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Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
bc0c38d1 | 15 | #include <linux/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
4c11d7ae | 23 | #include <linux/pagemap.h> |
bc0c38d1 SR |
24 | #include <linux/hardirq.h> |
25 | #include <linux/linkage.h> | |
26 | #include <linux/uaccess.h> | |
2cadf913 | 27 | #include <linux/kprobes.h> |
bc0c38d1 SR |
28 | #include <linux/ftrace.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/percpu.h> | |
2cadf913 | 31 | #include <linux/splice.h> |
3f5a54e3 | 32 | #include <linux/kdebug.h> |
bc0c38d1 SR |
33 | #include <linux/ctype.h> |
34 | #include <linux/init.h> | |
2a2cc8f7 | 35 | #include <linux/poll.h> |
bc0c38d1 SR |
36 | #include <linux/gfp.h> |
37 | #include <linux/fs.h> | |
86387f7e | 38 | |
bc0c38d1 | 39 | #include "trace.h" |
f0868d1e | 40 | #include "trace_output.h" |
bc0c38d1 | 41 | |
3928a8a2 SR |
42 | #define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE) |
43 | ||
745b1626 | 44 | unsigned long __read_mostly tracing_max_latency; |
bc0c38d1 SR |
45 | unsigned long __read_mostly tracing_thresh; |
46 | ||
73c5162a SR |
47 | /* |
48 | * On boot up, the ring buffer is set to the minimum size, so that | |
49 | * we do not waste memory on systems that are not using tracing. | |
50 | */ | |
51 | static int ring_buffer_expanded; | |
52 | ||
8e1b82e0 FW |
53 | /* |
54 | * We need to change this state when a selftest is running. | |
ff32504f FW |
55 | * A selftest will lurk into the ring-buffer to count the |
56 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 57 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
58 | * at the same time, giving false positive or negative results. |
59 | */ | |
8e1b82e0 | 60 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 61 | |
b2821ae6 SR |
62 | /* |
63 | * If a tracer is running, we do not want to run SELFTEST. | |
64 | */ | |
65 | static bool __read_mostly tracing_selftest_disabled; | |
66 | ||
adf9f195 FW |
67 | /* For tracers that don't implement custom flags */ |
68 | static struct tracer_opt dummy_tracer_opt[] = { | |
69 | { } | |
70 | }; | |
71 | ||
72 | static struct tracer_flags dummy_tracer_flags = { | |
73 | .val = 0, | |
74 | .opts = dummy_tracer_opt | |
75 | }; | |
76 | ||
77 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
78 | { | |
79 | return 0; | |
80 | } | |
0f048701 SR |
81 | |
82 | /* | |
83 | * Kill all tracing for good (never come back). | |
84 | * It is initialized to 1 but will turn to zero if the initialization | |
85 | * of the tracer is successful. But that is the only place that sets | |
86 | * this back to zero. | |
87 | */ | |
4fd27358 | 88 | static int tracing_disabled = 1; |
0f048701 | 89 | |
d769041f SR |
90 | static DEFINE_PER_CPU(local_t, ftrace_cpu_disabled); |
91 | ||
92 | static inline void ftrace_disable_cpu(void) | |
93 | { | |
94 | preempt_disable(); | |
95 | local_inc(&__get_cpu_var(ftrace_cpu_disabled)); | |
96 | } | |
97 | ||
98 | static inline void ftrace_enable_cpu(void) | |
99 | { | |
100 | local_dec(&__get_cpu_var(ftrace_cpu_disabled)); | |
101 | preempt_enable(); | |
102 | } | |
103 | ||
9e01c1b7 | 104 | static cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 105 | |
b04cc6b1 FW |
106 | /* Define which cpu buffers are currently read in trace_pipe */ |
107 | static cpumask_var_t tracing_reader_cpumask; | |
108 | ||
ab46428c | 109 | #define for_each_tracing_cpu(cpu) \ |
9e01c1b7 | 110 | for_each_cpu(cpu, tracing_buffer_mask) |
ab46428c | 111 | |
944ac425 SR |
112 | /* |
113 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
114 | * | |
115 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
116 | * is set, then ftrace_dump is called. This will output the contents | |
117 | * of the ftrace buffers to the console. This is very useful for | |
118 | * capturing traces that lead to crashes and outputing it to a | |
119 | * serial console. | |
120 | * | |
121 | * It is default off, but you can enable it with either specifying | |
122 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
123 | * /proc/sys/kernel/ftrace_dump_on_oops to true. | |
124 | */ | |
125 | int ftrace_dump_on_oops; | |
126 | ||
b2821ae6 SR |
127 | static int tracing_set_tracer(const char *buf); |
128 | ||
129 | #define BOOTUP_TRACER_SIZE 100 | |
130 | static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata; | |
131 | static char *default_bootup_tracer; | |
d9e54076 PZ |
132 | |
133 | static int __init set_ftrace(char *str) | |
134 | { | |
b2821ae6 SR |
135 | strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); |
136 | default_bootup_tracer = bootup_tracer_buf; | |
73c5162a SR |
137 | /* We are using ftrace early, expand it */ |
138 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
139 | return 1; |
140 | } | |
b2821ae6 | 141 | __setup("ftrace=", set_ftrace); |
d9e54076 | 142 | |
944ac425 SR |
143 | static int __init set_ftrace_dump_on_oops(char *str) |
144 | { | |
145 | ftrace_dump_on_oops = 1; | |
146 | return 1; | |
147 | } | |
148 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 149 | |
72829bc3 | 150 | long |
bc0c38d1 SR |
151 | ns2usecs(cycle_t nsec) |
152 | { | |
153 | nsec += 500; | |
154 | do_div(nsec, 1000); | |
155 | return nsec; | |
156 | } | |
157 | ||
e309b41d | 158 | cycle_t ftrace_now(int cpu) |
750ed1a4 | 159 | { |
3928a8a2 SR |
160 | u64 ts = ring_buffer_time_stamp(cpu); |
161 | ring_buffer_normalize_time_stamp(cpu, &ts); | |
162 | return ts; | |
750ed1a4 IM |
163 | } |
164 | ||
4fcdae83 SR |
165 | /* |
166 | * The global_trace is the descriptor that holds the tracing | |
167 | * buffers for the live tracing. For each CPU, it contains | |
168 | * a link list of pages that will store trace entries. The | |
169 | * page descriptor of the pages in the memory is used to hold | |
170 | * the link list by linking the lru item in the page descriptor | |
171 | * to each of the pages in the buffer per CPU. | |
172 | * | |
173 | * For each active CPU there is a data field that holds the | |
174 | * pages for the buffer for that CPU. Each CPU has the same number | |
175 | * of pages allocated for its buffer. | |
176 | */ | |
bc0c38d1 SR |
177 | static struct trace_array global_trace; |
178 | ||
179 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
180 | ||
4fcdae83 SR |
181 | /* |
182 | * The max_tr is used to snapshot the global_trace when a maximum | |
183 | * latency is reached. Some tracers will use this to store a maximum | |
184 | * trace while it continues examining live traces. | |
185 | * | |
186 | * The buffers for the max_tr are set up the same as the global_trace. | |
187 | * When a snapshot is taken, the link list of the max_tr is swapped | |
188 | * with the link list of the global_trace and the buffers are reset for | |
189 | * the global_trace so the tracing can continue. | |
190 | */ | |
bc0c38d1 SR |
191 | static struct trace_array max_tr; |
192 | ||
193 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
194 | ||
4fcdae83 | 195 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 196 | static int tracer_enabled = 1; |
4fcdae83 | 197 | |
9036990d SR |
198 | /** |
199 | * tracing_is_enabled - return tracer_enabled status | |
200 | * | |
201 | * This function is used by other tracers to know the status | |
202 | * of the tracer_enabled flag. Tracers may use this function | |
203 | * to know if it should enable their features when starting | |
204 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
205 | */ | |
206 | int tracing_is_enabled(void) | |
207 | { | |
208 | return tracer_enabled; | |
209 | } | |
210 | ||
4fcdae83 | 211 | /* |
3928a8a2 SR |
212 | * trace_buf_size is the size in bytes that is allocated |
213 | * for a buffer. Note, the number of bytes is always rounded | |
214 | * to page size. | |
3f5a54e3 SR |
215 | * |
216 | * This number is purposely set to a low number of 16384. | |
217 | * If the dump on oops happens, it will be much appreciated | |
218 | * to not have to wait for all that output. Anyway this can be | |
219 | * boot time and run time configurable. | |
4fcdae83 | 220 | */ |
3928a8a2 | 221 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 222 | |
3928a8a2 | 223 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 224 | |
4fcdae83 | 225 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 226 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
227 | |
228 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 229 | static struct tracer *current_trace __read_mostly; |
4fcdae83 SR |
230 | |
231 | /* | |
232 | * max_tracer_type_len is used to simplify the allocating of | |
233 | * buffers to read userspace tracer names. We keep track of | |
234 | * the longest tracer name registered. | |
235 | */ | |
bc0c38d1 SR |
236 | static int max_tracer_type_len; |
237 | ||
4fcdae83 SR |
238 | /* |
239 | * trace_types_lock is used to protect the trace_types list. | |
240 | * This lock is also used to keep user access serialized. | |
241 | * Accesses from userspace will grab this lock while userspace | |
242 | * activities happen inside the kernel. | |
243 | */ | |
bc0c38d1 | 244 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
245 | |
246 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
247 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
248 | ||
ee6bce52 | 249 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 250 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
c4a8e8be | 251 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO; |
4e655519 | 252 | |
4fcdae83 SR |
253 | /** |
254 | * trace_wake_up - wake up tasks waiting for trace input | |
255 | * | |
256 | * Simply wakes up any task that is blocked on the trace_wait | |
257 | * queue. These is used with trace_poll for tasks polling the trace. | |
258 | */ | |
4e655519 IM |
259 | void trace_wake_up(void) |
260 | { | |
017730c1 IM |
261 | /* |
262 | * The runqueue_is_locked() can fail, but this is the best we | |
263 | * have for now: | |
264 | */ | |
265 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
266 | wake_up(&trace_wait); |
267 | } | |
bc0c38d1 | 268 | |
3928a8a2 | 269 | static int __init set_buf_size(char *str) |
bc0c38d1 | 270 | { |
3928a8a2 | 271 | unsigned long buf_size; |
c6caeeb1 SR |
272 | int ret; |
273 | ||
bc0c38d1 SR |
274 | if (!str) |
275 | return 0; | |
3928a8a2 | 276 | ret = strict_strtoul(str, 0, &buf_size); |
c6caeeb1 | 277 | /* nr_entries can not be zero */ |
3928a8a2 | 278 | if (ret < 0 || buf_size == 0) |
c6caeeb1 | 279 | return 0; |
3928a8a2 | 280 | trace_buf_size = buf_size; |
bc0c38d1 SR |
281 | return 1; |
282 | } | |
3928a8a2 | 283 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 284 | |
57f50be1 SR |
285 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
286 | { | |
287 | return nsecs / 1000; | |
288 | } | |
289 | ||
4fcdae83 | 290 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
291 | static const char *trace_options[] = { |
292 | "print-parent", | |
293 | "sym-offset", | |
294 | "sym-addr", | |
295 | "verbose", | |
f9896bf3 | 296 | "raw", |
5e3ca0ec | 297 | "hex", |
cb0f12aa | 298 | "bin", |
2a2cc8f7 | 299 | "block", |
86387f7e | 300 | "stacktrace", |
4ac3ba41 | 301 | "sched-tree", |
5e1607a0 | 302 | "trace_printk", |
b2a866f9 | 303 | "ftrace_preempt", |
9f029e83 | 304 | "branch", |
12ef7d44 | 305 | "annotate", |
02b67518 | 306 | "userstacktrace", |
b54d3de9 | 307 | "sym-userobj", |
66896a85 | 308 | "printk-msg-only", |
c4a8e8be | 309 | "context-info", |
c032ef64 | 310 | "latency-format", |
bc0c38d1 SR |
311 | NULL |
312 | }; | |
313 | ||
4fcdae83 SR |
314 | /* |
315 | * ftrace_max_lock is used to protect the swapping of buffers | |
316 | * when taking a max snapshot. The buffers themselves are | |
317 | * protected by per_cpu spinlocks. But the action of the swap | |
318 | * needs its own lock. | |
319 | * | |
320 | * This is defined as a raw_spinlock_t in order to help | |
321 | * with performance when lockdep debugging is enabled. | |
322 | */ | |
92205c23 SR |
323 | static raw_spinlock_t ftrace_max_lock = |
324 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
bc0c38d1 SR |
325 | |
326 | /* | |
327 | * Copy the new maximum trace into the separate maximum-trace | |
328 | * structure. (this way the maximum trace is permanently saved, | |
329 | * for later retrieval via /debugfs/tracing/latency_trace) | |
330 | */ | |
e309b41d | 331 | static void |
bc0c38d1 SR |
332 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
333 | { | |
334 | struct trace_array_cpu *data = tr->data[cpu]; | |
335 | ||
336 | max_tr.cpu = cpu; | |
337 | max_tr.time_start = data->preempt_timestamp; | |
338 | ||
339 | data = max_tr.data[cpu]; | |
340 | data->saved_latency = tracing_max_latency; | |
341 | ||
342 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
343 | data->pid = tsk->pid; | |
b6dff3ec | 344 | data->uid = task_uid(tsk); |
bc0c38d1 SR |
345 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
346 | data->policy = tsk->policy; | |
347 | data->rt_priority = tsk->rt_priority; | |
348 | ||
349 | /* record this tasks comm */ | |
af513098 | 350 | tracing_record_cmdline(tsk); |
bc0c38d1 SR |
351 | } |
352 | ||
6c6c2796 PP |
353 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
354 | { | |
355 | int len; | |
356 | int ret; | |
357 | ||
2dc5d12b SR |
358 | if (!cnt) |
359 | return 0; | |
360 | ||
6c6c2796 PP |
361 | if (s->len <= s->readpos) |
362 | return -EBUSY; | |
363 | ||
364 | len = s->len - s->readpos; | |
365 | if (cnt > len) | |
366 | cnt = len; | |
367 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 368 | if (ret == cnt) |
6c6c2796 PP |
369 | return -EFAULT; |
370 | ||
2dc5d12b SR |
371 | cnt -= ret; |
372 | ||
e74da523 | 373 | s->readpos += cnt; |
6c6c2796 | 374 | return cnt; |
214023c3 SR |
375 | } |
376 | ||
3c56819b EGM |
377 | ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
378 | { | |
379 | int len; | |
380 | void *ret; | |
381 | ||
382 | if (s->len <= s->readpos) | |
383 | return -EBUSY; | |
384 | ||
385 | len = s->len - s->readpos; | |
386 | if (cnt > len) | |
387 | cnt = len; | |
388 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
389 | if (!ret) | |
390 | return -EFAULT; | |
391 | ||
e74da523 | 392 | s->readpos += cnt; |
3c56819b EGM |
393 | return cnt; |
394 | } | |
395 | ||
e309b41d | 396 | static void |
214023c3 SR |
397 | trace_print_seq(struct seq_file *m, struct trace_seq *s) |
398 | { | |
399 | int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; | |
400 | ||
401 | s->buffer[len] = 0; | |
402 | seq_puts(m, s->buffer); | |
403 | ||
f9520750 | 404 | trace_seq_init(s); |
214023c3 SR |
405 | } |
406 | ||
4fcdae83 SR |
407 | /** |
408 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
409 | * @tr: tracer | |
410 | * @tsk: the task with the latency | |
411 | * @cpu: The cpu that initiated the trace. | |
412 | * | |
413 | * Flip the buffers between the @tr and the max_tr and record information | |
414 | * about which task was the cause of this latency. | |
415 | */ | |
e309b41d | 416 | void |
bc0c38d1 SR |
417 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
418 | { | |
3928a8a2 | 419 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 420 | |
4c11d7ae | 421 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 422 | __raw_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
423 | |
424 | tr->buffer = max_tr.buffer; | |
425 | max_tr.buffer = buf; | |
426 | ||
d769041f | 427 | ftrace_disable_cpu(); |
3928a8a2 | 428 | ring_buffer_reset(tr->buffer); |
d769041f | 429 | ftrace_enable_cpu(); |
bc0c38d1 SR |
430 | |
431 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 432 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
433 | } |
434 | ||
435 | /** | |
436 | * update_max_tr_single - only copy one trace over, and reset the rest | |
437 | * @tr - tracer | |
438 | * @tsk - task with the latency | |
439 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
440 | * |
441 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 442 | */ |
e309b41d | 443 | void |
bc0c38d1 SR |
444 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
445 | { | |
3928a8a2 | 446 | int ret; |
bc0c38d1 | 447 | |
4c11d7ae | 448 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 449 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 450 | |
d769041f SR |
451 | ftrace_disable_cpu(); |
452 | ||
3928a8a2 SR |
453 | ring_buffer_reset(max_tr.buffer); |
454 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); | |
455 | ||
d769041f SR |
456 | ftrace_enable_cpu(); |
457 | ||
97b17efe | 458 | WARN_ON_ONCE(ret && ret != -EAGAIN); |
bc0c38d1 SR |
459 | |
460 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 461 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
462 | } |
463 | ||
4fcdae83 SR |
464 | /** |
465 | * register_tracer - register a tracer with the ftrace system. | |
466 | * @type - the plugin for the tracer | |
467 | * | |
468 | * Register a new plugin tracer. | |
469 | */ | |
bc0c38d1 | 470 | int register_tracer(struct tracer *type) |
e7669b8e HE |
471 | __releases(kernel_lock) |
472 | __acquires(kernel_lock) | |
bc0c38d1 SR |
473 | { |
474 | struct tracer *t; | |
475 | int len; | |
476 | int ret = 0; | |
477 | ||
478 | if (!type->name) { | |
479 | pr_info("Tracer must have a name\n"); | |
480 | return -1; | |
481 | } | |
482 | ||
86fa2f60 IM |
483 | /* |
484 | * When this gets called we hold the BKL which means that | |
485 | * preemption is disabled. Various trace selftests however | |
486 | * need to disable and enable preemption for successful tests. | |
487 | * So we drop the BKL here and grab it after the tests again. | |
488 | */ | |
489 | unlock_kernel(); | |
bc0c38d1 | 490 | mutex_lock(&trace_types_lock); |
86fa2f60 | 491 | |
8e1b82e0 FW |
492 | tracing_selftest_running = true; |
493 | ||
bc0c38d1 SR |
494 | for (t = trace_types; t; t = t->next) { |
