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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> | |
405f5571 | 20 | #include <linux/smp_lock.h> |
3f5a54e3 | 21 | #include <linux/notifier.h> |
2cadf913 | 22 | #include <linux/irqflags.h> |
bc0c38d1 | 23 | #include <linux/debugfs.h> |
4c11d7ae | 24 | #include <linux/pagemap.h> |
bc0c38d1 SR |
25 | #include <linux/hardirq.h> |
26 | #include <linux/linkage.h> | |
27 | #include <linux/uaccess.h> | |
2cadf913 | 28 | #include <linux/kprobes.h> |
bc0c38d1 SR |
29 | #include <linux/ftrace.h> |
30 | #include <linux/module.h> | |
31 | #include <linux/percpu.h> | |
2cadf913 | 32 | #include <linux/splice.h> |
3f5a54e3 | 33 | #include <linux/kdebug.h> |
5f0c6c03 | 34 | #include <linux/string.h> |
bc0c38d1 SR |
35 | #include <linux/ctype.h> |
36 | #include <linux/init.h> | |
2a2cc8f7 | 37 | #include <linux/poll.h> |
bc0c38d1 SR |
38 | #include <linux/gfp.h> |
39 | #include <linux/fs.h> | |
86387f7e | 40 | |
bc0c38d1 | 41 | #include "trace.h" |
f0868d1e | 42 | #include "trace_output.h" |
bc0c38d1 | 43 | |
3928a8a2 SR |
44 | #define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE) |
45 | ||
73c5162a SR |
46 | /* |
47 | * On boot up, the ring buffer is set to the minimum size, so that | |
48 | * we do not waste memory on systems that are not using tracing. | |
49 | */ | |
020e5f85 | 50 | int ring_buffer_expanded; |
73c5162a | 51 | |
8e1b82e0 FW |
52 | /* |
53 | * We need to change this state when a selftest is running. | |
ff32504f FW |
54 | * A selftest will lurk into the ring-buffer to count the |
55 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 56 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
57 | * at the same time, giving false positive or negative results. |
58 | */ | |
8e1b82e0 | 59 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 60 | |
b2821ae6 SR |
61 | /* |
62 | * If a tracer is running, we do not want to run SELFTEST. | |
63 | */ | |
020e5f85 | 64 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 65 | |
adf9f195 FW |
66 | /* For tracers that don't implement custom flags */ |
67 | static struct tracer_opt dummy_tracer_opt[] = { | |
68 | { } | |
69 | }; | |
70 | ||
71 | static struct tracer_flags dummy_tracer_flags = { | |
72 | .val = 0, | |
73 | .opts = dummy_tracer_opt | |
74 | }; | |
75 | ||
76 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
77 | { | |
78 | return 0; | |
79 | } | |
0f048701 SR |
80 | |
81 | /* | |
82 | * Kill all tracing for good (never come back). | |
83 | * It is initialized to 1 but will turn to zero if the initialization | |
84 | * of the tracer is successful. But that is the only place that sets | |
85 | * this back to zero. | |
86 | */ | |
4fd27358 | 87 | static int tracing_disabled = 1; |
0f048701 | 88 | |
5e5bf483 | 89 | DEFINE_PER_CPU(local_t, ftrace_cpu_disabled); |
d769041f SR |
90 | |
91 | static inline void ftrace_disable_cpu(void) | |
92 | { | |
93 | preempt_disable(); | |
94 | local_inc(&__get_cpu_var(ftrace_cpu_disabled)); | |
95 | } | |
96 | ||
97 | static inline void ftrace_enable_cpu(void) | |
98 | { | |
99 | local_dec(&__get_cpu_var(ftrace_cpu_disabled)); | |
100 | preempt_enable(); | |
101 | } | |
102 | ||
9e01c1b7 | 103 | static cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 104 | |
b04cc6b1 FW |
105 | /* Define which cpu buffers are currently read in trace_pipe */ |
106 | static cpumask_var_t tracing_reader_cpumask; | |
107 | ||
ab46428c | 108 | #define for_each_tracing_cpu(cpu) \ |
9e01c1b7 | 109 | for_each_cpu(cpu, tracing_buffer_mask) |
ab46428c | 110 | |
944ac425 SR |
111 | /* |
112 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
113 | * | |
114 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
115 | * is set, then ftrace_dump is called. This will output the contents | |
116 | * of the ftrace buffers to the console. This is very useful for | |
117 | * capturing traces that lead to crashes and outputing it to a | |
118 | * serial console. | |
119 | * | |
120 | * It is default off, but you can enable it with either specifying | |
121 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
122 | * /proc/sys/kernel/ftrace_dump_on_oops to true. | |
123 | */ | |
124 | int ftrace_dump_on_oops; | |
125 | ||
b2821ae6 SR |
126 | static int tracing_set_tracer(const char *buf); |
127 | ||
128 | #define BOOTUP_TRACER_SIZE 100 | |
129 | static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata; | |
130 | static char *default_bootup_tracer; | |
d9e54076 PZ |
131 | |
132 | static int __init set_ftrace(char *str) | |
133 | { | |
b2821ae6 SR |
134 | strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); |
135 | default_bootup_tracer = bootup_tracer_buf; | |
73c5162a SR |
136 | /* We are using ftrace early, expand it */ |
137 | ring_buffer_expanded = 1; | |
d9e54076 PZ |
138 | return 1; |
139 | } | |
b2821ae6 | 140 | __setup("ftrace=", set_ftrace); |
d9e54076 | 141 | |
944ac425 SR |
142 | static int __init set_ftrace_dump_on_oops(char *str) |
143 | { | |
144 | ftrace_dump_on_oops = 1; | |
145 | return 1; | |
146 | } | |
147 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 148 | |
cf8e3474 | 149 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
150 | { |
151 | nsec += 500; | |
152 | do_div(nsec, 1000); | |
153 | return nsec; | |
154 | } | |
155 | ||
4fcdae83 SR |
156 | /* |
157 | * The global_trace is the descriptor that holds the tracing | |
158 | * buffers for the live tracing. For each CPU, it contains | |
159 | * a link list of pages that will store trace entries. The | |
160 | * page descriptor of the pages in the memory is used to hold | |
161 | * the link list by linking the lru item in the page descriptor | |
162 | * to each of the pages in the buffer per CPU. | |
163 | * | |
164 | * For each active CPU there is a data field that holds the | |
165 | * pages for the buffer for that CPU. Each CPU has the same number | |
166 | * of pages allocated for its buffer. | |
167 | */ | |
bc0c38d1 SR |
168 | static struct trace_array global_trace; |
169 | ||
170 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
171 | ||
eb02ce01 TZ |
172 | int filter_current_check_discard(struct ftrace_event_call *call, void *rec, |
173 | struct ring_buffer_event *event) | |
174 | { | |
175 | return filter_check_discard(call, rec, global_trace.buffer, event); | |
176 | } | |
17c873ec | 177 | EXPORT_SYMBOL_GPL(filter_current_check_discard); |
eb02ce01 | 178 | |
37886f6a SR |
179 | cycle_t ftrace_now(int cpu) |
180 | { | |
181 | u64 ts; | |
182 | ||
183 | /* Early boot up does not have a buffer yet */ | |
184 | if (!global_trace.buffer) | |
185 | return trace_clock_local(); | |
186 | ||
187 | ts = ring_buffer_time_stamp(global_trace.buffer, cpu); | |
188 | ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts); | |
189 | ||
190 | return ts; | |
191 | } | |
bc0c38d1 | 192 | |
4fcdae83 SR |
193 | /* |
194 | * The max_tr is used to snapshot the global_trace when a maximum | |
195 | * latency is reached. Some tracers will use this to store a maximum | |
196 | * trace while it continues examining live traces. | |
197 | * | |
198 | * The buffers for the max_tr are set up the same as the global_trace. | |
199 | * When a snapshot is taken, the link list of the max_tr is swapped | |
200 | * with the link list of the global_trace and the buffers are reset for | |
201 | * the global_trace so the tracing can continue. | |
202 | */ | |
bc0c38d1 SR |
203 | static struct trace_array max_tr; |
204 | ||
205 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
206 | ||
4fcdae83 | 207 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 208 | static int tracer_enabled = 1; |
4fcdae83 | 209 | |
9036990d SR |
210 | /** |
211 | * tracing_is_enabled - return tracer_enabled status | |
212 | * | |
213 | * This function is used by other tracers to know the status | |
214 | * of the tracer_enabled flag. Tracers may use this function | |
215 | * to know if it should enable their features when starting | |
216 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
217 | */ | |
218 | int tracing_is_enabled(void) | |
219 | { | |
220 | return tracer_enabled; | |
221 | } | |
222 | ||
4fcdae83 | 223 | /* |
3928a8a2 SR |
224 | * trace_buf_size is the size in bytes that is allocated |
225 | * for a buffer. Note, the number of bytes is always rounded | |
226 | * to page size. | |
3f5a54e3 SR |
227 | * |
228 | * This number is purposely set to a low number of 16384. | |
229 | * If the dump on oops happens, it will be much appreciated | |
230 | * to not have to wait for all that output. Anyway this can be | |
231 | * boot time and run time configurable. | |
4fcdae83 | 232 | */ |
3928a8a2 | 233 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 234 | |
3928a8a2 | 235 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 236 | |
4fcdae83 | 237 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 238 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
239 | |
240 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 241 | static struct tracer *current_trace __read_mostly; |
4fcdae83 SR |
242 | |
243 | /* | |
244 | * max_tracer_type_len is used to simplify the allocating of | |
245 | * buffers to read userspace tracer names. We keep track of | |
246 | * the longest tracer name registered. | |
247 | */ | |
bc0c38d1 SR |
248 | static int max_tracer_type_len; |
249 | ||
4fcdae83 SR |
250 | /* |
251 | * trace_types_lock is used to protect the trace_types list. | |
252 | * This lock is also used to keep user access serialized. | |
253 | * Accesses from userspace will grab this lock while userspace | |
254 | * activities happen inside the kernel. | |
255 | */ | |
bc0c38d1 | 256 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
257 | |
258 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
259 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
260 | ||
ee6bce52 | 261 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 262 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
a2a16d6a SR |
263 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | |
264 | TRACE_ITER_GRAPH_TIME; | |
4e655519 | 265 | |
b8de7bd1 SR |
266 | static int trace_stop_count; |
267 | static DEFINE_SPINLOCK(tracing_start_lock); | |
268 | ||
4fcdae83 SR |
269 | /** |
270 | * trace_wake_up - wake up tasks waiting for trace input | |
271 | * | |
272 | * Simply wakes up any task that is blocked on the trace_wait | |
273 | * queue. These is used with trace_poll for tasks polling the trace. | |
274 | */ | |
4e655519 IM |
275 | void trace_wake_up(void) |
276 | { | |
017730c1 IM |
277 | /* |
278 | * The runqueue_is_locked() can fail, but this is the best we | |
279 | * have for now: | |
280 | */ | |
281 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
282 | wake_up(&trace_wait); |
283 | } | |
bc0c38d1 | 284 | |
3928a8a2 | 285 | static int __init set_buf_size(char *str) |
bc0c38d1 | 286 | { |
3928a8a2 | 287 | unsigned long buf_size; |
c6caeeb1 | 288 | |
bc0c38d1 SR |
289 | if (!str) |
290 | return 0; | |
9d612bef | 291 | buf_size = memparse(str, &str); |
c6caeeb1 | 292 | /* nr_entries can not be zero */ |
9d612bef | 293 | if (buf_size == 0) |
c6caeeb1 | 294 | return 0; |
3928a8a2 | 295 | trace_buf_size = buf_size; |
bc0c38d1 SR |
296 | return 1; |
297 | } | |
3928a8a2 | 298 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 299 | |
57f50be1 SR |
300 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
301 | { | |
302 | return nsecs / 1000; | |
303 | } | |
304 | ||
4fcdae83 | 305 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
306 | static const char *trace_options[] = { |
307 | "print-parent", | |
308 | "sym-offset", | |
309 | "sym-addr", | |
310 | "verbose", | |
f9896bf3 | 311 | "raw", |
5e3ca0ec | 312 | "hex", |
cb0f12aa | 313 | "bin", |
2a2cc8f7 | 314 | "block", |
86387f7e | 315 | "stacktrace", |
4ac3ba41 | 316 | "sched-tree", |
5e1607a0 | 317 | "trace_printk", |
b2a866f9 | 318 | "ftrace_preempt", |
9f029e83 | 319 | "branch", |
12ef7d44 | 320 | "annotate", |
02b67518 | 321 | "userstacktrace", |
b54d3de9 | 322 | "sym-userobj", |
66896a85 | 323 | "printk-msg-only", |
c4a8e8be | 324 | "context-info", |
c032ef64 | 325 | "latency-format", |
be6f164a | 326 | "sleep-time", |
a2a16d6a | 327 | "graph-time", |
bc0c38d1 SR |
328 | NULL |
329 | }; | |
330 | ||
5079f326 Z |
331 | static struct { |
332 | u64 (*func)(void); | |
333 | const char *name; | |
334 | } trace_clocks[] = { | |
335 | { trace_clock_local, "local" }, | |
336 | { trace_clock_global, "global" }, | |
337 | }; | |
338 | ||
339 | int trace_clock_id; | |
340 | ||
6c6c2796 PP |
341 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
342 | { | |
343 | int len; | |
344 | int ret; | |
345 | ||
2dc5d12b SR |
346 | if (!cnt) |
347 | return 0; | |
348 | ||
6c6c2796 PP |
349 | if (s->len <= s->readpos) |
350 | return -EBUSY; | |
351 | ||
352 | len = s->len - s->readpos; | |
353 | if (cnt > len) | |
354 | cnt = len; | |
355 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 356 | if (ret == cnt) |
6c6c2796 PP |
357 | return -EFAULT; |
358 | ||
2dc5d12b SR |
359 | cnt -= ret; |
360 | ||
e74da523 | 361 | s->readpos += cnt; |
6c6c2796 | 362 | return cnt; |
214023c3 SR |
363 | } |
364 | ||
b8b94265 | 365 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
366 | { |
367 | int len; | |
368 | void *ret; | |
369 | ||
370 | if (s->len <= s->readpos) | |
371 | return -EBUSY; | |
372 | ||
373 | len = s->len - s->readpos; | |
374 | if (cnt > len) | |
375 | cnt = len; | |
376 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
377 | if (!ret) | |
378 | return -EFAULT; | |
379 | ||
e74da523 | 380 | s->readpos += cnt; |
3c56819b EGM |
381 | return cnt; |
382 | } | |
383 | ||
5d4a9dba SR |
384 | /* |
385 | * ftrace_max_lock is used to protect the swapping of buffers | |
386 | * when taking a max snapshot. The buffers themselves are | |
387 | * protected by per_cpu spinlocks. But the action of the swap | |
388 | * needs its own lock. | |
389 | * | |
390 | * This is defined as a raw_spinlock_t in order to help | |
391 | * with performance when lockdep debugging is enabled. | |
392 | * | |
393 | * It is also used in other places outside the update_max_tr | |
394 | * so it needs to be defined outside of the | |
395 | * CONFIG_TRACER_MAX_TRACE. | |
396 | */ | |
397 | static raw_spinlock_t ftrace_max_lock = | |
398 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
399 | ||
400 | #ifdef CONFIG_TRACER_MAX_TRACE | |
401 | unsigned long __read_mostly tracing_max_latency; | |
402 | unsigned long __read_mostly tracing_thresh; | |
403 | ||
404 | /* | |
405 | * Copy the new maximum trace into the separate maximum-trace | |
406 | * structure. (this way the maximum trace is permanently saved, | |
407 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
408 | */ | |
409 | static void | |
410 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
411 | { | |
412 | struct trace_array_cpu *data = tr->data[cpu]; | |
8248ac05 | 413 | struct trace_array_cpu *max_data = tr->data[cpu]; |
5d4a9dba SR |
414 | |
415 | max_tr.cpu = cpu; | |
416 | max_tr.time_start = data->preempt_timestamp; | |
417 | ||
8248ac05 SR |
418 | max_data = max_tr.data[cpu]; |
419 | max_data->saved_latency = tracing_max_latency; | |
420 | max_data->critical_start = data->critical_start; | |
421 | max_data->critical_end = data->critical_end; | |
5d4a9dba SR |
422 | |
423 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
8248ac05 SR |
424 | max_data->pid = tsk->pid; |
425 | max_data->uid = task_uid(tsk); | |
426 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
427 | max_data->policy = tsk->policy; | |
428 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
429 | |
430 | /* record this tasks comm */ | |
431 | tracing_record_cmdline(tsk); | |
432 | } | |
433 | ||
4fcdae83 SR |
434 | /** |
435 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
436 | * @tr: tracer | |
437 | * @tsk: the task with the latency | |
438 | * @cpu: The cpu that initiated the trace. | |
439 | * | |
440 | * Flip the buffers between the @tr and the max_tr and record information | |
441 | * about which task was the cause of this latency. | |
442 | */ | |
e309b41d | 443 | void |
bc0c38d1 SR |
444 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
445 | { | |
3928a8a2 | 446 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 447 | |
b8de7bd1 SR |
448 | if (trace_stop_count) |
449 | return; | |
450 | ||
4c11d7ae | 451 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 452 | __raw_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
453 | |
454 | tr->buffer = max_tr.buffer; | |
455 | max_tr.buffer = buf; | |
456 | ||
bc0c38d1 | 457 | __update_max_tr(tr, tsk, cpu); |
92205c23 | 458 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
459 | } |
460 | ||
461 | /** | |
462 | * update_max_tr_single - only copy one trace over, and reset the rest | |
463 | * @tr - tracer | |
464 | * @tsk - task with the latency | |
465 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
466 | * |
467 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 468 | */ |
e309b41d | 469 | void |
bc0c38d1 SR |
470 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
471 | { | |
3928a8a2 | 472 | int ret; |
bc0c38d1 | 473 | |
b8de7bd1 SR |
474 | if (trace_stop_count) |
475 | return; | |
476 | ||
4c11d7ae | 477 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 478 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 479 | |
d769041f SR |
480 | ftrace_disable_cpu(); |
481 | ||
3928a8a2 SR |
482 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); |
483 | ||
d769041f SR |
484 | ftrace_enable_cpu(); |
485 | ||
97b17efe | 486 | WARN_ON_ONCE(ret && ret != -EAGAIN); |
bc0c38d1 SR |
487 | |
488 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 489 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 | 490 | } |
5d4a9dba | 491 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 492 | |
4fcdae83 SR |
493 | /** |
494 | * register_tracer - register a tracer with the ftrace system. | |
495 | * @type - the plugin for the tracer | |
496 | * | |
497 | * Register a new plugin tracer. | |
498 | */ | |
bc0c38d1 | 499 | int register_tracer(struct tracer *type) |
e7669b8e HE |
500 | __releases(kernel_lock) |
501 | __acquires(kernel_lock) | |
bc0c38d1 SR |
502 | { |
503 | struct tracer *t; | |
504 | int len; | |
505 | int ret = 0; | |
506 | ||
507 | if (!type->name) { | |
508 | pr_info("Tracer must have a name\n"); | |
509 | return -1; | |
510 | } | |
511 | ||
86fa2f60 IM |
512 | /* |
513 | * When this gets called we hold the BKL which means that | |
514 | * preemption is disabled. Various trace selftests however | |
515 | * need to disable and enable preemption for successful tests. | |
