Commit | Line | Data |
---|---|---|
bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
bc0c38d1 | 15 | #include <linux/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
4c11d7ae | 23 | #include <linux/pagemap.h> |
bc0c38d1 SR |
24 | #include <linux/hardirq.h> |
25 | #include <linux/linkage.h> | |
26 | #include <linux/uaccess.h> | |
2cadf913 | 27 | #include <linux/kprobes.h> |
bc0c38d1 SR |
28 | #include <linux/ftrace.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/percpu.h> | |
2cadf913 | 31 | #include <linux/splice.h> |
3f5a54e3 | 32 | #include <linux/kdebug.h> |
5f0c6c03 | 33 | #include <linux/string.h> |
bc0c38d1 SR |
34 | #include <linux/ctype.h> |
35 | #include <linux/init.h> | |
2a2cc8f7 | 36 | #include <linux/poll.h> |
bc0c38d1 SR |
37 | #include <linux/gfp.h> |
38 | #include <linux/fs.h> | |
86387f7e | 39 | |
bc0c38d1 | 40 | #include "trace.h" |
f0868d1e | 41 | #include "trace_output.h" |
bc0c38d1 | 42 | |
3928a8a2 SR |
43 | #define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE) |
44 | ||
745b1626 | 45 | unsigned long __read_mostly tracing_max_latency; |
bc0c38d1 SR |
46 | unsigned long __read_mostly tracing_thresh; |
47 | ||
73c5162a SR |
48 | /* |
49 | * On boot up, the ring buffer is set to the minimum size, so that | |
50 | * we do not waste memory on systems that are not using tracing. | |
51 | */ | |
52 | static int ring_buffer_expanded; | |
53 | ||
8e1b82e0 FW |
54 | /* |
55 | * We need to change this state when a selftest is running. | |
ff32504f FW |
56 | * A selftest will lurk into the ring-buffer to count the |
57 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 58 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
59 | * at the same time, giving false positive or negative results. |
60 | */ | |
8e1b82e0 | 61 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 62 | |
b2821ae6 SR |
63 | /* |
64 | * If a tracer is running, we do not want to run SELFTEST. | |
65 | */ | |
66 | static bool __read_mostly tracing_selftest_disabled; | |
67 | ||
adf9f195 FW |
68 | /* For tracers that don't implement custom flags */ |
69 | static struct tracer_opt dummy_tracer_opt[] = { | |
70 | { } | |
71 | }; | |
72 | ||
73 | static struct tracer_flags dummy_tracer_flags = { | |
74 | .val = 0, | |
75 | .opts = dummy_tracer_opt | |
76 | }; | |
77 | ||
78 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
79 | { | |
80 | return 0; | |
81 | } | |
0f048701 SR |
82 | |
83 | /* | |
84 | * Kill all tracing for good (never come back). | |
85 | * It is initialized to 1 but will turn to zero if the initialization | |
86 | * of the tracer is successful. But that is the only place that sets | |
87 | * this back to zero. | |
88 | */ | |
4fd27358 | 89 | static int tracing_disabled = 1; |
0f048701 | 90 | |
d769041f SR |
91 | static DEFINE_PER_CPU(local_t, ftrace_cpu_disabled); |
92 | ||
93 | static inline void ftrace_disable_cpu(void) | |
94 | { | |
95 | preempt_disable(); | |
96 | local_inc(&__get_cpu_var(ftrace_cpu_disabled)); | |
97 | } | |
98 | ||
99 | static inline void ftrace_enable_cpu(void) | |
100 | { | |
101 | local_dec(&__get_cpu_var(ftrace_cpu_disabled)); | |
102 | preempt_enable(); | |
103 | } | |
104 | ||
9e01c1b7 | 105 | static cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 106 | |
b04cc6b1 FW |
107 | /* Define which cpu buffers are currently read in trace_pipe */ |
108 | static cpumask_var_t tracing_reader_cpumask; | |
109 | ||
ab46428c | 110 | #define for_each_tracing_cpu(cpu) \ |
9e01c1b7 | 111 | for_each_cpu(cpu, tracing_buffer_mask) |
ab46428c | 112 | |
944ac425 SR |
113 | /* |
114 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
115 | * | |
116 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
117 | * is set, then ftrace_dump is called. This will output the contents | |
118 | * of the ftrace buffers to the console. This is very useful for | |
119 | * capturing traces that lead to crashes and outputing it to a | |
120 | * serial console. | |
121 | * | |
122 | * It is default off, but you can enable it with either specifying | |
123 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
124 | * /proc/sys/kernel/ftrace_dump_on_oops to true. | |
125 | */ | |
126 | int ftrace_dump_on_oops; | |
127 | ||
b2821ae6 SR |
128 | static int tracing_set_tracer(const char *buf); |
129 | ||
130 | #define BOOTUP_TRACER_SIZE 100 | |
131 | static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata; | |
132 | static char *default_bootup_tracer; | |
d9e54076 PZ |
133 | |
134 | static int __init set_ftrace(char *str) | |
135 | { | |
b2821ae6 SR |
136 | strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); |
137 | default_bootup_tracer = bootup_tracer_buf; | |
73c5162a SR |
138 | /* We are using ftrace early, expand it */ |
139 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
140 | return 1; |
141 | } | |
b2821ae6 | 142 | __setup("ftrace=", set_ftrace); |
d9e54076 | 143 | |
944ac425 SR |
144 | static int __init set_ftrace_dump_on_oops(char *str) |
145 | { | |
146 | ftrace_dump_on_oops = 1; | |
147 | return 1; | |
148 | } | |
149 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 150 | |
cf8e3474 | 151 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
152 | { |
153 | nsec += 500; | |
154 | do_div(nsec, 1000); | |
155 | return nsec; | |
156 | } | |
157 | ||
4fcdae83 SR |
158 | /* |
159 | * The global_trace is the descriptor that holds the tracing | |
160 | * buffers for the live tracing. For each CPU, it contains | |
161 | * a link list of pages that will store trace entries. The | |
162 | * page descriptor of the pages in the memory is used to hold | |
163 | * the link list by linking the lru item in the page descriptor | |
164 | * to each of the pages in the buffer per CPU. | |
165 | * | |
166 | * For each active CPU there is a data field that holds the | |
167 | * pages for the buffer for that CPU. Each CPU has the same number | |
168 | * of pages allocated for its buffer. | |
169 | */ | |
bc0c38d1 SR |
170 | static struct trace_array global_trace; |
171 | ||
172 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
173 | ||
eb02ce01 TZ |
174 | int filter_current_check_discard(struct ftrace_event_call *call, void *rec, |
175 | struct ring_buffer_event *event) | |
176 | { | |
177 | return filter_check_discard(call, rec, global_trace.buffer, event); | |
178 | } | |
17c873ec | 179 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 180 | |
37886f6a SR |
181 | cycle_t ftrace_now(int cpu) |
182 | { | |
183 | u64 ts; | |
184 | ||
185 | /* Early boot up does not have a buffer yet */ | |
186 | if (!global_trace.buffer) | |
187 | return trace_clock_local(); | |
188 | ||
189 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
190 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
191 | ||
192 | return ts; | |
193 | } | |
bc0c38d1 | 194 | |
4fcdae83 SR |
195 | /* |
196 | * The max_tr is used to snapshot the global_trace when a maximum | |
197 | * latency is reached. Some tracers will use this to store a maximum | |
198 | * trace while it continues examining live traces. | |
199 | * | |
200 | * The buffers for the max_tr are set up the same as the global_trace. | |
201 | * When a snapshot is taken, the link list of the max_tr is swapped | |
202 | * with the link list of the global_trace and the buffers are reset for | |
203 | * the global_trace so the tracing can continue. | |
204 | */ | |
bc0c38d1 SR |
205 | static struct trace_array max_tr; |
206 | ||
207 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
208 | ||
4fcdae83 | 209 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 210 | static int tracer_enabled = 1; |
4fcdae83 | 211 | |
9036990d SR |
212 | /** |
213 | * tracing_is_enabled - return tracer_enabled status | |
214 | * | |
215 | * This function is used by other tracers to know the status | |
216 | * of the tracer_enabled flag. Tracers may use this function | |
217 | * to know if it should enable their features when starting | |
218 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
219 | */ | |
220 | int tracing_is_enabled(void) | |
221 | { | |
222 | return tracer_enabled; | |
223 | } | |
224 | ||
4fcdae83 | 225 | /* |
3928a8a2 SR |
226 | * trace_buf_size is the size in bytes that is allocated |
227 | * for a buffer. Note, the number of bytes is always rounded | |
228 | * to page size. | |
3f5a54e3 SR |
229 | * |
230 | * This number is purposely set to a low number of 16384. | |
231 | * If the dump on oops happens, it will be much appreciated | |
232 | * to not have to wait for all that output. Anyway this can be | |
233 | * boot time and run time configurable. | |
4fcdae83 | 234 | */ |
3928a8a2 | 235 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 236 | |
3928a8a2 | 237 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 238 | |
4fcdae83 | 239 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 240 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
241 | |
242 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 243 | static struct tracer *current_trace __read_mostly; |
4fcdae83 SR |
244 | |
245 | /* | |
246 | * max_tracer_type_len is used to simplify the allocating of | |
247 | * buffers to read userspace tracer names. We keep track of | |
248 | * the longest tracer name registered. | |
249 | */ | |
bc0c38d1 SR |
250 | static int max_tracer_type_len; |
251 | ||
4fcdae83 SR |
252 | /* |
253 | * trace_types_lock is used to protect the trace_types list. | |
254 | * This lock is also used to keep user access serialized. | |
255 | * Accesses from userspace will grab this lock while userspace | |
256 | * activities happen inside the kernel. | |
257 | */ | |
bc0c38d1 | 258 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
259 | |
260 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
261 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
262 | ||
ee6bce52 | 263 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 264 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a SR |
265 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
266 | TRACE_ITER_GRAPH_TIME; | |
4e655519 | 267 | |
4fcdae83 SR |
268 | /** |
269 | * trace_wake_up - wake up tasks waiting for trace input | |
270 | * | |
271 | * Simply wakes up any task that is blocked on the trace_wait | |
272 | * queue. These is used with trace_poll for tasks polling the trace. | |
273 | */ | |
4e655519 IM |
274 | void trace_wake_up(void) |
275 | { | |
017730c1 IM |
276 | /* |
277 | * The runqueue_is_locked() can fail, but this is the best we | |
278 | * have for now: | |
279 | */ | |
280 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
281 | wake_up(&trace_wait); |
282 | } | |
bc0c38d1 | 283 | |
3928a8a2 | 284 | static int __init set_buf_size(char *str) |
bc0c38d1 | 285 | { |
3928a8a2 | 286 | unsigned long buf_size; |
c6caeeb1 SR |
287 | int ret; |
288 | ||
bc0c38d1 SR |
289 | if (!str) |
290 | return 0; | |
3928a8a2 | 291 | ret = strict_strtoul(str, 0, &buf_size); |
c6caeeb1 | 292 | /* nr_entries can not be zero */ |
3928a8a2 | 293 | if (ret < 0 || 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", |
af4617bd | 326 | "global-clock", |
be6f164a | 327 | "sleep-time", |
a2a16d6a | 328 | "graph-time", |
bc0c38d1 SR |
329 | NULL |
330 | }; | |
331 | ||
4fcdae83 SR |
332 | /* |
333 | * ftrace_max_lock is used to protect the swapping of buffers | |
334 | * when taking a max snapshot. The buffers themselves are | |
335 | * protected by per_cpu spinlocks. But the action of the swap | |
336 | * needs its own lock. | |
337 | * | |
338 | * This is defined as a raw_spinlock_t in order to help | |
339 | * with performance when lockdep debugging is enabled. | |
340 | */ | |
92205c23 SR |
341 | static raw_spinlock_t ftrace_max_lock = |
342 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
bc0c38d1 SR |
343 | |
344 | /* | |
345 | * Copy the new maximum trace into the separate maximum-trace | |
346 | * structure. (this way the maximum trace is permanently saved, | |
347 | * for later retrieval via /debugfs/tracing/latency_trace) | |
348 | */ | |
e309b41d | 349 | static void |
bc0c38d1 SR |
350 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
351 | { | |
352 | struct trace_array_cpu *data = tr->data[cpu]; | |
353 | ||
354 | max_tr.cpu = cpu; | |
355 | max_tr.time_start = data->preempt_timestamp; | |
356 | ||
357 | data = max_tr.data[cpu]; | |
358 | data->saved_latency = tracing_max_latency; | |
359 | ||
360 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
361 | data->pid = tsk->pid; | |
b6dff3ec | 362 | data->uid = task_uid(tsk); |
bc0c38d1 SR |
363 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
364 | data->policy = tsk->policy; | |
365 | data->rt_priority = tsk->rt_priority; | |
366 | ||
367 | /* record this tasks comm */ | |
af513098 | 368 | tracing_record_cmdline(tsk); |
bc0c38d1 SR |
369 | } |
370 | ||
6c6c2796 PP |
371 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
372 | { | |
373 | int len; | |
374 | int ret; | |
375 | ||
2dc5d12b SR |
376 | if (!cnt) |
377 | return 0; | |
378 | ||
6c6c2796 PP |
379 | if (s->len <= s->readpos) |
380 | return -EBUSY; | |
381 | ||
382 | len = s->len - s->readpos; | |
383 | if (cnt > len) | |
384 | cnt = len; | |
385 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 386 | if (ret == cnt) |
6c6c2796 PP |
387 | return -EFAULT; |
388 | ||
2dc5d12b SR |
389 | cnt -= ret; |
390 | ||
e74da523 | 391 | s->readpos += cnt; |
6c6c2796 | 392 | return cnt; |
214023c3 SR |
393 | } |
394 | ||
b8b94265 | 395 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
396 | { |
397 | int len; | |
398 | void *ret; | |
399 | ||
400 | if (s->len <= s->readpos) | |
401 | return -EBUSY; | |
402 | ||
403 | len = s->len - s->readpos; | |
404 | if (cnt > len) | |
405 | cnt = len; | |
406 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
407 | if (!ret) | |
408 | return -EFAULT; | |
409 | ||
e74da523 | 410 | s->readpos += cnt; |
3c56819b EGM |
411 | return cnt; |
412 | } | |
413 | ||
4fcdae83 SR |
414 | /** |
415 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
416 | * @tr: tracer | |
417 | * @tsk: the task with the latency | |
418 | * @cpu: The cpu that initiated the trace. | |
419 | * | |
420 | * Flip the buffers between the @tr and the max_tr and record information | |
421 | * about which task was the cause of this latency. | |
422 | */ | |
e309b41d | 423 | void |
bc0c38d1 SR |
424 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
425 | { | |
3928a8a2 | 426 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 427 | |
4c11d7ae | 428 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 429 | __raw_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
430 | |
431 | tr->buffer = max_tr.buffer; | |
432 | max_tr.buffer = buf; | |
433 | ||
d769041f | 434 | ftrace_disable_cpu(); |
3928a8a2 | 435 | ring_buffer_reset(tr->buffer); |
d769041f | 436 | ftrace_enable_cpu(); |
bc0c38d1 SR |
437 | |
438 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 439 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
440 | } |
441 | ||
442 | /** | |
443 | * update_max_tr_single - only copy one trace over, and reset the rest | |
444 | * @tr - tracer | |
445 | * @tsk - task with the latency | |
446 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
447 | * |
448 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 449 | */ |
e309b41d | 450 | void |
bc0c38d1 SR |
451 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
452 | { | |
3928a8a2 | 453 | int ret; |
bc0c38d1 | 454 | |
4c11d7ae | 455 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 456 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 457 | |
d769041f SR |
458 | ftrace_disable_cpu(); |
459 | ||
3928a8a2 SR |
460 | ring_buffer_reset(max_tr.buffer); |
461 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); | |
462 | ||
d769041f SR |
463 | ftrace_enable_cpu(); |
464 | ||
97b17efe | 465 | WARN_ON_ONCE(ret && ret != -EAGAIN); |
bc0c38d1 SR |
466 | |
467 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 468 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
469 | } |
470 | ||
4fcdae83 SR |
471 | /** |
472 | * register_tracer - register a tracer with the ftrace system. | |
473 | * @type - the plugin for the tracer | |
474 | * | |
475 | * Register a new plugin tracer. | |
476 | */ | |
bc0c38d1 | 477 | int register_tracer(struct tracer *type) |
e7669b8e HE |
478 | __releases(kernel_lock) |
479 | __acquires(kernel_lock) | |
bc0c38d1 SR |
480 | { |
481 | struct tracer *t; | |
482 | int len; | |
483 | int ret = 0; | |
484 | ||
485 | if (!type->name) { | |
486 | pr_info("Tracer must have a name\n"); | |
487 | return -1; | |
488 | } | |
489 | ||
86fa2f60 IM |
490 | /* |
491 | * When this gets called we hold the BKL which means that | |
492 | * preemption is disabled. Various trace selftests however | |
493 | * need to disable and enable preemption for successful tests. | |
494 | * So we drop the BKL here and grab it after the tests again. | |
495 | */ | |
496 | unlock_kernel(); | |
bc0c38d1 | 497 | mutex_lock(&trace_types_lock); |
86fa2f60 | 498 | |
8e1b82e0 FW |
499 | tracing_selftest_running = true; |
500 | ||
bc0c38d1 SR |
501 | for (t = trace_types; t; t = t->next) { |
502 | if (strcmp(type->name, t->name) == 0) { | |
503 | /* already found */ | |
504 | pr_info("Trace %s already registered\n", | |
505 | type->name); | |
506 | ret = -1; | |
507 | goto out; | |
508 | } | |
509 | } | |
510 | ||
adf9f195 FW |
511 | if (!type->set_flag) |
512 | type->set_flag = &dummy_set_flag; | |
513 | if (!type->flags) | |
514 | type->flags = &dummy_tracer_flags; | |
515 | else | |
516 | if (!type->flags->opts) | |
517 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
518 | if (!type->wait_pipe) |
519 | type->wait_pipe = default_wait_pipe; | |
520 | ||
adf9f195 | 521 | |
60a11774 | 522 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 523 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 524 | struct tracer *saved_tracer = current_trace; |
60a11774 | 525 | struct trace_array *tr = &global_trace; |
60a11774 | 526 | int i; |
ff32504f | 527 | |
60a11774 SR |
528 | /* |
529 | * Run a selftest on this tracer. | |
530 | * Here we reset the trace buffer, and set the current | |
531 | * tracer to be this tracer. The tracer can then run some | |
532 | * internal tracing to verify that everything is in order. | |
533 | * If we fail, we do not register this tracer. | |
