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> | |
405f5571 | 20 | #include <linux/smp_lock.h> |
3f5a54e3 | 21 | #include <linux/notifier.h> |
2cadf913 | 22 | #include <linux/irqflags.h> |
bc0c38d1 | 23 | #include <linux/debugfs.h> |
4c11d7ae | 24 | #include <linux/pagemap.h> |
bc0c38d1 SR |
25 | #include <linux/hardirq.h> |
26 | #include <linux/linkage.h> | |
27 | #include <linux/uaccess.h> | |
2cadf913 | 28 | #include <linux/kprobes.h> |
bc0c38d1 SR |
29 | #include <linux/ftrace.h> |
30 | #include <linux/module.h> | |
31 | #include <linux/percpu.h> | |
2cadf913 | 32 | #include <linux/splice.h> |
3f5a54e3 | 33 | #include <linux/kdebug.h> |
5f0c6c03 | 34 | #include <linux/string.h> |
bc0c38d1 SR |
35 | #include <linux/ctype.h> |
36 | #include <linux/init.h> | |
2a2cc8f7 | 37 | #include <linux/poll.h> |
bc0c38d1 SR |
38 | #include <linux/gfp.h> |
39 | #include <linux/fs.h> | |
86387f7e | 40 | |
bc0c38d1 | 41 | #include "trace.h" |
f0868d1e | 42 | #include "trace_output.h" |
bc0c38d1 | 43 | |
3928a8a2 SR |
44 | #define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE) |
45 | ||
73c5162a SR |
46 | /* |
47 | * On boot up, the ring buffer is set to the minimum size, so that | |
48 | * we do not waste memory on systems that are not using tracing. | |
49 | */ | |
020e5f85 | 50 | int ring_buffer_expanded; |
73c5162a | 51 | |
8e1b82e0 FW |
52 | /* |
53 | * We need to change this state when a selftest is running. | |
ff32504f FW |
54 | * A selftest will lurk into the ring-buffer to count the |
55 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 56 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
57 | * at the same time, giving false positive or negative results. |
58 | */ | |
8e1b82e0 | 59 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 60 | |
b2821ae6 SR |
61 | /* |
62 | * If a tracer is running, we do not want to run SELFTEST. | |
63 | */ | |
020e5f85 | 64 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 65 | |
adf9f195 FW |
66 | /* For tracers that don't implement custom flags */ |
67 | static struct tracer_opt dummy_tracer_opt[] = { | |
68 | { } | |
69 | }; | |
70 | ||
71 | static struct tracer_flags dummy_tracer_flags = { | |
72 | .val = 0, | |
73 | .opts = dummy_tracer_opt | |
74 | }; | |
75 | ||
76 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
77 | { | |
78 | return 0; | |
79 | } | |
0f048701 SR |
80 | |
81 | /* | |
82 | * Kill all tracing for good (never come back). | |
83 | * It is initialized to 1 but will turn to zero if the initialization | |
84 | * of the tracer is successful. But that is the only place that sets | |
85 | * this back to zero. | |
86 | */ | |
4fd27358 | 87 | static int tracing_disabled = 1; |
0f048701 | 88 | |
5e5bf483 | 89 | DEFINE_PER_CPU(local_t, ftrace_cpu_disabled); |
d769041f SR |
90 | |
91 | static inline void ftrace_disable_cpu(void) | |
92 | { | |
93 | preempt_disable(); | |
94 | local_inc(&__get_cpu_var(ftrace_cpu_disabled)); | |
95 | } | |
96 | ||
97 | static inline void ftrace_enable_cpu(void) | |
98 | { | |
99 | local_dec(&__get_cpu_var(ftrace_cpu_disabled)); | |
100 | preempt_enable(); | |
101 | } | |
102 | ||
9e01c1b7 | 103 | static cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 104 | |
b04cc6b1 FW |
105 | /* Define which cpu buffers are currently read in trace_pipe */ |
106 | static cpumask_var_t tracing_reader_cpumask; | |
107 | ||
ab46428c | 108 | #define for_each_tracing_cpu(cpu) \ |
9e01c1b7 | 109 | for_each_cpu(cpu, tracing_buffer_mask) |
ab46428c | 110 | |
944ac425 SR |
111 | /* |
112 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
113 | * | |
114 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
115 | * is set, then ftrace_dump is called. This will output the contents | |
116 | * of the ftrace buffers to the console. This is very useful for | |
117 | * capturing traces that lead to crashes and outputing it to a | |
118 | * serial console. | |
119 | * | |
120 | * It is default off, but you can enable it with either specifying | |
121 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
122 | * /proc/sys/kernel/ftrace_dump_on_oops to true. | |
123 | */ | |
124 | int ftrace_dump_on_oops; | |
125 | ||
b2821ae6 SR |
126 | static int tracing_set_tracer(const char *buf); |
127 | ||
128 | #define BOOTUP_TRACER_SIZE 100 | |
129 | static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata; | |
130 | static char *default_bootup_tracer; | |
d9e54076 PZ |
131 | |
132 | static int __init set_ftrace(char *str) | |
133 | { | |
b2821ae6 SR |
134 | strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); |
135 | default_bootup_tracer = bootup_tracer_buf; | |
73c5162a SR |
136 | /* We are using ftrace early, expand it */ |
137 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
138 | return 1; |
139 | } | |
b2821ae6 | 140 | __setup("ftrace=", set_ftrace); |
d9e54076 | 141 | |
944ac425 SR |
142 | static int __init set_ftrace_dump_on_oops(char *str) |
143 | { | |
144 | ftrace_dump_on_oops = 1; | |
145 | return 1; | |
146 | } | |
147 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 148 | |
cf8e3474 | 149 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
150 | { |
151 | nsec += 500; | |
152 | do_div(nsec, 1000); | |
153 | return nsec; | |
154 | } | |
155 | ||
4fcdae83 SR |
156 | /* |
157 | * The global_trace is the descriptor that holds the tracing | |
158 | * buffers for the live tracing. For each CPU, it contains | |
159 | * a link list of pages that will store trace entries. The | |
160 | * page descriptor of the pages in the memory is used to hold | |
161 | * the link list by linking the lru item in the page descriptor | |
162 | * to each of the pages in the buffer per CPU. | |
163 | * | |
164 | * For each active CPU there is a data field that holds the | |
165 | * pages for the buffer for that CPU. Each CPU has the same number | |
166 | * of pages allocated for its buffer. | |
167 | */ | |
bc0c38d1 SR |
168 | static struct trace_array global_trace; |
169 | ||
170 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
171 | ||
eb02ce01 TZ |
172 | int filter_current_check_discard(struct ftrace_event_call *call, void *rec, |
173 | struct ring_buffer_event *event) | |
174 | { | |
175 | return filter_check_discard(call, rec, global_trace.buffer, event); | |
176 | } | |
17c873ec | 177 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 178 | |
37886f6a SR |
179 | cycle_t ftrace_now(int cpu) |
180 | { | |
181 | u64 ts; | |
182 | ||
183 | /* Early boot up does not have a buffer yet */ | |
184 | if (!global_trace.buffer) | |
185 | return trace_clock_local(); | |
186 | ||
187 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
188 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
189 | ||
190 | return ts; | |
191 | } | |
bc0c38d1 | 192 | |
4fcdae83 SR |
193 | /* |
194 | * The max_tr is used to snapshot the global_trace when a maximum | |
195 | * latency is reached. Some tracers will use this to store a maximum | |
196 | * trace while it continues examining live traces. | |
197 | * | |
198 | * The buffers for the max_tr are set up the same as the global_trace. | |
199 | * When a snapshot is taken, the link list of the max_tr is swapped | |
200 | * with the link list of the global_trace and the buffers are reset for | |
201 | * the global_trace so the tracing can continue. | |
202 | */ | |
bc0c38d1 SR |
203 | static struct trace_array max_tr; |
204 | ||
205 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
206 | ||
4fcdae83 | 207 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 208 | static int tracer_enabled = 1; |
4fcdae83 | 209 | |
9036990d SR |
210 | /** |
211 | * tracing_is_enabled - return tracer_enabled status | |
212 | * | |
213 | * This function is used by other tracers to know the status | |
214 | * of the tracer_enabled flag. Tracers may use this function | |
215 | * to know if it should enable their features when starting | |
216 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
217 | */ | |
218 | int tracing_is_enabled(void) | |
219 | { | |
220 | return tracer_enabled; | |
221 | } | |
222 | ||
4fcdae83 | 223 | /* |
3928a8a2 SR |
224 | * trace_buf_size is the size in bytes that is allocated |
225 | * for a buffer. Note, the number of bytes is always rounded | |
226 | * to page size. | |
3f5a54e3 SR |
227 | * |
228 | * This number is purposely set to a low number of 16384. | |
229 | * If the dump on oops happens, it will be much appreciated | |
230 | * to not have to wait for all that output. Anyway this can be | |
231 | * boot time and run time configurable. | |
4fcdae83 | 232 | */ |
3928a8a2 | 233 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 234 | |
3928a8a2 | 235 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 236 | |
4fcdae83 | 237 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 238 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
239 | |
240 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 241 | static struct tracer *current_trace __read_mostly; |
4fcdae83 SR |
242 | |
243 | /* | |
244 | * max_tracer_type_len is used to simplify the allocating of | |
245 | * buffers to read userspace tracer names. We keep track of | |
246 | * the longest tracer name registered. | |
247 | */ | |
bc0c38d1 SR |
248 | static int max_tracer_type_len; |
249 | ||
4fcdae83 SR |
250 | /* |
251 | * trace_types_lock is used to protect the trace_types list. | |
252 | * This lock is also used to keep user access serialized. | |
253 | * Accesses from userspace will grab this lock while userspace | |
254 | * activities happen inside the kernel. | |
255 | */ | |
bc0c38d1 | 256 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
257 | |
258 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
259 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
260 | ||
ee6bce52 | 261 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 262 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a SR |
263 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
264 | TRACE_ITER_GRAPH_TIME; | |
4e655519 | 265 | |
b8de7bd1 SR |
266 | static int trace_stop_count; |
267 | static DEFINE_SPINLOCK(tracing_start_lock); | |
268 | ||
4fcdae83 SR |
269 | /** |
270 | * trace_wake_up - wake up tasks waiting for trace input | |
271 | * | |
272 | * Simply wakes up any task that is blocked on the trace_wait | |
273 | * queue. These is used with trace_poll for tasks polling the trace. | |
274 | */ | |
4e655519 IM |
275 | void trace_wake_up(void) |
276 | { | |
017730c1 IM |
277 | /* |
278 | * The runqueue_is_locked() can fail, but this is the best we | |
279 | * have for now: | |
280 | */ | |
281 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
282 | wake_up(&trace_wait); |
283 | } | |
bc0c38d1 | 284 | |
3928a8a2 | 285 | static int __init set_buf_size(char *str) |
bc0c38d1 | 286 | { |
3928a8a2 | 287 | unsigned long buf_size; |
c6caeeb1 | 288 | |
bc0c38d1 SR |
289 | if (!str) |
290 | return 0; | |
9d612bef | 291 | buf_size = memparse(str, &str); |
c6caeeb1 | 292 | /* nr_entries can not be zero */ |
9d612bef | 293 | if (buf_size == 0) |
c6caeeb1 | 294 | return 0; |
3928a8a2 | 295 | trace_buf_size = buf_size; |
bc0c38d1 SR |
296 | return 1; |
297 | } | |
3928a8a2 | 298 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 299 | |
57f50be1 SR |
300 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
301 | { | |
302 | return nsecs / 1000; | |
303 | } | |
304 | ||
4fcdae83 | 305 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
306 | static const char *trace_options[] = { |
307 | "print-parent", | |
308 | "sym-offset", | |
309 | "sym-addr", | |
310 | "verbose", | |
f9896bf3 | 311 | "raw", |
5e3ca0ec | 312 | "hex", |
cb0f12aa | 313 | "bin", |
2a2cc8f7 | 314 | "block", |
86387f7e | 315 | "stacktrace", |
4ac3ba41 | 316 | "sched-tree", |
5e1607a0 | 317 | "trace_printk", |
b2a866f9 | 318 | "ftrace_preempt", |
9f029e83 | 319 | "branch", |
12ef7d44 | 320 | "annotate", |
02b67518 | 321 | "userstacktrace", |
b54d3de9 | 322 | "sym-userobj", |
66896a85 | 323 | "printk-msg-only", |
c4a8e8be | 324 | "context-info", |
c032ef64 | 325 | "latency-format", |
be6f164a | 326 | "sleep-time", |
a2a16d6a | 327 | "graph-time", |
bc0c38d1 SR |
328 | NULL |
329 | }; | |
330 | ||
5079f326 Z |
331 | static struct { |
332 | u64 (*func)(void); | |
333 | const char *name; | |
334 | } trace_clocks[] = { | |
335 | { trace_clock_local, "local" }, | |
336 | { trace_clock_global, "global" }, | |
337 | }; | |
338 | ||
339 | int trace_clock_id; | |
340 | ||
6c6c2796 PP |
341 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
342 | { | |
343 | int len; | |
344 | int ret; | |
345 | ||
2dc5d12b SR |
346 | if (!cnt) |
347 | return 0; | |
348 | ||
6c6c2796 PP |
349 | if (s->len <= s->readpos) |
350 | return -EBUSY; | |
351 | ||
352 | len = s->len - s->readpos; | |
353 | if (cnt > len) | |
354 | cnt = len; | |
355 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 356 | if (ret == cnt) |
6c6c2796 PP |
357 | return -EFAULT; |
358 | ||
2dc5d12b SR |
359 | cnt -= ret; |
360 | ||
e74da523 | 361 | s->readpos += cnt; |
6c6c2796 | 362 | return cnt; |
214023c3 SR |
363 | } |
364 | ||
b8b94265 | 365 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
366 | { |
367 | int len; | |
368 | void *ret; | |
369 | ||
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 = memcpy(buf, s->buffer + s->readpos, cnt); | |
377 | if (!ret) | |
378 | return -EFAULT; | |
379 | ||
e74da523 | 380 | s->readpos += cnt; |
3c56819b EGM |
381 | return cnt; |
382 | } | |
383 | ||
5d4a9dba SR |
384 | /* |
385 | * ftrace_max_lock is used to protect the swapping of buffers | |
386 | * when taking a max snapshot. The buffers themselves are | |
387 | * protected by per_cpu spinlocks. But the action of the swap | |
388 | * needs its own lock. | |
389 | * | |
390 | * This is defined as a raw_spinlock_t in order to help | |
391 | * with performance when lockdep debugging is enabled. | |
392 | * | |
393 | * It is also used in other places outside the update_max_tr | |
394 | * so it needs to be defined outside of the | |
395 | * CONFIG_TRACER_MAX_TRACE. | |
396 | */ | |
397 | static raw_spinlock_t ftrace_max_lock = | |
398 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
399 | ||
400 | #ifdef CONFIG_TRACER_MAX_TRACE | |
401 | unsigned long __read_mostly tracing_max_latency; | |
402 | unsigned long __read_mostly tracing_thresh; | |
403 | ||
404 | /* | |
405 | * Copy the new maximum trace into the separate maximum-trace | |
406 | * structure. (this way the maximum trace is permanently saved, | |
407 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
408 | */ | |
409 | static void | |
410 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
411 | { | |
412 | struct trace_array_cpu *data = tr->data[cpu]; | |
8248ac05 | 413 | struct trace_array_cpu *max_data = tr->data[cpu]; |
5d4a9dba SR |
414 | |
415 | max_tr.cpu = cpu; | |
416 | max_tr.time_start = data->preempt_timestamp; | |
417 | ||
8248ac05 SR |
418 | max_data = max_tr.data[cpu]; |
419 | max_data->saved_latency = tracing_max_latency; | |
420 | max_data->critical_start = data->critical_start; | |
421 | max_data->critical_end = data->critical_end; | |
5d4a9dba SR |
422 | |
423 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
8248ac05 SR |
424 | max_data->pid = tsk->pid; |
425 | max_data->uid = task_uid(tsk); | |
426 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
427 | max_data->policy = tsk->policy; | |
428 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
429 | |
430 | /* record this tasks comm */ | |
431 | tracing_record_cmdline(tsk); | |
432 | } | |
433 | ||
4fcdae83 SR |
434 | /** |
435 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
436 | * @tr: tracer | |
437 | * @tsk: the task with the latency | |
438 | * @cpu: The cpu that initiated the trace. | |
439 | * | |
440 | * Flip the buffers between the @tr and the max_tr and record information | |
441 | * about which task was the cause of this latency. | |
442 | */ | |
e309b41d | 443 | void |
bc0c38d1 SR |
444 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
445 | { | |
3928a8a2 | 446 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 447 | |
b8de7bd1 SR |
448 | if (trace_stop_count) |
449 | return; | |
450 | ||
4c11d7ae | 451 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 452 | __raw_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
453 | |
454 | tr->buffer = max_tr.buffer; | |
455 | max_tr.buffer = buf; | |
456 | ||
d769041f | 457 | ftrace_disable_cpu(); |
3928a8a2 | 458 | ring_buffer_reset(tr->buffer); |
d769041f | 459 | ftrace_enable_cpu(); |
bc0c38d1 SR |
460 | |
461 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 462 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
463 | } |
464 | ||
465 | /** | |
466 | * update_max_tr_single - only copy one trace over, and reset the rest | |
467 | * @tr - tracer | |
468 | * @tsk - task with the latency | |
469 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
470 | * |
471 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 472 | */ |
e309b41d | 473 | void |
bc0c38d1 SR |
474 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
475 | { | |
3928a8a2 | 476 | int ret; |
bc0c38d1 | 477 | |
b8de7bd1 SR |
478 | if (trace_stop_count) |
479 | return; | |
480 | ||
4c11d7ae | 481 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 482 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 483 | |
d769041f SR |
484 | ftrace_disable_cpu(); |
485 | ||
3928a8a2 SR |
486 | ring_buffer_reset(max_tr.buffer); |
487 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); | |
488 | ||
d769041f SR |
489 | ftrace_enable_cpu(); |
490 | ||
97b17efe | 491 | WARN_ON_ONCE(ret && ret != -EAGAIN); |
bc0c38d1 SR |
492 | |
493 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 494 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 495 | } |
5d4a9dba | 496 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 497 | |
4fcdae83 SR |
498 | /** |
499 | * register_tracer - register a tracer with the ftrace system. | |
500 | * @type - the plugin for the tracer | |
501 | * | |
502 | * Register a new plugin tracer. | |
503 | */ | |
bc0c38d1 | 504 | int register_tracer(struct tracer *type) |
e7669b8e HE |
505 | __releases(kernel_lock) |
506 | __acquires(kernel_lock) | |
bc0c38d1 SR |
507 | { |
508 | struct tracer *t; | |
509 | int len; | |
510 | int ret = 0; | |
511 | ||
