Commit | Line | Data |
---|---|---|
bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
bc0c38d1 | 15 | #include <linux/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
405f5571 | 20 | #include <linux/smp_lock.h> |
3f5a54e3 | 21 | #include <linux/notifier.h> |
2cadf913 | 22 | #include <linux/irqflags.h> |
bc0c38d1 | 23 | #include <linux/debugfs.h> |
4c11d7ae | 24 | #include <linux/pagemap.h> |
bc0c38d1 SR |
25 | #include <linux/hardirq.h> |
26 | #include <linux/linkage.h> | |
27 | #include <linux/uaccess.h> | |
2cadf913 | 28 | #include <linux/kprobes.h> |
bc0c38d1 SR |
29 | #include <linux/ftrace.h> |
30 | #include <linux/module.h> | |
31 | #include <linux/percpu.h> | |
2cadf913 | 32 | #include <linux/splice.h> |
3f5a54e3 | 33 | #include <linux/kdebug.h> |
5f0c6c03 | 34 | #include <linux/string.h> |
bc0c38d1 SR |
35 | #include <linux/ctype.h> |
36 | #include <linux/init.h> | |
2a2cc8f7 | 37 | #include <linux/poll.h> |
bc0c38d1 SR |
38 | #include <linux/gfp.h> |
39 | #include <linux/fs.h> | |
86387f7e | 40 | |
bc0c38d1 | 41 | #include "trace.h" |
f0868d1e | 42 | #include "trace_output.h" |
bc0c38d1 | 43 | |
3928a8a2 SR |
44 | #define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE) |
45 | ||
745b1626 | 46 | unsigned long __read_mostly tracing_max_latency; |
bc0c38d1 SR |
47 | unsigned long __read_mostly tracing_thresh; |
48 | ||
73c5162a SR |
49 | /* |
50 | * On boot up, the ring buffer is set to the minimum size, so that | |
51 | * we do not waste memory on systems that are not using tracing. | |
52 | */ | |
53 | static int ring_buffer_expanded; | |
54 | ||
8e1b82e0 FW |
55 | /* |
56 | * We need to change this state when a selftest is running. | |
ff32504f FW |
57 | * A selftest will lurk into the ring-buffer to count the |
58 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 59 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
60 | * at the same time, giving false positive or negative results. |
61 | */ | |
8e1b82e0 | 62 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 63 | |
b2821ae6 SR |
64 | /* |
65 | * If a tracer is running, we do not want to run SELFTEST. | |
66 | */ | |
67 | static bool __read_mostly tracing_selftest_disabled; | |
68 | ||
adf9f195 FW |
69 | /* For tracers that don't implement custom flags */ |
70 | static struct tracer_opt dummy_tracer_opt[] = { | |
71 | { } | |
72 | }; | |
73 | ||
74 | static struct tracer_flags dummy_tracer_flags = { | |
75 | .val = 0, | |
76 | .opts = dummy_tracer_opt | |
77 | }; | |
78 | ||
79 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
80 | { | |
81 | return 0; | |
82 | } | |
0f048701 SR |
83 | |
84 | /* | |
85 | * Kill all tracing for good (never come back). | |
86 | * It is initialized to 1 but will turn to zero if the initialization | |
87 | * of the tracer is successful. But that is the only place that sets | |
88 | * this back to zero. | |
89 | */ | |
4fd27358 | 90 | static int tracing_disabled = 1; |
0f048701 | 91 | |
d769041f SR |
92 | static DEFINE_PER_CPU(local_t, ftrace_cpu_disabled); |
93 | ||
94 | static inline void ftrace_disable_cpu(void) | |
95 | { | |
96 | preempt_disable(); | |
97 | local_inc(&__get_cpu_var(ftrace_cpu_disabled)); | |
98 | } | |
99 | ||
100 | static inline void ftrace_enable_cpu(void) | |
101 | { | |
102 | local_dec(&__get_cpu_var(ftrace_cpu_disabled)); | |
103 | preempt_enable(); | |
104 | } | |
105 | ||
9e01c1b7 | 106 | static cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 107 | |
b04cc6b1 FW |
108 | /* Define which cpu buffers are currently read in trace_pipe */ |
109 | static cpumask_var_t tracing_reader_cpumask; | |
110 | ||
ab46428c | 111 | #define for_each_tracing_cpu(cpu) \ |
9e01c1b7 | 112 | for_each_cpu(cpu, tracing_buffer_mask) |
ab46428c | 113 | |
944ac425 SR |
114 | /* |
115 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
116 | * | |
117 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
118 | * is set, then ftrace_dump is called. This will output the contents | |
119 | * of the ftrace buffers to the console. This is very useful for | |
120 | * capturing traces that lead to crashes and outputing it to a | |
121 | * serial console. | |
122 | * | |
123 | * It is default off, but you can enable it with either specifying | |
124 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
125 | * /proc/sys/kernel/ftrace_dump_on_oops to true. | |
126 | */ | |
127 | int ftrace_dump_on_oops; | |
128 | ||
b2821ae6 SR |
129 | static int tracing_set_tracer(const char *buf); |
130 | ||
131 | #define BOOTUP_TRACER_SIZE 100 | |
132 | static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata; | |
133 | static char *default_bootup_tracer; | |
d9e54076 PZ |
134 | |
135 | static int __init set_ftrace(char *str) | |
136 | { | |
b2821ae6 SR |
137 | strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); |
138 | default_bootup_tracer = bootup_tracer_buf; | |
73c5162a SR |
139 | /* We are using ftrace early, expand it */ |
140 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
141 | return 1; |
142 | } | |
b2821ae6 | 143 | __setup("ftrace=", set_ftrace); |
d9e54076 | 144 | |
944ac425 SR |
145 | static int __init set_ftrace_dump_on_oops(char *str) |
146 | { | |
147 | ftrace_dump_on_oops = 1; | |
148 | return 1; | |
149 | } | |
150 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 151 | |
cf8e3474 | 152 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
153 | { |
154 | nsec += 500; | |
155 | do_div(nsec, 1000); | |
156 | return nsec; | |
157 | } | |
158 | ||
4fcdae83 SR |
159 | /* |
160 | * The global_trace is the descriptor that holds the tracing | |
161 | * buffers for the live tracing. For each CPU, it contains | |
162 | * a link list of pages that will store trace entries. The | |
163 | * page descriptor of the pages in the memory is used to hold | |
164 | * the link list by linking the lru item in the page descriptor | |
165 | * to each of the pages in the buffer per CPU. | |
166 | * | |
167 | * For each active CPU there is a data field that holds the | |
168 | * pages for the buffer for that CPU. Each CPU has the same number | |
169 | * of pages allocated for its buffer. | |
170 | */ | |
bc0c38d1 SR |
171 | static struct trace_array global_trace; |
172 | ||
173 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
174 | ||
eb02ce01 TZ |
175 | int filter_current_check_discard(struct ftrace_event_call *call, void *rec, |
176 | struct ring_buffer_event *event) | |
177 | { | |
178 | return filter_check_discard(call, rec, global_trace.buffer, event); | |
179 | } | |
17c873ec | 180 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 181 | |
37886f6a SR |
182 | cycle_t ftrace_now(int cpu) |
183 | { | |
184 | u64 ts; | |
185 | ||
186 | /* Early boot up does not have a buffer yet */ | |
187 | if (!global_trace.buffer) | |
188 | return trace_clock_local(); | |
189 | ||
190 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
191 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
192 | ||
193 | return ts; | |
194 | } | |
bc0c38d1 | 195 | |
4fcdae83 SR |
196 | /* |
197 | * The max_tr is used to snapshot the global_trace when a maximum | |
198 | * latency is reached. Some tracers will use this to store a maximum | |
199 | * trace while it continues examining live traces. | |
200 | * | |
201 | * The buffers for the max_tr are set up the same as the global_trace. | |
202 | * When a snapshot is taken, the link list of the max_tr is swapped | |
203 | * with the link list of the global_trace and the buffers are reset for | |
204 | * the global_trace so the tracing can continue. | |
205 | */ | |
bc0c38d1 SR |
206 | static struct trace_array max_tr; |
207 | ||
208 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
209 | ||
4fcdae83 | 210 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 211 | static int tracer_enabled = 1; |
4fcdae83 | 212 | |
9036990d SR |
213 | /** |
214 | * tracing_is_enabled - return tracer_enabled status | |
215 | * | |
216 | * This function is used by other tracers to know the status | |
217 | * of the tracer_enabled flag. Tracers may use this function | |
218 | * to know if it should enable their features when starting | |
219 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
220 | */ | |
221 | int tracing_is_enabled(void) | |
222 | { | |
223 | return tracer_enabled; | |
224 | } | |
225 | ||
4fcdae83 | 226 | /* |
3928a8a2 SR |
227 | * trace_buf_size is the size in bytes that is allocated |
228 | * for a buffer. Note, the number of bytes is always rounded | |
229 | * to page size. | |
3f5a54e3 SR |
230 | * |
231 | * This number is purposely set to a low number of 16384. | |
232 | * If the dump on oops happens, it will be much appreciated | |
233 | * to not have to wait for all that output. Anyway this can be | |
234 | * boot time and run time configurable. | |
4fcdae83 | 235 | */ |
3928a8a2 | 236 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 237 | |
3928a8a2 | 238 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 239 | |
4fcdae83 | 240 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 241 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
242 | |
243 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 244 | static struct tracer *current_trace __read_mostly; |
4fcdae83 SR |
245 | |
246 | /* | |
247 | * max_tracer_type_len is used to simplify the allocating of | |
248 | * buffers to read userspace tracer names. We keep track of | |
249 | * the longest tracer name registered. | |
250 | */ | |
bc0c38d1 SR |
251 | static int max_tracer_type_len; |
252 | ||
4fcdae83 SR |
253 | /* |
254 | * trace_types_lock is used to protect the trace_types list. | |
255 | * This lock is also used to keep user access serialized. | |
256 | * Accesses from userspace will grab this lock while userspace | |
257 | * activities happen inside the kernel. | |
258 | */ | |
bc0c38d1 | 259 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
260 | |
261 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
262 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
263 | ||
ee6bce52 | 264 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 265 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a SR |
266 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
267 | TRACE_ITER_GRAPH_TIME; | |
4e655519 | 268 | |
4fcdae83 SR |
269 | /** |
270 | * trace_wake_up - wake up tasks waiting for trace input | |
271 | * | |
272 | * Simply wakes up any task that is blocked on the trace_wait | |
273 | * queue. These is used with trace_poll for tasks polling the trace. | |
274 | */ | |
4e655519 IM |
275 | void trace_wake_up(void) |
276 | { | |
017730c1 IM |
277 | /* |
278 | * The runqueue_is_locked() can fail, but this is the best we | |
279 | * have for now: | |
280 | */ | |
281 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
282 | wake_up(&trace_wait); |
283 | } | |
bc0c38d1 | 284 | |
3928a8a2 | 285 | static int __init set_buf_size(char *str) |
bc0c38d1 | 286 | { |
3928a8a2 | 287 | unsigned long buf_size; |
c6caeeb1 | 288 | |
bc0c38d1 SR |
289 | if (!str) |
290 | return 0; | |
9d612bef | 291 | buf_size = memparse(str, &str); |
c6caeeb1 | 292 | /* nr_entries can not be zero */ |
9d612bef | 293 | if (buf_size == 0) |
c6caeeb1 | 294 | return 0; |
3928a8a2 | 295 | trace_buf_size = buf_size; |
bc0c38d1 SR |
296 | return 1; |
297 | } | |
3928a8a2 | 298 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 299 | |
57f50be1 SR |
300 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
301 | { | |
302 | return nsecs / 1000; | |
303 | } | |
304 | ||
4fcdae83 | 305 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
306 | static const char *trace_options[] = { |
307 | "print-parent", | |
308 | "sym-offset", | |
309 | "sym-addr", | |
310 | "verbose", | |
f9896bf3 | 311 | "raw", |
5e3ca0ec | 312 | "hex", |
cb0f12aa | 313 | "bin", |
2a2cc8f7 | 314 | "block", |
86387f7e | 315 | "stacktrace", |
4ac3ba41 | 316 | "sched-tree", |
5e1607a0 | 317 | "trace_printk", |
b2a866f9 | 318 | "ftrace_preempt", |
9f029e83 | 319 | "branch", |
12ef7d44 | 320 | "annotate", |
02b67518 | 321 | "userstacktrace", |
b54d3de9 | 322 | "sym-userobj", |
66896a85 | 323 | "printk-msg-only", |
c4a8e8be | 324 | "context-info", |
c032ef64 | 325 | "latency-format", |
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, | |
156f5a78 | 347 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) |
bc0c38d1 | 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 | ||
9456f0fa SR |
642 | void tracing_reset_current(int cpu) |
643 | { | |
644 | tracing_reset(&global_trace, cpu); | |
645 | } | |
646 | ||
647 | void tracing_reset_current_online_cpus(void) | |
648 | { | |
649 | tracing_reset_online_cpus(&global_trace); | |
650 | } | |
651 | ||
bc0c38d1 | 652 | #define SAVED_CMDLINES 128 |
2c7eea4c | 653 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
654 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
655 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
656 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
657 | static int cmdline_idx; | |
efed792d | 658 | static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; |
25b0b44a | 659 | |
25b0b44a | 660 | /* temporary disable recording */ |
4fd27358 | 661 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
662 | |
663 | static void trace_init_cmdlines(void) | |
664 | { | |
2c7eea4c TG |
665 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
666 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
667 | cmdline_idx = 0; |
668 | } | |
669 | ||
0f048701 SR |
670 | static int trace_stop_count; |
671 | static DEFINE_SPINLOCK(tracing_start_lock); | |
672 | ||
69bb54ec SR |
673 | /** |
674 | * ftrace_off_permanent - disable all ftrace code permanently | |
675 | * | |
676 | * This should only be called when a serious anomally has | |
677 | * been detected. This will turn off the function tracing, | |
678 | * ring buffers, and other tracing utilites. It takes no | |
679 | * locks and can be called from any context. | |
680 | */ | |
681 | void ftrace_off_permanent(void) | |
682 | { | |
683 | tracing_disabled = 1; | |
684 | ftrace_stop(); | |
685 | tracing_off_permanent(); | |
686 | } | |
687 | ||
0f048701 SR |
688 | /** |
689 | * tracing_start - quick start of the tracer | |
690 | * | |
691 | * If tracing is enabled but was stopped by tracing_stop, | |
692 | * this will start the tracer back up. | |
693 | */ | |
694 | void tracing_start(void) | |
695 | { | |
696 | struct ring_buffer *buffer; | |
697 | unsigned long flags; | |
698 | ||
699 | if (tracing_disabled) | |
700 | return; | |
701 | ||
702 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
703 | if (--trace_stop_count) { |
704 | if (trace_stop_count < 0) { | |
705 | /* Someone screwed up their debugging */ | |
706 | WARN_ON_ONCE(1); | |
707 | trace_stop_count = 0; | |
708 | } | |
0f048701 SR |
709 | goto out; |
710 | } | |
711 | ||
712 | ||
713 | buffer = global_trace.buffer; | |
714 | if (buffer) | |
715 | ring_buffer_record_enable(buffer); | |
716 | ||
717 | buffer = max_tr.buffer; | |
718 | if (buffer) | |
719 | ring_buffer_record_enable(buffer); | |
720 | ||
721 | ftrace_start(); | |
722 | out: | |
723 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
724 | } | |
725 | ||
726 | /** | |
727 | * tracing_stop - quick stop of the tracer | |
728 | * | |
729 | * Light weight way to stop tracing. Use in conjunction with | |
730 | * tracing_start. | |
731 | */ | |
732 | void tracing_stop(void) | |
733 | { | |
734 | struct ring_buffer *buffer; | |
735 | unsigned long flags; | |
736 | ||
737 | ftrace_stop(); | |
738 | spin_lock_irqsave(&tracing_start_lock, flags); | |
739 | if (trace_stop_count++) | |
740 | goto out; | |
741 | ||
742 | buffer = global_trace.buffer; | |
743 | if (buffer) | |
744 | ring_buffer_record_disable(buffer); | |
745 | ||
746 | buffer = max_tr.buffer; | |
747 | if (buffer) | |
748 | ring_buffer_record_disable(buffer); | |
749 | ||
750 | out: | |
751 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
752 | } | |
753 | ||
e309b41d | 754 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 755 | |
e309b41d | 756 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 757 | { |
a635cf04 | 758 | unsigned pid, idx; |
bc0c38d1 SR |
759 | |
760 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
761 | return; | |
762 | ||
763 | /* | |
764 | * It's not the end of the world if we don't get | |
765 | * the lock, but we also don't want to spin | |
766 | * nor do we want to disable interrupts, | |
767 | * so if we miss here, then better luck next time. | |
768 | */ | |
efed792d | 769 | if (!__raw_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
770 | return; |
771 | ||
772 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 773 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
774 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
775 | ||
a635cf04 CE |
776 | /* |
777 | * Check whether the cmdline buffer at idx has a pid | |
778 | * mapped. We are going to overwrite that entry so we | |
779 | * need to clear the map_pid_to_cmdline. Otherwise we | |
780 | * would read the new comm for the old pid. | |
781 | */ | |
782 | pid = map_cmdline_to_pid[idx]; | |
783 | if (pid != NO_CMDLINE_MAP) | |
784 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 785 | |
a635cf04 | 786 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
787 | map_pid_to_cmdline[tsk->pid] = idx; |
788 | ||
789 | cmdline_idx = idx; | |
790 | } | |
791 | ||
792 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
793 | ||
efed792d | 794 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
795 | } |
796 | ||