516 | * So we drop the BKL here and grab it after the tests again. | |
517 | */ | |
518 | unlock_kernel(); | |
bc0c38d1 | 519 | mutex_lock(&trace_types_lock); |
86fa2f60 | 520 | |
8e1b82e0 FW |
521 | tracing_selftest_running = true; |
522 | ||
bc0c38d1 SR |
523 | for (t = trace_types; t; t = t->next) { |
524 | if (strcmp(type->name, t->name) == 0) { | |
525 | /* already found */ | |
526 | pr_info("Trace %s already registered\n", | |
527 | type->name); | |
528 | ret = -1; | |
529 | goto out; | |
530 | } | |
531 | } | |
532 | ||
adf9f195 FW |
533 | if (!type->set_flag) |
534 | type->set_flag = &dummy_set_flag; | |
535 | if (!type->flags) | |
536 | type->flags = &dummy_tracer_flags; | |
537 | else | |
538 | if (!type->flags->opts) | |
539 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
540 | if (!type->wait_pipe) |
541 | type->wait_pipe = default_wait_pipe; | |
542 | ||
adf9f195 | 543 | |
60a11774 | 544 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 545 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 546 | struct tracer *saved_tracer = current_trace; |
60a11774 | 547 | struct trace_array *tr = &global_trace; |
ff32504f | 548 | |
60a11774 SR |
549 | /* |
550 | * Run a selftest on this tracer. | |
551 | * Here we reset the trace buffer, and set the current | |
552 | * tracer to be this tracer. The tracer can then run some | |
553 | * internal tracing to verify that everything is in order. | |
554 | * If we fail, we do not register this tracer. | |
555 | */ | |
76f0d073 | 556 | tracing_reset_online_cpus(tr); |
86fa2f60 | 557 | |
60a11774 | 558 | current_trace = type; |
60a11774 SR |
559 | /* the test is responsible for initializing and enabling */ |
560 | pr_info("Testing tracer %s: ", type->name); | |
561 | ret = type->selftest(type, tr); | |
562 | /* the test is responsible for resetting too */ | |
563 | current_trace = saved_tracer; | |
60a11774 SR |
564 | if (ret) { |
565 | printk(KERN_CONT "FAILED!\n"); | |
566 | goto out; | |
567 | } | |
1d4db00a | 568 | /* Only reset on passing, to avoid touching corrupted buffers */ |
76f0d073 | 569 | tracing_reset_online_cpus(tr); |
86fa2f60 | 570 | |
60a11774 SR |
571 | printk(KERN_CONT "PASSED\n"); |
572 | } | |
573 | #endif | |
574 | ||
bc0c38d1 SR |
575 | type->next = trace_types; |
576 | trace_types = type; | |
577 | len = strlen(type->name); | |
578 | if (len > max_tracer_type_len) | |
579 | max_tracer_type_len = len; | |
60a11774 | 580 | |
bc0c38d1 | 581 | out: |
8e1b82e0 | 582 | tracing_selftest_running = false; |
bc0c38d1 SR |
583 | mutex_unlock(&trace_types_lock); |
584 | ||
dac74940 SR |
585 | if (ret || !default_bootup_tracer) |
586 | goto out_unlock; | |
587 | ||
588 | if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE)) | |
589 | goto out_unlock; | |
590 | ||
591 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
592 | /* Do we want this tracer to start on bootup? */ | |
593 | tracing_set_tracer(type->name); | |
594 | default_bootup_tracer = NULL; | |
595 | /* disable other selftests, since this will break it. */ | |
596 | tracing_selftest_disabled = 1; | |
b2821ae6 | 597 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
598 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
599 | type->name); | |
b2821ae6 | 600 | #endif |
b2821ae6 | 601 | |
dac74940 | 602 | out_unlock: |
b2821ae6 | 603 | lock_kernel(); |
bc0c38d1 SR |
604 | return ret; |
605 | } | |
606 | ||
607 | void unregister_tracer(struct tracer *type) | |
608 | { | |
609 | struct tracer **t; | |
610 | int len; | |
611 | ||
612 | mutex_lock(&trace_types_lock); | |
613 | for (t = &trace_types; *t; t = &(*t)->next) { | |
614 | if (*t == type) | |
615 | goto found; | |
616 | } | |
617 | pr_info("Trace %s not registered\n", type->name); | |
618 | goto out; | |
619 | ||
620 | found: | |
621 | *t = (*t)->next; | |
b5db03c4 ACM |
622 | |
623 | if (type == current_trace && tracer_enabled) { | |
624 | tracer_enabled = 0; | |
625 | tracing_stop(); | |
626 | if (current_trace->stop) | |
627 | current_trace->stop(&global_trace); | |
628 | current_trace = &nop_trace; | |
629 | } | |
630 | ||
bc0c38d1 SR |
631 | if (strlen(type->name) != max_tracer_type_len) |
632 | goto out; | |
633 | ||
634 | max_tracer_type_len = 0; | |
635 | for (t = &trace_types; *t; t = &(*t)->next) { | |
636 | len = strlen((*t)->name); | |
637 | if (len > max_tracer_type_len) | |
638 | max_tracer_type_len = len; | |
639 | } | |
640 | out: | |
641 | mutex_unlock(&trace_types_lock); | |
642 | } | |
643 | ||
f633903a | 644 | static void __tracing_reset(struct trace_array *tr, int cpu) |
bc0c38d1 | 645 | { |
d769041f | 646 | ftrace_disable_cpu(); |
3928a8a2 | 647 | ring_buffer_reset_cpu(tr->buffer, cpu); |
d769041f | 648 | ftrace_enable_cpu(); |
bc0c38d1 SR |
649 | } |
650 | ||
f633903a SR |
651 | void tracing_reset(struct trace_array *tr, int cpu) |
652 | { | |
653 | struct ring_buffer *buffer = tr->buffer; | |
654 | ||
655 | ring_buffer_record_disable(buffer); | |
656 | ||
657 | /* Make sure all commits have finished */ | |
658 | synchronize_sched(); | |
659 | __tracing_reset(tr, cpu); | |
660 | ||
661 | ring_buffer_record_enable(buffer); | |
662 | } | |
663 | ||
213cc060 PE |
664 | void tracing_reset_online_cpus(struct trace_array *tr) |
665 | { | |
621968cd | 666 | struct ring_buffer *buffer = tr->buffer; |
213cc060 PE |
667 | int cpu; |
668 | ||
621968cd SR |
669 | ring_buffer_record_disable(buffer); |
670 | ||
671 | /* Make sure all commits have finished */ | |
672 | synchronize_sched(); | |
673 | ||
213cc060 PE |
674 | tr->time_start = ftrace_now(tr->cpu); |
675 | ||
676 | for_each_online_cpu(cpu) | |
f633903a | 677 | __tracing_reset(tr, cpu); |
621968cd SR |
678 | |
679 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
680 | } |
681 | ||
9456f0fa SR |
682 | void tracing_reset_current(int cpu) |
683 | { | |
684 | tracing_reset(&global_trace, cpu); | |
685 | } | |
686 | ||
687 | void tracing_reset_current_online_cpus(void) | |
688 | { | |
689 | tracing_reset_online_cpus(&global_trace); | |
690 | } | |
691 | ||
bc0c38d1 | 692 | #define SAVED_CMDLINES 128 |
2c7eea4c | 693 | #define NO_CMDLINE_MAP UINT_MAX |
bc0c38d1 SR |
694 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; |
695 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
696 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
697 | static int cmdline_idx; | |
efed792d | 698 | static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; |
25b0b44a | 699 | |
25b0b44a | 700 | /* temporary disable recording */ |
4fd27358 | 701 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
702 | |
703 | static void trace_init_cmdlines(void) | |
704 | { | |
2c7eea4c TG |
705 | memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline)); |
706 | memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid)); | |
bc0c38d1 SR |
707 | cmdline_idx = 0; |
708 | } | |
709 | ||
69bb54ec SR |
710 | /** |
711 | * ftrace_off_permanent - disable all ftrace code permanently | |
712 | * | |
713 | * This should only be called when a serious anomally has | |
714 | * been detected. This will turn off the function tracing, | |
715 | * ring buffers, and other tracing utilites. It takes no | |
716 | * locks and can be called from any context. | |
717 | */ | |
718 | void ftrace_off_permanent(void) | |
719 | { | |
720 | tracing_disabled = 1; | |
721 | ftrace_stop(); | |
722 | tracing_off_permanent(); | |
723 | } | |
724 | ||
0f048701 SR |
725 | /** |
726 | * tracing_start - quick start of the tracer | |
727 | * | |
728 | * If tracing is enabled but was stopped by tracing_stop, | |
729 | * this will start the tracer back up. | |
730 | */ | |
731 | void tracing_start(void) | |
732 | { | |
733 | struct ring_buffer *buffer; | |
734 | unsigned long flags; | |
735 | ||
736 | if (tracing_disabled) | |
737 | return; | |
738 | ||
739 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
740 | if (--trace_stop_count) { |
741 | if (trace_stop_count < 0) { | |
742 | /* Someone screwed up their debugging */ | |
743 | WARN_ON_ONCE(1); | |
744 | trace_stop_count = 0; | |
745 | } | |
0f048701 SR |
746 | goto out; |
747 | } | |
748 | ||
749 | ||
750 | buffer = global_trace.buffer; | |
751 | if (buffer) | |
752 | ring_buffer_record_enable(buffer); | |
753 | ||
754 | buffer = max_tr.buffer; | |
755 | if (buffer) | |
756 | ring_buffer_record_enable(buffer); | |
757 | ||
758 | ftrace_start(); | |
759 | out: | |
760 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
761 | } | |
762 | ||
763 | /** | |
764 | * tracing_stop - quick stop of the tracer | |
765 | * | |
766 | * Light weight way to stop tracing. Use in conjunction with | |
767 | * tracing_start. | |
768 | */ | |
769 | void tracing_stop(void) | |
770 | { | |
771 | struct ring_buffer *buffer; | |
772 | unsigned long flags; | |
773 | ||
774 | ftrace_stop(); | |
775 | spin_lock_irqsave(&tracing_start_lock, flags); | |
776 | if (trace_stop_count++) | |
777 | goto out; | |
778 | ||
779 | buffer = global_trace.buffer; | |
780 | if (buffer) | |
781 | ring_buffer_record_disable(buffer); | |
782 | ||
783 | buffer = max_tr.buffer; | |
784 | if (buffer) | |
785 | ring_buffer_record_disable(buffer); | |
786 | ||
787 | out: | |
788 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
789 | } | |
790 | ||
e309b41d | 791 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 792 | |
e309b41d | 793 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 794 | { |
a635cf04 | 795 | unsigned pid, idx; |
bc0c38d1 SR |
796 | |
797 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
798 | return; | |
799 | ||
800 | /* | |
801 | * It's not the end of the world if we don't get | |
802 | * the lock, but we also don't want to spin | |
803 | * nor do we want to disable interrupts, | |
804 | * so if we miss here, then better luck next time. | |
805 | */ | |
efed792d | 806 | if (!__raw_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
807 | return; |
808 | ||
809 | idx = map_pid_to_cmdline[tsk->pid]; | |
2c7eea4c | 810 | if (idx == NO_CMDLINE_MAP) { |
bc0c38d1 SR |
811 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; |
812 | ||
a635cf04 CE |
813 | /* |
814 | * Check whether the cmdline buffer at idx has a pid | |
815 | * mapped. We are going to overwrite that entry so we | |
816 | * need to clear the map_pid_to_cmdline. Otherwise we | |
817 | * would read the new comm for the old pid. | |
818 | */ | |
819 | pid = map_cmdline_to_pid[idx]; | |
820 | if (pid != NO_CMDLINE_MAP) | |
821 | map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; | |
bc0c38d1 | 822 | |
a635cf04 | 823 | map_cmdline_to_pid[idx] = tsk->pid; |
bc0c38d1 SR |
824 | map_pid_to_cmdline[tsk->pid] = idx; |
825 | ||
826 | cmdline_idx = idx; | |
827 | } | |
828 | ||
829 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
830 | ||
efed792d | 831 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
832 | } |
833 | ||
4ca53085 | 834 | void trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 835 | { |
bc0c38d1 SR |
836 | unsigned map; |
837 | ||
4ca53085 SR |
838 | if (!pid) { |
839 | strcpy(comm, "<idle>"); | |
840 | return; | |
841 | } | |
bc0c38d1 | 842 | |
4ca53085 SR |
843 | if (pid > PID_MAX_DEFAULT) { |
844 | strcpy(comm, "<...>"); | |
845 | return; | |
846 | } | |
bc0c38d1 | 847 | |
5b6045a9 | 848 | preempt_disable(); |
4ca53085 | 849 | __raw_spin_lock(&trace_cmdline_lock); |
bc0c38d1 | 850 | map = map_pid_to_cmdline[pid]; |
50d88758 TG |
851 | if (map != NO_CMDLINE_MAP) |
852 | strcpy(comm, saved_cmdlines[map]); | |
853 | else | |
854 | strcpy(comm, "<...>"); | |
bc0c38d1 | 855 | |
4ca53085 | 856 | __raw_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 857 | preempt_enable(); |
bc0c38d1 SR |
858 | } |
859 | ||
e309b41d | 860 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 861 | { |
18aecd36 TG |
862 | if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled || |
863 | !tracing_is_on()) | |
bc0c38d1 SR |
864 | return; |
865 | ||
866 | trace_save_cmdline(tsk); | |
867 | } | |
868 | ||
45dcd8b8 | 869 | void |
38697053 SR |
870 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
871 | int pc) | |
bc0c38d1 SR |
872 | { |
873 | struct task_struct *tsk = current; | |
bc0c38d1 | 874 | |
777e208d SR |
875 | entry->preempt_count = pc & 0xff; |
876 | entry->pid = (tsk) ? tsk->pid : 0; | |
ef18012b | 877 | entry->tgid = (tsk) ? tsk->tgid : 0; |
777e208d | 878 | entry->flags = |
9244489a | 879 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 880 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
881 | #else |
882 | TRACE_FLAG_IRQS_NOSUPPORT | | |
883 | #endif | |
bc0c38d1 SR |
884 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
885 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
886 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
887 | } | |
f413cdb8 | 888 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 889 | |
51a763dd | 890 | struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr, |
7a4f453b | 891 | int type, |
51a763dd ACM |
892 | unsigned long len, |
893 | unsigned long flags, int pc) | |
894 | { | |
895 | struct ring_buffer_event *event; | |
896 | ||
897 | event = ring_buffer_lock_reserve(tr->buffer, len); | |
898 | if (event != NULL) { | |
899 | struct trace_entry *ent = ring_buffer_event_data(event); | |
900 | ||
901 | tracing_generic_entry_update(ent, flags, pc); | |
902 | ent->type = type; | |
903 | } | |
904 | ||
905 | return event; | |
906 | } | |
51a763dd | 907 | |
07edf712 FW |
908 | static inline void __trace_buffer_unlock_commit(struct trace_array *tr, |
909 | struct ring_buffer_event *event, | |
910 | unsigned long flags, int pc, | |
911 | int wake) | |
51a763dd ACM |
912 | { |
913 | ring_buffer_unlock_commit(tr->buffer, event); | |
914 | ||
915 | ftrace_trace_stack(tr, flags, 6, pc); | |
916 | ftrace_trace_userstack(tr, flags, pc); | |
07edf712 FW |
917 | |
918 | if (wake) | |
919 | trace_wake_up(); | |
920 | } | |
921 | ||
922 | void trace_buffer_unlock_commit(struct trace_array *tr, | |
923 | struct ring_buffer_event *event, | |
924 | unsigned long flags, int pc) | |
925 | { | |
926 | __trace_buffer_unlock_commit(tr, event, flags, pc, 1); | |
51a763dd ACM |
927 | } |
928 | ||
ef5580d0 | 929 | struct ring_buffer_event * |
7a4f453b | 930 | trace_current_buffer_lock_reserve(int type, unsigned long len, |
ef5580d0 SR |
931 | unsigned long flags, int pc) |
932 | { | |
933 | return trace_buffer_lock_reserve(&global_trace, | |
934 | type, len, flags, pc); | |
935 | } | |
94487d6d | 936 | EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); |
ef5580d0 SR |
937 | |
938 | void trace_current_buffer_unlock_commit(struct ring_buffer_event *event, | |
939 | unsigned long flags, int pc) | |
940 | { | |
77d9f465 | 941 | __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 1); |
07edf712 | 942 | } |
94487d6d | 943 | EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); |
07edf712 FW |
944 | |
945 | void trace_nowake_buffer_unlock_commit(struct ring_buffer_event *event, | |
946 | unsigned long flags, int pc) | |
947 | { | |
77d9f465 SR |
948 | __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 0); |
949 | } | |
94487d6d | 950 | EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit); |
77d9f465 SR |
951 | |
952 | void trace_current_buffer_discard_commit(struct ring_buffer_event *event) | |
953 | { | |
954 | ring_buffer_discard_commit(global_trace.buffer, event); | |
ef5580d0 | 955 | } |
12acd473 | 956 | EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit); |
ef5580d0 | 957 | |
e309b41d | 958 | void |
7be42151 | 959 | trace_function(struct trace_array *tr, |
38697053 SR |
960 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
961 | int pc) | |
bc0c38d1 | 962 | { |
e1112b4d | 963 | struct ftrace_event_call *call = &event_function; |
3928a8a2 | 964 | struct ring_buffer_event *event; |
777e208d | 965 | struct ftrace_entry *entry; |
bc0c38d1 | 966 | |
d769041f SR |
967 | /* If we are reading the ring buffer, don't trace */ |
968 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
969 | return; | |
970 | ||
51a763dd ACM |
971 | event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry), |
972 | flags, pc); | |
3928a8a2 SR |
973 | if (!event) |
974 | return; | |
975 | entry = ring_buffer_event_data(event); | |
777e208d SR |
976 | entry->ip = ip; |
977 | entry->parent_ip = parent_ip; | |
e1112b4d | 978 | |
eb02ce01 TZ |
979 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
980 | ring_buffer_unlock_commit(tr->buffer, event); | |
bc0c38d1 SR |
981 | } |
982 | ||
e309b41d | 983 | void |
2e0f5761 | 984 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
985 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
986 | int pc) | |
2e0f5761 IM |
987 | { |
988 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 989 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
990 | } |
991 | ||
c0a0d0d3 | 992 | #ifdef CONFIG_STACKTRACE |
53614991 | 993 | static void __ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
994 | unsigned long flags, |
995 | int skip, int pc) | |
86387f7e | 996 | { |
e1112b4d | 997 | struct ftrace_event_call *call = &event_kernel_stack; |
3928a8a2 | 998 | struct ring_buffer_event *event; |
777e208d | 999 | struct stack_entry *entry; |
86387f7e IM |
1000 | struct stack_trace trace; |
1001 | ||
51a763dd ACM |
1002 | event = trace_buffer_lock_reserve(tr, TRACE_STACK, |
1003 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1004 | if (!event) |
1005 | return; | |
1006 | entry = ring_buffer_event_data(event); | |
777e208d | 1007 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
1008 | |
1009 | trace.nr_entries = 0; | |
1010 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1011 | trace.skip = skip; | |
777e208d | 1012 | trace.entries = entry->caller; |
86387f7e IM |
1013 | |
1014 | save_stack_trace(&trace); | |
eb02ce01 TZ |
1015 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1016 | ring_buffer_unlock_commit(tr->buffer, event); | |
f0a920d5 IM |
1017 | } |
1018 | ||
c0a0d0d3 FW |
1019 | void ftrace_trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1020 | int pc) | |
53614991 SR |
1021 | { |
1022 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
1023 | return; | |
1024 | ||
7be42151 | 1025 | __ftrace_trace_stack(tr, flags, skip, pc); |
53614991 SR |
1026 | } |
1027 | ||
c0a0d0d3 FW |
1028 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
1029 | int pc) | |
38697053 | 1030 | { |
7be42151 | 1031 | __ftrace_trace_stack(tr, flags, skip, pc); |
38697053 SR |
1032 | } |
1033 | ||
c0a0d0d3 | 1034 | void ftrace_trace_userstack(struct trace_array *tr, unsigned long flags, int pc) |
02b67518 | 1035 | { |
