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Commit | Line | Data |
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fb52607a FW |
1 | /* |
2 | * | |
3 | * Function graph tracer. | |
9005f3eb | 4 | * Copyright (c) 2008-2009 Frederic Weisbecker <fweisbec@gmail.com> |
fb52607a FW |
5 | * Mostly borrowed from function tracer which |
6 | * is Copyright (c) Steven Rostedt <srostedt@redhat.com> | |
7 | * | |
8 | */ | |
fb52607a FW |
9 | #include <linux/uaccess.h> |
10 | #include <linux/ftrace.h> | |
be7635e7 | 11 | #include <linux/interrupt.h> |
5a0e3ad6 | 12 | #include <linux/slab.h> |
fb52607a FW |
13 | #include <linux/fs.h> |
14 | ||
15 | #include "trace.h" | |
f0868d1e | 16 | #include "trace_output.h" |
fb52607a | 17 | |
1b2f121c SRRH |
18 | static bool kill_ftrace_graph; |
19 | ||
20 | /** | |
21 | * ftrace_graph_is_dead - returns true if ftrace_graph_stop() was called | |
22 | * | |
23 | * ftrace_graph_stop() is called when a severe error is detected in | |
24 | * the function graph tracing. This function is called by the critical | |
25 | * paths of function graph to keep those paths from doing any more harm. | |
26 | */ | |
27 | bool ftrace_graph_is_dead(void) | |
28 | { | |
29 | return kill_ftrace_graph; | |
30 | } | |
31 | ||
32 | /** | |
33 | * ftrace_graph_stop - set to permanently disable function graph tracincg | |
34 | * | |
35 | * In case of an error int function graph tracing, this is called | |
36 | * to try to keep function graph tracing from causing any more harm. | |
37 | * Usually this is pretty severe and this is called to try to at least | |
38 | * get a warning out to the user. | |
39 | */ | |
40 | void ftrace_graph_stop(void) | |
41 | { | |
42 | kill_ftrace_graph = true; | |
1b2f121c SRRH |
43 | } |
44 | ||
b304d044 SR |
45 | /* When set, irq functions will be ignored */ |
46 | static int ftrace_graph_skip_irqs; | |
47 | ||
be1eca39 | 48 | struct fgraph_cpu_data { |
2fbcdb35 SR |
49 | pid_t last_pid; |
50 | int depth; | |
2bd16212 | 51 | int depth_irq; |
be1eca39 | 52 | int ignore; |
f1c7f517 | 53 | unsigned long enter_funcs[FTRACE_RETFUNC_DEPTH]; |
be1eca39 JO |
54 | }; |
55 | ||
56 | struct fgraph_data { | |
6016ee13 | 57 | struct fgraph_cpu_data __percpu *cpu_data; |
be1eca39 JO |
58 | |
59 | /* Place to preserve last processed entry. */ | |
60 | struct ftrace_graph_ent_entry ent; | |
61 | struct ftrace_graph_ret_entry ret; | |
62 | int failed; | |
63 | int cpu; | |
2fbcdb35 SR |
64 | }; |
65 | ||
287b6e68 | 66 | #define TRACE_GRAPH_INDENT 2 |
fb52607a | 67 | |
8741db53 SR |
68 | static unsigned int max_depth; |
69 | ||
fb52607a | 70 | static struct tracer_opt trace_opts[] = { |
9005f3eb | 71 | /* Display overruns? (for self-debug purpose) */ |
1a056155 FW |
72 | { TRACER_OPT(funcgraph-overrun, TRACE_GRAPH_PRINT_OVERRUN) }, |
73 | /* Display CPU ? */ | |
74 | { TRACER_OPT(funcgraph-cpu, TRACE_GRAPH_PRINT_CPU) }, | |
75 | /* Display Overhead ? */ | |
76 | { TRACER_OPT(funcgraph-overhead, TRACE_GRAPH_PRINT_OVERHEAD) }, | |
11e84acc FW |
77 | /* Display proc name/pid */ |
78 | { TRACER_OPT(funcgraph-proc, TRACE_GRAPH_PRINT_PROC) }, | |
9005f3eb FW |
79 | /* Display duration of execution */ |
80 | { TRACER_OPT(funcgraph-duration, TRACE_GRAPH_PRINT_DURATION) }, | |
81 | /* Display absolute time of an entry */ | |
82 | { TRACER_OPT(funcgraph-abstime, TRACE_GRAPH_PRINT_ABS_TIME) }, | |
2bd16212 JO |
83 | /* Display interrupts */ |
84 | { TRACER_OPT(funcgraph-irqs, TRACE_GRAPH_PRINT_IRQS) }, | |
607e3a29 RE |
85 | /* Display function name after trailing } */ |
86 | { TRACER_OPT(funcgraph-tail, TRACE_GRAPH_PRINT_TAIL) }, | |
55577204 SRRH |
87 | /* Include sleep time (scheduled out) between entry and return */ |
88 | { TRACER_OPT(sleep-time, TRACE_GRAPH_SLEEP_TIME) }, | |
89 | /* Include time within nested functions */ | |
90 | { TRACER_OPT(graph-time, TRACE_GRAPH_GRAPH_TIME) }, | |
fb52607a FW |
91 | { } /* Empty entry */ |
92 | }; | |
93 | ||
94 | static struct tracer_flags tracer_flags = { | |
607e3a29 | 95 | /* Don't display overruns, proc, or tail by default */ |
9005f3eb | 96 | .val = TRACE_GRAPH_PRINT_CPU | TRACE_GRAPH_PRINT_OVERHEAD | |
55577204 SRRH |
97 | TRACE_GRAPH_PRINT_DURATION | TRACE_GRAPH_PRINT_IRQS | |
98 | TRACE_GRAPH_SLEEP_TIME | TRACE_GRAPH_GRAPH_TIME, | |
fb52607a FW |
99 | .opts = trace_opts |
100 | }; | |
101 | ||
1a0799a8 | 102 | static struct trace_array *graph_array; |
9005f3eb | 103 | |
ffeb80fc JO |
104 | /* |
105 | * DURATION column is being also used to display IRQ signs, | |
106 | * following values are used by print_graph_irq and others | |
107 | * to fill in space into DURATION column. | |
108 | */ | |
109 | enum { | |
6fc84ea7 SRRH |
110 | FLAGS_FILL_FULL = 1 << TRACE_GRAPH_PRINT_FILL_SHIFT, |
111 | FLAGS_FILL_START = 2 << TRACE_GRAPH_PRINT_FILL_SHIFT, | |
112 | FLAGS_FILL_END = 3 << TRACE_GRAPH_PRINT_FILL_SHIFT, | |
ffeb80fc JO |
113 | }; |
114 | ||
9d9add34 | 115 | static void |
983f938a SRRH |
116 | print_graph_duration(struct trace_array *tr, unsigned long long duration, |
117 | struct trace_seq *s, u32 flags); | |
fb52607a | 118 | |
712406a6 SR |
119 | /* Add a function return address to the trace stack on thread info.*/ |
120 | int | |
71e308a2 | 121 | ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth, |
9a7c348b | 122 | unsigned long frame_pointer, unsigned long *retp) |
712406a6 | 123 | { |
5d1a03dc | 124 | unsigned long long calltime; |
712406a6 SR |
125 | int index; |
126 | ||
1b2f121c SRRH |
127 | if (unlikely(ftrace_graph_is_dead())) |
128 | return -EBUSY; | |
129 | ||
712406a6 SR |
130 | if (!current->ret_stack) |
131 | return -EBUSY; | |
132 | ||
82310a32 SR |
133 | /* |
134 | * We must make sure the ret_stack is tested before we read | |
135 | * anything else. | |
136 | */ | |
137 | smp_rmb(); | |
138 | ||
712406a6 SR |
139 | /* The return trace stack is full */ |
140 | if (current->curr_ret_stack == FTRACE_RETFUNC_DEPTH - 1) { | |
141 | atomic_inc(¤t->trace_overrun); | |
142 | return -EBUSY; | |
143 | } | |
144 | ||
29ad23b0 NK |
145 | /* |
146 | * The curr_ret_stack is an index to ftrace return stack of | |
147 | * current task. Its value should be in [0, FTRACE_RETFUNC_ | |
148 | * DEPTH) when the function graph tracer is used. To support | |
149 | * filtering out specific functions, it makes the index | |
150 | * negative by subtracting huge value (FTRACE_NOTRACE_DEPTH) | |
151 | * so when it sees a negative index the ftrace will ignore | |
152 | * the record. And the index gets recovered when returning | |
153 | * from the filtered function by adding the FTRACE_NOTRACE_ | |
154 | * DEPTH and then it'll continue to record functions normally. | |