512 | if (!type->name) { | |
513 | pr_info("Tracer must have a name\n"); | |
514 | return -1; | |
515 | } | |
516 | ||
86fa2f60 IM |
517 | /* |
518 | * When this gets called we hold the BKL which means that | |
519 | * preemption is disabled. Various trace selftests however | |
520 | * need to disable and enable preemption for successful tests. | |
521 | * So we drop the BKL here and grab it after the tests again. | |
522 | */ | |
523 | unlock_kernel(); | |
bc0c38d1 | 524 | mutex_lock(&trace_types_lock); |
86fa2f60 | 525 | |
8e1b82e0 FW |
526 | tracing_selftest_running = true; |
527 | ||
bc0c38d1 SR |
528 | for (t = trace_types; t; t = t->next) { |
529 | if (strcmp(type->name, t->name) == 0) { | |
530 | /* already found */ | |
531 | pr_info("Trace %s already registered\n", | |
532 | type->name); | |
533 | ret = -1; | |
534 | goto out; | |
535 | } | |
536 | } | |
537 | ||
adf9f195 FW |
538 | if (!type->set_flag) |
539 | type->set_flag = &dummy_set_flag; | |
540 | if (!type->flags) | |
541 | type->flags = &dummy_tracer_flags; | |
542 | else | |
543 | if (!type->flags->opts) | |
544 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
545 | if (!type->wait_pipe) |
546 | type->wait_pipe = default_wait_pipe; | |
547 | ||
adf9f195 | 548 | |
60a11774 | 549 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 550 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 551 | struct tracer *saved_tracer = current_trace; |
60a11774 | 552 | struct trace_array *tr = &global_trace; |
ff32504f | 553 | |
60a11774 SR |
554 | /* |
555 | * Run a selftest on this tracer. | |
556 | * Here we reset the trace buffer, and set the current | |
557 | * tracer to be this tracer. The tracer can then run some | |
558 | * internal tracing to verify that everything is in order. | |
559 | * If we fail, we do not register this tracer. | |
560 | */ | |
76f0d073 | 561 | tracing_reset_online_cpus(tr); |
86fa2f60 | 562 | |
60a11774 | 563 | current_trace = type; |
60a11774 SR |
564 | /* the test is responsible for initializing and enabling */ |
565 | pr_info("Testing tracer %s: ", type->name); | |
566 | ret = type->selftest(type, tr); | |
567 | /* the test is responsible for resetting too */ | |
568 | current_trace = saved_tracer; | |
60a11774 SR |
569 | if (ret) { |
570 | printk(KERN_CONT "FAILED!\n"); | |
571 | goto out; | |
572 | } | |
1d4db00a | 573 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 574 | tracing_reset_online_cpus(tr); |
86fa2f60 | 575 | |
60a11774 SR |
576 | printk(KERN_CONT "PASSED\n"); |
577 | } | |
578 | #endif | |
579 | ||
bc0c38d1 SR |
580 | type->next = trace_types; |
581 | trace_types = type; | |
582 | len = strlen(type->name); | |
583 | if (len > max_tracer_type_len) | |
584 | max_tracer_type_len = len; | |
60a11774 | 585 | |
bc0c38d1 | 586 | out: |
8e1b82e0 | 587 | tracing_selftest_running = false; |
bc0c38d1 SR |
588 | mutex_unlock(&trace_types_lock); |
589 | ||
dac74940 SR |
590 | if (ret || !default_bootup_tracer) |
591 | goto out_unlock; | |
592 | ||
593 | if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE)) | |
594 | goto out_unlock; | |
595 | ||
596 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
597 | /* Do we want this tracer to start on bootup? */ | |
598 | tracing_set_tracer(type->name); | |
599 | default_bootup_tracer = NULL; | |
600 | /* disable other selftests, since this will break it. */ | |
601 | tracing_selftest_disabled = 1; | |
b2821ae6 | 602 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
603 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
604 | type->name); | |
b2821ae6 | 605 | #endif |
b2821ae6 | 606 | |
dac74940 | 607 | out_unlock: |
b2821ae6 | 608 | lock_kernel(); |
bc0c38d1 SR |
609 | return ret; |
610 | } | |
611 | ||
612 | void unregister_tracer(struct tracer *type) | |
613 | { | |
614 | struct tracer **t; | |
615 | int len; | |
616 | ||
617 | mutex_lock(&trace_types_lock); | |
618 | for (t = &trace_types; *t; t = &(*t)->next) { | |
619 | if (*t == type) | |
620 | goto found; | |
621 | } | |
622 | pr_info("Trace %s not registered\n", type->name); | |
623 | goto out; | |
624 | ||
625 | found: | |
626 | *t = (*t)->next; | |
b5db03c4 ACM |
627 | |
628 | if (type == current_trace && tracer_enabled) { | |
629 | tracer_enabled = 0; | |
630 | tracing_stop(); | |
631 | if (current_trace->stop) | |
632 | current_trace->stop(&global_trace); | |
633 | current_trace = &nop_trace; | |
634 | } | |
635 | ||
bc0c38d1 SR |
636 | if (strlen(type->name) != max_tracer_type_len) |
637 | goto out; | |
638 | ||
639 | max_tracer_type_len = 0; | |
640 | for (t = &trace_types; *t; t = &(*t)->next) { | |
641 | len = strlen((*t)->name); | |
642 | if (len > max_tracer_type_len) | |
643 | max_tracer_type_len = len; | |
644 | } | |
645 | out: | |
646 | mutex_unlock(&trace_types_lock); | |
647 | } | |
648 | ||
3928a8a2 | 649 | void tracing_reset(struct trace_array *tr, int cpu) |
bc0c38d1 | 650 | { |
d769041f | 651 | ftrace_disable_cpu(); |
3928a8a2 | 652 | ring_buffer_reset_cpu(tr->buffer, cpu); |
d769041f | 653 | ftrace_enable_cpu(); |
bc0c38d1 SR |
654 | } |
655 | ||
213cc060 PE |
656 | void tracing_reset_online_cpus(struct trace_array *tr) |
657 | { | |
621968cd | 658 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
659 | int cpu; |
660 | ||
621968cd SR |
661 | ring_buffer_record_disable(buffer); |
662 | ||
663 | /* Make sure all commits have finished */ | |
664 | synchronize_sched(); | |
665 | ||
213cc060 PE |
666 | tr->time_start = ftrace_now(tr->cpu); |
667 | ||
668 | for_each_online_cpu(cpu) | |
669 | tracing_reset(tr, cpu); | |
621968cd SR |
670 | |
671 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
672 | } |
673 | ||
9456f0fa SR |
674 | void tracing_reset_current(int cpu) |
675 | { | |
676 | tracing_reset(&global_trace, cpu); | |
677 | } | |
678 | ||
679 | void tracing_reset_current_online_cpus(void) | |
680 | { | |
681 | tracing_reset_online_cpus(&global_trace); | |
682 | } | |
683 | ||
bc0c38d1 | 684 | #define SAVED_CMDLINES 128 |
2c7eea4c | 685 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
686 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
687 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
688 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
689 | static int cmdline_idx; | |
efed792d | 690 | static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; |
25b0b44a | 691 | |
25b0b44a | 692 | /* temporary disable recording */ |
4fd27358 | 693 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
694 | |
695 | static void trace_init_cmdlines(void) | |
696 | { | |
2c7eea4c TG |
697 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
698 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
699 | cmdline_idx = 0; |
700 | } | |
701 | ||
69bb54ec SR |
702 | /** |
703 | * ftrace_off_permanent - disable all ftrace code permanently | |
704 | * | |
705 | * This should only be called when a serious anomally has | |
706 | * been detected. This will turn off the function tracing, | |
707 | * ring buffers, and other tracing utilites. It takes no | |
708 | * locks and can be called from any context. | |
709 | */ | |
710 | void ftrace_off_permanent(void) | |
711 | { | |
712 | tracing_disabled = 1; | |
713 | ftrace_stop(); | |
714 | tracing_off_permanent(); | |
715 | } | |
716 | ||
0f048701 SR |
717 | /** |
718 | * tracing_start - quick start of the tracer | |
719 | * | |
720 | * If tracing is enabled but was stopped by tracing_stop, | |
721 | * this will start the tracer back up. | |
722 | */ | |
723 | void tracing_start(void) | |
724 | { | |
725 | struct ring_buffer *buffer; | |
726 | unsigned long flags; | |
727 | ||
728 | if (tracing_disabled) | |
729 | return; | |
730 | ||
731 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
732 | if (--trace_stop_count) { |
733 | if (trace_stop_count < 0) { | |
734 | /* Someone screwed up their debugging */ | |
735 | WARN_ON_ONCE(1); | |
736 | trace_stop_count = 0; | |
737 | } | |
0f048701 SR |
738 | goto out; |
739 | } | |
740 | ||
741 | ||
742 | buffer = global_trace.buffer; | |
743 | if (buffer) | |
744 | ring_buffer_record_enable(buffer); | |
745 | ||
746 | buffer = max_tr.buffer; | |
747 | if (buffer) | |
748 | ring_buffer_record_enable(buffer); | |
749 | ||
750 | ftrace_start(); | |
751 | out: | |
752 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
753 | } | |
754 | ||
755 | /** | |
756 | * tracing_stop - quick stop of the tracer | |
757 | * | |
758 | * Light weight way to stop tracing. Use in conjunction with | |
759 | * tracing_start. | |
760 | */ | |
761 | void tracing_stop(void) | |
762 | { | |
763 | struct ring_buffer *buffer; | |
764 | unsigned long flags; | |
765 | ||
766 | ftrace_stop(); | |
767 | spin_lock_irqsave(&tracing_start_lock, flags); | |
768 | if (trace_stop_count++) | |
769 | goto out; | |
770 | ||
771 | buffer = global_trace.buffer; | |
772 | if (buffer) | |
773 | ring_buffer_record_disable(buffer); | |
774 | ||
775 | buffer = max_tr.buffer; | |
776 | if (buffer) | |
777 | ring_buffer_record_disable(buffer); | |
778 | ||
779 | out: | |
780 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
781 | } | |
782 | ||
e309b41d | 783 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 784 | |
e309b41d | 785 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 786 | { |
a635cf04 | 787 | unsigned pid, idx; |
bc0c38d1 SR |
788 | |
789 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
790 | return; | |
791 | ||
792 | /* | |
793 | * It's not the end of the world if we don't get | |
794 | * the lock, but we also don't want to spin | |
795 | * nor do we want to disable interrupts, | |
796 | * so if we miss here, then better luck next time. | |
797 | */ | |
efed792d | 798 | if (!__raw_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
799 | return; |
800 | ||
801 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 802 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
803 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
804 | ||
a635cf04 CE |
805 | /* |
806 | * Check whether the cmdline buffer at idx has a pid | |
807 | * mapped. We are going to overwrite that entry so we | |
808 | * need to clear the map_pid_to_cmdline. Otherwise we | |
809 | * would read the new comm for the old pid. | |
810 | */ | |
811 | pid = map_cmdline_to_pid[idx]; | |
812 | if (pid != NO_CMDLINE_MAP) | |
813 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 814 | |
a635cf04 | 815 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
816 | map_pid_to_cmdline[tsk->pid] = idx; |
817 | ||
818 | cmdline_idx = idx; | |
819 | } | |
820 | ||
821 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
822 | ||
efed792d | 823 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
824 | } |
825 | ||
4ca53085 | 826 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 827 | { |
bc0c38d1 SR |
828 | unsigned map; |
829 | ||
4ca53085 SR |
830 | if (!pid) { |
831 | strcpy(comm, "<idle>"); | |
832 | return; | |
833 | } | |
bc0c38d1 | 834 | |
4ca53085 SR |
835 | if (pid > PID_MAX_DEFAULT) { |
836 | strcpy(comm, "<...>"); | |
837 | return; | |
838 | } | |
bc0c38d1 | 839 | |
5b6045a9 | 840 | preempt_disable(); |
4ca53085 | 841 | __raw_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 842 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
843 | if (map != NO_CMDLINE_MAP) |
844 | strcpy(comm, saved_cmdlines[map]); | |
845 | else | |
846 | strcpy(comm, "<...>"); | |
bc0c38d1 | 847 | |
4ca53085 | 848 | __raw_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 849 | preempt_enable(); |
bc0c38d1 SR |
850 | } |
851 | ||
e309b41d | 852 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 853 | { |
18aecd36 TG |
854 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
855 | !tracing_is_on()) | |
bc0c38d1 SR |
856 | return; |
857 | ||
858 | trace_save_cmdline(tsk); | |
859 | } | |
860 | ||
45dcd8b8 | 861 | void |
38697053 SR |
862 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
863 | int pc) | |
bc0c38d1 SR |
864 | { |
865 | struct task_struct *tsk = current; | |
bc0c38d1 | 866 | |
777e208d SR |
867 | entry->preempt_count = pc & 0xff; |
868 | entry->pid = (tsk) ? tsk->pid : 0; | |
ef18012b | 869 | entry->tgid = (tsk) ? tsk->tgid : 0; |
777e208d | 870 | entry->flags = |
9244489a | 871 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 872 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
873 | #else |
874 | TRACE_FLAG_IRQS_NOSUPPORT | | |
875 | #endif | |
bc0c38d1 SR |
876 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
877 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
878 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
879 | } | |
f413cdb8 | 880 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 881 | |
51a763dd | 882 | struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr, |
7a4f453b | 883 | int type, |
51a763dd ACM |
884 | unsigned long len, |
885 | unsigned long flags, int pc) | |
886 | { | |
887 | struct ring_buffer_event *event; | |
888 | ||
889 | event = ring_buffer_lock_reserve(tr->buffer, len); | |
890 | if (event != NULL) { | |
891 | struct trace_entry *ent = ring_buffer_event_data(event); | |
892 | ||
893 | tracing_generic_entry_update(ent, flags, pc); | |
894 | ent->type = type; | |
895 | } | |
896 | ||
897 | return event; | |
898 | } | |
51a763dd | 899 | |
07edf712 FW |
900 | static inline void __trace_buffer_unlock_commit(struct trace_array *tr, |
901 | struct ring_buffer_event *event, | |
902 | unsigned long flags, int pc, | |
903 | int wake) | |
51a763dd ACM |
904 | { |
905 | ring_buffer_unlock_commit(tr->buffer, event); | |
906 | ||
907 | ftrace_trace_stack(tr, flags, 6, pc); | |
908 | ftrace_trace_userstack(tr, flags, pc); | |
07edf712 FW |
909 | |
910 | if (wake) | |
911 | trace_wake_up(); | |
912 | } | |
913 | ||
914 | void trace_buffer_unlock_commit(struct trace_array *tr, | |
915 | struct ring_buffer_event *event, | |
916 | unsigned long flags, int pc) | |
917 | { | |
918 | __trace_buffer_unlock_commit(tr, event, flags, pc, 1); | |
51a763dd ACM |
919 | } |
920 | ||
ef5580d0 | 921 | struct ring_buffer_event * |
7a4f453b | 922 | trace_current_buffer_lock_reserve(int type, unsigned long len, |
ef5580d0 SR |
923 | unsigned long flags, int pc) |
924 | { | |
925 | return trace_buffer_lock_reserve(&global_trace, | |
926 | type, len, flags, pc); | |
927 | } | |
94487d6d | 928 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 SR |
929 | |
930 | void trace_current_buffer_unlock_commit(struct ring_buffer_event *event, | |
931 | unsigned long flags, int pc) | |
932 | { | |
77d9f465 | 933 | __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 1); |
07edf712 | 934 | } |
94487d6d | 935 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 FW |
936 | |
937 | void trace_nowake_buffer_unlock_commit(struct ring_buffer_event *event, | |
938 | unsigned long flags, int pc) | |
939 | { | |
77d9f465 SR |
940 | __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 0); |
941 | } | |
94487d6d | 942 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 SR |
943 | |
944 | void trace_current_buffer_discard_commit(struct ring_buffer_event *event) | |
945 | { | |
946 | ring_buffer_discard_commit(global_trace.buffer, event); | |
ef5580d0 | 947 | } |
12acd473 | 948 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 949 | |
e309b41d | 950 | void |
7be42151 | 951 | trace_function(struct trace_array *tr, |
38697053 SR |
952 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
953 | int pc) | |
bc0c38d1 | 954 | { |
e1112b4d | 955 | struct ftrace_event_call *call = &event_function; |
3928a8a2 | 956 | struct ring_buffer_event *event; |
777e208d | 957 | struct ftrace_entry *entry; |
bc0c38d1 | 958 | |
d769041f SR |
959 | /* If we are reading the ring buffer, don't trace */ |
960 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
961 | return; | |
962 | ||
51a763dd ACM |
963 | event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry), |
964 | flags, pc); | |
3928a8a2 SR |
965 | if (!event) |
966 | return; | |
967 | entry = ring_buffer_event_data(event); | |
777e208d SR |
968 | entry->ip = ip; |
969 | entry->parent_ip = parent_ip; | |
e1112b4d | 970 | |
eb02ce01 TZ |
971 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
972 | ring_buffer_unlock_commit(tr->buffer, event); | |
bc0c38d1 SR |
973 | } |
974 | ||
e309b41d | 975 | void |
2e0f5761 | 976 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
977 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
978 | int pc) | |
2e0f5761 IM |
979 | { |
980 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 981 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
982 | } |
983 | ||
c0a0d0d3 | 984 | #ifdef CONFIG_STACKTRACE |
53614991 | 985 | static void __ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
986 | unsigned long flags, |
987 | int skip, int pc) | |
86387f7e | 988 | { |
e1112b4d | 989 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 990 | struct ring_buffer_event *event; |
777e208d | 991 | struct stack_entry *entry; |
86387f7e IM |
992 | struct stack_trace trace; |
993 | ||
51a763dd ACM |
994 | event = trace_buffer_lock_reserve(tr, TRACE_STACK, |
995 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
996 | if (!event) |
997 | return; | |
998 | entry = ring_buffer_event_data(event); | |
777e208d | 999 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
1000 | |
1001 | trace.nr_entries = 0; | |
1002 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1003 | trace.skip = skip; | |
777e208d | 1004 | trace.entries = entry->caller; |
86387f7e IM |
1005 | |
1006 | save_stack_trace(&trace); | |
eb02ce01 TZ |
1007 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1008 | ring_buffer_unlock_commit(tr->buffer, event); | |
f0a920d5 IM |
1009 | } |
1010 | ||
c0a0d0d3 FW |
1011 | void ftrace_trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1012 | int pc) | |
53614991 SR |
1013 | { |
1014 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1015 | return; | |
1016 | ||
7be42151 | 1017 | __ftrace_trace_stack(tr, flags, skip, pc); |
53614991 SR |
1018 | } |
1019 | ||
c0a0d0d3 FW |
1020 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1021 | int pc) | |
38697053 | 1022 | { |
7be42151 | 1023 | __ftrace_trace_stack(tr, flags, skip, pc); |
38697053 SR |
1024 | } |
1025 | ||
c0a0d0d3 | 1026 | void ftrace_trace_userstack(struct trace_array *tr, unsigned long flags, int pc) |