495 | if (strcmp(type->name, t->name) == 0) { | |
496 | /* already found */ | |
497 | pr_info("Trace %s already registered\n", | |
498 | type->name); | |
499 | ret = -1; | |
500 | goto out; | |
501 | } | |
502 | } | |
503 | ||
adf9f195 FW |
504 | if (!type->set_flag) |
505 | type->set_flag = &dummy_set_flag; | |
506 | if (!type->flags) | |
507 | type->flags = &dummy_tracer_flags; | |
508 | else | |
509 | if (!type->flags->opts) | |
510 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
511 | if (!type->wait_pipe) |
512 | type->wait_pipe = default_wait_pipe; | |
513 | ||
adf9f195 | 514 | |
60a11774 | 515 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 516 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 517 | struct tracer *saved_tracer = current_trace; |
60a11774 | 518 | struct trace_array *tr = &global_trace; |
60a11774 | 519 | int i; |
ff32504f | 520 | |
60a11774 SR |
521 | /* |
522 | * Run a selftest on this tracer. | |
523 | * Here we reset the trace buffer, and set the current | |
524 | * tracer to be this tracer. The tracer can then run some | |
525 | * internal tracing to verify that everything is in order. | |
526 | * If we fail, we do not register this tracer. | |
527 | */ | |
86fa2f60 | 528 | for_each_tracing_cpu(i) |
3928a8a2 | 529 | tracing_reset(tr, i); |
86fa2f60 | 530 | |
60a11774 | 531 | current_trace = type; |
60a11774 SR |
532 | /* the test is responsible for initializing and enabling */ |
533 | pr_info("Testing tracer %s: ", type->name); | |
534 | ret = type->selftest(type, tr); | |
535 | /* the test is responsible for resetting too */ | |
536 | current_trace = saved_tracer; | |
60a11774 SR |
537 | if (ret) { |
538 | printk(KERN_CONT "FAILED!\n"); | |
539 | goto out; | |
540 | } | |
1d4db00a | 541 | /* Only reset on passing, to avoid touching corrupted buffers */ |
86fa2f60 | 542 | for_each_tracing_cpu(i) |
3928a8a2 | 543 | tracing_reset(tr, i); |
86fa2f60 | 544 | |
60a11774 SR |
545 | printk(KERN_CONT "PASSED\n"); |
546 | } | |
547 | #endif | |
548 | ||
bc0c38d1 SR |
549 | type->next = trace_types; |
550 | trace_types = type; | |
551 | len = strlen(type->name); | |
552 | if (len > max_tracer_type_len) | |
553 | max_tracer_type_len = len; | |
60a11774 | 554 | |
bc0c38d1 | 555 | out: |
8e1b82e0 | 556 | tracing_selftest_running = false; |
bc0c38d1 SR |
557 | mutex_unlock(&trace_types_lock); |
558 | ||
dac74940 SR |
559 | if (ret || !default_bootup_tracer) |
560 | goto out_unlock; | |
561 | ||
562 | if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE)) | |
563 | goto out_unlock; | |
564 | ||
565 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
566 | /* Do we want this tracer to start on bootup? */ | |
567 | tracing_set_tracer(type->name); | |
568 | default_bootup_tracer = NULL; | |
569 | /* disable other selftests, since this will break it. */ | |
570 | tracing_selftest_disabled = 1; | |
b2821ae6 | 571 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
572 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
573 | type->name); | |
b2821ae6 | 574 | #endif |
b2821ae6 | 575 | |
dac74940 | 576 | out_unlock: |
b2821ae6 | 577 | lock_kernel(); |
bc0c38d1 SR |
578 | return ret; |
579 | } | |
580 | ||
581 | void unregister_tracer(struct tracer *type) | |
582 | { | |
583 | struct tracer **t; | |
584 | int len; | |
585 | ||
586 | mutex_lock(&trace_types_lock); | |
587 | for (t = &trace_types; *t; t = &(*t)->next) { | |
588 | if (*t == type) | |
589 | goto found; | |
590 | } | |
591 | pr_info("Trace %s not registered\n", type->name); | |
592 | goto out; | |
593 | ||
594 | found: | |
595 | *t = (*t)->next; | |
b5db03c4 ACM |
596 | |
597 | if (type == current_trace && tracer_enabled) { | |
598 | tracer_enabled = 0; | |
599 | tracing_stop(); | |
600 | if (current_trace->stop) | |
601 | current_trace->stop(&global_trace); | |
602 | current_trace = &nop_trace; | |
603 | } | |
604 | ||
bc0c38d1 SR |
605 | if (strlen(type->name) != max_tracer_type_len) |
606 | goto out; | |
607 | ||
608 | max_tracer_type_len = 0; | |
609 | for (t = &trace_types; *t; t = &(*t)->next) { | |
610 | len = strlen((*t)->name); | |
611 | if (len > max_tracer_type_len) | |
612 | max_tracer_type_len = len; | |
613 | } | |
614 | out: | |
615 | mutex_unlock(&trace_types_lock); | |
616 | } | |
617 | ||
3928a8a2 | 618 | void tracing_reset(struct trace_array *tr, int cpu) |
bc0c38d1 | 619 | { |
d769041f | 620 | ftrace_disable_cpu(); |
3928a8a2 | 621 | ring_buffer_reset_cpu(tr->buffer, cpu); |
d769041f | 622 | ftrace_enable_cpu(); |
bc0c38d1 SR |
623 | } |
624 | ||
213cc060 PE |
625 | void tracing_reset_online_cpus(struct trace_array *tr) |
626 | { | |
627 | int cpu; | |
628 | ||
629 | tr->time_start = ftrace_now(tr->cpu); | |
630 | ||
631 | for_each_online_cpu(cpu) | |
632 | tracing_reset(tr, cpu); | |
633 | } | |
634 | ||
bc0c38d1 | 635 | #define SAVED_CMDLINES 128 |
2c7eea4c | 636 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
637 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
638 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
639 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
640 | static int cmdline_idx; | |
efed792d | 641 | static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; |
25b0b44a | 642 | |
25b0b44a | 643 | /* temporary disable recording */ |
4fd27358 | 644 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
645 | |
646 | static void trace_init_cmdlines(void) | |
647 | { | |
2c7eea4c TG |
648 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
649 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
650 | cmdline_idx = 0; |
651 | } | |
652 | ||
0f048701 SR |
653 | static int trace_stop_count; |
654 | static DEFINE_SPINLOCK(tracing_start_lock); | |
655 | ||
69bb54ec SR |
656 | /** |
657 | * ftrace_off_permanent - disable all ftrace code permanently | |
658 | * | |
659 | * This should only be called when a serious anomally has | |
660 | * been detected. This will turn off the function tracing, | |
661 | * ring buffers, and other tracing utilites. It takes no | |
662 | * locks and can be called from any context. | |
663 | */ | |
664 | void ftrace_off_permanent(void) | |
665 | { | |
666 | tracing_disabled = 1; | |
667 | ftrace_stop(); | |
668 | tracing_off_permanent(); | |
669 | } | |
670 | ||
0f048701 SR |
671 | /** |
672 | * tracing_start - quick start of the tracer | |
673 | * | |
674 | * If tracing is enabled but was stopped by tracing_stop, | |
675 | * this will start the tracer back up. | |
676 | */ | |
677 | void tracing_start(void) | |
678 | { | |
679 | struct ring_buffer *buffer; | |
680 | unsigned long flags; | |
681 | ||
682 | if (tracing_disabled) | |
683 | return; | |
684 | ||
685 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
686 | if (--trace_stop_count) { |
687 | if (trace_stop_count < 0) { | |
688 | /* Someone screwed up their debugging */ | |
689 | WARN_ON_ONCE(1); | |
690 | trace_stop_count = 0; | |
691 | } | |
0f048701 SR |
692 | goto out; |
693 | } | |
694 | ||
695 | ||
696 | buffer = global_trace.buffer; | |
697 | if (buffer) | |
698 | ring_buffer_record_enable(buffer); | |
699 | ||
700 | buffer = max_tr.buffer; | |
701 | if (buffer) | |
702 | ring_buffer_record_enable(buffer); | |
703 | ||
704 | ftrace_start(); | |
705 | out: | |
706 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
707 | } | |
708 | ||
709 | /** | |
710 | * tracing_stop - quick stop of the tracer | |
711 | * | |
712 | * Light weight way to stop tracing. Use in conjunction with | |
713 | * tracing_start. | |
714 | */ | |
715 | void tracing_stop(void) | |
716 | { | |
717 | struct ring_buffer *buffer; | |
718 | unsigned long flags; | |
719 | ||
720 | ftrace_stop(); | |
721 | spin_lock_irqsave(&tracing_start_lock, flags); | |
722 | if (trace_stop_count++) | |
723 | goto out; | |
724 | ||
725 | buffer = global_trace.buffer; | |
726 | if (buffer) | |
727 | ring_buffer_record_disable(buffer); | |
728 | ||
729 | buffer = max_tr.buffer; | |
730 | if (buffer) | |
731 | ring_buffer_record_disable(buffer); | |
732 | ||
733 | out: | |
734 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
735 | } | |
736 | ||
e309b41d | 737 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 738 | |
e309b41d | 739 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
740 | { |
741 | unsigned map; | |
742 | unsigned idx; | |
743 | ||
744 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
745 | return; | |
746 | ||
747 | /* | |
748 | * It's not the end of the world if we don't get | |
749 | * the lock, but we also don't want to spin | |
750 | * nor do we want to disable interrupts, | |
751 | * so if we miss here, then better luck next time. | |
752 | */ | |
efed792d | 753 | if (!__raw_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
754 | return; |
755 | ||
756 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 757 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
758 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
759 | ||
760 | map = map_cmdline_to_pid[idx]; | |
2c7eea4c TG |
761 | if (map != NO_CMDLINE_MAP) |
762 | map_pid_to_cmdline[map] = NO_CMDLINE_MAP; | |
bc0c38d1 SR |
763 | |
764 | map_pid_to_cmdline[tsk->pid] = idx; | |
765 | ||
766 | cmdline_idx = idx; | |
767 | } | |
768 | ||
769 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
770 | ||
efed792d | 771 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
772 | } |
773 | ||
4ca53085 | 774 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 775 | { |
bc0c38d1 SR |
776 | unsigned map; |
777 | ||
4ca53085 SR |
778 | if (!pid) { |
779 | strcpy(comm, "<idle>"); | |
780 | return; | |
781 | } | |
bc0c38d1 | 782 | |
4ca53085 SR |
783 | if (pid > PID_MAX_DEFAULT) { |
784 | strcpy(comm, "<...>"); | |
785 | return; | |
786 | } | |
bc0c38d1 | 787 | |
4ca53085 | 788 | __raw_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 789 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
790 | if (map != NO_CMDLINE_MAP) |
791 | strcpy(comm, saved_cmdlines[map]); | |
792 | else | |
793 | strcpy(comm, "<...>"); | |
bc0c38d1 | 794 | |
4ca53085 | 795 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
796 | } |
797 | ||
e309b41d | 798 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 799 | { |
18aecd36 TG |
800 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
801 | !tracing_is_on()) | |
bc0c38d1 SR |
802 | return; |
803 | ||
804 | trace_save_cmdline(tsk); | |
805 | } | |
806 | ||
45dcd8b8 | 807 | void |
38697053 SR |
808 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
809 | int pc) | |
bc0c38d1 SR |
810 | { |
811 | struct task_struct *tsk = current; | |
bc0c38d1 | 812 | |
777e208d SR |
813 | entry->preempt_count = pc & 0xff; |
814 | entry->pid = (tsk) ? tsk->pid : 0; | |
ef18012b | 815 | entry->tgid = (tsk) ? tsk->tgid : 0; |
777e208d | 816 | entry->flags = |
9244489a | 817 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 818 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
819 | #else |
820 | TRACE_FLAG_IRQS_NOSUPPORT | | |
821 | #endif | |
bc0c38d1 SR |
822 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
823 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
824 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
825 | } | |
826 | ||
51a763dd ACM |
827 | struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr, |
828 | unsigned char type, | |
829 | unsigned long len, | |
830 | unsigned long flags, int pc) | |
831 | { | |
832 | struct ring_buffer_event *event; | |
833 | ||
834 | event = ring_buffer_lock_reserve(tr->buffer, len); | |
835 | if (event != NULL) { | |
836 | struct trace_entry *ent = ring_buffer_event_data(event); | |
837 | ||
838 | tracing_generic_entry_update(ent, flags, pc); | |
839 | ent->type = type; | |
840 | } | |
841 | ||
842 | return event; | |
843 | } | |
844 | static void ftrace_trace_stack(struct trace_array *tr, | |
845 | unsigned long flags, int skip, int pc); | |
846 | static void ftrace_trace_userstack(struct trace_array *tr, | |
847 | unsigned long flags, int pc); | |
848 | ||
849 | void trace_buffer_unlock_commit(struct trace_array *tr, | |
850 | struct ring_buffer_event *event, | |
851 | unsigned long flags, int pc) | |
852 | { | |
853 | ring_buffer_unlock_commit(tr->buffer, event); | |
854 | ||
855 | ftrace_trace_stack(tr, flags, 6, pc); | |
856 | ftrace_trace_userstack(tr, flags, pc); | |
857 | trace_wake_up(); | |
858 | } | |
859 | ||
ef5580d0 SR |
860 | struct ring_buffer_event * |
861 | trace_current_buffer_lock_reserve(unsigned char type, unsigned long len, | |
862 | unsigned long flags, int pc) | |
863 | { | |
864 | return trace_buffer_lock_reserve(&global_trace, | |
865 | type, len, flags, pc); | |
866 | } | |
867 | ||
868 | void trace_current_buffer_unlock_commit(struct ring_buffer_event *event, | |
869 | unsigned long flags, int pc) | |
870 | { | |
871 | return trace_buffer_unlock_commit(&global_trace, event, flags, pc); | |
872 | } | |
873 | ||
e309b41d | 874 | void |
7be42151 | 875 | trace_function(struct trace_array *tr, |
38697053 SR |
876 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
877 | int pc) | |
bc0c38d1 | 878 | { |
3928a8a2 | 879 | struct ring_buffer_event *event; |
777e208d | 880 | struct ftrace_entry *entry; |
bc0c38d1 | 881 | |
d769041f SR |
882 | /* If we are reading the ring buffer, don't trace */ |
883 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
884 | return; | |
885 | ||
51a763dd ACM |
886 | event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry), |
887 | flags, pc); | |
3928a8a2 SR |
888 | if (!event) |
889 | return; | |
890 | entry = ring_buffer_event_data(event); | |
777e208d SR |
891 | entry->ip = ip; |
892 | entry->parent_ip = parent_ip; | |
0a987751 | 893 | ring_buffer_unlock_commit(tr->buffer, event); |
bc0c38d1 SR |
894 | } |
895 | ||
fb52607a | 896 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
287b6e68 | 897 | static void __trace_graph_entry(struct trace_array *tr, |
287b6e68 FW |
898 | struct ftrace_graph_ent *trace, |
899 | unsigned long flags, | |
900 | int pc) | |
901 | { | |
902 | struct ring_buffer_event *event; | |
903 | struct ftrace_graph_ent_entry *entry; | |
287b6e68 FW |
904 | |
905 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
906 | return; | |
907 | ||
51a763dd ACM |
908 | event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_ENT, |
909 | sizeof(*entry), flags, pc); | |
287b6e68 FW |
910 | if (!event) |
911 | return; | |
912 | entry = ring_buffer_event_data(event); | |
287b6e68 | 913 | entry->graph_ent = *trace; |
0a987751 | 914 | ring_buffer_unlock_commit(global_trace.buffer, event); |
287b6e68 FW |
915 | } |
916 | ||
917 | static void __trace_graph_return(struct trace_array *tr, | |
fb52607a | 918 | struct ftrace_graph_ret *trace, |
15e6cb36 FW |
919 | unsigned long flags, |
920 | int pc) | |
921 | { | |
922 | struct ring_buffer_event *event; | |
287b6e68 | 923 | struct ftrace_graph_ret_entry *entry; |
15e6cb36 FW |
924 | |
925 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
926 | return; | |
927 | ||
51a763dd ACM |
928 | event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_RET, |
929 | sizeof(*entry), flags, pc); | |
15e6cb36 FW |
930 | if (!event) |
931 | return; | |
932 | entry = ring_buffer_event_data(event); | |
287b6e68 | 933 | entry->ret = *trace; |
0a987751 | 934 | ring_buffer_unlock_commit(global_trace.buffer, event); |
15e6cb36 FW |
935 | } |
936 | #endif | |
937 | ||
e309b41d | 938 | void |
2e0f5761 | 939 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
940 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
941 | int pc) | |
2e0f5761 IM |
942 | { |
943 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 944 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
945 | } |
946 | ||
53614991 | 947 | static void __ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
948 | unsigned long flags, |
949 | int skip, int pc) | |
86387f7e | 950 | { |
c2c80529 | 951 | #ifdef CONFIG_STACKTRACE |
3928a8a2 | 952 | struct ring_buffer_event *event; |
777e208d | 953 | struct stack_entry *entry; |
86387f7e IM |
954 | struct stack_trace trace; |
955 | ||
51a763dd ACM |
956 | event = trace_buffer_lock_reserve(tr, TRACE_STACK, |
957 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
958 | if (!event) |
959 | return; | |
960 | entry = ring_buffer_event_data(event); | |
777e208d | 961 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
962 | |
963 | trace.nr_entries = 0; | |
964 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
965 | trace.skip = skip; | |
777e208d | 966 | trace.entries = entry->caller; |
86387f7e IM |
967 | |
968 | save_stack_trace(&trace); | |
0a987751 | 969 | ring_buffer_unlock_commit(tr->buffer, event); |
c2c80529 | 970 | #endif |
f0a920d5 IM |
971 | } |
972 | ||
53614991 | 973 | static void ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
974 | unsigned long flags, |
975 | int skip, int pc) | |
976 | { | |
977 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
978 | return; | |
979 | ||
7be42151 | 980 | __ftrace_trace_stack(tr, flags, skip, pc); |
53614991 SR |
981 | } |
982 | ||
38697053 | 983 | void __trace_stack(struct trace_array *tr, |
38697053 | 984 | unsigned long flags, |
53614991 | 985 | int skip, int pc) |
38697053 | 986 | { |
7be42151 | 987 | __ftrace_trace_stack(tr, flags, skip, pc); |
38697053 SR |
988 | } |
989 | ||
02b67518 | 990 | static void ftrace_trace_userstack(struct trace_array *tr, |
7be42151 | 991 | unsigned long flags, int pc) |
02b67518 | 992 | { |
c7425acb | 993 | #ifdef CONFIG_STACKTRACE |
8d7c6a96 | 994 | struct ring_buffer_event *event; |
02b67518 TE |
995 | struct userstack_entry *entry; |
996 | struct stack_trace trace; | |
02b67518 TE |
997 | |
998 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
999 | return; | |
1000 | ||
51a763dd ACM |
1001 | event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK, |
1002 | sizeof(*entry), flags, pc); | |
02b67518 TE |