e1112b4d | 1036 | struct ftrace_event_call *call = &event_user_stack; |
8d7c6a96 | 1037 | struct ring_buffer_event *event; |
02b67518 TE |
1038 | struct userstack_entry *entry; |
1039 | struct stack_trace trace; | |
02b67518 TE |
1040 | |
1041 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
1042 | return; | |
1043 | ||
51a763dd ACM |
1044 | event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK, |
1045 | sizeof(*entry), flags, pc); | |
02b67518 TE |
1046 | if (!event) |
1047 | return; | |
1048 | entry = ring_buffer_event_data(event); | |
02b67518 TE |
1049 | |
1050 | memset(&entry->caller, 0, sizeof(entry->caller)); | |
1051 | ||
1052 | trace.nr_entries = 0; | |
1053 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
1054 | trace.skip = 0; | |
1055 | trace.entries = entry->caller; | |
1056 | ||
1057 | save_stack_trace_user(&trace); | |
eb02ce01 TZ |
1058 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1059 | ring_buffer_unlock_commit(tr->buffer, event); | |
02b67518 TE |
1060 | } |
1061 | ||
4fd27358 HE |
1062 | #ifdef UNUSED |
1063 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1064 | { |
7be42151 | 1065 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1066 | } |
4fd27358 | 1067 | #endif /* UNUSED */ |
02b67518 | 1068 | |
c0a0d0d3 FW |
1069 | #endif /* CONFIG_STACKTRACE */ |
1070 | ||
38697053 | 1071 | static void |
7be42151 | 1072 | ftrace_trace_special(void *__tr, |
38697053 SR |
1073 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1074 | int pc) | |
a4feb834 | 1075 | { |
3928a8a2 | 1076 | struct ring_buffer_event *event; |
a4feb834 | 1077 | struct trace_array *tr = __tr; |
777e208d | 1078 | struct special_entry *entry; |
a4feb834 | 1079 | |
51a763dd ACM |
1080 | event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL, |
1081 | sizeof(*entry), 0, pc); | |
3928a8a2 SR |
1082 | if (!event) |
1083 | return; | |
1084 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1085 | entry->arg1 = arg1; |
1086 | entry->arg2 = arg2; | |
1087 | entry->arg3 = arg3; | |
51a763dd | 1088 | trace_buffer_unlock_commit(tr, event, 0, pc); |
a4feb834 IM |
1089 | } |
1090 | ||
38697053 SR |
1091 | void |
1092 | __trace_special(void *__tr, void *__data, | |
1093 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1094 | { | |
7be42151 | 1095 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1096 | } |
1097 | ||
4902f884 SR |
1098 | void |
1099 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1100 | { | |
1101 | struct trace_array *tr = &global_trace; | |
1102 | struct trace_array_cpu *data; | |
5aa1ba6a | 1103 | unsigned long flags; |
4902f884 | 1104 | int cpu; |
38697053 | 1105 | int pc; |
4902f884 | 1106 | |
c76f0694 | 1107 | if (tracing_disabled) |
4902f884 SR |
1108 | return; |
1109 | ||
38697053 | 1110 | pc = preempt_count(); |
5aa1ba6a | 1111 | local_irq_save(flags); |
4902f884 SR |
1112 | cpu = raw_smp_processor_id(); |
1113 | data = tr->data[cpu]; | |
4902f884 | 1114 | |
5aa1ba6a | 1115 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1116 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1117 | |
5aa1ba6a SR |
1118 | atomic_dec(&data->disabled); |
1119 | local_irq_restore(flags); | |
4902f884 SR |
1120 | } |
1121 | ||
769b0441 | 1122 | /** |
48ead020 | 1123 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
1124 | * |
1125 | */ | |
40ce74f1 | 1126 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 1127 | { |
80370cb7 SR |
1128 | static raw_spinlock_t trace_buf_lock = |
1129 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
769b0441 FW |
1130 | static u32 trace_buf[TRACE_BUF_SIZE]; |
1131 | ||
e1112b4d | 1132 | struct ftrace_event_call *call = &event_bprint; |
769b0441 FW |
1133 | struct ring_buffer_event *event; |
1134 | struct trace_array *tr = &global_trace; | |
1135 | struct trace_array_cpu *data; | |
48ead020 | 1136 | struct bprint_entry *entry; |
769b0441 | 1137 | unsigned long flags; |
3189cdb3 | 1138 | int disable; |
769b0441 FW |
1139 | int resched; |
1140 | int cpu, len = 0, size, pc; | |
1141 | ||
1142 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
1143 | return 0; | |
1144 | ||
1145 | /* Don't pollute graph traces with trace_vprintk internals */ | |
1146 | pause_graph_tracing(); | |
1147 | ||
1148 | pc = preempt_count(); | |
1149 | resched = ftrace_preempt_disable(); | |
1150 | cpu = raw_smp_processor_id(); | |
1151 | data = tr->data[cpu]; | |
1152 | ||
3189cdb3 SR |
1153 | disable = atomic_inc_return(&data->disabled); |
1154 | if (unlikely(disable != 1)) | |
769b0441 FW |
1155 | goto out; |
1156 | ||
80370cb7 SR |
1157 | /* Lockdep uses trace_printk for lock tracing */ |
1158 | local_irq_save(flags); | |
1159 | __raw_spin_lock(&trace_buf_lock); | |
769b0441 FW |
1160 | len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
1161 | ||
1162 | if (len > TRACE_BUF_SIZE || len < 0) | |
1163 | goto out_unlock; | |
1164 | ||
1165 | size = sizeof(*entry) + sizeof(u32) * len; | |
48ead020 | 1166 | event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc); |
769b0441 FW |
1167 | if (!event) |
1168 | goto out_unlock; | |
1169 | entry = ring_buffer_event_data(event); | |
1170 | entry->ip = ip; | |
769b0441 FW |
1171 | entry->fmt = fmt; |
1172 | ||
1173 | memcpy(entry->buf, trace_buf, sizeof(u32) * len); | |
eb02ce01 TZ |
1174 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1175 | ring_buffer_unlock_commit(tr->buffer, event); | |
769b0441 FW |
1176 | |
1177 | out_unlock: | |
80370cb7 SR |
1178 | __raw_spin_unlock(&trace_buf_lock); |
1179 | local_irq_restore(flags); | |
769b0441 FW |
1180 | |
1181 | out: | |
3189cdb3 | 1182 | atomic_dec_return(&data->disabled); |
769b0441 FW |
1183 | ftrace_preempt_enable(resched); |
1184 | unpause_graph_tracing(); | |
1185 | ||
1186 | return len; | |
1187 | } | |
48ead020 FW |
1188 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
1189 | ||
40ce74f1 | 1190 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
48ead020 FW |
1191 | { |
1192 | static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; | |
1193 | static char trace_buf[TRACE_BUF_SIZE]; | |
1194 | ||
e1112b4d | 1195 | struct ftrace_event_call *call = &event_print; |
48ead020 FW |
1196 | struct ring_buffer_event *event; |
1197 | struct trace_array *tr = &global_trace; | |
1198 | struct trace_array_cpu *data; | |
1199 | int cpu, len = 0, size, pc; | |
1200 | struct print_entry *entry; | |
1201 | unsigned long irq_flags; | |
3189cdb3 | 1202 | int disable; |
48ead020 FW |
1203 | |
1204 | if (tracing_disabled || tracing_selftest_running) | |
1205 | return 0; | |
1206 | ||
1207 | pc = preempt_count(); | |
1208 | preempt_disable_notrace(); | |
1209 | cpu = raw_smp_processor_id(); | |
1210 | data = tr->data[cpu]; | |
1211 | ||
3189cdb3 SR |
1212 | disable = atomic_inc_return(&data->disabled); |
1213 | if (unlikely(disable != 1)) | |
48ead020 FW |
1214 | goto out; |
1215 | ||
1216 | pause_graph_tracing(); | |
1217 | raw_local_irq_save(irq_flags); | |
1218 | __raw_spin_lock(&trace_buf_lock); | |
1219 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); | |
1220 | ||
1221 | len = min(len, TRACE_BUF_SIZE-1); | |
1222 | trace_buf[len] = 0; | |
1223 | ||
1224 | size = sizeof(*entry) + len + 1; | |
1225 | event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc); | |
1226 | if (!event) | |
1227 | goto out_unlock; | |
1228 | entry = ring_buffer_event_data(event); | |
1229 | entry->ip = ip; | |
48ead020 FW |
1230 | |
1231 | memcpy(&entry->buf, trace_buf, len); | |
1232 | entry->buf[len] = 0; | |
eb02ce01 TZ |
1233 | if (!filter_check_discard(call, entry, tr->buffer, event)) |
1234 | ring_buffer_unlock_commit(tr->buffer, event); | |
48ead020 FW |
1235 | |
1236 | out_unlock: | |
1237 | __raw_spin_unlock(&trace_buf_lock); | |
1238 | raw_local_irq_restore(irq_flags); | |
1239 | unpause_graph_tracing(); | |
1240 | out: | |
3189cdb3 | 1241 | atomic_dec_return(&data->disabled); |
48ead020 FW |
1242 | preempt_enable_notrace(); |
1243 | ||
1244 | return len; | |
1245 | } | |
769b0441 FW |
1246 | EXPORT_SYMBOL_GPL(trace_vprintk); |
1247 | ||
bc0c38d1 SR |
1248 | enum trace_file_type { |
1249 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1250 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1251 | }; |
1252 | ||
e2ac8ef5 | 1253 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1254 | { |
d769041f SR |
1255 | /* Don't allow ftrace to trace into the ring buffers */ |
1256 | ftrace_disable_cpu(); | |
1257 | ||
5a90f577 | 1258 | iter->idx++; |
d769041f SR |
1259 | if (iter->buffer_iter[iter->cpu]) |
1260 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1261 | ||
1262 | ftrace_enable_cpu(); | |
5a90f577 SR |
1263 | } |
1264 | ||
e309b41d | 1265 | static struct trace_entry * |
3928a8a2 | 1266 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1267 | { |
3928a8a2 SR |
1268 | struct ring_buffer_event *event; |
1269 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1270 | |
d769041f SR |
1271 | /* Don't allow ftrace to trace into the ring buffers */ |
1272 | ftrace_disable_cpu(); | |
1273 | ||
1274 | if (buf_iter) | |
1275 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1276 | else | |
1277 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1278 | ||
1279 | ftrace_enable_cpu(); | |
1280 | ||
3928a8a2 | 1281 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1282 | } |
d769041f | 1283 | |
dd0e545f | 1284 | static struct trace_entry * |
3928a8a2 | 1285 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1286 | { |
3928a8a2 | 1287 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1288 | struct trace_entry *ent, *next = NULL; |
b04cc6b1 | 1289 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1290 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1291 | int next_cpu = -1; |
1292 | int cpu; | |
1293 | ||
b04cc6b1 FW |
1294 | /* |
1295 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1296 | * all cpu and peek directly. | |
1297 | */ | |
1298 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1299 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1300 | return NULL; | |
1301 | ent = peek_next_entry(iter, cpu_file, ent_ts); | |
1302 | if (ent_cpu) | |
1303 | *ent_cpu = cpu_file; | |
1304 | ||
1305 | return ent; | |
1306 | } | |
1307 | ||
ab46428c | 1308 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1309 | |
3928a8a2 SR |
1310 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1311 | continue; | |
dd0e545f | 1312 | |
3928a8a2 | 1313 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1314 | |
cdd31cd2 IM |
1315 | /* |
1316 | * Pick the entry with the smallest timestamp: | |
1317 | */ | |
3928a8a2 | 1318 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1319 | next = ent; |
1320 | next_cpu = cpu; | |
3928a8a2 | 1321 | next_ts = ts; |
bc0c38d1 SR |
1322 | } |
1323 | } | |
1324 | ||
1325 | if (ent_cpu) | |
1326 | *ent_cpu = next_cpu; | |
1327 | ||
3928a8a2 SR |
1328 | if (ent_ts) |
1329 | *ent_ts = next_ts; | |
1330 | ||
bc0c38d1 SR |
1331 | return next; |
1332 | } | |
1333 | ||
dd0e545f | 1334 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1335 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1336 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1337 | { |
3928a8a2 | 1338 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1339 | } |
1340 | ||
1341 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1342 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1343 | { | |
3928a8a2 | 1344 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1345 | |
3928a8a2 | 1346 | if (iter->ent) |
e2ac8ef5 | 1347 | trace_iterator_increment(iter); |
dd0e545f | 1348 | |
3928a8a2 | 1349 | return iter->ent ? iter : NULL; |
b3806b43 | 1350 | } |
bc0c38d1 | 1351 | |
e309b41d | 1352 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1353 | { |
d769041f SR |
1354 | /* Don't allow ftrace to trace into the ring buffers */ |
1355 | ftrace_disable_cpu(); | |
3928a8a2 | 1356 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1357 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1358 | } |
1359 | ||
e309b41d | 1360 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1361 | { |
1362 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1363 | int i = (int)*pos; |
4e3c3333 | 1364 | void *ent; |
bc0c38d1 SR |
1365 | |
1366 | (*pos)++; | |
1367 | ||
1368 | /* can't go backwards */ | |
1369 | if (iter->idx > i) | |
1370 | return NULL; | |
1371 | ||
1372 | if (iter->idx < 0) | |
1373 | ent = find_next_entry_inc(iter); | |
1374 | else | |
1375 | ent = iter; | |
1376 | ||
1377 | while (ent && iter->idx < i) | |
1378 | ent = find_next_entry_inc(iter); | |
1379 | ||
1380 | iter->pos = *pos; | |
1381 | ||
bc0c38d1 SR |
1382 | return ent; |
1383 | } | |
1384 | ||
2f26ebd5 SR |
1385 | static void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
1386 | { | |
1387 | struct trace_array *tr = iter->tr; | |
1388 | struct ring_buffer_event *event; | |
1389 | struct ring_buffer_iter *buf_iter; | |
1390 | unsigned long entries = 0; | |
1391 | u64 ts; | |
1392 | ||
1393 | tr->data[cpu]->skipped_entries = 0; | |
1394 | ||
1395 | if (!iter->buffer_iter[cpu]) | |
1396 | return; | |
1397 | ||
1398 | buf_iter = iter->buffer_iter[cpu]; | |
1399 | ring_buffer_iter_reset(buf_iter); | |
1400 | ||
1401 | /* | |
1402 | * We could have the case with the max latency tracers | |
1403 | * that a reset never took place on a cpu. This is evident | |
1404 | * by the timestamp being before the start of the buffer. | |
1405 | */ | |
1406 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
1407 | if (ts >= iter->tr->time_start) | |
1408 | break; | |
1409 | entries++; | |
1410 | ring_buffer_read(buf_iter, NULL); | |
1411 | } | |
1412 | ||
1413 | tr->data[cpu]->skipped_entries = entries; | |
1414 | } | |
1415 | ||
d7350c3f FW |
1416 | /* |
1417 | * No necessary locking here. The worst thing which can | |
1418 | * happen is loosing events consumed at the same time | |
1419 | * by a trace_pipe reader. | |
1420 | * Other than that, we don't risk to crash the ring buffer | |
1421 | * because it serializes the readers. | |
1422 | * | |
1423 | * The current tracer is copied to avoid a global locking | |
1424 | * all around. | |
1425 | */ | |
bc0c38d1 SR |
1426 | static void *s_start(struct seq_file *m, loff_t *pos) |
1427 | { | |
1428 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1429 | static struct tracer *old_tracer; |
b04cc6b1 | 1430 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1431 | void *p = NULL; |
1432 | loff_t l = 0; | |
3928a8a2 | 1433 | int cpu; |
bc0c38d1 | 1434 | |
d7350c3f | 1435 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1436 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1437 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1438 | old_tracer = current_trace; | |
1439 | *iter->trace = *current_trace; | |
d15f57f2 | 1440 | } |
d7350c3f | 1441 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1442 | |
1443 | atomic_inc(&trace_record_cmdline_disabled); | |
1444 | ||
bc0c38d1 SR |
1445 | if (*pos != iter->pos) { |
1446 | iter->ent = NULL; | |
1447 | iter->cpu = 0; | |
1448 | iter->idx = -1; | |
1449 | ||
d769041f SR |
1450 | ftrace_disable_cpu(); |
1451 | ||
b04cc6b1 FW |
1452 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1453 | for_each_tracing_cpu(cpu) | |
2f26ebd5 | 1454 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 1455 | } else |
2f26ebd5 | 1456 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 1457 | |
d769041f SR |
1458 | ftrace_enable_cpu(); |
1459 | ||
bc0c38d1 SR |
1460 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1461 | ; | |
1462 | ||
1463 | } else { | |
4c11d7ae | 1464 | l = *pos - 1; |
bc0c38d1 SR |
1465 | p = s_next(m, p, &l); |
1466 | } | |
1467 | ||
4f535968 | 1468 | trace_event_read_lock(); |
bc0c38d1 SR |
1469 | return p; |
1470 | } | |
1471 | ||
1472 | static void s_stop(struct seq_file *m, void *p) | |
1473 | { | |
bc0c38d1 | 1474 | atomic_dec(&trace_record_cmdline_disabled); |
4f535968 | 1475 | trace_event_read_unlock(); |
bc0c38d1 SR |
1476 | } |
1477 | ||
e309b41d | 1478 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1479 | { |
a6168353 ME |
1480 | seq_puts(m, "# _------=> CPU# \n"); |
1481 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1482 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1483 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1484 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1485 | seq_puts(m, "# |||| / \n"); | |
1486 | seq_puts(m, "# ||||| delay \n"); | |
1487 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1488 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1489 | } |
1490 | ||
e309b41d | 1491 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1492 | { |
a6168353 ME |
1493 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1494 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1495 | } |
1496 | ||
1497 | ||
e309b41d | 1498 | static void |
bc0c38d1 SR |
1499 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1500 | { | |
1501 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1502 | struct trace_array *tr = iter->tr; | |
1503 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1504 | struct tracer *type = current_trace; | |
2f26ebd5 SR |
1505 | unsigned long entries = 0; |
1506 | unsigned long total = 0; | |
1507 | unsigned long count; | |
bc0c38d1 | 1508 | const char *name = "preemption"; |
2f26ebd5 | 1509 | int cpu; |
bc0c38d1 SR |
1510 | |
1511 | if (type) | |
1512 | name = type->name; | |
1513 | ||
2f26ebd5 SR |
1514 | |
1515 | for_each_tracing_cpu(cpu) { | |
1516 | count = ring_buffer_entries_cpu(tr->buffer, cpu); | |
1517 | /* | |
1518 | * If this buffer has skipped entries, then we hold all | |
1519 | * entries for the trace and we need to ignore the | |
1520 | * ones before the time stamp. | |
1521 | */ | |
1522 | if (tr->data[cpu]->skipped_entries) { | |
1523 | count -= tr->data[cpu]->skipped_entries; | |
1524 | /* total is the same as the entries */ | |
1525 | total += count; | |
1526 | } else | |
1527 | total += count + | |
1528 | ring_buffer_overrun_cpu(tr->buffer, cpu); | |
1529 | entries += count; | |
1530 | } | |
bc0c38d1 | 1531 | |
888b55dc | 1532 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 1533 | name, UTS_RELEASE); |
888b55dc | 1534 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 1535 | "---------------------------------\n"); |
888b55dc | 1536 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 1537 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 1538 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1539 | entries, |
4c11d7ae | 1540 | total, |
bc0c38d1 SR |
1541 | tr->cpu, |
1542 | #if defined(CONFIG_PREEMPT_NONE) | |
1543 | "server", | |