4ca53085 | 797 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 798 | { |
bc0c38d1 SR |
799 | unsigned map; |
800 | ||
4ca53085 SR |
801 | if (!pid) { |
802 | strcpy(comm, "<idle>"); | |
803 | return; | |
804 | } | |
bc0c38d1 | 805 | |
4ca53085 SR |
806 | if (pid > PID_MAX_DEFAULT) { |
807 | strcpy(comm, "<...>"); | |
808 | return; | |
809 | } | |
bc0c38d1 | 810 | |
5b6045a9 | 811 | preempt_disable(); |
4ca53085 | 812 | __raw_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 813 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
814 | if (map != NO_CMDLINE_MAP) |
815 | strcpy(comm, saved_cmdlines[map]); | |
816 | else | |
817 | strcpy(comm, "<...>"); | |
bc0c38d1 | 818 | |
4ca53085 | 819 | __raw_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 820 | preempt_enable(); |
bc0c38d1 SR |
821 | } |
822 | ||
e309b41d | 823 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 824 | { |
18aecd36 TG |
825 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
826 | !tracing_is_on()) | |
bc0c38d1 SR |
827 | return; |
828 | ||
829 | trace_save_cmdline(tsk); | |
830 | } | |
831 | ||
45dcd8b8 | 832 | void |
38697053 SR |
833 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
834 | int pc) | |
bc0c38d1 SR |
835 | { |
836 | struct task_struct *tsk = current; | |
bc0c38d1 | 837 | |
777e208d SR |
838 | entry->preempt_count = pc & 0xff; |
839 | entry->pid = (tsk) ? tsk->pid : 0; | |
ef18012b | 840 | entry->tgid = (tsk) ? tsk->tgid : 0; |
777e208d | 841 | entry->flags = |
9244489a | 842 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 843 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
844 | #else |
845 | TRACE_FLAG_IRQS_NOSUPPORT | | |
846 | #endif | |
bc0c38d1 SR |
847 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
848 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
849 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
850 | } | |
f413cdb8 | 851 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 852 | |
51a763dd | 853 | struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr, |
7a4f453b | 854 | int type, |
51a763dd ACM |
855 | unsigned long len, |
856 | unsigned long flags, int pc) | |
857 | { | |
858 | struct ring_buffer_event *event; | |
859 | ||
860 | event = ring_buffer_lock_reserve(tr->buffer, len); | |
861 | if (event != NULL) { | |
862 | struct trace_entry *ent = ring_buffer_event_data(event); | |
863 | ||
864 | tracing_generic_entry_update(ent, flags, pc); | |
865 | ent->type = type; | |
866 | } | |
867 | ||
868 | return event; | |
869 | } | |
870 | static void ftrace_trace_stack(struct trace_array *tr, | |
871 | unsigned long flags, int skip, int pc); | |
872 | static void ftrace_trace_userstack(struct trace_array *tr, | |
873 | unsigned long flags, int pc); | |
874 | ||
07edf712 FW |
875 | static inline void __trace_buffer_unlock_commit(struct trace_array *tr, |
876 | struct ring_buffer_event *event, | |
877 | unsigned long flags, int pc, | |
878 | int wake) | |
51a763dd ACM |
879 | { |
880 | ring_buffer_unlock_commit(tr->buffer, event); | |
881 | ||
882 | ftrace_trace_stack(tr, flags, 6, pc); | |
883 | ftrace_trace_userstack(tr, flags, pc); | |
07edf712 FW |
884 | |
885 | if (wake) | |
886 | trace_wake_up(); | |
887 | } | |
888 | ||
889 | void trace_buffer_unlock_commit(struct trace_array *tr, | |
890 | struct ring_buffer_event *event, | |
891 | unsigned long flags, int pc) | |
892 | { | |
893 | __trace_buffer_unlock_commit(tr, event, flags, pc, 1); | |
51a763dd ACM |
894 | } |
895 | ||
ef5580d0 | 896 | struct ring_buffer_event * |
7a4f453b | 897 | trace_current_buffer_lock_reserve(int type, unsigned long len, |
ef5580d0 SR |
898 | unsigned long flags, int pc) |
899 | { | |
900 | return trace_buffer_lock_reserve(&global_trace, | |
901 | type, len, flags, pc); | |
902 | } | |
94487d6d | 903 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 SR |
904 | |
905 | void trace_current_buffer_unlock_commit(struct ring_buffer_event *event, | |
906 | unsigned long flags, int pc) | |
907 | { | |
77d9f465 | 908 | __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 1); |
07edf712 | 909 | } |
94487d6d | 910 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 FW |
911 | |
912 | void trace_nowake_buffer_unlock_commit(struct ring_buffer_event *event, | |
913 | unsigned long flags, int pc) | |
914 | { | |
77d9f465 SR |
915 | __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 0); |
916 | } | |
94487d6d | 917 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 SR |
918 | |
919 | void trace_current_buffer_discard_commit(struct ring_buffer_event *event) | |
920 | { | |
921 | ring_buffer_discard_commit(global_trace.buffer, event); | |
ef5580d0 | 922 | } |
12acd473 | 923 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 924 | |
e309b41d | 925 | void |
7be42151 | 926 | trace_function(struct trace_array *tr, |
38697053 SR |
927 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
928 | int pc) | |
bc0c38d1 | 929 | { |
e1112b4d | 930 | struct ftrace_event_call *call = &event_function; |
3928a8a2 | 931 | struct ring_buffer_event *event; |
777e208d | 932 | struct ftrace_entry *entry; |
bc0c38d1 | 933 | |
d769041f SR |
934 | /* If we are reading the ring buffer, don't trace */ |
935 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
936 | return; | |
937 | ||
51a763dd ACM |
938 | event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry), |
939 | flags, pc); | |
3928a8a2 SR |
940 | if (!event) |
941 | return; | |
942 | entry = ring_buffer_event_data(event); | |
777e208d SR |
943 | entry->ip = ip; |
944 | entry->parent_ip = parent_ip; | |
e1112b4d | 945 | |
eb02ce01 TZ |
946 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
947 | ring_buffer_unlock_commit(tr->buffer, event); | |
bc0c38d1 SR |
948 | } |
949 | ||
fb52607a | 950 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
16185369 | 951 | static int __trace_graph_entry(struct trace_array *tr, |
287b6e68 FW |
952 | struct ftrace_graph_ent *trace, |
953 | unsigned long flags, | |
954 | int pc) | |
955 | { | |
e1112b4d | 956 | struct ftrace_event_call *call = &event_funcgraph_entry; |
287b6e68 FW |
957 | struct ring_buffer_event *event; |
958 | struct ftrace_graph_ent_entry *entry; | |
287b6e68 FW |
959 | |
960 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
16185369 | 961 | return 0; |
287b6e68 | 962 | |
51a763dd ACM |
963 | event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_ENT, |
964 | sizeof(*entry), flags, pc); | |
287b6e68 | 965 | if (!event) |
16185369 | 966 | return 0; |
287b6e68 | 967 | entry = ring_buffer_event_data(event); |
287b6e68 | 968 | entry->graph_ent = *trace; |
eb02ce01 TZ |
969 | if (!filter_current_check_discard(call, entry, event)) |
970 | ring_buffer_unlock_commit(global_trace.buffer, event); | |
16185369 FW |
971 | |
972 | return 1; | |
287b6e68 FW |
973 | } |
974 | ||
975 | static void __trace_graph_return(struct trace_array *tr, | |
fb52607a | 976 | struct ftrace_graph_ret *trace, |
15e6cb36 FW |
977 | unsigned long flags, |
978 | int pc) | |
979 | { | |
e1112b4d | 980 | struct ftrace_event_call *call = &event_funcgraph_exit; |
15e6cb36 | 981 | struct ring_buffer_event *event; |
287b6e68 | 982 | struct ftrace_graph_ret_entry *entry; |
15e6cb36 FW |
983 | |
984 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
985 | return; | |
986 | ||
51a763dd ACM |
987 | event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_RET, |
988 | sizeof(*entry), flags, pc); | |
15e6cb36 FW |
989 | if (!event) |
990 | return; | |
991 | entry = ring_buffer_event_data(event); | |
287b6e68 | 992 | entry->ret = *trace; |
eb02ce01 TZ |
993 | if (!filter_current_check_discard(call, entry, event)) |
994 | ring_buffer_unlock_commit(global_trace.buffer, event); | |
15e6cb36 FW |
995 | } |
996 | #endif | |
997 | ||
e309b41d | 998 | void |
2e0f5761 | 999 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
1000 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
1001 | int pc) | |
2e0f5761 IM |
1002 | { |
1003 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 1004 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
1005 | } |
1006 | ||
53614991 | 1007 | static void __ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
1008 | unsigned long flags, |
1009 | int skip, int pc) | |
86387f7e | 1010 | { |
c2c80529 | 1011 | #ifdef CONFIG_STACKTRACE |
e1112b4d | 1012 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 1013 | struct ring_buffer_event *event; |
777e208d | 1014 | struct stack_entry *entry; |
86387f7e IM |
1015 | struct stack_trace trace; |
1016 | ||
51a763dd ACM |
1017 | event = trace_buffer_lock_reserve(tr, TRACE_STACK, |
1018 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1019 | if (!event) |
1020 | return; | |
1021 | entry = ring_buffer_event_data(event); | |
777e208d | 1022 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
1023 | |
1024 | trace.nr_entries = 0; | |
1025 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1026 | trace.skip = skip; | |
777e208d | 1027 | trace.entries = entry->caller; |
86387f7e IM |
1028 | |
1029 | save_stack_trace(&trace); | |
eb02ce01 TZ |
1030 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1031 | ring_buffer_unlock_commit(tr->buffer, event); | |
c2c80529 | 1032 | #endif |
f0a920d5 IM |
1033 | } |
1034 | ||
53614991 | 1035 | static void ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
1036 | unsigned long flags, |
1037 | int skip, int pc) | |
1038 | { | |
1039 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1040 | return; | |
1041 | ||
7be42151 | 1042 | __ftrace_trace_stack(tr, flags, skip, pc); |
53614991 SR |
1043 | } |
1044 | ||
38697053 | 1045 | void __trace_stack(struct trace_array *tr, |
38697053 | 1046 | unsigned long flags, |
53614991 | 1047 | int skip, int pc) |
38697053 | 1048 | { |
7be42151 | 1049 | __ftrace_trace_stack(tr, flags, skip, pc); |
38697053 SR |
1050 | } |
1051 | ||
02b67518 | 1052 | static void ftrace_trace_userstack(struct trace_array *tr, |
7be42151 | 1053 | unsigned long flags, int pc) |
02b67518 | 1054 | { |
c7425acb | 1055 | #ifdef CONFIG_STACKTRACE |
e1112b4d | 1056 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1057 | struct ring_buffer_event *event; |
02b67518 TE |
1058 | struct userstack_entry *entry; |
1059 | struct stack_trace trace; | |
02b67518 TE |
1060 | |
1061 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1062 | return; | |
1063 | ||
51a763dd ACM |
1064 | event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK, |
1065 | sizeof(*entry), flags, pc); | |
02b67518 TE |
1066 | if (!event) |
1067 | return; | |
1068 | entry = ring_buffer_event_data(event); | |
02b67518 TE |
1069 | |
1070 | memset(&entry->caller, 0, sizeof(entry->caller)); | |
1071 | ||
1072 | trace.nr_entries = 0; | |
1073 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1074 | trace.skip = 0; | |
1075 | trace.entries = entry->caller; | |
1076 | ||
1077 | save_stack_trace_user(&trace); | |
eb02ce01 TZ |
1078 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1079 | ring_buffer_unlock_commit(tr->buffer, event); | |
c7425acb | 1080 | #endif |
02b67518 TE |
1081 | } |
1082 | ||
4fd27358 HE |
1083 | #ifdef UNUSED |
1084 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1085 | { |
7be42151 | 1086 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1087 | } |
4fd27358 | 1088 | #endif /* UNUSED */ |
02b67518 | 1089 | |
38697053 | 1090 | static void |
7be42151 | 1091 | ftrace_trace_special(void *__tr, |
38697053 SR |
1092 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1093 | int pc) | |
a4feb834 | 1094 | { |
3928a8a2 | 1095 | struct ring_buffer_event *event; |
a4feb834 | 1096 | struct trace_array *tr = __tr; |
777e208d | 1097 | struct special_entry *entry; |
a4feb834 | 1098 | |
51a763dd ACM |
1099 | event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL, |
1100 | sizeof(*entry), 0, pc); | |
3928a8a2 SR |
1101 | if (!event) |
1102 | return; | |
1103 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1104 | entry->arg1 = arg1; |
1105 | entry->arg2 = arg2; | |
1106 | entry->arg3 = arg3; | |
51a763dd | 1107 | trace_buffer_unlock_commit(tr, event, 0, pc); |
a4feb834 IM |
1108 | } |
1109 | ||
38697053 SR |
1110 | void |
1111 | __trace_special(void *__tr, void *__data, | |
1112 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1113 | { | |
7be42151 | 1114 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1115 | } |
1116 | ||
e309b41d | 1117 | void |
bc0c38d1 | 1118 | tracing_sched_switch_trace(struct trace_array *tr, |
86387f7e IM |
1119 | struct task_struct *prev, |
1120 | struct task_struct *next, | |
38697053 | 1121 | unsigned long flags, int pc) |
bc0c38d1 | 1122 | { |
e1112b4d | 1123 | struct ftrace_event_call *call = &event_context_switch; |
3928a8a2 | 1124 | struct ring_buffer_event *event; |
777e208d | 1125 | struct ctx_switch_entry *entry; |
bc0c38d1 | 1126 | |
51a763dd ACM |
1127 | event = trace_buffer_lock_reserve(tr, TRACE_CTX, |
1128 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1129 | if (!event) |
1130 | return; | |
1131 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1132 | entry->prev_pid = prev->pid; |
1133 | entry->prev_prio = prev->prio; | |
1134 | entry->prev_state = prev->state; | |
1135 | entry->next_pid = next->pid; | |
1136 | entry->next_prio = next->prio; | |
1137 | entry->next_state = next->state; | |
1138 | entry->next_cpu = task_cpu(next); | |
e1112b4d | 1139 | |
eb02ce01 TZ |
1140 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1141 | trace_buffer_unlock_commit(tr, event, flags, pc); | |
bc0c38d1 SR |
1142 | } |
1143 | ||
57422797 IM |
1144 | void |
1145 | tracing_sched_wakeup_trace(struct trace_array *tr, | |
86387f7e IM |
1146 | struct task_struct *wakee, |
1147 | struct task_struct *curr, | |
38697053 | 1148 | unsigned long flags, int pc) |
57422797 | 1149 | { |
e1112b4d | 1150 | struct ftrace_event_call *call = &event_wakeup; |
3928a8a2 | 1151 | struct ring_buffer_event *event; |
777e208d | 1152 | struct ctx_switch_entry *entry; |
57422797 | 1153 | |
51a763dd ACM |
1154 | event = trace_buffer_lock_reserve(tr, TRACE_WAKE, |
1155 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1156 | if (!event) |
1157 | return; | |
1158 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1159 | entry->prev_pid = curr->pid; |
1160 | entry->prev_prio = curr->prio; | |
1161 | entry->prev_state = curr->state; | |
1162 | entry->next_pid = wakee->pid; | |
1163 | entry->next_prio = wakee->prio; | |
1164 | entry->next_state = wakee->state; | |
1165 | entry->next_cpu = task_cpu(wakee); | |
6eaaa5d5 | 1166 | |
eb02ce01 TZ |
1167 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1168 | ring_buffer_unlock_commit(tr->buffer, event); | |
6eaaa5d5 FW |
1169 | ftrace_trace_stack(tr, flags, 6, pc); |
1170 | ftrace_trace_userstack(tr, flags, pc); | |
57422797 IM |
1171 | } |
1172 | ||
4902f884 SR |
1173 | void |
1174 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1175 | { | |
1176 | struct trace_array *tr = &global_trace; | |
1177 | struct trace_array_cpu *data; | |
5aa1ba6a | 1178 | unsigned long flags; |
4902f884 | 1179 | int cpu; |
38697053 | 1180 | int pc; |
4902f884 | 1181 | |
c76f0694 | 1182 | if (tracing_disabled) |
4902f884 SR |
1183 | return; |
1184 | ||
38697053 | 1185 | pc = preempt_count(); |
5aa1ba6a | 1186 | local_irq_save(flags); |
4902f884 SR |
1187 | cpu = raw_smp_processor_id(); |
1188 | data = tr->data[cpu]; | |
4902f884 | 1189 | |
5aa1ba6a | 1190 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1191 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1192 | |
5aa1ba6a SR |
1193 | atomic_dec(&data->disabled); |
1194 | local_irq_restore(flags); | |
4902f884 SR |
1195 | } |
1196 | ||
fb52607a | 1197 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e49dc19c | 1198 | int trace_graph_entry(struct ftrace_graph_ent *trace) |
15e6cb36 FW |
1199 | { |
1200 | struct trace_array *tr = &global_trace; | |
1201 | struct trace_array_cpu *data; | |
1202 | unsigned long flags; | |
1203 | long disabled; | |
16185369 | 1204 | int ret; |
15e6cb36 FW |
1205 | int cpu; |
1206 | int pc; | |
1207 | ||
804a6851 SR |
1208 | if (!ftrace_trace_task(current)) |
1209 | return 0; | |
1210 | ||
ea4e2bc4 SR |
1211 | if (!ftrace_graph_addr(trace->func)) |
1212 | return 0; | |
1213 | ||
a5e25883 | 1214 | local_irq_save(flags); |
15e6cb36 FW |
1215 | cpu = raw_smp_processor_id(); |
1216 | data = tr->data[cpu]; | |
1217 | disabled = atomic_inc_return(&data->disabled); | |
1218 | if (likely(disabled == 1)) { | |
1219 | pc = preempt_count(); | |
16185369 FW |
1220 | ret = __trace_graph_entry(tr, trace, flags, pc); |
1221 | } else { | |
1222 | ret = 0; | |
287b6e68 | 1223 | } |
ea4e2bc4 SR |
1224 | /* Only do the atomic if it is not already set */ |
1225 | if (!test_tsk_trace_graph(current)) | |
1226 | set_tsk_trace_graph(current); | |
16185369 | 1227 | |
287b6e68 | 1228 | atomic_dec(&data->disabled); |
a5e25883 | 1229 | local_irq_restore(flags); |
e49dc19c | 1230 | |
16185369 | 1231 | return ret; |
287b6e68 FW |
1232 | } |
1233 | ||
1234 | void trace_graph_return(struct ftrace_graph_ret *trace) | |
1235 | { | |
1236 | struct trace_array *tr = &global_trace; | |
1237 | struct trace_array_cpu *data; | |
1238 | unsigned long flags; | |
1239 | long disabled; | |
1240 | int cpu; | |
1241 | int pc; | |
1242 | ||
a5e25883 | 1243 | local_irq_save(flags); |
287b6e68 FW |
1244 | cpu = raw_smp_processor_id(); |
1245 | data = tr->data[cpu]; | |
1246 | disabled = atomic_inc_return(&data->disabled); | |
1247 | if (likely(disabled == 1)) { | |
1248 | pc = preempt_count(); | |
7be42151 | 1249 | __trace_graph_return(tr, trace, flags, pc); |