02b67518 | 1027 | { |
e1112b4d | 1028 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1029 | struct ring_buffer_event *event; |
02b67518 TE |
1030 | struct userstack_entry *entry; |
1031 | struct stack_trace trace; | |
02b67518 TE |
1032 | |
1033 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1034 | return; | |
1035 | ||
51a763dd ACM |
1036 | event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK, |
1037 | sizeof(*entry), flags, pc); | |
02b67518 TE |
1038 | if (!event) |
1039 | return; | |
1040 | entry = ring_buffer_event_data(event); | |
02b67518 TE |
1041 | |
1042 | memset(&entry->caller, 0, sizeof(entry->caller)); | |
1043 | ||
1044 | trace.nr_entries = 0; | |
1045 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1046 | trace.skip = 0; | |
1047 | trace.entries = entry->caller; | |
1048 | ||
1049 | save_stack_trace_user(&trace); | |
eb02ce01 TZ |
1050 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1051 | ring_buffer_unlock_commit(tr->buffer, event); | |
02b67518 TE |
1052 | } |
1053 | ||
4fd27358 HE |
1054 | #ifdef UNUSED |
1055 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1056 | { |
7be42151 | 1057 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1058 | } |
4fd27358 | 1059 | #endif /* UNUSED */ |
02b67518 | 1060 | |
c0a0d0d3 FW |
1061 | #endif /* CONFIG_STACKTRACE */ |
1062 | ||
38697053 | 1063 | static void |
7be42151 | 1064 | ftrace_trace_special(void *__tr, |
38697053 SR |
1065 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1066 | int pc) | |
a4feb834 | 1067 | { |
3928a8a2 | 1068 | struct ring_buffer_event *event; |
a4feb834 | 1069 | struct trace_array *tr = __tr; |
777e208d | 1070 | struct special_entry *entry; |
a4feb834 | 1071 | |
51a763dd ACM |
1072 | event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL, |
1073 | sizeof(*entry), 0, pc); | |
3928a8a2 SR |
1074 | if (!event) |
1075 | return; | |
1076 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1077 | entry->arg1 = arg1; |
1078 | entry->arg2 = arg2; | |
1079 | entry->arg3 = arg3; | |
51a763dd | 1080 | trace_buffer_unlock_commit(tr, event, 0, pc); |
a4feb834 IM |
1081 | } |
1082 | ||
38697053 SR |
1083 | void |
1084 | __trace_special(void *__tr, void *__data, | |
1085 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1086 | { | |
7be42151 | 1087 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1088 | } |
1089 | ||
4902f884 SR |
1090 | void |
1091 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1092 | { | |
1093 | struct trace_array *tr = &global_trace; | |
1094 | struct trace_array_cpu *data; | |
5aa1ba6a | 1095 | unsigned long flags; |
4902f884 | 1096 | int cpu; |
38697053 | 1097 | int pc; |
4902f884 | 1098 | |
c76f0694 | 1099 | if (tracing_disabled) |
4902f884 SR |
1100 | return; |
1101 | ||
38697053 | 1102 | pc = preempt_count(); |
5aa1ba6a | 1103 | local_irq_save(flags); |
4902f884 SR |
1104 | cpu = raw_smp_processor_id(); |
1105 | data = tr->data[cpu]; | |
4902f884 | 1106 | |
5aa1ba6a | 1107 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1108 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1109 | |
5aa1ba6a SR |
1110 | atomic_dec(&data->disabled); |
1111 | local_irq_restore(flags); | |
4902f884 SR |
1112 | } |
1113 | ||
769b0441 | 1114 | /** |
48ead020 | 1115 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1116 | * |
1117 | */ | |
40ce74f1 | 1118 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1119 | { |
80370cb7 SR |
1120 | static raw_spinlock_t trace_buf_lock = |
1121 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
769b0441 FW |
1122 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1123 | ||
e1112b4d | 1124 | struct ftrace_event_call *call = &event_bprint; |
769b0441 FW |
1125 | struct ring_buffer_event *event; |
1126 | struct trace_array *tr = &global_trace; | |
1127 | struct trace_array_cpu *data; | |
48ead020 | 1128 | struct bprint_entry *entry; |
769b0441 | 1129 | unsigned long flags; |
3189cdb3 | 1130 | int disable; |
769b0441 FW |
1131 | int resched; |
1132 | int cpu, len = 0, size, pc; | |
1133 | ||
1134 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1135 | return 0; | |
1136 | ||
1137 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1138 | pause_graph_tracing(); | |
1139 | ||
1140 | pc = preempt_count(); | |
1141 | resched = ftrace_preempt_disable(); | |
1142 | cpu = raw_smp_processor_id(); | |
1143 | data = tr->data[cpu]; | |
1144 | ||
3189cdb3 SR |
1145 | disable = atomic_inc_return(&data->disabled); |
1146 | if (unlikely(disable != 1)) | |
769b0441 FW |
1147 | goto out; |
1148 | ||
80370cb7 SR |
1149 | /* Lockdep uses trace_printk for lock tracing */ |
1150 | local_irq_save(flags); | |
1151 | __raw_spin_lock(&trace_buf_lock); | |
769b0441 FW |
1152 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1153 | ||
1154 | if (len > TRACE_BUF_SIZE || len < 0) | |
1155 | goto out_unlock; | |
1156 | ||
1157 | size = sizeof(*entry) + sizeof(u32) * len; | |
48ead020 | 1158 | event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc); |
769b0441 FW |
1159 | if (!event) |
1160 | goto out_unlock; | |
1161 | entry = ring_buffer_event_data(event); | |
1162 | entry->ip = ip; | |
769b0441 FW |
1163 | entry->fmt = fmt; |
1164 | ||
1165 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
eb02ce01 TZ |
1166 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1167 | ring_buffer_unlock_commit(tr->buffer, event); | |
769b0441 FW |
1168 | |
1169 | out_unlock: | |
80370cb7 SR |
1170 | __raw_spin_unlock(&trace_buf_lock); |
1171 | local_irq_restore(flags); | |
769b0441 FW |
1172 | |
1173 | out: | |
3189cdb3 | 1174 | atomic_dec_return(&data->disabled); |
769b0441 FW |
1175 | ftrace_preempt_enable(resched); |
1176 | unpause_graph_tracing(); | |
1177 | ||
1178 | return len; | |
1179 | } | |
48ead020 FW |
1180 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1181 | ||
40ce74f1 | 1182 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
48ead020 FW |
1183 | { |
1184 | static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; | |
1185 | static char trace_buf[TRACE_BUF_SIZE]; | |
1186 | ||
e1112b4d | 1187 | struct ftrace_event_call *call = &event_print; |
48ead020 FW |
1188 | struct ring_buffer_event *event; |
1189 | struct trace_array *tr = &global_trace; | |
1190 | struct trace_array_cpu *data; | |
1191 | int cpu, len = 0, size, pc; | |
1192 | struct print_entry *entry; | |
1193 | unsigned long irq_flags; | |
3189cdb3 | 1194 | int disable; |
48ead020 FW |
1195 | |
1196 | if (tracing_disabled || tracing_selftest_running) | |
1197 | return 0; | |
1198 | ||
1199 | pc = preempt_count(); | |
1200 | preempt_disable_notrace(); | |
1201 | cpu = raw_smp_processor_id(); | |
1202 | data = tr->data[cpu]; | |
1203 | ||
3189cdb3 SR |
1204 | disable = atomic_inc_return(&data->disabled); |
1205 | if (unlikely(disable != 1)) | |
48ead020 FW |
1206 | goto out; |
1207 | ||
1208 | pause_graph_tracing(); | |
1209 | raw_local_irq_save(irq_flags); | |
1210 | __raw_spin_lock(&trace_buf_lock); | |
1211 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); | |
1212 | ||
1213 | len = min(len, TRACE_BUF_SIZE-1); | |
1214 | trace_buf[len] = 0; | |
1215 | ||
1216 | size = sizeof(*entry) + len + 1; | |
1217 | event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc); | |
1218 | if (!event) | |
1219 | goto out_unlock; | |
1220 | entry = ring_buffer_event_data(event); | |
1221 | entry->ip = ip; | |
48ead020 FW |
1222 | |
1223 | memcpy(&entry->buf, trace_buf, len); | |
1224 | entry->buf[len] = 0; | |
eb02ce01 TZ |
1225 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1226 | ring_buffer_unlock_commit(tr->buffer, event); | |
48ead020 FW |
1227 | |
1228 | out_unlock: | |
1229 | __raw_spin_unlock(&trace_buf_lock); | |
1230 | raw_local_irq_restore(irq_flags); | |
1231 | unpause_graph_tracing(); | |
1232 | out: | |
3189cdb3 | 1233 | atomic_dec_return(&data->disabled); |
48ead020 FW |
1234 | preempt_enable_notrace(); |
1235 | ||
1236 | return len; | |
1237 | } | |
769b0441 FW |
1238 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1239 | ||
bc0c38d1 SR |
1240 | enum trace_file_type { |
1241 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1242 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1243 | }; |
1244 | ||
e2ac8ef5 | 1245 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1246 | { |
d769041f SR |
1247 | /* Don't allow ftrace to trace into the ring buffers */ |
1248 | ftrace_disable_cpu(); | |
1249 | ||
5a90f577 | 1250 | iter->idx++; |
d769041f SR |
1251 | if (iter->buffer_iter[iter->cpu]) |
1252 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1253 | ||
1254 | ftrace_enable_cpu(); | |
5a90f577 SR |
1255 | } |
1256 | ||
e309b41d | 1257 | static struct trace_entry * |
3928a8a2 | 1258 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1259 | { |
3928a8a2 SR |
1260 | struct ring_buffer_event *event; |
1261 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1262 | |
d769041f SR |
1263 | /* Don't allow ftrace to trace into the ring buffers */ |
1264 | ftrace_disable_cpu(); | |
1265 | ||
1266 | if (buf_iter) | |
1267 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1268 | else | |
1269 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1270 | ||
1271 | ftrace_enable_cpu(); | |
1272 | ||
3928a8a2 | 1273 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1274 | } |
d769041f | 1275 | |
dd0e545f | 1276 | static struct trace_entry * |
3928a8a2 | 1277 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1278 | { |
3928a8a2 | 1279 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1280 | struct trace_entry *ent, *next = NULL; |
b04cc6b1 | 1281 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1282 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1283 | int next_cpu = -1; |
1284 | int cpu; | |
1285 | ||
b04cc6b1 FW |
1286 | /* |
1287 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1288 | * all cpu and peek directly. | |
1289 | */ | |
1290 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1291 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1292 | return NULL; | |
1293 | ent = peek_next_entry(iter, cpu_file, ent_ts); | |
1294 | if (ent_cpu) | |
1295 | *ent_cpu = cpu_file; | |
1296 | ||
1297 | return ent; | |
1298 | } | |
1299 | ||
ab46428c | 1300 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1301 | |
3928a8a2 SR |
1302 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1303 | continue; | |
dd0e545f | 1304 | |
3928a8a2 | 1305 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1306 | |
cdd31cd2 IM |
1307 | /* |
1308 | * Pick the entry with the smallest timestamp: | |
1309 | */ | |
3928a8a2 | 1310 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1311 | next = ent; |
1312 | next_cpu = cpu; | |
3928a8a2 | 1313 | next_ts = ts; |
bc0c38d1 SR |
1314 | } |
1315 | } | |
1316 | ||
1317 | if (ent_cpu) | |
1318 | *ent_cpu = next_cpu; | |
1319 | ||
3928a8a2 SR |
1320 | if (ent_ts) |
1321 | *ent_ts = next_ts; | |
1322 | ||
bc0c38d1 SR |
1323 | return next; |
1324 | } | |
1325 | ||
dd0e545f | 1326 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1327 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1328 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1329 | { |
3928a8a2 | 1330 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1331 | } |
1332 | ||
1333 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1334 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1335 | { | |
3928a8a2 | 1336 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1337 | |
3928a8a2 | 1338 | if (iter->ent) |
e2ac8ef5 | 1339 | trace_iterator_increment(iter); |
dd0e545f | 1340 | |
3928a8a2 | 1341 | return iter->ent ? iter : NULL; |
b3806b43 | 1342 | } |
bc0c38d1 | 1343 | |
e309b41d | 1344 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1345 | { |
d769041f SR |
1346 | /* Don't allow ftrace to trace into the ring buffers */ |
1347 | ftrace_disable_cpu(); | |
3928a8a2 | 1348 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1349 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1350 | } |
1351 | ||
e309b41d | 1352 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1353 | { |
1354 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1355 | int i = (int)*pos; |
4e3c3333 | 1356 | void *ent; |
bc0c38d1 SR |
1357 | |
1358 | (*pos)++; | |
1359 | ||
1360 | /* can't go backwards */ | |
1361 | if (iter->idx > i) | |
1362 | return NULL; | |
1363 | ||
1364 | if (iter->idx < 0) | |
1365 | ent = find_next_entry_inc(iter); | |
1366 | else | |
1367 | ent = iter; | |
1368 | ||
1369 | while (ent && iter->idx < i) | |
1370 | ent = find_next_entry_inc(iter); | |
1371 | ||
1372 | iter->pos = *pos; | |
1373 | ||
bc0c38d1 SR |
1374 | return ent; |
1375 | } | |
1376 | ||
d7350c3f FW |
1377 | /* |
1378 | * No necessary locking here. The worst thing which can | |
1379 | * happen is loosing events consumed at the same time | |
1380 | * by a trace_pipe reader. | |
1381 | * Other than that, we don't risk to crash the ring buffer | |
1382 | * because it serializes the readers. | |
1383 | * | |
1384 | * The current tracer is copied to avoid a global locking | |
1385 | * all around. | |
1386 | */ | |
bc0c38d1 SR |
1387 | static void *s_start(struct seq_file *m, loff_t *pos) |
1388 | { | |
1389 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1390 | static struct tracer *old_tracer; |
b04cc6b1 | 1391 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1392 | void *p = NULL; |
1393 | loff_t l = 0; | |
3928a8a2 | 1394 | int cpu; |
bc0c38d1 | 1395 | |
d7350c3f | 1396 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1397 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1398 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1399 | old_tracer = current_trace; | |
1400 | *iter->trace = *current_trace; | |
d15f57f2 | 1401 | } |
d7350c3f | 1402 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1403 | |
1404 | atomic_inc(&trace_record_cmdline_disabled); | |
1405 | ||
bc0c38d1 SR |
1406 | if (*pos != iter->pos) { |
1407 | iter->ent = NULL; | |
1408 | iter->cpu = 0; | |
1409 | iter->idx = -1; | |
1410 | ||
d769041f SR |
1411 | ftrace_disable_cpu(); |
1412 | ||
b04cc6b1 FW |
1413 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1414 | for_each_tracing_cpu(cpu) | |
1415 | ring_buffer_iter_reset(iter->buffer_iter[cpu]); | |
1416 | } else | |
1417 | ring_buffer_iter_reset(iter->buffer_iter[cpu_file]); | |
1418 | ||
bc0c38d1 | 1419 | |
d769041f SR |
1420 | ftrace_enable_cpu(); |
1421 | ||
bc0c38d1 SR |
1422 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1423 | ; | |
1424 | ||
1425 | } else { | |
4c11d7ae | 1426 | l = *pos - 1; |
bc0c38d1 SR |
1427 | p = s_next(m, p, &l); |
1428 | } | |
1429 | ||
4f535968 | 1430 | trace_event_read_lock(); |
bc0c38d1 SR |
1431 | return p; |
1432 | } | |
1433 | ||
1434 | static void s_stop(struct seq_file *m, void *p) | |
1435 | { | |
bc0c38d1 | 1436 | atomic_dec(&trace_record_cmdline_disabled); |
4f535968 | 1437 | trace_event_read_unlock(); |
bc0c38d1 SR |
1438 | } |
1439 | ||
e309b41d | 1440 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1441 | { |
a6168353 ME |
1442 | seq_puts(m, "# _------=> CPU# \n"); |
1443 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1444 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1445 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1446 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1447 | seq_puts(m, "# |||| / \n"); | |
1448 | seq_puts(m, "# ||||| delay \n"); | |
1449 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1450 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1451 | } |
1452 | ||
e309b41d | 1453 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1454 | { |
a6168353 ME |
1455 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1456 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1457 | } |
1458 | ||
1459 | ||
e309b41d | 1460 | static void |
bc0c38d1 SR |
1461 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1462 | { | |
1463 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1464 | struct trace_array *tr = iter->tr; | |
1465 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1466 | struct tracer *type = current_trace; | |
3928a8a2 SR |
1467 | unsigned long total; |
1468 | unsigned long entries; | |
bc0c38d1 SR |
1469 | const char *name = "preemption"; |
1470 | ||
1471 | if (type) | |
1472 | name = type->name; | |
1473 | ||
3928a8a2 SR |
1474 | entries = ring_buffer_entries(iter->tr->buffer); |
1475 | total = entries + | |
1476 | ring_buffer_overruns(iter->tr->buffer); | |
bc0c38d1 | 1477 | |
888b55dc | 1478 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1479 | name, UTS_RELEASE); |
888b55dc | 1480 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1481 | "---------------------------------\n"); |
888b55dc | 1482 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1483 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1484 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1485 | entries, |
4c11d7ae | 1486 | total, |
bc0c38d1 SR |
1487 | tr->cpu, |
1488 | #if defined(CONFIG_PREEMPT_NONE) | |
1489 | "server", | |
1490 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1491 | "desktop", | |
b5c21b45 | 1492 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1493 | "preempt", |
1494 | #else | |
1495 | "unknown", | |
1496 | #endif | |
1497 | /* These are reserved for later use */ | |
1498 | 0, 0, 0, 0); | |
1499 | #ifdef CONFIG_SMP | |
1500 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1501 | #else | |
1502 | seq_puts(m, ")\n"); | |
1503 | #endif | |
888b55dc KM |
1504 | seq_puts(m, "# -----------------\n"); |
1505 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1506 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1507 | data->comm, data->pid, data->uid, data->nice, | |
1508 | data->policy, data->rt_priority); | |
888b55dc | 1509 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1510 | |
1511 | if (data->critical_start) { | |
888b55dc | 1512 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1513 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1514 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1515 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1516 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1517 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 1518 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
1519 | } |