1544 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1545 | "desktop", | |
b5c21b45 | 1546 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1547 | "preempt", |
1548 | #else | |
1549 | "unknown", | |
1550 | #endif | |
1551 | /* These are reserved for later use */ | |
1552 | 0, 0, 0, 0); | |
1553 | #ifdef CONFIG_SMP | |
1554 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1555 | #else | |
1556 | seq_puts(m, ")\n"); | |
1557 | #endif | |
888b55dc KM |
1558 | seq_puts(m, "# -----------------\n"); |
1559 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 SR |
1560 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
1561 | data->comm, data->pid, data->uid, data->nice, | |
1562 | data->policy, data->rt_priority); | |
888b55dc | 1563 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
1564 | |
1565 | if (data->critical_start) { | |
888b55dc | 1566 | seq_puts(m, "# => started at: "); |
214023c3 SR |
1567 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1568 | trace_print_seq(m, &iter->seq); | |
888b55dc | 1569 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
1570 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1571 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 1572 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
1573 | } |
1574 | ||
888b55dc | 1575 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
1576 | } |
1577 | ||
a309720c SR |
1578 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1579 | { | |
1580 | struct trace_seq *s = &iter->seq; | |
1581 | ||
12ef7d44 SR |
1582 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1583 | return; | |
1584 | ||
1585 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1586 | return; | |
1587 | ||
4462344e | 1588 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1589 | return; |
1590 | ||
2f26ebd5 SR |
1591 | if (iter->tr->data[iter->cpu]->skipped_entries) |
1592 | return; | |
1593 | ||
4462344e | 1594 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
1595 | |
1596 | /* Don't print started cpu buffer for the first entry of the trace */ | |
1597 | if (iter->idx > 1) | |
1598 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
1599 | iter->cpu); | |
a309720c SR |
1600 | } |
1601 | ||
2c4f035f | 1602 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1603 | { |
214023c3 | 1604 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1605 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1606 | struct trace_entry *entry; |
f633cef0 | 1607 | struct trace_event *event; |
bc0c38d1 | 1608 | |
4e3c3333 | 1609 | entry = iter->ent; |
dd0e545f | 1610 | |
a309720c SR |
1611 | test_cpu_buff_start(iter); |
1612 | ||
c4a8e8be | 1613 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1614 | |
c4a8e8be | 1615 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
27d48be8 SR |
1616 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
1617 | if (!trace_print_lat_context(iter)) | |
1618 | goto partial; | |
1619 | } else { | |
1620 | if (!trace_print_context(iter)) | |
1621 | goto partial; | |
1622 | } | |
c4a8e8be | 1623 | } |
bc0c38d1 | 1624 | |
268ccda0 | 1625 | if (event) |
d9793bd8 ACM |
1626 | return event->trace(iter, sym_flags); |
1627 | ||
1628 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1629 | goto partial; | |
02b67518 | 1630 | |
2c4f035f | 1631 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1632 | partial: |
1633 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1634 | } |
1635 | ||
2c4f035f | 1636 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1637 | { |
1638 | struct trace_seq *s = &iter->seq; | |
1639 | struct trace_entry *entry; | |
f633cef0 | 1640 | struct trace_event *event; |
f9896bf3 IM |
1641 | |
1642 | entry = iter->ent; | |
dd0e545f | 1643 | |
c4a8e8be | 1644 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1645 | if (!trace_seq_printf(s, "%d %d %llu ", |
1646 | entry->pid, iter->cpu, iter->ts)) | |
1647 | goto partial; | |
c4a8e8be | 1648 | } |
f9896bf3 | 1649 | |
f633cef0 | 1650 | event = ftrace_find_event(entry->type); |
268ccda0 | 1651 | if (event) |
d9793bd8 ACM |
1652 | return event->raw(iter, 0); |
1653 | ||
1654 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1655 | goto partial; | |
777e208d | 1656 | |
2c4f035f | 1657 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1658 | partial: |
1659 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1660 | } |
1661 | ||
2c4f035f | 1662 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1663 | { |
1664 | struct trace_seq *s = &iter->seq; | |
1665 | unsigned char newline = '\n'; | |
1666 | struct trace_entry *entry; | |
f633cef0 | 1667 | struct trace_event *event; |
5e3ca0ec IM |
1668 | |
1669 | entry = iter->ent; | |
dd0e545f | 1670 | |
c4a8e8be FW |
1671 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1672 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1673 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1674 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1675 | } | |
5e3ca0ec | 1676 | |
f633cef0 | 1677 | event = ftrace_find_event(entry->type); |
268ccda0 | 1678 | if (event) { |
ae7462b4 | 1679 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1680 | if (ret != TRACE_TYPE_HANDLED) |
1681 | return ret; | |
1682 | } | |
7104f300 | 1683 | |
5e3ca0ec IM |
1684 | SEQ_PUT_FIELD_RET(s, newline); |
1685 | ||
2c4f035f | 1686 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1687 | } |
1688 | ||
2c4f035f | 1689 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1690 | { |
1691 | struct trace_seq *s = &iter->seq; | |
1692 | struct trace_entry *entry; | |
f633cef0 | 1693 | struct trace_event *event; |
cb0f12aa IM |
1694 | |
1695 | entry = iter->ent; | |
dd0e545f | 1696 | |
c4a8e8be FW |
1697 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1698 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1699 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1700 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1701 | } | |
cb0f12aa | 1702 | |
f633cef0 | 1703 | event = ftrace_find_event(entry->type); |
268ccda0 | 1704 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1705 | } |
1706 | ||
bc0c38d1 SR |
1707 | static int trace_empty(struct trace_iterator *iter) |
1708 | { | |
bc0c38d1 SR |
1709 | int cpu; |
1710 | ||
9aba60fe SR |
1711 | /* If we are looking at one CPU buffer, only check that one */ |
1712 | if (iter->cpu_file != TRACE_PIPE_ALL_CPU) { | |
1713 | cpu = iter->cpu_file; | |
1714 | if (iter->buffer_iter[cpu]) { | |
1715 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1716 | return 0; | |
1717 | } else { | |
1718 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1719 | return 0; | |
1720 | } | |
1721 | return 1; | |
1722 | } | |
1723 | ||
ab46428c | 1724 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1725 | if (iter->buffer_iter[cpu]) { |
1726 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1727 | return 0; | |
1728 | } else { | |
1729 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1730 | return 0; | |
1731 | } | |
bc0c38d1 | 1732 | } |
d769041f | 1733 | |
797d3712 | 1734 | return 1; |
bc0c38d1 SR |
1735 | } |
1736 | ||
4f535968 | 1737 | /* Called with trace_event_read_lock() held. */ |
2c4f035f | 1738 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1739 | { |
2c4f035f FW |
1740 | enum print_line_t ret; |
1741 | ||
1742 | if (iter->trace && iter->trace->print_line) { | |
1743 | ret = iter->trace->print_line(iter); | |
1744 | if (ret != TRACE_TYPE_UNHANDLED) | |
1745 | return ret; | |
1746 | } | |
72829bc3 | 1747 | |
48ead020 FW |
1748 | if (iter->ent->type == TRACE_BPRINT && |
1749 | trace_flags & TRACE_ITER_PRINTK && | |
1750 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1751 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 1752 | |
66896a85 FW |
1753 | if (iter->ent->type == TRACE_PRINT && |
1754 | trace_flags & TRACE_ITER_PRINTK && | |
1755 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 1756 | return trace_print_printk_msg_only(iter); |
66896a85 | 1757 | |
cb0f12aa IM |
1758 | if (trace_flags & TRACE_ITER_BIN) |
1759 | return print_bin_fmt(iter); | |
1760 | ||
5e3ca0ec IM |
1761 | if (trace_flags & TRACE_ITER_HEX) |
1762 | return print_hex_fmt(iter); | |
1763 | ||
f9896bf3 IM |
1764 | if (trace_flags & TRACE_ITER_RAW) |
1765 | return print_raw_fmt(iter); | |
1766 | ||
f9896bf3 IM |
1767 | return print_trace_fmt(iter); |
1768 | } | |
1769 | ||
bc0c38d1 SR |
1770 | static int s_show(struct seq_file *m, void *v) |
1771 | { | |
1772 | struct trace_iterator *iter = v; | |
1773 | ||
1774 | if (iter->ent == NULL) { | |
1775 | if (iter->tr) { | |
1776 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1777 | seq_puts(m, "#\n"); | |
1778 | } | |
8bba1bf5 MM |
1779 | if (iter->trace && iter->trace->print_header) |
1780 | iter->trace->print_header(m); | |
1781 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
1782 | /* print nothing if the buffers are empty */ |
1783 | if (trace_empty(iter)) | |
1784 | return 0; | |
1785 | print_trace_header(m, iter); | |
1786 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1787 | print_lat_help_header(m); | |
1788 | } else { | |
1789 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1790 | print_func_help_header(m); | |
1791 | } | |
1792 | } else { | |
f9896bf3 | 1793 | print_trace_line(iter); |
214023c3 | 1794 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1795 | } |
1796 | ||
1797 | return 0; | |
1798 | } | |
1799 | ||
1800 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1801 | .start = s_start, |
1802 | .next = s_next, | |
1803 | .stop = s_stop, | |
1804 | .show = s_show, | |
bc0c38d1 SR |
1805 | }; |
1806 | ||
e309b41d | 1807 | static struct trace_iterator * |
85a2f9b4 | 1808 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 1809 | { |
b04cc6b1 | 1810 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 1811 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 1812 | struct trace_iterator *iter; |
3928a8a2 | 1813 | struct seq_file *m; |
85a2f9b4 | 1814 | int cpu, ret; |
bc0c38d1 | 1815 | |
85a2f9b4 SR |
1816 | if (tracing_disabled) |
1817 | return ERR_PTR(-ENODEV); | |
60a11774 | 1818 | |
bc0c38d1 | 1819 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
1820 | if (!iter) |
1821 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 1822 | |
d7350c3f FW |
1823 | /* |
1824 | * We make a copy of the current tracer to avoid concurrent | |
1825 | * changes on it while we are reading. | |
1826 | */ | |
bc0c38d1 | 1827 | mutex_lock(&trace_types_lock); |
d7350c3f | 1828 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 1829 | if (!iter->trace) |
d7350c3f | 1830 | goto fail; |
85a2f9b4 | 1831 | |
d7350c3f FW |
1832 | if (current_trace) |
1833 | *iter->trace = *current_trace; | |
1834 | ||
b0dfa978 FW |
1835 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) |
1836 | goto fail; | |
1837 | ||
1838 | cpumask_clear(iter->started); | |
1839 | ||
bc0c38d1 SR |
1840 | if (current_trace && current_trace->print_max) |
1841 | iter->tr = &max_tr; | |
1842 | else | |
b04cc6b1 | 1843 | iter->tr = &global_trace; |
bc0c38d1 | 1844 | iter->pos = -1; |
d7350c3f | 1845 | mutex_init(&iter->mutex); |
b04cc6b1 | 1846 | iter->cpu_file = cpu_file; |
bc0c38d1 | 1847 | |
8bba1bf5 MM |
1848 | /* Notify the tracer early; before we stop tracing. */ |
1849 | if (iter->trace && iter->trace->open) | |
a93751ca | 1850 | iter->trace->open(iter); |
8bba1bf5 | 1851 | |
12ef7d44 SR |
1852 | /* Annotate start of buffers if we had overruns */ |
1853 | if (ring_buffer_overruns(iter->tr->buffer)) | |
1854 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
1855 | ||
2f26ebd5 SR |
1856 | /* stop the trace while dumping */ |
1857 | tracing_stop(); | |
1858 | ||
b04cc6b1 FW |
1859 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
1860 | for_each_tracing_cpu(cpu) { | |
12ef7d44 | 1861 | |
b04cc6b1 FW |
1862 | iter->buffer_iter[cpu] = |
1863 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
2f26ebd5 | 1864 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
1865 | } |
1866 | } else { | |
1867 | cpu = iter->cpu_file; | |
3928a8a2 | 1868 | iter->buffer_iter[cpu] = |
b04cc6b1 | 1869 | ring_buffer_read_start(iter->tr->buffer, cpu); |
2f26ebd5 | 1870 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
1871 | } |
1872 | ||
85a2f9b4 SR |
1873 | ret = seq_open(file, &tracer_seq_ops); |
1874 | if (ret < 0) { | |
1875 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 1876 | goto fail_buffer; |
85a2f9b4 | 1877 | } |
bc0c38d1 | 1878 | |
3928a8a2 SR |
1879 | m = file->private_data; |
1880 | m->private = iter; | |
bc0c38d1 | 1881 | |
bc0c38d1 SR |
1882 | mutex_unlock(&trace_types_lock); |
1883 | ||
bc0c38d1 | 1884 | return iter; |
3928a8a2 SR |
1885 | |
1886 | fail_buffer: | |
1887 | for_each_tracing_cpu(cpu) { | |
1888 | if (iter->buffer_iter[cpu]) | |
1889 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1890 | } | |
b0dfa978 | 1891 | free_cpumask_var(iter->started); |
2f26ebd5 | 1892 | tracing_start(); |
d7350c3f | 1893 | fail: |
3928a8a2 | 1894 | mutex_unlock(&trace_types_lock); |
d7350c3f | 1895 | kfree(iter->trace); |
0bb943c7 | 1896 | kfree(iter); |
3928a8a2 | 1897 | |
85a2f9b4 | 1898 | return fail_ret; |
bc0c38d1 SR |
1899 | } |
1900 | ||
1901 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1902 | { | |
60a11774 SR |
1903 | if (tracing_disabled) |
1904 | return -ENODEV; | |
1905 | ||
bc0c38d1 SR |
1906 | filp->private_data = inode->i_private; |
1907 | return 0; | |
1908 | } | |
1909 | ||
4fd27358 | 1910 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
1911 | { |
1912 | struct seq_file *m = (struct seq_file *)file->private_data; | |
4acd4d00 | 1913 | struct trace_iterator *iter; |
3928a8a2 | 1914 | int cpu; |
bc0c38d1 | 1915 | |
4acd4d00 SR |
1916 | if (!(file->f_mode & FMODE_READ)) |
1917 | return 0; | |
1918 | ||
1919 | iter = m->private; | |
1920 | ||
bc0c38d1 | 1921 | mutex_lock(&trace_types_lock); |
3928a8a2 SR |
1922 | for_each_tracing_cpu(cpu) { |
1923 | if (iter->buffer_iter[cpu]) | |
1924 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1925 | } | |
1926 | ||
bc0c38d1 SR |
1927 | if (iter->trace && iter->trace->close) |
1928 | iter->trace->close(iter); | |
1929 | ||
1930 | /* reenable tracing if it was previously enabled */ | |
9036990d | 1931 | tracing_start(); |
bc0c38d1 SR |
1932 | mutex_unlock(&trace_types_lock); |
1933 | ||
1934 | seq_release(inode, file); | |
d7350c3f | 1935 | mutex_destroy(&iter->mutex); |
b0dfa978 | 1936 | free_cpumask_var(iter->started); |
d7350c3f | 1937 | kfree(iter->trace); |
bc0c38d1 SR |
1938 | kfree(iter); |
1939 | return 0; | |
1940 | } | |
1941 | ||
1942 | static int tracing_open(struct inode *inode, struct file *file) | |
1943 | { | |
85a2f9b4 SR |
1944 | struct trace_iterator *iter; |
1945 | int ret = 0; | |
bc0c38d1 | 1946 | |
4acd4d00 SR |
1947 | /* If this file was open for write, then erase contents */ |
1948 | if ((file->f_mode & FMODE_WRITE) && | |
8650ae32 | 1949 | (file->f_flags & O_TRUNC)) { |
4acd4d00 | 1950 | long cpu = (long) inode->i_private; |
bc0c38d1 | 1951 | |
4acd4d00 SR |
1952 | if (cpu == TRACE_PIPE_ALL_CPU) |
1953 | tracing_reset_online_cpus(&global_trace); | |
1954 | else | |
1955 | tracing_reset(&global_trace, cpu); | |
1956 | } | |
bc0c38d1 | 1957 | |
4acd4d00 SR |
1958 | if (file->f_mode & FMODE_READ) { |
1959 | iter = __tracing_open(inode, file); | |
1960 | if (IS_ERR(iter)) | |
1961 | ret = PTR_ERR(iter); | |
1962 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) | |
1963 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
1964 | } | |
bc0c38d1 SR |
1965 | return ret; |
1966 | } | |
1967 | ||
e309b41d | 1968 | static void * |
bc0c38d1 SR |
1969 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1970 | { | |
f129e965 | 1971 | struct tracer *t = v; |
bc0c38d1 SR |
1972 | |
1973 | (*pos)++; | |
1974 | ||
1975 | if (t) | |
1976 | t = t->next; | |
1977 | ||
bc0c38d1 SR |
1978 | return t; |
1979 | } | |
1980 | ||
1981 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1982 | { | |
f129e965 | 1983 | struct tracer *t; |
bc0c38d1 SR |
1984 | loff_t l = 0; |
1985 | ||
1986 | mutex_lock(&trace_types_lock); | |
f129e965 | 1987 | for (t = trace_types; t && l < *pos; t = t_next(m, t, &l)) |
bc0c38d1 SR |
1988 | ; |
1989 | ||
1990 | return t; | |
1991 | } | |
1992 | ||
1993 | static void t_stop(struct seq_file *m, void *p) | |
1994 | { | |
1995 | mutex_unlock(&trace_types_lock); | |
1996 | } | |
1997 | ||
1998 | static int t_show(struct seq_file *m, void *v) | |
1999 | { | |
2000 | struct tracer *t = v; | |
2001 | ||
2002 | if (!t) | |
2003 | return 0; | |
2004 | ||
2005 | seq_printf(m, "%s", t->name); | |
2006 | if (t->next) | |
2007 | seq_putc(m, ' '); | |
2008 | else | |
2009 | seq_putc(m, '\n'); | |
2010 | ||
2011 | return 0; | |
2012 | } | |
2013 | ||
2014 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
2015 | .start = t_start, |
2016 | .next = t_next, | |
2017 | .stop = t_stop, | |
2018 | .show = t_show, | |
bc0c38d1 SR |
2019 | }; |
2020 | ||
2021 | static int show_traces_open(struct inode *inode, struct file *file) | |
2022 | { | |
60a11774 SR |
2023 | if (tracing_disabled) |
2024 | return -ENODEV; | |
2025 | ||
f129e965 | 2026 | return seq_open(file, &show_traces_seq_ops); |
bc0c38d1 SR |
2027 | } |
2028 | ||
4acd4d00 SR |
2029 | static ssize_t |
2030 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
2031 | size_t count, loff_t *ppos) | |
2032 | { | |
2033 | return count; | |
2034 | } | |
2035 | ||
5e2336a0 | 2036 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
2037 | .open = tracing_open, |
2038 | .read = seq_read, | |
4acd4d00 | 2039 | .write = tracing_write_stub, |
4bf39a94 IM |
2040 | .llseek = seq_lseek, |
2041 | .release = tracing_release, | |
bc0c38d1 SR |
2042 | }; |
2043 | ||
5e2336a0 | 2044 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
2045 | .open = show_traces_open, |
2046 | .read = seq_read, | |
2047 | .release = seq_release, | |
2048 | }; | |
2049 | ||
36dfe925 IM |
2050 | /* |
2051 | * Only trace on a CPU if the bitmask is set: | |
2052 | */ | |
9e01c1b7 | 2053 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
2054 | |
2055 | /* | |
2056 | * The tracer itself will not take this lock, but still we want | |
2057 | * to provide a consistent cpumask to user-space: | |
2058 | */ | |
2059 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2060 | ||
2061 | /* | |
2062 | * Temporary storage for the character representation of the | |
2063 | * CPU bitmask (and one more byte for the newline): | |
2064 | */ | |
2065 | static char mask_str[NR_CPUS + 1]; | |
2066 | ||
c7078de1 IM |
2067 | static ssize_t |
2068 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2069 | size_t count, loff_t *ppos) | |