534 | */ | |
86fa2f60 | 535 | for_each_tracing_cpu(i) |
3928a8a2 | 536 | tracing_reset(tr, i); |
86fa2f60 | 537 | |
60a11774 | 538 | current_trace = type; |
60a11774 SR |
539 | /* the test is responsible for initializing and enabling */ |
540 | pr_info("Testing tracer %s: ", type->name); | |
541 | ret = type->selftest(type, tr); | |
542 | /* the test is responsible for resetting too */ | |
543 | current_trace = saved_tracer; | |
60a11774 SR |
544 | if (ret) { |
545 | printk(KERN_CONT "FAILED!\n"); | |
546 | goto out; | |
547 | } | |
1d4db00a | 548 | /* Only reset on passing, to avoid touching corrupted buffers */ |
86fa2f60 | 549 | for_each_tracing_cpu(i) |
3928a8a2 | 550 | tracing_reset(tr, i); |
86fa2f60 | 551 | |
60a11774 SR |
552 | printk(KERN_CONT "PASSED\n"); |
553 | } | |
554 | #endif | |
555 | ||
bc0c38d1 SR |
556 | type->next = trace_types; |
557 | trace_types = type; | |
558 | len = strlen(type->name); | |
559 | if (len > max_tracer_type_len) | |
560 | max_tracer_type_len = len; | |
60a11774 | 561 | |
bc0c38d1 | 562 | out: |
8e1b82e0 | 563 | tracing_selftest_running = false; |
bc0c38d1 SR |
564 | mutex_unlock(&trace_types_lock); |
565 | ||
dac74940 SR |
566 | if (ret || !default_bootup_tracer) |
567 | goto out_unlock; | |
568 | ||
569 | if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE)) | |
570 | goto out_unlock; | |
571 | ||
572 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
573 | /* Do we want this tracer to start on bootup? */ | |
574 | tracing_set_tracer(type->name); | |
575 | default_bootup_tracer = NULL; | |
576 | /* disable other selftests, since this will break it. */ | |
577 | tracing_selftest_disabled = 1; | |
b2821ae6 | 578 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
579 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
580 | type->name); | |
b2821ae6 | 581 | #endif |
b2821ae6 | 582 | |
dac74940 | 583 | out_unlock: |
b2821ae6 | 584 | lock_kernel(); |
bc0c38d1 SR |
585 | return ret; |
586 | } | |
587 | ||
588 | void unregister_tracer(struct tracer *type) | |
589 | { | |
590 | struct tracer **t; | |
591 | int len; | |
592 | ||
593 | mutex_lock(&trace_types_lock); | |
594 | for (t = &trace_types; *t; t = &(*t)->next) { | |
595 | if (*t == type) | |
596 | goto found; | |
597 | } | |
598 | pr_info("Trace %s not registered\n", type->name); | |
599 | goto out; | |
600 | ||
601 | found: | |
602 | *t = (*t)->next; | |
b5db03c4 ACM |
603 | |
604 | if (type == current_trace && tracer_enabled) { | |
605 | tracer_enabled = 0; | |
606 | tracing_stop(); | |
607 | if (current_trace->stop) | |
608 | current_trace->stop(&global_trace); | |
609 | current_trace = &nop_trace; | |
610 | } | |
611 | ||
bc0c38d1 SR |
612 | if (strlen(type->name) != max_tracer_type_len) |
613 | goto out; | |
614 | ||
615 | max_tracer_type_len = 0; | |
616 | for (t = &trace_types; *t; t = &(*t)->next) { | |
617 | len = strlen((*t)->name); | |
618 | if (len > max_tracer_type_len) | |
619 | max_tracer_type_len = len; | |
620 | } | |
621 | out: | |
622 | mutex_unlock(&trace_types_lock); | |
623 | } | |
624 | ||
3928a8a2 | 625 | void tracing_reset(struct trace_array *tr, int cpu) |
bc0c38d1 | 626 | { |
d769041f | 627 | ftrace_disable_cpu(); |
3928a8a2 | 628 | ring_buffer_reset_cpu(tr->buffer, cpu); |
d769041f | 629 | ftrace_enable_cpu(); |
bc0c38d1 SR |
630 | } |
631 | ||
213cc060 PE |
632 | void tracing_reset_online_cpus(struct trace_array *tr) |
633 | { | |
634 | int cpu; | |
635 | ||
636 | tr->time_start = ftrace_now(tr->cpu); | |
637 | ||
638 | for_each_online_cpu(cpu) | |
639 | tracing_reset(tr, cpu); | |
640 | } | |
641 | ||
bc0c38d1 | 642 | #define SAVED_CMDLINES 128 |
2c7eea4c | 643 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
644 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
645 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
646 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
647 | static int cmdline_idx; | |
efed792d | 648 | static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; |
25b0b44a | 649 | |
25b0b44a | 650 | /* temporary disable recording */ |
4fd27358 | 651 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
652 | |
653 | static void trace_init_cmdlines(void) | |
654 | { | |
2c7eea4c TG |
655 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
656 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
657 | cmdline_idx = 0; |
658 | } | |
659 | ||
0f048701 SR |
660 | static int trace_stop_count; |
661 | static DEFINE_SPINLOCK(tracing_start_lock); | |
662 | ||
69bb54ec SR |
663 | /** |
664 | * ftrace_off_permanent - disable all ftrace code permanently | |
665 | * | |
666 | * This should only be called when a serious anomally has | |
667 | * been detected. This will turn off the function tracing, | |
668 | * ring buffers, and other tracing utilites. It takes no | |
669 | * locks and can be called from any context. | |
670 | */ | |
671 | void ftrace_off_permanent(void) | |
672 | { | |
673 | tracing_disabled = 1; | |
674 | ftrace_stop(); | |
675 | tracing_off_permanent(); | |
676 | } | |
677 | ||
0f048701 SR |
678 | /** |
679 | * tracing_start - quick start of the tracer | |
680 | * | |
681 | * If tracing is enabled but was stopped by tracing_stop, | |
682 | * this will start the tracer back up. | |
683 | */ | |
684 | void tracing_start(void) | |
685 | { | |
686 | struct ring_buffer *buffer; | |
687 | unsigned long flags; | |
688 | ||
689 | if (tracing_disabled) | |
690 | return; | |
691 | ||
692 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
693 | if (--trace_stop_count) { |
694 | if (trace_stop_count < 0) { | |
695 | /* Someone screwed up their debugging */ | |
696 | WARN_ON_ONCE(1); | |
697 | trace_stop_count = 0; | |
698 | } | |
0f048701 SR |
699 | goto out; |
700 | } | |
701 | ||
702 | ||
703 | buffer = global_trace.buffer; | |
704 | if (buffer) | |
705 | ring_buffer_record_enable(buffer); | |
706 | ||
707 | buffer = max_tr.buffer; | |
708 | if (buffer) | |
709 | ring_buffer_record_enable(buffer); | |
710 | ||
711 | ftrace_start(); | |
712 | out: | |
713 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
714 | } | |
715 | ||
716 | /** | |
717 | * tracing_stop - quick stop of the tracer | |
718 | * | |
719 | * Light weight way to stop tracing. Use in conjunction with | |
720 | * tracing_start. | |
721 | */ | |
722 | void tracing_stop(void) | |
723 | { | |
724 | struct ring_buffer *buffer; | |
725 | unsigned long flags; | |
726 | ||
727 | ftrace_stop(); | |
728 | spin_lock_irqsave(&tracing_start_lock, flags); | |
729 | if (trace_stop_count++) | |
730 | goto out; | |
731 | ||
732 | buffer = global_trace.buffer; | |
733 | if (buffer) | |
734 | ring_buffer_record_disable(buffer); | |
735 | ||
736 | buffer = max_tr.buffer; | |
737 | if (buffer) | |
738 | ring_buffer_record_disable(buffer); | |
739 | ||
740 | out: | |
741 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
742 | } | |
743 | ||
e309b41d | 744 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 745 | |
e309b41d | 746 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 747 | { |
a635cf04 | 748 | unsigned pid, idx; |
bc0c38d1 SR |
749 | |
750 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
751 | return; | |
752 | ||
753 | /* | |
754 | * It's not the end of the world if we don't get | |
755 | * the lock, but we also don't want to spin | |
756 | * nor do we want to disable interrupts, | |
757 | * so if we miss here, then better luck next time. | |
758 | */ | |
efed792d | 759 | if (!__raw_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
760 | return; |
761 | ||
762 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 763 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
764 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
765 | ||
a635cf04 CE |
766 | /* |
767 | * Check whether the cmdline buffer at idx has a pid | |
768 | * mapped. We are going to overwrite that entry so we | |
769 | * need to clear the map_pid_to_cmdline. Otherwise we | |
770 | * would read the new comm for the old pid. | |
771 | */ | |
772 | pid = map_cmdline_to_pid[idx]; | |
773 | if (pid != NO_CMDLINE_MAP) | |
774 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 775 | |
a635cf04 | 776 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
777 | map_pid_to_cmdline[tsk->pid] = idx; |
778 | ||
779 | cmdline_idx = idx; | |
780 | } | |
781 | ||
782 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
783 | ||
efed792d | 784 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
785 | } |
786 | ||
4ca53085 | 787 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 788 | { |
bc0c38d1 SR |
789 | unsigned map; |
790 | ||
4ca53085 SR |
791 | if (!pid) { |
792 | strcpy(comm, "<idle>"); | |
793 | return; | |
794 | } | |
bc0c38d1 | 795 | |
4ca53085 SR |
796 | if (pid > PID_MAX_DEFAULT) { |
797 | strcpy(comm, "<...>"); | |
798 | return; | |
799 | } | |
bc0c38d1 | 800 | |
4ca53085 | 801 | __raw_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 802 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
803 | if (map != NO_CMDLINE_MAP) |
804 | strcpy(comm, saved_cmdlines[map]); | |
805 | else | |
806 | strcpy(comm, "<...>"); | |
bc0c38d1 | 807 | |
4ca53085 | 808 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
809 | } |
810 | ||
e309b41d | 811 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 812 | { |
18aecd36 TG |
813 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
814 | !tracing_is_on()) | |
bc0c38d1 SR |
815 | return; |
816 | ||
817 | trace_save_cmdline(tsk); | |
818 | } | |
819 | ||
45dcd8b8 | 820 | void |
38697053 SR |
821 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
822 | int pc) | |
bc0c38d1 SR |
823 | { |
824 | struct task_struct *tsk = current; | |
bc0c38d1 | 825 | |
777e208d SR |
826 | entry->preempt_count = pc & 0xff; |
827 | entry->pid = (tsk) ? tsk->pid : 0; | |
ef18012b | 828 | entry->tgid = (tsk) ? tsk->tgid : 0; |
777e208d | 829 | entry->flags = |
9244489a | 830 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 831 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
832 | #else |
833 | TRACE_FLAG_IRQS_NOSUPPORT | | |
834 | #endif | |
bc0c38d1 SR |
835 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
836 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
837 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
838 | } | |
839 | ||
51a763dd ACM |
840 | struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr, |
841 | unsigned char type, | |
842 | unsigned long len, | |
843 | unsigned long flags, int pc) | |
844 | { | |
845 | struct ring_buffer_event *event; | |
846 | ||
847 | event = ring_buffer_lock_reserve(tr->buffer, len); | |
848 | if (event != NULL) { | |
849 | struct trace_entry *ent = ring_buffer_event_data(event); | |
850 | ||
851 | tracing_generic_entry_update(ent, flags, pc); | |
852 | ent->type = type; | |
853 | } | |
854 | ||
855 | return event; | |
856 | } | |
857 | static void ftrace_trace_stack(struct trace_array *tr, | |
858 | unsigned long flags, int skip, int pc); | |
859 | static void ftrace_trace_userstack(struct trace_array *tr, | |
860 | unsigned long flags, int pc); | |
861 | ||
07edf712 FW |
862 | static inline void __trace_buffer_unlock_commit(struct trace_array *tr, |
863 | struct ring_buffer_event *event, | |
864 | unsigned long flags, int pc, | |
865 | int wake) | |
51a763dd ACM |
866 | { |
867 | ring_buffer_unlock_commit(tr->buffer, event); | |
868 | ||
869 | ftrace_trace_stack(tr, flags, 6, pc); | |
870 | ftrace_trace_userstack(tr, flags, pc); | |
07edf712 FW |
871 | |
872 | if (wake) | |
873 | trace_wake_up(); | |
874 | } | |
875 | ||
876 | void trace_buffer_unlock_commit(struct trace_array *tr, | |
877 | struct ring_buffer_event *event, | |
878 | unsigned long flags, int pc) | |
879 | { | |
880 | __trace_buffer_unlock_commit(tr, event, flags, pc, 1); | |
51a763dd ACM |
881 | } |
882 | ||
ef5580d0 SR |
883 | struct ring_buffer_event * |
884 | trace_current_buffer_lock_reserve(unsigned char type, unsigned long len, | |
885 | unsigned long flags, int pc) | |
886 | { | |
887 | return trace_buffer_lock_reserve(&global_trace, | |
888 | type, len, flags, pc); | |
889 | } | |
17c873ec | 890 | EXPORT_SYMBOL(trace_current_buffer_lock_reserve); |
ef5580d0 SR |
891 | |
892 | void trace_current_buffer_unlock_commit(struct ring_buffer_event *event, | |
893 | unsigned long flags, int pc) | |
894 | { | |
77d9f465 | 895 | __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 1); |
07edf712 FW |
896 | } |
897 | ||
898 | void trace_nowake_buffer_unlock_commit(struct ring_buffer_event *event, | |
899 | unsigned long flags, int pc) | |
900 | { | |
77d9f465 SR |
901 | __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 0); |
902 | } | |
903 | ||
904 | void trace_current_buffer_discard_commit(struct ring_buffer_event *event) | |
905 | { | |
906 | ring_buffer_discard_commit(global_trace.buffer, event); | |
ef5580d0 | 907 | } |
17c873ec | 908 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
ef5580d0 | 909 | |
e309b41d | 910 | void |
7be42151 | 911 | trace_function(struct trace_array *tr, |
38697053 SR |
912 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
913 | int pc) | |
bc0c38d1 | 914 | { |
e1112b4d | 915 | struct ftrace_event_call *call = &event_function; |
3928a8a2 | 916 | struct ring_buffer_event *event; |
777e208d | 917 | struct ftrace_entry *entry; |
bc0c38d1 | 918 | |
d769041f SR |
919 | /* If we are reading the ring buffer, don't trace */ |
920 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
921 | return; | |
922 | ||
51a763dd ACM |
923 | event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry), |
924 | flags, pc); | |
3928a8a2 SR |
925 | if (!event) |
926 | return; | |
927 | entry = ring_buffer_event_data(event); | |
777e208d SR |
928 | entry->ip = ip; |
929 | entry->parent_ip = parent_ip; | |
e1112b4d | 930 | |
eb02ce01 TZ |
931 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
932 | ring_buffer_unlock_commit(tr->buffer, event); | |
bc0c38d1 SR |
933 | } |
934 | ||
fb52607a | 935 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
16185369 | 936 | static int __trace_graph_entry(struct trace_array *tr, |
287b6e68 FW |
937 | struct ftrace_graph_ent *trace, |
938 | unsigned long flags, | |
939 | int pc) | |
940 | { | |
e1112b4d | 941 | struct ftrace_event_call *call = &event_funcgraph_entry; |
287b6e68 FW |
942 | struct ring_buffer_event *event; |
943 | struct ftrace_graph_ent_entry *entry; | |
287b6e68 FW |
944 | |
945 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
16185369 | 946 | return 0; |
287b6e68 | 947 | |
51a763dd ACM |
948 | event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_ENT, |
949 | sizeof(*entry), flags, pc); | |
287b6e68 | 950 | if (!event) |
16185369 | 951 | return 0; |
287b6e68 | 952 | entry = ring_buffer_event_data(event); |
287b6e68 | 953 | entry->graph_ent = *trace; |
eb02ce01 TZ |
954 | if (!filter_current_check_discard(call, entry, event)) |
955 | ring_buffer_unlock_commit(global_trace.buffer, event); | |
16185369 FW |
956 | |
957 | return 1; | |
287b6e68 FW |
958 | } |
959 | ||
960 | static void __trace_graph_return(struct trace_array *tr, | |
fb52607a | 961 | struct ftrace_graph_ret *trace, |
15e6cb36 FW |
962 | unsigned long flags, |
963 | int pc) | |
964 | { | |
e1112b4d | 965 | struct ftrace_event_call *call = &event_funcgraph_exit; |
15e6cb36 | 966 | struct ring_buffer_event *event; |
287b6e68 | 967 | struct ftrace_graph_ret_entry *entry; |
15e6cb36 FW |
968 | |
969 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
970 | return; | |
971 | ||
51a763dd ACM |
972 | event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_RET, |
973 | sizeof(*entry), flags, pc); | |
15e6cb36 FW |
974 | if (!event) |
975 | return; | |
976 | entry = ring_buffer_event_data(event); | |
287b6e68 | 977 | entry->ret = *trace; |
eb02ce01 TZ |
978 | if (!filter_current_check_discard(call, entry, event)) |
979 | ring_buffer_unlock_commit(global_trace.buffer, event); | |
15e6cb36 FW |
980 | } |
981 | #endif | |
982 | ||
e309b41d | 983 | void |
2e0f5761 | 984 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
985 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
986 | int pc) | |
2e0f5761 IM |
987 | { |
988 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 989 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
990 | } |
991 | ||
53614991 | 992 | static void __ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
993 | unsigned long flags, |
994 | int skip, int pc) | |
86387f7e | 995 | { |
c2c80529 | 996 | #ifdef CONFIG_STACKTRACE |
e1112b4d | 997 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 998 | struct ring_buffer_event *event; |
777e208d | 999 | struct stack_entry *entry; |
86387f7e IM |
1000 | struct stack_trace trace; |
1001 | ||
51a763dd ACM |
1002 | event = trace_buffer_lock_reserve(tr, TRACE_STACK, |
1003 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1004 | if (!event) |
1005 | return; | |
1006 | entry = ring_buffer_event_data(event); | |
777e208d | 1007 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
1008 | |
1009 | trace.nr_entries = 0; | |
1010 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1011 | trace.skip = skip; | |
777e208d | 1012 | trace.entries = entry->caller; |
86387f7e IM |
1013 | |
1014 | save_stack_trace(&trace); | |
eb02ce01 TZ |
1015 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1016 | ring_buffer_unlock_commit(tr->buffer, event); | |
c2c80529 | 1017 | #endif |
f0a920d5 IM |
1018 | } |
1019 | ||
53614991 | 1020 | static void ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
1021 | unsigned long flags, |
1022 | int skip, int pc) | |
1023 | { | |
1024 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1025 | return; | |
1026 | ||
7be42151 | 1027 | __ftrace_trace_stack(tr, flags, skip, pc); |
53614991 SR |
1028 | } |
1029 | ||
38697053 | 1030 | void __trace_stack(struct trace_array *tr, |
38697053 | 1031 | unsigned long flags, |
53614991 | 1032 | int skip, int pc) |
38697053 | 1033 | { |
7be42151 | 1034 | __ftrace_trace_stack(tr, flags, skip, pc); |
38697053 SR |
1035 | } |
1036 | ||
02b67518 | 1037 | static void ftrace_trace_userstack(struct trace_array *tr, |
7be42151 | 1038 | unsigned long flags, int pc) |
02b67518 | 1039 | { |
c7425acb | 1040 | #ifdef CONFIG_STACKTRACE |
e1112b4d | 1041 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1042 | struct ring_buffer_event *event; |