155 | * | |
156 | * The curr_ret_stack is initialized to -1 and get increased | |
157 | * in this function. So it can be less than -1 only if it was | |
158 | * filtered out via ftrace_graph_notrace_addr() which can be | |
8434dc93 | 159 | * set from set_graph_notrace file in tracefs by user. |
29ad23b0 NK |
160 | */ |
161 | if (current->curr_ret_stack < -1) | |
162 | return -EBUSY; | |
163 | ||
5d1a03dc SR |
164 | calltime = trace_clock_local(); |
165 | ||
712406a6 | 166 | index = ++current->curr_ret_stack; |
29ad23b0 NK |
167 | if (ftrace_graph_notrace_addr(func)) |
168 | current->curr_ret_stack -= FTRACE_NOTRACE_DEPTH; | |
712406a6 SR |
169 | barrier(); |
170 | current->ret_stack[index].ret = ret; | |
171 | current->ret_stack[index].func = func; | |
5d1a03dc | 172 | current->ret_stack[index].calltime = calltime; |
a2a16d6a | 173 | current->ret_stack[index].subtime = 0; |
daa460a8 | 174 | #ifdef HAVE_FUNCTION_GRAPH_FP_TEST |
71e308a2 | 175 | current->ret_stack[index].fp = frame_pointer; |
9a7c348b JP |
176 | #endif |
177 | #ifdef HAVE_FUNCTION_GRAPH_RET_ADDR_PTR | |
178 | current->ret_stack[index].retp = retp; | |
daa460a8 | 179 | #endif |
29ad23b0 | 180 | *depth = current->curr_ret_stack; |
712406a6 SR |
181 | |
182 | return 0; | |
183 | } | |
184 | ||
185 | /* Retrieve a function return address to the trace stack on thread info.*/ | |
a2a16d6a | 186 | static void |
71e308a2 SR |
187 | ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret, |
188 | unsigned long frame_pointer) | |
712406a6 SR |
189 | { |
190 | int index; | |
191 | ||
192 | index = current->curr_ret_stack; | |
193 | ||
29ad23b0 NK |
194 | /* |
195 | * A negative index here means that it's just returned from a | |
196 | * notrace'd function. Recover index to get an original | |
197 | * return address. See ftrace_push_return_trace(). | |
198 | * | |
199 | * TODO: Need to check whether the stack gets corrupted. | |
200 | */ | |
201 | if (index < 0) | |
202 | index += FTRACE_NOTRACE_DEPTH; | |
203 | ||
204 | if (unlikely(index < 0 || index >= FTRACE_RETFUNC_DEPTH)) { | |
712406a6 SR |
205 | ftrace_graph_stop(); |
206 | WARN_ON(1); | |
207 | /* Might as well panic, otherwise we have no where to go */ | |
208 | *ret = (unsigned long)panic; | |
209 | return; | |
210 | } | |
211 | ||
e4a744ef | 212 | #ifdef HAVE_FUNCTION_GRAPH_FP_TEST |
71e308a2 SR |
213 | /* |
214 | * The arch may choose to record the frame pointer used | |
215 | * and check it here to make sure that it is what we expect it | |
216 | * to be. If gcc does not set the place holder of the return | |
217 | * address in the frame pointer, and does a copy instead, then | |
218 | * the function graph trace will fail. This test detects this | |
219 | * case. | |
220 | * | |
221 | * Currently, x86_32 with optimize for size (-Os) makes the latest | |
222 | * gcc do the above. | |
781d0624 SR |
223 | * |
224 | * Note, -mfentry does not use frame pointers, and this test | |
225 | * is not needed if CC_USING_FENTRY is set. | |
71e308a2 SR |
226 | */ |
227 | if (unlikely(current->ret_stack[index].fp != frame_pointer)) { | |
228 | ftrace_graph_stop(); | |
229 | WARN(1, "Bad frame pointer: expected %lx, received %lx\n" | |
b375a11a | 230 | " from func %ps return to %lx\n", |
71e308a2 SR |
231 | current->ret_stack[index].fp, |
232 | frame_pointer, | |
233 | (void *)current->ret_stack[index].func, | |
234 | current->ret_stack[index].ret); | |
235 | *ret = (unsigned long)panic; | |
236 | return; | |
237 | } | |
238 | #endif | |
239 | ||
712406a6 SR |
240 | *ret = current->ret_stack[index].ret; |
241 | trace->func = current->ret_stack[index].func; | |
242 | trace->calltime = current->ret_stack[index].calltime; | |
243 | trace->overrun = atomic_read(¤t->trace_overrun); | |
244 | trace->depth = index; | |
712406a6 SR |
245 | } |
246 | ||
247 | /* | |
248 | * Send the trace to the ring-buffer. | |
249 | * @return the original return address. | |
250 | */ | |
71e308a2 | 251 | unsigned long ftrace_return_to_handler(unsigned long frame_pointer) |
712406a6 SR |
252 | { |
253 | struct ftrace_graph_ret trace; | |
254 | unsigned long ret; | |
255 | ||
71e308a2 | 256 | ftrace_pop_return_trace(&trace, &ret, frame_pointer); |
0012693a | 257 | trace.rettime = trace_clock_local(); |
a2a16d6a SR |
258 | barrier(); |
259 | current->curr_ret_stack--; | |
29ad23b0 NK |
260 | /* |
261 | * The curr_ret_stack can be less than -1 only if it was | |
262 | * filtered out and it's about to return from the function. | |
263 | * Recover the index and continue to trace normal functions. | |
264 | */ | |
265 | if (current->curr_ret_stack < -1) { | |
266 | current->curr_ret_stack += FTRACE_NOTRACE_DEPTH; | |
267 | return ret; | |
268 | } | |
712406a6 | 269 | |
03274a3f SRRH |
270 | /* |
271 | * The trace should run after decrementing the ret counter | |
272 | * in case an interrupt were to come in. We don't want to | |
273 | * lose the interrupt if max_depth is set. | |
274 | */ | |
275 | ftrace_graph_return(&trace); | |
276 | ||
712406a6 SR |
277 | if (unlikely(!ret)) { |
278 | ftrace_graph_stop(); | |
279 | WARN_ON(1); | |
280 | /* Might as well panic. What else to do? */ | |
281 | ret = (unsigned long)panic; | |
282 | } | |
283 | ||
284 | return ret; | |
285 | } | |
286 | ||
223918e3 JP |
287 | /** |
288 | * ftrace_graph_ret_addr - convert a potentially modified stack return address | |
289 | * to its original value | |
290 | * | |
291 | * This function can be called by stack unwinding code to convert a found stack | |
292 | * return address ('ret') to its original value, in case the function graph | |
293 | * tracer has modified it to be 'return_to_handler'. If the address hasn't | |
294 | * been modified, the unchanged value of 'ret' is returned. | |
295 | * | |
296 | * 'idx' is a state variable which should be initialized by the caller to zero | |
297 | * before the first call. | |
298 | * | |
299 | * 'retp' is a pointer to the return address on the stack. It's ignored if | |
300 | * the arch doesn't have HAVE_FUNCTION_GRAPH_RET_ADDR_PTR defined. | |
301 | */ | |
302 | #ifdef HAVE_FUNCTION_GRAPH_RET_ADDR_PTR | |
303 | unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx, | |
304 | unsigned long ret, unsigned long *retp) | |
305 | { | |
306 | int index = task->curr_ret_stack; | |
307 | int i; | |
308 | ||
309 | if (ret != (unsigned long)return_to_handler) | |
310 | return ret; | |
311 | ||
312 | if (index < -1) | |
313 | index += FTRACE_NOTRACE_DEPTH; | |
314 | ||
315 | if (index < 0) | |
316 | return ret; | |
317 | ||
318 | for (i = 0; i <= index; i++) | |
319 | if (task->ret_stack[i].retp == retp) | |