1520 | ||
888b55dc | 1521 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1522 | } |
1523 | ||
a309720c SR |
1524 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1525 | { | |
1526 | struct trace_seq *s = &iter->seq; | |
1527 | ||
12ef7d44 SR |
1528 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1529 | return; | |
1530 | ||
1531 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1532 | return; | |
1533 | ||
4462344e | 1534 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1535 | return; |
1536 | ||
4462344e | 1537 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1538 | |
1539 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1540 | if (iter->idx > 1) | |
1541 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1542 | iter->cpu); | |
a309720c SR |
1543 | } |
1544 | ||
2c4f035f | 1545 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1546 | { |
214023c3 | 1547 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1548 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1549 | struct trace_entry *entry; |
f633cef0 | 1550 | struct trace_event *event; |
bc0c38d1 | 1551 | |
4e3c3333 | 1552 | entry = iter->ent; |
dd0e545f | 1553 | |
a309720c SR |
1554 | test_cpu_buff_start(iter); |
1555 | ||
c4a8e8be | 1556 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1557 | |
c4a8e8be | 1558 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1559 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1560 | if (!trace_print_lat_context(iter)) | |
1561 | goto partial; | |
1562 | } else { | |
1563 | if (!trace_print_context(iter)) | |
1564 | goto partial; | |
1565 | } | |
c4a8e8be | 1566 | } |
bc0c38d1 | 1567 | |
268ccda0 | 1568 | if (event) |
d9793bd8 ACM |
1569 | return event->trace(iter, sym_flags); |
1570 | ||
1571 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1572 | goto partial; | |
02b67518 | 1573 | |
2c4f035f | 1574 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1575 | partial: |
1576 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1577 | } |
1578 | ||
2c4f035f | 1579 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1580 | { |
1581 | struct trace_seq *s = &iter->seq; | |
1582 | struct trace_entry *entry; | |
f633cef0 | 1583 | struct trace_event *event; |
f9896bf3 IM |
1584 | |
1585 | entry = iter->ent; | |
dd0e545f | 1586 | |
c4a8e8be | 1587 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1588 | if (!trace_seq_printf(s, "%d %d %llu ", |
1589 | entry->pid, iter->cpu, iter->ts)) | |
1590 | goto partial; | |
c4a8e8be | 1591 | } |
f9896bf3 | 1592 | |
f633cef0 | 1593 | event = ftrace_find_event(entry->type); |
268ccda0 | 1594 | if (event) |
d9793bd8 ACM |
1595 | return event->raw(iter, 0); |
1596 | ||
1597 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1598 | goto partial; | |
777e208d | 1599 | |
2c4f035f | 1600 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1601 | partial: |
1602 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1603 | } |
1604 | ||
2c4f035f | 1605 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1606 | { |
1607 | struct trace_seq *s = &iter->seq; | |
1608 | unsigned char newline = '\n'; | |
1609 | struct trace_entry *entry; | |
f633cef0 | 1610 | struct trace_event *event; |
5e3ca0ec IM |
1611 | |
1612 | entry = iter->ent; | |
dd0e545f | 1613 | |
c4a8e8be FW |
1614 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1615 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1616 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1617 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1618 | } | |
5e3ca0ec | 1619 | |
f633cef0 | 1620 | event = ftrace_find_event(entry->type); |
268ccda0 | 1621 | if (event) { |
ae7462b4 | 1622 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1623 | if (ret != TRACE_TYPE_HANDLED) |
1624 | return ret; | |
1625 | } | |
7104f300 | 1626 | |
5e3ca0ec IM |
1627 | SEQ_PUT_FIELD_RET(s, newline); |
1628 | ||
2c4f035f | 1629 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1630 | } |
1631 | ||
2c4f035f | 1632 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1633 | { |
1634 | struct trace_seq *s = &iter->seq; | |
1635 | struct trace_entry *entry; | |
f633cef0 | 1636 | struct trace_event *event; |
cb0f12aa IM |
1637 | |
1638 | entry = iter->ent; | |
dd0e545f | 1639 | |
c4a8e8be FW |
1640 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1641 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1642 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1643 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1644 | } | |
cb0f12aa | 1645 | |
f633cef0 | 1646 | event = ftrace_find_event(entry->type); |
268ccda0 | 1647 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1648 | } |
1649 | ||
bc0c38d1 SR |
1650 | static int trace_empty(struct trace_iterator *iter) |
1651 | { | |
bc0c38d1 SR |
1652 | int cpu; |
1653 | ||
9aba60fe SR |
1654 | /* If we are looking at one CPU buffer, only check that one */ |
1655 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1656 | cpu = iter->cpu_file; | |
1657 | if (iter->buffer_iter[cpu]) { | |
1658 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1659 | return 0; | |
1660 | } else { | |
1661 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1662 | return 0; | |
1663 | } | |
1664 | return 1; | |
1665 | } | |
1666 | ||
ab46428c | 1667 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1668 | if (iter->buffer_iter[cpu]) { |
1669 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1670 | return 0; | |
1671 | } else { | |
1672 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1673 | return 0; | |
1674 | } | |
bc0c38d1 | 1675 | } |
d769041f | 1676 | |
797d3712 | 1677 | return 1; |
bc0c38d1 SR |
1678 | } |
1679 | ||
4f535968 | 1680 | /* Called with trace_event_read_lock() held. */ |
2c4f035f | 1681 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1682 | { |
2c4f035f FW |
1683 | enum print_line_t ret; |
1684 | ||
1685 | if (iter->trace && iter->trace->print_line) { | |
1686 | ret = iter->trace->print_line(iter); | |
1687 | if (ret != TRACE_TYPE_UNHANDLED) | |
1688 | return ret; | |
1689 | } | |
72829bc3 | 1690 | |
48ead020 FW |
1691 | if (iter->ent->type == TRACE_BPRINT && |
1692 | trace_flags & TRACE_ITER_PRINTK && | |
1693 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1694 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 1695 | |
66896a85 FW |
1696 | if (iter->ent->type == TRACE_PRINT && |
1697 | trace_flags & TRACE_ITER_PRINTK && | |
1698 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1699 | return trace_print_printk_msg_only(iter); |
66896a85 | 1700 | |
cb0f12aa IM |
1701 | if (trace_flags & TRACE_ITER_BIN) |
1702 | return print_bin_fmt(iter); | |
1703 | ||
5e3ca0ec IM |
1704 | if (trace_flags & TRACE_ITER_HEX) |
1705 | return print_hex_fmt(iter); | |
1706 | ||
f9896bf3 IM |
1707 | if (trace_flags & TRACE_ITER_RAW) |
1708 | return print_raw_fmt(iter); | |
1709 | ||
f9896bf3 IM |
1710 | return print_trace_fmt(iter); |
1711 | } | |
1712 | ||
bc0c38d1 SR |
1713 | static int s_show(struct seq_file *m, void *v) |
1714 | { | |
1715 | struct trace_iterator *iter = v; | |
1716 | ||
1717 | if (iter->ent == NULL) { | |
1718 | if (iter->tr) { | |
1719 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1720 | seq_puts(m, "#\n"); | |
1721 | } | |
8bba1bf5 MM |
1722 | if (iter->trace && iter->trace->print_header) |
1723 | iter->trace->print_header(m); | |
1724 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
1725 | /* print nothing if the buffers are empty */ |
1726 | if (trace_empty(iter)) | |
1727 | return 0; | |
1728 | print_trace_header(m, iter); | |
1729 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1730 | print_lat_help_header(m); | |
1731 | } else { | |
1732 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1733 | print_func_help_header(m); | |
1734 | } | |
1735 | } else { | |
f9896bf3 | 1736 | print_trace_line(iter); |
214023c3 | 1737 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1738 | } |
1739 | ||
1740 | return 0; | |
1741 | } | |
1742 | ||
1743 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1744 | .start = s_start, |
1745 | .next = s_next, | |
1746 | .stop = s_stop, | |
1747 | .show = s_show, | |
bc0c38d1 SR |
1748 | }; |
1749 | ||
e309b41d | 1750 | static struct trace_iterator * |
85a2f9b4 | 1751 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 1752 | { |
b04cc6b1 | 1753 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 1754 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 1755 | struct trace_iterator *iter; |
3928a8a2 | 1756 | struct seq_file *m; |
85a2f9b4 | 1757 | int cpu, ret; |
bc0c38d1 | 1758 | |
85a2f9b4 SR |
1759 | if (tracing_disabled) |
1760 | return ERR_PTR(-ENODEV); | |
60a11774 | 1761 | |
bc0c38d1 | 1762 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
1763 | if (!iter) |
1764 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 1765 | |
d7350c3f FW |
1766 | /* |
1767 | * We make a copy of the current tracer to avoid concurrent | |
1768 | * changes on it while we are reading. | |
1769 | */ | |
bc0c38d1 | 1770 | mutex_lock(&trace_types_lock); |
d7350c3f | 1771 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 1772 | if (!iter->trace) |
d7350c3f | 1773 | goto fail; |
85a2f9b4 | 1774 | |
d7350c3f FW |
1775 | if (current_trace) |
1776 | *iter->trace = *current_trace; | |
1777 | ||
b0dfa978 FW |
1778 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) |
1779 | goto fail; | |
1780 | ||
1781 | cpumask_clear(iter->started); | |
1782 | ||
bc0c38d1 SR |
1783 | if (current_trace && current_trace->print_max) |
1784 | iter->tr = &max_tr; | |
1785 | else | |
b04cc6b1 | 1786 | iter->tr = &global_trace; |
bc0c38d1 | 1787 | iter->pos = -1; |
d7350c3f | 1788 | mutex_init(&iter->mutex); |
b04cc6b1 | 1789 | iter->cpu_file = cpu_file; |
bc0c38d1 | 1790 | |
8bba1bf5 MM |
1791 | /* Notify the tracer early; before we stop tracing. */ |
1792 | if (iter->trace && iter->trace->open) | |
a93751ca | 1793 | iter->trace->open(iter); |
8bba1bf5 | 1794 | |
12ef7d44 SR |
1795 | /* Annotate start of buffers if we had overruns */ |
1796 | if (ring_buffer_overruns(iter->tr->buffer)) | |
1797 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
1798 | ||
b04cc6b1 FW |
1799 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
1800 | for_each_tracing_cpu(cpu) { | |
12ef7d44 | 1801 | |
b04cc6b1 FW |
1802 | iter->buffer_iter[cpu] = |
1803 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
b04cc6b1 FW |
1804 | } |
1805 | } else { | |
1806 | cpu = iter->cpu_file; | |
3928a8a2 | 1807 | iter->buffer_iter[cpu] = |
b04cc6b1 | 1808 | ring_buffer_read_start(iter->tr->buffer, cpu); |
3928a8a2 SR |
1809 | } |
1810 | ||
bc0c38d1 | 1811 | /* TODO stop tracer */ |
85a2f9b4 SR |
1812 | ret = seq_open(file, &tracer_seq_ops); |
1813 | if (ret < 0) { | |
1814 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 1815 | goto fail_buffer; |
85a2f9b4 | 1816 | } |
bc0c38d1 | 1817 | |
3928a8a2 SR |
1818 | m = file->private_data; |
1819 | m->private = iter; | |
bc0c38d1 | 1820 | |
3928a8a2 | 1821 | /* stop the trace while dumping */ |
9036990d | 1822 | tracing_stop(); |
3928a8a2 | 1823 | |
bc0c38d1 SR |
1824 | mutex_unlock(&trace_types_lock); |
1825 | ||
bc0c38d1 | 1826 | return iter; |
3928a8a2 SR |
1827 | |
1828 | fail_buffer: | |
1829 | for_each_tracing_cpu(cpu) { | |
1830 | if (iter->buffer_iter[cpu]) | |
1831 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1832 | } | |
b0dfa978 | 1833 | free_cpumask_var(iter->started); |
d7350c3f | 1834 | fail: |
3928a8a2 | 1835 | mutex_unlock(&trace_types_lock); |
d7350c3f | 1836 | kfree(iter->trace); |
0bb943c7 | 1837 | kfree(iter); |
3928a8a2 | 1838 | |
85a2f9b4 | 1839 | return fail_ret; |
bc0c38d1 SR |
1840 | } |
1841 | ||
1842 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1843 | { | |
60a11774 SR |
1844 | if (tracing_disabled) |
1845 | return -ENODEV; | |
1846 | ||
bc0c38d1 SR |
1847 | filp->private_data = inode->i_private; |
1848 | return 0; | |
1849 | } | |
1850 | ||
4fd27358 | 1851 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
1852 | { |
1853 | struct seq_file *m = (struct seq_file *)file->private_data; | |
4acd4d00 | 1854 | struct trace_iterator *iter; |
3928a8a2 | 1855 | int cpu; |
bc0c38d1 | 1856 | |
4acd4d00 SR |
1857 | if (!(file->f_mode & FMODE_READ)) |
1858 | return 0; | |
1859 | ||
1860 | iter = m->private; | |
1861 | ||
bc0c38d1 | 1862 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
1863 | for_each_tracing_cpu(cpu) { |
1864 | if (iter->buffer_iter[cpu]) | |
1865 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1866 | } | |
1867 | ||
bc0c38d1 SR |
1868 | if (iter->trace && iter->trace->close) |
1869 | iter->trace->close(iter); | |
1870 | ||
1871 | /* reenable tracing if it was previously enabled */ | |
9036990d | 1872 | tracing_start(); |
bc0c38d1 SR |
1873 | mutex_unlock(&trace_types_lock); |
1874 | ||
1875 | seq_release(inode, file); | |
d7350c3f | 1876 | mutex_destroy(&iter->mutex); |
b0dfa978 | 1877 | free_cpumask_var(iter->started); |
d7350c3f | 1878 | kfree(iter->trace); |
bc0c38d1 SR |
1879 | kfree(iter); |
1880 | return 0; | |
1881 | } | |
1882 | ||
1883 | static int tracing_open(struct inode *inode, struct file *file) | |
1884 | { | |
85a2f9b4 SR |
1885 | struct trace_iterator *iter; |
1886 | int ret = 0; | |
bc0c38d1 | 1887 | |
4acd4d00 SR |
1888 | /* If this file was open for write, then erase contents */ |
1889 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 1890 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 1891 | long cpu = (long) inode->i_private; |
bc0c38d1 | 1892 | |
4acd4d00 SR |
1893 | if (cpu == TRACE_PIPE_ALL_CPU) |
1894 | tracing_reset_online_cpus(&global_trace); | |
1895 | else | |
1896 | tracing_reset(&global_trace, cpu); | |
1897 | } | |
bc0c38d1 | 1898 | |
4acd4d00 SR |
1899 | if (file->f_mode & FMODE_READ) { |
1900 | iter = __tracing_open(inode, file); | |
1901 | if (IS_ERR(iter)) | |
1902 | ret = PTR_ERR(iter); | |
1903 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
1904 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
1905 | } | |
bc0c38d1 SR |
1906 | return ret; |
1907 | } | |
1908 | ||
e309b41d | 1909 | static void * |
bc0c38d1 SR |
1910 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1911 | { | |
f129e965 | 1912 | struct tracer *t = v; |
bc0c38d1 SR |
1913 | |
1914 | (*pos)++; | |
1915 | ||
1916 | if (t) | |
1917 | t = t->next; | |
1918 | ||
bc0c38d1 SR |
1919 | return t; |
1920 | } | |
1921 | ||
1922 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1923 | { | |
f129e965 | 1924 | struct tracer *t; |
bc0c38d1 SR |
1925 | loff_t l = 0; |
1926 | ||
1927 | mutex_lock(&trace_types_lock); | |
f129e965 | 1928 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
1929 | ; |
1930 | ||
1931 | return t; | |
1932 | } | |
1933 | ||
1934 | static void t_stop(struct seq_file *m, void *p) | |
1935 | { | |
1936 | mutex_unlock(&trace_types_lock); | |
1937 | } | |
1938 | ||
1939 | static int t_show(struct seq_file *m, void *v) | |
1940 | { | |
1941 | struct tracer *t = v; | |
1942 | ||
1943 | if (!t) | |
1944 | return 0; | |
1945 | ||
1946 | seq_printf(m, "%s", t->name); | |
1947 | if (t->next) | |
1948 | seq_putc(m, ' '); | |
1949 | else | |
1950 | seq_putc(m, '\n'); | |
1951 | ||
1952 | return 0; | |
1953 | } | |
1954 | ||
1955 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
1956 | .start = t_start, |
1957 | .next = t_next, | |
1958 | .stop = t_stop, | |
1959 | .show = t_show, | |
bc0c38d1 SR |
1960 | }; |
1961 | ||
1962 | static int show_traces_open(struct inode *inode, struct file *file) | |
1963 | { | |
60a11774 SR |
1964 | if (tracing_disabled) |
1965 | return -ENODEV; | |
1966 | ||
f129e965 | 1967 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
1968 | } |
1969 | ||
4acd4d00 SR |
1970 | static ssize_t |
1971 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
1972 | size_t count, loff_t *ppos) | |
1973 | { | |
1974 | return count; | |
1975 | } | |
1976 | ||
5e2336a0 | 1977 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
1978 | .open = tracing_open, |
1979 | .read = seq_read, | |
4acd4d00 | 1980 | .write = tracing_write_stub, |
4bf39a94 IM |
1981 | .llseek = seq_lseek, |
1982 | .release = tracing_release, | |
bc0c38d1 SR |
1983 | }; |
1984 | ||
5e2336a0 | 1985 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
1986 | .open = show_traces_open, |
1987 | .read = seq_read, | |
1988 | .release = seq_release, | |
1989 | }; | |
1990 | ||
36dfe925 IM |
1991 | /* |
1992 | * Only trace on a CPU if the bitmask is set: | |
1993 | */ | |
9e01c1b7 | 1994 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
1995 | |
1996 | /* | |
1997 | * The tracer itself will not take this lock, but still we want | |
1998 | * to provide a consistent cpumask to user-space: | |
1999 | */ | |
2000 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2001 | ||
2002 | /* | |
2003 | * Temporary storage for the character representation of the | |
2004 | * CPU bitmask (and one more byte for the newline): | |
2005 | */ | |
2006 | static char mask_str[NR_CPUS + 1]; | |
2007 | ||
c7078de1 IM |
2008 | static ssize_t |
2009 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2010 | size_t count, loff_t *ppos) | |
2011 | { | |
36dfe925 | 2012 | int len; |
c7078de1 IM |
2013 | |
2014 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2015 | |
9e01c1b7 | 2016 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2017 | if (count - len < 2) { |
2018 | count = -EINVAL; | |
2019 | goto out_err; | |
2020 | } | |
2021 | len += sprintf(mask_str + len, "\n"); | |
2022 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2023 | ||
2024 | out_err: | |
c7078de1 IM |
2025 | mutex_unlock(&tracing_cpumask_update_lock); |
2026 | ||
2027 | return count; | |
2028 | } | |
2029 | ||
2030 | static ssize_t | |
2031 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2032 | size_t count, loff_t *ppos) | |
2033 | { | |
36dfe925 | 2034 | int err, cpu; |
9e01c1b7 RR |
2035 | cpumask_var_t tracing_cpumask_new; |
2036 | ||
2037 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2038 | return -ENOMEM; | |
c7078de1 | 2039 | |
9e01c1b7 | 2040 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2041 | if (err) |
36dfe925 IM |
2042 | goto err_unlock; |
2043 | ||
215368e8 LZ |
2044 | mutex_lock(&tracing_cpumask_update_lock); |
2045 | ||
a5e25883 | 2046 | local_irq_disable(); |