02b67518 TE |
1043 | struct userstack_entry *entry; |
1044 | struct stack_trace trace; | |
02b67518 TE |
1045 | |
1046 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1047 | return; | |
1048 | ||
51a763dd ACM |
1049 | event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK, |
1050 | sizeof(*entry), flags, pc); | |
02b67518 TE |
1051 | if (!event) |
1052 | return; | |
1053 | entry = ring_buffer_event_data(event); | |
02b67518 TE |
1054 | |
1055 | memset(&entry->caller, 0, sizeof(entry->caller)); | |
1056 | ||
1057 | trace.nr_entries = 0; | |
1058 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1059 | trace.skip = 0; | |
1060 | trace.entries = entry->caller; | |
1061 | ||
1062 | save_stack_trace_user(&trace); | |
eb02ce01 TZ |
1063 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1064 | ring_buffer_unlock_commit(tr->buffer, event); | |
c7425acb | 1065 | #endif |
02b67518 TE |
1066 | } |
1067 | ||
4fd27358 HE |
1068 | #ifdef UNUSED |
1069 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1070 | { |
7be42151 | 1071 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1072 | } |
4fd27358 | 1073 | #endif /* UNUSED */ |
02b67518 | 1074 | |
38697053 | 1075 | static void |
7be42151 | 1076 | ftrace_trace_special(void *__tr, |
38697053 SR |
1077 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1078 | int pc) | |
a4feb834 | 1079 | { |
3928a8a2 | 1080 | struct ring_buffer_event *event; |
a4feb834 | 1081 | struct trace_array *tr = __tr; |
777e208d | 1082 | struct special_entry *entry; |
a4feb834 | 1083 | |
51a763dd ACM |
1084 | event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL, |
1085 | sizeof(*entry), 0, pc); | |
3928a8a2 SR |
1086 | if (!event) |
1087 | return; | |
1088 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1089 | entry->arg1 = arg1; |
1090 | entry->arg2 = arg2; | |
1091 | entry->arg3 = arg3; | |
51a763dd | 1092 | trace_buffer_unlock_commit(tr, event, 0, pc); |
a4feb834 IM |
1093 | } |
1094 | ||
38697053 SR |
1095 | void |
1096 | __trace_special(void *__tr, void *__data, | |
1097 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1098 | { | |
7be42151 | 1099 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1100 | } |
1101 | ||
e309b41d | 1102 | void |
bc0c38d1 | 1103 | tracing_sched_switch_trace(struct trace_array *tr, |
86387f7e IM |
1104 | struct task_struct *prev, |
1105 | struct task_struct *next, | |
38697053 | 1106 | unsigned long flags, int pc) |
bc0c38d1 | 1107 | { |
e1112b4d | 1108 | struct ftrace_event_call *call = &event_context_switch; |
3928a8a2 | 1109 | struct ring_buffer_event *event; |
777e208d | 1110 | struct ctx_switch_entry *entry; |
bc0c38d1 | 1111 | |
51a763dd ACM |
1112 | event = trace_buffer_lock_reserve(tr, TRACE_CTX, |
1113 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1114 | if (!event) |
1115 | return; | |
1116 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1117 | entry->prev_pid = prev->pid; |
1118 | entry->prev_prio = prev->prio; | |
1119 | entry->prev_state = prev->state; | |
1120 | entry->next_pid = next->pid; | |
1121 | entry->next_prio = next->prio; | |
1122 | entry->next_state = next->state; | |
1123 | entry->next_cpu = task_cpu(next); | |
e1112b4d | 1124 | |
eb02ce01 TZ |
1125 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1126 | trace_buffer_unlock_commit(tr, event, flags, pc); | |
bc0c38d1 SR |
1127 | } |
1128 | ||
57422797 IM |
1129 | void |
1130 | tracing_sched_wakeup_trace(struct trace_array *tr, | |
86387f7e IM |
1131 | struct task_struct *wakee, |
1132 | struct task_struct *curr, | |
38697053 | 1133 | unsigned long flags, int pc) |
57422797 | 1134 | { |
e1112b4d | 1135 | struct ftrace_event_call *call = &event_wakeup; |
3928a8a2 | 1136 | struct ring_buffer_event *event; |
777e208d | 1137 | struct ctx_switch_entry *entry; |
57422797 | 1138 | |
51a763dd ACM |
1139 | event = trace_buffer_lock_reserve(tr, TRACE_WAKE, |
1140 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1141 | if (!event) |
1142 | return; | |
1143 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1144 | entry->prev_pid = curr->pid; |
1145 | entry->prev_prio = curr->prio; | |
1146 | entry->prev_state = curr->state; | |
1147 | entry->next_pid = wakee->pid; | |
1148 | entry->next_prio = wakee->prio; | |
1149 | entry->next_state = wakee->state; | |
1150 | entry->next_cpu = task_cpu(wakee); | |
6eaaa5d5 | 1151 | |
eb02ce01 TZ |
1152 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1153 | ring_buffer_unlock_commit(tr->buffer, event); | |
6eaaa5d5 FW |
1154 | ftrace_trace_stack(tr, flags, 6, pc); |
1155 | ftrace_trace_userstack(tr, flags, pc); | |
57422797 IM |
1156 | } |
1157 | ||
4902f884 SR |
1158 | void |
1159 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1160 | { | |
1161 | struct trace_array *tr = &global_trace; | |
1162 | struct trace_array_cpu *data; | |
5aa1ba6a | 1163 | unsigned long flags; |
4902f884 | 1164 | int cpu; |
38697053 | 1165 | int pc; |
4902f884 | 1166 | |
c76f0694 | 1167 | if (tracing_disabled) |
4902f884 SR |
1168 | return; |
1169 | ||
38697053 | 1170 | pc = preempt_count(); |
5aa1ba6a | 1171 | local_irq_save(flags); |
4902f884 SR |
1172 | cpu = raw_smp_processor_id(); |
1173 | data = tr->data[cpu]; | |
4902f884 | 1174 | |
5aa1ba6a | 1175 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1176 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1177 | |
5aa1ba6a SR |
1178 | atomic_dec(&data->disabled); |
1179 | local_irq_restore(flags); | |
4902f884 SR |
1180 | } |
1181 | ||
fb52607a | 1182 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e49dc19c | 1183 | int trace_graph_entry(struct ftrace_graph_ent *trace) |
15e6cb36 FW |
1184 | { |
1185 | struct trace_array *tr = &global_trace; | |
1186 | struct trace_array_cpu *data; | |
1187 | unsigned long flags; | |
1188 | long disabled; | |
16185369 | 1189 | int ret; |
15e6cb36 FW |
1190 | int cpu; |
1191 | int pc; | |
1192 | ||
804a6851 SR |
1193 | if (!ftrace_trace_task(current)) |
1194 | return 0; | |
1195 | ||
ea4e2bc4 SR |
1196 | if (!ftrace_graph_addr(trace->func)) |
1197 | return 0; | |
1198 | ||
a5e25883 | 1199 | local_irq_save(flags); |
15e6cb36 FW |
1200 | cpu = raw_smp_processor_id(); |
1201 | data = tr->data[cpu]; | |
1202 | disabled = atomic_inc_return(&data->disabled); | |
1203 | if (likely(disabled == 1)) { | |
1204 | pc = preempt_count(); | |
16185369 FW |
1205 | ret = __trace_graph_entry(tr, trace, flags, pc); |
1206 | } else { | |
1207 | ret = 0; | |
287b6e68 | 1208 | } |
ea4e2bc4 SR |
1209 | /* Only do the atomic if it is not already set */ |
1210 | if (!test_tsk_trace_graph(current)) | |
1211 | set_tsk_trace_graph(current); | |
16185369 | 1212 | |
287b6e68 | 1213 | atomic_dec(&data->disabled); |
a5e25883 | 1214 | local_irq_restore(flags); |
e49dc19c | 1215 | |
16185369 | 1216 | return ret; |
287b6e68 FW |
1217 | } |
1218 | ||
1219 | void trace_graph_return(struct ftrace_graph_ret *trace) | |
1220 | { | |
1221 | struct trace_array *tr = &global_trace; | |
1222 | struct trace_array_cpu *data; | |
1223 | unsigned long flags; | |
1224 | long disabled; | |
1225 | int cpu; | |
1226 | int pc; | |
1227 | ||
a5e25883 | 1228 | local_irq_save(flags); |
287b6e68 FW |
1229 | cpu = raw_smp_processor_id(); |
1230 | data = tr->data[cpu]; | |
1231 | disabled = atomic_inc_return(&data->disabled); | |
1232 | if (likely(disabled == 1)) { | |
1233 | pc = preempt_count(); | |
7be42151 | 1234 | __trace_graph_return(tr, trace, flags, pc); |
15e6cb36 | 1235 | } |
ea4e2bc4 SR |
1236 | if (!trace->depth) |
1237 | clear_tsk_trace_graph(current); | |
15e6cb36 | 1238 | atomic_dec(&data->disabled); |
a5e25883 | 1239 | local_irq_restore(flags); |
15e6cb36 | 1240 | } |
fb52607a | 1241 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
15e6cb36 | 1242 | |
769b0441 FW |
1243 | |
1244 | /** | |
48ead020 | 1245 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1246 | * |
1247 | */ | |
40ce74f1 | 1248 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1249 | { |
80370cb7 SR |
1250 | static raw_spinlock_t trace_buf_lock = |
1251 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
769b0441 FW |
1252 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1253 | ||
e1112b4d | 1254 | struct ftrace_event_call *call = &event_bprint; |
769b0441 FW |
1255 | struct ring_buffer_event *event; |
1256 | struct trace_array *tr = &global_trace; | |
1257 | struct trace_array_cpu *data; | |
48ead020 | 1258 | struct bprint_entry *entry; |
769b0441 FW |
1259 | unsigned long flags; |
1260 | int resched; | |
1261 | int cpu, len = 0, size, pc; | |
1262 | ||
1263 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1264 | return 0; | |
1265 | ||
1266 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1267 | pause_graph_tracing(); | |
1268 | ||
1269 | pc = preempt_count(); | |
1270 | resched = ftrace_preempt_disable(); | |
1271 | cpu = raw_smp_processor_id(); | |
1272 | data = tr->data[cpu]; | |
1273 | ||
1274 | if (unlikely(atomic_read(&data->disabled))) | |
1275 | goto out; | |
1276 | ||
80370cb7 SR |
1277 | /* Lockdep uses trace_printk for lock tracing */ |
1278 | local_irq_save(flags); | |
1279 | __raw_spin_lock(&trace_buf_lock); | |
769b0441 FW |
1280 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1281 | ||
1282 | if (len > TRACE_BUF_SIZE || len < 0) | |
1283 | goto out_unlock; | |
1284 | ||
1285 | size = sizeof(*entry) + sizeof(u32) * len; | |
48ead020 | 1286 | event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc); |
769b0441 FW |
1287 | if (!event) |
1288 | goto out_unlock; | |
1289 | entry = ring_buffer_event_data(event); | |
1290 | entry->ip = ip; | |
769b0441 FW |
1291 | entry->fmt = fmt; |
1292 | ||
1293 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
eb02ce01 TZ |
1294 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1295 | ring_buffer_unlock_commit(tr->buffer, event); | |
769b0441 FW |
1296 | |
1297 | out_unlock: | |
80370cb7 SR |
1298 | __raw_spin_unlock(&trace_buf_lock); |
1299 | local_irq_restore(flags); | |
769b0441 FW |
1300 | |
1301 | out: | |
1302 | ftrace_preempt_enable(resched); | |
1303 | unpause_graph_tracing(); | |
1304 | ||
1305 | return len; | |
1306 | } | |
48ead020 FW |
1307 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1308 | ||
40ce74f1 | 1309 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
48ead020 FW |
1310 | { |
1311 | static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; | |
1312 | static char trace_buf[TRACE_BUF_SIZE]; | |
1313 | ||
e1112b4d | 1314 | struct ftrace_event_call *call = &event_print; |
48ead020 FW |
1315 | struct ring_buffer_event *event; |
1316 | struct trace_array *tr = &global_trace; | |
1317 | struct trace_array_cpu *data; | |
1318 | int cpu, len = 0, size, pc; | |
1319 | struct print_entry *entry; | |
1320 | unsigned long irq_flags; | |
1321 | ||
1322 | if (tracing_disabled || tracing_selftest_running) | |
1323 | return 0; | |
1324 | ||
1325 | pc = preempt_count(); | |
1326 | preempt_disable_notrace(); | |
1327 | cpu = raw_smp_processor_id(); | |
1328 | data = tr->data[cpu]; | |
1329 | ||
1330 | if (unlikely(atomic_read(&data->disabled))) | |
1331 | goto out; | |
1332 | ||
1333 | pause_graph_tracing(); | |
1334 | raw_local_irq_save(irq_flags); | |
1335 | __raw_spin_lock(&trace_buf_lock); | |
1336 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); | |
1337 | ||
1338 | len = min(len, TRACE_BUF_SIZE-1); | |
1339 | trace_buf[len] = 0; | |
1340 | ||
1341 | size = sizeof(*entry) + len + 1; | |
1342 | event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc); | |
1343 | if (!event) | |
1344 | goto out_unlock; | |
1345 | entry = ring_buffer_event_data(event); | |
1346 | entry->ip = ip; | |
48ead020 FW |
1347 | |
1348 | memcpy(&entry->buf, trace_buf, len); | |
1349 | entry->buf[len] = 0; | |
eb02ce01 TZ |
1350 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1351 | ring_buffer_unlock_commit(tr->buffer, event); | |
48ead020 FW |
1352 | |
1353 | out_unlock: | |
1354 | __raw_spin_unlock(&trace_buf_lock); | |
1355 | raw_local_irq_restore(irq_flags); | |
1356 | unpause_graph_tracing(); | |
1357 | out: | |
1358 | preempt_enable_notrace(); | |
1359 | ||
1360 | return len; | |
1361 | } | |
769b0441 FW |
1362 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1363 | ||
bc0c38d1 SR |
1364 | enum trace_file_type { |
1365 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1366 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1367 | }; |
1368 | ||
e2ac8ef5 | 1369 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1370 | { |
d769041f SR |
1371 | /* Don't allow ftrace to trace into the ring buffers */ |
1372 | ftrace_disable_cpu(); | |
1373 | ||
5a90f577 | 1374 | iter->idx++; |
d769041f SR |
1375 | if (iter->buffer_iter[iter->cpu]) |
1376 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1377 | ||
1378 | ftrace_enable_cpu(); | |
5a90f577 SR |
1379 | } |
1380 | ||
e309b41d | 1381 | static struct trace_entry * |
3928a8a2 | 1382 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1383 | { |
3928a8a2 SR |
1384 | struct ring_buffer_event *event; |
1385 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1386 | |
d769041f SR |
1387 | /* Don't allow ftrace to trace into the ring buffers */ |
1388 | ftrace_disable_cpu(); | |
1389 | ||
1390 | if (buf_iter) | |
1391 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1392 | else | |
1393 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1394 | ||
1395 | ftrace_enable_cpu(); | |
1396 | ||
3928a8a2 | 1397 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1398 | } |
d769041f | 1399 | |
dd0e545f | 1400 | static struct trace_entry * |
3928a8a2 | 1401 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1402 | { |
3928a8a2 | 1403 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1404 | struct trace_entry *ent, *next = NULL; |
b04cc6b1 | 1405 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1406 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1407 | int next_cpu = -1; |
1408 | int cpu; | |
1409 | ||
b04cc6b1 FW |
1410 | /* |
1411 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1412 | * all cpu and peek directly. | |
1413 | */ | |
1414 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1415 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1416 | return NULL; | |
1417 | ent = peek_next_entry(iter, cpu_file, ent_ts); | |
1418 | if (ent_cpu) | |
1419 | *ent_cpu = cpu_file; | |
1420 | ||
1421 | return ent; | |
1422 | } | |
1423 | ||
ab46428c | 1424 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1425 | |
3928a8a2 SR |
1426 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1427 | continue; | |
dd0e545f | 1428 | |
3928a8a2 | 1429 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1430 | |
cdd31cd2 IM |
1431 | /* |
1432 | * Pick the entry with the smallest timestamp: | |
1433 | */ | |
3928a8a2 | 1434 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1435 | next = ent; |
1436 | next_cpu = cpu; | |
3928a8a2 | 1437 | next_ts = ts; |
bc0c38d1 SR |
1438 | } |
1439 | } | |
1440 | ||
1441 | if (ent_cpu) | |
1442 | *ent_cpu = next_cpu; | |
1443 | ||
3928a8a2 SR |
1444 | if (ent_ts) |
1445 | *ent_ts = next_ts; | |
1446 | ||
bc0c38d1 SR |
1447 | return next; |
1448 | } | |
1449 | ||
dd0e545f | 1450 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1451 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1452 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1453 | { |
3928a8a2 | 1454 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1455 | } |
1456 | ||
1457 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1458 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1459 | { | |
3928a8a2 | 1460 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1461 | |
3928a8a2 | 1462 | if (iter->ent) |
e2ac8ef5 | 1463 | trace_iterator_increment(iter); |
dd0e545f | 1464 | |
3928a8a2 | 1465 | return iter->ent ? iter : NULL; |
b3806b43 | 1466 | } |
bc0c38d1 | 1467 | |
e309b41d | 1468 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1469 | { |
d769041f SR |
1470 | /* Don't allow ftrace to trace into the ring buffers */ |
1471 | ftrace_disable_cpu(); | |
3928a8a2 | 1472 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1473 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1474 | } |
1475 | ||
e309b41d | 1476 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1477 | { |
1478 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1479 | int i = (int)*pos; |
4e3c3333 | 1480 | void *ent; |
bc0c38d1 SR |
1481 | |
1482 | (*pos)++; | |
1483 | ||
1484 | /* can't go backwards */ | |
1485 | if (iter->idx > i) | |
1486 | return NULL; | |
1487 | ||
1488 | if (iter->idx < 0) | |
1489 | ent = find_next_entry_inc(iter); | |
1490 | else | |
1491 | ent = iter; | |
1492 | ||
1493 | while (ent && iter->idx < i) | |
1494 | ent = find_next_entry_inc(iter); | |
1495 | ||
1496 | iter->pos = *pos; | |
1497 | ||
bc0c38d1 SR |
1498 | return ent; |
1499 | } | |
1500 | ||
d7350c3f FW |
1501 | /* |
1502 | * No necessary locking here. The worst thing which can | |
1503 | * happen is loosing events consumed at the same time | |
1504 | * by a trace_pipe reader. | |
1505 | * Other than that, we don't risk to crash the ring buffer | |
1506 | * because it serializes the readers. | |
1507 | * | |
1508 | * The current tracer is copied to avoid a global locking | |
1509 | * all around. | |
1510 | */ | |
bc0c38d1 SR |
1511 | static void *s_start(struct seq_file *m, loff_t *pos) |
1512 | { | |
1513 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1514 | static struct tracer *old_tracer; |
b04cc6b1 | 1515 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1516 | void *p = NULL; |
1517 | loff_t l = 0; | |
3928a8a2 | 1518 | int cpu; |
bc0c38d1 | 1519 | |
d7350c3f | 1520 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1521 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1522 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1523 | old_tracer = current_trace; | |
1524 | *iter->trace = *current_trace; | |
d15f57f2 | 1525 | } |
d7350c3f | 1526 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1527 | |
1528 | atomic_inc(&trace_record_cmdline_disabled); | |
1529 | ||
bc0c38d1 SR |
1530 | if (*pos != iter->pos) { |
1531 | iter->ent = NULL; | |
1532 | iter->cpu = 0; | |
1533 | iter->idx = -1; | |
1534 | ||
d769041f SR |
1535 | ftrace_disable_cpu(); |
1536 | ||
b04cc6b1 FW |
1537 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1538 | for_each_tracing_cpu(cpu) | |