2070 | { | |
36dfe925 | 2071 | int len; |
c7078de1 IM |
2072 | |
2073 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2074 | |
9e01c1b7 | 2075 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
2076 | if (count - len < 2) { |
2077 | count = -EINVAL; | |
2078 | goto out_err; | |
2079 | } | |
2080 | len += sprintf(mask_str + len, "\n"); | |
2081 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2082 | ||
2083 | out_err: | |
c7078de1 IM |
2084 | mutex_unlock(&tracing_cpumask_update_lock); |
2085 | ||
2086 | return count; | |
2087 | } | |
2088 | ||
2089 | static ssize_t | |
2090 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2091 | size_t count, loff_t *ppos) | |
2092 | { | |
36dfe925 | 2093 | int err, cpu; |
9e01c1b7 RR |
2094 | cpumask_var_t tracing_cpumask_new; |
2095 | ||
2096 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
2097 | return -ENOMEM; | |
c7078de1 | 2098 | |
9e01c1b7 | 2099 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2100 | if (err) |
36dfe925 IM |
2101 | goto err_unlock; |
2102 | ||
215368e8 LZ |
2103 | mutex_lock(&tracing_cpumask_update_lock); |
2104 | ||
a5e25883 | 2105 | local_irq_disable(); |
92205c23 | 2106 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 2107 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2108 | /* |
2109 | * Increase/decrease the disabled counter if we are | |
2110 | * about to flip a bit in the cpumask: | |
2111 | */ | |
9e01c1b7 RR |
2112 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
2113 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2114 | atomic_inc(&global_trace.data[cpu]->disabled); |
2115 | } | |
9e01c1b7 RR |
2116 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
2117 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
2118 | atomic_dec(&global_trace.data[cpu]->disabled); |
2119 | } | |
2120 | } | |
92205c23 | 2121 | __raw_spin_unlock(&ftrace_max_lock); |
a5e25883 | 2122 | local_irq_enable(); |
36dfe925 | 2123 | |
9e01c1b7 | 2124 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
2125 | |
2126 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2127 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2128 | |
2129 | return count; | |
36dfe925 IM |
2130 | |
2131 | err_unlock: | |
215368e8 | 2132 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
2133 | |
2134 | return err; | |
c7078de1 IM |
2135 | } |
2136 | ||
5e2336a0 | 2137 | static const struct file_operations tracing_cpumask_fops = { |
c7078de1 IM |
2138 | .open = tracing_open_generic, |
2139 | .read = tracing_cpumask_read, | |
2140 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2141 | }; |
2142 | ||
2143 | static ssize_t | |
ee6bce52 | 2144 | tracing_trace_options_read(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
2145 | size_t cnt, loff_t *ppos) |
2146 | { | |
d8e83d26 SR |
2147 | struct tracer_opt *trace_opts; |
2148 | u32 tracer_flags; | |
2149 | int len = 0; | |
bc0c38d1 SR |
2150 | char *buf; |
2151 | int r = 0; | |
d8e83d26 | 2152 | int i; |
adf9f195 | 2153 | |
bc0c38d1 | 2154 | |
c3706f00 | 2155 | /* calculate max size */ |
bc0c38d1 SR |
2156 | for (i = 0; trace_options[i]; i++) { |
2157 | len += strlen(trace_options[i]); | |
5c6a3ae1 | 2158 | len += 3; /* "no" and newline */ |
bc0c38d1 SR |
2159 | } |
2160 | ||
d8e83d26 SR |
2161 | mutex_lock(&trace_types_lock); |
2162 | tracer_flags = current_trace->flags->val; | |
2163 | trace_opts = current_trace->flags->opts; | |
2164 | ||
adf9f195 FW |
2165 | /* |
2166 | * Increase the size with names of options specific | |
2167 | * of the current tracer. | |
2168 | */ | |
2169 | for (i = 0; trace_opts[i].name; i++) { | |
2170 | len += strlen(trace_opts[i].name); | |
5c6a3ae1 | 2171 | len += 3; /* "no" and newline */ |
adf9f195 FW |
2172 | } |
2173 | ||
ff4e9da2 XG |
2174 | /* +1 for \0 */ |
2175 | buf = kmalloc(len + 1, GFP_KERNEL); | |
d8e83d26 SR |
2176 | if (!buf) { |
2177 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 2178 | return -ENOMEM; |
d8e83d26 | 2179 | } |
bc0c38d1 SR |
2180 | |
2181 | for (i = 0; trace_options[i]; i++) { | |
2182 | if (trace_flags & (1 << i)) | |
5c6a3ae1 | 2183 | r += sprintf(buf + r, "%s\n", trace_options[i]); |
bc0c38d1 | 2184 | else |
5c6a3ae1 | 2185 | r += sprintf(buf + r, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2186 | } |
2187 | ||
adf9f195 FW |
2188 | for (i = 0; trace_opts[i].name; i++) { |
2189 | if (tracer_flags & trace_opts[i].bit) | |
5c6a3ae1 | 2190 | r += sprintf(buf + r, "%s\n", |
adf9f195 FW |
2191 | trace_opts[i].name); |
2192 | else | |
5c6a3ae1 | 2193 | r += sprintf(buf + r, "no%s\n", |
adf9f195 FW |
2194 | trace_opts[i].name); |
2195 | } | |
d8e83d26 | 2196 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2197 | |
ff4e9da2 | 2198 | WARN_ON(r >= len + 1); |
bc0c38d1 | 2199 | |
36dfe925 | 2200 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2201 | |
2202 | kfree(buf); | |
bc0c38d1 SR |
2203 | return r; |
2204 | } | |
2205 | ||
adf9f195 FW |
2206 | /* Try to assign a tracer specific option */ |
2207 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2208 | { | |
7770841e | 2209 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 FW |
2210 | struct tracer_opt *opts = NULL; |
2211 | int ret = 0, i = 0; | |
2212 | int len; | |
2213 | ||
7770841e Z |
2214 | for (i = 0; tracer_flags->opts[i].name; i++) { |
2215 | opts = &tracer_flags->opts[i]; | |
adf9f195 FW |
2216 | len = strlen(opts->name); |
2217 | ||
2218 | if (strncmp(cmp, opts->name, len) == 0) { | |
7770841e | 2219 | ret = trace->set_flag(tracer_flags->val, |
adf9f195 FW |
2220 | opts->bit, !neg); |
2221 | break; | |
2222 | } | |
2223 | } | |
2224 | /* Not found */ | |
7770841e | 2225 | if (!tracer_flags->opts[i].name) |
adf9f195 FW |
2226 | return -EINVAL; |
2227 | ||
2228 | /* Refused to handle */ | |
2229 | if (ret) | |
2230 | return ret; | |
2231 | ||
2232 | if (neg) | |
7770841e | 2233 | tracer_flags->val &= ~opts->bit; |
adf9f195 | 2234 | else |
7770841e | 2235 | tracer_flags->val |= opts->bit; |
adf9f195 FW |
2236 | |
2237 | return 0; | |
2238 | } | |
2239 | ||
af4617bd SR |
2240 | static void set_tracer_flags(unsigned int mask, int enabled) |
2241 | { | |
2242 | /* do nothing if flag is already set */ | |
2243 | if (!!(trace_flags & mask) == !!enabled) | |
2244 | return; | |
2245 | ||
2246 | if (enabled) | |
2247 | trace_flags |= mask; | |
2248 | else | |
2249 | trace_flags &= ~mask; | |
af4617bd SR |
2250 | } |
2251 | ||
bc0c38d1 | 2252 | static ssize_t |
ee6bce52 | 2253 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2254 | size_t cnt, loff_t *ppos) |
2255 | { | |
2256 | char buf[64]; | |
2257 | char *cmp = buf; | |
2258 | int neg = 0; | |
adf9f195 | 2259 | int ret; |
bc0c38d1 SR |
2260 | int i; |
2261 | ||
cffae437 SR |
2262 | if (cnt >= sizeof(buf)) |
2263 | return -EINVAL; | |
bc0c38d1 SR |
2264 | |
2265 | if (copy_from_user(&buf, ubuf, cnt)) | |
2266 | return -EFAULT; | |
2267 | ||
2268 | buf[cnt] = 0; | |
2269 | ||
2270 | if (strncmp(buf, "no", 2) == 0) { | |
2271 | neg = 1; | |
2272 | cmp += 2; | |
2273 | } | |
2274 | ||
2275 | for (i = 0; trace_options[i]; i++) { | |
2276 | int len = strlen(trace_options[i]); | |
2277 | ||
2278 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
af4617bd | 2279 | set_tracer_flags(1 << i, !neg); |
bc0c38d1 SR |
2280 | break; |
2281 | } | |
2282 | } | |
adf9f195 FW |
2283 | |
2284 | /* If no option could be set, test the specific tracer options */ | |
2285 | if (!trace_options[i]) { | |
d8e83d26 | 2286 | mutex_lock(&trace_types_lock); |
adf9f195 | 2287 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2288 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2289 | if (ret) |
2290 | return ret; | |
2291 | } | |
bc0c38d1 SR |
2292 | |
2293 | filp->f_pos += cnt; | |
2294 | ||
2295 | return cnt; | |
2296 | } | |
2297 | ||
5e2336a0 | 2298 | static const struct file_operations tracing_iter_fops = { |
c7078de1 | 2299 | .open = tracing_open_generic, |
ee6bce52 SR |
2300 | .read = tracing_trace_options_read, |
2301 | .write = tracing_trace_options_write, | |
bc0c38d1 SR |
2302 | }; |
2303 | ||
7bd2f24c IM |
2304 | static const char readme_msg[] = |
2305 | "tracing mini-HOWTO:\n\n" | |
156f5a78 GL |
2306 | "# mount -t debugfs nodev /sys/kernel/debug\n\n" |
2307 | "# cat /sys/kernel/debug/tracing/available_tracers\n" | |
bc2b6871 | 2308 | "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n" |
156f5a78 | 2309 | "# cat /sys/kernel/debug/tracing/current_tracer\n" |
bc2b6871 | 2310 | "nop\n" |
156f5a78 GL |
2311 | "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n" |
2312 | "# cat /sys/kernel/debug/tracing/current_tracer\n" | |
7bd2f24c | 2313 | "sched_switch\n" |
156f5a78 | 2314 | "# cat /sys/kernel/debug/tracing/trace_options\n" |
7bd2f24c | 2315 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
156f5a78 GL |
2316 | "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n" |
2317 | "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
2318 | "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n" | |
2319 | "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n" | |
7bd2f24c IM |
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 | ||
69abe6a5 AP |
2335 | static ssize_t |
2336 | tracing_saved_cmdlines_read(struct file *file, char __user *ubuf, | |
2337 | size_t cnt, loff_t *ppos) | |
2338 | { | |
2339 | char *buf_comm; | |
2340 | char *file_buf; | |
2341 | char *buf; | |
2342 | int len = 0; | |
2343 | int pid; | |
2344 | int i; | |
2345 | ||
2346 | file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL); | |
2347 | if (!file_buf) | |
2348 | return -ENOMEM; | |
2349 | ||
2350 | buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL); | |
2351 | if (!buf_comm) { | |
2352 | kfree(file_buf); | |
2353 | return -ENOMEM; | |
2354 | } | |
2355 | ||
2356 | buf = file_buf; | |
2357 | ||
2358 | for (i = 0; i < SAVED_CMDLINES; i++) { | |
2359 | int r; | |
2360 | ||
2361 | pid = map_cmdline_to_pid[i]; | |
2362 | if (pid == -1 || pid == NO_CMDLINE_MAP) | |
2363 | continue; | |
2364 | ||
2365 | trace_find_cmdline(pid, buf_comm); | |
2366 | r = sprintf(buf, "%d %s\n", pid, buf_comm); | |
2367 | buf += r; | |
2368 | len += r; | |
2369 | } | |
2370 | ||
2371 | len = simple_read_from_buffer(ubuf, cnt, ppos, | |
2372 | file_buf, len); | |
2373 | ||
2374 | kfree(file_buf); | |
2375 | kfree(buf_comm); | |
2376 | ||
2377 | return len; | |
2378 | } | |
2379 | ||
2380 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
2381 | .open = tracing_open_generic, | |
2382 | .read = tracing_saved_cmdlines_read, | |
2383 | }; | |
2384 | ||
bc0c38d1 SR |
2385 | static ssize_t |
2386 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2387 | size_t cnt, loff_t *ppos) | |
2388 | { | |
bc0c38d1 SR |
2389 | char buf[64]; |
2390 | int r; | |
2391 | ||
9036990d | 2392 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2393 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2394 | } |
2395 | ||
2396 | static ssize_t | |
2397 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2398 | size_t cnt, loff_t *ppos) | |
2399 | { | |
2400 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2401 | char buf[64]; |
5e39841c | 2402 | unsigned long val; |
c6caeeb1 | 2403 | int ret; |
bc0c38d1 | 2404 | |
cffae437 SR |
2405 | if (cnt >= sizeof(buf)) |
2406 | return -EINVAL; | |
bc0c38d1 SR |
2407 | |
2408 | if (copy_from_user(&buf, ubuf, cnt)) | |
2409 | return -EFAULT; | |
2410 | ||
2411 | buf[cnt] = 0; | |
2412 | ||
c6caeeb1 SR |
2413 | ret = strict_strtoul(buf, 10, &val); |
2414 | if (ret < 0) | |
2415 | return ret; | |
bc0c38d1 SR |
2416 | |
2417 | val = !!val; | |
2418 | ||
2419 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2420 | if (tracer_enabled ^ val) { |
2421 | if (val) { | |
bc0c38d1 | 2422 | tracer_enabled = 1; |
9036990d SR |
2423 | if (current_trace->start) |
2424 | current_trace->start(tr); | |
2425 | tracing_start(); | |
2426 | } else { | |
bc0c38d1 | 2427 | tracer_enabled = 0; |
9036990d SR |
2428 | tracing_stop(); |
2429 | if (current_trace->stop) | |
2430 | current_trace->stop(tr); | |
2431 | } | |
bc0c38d1 SR |
2432 | } |
2433 | mutex_unlock(&trace_types_lock); | |
2434 | ||
2435 | filp->f_pos += cnt; | |
2436 | ||
2437 | return cnt; | |
2438 | } | |
2439 | ||
2440 | static ssize_t | |
2441 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2442 | size_t cnt, loff_t *ppos) | |
2443 | { | |
2444 | char buf[max_tracer_type_len+2]; | |
2445 | int r; | |
2446 | ||
2447 | mutex_lock(&trace_types_lock); | |
2448 | if (current_trace) | |
2449 | r = sprintf(buf, "%s\n", current_trace->name); | |
2450 | else | |
2451 | r = sprintf(buf, "\n"); | |
2452 | mutex_unlock(&trace_types_lock); | |
2453 | ||
4bf39a94 | 2454 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2455 | } |
2456 | ||
b6f11df2 ACM |
2457 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2458 | { | |
2459 | tracing_reset_online_cpus(tr); | |
2460 | return t->init(tr); | |
2461 | } | |
2462 | ||
73c5162a SR |
2463 | static int tracing_resize_ring_buffer(unsigned long size) |
2464 | { | |
2465 | int ret; | |
2466 | ||
2467 | /* | |
2468 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
2469 | * we use the size that was given, and we can forget about |
2470 | * expanding it later. | |
73c5162a SR |
2471 | */ |
2472 | ring_buffer_expanded = 1; | |
2473 | ||
2474 | ret = ring_buffer_resize(global_trace.buffer, size); | |
2475 | if (ret < 0) | |
2476 | return ret; | |
2477 | ||
2478 | ret = ring_buffer_resize(max_tr.buffer, size); | |
2479 | if (ret < 0) { | |
2480 | int r; | |
2481 | ||
2482 | r = ring_buffer_resize(global_trace.buffer, | |
2483 | global_trace.entries); | |
2484 | if (r < 0) { | |
a123c52b SR |
2485 | /* |
2486 | * AARGH! We are left with different | |
2487 | * size max buffer!!!! | |
2488 | * The max buffer is our "snapshot" buffer. | |
2489 | * When a tracer needs a snapshot (one of the | |
2490 | * latency tracers), it swaps the max buffer | |
2491 | * with the saved snap shot. We succeeded to | |
2492 | * update the size of the main buffer, but failed to | |
2493 | * update the size of the max buffer. But when we tried | |
2494 | * to reset the main buffer to the original size, we | |
2495 | * failed there too. This is very unlikely to | |
2496 | * happen, but if it does, warn and kill all | |
2497 | * tracing. | |
2498 | */ | |
73c5162a SR |
2499 | WARN_ON(1); |
2500 | tracing_disabled = 1; | |
2501 | } | |
2502 | return ret; | |
2503 | } | |
2504 | ||
2505 | global_trace.entries = size; | |
2506 | ||
2507 | return ret; | |
2508 | } | |
2509 | ||
1852fcce SR |
2510 | /** |
2511 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
2512 | * | |
2513 | * To save on memory when the tracing is never used on a system with it | |
2514 | * configured in. The ring buffers are set to a minimum size. But once | |
2515 | * a user starts to use the tracing facility, then they need to grow | |
2516 | * to their default size. | |
2517 | * | |
2518 | * This function is to be called when a tracer is about to be used. | |
2519 | */ | |
2520 | int tracing_update_buffers(void) | |
2521 | { | |
2522 | int ret = 0; | |
2523 | ||
1027fcb2 | 2524 | mutex_lock(&trace_types_lock); |
1852fcce SR |
2525 | if (!ring_buffer_expanded) |
2526 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
1027fcb2 | 2527 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
2528 | |
2529 | return ret; | |
2530 | } | |
2531 | ||
577b785f SR |
2532 | struct trace_option_dentry; |
2533 | ||
2534 | static struct trace_option_dentry * | |
2535 | create_trace_option_files(struct tracer *tracer); | |
2536 | ||
2537 | static void | |
2538 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2539 | ||
b2821ae6 | 2540 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2541 | { |
577b785f | 2542 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2543 | struct trace_array *tr = &global_trace; |
2544 | struct tracer *t; | |
d9e54076 | 2545 | int ret = 0; |
bc0c38d1 | 2546 | |
1027fcb2 SR |
2547 | mutex_lock(&trace_types_lock); |
2548 | ||
73c5162a SR |
2549 | if (!ring_buffer_expanded) { |
2550 | ret = tracing_resize_ring_buffer(trace_buf_size); | |
2551 | if (ret < 0) | |
59f586db | 2552 | goto out; |
73c5162a SR |
2553 | ret = 0; |
2554 | } | |
2555 | ||
bc0c38d1 SR |
2556 | for (t = trace_types; t; t = t->next) { |
2557 | if (strcmp(t->name, buf) == 0) | |
2558 | break; | |
2559 | } | |
c2931e05 FW |
2560 | if (!t) { |
2561 | ret = -EINVAL; | |
2562 | goto out; | |
2563 | } | |
2564 | if (t == current_trace) | |
bc0c38d1 SR |
2565 | goto out; |
2566 | ||
9f029e83 | 2567 | trace_branch_disable(); |
bc0c38d1 SR |
2568 | if (current_trace && current_trace->reset) |
2569 | current_trace->reset(tr); | |
2570 | ||
577b785f SR |
2571 | destroy_trace_option_files(topts); |
2572 | ||
bc0c38d1 | 2573 | current_trace = t; |
577b785f SR |
2574 | |
2575 | topts = create_trace_option_files(current_trace); | |
2576 | ||
1c80025a | 2577 | if (t->init) { |
b6f11df2 | 2578 | ret = tracer_init(t, tr); |
1c80025a FW |
2579 | if (ret) |
2580 | goto out; | |
2581 | } | |
bc0c38d1 | 2582 | |
9f029e83 | 2583 | trace_branch_enable(tr); |
bc0c38d1 SR |
2584 | out: |
2585 | mutex_unlock(&trace_types_lock); | |
2586 | ||
d9e54076 PZ |
2587 | return ret; |
2588 | } | |
2589 | ||
2590 | static ssize_t | |
2591 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2592 | size_t cnt, loff_t *ppos) | |
2593 | { | |
2594 | char buf[max_tracer_type_len+1]; | |
2595 | int i; | |
2596 | size_t ret; | |
e6e7a65a FW |
2597 | int err; |
2598 | ||
2599 | ret = cnt; | |
d9e54076 PZ |
2600 | |
2601 | if (cnt > max_tracer_type_len) | |
2602 | cnt = max_tracer_type_len; | |
2603 | ||
2604 | if (copy_from_user(&buf, ubuf, cnt)) | |
2605 | return -EFAULT; | |
2606 | ||
2607 | buf[cnt] = 0; | |
2608 | ||
2609 | /* strip ending whitespace. */ | |
2610 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2611 | buf[i] = 0; | |
2612 | ||
e6e7a65a FW |
2613 | err = tracing_set_tracer(buf); |
2614 | if (err) | |
2615 | return err; | |
d9e54076 | 2616 | |
e6e7a65a | 2617 | filp->f_pos += ret; |
bc0c38d1 | 2618 | |
c2931e05 | 2619 | return ret; |
bc0c38d1 SR |
2620 | } |
2621 | ||
2622 | static ssize_t | |
2623 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2624 | size_t cnt, loff_t *ppos) | |
2625 | { | |
2626 | unsigned long *ptr = filp->private_data; | |
2627 | char buf[64]; | |
2628 | int r; | |
2629 | ||
cffae437 | 2630 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2631 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2632 | if (r > sizeof(buf)) |
2633 | r = sizeof(buf); | |
4bf39a94 | 2634 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2635 | } |