1003 | if (!event) |
1004 | return; | |
1005 | entry = ring_buffer_event_data(event); | |
02b67518 TE |
1006 | |
1007 | memset(&entry->caller, 0, sizeof(entry->caller)); | |
1008 | ||
1009 | trace.nr_entries = 0; | |
1010 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1011 | trace.skip = 0; | |
1012 | trace.entries = entry->caller; | |
1013 | ||
1014 | save_stack_trace_user(&trace); | |
0a987751 | 1015 | ring_buffer_unlock_commit(tr->buffer, event); |
c7425acb | 1016 | #endif |
02b67518 TE |
1017 | } |
1018 | ||
4fd27358 HE |
1019 | #ifdef UNUSED |
1020 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1021 | { |
7be42151 | 1022 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1023 | } |
4fd27358 | 1024 | #endif /* UNUSED */ |
02b67518 | 1025 | |
38697053 | 1026 | static void |
7be42151 | 1027 | ftrace_trace_special(void *__tr, |
38697053 SR |
1028 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1029 | int pc) | |
a4feb834 | 1030 | { |
3928a8a2 | 1031 | struct ring_buffer_event *event; |
a4feb834 | 1032 | struct trace_array *tr = __tr; |
777e208d | 1033 | struct special_entry *entry; |
a4feb834 | 1034 | |
51a763dd ACM |
1035 | event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL, |
1036 | sizeof(*entry), 0, pc); | |
3928a8a2 SR |
1037 | if (!event) |
1038 | return; | |
1039 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1040 | entry->arg1 = arg1; |
1041 | entry->arg2 = arg2; | |
1042 | entry->arg3 = arg3; | |
51a763dd | 1043 | trace_buffer_unlock_commit(tr, event, 0, pc); |
a4feb834 IM |
1044 | } |
1045 | ||
38697053 SR |
1046 | void |
1047 | __trace_special(void *__tr, void *__data, | |
1048 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1049 | { | |
7be42151 | 1050 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1051 | } |
1052 | ||
e309b41d | 1053 | void |
bc0c38d1 | 1054 | tracing_sched_switch_trace(struct trace_array *tr, |
86387f7e IM |
1055 | struct task_struct *prev, |
1056 | struct task_struct *next, | |
38697053 | 1057 | unsigned long flags, int pc) |
bc0c38d1 | 1058 | { |
3928a8a2 | 1059 | struct ring_buffer_event *event; |
777e208d | 1060 | struct ctx_switch_entry *entry; |
bc0c38d1 | 1061 | |
51a763dd ACM |
1062 | event = trace_buffer_lock_reserve(tr, TRACE_CTX, |
1063 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1064 | if (!event) |
1065 | return; | |
1066 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1067 | entry->prev_pid = prev->pid; |
1068 | entry->prev_prio = prev->prio; | |
1069 | entry->prev_state = prev->state; | |
1070 | entry->next_pid = next->pid; | |
1071 | entry->next_prio = next->prio; | |
1072 | entry->next_state = next->state; | |
1073 | entry->next_cpu = task_cpu(next); | |
51a763dd | 1074 | trace_buffer_unlock_commit(tr, event, flags, pc); |
bc0c38d1 SR |
1075 | } |
1076 | ||
57422797 IM |
1077 | void |
1078 | tracing_sched_wakeup_trace(struct trace_array *tr, | |
86387f7e IM |
1079 | struct task_struct *wakee, |
1080 | struct task_struct *curr, | |
38697053 | 1081 | unsigned long flags, int pc) |
57422797 | 1082 | { |
3928a8a2 | 1083 | struct ring_buffer_event *event; |
777e208d | 1084 | struct ctx_switch_entry *entry; |
57422797 | 1085 | |
51a763dd ACM |
1086 | event = trace_buffer_lock_reserve(tr, TRACE_WAKE, |
1087 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1088 | if (!event) |
1089 | return; | |
1090 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1091 | entry->prev_pid = curr->pid; |
1092 | entry->prev_prio = curr->prio; | |
1093 | entry->prev_state = curr->state; | |
1094 | entry->next_pid = wakee->pid; | |
1095 | entry->next_prio = wakee->prio; | |
1096 | entry->next_state = wakee->state; | |
1097 | entry->next_cpu = task_cpu(wakee); | |
6eaaa5d5 FW |
1098 | |
1099 | ring_buffer_unlock_commit(tr->buffer, event); | |
1100 | ftrace_trace_stack(tr, flags, 6, pc); | |
1101 | ftrace_trace_userstack(tr, flags, pc); | |
57422797 IM |
1102 | } |
1103 | ||
4902f884 SR |
1104 | void |
1105 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1106 | { | |
1107 | struct trace_array *tr = &global_trace; | |
1108 | struct trace_array_cpu *data; | |
5aa1ba6a | 1109 | unsigned long flags; |
4902f884 | 1110 | int cpu; |
38697053 | 1111 | int pc; |
4902f884 | 1112 | |
c76f0694 | 1113 | if (tracing_disabled) |
4902f884 SR |
1114 | return; |
1115 | ||
38697053 | 1116 | pc = preempt_count(); |
5aa1ba6a | 1117 | local_irq_save(flags); |
4902f884 SR |
1118 | cpu = raw_smp_processor_id(); |
1119 | data = tr->data[cpu]; | |
4902f884 | 1120 | |
5aa1ba6a | 1121 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1122 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1123 | |
5aa1ba6a SR |
1124 | atomic_dec(&data->disabled); |
1125 | local_irq_restore(flags); | |
4902f884 SR |
1126 | } |
1127 | ||
fb52607a | 1128 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e49dc19c | 1129 | int trace_graph_entry(struct ftrace_graph_ent *trace) |
15e6cb36 FW |
1130 | { |
1131 | struct trace_array *tr = &global_trace; | |
1132 | struct trace_array_cpu *data; | |
1133 | unsigned long flags; | |
1134 | long disabled; | |
1135 | int cpu; | |
1136 | int pc; | |
1137 | ||
804a6851 SR |
1138 | if (!ftrace_trace_task(current)) |
1139 | return 0; | |
1140 | ||
ea4e2bc4 SR |
1141 | if (!ftrace_graph_addr(trace->func)) |
1142 | return 0; | |
1143 | ||
a5e25883 | 1144 | local_irq_save(flags); |
15e6cb36 FW |
1145 | cpu = raw_smp_processor_id(); |
1146 | data = tr->data[cpu]; | |
1147 | disabled = atomic_inc_return(&data->disabled); | |
1148 | if (likely(disabled == 1)) { | |
1149 | pc = preempt_count(); | |
7be42151 | 1150 | __trace_graph_entry(tr, trace, flags, pc); |
287b6e68 | 1151 | } |
ea4e2bc4 SR |
1152 | /* Only do the atomic if it is not already set */ |
1153 | if (!test_tsk_trace_graph(current)) | |
1154 | set_tsk_trace_graph(current); | |
287b6e68 | 1155 | atomic_dec(&data->disabled); |
a5e25883 | 1156 | local_irq_restore(flags); |
e49dc19c SR |
1157 | |
1158 | return 1; | |
287b6e68 FW |
1159 | } |
1160 | ||
1161 | void trace_graph_return(struct ftrace_graph_ret *trace) | |
1162 | { | |
1163 | struct trace_array *tr = &global_trace; | |
1164 | struct trace_array_cpu *data; | |
1165 | unsigned long flags; | |
1166 | long disabled; | |
1167 | int cpu; | |
1168 | int pc; | |
1169 | ||
a5e25883 | 1170 | local_irq_save(flags); |
287b6e68 FW |
1171 | cpu = raw_smp_processor_id(); |
1172 | data = tr->data[cpu]; | |
1173 | disabled = atomic_inc_return(&data->disabled); | |
1174 | if (likely(disabled == 1)) { | |
1175 | pc = preempt_count(); | |
7be42151 | 1176 | __trace_graph_return(tr, trace, flags, pc); |
15e6cb36 | 1177 | } |
ea4e2bc4 SR |
1178 | if (!trace->depth) |
1179 | clear_tsk_trace_graph(current); | |
15e6cb36 | 1180 | atomic_dec(&data->disabled); |
a5e25883 | 1181 | local_irq_restore(flags); |
15e6cb36 | 1182 | } |
fb52607a | 1183 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
15e6cb36 | 1184 | |
769b0441 FW |
1185 | |
1186 | /** | |
48ead020 | 1187 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1188 | * |
1189 | */ | |
48ead020 | 1190 | int trace_vbprintk(unsigned long ip, int depth, const char *fmt, va_list args) |
769b0441 | 1191 | { |
80370cb7 SR |
1192 | static raw_spinlock_t trace_buf_lock = |
1193 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
769b0441 FW |
1194 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1195 | ||
1196 | struct ring_buffer_event *event; | |
1197 | struct trace_array *tr = &global_trace; | |
1198 | struct trace_array_cpu *data; | |
48ead020 | 1199 | struct bprint_entry *entry; |
769b0441 FW |
1200 | unsigned long flags; |
1201 | int resched; | |
1202 | int cpu, len = 0, size, pc; | |
1203 | ||
1204 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1205 | return 0; | |
1206 | ||
1207 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1208 | pause_graph_tracing(); | |
1209 | ||
1210 | pc = preempt_count(); | |
1211 | resched = ftrace_preempt_disable(); | |
1212 | cpu = raw_smp_processor_id(); | |
1213 | data = tr->data[cpu]; | |
1214 | ||
1215 | if (unlikely(atomic_read(&data->disabled))) | |
1216 | goto out; | |
1217 | ||
80370cb7 SR |
1218 | /* Lockdep uses trace_printk for lock tracing */ |
1219 | local_irq_save(flags); | |
1220 | __raw_spin_lock(&trace_buf_lock); | |
769b0441 FW |
1221 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1222 | ||
1223 | if (len > TRACE_BUF_SIZE || len < 0) | |
1224 | goto out_unlock; | |
1225 | ||
1226 | size = sizeof(*entry) + sizeof(u32) * len; | |
48ead020 | 1227 | event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc); |
769b0441 FW |
1228 | if (!event) |
1229 | goto out_unlock; | |
1230 | entry = ring_buffer_event_data(event); | |
1231 | entry->ip = ip; | |
1232 | entry->depth = depth; | |
1233 | entry->fmt = fmt; | |
1234 | ||
1235 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
1236 | ring_buffer_unlock_commit(tr->buffer, event); | |
1237 | ||
1238 | out_unlock: | |
80370cb7 SR |
1239 | __raw_spin_unlock(&trace_buf_lock); |
1240 | local_irq_restore(flags); | |
769b0441 FW |
1241 | |
1242 | out: | |
1243 | ftrace_preempt_enable(resched); | |
1244 | unpause_graph_tracing(); | |
1245 | ||
1246 | return len; | |
1247 | } | |
48ead020 FW |
1248 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1249 | ||
1250 | int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args) | |
1251 | { | |
1252 | static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; | |
1253 | static char trace_buf[TRACE_BUF_SIZE]; | |
1254 | ||
1255 | struct ring_buffer_event *event; | |
1256 | struct trace_array *tr = &global_trace; | |
1257 | struct trace_array_cpu *data; | |
1258 | int cpu, len = 0, size, pc; | |
1259 | struct print_entry *entry; | |
1260 | unsigned long irq_flags; | |
1261 | ||
1262 | if (tracing_disabled || tracing_selftest_running) | |
1263 | return 0; | |
1264 | ||
1265 | pc = preempt_count(); | |
1266 | preempt_disable_notrace(); | |
1267 | cpu = raw_smp_processor_id(); | |
1268 | data = tr->data[cpu]; | |
1269 | ||
1270 | if (unlikely(atomic_read(&data->disabled))) | |
1271 | goto out; | |
1272 | ||
1273 | pause_graph_tracing(); | |
1274 | raw_local_irq_save(irq_flags); | |
1275 | __raw_spin_lock(&trace_buf_lock); | |
1276 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); | |
1277 | ||
1278 | len = min(len, TRACE_BUF_SIZE-1); | |
1279 | trace_buf[len] = 0; | |
1280 | ||
1281 | size = sizeof(*entry) + len + 1; | |
1282 | event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc); | |
1283 | if (!event) | |
1284 | goto out_unlock; | |
1285 | entry = ring_buffer_event_data(event); | |
1286 | entry->ip = ip; | |
1287 | entry->depth = depth; | |
1288 | ||
1289 | memcpy(&entry->buf, trace_buf, len); | |
1290 | entry->buf[len] = 0; | |
1291 | ring_buffer_unlock_commit(tr->buffer, event); | |
1292 | ||
1293 | out_unlock: | |
1294 | __raw_spin_unlock(&trace_buf_lock); | |
1295 | raw_local_irq_restore(irq_flags); | |
1296 | unpause_graph_tracing(); | |
1297 | out: | |
1298 | preempt_enable_notrace(); | |
1299 | ||
1300 | return len; | |
1301 | } | |
769b0441 FW |
1302 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1303 | ||
bc0c38d1 SR |
1304 | enum trace_file_type { |
1305 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1306 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1307 | }; |
1308 | ||
e2ac8ef5 | 1309 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1310 | { |
d769041f SR |
1311 | /* Don't allow ftrace to trace into the ring buffers */ |
1312 | ftrace_disable_cpu(); | |
1313 | ||
5a90f577 | 1314 | iter->idx++; |
d769041f SR |
1315 | if (iter->buffer_iter[iter->cpu]) |
1316 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1317 | ||
1318 | ftrace_enable_cpu(); | |
5a90f577 SR |
1319 | } |
1320 | ||
e309b41d | 1321 | static struct trace_entry * |
3928a8a2 | 1322 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1323 | { |
3928a8a2 SR |
1324 | struct ring_buffer_event *event; |
1325 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1326 | |
d769041f SR |
1327 | /* Don't allow ftrace to trace into the ring buffers */ |
1328 | ftrace_disable_cpu(); | |
1329 | ||
1330 | if (buf_iter) | |
1331 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1332 | else | |
1333 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1334 | ||
1335 | ftrace_enable_cpu(); | |
1336 | ||
3928a8a2 | 1337 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1338 | } |
d769041f | 1339 | |
dd0e545f | 1340 | static struct trace_entry * |
3928a8a2 | 1341 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1342 | { |
3928a8a2 | 1343 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1344 | struct trace_entry *ent, *next = NULL; |
b04cc6b1 | 1345 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1346 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1347 | int next_cpu = -1; |
1348 | int cpu; | |
1349 | ||
b04cc6b1 FW |
1350 | /* |
1351 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1352 | * all cpu and peek directly. | |
1353 | */ | |
1354 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1355 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1356 | return NULL; | |
1357 | ent = peek_next_entry(iter, cpu_file, ent_ts); | |
1358 | if (ent_cpu) | |
1359 | *ent_cpu = cpu_file; | |
1360 | ||
1361 | return ent; | |
1362 | } | |
1363 | ||
ab46428c | 1364 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1365 | |
3928a8a2 SR |
1366 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1367 | continue; | |
dd0e545f | 1368 | |
3928a8a2 | 1369 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1370 | |
cdd31cd2 IM |
1371 | /* |
1372 | * Pick the entry with the smallest timestamp: | |
1373 | */ | |
3928a8a2 | 1374 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1375 | next = ent; |
1376 | next_cpu = cpu; | |
3928a8a2 | 1377 | next_ts = ts; |
bc0c38d1 SR |
1378 | } |
1379 | } | |
1380 | ||
1381 | if (ent_cpu) | |
1382 | *ent_cpu = next_cpu; | |
1383 | ||
3928a8a2 SR |
1384 | if (ent_ts) |
1385 | *ent_ts = next_ts; | |
1386 | ||
bc0c38d1 SR |
1387 | return next; |
1388 | } | |
1389 | ||
dd0e545f | 1390 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1391 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1392 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1393 | { |
3928a8a2 | 1394 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1395 | } |
1396 | ||
1397 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1398 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1399 | { | |
3928a8a2 | 1400 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1401 | |
3928a8a2 | 1402 | if (iter->ent) |
e2ac8ef5 | 1403 | trace_iterator_increment(iter); |
dd0e545f | 1404 | |
3928a8a2 | 1405 | return iter->ent ? iter : NULL; |
b3806b43 | 1406 | } |
bc0c38d1 | 1407 | |
e309b41d | 1408 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1409 | { |
d769041f SR |
1410 | /* Don't allow ftrace to trace into the ring buffers */ |
1411 | ftrace_disable_cpu(); | |
3928a8a2 | 1412 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1413 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1414 | } |
1415 | ||
e309b41d | 1416 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1417 | { |
1418 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1419 | int i = (int)*pos; |
4e3c3333 | 1420 | void *ent; |
bc0c38d1 SR |
1421 | |
1422 | (*pos)++; | |
1423 | ||
1424 | /* can't go backwards */ | |
1425 | if (iter->idx > i) | |
1426 | return NULL; | |
1427 | ||
1428 | if (iter->idx < 0) | |
1429 | ent = find_next_entry_inc(iter); | |
1430 | else | |
1431 | ent = iter; | |
1432 | ||
1433 | while (ent && iter->idx < i) | |
1434 | ent = find_next_entry_inc(iter); | |
1435 | ||
1436 | iter->pos = *pos; | |
1437 | ||
bc0c38d1 SR |
1438 | return ent; |
1439 | } | |
1440 | ||
d7350c3f FW |
1441 | /* |
1442 | * No necessary locking here. The worst thing which can | |
1443 | * happen is loosing events consumed at the same time | |
1444 | * by a trace_pipe reader. | |
1445 | * Other than that, we don't risk to crash the ring buffer | |
1446 | * because it serializes the readers. | |
1447 | * | |
1448 | * The current tracer is copied to avoid a global locking | |
1449 | * all around. | |
1450 | */ | |
bc0c38d1 SR |
1451 | static void *s_start(struct seq_file *m, loff_t *pos) |
1452 | { | |
1453 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1454 | static struct tracer *old_tracer; |
b04cc6b1 | 1455 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1456 | void *p = NULL; |
1457 | loff_t l = 0; | |
3928a8a2 | 1458 | int cpu; |
bc0c38d1 | 1459 | |
d7350c3f | 1460 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1461 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1462 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1463 | old_tracer = current_trace; | |
1464 | *iter->trace = *current_trace; | |
d15f57f2 | 1465 | } |
d7350c3f | 1466 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1467 | |
1468 | atomic_inc(&trace_record_cmdline_disabled); | |
1469 | ||
bc0c38d1 SR |
1470 | if (*pos != iter->pos) { |
1471 | iter->ent = NULL; | |
1472 | iter->cpu = 0; | |
1473 | iter->idx = -1; | |
1474 | ||
d769041f SR |
1475 | ftrace_disable_cpu(); |
1476 | ||
b04cc6b1 FW |
1477 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1478 | for_each_tracing_cpu(cpu) | |
1479 | ring_buffer_iter_reset(iter->buffer_iter[cpu]); | |
1480 | } else | |
1481 | ring_buffer_iter_reset(iter->buffer_iter[cpu_file]); | |
1482 | ||
bc0c38d1 | 1483 | |
d769041f SR |
1484 | ftrace_enable_cpu(); |
1485 | ||
bc0c38d1 SR |
1486 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1487 | ; | |
1488 | ||
1489 | } else { | |
4c11d7ae | 1490 | l = *pos - 1; |
bc0c38d1 SR |
1491 | p = s_next(m, p, &l); |
1492 | } | |
1493 | ||
1494 | return p; | |
1495 | } | |
1496 | ||
1497 | static void s_stop(struct seq_file *m, void *p) | |