92205c23 | 2047 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 2048 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2049 | /* |
2050 | * Increase/decrease the disabled counter if we are | |
2051 | * about to flip a bit in the cpumask: | |
2052 | */ | |
9e01c1b7 RR |
2053 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2054 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2055 | atomic_inc(&global_trace.data[cpu]->disabled); |
2056 | } | |
9e01c1b7 RR |
2057 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2058 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2059 | atomic_dec(&global_trace.data[cpu]->disabled); |
2060 | } | |
2061 | } | |
92205c23 | 2062 | __raw_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2063 | local_irq_enable(); |
36dfe925 | 2064 | |
9e01c1b7 | 2065 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2066 | |
2067 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2068 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2069 | |
2070 | return count; | |
36dfe925 IM |
2071 | |
2072 | err_unlock: | |
215368e8 | 2073 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2074 | |
2075 | return err; | |
c7078de1 IM |
2076 | } |
2077 | ||
5e2336a0 | 2078 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2079 | .open = tracing_open_generic, |
2080 | .read = tracing_cpumask_read, | |
2081 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2082 | }; |
2083 | ||
2084 | static ssize_t | |
ee6bce52 | 2085 | tracing_trace_options_read(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
2086 | size_t cnt, loff_t *ppos) |
2087 | { | |
d8e83d26 SR |
2088 | struct tracer_opt *trace_opts; |
2089 | u32 tracer_flags; | |
2090 | int len = 0; | |
bc0c38d1 SR |
2091 | char *buf; |
2092 | int r = 0; | |
d8e83d26 | 2093 | int i; |
adf9f195 | 2094 | |
bc0c38d1 | 2095 | |
c3706f00 | 2096 | /* calculate max size */ |
bc0c38d1 SR |
2097 | for (i = 0; trace_options[i]; i++) { |
2098 | len += strlen(trace_options[i]); | |
5c6a3ae1 | 2099 | len += 3; /* "no" and newline */ |
bc0c38d1 SR |
2100 | } |
2101 | ||
d8e83d26 SR |
2102 | mutex_lock(&trace_types_lock); |
2103 | tracer_flags = current_trace->flags->val; | |
2104 | trace_opts = current_trace->flags->opts; | |
2105 | ||
adf9f195 FW |
2106 | /* |
2107 | * Increase the size with names of options specific | |
2108 | * of the current tracer. | |
2109 | */ | |
2110 | for (i = 0; trace_opts[i].name; i++) { | |
2111 | len += strlen(trace_opts[i].name); | |
5c6a3ae1 | 2112 | len += 3; /* "no" and newline */ |
adf9f195 FW |
2113 | } |
2114 | ||
ff4e9da2 XG |
2115 | /* +1 for \0 */ |
2116 | buf = kmalloc(len + 1, GFP_KERNEL); | |
d8e83d26 SR |
2117 | if (!buf) { |
2118 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 2119 | return -ENOMEM; |
d8e83d26 | 2120 | } |
bc0c38d1 SR |
2121 | |
2122 | for (i = 0; trace_options[i]; i++) { | |
2123 | if (trace_flags & (1 << i)) | |
5c6a3ae1 | 2124 | r += sprintf(buf + r, "%s\n", trace_options[i]); |
bc0c38d1 | 2125 | else |
5c6a3ae1 | 2126 | r += sprintf(buf + r, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2127 | } |
2128 | ||
adf9f195 FW |
2129 | for (i = 0; trace_opts[i].name; i++) { |
2130 | if (tracer_flags & trace_opts[i].bit) | |
5c6a3ae1 | 2131 | r += sprintf(buf + r, "%s\n", |
adf9f195 FW |
2132 | trace_opts[i].name); |
2133 | else | |
5c6a3ae1 | 2134 | r += sprintf(buf + r, "no%s\n", |
adf9f195 FW |
2135 | trace_opts[i].name); |
2136 | } | |
d8e83d26 | 2137 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2138 | |
ff4e9da2 | 2139 | WARN_ON(r >= len + 1); |
bc0c38d1 | 2140 | |
36dfe925 | 2141 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2142 | |
2143 | kfree(buf); | |
bc0c38d1 SR |
2144 | return r; |
2145 | } | |
2146 | ||
adf9f195 FW |
2147 | /* Try to assign a tracer specific option */ |
2148 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2149 | { | |
7770841e | 2150 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 FW |
2151 | struct tracer_opt *opts = NULL; |
2152 | int ret = 0, i = 0; | |
2153 | int len; | |
2154 | ||
7770841e Z |
2155 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2156 | opts = &tracer_flags->opts[i]; | |
adf9f195 FW |
2157 | len = strlen(opts->name); |
2158 | ||
2159 | if (strncmp(cmp, opts->name, len) == 0) { | |
7770841e | 2160 | ret = trace->set_flag(tracer_flags->val, |
adf9f195 FW |
2161 | opts->bit, !neg); |
2162 | break; | |
2163 | } | |
2164 | } | |
2165 | /* Not found */ | |
7770841e | 2166 | if (!tracer_flags->opts[i].name) |
adf9f195 FW |
2167 | return -EINVAL; |
2168 | ||
2169 | /* Refused to handle */ | |
2170 | if (ret) | |
2171 | return ret; | |
2172 | ||
2173 | if (neg) | |
7770841e | 2174 | tracer_flags->val &= ~opts->bit; |
adf9f195 | 2175 | else |
7770841e | 2176 | tracer_flags->val |= opts->bit; |
adf9f195 FW |
2177 | |
2178 | return 0; | |
2179 | } | |
2180 | ||
af4617bd SR |
2181 | static void set_tracer_flags(unsigned int mask, int enabled) |
2182 | { | |
2183 | /* do nothing if flag is already set */ | |
2184 | if (!!(trace_flags & mask) == !!enabled) | |
2185 | return; | |
2186 | ||
2187 | if (enabled) | |
2188 | trace_flags |= mask; | |
2189 | else | |
2190 | trace_flags &= ~mask; | |
af4617bd SR |
2191 | } |
2192 | ||
bc0c38d1 | 2193 | static ssize_t |
ee6bce52 | 2194 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2195 | size_t cnt, loff_t *ppos) |
2196 | { | |
2197 | char buf[64]; | |
2198 | char *cmp = buf; | |
2199 | int neg = 0; | |
adf9f195 | 2200 | int ret; |
bc0c38d1 SR |
2201 | int i; |
2202 | ||
cffae437 SR |
2203 | if (cnt >= sizeof(buf)) |
2204 | return -EINVAL; | |
bc0c38d1 SR |
2205 | |
2206 | if (copy_from_user(&buf, ubuf, cnt)) | |
2207 | return -EFAULT; | |
2208 | ||
2209 | buf[cnt] = 0; | |
2210 | ||
2211 | if (strncmp(buf, "no", 2) == 0) { | |
2212 | neg = 1; | |
2213 | cmp += 2; | |
2214 | } | |
2215 | ||
2216 | for (i = 0; trace_options[i]; i++) { | |
2217 | int len = strlen(trace_options[i]); | |
2218 | ||
2219 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
af4617bd | 2220 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2221 | break; |
2222 | } | |
2223 | } | |
adf9f195 FW |
2224 | |
2225 | /* If no option could be set, test the specific tracer options */ | |
2226 | if (!trace_options[i]) { | |
d8e83d26 | 2227 | mutex_lock(&trace_types_lock); |
adf9f195 | 2228 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2229 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2230 | if (ret) |
2231 | return ret; | |
2232 | } | |
bc0c38d1 SR |
2233 | |
2234 | filp->f_pos += cnt; | |
2235 | ||
2236 | return cnt; | |
2237 | } | |
2238 | ||
5e2336a0 | 2239 | static const struct file_operations tracing_iter_fops = { |
c7078de1 | 2240 | .open = tracing_open_generic, |
ee6bce52 SR |
2241 | .read = tracing_trace_options_read, |
2242 | .write = tracing_trace_options_write, | |
bc0c38d1 SR |
2243 | }; |
2244 | ||
7bd2f24c IM |
2245 | static const char readme_msg[] = |
2246 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2247 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2248 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
bc2b6871 | 2249 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
156f5a78 | 2250 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2251 | "nop\n" |
156f5a78 GL |
2252 | "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" |
2253 | "# cat /sys/kernel/debug/tracing/current_tracer\n" | |
7bd2f24c | 2254 | "sched_switch\n" |
156f5a78 | 2255 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2256 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 GL |
2257 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
2258 | "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
2259 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" | |
2260 | "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
7bd2f24c IM |
2261 | ; |
2262 | ||
2263 | static ssize_t | |
2264 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2265 | size_t cnt, loff_t *ppos) | |
2266 | { | |
2267 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2268 | readme_msg, strlen(readme_msg)); | |
2269 | } | |
2270 | ||
5e2336a0 | 2271 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2272 | .open = tracing_open_generic, |
2273 | .read = tracing_readme_read, | |
7bd2f24c IM |
2274 | }; |
2275 | ||
69abe6a5 AP |
2276 | static ssize_t |
2277 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2278 | size_t cnt, loff_t *ppos) | |
2279 | { | |
2280 | char *buf_comm; | |
2281 | char *file_buf; | |
2282 | char *buf; | |
2283 | int len = 0; | |
2284 | int pid; | |
2285 | int i; | |
2286 | ||
2287 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2288 | if (!file_buf) | |
2289 | return -ENOMEM; | |
2290 | ||
2291 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2292 | if (!buf_comm) { | |
2293 | kfree(file_buf); | |
2294 | return -ENOMEM; | |
2295 | } | |
2296 | ||
2297 | buf = file_buf; | |
2298 | ||
2299 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2300 | int r; | |
2301 | ||
2302 | pid = map_cmdline_to_pid[i]; | |
2303 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2304 | continue; | |
2305 | ||
2306 | trace_find_cmdline(pid, buf_comm); | |
2307 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2308 | buf += r; | |
2309 | len += r; | |
2310 | } | |
2311 | ||
2312 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2313 | file_buf, len); | |
2314 | ||
2315 | kfree(file_buf); | |
2316 | kfree(buf_comm); | |
2317 | ||
2318 | return len; | |
2319 | } | |
2320 | ||
2321 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2322 | .open = tracing_open_generic, | |
2323 | .read = tracing_saved_cmdlines_read, | |
2324 | }; | |
2325 | ||
bc0c38d1 SR |
2326 | static ssize_t |
2327 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2328 | size_t cnt, loff_t *ppos) | |
2329 | { | |
bc0c38d1 SR |
2330 | char buf[64]; |
2331 | int r; | |
2332 | ||
9036990d | 2333 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2334 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2335 | } |
2336 | ||
2337 | static ssize_t | |
2338 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2339 | size_t cnt, loff_t *ppos) | |
2340 | { | |
2341 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2342 | char buf[64]; |
5e39841c | 2343 | unsigned long val; |
c6caeeb1 | 2344 | int ret; |
bc0c38d1 | 2345 | |
cffae437 SR |
2346 | if (cnt >= sizeof(buf)) |
2347 | return -EINVAL; | |
bc0c38d1 SR |
2348 | |
2349 | if (copy_from_user(&buf, ubuf, cnt)) | |
2350 | return -EFAULT; | |
2351 | ||
2352 | buf[cnt] = 0; | |
2353 | ||
c6caeeb1 SR |
2354 | ret = strict_strtoul(buf, 10, &val); |
2355 | if (ret < 0) | |
2356 | return ret; | |
bc0c38d1 SR |
2357 | |
2358 | val = !!val; | |
2359 | ||
2360 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2361 | if (tracer_enabled ^ val) { |
2362 | if (val) { | |
bc0c38d1 | 2363 | tracer_enabled = 1; |
9036990d SR |
2364 | if (current_trace->start) |
2365 | current_trace->start(tr); | |
2366 | tracing_start(); | |
2367 | } else { | |
bc0c38d1 | 2368 | tracer_enabled = 0; |
9036990d SR |
2369 | tracing_stop(); |
2370 | if (current_trace->stop) | |
2371 | current_trace->stop(tr); | |
2372 | } | |
bc0c38d1 SR |
2373 | } |
2374 | mutex_unlock(&trace_types_lock); | |
2375 | ||
2376 | filp->f_pos += cnt; | |
2377 | ||
2378 | return cnt; | |
2379 | } | |
2380 | ||
2381 | static ssize_t | |
2382 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2383 | size_t cnt, loff_t *ppos) | |
2384 | { | |
2385 | char buf[max_tracer_type_len+2]; | |
2386 | int r; | |
2387 | ||
2388 | mutex_lock(&trace_types_lock); | |
2389 | if (current_trace) | |
2390 | r = sprintf(buf, "%s\n", current_trace->name); | |
2391 | else | |
2392 | r = sprintf(buf, "\n"); | |
2393 | mutex_unlock(&trace_types_lock); | |
2394 | ||
4bf39a94 | 2395 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2396 | } |
2397 | ||
b6f11df2 ACM |
2398 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2399 | { | |
2400 | tracing_reset_online_cpus(tr); | |
2401 | return t->init(tr); | |
2402 | } | |
2403 | ||
73c5162a SR |
2404 | static int tracing_resize_ring_buffer(unsigned long size) |
2405 | { | |
2406 | int ret; | |
2407 | ||
2408 | /* | |
2409 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2410 | * we use the size that was given, and we can forget about |
2411 | * expanding it later. | |
73c5162a SR |
2412 | */ |
2413 | ring_buffer_expanded = 1; | |
2414 | ||
2415 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2416 | if (ret < 0) | |
2417 | return ret; | |
2418 | ||
2419 | ret = ring_buffer_resize(max_tr.buffer, size); | |
2420 | if (ret < 0) { | |
2421 | int r; | |
2422 | ||
2423 | r = ring_buffer_resize(global_trace.buffer, | |
2424 | global_trace.entries); | |
2425 | if (r < 0) { | |
a123c52b SR |
2426 | /* |
2427 | * AARGH! We are left with different | |
2428 | * size max buffer!!!! | |
2429 | * The max buffer is our "snapshot" buffer. | |
2430 | * When a tracer needs a snapshot (one of the | |
2431 | * latency tracers), it swaps the max buffer | |
2432 | * with the saved snap shot. We succeeded to | |
2433 | * update the size of the main buffer, but failed to | |
2434 | * update the size of the max buffer. But when we tried | |
2435 | * to reset the main buffer to the original size, we | |
2436 | * failed there too. This is very unlikely to | |
2437 | * happen, but if it does, warn and kill all | |
2438 | * tracing. | |
2439 | */ | |
73c5162a SR |
2440 | WARN_ON(1); |
2441 | tracing_disabled = 1; | |
2442 | } | |
2443 | return ret; | |
2444 | } | |
2445 | ||
2446 | global_trace.entries = size; | |
2447 | ||
2448 | return ret; | |
2449 | } | |
2450 | ||
1852fcce SR |
2451 | /** |
2452 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2453 | * | |
2454 | * To save on memory when the tracing is never used on a system with it | |
2455 | * configured in. The ring buffers are set to a minimum size. But once | |
2456 | * a user starts to use the tracing facility, then they need to grow | |
2457 | * to their default size. | |
2458 | * | |
2459 | * This function is to be called when a tracer is about to be used. | |
2460 | */ | |
2461 | int tracing_update_buffers(void) | |
2462 | { | |
2463 | int ret = 0; | |
2464 | ||
1027fcb2 | 2465 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2466 | if (!ring_buffer_expanded) |
2467 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2468 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2469 | |
2470 | return ret; | |
2471 | } | |
2472 | ||
577b785f SR |
2473 | struct trace_option_dentry; |
2474 | ||
2475 | static struct trace_option_dentry * | |
2476 | create_trace_option_files(struct tracer *tracer); | |
2477 | ||
2478 | static void | |
2479 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2480 | ||
b2821ae6 | 2481 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2482 | { |
577b785f | 2483 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2484 | struct trace_array *tr = &global_trace; |
2485 | struct tracer *t; | |
d9e54076 | 2486 | int ret = 0; |
bc0c38d1 | 2487 | |
1027fcb2 SR |
2488 | mutex_lock(&trace_types_lock); |
2489 | ||
73c5162a SR |
2490 | if (!ring_buffer_expanded) { |
2491 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2492 | if (ret < 0) | |
59f586db | 2493 | goto out; |
73c5162a SR |
2494 | ret = 0; |
2495 | } | |
2496 | ||
bc0c38d1 SR |
2497 | for (t = trace_types; t; t = t->next) { |
2498 | if (strcmp(t->name, buf) == 0) | |
2499 | break; | |
2500 | } | |
c2931e05 FW |
2501 | if (!t) { |
2502 | ret = -EINVAL; | |
2503 | goto out; | |
2504 | } | |
2505 | if (t == current_trace) | |
bc0c38d1 SR |
2506 | goto out; |
2507 | ||
9f029e83 | 2508 | trace_branch_disable(); |
bc0c38d1 SR |
2509 | if (current_trace && current_trace->reset) |
2510 | current_trace->reset(tr); | |
2511 | ||
577b785f SR |
2512 | destroy_trace_option_files(topts); |
2513 | ||
bc0c38d1 | 2514 | current_trace = t; |
577b785f SR |
2515 | |
2516 | topts = create_trace_option_files(current_trace); | |
2517 | ||
1c80025a | 2518 | if (t->init) { |
b6f11df2 | 2519 | ret = tracer_init(t, tr); |
1c80025a FW |
2520 | if (ret) |
2521 | goto out; | |
2522 | } | |
bc0c38d1 | 2523 | |
9f029e83 | 2524 | trace_branch_enable(tr); |
bc0c38d1 SR |
2525 | out: |
2526 | mutex_unlock(&trace_types_lock); | |
2527 | ||
d9e54076 PZ |
2528 | return ret; |
2529 | } | |
2530 | ||
2531 | static ssize_t | |
2532 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2533 | size_t cnt, loff_t *ppos) | |
2534 | { | |
2535 | char buf[max_tracer_type_len+1]; | |
2536 | int i; | |
2537 | size_t ret; | |
e6e7a65a FW |
2538 | int err; |
2539 | ||
2540 | ret = cnt; | |
d9e54076 PZ |
2541 | |
2542 | if (cnt > max_tracer_type_len) | |
2543 | cnt = max_tracer_type_len; | |
2544 | ||
2545 | if (copy_from_user(&buf, ubuf, cnt)) | |
2546 | return -EFAULT; | |
2547 | ||
2548 | buf[cnt] = 0; | |
2549 | ||
2550 | /* strip ending whitespace. */ | |
2551 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2552 | buf[i] = 0; | |
2553 | ||
e6e7a65a FW |
2554 | err = tracing_set_tracer(buf); |
2555 | if (err) | |
2556 | return err; | |
d9e54076 | 2557 | |
e6e7a65a | 2558 | filp->f_pos += ret; |
bc0c38d1 | 2559 | |
c2931e05 | 2560 | return ret; |
bc0c38d1 SR |
2561 | } |
2562 | ||
2563 | static ssize_t | |
2564 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2565 | size_t cnt, loff_t *ppos) | |
2566 | { | |
2567 | unsigned long *ptr = filp->private_data; | |
2568 | char buf[64]; | |
2569 | int r; | |
2570 | ||
cffae437 | 2571 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2572 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2573 | if (r > sizeof(buf)) |
2574 | r = sizeof(buf); | |
4bf39a94 | 2575 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2576 | } |
2577 | ||
2578 | static ssize_t | |
2579 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2580 | size_t cnt, loff_t *ppos) | |
2581 | { | |
5e39841c | 2582 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2583 | char buf[64]; |
5e39841c | 2584 | unsigned long val; |
c6caeeb1 | 2585 | int ret; |
bc0c38d1 | 2586 | |
cffae437 SR |
2587 | if (cnt >= sizeof(buf)) |
2588 | return -EINVAL; | |
bc0c38d1 SR |
2589 | |
2590 | if (copy_from_user(&buf, ubuf, cnt)) | |
2591 | return -EFAULT; | |
2592 | ||
2593 | buf[cnt] = 0; | |
2594 | ||
c6caeeb1 SR |