2636 | ||
2637 | static ssize_t | |
2638 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2639 | size_t cnt, loff_t *ppos) | |
2640 | { | |
5e39841c | 2641 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2642 | char buf[64]; |
5e39841c | 2643 | unsigned long val; |
c6caeeb1 | 2644 | int ret; |
bc0c38d1 | 2645 | |
cffae437 SR |
2646 | if (cnt >= sizeof(buf)) |
2647 | return -EINVAL; | |
bc0c38d1 SR |
2648 | |
2649 | if (copy_from_user(&buf, ubuf, cnt)) | |
2650 | return -EFAULT; | |
2651 | ||
2652 | buf[cnt] = 0; | |
2653 | ||
c6caeeb1 SR |
2654 | ret = strict_strtoul(buf, 10, &val); |
2655 | if (ret < 0) | |
2656 | return ret; | |
bc0c38d1 SR |
2657 | |
2658 | *ptr = val * 1000; | |
2659 | ||
2660 | return cnt; | |
2661 | } | |
2662 | ||
b3806b43 SR |
2663 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2664 | { | |
b04cc6b1 | 2665 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2666 | struct trace_iterator *iter; |
b04cc6b1 | 2667 | int ret = 0; |
b3806b43 SR |
2668 | |
2669 | if (tracing_disabled) | |
2670 | return -ENODEV; | |
2671 | ||
b04cc6b1 FW |
2672 | mutex_lock(&trace_types_lock); |
2673 | ||
2674 | /* We only allow one reader per cpu */ | |
2675 | if (cpu_file == TRACE_PIPE_ALL_CPU) { | |
2676 | if (!cpumask_empty(tracing_reader_cpumask)) { | |
2677 | ret = -EBUSY; | |
2678 | goto out; | |
2679 | } | |
2680 | cpumask_setall(tracing_reader_cpumask); | |
2681 | } else { | |
2682 | if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask)) | |
2683 | cpumask_set_cpu(cpu_file, tracing_reader_cpumask); | |
2684 | else { | |
2685 | ret = -EBUSY; | |
2686 | goto out; | |
2687 | } | |
b3806b43 SR |
2688 | } |
2689 | ||
2690 | /* create a buffer to store the information to pass to userspace */ | |
2691 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2692 | if (!iter) { |
2693 | ret = -ENOMEM; | |
2694 | goto out; | |
2695 | } | |
b3806b43 | 2696 | |
d7350c3f FW |
2697 | /* |
2698 | * We make a copy of the current tracer to avoid concurrent | |
2699 | * changes on it while we are reading. | |
2700 | */ | |
2701 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
2702 | if (!iter->trace) { | |
2703 | ret = -ENOMEM; | |
2704 | goto fail; | |
2705 | } | |
2706 | if (current_trace) | |
2707 | *iter->trace = *current_trace; | |
2708 | ||
4462344e | 2709 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 2710 | ret = -ENOMEM; |
d7350c3f | 2711 | goto fail; |
4462344e RR |
2712 | } |
2713 | ||
a309720c | 2714 | /* trace pipe does not show start of buffer */ |
4462344e | 2715 | cpumask_setall(iter->started); |
a309720c | 2716 | |
112f38a7 SR |
2717 | if (trace_flags & TRACE_ITER_LATENCY_FMT) |
2718 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2719 | ||
b04cc6b1 | 2720 | iter->cpu_file = cpu_file; |
b3806b43 | 2721 | iter->tr = &global_trace; |
d7350c3f | 2722 | mutex_init(&iter->mutex); |
b3806b43 SR |
2723 | filp->private_data = iter; |
2724 | ||
107bad8b SR |
2725 | if (iter->trace->pipe_open) |
2726 | iter->trace->pipe_open(iter); | |
107bad8b | 2727 | |
b04cc6b1 FW |
2728 | out: |
2729 | mutex_unlock(&trace_types_lock); | |
2730 | return ret; | |
d7350c3f FW |
2731 | |
2732 | fail: | |
2733 | kfree(iter->trace); | |
2734 | kfree(iter); | |
2735 | mutex_unlock(&trace_types_lock); | |
2736 | return ret; | |
b3806b43 SR |
2737 | } |
2738 | ||
2739 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2740 | { | |
2741 | struct trace_iterator *iter = file->private_data; | |
2742 | ||
b04cc6b1 FW |
2743 | mutex_lock(&trace_types_lock); |
2744 | ||
2745 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) | |
2746 | cpumask_clear(tracing_reader_cpumask); | |
2747 | else | |
2748 | cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); | |
2749 | ||
2750 | mutex_unlock(&trace_types_lock); | |
2751 | ||
4462344e | 2752 | free_cpumask_var(iter->started); |
d7350c3f FW |
2753 | mutex_destroy(&iter->mutex); |
2754 | kfree(iter->trace); | |
b3806b43 | 2755 | kfree(iter); |
b3806b43 SR |
2756 | |
2757 | return 0; | |
2758 | } | |
2759 | ||
2a2cc8f7 SSP |
2760 | static unsigned int |
2761 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2762 | { | |
2763 | struct trace_iterator *iter = filp->private_data; | |
2764 | ||
2765 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2766 | /* | |
2767 | * Always select as readable when in blocking mode | |
2768 | */ | |
2769 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2770 | } else { |
2a2cc8f7 SSP |
2771 | if (!trace_empty(iter)) |
2772 | return POLLIN | POLLRDNORM; | |
2773 | poll_wait(filp, &trace_wait, poll_table); | |
2774 | if (!trace_empty(iter)) | |
2775 | return POLLIN | POLLRDNORM; | |
2776 | ||
2777 | return 0; | |
2778 | } | |
2779 | } | |
2780 | ||
6eaaa5d5 FW |
2781 | |
2782 | void default_wait_pipe(struct trace_iterator *iter) | |
2783 | { | |
2784 | DEFINE_WAIT(wait); | |
2785 | ||
2786 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
2787 | ||
2788 | if (trace_empty(iter)) | |
2789 | schedule(); | |
2790 | ||
2791 | finish_wait(&trace_wait, &wait); | |
2792 | } | |
2793 | ||
2794 | /* | |
2795 | * This is a make-shift waitqueue. | |
2796 | * A tracer might use this callback on some rare cases: | |
2797 | * | |
2798 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
2799 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
2800 | * 2) the function tracers, trace all functions, we don't want | |
2801 | * the overhead of calling wake_up and friends | |
2802 | * (and tracing them too) | |
2803 | * | |
2804 | * Anyway, this is really very primitive wakeup. | |
2805 | */ | |
2806 | void poll_wait_pipe(struct trace_iterator *iter) | |
2807 | { | |
2808 | set_current_state(TASK_INTERRUPTIBLE); | |
2809 | /* sleep for 100 msecs, and try again. */ | |
2810 | schedule_timeout(HZ / 10); | |
2811 | } | |
2812 | ||
ff98781b EGM |
2813 | /* Must be called with trace_types_lock mutex held. */ |
2814 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
2815 | { |
2816 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 2817 | |
b3806b43 | 2818 | while (trace_empty(iter)) { |
2dc8f095 | 2819 | |
107bad8b | 2820 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 2821 | return -EAGAIN; |
107bad8b | 2822 | } |
2dc8f095 | 2823 | |
d7350c3f | 2824 | mutex_unlock(&iter->mutex); |
107bad8b | 2825 | |
6eaaa5d5 | 2826 | iter->trace->wait_pipe(iter); |
b3806b43 | 2827 | |
d7350c3f | 2828 | mutex_lock(&iter->mutex); |
107bad8b | 2829 | |
6eaaa5d5 | 2830 | if (signal_pending(current)) |
ff98781b | 2831 | return -EINTR; |
b3806b43 SR |
2832 | |
2833 | /* | |
2834 | * We block until we read something and tracing is disabled. | |
2835 | * We still block if tracing is disabled, but we have never | |
2836 | * read anything. This allows a user to cat this file, and | |
2837 | * then enable tracing. But after we have read something, | |
2838 | * we give an EOF when tracing is again disabled. | |
2839 | * | |
2840 | * iter->pos will be 0 if we haven't read anything. | |
2841 | */ | |
2842 | if (!tracer_enabled && iter->pos) | |
2843 | break; | |
b3806b43 SR |
2844 | } |
2845 | ||
ff98781b EGM |
2846 | return 1; |
2847 | } | |
2848 | ||
2849 | /* | |
2850 | * Consumer reader. | |
2851 | */ | |
2852 | static ssize_t | |
2853 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2854 | size_t cnt, loff_t *ppos) | |
2855 | { | |
2856 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 2857 | static struct tracer *old_tracer; |
ff98781b EGM |
2858 | ssize_t sret; |
2859 | ||
2860 | /* return any leftover data */ | |
2861 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
2862 | if (sret != -EBUSY) | |
2863 | return sret; | |
2864 | ||
f9520750 | 2865 | trace_seq_init(&iter->seq); |
ff98781b | 2866 | |
d7350c3f | 2867 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 2868 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2869 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2870 | old_tracer = current_trace; | |
2871 | *iter->trace = *current_trace; | |
2872 | } | |
2873 | mutex_unlock(&trace_types_lock); | |
2874 | ||
2875 | /* | |
2876 | * Avoid more than one consumer on a single file descriptor | |
2877 | * This is just a matter of traces coherency, the ring buffer itself | |
2878 | * is protected. | |
2879 | */ | |
2880 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
2881 | if (iter->trace->read) { |
2882 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
2883 | if (sret) | |
2884 | goto out; | |
2885 | } | |
2886 | ||
2887 | waitagain: | |
2888 | sret = tracing_wait_pipe(filp); | |
2889 | if (sret <= 0) | |
2890 | goto out; | |
2891 | ||
b3806b43 | 2892 | /* stop when tracing is finished */ |
ff98781b EGM |
2893 | if (trace_empty(iter)) { |
2894 | sret = 0; | |
107bad8b | 2895 | goto out; |
ff98781b | 2896 | } |
b3806b43 SR |
2897 | |
2898 | if (cnt >= PAGE_SIZE) | |
2899 | cnt = PAGE_SIZE - 1; | |
2900 | ||
53d0aa77 | 2901 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
2902 | memset(&iter->seq, 0, |
2903 | sizeof(struct trace_iterator) - | |
2904 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 2905 | iter->pos = -1; |
b3806b43 | 2906 | |
4f535968 | 2907 | trace_event_read_lock(); |
088b1e42 | 2908 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 2909 | enum print_line_t ret; |
088b1e42 SR |
2910 | int len = iter->seq.len; |
2911 | ||
f9896bf3 | 2912 | ret = print_trace_line(iter); |
2c4f035f | 2913 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
2914 | /* don't print partial lines */ |
2915 | iter->seq.len = len; | |
b3806b43 | 2916 | break; |
088b1e42 | 2917 | } |
b91facc3 FW |
2918 | if (ret != TRACE_TYPE_NO_CONSUME) |
2919 | trace_consume(iter); | |
b3806b43 SR |
2920 | |
2921 | if (iter->seq.len >= cnt) | |
2922 | break; | |
b3806b43 | 2923 | } |
4f535968 | 2924 | trace_event_read_unlock(); |
b3806b43 | 2925 | |
b3806b43 | 2926 | /* Now copy what we have to the user */ |
6c6c2796 PP |
2927 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2928 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 2929 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
2930 | |
2931 | /* | |
2932 | * If there was nothing to send to user, inspite of consuming trace | |
2933 | * entries, go back to wait for more entries. | |
2934 | */ | |
6c6c2796 | 2935 | if (sret == -EBUSY) |
9ff4b974 | 2936 | goto waitagain; |
b3806b43 | 2937 | |
107bad8b | 2938 | out: |
d7350c3f | 2939 | mutex_unlock(&iter->mutex); |
107bad8b | 2940 | |
6c6c2796 | 2941 | return sret; |
b3806b43 SR |
2942 | } |
2943 | ||
3c56819b EGM |
2944 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
2945 | struct pipe_buffer *buf) | |
2946 | { | |
2947 | __free_page(buf->page); | |
2948 | } | |
2949 | ||
2950 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
2951 | unsigned int idx) | |
2952 | { | |
2953 | __free_page(spd->pages[idx]); | |
2954 | } | |
2955 | ||
2956 | static struct pipe_buf_operations tracing_pipe_buf_ops = { | |
34cd4998 SR |
2957 | .can_merge = 0, |
2958 | .map = generic_pipe_buf_map, | |
2959 | .unmap = generic_pipe_buf_unmap, | |
2960 | .confirm = generic_pipe_buf_confirm, | |
2961 | .release = tracing_pipe_buf_release, | |
2962 | .steal = generic_pipe_buf_steal, | |
2963 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
2964 | }; |
2965 | ||
34cd4998 | 2966 | static size_t |
fa7c7f6e | 2967 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
2968 | { |
2969 | size_t count; | |
2970 | int ret; | |
2971 | ||
2972 | /* Seq buffer is page-sized, exactly what we need. */ | |
2973 | for (;;) { | |
2974 | count = iter->seq.len; | |
2975 | ret = print_trace_line(iter); | |
2976 | count = iter->seq.len - count; | |
2977 | if (rem < count) { | |
2978 | rem = 0; | |
2979 | iter->seq.len -= count; | |
2980 | break; | |
2981 | } | |
2982 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
2983 | iter->seq.len -= count; | |
2984 | break; | |
2985 | } | |
2986 | ||
74e7ff8c LJ |
2987 | if (ret != TRACE_TYPE_NO_CONSUME) |
2988 | trace_consume(iter); | |
34cd4998 SR |
2989 | rem -= count; |
2990 | if (!find_next_entry_inc(iter)) { | |
2991 | rem = 0; | |
2992 | iter->ent = NULL; | |
2993 | break; | |
2994 | } | |
2995 | } | |
2996 | ||
2997 | return rem; | |
2998 | } | |
2999 | ||
3c56819b EGM |
3000 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
3001 | loff_t *ppos, | |
3002 | struct pipe_inode_info *pipe, | |
3003 | size_t len, | |
3004 | unsigned int flags) | |
3005 | { | |
3006 | struct page *pages[PIPE_BUFFERS]; | |
3007 | struct partial_page partial[PIPE_BUFFERS]; | |
3008 | struct trace_iterator *iter = filp->private_data; | |
3009 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
3010 | .pages = pages, |
3011 | .partial = partial, | |
3012 | .nr_pages = 0, /* This gets updated below. */ | |
3013 | .flags = flags, | |
3014 | .ops = &tracing_pipe_buf_ops, | |
3015 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 3016 | }; |
d7350c3f | 3017 | static struct tracer *old_tracer; |
3c56819b | 3018 | ssize_t ret; |
34cd4998 | 3019 | size_t rem; |
3c56819b EGM |
3020 | unsigned int i; |
3021 | ||
d7350c3f | 3022 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 3023 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
3024 | if (unlikely(old_tracer != current_trace && current_trace)) { |
3025 | old_tracer = current_trace; | |
3026 | *iter->trace = *current_trace; | |
3027 | } | |
3028 | mutex_unlock(&trace_types_lock); | |
3029 | ||
3030 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
3031 | |
3032 | if (iter->trace->splice_read) { | |
3033 | ret = iter->trace->splice_read(iter, filp, | |
3034 | ppos, pipe, len, flags); | |
3035 | if (ret) | |
34cd4998 | 3036 | goto out_err; |
3c56819b EGM |
3037 | } |
3038 | ||
3039 | ret = tracing_wait_pipe(filp); | |
3040 | if (ret <= 0) | |
34cd4998 | 3041 | goto out_err; |
3c56819b EGM |
3042 | |
3043 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
3044 | ret = -EFAULT; | |
34cd4998 | 3045 | goto out_err; |
3c56819b EGM |
3046 | } |
3047 | ||
4f535968 LJ |
3048 | trace_event_read_lock(); |
3049 | ||
3c56819b EGM |
3050 | /* Fill as many pages as possible. */ |
3051 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
3052 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
3053 | if (!pages[i]) |
3054 | break; | |
3c56819b | 3055 | |
fa7c7f6e | 3056 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
3057 | |
3058 | /* Copy the data into the page, so we can start over. */ | |
3059 | ret = trace_seq_to_buffer(&iter->seq, | |
3060 | page_address(pages[i]), | |
3061 | iter->seq.len); | |
3062 | if (ret < 0) { | |
3063 | __free_page(pages[i]); | |
3064 | break; | |
3065 | } | |
3066 | partial[i].offset = 0; | |
3067 | partial[i].len = iter->seq.len; | |
3068 | ||
f9520750 | 3069 | trace_seq_init(&iter->seq); |
3c56819b EGM |
3070 | } |
3071 | ||
4f535968 | 3072 | trace_event_read_unlock(); |
d7350c3f | 3073 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3074 | |
3075 | spd.nr_pages = i; | |
3076 | ||
3077 | return splice_to_pipe(pipe, &spd); | |
3078 | ||
34cd4998 | 3079 | out_err: |
d7350c3f | 3080 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
3081 | |
3082 | return ret; | |
3083 | } | |
3084 | ||
a98a3c3f SR |
3085 | static ssize_t |
3086 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
3087 | size_t cnt, loff_t *ppos) | |
3088 | { | |
3089 | struct trace_array *tr = filp->private_data; | |
db526ca3 | 3090 | char buf[96]; |
a98a3c3f SR |
3091 | int r; |
3092 | ||
db526ca3 SR |
3093 | mutex_lock(&trace_types_lock); |
3094 | if (!ring_buffer_expanded) | |
3095 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
3096 | tr->entries >> 10, | |
3097 | trace_buf_size >> 10); | |
3098 | else | |
3099 | r = sprintf(buf, "%lu\n", tr->entries >> 10); | |
3100 | mutex_unlock(&trace_types_lock); | |
3101 | ||
a98a3c3f SR |
3102 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
3103 | } | |
3104 | ||
3105 | static ssize_t | |
3106 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
3107 | size_t cnt, loff_t *ppos) | |
3108 | { | |
3109 | unsigned long val; | |
3110 | char buf[64]; | |
bf5e6519 | 3111 | int ret, cpu; |
a98a3c3f | 3112 | |
cffae437 SR |
3113 | if (cnt >= sizeof(buf)) |
3114 | return -EINVAL; | |
a98a3c3f SR |
3115 | |
3116 | if (copy_from_user(&buf, ubuf, cnt)) | |
3117 | return -EFAULT; | |
3118 | ||
3119 | buf[cnt] = 0; | |
3120 | ||
c6caeeb1 SR |
3121 | ret = strict_strtoul(buf, 10, &val); |
3122 | if (ret < 0) | |
3123 | return ret; | |
a98a3c3f SR |
3124 | |
3125 | /* must have at least 1 entry */ | |
3126 | if (!val) | |
3127 | return -EINVAL; | |
3128 | ||
3129 | mutex_lock(&trace_types_lock); | |
3130 | ||
c76f0694 | 3131 | tracing_stop(); |
a98a3c3f | 3132 | |
bf5e6519 SR |
3133 | /* disable all cpu buffers */ |
3134 | for_each_tracing_cpu(cpu) { | |
3135 | if (global_trace.data[cpu]) | |
3136 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3137 | if (max_tr.data[cpu]) | |
3138 | atomic_inc(&max_tr.data[cpu]->disabled); | |
3139 | } | |
3140 | ||
1696b2b0 SR |
3141 | /* value is in KB */ |
3142 | val <<= 10; | |
3143 | ||
3928a8a2 | 3144 | if (val != global_trace.entries) { |
73c5162a | 3145 | ret = tracing_resize_ring_buffer(val); |
3928a8a2 SR |
3146 | if (ret < 0) { |
3147 | cnt = ret; | |
3eefae99 SR |
3148 | goto out; |
3149 | } | |
a98a3c3f SR |
3150 | } |
3151 | ||
3152 | filp->f_pos += cnt; | |
3153 | ||
19384c03 SR |
3154 | /* If check pages failed, return ENOMEM */ |
3155 | if (tracing_disabled) | |
3156 | cnt = -ENOMEM; | |
a98a3c3f | 3157 | out: |
bf5e6519 SR |
3158 | for_each_tracing_cpu(cpu) { |
3159 | if (global_trace.data[cpu]) | |
3160 | atomic_dec(&global_trace.data[cpu]->disabled); | |
3161 | if (max_tr.data[cpu]) | |
3162 | atomic_dec(&max_tr.data[cpu]->disabled); | |
3163 | } | |
3164 | ||
c76f0694 | 3165 | tracing_start(); |
a98a3c3f SR |
3166 | max_tr.entries = global_trace.entries; |
3167 | mutex_unlock(&trace_types_lock); | |
3168 | ||
3169 | return cnt; | |
3170 | } | |
3171 | ||
5bf9a1ee PP |
3172 | static int mark_printk(const char *fmt, ...) |
3173 | { | |
3174 | int ret; | |
3175 | va_list args; | |
3176 | va_start(args, fmt); | |
40ce74f1 | 3177 | ret = trace_vprintk(0, fmt, args); |
5bf9a1ee PP |
3178 | va_end(args); |
3179 | return ret; | |
3180 | } | |
3181 | ||
3182 | static ssize_t | |
3183 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
3184 | size_t cnt, loff_t *fpos) | |
3185 | { | |
3186 | char *buf; | |
3187 | char *end; | |
5bf9a1ee | 3188 | |
c76f0694 | 3189 | if (tracing_disabled) |
5bf9a1ee PP |
3190 | return -EINVAL; |
3191 | ||
3192 | if (cnt > TRACE_BUF_SIZE) | |
3193 | cnt = TRACE_BUF_SIZE; | |
3194 | ||