15e6cb36 | 1250 | } |
ea4e2bc4 SR |
1251 | if (!trace->depth) |
1252 | clear_tsk_trace_graph(current); | |
15e6cb36 | 1253 | atomic_dec(&data->disabled); |
a5e25883 | 1254 | local_irq_restore(flags); |
15e6cb36 | 1255 | } |
fb52607a | 1256 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
15e6cb36 | 1257 | |
769b0441 FW |
1258 | |
1259 | /** | |
48ead020 | 1260 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1261 | * |
1262 | */ | |
40ce74f1 | 1263 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1264 | { |
80370cb7 SR |
1265 | static raw_spinlock_t trace_buf_lock = |
1266 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
769b0441 FW |
1267 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1268 | ||
e1112b4d | 1269 | struct ftrace_event_call *call = &event_bprint; |
769b0441 FW |
1270 | struct ring_buffer_event *event; |
1271 | struct trace_array *tr = &global_trace; | |
1272 | struct trace_array_cpu *data; | |
48ead020 | 1273 | struct bprint_entry *entry; |
769b0441 | 1274 | unsigned long flags; |
3189cdb3 | 1275 | int disable; |
769b0441 FW |
1276 | int resched; |
1277 | int cpu, len = 0, size, pc; | |
1278 | ||
1279 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1280 | return 0; | |
1281 | ||
1282 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1283 | pause_graph_tracing(); | |
1284 | ||
1285 | pc = preempt_count(); | |
1286 | resched = ftrace_preempt_disable(); | |
1287 | cpu = raw_smp_processor_id(); | |
1288 | data = tr->data[cpu]; | |
1289 | ||
3189cdb3 SR |
1290 | disable = atomic_inc_return(&data->disabled); |
1291 | if (unlikely(disable != 1)) | |
769b0441 FW |
1292 | goto out; |
1293 | ||
80370cb7 SR |
1294 | /* Lockdep uses trace_printk for lock tracing */ |
1295 | local_irq_save(flags); | |
1296 | __raw_spin_lock(&trace_buf_lock); | |
769b0441 FW |
1297 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1298 | ||
1299 | if (len > TRACE_BUF_SIZE || len < 0) | |
1300 | goto out_unlock; | |
1301 | ||
1302 | size = sizeof(*entry) + sizeof(u32) * len; | |
48ead020 | 1303 | event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc); |
769b0441 FW |
1304 | if (!event) |
1305 | goto out_unlock; | |
1306 | entry = ring_buffer_event_data(event); | |
1307 | entry->ip = ip; | |
769b0441 FW |
1308 | entry->fmt = fmt; |
1309 | ||
1310 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
eb02ce01 TZ |
1311 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1312 | ring_buffer_unlock_commit(tr->buffer, event); | |
769b0441 FW |
1313 | |
1314 | out_unlock: | |
80370cb7 SR |
1315 | __raw_spin_unlock(&trace_buf_lock); |
1316 | local_irq_restore(flags); | |
769b0441 FW |
1317 | |
1318 | out: | |
3189cdb3 | 1319 | atomic_dec_return(&data->disabled); |
769b0441 FW |
1320 | ftrace_preempt_enable(resched); |
1321 | unpause_graph_tracing(); | |
1322 | ||
1323 | return len; | |
1324 | } | |
48ead020 FW |
1325 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1326 | ||
40ce74f1 | 1327 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
48ead020 FW |
1328 | { |
1329 | static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; | |
1330 | static char trace_buf[TRACE_BUF_SIZE]; | |
1331 | ||
e1112b4d | 1332 | struct ftrace_event_call *call = &event_print; |
48ead020 FW |
1333 | struct ring_buffer_event *event; |
1334 | struct trace_array *tr = &global_trace; | |
1335 | struct trace_array_cpu *data; | |
1336 | int cpu, len = 0, size, pc; | |
1337 | struct print_entry *entry; | |
1338 | unsigned long irq_flags; | |
3189cdb3 | 1339 | int disable; |
48ead020 FW |
1340 | |
1341 | if (tracing_disabled || tracing_selftest_running) | |
1342 | return 0; | |
1343 | ||
1344 | pc = preempt_count(); | |
1345 | preempt_disable_notrace(); | |
1346 | cpu = raw_smp_processor_id(); | |
1347 | data = tr->data[cpu]; | |
1348 | ||
3189cdb3 SR |
1349 | disable = atomic_inc_return(&data->disabled); |
1350 | if (unlikely(disable != 1)) | |
48ead020 FW |
1351 | goto out; |
1352 | ||
1353 | pause_graph_tracing(); | |
1354 | raw_local_irq_save(irq_flags); | |
1355 | __raw_spin_lock(&trace_buf_lock); | |
1356 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); | |
1357 | ||
1358 | len = min(len, TRACE_BUF_SIZE-1); | |
1359 | trace_buf[len] = 0; | |
1360 | ||
1361 | size = sizeof(*entry) + len + 1; | |
1362 | event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc); | |
1363 | if (!event) | |
1364 | goto out_unlock; | |
1365 | entry = ring_buffer_event_data(event); | |
1366 | entry->ip = ip; | |
48ead020 FW |
1367 | |
1368 | memcpy(&entry->buf, trace_buf, len); | |
1369 | entry->buf[len] = 0; | |
eb02ce01 TZ |
1370 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1371 | ring_buffer_unlock_commit(tr->buffer, event); | |
48ead020 FW |
1372 | |
1373 | out_unlock: | |
1374 | __raw_spin_unlock(&trace_buf_lock); | |
1375 | raw_local_irq_restore(irq_flags); | |
1376 | unpause_graph_tracing(); | |
1377 | out: | |
3189cdb3 | 1378 | atomic_dec_return(&data->disabled); |
48ead020 FW |
1379 | preempt_enable_notrace(); |
1380 | ||
1381 | return len; | |
1382 | } | |
769b0441 FW |
1383 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1384 | ||
bc0c38d1 SR |
1385 | enum trace_file_type { |
1386 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1387 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1388 | }; |
1389 | ||
e2ac8ef5 | 1390 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1391 | { |
d769041f SR |
1392 | /* Don't allow ftrace to trace into the ring buffers */ |
1393 | ftrace_disable_cpu(); | |
1394 | ||
5a90f577 | 1395 | iter->idx++; |
d769041f SR |
1396 | if (iter->buffer_iter[iter->cpu]) |
1397 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1398 | ||
1399 | ftrace_enable_cpu(); | |
5a90f577 SR |
1400 | } |
1401 | ||
e309b41d | 1402 | static struct trace_entry * |
3928a8a2 | 1403 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1404 | { |
3928a8a2 SR |
1405 | struct ring_buffer_event *event; |
1406 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1407 | |
d769041f SR |
1408 | /* Don't allow ftrace to trace into the ring buffers */ |
1409 | ftrace_disable_cpu(); | |
1410 | ||
1411 | if (buf_iter) | |
1412 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1413 | else | |
1414 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1415 | ||
1416 | ftrace_enable_cpu(); | |
1417 | ||
3928a8a2 | 1418 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1419 | } |
d769041f | 1420 | |
dd0e545f | 1421 | static struct trace_entry * |
3928a8a2 | 1422 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1423 | { |
3928a8a2 | 1424 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1425 | struct trace_entry *ent, *next = NULL; |
b04cc6b1 | 1426 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1427 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1428 | int next_cpu = -1; |
1429 | int cpu; | |
1430 | ||
b04cc6b1 FW |
1431 | /* |
1432 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1433 | * all cpu and peek directly. | |
1434 | */ | |
1435 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1436 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1437 | return NULL; | |
1438 | ent = peek_next_entry(iter, cpu_file, ent_ts); | |
1439 | if (ent_cpu) | |
1440 | *ent_cpu = cpu_file; | |
1441 | ||
1442 | return ent; | |
1443 | } | |
1444 | ||
ab46428c | 1445 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1446 | |
3928a8a2 SR |
1447 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1448 | continue; | |
dd0e545f | 1449 | |
3928a8a2 | 1450 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1451 | |
cdd31cd2 IM |
1452 | /* |
1453 | * Pick the entry with the smallest timestamp: | |
1454 | */ | |
3928a8a2 | 1455 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1456 | next = ent; |
1457 | next_cpu = cpu; | |
3928a8a2 | 1458 | next_ts = ts; |
bc0c38d1 SR |
1459 | } |
1460 | } | |
1461 | ||
1462 | if (ent_cpu) | |
1463 | *ent_cpu = next_cpu; | |
1464 | ||
3928a8a2 SR |
1465 | if (ent_ts) |
1466 | *ent_ts = next_ts; | |
1467 | ||
bc0c38d1 SR |
1468 | return next; |
1469 | } | |
1470 | ||
dd0e545f | 1471 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1472 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1473 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1474 | { |
3928a8a2 | 1475 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1476 | } |
1477 | ||
1478 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1479 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1480 | { | |
3928a8a2 | 1481 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1482 | |
3928a8a2 | 1483 | if (iter->ent) |
e2ac8ef5 | 1484 | trace_iterator_increment(iter); |
dd0e545f | 1485 | |
3928a8a2 | 1486 | return iter->ent ? iter : NULL; |
b3806b43 | 1487 | } |
bc0c38d1 | 1488 | |
e309b41d | 1489 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1490 | { |
d769041f SR |
1491 | /* Don't allow ftrace to trace into the ring buffers */ |
1492 | ftrace_disable_cpu(); | |
3928a8a2 | 1493 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1494 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1495 | } |
1496 | ||
e309b41d | 1497 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1498 | { |
1499 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1500 | int i = (int)*pos; |
4e3c3333 | 1501 | void *ent; |
bc0c38d1 SR |
1502 | |
1503 | (*pos)++; | |
1504 | ||
1505 | /* can't go backwards */ | |
1506 | if (iter->idx > i) | |
1507 | return NULL; | |
1508 | ||
1509 | if (iter->idx < 0) | |
1510 | ent = find_next_entry_inc(iter); | |
1511 | else | |
1512 | ent = iter; | |
1513 | ||
1514 | while (ent && iter->idx < i) | |
1515 | ent = find_next_entry_inc(iter); | |
1516 | ||
1517 | iter->pos = *pos; | |
1518 | ||
bc0c38d1 SR |
1519 | return ent; |
1520 | } | |
1521 | ||
d7350c3f FW |
1522 | /* |
1523 | * No necessary locking here. The worst thing which can | |
1524 | * happen is loosing events consumed at the same time | |
1525 | * by a trace_pipe reader. | |
1526 | * Other than that, we don't risk to crash the ring buffer | |
1527 | * because it serializes the readers. | |
1528 | * | |
1529 | * The current tracer is copied to avoid a global locking | |
1530 | * all around. | |
1531 | */ | |
bc0c38d1 SR |
1532 | static void *s_start(struct seq_file *m, loff_t *pos) |
1533 | { | |
1534 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1535 | static struct tracer *old_tracer; |
b04cc6b1 | 1536 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1537 | void *p = NULL; |
1538 | loff_t l = 0; | |
3928a8a2 | 1539 | int cpu; |
bc0c38d1 | 1540 | |
d7350c3f | 1541 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1542 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1543 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1544 | old_tracer = current_trace; | |
1545 | *iter->trace = *current_trace; | |
d15f57f2 | 1546 | } |
d7350c3f | 1547 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1548 | |
1549 | atomic_inc(&trace_record_cmdline_disabled); | |
1550 | ||
bc0c38d1 SR |
1551 | if (*pos != iter->pos) { |
1552 | iter->ent = NULL; | |
1553 | iter->cpu = 0; | |
1554 | iter->idx = -1; | |
1555 | ||
d769041f SR |
1556 | ftrace_disable_cpu(); |
1557 | ||
b04cc6b1 FW |
1558 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1559 | for_each_tracing_cpu(cpu) | |
1560 | ring_buffer_iter_reset(iter->buffer_iter[cpu]); | |
1561 | } else | |
1562 | ring_buffer_iter_reset(iter->buffer_iter[cpu_file]); | |
1563 | ||
bc0c38d1 | 1564 | |
d769041f SR |
1565 | ftrace_enable_cpu(); |
1566 | ||
bc0c38d1 SR |
1567 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1568 | ; | |
1569 | ||
1570 | } else { | |
4c11d7ae | 1571 | l = *pos - 1; |
bc0c38d1 SR |
1572 | p = s_next(m, p, &l); |
1573 | } | |
1574 | ||
4f535968 | 1575 | trace_event_read_lock(); |
bc0c38d1 SR |
1576 | return p; |
1577 | } | |
1578 | ||
1579 | static void s_stop(struct seq_file *m, void *p) | |
1580 | { | |
bc0c38d1 | 1581 | atomic_dec(&trace_record_cmdline_disabled); |
4f535968 | 1582 | trace_event_read_unlock(); |
bc0c38d1 SR |
1583 | } |
1584 | ||
e309b41d | 1585 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1586 | { |
a6168353 ME |
1587 | seq_puts(m, "# _------=> CPU# \n"); |
1588 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1589 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1590 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1591 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1592 | seq_puts(m, "# |||| / \n"); | |
1593 | seq_puts(m, "# ||||| delay \n"); | |
1594 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1595 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1596 | } |
1597 | ||
e309b41d | 1598 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1599 | { |
a6168353 ME |
1600 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1601 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1602 | } |
1603 | ||
1604 | ||
e309b41d | 1605 | static void |
bc0c38d1 SR |
1606 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1607 | { | |
1608 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1609 | struct trace_array *tr = iter->tr; | |
1610 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1611 | struct tracer *type = current_trace; | |
3928a8a2 SR |
1612 | unsigned long total; |
1613 | unsigned long entries; | |
bc0c38d1 SR |
1614 | const char *name = "preemption"; |
1615 | ||
1616 | if (type) | |
1617 | name = type->name; | |
1618 | ||
3928a8a2 SR |
1619 | entries = ring_buffer_entries(iter->tr->buffer); |
1620 | total = entries + | |
1621 | ring_buffer_overruns(iter->tr->buffer); | |
bc0c38d1 | 1622 | |
888b55dc | 1623 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1624 | name, UTS_RELEASE); |
888b55dc | 1625 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1626 | "---------------------------------\n"); |
888b55dc | 1627 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1628 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1629 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1630 | entries, |
4c11d7ae | 1631 | total, |
bc0c38d1 SR |
1632 | tr->cpu, |
1633 | #if defined(CONFIG_PREEMPT_NONE) | |
1634 | "server", | |
1635 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1636 | "desktop", | |
b5c21b45 | 1637 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1638 | "preempt", |
1639 | #else | |
1640 | "unknown", | |
1641 | #endif | |
1642 | /* These are reserved for later use */ | |
1643 | 0, 0, 0, 0); | |
1644 | #ifdef CONFIG_SMP | |
1645 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1646 | #else | |
1647 | seq_puts(m, ")\n"); | |
1648 | #endif | |
888b55dc KM |
1649 | seq_puts(m, "# -----------------\n"); |
1650 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1651 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1652 | data->comm, data->pid, data->uid, data->nice, | |
1653 | data->policy, data->rt_priority); | |
888b55dc | 1654 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1655 | |
1656 | if (data->critical_start) { | |
888b55dc | 1657 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1658 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1659 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1660 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1661 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1662 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1663 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1664 | } |
1665 | ||
888b55dc | 1666 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1667 | } |
1668 | ||
a309720c SR |
1669 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1670 | { | |
1671 | struct trace_seq *s = &iter->seq; | |
1672 | ||
12ef7d44 SR |
1673 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1674 | return; | |
1675 | ||
1676 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1677 | return; | |
1678 | ||
4462344e | 1679 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1680 | return; |
1681 | ||
4462344e | 1682 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1683 | |
1684 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1685 | if (iter->idx > 1) | |
1686 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1687 | iter->cpu); | |
a309720c SR |
1688 | } |
1689 | ||
2c4f035f | 1690 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1691 | { |
214023c3 | 1692 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1693 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1694 | struct trace_entry *entry; |
f633cef0 | 1695 | struct trace_event *event; |
bc0c38d1 | 1696 | |
4e3c3333 | 1697 | entry = iter->ent; |
dd0e545f | 1698 | |
a309720c SR |
1699 | test_cpu_buff_start(iter); |
1700 | ||
c4a8e8be | 1701 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1702 | |
c4a8e8be | 1703 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1704 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1705 | if (!trace_print_lat_context(iter)) | |
1706 | goto partial; | |
1707 | } else { | |
1708 | if (!trace_print_context(iter)) | |
1709 | goto partial; | |
1710 | } | |
c4a8e8be | 1711 | } |
bc0c38d1 | 1712 | |
268ccda0 | 1713 | if (event) |
d9793bd8 ACM |
1714 | return event->trace(iter, sym_flags); |
1715 | ||
1716 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1717 | goto partial; | |
02b67518 | 1718 | |
2c4f035f | 1719 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1720 | partial: |
1721 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1722 | } |
1723 | ||
2c4f035f | 1724 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1725 | { |