320 | return task->ret_stack[i].ret; | |
321 | ||
322 | return ret; | |
323 | } | |
324 | #else /* !HAVE_FUNCTION_GRAPH_RET_ADDR_PTR */ | |
325 | unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx, | |
326 | unsigned long ret, unsigned long *retp) | |
327 | { | |
328 | int task_idx; | |
329 | ||
330 | if (ret != (unsigned long)return_to_handler) | |
331 | return ret; | |
332 | ||
333 | task_idx = task->curr_ret_stack; | |
334 | ||
335 | if (!task->ret_stack || task_idx < *idx) | |
336 | return ret; | |
337 | ||
338 | task_idx -= *idx; | |
339 | (*idx)++; | |
340 | ||
341 | return task->ret_stack[task_idx].ret; | |
342 | } | |
343 | #endif /* HAVE_FUNCTION_GRAPH_RET_ADDR_PTR */ | |
344 | ||
62b915f1 | 345 | int __trace_graph_entry(struct trace_array *tr, |
1a0799a8 FW |
346 | struct ftrace_graph_ent *trace, |
347 | unsigned long flags, | |
348 | int pc) | |
349 | { | |
2425bcb9 | 350 | struct trace_event_call *call = &event_funcgraph_entry; |
1a0799a8 | 351 | struct ring_buffer_event *event; |
12883efb | 352 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
1a0799a8 FW |
353 | struct ftrace_graph_ent_entry *entry; |
354 | ||
e77405ad | 355 | event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_ENT, |
1a0799a8 FW |
356 | sizeof(*entry), flags, pc); |
357 | if (!event) | |
358 | return 0; | |
359 | entry = ring_buffer_event_data(event); | |
360 | entry->graph_ent = *trace; | |
f306cc82 | 361 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 362 | __buffer_unlock_commit(buffer, event); |
1a0799a8 FW |
363 | |
364 | return 1; | |
365 | } | |
366 | ||
b304d044 SR |
367 | static inline int ftrace_graph_ignore_irqs(void) |
368 | { | |
e4a3f541 | 369 | if (!ftrace_graph_skip_irqs || trace_recursion_test(TRACE_IRQ_BIT)) |
b304d044 SR |
370 | return 0; |
371 | ||
372 | return in_irq(); | |
373 | } | |
374 | ||
1a0799a8 FW |
375 | int trace_graph_entry(struct ftrace_graph_ent *trace) |
376 | { | |
377 | struct trace_array *tr = graph_array; | |
378 | struct trace_array_cpu *data; | |
379 | unsigned long flags; | |
380 | long disabled; | |
381 | int ret; | |
382 | int cpu; | |
383 | int pc; | |
384 | ||
345ddcc8 | 385 | if (!ftrace_trace_task(tr)) |
1a0799a8 FW |
386 | return 0; |
387 | ||
ea2c68a0 | 388 | /* trace it when it is-nested-in or is a function enabled. */ |
8741db53 | 389 | if ((!(trace->depth || ftrace_graph_addr(trace->func)) || |
29ad23b0 | 390 | ftrace_graph_ignore_irqs()) || (trace->depth < 0) || |
8741db53 | 391 | (max_depth && trace->depth >= max_depth)) |
1a0799a8 FW |
392 | return 0; |
393 | ||
29ad23b0 NK |
394 | /* |
395 | * Do not trace a function if it's filtered by set_graph_notrace. | |
396 | * Make the index of ret stack negative to indicate that it should | |
397 | * ignore further functions. But it needs its own ret stack entry | |
398 | * to recover the original index in order to continue tracing after | |
399 | * returning from the function. | |
400 | */ | |
401 | if (ftrace_graph_notrace_addr(trace->func)) | |
402 | return 1; | |
403 | ||
7fa8b717 JF |
404 | /* |
405 | * Stop here if tracing_threshold is set. We only write function return | |
406 | * events to the ring buffer. | |
407 | */ | |
408 | if (tracing_thresh) | |
409 | return 1; | |
410 | ||
1a0799a8 FW |
411 | local_irq_save(flags); |
412 | cpu = raw_smp_processor_id(); | |
12883efb | 413 | data = per_cpu_ptr(tr->trace_buffer.data, cpu); |
1a0799a8 FW |
414 | disabled = atomic_inc_return(&data->disabled); |
415 | if (likely(disabled == 1)) { | |
416 | pc = preempt_count(); | |
417 | ret = __trace_graph_entry(tr, trace, flags, pc); | |
418 | } else { | |
419 | ret = 0; | |
420 | } | |
1a0799a8 FW |
421 | |
422 | atomic_dec(&data->disabled); | |
423 | local_irq_restore(flags); | |
424 | ||
425 | return ret; | |
426 | } | |
427 | ||
0a772620 JO |
428 | static void |
429 | __trace_graph_function(struct trace_array *tr, | |
430 | unsigned long ip, unsigned long flags, int pc) | |
431 | { | |
432 | u64 time = trace_clock_local(); | |
433 | struct ftrace_graph_ent ent = { | |
434 | .func = ip, | |
435 | .depth = 0, | |
436 | }; | |
437 | struct ftrace_graph_ret ret = { | |
438 | .func = ip, | |
439 | .depth = 0, | |
440 | .calltime = time, | |
441 | .rettime = time, | |
442 | }; | |
443 | ||
444 | __trace_graph_entry(tr, &ent, flags, pc); | |
445 | __trace_graph_return(tr, &ret, flags, pc); | |
446 | } | |
447 | ||
448 | void | |
449 | trace_graph_function(struct trace_array *tr, | |
450 | unsigned long ip, unsigned long parent_ip, | |
451 | unsigned long flags, int pc) | |
452 | { | |
0a772620 JO |
453 | __trace_graph_function(tr, ip, flags, pc); |
454 | } | |
455 | ||
62b915f1 | 456 | void __trace_graph_return(struct trace_array *tr, |
1a0799a8 FW |
457 | struct ftrace_graph_ret *trace, |
458 | unsigned long flags, | |
459 | int pc) | |
460 | { | |
2425bcb9 | 461 | struct trace_event_call *call = &event_funcgraph_exit; |
1a0799a8 | 462 | struct ring_buffer_event *event; |
12883efb | 463 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
1a0799a8 FW |
464 | struct ftrace_graph_ret_entry *entry; |
465 | ||
e77405ad | 466 | event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_RET, |
1a0799a8 FW |
467 | sizeof(*entry), flags, pc); |
468 | if (!event) | |
469 | return; | |
470 | entry = ring_buffer_event_data(event); | |
471 | entry->ret = *trace; | |
f306cc82 | 472 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 473 | __buffer_unlock_commit(buffer, event); |
1a0799a8 FW |
474 | } |
475 | ||
476 | void trace_graph_return(struct ftrace_graph_ret *trace) | |
477 | { | |
478 | struct trace_array *tr = graph_array; | |
479 | struct trace_array_cpu *data; | |
480 | unsigned long flags; | |
481 | long disabled; | |
482 | int cpu; | |
483 | int pc; | |
484 | ||
485 | local_irq_save(flags); | |
486 | cpu = raw_smp_processor_id(); | |
12883efb | 487 | data = per_cpu_ptr(tr->trace_buffer.data, cpu); |
1a0799a8 FW |
488 | disabled = atomic_inc_return(&data->disabled); |
489 | if (likely(disabled == 1)) { | |
490 | pc = preempt_count(); | |
491 | __trace_graph_return(tr, trace, flags, pc); | |
492 | } | |
1a0799a8 FW |
493 | atomic_dec(&data->disabled); |
494 | local_irq_restore(flags); | |
495 | } | |
496 | ||
24a53652 FW |
497 | void set_graph_array(struct trace_array *tr) |
498 | { | |
499 | graph_array = tr; | |
500 | ||
501 | /* Make graph_array visible before we start tracing */ | |
502 | ||
503 | smp_mb(); | |
504 | } | |
505 | ||
ba1afef6 | 506 | static void trace_graph_thresh_return(struct ftrace_graph_ret *trace) |
0e950173 TB |
507 | { |
508 | if (tracing_thresh && | |
509 | (trace->rettime - trace->calltime < tracing_thresh)) | |