3195 | buf = kmalloc(cnt + 1, GFP_KERNEL); | |
3196 | if (buf == NULL) | |
3197 | return -ENOMEM; | |
3198 | ||
3199 | if (copy_from_user(buf, ubuf, cnt)) { | |
3200 | kfree(buf); | |
3201 | return -EFAULT; | |
3202 | } | |
3203 | ||
3204 | /* Cut from the first nil or newline. */ | |
3205 | buf[cnt] = '\0'; | |
3206 | end = strchr(buf, '\n'); | |
3207 | if (end) | |
3208 | *end = '\0'; | |
3209 | ||
3210 | cnt = mark_printk("%s\n", buf); | |
3211 | kfree(buf); | |
3212 | *fpos += cnt; | |
3213 | ||
3214 | return cnt; | |
3215 | } | |
3216 | ||
5079f326 Z |
3217 | static ssize_t tracing_clock_read(struct file *filp, char __user *ubuf, |
3218 | size_t cnt, loff_t *ppos) | |
3219 | { | |
3220 | char buf[64]; | |
3221 | int bufiter = 0; | |
3222 | int i; | |
3223 | ||
3224 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
3225 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, | |
3226 | "%s%s%s%s", i ? " " : "", | |
3227 | i == trace_clock_id ? "[" : "", trace_clocks[i].name, | |
3228 | i == trace_clock_id ? "]" : ""); | |
3229 | bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, "\n"); | |
3230 | ||
3231 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, bufiter); | |
3232 | } | |
3233 | ||
3234 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
3235 | size_t cnt, loff_t *fpos) | |
3236 | { | |
3237 | char buf[64]; | |
3238 | const char *clockstr; | |
3239 | int i; | |
3240 | ||
3241 | if (cnt >= sizeof(buf)) | |
3242 | return -EINVAL; | |
3243 | ||
3244 | if (copy_from_user(&buf, ubuf, cnt)) | |
3245 | return -EFAULT; | |
3246 | ||
3247 | buf[cnt] = 0; | |
3248 | ||
3249 | clockstr = strstrip(buf); | |
3250 | ||
3251 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { | |
3252 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
3253 | break; | |
3254 | } | |
3255 | if (i == ARRAY_SIZE(trace_clocks)) | |
3256 | return -EINVAL; | |
3257 | ||
3258 | trace_clock_id = i; | |
3259 | ||
3260 | mutex_lock(&trace_types_lock); | |
3261 | ||
3262 | ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func); | |
3263 | if (max_tr.buffer) | |
3264 | ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func); | |
3265 | ||
3266 | mutex_unlock(&trace_types_lock); | |
3267 | ||
3268 | *fpos += cnt; | |
3269 | ||
3270 | return cnt; | |
3271 | } | |
3272 | ||
5e2336a0 | 3273 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
3274 | .open = tracing_open_generic, |
3275 | .read = tracing_max_lat_read, | |
3276 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
3277 | }; |
3278 | ||
5e2336a0 | 3279 | static const struct file_operations tracing_ctrl_fops = { |
4bf39a94 IM |
3280 | .open = tracing_open_generic, |
3281 | .read = tracing_ctrl_read, | |
3282 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
3283 | }; |
3284 | ||
5e2336a0 | 3285 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
3286 | .open = tracing_open_generic, |
3287 | .read = tracing_set_trace_read, | |
3288 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
3289 | }; |
3290 | ||
5e2336a0 | 3291 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 3292 | .open = tracing_open_pipe, |
2a2cc8f7 | 3293 | .poll = tracing_poll_pipe, |
4bf39a94 | 3294 | .read = tracing_read_pipe, |
3c56819b | 3295 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 3296 | .release = tracing_release_pipe, |
b3806b43 SR |
3297 | }; |
3298 | ||
5e2336a0 | 3299 | static const struct file_operations tracing_entries_fops = { |
a98a3c3f SR |
3300 | .open = tracing_open_generic, |
3301 | .read = tracing_entries_read, | |
3302 | .write = tracing_entries_write, | |
3303 | }; | |
3304 | ||
5e2336a0 | 3305 | static const struct file_operations tracing_mark_fops = { |
43a15386 | 3306 | .open = tracing_open_generic, |
5bf9a1ee PP |
3307 | .write = tracing_mark_write, |
3308 | }; | |
3309 | ||
5079f326 Z |
3310 | static const struct file_operations trace_clock_fops = { |
3311 | .open = tracing_open_generic, | |
3312 | .read = tracing_clock_read, | |
3313 | .write = tracing_clock_write, | |
3314 | }; | |
3315 | ||
2cadf913 SR |
3316 | struct ftrace_buffer_info { |
3317 | struct trace_array *tr; | |
3318 | void *spare; | |
3319 | int cpu; | |
3320 | unsigned int read; | |
3321 | }; | |
3322 | ||
3323 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3324 | { | |
3325 | int cpu = (int)(long)inode->i_private; | |
3326 | struct ftrace_buffer_info *info; | |
3327 | ||
3328 | if (tracing_disabled) | |
3329 | return -ENODEV; | |
3330 | ||
3331 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3332 | if (!info) | |
3333 | return -ENOMEM; | |
3334 | ||
3335 | info->tr = &global_trace; | |
3336 | info->cpu = cpu; | |
ddd538f3 | 3337 | info->spare = NULL; |
2cadf913 SR |
3338 | /* Force reading ring buffer for first read */ |
3339 | info->read = (unsigned int)-1; | |
2cadf913 SR |
3340 | |
3341 | filp->private_data = info; | |
3342 | ||
d1e7e02f | 3343 | return nonseekable_open(inode, filp); |
2cadf913 SR |
3344 | } |
3345 | ||
3346 | static ssize_t | |
3347 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3348 | size_t count, loff_t *ppos) | |
3349 | { | |
3350 | struct ftrace_buffer_info *info = filp->private_data; | |
3351 | unsigned int pos; | |
3352 | ssize_t ret; | |
3353 | size_t size; | |
3354 | ||
2dc5d12b SR |
3355 | if (!count) |
3356 | return 0; | |
3357 | ||
ddd538f3 LJ |
3358 | if (!info->spare) |
3359 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3360 | if (!info->spare) | |
3361 | return -ENOMEM; | |
3362 | ||
2cadf913 SR |
3363 | /* Do we have previous read data to read? */ |
3364 | if (info->read < PAGE_SIZE) | |
3365 | goto read; | |
3366 | ||
3367 | info->read = 0; | |
3368 | ||
3369 | ret = ring_buffer_read_page(info->tr->buffer, | |
3370 | &info->spare, | |
3371 | count, | |
3372 | info->cpu, 0); | |
3373 | if (ret < 0) | |
3374 | return 0; | |
3375 | ||
3376 | pos = ring_buffer_page_len(info->spare); | |
3377 | ||
3378 | if (pos < PAGE_SIZE) | |
3379 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3380 | ||
3381 | read: | |
3382 | size = PAGE_SIZE - info->read; | |
3383 | if (size > count) | |
3384 | size = count; | |
3385 | ||
3386 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3387 | if (ret == size) |
2cadf913 | 3388 | return -EFAULT; |
2dc5d12b SR |
3389 | size -= ret; |
3390 | ||
2cadf913 SR |
3391 | *ppos += size; |
3392 | info->read += size; | |
3393 | ||
3394 | return size; | |
3395 | } | |
3396 | ||
3397 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3398 | { | |
3399 | struct ftrace_buffer_info *info = file->private_data; | |
3400 | ||
ddd538f3 LJ |
3401 | if (info->spare) |
3402 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
2cadf913 SR |
3403 | kfree(info); |
3404 | ||
3405 | return 0; | |
3406 | } | |
3407 | ||
3408 | struct buffer_ref { | |
3409 | struct ring_buffer *buffer; | |
3410 | void *page; | |
3411 | int ref; | |
3412 | }; | |
3413 | ||
3414 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3415 | struct pipe_buffer *buf) | |
3416 | { | |
3417 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3418 | ||
3419 | if (--ref->ref) | |
3420 | return; | |
3421 | ||
3422 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3423 | kfree(ref); | |
3424 | buf->private = 0; | |
3425 | } | |
3426 | ||
3427 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3428 | struct pipe_buffer *buf) | |
3429 | { | |
3430 | return 1; | |
3431 | } | |
3432 | ||
3433 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3434 | struct pipe_buffer *buf) | |
3435 | { | |
3436 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3437 | ||
3438 | ref->ref++; | |
3439 | } | |
3440 | ||
3441 | /* Pipe buffer operations for a buffer. */ | |
3442 | static struct pipe_buf_operations buffer_pipe_buf_ops = { | |
3443 | .can_merge = 0, | |
3444 | .map = generic_pipe_buf_map, | |
3445 | .unmap = generic_pipe_buf_unmap, | |
3446 | .confirm = generic_pipe_buf_confirm, | |
3447 | .release = buffer_pipe_buf_release, | |
3448 | .steal = buffer_pipe_buf_steal, | |
3449 | .get = buffer_pipe_buf_get, | |
3450 | }; | |
3451 | ||
3452 | /* | |
3453 | * Callback from splice_to_pipe(), if we need to release some pages | |
3454 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3455 | */ | |
3456 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3457 | { | |
3458 | struct buffer_ref *ref = | |
3459 | (struct buffer_ref *)spd->partial[i].private; | |
3460 | ||
3461 | if (--ref->ref) | |
3462 | return; | |
3463 | ||
3464 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3465 | kfree(ref); | |
3466 | spd->partial[i].private = 0; | |
3467 | } | |
3468 | ||
3469 | static ssize_t | |
3470 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3471 | struct pipe_inode_info *pipe, size_t len, | |
3472 | unsigned int flags) | |
3473 | { | |
3474 | struct ftrace_buffer_info *info = file->private_data; | |
3475 | struct partial_page partial[PIPE_BUFFERS]; | |
3476 | struct page *pages[PIPE_BUFFERS]; | |
3477 | struct splice_pipe_desc spd = { | |
3478 | .pages = pages, | |
3479 | .partial = partial, | |
3480 | .flags = flags, | |
3481 | .ops = &buffer_pipe_buf_ops, | |
3482 | .spd_release = buffer_spd_release, | |
3483 | }; | |
3484 | struct buffer_ref *ref; | |
93459c6c | 3485 | int entries, size, i; |
2cadf913 SR |
3486 | size_t ret; |
3487 | ||
93cfb3c9 LJ |
3488 | if (*ppos & (PAGE_SIZE - 1)) { |
3489 | WARN_ONCE(1, "Ftrace: previous read must page-align\n"); | |
3490 | return -EINVAL; | |
3491 | } | |
3492 | ||
3493 | if (len & (PAGE_SIZE - 1)) { | |
3494 | WARN_ONCE(1, "Ftrace: splice_read should page-align\n"); | |
3495 | if (len < PAGE_SIZE) | |
3496 | return -EINVAL; | |
3497 | len &= PAGE_MASK; | |
3498 | } | |
3499 | ||
93459c6c SR |
3500 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); |
3501 | ||
3502 | for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) { | |
2cadf913 SR |
3503 | struct page *page; |
3504 | int r; | |
3505 | ||
3506 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3507 | if (!ref) | |
3508 | break; | |
3509 | ||
7267fa68 | 3510 | ref->ref = 1; |
2cadf913 SR |
3511 | ref->buffer = info->tr->buffer; |
3512 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3513 | if (!ref->page) { | |
3514 | kfree(ref); | |
3515 | break; | |
3516 | } | |
3517 | ||
3518 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
f2957f1f | 3519 | len, info->cpu, 1); |
2cadf913 SR |
3520 | if (r < 0) { |
3521 | ring_buffer_free_read_page(ref->buffer, | |
3522 | ref->page); | |
3523 | kfree(ref); | |
3524 | break; | |
3525 | } | |
3526 | ||
3527 | /* | |
3528 | * zero out any left over data, this is going to | |
3529 | * user land. | |
3530 | */ | |
3531 | size = ring_buffer_page_len(ref->page); | |
3532 | if (size < PAGE_SIZE) | |
3533 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3534 | ||
3535 | page = virt_to_page(ref->page); | |
3536 | ||
3537 | spd.pages[i] = page; | |
3538 | spd.partial[i].len = PAGE_SIZE; | |
3539 | spd.partial[i].offset = 0; | |
3540 | spd.partial[i].private = (unsigned long)ref; | |
3541 | spd.nr_pages++; | |
93cfb3c9 | 3542 | *ppos += PAGE_SIZE; |
93459c6c SR |
3543 | |
3544 | entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu); | |
2cadf913 SR |
3545 | } |
3546 | ||
3547 | spd.nr_pages = i; | |
3548 | ||
3549 | /* did we read anything? */ | |
3550 | if (!spd.nr_pages) { | |
3551 | if (flags & SPLICE_F_NONBLOCK) | |
3552 | ret = -EAGAIN; | |
3553 | else | |
3554 | ret = 0; | |
3555 | /* TODO: block */ | |
3556 | return ret; | |
3557 | } | |
3558 | ||
3559 | ret = splice_to_pipe(pipe, &spd); | |
3560 | ||
3561 | return ret; | |
3562 | } | |
3563 | ||
3564 | static const struct file_operations tracing_buffers_fops = { | |
3565 | .open = tracing_buffers_open, | |
3566 | .read = tracing_buffers_read, | |
3567 | .release = tracing_buffers_release, | |
3568 | .splice_read = tracing_buffers_splice_read, | |
3569 | .llseek = no_llseek, | |
3570 | }; | |
3571 | ||
c8d77183 SR |
3572 | static ssize_t |
3573 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
3574 | size_t count, loff_t *ppos) | |
3575 | { | |
3576 | unsigned long cpu = (unsigned long)filp->private_data; | |
3577 | struct trace_array *tr = &global_trace; | |
3578 | struct trace_seq *s; | |
3579 | unsigned long cnt; | |
3580 | ||
e4f2d10f | 3581 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 SR |
3582 | if (!s) |
3583 | return ENOMEM; | |
3584 | ||
3585 | trace_seq_init(s); | |
3586 | ||
3587 | cnt = ring_buffer_entries_cpu(tr->buffer, cpu); | |
3588 | trace_seq_printf(s, "entries: %ld\n", cnt); | |
3589 | ||
3590 | cnt = ring_buffer_overrun_cpu(tr->buffer, cpu); | |
3591 | trace_seq_printf(s, "overrun: %ld\n", cnt); | |
3592 | ||
3593 | cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu); | |
3594 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); | |
3595 | ||
c8d77183 SR |
3596 | count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len); |
3597 | ||
3598 | kfree(s); | |
3599 | ||
3600 | return count; | |
3601 | } | |
3602 | ||
3603 | static const struct file_operations tracing_stats_fops = { | |
3604 | .open = tracing_open_generic, | |
3605 | .read = tracing_stats_read, | |
3606 | }; | |
3607 | ||
bc0c38d1 SR |
3608 | #ifdef CONFIG_DYNAMIC_FTRACE |
3609 | ||
b807c3d0 SR |
3610 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3611 | { | |
3612 | return 0; | |
3613 | } | |
3614 | ||
bc0c38d1 | 3615 | static ssize_t |
b807c3d0 | 3616 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3617 | size_t cnt, loff_t *ppos) |
3618 | { | |
a26a2a27 SR |
3619 | static char ftrace_dyn_info_buffer[1024]; |
3620 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3621 | unsigned long *p = filp->private_data; |
b807c3d0 | 3622 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3623 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3624 | int r; |
3625 | ||
b807c3d0 SR |
3626 | mutex_lock(&dyn_info_mutex); |
3627 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3628 | |
a26a2a27 | 3629 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3630 | buf[r++] = '\n'; |
3631 | ||
3632 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3633 | ||
3634 | mutex_unlock(&dyn_info_mutex); | |
3635 | ||
3636 | return r; | |
bc0c38d1 SR |
3637 | } |
3638 | ||
5e2336a0 | 3639 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3640 | .open = tracing_open_generic, |
b807c3d0 | 3641 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3642 | }; |
3643 | #endif | |
3644 | ||
3645 | static struct dentry *d_tracer; | |
3646 | ||
3647 | struct dentry *tracing_init_dentry(void) | |
3648 | { | |
3649 | static int once; | |
3650 | ||
3651 | if (d_tracer) | |
3652 | return d_tracer; | |
3653 | ||
3e1f60b8 FW |
3654 | if (!debugfs_initialized()) |
3655 | return NULL; | |
3656 | ||
bc0c38d1 SR |
3657 | d_tracer = debugfs_create_dir("tracing", NULL); |
3658 | ||
3659 | if (!d_tracer && !once) { | |
3660 | once = 1; | |
3661 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3662 | return NULL; | |
3663 | } | |
3664 | ||
3665 | return d_tracer; | |
3666 | } | |
3667 | ||
b04cc6b1 FW |
3668 | static struct dentry *d_percpu; |
3669 | ||
3670 | struct dentry *tracing_dentry_percpu(void) | |
3671 | { | |
3672 | static int once; | |
3673 | struct dentry *d_tracer; | |
3674 | ||
3675 | if (d_percpu) | |
3676 | return d_percpu; | |
3677 | ||
3678 | d_tracer = tracing_init_dentry(); | |
3679 | ||
3680 | if (!d_tracer) | |
3681 | return NULL; | |
3682 | ||
3683 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
3684 | ||
3685 | if (!d_percpu && !once) { | |
3686 | once = 1; | |
3687 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
3688 | return NULL; | |
3689 | } | |
3690 | ||
3691 | return d_percpu; | |
3692 | } | |
3693 | ||
3694 | static void tracing_init_debugfs_percpu(long cpu) | |
3695 | { | |
3696 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
5452af66 | 3697 | struct dentry *d_cpu; |
8656e7a2 FW |
3698 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ |
3699 | char cpu_dir[7]; | |
b04cc6b1 FW |
3700 | |
3701 | if (cpu > 999 || cpu < 0) | |
3702 | return; | |
3703 | ||
8656e7a2 FW |
3704 | sprintf(cpu_dir, "cpu%ld", cpu); |
3705 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
3706 | if (!d_cpu) { | |
3707 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
3708 | return; | |
3709 | } | |
b04cc6b1 | 3710 | |
8656e7a2 | 3711 | /* per cpu trace_pipe */ |
5452af66 FW |
3712 | trace_create_file("trace_pipe", 0444, d_cpu, |
3713 | (void *) cpu, &tracing_pipe_fops); | |
b04cc6b1 FW |
3714 | |
3715 | /* per cpu trace */ | |
5452af66 FW |
3716 | trace_create_file("trace", 0644, d_cpu, |
3717 | (void *) cpu, &tracing_fops); | |
7f96f93f | 3718 | |
5452af66 FW |
3719 | trace_create_file("trace_pipe_raw", 0444, d_cpu, |
3720 | (void *) cpu, &tracing_buffers_fops); | |
7f96f93f | 3721 | |
c8d77183 SR |
3722 | trace_create_file("stats", 0444, d_cpu, |
3723 | (void *) cpu, &tracing_stats_fops); | |
b04cc6b1 FW |
3724 | } |
3725 | ||
60a11774 SR |
3726 | #ifdef CONFIG_FTRACE_SELFTEST |
3727 | /* Let selftest have access to static functions in this file */ | |
3728 | #include "trace_selftest.c" | |
3729 | #endif | |
3730 | ||
577b785f SR |
3731 | struct trace_option_dentry { |
3732 | struct tracer_opt *opt; | |
3733 | struct tracer_flags *flags; | |
3734 | struct dentry *entry; | |
3735 | }; | |
3736 | ||
3737 | static ssize_t | |
3738 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3739 | loff_t *ppos) | |
3740 | { | |
3741 | struct trace_option_dentry *topt = filp->private_data; | |
3742 | char *buf; | |
3743 | ||
3744 | if (topt->flags->val & topt->opt->bit) | |
3745 | buf = "1\n"; | |
3746 | else | |
3747 | buf = "0\n"; | |
3748 | ||
3749 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3750 | } | |
3751 | ||
3752 | static ssize_t | |
3753 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3754 | loff_t *ppos) | |
3755 | { | |
3756 | struct trace_option_dentry *topt = filp->private_data; | |
3757 | unsigned long val; | |
3758 | char buf[64]; | |
3759 | int ret; | |
3760 | ||
3761 | if (cnt >= sizeof(buf)) | |
3762 | return -EINVAL; | |
3763 | ||
3764 | if (copy_from_user(&buf, ubuf, cnt)) | |
3765 | return -EFAULT; | |
3766 | ||
3767 | buf[cnt] = 0; | |
3768 | ||
3769 | ret = strict_strtoul(buf, 10, &val); | |
3770 | if (ret < 0) | |
3771 | return ret; | |
3772 | ||
3773 | ret = 0; | |
3774 | switch (val) { | |
3775 | case 0: | |
3776 | /* do nothing if already cleared */ | |
3777 | if (!(topt->flags->val & topt->opt->bit)) | |
3778 | break; | |
3779 | ||
3780 | mutex_lock(&trace_types_lock); | |
3781 | if (current_trace->set_flag) | |
3782 | ret = current_trace->set_flag(topt->flags->val, | |