1539 | ring_buffer_iter_reset(iter->buffer_iter[cpu]); | |
1540 | } else | |
1541 | ring_buffer_iter_reset(iter->buffer_iter[cpu_file]); | |
1542 | ||
bc0c38d1 | 1543 | |
d769041f SR |
1544 | ftrace_enable_cpu(); |
1545 | ||
bc0c38d1 SR |
1546 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1547 | ; | |
1548 | ||
1549 | } else { | |
4c11d7ae | 1550 | l = *pos - 1; |
bc0c38d1 SR |
1551 | p = s_next(m, p, &l); |
1552 | } | |
1553 | ||
1554 | return p; | |
1555 | } | |
1556 | ||
1557 | static void s_stop(struct seq_file *m, void *p) | |
1558 | { | |
bc0c38d1 | 1559 | atomic_dec(&trace_record_cmdline_disabled); |
bc0c38d1 SR |
1560 | } |
1561 | ||
e309b41d | 1562 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1563 | { |
a6168353 ME |
1564 | seq_puts(m, "# _------=> CPU# \n"); |
1565 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1566 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1567 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1568 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1569 | seq_puts(m, "# |||| / \n"); | |
1570 | seq_puts(m, "# ||||| delay \n"); | |
1571 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1572 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1573 | } |
1574 | ||
e309b41d | 1575 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1576 | { |
a6168353 ME |
1577 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1578 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1579 | } |
1580 | ||
1581 | ||
e309b41d | 1582 | static void |
bc0c38d1 SR |
1583 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1584 | { | |
1585 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1586 | struct trace_array *tr = iter->tr; | |
1587 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1588 | struct tracer *type = current_trace; | |
3928a8a2 SR |
1589 | unsigned long total; |
1590 | unsigned long entries; | |
bc0c38d1 SR |
1591 | const char *name = "preemption"; |
1592 | ||
1593 | if (type) | |
1594 | name = type->name; | |
1595 | ||
3928a8a2 SR |
1596 | entries = ring_buffer_entries(iter->tr->buffer); |
1597 | total = entries + | |
1598 | ring_buffer_overruns(iter->tr->buffer); | |
bc0c38d1 | 1599 | |
888b55dc | 1600 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1601 | name, UTS_RELEASE); |
888b55dc | 1602 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1603 | "---------------------------------\n"); |
888b55dc | 1604 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1605 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1606 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1607 | entries, |
4c11d7ae | 1608 | total, |
bc0c38d1 SR |
1609 | tr->cpu, |
1610 | #if defined(CONFIG_PREEMPT_NONE) | |
1611 | "server", | |
1612 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1613 | "desktop", | |
b5c21b45 | 1614 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1615 | "preempt", |
1616 | #else | |
1617 | "unknown", | |
1618 | #endif | |
1619 | /* These are reserved for later use */ | |
1620 | 0, 0, 0, 0); | |
1621 | #ifdef CONFIG_SMP | |
1622 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1623 | #else | |
1624 | seq_puts(m, ")\n"); | |
1625 | #endif | |
888b55dc KM |
1626 | seq_puts(m, "# -----------------\n"); |
1627 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1628 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1629 | data->comm, data->pid, data->uid, data->nice, | |
1630 | data->policy, data->rt_priority); | |
888b55dc | 1631 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1632 | |
1633 | if (data->critical_start) { | |
888b55dc | 1634 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1635 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1636 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1637 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1638 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1639 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1640 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1641 | } |
1642 | ||
888b55dc | 1643 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1644 | } |
1645 | ||
a309720c SR |
1646 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1647 | { | |
1648 | struct trace_seq *s = &iter->seq; | |
1649 | ||
12ef7d44 SR |
1650 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1651 | return; | |
1652 | ||
1653 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1654 | return; | |
1655 | ||
4462344e | 1656 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1657 | return; |
1658 | ||
4462344e | 1659 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1660 | |
1661 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1662 | if (iter->idx > 1) | |
1663 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1664 | iter->cpu); | |
a309720c SR |
1665 | } |
1666 | ||
2c4f035f | 1667 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1668 | { |
214023c3 | 1669 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1670 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1671 | struct trace_entry *entry; |
f633cef0 | 1672 | struct trace_event *event; |
bc0c38d1 | 1673 | |
4e3c3333 | 1674 | entry = iter->ent; |
dd0e545f | 1675 | |
a309720c SR |
1676 | test_cpu_buff_start(iter); |
1677 | ||
c4a8e8be | 1678 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1679 | |
c4a8e8be | 1680 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1681 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1682 | if (!trace_print_lat_context(iter)) | |
1683 | goto partial; | |
1684 | } else { | |
1685 | if (!trace_print_context(iter)) | |
1686 | goto partial; | |
1687 | } | |
c4a8e8be | 1688 | } |
bc0c38d1 | 1689 | |
268ccda0 | 1690 | if (event) |
d9793bd8 ACM |
1691 | return event->trace(iter, sym_flags); |
1692 | ||
1693 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1694 | goto partial; | |
02b67518 | 1695 | |
2c4f035f | 1696 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1697 | partial: |
1698 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1699 | } |
1700 | ||
2c4f035f | 1701 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1702 | { |
1703 | struct trace_seq *s = &iter->seq; | |
1704 | struct trace_entry *entry; | |
f633cef0 | 1705 | struct trace_event *event; |
f9896bf3 IM |
1706 | |
1707 | entry = iter->ent; | |
dd0e545f | 1708 | |
c4a8e8be | 1709 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1710 | if (!trace_seq_printf(s, "%d %d %llu ", |
1711 | entry->pid, iter->cpu, iter->ts)) | |
1712 | goto partial; | |
c4a8e8be | 1713 | } |
f9896bf3 | 1714 | |
f633cef0 | 1715 | event = ftrace_find_event(entry->type); |
268ccda0 | 1716 | if (event) |
d9793bd8 ACM |
1717 | return event->raw(iter, 0); |
1718 | ||
1719 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1720 | goto partial; | |
777e208d | 1721 | |
2c4f035f | 1722 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1723 | partial: |
1724 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1725 | } |
1726 | ||
2c4f035f | 1727 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1728 | { |
1729 | struct trace_seq *s = &iter->seq; | |
1730 | unsigned char newline = '\n'; | |
1731 | struct trace_entry *entry; | |
f633cef0 | 1732 | struct trace_event *event; |
5e3ca0ec IM |
1733 | |
1734 | entry = iter->ent; | |
dd0e545f | 1735 | |
c4a8e8be FW |
1736 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1737 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1738 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1739 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1740 | } | |
5e3ca0ec | 1741 | |
f633cef0 | 1742 | event = ftrace_find_event(entry->type); |
268ccda0 | 1743 | if (event) { |
ae7462b4 | 1744 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1745 | if (ret != TRACE_TYPE_HANDLED) |
1746 | return ret; | |
1747 | } | |
7104f300 | 1748 | |
5e3ca0ec IM |
1749 | SEQ_PUT_FIELD_RET(s, newline); |
1750 | ||
2c4f035f | 1751 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1752 | } |
1753 | ||
2c4f035f | 1754 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1755 | { |
1756 | struct trace_seq *s = &iter->seq; | |
1757 | struct trace_entry *entry; | |
f633cef0 | 1758 | struct trace_event *event; |
cb0f12aa IM |
1759 | |
1760 | entry = iter->ent; | |
dd0e545f | 1761 | |
c4a8e8be FW |
1762 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1763 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1764 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1765 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1766 | } | |
cb0f12aa | 1767 | |
f633cef0 | 1768 | event = ftrace_find_event(entry->type); |
268ccda0 | 1769 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1770 | } |
1771 | ||
bc0c38d1 SR |
1772 | static int trace_empty(struct trace_iterator *iter) |
1773 | { | |
bc0c38d1 SR |
1774 | int cpu; |
1775 | ||
9aba60fe SR |
1776 | /* If we are looking at one CPU buffer, only check that one */ |
1777 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1778 | cpu = iter->cpu_file; | |
1779 | if (iter->buffer_iter[cpu]) { | |
1780 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1781 | return 0; | |
1782 | } else { | |
1783 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1784 | return 0; | |
1785 | } | |
1786 | return 1; | |
1787 | } | |
1788 | ||
ab46428c | 1789 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1790 | if (iter->buffer_iter[cpu]) { |
1791 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1792 | return 0; | |
1793 | } else { | |
1794 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1795 | return 0; | |
1796 | } | |
bc0c38d1 | 1797 | } |
d769041f | 1798 | |
797d3712 | 1799 | return 1; |
bc0c38d1 SR |
1800 | } |
1801 | ||
2c4f035f | 1802 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1803 | { |
2c4f035f FW |
1804 | enum print_line_t ret; |
1805 | ||
1806 | if (iter->trace && iter->trace->print_line) { | |
1807 | ret = iter->trace->print_line(iter); | |
1808 | if (ret != TRACE_TYPE_UNHANDLED) | |
1809 | return ret; | |
1810 | } | |
72829bc3 | 1811 | |
48ead020 FW |
1812 | if (iter->ent->type == TRACE_BPRINT && |
1813 | trace_flags & TRACE_ITER_PRINTK && | |
1814 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1815 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 1816 | |
66896a85 FW |
1817 | if (iter->ent->type == TRACE_PRINT && |
1818 | trace_flags & TRACE_ITER_PRINTK && | |
1819 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1820 | return trace_print_printk_msg_only(iter); |
66896a85 | 1821 | |
cb0f12aa IM |
1822 | if (trace_flags & TRACE_ITER_BIN) |
1823 | return print_bin_fmt(iter); | |
1824 | ||
5e3ca0ec IM |
1825 | if (trace_flags & TRACE_ITER_HEX) |
1826 | return print_hex_fmt(iter); | |
1827 | ||
f9896bf3 IM |
1828 | if (trace_flags & TRACE_ITER_RAW) |
1829 | return print_raw_fmt(iter); | |
1830 | ||
f9896bf3 IM |
1831 | return print_trace_fmt(iter); |
1832 | } | |
1833 | ||
bc0c38d1 SR |
1834 | static int s_show(struct seq_file *m, void *v) |
1835 | { | |
1836 | struct trace_iterator *iter = v; | |
1837 | ||
1838 | if (iter->ent == NULL) { | |
1839 | if (iter->tr) { | |
1840 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1841 | seq_puts(m, "#\n"); | |
1842 | } | |
8bba1bf5 MM |
1843 | if (iter->trace && iter->trace->print_header) |
1844 | iter->trace->print_header(m); | |
1845 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
1846 | /* print nothing if the buffers are empty */ |
1847 | if (trace_empty(iter)) | |
1848 | return 0; | |
1849 | print_trace_header(m, iter); | |
1850 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1851 | print_lat_help_header(m); | |
1852 | } else { | |
1853 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1854 | print_func_help_header(m); | |
1855 | } | |
1856 | } else { | |
f9896bf3 | 1857 | print_trace_line(iter); |
214023c3 | 1858 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1859 | } |
1860 | ||
1861 | return 0; | |
1862 | } | |
1863 | ||
1864 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1865 | .start = s_start, |
1866 | .next = s_next, | |
1867 | .stop = s_stop, | |
1868 | .show = s_show, | |
bc0c38d1 SR |
1869 | }; |
1870 | ||
e309b41d | 1871 | static struct trace_iterator * |
85a2f9b4 | 1872 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 1873 | { |
b04cc6b1 | 1874 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 1875 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 1876 | struct trace_iterator *iter; |
3928a8a2 | 1877 | struct seq_file *m; |
85a2f9b4 | 1878 | int cpu, ret; |
bc0c38d1 | 1879 | |
85a2f9b4 SR |
1880 | if (tracing_disabled) |
1881 | return ERR_PTR(-ENODEV); | |
60a11774 | 1882 | |
bc0c38d1 | 1883 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
1884 | if (!iter) |
1885 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 1886 | |
d7350c3f FW |
1887 | /* |
1888 | * We make a copy of the current tracer to avoid concurrent | |
1889 | * changes on it while we are reading. | |
1890 | */ | |
bc0c38d1 | 1891 | mutex_lock(&trace_types_lock); |
d7350c3f | 1892 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 1893 | if (!iter->trace) |
d7350c3f | 1894 | goto fail; |
85a2f9b4 | 1895 | |
d7350c3f FW |
1896 | if (current_trace) |
1897 | *iter->trace = *current_trace; | |
1898 | ||
b0dfa978 FW |
1899 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) |
1900 | goto fail; | |
1901 | ||
1902 | cpumask_clear(iter->started); | |
1903 | ||
bc0c38d1 SR |
1904 | if (current_trace && current_trace->print_max) |
1905 | iter->tr = &max_tr; | |
1906 | else | |
b04cc6b1 | 1907 | iter->tr = &global_trace; |
bc0c38d1 | 1908 | iter->pos = -1; |
d7350c3f | 1909 | mutex_init(&iter->mutex); |
b04cc6b1 | 1910 | iter->cpu_file = cpu_file; |
bc0c38d1 | 1911 | |
8bba1bf5 MM |
1912 | /* Notify the tracer early; before we stop tracing. */ |
1913 | if (iter->trace && iter->trace->open) | |
a93751ca | 1914 | iter->trace->open(iter); |
8bba1bf5 | 1915 | |
12ef7d44 SR |
1916 | /* Annotate start of buffers if we had overruns */ |
1917 | if (ring_buffer_overruns(iter->tr->buffer)) | |
1918 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
1919 | ||
b04cc6b1 FW |
1920 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
1921 | for_each_tracing_cpu(cpu) { | |
12ef7d44 | 1922 | |
b04cc6b1 FW |
1923 | iter->buffer_iter[cpu] = |
1924 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
b04cc6b1 FW |
1925 | } |
1926 | } else { | |
1927 | cpu = iter->cpu_file; | |
3928a8a2 | 1928 | iter->buffer_iter[cpu] = |
b04cc6b1 | 1929 | ring_buffer_read_start(iter->tr->buffer, cpu); |
3928a8a2 SR |
1930 | } |
1931 | ||
bc0c38d1 | 1932 | /* TODO stop tracer */ |
85a2f9b4 SR |
1933 | ret = seq_open(file, &tracer_seq_ops); |
1934 | if (ret < 0) { | |
1935 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 1936 | goto fail_buffer; |
85a2f9b4 | 1937 | } |
bc0c38d1 | 1938 | |
3928a8a2 SR |
1939 | m = file->private_data; |
1940 | m->private = iter; | |
bc0c38d1 | 1941 | |
3928a8a2 | 1942 | /* stop the trace while dumping */ |
9036990d | 1943 | tracing_stop(); |
3928a8a2 | 1944 | |
bc0c38d1 SR |
1945 | mutex_unlock(&trace_types_lock); |
1946 | ||
bc0c38d1 | 1947 | return iter; |
3928a8a2 SR |
1948 | |
1949 | fail_buffer: | |
1950 | for_each_tracing_cpu(cpu) { | |
1951 | if (iter->buffer_iter[cpu]) | |
1952 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1953 | } | |
b0dfa978 | 1954 | free_cpumask_var(iter->started); |
d7350c3f | 1955 | fail: |
3928a8a2 | 1956 | mutex_unlock(&trace_types_lock); |
d7350c3f | 1957 | kfree(iter->trace); |
0bb943c7 | 1958 | kfree(iter); |
3928a8a2 | 1959 | |
85a2f9b4 | 1960 | return fail_ret; |
bc0c38d1 SR |
1961 | } |
1962 | ||
1963 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1964 | { | |
60a11774 SR |
1965 | if (tracing_disabled) |
1966 | return -ENODEV; | |
1967 | ||
bc0c38d1 SR |
1968 | filp->private_data = inode->i_private; |
1969 | return 0; | |
1970 | } | |
1971 | ||
4fd27358 | 1972 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
1973 | { |
1974 | struct seq_file *m = (struct seq_file *)file->private_data; | |
4acd4d00 | 1975 | struct trace_iterator *iter; |
3928a8a2 | 1976 | int cpu; |
bc0c38d1 | 1977 | |
4acd4d00 SR |
1978 | if (!(file->f_mode & FMODE_READ)) |
1979 | return 0; | |
1980 | ||
1981 | iter = m->private; | |
1982 | ||
bc0c38d1 | 1983 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
1984 | for_each_tracing_cpu(cpu) { |
1985 | if (iter->buffer_iter[cpu]) | |
1986 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1987 | } | |
1988 | ||
bc0c38d1 SR |
1989 | if (iter->trace && iter->trace->close) |
1990 | iter->trace->close(iter); | |
1991 | ||
1992 | /* reenable tracing if it was previously enabled */ | |
9036990d | 1993 | tracing_start(); |
bc0c38d1 SR |
1994 | mutex_unlock(&trace_types_lock); |
1995 | ||
1996 | seq_release(inode, file); | |
d7350c3f | 1997 | mutex_destroy(&iter->mutex); |
b0dfa978 | 1998 | free_cpumask_var(iter->started); |
d7350c3f | 1999 | kfree(iter->trace); |
bc0c38d1 SR |
2000 | kfree(iter); |
2001 | return 0; | |
2002 | } | |
2003 | ||
2004 | static int tracing_open(struct inode *inode, struct file *file) | |
2005 | { | |
85a2f9b4 SR |
2006 | struct trace_iterator *iter; |
2007 | int ret = 0; | |
bc0c38d1 | 2008 | |
4acd4d00 SR |
2009 | /* If this file was open for write, then erase contents */ |
2010 | if ((file->f_mode & FMODE_WRITE) && | |
2011 | !(file->f_flags & O_APPEND)) { | |
2012 | long cpu = (long) inode->i_private; | |
bc0c38d1 | 2013 | |
4acd4d00 SR |
2014 | if (cpu == TRACE_PIPE_ALL_CPU) |
2015 | tracing_reset_online_cpus(&global_trace); | |
2016 | else | |
2017 | tracing_reset(&global_trace, cpu); | |
2018 | } | |
bc0c38d1 | 2019 | |
4acd4d00 SR |
2020 | if (file->f_mode & FMODE_READ) { |
2021 | iter = __tracing_open(inode, file); | |
2022 | if (IS_ERR(iter)) | |
2023 | ret = PTR_ERR(iter); | |
2024 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2025 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2026 | } | |
bc0c38d1 SR |
2027 | return ret; |
2028 | } | |
2029 | ||
e309b41d | 2030 | static void * |
bc0c38d1 SR |
2031 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2032 | { | |
2033 | struct tracer *t = m->private; | |
2034 | ||
2035 | (*pos)++; | |
2036 | ||
2037 | if (t) | |
2038 | t = t->next; | |
2039 | ||
2040 | m->private = t; | |
2041 | ||