510 | return; | |
511 | else | |
512 | trace_graph_return(trace); | |
513 | } | |
514 | ||
fb52607a FW |
515 | static int graph_trace_init(struct trace_array *tr) |
516 | { | |
1a0799a8 FW |
517 | int ret; |
518 | ||
24a53652 | 519 | set_graph_array(tr); |
0e950173 TB |
520 | if (tracing_thresh) |
521 | ret = register_ftrace_graph(&trace_graph_thresh_return, | |
7fa8b717 | 522 | &trace_graph_entry); |
0e950173 TB |
523 | else |
524 | ret = register_ftrace_graph(&trace_graph_return, | |
525 | &trace_graph_entry); | |
660c7f9b SR |
526 | if (ret) |
527 | return ret; | |
528 | tracing_start_cmdline_record(); | |
529 | ||
530 | return 0; | |
fb52607a FW |
531 | } |
532 | ||
533 | static void graph_trace_reset(struct trace_array *tr) | |
534 | { | |
660c7f9b SR |
535 | tracing_stop_cmdline_record(); |
536 | unregister_ftrace_graph(); | |
fb52607a FW |
537 | } |
538 | ||
ba1afef6 | 539 | static int graph_trace_update_thresh(struct trace_array *tr) |
6508fa76 SF |
540 | { |
541 | graph_trace_reset(tr); | |
542 | return graph_trace_init(tr); | |
543 | } | |
544 | ||
0c9e6f63 | 545 | static int max_bytes_for_cpu; |
1a056155 | 546 | |
9d9add34 | 547 | static void print_graph_cpu(struct trace_seq *s, int cpu) |
1a056155 | 548 | { |
d51090b3 IM |
549 | /* |
550 | * Start with a space character - to make it stand out | |
551 | * to the right a bit when trace output is pasted into | |
552 | * email: | |
553 | */ | |
9d9add34 | 554 | trace_seq_printf(s, " %*d) ", max_bytes_for_cpu, cpu); |
1a056155 FW |
555 | } |
556 | ||
11e84acc FW |
557 | #define TRACE_GRAPH_PROCINFO_LENGTH 14 |
558 | ||
9d9add34 | 559 | static void print_graph_proc(struct trace_seq *s, pid_t pid) |
11e84acc | 560 | { |
4ca53085 | 561 | char comm[TASK_COMM_LEN]; |
11e84acc FW |
562 | /* sign + log10(MAX_INT) + '\0' */ |
563 | char pid_str[11]; | |
4ca53085 | 564 | int spaces = 0; |
4ca53085 SR |
565 | int len; |
566 | int i; | |
11e84acc | 567 | |
4ca53085 | 568 | trace_find_cmdline(pid, comm); |
11e84acc FW |
569 | comm[7] = '\0'; |
570 | sprintf(pid_str, "%d", pid); | |
571 | ||
572 | /* 1 stands for the "-" character */ | |
573 | len = strlen(comm) + strlen(pid_str) + 1; | |
574 | ||
575 | if (len < TRACE_GRAPH_PROCINFO_LENGTH) | |
576 | spaces = TRACE_GRAPH_PROCINFO_LENGTH - len; | |
577 | ||
578 | /* First spaces to align center */ | |
9d9add34 SRRH |
579 | for (i = 0; i < spaces / 2; i++) |
580 | trace_seq_putc(s, ' '); | |
11e84acc | 581 | |
9d9add34 | 582 | trace_seq_printf(s, "%s-%s", comm, pid_str); |
11e84acc FW |
583 | |
584 | /* Last spaces to align center */ | |
9d9add34 SRRH |
585 | for (i = 0; i < spaces - (spaces / 2); i++) |
586 | trace_seq_putc(s, ' '); | |
11e84acc FW |
587 | } |
588 | ||
1a056155 | 589 | |
9d9add34 | 590 | static void print_graph_lat_fmt(struct trace_seq *s, struct trace_entry *entry) |
49ff5903 | 591 | { |
9d9add34 SRRH |
592 | trace_seq_putc(s, ' '); |
593 | trace_print_lat_fmt(s, entry); | |
49ff5903 SR |
594 | } |
595 | ||
287b6e68 | 596 | /* If the pid changed since the last trace, output this event */ |
9d9add34 | 597 | static void |
2fbcdb35 | 598 | verif_pid(struct trace_seq *s, pid_t pid, int cpu, struct fgraph_data *data) |
287b6e68 | 599 | { |
d51090b3 | 600 | pid_t prev_pid; |
9005f3eb | 601 | pid_t *last_pid; |
660c7f9b | 602 | |
2fbcdb35 | 603 | if (!data) |
9d9add34 | 604 | return; |
9005f3eb | 605 | |
be1eca39 | 606 | last_pid = &(per_cpu_ptr(data->cpu_data, cpu)->last_pid); |
9005f3eb FW |
607 | |
608 | if (*last_pid == pid) | |
9d9add34 | 609 | return; |
fb52607a | 610 | |
9005f3eb FW |
611 | prev_pid = *last_pid; |
612 | *last_pid = pid; | |
d51090b3 | 613 | |
9005f3eb | 614 | if (prev_pid == -1) |
9d9add34 | 615 | return; |
d51090b3 IM |
616 | /* |
617 | * Context-switch trace line: | |
618 | ||
619 | ------------------------------------------ | |
620 | | 1) migration/0--1 => sshd-1755 | |
621 | ------------------------------------------ | |
622 | ||
623 | */ | |
9d9add34 SRRH |
624 | trace_seq_puts(s, " ------------------------------------------\n"); |
625 | print_graph_cpu(s, cpu); | |
626 | print_graph_proc(s, prev_pid); | |
627 | trace_seq_puts(s, " => "); | |
628 | print_graph_proc(s, pid); | |
629 | trace_seq_puts(s, "\n ------------------------------------------\n\n"); | |
287b6e68 FW |
630 | } |
631 | ||
b91facc3 FW |
632 | static struct ftrace_graph_ret_entry * |
633 | get_return_for_leaf(struct trace_iterator *iter, | |
83a8df61 FW |
634 | struct ftrace_graph_ent_entry *curr) |
635 | { | |
be1eca39 JO |
636 | struct fgraph_data *data = iter->private; |
637 | struct ring_buffer_iter *ring_iter = NULL; | |
83a8df61 FW |
638 | struct ring_buffer_event *event; |
639 | struct ftrace_graph_ret_entry *next; | |
640 | ||
be1eca39 JO |
641 | /* |
642 | * If the previous output failed to write to the seq buffer, | |
643 | * then we just reuse the data from before. | |
644 | */ | |
645 | if (data && data->failed) { | |
646 | curr = &data->ent; | |
647 | next = &data->ret; | |
648 | } else { | |
83a8df61 | 649 | |
6d158a81 | 650 | ring_iter = trace_buffer_iter(iter, iter->cpu); |
be1eca39 JO |
651 | |
652 | /* First peek to compare current entry and the next one */ | |
653 | if (ring_iter) | |
654 | event = ring_buffer_iter_peek(ring_iter, NULL); | |
655 | else { | |
656 | /* | |
657 | * We need to consume the current entry to see | |
658 | * the next one. | |
659 | */ | |
12883efb | 660 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, |
66a8cb95 | 661 | NULL, NULL); |
12883efb | 662 | event = ring_buffer_peek(iter->trace_buffer->buffer, iter->cpu, |
66a8cb95 | 663 | NULL, NULL); |
be1eca39 | 664 | } |
83a8df61 | 665 | |
be1eca39 JO |
666 | if (!event) |
667 | return NULL; | |
668 | ||
669 | next = ring_buffer_event_data(event); | |
83a8df61 | 670 | |
be1eca39 JO |
671 | if (data) { |
672 | /* | |
673 | * Save current and next entries for later reference | |
674 | * if the output fails. | |
675 | */ | |
676 | data->ent = *curr; | |
575570f0 SL |
677 | /* |
678 | * If the next event is not a return type, then | |
679 | * we only care about what type it is. Otherwise we can | |
680 | * safely copy the entire event. | |
681 | */ | |
682 | if (next->ent.type == TRACE_GRAPH_RET) | |
683 | data->ret = *next; | |
684 | else | |
685 | data->ret.ent.type = next->ent.type; | |
be1eca39 JO |
686 | } |
687 | } | |
83a8df61 FW |
688 | |
689 | if (next->ent.type != TRACE_GRAPH_RET) | |
b91facc3 | 690 | return NULL; |
83a8df61 FW |
691 | |
692 | if (curr->ent.pid != next->ent.pid || | |
693 | curr->graph_ent.func != next->ret.func) | |
b91facc3 | 694 | return NULL; |
83a8df61 | 695 | |
b91facc3 FW |