3783 | topt->opt->bit, 0); | |
3784 | mutex_unlock(&trace_types_lock); | |
3785 | if (ret) | |
3786 | return ret; | |
3787 | topt->flags->val &= ~topt->opt->bit; | |
3788 | break; | |
3789 | case 1: | |
3790 | /* do nothing if already set */ | |
3791 | if (topt->flags->val & topt->opt->bit) | |
3792 | break; | |
3793 | ||
3794 | mutex_lock(&trace_types_lock); | |
3795 | if (current_trace->set_flag) | |
3796 | ret = current_trace->set_flag(topt->flags->val, | |
3797 | topt->opt->bit, 1); | |
3798 | mutex_unlock(&trace_types_lock); | |
3799 | if (ret) | |
3800 | return ret; | |
3801 | topt->flags->val |= topt->opt->bit; | |
3802 | break; | |
3803 | ||
3804 | default: | |
3805 | return -EINVAL; | |
3806 | } | |
3807 | ||
3808 | *ppos += cnt; | |
3809 | ||
3810 | return cnt; | |
3811 | } | |
3812 | ||
3813 | ||
3814 | static const struct file_operations trace_options_fops = { | |
3815 | .open = tracing_open_generic, | |
3816 | .read = trace_options_read, | |
3817 | .write = trace_options_write, | |
3818 | }; | |
3819 | ||
a8259075 SR |
3820 | static ssize_t |
3821 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3822 | loff_t *ppos) | |
3823 | { | |
3824 | long index = (long)filp->private_data; | |
3825 | char *buf; | |
3826 | ||
3827 | if (trace_flags & (1 << index)) | |
3828 | buf = "1\n"; | |
3829 | else | |
3830 | buf = "0\n"; | |
3831 | ||
3832 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3833 | } | |
3834 | ||
3835 | static ssize_t | |
3836 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3837 | loff_t *ppos) | |
3838 | { | |
3839 | long index = (long)filp->private_data; | |
3840 | char buf[64]; | |
3841 | unsigned long val; | |
3842 | int ret; | |
3843 | ||
3844 | if (cnt >= sizeof(buf)) | |
3845 | return -EINVAL; | |
3846 | ||
3847 | if (copy_from_user(&buf, ubuf, cnt)) | |
3848 | return -EFAULT; | |
3849 | ||
3850 | buf[cnt] = 0; | |
3851 | ||
3852 | ret = strict_strtoul(buf, 10, &val); | |
3853 | if (ret < 0) | |
3854 | return ret; | |
3855 | ||
3856 | switch (val) { | |
3857 | case 0: | |
3858 | trace_flags &= ~(1 << index); | |
3859 | break; | |
3860 | case 1: | |
3861 | trace_flags |= 1 << index; | |
3862 | break; | |
3863 | ||
3864 | default: | |
3865 | return -EINVAL; | |
3866 | } | |
3867 | ||
3868 | *ppos += cnt; | |
3869 | ||
3870 | return cnt; | |
3871 | } | |
3872 | ||
a8259075 SR |
3873 | static const struct file_operations trace_options_core_fops = { |
3874 | .open = tracing_open_generic, | |
3875 | .read = trace_options_core_read, | |
3876 | .write = trace_options_core_write, | |
3877 | }; | |
3878 | ||
5452af66 FW |
3879 | struct dentry *trace_create_file(const char *name, |
3880 | mode_t mode, | |
3881 | struct dentry *parent, | |
3882 | void *data, | |
3883 | const struct file_operations *fops) | |
3884 | { | |
3885 | struct dentry *ret; | |
3886 | ||
3887 | ret = debugfs_create_file(name, mode, parent, data, fops); | |
3888 | if (!ret) | |
3889 | pr_warning("Could not create debugfs '%s' entry\n", name); | |
3890 | ||
3891 | return ret; | |
3892 | } | |
3893 | ||
3894 | ||
a8259075 SR |
3895 | static struct dentry *trace_options_init_dentry(void) |
3896 | { | |
3897 | struct dentry *d_tracer; | |
3898 | static struct dentry *t_options; | |
3899 | ||
3900 | if (t_options) | |
3901 | return t_options; | |
3902 | ||
3903 | d_tracer = tracing_init_dentry(); | |
3904 | if (!d_tracer) | |
3905 | return NULL; | |
3906 | ||
3907 | t_options = debugfs_create_dir("options", d_tracer); | |
3908 | if (!t_options) { | |
3909 | pr_warning("Could not create debugfs directory 'options'\n"); | |
3910 | return NULL; | |
3911 | } | |
3912 | ||
3913 | return t_options; | |
3914 | } | |
3915 | ||
577b785f SR |
3916 | static void |
3917 | create_trace_option_file(struct trace_option_dentry *topt, | |
3918 | struct tracer_flags *flags, | |
3919 | struct tracer_opt *opt) | |
3920 | { | |
3921 | struct dentry *t_options; | |
577b785f SR |
3922 | |
3923 | t_options = trace_options_init_dentry(); | |
3924 | if (!t_options) | |
3925 | return; | |
3926 | ||
3927 | topt->flags = flags; | |
3928 | topt->opt = opt; | |
3929 | ||
5452af66 | 3930 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
3931 | &trace_options_fops); |
3932 | ||
577b785f SR |
3933 | } |
3934 | ||
3935 | static struct trace_option_dentry * | |
3936 | create_trace_option_files(struct tracer *tracer) | |
3937 | { | |
3938 | struct trace_option_dentry *topts; | |
3939 | struct tracer_flags *flags; | |
3940 | struct tracer_opt *opts; | |
3941 | int cnt; | |
3942 | ||
3943 | if (!tracer) | |
3944 | return NULL; | |
3945 | ||
3946 | flags = tracer->flags; | |
3947 | ||
3948 | if (!flags || !flags->opts) | |
3949 | return NULL; | |
3950 | ||
3951 | opts = flags->opts; | |
3952 | ||
3953 | for (cnt = 0; opts[cnt].name; cnt++) | |
3954 | ; | |
3955 | ||
0cfe8245 | 3956 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
3957 | if (!topts) |
3958 | return NULL; | |
3959 | ||
3960 | for (cnt = 0; opts[cnt].name; cnt++) | |
3961 | create_trace_option_file(&topts[cnt], flags, | |
3962 | &opts[cnt]); | |
3963 | ||
3964 | return topts; | |
3965 | } | |
3966 | ||
3967 | static void | |
3968 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
3969 | { | |
3970 | int cnt; | |
3971 | ||
3972 | if (!topts) | |
3973 | return; | |
3974 | ||
3975 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
3976 | if (topts[cnt].entry) | |
3977 | debugfs_remove(topts[cnt].entry); | |
3978 | } | |
3979 | ||
3980 | kfree(topts); | |
3981 | } | |
3982 | ||
a8259075 SR |
3983 | static struct dentry * |
3984 | create_trace_option_core_file(const char *option, long index) | |
3985 | { | |
3986 | struct dentry *t_options; | |
a8259075 SR |
3987 | |
3988 | t_options = trace_options_init_dentry(); | |
3989 | if (!t_options) | |
3990 | return NULL; | |
3991 | ||
5452af66 | 3992 | return trace_create_file(option, 0644, t_options, (void *)index, |
a8259075 | 3993 | &trace_options_core_fops); |
a8259075 SR |
3994 | } |
3995 | ||
3996 | static __init void create_trace_options_dir(void) | |
3997 | { | |
3998 | struct dentry *t_options; | |
a8259075 SR |
3999 | int i; |
4000 | ||
4001 | t_options = trace_options_init_dentry(); | |
4002 | if (!t_options) | |
4003 | return; | |
4004 | ||
5452af66 FW |
4005 | for (i = 0; trace_options[i]; i++) |
4006 | create_trace_option_core_file(trace_options[i], i); | |
a8259075 SR |
4007 | } |
4008 | ||
b5ad384e | 4009 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
4010 | { |
4011 | struct dentry *d_tracer; | |
b04cc6b1 | 4012 | int cpu; |
bc0c38d1 SR |
4013 | |
4014 | d_tracer = tracing_init_dentry(); | |
4015 | ||
5452af66 FW |
4016 | trace_create_file("tracing_enabled", 0644, d_tracer, |
4017 | &global_trace, &tracing_ctrl_fops); | |
bc0c38d1 | 4018 | |
5452af66 FW |
4019 | trace_create_file("trace_options", 0644, d_tracer, |
4020 | NULL, &tracing_iter_fops); | |
bc0c38d1 | 4021 | |
5452af66 FW |
4022 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
4023 | NULL, &tracing_cpumask_fops); | |
4024 | ||
4025 | trace_create_file("trace", 0644, d_tracer, | |
4026 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); | |
a8259075 | 4027 | |
5452af66 FW |
4028 | trace_create_file("available_tracers", 0444, d_tracer, |
4029 | &global_trace, &show_traces_fops); | |
4030 | ||
339ae5d3 | 4031 | trace_create_file("current_tracer", 0644, d_tracer, |
5452af66 FW |
4032 | &global_trace, &set_tracer_fops); |
4033 | ||
5d4a9dba | 4034 | #ifdef CONFIG_TRACER_MAX_TRACE |
5452af66 FW |
4035 | trace_create_file("tracing_max_latency", 0644, d_tracer, |
4036 | &tracing_max_latency, &tracing_max_lat_fops); | |
4037 | ||
4038 | trace_create_file("tracing_thresh", 0644, d_tracer, | |
4039 | &tracing_thresh, &tracing_max_lat_fops); | |
5d4a9dba | 4040 | #endif |
a8259075 | 4041 | |
339ae5d3 | 4042 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
4043 | NULL, &tracing_readme_fops); |
4044 | ||
4045 | trace_create_file("trace_pipe", 0444, d_tracer, | |
b04cc6b1 | 4046 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); |
5452af66 FW |
4047 | |
4048 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
4049 | &global_trace, &tracing_entries_fops); | |
4050 | ||
4051 | trace_create_file("trace_marker", 0220, d_tracer, | |
4052 | NULL, &tracing_mark_fops); | |
5bf9a1ee | 4053 | |
69abe6a5 AP |
4054 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
4055 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 4056 | |
5079f326 Z |
4057 | trace_create_file("trace_clock", 0644, d_tracer, NULL, |
4058 | &trace_clock_fops); | |
4059 | ||
bc0c38d1 | 4060 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
4061 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
4062 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 4063 | #endif |
d618b3e6 IM |
4064 | #ifdef CONFIG_SYSPROF_TRACER |
4065 | init_tracer_sysprof_debugfs(d_tracer); | |
4066 | #endif | |
b04cc6b1 | 4067 | |
5452af66 FW |
4068 | create_trace_options_dir(); |
4069 | ||
b04cc6b1 FW |
4070 | for_each_tracing_cpu(cpu) |
4071 | tracing_init_debugfs_percpu(cpu); | |
4072 | ||
b5ad384e | 4073 | return 0; |
bc0c38d1 SR |
4074 | } |
4075 | ||
3f5a54e3 SR |
4076 | static int trace_panic_handler(struct notifier_block *this, |
4077 | unsigned long event, void *unused) | |
4078 | { | |
944ac425 SR |
4079 | if (ftrace_dump_on_oops) |
4080 | ftrace_dump(); | |
3f5a54e3 SR |
4081 | return NOTIFY_OK; |
4082 | } | |
4083 | ||
4084 | static struct notifier_block trace_panic_notifier = { | |
4085 | .notifier_call = trace_panic_handler, | |
4086 | .next = NULL, | |
4087 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
4088 | }; | |
4089 | ||
4090 | static int trace_die_handler(struct notifier_block *self, | |
4091 | unsigned long val, | |
4092 | void *data) | |
4093 | { | |
4094 | switch (val) { | |
4095 | case DIE_OOPS: | |
944ac425 SR |
4096 | if (ftrace_dump_on_oops) |
4097 | ftrace_dump(); | |
3f5a54e3 SR |
4098 | break; |
4099 | default: | |
4100 | break; | |
4101 | } | |
4102 | return NOTIFY_OK; | |
4103 | } | |
4104 | ||
4105 | static struct notifier_block trace_die_notifier = { | |
4106 | .notifier_call = trace_die_handler, | |
4107 | .priority = 200 | |
4108 | }; | |
4109 | ||
4110 | /* | |
4111 | * printk is set to max of 1024, we really don't need it that big. | |
4112 | * Nothing should be printing 1000 characters anyway. | |
4113 | */ | |
4114 | #define TRACE_MAX_PRINT 1000 | |
4115 | ||
4116 | /* | |
4117 | * Define here KERN_TRACE so that we have one place to modify | |
4118 | * it if we decide to change what log level the ftrace dump | |
4119 | * should be at. | |
4120 | */ | |
428aee14 | 4121 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
4122 | |
4123 | static void | |
4124 | trace_printk_seq(struct trace_seq *s) | |
4125 | { | |
4126 | /* Probably should print a warning here. */ | |
4127 | if (s->len >= 1000) | |
4128 | s->len = 1000; | |
4129 | ||
4130 | /* should be zero ended, but we are paranoid. */ | |
4131 | s->buffer[s->len] = 0; | |
4132 | ||
4133 | printk(KERN_TRACE "%s", s->buffer); | |
4134 | ||
f9520750 | 4135 | trace_seq_init(s); |
3f5a54e3 SR |
4136 | } |
4137 | ||
cf586b61 | 4138 | static void __ftrace_dump(bool disable_tracing) |
3f5a54e3 | 4139 | { |
cd891ae0 SR |
4140 | static raw_spinlock_t ftrace_dump_lock = |
4141 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
3f5a54e3 SR |
4142 | /* use static because iter can be a bit big for the stack */ |
4143 | static struct trace_iterator iter; | |
cf586b61 | 4144 | unsigned int old_userobj; |
3f5a54e3 | 4145 | static int dump_ran; |
d769041f SR |
4146 | unsigned long flags; |
4147 | int cnt = 0, cpu; | |
3f5a54e3 SR |
4148 | |
4149 | /* only one dump */ | |
cd891ae0 SR |
4150 | local_irq_save(flags); |
4151 | __raw_spin_lock(&ftrace_dump_lock); | |
3f5a54e3 SR |
4152 | if (dump_ran) |
4153 | goto out; | |
4154 | ||
4155 | dump_ran = 1; | |
4156 | ||
0ee6b6cf | 4157 | tracing_off(); |
cf586b61 FW |
4158 | |
4159 | if (disable_tracing) | |
4160 | ftrace_kill(); | |
3f5a54e3 | 4161 | |
d769041f SR |
4162 | for_each_tracing_cpu(cpu) { |
4163 | atomic_inc(&global_trace.data[cpu]->disabled); | |
4164 | } | |
4165 | ||
cf586b61 FW |
4166 | old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; |
4167 | ||
b54d3de9 TE |
4168 | /* don't look at user memory in panic mode */ |
4169 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
4170 | ||
3f5a54e3 SR |
4171 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
4172 | ||
e543ad76 | 4173 | /* Simulate the iterator */ |
3f5a54e3 SR |
4174 | iter.tr = &global_trace; |
4175 | iter.trace = current_trace; | |
e543ad76 | 4176 | iter.cpu_file = TRACE_PIPE_ALL_CPU; |
3f5a54e3 SR |
4177 | |
4178 | /* | |
4179 | * We need to stop all tracing on all CPUS to read the | |
4180 | * the next buffer. This is a bit expensive, but is | |
4181 | * not done often. We fill all what we can read, | |
4182 | * and then release the locks again. | |
4183 | */ | |
4184 | ||
3f5a54e3 SR |
4185 | while (!trace_empty(&iter)) { |
4186 | ||
4187 | if (!cnt) | |
4188 | printk(KERN_TRACE "---------------------------------\n"); | |
4189 | ||
4190 | cnt++; | |
4191 | ||
4192 | /* reset all but tr, trace, and overruns */ | |
4193 | memset(&iter.seq, 0, | |
4194 | sizeof(struct trace_iterator) - | |
4195 | offsetof(struct trace_iterator, seq)); | |
4196 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
4197 | iter.pos = -1; | |
4198 | ||
4199 | if (find_next_entry_inc(&iter) != NULL) { | |
74e7ff8c LJ |
4200 | int ret; |
4201 | ||
4202 | ret = print_trace_line(&iter); | |
4203 | if (ret != TRACE_TYPE_NO_CONSUME) | |
4204 | trace_consume(&iter); | |
3f5a54e3 SR |
4205 | } |
4206 | ||
4207 | trace_printk_seq(&iter.seq); | |
4208 | } | |
4209 | ||
4210 | if (!cnt) | |
4211 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
4212 | else | |
4213 | printk(KERN_TRACE "---------------------------------\n"); | |
4214 | ||
cf586b61 FW |
4215 | /* Re-enable tracing if requested */ |
4216 | if (!disable_tracing) { | |
4217 | trace_flags |= old_userobj; | |
4218 | ||
4219 | for_each_tracing_cpu(cpu) { | |
4220 | atomic_dec(&global_trace.data[cpu]->disabled); | |
4221 | } | |
4222 | tracing_on(); | |
4223 | } | |
4224 | ||
3f5a54e3 | 4225 | out: |
cd891ae0 SR |
4226 | __raw_spin_unlock(&ftrace_dump_lock); |
4227 | local_irq_restore(flags); | |
3f5a54e3 SR |
4228 | } |
4229 | ||
cf586b61 FW |
4230 | /* By default: disable tracing after the dump */ |
4231 | void ftrace_dump(void) | |
4232 | { | |
4233 | __ftrace_dump(true); | |
4234 | } | |
4235 | ||
3928a8a2 | 4236 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 4237 | { |
73c5162a | 4238 | int ring_buf_size; |
4c11d7ae | 4239 | int i; |
9e01c1b7 | 4240 | int ret = -ENOMEM; |
4c11d7ae | 4241 | |
9e01c1b7 RR |
4242 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
4243 | goto out; | |
4244 | ||
4245 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
4246 | goto out_free_buffer_mask; | |
4c11d7ae | 4247 | |
b04cc6b1 FW |
4248 | if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) |
4249 | goto out_free_tracing_cpumask; | |
4250 | ||
73c5162a SR |
4251 | /* To save memory, keep the ring buffer size to its minimum */ |
4252 | if (ring_buffer_expanded) | |
4253 | ring_buf_size = trace_buf_size; | |
4254 | else | |
4255 | ring_buf_size = 1; | |
4256 | ||
9e01c1b7 RR |
4257 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
4258 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
b04cc6b1 | 4259 | cpumask_clear(tracing_reader_cpumask); |
9e01c1b7 RR |
4260 | |
4261 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
73c5162a | 4262 | global_trace.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4263 | TRACE_BUFFER_FLAGS); |
4264 | if (!global_trace.buffer) { | |
4265 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
4266 | WARN_ON(1); | |
9e01c1b7 | 4267 | goto out_free_cpumask; |
4c11d7ae | 4268 | } |
3928a8a2 | 4269 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 4270 | |
9e01c1b7 | 4271 | |
4c11d7ae | 4272 | #ifdef CONFIG_TRACER_MAX_TRACE |
73c5162a | 4273 | max_tr.buffer = ring_buffer_alloc(ring_buf_size, |
3928a8a2 SR |
4274 | TRACE_BUFFER_FLAGS); |
4275 | if (!max_tr.buffer) { | |
4276 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
4277 | WARN_ON(1); | |
4278 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 4279 | goto out_free_cpumask; |
4c11d7ae | 4280 | } |
3928a8a2 SR |
4281 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
4282 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 4283 | #endif |
ab46428c | 4284 | |
4c11d7ae | 4285 | /* Allocate the first page for all buffers */ |
ab46428c | 4286 | for_each_tracing_cpu(i) { |
566b0aaf | 4287 | global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 | 4288 | max_tr.data[i] = &per_cpu(max_data, i); |
4c11d7ae | 4289 | } |
bc0c38d1 | 4290 | |
bc0c38d1 SR |
4291 | trace_init_cmdlines(); |
4292 | ||
43a15386 | 4293 | register_tracer(&nop_trace); |
79fb0768 | 4294 | current_trace = &nop_trace; |
b5ad384e FW |
4295 | #ifdef CONFIG_BOOT_TRACER |
4296 | register_tracer(&boot_tracer); | |
b5ad384e | 4297 | #endif |
60a11774 SR |
4298 | /* All seems OK, enable tracing */ |
4299 | tracing_disabled = 0; | |
3928a8a2 | 4300 | |
3f5a54e3 SR |
4301 | atomic_notifier_chain_register(&panic_notifier_list, |
4302 | &trace_panic_notifier); | |
4303 | ||
4304 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe FW |
4305 | |
4306 | return 0; | |
3f5a54e3 | 4307 | |
9e01c1b7 | 4308 | out_free_cpumask: |
b04cc6b1 FW |
4309 | free_cpumask_var(tracing_reader_cpumask); |
4310 | out_free_tracing_cpumask: | |
9e01c1b7 RR |
4311 | free_cpumask_var(tracing_cpumask); |
4312 | out_free_buffer_mask: | |
4313 | free_cpumask_var(tracing_buffer_mask); | |
4314 | out: | |
4315 | return ret; | |
bc0c38d1 | 4316 | } |
b2821ae6 SR |
4317 | |
4318 | __init static int clear_boot_tracer(void) | |
4319 | { | |
4320 | /* | |
4321 | * The default tracer at boot buffer is an init section. | |
4322 | * This function is called in lateinit. If we did not | |
4323 | * find the boot tracer, then clear it out, to prevent | |
4324 | * later registration from accessing the buffer that is | |
4325 | * about to be freed. | |
4326 | */ | |
4327 | if (!default_bootup_tracer) | |
4328 | return 0; | |
4329 | ||
4330 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4331 | default_bootup_tracer); | |
4332 | default_bootup_tracer = NULL; | |
4333 | ||
4334 | return 0; | |
4335 | } | |
4336 | ||
b5ad384e FW |
4337 | early_initcall(tracer_alloc_buffers); |
4338 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4339 | late_initcall(clear_boot_tracer); |