1498 | { | |
bc0c38d1 | 1499 | atomic_dec(&trace_record_cmdline_disabled); |
bc0c38d1 SR |
1500 | } |
1501 | ||
e309b41d | 1502 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1503 | { |
a6168353 ME |
1504 | seq_puts(m, "# _------=> CPU# \n"); |
1505 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1506 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1507 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1508 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1509 | seq_puts(m, "# |||| / \n"); | |
1510 | seq_puts(m, "# ||||| delay \n"); | |
1511 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1512 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1513 | } |
1514 | ||
e309b41d | 1515 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1516 | { |
a6168353 ME |
1517 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1518 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1519 | } |
1520 | ||
1521 | ||
e309b41d | 1522 | static void |
bc0c38d1 SR |
1523 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1524 | { | |
1525 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1526 | struct trace_array *tr = iter->tr; | |
1527 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1528 | struct tracer *type = current_trace; | |
3928a8a2 SR |
1529 | unsigned long total; |
1530 | unsigned long entries; | |
bc0c38d1 SR |
1531 | const char *name = "preemption"; |
1532 | ||
1533 | if (type) | |
1534 | name = type->name; | |
1535 | ||
3928a8a2 SR |
1536 | entries = ring_buffer_entries(iter->tr->buffer); |
1537 | total = entries + | |
1538 | ring_buffer_overruns(iter->tr->buffer); | |
bc0c38d1 | 1539 | |
888b55dc | 1540 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1541 | name, UTS_RELEASE); |
888b55dc | 1542 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1543 | "---------------------------------\n"); |
888b55dc | 1544 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1545 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1546 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1547 | entries, |
4c11d7ae | 1548 | total, |
bc0c38d1 SR |
1549 | tr->cpu, |
1550 | #if defined(CONFIG_PREEMPT_NONE) | |
1551 | "server", | |
1552 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1553 | "desktop", | |
b5c21b45 | 1554 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1555 | "preempt", |
1556 | #else | |
1557 | "unknown", | |
1558 | #endif | |
1559 | /* These are reserved for later use */ | |
1560 | 0, 0, 0, 0); | |
1561 | #ifdef CONFIG_SMP | |
1562 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1563 | #else | |
1564 | seq_puts(m, ")\n"); | |
1565 | #endif | |
888b55dc KM |
1566 | seq_puts(m, "# -----------------\n"); |
1567 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1568 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1569 | data->comm, data->pid, data->uid, data->nice, | |
1570 | data->policy, data->rt_priority); | |
888b55dc | 1571 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1572 | |
1573 | if (data->critical_start) { | |
888b55dc | 1574 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1575 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1576 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1577 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1578 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1579 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1580 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1581 | } |
1582 | ||
888b55dc | 1583 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1584 | } |
1585 | ||
a309720c SR |
1586 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1587 | { | |
1588 | struct trace_seq *s = &iter->seq; | |
1589 | ||
12ef7d44 SR |
1590 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1591 | return; | |
1592 | ||
1593 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1594 | return; | |
1595 | ||
4462344e | 1596 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1597 | return; |
1598 | ||
4462344e | 1599 | cpumask_set_cpu(iter->cpu, iter->started); |
a309720c SR |
1600 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", iter->cpu); |
1601 | } | |
1602 | ||
2c4f035f | 1603 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1604 | { |
214023c3 | 1605 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1606 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1607 | struct trace_entry *entry; |
f633cef0 | 1608 | struct trace_event *event; |
bc0c38d1 | 1609 | |
4e3c3333 | 1610 | entry = iter->ent; |
dd0e545f | 1611 | |
a309720c SR |
1612 | test_cpu_buff_start(iter); |
1613 | ||
c4a8e8be | 1614 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1615 | |
c4a8e8be | 1616 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1617 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1618 | if (!trace_print_lat_context(iter)) | |
1619 | goto partial; | |
1620 | } else { | |
1621 | if (!trace_print_context(iter)) | |
1622 | goto partial; | |
1623 | } | |
c4a8e8be | 1624 | } |
bc0c38d1 | 1625 | |
268ccda0 | 1626 | if (event) |
d9793bd8 ACM |
1627 | return event->trace(iter, sym_flags); |
1628 | ||
1629 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1630 | goto partial; | |
02b67518 | 1631 | |
2c4f035f | 1632 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1633 | partial: |
1634 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1635 | } |
1636 | ||
2c4f035f | 1637 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1638 | { |
1639 | struct trace_seq *s = &iter->seq; | |
1640 | struct trace_entry *entry; | |
f633cef0 | 1641 | struct trace_event *event; |
f9896bf3 IM |
1642 | |
1643 | entry = iter->ent; | |
dd0e545f | 1644 | |
c4a8e8be | 1645 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1646 | if (!trace_seq_printf(s, "%d %d %llu ", |
1647 | entry->pid, iter->cpu, iter->ts)) | |
1648 | goto partial; | |
c4a8e8be | 1649 | } |
f9896bf3 | 1650 | |
f633cef0 | 1651 | event = ftrace_find_event(entry->type); |
268ccda0 | 1652 | if (event) |
d9793bd8 ACM |
1653 | return event->raw(iter, 0); |
1654 | ||
1655 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1656 | goto partial; | |
777e208d | 1657 | |
2c4f035f | 1658 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1659 | partial: |
1660 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1661 | } |
1662 | ||
2c4f035f | 1663 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1664 | { |
1665 | struct trace_seq *s = &iter->seq; | |
1666 | unsigned char newline = '\n'; | |
1667 | struct trace_entry *entry; | |
f633cef0 | 1668 | struct trace_event *event; |
5e3ca0ec IM |
1669 | |
1670 | entry = iter->ent; | |
dd0e545f | 1671 | |
c4a8e8be FW |
1672 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1673 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1674 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1675 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1676 | } | |
5e3ca0ec | 1677 | |
f633cef0 | 1678 | event = ftrace_find_event(entry->type); |
268ccda0 | 1679 | if (event) { |
ae7462b4 | 1680 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1681 | if (ret != TRACE_TYPE_HANDLED) |
1682 | return ret; | |
1683 | } | |
7104f300 | 1684 | |
5e3ca0ec IM |
1685 | SEQ_PUT_FIELD_RET(s, newline); |
1686 | ||
2c4f035f | 1687 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1688 | } |
1689 | ||
48ead020 FW |
1690 | static enum print_line_t print_bprintk_msg_only(struct trace_iterator *iter) |
1691 | { | |
1692 | struct trace_seq *s = &iter->seq; | |
1693 | struct trace_entry *entry = iter->ent; | |
1694 | struct bprint_entry *field; | |
1695 | int ret; | |
1696 | ||
1697 | trace_assign_type(field, entry); | |
1698 | ||
1699 | ret = trace_seq_bprintf(s, field->fmt, field->buf); | |
1700 | if (!ret) | |
1701 | return TRACE_TYPE_PARTIAL_LINE; | |
1702 | ||
1703 | return TRACE_TYPE_HANDLED; | |
1704 | } | |
1705 | ||
66896a85 FW |
1706 | static enum print_line_t print_printk_msg_only(struct trace_iterator *iter) |
1707 | { | |
1708 | struct trace_seq *s = &iter->seq; | |
1709 | struct trace_entry *entry = iter->ent; | |
1710 | struct print_entry *field; | |
1711 | int ret; | |
1712 | ||
1713 | trace_assign_type(field, entry); | |
1714 | ||
48ead020 | 1715 | ret = trace_seq_printf(s, "%s", field->buf); |
66896a85 FW |
1716 | if (!ret) |
1717 | return TRACE_TYPE_PARTIAL_LINE; | |
1718 | ||
66896a85 FW |
1719 | return TRACE_TYPE_HANDLED; |
1720 | } | |
1721 | ||
2c4f035f | 1722 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1723 | { |
1724 | struct trace_seq *s = &iter->seq; | |
1725 | struct trace_entry *entry; | |
f633cef0 | 1726 | struct trace_event *event; |
cb0f12aa IM |
1727 | |
1728 | entry = iter->ent; | |
dd0e545f | 1729 | |
c4a8e8be FW |
1730 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1731 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1732 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1733 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1734 | } | |
cb0f12aa | 1735 | |
f633cef0 | 1736 | event = ftrace_find_event(entry->type); |
268ccda0 | 1737 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1738 | } |
1739 | ||
bc0c38d1 SR |
1740 | static int trace_empty(struct trace_iterator *iter) |
1741 | { | |
bc0c38d1 SR |
1742 | int cpu; |
1743 | ||
9aba60fe SR |
1744 | /* If we are looking at one CPU buffer, only check that one */ |
1745 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1746 | cpu = iter->cpu_file; | |
1747 | if (iter->buffer_iter[cpu]) { | |
1748 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1749 | return 0; | |
1750 | } else { | |
1751 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1752 | return 0; | |
1753 | } | |
1754 | return 1; | |
1755 | } | |
1756 | ||
ab46428c | 1757 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1758 | if (iter->buffer_iter[cpu]) { |
1759 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1760 | return 0; | |
1761 | } else { | |
1762 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1763 | return 0; | |
1764 | } | |
bc0c38d1 | 1765 | } |
d769041f | 1766 | |
797d3712 | 1767 | return 1; |
bc0c38d1 SR |
1768 | } |
1769 | ||
2c4f035f | 1770 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1771 | { |
2c4f035f FW |
1772 | enum print_line_t ret; |
1773 | ||
1774 | if (iter->trace && iter->trace->print_line) { | |
1775 | ret = iter->trace->print_line(iter); | |
1776 | if (ret != TRACE_TYPE_UNHANDLED) | |
1777 | return ret; | |
1778 | } | |
72829bc3 | 1779 | |
48ead020 FW |
1780 | if (iter->ent->type == TRACE_BPRINT && |
1781 | trace_flags & TRACE_ITER_PRINTK && | |
1782 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
1783 | return print_bprintk_msg_only(iter); | |
1784 | ||
66896a85 FW |
1785 | if (iter->ent->type == TRACE_PRINT && |
1786 | trace_flags & TRACE_ITER_PRINTK && | |
1787 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
1788 | return print_printk_msg_only(iter); | |
1789 | ||
cb0f12aa IM |
1790 | if (trace_flags & TRACE_ITER_BIN) |
1791 | return print_bin_fmt(iter); | |
1792 | ||
5e3ca0ec IM |
1793 | if (trace_flags & TRACE_ITER_HEX) |
1794 | return print_hex_fmt(iter); | |
1795 | ||
f9896bf3 IM |
1796 | if (trace_flags & TRACE_ITER_RAW) |
1797 | return print_raw_fmt(iter); | |
1798 | ||
f9896bf3 IM |
1799 | return print_trace_fmt(iter); |
1800 | } | |
1801 | ||
bc0c38d1 SR |
1802 | static int s_show(struct seq_file *m, void *v) |
1803 | { | |
1804 | struct trace_iterator *iter = v; | |
1805 | ||
1806 | if (iter->ent == NULL) { | |
1807 | if (iter->tr) { | |
1808 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1809 | seq_puts(m, "#\n"); | |
1810 | } | |
8bba1bf5 MM |
1811 | if (iter->trace && iter->trace->print_header) |
1812 | iter->trace->print_header(m); | |
1813 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
1814 | /* print nothing if the buffers are empty */ |
1815 | if (trace_empty(iter)) | |
1816 | return 0; | |
1817 | print_trace_header(m, iter); | |
1818 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1819 | print_lat_help_header(m); | |
1820 | } else { | |
1821 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1822 | print_func_help_header(m); | |
1823 | } | |
1824 | } else { | |
f9896bf3 | 1825 | print_trace_line(iter); |
214023c3 | 1826 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1827 | } |
1828 | ||
1829 | return 0; | |
1830 | } | |
1831 | ||
1832 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1833 | .start = s_start, |
1834 | .next = s_next, | |
1835 | .stop = s_stop, | |
1836 | .show = s_show, | |
bc0c38d1 SR |
1837 | }; |
1838 | ||
e309b41d | 1839 | static struct trace_iterator * |
85a2f9b4 | 1840 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 1841 | { |
b04cc6b1 | 1842 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 1843 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 1844 | struct trace_iterator *iter; |
3928a8a2 | 1845 | struct seq_file *m; |
85a2f9b4 | 1846 | int cpu, ret; |
bc0c38d1 | 1847 | |
85a2f9b4 SR |
1848 | if (tracing_disabled) |
1849 | return ERR_PTR(-ENODEV); | |
60a11774 | 1850 | |
bc0c38d1 | 1851 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
1852 | if (!iter) |
1853 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 1854 | |
d7350c3f FW |
1855 | /* |
1856 | * We make a copy of the current tracer to avoid concurrent | |
1857 | * changes on it while we are reading. | |
1858 | */ | |
bc0c38d1 | 1859 | mutex_lock(&trace_types_lock); |
d7350c3f | 1860 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 1861 | if (!iter->trace) |
d7350c3f | 1862 | goto fail; |
85a2f9b4 | 1863 | |
d7350c3f FW |
1864 | if (current_trace) |
1865 | *iter->trace = *current_trace; | |
1866 | ||
bc0c38d1 SR |
1867 | if (current_trace && current_trace->print_max) |
1868 | iter->tr = &max_tr; | |
1869 | else | |
b04cc6b1 | 1870 | iter->tr = &global_trace; |
bc0c38d1 | 1871 | iter->pos = -1; |
d7350c3f | 1872 | mutex_init(&iter->mutex); |
b04cc6b1 | 1873 | iter->cpu_file = cpu_file; |
bc0c38d1 | 1874 | |
8bba1bf5 MM |
1875 | /* Notify the tracer early; before we stop tracing. */ |
1876 | if (iter->trace && iter->trace->open) | |
a93751ca | 1877 | iter->trace->open(iter); |
8bba1bf5 | 1878 | |
12ef7d44 SR |
1879 | /* Annotate start of buffers if we had overruns */ |
1880 | if (ring_buffer_overruns(iter->tr->buffer)) | |
1881 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
1882 | ||
b04cc6b1 FW |
1883 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
1884 | for_each_tracing_cpu(cpu) { | |
12ef7d44 | 1885 | |
b04cc6b1 FW |
1886 | iter->buffer_iter[cpu] = |
1887 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
b04cc6b1 FW |
1888 | } |
1889 | } else { | |
1890 | cpu = iter->cpu_file; | |
3928a8a2 | 1891 | iter->buffer_iter[cpu] = |
b04cc6b1 | 1892 | ring_buffer_read_start(iter->tr->buffer, cpu); |
3928a8a2 SR |
1893 | } |
1894 | ||
bc0c38d1 | 1895 | /* TODO stop tracer */ |
85a2f9b4 SR |
1896 | ret = seq_open(file, &tracer_seq_ops); |
1897 | if (ret < 0) { | |
1898 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 1899 | goto fail_buffer; |
85a2f9b4 | 1900 | } |
bc0c38d1 | 1901 | |
3928a8a2 SR |
1902 | m = file->private_data; |
1903 | m->private = iter; | |
bc0c38d1 | 1904 | |
3928a8a2 | 1905 | /* stop the trace while dumping */ |
9036990d | 1906 | tracing_stop(); |
3928a8a2 | 1907 | |
bc0c38d1 SR |
1908 | mutex_unlock(&trace_types_lock); |
1909 | ||
bc0c38d1 | 1910 | return iter; |
3928a8a2 SR |
1911 | |
1912 | fail_buffer: | |
1913 | for_each_tracing_cpu(cpu) { | |
1914 | if (iter->buffer_iter[cpu]) | |
1915 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1916 | } | |
d7350c3f | 1917 | fail: |
3928a8a2 | 1918 | mutex_unlock(&trace_types_lock); |
d7350c3f | 1919 | kfree(iter->trace); |
0bb943c7 | 1920 | kfree(iter); |
3928a8a2 | 1921 | |
85a2f9b4 | 1922 | return fail_ret; |
bc0c38d1 SR |
1923 | } |
1924 | ||
1925 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1926 | { | |
60a11774 SR |
1927 | if (tracing_disabled) |
1928 | return -ENODEV; | |
1929 | ||
bc0c38d1 SR |
1930 | filp->private_data = inode->i_private; |
1931 | return 0; | |
1932 | } | |
1933 | ||
4fd27358 | 1934 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
1935 | { |
1936 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1937 | struct trace_iterator *iter = m->private; | |
3928a8a2 | 1938 | int cpu; |
bc0c38d1 SR |
1939 | |
1940 | mutex_lock(&trace_types_lock); | |
3928a8a2 SR |
1941 | for_each_tracing_cpu(cpu) { |
1942 | if (iter->buffer_iter[cpu]) | |
1943 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1944 | } | |
1945 | ||
bc0c38d1 SR |
1946 | if (iter->trace && iter->trace->close) |
1947 | iter->trace->close(iter); | |
1948 | ||
1949 | /* reenable tracing if it was previously enabled */ | |
9036990d | 1950 | tracing_start(); |
bc0c38d1 SR |
1951 | mutex_unlock(&trace_types_lock); |
1952 | ||
1953 | seq_release(inode, file); | |
d7350c3f FW |
1954 | mutex_destroy(&iter->mutex); |
1955 | kfree(iter->trace); | |
bc0c38d1 SR |
1956 | kfree(iter); |
1957 | return 0; | |
1958 | } | |
1959 | ||
1960 | static int tracing_open(struct inode *inode, struct file *file) | |
1961 | { | |
85a2f9b4 SR |
1962 | struct trace_iterator *iter; |
1963 | int ret = 0; | |
bc0c38d1 | 1964 | |
85a2f9b4 SR |
1965 | iter = __tracing_open(inode, file); |
1966 | if (IS_ERR(iter)) | |
1967 | ret = PTR_ERR(iter); | |
c032ef64 | 1968 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) |
bc0c38d1 SR |
1969 | iter->iter_flags |= TRACE_FILE_LAT_FMT; |
1970 | ||
1971 | return ret; | |
1972 | } | |
1973 | ||
e309b41d | 1974 | static void * |
bc0c38d1 SR |
1975 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1976 | { | |
1977 | struct tracer *t = m->private; | |
1978 | ||
1979 | (*pos)++; | |
1980 | ||
1981 | if (t) | |
1982 | t = t->next; | |
1983 | ||
1984 | m->private = t; | |
1985 | ||
1986 | return t; | |
1987 | } | |
