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