537 | if (!d_percpu && !once) { | |
3538 | once = 1; | |
3539 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
3540 | return NULL; | |
3541 | } | |
3542 | ||
3543 | return d_percpu; | |
3544 | } | |
3545 | ||
3546 | static void tracing_init_debugfs_percpu(long cpu) | |
3547 | { | |
3548 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
8656e7a2 FW |
3549 | struct dentry *entry, *d_cpu; |
3550 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ | |
3551 | char cpu_dir[7]; | |
b04cc6b1 FW |
3552 | |
3553 | if (cpu > 999 || cpu < 0) | |
3554 | return; | |
3555 | ||
8656e7a2 FW |
3556 | sprintf(cpu_dir, "cpu%ld", cpu); |
3557 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
3558 | if (!d_cpu) { | |
3559 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
3560 | return; | |
3561 | } | |
b04cc6b1 | 3562 | |
8656e7a2 FW |
3563 | /* per cpu trace_pipe */ |
3564 | entry = debugfs_create_file("trace_pipe", 0444, d_cpu, | |
b04cc6b1 FW |
3565 | (void *) cpu, &tracing_pipe_fops); |
3566 | if (!entry) | |
8656e7a2 | 3567 | pr_warning("Could not create debugfs 'trace_pipe' entry\n"); |
b04cc6b1 FW |
3568 | |
3569 | /* per cpu trace */ | |
4acd4d00 | 3570 | entry = debugfs_create_file("trace", 0644, d_cpu, |
b04cc6b1 FW |
3571 | (void *) cpu, &tracing_fops); |
3572 | if (!entry) | |
8656e7a2 | 3573 | pr_warning("Could not create debugfs 'trace' entry\n"); |
7f96f93f SR |
3574 | |
3575 | entry = debugfs_create_file("trace_pipe_raw", 0444, d_cpu, | |
3576 | (void *) cpu, &tracing_buffers_fops); | |
3577 | if (!entry) | |
3578 | pr_warning("Could not create debugfs 'trace_pipe_raw' entry\n"); | |
b04cc6b1 FW |
3579 | } |
3580 | ||
60a11774 SR |
3581 | #ifdef CONFIG_FTRACE_SELFTEST |
3582 | /* Let selftest have access to static functions in this file */ | |
3583 | #include "trace_selftest.c" | |
3584 | #endif | |
3585 | ||
577b785f SR |
3586 | struct trace_option_dentry { |
3587 | struct tracer_opt *opt; | |
3588 | struct tracer_flags *flags; | |
3589 | struct dentry *entry; | |
3590 | }; | |
3591 | ||
3592 | static ssize_t | |
3593 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3594 | loff_t *ppos) | |
3595 | { | |
3596 | struct trace_option_dentry *topt = filp->private_data; | |
3597 | char *buf; | |
3598 | ||
3599 | if (topt->flags->val & topt->opt->bit) | |
3600 | buf = "1\n"; | |
3601 | else | |
3602 | buf = "0\n"; | |
3603 | ||
3604 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3605 | } | |
3606 | ||
3607 | static ssize_t | |
3608 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3609 | loff_t *ppos) | |
3610 | { | |
3611 | struct trace_option_dentry *topt = filp->private_data; | |
3612 | unsigned long val; | |
3613 | char buf[64]; | |
3614 | int ret; | |
3615 | ||
3616 | if (cnt >= sizeof(buf)) | |
3617 | return -EINVAL; | |
3618 | ||
3619 | if (copy_from_user(&buf, ubuf, cnt)) | |
3620 | return -EFAULT; | |
3621 | ||
3622 | buf[cnt] = 0; | |
3623 | ||
3624 | ret = strict_strtoul(buf, 10, &val); | |
3625 | if (ret < 0) | |
3626 | return ret; | |
3627 | ||
3628 | ret = 0; | |
3629 | switch (val) { | |
3630 | case 0: | |
3631 | /* do nothing if already cleared */ | |
3632 | if (!(topt->flags->val & topt->opt->bit)) | |
3633 | break; | |
3634 | ||