1988 | ||
1989 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1990 | { | |
1991 | struct tracer *t = m->private; | |
1992 | loff_t l = 0; | |
1993 | ||
1994 | mutex_lock(&trace_types_lock); | |
1995 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
1996 | ; | |
1997 | ||
1998 | return t; | |
1999 | } | |
2000 | ||
2001 | static void t_stop(struct seq_file *m, void *p) | |
2002 | { | |
2003 | mutex_unlock(&trace_types_lock); | |
2004 | } | |
2005 | ||
2006 | static int t_show(struct seq_file *m, void *v) | |
2007 | { | |
2008 | struct tracer *t = v; | |
2009 | ||
2010 | if (!t) | |
2011 | return 0; | |
2012 | ||
2013 | seq_printf(m, "%s", t->name); | |
2014 | if (t->next) | |
2015 | seq_putc(m, ' '); | |
2016 | else | |
2017 | seq_putc(m, '\n'); | |
2018 | ||
2019 | return 0; | |
2020 | } | |
2021 | ||
2022 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
2023 | .start = t_start, |
2024 | .next = t_next, | |
2025 | .stop = t_stop, | |
2026 | .show = t_show, | |
bc0c38d1 SR |
2027 | }; |
2028 | ||
2029 | static int show_traces_open(struct inode *inode, struct file *file) | |
2030 | { | |
2031 | int ret; | |
2032 | ||
60a11774 SR |
2033 | if (tracing_disabled) |
2034 | return -ENODEV; | |
2035 | ||
bc0c38d1 SR |
2036 | ret = seq_open(file, &show_traces_seq_ops); |
2037 | if (!ret) { | |
2038 | struct seq_file *m = file->private_data; | |
2039 | m->private = trace_types; | |
2040 | } | |
2041 | ||
2042 | return ret; | |
2043 | } | |
2044 | ||
5e2336a0 | 2045 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2046 | .open = tracing_open, |
2047 | .read = seq_read, | |
2048 | .llseek = seq_lseek, | |
2049 | .release = tracing_release, | |
bc0c38d1 SR |
2050 | }; |
2051 | ||
5e2336a0 | 2052 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2053 | .open = show_traces_open, |
2054 | .read = seq_read, | |
2055 | .release = seq_release, | |
2056 | }; | |
2057 | ||
36dfe925 IM |
2058 | /* |
2059 | * Only trace on a CPU if the bitmask is set: | |
2060 | */ | |
9e01c1b7 | 2061 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2062 | |
2063 | /* | |
2064 | * The tracer itself will not take this lock, but still we want | |
2065 | * to provide a consistent cpumask to user-space: | |
2066 | */ | |
2067 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2068 | ||
2069 | /* | |
2070 | * Temporary storage for the character representation of the | |
2071 | * CPU bitmask (and one more byte for the newline): | |
2072 | */ | |
2073 | static char mask_str[NR_CPUS + 1]; | |
2074 | ||
c7078de1 IM |
2075 | static ssize_t |
2076 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2077 | size_t count, loff_t *ppos) | |
2078 | { | |
36dfe925 | 2079 | int len; |
c7078de1 IM |
2080 | |
2081 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2082 | |
9e01c1b7 | 2083 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2084 | if (count - len < 2) { |
2085 | count = -EINVAL; | |
2086 | goto out_err; | |
2087 | } | |
2088 | len += sprintf(mask_str + len, "\n"); | |
2089 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2090 | ||
2091 | out_err: | |
c7078de1 IM |
2092 | mutex_unlock(&tracing_cpumask_update_lock); |
2093 | ||
2094 | return count; | |
2095 | } | |
2096 | ||
2097 | static ssize_t | |
2098 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2099 | size_t count, loff_t *ppos) | |
2100 | { | |
36dfe925 | 2101 | int err, cpu; |
9e01c1b7 RR |
2102 | cpumask_var_t tracing_cpumask_new; |
2103 | ||
2104 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2105 | return -ENOMEM; | |
c7078de1 IM |
2106 | |
2107 | mutex_lock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2108 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2109 | if (err) |
36dfe925 IM |
2110 | goto err_unlock; |
2111 | ||
a5e25883 | 2112 | local_irq_disable(); |
92205c23 | 2113 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 2114 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2115 | /* |
2116 | * Increase/decrease the disabled counter if we are | |
2117 | * about to flip a bit in the cpumask: | |
2118 | */ | |
9e01c1b7 RR |
2119 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2120 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2121 | atomic_inc(&global_trace.data[cpu]->disabled); |
2122 | } | |
9e01c1b7 RR |
2123 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2124 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2125 | atomic_dec(&global_trace.data[cpu]->disabled); |
2126 | } | |
2127 | } | |
92205c23 | 2128 | __raw_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2129 | local_irq_enable(); |
36dfe925 | 2130 | |
9e01c1b7 | 2131 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2132 | |
2133 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2134 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2135 | |
2136 | return count; | |
36dfe925 IM |
2137 | |
2138 | err_unlock: | |
2139 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2140 | free_cpumask_var(tracing_cpumask); |
36dfe925 IM |
2141 | |
2142 | return err; | |
c7078de1 IM |
2143 | } |
2144 | ||
5e2336a0 | 2145 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2146 | .open = tracing_open_generic, |
2147 | .read = tracing_cpumask_read, | |
2148 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2149 | }; |
2150 | ||
2151 | static ssize_t | |
ee6bce52 | 2152 | tracing_trace_options_read(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
2153 | size_t cnt, loff_t *ppos) |
2154 | { | |
d8e83d26 SR |
2155 | struct tracer_opt *trace_opts; |
2156 | u32 tracer_flags; | |
2157 | int len = 0; | |
bc0c38d1 SR |
2158 | char *buf; |
2159 | int r = 0; | |
d8e83d26 | 2160 | int i; |
adf9f195 | 2161 | |
bc0c38d1 | 2162 | |
c3706f00 | 2163 | /* calculate max size */ |
bc0c38d1 SR |
2164 | for (i = 0; trace_options[i]; i++) { |
2165 | len += strlen(trace_options[i]); | |
5c6a3ae1 | 2166 | len += 3; /* "no" and newline */ |
bc0c38d1 SR |
2167 | } |
2168 | ||
d8e83d26 SR |
2169 | mutex_lock(&trace_types_lock); |
2170 | tracer_flags = current_trace->flags->val; | |
2171 | trace_opts = current_trace->flags->opts; | |
2172 | ||
adf9f195 FW |
2173 | /* |
2174 | * Increase the size with names of options specific | |
2175 | * of the current tracer. | |
2176 | */ | |
2177 | for (i = 0; trace_opts[i].name; i++) { | |
2178 | len += strlen(trace_opts[i].name); | |
5c6a3ae1 | 2179 | len += 3; /* "no" and newline */ |
adf9f195 FW |
2180 | } |
2181 | ||
bc0c38d1 SR |
2182 | /* +2 for \n and \0 */ |
2183 | buf = kmalloc(len + 2, GFP_KERNEL); | |
d8e83d26 SR |
2184 | if (!buf) { |
2185 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 2186 | return -ENOMEM; |
d8e83d26 | 2187 | } |
bc0c38d1 SR |
2188 | |
2189 | for (i = 0; trace_options[i]; i++) { | |
2190 | if (trace_flags & (1 << i)) | |
5c6a3ae1 | 2191 | r += sprintf(buf + r, "%s\n", trace_options[i]); |
bc0c38d1 | 2192 | else |
5c6a3ae1 | 2193 | r += sprintf(buf + r, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2194 | } |
2195 | ||
adf9f195 FW |
2196 | for (i = 0; trace_opts[i].name; i++) { |
2197 | if (tracer_flags & trace_opts[i].bit) | |
5c6a3ae1 | 2198 | r += sprintf(buf + r, "%s\n", |
adf9f195 FW |
2199 | trace_opts[i].name); |
2200 | else | |
5c6a3ae1 | 2201 | r += sprintf(buf + r, "no%s\n", |
adf9f195 FW |
2202 | trace_opts[i].name); |
2203 | } | |
d8e83d26 | 2204 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2205 | |
bc0c38d1 SR |
2206 | WARN_ON(r >= len + 2); |
2207 | ||
36dfe925 | 2208 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2209 | |
2210 | kfree(buf); | |
bc0c38d1 SR |
2211 | return r; |
2212 | } | |
2213 | ||
adf9f195 FW |
2214 | /* Try to assign a tracer specific option */ |
2215 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2216 | { | |
2217 | struct tracer_flags *trace_flags = trace->flags; | |
2218 | struct tracer_opt *opts = NULL; | |
2219 | int ret = 0, i = 0; | |
2220 | int len; | |
2221 | ||
2222 | for (i = 0; trace_flags->opts[i].name; i++) { | |
2223 | opts = &trace_flags->opts[i]; | |
2224 | len = strlen(opts->name); | |
2225 | ||
2226 | if (strncmp(cmp, opts->name, len) == 0) { | |
2227 | ret = trace->set_flag(trace_flags->val, | |
2228 | opts->bit, !neg); | |
2229 | break; | |
2230 | } | |
2231 | } | |
2232 | /* Not found */ | |
2233 | if (!trace_flags->opts[i].name) | |
2234 | return -EINVAL; | |
2235 | ||
2236 | /* Refused to handle */ | |
2237 | if (ret) | |
2238 | return ret; | |
2239 | ||
2240 | if (neg) | |
2241 | trace_flags->val &= ~opts->bit; | |
2242 | else | |
2243 | trace_flags->val |= opts->bit; | |
2244 | ||
2245 | return 0; | |
2246 | } | |
2247 | ||
bc0c38d1 | 2248 | static ssize_t |
ee6bce52 | 2249 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2250 | size_t cnt, loff_t *ppos) |
2251 | { | |
2252 | char buf[64]; | |
2253 | char *cmp = buf; | |
2254 | int neg = 0; | |
adf9f195 | 2255 | int ret; |
bc0c38d1 SR |
2256 | int i; |
2257 | ||
cffae437 SR |
2258 | if (cnt >= sizeof(buf)) |
2259 | return -EINVAL; | |
bc0c38d1 SR |
2260 | |
2261 | if (copy_from_user(&buf, ubuf, cnt)) | |
2262 | return -EFAULT; | |
2263 | ||
2264 | buf[cnt] = 0; | |
2265 | ||
2266 | if (strncmp(buf, "no", 2) == 0) { | |
2267 | neg = 1; | |
2268 | cmp += 2; | |
2269 | } | |
2270 | ||
2271 | for (i = 0; trace_options[i]; i++) { | |
2272 | int len = strlen(trace_options[i]); | |
2273 | ||
2274 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
2275 | if (neg) | |
2276 | trace_flags &= ~(1 << i); | |
2277 | else | |
2278 | trace_flags |= (1 << i); | |
2279 | break; | |
2280 | } | |
2281 | } | |
adf9f195 FW |
2282 | |
2283 | /* If no option could be set, test the specific tracer options */ | |
2284 | if (!trace_options[i]) { | |
d8e83d26 | 2285 | mutex_lock(&trace_types_lock); |
adf9f195 | 2286 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2287 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2288 | if (ret) |
2289 | return ret; | |
2290 | } | |
bc0c38d1 SR |
2291 | |
2292 | filp->f_pos += cnt; | |
2293 | ||
2294 | return cnt; | |
2295 | } | |
2296 | ||
5e2336a0 | 2297 | static const struct file_operations tracing_iter_fops = { |
c7078de1 | 2298 | .open = tracing_open_generic, |
ee6bce52 SR |
2299 | .read = tracing_trace_options_read, |
2300 | .write = tracing_trace_options_write, | |
bc0c38d1 SR |
2301 | }; |
2302 | ||
7bd2f24c IM |
2303 | static const char readme_msg[] = |
2304 | "tracing mini-HOWTO:\n\n" | |
2305 | "# mkdir /debug\n" | |
2306 | "# mount -t debugfs nodev /debug\n\n" | |
2307 | "# cat /debug/tracing/available_tracers\n" | |
2308 | "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n" | |
2309 | "# cat /debug/tracing/current_tracer\n" | |
2310 | "none\n" | |
2311 | "# echo sched_switch > /debug/tracing/current_tracer\n" | |
2312 | "# cat /debug/tracing/current_tracer\n" | |
2313 | "sched_switch\n" | |
ee6bce52 | 2314 | "# cat /debug/tracing/trace_options\n" |
7bd2f24c | 2315 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
ee6bce52 | 2316 | "# echo print-parent > /debug/tracing/trace_options\n" |
7bd2f24c IM |
2317 | "# echo 1 > /debug/tracing/tracing_enabled\n" |
2318 | "# cat /debug/tracing/trace > /tmp/trace.txt\n" | |
2319 | "echo 0 > /debug/tracing/tracing_enabled\n" | |
2320 | ; | |
2321 | ||
2322 | static ssize_t | |
2323 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2324 | size_t cnt, loff_t *ppos) | |
2325 | { | |
2326 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2327 | readme_msg, strlen(readme_msg)); | |
2328 | } | |
2329 | ||
5e2336a0 | 2330 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
2331 | .open = tracing_open_generic, |
2332 | .read = tracing_readme_read, | |
7bd2f24c IM |
2333 | }; |
2334 | ||
bc0c38d1 SR |
2335 | static ssize_t |
2336 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2337 | size_t cnt, loff_t *ppos) | |
2338 | { | |
bc0c38d1 SR |
2339 | char buf[64]; |
2340 | int r; | |
2341 | ||
9036990d | 2342 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2343 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2344 | } |
2345 | ||
2346 | static ssize_t | |
2347 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2348 | size_t cnt, loff_t *ppos) | |
2349 | { | |
2350 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2351 | char buf[64]; |
5e39841c | 2352 | unsigned long val; |
c6caeeb1 | 2353 | int ret; |
bc0c38d1 | 2354 | |
cffae437 SR |
2355 | if (cnt >= sizeof(buf)) |
2356 | return -EINVAL; | |
bc0c38d1 SR |
2357 | |
2358 | if (copy_from_user(&buf, ubuf, cnt)) | |
2359 | return -EFAULT; | |
2360 | ||
2361 | buf[cnt] = 0; | |
2362 | ||
c6caeeb1 SR |
2363 | ret = strict_strtoul(buf, 10, &val); |
2364 | if (ret < 0) | |
2365 | return ret; | |
bc0c38d1 SR |
2366 | |
2367 | val = !!val; | |
2368 | ||
2369 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2370 | if (tracer_enabled ^ val) { |
2371 | if (val) { | |
bc0c38d1 | 2372 | tracer_enabled = 1; |
9036990d SR |
2373 | if (current_trace->start) |
2374 | current_trace->start(tr); | |
2375 | tracing_start(); | |
2376 | } else { | |
bc0c38d1 | 2377 | tracer_enabled = 0; |
9036990d SR |
2378 | tracing_stop(); |
2379 | if (current_trace->stop) | |
2380 | current_trace->stop(tr); | |
2381 | } | |
bc0c38d1 SR |
2382 | } |
2383 | mutex_unlock(&trace_types_lock); | |
2384 | ||
2385 | filp->f_pos += cnt; | |
2386 | ||
2387 | return cnt; | |
2388 | } | |
2389 | ||
2390 | static ssize_t | |
2391 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2392 | size_t cnt, loff_t *ppos) | |
2393 | { | |
2394 | char buf[max_tracer_type_len+2]; | |
2395 | int r; | |
2396 | ||
2397 | mutex_lock(&trace_types_lock); | |
2398 | if (current_trace) | |
2399 | r = sprintf(buf, "%s\n", current_trace->name); | |
2400 | else | |
2401 | r = sprintf(buf, "\n"); | |
2402 | mutex_unlock(&trace_types_lock); | |
2403 | ||
4bf39a94 | 2404 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2405 | } |
2406 | ||
b6f11df2 ACM |
2407 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2408 | { | |
2409 | tracing_reset_online_cpus(tr); | |
2410 | return t->init(tr); | |
2411 | } | |
2412 | ||
73c5162a SR |
2413 | static int tracing_resize_ring_buffer(unsigned long size) |
2414 | { | |
2415 | int ret; | |
2416 | ||
2417 | /* | |
2418 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2419 | * we use the size that was given, and we can forget about |
2420 | * expanding it later. | |
73c5162a SR |
2421 | */ |
2422 | ring_buffer_expanded = 1; | |
2423 | ||
2424 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2425 | if (ret < 0) | |
2426 | return ret; | |
2427 | ||
2428 | ret = ring_buffer_resize(max_tr.buffer, size); | |
2429 | if (ret < 0) { | |
2430 | int r; | |
2431 | ||
2432 | r = ring_buffer_resize(global_trace.buffer, | |
2433 | global_trace.entries); | |
2434 | if (r < 0) { | |
a123c52b SR |
2435 | /* |
2436 | * AARGH! We are left with different | |
2437 | * size max buffer!!!! | |
2438 | * The max buffer is our "snapshot" buffer. | |
2439 | * When a tracer needs a snapshot (one of the | |
2440 | * latency tracers), it swaps the max buffer | |
2441 | * with the saved snap shot. We succeeded to | |
2442 | * update the size of the main buffer, but failed to | |
2443 | * update the size of the max buffer. But when we tried | |
2444 | * to reset the main buffer to the original size, we | |
2445 | * failed there too. This is very unlikely to | |
2446 | * happen, but if it does, warn and kill all | |
2447 | * tracing. | |
2448 | */ | |
73c5162a SR |
2449 | WARN_ON(1); |
2450 | tracing_disabled = 1; | |
2451 | } | |
2452 | return ret; | |
2453 | } | |
2454 | ||
2455 | global_trace.entries = size; | |
2456 | ||
2457 | return ret; | |
2458 | } | |
2459 | ||
1852fcce SR |
2460 | /** |
2461 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2462 | * | |
2463 | * To save on memory when the tracing is never used on a system with it | |
2464 | * configured in. The ring buffers are set to a minimum size. But once | |
2465 | * a user starts to use the tracing facility, then they need to grow | |
2466 | * to their default size. | |
2467 | * | |
2468 | * This function is to be called when a tracer is about to be used. | |
2469 | */ | |
2470 | int tracing_update_buffers(void) | |
2471 | { | |
2472 | int ret = 0; | |
2473 | ||
1027fcb2 | 2474 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2475 | if (!ring_buffer_expanded) |
2476 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2477 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2478 | |
2479 | return ret; | |
2480 | } | |
2481 | ||
577b785f SR |
2482 | struct trace_option_dentry; |
2483 | ||
2484 | static struct trace_option_dentry * | |
2485 | create_trace_option_files(struct tracer *tracer); | |
2486 | ||
2487 | static void | |
2488 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2489 | ||
b2821ae6 | 2490 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2491 | { |
577b785f | 2492 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2493 | struct trace_array *tr = &global_trace; |
2494 | struct tracer *t; | |
d9e54076 | 2495 | int ret = 0; |
bc0c38d1 | 2496 | |
1027fcb2 SR |
2497 | mutex_lock(&trace_types_lock); |
2498 | ||
73c5162a SR |
2499 | if (!ring_buffer_expanded) { |
2500 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2501 | if (ret < 0) | |
59f586db | 2502 | goto out; |
73c5162a SR |
2503 | ret = 0; |
2504 | } | |
2505 | ||
bc0c38d1 SR |
2506 | for (t = trace_types; t; t = t->next) { |
2507 | if (strcmp(t->name, buf) == 0) | |
2508 | break; | |
2509 | } | |
c2931e05 FW |
2510 | if (!t) { |
2511 | ret = -EINVAL; | |
2512 | goto out; | |
2513 | } | |
2514 | if (t == current_trace) | |
bc0c38d1 SR |
2515 | goto out; |
2516 | ||
9f029e83 | 2517 | trace_branch_disable(); |
bc0c38d1 SR |
2518 | if (current_trace && current_trace->reset) |
2519 | current_trace->reset(tr); | |
2520 | ||
577b785f SR |
2521 | destroy_trace_option_files(topts); |
2522 | ||