1726 | struct trace_seq *s = &iter->seq; | |
1727 | struct trace_entry *entry; | |
f633cef0 | 1728 | struct trace_event *event; |
f9896bf3 IM |
1729 | |
1730 | entry = iter->ent; | |
dd0e545f | 1731 | |
c4a8e8be | 1732 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1733 | if (!trace_seq_printf(s, "%d %d %llu ", |
1734 | entry->pid, iter->cpu, iter->ts)) | |
1735 | goto partial; | |
c4a8e8be | 1736 | } |
f9896bf3 | 1737 | |
f633cef0 | 1738 | event = ftrace_find_event(entry->type); |
268ccda0 | 1739 | if (event) |
d9793bd8 ACM |
1740 | return event->raw(iter, 0); |
1741 | ||
1742 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1743 | goto partial; | |
777e208d | 1744 | |
2c4f035f | 1745 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1746 | partial: |
1747 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1748 | } |
1749 | ||
2c4f035f | 1750 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1751 | { |
1752 | struct trace_seq *s = &iter->seq; | |
1753 | unsigned char newline = '\n'; | |
1754 | struct trace_entry *entry; | |
f633cef0 | 1755 | struct trace_event *event; |
5e3ca0ec IM |
1756 | |
1757 | entry = iter->ent; | |
dd0e545f | 1758 | |
c4a8e8be FW |
1759 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1760 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1761 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1762 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1763 | } | |
5e3ca0ec | 1764 | |
f633cef0 | 1765 | event = ftrace_find_event(entry->type); |
268ccda0 | 1766 | if (event) { |
ae7462b4 | 1767 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1768 | if (ret != TRACE_TYPE_HANDLED) |
1769 | return ret; | |
1770 | } | |
7104f300 | 1771 | |
5e3ca0ec IM |
1772 | SEQ_PUT_FIELD_RET(s, newline); |
1773 | ||
2c4f035f | 1774 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1775 | } |
1776 | ||
2c4f035f | 1777 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1778 | { |
1779 | struct trace_seq *s = &iter->seq; | |
1780 | struct trace_entry *entry; | |
f633cef0 | 1781 | struct trace_event *event; |
cb0f12aa IM |
1782 | |
1783 | entry = iter->ent; | |
dd0e545f | 1784 | |
c4a8e8be FW |
1785 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1786 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1787 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1788 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1789 | } | |
cb0f12aa | 1790 | |
f633cef0 | 1791 | event = ftrace_find_event(entry->type); |
268ccda0 | 1792 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1793 | } |
1794 | ||
bc0c38d1 SR |
1795 | static int trace_empty(struct trace_iterator *iter) |
1796 | { | |
bc0c38d1 SR |
1797 | int cpu; |
1798 | ||
9aba60fe SR |
1799 | /* If we are looking at one CPU buffer, only check that one */ |
1800 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1801 | cpu = iter->cpu_file; | |
1802 | if (iter->buffer_iter[cpu]) { | |
1803 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1804 | return 0; | |
1805 | } else { | |
1806 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1807 | return 0; | |
1808 | } | |
1809 | return 1; | |
1810 | } | |
1811 | ||
ab46428c | 1812 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1813 | if (iter->buffer_iter[cpu]) { |
1814 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1815 | return 0; | |
1816 | } else { | |
1817 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1818 | return 0; | |
1819 | } | |
bc0c38d1 | 1820 | } |
d769041f | 1821 | |
797d3712 | 1822 | return 1; |
bc0c38d1 SR |
1823 | } |
1824 | ||
4f535968 | 1825 | /* Called with trace_event_read_lock() held. */ |
2c4f035f | 1826 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1827 | { |
2c4f035f FW |
1828 | enum print_line_t ret; |
1829 | ||
1830 | if (iter->trace && iter->trace->print_line) { | |
1831 | ret = iter->trace->print_line(iter); | |
1832 | if (ret != TRACE_TYPE_UNHANDLED) | |
1833 | return ret; | |
1834 | } | |
72829bc3 | 1835 | |
48ead020 FW |
1836 | if (iter->ent->type == TRACE_BPRINT && |
1837 | trace_flags & TRACE_ITER_PRINTK && | |
1838 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1839 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 1840 | |
66896a85 FW |
1841 | if (iter->ent->type == TRACE_PRINT && |
1842 | trace_flags & TRACE_ITER_PRINTK && | |
1843 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1844 | return trace_print_printk_msg_only(iter); |
66896a85 | 1845 | |
cb0f12aa IM |
1846 | if (trace_flags & TRACE_ITER_BIN) |
1847 | return print_bin_fmt(iter); | |
1848 | ||
5e3ca0ec IM |
1849 | if (trace_flags & TRACE_ITER_HEX) |
1850 | return print_hex_fmt(iter); | |
1851 | ||
f9896bf3 IM |
1852 | if (trace_flags & TRACE_ITER_RAW) |
1853 | return print_raw_fmt(iter); | |
1854 | ||
f9896bf3 IM |
1855 | return print_trace_fmt(iter); |
1856 | } | |
1857 | ||
bc0c38d1 SR |
1858 | static int s_show(struct seq_file *m, void *v) |
1859 | { | |
1860 | struct trace_iterator *iter = v; | |
1861 | ||
1862 | if (iter->ent == NULL) { | |
1863 | if (iter->tr) { | |
1864 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1865 | seq_puts(m, "#\n"); | |
1866 | } | |
8bba1bf5 MM |
1867 | if (iter->trace && iter->trace->print_header) |
1868 | iter->trace->print_header(m); | |
1869 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
1870 | /* print nothing if the buffers are empty */ |
1871 | if (trace_empty(iter)) | |
1872 | return 0; | |
1873 | print_trace_header(m, iter); | |
1874 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1875 | print_lat_help_header(m); | |
1876 | } else { | |
1877 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1878 | print_func_help_header(m); | |
1879 | } | |
1880 | } else { | |
f9896bf3 | 1881 | print_trace_line(iter); |
214023c3 | 1882 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1883 | } |
1884 | ||
1885 | return 0; | |
1886 | } | |
1887 | ||
1888 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1889 | .start = s_start, |
1890 | .next = s_next, | |
1891 | .stop = s_stop, | |
1892 | .show = s_show, | |
bc0c38d1 SR |
1893 | }; |
1894 | ||
e309b41d | 1895 | static struct trace_iterator * |
85a2f9b4 | 1896 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 1897 | { |
b04cc6b1 | 1898 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 1899 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 1900 | struct trace_iterator *iter; |
3928a8a2 | 1901 | struct seq_file *m; |
85a2f9b4 | 1902 | int cpu, ret; |
bc0c38d1 | 1903 | |
85a2f9b4 SR |
1904 | if (tracing_disabled) |
1905 | return ERR_PTR(-ENODEV); | |
60a11774 | 1906 | |
bc0c38d1 | 1907 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
1908 | if (!iter) |
1909 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 1910 | |
d7350c3f FW |
1911 | /* |
1912 | * We make a copy of the current tracer to avoid concurrent | |
1913 | * changes on it while we are reading. | |
1914 | */ | |
bc0c38d1 | 1915 | mutex_lock(&trace_types_lock); |
d7350c3f | 1916 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 1917 | if (!iter->trace) |
d7350c3f | 1918 | goto fail; |
85a2f9b4 | 1919 | |
d7350c3f FW |
1920 | if (current_trace) |
1921 | *iter->trace = *current_trace; | |
1922 | ||
b0dfa978 FW |
1923 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) |
1924 | goto fail; | |
1925 | ||
1926 | cpumask_clear(iter->started); | |
1927 | ||
bc0c38d1 SR |
1928 | if (current_trace && current_trace->print_max) |
1929 | iter->tr = &max_tr; | |
1930 | else | |
b04cc6b1 | 1931 | iter->tr = &global_trace; |
bc0c38d1 | 1932 | iter->pos = -1; |
d7350c3f | 1933 | mutex_init(&iter->mutex); |
b04cc6b1 | 1934 | iter->cpu_file = cpu_file; |
bc0c38d1 | 1935 | |
8bba1bf5 MM |
1936 | /* Notify the tracer early; before we stop tracing. */ |
1937 | if (iter->trace && iter->trace->open) | |
a93751ca | 1938 | iter->trace->open(iter); |
8bba1bf5 | 1939 | |
12ef7d44 SR |
1940 | /* Annotate start of buffers if we had overruns */ |
1941 | if (ring_buffer_overruns(iter->tr->buffer)) | |
1942 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
1943 | ||
b04cc6b1 FW |
1944 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
1945 | for_each_tracing_cpu(cpu) { | |
12ef7d44 | 1946 | |
b04cc6b1 FW |
1947 | iter->buffer_iter[cpu] = |
1948 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
b04cc6b1 FW |
1949 | } |
1950 | } else { | |
1951 | cpu = iter->cpu_file; | |
3928a8a2 | 1952 | iter->buffer_iter[cpu] = |
b04cc6b1 | 1953 | ring_buffer_read_start(iter->tr->buffer, cpu); |
3928a8a2 SR |
1954 | } |
1955 | ||
bc0c38d1 | 1956 | /* TODO stop tracer */ |
85a2f9b4 SR |
1957 | ret = seq_open(file, &tracer_seq_ops); |
1958 | if (ret < 0) { | |
1959 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 1960 | goto fail_buffer; |
85a2f9b4 | 1961 | } |
bc0c38d1 | 1962 | |
3928a8a2 SR |
1963 | m = file->private_data; |
1964 | m->private = iter; | |
bc0c38d1 | 1965 | |
3928a8a2 | 1966 | /* stop the trace while dumping */ |
9036990d | 1967 | tracing_stop(); |
3928a8a2 | 1968 | |
bc0c38d1 SR |
1969 | mutex_unlock(&trace_types_lock); |
1970 | ||
bc0c38d1 | 1971 | return iter; |
3928a8a2 SR |
1972 | |
1973 | fail_buffer: | |
1974 | for_each_tracing_cpu(cpu) { | |
1975 | if (iter->buffer_iter[cpu]) | |
1976 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1977 | } | |
b0dfa978 | 1978 | free_cpumask_var(iter->started); |
d7350c3f | 1979 | fail: |
3928a8a2 | 1980 | mutex_unlock(&trace_types_lock); |
d7350c3f | 1981 | kfree(iter->trace); |
0bb943c7 | 1982 | kfree(iter); |
3928a8a2 | 1983 | |
85a2f9b4 | 1984 | return fail_ret; |
bc0c38d1 SR |
1985 | } |
1986 | ||
1987 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1988 | { | |
60a11774 SR |
1989 | if (tracing_disabled) |
1990 | return -ENODEV; | |
1991 | ||
bc0c38d1 SR |
1992 | filp->private_data = inode->i_private; |
1993 | return 0; | |
1994 | } | |
1995 | ||
4fd27358 | 1996 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
1997 | { |
1998 | struct seq_file *m = (struct seq_file *)file->private_data; | |
4acd4d00 | 1999 | struct trace_iterator *iter; |
3928a8a2 | 2000 | int cpu; |
bc0c38d1 | 2001 | |
4acd4d00 SR |
2002 | if (!(file->f_mode & FMODE_READ)) |
2003 | return 0; | |
2004 | ||
2005 | iter = m->private; | |
2006 | ||
bc0c38d1 | 2007 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
2008 | for_each_tracing_cpu(cpu) { |
2009 | if (iter->buffer_iter[cpu]) | |
2010 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
2011 | } | |
2012 | ||
bc0c38d1 SR |
2013 | if (iter->trace && iter->trace->close) |
2014 | iter->trace->close(iter); | |
2015 | ||
2016 | /* reenable tracing if it was previously enabled */ | |
9036990d | 2017 | tracing_start(); |
bc0c38d1 SR |
2018 | mutex_unlock(&trace_types_lock); |
2019 | ||
2020 | seq_release(inode, file); | |
d7350c3f | 2021 | mutex_destroy(&iter->mutex); |
b0dfa978 | 2022 | free_cpumask_var(iter->started); |
d7350c3f | 2023 | kfree(iter->trace); |
bc0c38d1 SR |
2024 | kfree(iter); |
2025 | return 0; | |
2026 | } | |
2027 | ||
2028 | static int tracing_open(struct inode *inode, struct file *file) | |
2029 | { | |
85a2f9b4 SR |
2030 | struct trace_iterator *iter; |
2031 | int ret = 0; | |
bc0c38d1 | 2032 | |
4acd4d00 SR |
2033 | /* If this file was open for write, then erase contents */ |
2034 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 2035 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 2036 | long cpu = (long) inode->i_private; |
bc0c38d1 | 2037 | |
4acd4d00 SR |
2038 | if (cpu == TRACE_PIPE_ALL_CPU) |
2039 | tracing_reset_online_cpus(&global_trace); | |
2040 | else | |
2041 | tracing_reset(&global_trace, cpu); | |
2042 | } | |
bc0c38d1 | 2043 | |
4acd4d00 SR |
2044 | if (file->f_mode & FMODE_READ) { |
2045 | iter = __tracing_open(inode, file); | |
2046 | if (IS_ERR(iter)) | |
2047 | ret = PTR_ERR(iter); | |
2048 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
2049 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2050 | } | |
bc0c38d1 SR |
2051 | return ret; |
2052 | } | |
2053 | ||
e309b41d | 2054 | static void * |
bc0c38d1 SR |
2055 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2056 | { | |
f129e965 | 2057 | struct tracer *t = v; |
bc0c38d1 SR |
2058 | |
2059 | (*pos)++; | |
2060 | ||
2061 | if (t) | |
2062 | t = t->next; | |
2063 | ||
bc0c38d1 SR |
2064 | return t; |
2065 | } | |
2066 | ||
2067 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2068 | { | |
f129e965 | 2069 | struct tracer *t; |
bc0c38d1 SR |
2070 | loff_t l = 0; |
2071 | ||
2072 | mutex_lock(&trace_types_lock); | |
f129e965 | 2073 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
2074 | ; |
2075 | ||
2076 | return t; | |
2077 | } | |
2078 | ||
2079 | static void t_stop(struct seq_file *m, void *p) | |
2080 | { | |
2081 | mutex_unlock(&trace_types_lock); | |
2082 | } | |
2083 | ||
2084 | static int t_show(struct seq_file *m, void *v) | |
2085 | { | |
2086 | struct tracer *t = v; | |
2087 | ||
2088 | if (!t) | |
2089 | return 0; | |
2090 | ||
2091 | seq_printf(m, "%s", t->name); | |
2092 | if (t->next) | |
2093 | seq_putc(m, ' '); | |
2094 | else | |
2095 | seq_putc(m, '\n'); | |
2096 | ||
2097 | return 0; | |
2098 | } | |
2099 | ||
2100 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
2101 | .start = t_start, |
2102 | .next = t_next, | |
2103 | .stop = t_stop, | |
2104 | .show = t_show, | |
bc0c38d1 SR |
2105 | }; |
2106 | ||
2107 | static int show_traces_open(struct inode *inode, struct file *file) | |
2108 | { | |
60a11774 SR |
2109 | if (tracing_disabled) |
2110 | return -ENODEV; | |
2111 | ||
f129e965 | 2112 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2113 | } |
2114 | ||
4acd4d00 SR |
2115 | static ssize_t |
2116 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2117 | size_t count, loff_t *ppos) | |
2118 | { | |
2119 | return count; | |
2120 | } | |
2121 | ||
5e2336a0 | 2122 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2123 | .open = tracing_open, |
2124 | .read = seq_read, | |
4acd4d00 | 2125 | .write = tracing_write_stub, |
4bf39a94 IM |
2126 | .llseek = seq_lseek, |
2127 | .release = tracing_release, | |
bc0c38d1 SR |
2128 | }; |
2129 | ||
5e2336a0 | 2130 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2131 | .open = show_traces_open, |
2132 | .read = seq_read, | |
2133 | .release = seq_release, | |
2134 | }; | |
2135 | ||
36dfe925 IM |
2136 | /* |
2137 | * Only trace on a CPU if the bitmask is set: | |
2138 | */ | |
9e01c1b7 | 2139 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2140 | |
2141 | /* | |
2142 | * The tracer itself will not take this lock, but still we want | |
2143 | * to provide a consistent cpumask to user-space: | |
2144 | */ | |
2145 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2146 | ||
2147 | /* | |
2148 | * Temporary storage for the character representation of the | |
2149 | * CPU bitmask (and one more byte for the newline): | |
2150 | */ | |
2151 | static char mask_str[NR_CPUS + 1]; | |
2152 | ||
c7078de1 IM |
2153 | static ssize_t |
2154 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2155 | size_t count, loff_t *ppos) | |
2156 | { | |
36dfe925 | 2157 | int len; |
c7078de1 IM |
2158 | |
2159 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2160 | |
9e01c1b7 | 2161 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2162 | if (count - len < 2) { |
2163 | count = -EINVAL; | |
2164 | goto out_err; | |
2165 | } | |
2166 | len += sprintf(mask_str + len, "\n"); | |
2167 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2168 | ||
2169 | out_err: | |
c7078de1 IM |
2170 | mutex_unlock(&tracing_cpumask_update_lock); |
2171 | ||
2172 | return count; | |
2173 | } | |
2174 | ||
2175 | static ssize_t | |
2176 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2177 | size_t count, loff_t *ppos) | |
2178 | { | |
36dfe925 | 2179 | int err, cpu; |
9e01c1b7 RR |
2180 | cpumask_var_t tracing_cpumask_new; |
2181 | ||
2182 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2183 | return -ENOMEM; | |
c7078de1 | 2184 | |
9e01c1b7 | 2185 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2186 | if (err) |
36dfe925 IM |
2187 | goto err_unlock; |
2188 | ||
215368e8 LZ |
2189 | mutex_lock(&tracing_cpumask_update_lock); |
2190 | ||
a5e25883 | 2191 | local_irq_disable(); |
92205c23 | 2192 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 2193 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2194 | /* |
2195 | * Increase/decrease the disabled counter if we are | |
2196 | * about to flip a bit in the cpumask: | |
2197 | */ | |
9e01c1b7 RR |
2198 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2199 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2200 | atomic_inc(&global_trace.data[cpu]->disabled); |
2201 | } | |
9e01c1b7 RR |
2202 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2203 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2204 | atomic_dec(&global_trace.data[cpu]->disabled); |
2205 | } | |
2206 | } | |
92205c23 | 2207 | __raw_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2208 | local_irq_enable(); |
36dfe925 | 2209 | |
9e01c1b7 | 2210 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2211 | |
2212 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2213 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2214 | |
2215 | return count; | |
36dfe925 IM |
2216 | |
2217 | err_unlock: | |
215368e8 | 2218 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2219 | |
2220 | return err; | |
c7078de1 IM |
2221 | } |
2222 | ||
5e2336a0 | 2223 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2224 | .open = tracing_open_generic, |
2225 | .read = tracing_cpumask_read, | |