3635 | mutex_lock(&trace_types_lock); | |
3636 | if (current_trace->set_flag) | |
3637 | ret = current_trace->set_flag(topt->flags->val, | |
3638 | topt->opt->bit, 0); | |
3639 | mutex_unlock(&trace_types_lock); | |
3640 | if (ret) | |
3641 | return ret; | |
3642 | topt->flags->val &= ~topt->opt->bit; | |
3643 | break; | |
3644 | case 1: | |
3645 | /* do nothing if already set */ | |
3646 | if (topt->flags->val & topt->opt->bit) | |
3647 | break; | |
3648 | ||
3649 | mutex_lock(&trace_types_lock); | |
3650 | if (current_trace->set_flag) | |
3651 | ret = current_trace->set_flag(topt->flags->val, | |
3652 | topt->opt->bit, 1); | |
3653 | mutex_unlock(&trace_types_lock); | |
3654 | if (ret) | |
3655 | return ret; | |
3656 | topt->flags->val |= topt->opt->bit; | |
3657 | break; | |
3658 | ||
3659 | default: | |
3660 | return -EINVAL; | |
3661 | } | |
3662 | ||
3663 | *ppos += cnt; | |
3664 | ||
3665 | return cnt; | |
3666 | } | |
3667 | ||
3668 | ||
3669 | static const struct file_operations trace_options_fops = { | |
3670 | .open = tracing_open_generic, | |
3671 | .read = trace_options_read, | |
3672 | .write = trace_options_write, | |
3673 | }; | |
3674 | ||
a8259075 SR |
3675 | static ssize_t |
3676 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3677 | loff_t *ppos) | |
3678 | { | |
3679 | long index = (long)filp->private_data; | |
3680 | char *buf; | |
3681 | ||
3682 | if (trace_flags & (1 << index)) | |
3683 | buf = "1\n"; | |
3684 | else | |
3685 | buf = "0\n"; | |
3686 | ||
3687 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3688 | } | |
3689 | ||
3690 | static ssize_t | |
3691 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3692 | loff_t *ppos) | |
3693 | { | |
3694 | long index = (long)filp->private_data; | |
3695 | char buf[64]; | |
3696 | unsigned long val; | |
3697 | int ret; | |
3698 | ||
3699 | if (cnt >= sizeof(buf)) | |
3700 | return -EINVAL; | |
3701 | ||
3702 | if (copy_from_user(&buf, ubuf, cnt)) | |
3703 | return -EFAULT; | |
3704 | ||
3705 | buf[cnt] = 0; | |
3706 | ||
3707 | ret = strict_strtoul(buf, 10, &val); | |
3708 | if (ret < 0) | |
3709 | return ret; | |
3710 | ||
3711 | switch (val) { | |
3712 | case 0: | |
3713 | trace_flags &= ~(1 << index); | |
3714 | break; | |
3715 | case 1: | |
3716 | trace_flags |= 1 << index; | |
3717 | break; | |
3718 | ||
3719 | default: | |
3720 | return -EINVAL; | |
3721 | } | |
3722 | ||
3723 | *ppos += cnt; | |
3724 | ||
3725 | return cnt; | |
3726 | } | |
3727 | ||
a8259075 SR |
3728 | static const struct file_operations trace_options_core_fops = { |
3729 | .open = tracing_open_generic, | |
3730 | .read = trace_options_core_read, | |
3731 | .write = trace_options_core_write, | |
3732 | }; | |
3733 | ||
3734 | static struct dentry *trace_options_init_dentry(void) | |
3735 | { | |
3736 | struct dentry *d_tracer; | |
3737 | static struct dentry *t_options; | |
3738 | ||
3739 | if (t_options) | |
3740 | return t_options; | |
3741 | ||
3742 | d_tracer = tracing_init_dentry(); | |
3743 | if (!d_tracer) | |
3744 | return NULL; | |
3745 | ||
3746 | t_options = debugfs_create_dir("options", d_tracer); | |
3747 | if (!t_options) { | |
3748 | pr_warning("Could not create debugfs directory 'options'\n"); | |
3749 | return NULL; | |
3750 | } | |