2042 | return t; | |
2043 | } | |
2044 | ||
2045 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2046 | { | |
2047 | struct tracer *t = m->private; | |
2048 | loff_t l = 0; | |
2049 | ||
2050 | mutex_lock(&trace_types_lock); | |
2051 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
2052 | ; | |
2053 | ||
2054 | return t; | |
2055 | } | |
2056 | ||
2057 | static void t_stop(struct seq_file *m, void *p) | |
2058 | { | |
2059 | mutex_unlock(&trace_types_lock); | |
2060 | } | |
2061 | ||
2062 | static int t_show(struct seq_file *m, void *v) | |
2063 | { | |
2064 | struct tracer *t = v; | |
2065 | ||
2066 | if (!t) | |
2067 | return 0; | |
2068 | ||
2069 | seq_printf(m, "%s", t->name); | |
2070 | if (t->next) | |
2071 | seq_putc(m, ' '); | |
2072 | else | |
2073 | seq_putc(m, '\n'); | |
2074 | ||
2075 | return 0; | |
2076 | } | |
2077 | ||
2078 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
2079 | .start = t_start, |
2080 | .next = t_next, | |
2081 | .stop = t_stop, | |
2082 | .show = t_show, | |
bc0c38d1 SR |
2083 | }; |
2084 | ||
2085 | static int show_traces_open(struct inode *inode, struct file *file) | |
2086 | { | |
2087 | int ret; | |
2088 | ||
60a11774 SR |
2089 | if (tracing_disabled) |
2090 | return -ENODEV; | |
2091 | ||
bc0c38d1 SR |
2092 | ret = seq_open(file, &show_traces_seq_ops); |
2093 | if (!ret) { | |
2094 | struct seq_file *m = file->private_data; | |
2095 | m->private = trace_types; | |
2096 | } | |
2097 | ||
2098 | return ret; | |
2099 | } | |
2100 | ||
4acd4d00 SR |
2101 | static ssize_t |
2102 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2103 | size_t count, loff_t *ppos) | |
2104 | { | |
2105 | return count; | |
2106 | } | |
2107 | ||
5e2336a0 | 2108 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2109 | .open = tracing_open, |
2110 | .read = seq_read, | |
4acd4d00 | 2111 | .write = tracing_write_stub, |
4bf39a94 IM |
2112 | .llseek = seq_lseek, |
2113 | .release = tracing_release, | |
bc0c38d1 SR |
2114 | }; |
2115 | ||
5e2336a0 | 2116 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2117 | .open = show_traces_open, |
2118 | .read = seq_read, | |
2119 | .release = seq_release, | |
2120 | }; | |
2121 | ||
36dfe925 IM |
2122 | /* |
2123 | * Only trace on a CPU if the bitmask is set: | |
2124 | */ | |
9e01c1b7 | 2125 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2126 | |
2127 | /* | |
2128 | * The tracer itself will not take this lock, but still we want | |
2129 | * to provide a consistent cpumask to user-space: | |
2130 | */ | |
2131 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2132 | ||
2133 | /* | |
2134 | * Temporary storage for the character representation of the | |
2135 | * CPU bitmask (and one more byte for the newline): | |
2136 | */ | |
2137 | static char mask_str[NR_CPUS + 1]; | |
2138 | ||
c7078de1 IM |
2139 | static ssize_t |
2140 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2141 | size_t count, loff_t *ppos) | |
2142 | { | |
36dfe925 | 2143 | int len; |
c7078de1 IM |
2144 | |
2145 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2146 | |
9e01c1b7 | 2147 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2148 | if (count - len < 2) { |
2149 | count = -EINVAL; | |
2150 | goto out_err; | |
2151 | } | |
2152 | len += sprintf(mask_str + len, "\n"); | |
2153 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2154 | ||
2155 | out_err: | |
c7078de1 IM |
2156 | mutex_unlock(&tracing_cpumask_update_lock); |
2157 | ||
2158 | return count; | |
2159 | } | |
2160 | ||
2161 | static ssize_t | |
2162 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2163 | size_t count, loff_t *ppos) | |
2164 | { | |
36dfe925 | 2165 | int err, cpu; |
9e01c1b7 RR |
2166 | cpumask_var_t tracing_cpumask_new; |
2167 | ||
2168 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2169 | return -ENOMEM; | |
c7078de1 IM |
2170 | |
2171 | mutex_lock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2172 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2173 | if (err) |
36dfe925 IM |
2174 | goto err_unlock; |
2175 | ||
a5e25883 | 2176 | local_irq_disable(); |
92205c23 | 2177 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 2178 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2179 | /* |
2180 | * Increase/decrease the disabled counter if we are | |
2181 | * about to flip a bit in the cpumask: | |
2182 | */ | |
9e01c1b7 RR |
2183 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2184 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2185 | atomic_inc(&global_trace.data[cpu]->disabled); |
2186 | } | |
9e01c1b7 RR |
2187 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2188 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2189 | atomic_dec(&global_trace.data[cpu]->disabled); |
2190 | } | |
2191 | } | |
92205c23 | 2192 | __raw_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2193 | local_irq_enable(); |
36dfe925 | 2194 | |
9e01c1b7 | 2195 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2196 | |
2197 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2198 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2199 | |
2200 | return count; | |
36dfe925 IM |
2201 | |
2202 | err_unlock: | |
2203 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2204 | free_cpumask_var(tracing_cpumask); |
36dfe925 IM |
2205 | |
2206 | return err; | |
c7078de1 IM |
2207 | } |
2208 | ||
5e2336a0 | 2209 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2210 | .open = tracing_open_generic, |
2211 | .read = tracing_cpumask_read, | |
2212 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2213 | }; |
2214 | ||
2215 | static ssize_t | |
ee6bce52 | 2216 | tracing_trace_options_read(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
2217 | size_t cnt, loff_t *ppos) |
2218 | { | |
d8e83d26 SR |
2219 | struct tracer_opt *trace_opts; |
2220 | u32 tracer_flags; | |
2221 | int len = 0; | |
bc0c38d1 SR |
2222 | char *buf; |
2223 | int r = 0; | |
d8e83d26 | 2224 | int i; |
adf9f195 | 2225 | |
bc0c38d1 | 2226 | |
c3706f00 | 2227 | /* calculate max size */ |
bc0c38d1 SR |
2228 | for (i = 0; trace_options[i]; i++) { |
2229 | len += strlen(trace_options[i]); | |
5c6a3ae1 | 2230 | len += 3; /* "no" and newline */ |
bc0c38d1 SR |
2231 | } |
2232 | ||
d8e83d26 SR |
2233 | mutex_lock(&trace_types_lock); |
2234 | tracer_flags = current_trace->flags->val; | |
2235 | trace_opts = current_trace->flags->opts; | |
2236 | ||
adf9f195 FW |
2237 | /* |
2238 | * Increase the size with names of options specific | |
2239 | * of the current tracer. | |
2240 | */ | |
2241 | for (i = 0; trace_opts[i].name; i++) { | |
2242 | len += strlen(trace_opts[i].name); | |
5c6a3ae1 | 2243 | len += 3; /* "no" and newline */ |
adf9f195 FW |
2244 | } |
2245 | ||
bc0c38d1 SR |
2246 | /* +2 for \n and \0 */ |
2247 | buf = kmalloc(len + 2, GFP_KERNEL); | |
d8e83d26 SR |
2248 | if (!buf) { |
2249 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 2250 | return -ENOMEM; |
d8e83d26 | 2251 | } |
bc0c38d1 SR |
2252 | |
2253 | for (i = 0; trace_options[i]; i++) { | |
2254 | if (trace_flags & (1 << i)) | |
5c6a3ae1 | 2255 | r += sprintf(buf + r, "%s\n", trace_options[i]); |
bc0c38d1 | 2256 | else |
5c6a3ae1 | 2257 | r += sprintf(buf + r, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2258 | } |
2259 | ||
adf9f195 FW |
2260 | for (i = 0; trace_opts[i].name; i++) { |
2261 | if (tracer_flags & trace_opts[i].bit) | |
5c6a3ae1 | 2262 | r += sprintf(buf + r, "%s\n", |
adf9f195 FW |
2263 | trace_opts[i].name); |
2264 | else | |
5c6a3ae1 | 2265 | r += sprintf(buf + r, "no%s\n", |
adf9f195 FW |
2266 | trace_opts[i].name); |
2267 | } | |
d8e83d26 | 2268 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2269 | |
bc0c38d1 SR |
2270 | WARN_ON(r >= len + 2); |
2271 | ||
36dfe925 | 2272 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2273 | |
2274 | kfree(buf); | |
bc0c38d1 SR |
2275 | return r; |
2276 | } | |
2277 | ||
adf9f195 FW |
2278 | /* Try to assign a tracer specific option */ |
2279 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2280 | { | |
2281 | struct tracer_flags *trace_flags = trace->flags; | |
2282 | struct tracer_opt *opts = NULL; | |
2283 | int ret = 0, i = 0; | |
2284 | int len; | |
2285 | ||
2286 | for (i = 0; trace_flags->opts[i].name; i++) { | |
2287 | opts = &trace_flags->opts[i]; | |
2288 | len = strlen(opts->name); | |
2289 | ||
2290 | if (strncmp(cmp, opts->name, len) == 0) { | |
2291 | ret = trace->set_flag(trace_flags->val, | |
2292 | opts->bit, !neg); | |
2293 | break; | |
2294 | } | |
2295 | } | |
2296 | /* Not found */ | |
2297 | if (!trace_flags->opts[i].name) | |
2298 | return -EINVAL; | |
2299 | ||
2300 | /* Refused to handle */ | |
2301 | if (ret) | |
2302 | return ret; | |
2303 | ||
2304 | if (neg) | |
2305 | trace_flags->val &= ~opts->bit; | |
2306 | else | |
2307 | trace_flags->val |= opts->bit; | |
2308 | ||
2309 | return 0; | |
2310 | } | |
2311 | ||
af4617bd SR |
2312 | static void set_tracer_flags(unsigned int mask, int enabled) |
2313 | { | |
2314 | /* do nothing if flag is already set */ | |
2315 | if (!!(trace_flags & mask) == !!enabled) | |
2316 | return; | |
2317 | ||
2318 | if (enabled) | |
2319 | trace_flags |= mask; | |
2320 | else | |
2321 | trace_flags &= ~mask; | |
2322 | ||
2323 | if (mask == TRACE_ITER_GLOBAL_CLK) { | |
2324 | u64 (*func)(void); | |
2325 | ||
2326 | if (enabled) | |
2327 | func = trace_clock_global; | |
2328 | else | |
2329 | func = trace_clock_local; | |
2330 | ||
2331 | mutex_lock(&trace_types_lock); | |
2332 | ring_buffer_set_clock(global_trace.buffer, func); | |
2333 | ||
2334 | if (max_tr.buffer) | |
2335 | ring_buffer_set_clock(max_tr.buffer, func); | |
2336 | mutex_unlock(&trace_types_lock); | |
2337 | } | |
2338 | } | |
2339 | ||
bc0c38d1 | 2340 | static ssize_t |
ee6bce52 | 2341 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2342 | size_t cnt, loff_t *ppos) |
2343 | { | |
2344 | char buf[64]; | |
2345 | char *cmp = buf; | |
2346 | int neg = 0; | |
adf9f195 | 2347 | int ret; |
bc0c38d1 SR |
2348 | int i; |
2349 | ||
cffae437 SR |
2350 | if (cnt >= sizeof(buf)) |
2351 | return -EINVAL; | |
bc0c38d1 SR |
2352 | |
2353 | if (copy_from_user(&buf, ubuf, cnt)) | |
2354 | return -EFAULT; | |
2355 | ||
2356 | buf[cnt] = 0; | |
2357 | ||
2358 | if (strncmp(buf, "no", 2) == 0) { | |
2359 | neg = 1; | |
2360 | cmp += 2; | |
2361 | } | |
2362 | ||
2363 | for (i = 0; trace_options[i]; i++) { | |
2364 | int len = strlen(trace_options[i]); | |
2365 | ||
2366 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
af4617bd | 2367 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2368 | break; |
2369 | } | |
2370 | } | |
adf9f195 FW |
2371 | |
2372 | /* If no option could be set, test the specific tracer options */ | |
2373 | if (!trace_options[i]) { | |
d8e83d26 | 2374 | mutex_lock(&trace_types_lock); |
adf9f195 | 2375 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2376 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2377 | if (ret) |
2378 | return ret; | |
2379 | } | |
bc0c38d1 SR |
2380 | |
2381 | filp->f_pos += cnt; | |
2382 | ||
2383 | return cnt; | |
2384 | } | |
2385 | ||
5e2336a0 | 2386 | static const struct file_operations tracing_iter_fops = { |
c7078de1 | 2387 | .open = tracing_open_generic, |
ee6bce52 SR |
2388 | .read = tracing_trace_options_read, |
2389 | .write = tracing_trace_options_write, | |
bc0c38d1 SR |
2390 | }; |
2391 | ||
7bd2f24c IM |
2392 | static const char readme_msg[] = |
2393 | "tracing mini-HOWTO:\n\n" | |
2394 | "# mkdir /debug\n" | |
2395 | "# mount -t debugfs nodev /debug\n\n" | |
2396 | "# cat /debug/tracing/available_tracers\n" | |
bc2b6871 | 2397 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
7bd2f24c | 2398 | "# cat /debug/tracing/current_tracer\n" |
bc2b6871 | 2399 | "nop\n" |
7bd2f24c IM |
2400 | "# echo sched_switch > /debug/tracing/current_tracer\n" |
2401 | "# cat /debug/tracing/current_tracer\n" | |
2402 | "sched_switch\n" | |
ee6bce52 | 2403 | "# cat /debug/tracing/trace_options\n" |
7bd2f24c | 2404 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
ee6bce52 | 2405 | "# echo print-parent > /debug/tracing/trace_options\n" |
7bd2f24c IM |
2406 | "# echo 1 > /debug/tracing/tracing_enabled\n" |
2407 | "# cat /debug/tracing/trace > /tmp/trace.txt\n" | |
2408 | "echo 0 > /debug/tracing/tracing_enabled\n" | |
2409 | ; | |
2410 | ||
2411 | static ssize_t | |
2412 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2413 | size_t cnt, loff_t *ppos) | |
2414 | { | |
2415 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2416 | readme_msg, strlen(readme_msg)); | |
2417 | } | |
2418 | ||
5e2336a0 | 2419 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2420 | .open = tracing_open_generic, |
2421 | .read = tracing_readme_read, | |
7bd2f24c IM |
2422 | }; |
2423 | ||
69abe6a5 AP |
2424 | static ssize_t |
2425 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2426 | size_t cnt, loff_t *ppos) | |
2427 | { | |
2428 | char *buf_comm; | |
2429 | char *file_buf; | |
2430 | char *buf; | |
2431 | int len = 0; | |
2432 | int pid; | |
2433 | int i; | |
2434 | ||
2435 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2436 | if (!file_buf) | |
2437 | return -ENOMEM; | |
2438 | ||
2439 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2440 | if (!buf_comm) { | |
2441 | kfree(file_buf); | |
2442 | return -ENOMEM; | |
2443 | } | |
2444 | ||
2445 | buf = file_buf; | |
2446 | ||
2447 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2448 | int r; | |
2449 | ||
2450 | pid = map_cmdline_to_pid[i]; | |
2451 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2452 | continue; | |
2453 | ||
2454 | trace_find_cmdline(pid, buf_comm); | |
2455 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2456 | buf += r; | |
2457 | len += r; | |
2458 | } | |
2459 | ||
2460 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2461 | file_buf, len); | |
2462 | ||
2463 | kfree(file_buf); | |
2464 | kfree(buf_comm); | |
2465 | ||
2466 | return len; | |
2467 | } | |
2468 | ||
2469 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2470 | .open = tracing_open_generic, | |
2471 | .read = tracing_saved_cmdlines_read, | |
2472 | }; | |
2473 | ||
bc0c38d1 SR |
2474 | static ssize_t |
2475 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2476 | size_t cnt, loff_t *ppos) | |
2477 | { | |
bc0c38d1 SR |
2478 | char buf[64]; |
2479 | int r; | |
2480 | ||
9036990d | 2481 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2482 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2483 | } |
2484 | ||
2485 | static ssize_t | |
2486 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2487 | size_t cnt, loff_t *ppos) | |
2488 | { | |
2489 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2490 | char buf[64]; |
5e39841c | 2491 | unsigned long val; |
c6caeeb1 | 2492 | int ret; |
bc0c38d1 | 2493 | |
cffae437 SR |
2494 | if (cnt >= sizeof(buf)) |
2495 | return -EINVAL; | |
bc0c38d1 SR |
2496 | |
2497 | if (copy_from_user(&buf, ubuf, cnt)) | |
2498 | return -EFAULT; | |
2499 | ||
2500 | buf[cnt] = 0; | |
2501 | ||
c6caeeb1 SR |
2502 | ret = strict_strtoul(buf, 10, &val); |
2503 | if (ret < 0) | |
2504 | return ret; | |
bc0c38d1 SR |
2505 | |
2506 | val = !!val; | |
2507 | ||
2508 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2509 | if (tracer_enabled ^ val) { |
2510 | if (val) { | |
bc0c38d1 | 2511 | tracer_enabled = 1; |
9036990d SR |
2512 | if (current_trace->start) |
2513 | current_trace->start(tr); | |
2514 | tracing_start(); | |
2515 | } else { | |
bc0c38d1 | 2516 | tracer_enabled = 0; |
9036990d SR |
2517 | tracing_stop(); |
2518 | if (current_trace->stop) | |
2519 | current_trace->stop(tr); | |
2520 | } | |
bc0c38d1 SR |
2521 | } |
2522 | mutex_unlock(&trace_types_lock); | |
2523 | ||
2524 | filp->f_pos += cnt; | |
2525 | ||
2526 | return cnt; | |
2527 | } | |
2528 | ||
2529 | static ssize_t | |
2530 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2531 | size_t cnt, loff_t *ppos) | |
2532 | { | |
2533 | char buf[max_tracer_type_len+2]; | |
2534 | int r; | |
2535 | ||
2536 | mutex_lock(&trace_types_lock); | |
2537 | if (current_trace) | |
2538 | r = sprintf(buf, "%s\n", current_trace->name); | |
2539 | else | |
2540 | r = sprintf(buf, "\n"); | |
2541 | mutex_unlock(&trace_types_lock); | |
2542 | ||
4bf39a94 | 2543 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2544 | } |
2545 | ||
b6f11df2 ACM |
2546 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2547 | { | |
2548 | tracing_reset_online_cpus(tr); | |
2549 | return t->init(tr); | |
2550 | } | |
2551 | ||
73c5162a SR |
2552 | static int tracing_resize_ring_buffer(unsigned long size) |
2553 | { | |
2554 | int ret; | |
2555 | ||
2556 | /* | |
2557 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2558 | * we use the size that was given, and we can forget about |
2559 | * expanding it later. | |
73c5162a SR |
2560 | */ |
2561 | ring_buffer_expanded = 1; | |
2562 | ||
2563 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2564 | if (ret < 0) | |
2565 | return ret; | |
2566 | ||
2567 | ret = ring_buffer_resize(max_tr.buffer, size); | |
2568 | if (ret < 0) { | |
2569 | int r; | |
2570 | ||
2571 | r = ring_buffer_resize(global_trace.buffer, | |
2572 | global_trace.entries); | |
2573 | if (r < 0) { | |
a123c52b SR |
2574 | /* |
2575 | * AARGH! We are left with different | |
2576 | * size max buffer!!!! | |
2577 | * The max buffer is our "snapshot" buffer. | |
2578 | * When a tracer needs a snapshot (one of the | |
2579 | * latency tracers), it swaps the max buffer | |
2580 | * with the saved snap shot. We succeeded to | |
2581 | * update the size of the main buffer, but failed to | |
2582 | * update the size of the max buffer. But when we tried | |
2583 | * to reset the main buffer to the original size, we | |
2584 | * failed there too. This is very unlikely to | |
2585 | * happen, but if it does, warn and kill all | |
2586 | * tracing. | |
2587 | */ | |
73c5162a SR |
2588 | WARN_ON(1); |
2589 | tracing_disabled = 1; | |
2590 | } | |
2591 | return ret; | |
2592 | } | |
2593 | ||
2594 | global_trace.entries = size; | |
2595 | ||
2596 | return ret; | |
2597 | } | |
2598 | ||
1852fcce SR |
2599 | /** |
2600 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2601 | * | |
2602 | * To save on memory when the tracing is never used on a system with it | |
2603 | * configured in. The ring buffers are set to a minimum size. But once | |