bc0c38d1 | 2523 | current_trace = t; |
577b785f SR |
2524 | |
2525 | topts = create_trace_option_files(current_trace); | |
2526 | ||
1c80025a | 2527 | if (t->init) { |
b6f11df2 | 2528 | ret = tracer_init(t, tr); |
1c80025a FW |
2529 | if (ret) |
2530 | goto out; | |
2531 | } | |
bc0c38d1 | 2532 | |
9f029e83 | 2533 | trace_branch_enable(tr); |
bc0c38d1 SR |
2534 | out: |
2535 | mutex_unlock(&trace_types_lock); | |
2536 | ||
d9e54076 PZ |
2537 | return ret; |
2538 | } | |
2539 | ||
2540 | static ssize_t | |
2541 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2542 | size_t cnt, loff_t *ppos) | |
2543 | { | |
2544 | char buf[max_tracer_type_len+1]; | |
2545 | int i; | |
2546 | size_t ret; | |
e6e7a65a FW |
2547 | int err; |
2548 | ||
2549 | ret = cnt; | |
d9e54076 PZ |
2550 | |
2551 | if (cnt > max_tracer_type_len) | |
2552 | cnt = max_tracer_type_len; | |
2553 | ||
2554 | if (copy_from_user(&buf, ubuf, cnt)) | |
2555 | return -EFAULT; | |
2556 | ||
2557 | buf[cnt] = 0; | |
2558 | ||
2559 | /* strip ending whitespace. */ | |
2560 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2561 | buf[i] = 0; | |
2562 | ||
e6e7a65a FW |
2563 | err = tracing_set_tracer(buf); |
2564 | if (err) | |
2565 | return err; | |
d9e54076 | 2566 | |
e6e7a65a | 2567 | filp->f_pos += ret; |
bc0c38d1 | 2568 | |
c2931e05 | 2569 | return ret; |
bc0c38d1 SR |
2570 | } |
2571 | ||
2572 | static ssize_t | |
2573 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2574 | size_t cnt, loff_t *ppos) | |
2575 | { | |
2576 | unsigned long *ptr = filp->private_data; | |
2577 | char buf[64]; | |
2578 | int r; | |
2579 | ||
cffae437 | 2580 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2581 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2582 | if (r > sizeof(buf)) |
2583 | r = sizeof(buf); | |
4bf39a94 | 2584 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2585 | } |
2586 | ||
2587 | static ssize_t | |
2588 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2589 | size_t cnt, loff_t *ppos) | |
2590 | { | |
5e39841c | 2591 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2592 | char buf[64]; |
5e39841c | 2593 | unsigned long val; |
c6caeeb1 | 2594 | int ret; |
bc0c38d1 | 2595 | |
cffae437 SR |
2596 | if (cnt >= sizeof(buf)) |
2597 | return -EINVAL; | |
bc0c38d1 SR |
2598 | |
2599 | if (copy_from_user(&buf, ubuf, cnt)) | |
2600 | return -EFAULT; | |
2601 | ||
2602 | buf[cnt] = 0; | |
2603 | ||
c6caeeb1 SR |
2604 | ret = strict_strtoul(buf, 10, &val); |
2605 | if (ret < 0) | |
2606 | return ret; | |
bc0c38d1 SR |
2607 | |
2608 | *ptr = val * 1000; | |
2609 | ||
2610 | return cnt; | |
2611 | } | |
2612 | ||
b3806b43 SR |
2613 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2614 | { | |
b04cc6b1 | 2615 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2616 | struct trace_iterator *iter; |
b04cc6b1 | 2617 | int ret = 0; |
b3806b43 SR |
2618 | |
2619 | if (tracing_disabled) | |
2620 | return -ENODEV; | |
2621 | ||
b04cc6b1 FW |
2622 | mutex_lock(&trace_types_lock); |
2623 | ||
2624 | /* We only allow one reader per cpu */ | |
2625 | if (cpu_file == TRACE_PIPE_ALL_CPU) { | |
2626 | if (!cpumask_empty(tracing_reader_cpumask)) { | |
2627 | ret = -EBUSY; | |
2628 | goto out; | |
2629 | } | |
2630 | cpumask_setall(tracing_reader_cpumask); | |
2631 | } else { | |
2632 | if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask)) | |
2633 | cpumask_set_cpu(cpu_file, tracing_reader_cpumask); | |
2634 | else { | |
2635 | ret = -EBUSY; | |
2636 | goto out; | |
2637 | } | |
b3806b43 SR |
2638 | } |
2639 | ||
2640 | /* create a buffer to store the information to pass to userspace */ | |
2641 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2642 | if (!iter) { |
2643 | ret = -ENOMEM; | |
2644 | goto out; | |
2645 | } | |
b3806b43 | 2646 | |
d7350c3f FW |
2647 | /* |
2648 | * We make a copy of the current tracer to avoid concurrent | |
2649 | * changes on it while we are reading. | |
2650 | */ | |
2651 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
2652 | if (!iter->trace) { | |
2653 | ret = -ENOMEM; | |
2654 | goto fail; | |
2655 | } | |
2656 | if (current_trace) | |
2657 | *iter->trace = *current_trace; | |
2658 | ||
4462344e | 2659 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 2660 | ret = -ENOMEM; |
d7350c3f | 2661 | goto fail; |
4462344e RR |
2662 | } |
2663 | ||
a309720c | 2664 | /* trace pipe does not show start of buffer */ |
4462344e | 2665 | cpumask_setall(iter->started); |
a309720c | 2666 | |
b04cc6b1 | 2667 | iter->cpu_file = cpu_file; |
b3806b43 | 2668 | iter->tr = &global_trace; |
d7350c3f | 2669 | mutex_init(&iter->mutex); |
b3806b43 SR |
2670 | filp->private_data = iter; |
2671 | ||
107bad8b SR |
2672 | if (iter->trace->pipe_open) |
2673 | iter->trace->pipe_open(iter); | |
107bad8b | 2674 | |
b04cc6b1 FW |
2675 | out: |
2676 | mutex_unlock(&trace_types_lock); | |
2677 | return ret; | |
d7350c3f FW |
2678 | |
2679 | fail: | |
2680 | kfree(iter->trace); | |
2681 | kfree(iter); | |
2682 | mutex_unlock(&trace_types_lock); | |
2683 | return ret; | |
b3806b43 SR |
2684 | } |
2685 | ||
2686 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2687 | { | |
2688 | struct trace_iterator *iter = file->private_data; | |
2689 | ||
b04cc6b1 FW |
2690 | mutex_lock(&trace_types_lock); |
2691 | ||
2692 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) | |
2693 | cpumask_clear(tracing_reader_cpumask); | |
2694 | else | |
2695 | cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); | |
2696 | ||
2697 | mutex_unlock(&trace_types_lock); | |
2698 | ||
4462344e | 2699 | free_cpumask_var(iter->started); |
d7350c3f FW |
2700 | mutex_destroy(&iter->mutex); |
2701 | kfree(iter->trace); | |
b3806b43 | 2702 | kfree(iter); |
b3806b43 SR |
2703 | |
2704 | return 0; | |
2705 | } | |
2706 | ||
2a2cc8f7 SSP |
2707 | static unsigned int |
2708 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2709 | { | |
2710 | struct trace_iterator *iter = filp->private_data; | |
2711 | ||
2712 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2713 | /* | |
2714 | * Always select as readable when in blocking mode | |
2715 | */ | |
2716 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2717 | } else { |
2a2cc8f7 SSP |
2718 | if (!trace_empty(iter)) |
2719 | return POLLIN | POLLRDNORM; | |
2720 | poll_wait(filp, &trace_wait, poll_table); | |
2721 | if (!trace_empty(iter)) | |
2722 | return POLLIN | POLLRDNORM; | |
2723 | ||
2724 | return 0; | |
2725 | } | |
2726 | } | |
2727 | ||
6eaaa5d5 FW |
2728 | |
2729 | void default_wait_pipe(struct trace_iterator *iter) | |
2730 | { | |
2731 | DEFINE_WAIT(wait); | |
2732 | ||
2733 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
2734 | ||
2735 | if (trace_empty(iter)) | |
2736 | schedule(); | |
2737 | ||
2738 | finish_wait(&trace_wait, &wait); | |
2739 | } | |
2740 | ||
2741 | /* | |
2742 | * This is a make-shift waitqueue. | |
2743 | * A tracer might use this callback on some rare cases: | |
2744 | * | |
2745 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
2746 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
2747 | * 2) the function tracers, trace all functions, we don't want | |
2748 | * the overhead of calling wake_up and friends | |
2749 | * (and tracing them too) | |
2750 | * | |
2751 | * Anyway, this is really very primitive wakeup. | |
2752 | */ | |
2753 | void poll_wait_pipe(struct trace_iterator *iter) | |
2754 | { | |
2755 | set_current_state(TASK_INTERRUPTIBLE); | |
2756 | /* sleep for 100 msecs, and try again. */ | |
2757 | schedule_timeout(HZ / 10); | |
2758 | } | |
2759 | ||
ff98781b EGM |
2760 | /* Must be called with trace_types_lock mutex held. */ |
2761 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
2762 | { |
2763 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 2764 | |
b3806b43 | 2765 | while (trace_empty(iter)) { |
2dc8f095 | 2766 | |
107bad8b | 2767 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 2768 | return -EAGAIN; |
107bad8b | 2769 | } |
2dc8f095 | 2770 | |
d7350c3f | 2771 | mutex_unlock(&iter->mutex); |
107bad8b | 2772 | |
6eaaa5d5 | 2773 | iter->trace->wait_pipe(iter); |
b3806b43 | 2774 | |
d7350c3f | 2775 | mutex_lock(&iter->mutex); |
107bad8b | 2776 | |
6eaaa5d5 | 2777 | if (signal_pending(current)) |
ff98781b | 2778 | return -EINTR; |
b3806b43 SR |
2779 | |
2780 | /* | |
2781 | * We block until we read something and tracing is disabled. | |
2782 | * We still block if tracing is disabled, but we have never | |
2783 | * read anything. This allows a user to cat this file, and | |
2784 | * then enable tracing. But after we have read something, | |
2785 | * we give an EOF when tracing is again disabled. | |
2786 | * | |
2787 | * iter->pos will be 0 if we haven't read anything. | |
2788 | */ | |
2789 | if (!tracer_enabled && iter->pos) | |
2790 | break; | |
b3806b43 SR |
2791 | } |
2792 | ||
ff98781b EGM |
2793 | return 1; |
2794 | } | |
2795 | ||
2796 | /* | |
2797 | * Consumer reader. | |
2798 | */ | |
2799 | static ssize_t | |
2800 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2801 | size_t cnt, loff_t *ppos) | |
2802 | { | |
2803 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 2804 | static struct tracer *old_tracer; |
ff98781b EGM |
2805 | ssize_t sret; |
2806 | ||
2807 | /* return any leftover data */ | |
2808 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
2809 | if (sret != -EBUSY) | |
2810 | return sret; | |
2811 | ||
f9520750 | 2812 | trace_seq_init(&iter->seq); |
ff98781b | 2813 | |
d7350c3f | 2814 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 2815 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2816 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2817 | old_tracer = current_trace; | |
2818 | *iter->trace = *current_trace; | |
2819 | } | |
2820 | mutex_unlock(&trace_types_lock); | |
2821 | ||
2822 | /* | |
2823 | * Avoid more than one consumer on a single file descriptor | |
2824 | * This is just a matter of traces coherency, the ring buffer itself | |
2825 | * is protected. | |
2826 | */ | |
2827 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
2828 | if (iter->trace->read) { |
2829 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
2830 | if (sret) | |
2831 | goto out; | |
2832 | } | |
2833 | ||
2834 | waitagain: | |
2835 | sret = tracing_wait_pipe(filp); | |
2836 | if (sret <= 0) | |
2837 | goto out; | |
2838 | ||
b3806b43 | 2839 | /* stop when tracing is finished */ |
ff98781b EGM |
2840 | if (trace_empty(iter)) { |
2841 | sret = 0; | |
107bad8b | 2842 | goto out; |
ff98781b | 2843 | } |
b3806b43 SR |
2844 | |
2845 | if (cnt >= PAGE_SIZE) | |
2846 | cnt = PAGE_SIZE - 1; | |
2847 | ||
53d0aa77 | 2848 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
2849 | memset(&iter->seq, 0, |
2850 | sizeof(struct trace_iterator) - | |
2851 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 2852 | iter->pos = -1; |
b3806b43 | 2853 | |
088b1e42 | 2854 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 2855 | enum print_line_t ret; |
088b1e42 SR |
2856 | int len = iter->seq.len; |
2857 | ||
f9896bf3 | 2858 | ret = print_trace_line(iter); |
2c4f035f | 2859 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
2860 | /* don't print partial lines */ |
2861 | iter->seq.len = len; | |
b3806b43 | 2862 | break; |
088b1e42 | 2863 | } |
b91facc3 FW |
2864 | if (ret != TRACE_TYPE_NO_CONSUME) |
2865 | trace_consume(iter); | |
b3806b43 SR |
2866 | |
2867 | if (iter->seq.len >= cnt) | |
2868 | break; | |
b3806b43 SR |
2869 | } |
2870 | ||
b3806b43 | 2871 | /* Now copy what we have to the user */ |
6c6c2796 PP |
2872 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2873 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 2874 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
2875 | |
2876 | /* | |
2877 | * If there was nothing to send to user, inspite of consuming trace | |
2878 | * entries, go back to wait for more entries. | |
2879 | */ | |
6c6c2796 | 2880 | if (sret == -EBUSY) |
9ff4b974 | 2881 | goto waitagain; |
b3806b43 | 2882 | |
107bad8b | 2883 | out: |
d7350c3f | 2884 | mutex_unlock(&iter->mutex); |
107bad8b | 2885 | |
6c6c2796 | 2886 | return sret; |
b3806b43 SR |
2887 | } |
2888 | ||
3c56819b EGM |
2889 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
2890 | struct pipe_buffer *buf) | |
2891 | { | |
2892 | __free_page(buf->page); | |
2893 | } | |
2894 | ||
2895 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
2896 | unsigned int idx) | |
2897 | { | |
2898 | __free_page(spd->pages[idx]); | |
2899 | } | |
2900 | ||
2901 | static struct pipe_buf_operations tracing_pipe_buf_ops = { | |
34cd4998 SR |
2902 | .can_merge = 0, |
2903 | .map = generic_pipe_buf_map, | |
2904 | .unmap = generic_pipe_buf_unmap, | |
2905 | .confirm = generic_pipe_buf_confirm, | |
2906 | .release = tracing_pipe_buf_release, | |
2907 | .steal = generic_pipe_buf_steal, | |
2908 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
2909 | }; |
2910 | ||
34cd4998 | 2911 | static size_t |
fa7c7f6e | 2912 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
2913 | { |
2914 | size_t count; | |
2915 | int ret; | |
2916 | ||
2917 | /* Seq buffer is page-sized, exactly what we need. */ | |
2918 | for (;;) { | |
2919 | count = iter->seq.len; | |
2920 | ret = print_trace_line(iter); | |
2921 | count = iter->seq.len - count; | |
2922 | if (rem < count) { | |
2923 | rem = 0; | |
2924 | iter->seq.len -= count; | |
2925 | break; | |
2926 | } | |
2927 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
2928 | iter->seq.len -= count; | |
2929 | break; | |
2930 | } | |
2931 | ||
2932 | trace_consume(iter); | |
2933 | rem -= count; | |
2934 | if (!find_next_entry_inc(iter)) { | |
2935 | rem = 0; | |
2936 | iter->ent = NULL; | |
2937 | break; | |
2938 | } | |
2939 | } | |
2940 | ||
2941 | return rem; | |
2942 | } | |
2943 | ||
3c56819b EGM |
2944 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
2945 | loff_t *ppos, | |
2946 | struct pipe_inode_info *pipe, | |
2947 | size_t len, | |
2948 | unsigned int flags) | |
2949 | { | |
2950 | struct page *pages[PIPE_BUFFERS]; | |
2951 | struct partial_page partial[PIPE_BUFFERS]; | |
2952 | struct trace_iterator *iter = filp->private_data; | |
2953 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
2954 | .pages = pages, |
2955 | .partial = partial, | |
2956 | .nr_pages = 0, /* This gets updated below. */ | |
2957 | .flags = flags, | |
2958 | .ops = &tracing_pipe_buf_ops, | |
2959 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 2960 | }; |
d7350c3f | 2961 | static struct tracer *old_tracer; |
3c56819b | 2962 | ssize_t ret; |
34cd4998 | 2963 | size_t rem; |
3c56819b EGM |
2964 | unsigned int i; |
2965 | ||
d7350c3f | 2966 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 2967 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2968 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2969 | old_tracer = current_trace; | |
2970 | *iter->trace = *current_trace; | |
2971 | } | |
2972 | mutex_unlock(&trace_types_lock); | |
2973 | ||
2974 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
2975 | |
2976 | if (iter->trace->splice_read) { | |
2977 | ret = iter->trace->splice_read(iter, filp, | |
2978 | ppos, pipe, len, flags); | |
2979 | if (ret) | |
34cd4998 | 2980 | goto out_err; |
3c56819b EGM |
2981 | } |
2982 | ||
2983 | ret = tracing_wait_pipe(filp); | |
2984 | if (ret <= 0) | |
34cd4998 | 2985 | goto out_err; |
3c56819b EGM |
2986 | |
2987 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
2988 | ret = -EFAULT; | |
34cd4998 | 2989 | goto out_err; |
3c56819b EGM |
2990 | } |
2991 | ||
2992 | /* Fill as many pages as possible. */ | |
2993 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
2994 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
2995 | if (!pages[i]) |
2996 | break; | |
3c56819b | 2997 | |
fa7c7f6e | 2998 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
2999 | |
3000 | /* Copy the data into the page, so we can start over. */ | |
3001 | ret = trace_seq_to_buffer(&iter->seq, | |
3002 | page_address(pages[i]), | |
3003 | iter->seq.len); | |
3004 | if (ret < 0) { | |
3005 | __free_page(pages[i]); | |
3006 | break; | |
3007 | } | |
3008 | partial[i].offset = 0; | |
3009 | partial[i].len = iter->seq.len; | |
3010 | ||
f9520750 | 3011 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3012 | } |
3013 | ||
d7350c3f | 3014 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3015 | |
3016 | spd.nr_pages = i; | |
3017 | ||
3018 | return splice_to_pipe(pipe, &spd); | |
3019 | ||
34cd4998 | 3020 | out_err: |
d7350c3f | 3021 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3022 | |
3023 | return ret; | |
3024 | } | |
3025 | ||
a98a3c3f SR |
3026 | static ssize_t |
3027 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3028 | size_t cnt, loff_t *ppos) | |
3029 | { | |
3030 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3031 | char buf[96]; |
a98a3c3f SR |
3032 | int r; |
3033 | ||
db526ca3 SR |
3034 | mutex_lock(&trace_types_lock); |
3035 | if (!ring_buffer_expanded) | |
3036 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3037 | tr->entries >> 10, | |
3038 | trace_buf_size >> 10); | |
3039 | else | |
3040 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3041 | mutex_unlock(&trace_types_lock); | |
3042 | ||
a98a3c3f SR |
3043 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3044 | } | |
3045 | ||
3046 | static ssize_t | |
3047 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3048 | size_t cnt, loff_t *ppos) | |
3049 | { | |
3050 | unsigned long val; | |
3051 | char buf[64]; | |
bf5e6519 | 3052 | int ret, cpu; |
a98a3c3f | 3053 | |
cffae437 SR |
3054 | if (cnt >= sizeof(buf)) |
3055 | return -EINVAL; | |
a98a3c3f SR |
3056 | |
3057 | if (copy_from_user(&buf, ubuf, cnt)) | |
3058 | return -EFAULT; | |
3059 | ||
3060 | buf[cnt] = 0; | |
3061 | ||
c6caeeb1 SR |
3062 | ret = strict_strtoul(buf, 10, &val); |