3751 | ||
3752 | return t_options; | |
3753 | } | |
3754 | ||
577b785f SR |
3755 | static void |
3756 | create_trace_option_file(struct trace_option_dentry *topt, | |
3757 | struct tracer_flags *flags, | |
3758 | struct tracer_opt *opt) | |
3759 | { | |
3760 | struct dentry *t_options; | |
3761 | struct dentry *entry; | |
3762 | ||
3763 | t_options = trace_options_init_dentry(); | |
3764 | if (!t_options) | |
3765 | return; | |
3766 | ||
3767 | topt->flags = flags; | |
3768 | topt->opt = opt; | |
3769 | ||
3770 | entry = debugfs_create_file(opt->name, 0644, t_options, topt, | |
3771 | &trace_options_fops); | |
3772 | ||
3773 | topt->entry = entry; | |
3774 | ||
3775 | } | |
3776 | ||
3777 | static struct trace_option_dentry * | |
3778 | create_trace_option_files(struct tracer *tracer) | |
3779 | { | |
3780 | struct trace_option_dentry *topts; | |
3781 | struct tracer_flags *flags; | |
3782 | struct tracer_opt *opts; | |
3783 | int cnt; | |
3784 | ||
3785 | if (!tracer) | |
3786 | return NULL; | |
3787 | ||
3788 | flags = tracer->flags; | |
3789 | ||
3790 | if (!flags || !flags->opts) | |
3791 | return NULL; | |
3792 | ||
3793 | opts = flags->opts; | |
3794 | ||
3795 | for (cnt = 0; opts[cnt].name; cnt++) | |
3796 | ; | |
3797 | ||
0cfe8245 | 3798 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
3799 | if (!topts) |
3800 | return NULL; | |
3801 | ||
3802 | for (cnt = 0; opts[cnt].name; cnt++) | |
3803 | create_trace_option_file(&topts[cnt], flags, | |
3804 | &opts[cnt]); | |
3805 | ||
3806 | return topts; | |
3807 | } | |
3808 | ||
3809 | static void | |
3810 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
3811 | { | |
3812 | int cnt; | |
3813 | ||
3814 | if (!topts) | |
3815 | return; | |
3816 | ||
3817 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
3818 | if (topts[cnt].entry) | |
3819 | debugfs_remove(topts[cnt].entry); | |
3820 | } | |
3821 | ||
3822 | kfree(topts); | |
3823 | } | |
3824 | ||
a8259075 SR |
3825 | static struct dentry * |
3826 | create_trace_option_core_file(const char *option, long index) | |
3827 | { | |
3828 | struct dentry *t_options; | |
3829 | struct dentry *entry; | |
3830 | ||
3831 | t_options = trace_options_init_dentry(); | |
3832 | if (!t_options) | |
3833 | return NULL; | |
3834 | ||
3835 | entry = debugfs_create_file(option, 0644, t_options, (void *)index, | |
3836 | &trace_options_core_fops); | |
3837 | ||
3838 | return entry; | |
3839 | } | |
3840 | ||
3841 | static __init void create_trace_options_dir(void) | |
3842 | { | |
3843 | struct dentry *t_options; | |
3844 | struct dentry *entry; | |
3845 | int i; | |
3846 | ||
3847 | t_options = trace_options_init_dentry(); | |
3848 | if (!t_options) | |
3849 | return; | |
3850 | ||
3851 | for (i = 0; trace_options[i]; i++) { | |
3852 | entry = create_trace_option_core_file(trace_options[i], i); | |
3853 | if (!entry) | |
3854 | pr_warning("Could not create debugfs %s entry\n", | |
3855 | trace_options[i]); | |
3856 | } | |
3857 | } | |
3858 | ||
b5ad384e | 3859 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
3860 | { |
3861 | struct dentry *d_tracer; | |
3862 | struct dentry *entry; | |
b04cc6b1 | 3863 | int cpu; |
bc0c38d1 SR |
3864 | |
3865 | d_tracer = tracing_init_dentry(); | |