2595 | ret = strict_strtoul(buf, 10, &val); |
2596 | if (ret < 0) | |
2597 | return ret; | |
bc0c38d1 SR |
2598 | |
2599 | *ptr = val * 1000; | |
2600 | ||
2601 | return cnt; | |
2602 | } | |
2603 | ||
b3806b43 SR |
2604 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2605 | { | |
b04cc6b1 | 2606 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2607 | struct trace_iterator *iter; |
b04cc6b1 | 2608 | int ret = 0; |
b3806b43 SR |
2609 | |
2610 | if (tracing_disabled) | |
2611 | return -ENODEV; | |
2612 | ||
b04cc6b1 FW |
2613 | mutex_lock(&trace_types_lock); |
2614 | ||
2615 | /* We only allow one reader per cpu */ | |
2616 | if (cpu_file == TRACE_PIPE_ALL_CPU) { | |
2617 | if (!cpumask_empty(tracing_reader_cpumask)) { | |
2618 | ret = -EBUSY; | |
2619 | goto out; | |
2620 | } | |
2621 | cpumask_setall(tracing_reader_cpumask); | |
2622 | } else { | |
2623 | if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask)) | |
2624 | cpumask_set_cpu(cpu_file, tracing_reader_cpumask); | |
2625 | else { | |
2626 | ret = -EBUSY; | |
2627 | goto out; | |
2628 | } | |
b3806b43 SR |
2629 | } |
2630 | ||
2631 | /* create a buffer to store the information to pass to userspace */ | |
2632 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2633 | if (!iter) { |
2634 | ret = -ENOMEM; | |
2635 | goto out; | |
2636 | } | |
b3806b43 | 2637 | |
d7350c3f FW |
2638 | /* |
2639 | * We make a copy of the current tracer to avoid concurrent | |
2640 | * changes on it while we are reading. | |
2641 | */ | |
2642 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
2643 | if (!iter->trace) { | |
2644 | ret = -ENOMEM; | |
2645 | goto fail; | |
2646 | } | |
2647 | if (current_trace) | |
2648 | *iter->trace = *current_trace; | |
2649 | ||
4462344e | 2650 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 2651 | ret = -ENOMEM; |
d7350c3f | 2652 | goto fail; |
4462344e RR |
2653 | } |
2654 | ||
a309720c | 2655 | /* trace pipe does not show start of buffer */ |
4462344e | 2656 | cpumask_setall(iter->started); |
a309720c | 2657 | |
112f38a7 SR |
2658 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
2659 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2660 | ||
b04cc6b1 | 2661 | iter->cpu_file = cpu_file; |
b3806b43 | 2662 | iter->tr = &global_trace; |
d7350c3f | 2663 | mutex_init(&iter->mutex); |
b3806b43 SR |
2664 | filp->private_data = iter; |
2665 | ||
107bad8b SR |
2666 | if (iter->trace->pipe_open) |
2667 | iter->trace->pipe_open(iter); | |
107bad8b | 2668 | |
b04cc6b1 FW |
2669 | out: |
2670 | mutex_unlock(&trace_types_lock); | |
2671 | return ret; | |
d7350c3f FW |
2672 | |
2673 | fail: | |
2674 | kfree(iter->trace); | |
2675 | kfree(iter); | |
2676 | mutex_unlock(&trace_types_lock); | |
2677 | return ret; | |
b3806b43 SR |
2678 | } |
2679 | ||
2680 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2681 | { | |
2682 | struct trace_iterator *iter = file->private_data; | |
2683 | ||
b04cc6b1 FW |
2684 | mutex_lock(&trace_types_lock); |
2685 | ||
2686 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) | |
2687 | cpumask_clear(tracing_reader_cpumask); | |
2688 | else | |
2689 | cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); | |
2690 | ||
2691 | mutex_unlock(&trace_types_lock); | |
2692 | ||
4462344e | 2693 | free_cpumask_var(iter->started); |
d7350c3f FW |
2694 | mutex_destroy(&iter->mutex); |
2695 | kfree(iter->trace); | |
b3806b43 | 2696 | kfree(iter); |
b3806b43 SR |
2697 | |
2698 | return 0; | |
2699 | } | |
2700 | ||
2a2cc8f7 SSP |
2701 | static unsigned int |
2702 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2703 | { | |
2704 | struct trace_iterator *iter = filp->private_data; | |
2705 | ||
2706 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2707 | /* | |
2708 | * Always select as readable when in blocking mode | |
2709 | */ | |
2710 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2711 | } else { |
2a2cc8f7 SSP |
2712 | if (!trace_empty(iter)) |
2713 | return POLLIN | POLLRDNORM; | |
2714 | poll_wait(filp, &trace_wait, poll_table); | |
2715 | if (!trace_empty(iter)) | |
2716 | return POLLIN | POLLRDNORM; | |
2717 | ||
2718 | return 0; | |
2719 | } | |
2720 | } | |
2721 | ||
6eaaa5d5 FW |
2722 | |
2723 | void default_wait_pipe(struct trace_iterator *iter) | |
2724 | { | |
2725 | DEFINE_WAIT(wait); | |
2726 | ||
2727 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
2728 | ||
2729 | if (trace_empty(iter)) | |
2730 | schedule(); | |
2731 | ||
2732 | finish_wait(&trace_wait, &wait); | |
2733 | } | |
2734 | ||
2735 | /* | |
2736 | * This is a make-shift waitqueue. | |
2737 | * A tracer might use this callback on some rare cases: | |
2738 | * | |
2739 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
2740 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
2741 | * 2) the function tracers, trace all functions, we don't want | |
2742 | * the overhead of calling wake_up and friends | |
2743 | * (and tracing them too) | |
2744 | * | |
2745 | * Anyway, this is really very primitive wakeup. | |
2746 | */ | |
2747 | void poll_wait_pipe(struct trace_iterator *iter) | |
2748 | { | |
2749 | set_current_state(TASK_INTERRUPTIBLE); | |
2750 | /* sleep for 100 msecs, and try again. */ | |
2751 | schedule_timeout(HZ / 10); | |
2752 | } | |
2753 | ||
ff98781b EGM |
2754 | /* Must be called with trace_types_lock mutex held. */ |
2755 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
2756 | { |
2757 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 2758 | |
b3806b43 | 2759 | while (trace_empty(iter)) { |
2dc8f095 | 2760 | |
107bad8b | 2761 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 2762 | return -EAGAIN; |
107bad8b | 2763 | } |
2dc8f095 | 2764 | |
d7350c3f | 2765 | mutex_unlock(&iter->mutex); |
107bad8b | 2766 | |
6eaaa5d5 | 2767 | iter->trace->wait_pipe(iter); |
b3806b43 | 2768 | |
d7350c3f | 2769 | mutex_lock(&iter->mutex); |
107bad8b | 2770 | |
6eaaa5d5 | 2771 | if (signal_pending(current)) |
ff98781b | 2772 | return -EINTR; |
b3806b43 SR |
2773 | |
2774 | /* | |
2775 | * We block until we read something and tracing is disabled. | |
2776 | * We still block if tracing is disabled, but we have never | |
2777 | * read anything. This allows a user to cat this file, and | |
2778 | * then enable tracing. But after we have read something, | |
2779 | * we give an EOF when tracing is again disabled. | |
2780 | * | |
2781 | * iter->pos will be 0 if we haven't read anything. | |
2782 | */ | |
2783 | if (!tracer_enabled && iter->pos) | |
2784 | break; | |
b3806b43 SR |
2785 | } |
2786 | ||
ff98781b EGM |
2787 | return 1; |
2788 | } | |
2789 | ||
2790 | /* | |
2791 | * Consumer reader. | |
2792 | */ | |
2793 | static ssize_t | |
2794 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2795 | size_t cnt, loff_t *ppos) | |
2796 | { | |
2797 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 2798 | static struct tracer *old_tracer; |
ff98781b EGM |
2799 | ssize_t sret; |
2800 | ||
2801 | /* return any leftover data */ | |
2802 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
2803 | if (sret != -EBUSY) | |
2804 | return sret; | |
2805 | ||
f9520750 | 2806 | trace_seq_init(&iter->seq); |
ff98781b | 2807 | |
d7350c3f | 2808 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 2809 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2810 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2811 | old_tracer = current_trace; | |
2812 | *iter->trace = *current_trace; | |
2813 | } | |
2814 | mutex_unlock(&trace_types_lock); | |
2815 | ||
2816 | /* | |
2817 | * Avoid more than one consumer on a single file descriptor | |
2818 | * This is just a matter of traces coherency, the ring buffer itself | |
2819 | * is protected. | |
2820 | */ | |
2821 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
2822 | if (iter->trace->read) { |
2823 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
2824 | if (sret) | |
2825 | goto out; | |
2826 | } | |
2827 | ||
2828 | waitagain: | |
2829 | sret = tracing_wait_pipe(filp); | |
2830 | if (sret <= 0) | |
2831 | goto out; | |
2832 | ||
b3806b43 | 2833 | /* stop when tracing is finished */ |
ff98781b EGM |
2834 | if (trace_empty(iter)) { |
2835 | sret = 0; | |
107bad8b | 2836 | goto out; |
ff98781b | 2837 | } |
b3806b43 SR |
2838 | |
2839 | if (cnt >= PAGE_SIZE) | |
2840 | cnt = PAGE_SIZE - 1; | |
2841 | ||
53d0aa77 | 2842 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
2843 | memset(&iter->seq, 0, |
2844 | sizeof(struct trace_iterator) - | |
2845 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 2846 | iter->pos = -1; |
b3806b43 | 2847 | |
4f535968 | 2848 | trace_event_read_lock(); |
088b1e42 | 2849 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 2850 | enum print_line_t ret; |
088b1e42 SR |
2851 | int len = iter->seq.len; |
2852 | ||
f9896bf3 | 2853 | ret = print_trace_line(iter); |
2c4f035f | 2854 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
2855 | /* don't print partial lines */ |
2856 | iter->seq.len = len; | |
b3806b43 | 2857 | break; |
088b1e42 | 2858 | } |
b91facc3 FW |
2859 | if (ret != TRACE_TYPE_NO_CONSUME) |
2860 | trace_consume(iter); | |
b3806b43 SR |
2861 | |
2862 | if (iter->seq.len >= cnt) | |
2863 | break; | |
b3806b43 | 2864 | } |
4f535968 | 2865 | trace_event_read_unlock(); |
b3806b43 | 2866 | |
b3806b43 | 2867 | /* Now copy what we have to the user */ |
6c6c2796 PP |
2868 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2869 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 2870 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
2871 | |
2872 | /* | |
2873 | * If there was nothing to send to user, inspite of consuming trace | |
2874 | * entries, go back to wait for more entries. | |
2875 | */ | |
6c6c2796 | 2876 | if (sret == -EBUSY) |
9ff4b974 | 2877 | goto waitagain; |
b3806b43 | 2878 | |
107bad8b | 2879 | out: |
d7350c3f | 2880 | mutex_unlock(&iter->mutex); |
107bad8b | 2881 | |
6c6c2796 | 2882 | return sret; |
b3806b43 SR |
2883 | } |
2884 | ||
3c56819b EGM |
2885 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
2886 | struct pipe_buffer *buf) | |
2887 | { | |
2888 | __free_page(buf->page); | |
2889 | } | |
2890 | ||
2891 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
2892 | unsigned int idx) | |
2893 | { | |
2894 | __free_page(spd->pages[idx]); | |
2895 | } | |
2896 | ||
2897 | static struct pipe_buf_operations tracing_pipe_buf_ops = { | |
34cd4998 SR |
2898 | .can_merge = 0, |
2899 | .map = generic_pipe_buf_map, | |
2900 | .unmap = generic_pipe_buf_unmap, | |
2901 | .confirm = generic_pipe_buf_confirm, | |
2902 | .release = tracing_pipe_buf_release, | |
2903 | .steal = generic_pipe_buf_steal, | |
2904 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
2905 | }; |
2906 | ||
34cd4998 | 2907 | static size_t |
fa7c7f6e | 2908 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
2909 | { |
2910 | size_t count; | |
2911 | int ret; | |
2912 | ||
2913 | /* Seq buffer is page-sized, exactly what we need. */ | |
2914 | for (;;) { | |
2915 | count = iter->seq.len; | |
2916 | ret = print_trace_line(iter); | |
2917 | count = iter->seq.len - count; | |
2918 | if (rem < count) { | |
2919 | rem = 0; | |
2920 | iter->seq.len -= count; | |
2921 | break; | |
2922 | } | |
2923 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
2924 | iter->seq.len -= count; | |
2925 | break; | |
2926 | } | |
2927 | ||
74e7ff8c LJ |
2928 | if (ret != TRACE_TYPE_NO_CONSUME) |
2929 | trace_consume(iter); | |
34cd4998 SR |
2930 | rem -= count; |
2931 | if (!find_next_entry_inc(iter)) { | |
2932 | rem = 0; | |
2933 | iter->ent = NULL; | |
2934 | break; | |
2935 | } | |
2936 | } | |
2937 | ||
2938 | return rem; | |
2939 | } | |
2940 | ||
3c56819b EGM |
2941 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
2942 | loff_t *ppos, | |
2943 | struct pipe_inode_info *pipe, | |
2944 | size_t len, | |
2945 | unsigned int flags) | |
2946 | { | |
2947 | struct page *pages[PIPE_BUFFERS]; | |
2948 | struct partial_page partial[PIPE_BUFFERS]; | |
2949 | struct trace_iterator *iter = filp->private_data; | |
2950 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
2951 | .pages = pages, |
2952 | .partial = partial, | |
2953 | .nr_pages = 0, /* This gets updated below. */ | |
2954 | .flags = flags, | |
2955 | .ops = &tracing_pipe_buf_ops, | |
2956 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 2957 | }; |
d7350c3f | 2958 | static struct tracer *old_tracer; |
3c56819b | 2959 | ssize_t ret; |
34cd4998 | 2960 | size_t rem; |
3c56819b EGM |
2961 | unsigned int i; |
2962 | ||
d7350c3f | 2963 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 2964 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2965 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2966 | old_tracer = current_trace; | |
2967 | *iter->trace = *current_trace; | |
2968 | } | |
2969 | mutex_unlock(&trace_types_lock); | |
2970 | ||
2971 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
2972 | |
2973 | if (iter->trace->splice_read) { | |
2974 | ret = iter->trace->splice_read(iter, filp, | |
2975 | ppos, pipe, len, flags); | |
2976 | if (ret) | |
34cd4998 | 2977 | goto out_err; |
3c56819b EGM |
2978 | } |
2979 | ||
2980 | ret = tracing_wait_pipe(filp); | |
2981 | if (ret <= 0) | |
34cd4998 | 2982 | goto out_err; |
3c56819b EGM |
2983 | |
2984 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
2985 | ret = -EFAULT; | |
34cd4998 | 2986 | goto out_err; |
3c56819b EGM |
2987 | } |
2988 | ||
4f535968 LJ |
2989 | trace_event_read_lock(); |
2990 | ||
3c56819b EGM |
2991 | /* Fill as many pages as possible. */ |
2992 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
2993 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
2994 | if (!pages[i]) |
2995 | break; | |
3c56819b | 2996 | |
fa7c7f6e | 2997 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
2998 | |
2999 | /* Copy the data into the page, so we can start over. */ | |
3000 | ret = trace_seq_to_buffer(&iter->seq, | |
3001 | page_address(pages[i]), | |
3002 | iter->seq.len); | |
3003 | if (ret < 0) { | |
3004 | __free_page(pages[i]); | |
3005 | break; | |
3006 | } | |
3007 | partial[i].offset = 0; | |
3008 | partial[i].len = iter->seq.len; | |
3009 | ||
f9520750 | 3010 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3011 | } |
3012 | ||
4f535968 | 3013 | trace_event_read_unlock(); |
d7350c3f | 3014 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3015 | |
3016 | spd.nr_pages = i; | |
3017 | ||
3018 | return splice_to_pipe(pipe, &spd); | |
3019 | ||
34cd4998 | 3020 | out_err: |
d7350c3f | 3021 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3022 | |
3023 | return ret; | |
3024 | } | |
3025 | ||
a98a3c3f SR |
3026 | static ssize_t |
3027 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3028 | size_t cnt, loff_t *ppos) | |
3029 | { | |
3030 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3031 | char buf[96]; |
a98a3c3f SR |
3032 | int r; |
3033 | ||
db526ca3 SR |
3034 | mutex_lock(&trace_types_lock); |
3035 | if (!ring_buffer_expanded) | |
3036 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3037 | tr->entries >> 10, | |
3038 | trace_buf_size >> 10); | |
3039 | else | |
3040 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3041 | mutex_unlock(&trace_types_lock); | |
3042 | ||
a98a3c3f SR |
3043 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3044 | } | |
3045 | ||
3046 | static ssize_t | |
3047 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3048 | size_t cnt, loff_t *ppos) | |
3049 | { | |
3050 | unsigned long val; | |
3051 | char buf[64]; | |
bf5e6519 | 3052 | int ret, cpu; |
a98a3c3f | 3053 | |
cffae437 SR |
3054 | if (cnt >= sizeof(buf)) |
3055 | return -EINVAL; | |
a98a3c3f SR |
3056 | |
3057 | if (copy_from_user(&buf, ubuf, cnt)) | |
3058 | return -EFAULT; | |
3059 | ||
3060 | buf[cnt] = 0; | |
3061 | ||
c6caeeb1 SR |
3062 | ret = strict_strtoul(buf, 10, &val); |
3063 | if (ret < 0) | |
3064 | return ret; | |
a98a3c3f SR |
3065 | |
3066 | /* must have at least 1 entry */ | |
3067 | if (!val) | |
3068 | return -EINVAL; | |
3069 | ||
3070 | mutex_lock(&trace_types_lock); | |
3071 | ||
c76f0694 | 3072 | tracing_stop(); |
a98a3c3f | 3073 | |
bf5e6519 SR |
3074 | /* disable all cpu buffers */ |
3075 | for_each_tracing_cpu(cpu) { | |
3076 | if (global_trace.data[cpu]) | |
3077 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3078 | if (max_tr.data[cpu]) | |
3079 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3080 | } | |
3081 | ||
1696b2b0 SR |
3082 | /* value is in KB */ |
3083 | val <<= 10; | |
3084 | ||
3928a8a2 | 3085 | if (val != global_trace.entries) { |
73c5162a | 3086 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3087 | if (ret < 0) { |
3088 | cnt = ret; | |
3eefae99 SR |
3089 | goto out; |
3090 | } | |
a98a3c3f SR |
3091 | } |
3092 | ||
3093 | filp->f_pos += cnt; | |
3094 | ||
19384c03 SR |
3095 | /* If check pages failed, return ENOMEM */ |
3096 | if (tracing_disabled) | |
3097 | cnt = -ENOMEM; | |
a98a3c3f | 3098 | out: |
bf5e6519 SR |
3099 | for_each_tracing_cpu(cpu) { |
3100 | if (global_trace.data[cpu]) | |
3101 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3102 | if (max_tr.data[cpu]) | |
3103 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3104 | } | |
3105 | ||
c76f0694 | 3106 | tracing_start(); |
a98a3c3f SR |
3107 | max_tr.entries = global_trace.entries; |
3108 | mutex_unlock(&trace_types_lock); | |
3109 | ||
3110 | return cnt; | |
3111 | } | |
3112 | ||
5bf9a1ee PP |
3113 | static int mark_printk(const char *fmt, ...) |
3114 | { | |
3115 | int ret; | |
3116 | va_list args; | |
3117 | va_start(args, fmt); | |
40ce74f1 | 3118 | ret = trace_vprintk(0, fmt, args); |
5bf9a1ee PP |
3119 | va_end(args); |
3120 | return ret; | |
3121 | } | |
3122 | ||
3123 | static ssize_t | |
3124 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3125 | size_t cnt, loff_t *fpos) | |
3126 | { | |
3127 | char *buf; | |
3128 | char *end; | |
5bf9a1ee | 3129 | |
c76f0694 | 3130 | if (tracing_disabled) |
5bf9a1ee PP |
3131 | return -EINVAL; |
3132 | ||
3133 | if (cnt > TRACE_BUF_SIZE) | |
3134 | cnt = TRACE_BUF_SIZE; | |
3135 | ||
3136 | buf = kmalloc(cnt + 1, GFP_KERNEL); | |
3137 | if (buf == NULL) | |
3138 | return -ENOMEM; | |
3139 | ||
3140 | if (copy_from_user(buf, ubuf, cnt)) { | |
3141 | kfree(buf); | |
3142 | return -EFAULT; | |
3143 | } | |
3144 | ||
3145 | /* Cut from the first nil or newline. */ | |