696 | /* this is a leaf, now advance the iterator */ |
697 | if (ring_iter) | |
698 | ring_buffer_read(ring_iter, NULL); | |
699 | ||
700 | return next; | |
83a8df61 FW |
701 | } |
702 | ||
9d9add34 | 703 | static void print_graph_abs_time(u64 t, struct trace_seq *s) |
d1f9cbd7 FW |
704 | { |
705 | unsigned long usecs_rem; | |
706 | ||
707 | usecs_rem = do_div(t, NSEC_PER_SEC); | |
708 | usecs_rem /= 1000; | |
709 | ||
9d9add34 SRRH |
710 | trace_seq_printf(s, "%5lu.%06lu | ", |
711 | (unsigned long)t, usecs_rem); | |
d1f9cbd7 FW |
712 | } |
713 | ||
9d9add34 | 714 | static void |
d1f9cbd7 | 715 | print_graph_irq(struct trace_iterator *iter, unsigned long addr, |
d7a8d9e9 | 716 | enum trace_type type, int cpu, pid_t pid, u32 flags) |
f8b755ac | 717 | { |
983f938a | 718 | struct trace_array *tr = iter->tr; |
d1f9cbd7 | 719 | struct trace_seq *s = &iter->seq; |
678f845e | 720 | struct trace_entry *ent = iter->ent; |
f8b755ac FW |
721 | |
722 | if (addr < (unsigned long)__irqentry_text_start || | |
723 | addr >= (unsigned long)__irqentry_text_end) | |
9d9add34 | 724 | return; |
f8b755ac | 725 | |
983f938a | 726 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
749230b0 | 727 | /* Absolute time */ |
9d9add34 SRRH |
728 | if (flags & TRACE_GRAPH_PRINT_ABS_TIME) |
729 | print_graph_abs_time(iter->ts, s); | |
d1f9cbd7 | 730 | |
749230b0 | 731 | /* Cpu */ |
9d9add34 SRRH |
732 | if (flags & TRACE_GRAPH_PRINT_CPU) |
733 | print_graph_cpu(s, cpu); | |
49ff5903 | 734 | |
749230b0 JO |
735 | /* Proc */ |
736 | if (flags & TRACE_GRAPH_PRINT_PROC) { | |
9d9add34 SRRH |
737 | print_graph_proc(s, pid); |
738 | trace_seq_puts(s, " | "); | |
749230b0 | 739 | } |
678f845e DBO |
740 | |
741 | /* Latency format */ | |
983f938a | 742 | if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) |
9d9add34 | 743 | print_graph_lat_fmt(s, ent); |
9005f3eb | 744 | } |
f8b755ac | 745 | |
9005f3eb | 746 | /* No overhead */ |
983f938a | 747 | print_graph_duration(tr, 0, s, flags | FLAGS_FILL_START); |
f8b755ac | 748 | |
9005f3eb | 749 | if (type == TRACE_GRAPH_ENT) |
9d9add34 | 750 | trace_seq_puts(s, "==========>"); |
9005f3eb | 751 | else |
9d9add34 | 752 | trace_seq_puts(s, "<=========="); |
9005f3eb | 753 | |
983f938a | 754 | print_graph_duration(tr, 0, s, flags | FLAGS_FILL_END); |
9d9add34 | 755 | trace_seq_putc(s, '\n'); |
f8b755ac | 756 | } |
83a8df61 | 757 | |
9d9add34 | 758 | void |
0706f1c4 | 759 | trace_print_graph_duration(unsigned long long duration, struct trace_seq *s) |
83a8df61 FW |
760 | { |
761 | unsigned long nsecs_rem = do_div(duration, 1000); | |
166d3c79 | 762 | /* log10(ULONG_MAX) + '\0' */ |
4526d067 | 763 | char usecs_str[21]; |
166d3c79 | 764 | char nsecs_str[5]; |
9d9add34 | 765 | int len; |
166d3c79 FW |
766 | int i; |
767 | ||
4526d067 | 768 | sprintf(usecs_str, "%lu", (unsigned long) duration); |
166d3c79 FW |
769 | |
770 | /* Print msecs */ | |
9d9add34 | 771 | trace_seq_printf(s, "%s", usecs_str); |
166d3c79 | 772 | |
4526d067 | 773 | len = strlen(usecs_str); |
166d3c79 FW |
774 | |
775 | /* Print nsecs (we don't want to exceed 7 numbers) */ | |
776 | if (len < 7) { | |
14cae9bd BP |
777 | size_t slen = min_t(size_t, sizeof(nsecs_str), 8UL - len); |
778 | ||
779 | snprintf(nsecs_str, slen, "%03lu", nsecs_rem); | |
9d9add34 | 780 | trace_seq_printf(s, ".%s", nsecs_str); |
82c355e8 | 781 | len += strlen(nsecs_str) + 1; |
166d3c79 FW |
782 | } |
783 | ||
9d9add34 | 784 | trace_seq_puts(s, " us "); |
166d3c79 FW |
785 | |
786 | /* Print remaining spaces to fit the row's width */ | |
82c355e8 | 787 | for (i = len; i < 8; i++) |
9d9add34 | 788 | trace_seq_putc(s, ' '); |
0706f1c4 SR |
789 | } |
790 | ||
9d9add34 | 791 | static void |
983f938a SRRH |
792 | print_graph_duration(struct trace_array *tr, unsigned long long duration, |
793 | struct trace_seq *s, u32 flags) | |
0706f1c4 | 794 | { |
749230b0 | 795 | if (!(flags & TRACE_GRAPH_PRINT_DURATION) || |
983f938a | 796 | !(tr->trace_flags & TRACE_ITER_CONTEXT_INFO)) |
9d9add34 | 797 | return; |
ffeb80fc JO |
798 | |
799 | /* No real adata, just filling the column with spaces */ | |
6fc84ea7 SRRH |
800 | switch (flags & TRACE_GRAPH_PRINT_FILL_MASK) { |
801 | case FLAGS_FILL_FULL: | |
9d9add34 SRRH |
802 | trace_seq_puts(s, " | "); |
803 | return; | |
6fc84ea7 | 804 | case FLAGS_FILL_START: |
9d9add34 SRRH |
805 | trace_seq_puts(s, " "); |
806 | return; | |
6fc84ea7 | 807 | case FLAGS_FILL_END: |
9d9add34 SRRH |
808 | trace_seq_puts(s, " |"); |
809 | return; | |
ffeb80fc JO |
810 | } |
811 | ||
812 | /* Signal a overhead of time execution to the output */ | |
8e1e1df2 BP |
813 | if (flags & TRACE_GRAPH_PRINT_OVERHEAD) |
814 | trace_seq_printf(s, "%c ", trace_find_mark(duration)); | |
815 | else | |
9d9add34 | 816 | trace_seq_puts(s, " "); |
0706f1c4 | 817 | |
9d9add34 SRRH |
818 | trace_print_graph_duration(duration, s); |
819 | trace_seq_puts(s, "| "); | |
83a8df61 FW |
820 | } |
821 | ||
83a8df61 | 822 | /* Case of a leaf function on its call entry */ |
287b6e68 | 823 | static enum print_line_t |
83a8df61 | 824 | print_graph_entry_leaf(struct trace_iterator *iter, |
b91facc3 | 825 | struct ftrace_graph_ent_entry *entry, |
d7a8d9e9 JO |
826 | struct ftrace_graph_ret_entry *ret_entry, |
827 | struct trace_seq *s, u32 flags) | |
fb52607a | 828 | { |
2fbcdb35 | 829 | struct fgraph_data *data = iter->private; |
983f938a | 830 | struct trace_array *tr = iter->tr; |
83a8df61 | 831 | struct ftrace_graph_ret *graph_ret; |
83a8df61 FW |
832 | struct ftrace_graph_ent *call; |
833 | unsigned long long duration; | |
1a056155 | 834 | int i; |
fb52607a | 835 | |
83a8df61 FW |
836 | graph_ret = &ret_entry->ret; |
837 | call = &entry->graph_ent; | |
838 | duration = graph_ret->rettime - graph_ret->calltime; | |
839 | ||
2fbcdb35 | 840 | if (data) { |
f1c7f517 | 841 | struct fgraph_cpu_data *cpu_data; |
2fbcdb35 | 842 | int cpu = iter->cpu; |
f1c7f517 SR |
843 | |
844 | cpu_data = per_cpu_ptr(data->cpu_data, cpu); | |
2fbcdb35 SR |
845 | |
846 | /* | |
847 | * Comments display at + 1 to depth. Since | |
848 | * this is a leaf function, keep the comments | |
849 | * equal to this depth. | |
850 | */ | |
f1c7f517 SR |
851 | cpu_data->depth = call->depth - 1; |
852 | ||
853 | /* No need to keep this function around for this depth */ | |
854 | if (call->depth < FTRACE_RETFUNC_DEPTH) | |
855 | cpu_data->enter_funcs[call->depth] = 0; | |
2fbcdb35 SR |
856 | } |
857 | ||
ffeb80fc | 858 | /* Overhead and duration */ |
983f938a | 859 | print_graph_duration(tr, duration, s, flags); |
1a056155 | 860 | |
83a8df61 | 861 | /* Function */ |
9d9add34 SRRH |
862 | for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) |