3866 | ||
3867 | entry = debugfs_create_file("tracing_enabled", 0644, d_tracer, | |
3868 | &global_trace, &tracing_ctrl_fops); | |
3869 | if (!entry) | |
3870 | pr_warning("Could not create debugfs 'tracing_enabled' entry\n"); | |
3871 | ||
ee6bce52 | 3872 | entry = debugfs_create_file("trace_options", 0644, d_tracer, |
bc0c38d1 SR |
3873 | NULL, &tracing_iter_fops); |
3874 | if (!entry) | |
ee6bce52 | 3875 | pr_warning("Could not create debugfs 'trace_options' entry\n"); |
bc0c38d1 | 3876 | |
a8259075 SR |
3877 | create_trace_options_dir(); |
3878 | ||
c7078de1 IM |
3879 | entry = debugfs_create_file("tracing_cpumask", 0644, d_tracer, |
3880 | NULL, &tracing_cpumask_fops); | |
3881 | if (!entry) | |
3882 | pr_warning("Could not create debugfs 'tracing_cpumask' entry\n"); | |
3883 | ||
4acd4d00 | 3884 | entry = debugfs_create_file("trace", 0644, d_tracer, |
b04cc6b1 | 3885 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); |
bc0c38d1 SR |
3886 | if (!entry) |
3887 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
3888 | ||
3889 | entry = debugfs_create_file("available_tracers", 0444, d_tracer, | |
3890 | &global_trace, &show_traces_fops); | |
3891 | if (!entry) | |
98a983aa | 3892 | pr_warning("Could not create debugfs 'available_tracers' entry\n"); |
bc0c38d1 SR |
3893 | |
3894 | entry = debugfs_create_file("current_tracer", 0444, d_tracer, | |
3895 | &global_trace, &set_tracer_fops); | |
3896 | if (!entry) | |
98a983aa | 3897 | pr_warning("Could not create debugfs 'current_tracer' entry\n"); |
bc0c38d1 SR |
3898 | |
3899 | entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer, | |
3900 | &tracing_max_latency, | |
3901 | &tracing_max_lat_fops); | |
3902 | if (!entry) | |
3903 | pr_warning("Could not create debugfs " | |
3904 | "'tracing_max_latency' entry\n"); | |
3905 | ||
3906 | entry = debugfs_create_file("tracing_thresh", 0644, d_tracer, | |
3907 | &tracing_thresh, &tracing_max_lat_fops); | |
3908 | if (!entry) | |
3909 | pr_warning("Could not create debugfs " | |
98a983aa | 3910 | "'tracing_thresh' entry\n"); |
7bd2f24c IM |
3911 | entry = debugfs_create_file("README", 0644, d_tracer, |
3912 | NULL, &tracing_readme_fops); | |
3913 | if (!entry) | |
3914 | pr_warning("Could not create debugfs 'README' entry\n"); | |
3915 | ||
b04cc6b1 FW |
3916 | entry = debugfs_create_file("trace_pipe", 0444, d_tracer, |
3917 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); | |
b3806b43 SR |
3918 | if (!entry) |
3919 | pr_warning("Could not create debugfs " | |
98a983aa | 3920 | "'trace_pipe' entry\n"); |
bc0c38d1 | 3921 | |
a94c80e7 | 3922 | entry = debugfs_create_file("buffer_size_kb", 0644, d_tracer, |
a98a3c3f SR |
3923 | &global_trace, &tracing_entries_fops); |
3924 | if (!entry) | |
3925 | pr_warning("Could not create debugfs " | |
a94c80e7 | 3926 | "'buffer_size_kb' entry\n"); |
a98a3c3f | 3927 | |
5bf9a1ee PP |
3928 | entry = debugfs_create_file("trace_marker", 0220, d_tracer, |
3929 | NULL, &tracing_mark_fops); | |
3930 | if (!entry) | |
3931 | pr_warning("Could not create debugfs " | |
3932 | "'trace_marker' entry\n"); | |
3933 | ||
bc0c38d1 SR |
3934 | #ifdef CONFIG_DYNAMIC_FTRACE |
3935 | entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer, | |