3146 | buf[cnt] = '\0'; | |
3147 | end = strchr(buf, '\n'); | |
3148 | if (end) | |
3149 | *end = '\0'; | |
3150 | ||
3151 | cnt = mark_printk("%s\n", buf); | |
3152 | kfree(buf); | |
3153 | *fpos += cnt; | |
3154 | ||
3155 | return cnt; | |
3156 | } | |
3157 | ||
5079f326 Z |
3158 | static ssize_t tracing_clock_read(struct file *filp, char __user *ubuf, |
3159 | size_t cnt, loff_t *ppos) | |
3160 | { | |
3161 | char buf[64]; | |
3162 | int bufiter = 0; | |
3163 | int i; | |
3164 | ||
3165 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
3166 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, | |
3167 | "%s%s%s%s", i ? " " : "", | |
3168 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3169 | i == trace_clock_id ? "]" : ""); | |
3170 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, "\n"); | |
3171 | ||
3172 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, bufiter); | |
3173 | } | |
3174 | ||
3175 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
3176 | size_t cnt, loff_t *fpos) | |
3177 | { | |
3178 | char buf[64]; | |
3179 | const char *clockstr; | |
3180 | int i; | |
3181 | ||
3182 | if (cnt >= sizeof(buf)) | |
3183 | return -EINVAL; | |
3184 | ||
3185 | if (copy_from_user(&buf, ubuf, cnt)) | |
3186 | return -EFAULT; | |
3187 | ||
3188 | buf[cnt] = 0; | |
3189 | ||
3190 | clockstr = strstrip(buf); | |
3191 | ||
3192 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
3193 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
3194 | break; | |
3195 | } | |
3196 | if (i == ARRAY_SIZE(trace_clocks)) | |
3197 | return -EINVAL; | |
3198 | ||
3199 | trace_clock_id = i; | |
3200 | ||
3201 | mutex_lock(&trace_types_lock); | |
3202 | ||
3203 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
3204 | if (max_tr.buffer) | |
3205 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
3206 | ||
3207 | mutex_unlock(&trace_types_lock); | |
3208 | ||
3209 | *fpos += cnt; | |
3210 | ||
3211 | return cnt; | |
3212 | } | |
3213 | ||
5e2336a0 | 3214 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3215 | .open = tracing_open_generic, |
3216 | .read = tracing_max_lat_read, | |
3217 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
3218 | }; |
3219 | ||
5e2336a0 | 3220 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3221 | .open = tracing_open_generic, |
3222 | .read = tracing_ctrl_read, | |
3223 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
3224 | }; |
3225 | ||
5e2336a0 | 3226 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3227 | .open = tracing_open_generic, |
3228 | .read = tracing_set_trace_read, | |
3229 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
3230 | }; |
3231 | ||
5e2336a0 | 3232 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3233 | .open = tracing_open_pipe, |
2a2cc8f7 | 3234 | .poll = tracing_poll_pipe, |
4bf39a94 | 3235 | .read = tracing_read_pipe, |
3c56819b | 3236 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3237 | .release = tracing_release_pipe, |
b3806b43 SR |
3238 | }; |
3239 | ||
5e2336a0 | 3240 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3241 | .open = tracing_open_generic, |
3242 | .read = tracing_entries_read, | |
3243 | .write = tracing_entries_write, | |
3244 | }; | |
3245 | ||
5e2336a0 | 3246 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3247 | .open = tracing_open_generic, |
5bf9a1ee PP |
3248 | .write = tracing_mark_write, |
3249 | }; | |
3250 | ||
5079f326 Z |
3251 | static const struct file_operations trace_clock_fops = { |
3252 | .open = tracing_open_generic, | |
3253 | .read = tracing_clock_read, | |
3254 | .write = tracing_clock_write, | |
3255 | }; | |
3256 | ||
2cadf913 SR |
3257 | struct ftrace_buffer_info { |
3258 | struct trace_array *tr; | |
3259 | void *spare; | |
3260 | int cpu; | |
3261 | unsigned int read; | |
3262 | }; | |
3263 | ||
3264 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3265 | { | |
3266 | int cpu = (int)(long)inode->i_private; | |
3267 | struct ftrace_buffer_info *info; | |
3268 | ||
3269 | if (tracing_disabled) | |
3270 | return -ENODEV; | |
3271 | ||
3272 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3273 | if (!info) | |
3274 | return -ENOMEM; | |
3275 | ||
3276 | info->tr = &global_trace; | |
3277 | info->cpu = cpu; | |
ddd538f3 | 3278 | info->spare = NULL; |
2cadf913 SR |
3279 | /* Force reading ring buffer for first read */ |
3280 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3281 | |
3282 | filp->private_data = info; | |
3283 | ||
d1e7e02f | 3284 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3285 | } |
3286 | ||
3287 | static ssize_t | |
3288 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3289 | size_t count, loff_t *ppos) | |
3290 | { | |
3291 | struct ftrace_buffer_info *info = filp->private_data; | |
3292 | unsigned int pos; | |
3293 | ssize_t ret; | |
3294 | size_t size; | |
3295 | ||
2dc5d12b SR |
3296 | if (!count) |
3297 | return 0; | |
3298 | ||
ddd538f3 LJ |
3299 | if (!info->spare) |
3300 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3301 | if (!info->spare) | |
3302 | return -ENOMEM; | |
3303 | ||
2cadf913 SR |
3304 | /* Do we have previous read data to read? */ |
3305 | if (info->read < PAGE_SIZE) | |
3306 | goto read; | |
3307 | ||
3308 | info->read = 0; | |
3309 | ||
3310 | ret = ring_buffer_read_page(info->tr->buffer, | |
3311 | &info->spare, | |
3312 | count, | |
3313 | info->cpu, 0); | |
3314 | if (ret < 0) | |
3315 | return 0; | |
3316 | ||
3317 | pos = ring_buffer_page_len(info->spare); | |
3318 | ||
3319 | if (pos < PAGE_SIZE) | |
3320 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3321 | ||
3322 | read: | |
3323 | size = PAGE_SIZE - info->read; | |
3324 | if (size > count) | |
3325 | size = count; | |
3326 | ||
3327 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3328 | if (ret == size) |
2cadf913 | 3329 | return -EFAULT; |
2dc5d12b SR |
3330 | size -= ret; |
3331 | ||
2cadf913 SR |
3332 | *ppos += size; |
3333 | info->read += size; | |
3334 | ||
3335 | return size; | |
3336 | } | |
3337 | ||
3338 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3339 | { | |
3340 | struct ftrace_buffer_info *info = file->private_data; | |
3341 | ||
ddd538f3 LJ |
3342 | if (info->spare) |
3343 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3344 | kfree(info); |
3345 | ||
3346 | return 0; | |
3347 | } | |
3348 | ||
3349 | struct buffer_ref { | |
3350 | struct ring_buffer *buffer; | |
3351 | void *page; | |
3352 | int ref; | |
3353 | }; | |
3354 | ||
3355 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3356 | struct pipe_buffer *buf) | |
3357 | { | |
3358 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3359 | ||
3360 | if (--ref->ref) | |
3361 | return; | |
3362 | ||
3363 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3364 | kfree(ref); | |
3365 | buf->private = 0; | |
3366 | } | |
3367 | ||
3368 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3369 | struct pipe_buffer *buf) | |
3370 | { | |
3371 | return 1; | |
3372 | } | |
3373 | ||
3374 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3375 | struct pipe_buffer *buf) | |
3376 | { | |
3377 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3378 | ||
3379 | ref->ref++; | |
3380 | } | |
3381 | ||
3382 | /* Pipe buffer operations for a buffer. */ | |
3383 | static struct pipe_buf_operations buffer_pipe_buf_ops = { | |
3384 | .can_merge = 0, | |
3385 | .map = generic_pipe_buf_map, | |
3386 | .unmap = generic_pipe_buf_unmap, | |
3387 | .confirm = generic_pipe_buf_confirm, | |
3388 | .release = buffer_pipe_buf_release, | |
3389 | .steal = buffer_pipe_buf_steal, | |
3390 | .get = buffer_pipe_buf_get, | |
3391 | }; | |
3392 | ||
3393 | /* | |
3394 | * Callback from splice_to_pipe(), if we need to release some pages | |
3395 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3396 | */ | |
3397 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3398 | { | |
3399 | struct buffer_ref *ref = | |
3400 | (struct buffer_ref *)spd->partial[i].private; | |
3401 | ||
3402 | if (--ref->ref) | |
3403 | return; | |
3404 | ||
3405 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3406 | kfree(ref); | |
3407 | spd->partial[i].private = 0; | |
3408 | } | |
3409 | ||
3410 | static ssize_t | |
3411 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3412 | struct pipe_inode_info *pipe, size_t len, | |
3413 | unsigned int flags) | |
3414 | { | |
3415 | struct ftrace_buffer_info *info = file->private_data; | |
3416 | struct partial_page partial[PIPE_BUFFERS]; | |
3417 | struct page *pages[PIPE_BUFFERS]; | |
3418 | struct splice_pipe_desc spd = { | |
3419 | .pages = pages, | |
3420 | .partial = partial, | |
3421 | .flags = flags, | |
3422 | .ops = &buffer_pipe_buf_ops, | |
3423 | .spd_release = buffer_spd_release, | |
3424 | }; | |
3425 | struct buffer_ref *ref; | |
93459c6c | 3426 | int entries, size, i; |
2cadf913 SR |
3427 | size_t ret; |
3428 | ||
93cfb3c9 LJ |
3429 | if (*ppos & (PAGE_SIZE - 1)) { |
3430 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
3431 | return -EINVAL; | |
3432 | } | |
3433 | ||
3434 | if (len & (PAGE_SIZE - 1)) { | |
3435 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
3436 | if (len < PAGE_SIZE) | |
3437 | return -EINVAL; | |
3438 | len &= PAGE_MASK; | |
3439 | } | |
3440 | ||
93459c6c SR |
3441 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
3442 | ||
3443 | for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) { | |
2cadf913 SR |
3444 | struct page *page; |
3445 | int r; | |
3446 | ||
3447 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3448 | if (!ref) | |
3449 | break; | |
3450 | ||
7267fa68 | 3451 | ref->ref = 1; |
2cadf913 SR |
3452 | ref->buffer = info->tr->buffer; |
3453 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3454 | if (!ref->page) { | |
3455 | kfree(ref); | |
3456 | break; | |
3457 | } | |
3458 | ||
3459 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 3460 | len, info->cpu, 1); |
2cadf913 SR |
3461 | if (r < 0) { |
3462 | ring_buffer_free_read_page(ref->buffer, | |
3463 | ref->page); | |
3464 | kfree(ref); | |
3465 | break; | |
3466 | } | |
3467 | ||
3468 | /* | |
3469 | * zero out any left over data, this is going to | |
3470 | * user land. | |
3471 | */ | |
3472 | size = ring_buffer_page_len(ref->page); | |
3473 | if (size < PAGE_SIZE) | |
3474 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3475 | ||
3476 | page = virt_to_page(ref->page); | |
3477 | ||
3478 | spd.pages[i] = page; | |
3479 | spd.partial[i].len = PAGE_SIZE; | |
3480 | spd.partial[i].offset = 0; | |
3481 | spd.partial[i].private = (unsigned long)ref; | |
3482 | spd.nr_pages++; | |
93cfb3c9 | 3483 | *ppos += PAGE_SIZE; |
93459c6c SR |
3484 | |
3485 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
3486 | } |
3487 | ||
3488 | spd.nr_pages = i; | |
3489 | ||
3490 | /* did we read anything? */ | |
3491 | if (!spd.nr_pages) { | |
3492 | if (flags & SPLICE_F_NONBLOCK) | |
3493 | ret = -EAGAIN; | |
3494 | else | |
3495 | ret = 0; | |
3496 | /* TODO: block */ | |
3497 | return ret; | |
3498 | } | |
3499 | ||
3500 | ret = splice_to_pipe(pipe, &spd); | |
3501 | ||
3502 | return ret; | |
3503 | } | |
3504 | ||
3505 | static const struct file_operations tracing_buffers_fops = { | |
3506 | .open = tracing_buffers_open, | |
3507 | .read = tracing_buffers_read, | |
3508 | .release = tracing_buffers_release, | |
3509 | .splice_read = tracing_buffers_splice_read, | |
3510 | .llseek = no_llseek, | |
3511 | }; | |
3512 | ||
c8d77183 SR |
3513 | static ssize_t |
3514 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
3515 | size_t count, loff_t *ppos) | |
3516 | { | |
3517 | unsigned long cpu = (unsigned long)filp->private_data; | |
3518 | struct trace_array *tr = &global_trace; | |
3519 | struct trace_seq *s; | |
3520 | unsigned long cnt; | |
3521 | ||
e4f2d10f | 3522 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 SR |
3523 | if (!s) |
3524 | return ENOMEM; | |
3525 | ||
3526 | trace_seq_init(s); | |
3527 | ||
3528 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
3529 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
3530 | ||
3531 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
3532 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
3533 | ||
3534 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
3535 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
3536 | ||
c8d77183 SR |
3537 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
3538 | ||
3539 | kfree(s); | |
3540 | ||
3541 | return count; | |
3542 | } | |
3543 | ||
3544 | static const struct file_operations tracing_stats_fops = { | |
3545 | .open = tracing_open_generic, | |
3546 | .read = tracing_stats_read, | |
3547 | }; | |
3548 | ||
bc0c38d1 SR |
3549 | #ifdef CONFIG_DYNAMIC_FTRACE |
3550 | ||
b807c3d0 SR |
3551 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3552 | { | |
3553 | return 0; | |
3554 | } | |
3555 | ||
bc0c38d1 | 3556 | static ssize_t |
b807c3d0 | 3557 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3558 | size_t cnt, loff_t *ppos) |
3559 | { | |
a26a2a27 SR |
3560 | static char ftrace_dyn_info_buffer[1024]; |
3561 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3562 | unsigned long *p = filp->private_data; |
b807c3d0 | 3563 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3564 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3565 | int r; |
3566 | ||
b807c3d0 SR |
3567 | mutex_lock(&dyn_info_mutex); |
3568 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3569 | |
a26a2a27 | 3570 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3571 | buf[r++] = '\n'; |
3572 | ||
3573 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3574 | ||
3575 | mutex_unlock(&dyn_info_mutex); | |
3576 | ||
3577 | return r; | |
bc0c38d1 SR |
3578 | } |
3579 | ||
5e2336a0 | 3580 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3581 | .open = tracing_open_generic, |
b807c3d0 | 3582 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3583 | }; |
3584 | #endif | |
3585 | ||
3586 | static struct dentry *d_tracer; | |
3587 | ||
3588 | struct dentry *tracing_init_dentry(void) | |
3589 | { | |
3590 | static int once; | |
3591 | ||
3592 | if (d_tracer) | |
3593 | return d_tracer; | |
3594 | ||
3e1f60b8 FW |
3595 | if (!debugfs_initialized()) |
3596 | return NULL; | |
3597 | ||
bc0c38d1 SR |
3598 | d_tracer = debugfs_create_dir("tracing", NULL); |
3599 | ||
3600 | if (!d_tracer && !once) { | |
3601 | once = 1; | |
3602 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3603 | return NULL; | |
3604 | } | |
3605 | ||
3606 | return d_tracer; | |
3607 | } | |
3608 | ||
b04cc6b1 FW |
3609 | static struct dentry *d_percpu; |
3610 | ||
3611 | struct dentry *tracing_dentry_percpu(void) | |
3612 | { | |
3613 | static int once; | |
3614 | struct dentry *d_tracer; | |
3615 | ||
3616 | if (d_percpu) | |
3617 | return d_percpu; | |
3618 | ||
3619 | d_tracer = tracing_init_dentry(); | |
3620 | ||
3621 | if (!d_tracer) | |
3622 | return NULL; | |
3623 | ||
3624 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
3625 | ||
3626 | if (!d_percpu && !once) { | |
3627 | once = 1; | |
3628 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
3629 | return NULL; | |
3630 | } | |
3631 | ||
3632 | return d_percpu; | |
3633 | } | |
3634 | ||
3635 | static void tracing_init_debugfs_percpu(long cpu) | |
3636 | { | |
3637 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 3638 | struct dentry *d_cpu; |
8656e7a2 FW |
3639 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ |
3640 | char cpu_dir[7]; | |
b04cc6b1 FW |
3641 | |
3642 | if (cpu > 999 || cpu < 0) | |
3643 | return; | |
3644 | ||
8656e7a2 FW |
3645 | sprintf(cpu_dir, "cpu%ld", cpu); |
3646 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
3647 | if (!d_cpu) { | |
3648 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
3649 | return; | |
3650 | } | |
b04cc6b1 | 3651 | |
8656e7a2 | 3652 | /* per cpu trace_pipe */ |
5452af66 FW |
3653 | trace_create_file("trace_pipe", 0444, d_cpu, |
3654 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
3655 | |
3656 | /* per cpu trace */ | |
5452af66 FW |
3657 | trace_create_file("trace", 0644, d_cpu, |
3658 | (void *) cpu, &tracing_fops); | |
7f96f93f | 3659 | |
5452af66 FW |
3660 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
3661 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 3662 | |
c8d77183 SR |
3663 | trace_create_file("stats", 0444, d_cpu, |
3664 | (void *) cpu, &tracing_stats_fops); | |
b04cc6b1 FW |
3665 | } |
3666 | ||
60a11774 SR |
3667 | #ifdef CONFIG_FTRACE_SELFTEST |
3668 | /* Let selftest have access to static functions in this file */ | |
3669 | #include "trace_selftest.c" | |
3670 | #endif | |
3671 | ||
577b785f SR |
3672 | struct trace_option_dentry { |
3673 | struct tracer_opt *opt; | |
3674 | struct tracer_flags *flags; | |
3675 | struct dentry *entry; | |
3676 | }; | |
3677 | ||
3678 | static ssize_t | |
3679 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3680 | loff_t *ppos) | |
3681 | { | |
3682 | struct trace_option_dentry *topt = filp->private_data; | |
3683 | char *buf; | |
3684 | ||
3685 | if (topt->flags->val & topt->opt->bit) | |
3686 | buf = "1\n"; | |
3687 | else | |
3688 | buf = "0\n"; | |
3689 | ||
3690 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3691 | } | |
3692 | ||
3693 | static ssize_t | |
3694 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3695 | loff_t *ppos) | |
3696 | { | |
3697 | struct trace_option_dentry *topt = filp->private_data; | |
3698 | unsigned long val; | |
3699 | char buf[64]; | |
3700 | int ret; | |
3701 | ||
3702 | if (cnt >= sizeof(buf)) | |
3703 | return -EINVAL; | |
3704 | ||
3705 | if (copy_from_user(&buf, ubuf, cnt)) | |
3706 | return -EFAULT; | |
3707 | ||
3708 | buf[cnt] = 0; | |
3709 | ||
3710 | ret = strict_strtoul(buf, 10, &val); | |
3711 | if (ret < 0) | |
3712 | return ret; | |
3713 | ||
3714 | ret = 0; | |
3715 | switch (val) { | |
3716 | case 0: | |
3717 | /* do nothing if already cleared */ | |
3718 | if (!(topt->flags->val & topt->opt->bit)) | |
3719 | break; | |
3720 | ||
3721 | mutex_lock(&trace_types_lock); | |
3722 | if (current_trace->set_flag) | |
3723 | ret = current_trace->set_flag(topt->flags->val, | |
3724 | topt->opt->bit, 0); | |
3725 | mutex_unlock(&trace_types_lock); | |
3726 | if (ret) | |
3727 | return ret; | |
3728 | topt->flags->val &= ~topt->opt->bit; | |