863 | trace_seq_putc(s, ' '); | |
83a8df61 | 864 | |
9d9add34 | 865 | trace_seq_printf(s, "%ps();\n", (void *)call->func); |
83a8df61 | 866 | |
9d9add34 | 867 | return trace_handle_return(s); |
83a8df61 FW |
868 | } |
869 | ||
870 | static enum print_line_t | |
2fbcdb35 SR |
871 | print_graph_entry_nested(struct trace_iterator *iter, |
872 | struct ftrace_graph_ent_entry *entry, | |
d7a8d9e9 | 873 | struct trace_seq *s, int cpu, u32 flags) |
83a8df61 | 874 | { |
83a8df61 | 875 | struct ftrace_graph_ent *call = &entry->graph_ent; |
2fbcdb35 | 876 | struct fgraph_data *data = iter->private; |
983f938a | 877 | struct trace_array *tr = iter->tr; |
2fbcdb35 SR |
878 | int i; |
879 | ||
880 | if (data) { | |
f1c7f517 | 881 | struct fgraph_cpu_data *cpu_data; |
2fbcdb35 | 882 | int cpu = iter->cpu; |
2fbcdb35 | 883 | |
f1c7f517 SR |
884 | cpu_data = per_cpu_ptr(data->cpu_data, cpu); |
885 | cpu_data->depth = call->depth; | |
886 | ||
887 | /* Save this function pointer to see if the exit matches */ | |
888 | if (call->depth < FTRACE_RETFUNC_DEPTH) | |
889 | cpu_data->enter_funcs[call->depth] = call->func; | |
2fbcdb35 | 890 | } |
83a8df61 | 891 | |
9005f3eb | 892 | /* No time */ |
983f938a | 893 | print_graph_duration(tr, 0, s, flags | FLAGS_FILL_FULL); |
f8b755ac | 894 | |
83a8df61 | 895 | /* Function */ |
9d9add34 SRRH |
896 | for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) |
897 | trace_seq_putc(s, ' '); | |
898 | ||
899 | trace_seq_printf(s, "%ps() {\n", (void *)call->func); | |
287b6e68 | 900 | |
9d9add34 | 901 | if (trace_seq_has_overflowed(s)) |
83a8df61 FW |
902 | return TRACE_TYPE_PARTIAL_LINE; |
903 | ||
b91facc3 FW |
904 | /* |
905 | * we already consumed the current entry to check the next one | |
906 | * and see if this is a leaf. | |
907 | */ | |
908 | return TRACE_TYPE_NO_CONSUME; | |
287b6e68 FW |
909 | } |
910 | ||
9d9add34 | 911 | static void |
ac5f6c96 | 912 | print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s, |
d7a8d9e9 | 913 | int type, unsigned long addr, u32 flags) |
83a8df61 | 914 | { |
2fbcdb35 | 915 | struct fgraph_data *data = iter->private; |
83a8df61 | 916 | struct trace_entry *ent = iter->ent; |
983f938a | 917 | struct trace_array *tr = iter->tr; |
ac5f6c96 | 918 | int cpu = iter->cpu; |
83a8df61 | 919 | |
1a056155 | 920 | /* Pid */ |
9d9add34 | 921 | verif_pid(s, ent->pid, cpu, data); |
9005f3eb | 922 | |
9d9add34 | 923 | if (type) |
ac5f6c96 | 924 | /* Interrupt */ |
9d9add34 | 925 | print_graph_irq(iter, addr, type, cpu, ent->pid, flags); |
83a8df61 | 926 | |
983f938a | 927 | if (!(tr->trace_flags & TRACE_ITER_CONTEXT_INFO)) |
9d9add34 | 928 | return; |
749230b0 | 929 | |
9005f3eb | 930 | /* Absolute time */ |
9d9add34 SRRH |
931 | if (flags & TRACE_GRAPH_PRINT_ABS_TIME) |
932 | print_graph_abs_time(iter->ts, s); | |
9005f3eb | 933 | |
1a056155 | 934 | /* Cpu */ |
9d9add34 SRRH |
935 | if (flags & TRACE_GRAPH_PRINT_CPU) |
936 | print_graph_cpu(s, cpu); | |
11e84acc FW |
937 | |
938 | /* Proc */ | |
d7a8d9e9 | 939 | if (flags & TRACE_GRAPH_PRINT_PROC) { |
9d9add34 SRRH |
940 | print_graph_proc(s, ent->pid); |
941 | trace_seq_puts(s, " | "); | |
1a056155 | 942 | } |
83a8df61 | 943 | |
49ff5903 | 944 | /* Latency format */ |
983f938a | 945 | if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) |
9d9add34 | 946 | print_graph_lat_fmt(s, ent); |
49ff5903 | 947 | |
9d9add34 | 948 | return; |
ac5f6c96 SR |
949 | } |
950 | ||
2bd16212 JO |
951 | /* |
952 | * Entry check for irq code | |
953 | * | |
954 | * returns 1 if | |
955 | * - we are inside irq code | |
25985edc | 956 | * - we just entered irq code |
2bd16212 JO |
957 | * |
958 | * retunns 0 if | |
959 | * - funcgraph-interrupts option is set | |
960 | * - we are not inside irq code | |
961 | */ | |
962 | static int | |
963 | check_irq_entry(struct trace_iterator *iter, u32 flags, | |
964 | unsigned long addr, int depth) | |
965 | { | |
966 | int cpu = iter->cpu; | |
a9d61173 | 967 | int *depth_irq; |
2bd16212 | 968 | struct fgraph_data *data = iter->private; |
2bd16212 | 969 | |
a9d61173 JO |
970 | /* |
971 | * If we are either displaying irqs, or we got called as | |
972 | * a graph event and private data does not exist, | |
973 | * then we bypass the irq check. | |
974 | */ | |
975 | if ((flags & TRACE_GRAPH_PRINT_IRQS) || | |
976 | (!data)) | |
2bd16212 JO |
977 | return 0; |
978 | ||
a9d61173 JO |
979 | depth_irq = &(per_cpu_ptr(data->cpu_data, cpu)->depth_irq); |
980 | ||
2bd16212 JO |
981 | /* |
982 | * We are inside the irq code | |
983 | */ | |
984 | if (*depth_irq >= 0) | |
985 | return 1; | |
986 | ||
987 | if ((addr < (unsigned long)__irqentry_text_start) || | |
988 | (addr >= (unsigned long)__irqentry_text_end)) | |
989 | return 0; | |
990 | ||
991 | /* | |
992 | * We are entering irq code. | |
993 | */ | |
994 | *depth_irq = depth; | |
995 | return 1; | |
996 | } | |
997 | ||
998 | /* | |
999 | * Return check for irq code | |
1000 | * | |
1001 | * returns 1 if | |
1002 | * - we are inside irq code | |
1003 | * - we just left irq code | |
1004 | * | |
1005 | * returns 0 if | |
1006 | * - funcgraph-interrupts option is set | |
1007 | * - we are not inside irq code | |
1008 | */ | |
1009 | static int | |
1010 | check_irq_return(struct trace_iterator *iter, u32 flags, int depth) | |
1011 | { | |
1012 | int cpu = iter->cpu; | |
a9d61173 | 1013 | int *depth_irq; |
2bd16212 | 1014 | struct fgraph_data *data = iter->private; |
2bd16212 | 1015 | |
a9d61173 JO |
1016 | /* |
1017 | * If we are either displaying irqs, or we got called as | |
1018 | * a graph event and private data does not exist, | |
1019 | * then we bypass the irq check. | |
1020 | */ | |
1021 | if ((flags & TRACE_GRAPH_PRINT_IRQS) || | |
1022 | (!data)) | |
2bd16212 JO |
1023 | return 0; |
1024 | ||
a9d61173 JO |
1025 | depth_irq = &(per_cpu_ptr(data->cpu_data, cpu)->depth_irq); |
1026 | ||
2bd16212 JO |
1027 | /* |
1028 | * We are not inside the irq code. | |
1029 | */ | |
1030 | if (*depth_irq == -1) | |
1031 | return 0; | |
1032 | ||
1033 | /* | |
1034 | * We are inside the irq code, and this is returning entry. | |
1035 | * Let's not trace it and clear the entry depth, since | |
1036 | * we are out of irq code. | |
1037 | * | |
1038 | * This condition ensures that we 'leave the irq code' once | |
1039 | * we are out of the entry depth. Thus protecting us from | |
1040 | * the RETURN entry loss. | |
1041 | */ | |
1042 | if (*depth_irq >= depth) { | |
1043 | *depth_irq = -1; | |
1044 | return 1; | |
1045 | } | |
1046 | ||
1047 | /* | |
1048 | * We are inside the irq code, and this is not the entry. | |
1049 | */ | |
1050 | return 1; | |
1051 | } | |