3936 | &ftrace_update_tot_cnt, | |
b807c3d0 | 3937 | &tracing_dyn_info_fops); |
bc0c38d1 SR |
3938 | if (!entry) |
3939 | pr_warning("Could not create debugfs " | |
3940 | "'dyn_ftrace_total_info' entry\n"); | |
3941 | #endif | |
d618b3e6 IM |
3942 | #ifdef CONFIG_SYSPROF_TRACER |
3943 | init_tracer_sysprof_debugfs(d_tracer); | |
3944 | #endif | |
b04cc6b1 FW |
3945 | |
3946 | for_each_tracing_cpu(cpu) | |
3947 | tracing_init_debugfs_percpu(cpu); | |
3948 | ||
b5ad384e | 3949 | return 0; |
bc0c38d1 SR |
3950 | } |
3951 | ||
3f5a54e3 SR |
3952 | static int trace_panic_handler(struct notifier_block *this, |
3953 | unsigned long event, void *unused) | |
3954 | { | |
944ac425 SR |
3955 | if (ftrace_dump_on_oops) |
3956 | ftrace_dump(); | |
3f5a54e3 SR |
3957 | return NOTIFY_OK; |
3958 | } | |
3959 | ||
3960 | static struct notifier_block trace_panic_notifier = { | |
3961 | .notifier_call = trace_panic_handler, | |
3962 | .next = NULL, | |
3963 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
3964 | }; | |
3965 | ||
3966 | static int trace_die_handler(struct notifier_block *self, | |
3967 | unsigned long val, | |
3968 | void *data) | |
3969 | { | |
3970 | switch (val) { | |
3971 | case DIE_OOPS: | |
944ac425 SR |
3972 | if (ftrace_dump_on_oops) |
3973 | ftrace_dump(); | |
3f5a54e3 SR |
3974 | break; |
3975 | default: | |
3976 | break; | |
3977 | } | |
3978 | return NOTIFY_OK; | |
3979 | } | |
3980 | ||
3981 | static struct notifier_block trace_die_notifier = { | |
3982 | .notifier_call = trace_die_handler, | |
3983 | .priority = 200 | |
3984 | }; | |
3985 | ||
3986 | /* | |
3987 | * printk is set to max of 1024, we really don't need it that big. | |
3988 | * Nothing should be printing 1000 characters anyway. | |
3989 | */ | |
3990 | #define TRACE_MAX_PRINT 1000 | |
3991 | ||
3992 | /* | |
3993 | * Define here KERN_TRACE so that we have one place to modify | |
3994 | * it if we decide to change what log level the ftrace dump | |
3995 | * should be at. | |
3996 | */ | |
428aee14 | 3997 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
3998 | |
3999 | static void | |
4000 | trace_printk_seq(struct trace_seq *s) | |
4001 | { | |
4002 | /* Probably should print a warning here. */ | |
4003 | if (s->len >= 1000) | |
4004 | s->len = 1000; | |
4005 | ||
4006 | /* should be zero ended, but we are paranoid. */ | |
4007 | s->buffer[s->len] = 0; | |
4008 | ||
4009 | printk(KERN_TRACE "%s", s->buffer); | |
4010 | ||
f9520750 | 4011 | trace_seq_init(s); |
3f5a54e3 SR |
4012 | } |
4013 | ||
cf586b61 | 4014 | static void __ftrace_dump(bool disable_tracing) |
3f5a54e3 SR |
4015 | { |
4016 | static DEFINE_SPINLOCK(ftrace_dump_lock); | |
4017 | /* use static because iter can be a bit big for the stack */ | |
4018 | static struct trace_iterator iter; | |
cf586b61 | 4019 | unsigned int old_userobj; |
3f5a54e3 | 4020 | static int dump_ran; |
d769041f SR |
4021 | unsigned long flags; |
4022 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4023 | |
4024 | /* only one dump */ | |
4025 | spin_lock_irqsave(&ftrace_dump_lock, flags); | |
4026 | if (dump_ran) | |
4027 | goto out; | |
4028 | ||
4029 | dump_ran = 1; | |
4030 | ||
0ee6b6cf | 4031 | tracing_off(); |
cf586b61 FW |
4032 | |
4033 | if (disable_tracing) | |