2226 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2227 | }; |
2228 | ||
2229 | static ssize_t | |
ee6bce52 | 2230 | tracing_trace_options_read(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
2231 | size_t cnt, loff_t *ppos) |
2232 | { | |
d8e83d26 SR |
2233 | struct tracer_opt *trace_opts; |
2234 | u32 tracer_flags; | |
2235 | int len = 0; | |
bc0c38d1 SR |
2236 | char *buf; |
2237 | int r = 0; | |
d8e83d26 | 2238 | int i; |
adf9f195 | 2239 | |
bc0c38d1 | 2240 | |
c3706f00 | 2241 | /* calculate max size */ |
bc0c38d1 SR |
2242 | for (i = 0; trace_options[i]; i++) { |
2243 | len += strlen(trace_options[i]); | |
5c6a3ae1 | 2244 | len += 3; /* "no" and newline */ |
bc0c38d1 SR |
2245 | } |
2246 | ||
d8e83d26 SR |
2247 | mutex_lock(&trace_types_lock); |
2248 | tracer_flags = current_trace->flags->val; | |
2249 | trace_opts = current_trace->flags->opts; | |
2250 | ||
adf9f195 FW |
2251 | /* |
2252 | * Increase the size with names of options specific | |
2253 | * of the current tracer. | |
2254 | */ | |
2255 | for (i = 0; trace_opts[i].name; i++) { | |
2256 | len += strlen(trace_opts[i].name); | |
5c6a3ae1 | 2257 | len += 3; /* "no" and newline */ |
adf9f195 FW |
2258 | } |
2259 | ||
bc0c38d1 SR |
2260 | /* +2 for \n and \0 */ |
2261 | buf = kmalloc(len + 2, GFP_KERNEL); | |
d8e83d26 SR |
2262 | if (!buf) { |
2263 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 2264 | return -ENOMEM; |
d8e83d26 | 2265 | } |
bc0c38d1 SR |
2266 | |
2267 | for (i = 0; trace_options[i]; i++) { | |
2268 | if (trace_flags & (1 << i)) | |
5c6a3ae1 | 2269 | r += sprintf(buf + r, "%s\n", trace_options[i]); |
bc0c38d1 | 2270 | else |
5c6a3ae1 | 2271 | r += sprintf(buf + r, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2272 | } |
2273 | ||
adf9f195 FW |
2274 | for (i = 0; trace_opts[i].name; i++) { |
2275 | if (tracer_flags & trace_opts[i].bit) | |
5c6a3ae1 | 2276 | r += sprintf(buf + r, "%s\n", |
adf9f195 FW |
2277 | trace_opts[i].name); |
2278 | else | |
5c6a3ae1 | 2279 | r += sprintf(buf + r, "no%s\n", |
adf9f195 FW |
2280 | trace_opts[i].name); |
2281 | } | |
d8e83d26 | 2282 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2283 | |
bc0c38d1 SR |
2284 | WARN_ON(r >= len + 2); |
2285 | ||
36dfe925 | 2286 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2287 | |
2288 | kfree(buf); | |
bc0c38d1 SR |
2289 | return r; |
2290 | } | |
2291 | ||
adf9f195 FW |
2292 | /* Try to assign a tracer specific option */ |
2293 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2294 | { | |
2295 | struct tracer_flags *trace_flags = trace->flags; | |
2296 | struct tracer_opt *opts = NULL; | |
2297 | int ret = 0, i = 0; | |
2298 | int len; | |
2299 | ||
2300 | for (i = 0; trace_flags->opts[i].name; i++) { | |
2301 | opts = &trace_flags->opts[i]; | |
2302 | len = strlen(opts->name); | |
2303 | ||
2304 | if (strncmp(cmp, opts->name, len) == 0) { | |
2305 | ret = trace->set_flag(trace_flags->val, | |
2306 | opts->bit, !neg); | |
2307 | break; | |
2308 | } | |
2309 | } | |
2310 | /* Not found */ | |
2311 | if (!trace_flags->opts[i].name) | |
2312 | return -EINVAL; | |
2313 | ||
2314 | /* Refused to handle */ | |
2315 | if (ret) | |
2316 | return ret; | |
2317 | ||
2318 | if (neg) | |
2319 | trace_flags->val &= ~opts->bit; | |
2320 | else | |
2321 | trace_flags->val |= opts->bit; | |
2322 | ||
2323 | return 0; | |
2324 | } | |
2325 | ||
af4617bd SR |
2326 | static void set_tracer_flags(unsigned int mask, int enabled) |
2327 | { | |
2328 | /* do nothing if flag is already set */ | |
2329 | if (!!(trace_flags & mask) == !!enabled) | |
2330 | return; | |
2331 | ||
2332 | if (enabled) | |
2333 | trace_flags |= mask; | |
2334 | else | |
2335 | trace_flags &= ~mask; | |
2336 | ||
2337 | if (mask == TRACE_ITER_GLOBAL_CLK) { | |
2338 | u64 (*func)(void); | |
2339 | ||
2340 | if (enabled) | |
2341 | func = trace_clock_global; | |
2342 | else | |
2343 | func = trace_clock_local; | |
2344 | ||
2345 | mutex_lock(&trace_types_lock); | |
2346 | ring_buffer_set_clock(global_trace.buffer, func); | |
2347 | ||
2348 | if (max_tr.buffer) | |
2349 | ring_buffer_set_clock(max_tr.buffer, func); | |
2350 | mutex_unlock(&trace_types_lock); | |
2351 | } | |
2352 | } | |
2353 | ||
bc0c38d1 | 2354 | static ssize_t |
ee6bce52 | 2355 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2356 | size_t cnt, loff_t *ppos) |
2357 | { | |
2358 | char buf[64]; | |
2359 | char *cmp = buf; | |
2360 | int neg = 0; | |
adf9f195 | 2361 | int ret; |
bc0c38d1 SR |
2362 | int i; |
2363 | ||
cffae437 SR |
2364 | if (cnt >= sizeof(buf)) |
2365 | return -EINVAL; | |
bc0c38d1 SR |
2366 | |
2367 | if (copy_from_user(&buf, ubuf, cnt)) | |
2368 | return -EFAULT; | |
2369 | ||
2370 | buf[cnt] = 0; | |
2371 | ||
2372 | if (strncmp(buf, "no", 2) == 0) { | |
2373 | neg = 1; | |
2374 | cmp += 2; | |
2375 | } | |
2376 | ||
2377 | for (i = 0; trace_options[i]; i++) { | |
2378 | int len = strlen(trace_options[i]); | |
2379 | ||
2380 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
af4617bd | 2381 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2382 | break; |
2383 | } | |
2384 | } | |
adf9f195 FW |
2385 | |
2386 | /* If no option could be set, test the specific tracer options */ | |
2387 | if (!trace_options[i]) { | |
d8e83d26 | 2388 | mutex_lock(&trace_types_lock); |
adf9f195 | 2389 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2390 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2391 | if (ret) |
2392 | return ret; | |
2393 | } | |
bc0c38d1 SR |
2394 | |
2395 | filp->f_pos += cnt; | |
2396 | ||
2397 | return cnt; | |
2398 | } | |
2399 | ||
5e2336a0 | 2400 | static const struct file_operations tracing_iter_fops = { |
c7078de1 | 2401 | .open = tracing_open_generic, |
ee6bce52 SR |
2402 | .read = tracing_trace_options_read, |
2403 | .write = tracing_trace_options_write, | |
bc0c38d1 SR |
2404 | }; |
2405 | ||
7bd2f24c IM |
2406 | static const char readme_msg[] = |
2407 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2408 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2409 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
bc2b6871 | 2410 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
156f5a78 | 2411 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2412 | "nop\n" |
156f5a78 GL |
2413 | "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" |
2414 | "# cat /sys/kernel/debug/tracing/current_tracer\n" | |
7bd2f24c | 2415 | "sched_switch\n" |
156f5a78 | 2416 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2417 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 GL |
2418 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
2419 | "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
2420 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" | |
2421 | "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
7bd2f24c IM |
2422 | ; |
2423 | ||
2424 | static ssize_t | |
2425 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2426 | size_t cnt, loff_t *ppos) | |
2427 | { | |
2428 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2429 | readme_msg, strlen(readme_msg)); | |
2430 | } | |
2431 | ||
5e2336a0 | 2432 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2433 | .open = tracing_open_generic, |
2434 | .read = tracing_readme_read, | |
7bd2f24c IM |
2435 | }; |
2436 | ||
69abe6a5 AP |
2437 | static ssize_t |
2438 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2439 | size_t cnt, loff_t *ppos) | |
2440 | { | |
2441 | char *buf_comm; | |
2442 | char *file_buf; | |
2443 | char *buf; | |
2444 | int len = 0; | |
2445 | int pid; | |
2446 | int i; | |
2447 | ||
2448 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2449 | if (!file_buf) | |
2450 | return -ENOMEM; | |
2451 | ||
2452 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2453 | if (!buf_comm) { | |
2454 | kfree(file_buf); | |
2455 | return -ENOMEM; | |
2456 | } | |
2457 | ||
2458 | buf = file_buf; | |
2459 | ||
2460 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2461 | int r; | |
2462 | ||
2463 | pid = map_cmdline_to_pid[i]; | |
2464 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2465 | continue; | |
2466 | ||
2467 | trace_find_cmdline(pid, buf_comm); | |
2468 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2469 | buf += r; | |
2470 | len += r; | |
2471 | } | |
2472 | ||
2473 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2474 | file_buf, len); | |
2475 | ||
2476 | kfree(file_buf); | |
2477 | kfree(buf_comm); | |
2478 | ||
2479 | return len; | |
2480 | } | |
2481 | ||
2482 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2483 | .open = tracing_open_generic, | |
2484 | .read = tracing_saved_cmdlines_read, | |
2485 | }; | |
2486 | ||
bc0c38d1 SR |
2487 | static ssize_t |
2488 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2489 | size_t cnt, loff_t *ppos) | |
2490 | { | |
bc0c38d1 SR |
2491 | char buf[64]; |
2492 | int r; | |
2493 | ||
9036990d | 2494 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2495 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2496 | } |
2497 | ||
2498 | static ssize_t | |
2499 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2500 | size_t cnt, loff_t *ppos) | |
2501 | { | |
2502 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2503 | char buf[64]; |
5e39841c | 2504 | unsigned long val; |
c6caeeb1 | 2505 | int ret; |
bc0c38d1 | 2506 | |
cffae437 SR |
2507 | if (cnt >= sizeof(buf)) |
2508 | return -EINVAL; | |
bc0c38d1 SR |
2509 | |
2510 | if (copy_from_user(&buf, ubuf, cnt)) | |
2511 | return -EFAULT; | |
2512 | ||
2513 | buf[cnt] = 0; | |
2514 | ||
c6caeeb1 SR |
2515 | ret = strict_strtoul(buf, 10, &val); |
2516 | if (ret < 0) | |
2517 | return ret; | |
bc0c38d1 SR |
2518 | |
2519 | val = !!val; | |
2520 | ||
2521 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2522 | if (tracer_enabled ^ val) { |
2523 | if (val) { | |
bc0c38d1 | 2524 | tracer_enabled = 1; |
9036990d SR |
2525 | if (current_trace->start) |
2526 | current_trace->start(tr); | |
2527 | tracing_start(); | |
2528 | } else { | |
bc0c38d1 | 2529 | tracer_enabled = 0; |
9036990d SR |
2530 | tracing_stop(); |
2531 | if (current_trace->stop) | |
2532 | current_trace->stop(tr); | |
2533 | } | |
bc0c38d1 SR |
2534 | } |
2535 | mutex_unlock(&trace_types_lock); | |
2536 | ||
2537 | filp->f_pos += cnt; | |
2538 | ||
2539 | return cnt; | |
2540 | } | |
2541 | ||
2542 | static ssize_t | |
2543 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2544 | size_t cnt, loff_t *ppos) | |
2545 | { | |
2546 | char buf[max_tracer_type_len+2]; | |
2547 | int r; | |
2548 | ||
2549 | mutex_lock(&trace_types_lock); | |
2550 | if (current_trace) | |
2551 | r = sprintf(buf, "%s\n", current_trace->name); | |
2552 | else | |
2553 | r = sprintf(buf, "\n"); | |
2554 | mutex_unlock(&trace_types_lock); | |
2555 | ||
4bf39a94 | 2556 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2557 | } |
2558 | ||
b6f11df2 ACM |
2559 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2560 | { | |
2561 | tracing_reset_online_cpus(tr); | |
2562 | return t->init(tr); | |
2563 | } | |
2564 | ||
73c5162a SR |
2565 | static int tracing_resize_ring_buffer(unsigned long size) |
2566 | { | |
2567 | int ret; | |
2568 | ||
2569 | /* | |
2570 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2571 | * we use the size that was given, and we can forget about |
2572 | * expanding it later. | |
73c5162a SR |
2573 | */ |
2574 | ring_buffer_expanded = 1; | |
2575 | ||
2576 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2577 | if (ret < 0) | |
2578 | return ret; | |
2579 | ||
2580 | ret = ring_buffer_resize(max_tr.buffer, size); | |
2581 | if (ret < 0) { | |
2582 | int r; | |
2583 | ||
2584 | r = ring_buffer_resize(global_trace.buffer, | |
2585 | global_trace.entries); | |
2586 | if (r < 0) { | |
a123c52b SR |
2587 | /* |
2588 | * AARGH! We are left with different | |
2589 | * size max buffer!!!! | |
2590 | * The max buffer is our "snapshot" buffer. | |
2591 | * When a tracer needs a snapshot (one of the | |
2592 | * latency tracers), it swaps the max buffer | |
2593 | * with the saved snap shot. We succeeded to | |
2594 | * update the size of the main buffer, but failed to | |
2595 | * update the size of the max buffer. But when we tried | |
2596 | * to reset the main buffer to the original size, we | |
2597 | * failed there too. This is very unlikely to | |
2598 | * happen, but if it does, warn and kill all | |
2599 | * tracing. | |
2600 | */ | |
73c5162a SR |
2601 | WARN_ON(1); |
2602 | tracing_disabled = 1; | |
2603 | } | |
2604 | return ret; | |
2605 | } | |
2606 | ||
2607 | global_trace.entries = size; | |
2608 | ||
2609 | return ret; | |
2610 | } | |
2611 | ||
1852fcce SR |
2612 | /** |
2613 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2614 | * | |
2615 | * To save on memory when the tracing is never used on a system with it | |
2616 | * configured in. The ring buffers are set to a minimum size. But once | |
2617 | * a user starts to use the tracing facility, then they need to grow | |
2618 | * to their default size. | |
2619 | * | |
2620 | * This function is to be called when a tracer is about to be used. | |
2621 | */ | |
2622 | int tracing_update_buffers(void) | |
2623 | { | |
2624 | int ret = 0; | |
2625 | ||
1027fcb2 | 2626 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2627 | if (!ring_buffer_expanded) |
2628 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2629 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2630 | |
2631 | return ret; | |
2632 | } | |
2633 | ||
577b785f SR |
2634 | struct trace_option_dentry; |
2635 | ||
2636 | static struct trace_option_dentry * | |
2637 | create_trace_option_files(struct tracer *tracer); | |
2638 | ||
2639 | static void | |
2640 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2641 | ||
b2821ae6 | 2642 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2643 | { |
577b785f | 2644 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2645 | struct trace_array *tr = &global_trace; |
2646 | struct tracer *t; | |
d9e54076 | 2647 | int ret = 0; |
bc0c38d1 | 2648 | |
1027fcb2 SR |
2649 | mutex_lock(&trace_types_lock); |
2650 | ||
73c5162a SR |
2651 | if (!ring_buffer_expanded) { |
2652 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2653 | if (ret < 0) | |
59f586db | 2654 | goto out; |
73c5162a SR |
2655 | ret = 0; |
2656 | } | |
2657 | ||
bc0c38d1 SR |
2658 | for (t = trace_types; t; t = t->next) { |
2659 | if (strcmp(t->name, buf) == 0) | |
2660 | break; | |
2661 | } | |
c2931e05 FW |
2662 | if (!t) { |
2663 | ret = -EINVAL; | |
2664 | goto out; | |
2665 | } | |
2666 | if (t == current_trace) | |
bc0c38d1 SR |
2667 | goto out; |
2668 | ||
9f029e83 | 2669 | trace_branch_disable(); |
bc0c38d1 SR |
2670 | if (current_trace && current_trace->reset) |
2671 | current_trace->reset(tr); | |
2672 | ||
577b785f SR |
2673 | destroy_trace_option_files(topts); |
2674 | ||
bc0c38d1 | 2675 | current_trace = t; |
577b785f SR |
2676 | |
2677 | topts = create_trace_option_files(current_trace); | |
2678 | ||
1c80025a | 2679 | if (t->init) { |
b6f11df2 | 2680 | ret = tracer_init(t, tr); |
1c80025a FW |
2681 | if (ret) |
2682 | goto out; | |
2683 | } | |
bc0c38d1 | 2684 | |
9f029e83 | 2685 | trace_branch_enable(tr); |
bc0c38d1 SR |
2686 | out: |
2687 | mutex_unlock(&trace_types_lock); | |
2688 | ||
d9e54076 PZ |
2689 | return ret; |
2690 | } | |
2691 | ||
2692 | static ssize_t | |
2693 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2694 | size_t cnt, loff_t *ppos) | |
2695 | { | |
2696 | char buf[max_tracer_type_len+1]; | |
2697 | int i; | |
2698 | size_t ret; | |
e6e7a65a FW |
2699 | int err; |
2700 | ||
2701 | ret = cnt; | |
d9e54076 PZ |
2702 | |
2703 | if (cnt > max_tracer_type_len) | |
2704 | cnt = max_tracer_type_len; | |
2705 | ||
2706 | if (copy_from_user(&buf, ubuf, cnt)) | |
2707 | return -EFAULT; | |
2708 | ||
2709 | buf[cnt] = 0; | |
2710 | ||
2711 | /* strip ending whitespace. */ | |
2712 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2713 | buf[i] = 0; | |
2714 | ||
e6e7a65a FW |
2715 | err = tracing_set_tracer(buf); |
2716 | if (err) | |
2717 | return err; | |
d9e54076 | 2718 | |
e6e7a65a | 2719 | filp->f_pos += ret; |
bc0c38d1 | 2720 | |
c2931e05 | 2721 | return ret; |
bc0c38d1 SR |
2722 | } |
2723 | ||
2724 | static ssize_t | |
2725 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2726 | size_t cnt, loff_t *ppos) | |
2727 | { | |
2728 | unsigned long *ptr = filp->private_data; | |
2729 | char buf[64]; | |
2730 | int r; | |
2731 | ||
cffae437 | 2732 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2733 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2734 | if (r > sizeof(buf)) |
2735 | r = sizeof(buf); | |
4bf39a94 | 2736 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2737 | } |
2738 | ||
2739 | static ssize_t | |
2740 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2741 | size_t cnt, loff_t *ppos) | |
2742 | { | |
5e39841c | 2743 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2744 | char buf[64]; |
5e39841c | 2745 | unsigned long val; |
c6caeeb1 | 2746 | int ret; |
bc0c38d1 | 2747 | |
cffae437 SR |
2748 | if (cnt >= sizeof(buf)) |
2749 | return -EINVAL; | |
bc0c38d1 SR |
2750 | |
2751 | if (copy_from_user(&buf, ubuf, cnt)) | |
2752 | return -EFAULT; | |
2753 | ||
2754 | buf[cnt] = 0; | |
2755 | ||
c6caeeb1 SR |
2756 | ret = strict_strtoul(buf, 10, &val); |
2757 | if (ret < 0) | |
2758 | return ret; | |
bc0c38d1 SR |
2759 | |
2760 | *ptr = val * 1000; | |
2761 | ||
2762 | return cnt; | |
2763 | } | |
2764 | ||
b3806b43 SR |
2765 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2766 | { | |