3729 | break; | |
3730 | case 1: | |
3731 | /* do nothing if already set */ | |
3732 | if (topt->flags->val & topt->opt->bit) | |
3733 | break; | |
3734 | ||
3735 | mutex_lock(&trace_types_lock); | |
3736 | if (current_trace->set_flag) | |
3737 | ret = current_trace->set_flag(topt->flags->val, | |
3738 | topt->opt->bit, 1); | |
3739 | mutex_unlock(&trace_types_lock); | |
3740 | if (ret) | |
3741 | return ret; | |
3742 | topt->flags->val |= topt->opt->bit; | |
3743 | break; | |
3744 | ||
3745 | default: | |
3746 | return -EINVAL; | |
3747 | } | |
3748 | ||
3749 | *ppos += cnt; | |
3750 | ||
3751 | return cnt; | |
3752 | } | |
3753 | ||
3754 | ||
3755 | static const struct file_operations trace_options_fops = { | |
3756 | .open = tracing_open_generic, | |
3757 | .read = trace_options_read, | |
3758 | .write = trace_options_write, | |
3759 | }; | |
3760 | ||
a8259075 SR |
3761 | static ssize_t |
3762 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3763 | loff_t *ppos) | |
3764 | { | |
3765 | long index = (long)filp->private_data; | |
3766 | char *buf; | |
3767 | ||
3768 | if (trace_flags & (1 << index)) | |
3769 | buf = "1\n"; | |
3770 | else | |
3771 | buf = "0\n"; | |
3772 | ||
3773 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3774 | } | |
3775 | ||
3776 | static ssize_t | |
3777 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3778 | loff_t *ppos) | |
3779 | { | |
3780 | long index = (long)filp->private_data; | |
3781 | char buf[64]; | |
3782 | unsigned long val; | |
3783 | int ret; | |
3784 | ||
3785 | if (cnt >= sizeof(buf)) | |
3786 | return -EINVAL; | |
3787 | ||
3788 | if (copy_from_user(&buf, ubuf, cnt)) | |
3789 | return -EFAULT; | |
3790 | ||
3791 | buf[cnt] = 0; | |
3792 | ||
3793 | ret = strict_strtoul(buf, 10, &val); | |
3794 | if (ret < 0) | |
3795 | return ret; | |
3796 | ||
3797 | switch (val) { | |
3798 | case 0: | |
3799 | trace_flags &= ~(1 << index); | |
3800 | break; | |
3801 | case 1: | |
3802 | trace_flags |= 1 << index; | |
3803 | break; | |
3804 | ||
3805 | default: | |
3806 | return -EINVAL; | |
3807 | } | |
3808 | ||
3809 | *ppos += cnt; | |
3810 | ||
3811 | return cnt; | |
3812 | } | |
3813 | ||
a8259075 SR |
3814 | static const struct file_operations trace_options_core_fops = { |
3815 | .open = tracing_open_generic, | |
3816 | .read = trace_options_core_read, | |
3817 | .write = trace_options_core_write, | |
3818 | }; | |
3819 | ||
5452af66 FW |
3820 | struct dentry *trace_create_file(const char *name, |
3821 | mode_t mode, | |
3822 | struct dentry *parent, | |
3823 | void *data, | |
3824 | const struct file_operations *fops) | |
3825 | { | |
3826 | struct dentry *ret; | |
3827 | ||
3828 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
3829 | if (!ret) | |
3830 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
3831 | ||
3832 | return ret; | |
3833 | } | |
3834 | ||
3835 | ||
a8259075 SR |
3836 | static struct dentry *trace_options_init_dentry(void) |
3837 | { | |
3838 | struct dentry *d_tracer; | |
3839 | static struct dentry *t_options; | |
3840 | ||
3841 | if (t_options) | |
3842 | return t_options; | |
3843 | ||
3844 | d_tracer = tracing_init_dentry(); | |
3845 | if (!d_tracer) | |
3846 | return NULL; | |
3847 | ||
3848 | t_options = debugfs_create_dir("options", d_tracer); | |
3849 | if (!t_options) { | |
3850 | pr_warning("Could not create debugfs directory 'options'\n"); | |
3851 | return NULL; | |
3852 | } | |
3853 | ||
3854 | return t_options; | |
3855 | } | |
3856 | ||
577b785f SR |
3857 | static void |
3858 | create_trace_option_file(struct trace_option_dentry *topt, | |
3859 | struct tracer_flags *flags, | |
3860 | struct tracer_opt *opt) | |
3861 | { | |
3862 | struct dentry *t_options; | |
577b785f SR |
3863 | |
3864 | t_options = trace_options_init_dentry(); | |
3865 | if (!t_options) | |
3866 | return; | |
3867 | ||
3868 | topt->flags = flags; | |
3869 | topt->opt = opt; | |
3870 | ||
5452af66 | 3871 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
3872 | &trace_options_fops); |
3873 | ||
577b785f SR |
3874 | } |
3875 | ||
3876 | static struct trace_option_dentry * | |
3877 | create_trace_option_files(struct tracer *tracer) | |
3878 | { | |
3879 | struct trace_option_dentry *topts; | |
3880 | struct tracer_flags *flags; | |
3881 | struct tracer_opt *opts; | |
3882 | int cnt; | |
3883 | ||
3884 | if (!tracer) | |
3885 | return NULL; | |
3886 | ||
3887 | flags = tracer->flags; | |
3888 | ||
3889 | if (!flags || !flags->opts) | |
3890 | return NULL; | |
3891 | ||
3892 | opts = flags->opts; | |
3893 | ||
3894 | for (cnt = 0; opts[cnt].name; cnt++) | |
3895 | ; | |
3896 | ||
0cfe8245 | 3897 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
3898 | if (!topts) |
3899 | return NULL; | |
3900 | ||
3901 | for (cnt = 0; opts[cnt].name; cnt++) | |
3902 | create_trace_option_file(&topts[cnt], flags, | |
3903 | &opts[cnt]); | |
3904 | ||
3905 | return topts; | |
3906 | } | |
3907 | ||
3908 | static void | |
3909 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
3910 | { | |
3911 | int cnt; | |
3912 | ||
3913 | if (!topts) | |
3914 | return; | |
3915 | ||
3916 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
3917 | if (topts[cnt].entry) | |
3918 | debugfs_remove(topts[cnt].entry); | |
3919 | } | |
3920 | ||
3921 | kfree(topts); | |
3922 | } | |
3923 | ||
a8259075 SR |
3924 | static struct dentry * |
3925 | create_trace_option_core_file(const char *option, long index) | |
3926 | { | |
3927 | struct dentry *t_options; | |
a8259075 SR |
3928 | |
3929 | t_options = trace_options_init_dentry(); | |
3930 | if (!t_options) | |
3931 | return NULL; | |
3932 | ||
5452af66 | 3933 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 3934 | &trace_options_core_fops); |
a8259075 SR |
3935 | } |
3936 | ||
3937 | static __init void create_trace_options_dir(void) | |
3938 | { | |
3939 | struct dentry *t_options; | |
a8259075 SR |
3940 | int i; |
3941 | ||
3942 | t_options = trace_options_init_dentry(); | |
3943 | if (!t_options) | |
3944 | return; | |
3945 | ||
5452af66 FW |
3946 | for (i = 0; trace_options[i]; i++) |
3947 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
3948 | } |
3949 | ||
b5ad384e | 3950 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
3951 | { |
3952 | struct dentry *d_tracer; | |
b04cc6b1 | 3953 | int cpu; |
bc0c38d1 SR |
3954 | |
3955 | d_tracer = tracing_init_dentry(); | |
3956 | ||
5452af66 FW |
3957 | trace_create_file("tracing_enabled", 0644, d_tracer, |
3958 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 3959 | |
5452af66 FW |
3960 | trace_create_file("trace_options", 0644, d_tracer, |
3961 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 3962 | |
5452af66 FW |
3963 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
3964 | NULL, &tracing_cpumask_fops); | |
3965 | ||
3966 | trace_create_file("trace", 0644, d_tracer, | |
3967 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 3968 | |
5452af66 FW |
3969 | trace_create_file("available_tracers", 0444, d_tracer, |
3970 | &global_trace, &show_traces_fops); | |
3971 | ||
339ae5d3 | 3972 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
3973 | &global_trace, &set_tracer_fops); |
3974 | ||
5d4a9dba | 3975 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
3976 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
3977 | &tracing_max_latency, &tracing_max_lat_fops); | |
3978 | ||
3979 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
3980 | &tracing_thresh, &tracing_max_lat_fops); | |
5d4a9dba | 3981 | #endif |
a8259075 | 3982 | |
339ae5d3 | 3983 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
3984 | NULL, &tracing_readme_fops); |
3985 | ||
3986 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 3987 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
3988 | |
3989 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
3990 | &global_trace, &tracing_entries_fops); | |
3991 | ||
3992 | trace_create_file("trace_marker", 0220, d_tracer, | |
3993 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 3994 | |
69abe6a5 AP |
3995 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
3996 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 3997 | |
5079f326 Z |
3998 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
3999 | &trace_clock_fops); | |
4000 | ||
bc0c38d1 | 4001 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4002 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4003 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4004 | #endif |
d618b3e6 IM |
4005 | #ifdef CONFIG_SYSPROF_TRACER |
4006 | init_tracer_sysprof_debugfs(d_tracer); | |
4007 | #endif | |
b04cc6b1 | 4008 | |
5452af66 FW |
4009 | create_trace_options_dir(); |
4010 | ||
b04cc6b1 FW |
4011 | for_each_tracing_cpu(cpu) |
4012 | tracing_init_debugfs_percpu(cpu); | |
4013 | ||
b5ad384e | 4014 | return 0; |
bc0c38d1 SR |
4015 | } |
4016 | ||
3f5a54e3 SR |
4017 | static int trace_panic_handler(struct notifier_block *this, |
4018 | unsigned long event, void *unused) | |
4019 | { | |
944ac425 SR |
4020 | if (ftrace_dump_on_oops) |
4021 | ftrace_dump(); | |
3f5a54e3 SR |
4022 | return NOTIFY_OK; |
4023 | } | |
4024 | ||
4025 | static struct notifier_block trace_panic_notifier = { | |
4026 | .notifier_call = trace_panic_handler, | |
4027 | .next = NULL, | |
4028 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4029 | }; | |
4030 | ||
4031 | static int trace_die_handler(struct notifier_block *self, | |
4032 | unsigned long val, | |
4033 | void *data) | |
4034 | { | |
4035 | switch (val) { | |
4036 | case DIE_OOPS: | |
944ac425 SR |
4037 | if (ftrace_dump_on_oops) |
4038 | ftrace_dump(); | |
3f5a54e3 SR |
4039 | break; |
4040 | default: | |
4041 | break; | |
4042 | } | |
4043 | return NOTIFY_OK; | |
4044 | } | |
4045 | ||
4046 | static struct notifier_block trace_die_notifier = { | |
4047 | .notifier_call = trace_die_handler, | |
4048 | .priority = 200 | |
4049 | }; | |
4050 | ||
4051 | /* | |
4052 | * printk is set to max of 1024, we really don't need it that big. | |
4053 | * Nothing should be printing 1000 characters anyway. | |
4054 | */ | |
4055 | #define TRACE_MAX_PRINT 1000 | |
4056 | ||
4057 | /* | |
4058 | * Define here KERN_TRACE so that we have one place to modify | |
4059 | * it if we decide to change what log level the ftrace dump | |
4060 | * should be at. | |
4061 | */ | |
428aee14 | 4062 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
4063 | |
4064 | static void | |
4065 | trace_printk_seq(struct trace_seq *s) | |
4066 | { | |
4067 | /* Probably should print a warning here. */ | |
4068 | if (s->len >= 1000) | |
4069 | s->len = 1000; | |
4070 | ||
4071 | /* should be zero ended, but we are paranoid. */ | |
4072 | s->buffer[s->len] = 0; | |
4073 | ||
4074 | printk(KERN_TRACE "%s", s->buffer); | |
4075 | ||
f9520750 | 4076 | trace_seq_init(s); |
3f5a54e3 SR |
4077 | } |
4078 | ||
cf586b61 | 4079 | static void __ftrace_dump(bool disable_tracing) |
3f5a54e3 | 4080 | { |
cd891ae0 SR |
4081 | static raw_spinlock_t ftrace_dump_lock = |
4082 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
3f5a54e3 SR |
4083 | /* use static because iter can be a bit big for the stack */ |
4084 | static struct trace_iterator iter; | |
cf586b61 | 4085 | unsigned int old_userobj; |
3f5a54e3 | 4086 | static int dump_ran; |
d769041f SR |
4087 | unsigned long flags; |
4088 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4089 | |
4090 | /* only one dump */ | |
cd891ae0 SR |
4091 | local_irq_save(flags); |
4092 | __raw_spin_lock(&ftrace_dump_lock); | |
3f5a54e3 SR |
4093 | if (dump_ran) |
4094 | goto out; | |
4095 | ||
4096 | dump_ran = 1; | |
4097 | ||
0ee6b6cf | 4098 | tracing_off(); |
cf586b61 FW |
4099 | |
4100 | if (disable_tracing) | |
4101 | ftrace_kill(); | |
3f5a54e3 | 4102 | |
d769041f SR |
4103 | for_each_tracing_cpu(cpu) { |
4104 | atomic_inc(&global_trace.data[cpu]->disabled); | |
4105 | } | |
4106 | ||
cf586b61 FW |
4107 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4108 | ||
b54d3de9 TE |
4109 | /* don't look at user memory in panic mode */ |
4110 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4111 | ||
3f5a54e3 SR |
4112 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
4113 | ||
e543ad76 | 4114 | /* Simulate the iterator */ |
3f5a54e3 SR |
4115 | iter.tr = &global_trace; |
4116 | iter.trace = current_trace; | |
e543ad76 | 4117 | iter.cpu_file = TRACE_PIPE_ALL_CPU; |
3f5a54e3 SR |
4118 | |
4119 | /* | |
4120 | * We need to stop all tracing on all CPUS to read the | |
4121 | * the next buffer. This is a bit expensive, but is | |
4122 | * not done often. We fill all what we can read, | |
4123 | * and then release the locks again. | |
4124 | */ | |
4125 | ||
3f5a54e3 SR |
4126 | while (!trace_empty(&iter)) { |
4127 | ||
4128 | if (!cnt) | |
4129 | printk(KERN_TRACE "---------------------------------\n"); | |
4130 | ||
4131 | cnt++; | |
4132 | ||
4133 | /* reset all but tr, trace, and overruns */ | |
4134 | memset(&iter.seq, 0, | |
4135 | sizeof(struct trace_iterator) - | |
4136 | offsetof(struct trace_iterator, seq)); | |
4137 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4138 | iter.pos = -1; | |
4139 | ||
4140 | if (find_next_entry_inc(&iter) != NULL) { | |
74e7ff8c LJ |
4141 | int ret; |
4142 | ||
4143 | ret = print_trace_line(&iter); | |
4144 | if (ret != TRACE_TYPE_NO_CONSUME) | |
4145 | trace_consume(&iter); | |
3f5a54e3 SR |
4146 | } |
4147 | ||
4148 | trace_printk_seq(&iter.seq); | |
4149 | } | |
4150 | ||
4151 | if (!cnt) | |
4152 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4153 | else | |
4154 | printk(KERN_TRACE "---------------------------------\n"); | |
4155 | ||
cf586b61 FW |
4156 | /* Re-enable tracing if requested */ |
4157 | if (!disable_tracing) { | |
4158 | trace_flags |= old_userobj; | |
4159 | ||
4160 | for_each_tracing_cpu(cpu) { | |
4161 | atomic_dec(&global_trace.data[cpu]->disabled); | |
4162 | } | |
4163 | tracing_on(); | |
4164 | } | |
4165 | ||
3f5a54e3 | 4166 | out: |
cd891ae0 SR |
4167 | __raw_spin_unlock(&ftrace_dump_lock); |
4168 | local_irq_restore(flags); | |
3f5a54e3 SR |
4169 | } |
4170 | ||
cf586b61 FW |
4171 | /* By default: disable tracing after the dump */ |
4172 | void ftrace_dump(void) | |
4173 | { | |
4174 | __ftrace_dump(true); | |
4175 | } | |
4176 | ||
3928a8a2 | 4177 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4178 | { |
73c5162a | 4179 | int ring_buf_size; |
4c11d7ae | 4180 | int i; |
9e01c1b7 | 4181 | int ret = -ENOMEM; |
4c11d7ae | 4182 | |
9e01c1b7 RR |
4183 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4184 | goto out; | |
4185 | ||
4186 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4187 | goto out_free_buffer_mask; | |
4c11d7ae | 4188 | |
b04cc6b1 FW |
4189 | if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) |
4190 | goto out_free_tracing_cpumask; | |
4191 | ||
73c5162a SR |
4192 | /* To save memory, keep the ring buffer size to its minimum */ |
4193 | if (ring_buffer_expanded) | |
4194 | ring_buf_size = trace_buf_size; | |
4195 | else | |
4196 | ring_buf_size = 1; | |
4197 | ||
9e01c1b7 RR |
4198 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4199 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
b04cc6b1 | 4200 | cpumask_clear(tracing_reader_cpumask); |
9e01c1b7 RR |
4201 | |
4202 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
73c5162a | 4203 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4204 | TRACE_BUFFER_FLAGS); |
4205 | if (!global_trace.buffer) { | |
4206 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4207 | WARN_ON(1); | |
9e01c1b7 | 4208 | goto out_free_cpumask; |
4c11d7ae | 4209 | } |
3928a8a2 | 4210 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4211 | |
9e01c1b7 | 4212 | |
4c11d7ae | 4213 | #ifdef CONFIG_TRACER_MAX_TRACE |
73c5162a | 4214 | max_tr.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4215 | TRACE_BUFFER_FLAGS); |
4216 | if (!max_tr.buffer) { | |
4217 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4218 | WARN_ON(1); | |
4219 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4220 | goto out_free_cpumask; |
4c11d7ae | 4221 | } |
3928a8a2 SR |
4222 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
4223 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 4224 | #endif |
ab46428c | 4225 | |
4c11d7ae | 4226 | /* Allocate the first page for all buffers */ |
ab46428c | 4227 | for_each_tracing_cpu(i) { |
566b0aaf | 4228 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 | 4229 | max_tr.data[i] = &per_cpu(max_data, i); |
4c11d7ae | 4230 | } |
bc0c38d1 | 4231 | |
bc0c38d1 SR |
4232 | trace_init_cmdlines(); |
4233 | ||
43a15386 | 4234 | register_tracer(&nop_trace); |
79fb0768 | 4235 | current_trace = &nop_trace; |
b5ad384e FW |
4236 | #ifdef CONFIG_BOOT_TRACER |
4237 | register_tracer(&boot_tracer); | |
b5ad384e | 4238 | #endif |
60a11774 SR |
4239 | /* All seems OK, enable tracing */ |
4240 | tracing_disabled = 0; | |
3928a8a2 | 4241 | |
3f5a54e3 SR |
4242 | atomic_notifier_chain_register(&panic_notifier_list, |
4243 | &trace_panic_notifier); | |
4244 | ||
4245 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4246 | |
4247 | return 0; | |
3f5a54e3 | 4248 | |
9e01c1b7 | 4249 | out_free_cpumask: |
b04cc6b1 FW |
4250 | free_cpumask_var(tracing_reader_cpumask); |
4251 | out_free_tracing_cpumask: | |
9e01c1b7 RR |
4252 | free_cpumask_var(tracing_cpumask); |
4253 | out_free_buffer_mask: | |
4254 | free_cpumask_var(tracing_buffer_mask); | |
4255 | out: | |
4256 | return ret; | |
bc0c38d1 | 4257 | } |
b2821ae6 SR |
4258 | |
4259 | __init static int clear_boot_tracer(void) | |
4260 | { | |
4261 | /* | |
4262 | * The default tracer at boot buffer is an init section. | |
4263 | * This function is called in lateinit. If we did not | |
4264 | * find the boot tracer, then clear it out, to prevent | |
4265 | * later registration from accessing the buffer that is | |
4266 | * about to be freed. | |
4267 | */ | |
4268 | if (!default_bootup_tracer) | |
4269 | return 0; | |
4270 | ||
4271 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4272 | default_bootup_tracer); | |
4273 | default_bootup_tracer = NULL; | |
4274 | ||
4275 | return 0; | |
4276 | } | |
4277 | ||
b5ad384e FW |
4278 | early_initcall(tracer_alloc_buffers); |
4279 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4280 | late_initcall(clear_boot_tracer); |