3063 | if (ret < 0) | |
3064 | return ret; | |
a98a3c3f SR |
3065 | |
3066 | /* must have at least 1 entry */ | |
3067 | if (!val) | |
3068 | return -EINVAL; | |
3069 | ||
3070 | mutex_lock(&trace_types_lock); | |
3071 | ||
c76f0694 | 3072 | tracing_stop(); |
a98a3c3f | 3073 | |
bf5e6519 SR |
3074 | /* disable all cpu buffers */ |
3075 | for_each_tracing_cpu(cpu) { | |
3076 | if (global_trace.data[cpu]) | |
3077 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3078 | if (max_tr.data[cpu]) | |
3079 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3080 | } | |
3081 | ||
1696b2b0 SR |
3082 | /* value is in KB */ |
3083 | val <<= 10; | |
3084 | ||
3928a8a2 | 3085 | if (val != global_trace.entries) { |
73c5162a | 3086 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3087 | if (ret < 0) { |
3088 | cnt = ret; | |
3eefae99 SR |
3089 | goto out; |
3090 | } | |
a98a3c3f SR |
3091 | } |
3092 | ||
3093 | filp->f_pos += cnt; | |
3094 | ||
19384c03 SR |
3095 | /* If check pages failed, return ENOMEM */ |
3096 | if (tracing_disabled) | |
3097 | cnt = -ENOMEM; | |
a98a3c3f | 3098 | out: |
bf5e6519 SR |
3099 | for_each_tracing_cpu(cpu) { |
3100 | if (global_trace.data[cpu]) | |
3101 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3102 | if (max_tr.data[cpu]) | |
3103 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3104 | } | |
3105 | ||
c76f0694 | 3106 | tracing_start(); |
a98a3c3f SR |
3107 | max_tr.entries = global_trace.entries; |
3108 | mutex_unlock(&trace_types_lock); | |
3109 | ||
3110 | return cnt; | |
3111 | } | |
3112 | ||
5bf9a1ee PP |
3113 | static int mark_printk(const char *fmt, ...) |
3114 | { | |
3115 | int ret; | |
3116 | va_list args; | |
3117 | va_start(args, fmt); | |
1fd8f2a3 | 3118 | ret = trace_vprintk(0, -1, fmt, args); |
5bf9a1ee PP |
3119 | va_end(args); |
3120 | return ret; | |
3121 | } | |
3122 | ||
3123 | static ssize_t | |
3124 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3125 | size_t cnt, loff_t *fpos) | |
3126 | { | |
3127 | char *buf; | |
3128 | char *end; | |
5bf9a1ee | 3129 | |
c76f0694 | 3130 | if (tracing_disabled) |
5bf9a1ee PP |
3131 | return -EINVAL; |
3132 | ||
3133 | if (cnt > TRACE_BUF_SIZE) | |
3134 | cnt = TRACE_BUF_SIZE; | |
3135 | ||
3136 | buf = kmalloc(cnt + 1, GFP_KERNEL); | |
3137 | if (buf == NULL) | |
3138 | return -ENOMEM; | |
3139 | ||
3140 | if (copy_from_user(buf, ubuf, cnt)) { | |
3141 | kfree(buf); | |
3142 | return -EFAULT; | |
3143 | } | |
3144 | ||
3145 | /* Cut from the first nil or newline. */ | |
3146 | buf[cnt] = '\0'; | |
3147 | end = strchr(buf, '\n'); | |
3148 | if (end) | |
3149 | *end = '\0'; | |
3150 | ||
3151 | cnt = mark_printk("%s\n", buf); | |
3152 | kfree(buf); | |
3153 | *fpos += cnt; | |
3154 | ||
3155 | return cnt; | |
3156 | } | |
3157 | ||
5e2336a0 | 3158 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3159 | .open = tracing_open_generic, |
3160 | .read = tracing_max_lat_read, | |
3161 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
3162 | }; |
3163 | ||
5e2336a0 | 3164 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3165 | .open = tracing_open_generic, |
3166 | .read = tracing_ctrl_read, | |
3167 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
3168 | }; |
3169 | ||
5e2336a0 | 3170 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3171 | .open = tracing_open_generic, |
3172 | .read = tracing_set_trace_read, | |
3173 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
3174 | }; |
3175 | ||
5e2336a0 | 3176 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3177 | .open = tracing_open_pipe, |
2a2cc8f7 | 3178 | .poll = tracing_poll_pipe, |
4bf39a94 | 3179 | .read = tracing_read_pipe, |
3c56819b | 3180 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3181 | .release = tracing_release_pipe, |
b3806b43 SR |
3182 | }; |
3183 | ||
5e2336a0 | 3184 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3185 | .open = tracing_open_generic, |
3186 | .read = tracing_entries_read, | |
3187 | .write = tracing_entries_write, | |
3188 | }; | |
3189 | ||
5e2336a0 | 3190 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3191 | .open = tracing_open_generic, |
5bf9a1ee PP |
3192 | .write = tracing_mark_write, |
3193 | }; | |
3194 | ||
2cadf913 SR |
3195 | struct ftrace_buffer_info { |
3196 | struct trace_array *tr; | |
3197 | void *spare; | |
3198 | int cpu; | |
3199 | unsigned int read; | |
3200 | }; | |
3201 | ||
3202 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3203 | { | |
3204 | int cpu = (int)(long)inode->i_private; | |
3205 | struct ftrace_buffer_info *info; | |
3206 | ||
3207 | if (tracing_disabled) | |
3208 | return -ENODEV; | |
3209 | ||
3210 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3211 | if (!info) | |
3212 | return -ENOMEM; | |
3213 | ||
3214 | info->tr = &global_trace; | |
3215 | info->cpu = cpu; | |
3216 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3217 | /* Force reading ring buffer for first read */ | |
3218 | info->read = (unsigned int)-1; | |
3219 | if (!info->spare) | |
3220 | goto out; | |
3221 | ||
3222 | filp->private_data = info; | |
3223 | ||
3224 | return 0; | |
3225 | ||
3226 | out: | |
3227 | kfree(info); | |
3228 | return -ENOMEM; | |
3229 | } | |
3230 | ||
3231 | static ssize_t | |
3232 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3233 | size_t count, loff_t *ppos) | |
3234 | { | |
3235 | struct ftrace_buffer_info *info = filp->private_data; | |
3236 | unsigned int pos; | |
3237 | ssize_t ret; | |
3238 | size_t size; | |
3239 | ||
2dc5d12b SR |
3240 | if (!count) |
3241 | return 0; | |
3242 | ||
2cadf913 SR |
3243 | /* Do we have previous read data to read? */ |
3244 | if (info->read < PAGE_SIZE) | |
3245 | goto read; | |
3246 | ||
3247 | info->read = 0; | |
3248 | ||
3249 | ret = ring_buffer_read_page(info->tr->buffer, | |
3250 | &info->spare, | |
3251 | count, | |
3252 | info->cpu, 0); | |
3253 | if (ret < 0) | |
3254 | return 0; | |
3255 | ||
3256 | pos = ring_buffer_page_len(info->spare); | |
3257 | ||
3258 | if (pos < PAGE_SIZE) | |
3259 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3260 | ||
3261 | read: | |
3262 | size = PAGE_SIZE - info->read; | |
3263 | if (size > count) | |
3264 | size = count; | |
3265 | ||
3266 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3267 | if (ret == size) |
2cadf913 | 3268 | return -EFAULT; |
2dc5d12b SR |
3269 | size -= ret; |
3270 | ||
2cadf913 SR |
3271 | *ppos += size; |
3272 | info->read += size; | |
3273 | ||
3274 | return size; | |
3275 | } | |
3276 | ||
3277 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3278 | { | |
3279 | struct ftrace_buffer_info *info = file->private_data; | |
3280 | ||
3281 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
3282 | kfree(info); | |
3283 | ||
3284 | return 0; | |
3285 | } | |
3286 | ||
3287 | struct buffer_ref { | |
3288 | struct ring_buffer *buffer; | |
3289 | void *page; | |
3290 | int ref; | |
3291 | }; | |
3292 | ||
3293 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3294 | struct pipe_buffer *buf) | |
3295 | { | |
3296 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3297 | ||
3298 | if (--ref->ref) | |
3299 | return; | |
3300 | ||
3301 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3302 | kfree(ref); | |
3303 | buf->private = 0; | |
3304 | } | |
3305 | ||
3306 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3307 | struct pipe_buffer *buf) | |
3308 | { | |
3309 | return 1; | |
3310 | } | |
3311 | ||
3312 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3313 | struct pipe_buffer *buf) | |
3314 | { | |
3315 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3316 | ||
3317 | ref->ref++; | |
3318 | } | |
3319 | ||
3320 | /* Pipe buffer operations for a buffer. */ | |
3321 | static struct pipe_buf_operations buffer_pipe_buf_ops = { | |
3322 | .can_merge = 0, | |
3323 | .map = generic_pipe_buf_map, | |
3324 | .unmap = generic_pipe_buf_unmap, | |
3325 | .confirm = generic_pipe_buf_confirm, | |
3326 | .release = buffer_pipe_buf_release, | |
3327 | .steal = buffer_pipe_buf_steal, | |
3328 | .get = buffer_pipe_buf_get, | |
3329 | }; | |
3330 | ||
3331 | /* | |
3332 | * Callback from splice_to_pipe(), if we need to release some pages | |
3333 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3334 | */ | |
3335 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3336 | { | |
3337 | struct buffer_ref *ref = | |
3338 | (struct buffer_ref *)spd->partial[i].private; | |
3339 | ||
3340 | if (--ref->ref) | |
3341 | return; | |
3342 | ||
3343 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3344 | kfree(ref); | |
3345 | spd->partial[i].private = 0; | |
3346 | } | |
3347 | ||
3348 | static ssize_t | |
3349 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3350 | struct pipe_inode_info *pipe, size_t len, | |
3351 | unsigned int flags) | |
3352 | { | |
3353 | struct ftrace_buffer_info *info = file->private_data; | |
3354 | struct partial_page partial[PIPE_BUFFERS]; | |
3355 | struct page *pages[PIPE_BUFFERS]; | |
3356 | struct splice_pipe_desc spd = { | |
3357 | .pages = pages, | |
3358 | .partial = partial, | |
3359 | .flags = flags, | |
3360 | .ops = &buffer_pipe_buf_ops, | |
3361 | .spd_release = buffer_spd_release, | |
3362 | }; | |
3363 | struct buffer_ref *ref; | |
3364 | int size, i; | |
3365 | size_t ret; | |
3366 | ||
3367 | /* | |
3368 | * We can't seek on a buffer input | |
3369 | */ | |
3370 | if (unlikely(*ppos)) | |
3371 | return -ESPIPE; | |
3372 | ||
3373 | ||
3374 | for (i = 0; i < PIPE_BUFFERS && len; i++, len -= size) { | |
3375 | struct page *page; | |
3376 | int r; | |
3377 | ||
3378 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3379 | if (!ref) | |
3380 | break; | |
3381 | ||
3382 | ref->buffer = info->tr->buffer; | |
3383 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3384 | if (!ref->page) { | |
3385 | kfree(ref); | |
3386 | break; | |
3387 | } | |
3388 | ||
3389 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
3390 | len, info->cpu, 0); | |
3391 | if (r < 0) { | |
3392 | ring_buffer_free_read_page(ref->buffer, | |
3393 | ref->page); | |
3394 | kfree(ref); | |
3395 | break; | |
3396 | } | |
3397 | ||
3398 | /* | |
3399 | * zero out any left over data, this is going to | |
3400 | * user land. | |
3401 | */ | |
3402 | size = ring_buffer_page_len(ref->page); | |
3403 | if (size < PAGE_SIZE) | |
3404 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3405 | ||
3406 | page = virt_to_page(ref->page); | |
3407 | ||
3408 | spd.pages[i] = page; | |
3409 | spd.partial[i].len = PAGE_SIZE; | |
3410 | spd.partial[i].offset = 0; | |
3411 | spd.partial[i].private = (unsigned long)ref; | |
3412 | spd.nr_pages++; | |
3413 | } | |
3414 | ||
3415 | spd.nr_pages = i; | |
3416 | ||
3417 | /* did we read anything? */ | |
3418 | if (!spd.nr_pages) { | |
3419 | if (flags & SPLICE_F_NONBLOCK) | |
3420 | ret = -EAGAIN; | |
3421 | else | |
3422 | ret = 0; | |
3423 | /* TODO: block */ | |
3424 | return ret; | |
3425 | } | |
3426 | ||
3427 | ret = splice_to_pipe(pipe, &spd); | |
3428 | ||
3429 | return ret; | |
3430 | } | |
3431 | ||
3432 | static const struct file_operations tracing_buffers_fops = { | |
3433 | .open = tracing_buffers_open, | |
3434 | .read = tracing_buffers_read, | |
3435 | .release = tracing_buffers_release, | |
3436 | .splice_read = tracing_buffers_splice_read, | |
3437 | .llseek = no_llseek, | |
3438 | }; | |
3439 | ||
bc0c38d1 SR |
3440 | #ifdef CONFIG_DYNAMIC_FTRACE |
3441 | ||
b807c3d0 SR |
3442 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3443 | { | |
3444 | return 0; | |
3445 | } | |
3446 | ||
bc0c38d1 | 3447 | static ssize_t |
b807c3d0 | 3448 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3449 | size_t cnt, loff_t *ppos) |
3450 | { | |
a26a2a27 SR |
3451 | static char ftrace_dyn_info_buffer[1024]; |
3452 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3453 | unsigned long *p = filp->private_data; |
b807c3d0 | 3454 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3455 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3456 | int r; |
3457 | ||
b807c3d0 SR |
3458 | mutex_lock(&dyn_info_mutex); |
3459 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3460 | |
a26a2a27 | 3461 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3462 | buf[r++] = '\n'; |
3463 | ||
3464 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3465 | ||
3466 | mutex_unlock(&dyn_info_mutex); | |
3467 | ||
3468 | return r; | |
bc0c38d1 SR |
3469 | } |
3470 | ||
5e2336a0 | 3471 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3472 | .open = tracing_open_generic, |
b807c3d0 | 3473 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3474 | }; |
3475 | #endif | |
3476 | ||
3477 | static struct dentry *d_tracer; | |
3478 | ||
3479 | struct dentry *tracing_init_dentry(void) | |
3480 | { | |
3481 | static int once; | |
3482 | ||
3483 | if (d_tracer) | |
3484 | return d_tracer; | |
3485 | ||
3486 | d_tracer = debugfs_create_dir("tracing", NULL); | |
3487 | ||
3488 | if (!d_tracer && !once) { | |
3489 | once = 1; | |
3490 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3491 | return NULL; | |
3492 | } | |
3493 | ||
3494 | return d_tracer; | |
3495 | } | |
3496 | ||
b04cc6b1 FW |
3497 | static struct dentry *d_percpu; |
3498 | ||
3499 | struct dentry *tracing_dentry_percpu(void) | |
3500 | { | |
3501 | static int once; | |
3502 | struct dentry *d_tracer; | |
3503 | ||
3504 | if (d_percpu) | |
3505 | return d_percpu; | |
3506 | ||
3507 | d_tracer = tracing_init_dentry(); | |
3508 | ||
3509 | if (!d_tracer) | |
3510 | return NULL; | |
3511 | ||
3512 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
3513 | ||
3514 | if (!d_percpu && !once) { | |
3515 | once = 1; | |
3516 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
3517 | return NULL; | |
3518 | } | |
3519 | ||
3520 | return d_percpu; | |
3521 | } | |
3522 | ||
3523 | static void tracing_init_debugfs_percpu(long cpu) | |
3524 | { | |
3525 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
8656e7a2 FW |
3526 | struct dentry *entry, *d_cpu; |
3527 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ | |
3528 | char cpu_dir[7]; | |
b04cc6b1 FW |
3529 | |
3530 | if (cpu > 999 || cpu < 0) | |
3531 | return; | |
3532 | ||
8656e7a2 FW |
3533 | sprintf(cpu_dir, "cpu%ld", cpu); |
3534 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
3535 | if (!d_cpu) { | |
3536 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
3537 | return; | |
3538 | } | |
b04cc6b1 | 3539 | |
8656e7a2 FW |
3540 | /* per cpu trace_pipe */ |
3541 | entry = debugfs_create_file("trace_pipe", 0444, d_cpu, | |
b04cc6b1 FW |
3542 | (void *) cpu, &tracing_pipe_fops); |
3543 | if (!entry) | |
8656e7a2 | 3544 | pr_warning("Could not create debugfs 'trace_pipe' entry\n"); |
b04cc6b1 FW |
3545 | |
3546 | /* per cpu trace */ | |
8656e7a2 | 3547 | entry = debugfs_create_file("trace", 0444, d_cpu, |
b04cc6b1 FW |
3548 | (void *) cpu, &tracing_fops); |
3549 | if (!entry) | |
8656e7a2 | 3550 | pr_warning("Could not create debugfs 'trace' entry\n"); |
7f96f93f SR |
3551 | |
3552 | entry = debugfs_create_file("trace_pipe_raw", 0444, d_cpu, | |
3553 | (void *) cpu, &tracing_buffers_fops); | |
3554 | if (!entry) | |
3555 | pr_warning("Could not create debugfs 'trace_pipe_raw' entry\n"); | |
b04cc6b1 FW |
3556 | } |
3557 | ||
60a11774 SR |
3558 | #ifdef CONFIG_FTRACE_SELFTEST |
3559 | /* Let selftest have access to static functions in this file */ | |
3560 | #include "trace_selftest.c" | |
3561 | #endif | |
3562 | ||
577b785f SR |
3563 | struct trace_option_dentry { |
3564 | struct tracer_opt *opt; | |
3565 | struct tracer_flags *flags; | |
3566 | struct dentry *entry; | |
3567 | }; | |
3568 | ||
3569 | static ssize_t | |
3570 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3571 | loff_t *ppos) | |
3572 | { | |
3573 | struct trace_option_dentry *topt = filp->private_data; | |
3574 | char *buf; | |
3575 | ||
3576 | if (topt->flags->val & topt->opt->bit) | |
3577 | buf = "1\n"; | |
3578 | else | |
3579 | buf = "0\n"; | |
3580 | ||
3581 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3582 | } | |
3583 | ||
3584 | static ssize_t | |
3585 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3586 | loff_t *ppos) | |
3587 | { | |
3588 | struct trace_option_dentry *topt = filp->private_data; | |
3589 | unsigned long val; | |
3590 | char buf[64]; | |
3591 | int ret; | |
3592 | ||
3593 | if (cnt >= sizeof(buf)) | |
3594 | return -EINVAL; | |
3595 | ||
3596 | if (copy_from_user(&buf, ubuf, cnt)) | |
3597 | return -EFAULT; | |
3598 | ||
3599 | buf[cnt] = 0; | |
3600 | ||
3601 | ret = strict_strtoul(buf, 10, &val); | |
3602 | if (ret < 0) | |
3603 | return ret; | |
3604 | ||
3605 | ret = 0; | |
3606 | switch (val) { | |
3607 | case 0: | |
3608 | /* do nothing if already cleared */ | |
3609 | if (!(topt->flags->val & topt->opt->bit)) | |
3610 | break; | |
3611 | ||
3612 | mutex_lock(&trace_types_lock); | |
3613 | if (current_trace->set_flag) | |
3614 | ret = current_trace->set_flag(topt->flags->val, | |
3615 | topt->opt->bit, 0); | |
3616 | mutex_unlock(&trace_types_lock); | |
3617 | if (ret) | |
3618 | return ret; | |
3619 | topt->flags->val &= ~topt->opt->bit; | |
3620 | break; | |
3621 | case 1: | |
3622 | /* do nothing if already set */ | |
3623 | if (topt->flags->val & topt->opt->bit) | |
3624 | break; | |
3625 | ||
3626 | mutex_lock(&trace_types_lock); | |
3627 | if (current_trace->set_flag) | |
3628 | ret = current_trace->set_flag(topt->flags->val, | |
3629 | topt->opt->bit, 1); | |
3630 | mutex_unlock(&trace_types_lock); | |
3631 | if (ret) | |
3632 | return ret; | |
3633 | topt->flags->val |= topt->opt->bit; | |
3634 | break; | |
3635 | ||
3636 | default: | |
3637 | return -EINVAL; | |
3638 | } | |
3639 | ||
3640 | *ppos += cnt; | |
3641 | ||
3642 | return cnt; | |
3643 | } | |
3644 | ||
3645 | ||