1052 | ||
ac5f6c96 SR |
1053 | static enum print_line_t |
1054 | print_graph_entry(struct ftrace_graph_ent_entry *field, struct trace_seq *s, | |
d7a8d9e9 | 1055 | struct trace_iterator *iter, u32 flags) |
ac5f6c96 | 1056 | { |
be1eca39 | 1057 | struct fgraph_data *data = iter->private; |
ac5f6c96 SR |
1058 | struct ftrace_graph_ent *call = &field->graph_ent; |
1059 | struct ftrace_graph_ret_entry *leaf_ret; | |
be1eca39 JO |
1060 | static enum print_line_t ret; |
1061 | int cpu = iter->cpu; | |
ac5f6c96 | 1062 | |
2bd16212 JO |
1063 | if (check_irq_entry(iter, flags, call->func, call->depth)) |
1064 | return TRACE_TYPE_HANDLED; | |
1065 | ||
9d9add34 | 1066 | print_graph_prologue(iter, s, TRACE_GRAPH_ENT, call->func, flags); |
ac5f6c96 | 1067 | |
b91facc3 FW |
1068 | leaf_ret = get_return_for_leaf(iter, field); |
1069 | if (leaf_ret) | |
d7a8d9e9 | 1070 | ret = print_graph_entry_leaf(iter, field, leaf_ret, s, flags); |
83a8df61 | 1071 | else |
d7a8d9e9 | 1072 | ret = print_graph_entry_nested(iter, field, s, cpu, flags); |
83a8df61 | 1073 | |
be1eca39 JO |
1074 | if (data) { |
1075 | /* | |
1076 | * If we failed to write our output, then we need to make | |
1077 | * note of it. Because we already consumed our entry. | |
1078 | */ | |
1079 | if (s->full) { | |
1080 | data->failed = 1; | |
1081 | data->cpu = cpu; | |
1082 | } else | |
1083 | data->failed = 0; | |
1084 | } | |
1085 | ||
1086 | return ret; | |
83a8df61 FW |
1087 | } |
1088 | ||
287b6e68 FW |
1089 | static enum print_line_t |
1090 | print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s, | |
d7a8d9e9 JO |
1091 | struct trace_entry *ent, struct trace_iterator *iter, |
1092 | u32 flags) | |
287b6e68 | 1093 | { |
83a8df61 | 1094 | unsigned long long duration = trace->rettime - trace->calltime; |
2fbcdb35 | 1095 | struct fgraph_data *data = iter->private; |
983f938a | 1096 | struct trace_array *tr = iter->tr; |
2fbcdb35 SR |
1097 | pid_t pid = ent->pid; |
1098 | int cpu = iter->cpu; | |
f1c7f517 | 1099 | int func_match = 1; |
2fbcdb35 SR |
1100 | int i; |
1101 | ||
2bd16212 JO |
1102 | if (check_irq_return(iter, flags, trace->depth)) |
1103 | return TRACE_TYPE_HANDLED; | |
1104 | ||
2fbcdb35 | 1105 | if (data) { |
f1c7f517 SR |
1106 | struct fgraph_cpu_data *cpu_data; |
1107 | int cpu = iter->cpu; | |
1108 | ||
1109 | cpu_data = per_cpu_ptr(data->cpu_data, cpu); | |
2fbcdb35 SR |
1110 | |
1111 | /* | |
1112 | * Comments display at + 1 to depth. This is the | |
1113 | * return from a function, we now want the comments | |
1114 | * to display at the same level of the bracket. | |
1115 | */ | |
f1c7f517 SR |
1116 | cpu_data->depth = trace->depth - 1; |
1117 | ||
1118 | if (trace->depth < FTRACE_RETFUNC_DEPTH) { | |
1119 | if (cpu_data->enter_funcs[trace->depth] != trace->func) | |
1120 | func_match = 0; | |
1121 | cpu_data->enter_funcs[trace->depth] = 0; | |
1122 | } | |
2fbcdb35 | 1123 | } |
287b6e68 | 1124 | |
9d9add34 | 1125 | print_graph_prologue(iter, s, 0, 0, flags); |
437f24fb | 1126 | |
ffeb80fc | 1127 | /* Overhead and duration */ |
983f938a | 1128 | print_graph_duration(tr, duration, s, flags); |
1a056155 | 1129 | |
83a8df61 | 1130 | /* Closing brace */ |
9d9add34 SRRH |
1131 | for (i = 0; i < trace->depth * TRACE_GRAPH_INDENT; i++) |
1132 | trace_seq_putc(s, ' '); | |
287b6e68 | 1133 | |
f1c7f517 SR |
1134 | /* |
1135 | * If the return function does not have a matching entry, | |
1136 | * then the entry was lost. Instead of just printing | |
1137 | * the '}' and letting the user guess what function this | |
607e3a29 RE |
1138 | * belongs to, write out the function name. Always do |
1139 | * that if the funcgraph-tail option is enabled. | |
f1c7f517 | 1140 | */ |
9d9add34 SRRH |
1141 | if (func_match && !(flags & TRACE_GRAPH_PRINT_TAIL)) |
1142 | trace_seq_puts(s, "}\n"); | |
1143 | else | |
1144 | trace_seq_printf(s, "} /* %ps */\n", (void *)trace->func); | |
fb52607a | 1145 | |
83a8df61 | 1146 | /* Overrun */ |
9d9add34 SRRH |
1147 | if (flags & TRACE_GRAPH_PRINT_OVERRUN) |
1148 | trace_seq_printf(s, " (Overruns: %lu)\n", | |
1149 | trace->overrun); | |
f8b755ac | 1150 | |
9d9add34 SRRH |
1151 | print_graph_irq(iter, trace->func, TRACE_GRAPH_RET, |
1152 | cpu, pid, flags); | |
f8b755ac | 1153 | |
9d9add34 | 1154 | return trace_handle_return(s); |
287b6e68 FW |
1155 | } |
1156 | ||
1fd8f2a3 | 1157 | static enum print_line_t |
d7a8d9e9 JO |
1158 | print_graph_comment(struct trace_seq *s, struct trace_entry *ent, |
1159 | struct trace_iterator *iter, u32 flags) | |
1fd8f2a3 | 1160 | { |
983f938a SRRH |
1161 | struct trace_array *tr = iter->tr; |
1162 | unsigned long sym_flags = (tr->trace_flags & TRACE_ITER_SYM_MASK); | |
2fbcdb35 | 1163 | struct fgraph_data *data = iter->private; |
5087f8d2 | 1164 | struct trace_event *event; |
2fbcdb35 | 1165 | int depth = 0; |
1fd8f2a3 | 1166 | int ret; |
2fbcdb35 SR |
1167 | int i; |
1168 | ||
1169 | if (data) | |
be1eca39 | 1170 | depth = per_cpu_ptr(data->cpu_data, iter->cpu)->depth; |
9005f3eb | 1171 | |
9d9add34 | 1172 | print_graph_prologue(iter, s, 0, 0, flags); |
d1f9cbd7 | 1173 | |
9005f3eb | 1174 | /* No time */ |
983f938a | 1175 | print_graph_duration(tr, 0, s, flags | FLAGS_FILL_FULL); |
1fd8f2a3 | 1176 | |
1fd8f2a3 | 1177 | /* Indentation */ |
2fbcdb35 | 1178 | if (depth > 0) |
9d9add34 SRRH |
1179 | for (i = 0; i < (depth + 1) * TRACE_GRAPH_INDENT; i++) |
1180 | trace_seq_putc(s, ' '); | |
1fd8f2a3 FW |
1181 | |
1182 | /* The comment */ | |
9d9add34 | 1183 | trace_seq_puts(s, "/* "); |
769b0441 | 1184 | |
5087f8d2 SR |
1185 | switch (iter->ent->type) { |
1186 | case TRACE_BPRINT: | |
1187 | ret = trace_print_bprintk_msg_only(iter); | |
1188 | if (ret != TRACE_TYPE_HANDLED) | |
1189 | return ret; | |
1190 | break; | |
1191 | case TRACE_PRINT: | |
1192 | ret = trace_print_printk_msg_only(iter); | |
1193 | if (ret != TRACE_TYPE_HANDLED) | |
1194 | return ret; | |
1195 | break; | |
1196 | default: | |
1197 | event = ftrace_find_event(ent->type); | |
1198 | if (!event) | |
1199 | return TRACE_TYPE_UNHANDLED; | |
1200 | ||
a9a57763 | 1201 | ret = event->funcs->trace(iter, sym_flags, event); |
5087f8d2 SR |
1202 | if (ret != TRACE_TYPE_HANDLED) |
1203 | return ret; | |
1204 | } | |
1fd8f2a3 | 1205 | |
5ac48378 SRRH |
1206 | if (trace_seq_has_overflowed(s)) |
1207 | goto out; | |
1208 | ||
412d0bb5 | 1209 | /* Strip ending newline */ |
3a161d99 SRRH |
1210 | if (s->buffer[s->seq.len - 1] == '\n') { |
1211 | s->buffer[s->seq.len - 1] = '\0'; | |
1212 | s->seq.len--; | |
412d0bb5 FW |
1213 | } |
1214 | ||
9d9add34 | 1215 | trace_seq_puts(s, " */\n"); |
5ac48378 | 1216 | out: |
9d9add34 | 1217 | return trace_handle_return(s); |