4034 | ftrace_kill(); | |
3f5a54e3 | 4035 | |
d769041f SR |
4036 | for_each_tracing_cpu(cpu) { |
4037 | atomic_inc(&global_trace.data[cpu]->disabled); | |
4038 | } | |
4039 | ||
cf586b61 FW |
4040 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4041 | ||
b54d3de9 TE |
4042 | /* don't look at user memory in panic mode */ |
4043 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4044 | ||
3f5a54e3 SR |
4045 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
4046 | ||
e543ad76 | 4047 | /* Simulate the iterator */ |
3f5a54e3 SR |
4048 | iter.tr = &global_trace; |
4049 | iter.trace = current_trace; | |
e543ad76 | 4050 | iter.cpu_file = TRACE_PIPE_ALL_CPU; |
3f5a54e3 SR |
4051 | |
4052 | /* | |
4053 | * We need to stop all tracing on all CPUS to read the | |
4054 | * the next buffer. This is a bit expensive, but is | |
4055 | * not done often. We fill all what we can read, | |
4056 | * and then release the locks again. | |
4057 | */ | |
4058 | ||
3f5a54e3 SR |
4059 | while (!trace_empty(&iter)) { |
4060 | ||
4061 | if (!cnt) | |
4062 | printk(KERN_TRACE "---------------------------------\n"); | |
4063 | ||
4064 | cnt++; | |
4065 | ||
4066 | /* reset all but tr, trace, and overruns */ | |
4067 | memset(&iter.seq, 0, | |
4068 | sizeof(struct trace_iterator) - | |
4069 | offsetof(struct trace_iterator, seq)); | |
4070 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4071 | iter.pos = -1; | |
4072 | ||
4073 | if (find_next_entry_inc(&iter) != NULL) { | |
4074 | print_trace_line(&iter); | |
4075 | trace_consume(&iter); | |
4076 | } | |
4077 | ||
4078 | trace_printk_seq(&iter.seq); | |
4079 | } | |
4080 | ||
4081 | if (!cnt) | |
4082 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4083 | else | |
4084 | printk(KERN_TRACE "---------------------------------\n"); | |
4085 | ||
cf586b61 FW |
4086 | /* Re-enable tracing if requested */ |
4087 | if (!disable_tracing) { | |
4088 | trace_flags |= old_userobj; | |
4089 | ||
4090 | for_each_tracing_cpu(cpu) { | |
4091 | atomic_dec(&global_trace.data[cpu]->disabled); | |
4092 | } | |
4093 | tracing_on(); | |
4094 | } | |
4095 | ||
3f5a54e3 SR |
4096 | out: |
4097 | spin_unlock_irqrestore(&ftrace_dump_lock, flags); | |
4098 | } | |
4099 | ||
cf586b61 FW |
4100 | /* By default: disable tracing after the dump */ |
4101 | void ftrace_dump(void) | |
4102 | { | |
4103 | __ftrace_dump(true); | |
4104 | } | |
4105 | ||
3928a8a2 | 4106 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4107 | { |
4c11d7ae | 4108 | struct trace_array_cpu *data; |
73c5162a | 4109 | int ring_buf_size; |
4c11d7ae | 4110 | int i; |
9e01c1b7 | 4111 | int ret = -ENOMEM; |
4c11d7ae | 4112 | |
9e01c1b7 RR |
4113 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4114 | goto out; | |
4115 | ||
4116 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4117 | goto out_free_buffer_mask; | |
4c11d7ae | 4118 | |
b04cc6b1 FW |
4119 | if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) |
4120 | goto out_free_tracing_cpumask; | |
4121 | ||
73c5162a SR |
4122 | /* To save memory, keep the ring buffer size to its minimum */ |
4123 | if (ring_buffer_expanded) | |
4124 | ring_buf_size = trace_buf_size; | |
4125 | else | |
4126 | ring_buf_size = 1; | |
4127 | ||
9e01c1b7 RR |