b04cc6b1 | 2767 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2768 | struct trace_iterator *iter; |
b04cc6b1 | 2769 | int ret = 0; |
b3806b43 SR |
2770 | |
2771 | if (tracing_disabled) | |
2772 | return -ENODEV; | |
2773 | ||
b04cc6b1 FW |
2774 | mutex_lock(&trace_types_lock); |
2775 | ||
2776 | /* We only allow one reader per cpu */ | |
2777 | if (cpu_file == TRACE_PIPE_ALL_CPU) { | |
2778 | if (!cpumask_empty(tracing_reader_cpumask)) { | |
2779 | ret = -EBUSY; | |
2780 | goto out; | |
2781 | } | |
2782 | cpumask_setall(tracing_reader_cpumask); | |
2783 | } else { | |
2784 | if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask)) | |
2785 | cpumask_set_cpu(cpu_file, tracing_reader_cpumask); | |
2786 | else { | |
2787 | ret = -EBUSY; | |
2788 | goto out; | |
2789 | } | |
b3806b43 SR |
2790 | } |
2791 | ||
2792 | /* create a buffer to store the information to pass to userspace */ | |
2793 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2794 | if (!iter) { |
2795 | ret = -ENOMEM; | |
2796 | goto out; | |
2797 | } | |
b3806b43 | 2798 | |
d7350c3f FW |
2799 | /* |
2800 | * We make a copy of the current tracer to avoid concurrent | |
2801 | * changes on it while we are reading. | |
2802 | */ | |
2803 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
2804 | if (!iter->trace) { | |
2805 | ret = -ENOMEM; | |
2806 | goto fail; | |
2807 | } | |
2808 | if (current_trace) | |
2809 | *iter->trace = *current_trace; | |
2810 | ||
4462344e | 2811 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 2812 | ret = -ENOMEM; |
d7350c3f | 2813 | goto fail; |
4462344e RR |
2814 | } |
2815 | ||
a309720c | 2816 | /* trace pipe does not show start of buffer */ |
4462344e | 2817 | cpumask_setall(iter->started); |
a309720c | 2818 | |
112f38a7 SR |
2819 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
2820 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2821 | ||
b04cc6b1 | 2822 | iter->cpu_file = cpu_file; |
b3806b43 | 2823 | iter->tr = &global_trace; |
d7350c3f | 2824 | mutex_init(&iter->mutex); |
b3806b43 SR |
2825 | filp->private_data = iter; |
2826 | ||
107bad8b SR |
2827 | if (iter->trace->pipe_open) |
2828 | iter->trace->pipe_open(iter); | |
107bad8b | 2829 | |
b04cc6b1 FW |
2830 | out: |
2831 | mutex_unlock(&trace_types_lock); | |
2832 | return ret; | |
d7350c3f FW |
2833 | |
2834 | fail: | |
2835 | kfree(iter->trace); | |
2836 | kfree(iter); | |
2837 | mutex_unlock(&trace_types_lock); | |
2838 | return ret; | |
b3806b43 SR |
2839 | } |
2840 | ||
2841 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2842 | { | |
2843 | struct trace_iterator *iter = file->private_data; | |
2844 | ||
b04cc6b1 FW |
2845 | mutex_lock(&trace_types_lock); |
2846 | ||
2847 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) | |
2848 | cpumask_clear(tracing_reader_cpumask); | |
2849 | else | |
2850 | cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); | |
2851 | ||
2852 | mutex_unlock(&trace_types_lock); | |
2853 | ||
4462344e | 2854 | free_cpumask_var(iter->started); |
d7350c3f FW |
2855 | mutex_destroy(&iter->mutex); |
2856 | kfree(iter->trace); | |
b3806b43 | 2857 | kfree(iter); |
b3806b43 SR |
2858 | |
2859 | return 0; | |
2860 | } | |
2861 | ||
2a2cc8f7 SSP |
2862 | static unsigned int |
2863 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2864 | { | |
2865 | struct trace_iterator *iter = filp->private_data; | |
2866 | ||
2867 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2868 | /* | |
2869 | * Always select as readable when in blocking mode | |
2870 | */ | |
2871 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2872 | } else { |
2a2cc8f7 SSP |
2873 | if (!trace_empty(iter)) |
2874 | return POLLIN | POLLRDNORM; | |
2875 | poll_wait(filp, &trace_wait, poll_table); | |
2876 | if (!trace_empty(iter)) | |
2877 | return POLLIN | POLLRDNORM; | |
2878 | ||
2879 | return 0; | |
2880 | } | |
2881 | } | |
2882 | ||
6eaaa5d5 FW |
2883 | |
2884 | void default_wait_pipe(struct trace_iterator *iter) | |
2885 | { | |
2886 | DEFINE_WAIT(wait); | |
2887 | ||
2888 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
2889 | ||
2890 | if (trace_empty(iter)) | |
2891 | schedule(); | |
2892 | ||
2893 | finish_wait(&trace_wait, &wait); | |
2894 | } | |
2895 | ||
2896 | /* | |
2897 | * This is a make-shift waitqueue. | |
2898 | * A tracer might use this callback on some rare cases: | |
2899 | * | |
2900 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
2901 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
2902 | * 2) the function tracers, trace all functions, we don't want | |
2903 | * the overhead of calling wake_up and friends | |
2904 | * (and tracing them too) | |
2905 | * | |
2906 | * Anyway, this is really very primitive wakeup. | |
2907 | */ | |
2908 | void poll_wait_pipe(struct trace_iterator *iter) | |
2909 | { | |
2910 | set_current_state(TASK_INTERRUPTIBLE); | |
2911 | /* sleep for 100 msecs, and try again. */ | |
2912 | schedule_timeout(HZ / 10); | |
2913 | } | |
2914 | ||
ff98781b EGM |
2915 | /* Must be called with trace_types_lock mutex held. */ |
2916 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
2917 | { |
2918 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 2919 | |
b3806b43 | 2920 | while (trace_empty(iter)) { |
2dc8f095 | 2921 | |
107bad8b | 2922 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 2923 | return -EAGAIN; |
107bad8b | 2924 | } |
2dc8f095 | 2925 | |
d7350c3f | 2926 | mutex_unlock(&iter->mutex); |
107bad8b | 2927 | |
6eaaa5d5 | 2928 | iter->trace->wait_pipe(iter); |
b3806b43 | 2929 | |
d7350c3f | 2930 | mutex_lock(&iter->mutex); |
107bad8b | 2931 | |
6eaaa5d5 | 2932 | if (signal_pending(current)) |
ff98781b | 2933 | return -EINTR; |
b3806b43 SR |
2934 | |
2935 | /* | |
2936 | * We block until we read something and tracing is disabled. | |
2937 | * We still block if tracing is disabled, but we have never | |
2938 | * read anything. This allows a user to cat this file, and | |
2939 | * then enable tracing. But after we have read something, | |
2940 | * we give an EOF when tracing is again disabled. | |
2941 | * | |
2942 | * iter->pos will be 0 if we haven't read anything. | |
2943 | */ | |
2944 | if (!tracer_enabled && iter->pos) | |
2945 | break; | |
b3806b43 SR |
2946 | } |
2947 | ||
ff98781b EGM |
2948 | return 1; |
2949 | } | |
2950 | ||
2951 | /* | |
2952 | * Consumer reader. | |
2953 | */ | |
2954 | static ssize_t | |
2955 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2956 | size_t cnt, loff_t *ppos) | |
2957 | { | |
2958 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 2959 | static struct tracer *old_tracer; |
ff98781b EGM |
2960 | ssize_t sret; |
2961 | ||
2962 | /* return any leftover data */ | |
2963 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
2964 | if (sret != -EBUSY) | |
2965 | return sret; | |
2966 | ||
f9520750 | 2967 | trace_seq_init(&iter->seq); |
ff98781b | 2968 | |
d7350c3f | 2969 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 2970 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2971 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2972 | old_tracer = current_trace; | |
2973 | *iter->trace = *current_trace; | |
2974 | } | |
2975 | mutex_unlock(&trace_types_lock); | |
2976 | ||
2977 | /* | |
2978 | * Avoid more than one consumer on a single file descriptor | |
2979 | * This is just a matter of traces coherency, the ring buffer itself | |
2980 | * is protected. | |
2981 | */ | |
2982 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
2983 | if (iter->trace->read) { |
2984 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
2985 | if (sret) | |
2986 | goto out; | |
2987 | } | |
2988 | ||
2989 | waitagain: | |
2990 | sret = tracing_wait_pipe(filp); | |
2991 | if (sret <= 0) | |
2992 | goto out; | |
2993 | ||
b3806b43 | 2994 | /* stop when tracing is finished */ |
ff98781b EGM |
2995 | if (trace_empty(iter)) { |
2996 | sret = 0; | |
107bad8b | 2997 | goto out; |
ff98781b | 2998 | } |
b3806b43 SR |
2999 | |
3000 | if (cnt >= PAGE_SIZE) | |
3001 | cnt = PAGE_SIZE - 1; | |
3002 | ||
53d0aa77 | 3003 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
3004 | memset(&iter->seq, 0, |
3005 | sizeof(struct trace_iterator) - | |
3006 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 3007 | iter->pos = -1; |
b3806b43 | 3008 | |
4f535968 | 3009 | trace_event_read_lock(); |
088b1e42 | 3010 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 3011 | enum print_line_t ret; |
088b1e42 SR |
3012 | int len = iter->seq.len; |
3013 | ||
f9896bf3 | 3014 | ret = print_trace_line(iter); |
2c4f035f | 3015 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
3016 | /* don't print partial lines */ |
3017 | iter->seq.len = len; | |
b3806b43 | 3018 | break; |
088b1e42 | 3019 | } |
b91facc3 FW |
3020 | if (ret != TRACE_TYPE_NO_CONSUME) |
3021 | trace_consume(iter); | |
b3806b43 SR |
3022 | |
3023 | if (iter->seq.len >= cnt) | |
3024 | break; | |
b3806b43 | 3025 | } |
4f535968 | 3026 | trace_event_read_unlock(); |
b3806b43 | 3027 | |
b3806b43 | 3028 | /* Now copy what we have to the user */ |
6c6c2796 PP |
3029 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
3030 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 3031 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
3032 | |
3033 | /* | |
3034 | * If there was nothing to send to user, inspite of consuming trace | |
3035 | * entries, go back to wait for more entries. | |
3036 | */ | |
6c6c2796 | 3037 | if (sret == -EBUSY) |
9ff4b974 | 3038 | goto waitagain; |
b3806b43 | 3039 | |
107bad8b | 3040 | out: |
d7350c3f | 3041 | mutex_unlock(&iter->mutex); |
107bad8b | 3042 | |
6c6c2796 | 3043 | return sret; |
b3806b43 SR |
3044 | } |
3045 | ||
3c56819b EGM |
3046 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
3047 | struct pipe_buffer *buf) | |
3048 | { | |
3049 | __free_page(buf->page); | |
3050 | } | |
3051 | ||
3052 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
3053 | unsigned int idx) | |
3054 | { | |
3055 | __free_page(spd->pages[idx]); | |
3056 | } | |
3057 | ||
3058 | static struct pipe_buf_operations tracing_pipe_buf_ops = { | |
34cd4998 SR |
3059 | .can_merge = 0, |
3060 | .map = generic_pipe_buf_map, | |
3061 | .unmap = generic_pipe_buf_unmap, | |
3062 | .confirm = generic_pipe_buf_confirm, | |
3063 | .release = tracing_pipe_buf_release, | |
3064 | .steal = generic_pipe_buf_steal, | |
3065 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
3066 | }; |
3067 | ||
34cd4998 | 3068 | static size_t |
fa7c7f6e | 3069 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
3070 | { |
3071 | size_t count; | |
3072 | int ret; | |
3073 | ||
3074 | /* Seq buffer is page-sized, exactly what we need. */ | |
3075 | for (;;) { | |
3076 | count = iter->seq.len; | |
3077 | ret = print_trace_line(iter); | |
3078 | count = iter->seq.len - count; | |
3079 | if (rem < count) { | |
3080 | rem = 0; | |
3081 | iter->seq.len -= count; | |
3082 | break; | |
3083 | } | |
3084 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
3085 | iter->seq.len -= count; | |
3086 | break; | |
3087 | } | |
3088 | ||
74e7ff8c LJ |
3089 | if (ret != TRACE_TYPE_NO_CONSUME) |
3090 | trace_consume(iter); | |
34cd4998 SR |
3091 | rem -= count; |
3092 | if (!find_next_entry_inc(iter)) { | |
3093 | rem = 0; | |
3094 | iter->ent = NULL; | |
3095 | break; | |
3096 | } | |
3097 | } | |
3098 | ||
3099 | return rem; | |
3100 | } | |
3101 | ||
3c56819b EGM |
3102 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3103 | loff_t *ppos, | |
3104 | struct pipe_inode_info *pipe, | |
3105 | size_t len, | |
3106 | unsigned int flags) | |
3107 | { | |
3108 | struct page *pages[PIPE_BUFFERS]; | |
3109 | struct partial_page partial[PIPE_BUFFERS]; | |
3110 | struct trace_iterator *iter = filp->private_data; | |
3111 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
3112 | .pages = pages, |
3113 | .partial = partial, | |
3114 | .nr_pages = 0, /* This gets updated below. */ | |
3115 | .flags = flags, | |
3116 | .ops = &tracing_pipe_buf_ops, | |
3117 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3118 | }; |
d7350c3f | 3119 | static struct tracer *old_tracer; |
3c56819b | 3120 | ssize_t ret; |
34cd4998 | 3121 | size_t rem; |
3c56819b EGM |
3122 | unsigned int i; |
3123 | ||
d7350c3f | 3124 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3125 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3126 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3127 | old_tracer = current_trace; | |
3128 | *iter->trace = *current_trace; | |
3129 | } | |
3130 | mutex_unlock(&trace_types_lock); | |
3131 | ||
3132 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3133 | |
3134 | if (iter->trace->splice_read) { | |
3135 | ret = iter->trace->splice_read(iter, filp, | |
3136 | ppos, pipe, len, flags); | |
3137 | if (ret) | |
34cd4998 | 3138 | goto out_err; |
3c56819b EGM |
3139 | } |
3140 | ||
3141 | ret = tracing_wait_pipe(filp); | |
3142 | if (ret <= 0) | |
34cd4998 | 3143 | goto out_err; |
3c56819b EGM |
3144 | |
3145 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
3146 | ret = -EFAULT; | |
34cd4998 | 3147 | goto out_err; |
3c56819b EGM |
3148 | } |
3149 | ||
4f535968 LJ |
3150 | trace_event_read_lock(); |
3151 | ||
3c56819b EGM |
3152 | /* Fill as many pages as possible. */ |
3153 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
3154 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
3155 | if (!pages[i]) |
3156 | break; | |
3c56819b | 3157 | |
fa7c7f6e | 3158 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3159 | |
3160 | /* Copy the data into the page, so we can start over. */ | |
3161 | ret = trace_seq_to_buffer(&iter->seq, | |
3162 | page_address(pages[i]), | |
3163 | iter->seq.len); | |
3164 | if (ret < 0) { | |
3165 | __free_page(pages[i]); | |
3166 | break; | |
3167 | } | |
3168 | partial[i].offset = 0; | |
3169 | partial[i].len = iter->seq.len; | |
3170 | ||
f9520750 | 3171 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3172 | } |
3173 | ||
4f535968 | 3174 | trace_event_read_unlock(); |
d7350c3f | 3175 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3176 | |
3177 | spd.nr_pages = i; | |
3178 | ||
3179 | return splice_to_pipe(pipe, &spd); | |
3180 | ||
34cd4998 | 3181 | out_err: |
d7350c3f | 3182 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3183 | |
3184 | return ret; | |
3185 | } | |
3186 | ||
a98a3c3f SR |
3187 | static ssize_t |
3188 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3189 | size_t cnt, loff_t *ppos) | |
3190 | { | |
3191 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3192 | char buf[96]; |
a98a3c3f SR |
3193 | int r; |
3194 | ||
db526ca3 SR |
3195 | mutex_lock(&trace_types_lock); |
3196 | if (!ring_buffer_expanded) | |
3197 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3198 | tr->entries >> 10, | |
3199 | trace_buf_size >> 10); | |
3200 | else | |
3201 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3202 | mutex_unlock(&trace_types_lock); | |
3203 | ||
a98a3c3f SR |
3204 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3205 | } | |
3206 | ||
3207 | static ssize_t | |
3208 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3209 | size_t cnt, loff_t *ppos) | |
3210 | { | |
3211 | unsigned long val; | |
3212 | char buf[64]; | |
bf5e6519 | 3213 | int ret, cpu; |
a98a3c3f | 3214 | |
cffae437 SR |
3215 | if (cnt >= sizeof(buf)) |
3216 | return -EINVAL; | |
a98a3c3f SR |
3217 | |
3218 | if (copy_from_user(&buf, ubuf, cnt)) | |
3219 | return -EFAULT; | |
3220 | ||
3221 | buf[cnt] = 0; | |
3222 | ||
c6caeeb1 SR |
3223 | ret = strict_strtoul(buf, 10, &val); |
3224 | if (ret < 0) | |
3225 | return ret; | |
a98a3c3f SR |
3226 | |
3227 | /* must have at least 1 entry */ | |
3228 | if (!val) | |
3229 | return -EINVAL; | |
3230 | ||
3231 | mutex_lock(&trace_types_lock); | |
3232 | ||
c76f0694 | 3233 | tracing_stop(); |
a98a3c3f | 3234 | |
bf5e6519 SR |
3235 | /* disable all cpu buffers */ |
3236 | for_each_tracing_cpu(cpu) { | |
3237 | if (global_trace.data[cpu]) | |
3238 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3239 | if (max_tr.data[cpu]) | |
3240 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3241 | } | |
3242 | ||
1696b2b0 SR |
3243 | /* value is in KB */ |
3244 | val <<= 10; | |
3245 | ||
3928a8a2 | 3246 | if (val != global_trace.entries) { |
73c5162a | 3247 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3248 | if (ret < 0) { |
3249 | cnt = ret; | |
3eefae99 SR |
3250 | goto out; |
3251 | } | |
a98a3c3f SR |
3252 | } |
3253 | ||
3254 | filp->f_pos += cnt; | |
3255 | ||
19384c03 SR |
3256 | /* If check pages failed, return ENOMEM */ |
3257 | if (tracing_disabled) | |
3258 | cnt = -ENOMEM; | |
a98a3c3f | 3259 | out: |
bf5e6519 SR |
3260 | for_each_tracing_cpu(cpu) { |
3261 | if (global_trace.data[cpu]) | |
3262 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3263 | if (max_tr.data[cpu]) | |
3264 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3265 | } | |
3266 | ||
c76f0694 | 3267 | tracing_start(); |
a98a3c3f SR |
3268 | max_tr.entries = global_trace.entries; |
3269 | mutex_unlock(&trace_types_lock); | |
3270 | ||
3271 | return cnt; | |
3272 | } | |
3273 | ||
5bf9a1ee PP |
3274 | static int mark_printk(const char *fmt, ...) |
3275 | { | |
3276 | int ret; | |
3277 | va_list args; | |
3278 | va_start(args, fmt); | |
40ce74f1 | 3279 | ret = trace_vprintk(0, fmt, args); |
5bf9a1ee PP |
3280 | va_end(args); |
3281 | return ret; | |
3282 | } | |
3283 | ||
3284 | static ssize_t | |
3285 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3286 | size_t cnt, loff_t *fpos) | |
3287 | { | |
3288 | char *buf; | |
3289 | char *end; | |