2604 | * a user starts to use the tracing facility, then they need to grow | |
2605 | * to their default size. | |
2606 | * | |
2607 | * This function is to be called when a tracer is about to be used. | |
2608 | */ | |
2609 | int tracing_update_buffers(void) | |
2610 | { | |
2611 | int ret = 0; | |
2612 | ||
1027fcb2 | 2613 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2614 | if (!ring_buffer_expanded) |
2615 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2616 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2617 | |
2618 | return ret; | |
2619 | } | |
2620 | ||
577b785f SR |
2621 | struct trace_option_dentry; |
2622 | ||
2623 | static struct trace_option_dentry * | |
2624 | create_trace_option_files(struct tracer *tracer); | |
2625 | ||
2626 | static void | |
2627 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2628 | ||
b2821ae6 | 2629 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2630 | { |
577b785f | 2631 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2632 | struct trace_array *tr = &global_trace; |
2633 | struct tracer *t; | |
d9e54076 | 2634 | int ret = 0; |
bc0c38d1 | 2635 | |
1027fcb2 SR |
2636 | mutex_lock(&trace_types_lock); |
2637 | ||
73c5162a SR |
2638 | if (!ring_buffer_expanded) { |
2639 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2640 | if (ret < 0) | |
59f586db | 2641 | goto out; |
73c5162a SR |
2642 | ret = 0; |
2643 | } | |
2644 | ||
bc0c38d1 SR |
2645 | for (t = trace_types; t; t = t->next) { |
2646 | if (strcmp(t->name, buf) == 0) | |
2647 | break; | |
2648 | } | |
c2931e05 FW |
2649 | if (!t) { |
2650 | ret = -EINVAL; | |
2651 | goto out; | |
2652 | } | |
2653 | if (t == current_trace) | |
bc0c38d1 SR |
2654 | goto out; |
2655 | ||
9f029e83 | 2656 | trace_branch_disable(); |
bc0c38d1 SR |
2657 | if (current_trace && current_trace->reset) |
2658 | current_trace->reset(tr); | |
2659 | ||
577b785f SR |
2660 | destroy_trace_option_files(topts); |
2661 | ||
bc0c38d1 | 2662 | current_trace = t; |
577b785f SR |
2663 | |
2664 | topts = create_trace_option_files(current_trace); | |
2665 | ||
1c80025a | 2666 | if (t->init) { |
b6f11df2 | 2667 | ret = tracer_init(t, tr); |
1c80025a FW |
2668 | if (ret) |
2669 | goto out; | |
2670 | } | |
bc0c38d1 | 2671 | |
9f029e83 | 2672 | trace_branch_enable(tr); |
bc0c38d1 SR |
2673 | out: |
2674 | mutex_unlock(&trace_types_lock); | |
2675 | ||
d9e54076 PZ |
2676 | return ret; |
2677 | } | |
2678 | ||
2679 | static ssize_t | |
2680 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2681 | size_t cnt, loff_t *ppos) | |
2682 | { | |
2683 | char buf[max_tracer_type_len+1]; | |
2684 | int i; | |
2685 | size_t ret; | |
e6e7a65a FW |
2686 | int err; |
2687 | ||
2688 | ret = cnt; | |
d9e54076 PZ |
2689 | |
2690 | if (cnt > max_tracer_type_len) | |
2691 | cnt = max_tracer_type_len; | |
2692 | ||
2693 | if (copy_from_user(&buf, ubuf, cnt)) | |
2694 | return -EFAULT; | |
2695 | ||
2696 | buf[cnt] = 0; | |
2697 | ||
2698 | /* strip ending whitespace. */ | |
2699 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2700 | buf[i] = 0; | |
2701 | ||
e6e7a65a FW |
2702 | err = tracing_set_tracer(buf); |
2703 | if (err) | |
2704 | return err; | |
d9e54076 | 2705 | |
e6e7a65a | 2706 | filp->f_pos += ret; |
bc0c38d1 | 2707 | |
c2931e05 | 2708 | return ret; |
bc0c38d1 SR |
2709 | } |
2710 | ||
2711 | static ssize_t | |
2712 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2713 | size_t cnt, loff_t *ppos) | |
2714 | { | |
2715 | unsigned long *ptr = filp->private_data; | |
2716 | char buf[64]; | |
2717 | int r; | |
2718 | ||
cffae437 | 2719 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2720 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2721 | if (r > sizeof(buf)) |
2722 | r = sizeof(buf); | |
4bf39a94 | 2723 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2724 | } |
2725 | ||
2726 | static ssize_t | |
2727 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2728 | size_t cnt, loff_t *ppos) | |
2729 | { | |
5e39841c | 2730 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2731 | char buf[64]; |
5e39841c | 2732 | unsigned long val; |
c6caeeb1 | 2733 | int ret; |
bc0c38d1 | 2734 | |
cffae437 SR |
2735 | if (cnt >= sizeof(buf)) |
2736 | return -EINVAL; | |
bc0c38d1 SR |
2737 | |
2738 | if (copy_from_user(&buf, ubuf, cnt)) | |
2739 | return -EFAULT; | |
2740 | ||
2741 | buf[cnt] = 0; | |
2742 | ||
c6caeeb1 SR |
2743 | ret = strict_strtoul(buf, 10, &val); |
2744 | if (ret < 0) | |
2745 | return ret; | |
bc0c38d1 SR |
2746 | |
2747 | *ptr = val * 1000; | |
2748 | ||
2749 | return cnt; | |
2750 | } | |
2751 | ||
b3806b43 SR |
2752 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2753 | { | |
b04cc6b1 | 2754 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2755 | struct trace_iterator *iter; |
b04cc6b1 | 2756 | int ret = 0; |
b3806b43 SR |
2757 | |
2758 | if (tracing_disabled) | |
2759 | return -ENODEV; | |
2760 | ||
b04cc6b1 FW |
2761 | mutex_lock(&trace_types_lock); |
2762 | ||
2763 | /* We only allow one reader per cpu */ | |
2764 | if (cpu_file == TRACE_PIPE_ALL_CPU) { | |
2765 | if (!cpumask_empty(tracing_reader_cpumask)) { | |
2766 | ret = -EBUSY; | |
2767 | goto out; | |
2768 | } | |
2769 | cpumask_setall(tracing_reader_cpumask); | |
2770 | } else { | |
2771 | if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask)) | |
2772 | cpumask_set_cpu(cpu_file, tracing_reader_cpumask); | |
2773 | else { | |
2774 | ret = -EBUSY; | |
2775 | goto out; | |
2776 | } | |
b3806b43 SR |
2777 | } |
2778 | ||
2779 | /* create a buffer to store the information to pass to userspace */ | |
2780 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2781 | if (!iter) { |
2782 | ret = -ENOMEM; | |
2783 | goto out; | |
2784 | } | |
b3806b43 | 2785 | |
d7350c3f FW |
2786 | /* |
2787 | * We make a copy of the current tracer to avoid concurrent | |
2788 | * changes on it while we are reading. | |
2789 | */ | |
2790 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
2791 | if (!iter->trace) { | |
2792 | ret = -ENOMEM; | |
2793 | goto fail; | |
2794 | } | |
2795 | if (current_trace) | |
2796 | *iter->trace = *current_trace; | |
2797 | ||
4462344e | 2798 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 2799 | ret = -ENOMEM; |
d7350c3f | 2800 | goto fail; |
4462344e RR |
2801 | } |
2802 | ||
a309720c | 2803 | /* trace pipe does not show start of buffer */ |
4462344e | 2804 | cpumask_setall(iter->started); |
a309720c | 2805 | |
b04cc6b1 | 2806 | iter->cpu_file = cpu_file; |
b3806b43 | 2807 | iter->tr = &global_trace; |
d7350c3f | 2808 | mutex_init(&iter->mutex); |
b3806b43 SR |
2809 | filp->private_data = iter; |
2810 | ||
107bad8b SR |
2811 | if (iter->trace->pipe_open) |
2812 | iter->trace->pipe_open(iter); | |
107bad8b | 2813 | |
b04cc6b1 FW |
2814 | out: |
2815 | mutex_unlock(&trace_types_lock); | |
2816 | return ret; | |
d7350c3f FW |
2817 | |
2818 | fail: | |
2819 | kfree(iter->trace); | |
2820 | kfree(iter); | |
2821 | mutex_unlock(&trace_types_lock); | |
2822 | return ret; | |
b3806b43 SR |
2823 | } |
2824 | ||
2825 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2826 | { | |
2827 | struct trace_iterator *iter = file->private_data; | |
2828 | ||
b04cc6b1 FW |
2829 | mutex_lock(&trace_types_lock); |
2830 | ||
2831 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) | |
2832 | cpumask_clear(tracing_reader_cpumask); | |
2833 | else | |
2834 | cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); | |
2835 | ||
2836 | mutex_unlock(&trace_types_lock); | |
2837 | ||
4462344e | 2838 | free_cpumask_var(iter->started); |
d7350c3f FW |
2839 | mutex_destroy(&iter->mutex); |
2840 | kfree(iter->trace); | |
b3806b43 | 2841 | kfree(iter); |
b3806b43 SR |
2842 | |
2843 | return 0; | |
2844 | } | |
2845 | ||
2a2cc8f7 SSP |
2846 | static unsigned int |
2847 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2848 | { | |
2849 | struct trace_iterator *iter = filp->private_data; | |
2850 | ||
2851 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2852 | /* | |
2853 | * Always select as readable when in blocking mode | |
2854 | */ | |
2855 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2856 | } else { |
2a2cc8f7 SSP |
2857 | if (!trace_empty(iter)) |
2858 | return POLLIN | POLLRDNORM; | |
2859 | poll_wait(filp, &trace_wait, poll_table); | |
2860 | if (!trace_empty(iter)) | |
2861 | return POLLIN | POLLRDNORM; | |
2862 | ||
2863 | return 0; | |
2864 | } | |
2865 | } | |
2866 | ||
6eaaa5d5 FW |
2867 | |
2868 | void default_wait_pipe(struct trace_iterator *iter) | |
2869 | { | |
2870 | DEFINE_WAIT(wait); | |
2871 | ||
2872 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
2873 | ||
2874 | if (trace_empty(iter)) | |
2875 | schedule(); | |
2876 | ||
2877 | finish_wait(&trace_wait, &wait); | |
2878 | } | |
2879 | ||
2880 | /* | |
2881 | * This is a make-shift waitqueue. | |
2882 | * A tracer might use this callback on some rare cases: | |
2883 | * | |
2884 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
2885 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
2886 | * 2) the function tracers, trace all functions, we don't want | |
2887 | * the overhead of calling wake_up and friends | |
2888 | * (and tracing them too) | |
2889 | * | |
2890 | * Anyway, this is really very primitive wakeup. | |
2891 | */ | |
2892 | void poll_wait_pipe(struct trace_iterator *iter) | |
2893 | { | |
2894 | set_current_state(TASK_INTERRUPTIBLE); | |
2895 | /* sleep for 100 msecs, and try again. */ | |
2896 | schedule_timeout(HZ / 10); | |
2897 | } | |
2898 | ||
ff98781b EGM |
2899 | /* Must be called with trace_types_lock mutex held. */ |
2900 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
2901 | { |
2902 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 2903 | |
b3806b43 | 2904 | while (trace_empty(iter)) { |
2dc8f095 | 2905 | |
107bad8b | 2906 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 2907 | return -EAGAIN; |
107bad8b | 2908 | } |
2dc8f095 | 2909 | |
d7350c3f | 2910 | mutex_unlock(&iter->mutex); |
107bad8b | 2911 | |
6eaaa5d5 | 2912 | iter->trace->wait_pipe(iter); |
b3806b43 | 2913 | |
d7350c3f | 2914 | mutex_lock(&iter->mutex); |
107bad8b | 2915 | |
6eaaa5d5 | 2916 | if (signal_pending(current)) |
ff98781b | 2917 | return -EINTR; |
b3806b43 SR |
2918 | |
2919 | /* | |
2920 | * We block until we read something and tracing is disabled. | |
2921 | * We still block if tracing is disabled, but we have never | |
2922 | * read anything. This allows a user to cat this file, and | |
2923 | * then enable tracing. But after we have read something, | |
2924 | * we give an EOF when tracing is again disabled. | |
2925 | * | |
2926 | * iter->pos will be 0 if we haven't read anything. | |
2927 | */ | |
2928 | if (!tracer_enabled && iter->pos) | |
2929 | break; | |
b3806b43 SR |
2930 | } |
2931 | ||
ff98781b EGM |
2932 | return 1; |
2933 | } | |
2934 | ||
2935 | /* | |
2936 | * Consumer reader. | |
2937 | */ | |
2938 | static ssize_t | |
2939 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2940 | size_t cnt, loff_t *ppos) | |
2941 | { | |
2942 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 2943 | static struct tracer *old_tracer; |
ff98781b EGM |
2944 | ssize_t sret; |
2945 | ||
2946 | /* return any leftover data */ | |
2947 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
2948 | if (sret != -EBUSY) | |
2949 | return sret; | |
2950 | ||
f9520750 | 2951 | trace_seq_init(&iter->seq); |
ff98781b | 2952 | |
d7350c3f | 2953 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 2954 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2955 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2956 | old_tracer = current_trace; | |
2957 | *iter->trace = *current_trace; | |
2958 | } | |
2959 | mutex_unlock(&trace_types_lock); | |
2960 | ||
2961 | /* | |
2962 | * Avoid more than one consumer on a single file descriptor | |
2963 | * This is just a matter of traces coherency, the ring buffer itself | |
2964 | * is protected. | |
2965 | */ | |
2966 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
2967 | if (iter->trace->read) { |
2968 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
2969 | if (sret) | |
2970 | goto out; | |
2971 | } | |
2972 | ||
2973 | waitagain: | |
2974 | sret = tracing_wait_pipe(filp); | |
2975 | if (sret <= 0) | |
2976 | goto out; | |
2977 | ||
b3806b43 | 2978 | /* stop when tracing is finished */ |
ff98781b EGM |
2979 | if (trace_empty(iter)) { |
2980 | sret = 0; | |
107bad8b | 2981 | goto out; |
ff98781b | 2982 | } |
b3806b43 SR |
2983 | |
2984 | if (cnt >= PAGE_SIZE) | |
2985 | cnt = PAGE_SIZE - 1; | |
2986 | ||
53d0aa77 | 2987 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
2988 | memset(&iter->seq, 0, |
2989 | sizeof(struct trace_iterator) - | |
2990 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 2991 | iter->pos = -1; |
b3806b43 | 2992 | |
088b1e42 | 2993 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 2994 | enum print_line_t ret; |
088b1e42 SR |
2995 | int len = iter->seq.len; |
2996 | ||
f9896bf3 | 2997 | ret = print_trace_line(iter); |
2c4f035f | 2998 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
2999 | /* don't print partial lines */ |
3000 | iter->seq.len = len; | |
b3806b43 | 3001 | break; |
088b1e42 | 3002 | } |
b91facc3 FW |
3003 | if (ret != TRACE_TYPE_NO_CONSUME) |
3004 | trace_consume(iter); | |
b3806b43 SR |
3005 | |
3006 | if (iter->seq.len >= cnt) | |
3007 | break; | |
b3806b43 SR |
3008 | } |
3009 | ||
b3806b43 | 3010 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3011 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3012 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3013 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3014 | |
3015 | /* | |
3016 | * If there was nothing to send to user, inspite of consuming trace | |
3017 | * entries, go back to wait for more entries. | |
3018 | */ | |
6c6c2796 | 3019 | if (sret == -EBUSY) |
9ff4b974 | 3020 | goto waitagain; |
b3806b43 | 3021 | |
107bad8b | 3022 | out: |
d7350c3f | 3023 | mutex_unlock(&iter->mutex); |
107bad8b | 3024 | |
6c6c2796 | 3025 | return sret; |
b3806b43 SR |
3026 | } |
3027 | ||
3c56819b EGM |
3028 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3029 | struct pipe_buffer *buf) | |
3030 | { | |
3031 | __free_page(buf->page); | |
3032 | } | |
3033 | ||
3034 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3035 | unsigned int idx) | |
3036 | { | |
3037 | __free_page(spd->pages[idx]); | |
3038 | } | |
3039 | ||
3040 | static struct pipe_buf_operations tracing_pipe_buf_ops = { | |
34cd4998 SR |
3041 | .can_merge = 0, |
3042 | .map = generic_pipe_buf_map, | |
3043 | .unmap = generic_pipe_buf_unmap, | |
3044 | .confirm = generic_pipe_buf_confirm, | |
3045 | .release = tracing_pipe_buf_release, | |
3046 | .steal = generic_pipe_buf_steal, | |
3047 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3048 | }; |
3049 | ||
34cd4998 | 3050 | static size_t |
fa7c7f6e | 3051 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3052 | { |
3053 | size_t count; | |
3054 | int ret; | |
3055 | ||
3056 | /* Seq buffer is page-sized, exactly what we need. */ | |
3057 | for (;;) { | |
3058 | count = iter->seq.len; | |
3059 | ret = print_trace_line(iter); | |
3060 | count = iter->seq.len - count; | |
3061 | if (rem < count) { | |
3062 | rem = 0; | |
3063 | iter->seq.len -= count; | |
3064 | break; | |
3065 | } | |
3066 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3067 | iter->seq.len -= count; | |
3068 | break; | |
3069 | } | |
3070 | ||
3071 | trace_consume(iter); | |
3072 | rem -= count; | |
3073 | if (!find_next_entry_inc(iter)) { | |
3074 | rem = 0; | |
3075 | iter->ent = NULL; | |
3076 | break; | |
3077 | } | |
3078 | } | |
3079 | ||
3080 | return rem; | |
3081 | } | |
3082 | ||
3c56819b EGM |
3083 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3084 | loff_t *ppos, | |
3085 | struct pipe_inode_info *pipe, | |
3086 | size_t len, | |
3087 | unsigned int flags) | |
3088 | { | |
3089 | struct page *pages[PIPE_BUFFERS]; | |
3090 | struct partial_page partial[PIPE_BUFFERS]; | |
3091 | struct trace_iterator *iter = filp->private_data; | |
3092 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
3093 | .pages = pages, |
3094 | .partial = partial, | |
3095 | .nr_pages = 0, /* This gets updated below. */ | |
3096 | .flags = flags, | |
3097 | .ops = &tracing_pipe_buf_ops, | |
3098 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3099 | }; |
d7350c3f | 3100 | static struct tracer *old_tracer; |
3c56819b | 3101 | ssize_t ret; |
34cd4998 | 3102 | size_t rem; |
3c56819b EGM |
3103 | unsigned int i; |
3104 | ||
d7350c3f | 3105 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3106 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3107 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3108 | old_tracer = current_trace; | |
3109 | *iter->trace = *current_trace; | |
3110 | } | |
3111 | mutex_unlock(&trace_types_lock); | |
3112 | ||
3113 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3114 | |
3115 | if (iter->trace->splice_read) { | |
3116 | ret = iter->trace->splice_read(iter, filp, | |
3117 | ppos, pipe, len, flags); | |
3118 | if (ret) | |
34cd4998 | 3119 | goto out_err; |
3c56819b EGM |
3120 | } |
3121 | ||
3122 | ret = tracing_wait_pipe(filp); | |
3123 | if (ret <= 0) | |
34cd4998 | 3124 | goto out_err; |
3c56819b EGM |
3125 | |
3126 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
3127 | ret = -EFAULT; | |
34cd4998 | 3128 | goto out_err; |
3c56819b EGM |
3129 | } |
3130 | ||
3131 | /* Fill as many pages as possible. */ | |
3132 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
3133 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
3134 | if (!pages[i]) |
3135 | break; | |
3c56819b | 3136 | |
fa7c7f6e | 3137 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3138 | |
3139 | /* Copy the data into the page, so we can start over. */ | |
3140 | ret = trace_seq_to_buffer(&iter->seq, | |
3141 | page_address(pages[i]), | |
3142 | iter->seq.len); | |
3143 | if (ret < 0) { | |
3144 | __free_page(pages[i]); | |
3145 | break; | |
3146 | } | |
3147 | partial[i].offset = 0; | |
3148 | partial[i].len = iter->seq.len; | |
3149 | ||
f9520750 | 3150 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3151 | } |
3152 | ||
d7350c3f | 3153 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3154 | |