4128 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4129 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
b04cc6b1 | 4130 | cpumask_clear(tracing_reader_cpumask); |
9e01c1b7 RR |
4131 | |
4132 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
73c5162a | 4133 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4134 | TRACE_BUFFER_FLAGS); |
4135 | if (!global_trace.buffer) { | |
4136 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4137 | WARN_ON(1); | |
9e01c1b7 | 4138 | goto out_free_cpumask; |
4c11d7ae | 4139 | } |
3928a8a2 | 4140 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4141 | |
9e01c1b7 | 4142 | |
4c11d7ae | 4143 | #ifdef CONFIG_TRACER_MAX_TRACE |
73c5162a | 4144 | max_tr.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4145 | TRACE_BUFFER_FLAGS); |
4146 | if (!max_tr.buffer) { | |
4147 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4148 | WARN_ON(1); | |
4149 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4150 | goto out_free_cpumask; |
4c11d7ae | 4151 | } |
3928a8a2 SR |
4152 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
4153 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 4154 | #endif |
ab46428c | 4155 | |
4c11d7ae | 4156 | /* Allocate the first page for all buffers */ |
ab46428c | 4157 | for_each_tracing_cpu(i) { |
4c11d7ae | 4158 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 | 4159 | max_tr.data[i] = &per_cpu(max_data, i); |
4c11d7ae | 4160 | } |
bc0c38d1 | 4161 | |
bc0c38d1 SR |
4162 | trace_init_cmdlines(); |
4163 | ||
43a15386 | 4164 | register_tracer(&nop_trace); |
79fb0768 | 4165 | current_trace = &nop_trace; |
b5ad384e FW |
4166 | #ifdef CONFIG_BOOT_TRACER |
4167 | register_tracer(&boot_tracer); | |
b5ad384e | 4168 | #endif |
60a11774 SR |
4169 | /* All seems OK, enable tracing */ |
4170 | tracing_disabled = 0; | |
3928a8a2 | 4171 | |
3f5a54e3 SR |
4172 | atomic_notifier_chain_register(&panic_notifier_list, |
4173 | &trace_panic_notifier); | |
4174 | ||
4175 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4176 | |
4177 | return 0; | |
3f5a54e3 | 4178 | |
9e01c1b7 | 4179 | out_free_cpumask: |
b04cc6b1 FW |
4180 | free_cpumask_var(tracing_reader_cpumask); |
4181 | out_free_tracing_cpumask: | |
9e01c1b7 RR |
4182 | free_cpumask_var(tracing_cpumask); |
4183 | out_free_buffer_mask: | |
4184 | free_cpumask_var(tracing_buffer_mask); | |
4185 | out: | |
4186 | return ret; | |
bc0c38d1 | 4187 | } |
b2821ae6 SR |
4188 | |
4189 | __init static int clear_boot_tracer(void) | |
4190 | { | |
4191 | /* | |
4192 | * The default tracer at boot buffer is an init section. | |
4193 | * This function is called in lateinit. If we did not | |
4194 | * find the boot tracer, then clear it out, to prevent | |
4195 | * later registration from accessing the buffer that is | |
4196 | * about to be freed. | |
4197 | */ | |
4198 | if (!default_bootup_tracer) | |
4199 | return 0; | |
4200 | ||
4201 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4202 | default_bootup_tracer); | |
4203 | default_bootup_tracer = NULL; | |
4204 | ||
4205 | return 0; | |
4206 | } | |
4207 | ||
b5ad384e FW |
4208 | early_initcall(tracer_alloc_buffers); |
4209 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4210 | late_initcall(clear_boot_tracer); |