5bf9a1ee | 3290 | |
c76f0694 | 3291 | if (tracing_disabled) |
5bf9a1ee PP |
3292 | return -EINVAL; |
3293 | ||
3294 | if (cnt > TRACE_BUF_SIZE) | |
3295 | cnt = TRACE_BUF_SIZE; | |
3296 | ||
3297 | buf = kmalloc(cnt + 1, GFP_KERNEL); | |
3298 | if (buf == NULL) | |
3299 | return -ENOMEM; | |
3300 | ||
3301 | if (copy_from_user(buf, ubuf, cnt)) { | |
3302 | kfree(buf); | |
3303 | return -EFAULT; | |
3304 | } | |
3305 | ||
3306 | /* Cut from the first nil or newline. */ | |
3307 | buf[cnt] = '\0'; | |
3308 | end = strchr(buf, '\n'); | |
3309 | if (end) | |
3310 | *end = '\0'; | |
3311 | ||
3312 | cnt = mark_printk("%s\n", buf); | |
3313 | kfree(buf); | |
3314 | *fpos += cnt; | |
3315 | ||
3316 | return cnt; | |
3317 | } | |
3318 | ||
5e2336a0 | 3319 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3320 | .open = tracing_open_generic, |
3321 | .read = tracing_max_lat_read, | |
3322 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
3323 | }; |
3324 | ||
5e2336a0 | 3325 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3326 | .open = tracing_open_generic, |
3327 | .read = tracing_ctrl_read, | |
3328 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
3329 | }; |
3330 | ||
5e2336a0 | 3331 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3332 | .open = tracing_open_generic, |
3333 | .read = tracing_set_trace_read, | |
3334 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
3335 | }; |
3336 | ||
5e2336a0 | 3337 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3338 | .open = tracing_open_pipe, |
2a2cc8f7 | 3339 | .poll = tracing_poll_pipe, |
4bf39a94 | 3340 | .read = tracing_read_pipe, |
3c56819b | 3341 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3342 | .release = tracing_release_pipe, |
b3806b43 SR |
3343 | }; |
3344 | ||
5e2336a0 | 3345 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3346 | .open = tracing_open_generic, |
3347 | .read = tracing_entries_read, | |
3348 | .write = tracing_entries_write, | |
3349 | }; | |
3350 | ||
5e2336a0 | 3351 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3352 | .open = tracing_open_generic, |
5bf9a1ee PP |
3353 | .write = tracing_mark_write, |
3354 | }; | |
3355 | ||
2cadf913 SR |
3356 | struct ftrace_buffer_info { |
3357 | struct trace_array *tr; | |
3358 | void *spare; | |
3359 | int cpu; | |
3360 | unsigned int read; | |
3361 | }; | |
3362 | ||
3363 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3364 | { | |
3365 | int cpu = (int)(long)inode->i_private; | |
3366 | struct ftrace_buffer_info *info; | |
3367 | ||
3368 | if (tracing_disabled) | |
3369 | return -ENODEV; | |
3370 | ||
3371 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3372 | if (!info) | |
3373 | return -ENOMEM; | |
3374 | ||
3375 | info->tr = &global_trace; | |
3376 | info->cpu = cpu; | |
ddd538f3 | 3377 | info->spare = NULL; |
2cadf913 SR |
3378 | /* Force reading ring buffer for first read */ |
3379 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3380 | |
3381 | filp->private_data = info; | |
3382 | ||
d1e7e02f | 3383 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3384 | } |
3385 | ||
3386 | static ssize_t | |
3387 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3388 | size_t count, loff_t *ppos) | |
3389 | { | |
3390 | struct ftrace_buffer_info *info = filp->private_data; | |
3391 | unsigned int pos; | |
3392 | ssize_t ret; | |
3393 | size_t size; | |
3394 | ||
2dc5d12b SR |
3395 | if (!count) |
3396 | return 0; | |
3397 | ||
ddd538f3 LJ |
3398 | if (!info->spare) |
3399 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3400 | if (!info->spare) | |
3401 | return -ENOMEM; | |
3402 | ||
2cadf913 SR |
3403 | /* Do we have previous read data to read? */ |
3404 | if (info->read < PAGE_SIZE) | |
3405 | goto read; | |
3406 | ||
3407 | info->read = 0; | |
3408 | ||
3409 | ret = ring_buffer_read_page(info->tr->buffer, | |
3410 | &info->spare, | |
3411 | count, | |
3412 | info->cpu, 0); | |
3413 | if (ret < 0) | |
3414 | return 0; | |
3415 | ||
3416 | pos = ring_buffer_page_len(info->spare); | |
3417 | ||
3418 | if (pos < PAGE_SIZE) | |
3419 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3420 | ||
3421 | read: | |
3422 | size = PAGE_SIZE - info->read; | |
3423 | if (size > count) | |
3424 | size = count; | |
3425 | ||
3426 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3427 | if (ret == size) |
2cadf913 | 3428 | return -EFAULT; |
2dc5d12b SR |
3429 | size -= ret; |
3430 | ||
2cadf913 SR |
3431 | *ppos += size; |
3432 | info->read += size; | |
3433 | ||
3434 | return size; | |
3435 | } | |
3436 | ||
3437 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3438 | { | |
3439 | struct ftrace_buffer_info *info = file->private_data; | |
3440 | ||
ddd538f3 LJ |
3441 | if (info->spare) |
3442 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3443 | kfree(info); |
3444 | ||
3445 | return 0; | |
3446 | } | |
3447 | ||
3448 | struct buffer_ref { | |
3449 | struct ring_buffer *buffer; | |
3450 | void *page; | |
3451 | int ref; | |
3452 | }; | |
3453 | ||
3454 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3455 | struct pipe_buffer *buf) | |
3456 | { | |
3457 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3458 | ||
3459 | if (--ref->ref) | |
3460 | return; | |
3461 | ||
3462 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3463 | kfree(ref); | |
3464 | buf->private = 0; | |
3465 | } | |
3466 | ||
3467 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3468 | struct pipe_buffer *buf) | |
3469 | { | |
3470 | return 1; | |
3471 | } | |
3472 | ||
3473 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3474 | struct pipe_buffer *buf) | |
3475 | { | |
3476 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3477 | ||
3478 | ref->ref++; | |
3479 | } | |
3480 | ||
3481 | /* Pipe buffer operations for a buffer. */ | |
3482 | static struct pipe_buf_operations buffer_pipe_buf_ops = { | |
3483 | .can_merge = 0, | |
3484 | .map = generic_pipe_buf_map, | |
3485 | .unmap = generic_pipe_buf_unmap, | |
3486 | .confirm = generic_pipe_buf_confirm, | |
3487 | .release = buffer_pipe_buf_release, | |
3488 | .steal = buffer_pipe_buf_steal, | |
3489 | .get = buffer_pipe_buf_get, | |
3490 | }; | |
3491 | ||
3492 | /* | |
3493 | * Callback from splice_to_pipe(), if we need to release some pages | |
3494 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3495 | */ | |
3496 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3497 | { | |
3498 | struct buffer_ref *ref = | |
3499 | (struct buffer_ref *)spd->partial[i].private; | |
3500 | ||
3501 | if (--ref->ref) | |
3502 | return; | |
3503 | ||
3504 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3505 | kfree(ref); | |
3506 | spd->partial[i].private = 0; | |
3507 | } | |
3508 | ||
3509 | static ssize_t | |
3510 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3511 | struct pipe_inode_info *pipe, size_t len, | |
3512 | unsigned int flags) | |
3513 | { | |
3514 | struct ftrace_buffer_info *info = file->private_data; | |
3515 | struct partial_page partial[PIPE_BUFFERS]; | |
3516 | struct page *pages[PIPE_BUFFERS]; | |
3517 | struct splice_pipe_desc spd = { | |
3518 | .pages = pages, | |
3519 | .partial = partial, | |
3520 | .flags = flags, | |
3521 | .ops = &buffer_pipe_buf_ops, | |
3522 | .spd_release = buffer_spd_release, | |
3523 | }; | |
3524 | struct buffer_ref *ref; | |
93459c6c | 3525 | int entries, size, i; |
2cadf913 SR |
3526 | size_t ret; |
3527 | ||
93cfb3c9 LJ |
3528 | if (*ppos & (PAGE_SIZE - 1)) { |
3529 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
3530 | return -EINVAL; | |
3531 | } | |
3532 | ||
3533 | if (len & (PAGE_SIZE - 1)) { | |
3534 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
3535 | if (len < PAGE_SIZE) | |
3536 | return -EINVAL; | |
3537 | len &= PAGE_MASK; | |
3538 | } | |
3539 | ||
93459c6c SR |
3540 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
3541 | ||
3542 | for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) { | |
2cadf913 SR |
3543 | struct page *page; |
3544 | int r; | |
3545 | ||
3546 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3547 | if (!ref) | |
3548 | break; | |
3549 | ||
7267fa68 | 3550 | ref->ref = 1; |
2cadf913 SR |
3551 | ref->buffer = info->tr->buffer; |
3552 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3553 | if (!ref->page) { | |
3554 | kfree(ref); | |
3555 | break; | |
3556 | } | |
3557 | ||
3558 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 3559 | len, info->cpu, 1); |
2cadf913 SR |
3560 | if (r < 0) { |
3561 | ring_buffer_free_read_page(ref->buffer, | |
3562 | ref->page); | |
3563 | kfree(ref); | |
3564 | break; | |
3565 | } | |
3566 | ||
3567 | /* | |
3568 | * zero out any left over data, this is going to | |
3569 | * user land. | |
3570 | */ | |
3571 | size = ring_buffer_page_len(ref->page); | |
3572 | if (size < PAGE_SIZE) | |
3573 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3574 | ||
3575 | page = virt_to_page(ref->page); | |
3576 | ||
3577 | spd.pages[i] = page; | |
3578 | spd.partial[i].len = PAGE_SIZE; | |
3579 | spd.partial[i].offset = 0; | |
3580 | spd.partial[i].private = (unsigned long)ref; | |
3581 | spd.nr_pages++; | |
93cfb3c9 | 3582 | *ppos += PAGE_SIZE; |
93459c6c SR |
3583 | |
3584 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
3585 | } |
3586 | ||
3587 | spd.nr_pages = i; | |
3588 | ||
3589 | /* did we read anything? */ | |
3590 | if (!spd.nr_pages) { | |
3591 | if (flags & SPLICE_F_NONBLOCK) | |
3592 | ret = -EAGAIN; | |
3593 | else | |
3594 | ret = 0; | |
3595 | /* TODO: block */ | |
3596 | return ret; | |
3597 | } | |
3598 | ||
3599 | ret = splice_to_pipe(pipe, &spd); | |
3600 | ||
3601 | return ret; | |
3602 | } | |
3603 | ||
3604 | static const struct file_operations tracing_buffers_fops = { | |
3605 | .open = tracing_buffers_open, | |
3606 | .read = tracing_buffers_read, | |
3607 | .release = tracing_buffers_release, | |
3608 | .splice_read = tracing_buffers_splice_read, | |
3609 | .llseek = no_llseek, | |
3610 | }; | |
3611 | ||
c8d77183 SR |
3612 | static ssize_t |
3613 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
3614 | size_t count, loff_t *ppos) | |
3615 | { | |
3616 | unsigned long cpu = (unsigned long)filp->private_data; | |
3617 | struct trace_array *tr = &global_trace; | |
3618 | struct trace_seq *s; | |
3619 | unsigned long cnt; | |
3620 | ||
e4f2d10f | 3621 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 SR |
3622 | if (!s) |
3623 | return ENOMEM; | |
3624 | ||
3625 | trace_seq_init(s); | |
3626 | ||
3627 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
3628 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
3629 | ||
3630 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
3631 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
3632 | ||
3633 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
3634 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
3635 | ||
3636 | cnt = ring_buffer_nmi_dropped_cpu(tr->buffer, cpu); | |
3637 | trace_seq_printf(s, "nmi dropped: %ld\n", cnt); | |
3638 | ||
3639 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); | |
3640 | ||
3641 | kfree(s); | |
3642 | ||
3643 | return count; | |
3644 | } | |
3645 | ||
3646 | static const struct file_operations tracing_stats_fops = { | |
3647 | .open = tracing_open_generic, | |
3648 | .read = tracing_stats_read, | |
3649 | }; | |
3650 | ||
bc0c38d1 SR |
3651 | #ifdef CONFIG_DYNAMIC_FTRACE |
3652 | ||
b807c3d0 SR |
3653 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3654 | { | |
3655 | return 0; | |
3656 | } | |
3657 | ||
bc0c38d1 | 3658 | static ssize_t |
b807c3d0 | 3659 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3660 | size_t cnt, loff_t *ppos) |
3661 | { | |
a26a2a27 SR |
3662 | static char ftrace_dyn_info_buffer[1024]; |
3663 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3664 | unsigned long *p = filp->private_data; |
b807c3d0 | 3665 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3666 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3667 | int r; |
3668 | ||
b807c3d0 SR |
3669 | mutex_lock(&dyn_info_mutex); |
3670 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3671 | |
a26a2a27 | 3672 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3673 | buf[r++] = '\n'; |
3674 | ||
3675 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3676 | ||
3677 | mutex_unlock(&dyn_info_mutex); | |
3678 | ||
3679 | return r; | |
bc0c38d1 SR |
3680 | } |
3681 | ||
5e2336a0 | 3682 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3683 | .open = tracing_open_generic, |
b807c3d0 | 3684 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3685 | }; |
3686 | #endif | |
3687 | ||
3688 | static struct dentry *d_tracer; | |
3689 | ||
3690 | struct dentry *tracing_init_dentry(void) | |
3691 | { | |
3692 | static int once; | |
3693 | ||
3694 | if (d_tracer) | |
3695 | return d_tracer; | |
3696 | ||
3e1f60b8 FW |
3697 | if (!debugfs_initialized()) |
3698 | return NULL; | |
3699 | ||
bc0c38d1 SR |
3700 | d_tracer = debugfs_create_dir("tracing", NULL); |
3701 | ||
3702 | if (!d_tracer && !once) { | |
3703 | once = 1; | |
3704 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3705 | return NULL; | |
3706 | } | |
3707 | ||
3708 | return d_tracer; | |
3709 | } | |
3710 | ||
b04cc6b1 FW |
3711 | static struct dentry *d_percpu; |
3712 | ||
3713 | struct dentry *tracing_dentry_percpu(void) | |
3714 | { | |
3715 | static int once; | |
3716 | struct dentry *d_tracer; | |
3717 | ||
3718 | if (d_percpu) | |
3719 | return d_percpu; | |
3720 | ||
3721 | d_tracer = tracing_init_dentry(); | |
3722 | ||
3723 | if (!d_tracer) | |
3724 | return NULL; | |
3725 | ||
3726 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
3727 | ||
3728 | if (!d_percpu && !once) { | |
3729 | once = 1; | |
3730 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
3731 | return NULL; | |
3732 | } | |
3733 | ||
3734 | return d_percpu; | |
3735 | } | |
3736 | ||
3737 | static void tracing_init_debugfs_percpu(long cpu) | |
3738 | { | |
3739 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 3740 | struct dentry *d_cpu; |
8656e7a2 FW |
3741 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ |
3742 | char cpu_dir[7]; | |
b04cc6b1 FW |
3743 | |
3744 | if (cpu > 999 || cpu < 0) | |
3745 | return; | |
3746 | ||
8656e7a2 FW |
3747 | sprintf(cpu_dir, "cpu%ld", cpu); |
3748 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
3749 | if (!d_cpu) { | |
3750 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
3751 | return; | |
3752 | } | |
b04cc6b1 | 3753 | |
8656e7a2 | 3754 | /* per cpu trace_pipe */ |
5452af66 FW |
3755 | trace_create_file("trace_pipe", 0444, d_cpu, |
3756 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
3757 | |
3758 | /* per cpu trace */ | |
5452af66 FW |
3759 | trace_create_file("trace", 0644, d_cpu, |
3760 | (void *) cpu, &tracing_fops); | |
7f96f93f | 3761 | |
5452af66 FW |
3762 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
3763 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 3764 | |
c8d77183 SR |
3765 | trace_create_file("stats", 0444, d_cpu, |
3766 | (void *) cpu, &tracing_stats_fops); | |
b04cc6b1 FW |
3767 | } |
3768 | ||
60a11774 SR |
3769 | #ifdef CONFIG_FTRACE_SELFTEST |
3770 | /* Let selftest have access to static functions in this file */ | |
3771 | #include "trace_selftest.c" | |
3772 | #endif | |
3773 | ||
577b785f SR |
3774 | struct trace_option_dentry { |
3775 | struct tracer_opt *opt; | |
3776 | struct tracer_flags *flags; | |
3777 | struct dentry *entry; | |
3778 | }; | |
3779 | ||
3780 | static ssize_t | |
3781 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3782 | loff_t *ppos) | |
3783 | { | |
3784 | struct trace_option_dentry *topt = filp->private_data; | |
3785 | char *buf; | |
3786 | ||
3787 | if (topt->flags->val & topt->opt->bit) | |
3788 | buf = "1\n"; | |
3789 | else | |
3790 | buf = "0\n"; | |
3791 | ||
3792 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3793 | } | |
3794 | ||
3795 | static ssize_t | |
3796 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3797 | loff_t *ppos) | |
3798 | { | |
3799 | struct trace_option_dentry *topt = filp->private_data; | |
3800 | unsigned long val; | |
3801 | char buf[64]; | |
3802 | int ret; | |
3803 | ||
3804 | if (cnt >= sizeof(buf)) | |
3805 | return -EINVAL; | |
3806 | ||
3807 | if (copy_from_user(&buf, ubuf, cnt)) | |
3808 | return -EFAULT; | |
3809 | ||
3810 | buf[cnt] = 0; | |
3811 | ||
3812 | ret = strict_strtoul(buf, 10, &val); | |
3813 | if (ret < 0) | |
3814 | return ret; | |
3815 | ||
3816 | ret = 0; | |
3817 | switch (val) { | |
3818 | case 0: | |
3819 | /* do nothing if already cleared */ | |
3820 | if (!(topt->flags->val & topt->opt->bit)) | |
3821 | break; | |
3822 | ||
3823 | mutex_lock(&trace_types_lock); | |
3824 | if (current_trace->set_flag) | |
3825 | ret = current_trace->set_flag(topt->flags->val, | |
3826 | topt->opt->bit, 0); | |
3827 | mutex_unlock(&trace_types_lock); | |
3828 | if (ret) | |
3829 | return ret; | |
3830 | topt->flags->val &= ~topt->opt->bit; | |
3831 | break; | |
3832 | case 1: | |
3833 | /* do nothing if already set */ | |
3834 | if (topt->flags->val & topt->opt->bit) | |
3835 | break; | |
3836 | ||
3837 | mutex_lock(&trace_types_lock); | |
3838 | if (current_trace->set_flag) | |
3839 | ret = current_trace->set_flag(topt->flags->val, | |
3840 | topt->opt->bit, 1); | |
3841 | mutex_unlock(&trace_types_lock); | |
3842 | if (ret) | |
3843 | return ret; | |
3844 | topt->flags->val |= topt->opt->bit; | |
3845 | break; | |
3846 | ||
3847 | default: | |
3848 | return -EINVAL; | |
3849 | } | |
3850 | ||