3155 | spd.nr_pages = i; | |
3156 | ||
3157 | return splice_to_pipe(pipe, &spd); | |
3158 | ||
34cd4998 | 3159 | out_err: |
d7350c3f | 3160 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3161 | |
3162 | return ret; | |
3163 | } | |
3164 | ||
a98a3c3f SR |
3165 | static ssize_t |
3166 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3167 | size_t cnt, loff_t *ppos) | |
3168 | { | |
3169 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3170 | char buf[96]; |
a98a3c3f SR |
3171 | int r; |
3172 | ||
db526ca3 SR |
3173 | mutex_lock(&trace_types_lock); |
3174 | if (!ring_buffer_expanded) | |
3175 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3176 | tr->entries >> 10, | |
3177 | trace_buf_size >> 10); | |
3178 | else | |
3179 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3180 | mutex_unlock(&trace_types_lock); | |
3181 | ||
a98a3c3f SR |
3182 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3183 | } | |
3184 | ||
3185 | static ssize_t | |
3186 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3187 | size_t cnt, loff_t *ppos) | |
3188 | { | |
3189 | unsigned long val; | |
3190 | char buf[64]; | |
bf5e6519 | 3191 | int ret, cpu; |
a98a3c3f | 3192 | |
cffae437 SR |
3193 | if (cnt >= sizeof(buf)) |
3194 | return -EINVAL; | |
a98a3c3f SR |
3195 | |
3196 | if (copy_from_user(&buf, ubuf, cnt)) | |
3197 | return -EFAULT; | |
3198 | ||
3199 | buf[cnt] = 0; | |
3200 | ||
c6caeeb1 SR |
3201 | ret = strict_strtoul(buf, 10, &val); |
3202 | if (ret < 0) | |
3203 | return ret; | |
a98a3c3f SR |
3204 | |
3205 | /* must have at least 1 entry */ | |
3206 | if (!val) | |
3207 | return -EINVAL; | |
3208 | ||
3209 | mutex_lock(&trace_types_lock); | |
3210 | ||
c76f0694 | 3211 | tracing_stop(); |
a98a3c3f | 3212 | |
bf5e6519 SR |
3213 | /* disable all cpu buffers */ |
3214 | for_each_tracing_cpu(cpu) { | |
3215 | if (global_trace.data[cpu]) | |
3216 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3217 | if (max_tr.data[cpu]) | |
3218 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3219 | } | |
3220 | ||
1696b2b0 SR |
3221 | /* value is in KB */ |
3222 | val <<= 10; | |
3223 | ||
3928a8a2 | 3224 | if (val != global_trace.entries) { |
73c5162a | 3225 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3226 | if (ret < 0) { |
3227 | cnt = ret; | |
3eefae99 SR |
3228 | goto out; |
3229 | } | |
a98a3c3f SR |
3230 | } |
3231 | ||
3232 | filp->f_pos += cnt; | |
3233 | ||
19384c03 SR |
3234 | /* If check pages failed, return ENOMEM */ |
3235 | if (tracing_disabled) | |
3236 | cnt = -ENOMEM; | |
a98a3c3f | 3237 | out: |
bf5e6519 SR |
3238 | for_each_tracing_cpu(cpu) { |
3239 | if (global_trace.data[cpu]) | |
3240 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3241 | if (max_tr.data[cpu]) | |
3242 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3243 | } | |
3244 | ||
c76f0694 | 3245 | tracing_start(); |
a98a3c3f SR |
3246 | max_tr.entries = global_trace.entries; |
3247 | mutex_unlock(&trace_types_lock); | |
3248 | ||
3249 | return cnt; | |
3250 | } | |
3251 | ||
5bf9a1ee PP |
3252 | static int mark_printk(const char *fmt, ...) |
3253 | { | |
3254 | int ret; | |
3255 | va_list args; | |
3256 | va_start(args, fmt); | |
40ce74f1 | 3257 | ret = trace_vprintk(0, fmt, args); |
5bf9a1ee PP |
3258 | va_end(args); |
3259 | return ret; | |
3260 | } | |
3261 | ||
3262 | static ssize_t | |
3263 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3264 | size_t cnt, loff_t *fpos) | |
3265 | { | |
3266 | char *buf; | |
3267 | char *end; | |
5bf9a1ee | 3268 | |
c76f0694 | 3269 | if (tracing_disabled) |
5bf9a1ee PP |
3270 | return -EINVAL; |
3271 | ||
3272 | if (cnt > TRACE_BUF_SIZE) | |
3273 | cnt = TRACE_BUF_SIZE; | |
3274 | ||
3275 | buf = kmalloc(cnt + 1, GFP_KERNEL); | |
3276 | if (buf == NULL) | |
3277 | return -ENOMEM; | |
3278 | ||
3279 | if (copy_from_user(buf, ubuf, cnt)) { | |
3280 | kfree(buf); | |
3281 | return -EFAULT; | |
3282 | } | |
3283 | ||
3284 | /* Cut from the first nil or newline. */ | |
3285 | buf[cnt] = '\0'; | |
3286 | end = strchr(buf, '\n'); | |
3287 | if (end) | |
3288 | *end = '\0'; | |
3289 | ||
3290 | cnt = mark_printk("%s\n", buf); | |
3291 | kfree(buf); | |
3292 | *fpos += cnt; | |
3293 | ||
3294 | return cnt; | |
3295 | } | |
3296 | ||
5e2336a0 | 3297 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3298 | .open = tracing_open_generic, |
3299 | .read = tracing_max_lat_read, | |
3300 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
3301 | }; |
3302 | ||
5e2336a0 | 3303 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3304 | .open = tracing_open_generic, |
3305 | .read = tracing_ctrl_read, | |
3306 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
3307 | }; |
3308 | ||
5e2336a0 | 3309 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3310 | .open = tracing_open_generic, |
3311 | .read = tracing_set_trace_read, | |
3312 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
3313 | }; |
3314 | ||
5e2336a0 | 3315 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3316 | .open = tracing_open_pipe, |
2a2cc8f7 | 3317 | .poll = tracing_poll_pipe, |
4bf39a94 | 3318 | .read = tracing_read_pipe, |
3c56819b | 3319 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3320 | .release = tracing_release_pipe, |
b3806b43 SR |
3321 | }; |
3322 | ||
5e2336a0 | 3323 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3324 | .open = tracing_open_generic, |
3325 | .read = tracing_entries_read, | |
3326 | .write = tracing_entries_write, | |
3327 | }; | |
3328 | ||
5e2336a0 | 3329 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3330 | .open = tracing_open_generic, |
5bf9a1ee PP |
3331 | .write = tracing_mark_write, |
3332 | }; | |
3333 | ||
2cadf913 SR |
3334 | struct ftrace_buffer_info { |
3335 | struct trace_array *tr; | |
3336 | void *spare; | |
3337 | int cpu; | |
3338 | unsigned int read; | |
3339 | }; | |
3340 | ||
3341 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3342 | { | |
3343 | int cpu = (int)(long)inode->i_private; | |
3344 | struct ftrace_buffer_info *info; | |
3345 | ||
3346 | if (tracing_disabled) | |
3347 | return -ENODEV; | |
3348 | ||
3349 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3350 | if (!info) | |
3351 | return -ENOMEM; | |
3352 | ||
3353 | info->tr = &global_trace; | |
3354 | info->cpu = cpu; | |
ddd538f3 | 3355 | info->spare = NULL; |
2cadf913 SR |
3356 | /* Force reading ring buffer for first read */ |
3357 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3358 | |
3359 | filp->private_data = info; | |
3360 | ||
d1e7e02f | 3361 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3362 | } |
3363 | ||
3364 | static ssize_t | |
3365 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3366 | size_t count, loff_t *ppos) | |
3367 | { | |
3368 | struct ftrace_buffer_info *info = filp->private_data; | |
3369 | unsigned int pos; | |
3370 | ssize_t ret; | |
3371 | size_t size; | |
3372 | ||
2dc5d12b SR |
3373 | if (!count) |
3374 | return 0; | |
3375 | ||
ddd538f3 LJ |
3376 | if (!info->spare) |
3377 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3378 | if (!info->spare) | |
3379 | return -ENOMEM; | |
3380 | ||
2cadf913 SR |
3381 | /* Do we have previous read data to read? */ |
3382 | if (info->read < PAGE_SIZE) | |
3383 | goto read; | |
3384 | ||
3385 | info->read = 0; | |
3386 | ||
3387 | ret = ring_buffer_read_page(info->tr->buffer, | |
3388 | &info->spare, | |
3389 | count, | |
3390 | info->cpu, 0); | |
3391 | if (ret < 0) | |
3392 | return 0; | |
3393 | ||
3394 | pos = ring_buffer_page_len(info->spare); | |
3395 | ||
3396 | if (pos < PAGE_SIZE) | |
3397 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3398 | ||
3399 | read: | |
3400 | size = PAGE_SIZE - info->read; | |
3401 | if (size > count) | |
3402 | size = count; | |
3403 | ||
3404 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3405 | if (ret == size) |
2cadf913 | 3406 | return -EFAULT; |
2dc5d12b SR |
3407 | size -= ret; |
3408 | ||
2cadf913 SR |
3409 | *ppos += size; |
3410 | info->read += size; | |
3411 | ||
3412 | return size; | |
3413 | } | |
3414 | ||
3415 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3416 | { | |
3417 | struct ftrace_buffer_info *info = file->private_data; | |
3418 | ||
ddd538f3 LJ |
3419 | if (info->spare) |
3420 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3421 | kfree(info); |
3422 | ||
3423 | return 0; | |
3424 | } | |
3425 | ||
3426 | struct buffer_ref { | |
3427 | struct ring_buffer *buffer; | |
3428 | void *page; | |
3429 | int ref; | |
3430 | }; | |
3431 | ||
3432 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3433 | struct pipe_buffer *buf) | |
3434 | { | |
3435 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3436 | ||
3437 | if (--ref->ref) | |
3438 | return; | |
3439 | ||
3440 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3441 | kfree(ref); | |
3442 | buf->private = 0; | |
3443 | } | |
3444 | ||
3445 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3446 | struct pipe_buffer *buf) | |
3447 | { | |
3448 | return 1; | |
3449 | } | |
3450 | ||
3451 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3452 | struct pipe_buffer *buf) | |
3453 | { | |
3454 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3455 | ||
3456 | ref->ref++; | |
3457 | } | |
3458 | ||
3459 | /* Pipe buffer operations for a buffer. */ | |
3460 | static struct pipe_buf_operations buffer_pipe_buf_ops = { | |
3461 | .can_merge = 0, | |
3462 | .map = generic_pipe_buf_map, | |
3463 | .unmap = generic_pipe_buf_unmap, | |
3464 | .confirm = generic_pipe_buf_confirm, | |
3465 | .release = buffer_pipe_buf_release, | |
3466 | .steal = buffer_pipe_buf_steal, | |
3467 | .get = buffer_pipe_buf_get, | |
3468 | }; | |
3469 | ||
3470 | /* | |
3471 | * Callback from splice_to_pipe(), if we need to release some pages | |
3472 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3473 | */ | |
3474 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3475 | { | |
3476 | struct buffer_ref *ref = | |
3477 | (struct buffer_ref *)spd->partial[i].private; | |
3478 | ||
3479 | if (--ref->ref) | |
3480 | return; | |
3481 | ||
3482 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3483 | kfree(ref); | |
3484 | spd->partial[i].private = 0; | |
3485 | } | |
3486 | ||
3487 | static ssize_t | |
3488 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3489 | struct pipe_inode_info *pipe, size_t len, | |
3490 | unsigned int flags) | |
3491 | { | |
3492 | struct ftrace_buffer_info *info = file->private_data; | |
3493 | struct partial_page partial[PIPE_BUFFERS]; | |
3494 | struct page *pages[PIPE_BUFFERS]; | |
3495 | struct splice_pipe_desc spd = { | |
3496 | .pages = pages, | |
3497 | .partial = partial, | |
3498 | .flags = flags, | |
3499 | .ops = &buffer_pipe_buf_ops, | |
3500 | .spd_release = buffer_spd_release, | |
3501 | }; | |
3502 | struct buffer_ref *ref; | |
3503 | int size, i; | |
3504 | size_t ret; | |
3505 | ||
93cfb3c9 LJ |
3506 | if (*ppos & (PAGE_SIZE - 1)) { |
3507 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
3508 | return -EINVAL; | |
3509 | } | |
2cadf913 | 3510 | |
93cfb3c9 LJ |
3511 | if (len & (PAGE_SIZE - 1)) { |
3512 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
3513 | if (len < PAGE_SIZE) | |
3514 | return -EINVAL; | |
3515 | len &= PAGE_MASK; | |
3516 | } | |
2cadf913 | 3517 | |
93cfb3c9 | 3518 | for (i = 0; i < PIPE_BUFFERS && len; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
3519 | struct page *page; |
3520 | int r; | |
3521 | ||
3522 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3523 | if (!ref) | |
3524 | break; | |
3525 | ||
3526 | ref->buffer = info->tr->buffer; | |
3527 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3528 | if (!ref->page) { | |
3529 | kfree(ref); | |
3530 | break; | |
3531 | } | |
3532 | ||
3533 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
3534 | len, info->cpu, 0); | |
3535 | if (r < 0) { | |
3536 | ring_buffer_free_read_page(ref->buffer, | |
3537 | ref->page); | |
3538 | kfree(ref); | |
3539 | break; | |
3540 | } | |
3541 | ||
3542 | /* | |
3543 | * zero out any left over data, this is going to | |
3544 | * user land. | |
3545 | */ | |
3546 | size = ring_buffer_page_len(ref->page); | |
3547 | if (size < PAGE_SIZE) | |
3548 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3549 | ||
3550 | page = virt_to_page(ref->page); | |
3551 | ||
3552 | spd.pages[i] = page; | |
3553 | spd.partial[i].len = PAGE_SIZE; | |
3554 | spd.partial[i].offset = 0; | |
3555 | spd.partial[i].private = (unsigned long)ref; | |
3556 | spd.nr_pages++; | |
93cfb3c9 | 3557 | *ppos += PAGE_SIZE; |
2cadf913 SR |
3558 | } |
3559 | ||
3560 | spd.nr_pages = i; | |
3561 | ||
3562 | /* did we read anything? */ | |
3563 | if (!spd.nr_pages) { | |
3564 | if (flags & SPLICE_F_NONBLOCK) | |
3565 | ret = -EAGAIN; | |
3566 | else | |
3567 | ret = 0; | |
3568 | /* TODO: block */ | |
3569 | return ret; | |
3570 | } | |
3571 | ||
3572 | ret = splice_to_pipe(pipe, &spd); | |
3573 | ||
3574 | return ret; | |
3575 | } | |
3576 | ||
3577 | static const struct file_operations tracing_buffers_fops = { | |
3578 | .open = tracing_buffers_open, | |
3579 | .read = tracing_buffers_read, | |
3580 | .release = tracing_buffers_release, | |
3581 | .splice_read = tracing_buffers_splice_read, | |
3582 | .llseek = no_llseek, | |
3583 | }; | |
3584 | ||
bc0c38d1 SR |
3585 | #ifdef CONFIG_DYNAMIC_FTRACE |
3586 | ||
b807c3d0 SR |
3587 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3588 | { | |
3589 | return 0; | |
3590 | } | |
3591 | ||
bc0c38d1 | 3592 | static ssize_t |
b807c3d0 | 3593 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3594 | size_t cnt, loff_t *ppos) |
3595 | { | |
a26a2a27 SR |
3596 | static char ftrace_dyn_info_buffer[1024]; |
3597 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3598 | unsigned long *p = filp->private_data; |
b807c3d0 | 3599 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3600 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3601 | int r; |
3602 | ||
b807c3d0 SR |
3603 | mutex_lock(&dyn_info_mutex); |
3604 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3605 | |
a26a2a27 | 3606 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3607 | buf[r++] = '\n'; |
3608 | ||
3609 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3610 | ||
3611 | mutex_unlock(&dyn_info_mutex); | |
3612 | ||
3613 | return r; | |
bc0c38d1 SR |
3614 | } |
3615 | ||
5e2336a0 | 3616 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3617 | .open = tracing_open_generic, |
b807c3d0 | 3618 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3619 | }; |
3620 | #endif | |
3621 | ||
3622 | static struct dentry *d_tracer; | |
3623 | ||
3624 | struct dentry *tracing_init_dentry(void) | |
3625 | { | |
3626 | static int once; | |
3627 | ||
3628 | if (d_tracer) | |
3629 | return d_tracer; | |
3630 | ||
3e1f60b8 FW |
3631 | if (!debugfs_initialized()) |
3632 | return NULL; | |
3633 | ||
bc0c38d1 SR |
3634 | d_tracer = debugfs_create_dir("tracing", NULL); |
3635 | ||
3636 | if (!d_tracer && !once) { | |
3637 | once = 1; | |
3638 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3639 | return NULL; | |
3640 | } | |
3641 | ||
3642 | return d_tracer; | |
3643 | } | |
3644 | ||
b04cc6b1 FW |
3645 | static struct dentry *d_percpu; |
3646 | ||
3647 | struct dentry *tracing_dentry_percpu(void) | |
3648 | { | |
3649 | static int once; | |
3650 | struct dentry *d_tracer; | |
3651 | ||
3652 | if (d_percpu) | |
3653 | return d_percpu; | |
3654 | ||
3655 | d_tracer = tracing_init_dentry(); | |
3656 | ||
3657 | if (!d_tracer) | |
3658 | return NULL; | |
3659 | ||
3660 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
3661 | ||
3662 | if (!d_percpu && !once) { | |
3663 | once = 1; | |
3664 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
3665 | return NULL; | |
3666 | } | |
3667 | ||
3668 | return d_percpu; | |
3669 | } | |
3670 | ||
3671 | static void tracing_init_debugfs_percpu(long cpu) | |
3672 | { | |
3673 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 3674 | struct dentry *d_cpu; |
8656e7a2 FW |
3675 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ |
3676 | char cpu_dir[7]; | |
b04cc6b1 FW |
3677 | |
3678 | if (cpu > 999 || cpu < 0) | |
3679 | return; | |
3680 | ||
8656e7a2 FW |
3681 | sprintf(cpu_dir, "cpu%ld", cpu); |
3682 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
3683 | if (!d_cpu) { | |
3684 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
3685 | return; | |
3686 | } | |
b04cc6b1 | 3687 | |
8656e7a2 | 3688 | /* per cpu trace_pipe */ |
5452af66 FW |
3689 | trace_create_file("trace_pipe", 0444, d_cpu, |
3690 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
3691 | |
3692 | /* per cpu trace */ | |
5452af66 FW |
3693 | trace_create_file("trace", 0644, d_cpu, |
3694 | (void *) cpu, &tracing_fops); | |
7f96f93f | 3695 | |
5452af66 FW |
3696 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
3697 | (void *) cpu, &tracing_buffers_fops); | |
b04cc6b1 FW |
3698 | } |
3699 | ||
60a11774 SR |
3700 | #ifdef CONFIG_FTRACE_SELFTEST |
3701 | /* Let selftest have access to static functions in this file */ | |
3702 | #include "trace_selftest.c" | |
3703 | #endif | |
3704 | ||
577b785f SR |
3705 | struct trace_option_dentry { |
3706 | struct tracer_opt *opt; | |
3707 | struct tracer_flags *flags; | |
3708 | struct dentry *entry; | |
3709 | }; | |
3710 | ||
3711 | static ssize_t | |
3712 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3713 | loff_t *ppos) | |
3714 | { | |
3715 | struct trace_option_dentry *topt = filp->private_data; | |
3716 | char *buf; | |
3717 | ||
3718 | if (topt->flags->val & topt->opt->bit) | |
3719 | buf = "1\n"; | |
3720 | else | |
3721 | buf = "0\n"; | |
3722 | ||
3723 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3724 | } | |
3725 | ||
3726 | static ssize_t | |
3727 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3728 | loff_t *ppos) | |
3729 | { | |
3730 | struct trace_option_dentry *topt = filp->private_data; | |
3731 | unsigned long val; | |
3732 | char buf[64]; | |
3733 | int ret; | |
3734 | ||
3735 | if (cnt >= sizeof(buf)) | |
3736 | return -EINVAL; | |
3737 | ||
3738 | if (copy_from_user(&buf, ubuf, cnt)) | |
3739 | return -EFAULT; | |
3740 | ||
3741 | buf[cnt] = 0; | |
3742 | ||
3743 | ret = strict_strtoul(buf, 10, &val); | |
3744 | if (ret < 0) | |
3745 | return ret; | |
3746 | ||