3646 | static const struct file_operations trace_options_fops = { | |
3647 | .open = tracing_open_generic, | |
3648 | .read = trace_options_read, | |
3649 | .write = trace_options_write, | |
3650 | }; | |
3651 | ||
a8259075 SR |
3652 | static ssize_t |
3653 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3654 | loff_t *ppos) | |
3655 | { | |
3656 | long index = (long)filp->private_data; | |
3657 | char *buf; | |
3658 | ||
3659 | if (trace_flags & (1 << index)) | |
3660 | buf = "1\n"; | |
3661 | else | |
3662 | buf = "0\n"; | |
3663 | ||
3664 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3665 | } | |
3666 | ||
3667 | static ssize_t | |
3668 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3669 | loff_t *ppos) | |
3670 | { | |
3671 | long index = (long)filp->private_data; | |
3672 | char buf[64]; | |
3673 | unsigned long val; | |
3674 | int ret; | |
3675 | ||
3676 | if (cnt >= sizeof(buf)) | |
3677 | return -EINVAL; | |
3678 | ||
3679 | if (copy_from_user(&buf, ubuf, cnt)) | |
3680 | return -EFAULT; | |
3681 | ||
3682 | buf[cnt] = 0; | |
3683 | ||
3684 | ret = strict_strtoul(buf, 10, &val); | |
3685 | if (ret < 0) | |
3686 | return ret; | |
3687 | ||
3688 | switch (val) { | |
3689 | case 0: | |
3690 | trace_flags &= ~(1 << index); | |
3691 | break; | |
3692 | case 1: | |
3693 | trace_flags |= 1 << index; | |
3694 | break; | |
3695 | ||
3696 | default: | |
3697 | return -EINVAL; | |
3698 | } | |
3699 | ||
3700 | *ppos += cnt; | |
3701 | ||
3702 | return cnt; | |
3703 | } | |
3704 | ||
a8259075 SR |
3705 | static const struct file_operations trace_options_core_fops = { |
3706 | .open = tracing_open_generic, | |
3707 | .read = trace_options_core_read, | |
3708 | .write = trace_options_core_write, | |
3709 | }; | |
3710 | ||
3711 | static struct dentry *trace_options_init_dentry(void) | |
3712 | { | |
3713 | struct dentry *d_tracer; | |
3714 | static struct dentry *t_options; | |
3715 | ||
3716 | if (t_options) | |
3717 | return t_options; | |
3718 | ||
3719 | d_tracer = tracing_init_dentry(); | |
3720 | if (!d_tracer) | |
3721 | return NULL; | |
3722 | ||
3723 | t_options = debugfs_create_dir("options", d_tracer); | |
3724 | if (!t_options) { | |
3725 | pr_warning("Could not create debugfs directory 'options'\n"); | |
3726 | return NULL; | |
3727 | } | |
3728 | ||
3729 | return t_options; | |
3730 | } | |
3731 | ||
577b785f SR |
3732 | static void |
3733 | create_trace_option_file(struct trace_option_dentry *topt, | |
3734 | struct tracer_flags *flags, | |
3735 | struct tracer_opt *opt) | |
3736 | { | |
3737 | struct dentry *t_options; | |
3738 | struct dentry *entry; | |
3739 | ||
3740 | t_options = trace_options_init_dentry(); | |
3741 | if (!t_options) | |
3742 | return; | |
3743 | ||
3744 | topt->flags = flags; | |
3745 | topt->opt = opt; | |
3746 | ||
3747 | entry = debugfs_create_file(opt->name, 0644, t_options, topt, | |
3748 | &trace_options_fops); | |
3749 | ||
3750 | topt->entry = entry; | |
3751 | ||
3752 | } | |
3753 | ||
3754 | static struct trace_option_dentry * | |
3755 | create_trace_option_files(struct tracer *tracer) | |
3756 | { | |
3757 | struct trace_option_dentry *topts; | |
3758 | struct tracer_flags *flags; | |
3759 | struct tracer_opt *opts; | |
3760 | int cnt; | |
3761 | ||
3762 | if (!tracer) | |
3763 | return NULL; | |
3764 | ||
3765 | flags = tracer->flags; | |
3766 | ||
3767 | if (!flags || !flags->opts) | |
3768 | return NULL; | |
3769 | ||
3770 | opts = flags->opts; | |
3771 | ||
3772 | for (cnt = 0; opts[cnt].name; cnt++) | |
3773 | ; | |
3774 | ||
0cfe8245 | 3775 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
3776 | if (!topts) |
3777 | return NULL; | |
3778 | ||
3779 | for (cnt = 0; opts[cnt].name; cnt++) | |
3780 | create_trace_option_file(&topts[cnt], flags, | |
3781 | &opts[cnt]); | |
3782 | ||
3783 | return topts; | |
3784 | } | |
3785 | ||
3786 | static void | |
3787 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
3788 | { | |
3789 | int cnt; | |
3790 | ||
3791 | if (!topts) | |
3792 | return; | |
3793 | ||
3794 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
3795 | if (topts[cnt].entry) | |
3796 | debugfs_remove(topts[cnt].entry); | |
3797 | } | |
3798 | ||
3799 | kfree(topts); | |
3800 | } | |
3801 | ||
a8259075 SR |
3802 | static struct dentry * |
3803 | create_trace_option_core_file(const char *option, long index) | |
3804 | { | |
3805 | struct dentry *t_options; | |
3806 | struct dentry *entry; | |
3807 | ||
3808 | t_options = trace_options_init_dentry(); | |
3809 | if (!t_options) | |
3810 | return NULL; | |
3811 | ||
3812 | entry = debugfs_create_file(option, 0644, t_options, (void *)index, | |
3813 | &trace_options_core_fops); | |
3814 | ||
3815 | return entry; | |
3816 | } | |
3817 | ||
3818 | static __init void create_trace_options_dir(void) | |
3819 | { | |
3820 | struct dentry *t_options; | |
3821 | struct dentry *entry; | |
3822 | int i; | |
3823 | ||
3824 | t_options = trace_options_init_dentry(); | |
3825 | if (!t_options) | |
3826 | return; | |
3827 | ||
3828 | for (i = 0; trace_options[i]; i++) { | |
3829 | entry = create_trace_option_core_file(trace_options[i], i); | |
3830 | if (!entry) | |
3831 | pr_warning("Could not create debugfs %s entry\n", | |
3832 | trace_options[i]); | |
3833 | } | |
3834 | } | |
3835 | ||
b5ad384e | 3836 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
3837 | { |
3838 | struct dentry *d_tracer; | |
3839 | struct dentry *entry; | |
b04cc6b1 | 3840 | int cpu; |
bc0c38d1 SR |
3841 | |
3842 | d_tracer = tracing_init_dentry(); | |
3843 | ||
3844 | entry = debugfs_create_file("tracing_enabled", 0644, d_tracer, | |
3845 | &global_trace, &tracing_ctrl_fops); | |
3846 | if (!entry) | |
3847 | pr_warning("Could not create debugfs 'tracing_enabled' entry\n"); | |
3848 | ||
ee6bce52 | 3849 | entry = debugfs_create_file("trace_options", 0644, d_tracer, |
bc0c38d1 SR |
3850 | NULL, &tracing_iter_fops); |
3851 | if (!entry) | |
ee6bce52 | 3852 | pr_warning("Could not create debugfs 'trace_options' entry\n"); |
bc0c38d1 | 3853 | |
a8259075 SR |
3854 | create_trace_options_dir(); |
3855 | ||
c7078de1 IM |
3856 | entry = debugfs_create_file("tracing_cpumask", 0644, d_tracer, |
3857 | NULL, &tracing_cpumask_fops); | |
3858 | if (!entry) | |
3859 | pr_warning("Could not create debugfs 'tracing_cpumask' entry\n"); | |
3860 | ||
bc0c38d1 | 3861 | entry = debugfs_create_file("trace", 0444, d_tracer, |
b04cc6b1 | 3862 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); |
bc0c38d1 SR |
3863 | if (!entry) |
3864 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
3865 | ||
3866 | entry = debugfs_create_file("available_tracers", 0444, d_tracer, | |
3867 | &global_trace, &show_traces_fops); | |
3868 | if (!entry) | |
98a983aa | 3869 | pr_warning("Could not create debugfs 'available_tracers' entry\n"); |
bc0c38d1 SR |
3870 | |
3871 | entry = debugfs_create_file("current_tracer", 0444, d_tracer, | |
3872 | &global_trace, &set_tracer_fops); | |
3873 | if (!entry) | |
98a983aa | 3874 | pr_warning("Could not create debugfs 'current_tracer' entry\n"); |
bc0c38d1 SR |
3875 | |
3876 | entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer, | |
3877 | &tracing_max_latency, | |
3878 | &tracing_max_lat_fops); | |
3879 | if (!entry) | |
3880 | pr_warning("Could not create debugfs " | |
3881 | "'tracing_max_latency' entry\n"); | |
3882 | ||
3883 | entry = debugfs_create_file("tracing_thresh", 0644, d_tracer, | |
3884 | &tracing_thresh, &tracing_max_lat_fops); | |
3885 | if (!entry) | |
3886 | pr_warning("Could not create debugfs " | |
98a983aa | 3887 | "'tracing_thresh' entry\n"); |
7bd2f24c IM |
3888 | entry = debugfs_create_file("README", 0644, d_tracer, |
3889 | NULL, &tracing_readme_fops); | |
3890 | if (!entry) | |
3891 | pr_warning("Could not create debugfs 'README' entry\n"); | |
3892 | ||
b04cc6b1 FW |
3893 | entry = debugfs_create_file("trace_pipe", 0444, d_tracer, |
3894 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); | |
b3806b43 SR |
3895 | if (!entry) |
3896 | pr_warning("Could not create debugfs " | |
98a983aa | 3897 | "'trace_pipe' entry\n"); |
bc0c38d1 | 3898 | |
a94c80e7 | 3899 | entry = debugfs_create_file("buffer_size_kb", 0644, d_tracer, |
a98a3c3f SR |
3900 | &global_trace, &tracing_entries_fops); |
3901 | if (!entry) | |
3902 | pr_warning("Could not create debugfs " | |
a94c80e7 | 3903 | "'buffer_size_kb' entry\n"); |
a98a3c3f | 3904 | |
5bf9a1ee PP |
3905 | entry = debugfs_create_file("trace_marker", 0220, d_tracer, |
3906 | NULL, &tracing_mark_fops); | |
3907 | if (!entry) | |
3908 | pr_warning("Could not create debugfs " | |
3909 | "'trace_marker' entry\n"); | |
3910 | ||
bc0c38d1 SR |
3911 | #ifdef CONFIG_DYNAMIC_FTRACE |
3912 | entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer, | |
3913 | &ftrace_update_tot_cnt, | |
b807c3d0 | 3914 | &tracing_dyn_info_fops); |
bc0c38d1 SR |
3915 | if (!entry) |
3916 | pr_warning("Could not create debugfs " | |
3917 | "'dyn_ftrace_total_info' entry\n"); | |
3918 | #endif | |
d618b3e6 IM |
3919 | #ifdef CONFIG_SYSPROF_TRACER |
3920 | init_tracer_sysprof_debugfs(d_tracer); | |
3921 | #endif | |
b04cc6b1 FW |
3922 | |
3923 | for_each_tracing_cpu(cpu) | |
3924 | tracing_init_debugfs_percpu(cpu); | |
3925 | ||
b5ad384e | 3926 | return 0; |
bc0c38d1 SR |
3927 | } |
3928 | ||
3f5a54e3 SR |
3929 | static int trace_panic_handler(struct notifier_block *this, |
3930 | unsigned long event, void *unused) | |
3931 | { | |
944ac425 SR |
3932 | if (ftrace_dump_on_oops) |
3933 | ftrace_dump(); | |
3f5a54e3 SR |
3934 | return NOTIFY_OK; |
3935 | } | |
3936 | ||
3937 | static struct notifier_block trace_panic_notifier = { | |
3938 | .notifier_call = trace_panic_handler, | |
3939 | .next = NULL, | |
3940 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
3941 | }; | |
3942 | ||
3943 | static int trace_die_handler(struct notifier_block *self, | |
3944 | unsigned long val, | |
3945 | void *data) | |
3946 | { | |
3947 | switch (val) { | |
3948 | case DIE_OOPS: | |
944ac425 SR |
3949 | if (ftrace_dump_on_oops) |
3950 | ftrace_dump(); | |
3f5a54e3 SR |
3951 | break; |
3952 | default: | |
3953 | break; | |
3954 | } | |
3955 | return NOTIFY_OK; | |
3956 | } | |
3957 | ||
3958 | static struct notifier_block trace_die_notifier = { | |
3959 | .notifier_call = trace_die_handler, | |
3960 | .priority = 200 | |
3961 | }; | |
3962 | ||
3963 | /* | |
3964 | * printk is set to max of 1024, we really don't need it that big. | |
3965 | * Nothing should be printing 1000 characters anyway. | |
3966 | */ | |
3967 | #define TRACE_MAX_PRINT 1000 | |
3968 | ||
3969 | /* | |
3970 | * Define here KERN_TRACE so that we have one place to modify | |
3971 | * it if we decide to change what log level the ftrace dump | |
3972 | * should be at. | |
3973 | */ | |
428aee14 | 3974 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
3975 | |
3976 | static void | |
3977 | trace_printk_seq(struct trace_seq *s) | |
3978 | { | |
3979 | /* Probably should print a warning here. */ | |
3980 | if (s->len >= 1000) | |
3981 | s->len = 1000; | |
3982 | ||
3983 | /* should be zero ended, but we are paranoid. */ | |
3984 | s->buffer[s->len] = 0; | |
3985 | ||
3986 | printk(KERN_TRACE "%s", s->buffer); | |
3987 | ||
f9520750 | 3988 | trace_seq_init(s); |
3f5a54e3 SR |
3989 | } |
3990 | ||
3f5a54e3 SR |
3991 | void ftrace_dump(void) |
3992 | { | |
3993 | static DEFINE_SPINLOCK(ftrace_dump_lock); | |
3994 | /* use static because iter can be a bit big for the stack */ | |
3995 | static struct trace_iterator iter; | |
3f5a54e3 | 3996 | static int dump_ran; |
d769041f SR |
3997 | unsigned long flags; |
3998 | int cnt = 0, cpu; | |
3f5a54e3 SR |
3999 | |
4000 | /* only one dump */ | |
4001 | spin_lock_irqsave(&ftrace_dump_lock, flags); | |
4002 | if (dump_ran) | |
4003 | goto out; | |
4004 | ||
4005 | dump_ran = 1; | |
4006 | ||
4007 | /* No turning back! */ | |
0ee6b6cf | 4008 | tracing_off(); |
81adbdc0 | 4009 | ftrace_kill(); |
3f5a54e3 | 4010 | |
d769041f SR |
4011 | for_each_tracing_cpu(cpu) { |
4012 | atomic_inc(&global_trace.data[cpu]->disabled); | |
4013 | } | |
4014 | ||
b54d3de9 TE |
4015 | /* don't look at user memory in panic mode */ |
4016 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4017 | ||
3f5a54e3 SR |
4018 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
4019 | ||
e543ad76 | 4020 | /* Simulate the iterator */ |
3f5a54e3 SR |
4021 | iter.tr = &global_trace; |
4022 | iter.trace = current_trace; | |
e543ad76 | 4023 | iter.cpu_file = TRACE_PIPE_ALL_CPU; |
3f5a54e3 SR |
4024 | |
4025 | /* | |
4026 | * We need to stop all tracing on all CPUS to read the | |
4027 | * the next buffer. This is a bit expensive, but is | |
4028 | * not done often. We fill all what we can read, | |
4029 | * and then release the locks again. | |
4030 | */ | |
4031 | ||
3f5a54e3 SR |
4032 | while (!trace_empty(&iter)) { |
4033 | ||
4034 | if (!cnt) | |
4035 | printk(KERN_TRACE "---------------------------------\n"); | |
4036 | ||
4037 | cnt++; | |
4038 | ||
4039 | /* reset all but tr, trace, and overruns */ | |
4040 | memset(&iter.seq, 0, | |
4041 | sizeof(struct trace_iterator) - | |
4042 | offsetof(struct trace_iterator, seq)); | |
4043 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4044 | iter.pos = -1; | |
4045 | ||
4046 | if (find_next_entry_inc(&iter) != NULL) { | |
4047 | print_trace_line(&iter); | |
4048 | trace_consume(&iter); | |
4049 | } | |
4050 | ||
4051 | trace_printk_seq(&iter.seq); | |
4052 | } | |
4053 | ||
4054 | if (!cnt) | |
4055 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4056 | else | |
4057 | printk(KERN_TRACE "---------------------------------\n"); | |
4058 | ||
3f5a54e3 SR |
4059 | out: |
4060 | spin_unlock_irqrestore(&ftrace_dump_lock, flags); | |
4061 | } | |
4062 | ||
3928a8a2 | 4063 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4064 | { |
4c11d7ae | 4065 | struct trace_array_cpu *data; |
73c5162a | 4066 | int ring_buf_size; |
4c11d7ae | 4067 | int i; |
9e01c1b7 | 4068 | int ret = -ENOMEM; |
4c11d7ae | 4069 | |
9e01c1b7 RR |
4070 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4071 | goto out; | |
4072 | ||
4073 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4074 | goto out_free_buffer_mask; | |
4c11d7ae | 4075 | |
b04cc6b1 FW |
4076 | if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) |
4077 | goto out_free_tracing_cpumask; | |
4078 | ||
73c5162a SR |
4079 | /* To save memory, keep the ring buffer size to its minimum */ |
4080 | if (ring_buffer_expanded) | |
4081 | ring_buf_size = trace_buf_size; | |
4082 | else | |
4083 | ring_buf_size = 1; | |
4084 | ||
9e01c1b7 RR |
4085 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4086 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
b04cc6b1 | 4087 | cpumask_clear(tracing_reader_cpumask); |
9e01c1b7 RR |
4088 | |
4089 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
73c5162a | 4090 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4091 | TRACE_BUFFER_FLAGS); |
4092 | if (!global_trace.buffer) { | |
4093 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4094 | WARN_ON(1); | |
9e01c1b7 | 4095 | goto out_free_cpumask; |
4c11d7ae | 4096 | } |
3928a8a2 | 4097 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4098 | |
9e01c1b7 | 4099 | |
4c11d7ae | 4100 | #ifdef CONFIG_TRACER_MAX_TRACE |
73c5162a | 4101 | max_tr.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4102 | TRACE_BUFFER_FLAGS); |
4103 | if (!max_tr.buffer) { | |
4104 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4105 | WARN_ON(1); | |
4106 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4107 | goto out_free_cpumask; |
4c11d7ae | 4108 | } |
3928a8a2 SR |
4109 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
4110 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 4111 | #endif |
ab46428c | 4112 | |
4c11d7ae | 4113 | /* Allocate the first page for all buffers */ |
ab46428c | 4114 | for_each_tracing_cpu(i) { |
4c11d7ae | 4115 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 | 4116 | max_tr.data[i] = &per_cpu(max_data, i); |
4c11d7ae | 4117 | } |
bc0c38d1 | 4118 | |
bc0c38d1 SR |
4119 | trace_init_cmdlines(); |
4120 | ||
43a15386 | 4121 | register_tracer(&nop_trace); |
79fb0768 | 4122 | current_trace = &nop_trace; |
b5ad384e FW |
4123 | #ifdef CONFIG_BOOT_TRACER |
4124 | register_tracer(&boot_tracer); | |
b5ad384e | 4125 | #endif |
60a11774 SR |
4126 | /* All seems OK, enable tracing */ |
4127 | tracing_disabled = 0; | |
3928a8a2 | 4128 | |
3f5a54e3 SR |
4129 | atomic_notifier_chain_register(&panic_notifier_list, |
4130 | &trace_panic_notifier); | |
4131 | ||
4132 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4133 | |
4134 | return 0; | |
3f5a54e3 | 4135 | |
9e01c1b7 | 4136 | out_free_cpumask: |
b04cc6b1 FW |
4137 | free_cpumask_var(tracing_reader_cpumask); |
4138 | out_free_tracing_cpumask: | |
9e01c1b7 RR |
4139 | free_cpumask_var(tracing_cpumask); |
4140 | out_free_buffer_mask: | |
4141 | free_cpumask_var(tracing_buffer_mask); | |
4142 | out: | |
4143 | return ret; | |
bc0c38d1 | 4144 | } |
b2821ae6 SR |
4145 | |
4146 | __init static int clear_boot_tracer(void) | |
4147 | { | |
4148 | /* | |
4149 | * The default tracer at boot buffer is an init section. | |
4150 | * This function is called in lateinit. If we did not | |
4151 | * find the boot tracer, then clear it out, to prevent | |
4152 | * later registration from accessing the buffer that is | |
4153 | * about to be freed. | |
4154 | */ | |
4155 | if (!default_bootup_tracer) | |
4156 | return 0; | |
4157 | ||
4158 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4159 | default_bootup_tracer); | |
4160 | default_bootup_tracer = NULL; | |
4161 | ||
4162 | return 0; | |
4163 | } | |
4164 | ||
b5ad384e FW |
4165 | early_initcall(tracer_alloc_buffers); |
4166 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4167 | late_initcall(clear_boot_tracer); |