3851 | *ppos += cnt; | |
3852 | ||
3853 | return cnt; | |
3854 | } | |
3855 | ||
3856 | ||
3857 | static const struct file_operations trace_options_fops = { | |
3858 | .open = tracing_open_generic, | |
3859 | .read = trace_options_read, | |
3860 | .write = trace_options_write, | |
3861 | }; | |
3862 | ||
a8259075 SR |
3863 | static ssize_t |
3864 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3865 | loff_t *ppos) | |
3866 | { | |
3867 | long index = (long)filp->private_data; | |
3868 | char *buf; | |
3869 | ||
3870 | if (trace_flags & (1 << index)) | |
3871 | buf = "1\n"; | |
3872 | else | |
3873 | buf = "0\n"; | |
3874 | ||
3875 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3876 | } | |
3877 | ||
3878 | static ssize_t | |
3879 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3880 | loff_t *ppos) | |
3881 | { | |
3882 | long index = (long)filp->private_data; | |
3883 | char buf[64]; | |
3884 | unsigned long val; | |
3885 | int ret; | |
3886 | ||
3887 | if (cnt >= sizeof(buf)) | |
3888 | return -EINVAL; | |
3889 | ||
3890 | if (copy_from_user(&buf, ubuf, cnt)) | |
3891 | return -EFAULT; | |
3892 | ||
3893 | buf[cnt] = 0; | |
3894 | ||
3895 | ret = strict_strtoul(buf, 10, &val); | |
3896 | if (ret < 0) | |
3897 | return ret; | |
3898 | ||
3899 | switch (val) { | |
3900 | case 0: | |
3901 | trace_flags &= ~(1 << index); | |
3902 | break; | |
3903 | case 1: | |
3904 | trace_flags |= 1 << index; | |
3905 | break; | |
3906 | ||
3907 | default: | |
3908 | return -EINVAL; | |
3909 | } | |
3910 | ||
3911 | *ppos += cnt; | |
3912 | ||
3913 | return cnt; | |
3914 | } | |
3915 | ||
a8259075 SR |
3916 | static const struct file_operations trace_options_core_fops = { |
3917 | .open = tracing_open_generic, | |
3918 | .read = trace_options_core_read, | |
3919 | .write = trace_options_core_write, | |
3920 | }; | |
3921 | ||
5452af66 FW |
3922 | struct dentry *trace_create_file(const char *name, |
3923 | mode_t mode, | |
3924 | struct dentry *parent, | |
3925 | void *data, | |
3926 | const struct file_operations *fops) | |
3927 | { | |
3928 | struct dentry *ret; | |
3929 | ||
3930 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
3931 | if (!ret) | |
3932 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
3933 | ||
3934 | return ret; | |
3935 | } | |
3936 | ||
3937 | ||
a8259075 SR |
3938 | static struct dentry *trace_options_init_dentry(void) |
3939 | { | |
3940 | struct dentry *d_tracer; | |
3941 | static struct dentry *t_options; | |
3942 | ||
3943 | if (t_options) | |
3944 | return t_options; | |
3945 | ||
3946 | d_tracer = tracing_init_dentry(); | |
3947 | if (!d_tracer) | |
3948 | return NULL; | |
3949 | ||
3950 | t_options = debugfs_create_dir("options", d_tracer); | |
3951 | if (!t_options) { | |
3952 | pr_warning("Could not create debugfs directory 'options'\n"); | |
3953 | return NULL; | |
3954 | } | |
3955 | ||
3956 | return t_options; | |
3957 | } | |
3958 | ||
577b785f SR |
3959 | static void |
3960 | create_trace_option_file(struct trace_option_dentry *topt, | |
3961 | struct tracer_flags *flags, | |
3962 | struct tracer_opt *opt) | |
3963 | { | |
3964 | struct dentry *t_options; | |
577b785f SR |
3965 | |
3966 | t_options = trace_options_init_dentry(); | |
3967 | if (!t_options) | |
3968 | return; | |
3969 | ||
3970 | topt->flags = flags; | |
3971 | topt->opt = opt; | |
3972 | ||
5452af66 | 3973 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
3974 | &trace_options_fops); |
3975 | ||
577b785f SR |
3976 | } |
3977 | ||
3978 | static struct trace_option_dentry * | |
3979 | create_trace_option_files(struct tracer *tracer) | |
3980 | { | |
3981 | struct trace_option_dentry *topts; | |
3982 | struct tracer_flags *flags; | |
3983 | struct tracer_opt *opts; | |
3984 | int cnt; | |
3985 | ||
3986 | if (!tracer) | |
3987 | return NULL; | |
3988 | ||
3989 | flags = tracer->flags; | |
3990 | ||
3991 | if (!flags || !flags->opts) | |
3992 | return NULL; | |
3993 | ||
3994 | opts = flags->opts; | |
3995 | ||
3996 | for (cnt = 0; opts[cnt].name; cnt++) | |
3997 | ; | |
3998 | ||
0cfe8245 | 3999 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
4000 | if (!topts) |
4001 | return NULL; | |
4002 | ||
4003 | for (cnt = 0; opts[cnt].name; cnt++) | |
4004 | create_trace_option_file(&topts[cnt], flags, | |
4005 | &opts[cnt]); | |
4006 | ||
4007 | return topts; | |
4008 | } | |
4009 | ||
4010 | static void | |
4011 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
4012 | { | |
4013 | int cnt; | |
4014 | ||
4015 | if (!topts) | |
4016 | return; | |
4017 | ||
4018 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
4019 | if (topts[cnt].entry) | |
4020 | debugfs_remove(topts[cnt].entry); | |
4021 | } | |
4022 | ||
4023 | kfree(topts); | |
4024 | } | |
4025 | ||
a8259075 SR |
4026 | static struct dentry * |
4027 | create_trace_option_core_file(const char *option, long index) | |
4028 | { | |
4029 | struct dentry *t_options; | |
a8259075 SR |
4030 | |
4031 | t_options = trace_options_init_dentry(); | |
4032 | if (!t_options) | |
4033 | return NULL; | |
4034 | ||
5452af66 | 4035 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 4036 | &trace_options_core_fops); |
a8259075 SR |
4037 | } |
4038 | ||
4039 | static __init void create_trace_options_dir(void) | |
4040 | { | |
4041 | struct dentry *t_options; | |
a8259075 SR |
4042 | int i; |
4043 | ||
4044 | t_options = trace_options_init_dentry(); | |
4045 | if (!t_options) | |
4046 | return; | |
4047 | ||
5452af66 FW |
4048 | for (i = 0; trace_options[i]; i++) |
4049 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4050 | } |
4051 | ||
b5ad384e | 4052 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4053 | { |
4054 | struct dentry *d_tracer; | |
b04cc6b1 | 4055 | int cpu; |
bc0c38d1 SR |
4056 | |
4057 | d_tracer = tracing_init_dentry(); | |
4058 | ||
5452af66 FW |
4059 | trace_create_file("tracing_enabled", 0644, d_tracer, |
4060 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 4061 | |
5452af66 FW |
4062 | trace_create_file("trace_options", 0644, d_tracer, |
4063 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4064 | |
5452af66 FW |
4065 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4066 | NULL, &tracing_cpumask_fops); | |
4067 | ||
4068 | trace_create_file("trace", 0644, d_tracer, | |
4069 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 4070 | |
5452af66 FW |
4071 | trace_create_file("available_tracers", 0444, d_tracer, |
4072 | &global_trace, &show_traces_fops); | |
4073 | ||
339ae5d3 | 4074 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4075 | &global_trace, &set_tracer_fops); |
4076 | ||
4077 | trace_create_file("tracing_max_latency", 0644, d_tracer, | |
4078 | &tracing_max_latency, &tracing_max_lat_fops); | |
4079 | ||
4080 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4081 | &tracing_thresh, &tracing_max_lat_fops); | |
a8259075 | 4082 | |
339ae5d3 | 4083 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4084 | NULL, &tracing_readme_fops); |
4085 | ||
4086 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4087 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4088 | |
4089 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
4090 | &global_trace, &tracing_entries_fops); | |
4091 | ||
4092 | trace_create_file("trace_marker", 0220, d_tracer, | |
4093 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4094 | |
69abe6a5 AP |
4095 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4096 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 4097 | |
bc0c38d1 | 4098 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4099 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4100 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4101 | #endif |
d618b3e6 IM |
4102 | #ifdef CONFIG_SYSPROF_TRACER |
4103 | init_tracer_sysprof_debugfs(d_tracer); | |
4104 | #endif | |
b04cc6b1 | 4105 | |
5452af66 FW |
4106 | create_trace_options_dir(); |
4107 | ||
b04cc6b1 FW |
4108 | for_each_tracing_cpu(cpu) |
4109 | tracing_init_debugfs_percpu(cpu); | |
4110 | ||
b5ad384e | 4111 | return 0; |
bc0c38d1 SR |
4112 | } |
4113 | ||
3f5a54e3 SR |
4114 | static int trace_panic_handler(struct notifier_block *this, |
4115 | unsigned long event, void *unused) | |
4116 | { | |
944ac425 SR |
4117 | if (ftrace_dump_on_oops) |
4118 | ftrace_dump(); | |
3f5a54e3 SR |
4119 | return NOTIFY_OK; |
4120 | } | |
4121 | ||
4122 | static struct notifier_block trace_panic_notifier = { | |
4123 | .notifier_call = trace_panic_handler, | |
4124 | .next = NULL, | |
4125 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4126 | }; | |
4127 | ||
4128 | static int trace_die_handler(struct notifier_block *self, | |
4129 | unsigned long val, | |
4130 | void *data) | |
4131 | { | |
4132 | switch (val) { | |
4133 | case DIE_OOPS: | |
944ac425 SR |
4134 | if (ftrace_dump_on_oops) |
4135 | ftrace_dump(); | |
3f5a54e3 SR |
4136 | break; |
4137 | default: | |
4138 | break; | |
4139 | } | |
4140 | return NOTIFY_OK; | |
4141 | } | |
4142 | ||
4143 | static struct notifier_block trace_die_notifier = { | |
4144 | .notifier_call = trace_die_handler, | |
4145 | .priority = 200 | |
4146 | }; | |
4147 | ||
4148 | /* | |
4149 | * printk is set to max of 1024, we really don't need it that big. | |
4150 | * Nothing should be printing 1000 characters anyway. | |
4151 | */ | |
4152 | #define TRACE_MAX_PRINT 1000 | |
4153 | ||
4154 | /* | |
4155 | * Define here KERN_TRACE so that we have one place to modify | |
4156 | * it if we decide to change what log level the ftrace dump | |
4157 | * should be at. | |
4158 | */ | |
428aee14 | 4159 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
4160 | |
4161 | static void | |
4162 | trace_printk_seq(struct trace_seq *s) | |
4163 | { | |
4164 | /* Probably should print a warning here. */ | |
4165 | if (s->len >= 1000) | |
4166 | s->len = 1000; | |
4167 | ||
4168 | /* should be zero ended, but we are paranoid. */ | |
4169 | s->buffer[s->len] = 0; | |
4170 | ||
4171 | printk(KERN_TRACE "%s", s->buffer); | |
4172 | ||
f9520750 | 4173 | trace_seq_init(s); |
3f5a54e3 SR |
4174 | } |
4175 | ||
cf586b61 | 4176 | static void __ftrace_dump(bool disable_tracing) |
3f5a54e3 | 4177 | { |
cd891ae0 SR |
4178 | static raw_spinlock_t ftrace_dump_lock = |
4179 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
3f5a54e3 SR |
4180 | /* use static because iter can be a bit big for the stack */ |
4181 | static struct trace_iterator iter; | |
cf586b61 | 4182 | unsigned int old_userobj; |
3f5a54e3 | 4183 | static int dump_ran; |
d769041f SR |
4184 | unsigned long flags; |
4185 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4186 | |
4187 | /* only one dump */ | |
cd891ae0 SR |
4188 | local_irq_save(flags); |
4189 | __raw_spin_lock(&ftrace_dump_lock); | |
3f5a54e3 SR |
4190 | if (dump_ran) |
4191 | goto out; | |
4192 | ||
4193 | dump_ran = 1; | |
4194 | ||
0ee6b6cf | 4195 | tracing_off(); |
cf586b61 FW |
4196 | |
4197 | if (disable_tracing) | |
4198 | ftrace_kill(); | |
3f5a54e3 | 4199 | |
d769041f SR |
4200 | for_each_tracing_cpu(cpu) { |
4201 | atomic_inc(&global_trace.data[cpu]->disabled); | |
4202 | } | |
4203 | ||
cf586b61 FW |
4204 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4205 | ||
b54d3de9 TE |
4206 | /* don't look at user memory in panic mode */ |
4207 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4208 | ||
3f5a54e3 SR |
4209 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
4210 | ||
e543ad76 | 4211 | /* Simulate the iterator */ |
3f5a54e3 SR |
4212 | iter.tr = &global_trace; |
4213 | iter.trace = current_trace; | |
e543ad76 | 4214 | iter.cpu_file = TRACE_PIPE_ALL_CPU; |
3f5a54e3 SR |
4215 | |
4216 | /* | |
4217 | * We need to stop all tracing on all CPUS to read the | |
4218 | * the next buffer. This is a bit expensive, but is | |
4219 | * not done often. We fill all what we can read, | |
4220 | * and then release the locks again. | |
4221 | */ | |
4222 | ||
3f5a54e3 SR |
4223 | while (!trace_empty(&iter)) { |
4224 | ||
4225 | if (!cnt) | |
4226 | printk(KERN_TRACE "---------------------------------\n"); | |
4227 | ||
4228 | cnt++; | |
4229 | ||
4230 | /* reset all but tr, trace, and overruns */ | |
4231 | memset(&iter.seq, 0, | |
4232 | sizeof(struct trace_iterator) - | |
4233 | offsetof(struct trace_iterator, seq)); | |
4234 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4235 | iter.pos = -1; | |
4236 | ||
4237 | if (find_next_entry_inc(&iter) != NULL) { | |
74e7ff8c LJ |
4238 | int ret; |
4239 | ||
4240 | ret = print_trace_line(&iter); | |
4241 | if (ret != TRACE_TYPE_NO_CONSUME) | |
4242 | trace_consume(&iter); | |
3f5a54e3 SR |
4243 | } |
4244 | ||
4245 | trace_printk_seq(&iter.seq); | |
4246 | } | |
4247 | ||
4248 | if (!cnt) | |
4249 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4250 | else | |
4251 | printk(KERN_TRACE "---------------------------------\n"); | |
4252 | ||
cf586b61 FW |
4253 | /* Re-enable tracing if requested */ |
4254 | if (!disable_tracing) { | |
4255 | trace_flags |= old_userobj; | |
4256 | ||
4257 | for_each_tracing_cpu(cpu) { | |
4258 | atomic_dec(&global_trace.data[cpu]->disabled); | |
4259 | } | |
4260 | tracing_on(); | |
4261 | } | |
4262 | ||
3f5a54e3 | 4263 | out: |
cd891ae0 SR |
4264 | __raw_spin_unlock(&ftrace_dump_lock); |
4265 | local_irq_restore(flags); | |
3f5a54e3 SR |
4266 | } |
4267 | ||
cf586b61 FW |
4268 | /* By default: disable tracing after the dump */ |
4269 | void ftrace_dump(void) | |
4270 | { | |
4271 | __ftrace_dump(true); | |
4272 | } | |
4273 | ||
3928a8a2 | 4274 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4275 | { |
4c11d7ae | 4276 | struct trace_array_cpu *data; |
73c5162a | 4277 | int ring_buf_size; |
4c11d7ae | 4278 | int i; |
9e01c1b7 | 4279 | int ret = -ENOMEM; |
4c11d7ae | 4280 | |
9e01c1b7 RR |
4281 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4282 | goto out; | |
4283 | ||
4284 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4285 | goto out_free_buffer_mask; | |
4c11d7ae | 4286 | |
b04cc6b1 FW |
4287 | if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) |
4288 | goto out_free_tracing_cpumask; | |
4289 | ||
73c5162a SR |
4290 | /* To save memory, keep the ring buffer size to its minimum */ |
4291 | if (ring_buffer_expanded) | |
4292 | ring_buf_size = trace_buf_size; | |
4293 | else | |
4294 | ring_buf_size = 1; | |
4295 | ||
9e01c1b7 RR |
4296 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4297 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
b04cc6b1 | 4298 | cpumask_clear(tracing_reader_cpumask); |
9e01c1b7 RR |
4299 | |
4300 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
73c5162a | 4301 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4302 | TRACE_BUFFER_FLAGS); |
4303 | if (!global_trace.buffer) { | |
4304 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4305 | WARN_ON(1); | |
9e01c1b7 | 4306 | goto out_free_cpumask; |
4c11d7ae | 4307 | } |
3928a8a2 | 4308 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4309 | |
9e01c1b7 | 4310 | |
4c11d7ae | 4311 | #ifdef CONFIG_TRACER_MAX_TRACE |
73c5162a | 4312 | max_tr.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4313 | TRACE_BUFFER_FLAGS); |
4314 | if (!max_tr.buffer) { | |
4315 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4316 | WARN_ON(1); | |
4317 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4318 | goto out_free_cpumask; |
4c11d7ae | 4319 | } |
3928a8a2 SR |
4320 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
4321 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 4322 | #endif |
ab46428c | 4323 | |
4c11d7ae | 4324 | /* Allocate the first page for all buffers */ |
ab46428c | 4325 | for_each_tracing_cpu(i) { |
4c11d7ae | 4326 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 | 4327 | max_tr.data[i] = &per_cpu(max_data, i); |
4c11d7ae | 4328 | } |
bc0c38d1 | 4329 | |
bc0c38d1 SR |
4330 | trace_init_cmdlines(); |
4331 | ||
43a15386 | 4332 | register_tracer(&nop_trace); |
79fb0768 | 4333 | current_trace = &nop_trace; |
b5ad384e FW |
4334 | #ifdef CONFIG_BOOT_TRACER |
4335 | register_tracer(&boot_tracer); | |
b5ad384e | 4336 | #endif |
60a11774 SR |
4337 | /* All seems OK, enable tracing */ |
4338 | tracing_disabled = 0; | |
3928a8a2 | 4339 | |
3f5a54e3 SR |
4340 | atomic_notifier_chain_register(&panic_notifier_list, |
4341 | &trace_panic_notifier); | |
4342 | ||
4343 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4344 | |
4345 | return 0; | |
3f5a54e3 | 4346 | |
9e01c1b7 | 4347 | out_free_cpumask: |
b04cc6b1 FW |
4348 | free_cpumask_var(tracing_reader_cpumask); |
4349 | out_free_tracing_cpumask: | |
9e01c1b7 RR |
4350 | free_cpumask_var(tracing_cpumask); |
4351 | out_free_buffer_mask: | |
4352 | free_cpumask_var(tracing_buffer_mask); | |
4353 | out: | |
4354 | return ret; | |
bc0c38d1 | 4355 | } |
b2821ae6 SR |
4356 | |
4357 | __init static int clear_boot_tracer(void) | |
4358 | { | |
4359 | /* | |
4360 | * The default tracer at boot buffer is an init section. | |
4361 | * This function is called in lateinit. If we did not | |
4362 | * find the boot tracer, then clear it out, to prevent | |
4363 | * later registration from accessing the buffer that is | |
4364 | * about to be freed. | |
4365 | */ | |
4366 | if (!default_bootup_tracer) | |
4367 | return 0; | |
4368 | ||
4369 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4370 | default_bootup_tracer); | |
4371 | default_bootup_tracer = NULL; | |
4372 | ||
4373 | return 0; | |
4374 | } | |
4375 | ||
b5ad384e FW |
4376 | early_initcall(tracer_alloc_buffers); |
4377 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4378 | late_initcall(clear_boot_tracer); |