3747 | ret = 0; | |
3748 | switch (val) { | |
3749 | case 0: | |
3750 | /* do nothing if already cleared */ | |
3751 | if (!(topt->flags->val & topt->opt->bit)) | |
3752 | break; | |
3753 | ||
3754 | mutex_lock(&trace_types_lock); | |
3755 | if (current_trace->set_flag) | |
3756 | ret = current_trace->set_flag(topt->flags->val, | |
3757 | topt->opt->bit, 0); | |
3758 | mutex_unlock(&trace_types_lock); | |
3759 | if (ret) | |
3760 | return ret; | |
3761 | topt->flags->val &= ~topt->opt->bit; | |
3762 | break; | |
3763 | case 1: | |
3764 | /* do nothing if already set */ | |
3765 | if (topt->flags->val & topt->opt->bit) | |
3766 | break; | |
3767 | ||
3768 | mutex_lock(&trace_types_lock); | |
3769 | if (current_trace->set_flag) | |
3770 | ret = current_trace->set_flag(topt->flags->val, | |
3771 | topt->opt->bit, 1); | |
3772 | mutex_unlock(&trace_types_lock); | |
3773 | if (ret) | |
3774 | return ret; | |
3775 | topt->flags->val |= topt->opt->bit; | |
3776 | break; | |
3777 | ||
3778 | default: | |
3779 | return -EINVAL; | |
3780 | } | |
3781 | ||
3782 | *ppos += cnt; | |
3783 | ||
3784 | return cnt; | |
3785 | } | |
3786 | ||
3787 | ||
3788 | static const struct file_operations trace_options_fops = { | |
3789 | .open = tracing_open_generic, | |
3790 | .read = trace_options_read, | |
3791 | .write = trace_options_write, | |
3792 | }; | |
3793 | ||
a8259075 SR |
3794 | static ssize_t |
3795 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3796 | loff_t *ppos) | |
3797 | { | |
3798 | long index = (long)filp->private_data; | |
3799 | char *buf; | |
3800 | ||
3801 | if (trace_flags & (1 << index)) | |
3802 | buf = "1\n"; | |
3803 | else | |
3804 | buf = "0\n"; | |
3805 | ||
3806 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3807 | } | |
3808 | ||
3809 | static ssize_t | |
3810 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3811 | loff_t *ppos) | |
3812 | { | |
3813 | long index = (long)filp->private_data; | |
3814 | char buf[64]; | |
3815 | unsigned long val; | |
3816 | int ret; | |
3817 | ||
3818 | if (cnt >= sizeof(buf)) | |
3819 | return -EINVAL; | |
3820 | ||
3821 | if (copy_from_user(&buf, ubuf, cnt)) | |
3822 | return -EFAULT; | |
3823 | ||
3824 | buf[cnt] = 0; | |
3825 | ||
3826 | ret = strict_strtoul(buf, 10, &val); | |
3827 | if (ret < 0) | |
3828 | return ret; | |
3829 | ||
3830 | switch (val) { | |
3831 | case 0: | |
3832 | trace_flags &= ~(1 << index); | |
3833 | break; | |
3834 | case 1: | |
3835 | trace_flags |= 1 << index; | |
3836 | break; | |
3837 | ||
3838 | default: | |
3839 | return -EINVAL; | |
3840 | } | |
3841 | ||
3842 | *ppos += cnt; | |
3843 | ||
3844 | return cnt; | |
3845 | } | |
3846 | ||
a8259075 SR |
3847 | static const struct file_operations trace_options_core_fops = { |
3848 | .open = tracing_open_generic, | |
3849 | .read = trace_options_core_read, | |
3850 | .write = trace_options_core_write, | |
3851 | }; | |
3852 | ||
5452af66 FW |
3853 | struct dentry *trace_create_file(const char *name, |
3854 | mode_t mode, | |
3855 | struct dentry *parent, | |
3856 | void *data, | |
3857 | const struct file_operations *fops) | |
3858 | { | |
3859 | struct dentry *ret; | |
3860 | ||
3861 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
3862 | if (!ret) | |
3863 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
3864 | ||
3865 | return ret; | |
3866 | } | |
3867 | ||
3868 | ||
a8259075 SR |
3869 | static struct dentry *trace_options_init_dentry(void) |
3870 | { | |
3871 | struct dentry *d_tracer; | |
3872 | static struct dentry *t_options; | |
3873 | ||
3874 | if (t_options) | |
3875 | return t_options; | |
3876 | ||
3877 | d_tracer = tracing_init_dentry(); | |
3878 | if (!d_tracer) | |
3879 | return NULL; | |
3880 | ||
3881 | t_options = debugfs_create_dir("options", d_tracer); | |
3882 | if (!t_options) { | |
3883 | pr_warning("Could not create debugfs directory 'options'\n"); | |
3884 | return NULL; | |
3885 | } | |
3886 | ||
3887 | return t_options; | |
3888 | } | |
3889 | ||
577b785f SR |
3890 | static void |
3891 | create_trace_option_file(struct trace_option_dentry *topt, | |
3892 | struct tracer_flags *flags, | |
3893 | struct tracer_opt *opt) | |
3894 | { | |
3895 | struct dentry *t_options; | |
577b785f SR |
3896 | |
3897 | t_options = trace_options_init_dentry(); | |
3898 | if (!t_options) | |
3899 | return; | |
3900 | ||
3901 | topt->flags = flags; | |
3902 | topt->opt = opt; | |
3903 | ||
5452af66 | 3904 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
3905 | &trace_options_fops); |
3906 | ||
577b785f SR |
3907 | } |
3908 | ||
3909 | static struct trace_option_dentry * | |
3910 | create_trace_option_files(struct tracer *tracer) | |
3911 | { | |
3912 | struct trace_option_dentry *topts; | |
3913 | struct tracer_flags *flags; | |
3914 | struct tracer_opt *opts; | |
3915 | int cnt; | |
3916 | ||
3917 | if (!tracer) | |
3918 | return NULL; | |
3919 | ||
3920 | flags = tracer->flags; | |
3921 | ||
3922 | if (!flags || !flags->opts) | |
3923 | return NULL; | |
3924 | ||
3925 | opts = flags->opts; | |
3926 | ||
3927 | for (cnt = 0; opts[cnt].name; cnt++) | |
3928 | ; | |
3929 | ||
0cfe8245 | 3930 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
3931 | if (!topts) |
3932 | return NULL; | |
3933 | ||
3934 | for (cnt = 0; opts[cnt].name; cnt++) | |
3935 | create_trace_option_file(&topts[cnt], flags, | |
3936 | &opts[cnt]); | |
3937 | ||
3938 | return topts; | |
3939 | } | |
3940 | ||
3941 | static void | |
3942 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
3943 | { | |
3944 | int cnt; | |
3945 | ||
3946 | if (!topts) | |
3947 | return; | |
3948 | ||
3949 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
3950 | if (topts[cnt].entry) | |
3951 | debugfs_remove(topts[cnt].entry); | |
3952 | } | |
3953 | ||
3954 | kfree(topts); | |
3955 | } | |
3956 | ||
a8259075 SR |
3957 | static struct dentry * |
3958 | create_trace_option_core_file(const char *option, long index) | |
3959 | { | |
3960 | struct dentry *t_options; | |
a8259075 SR |
3961 | |
3962 | t_options = trace_options_init_dentry(); | |
3963 | if (!t_options) | |
3964 | return NULL; | |
3965 | ||
5452af66 | 3966 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 3967 | &trace_options_core_fops); |
a8259075 SR |
3968 | } |
3969 | ||
3970 | static __init void create_trace_options_dir(void) | |
3971 | { | |
3972 | struct dentry *t_options; | |
a8259075 SR |
3973 | int i; |
3974 | ||
3975 | t_options = trace_options_init_dentry(); | |
3976 | if (!t_options) | |
3977 | return; | |
3978 | ||
5452af66 FW |
3979 | for (i = 0; trace_options[i]; i++) |
3980 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
3981 | } |
3982 | ||
b5ad384e | 3983 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
3984 | { |
3985 | struct dentry *d_tracer; | |
b04cc6b1 | 3986 | int cpu; |
bc0c38d1 SR |
3987 | |
3988 | d_tracer = tracing_init_dentry(); | |
3989 | ||
5452af66 FW |
3990 | trace_create_file("tracing_enabled", 0644, d_tracer, |
3991 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 3992 | |
5452af66 FW |
3993 | trace_create_file("trace_options", 0644, d_tracer, |
3994 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 3995 | |
5452af66 FW |
3996 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
3997 | NULL, &tracing_cpumask_fops); | |
3998 | ||
3999 | trace_create_file("trace", 0644, d_tracer, | |
4000 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
4001 | ||
4002 | trace_create_file("available_tracers", 0444, d_tracer, | |
4003 | &global_trace, &show_traces_fops); | |
4004 | ||
339ae5d3 | 4005 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4006 | &global_trace, &set_tracer_fops); |
4007 | ||
4008 | trace_create_file("tracing_max_latency", 0644, d_tracer, | |
4009 | &tracing_max_latency, &tracing_max_lat_fops); | |
4010 | ||
4011 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4012 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 4013 | |
339ae5d3 | 4014 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4015 | NULL, &tracing_readme_fops); |
4016 | ||
4017 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4018 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4019 | |
4020 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
4021 | &global_trace, &tracing_entries_fops); | |
4022 | ||
4023 | trace_create_file("trace_marker", 0220, d_tracer, | |
4024 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4025 | |
69abe6a5 AP |
4026 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4027 | NULL, &tracing_saved_cmdlines_fops); | |
4028 | ||
bc0c38d1 | 4029 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4030 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4031 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4032 | #endif |
d618b3e6 IM |
4033 | #ifdef CONFIG_SYSPROF_TRACER |
4034 | init_tracer_sysprof_debugfs(d_tracer); | |
4035 | #endif | |
b04cc6b1 | 4036 | |
5452af66 FW |
4037 | create_trace_options_dir(); |
4038 | ||
b04cc6b1 FW |
4039 | for_each_tracing_cpu(cpu) |
4040 | tracing_init_debugfs_percpu(cpu); | |
4041 | ||
b5ad384e | 4042 | return 0; |
bc0c38d1 SR |
4043 | } |
4044 | ||
3f5a54e3 SR |
4045 | static int trace_panic_handler(struct notifier_block *this, |
4046 | unsigned long event, void *unused) | |
4047 | { | |
944ac425 SR |
4048 | if (ftrace_dump_on_oops) |
4049 | ftrace_dump(); | |
3f5a54e3 SR |
4050 | return NOTIFY_OK; |
4051 | } | |
4052 | ||
4053 | static struct notifier_block trace_panic_notifier = { | |
4054 | .notifier_call = trace_panic_handler, | |
4055 | .next = NULL, | |
4056 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4057 | }; | |
4058 | ||
4059 | static int trace_die_handler(struct notifier_block *self, | |
4060 | unsigned long val, | |
4061 | void *data) | |
4062 | { | |
4063 | switch (val) { | |
4064 | case DIE_OOPS: | |
944ac425 SR |
4065 | if (ftrace_dump_on_oops) |
4066 | ftrace_dump(); | |
3f5a54e3 SR |
4067 | break; |
4068 | default: | |
4069 | break; | |
4070 | } | |
4071 | return NOTIFY_OK; | |
4072 | } | |
4073 | ||
4074 | static struct notifier_block trace_die_notifier = { | |
4075 | .notifier_call = trace_die_handler, | |
4076 | .priority = 200 | |
4077 | }; | |
4078 | ||
4079 | /* | |
4080 | * printk is set to max of 1024, we really don't need it that big. | |
4081 | * Nothing should be printing 1000 characters anyway. | |
4082 | */ | |
4083 | #define TRACE_MAX_PRINT 1000 | |
4084 | ||
4085 | /* | |
4086 | * Define here KERN_TRACE so that we have one place to modify | |
4087 | * it if we decide to change what log level the ftrace dump | |
4088 | * should be at. | |
4089 | */ | |
428aee14 | 4090 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
4091 | |
4092 | static void | |
4093 | trace_printk_seq(struct trace_seq *s) | |
4094 | { | |
4095 | /* Probably should print a warning here. */ | |
4096 | if (s->len >= 1000) | |
4097 | s->len = 1000; | |
4098 | ||
4099 | /* should be zero ended, but we are paranoid. */ | |
4100 | s->buffer[s->len] = 0; | |
4101 | ||
4102 | printk(KERN_TRACE "%s", s->buffer); | |
4103 | ||
f9520750 | 4104 | trace_seq_init(s); |
3f5a54e3 SR |
4105 | } |
4106 | ||
cf586b61 | 4107 | static void __ftrace_dump(bool disable_tracing) |
3f5a54e3 SR |
4108 | { |
4109 | static DEFINE_SPINLOCK(ftrace_dump_lock); | |
4110 | /* use static because iter can be a bit big for the stack */ | |
4111 | static struct trace_iterator iter; | |
cf586b61 | 4112 | unsigned int old_userobj; |
3f5a54e3 | 4113 | static int dump_ran; |
d769041f SR |
4114 | unsigned long flags; |
4115 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4116 | |
4117 | /* only one dump */ | |
4118 | spin_lock_irqsave(&ftrace_dump_lock, flags); | |
4119 | if (dump_ran) | |
4120 | goto out; | |
4121 | ||
4122 | dump_ran = 1; | |
4123 | ||
0ee6b6cf | 4124 | tracing_off(); |
cf586b61 FW |
4125 | |
4126 | if (disable_tracing) | |
4127 | ftrace_kill(); | |
3f5a54e3 | 4128 | |
d769041f SR |
4129 | for_each_tracing_cpu(cpu) { |
4130 | atomic_inc(&global_trace.data[cpu]->disabled); | |
4131 | } | |
4132 | ||
cf586b61 FW |
4133 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4134 | ||
b54d3de9 TE |
4135 | /* don't look at user memory in panic mode */ |
4136 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4137 | ||
3f5a54e3 SR |
4138 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
4139 | ||
e543ad76 | 4140 | /* Simulate the iterator */ |
3f5a54e3 SR |
4141 | iter.tr = &global_trace; |
4142 | iter.trace = current_trace; | |
e543ad76 | 4143 | iter.cpu_file = TRACE_PIPE_ALL_CPU; |
3f5a54e3 SR |
4144 | |
4145 | /* | |
4146 | * We need to stop all tracing on all CPUS to read the | |
4147 | * the next buffer. This is a bit expensive, but is | |
4148 | * not done often. We fill all what we can read, | |
4149 | * and then release the locks again. | |
4150 | */ | |
4151 | ||
3f5a54e3 SR |
4152 | while (!trace_empty(&iter)) { |
4153 | ||
4154 | if (!cnt) | |
4155 | printk(KERN_TRACE "---------------------------------\n"); | |
4156 | ||
4157 | cnt++; | |
4158 | ||
4159 | /* reset all but tr, trace, and overruns */ | |
4160 | memset(&iter.seq, 0, | |
4161 | sizeof(struct trace_iterator) - | |
4162 | offsetof(struct trace_iterator, seq)); | |
4163 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4164 | iter.pos = -1; | |
4165 | ||
4166 | if (find_next_entry_inc(&iter) != NULL) { | |
4167 | print_trace_line(&iter); | |
4168 | trace_consume(&iter); | |
4169 | } | |
4170 | ||
4171 | trace_printk_seq(&iter.seq); | |
4172 | } | |
4173 | ||
4174 | if (!cnt) | |
4175 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4176 | else | |
4177 | printk(KERN_TRACE "---------------------------------\n"); | |
4178 | ||
cf586b61 FW |
4179 | /* Re-enable tracing if requested */ |
4180 | if (!disable_tracing) { | |
4181 | trace_flags |= old_userobj; | |
4182 | ||
4183 | for_each_tracing_cpu(cpu) { | |
4184 | atomic_dec(&global_trace.data[cpu]->disabled); | |
4185 | } | |
4186 | tracing_on(); | |
4187 | } | |
4188 | ||
3f5a54e3 SR |
4189 | out: |
4190 | spin_unlock_irqrestore(&ftrace_dump_lock, flags); | |
4191 | } | |
4192 | ||
cf586b61 FW |
4193 | /* By default: disable tracing after the dump */ |
4194 | void ftrace_dump(void) | |
4195 | { | |
4196 | __ftrace_dump(true); | |
4197 | } | |
4198 | ||
3928a8a2 | 4199 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4200 | { |
4c11d7ae | 4201 | struct trace_array_cpu *data; |
73c5162a | 4202 | int ring_buf_size; |
4c11d7ae | 4203 | int i; |
9e01c1b7 | 4204 | int ret = -ENOMEM; |
4c11d7ae | 4205 | |
9e01c1b7 RR |
4206 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4207 | goto out; | |
4208 | ||
4209 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4210 | goto out_free_buffer_mask; | |
4c11d7ae | 4211 | |
b04cc6b1 FW |
4212 | if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) |
4213 | goto out_free_tracing_cpumask; | |
4214 | ||
73c5162a SR |
4215 | /* To save memory, keep the ring buffer size to its minimum */ |
4216 | if (ring_buffer_expanded) | |
4217 | ring_buf_size = trace_buf_size; | |
4218 | else | |
4219 | ring_buf_size = 1; | |
4220 | ||
9e01c1b7 RR |
4221 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4222 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
b04cc6b1 | 4223 | cpumask_clear(tracing_reader_cpumask); |
9e01c1b7 RR |
4224 | |
4225 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
73c5162a | 4226 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4227 | TRACE_BUFFER_FLAGS); |
4228 | if (!global_trace.buffer) { | |
4229 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4230 | WARN_ON(1); | |
9e01c1b7 | 4231 | goto out_free_cpumask; |
4c11d7ae | 4232 | } |
3928a8a2 | 4233 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4234 | |
9e01c1b7 | 4235 | |
4c11d7ae | 4236 | #ifdef CONFIG_TRACER_MAX_TRACE |
73c5162a | 4237 | max_tr.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4238 | TRACE_BUFFER_FLAGS); |
4239 | if (!max_tr.buffer) { | |
4240 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4241 | WARN_ON(1); | |
4242 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4243 | goto out_free_cpumask; |
4c11d7ae | 4244 | } |
3928a8a2 SR |
4245 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
4246 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 4247 | #endif |
ab46428c | 4248 | |
4c11d7ae | 4249 | /* Allocate the first page for all buffers */ |
ab46428c | 4250 | for_each_tracing_cpu(i) { |
4c11d7ae | 4251 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 | 4252 | max_tr.data[i] = &per_cpu(max_data, i); |
4c11d7ae | 4253 | } |
bc0c38d1 | 4254 | |
bc0c38d1 SR |
4255 | trace_init_cmdlines(); |
4256 | ||
43a15386 | 4257 | register_tracer(&nop_trace); |
79fb0768 | 4258 | current_trace = &nop_trace; |
b5ad384e FW |
4259 | #ifdef CONFIG_BOOT_TRACER |
4260 | register_tracer(&boot_tracer); | |
b5ad384e | 4261 | #endif |
60a11774 SR |
4262 | /* All seems OK, enable tracing */ |
4263 | tracing_disabled = 0; | |
3928a8a2 | 4264 | |
3f5a54e3 SR |
4265 | atomic_notifier_chain_register(&panic_notifier_list, |
4266 | &trace_panic_notifier); | |
4267 | ||
4268 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4269 | |
4270 | return 0; | |
3f5a54e3 | 4271 | |
9e01c1b7 | 4272 | out_free_cpumask: |
b04cc6b1 FW |
4273 | free_cpumask_var(tracing_reader_cpumask); |
4274 | out_free_tracing_cpumask: | |
9e01c1b7 RR |
4275 | free_cpumask_var(tracing_cpumask); |
4276 | out_free_buffer_mask: | |
4277 | free_cpumask_var(tracing_buffer_mask); | |
4278 | out: | |
4279 | return ret; | |
bc0c38d1 | 4280 | } |
b2821ae6 SR |
4281 | |
4282 | __init static int clear_boot_tracer(void) | |
4283 | { | |
4284 | /* | |
4285 | * The default tracer at boot buffer is an init section. | |
4286 | * This function is called in lateinit. If we did not | |
4287 | * find the boot tracer, then clear it out, to prevent | |
4288 | * later registration from accessing the buffer that is | |
4289 | * about to be freed. | |
4290 | */ | |
4291 | if (!default_bootup_tracer) | |
4292 | return 0; | |
4293 | ||
4294 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4295 | default_bootup_tracer); | |
4296 | default_bootup_tracer = NULL; | |
4297 | ||
4298 | return 0; | |
4299 | } | |
4300 | ||
b5ad384e FW |
4301 | early_initcall(tracer_alloc_buffers); |
4302 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4303 | late_initcall(clear_boot_tracer); |