1fd8f2a3 FW |
1218 | } |
1219 | ||
1220 | ||
287b6e68 | 1221 | enum print_line_t |
321e68b0 | 1222 | print_graph_function_flags(struct trace_iterator *iter, u32 flags) |
287b6e68 | 1223 | { |
be1eca39 JO |
1224 | struct ftrace_graph_ent_entry *field; |
1225 | struct fgraph_data *data = iter->private; | |
287b6e68 | 1226 | struct trace_entry *entry = iter->ent; |
5087f8d2 | 1227 | struct trace_seq *s = &iter->seq; |
be1eca39 JO |
1228 | int cpu = iter->cpu; |
1229 | int ret; | |
1230 | ||
1231 | if (data && per_cpu_ptr(data->cpu_data, cpu)->ignore) { | |
1232 | per_cpu_ptr(data->cpu_data, cpu)->ignore = 0; | |
1233 | return TRACE_TYPE_HANDLED; | |
1234 | } | |
1235 | ||
1236 | /* | |
1237 | * If the last output failed, there's a possibility we need | |
1238 | * to print out the missing entry which would never go out. | |
1239 | */ | |
1240 | if (data && data->failed) { | |
1241 | field = &data->ent; | |
1242 | iter->cpu = data->cpu; | |
d7a8d9e9 | 1243 | ret = print_graph_entry(field, s, iter, flags); |
be1eca39 JO |
1244 | if (ret == TRACE_TYPE_HANDLED && iter->cpu != cpu) { |
1245 | per_cpu_ptr(data->cpu_data, iter->cpu)->ignore = 1; | |
1246 | ret = TRACE_TYPE_NO_CONSUME; | |
1247 | } | |
1248 | iter->cpu = cpu; | |
1249 | return ret; | |
1250 | } | |
fb52607a | 1251 | |
287b6e68 FW |
1252 | switch (entry->type) { |
1253 | case TRACE_GRAPH_ENT: { | |
38ceb592 LJ |
1254 | /* |
1255 | * print_graph_entry() may consume the current event, | |
1256 | * thus @field may become invalid, so we need to save it. | |
1257 | * sizeof(struct ftrace_graph_ent_entry) is very small, | |
1258 | * it can be safely saved at the stack. | |
1259 | */ | |
be1eca39 | 1260 | struct ftrace_graph_ent_entry saved; |
287b6e68 | 1261 | trace_assign_type(field, entry); |
38ceb592 | 1262 | saved = *field; |
d7a8d9e9 | 1263 | return print_graph_entry(&saved, s, iter, flags); |
287b6e68 FW |
1264 | } |
1265 | case TRACE_GRAPH_RET: { | |
1266 | struct ftrace_graph_ret_entry *field; | |
1267 | trace_assign_type(field, entry); | |
d7a8d9e9 | 1268 | return print_graph_return(&field->ret, s, entry, iter, flags); |
287b6e68 | 1269 | } |
62b915f1 JO |
1270 | case TRACE_STACK: |
1271 | case TRACE_FN: | |
1272 | /* dont trace stack and functions as comments */ | |
1273 | return TRACE_TYPE_UNHANDLED; | |
1274 | ||
287b6e68 | 1275 | default: |
d7a8d9e9 | 1276 | return print_graph_comment(s, entry, iter, flags); |
fb52607a | 1277 | } |
5087f8d2 SR |
1278 | |
1279 | return TRACE_TYPE_HANDLED; | |
fb52607a FW |
1280 | } |
1281 | ||
d7a8d9e9 JO |
1282 | static enum print_line_t |
1283 | print_graph_function(struct trace_iterator *iter) | |
1284 | { | |
321e68b0 | 1285 | return print_graph_function_flags(iter, tracer_flags.val); |
d7a8d9e9 JO |
1286 | } |
1287 | ||
9106b693 | 1288 | static enum print_line_t |
a9a57763 SR |
1289 | print_graph_function_event(struct trace_iterator *iter, int flags, |
1290 | struct trace_event *event) | |
9106b693 JO |
1291 | { |
1292 | return print_graph_function(iter); | |
1293 | } | |
1294 | ||
d7a8d9e9 | 1295 | static void print_lat_header(struct seq_file *s, u32 flags) |
49ff5903 SR |
1296 | { |
1297 | static const char spaces[] = " " /* 16 spaces */ | |
1298 | " " /* 4 spaces */ | |
1299 | " "; /* 17 spaces */ | |
1300 | int size = 0; | |
1301 | ||
d7a8d9e9 | 1302 | if (flags & TRACE_GRAPH_PRINT_ABS_TIME) |
49ff5903 | 1303 | size += 16; |
d7a8d9e9 | 1304 | if (flags & TRACE_GRAPH_PRINT_CPU) |
49ff5903 | 1305 | size += 4; |
d7a8d9e9 | 1306 | if (flags & TRACE_GRAPH_PRINT_PROC) |
49ff5903 SR |
1307 | size += 17; |
1308 | ||
1309 | seq_printf(s, "#%.*s _-----=> irqs-off \n", size, spaces); | |
1310 | seq_printf(s, "#%.*s / _----=> need-resched \n", size, spaces); | |
1311 | seq_printf(s, "#%.*s| / _---=> hardirq/softirq \n", size, spaces); | |
1312 | seq_printf(s, "#%.*s|| / _--=> preempt-depth \n", size, spaces); | |
199abfab | 1313 | seq_printf(s, "#%.*s||| / \n", size, spaces); |
49ff5903 SR |
1314 | } |
1315 | ||
983f938a SRRH |
1316 | static void __print_graph_headers_flags(struct trace_array *tr, |
1317 | struct seq_file *s, u32 flags) | |
decbec38 | 1318 | { |
983f938a | 1319 | int lat = tr->trace_flags & TRACE_ITER_LATENCY_FMT; |
49ff5903 SR |
1320 | |
1321 | if (lat) | |
d7a8d9e9 | 1322 | print_lat_header(s, flags); |
49ff5903 | 1323 | |
decbec38 | 1324 | /* 1st line */ |
1177e436 | 1325 | seq_putc(s, '#'); |
d7a8d9e9 | 1326 | if (flags & TRACE_GRAPH_PRINT_ABS_TIME) |
fa6f0cc7 | 1327 | seq_puts(s, " TIME "); |
d7a8d9e9 | 1328 | if (flags & TRACE_GRAPH_PRINT_CPU) |
fa6f0cc7 | 1329 | seq_puts(s, " CPU"); |
d7a8d9e9 | 1330 | if (flags & TRACE_GRAPH_PRINT_PROC) |
fa6f0cc7 | 1331 | seq_puts(s, " TASK/PID "); |
49ff5903 | 1332 | if (lat) |
fa6f0cc7 | 1333 | seq_puts(s, "||||"); |
d7a8d9e9 | 1334 | if (flags & TRACE_GRAPH_PRINT_DURATION) |
fa6f0cc7 RV |
1335 | seq_puts(s, " DURATION "); |
1336 | seq_puts(s, " FUNCTION CALLS\n"); | |
decbec38 FW |
1337 | |
1338 | /* 2nd line */ | |
1177e436 | 1339 | seq_putc(s, '#'); |
d7a8d9e9 | 1340 | if (flags & TRACE_GRAPH_PRINT_ABS_TIME) |
fa6f0cc7 | 1341 | seq_puts(s, " | "); |
d7a8d9e9 | 1342 | if (flags & TRACE_GRAPH_PRINT_CPU) |
fa6f0cc7 | 1343 | seq_puts(s, " | "); |
d7a8d9e9 | 1344 | if (flags & TRACE_GRAPH_PRINT_PROC) |
fa6f0cc7 | 1345 | seq_puts(s, " | | "); |
49ff5903 | 1346 | if (lat) |
fa6f0cc7 | 1347 | seq_puts(s, "||||"); |
d7a8d9e9 | 1348 | if (flags & TRACE_GRAPH_PRINT_DURATION) |
fa6f0cc7 RV |
1349 | seq_puts(s, " | | "); |
1350 | seq_puts(s, " | | | |\n"); | |
decbec38 | 1351 | } |
9005f3eb | 1352 | |
ba1afef6 | 1353 | static void print_graph_headers(struct seq_file *s) |
d7a8d9e9 JO |
1354 | { |
1355 | print_graph_headers_flags(s, tracer_flags.val); | |
1356 | } | |
1357 | ||
0a772620 JO |
1358 | void print_graph_headers_flags(struct seq_file *s, u32 flags) |
1359 | { | |
1360 | struct trace_iterator *iter = s->private; | |
983f938a | 1361 | struct trace_array *tr = iter->tr; |
0a772620 | 1362 | |
983f938a | 1363 | if (!(tr->trace_flags & TRACE_ITER_CONTEXT_INFO)) |
749230b0 JO |
1364 | return; |
1365 | ||
983f938a | 1366 | if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) { |
0a772620 JO |
1367 | /* print nothing if the buffers are empty */ |
1368 | if (trace_empty(iter)) | |
1369 | return; | |
1370 | ||
1371 | print_trace_header(s, iter); | |
321e68b0 | 1372 | } |
0a772620 | 1373 | |
983f938a | 1374 | __print_graph_headers_flags(tr, s, flags); |
0a772620 JO |
1375 | } |
1376 | ||
62b915f1 | 1377 | void graph_trace_open(struct trace_iterator *iter) |
9005f3eb | 1378 | { |
2fbcdb35 | 1379 | /* pid and depth on the last trace processed */ |
be1eca39 | 1380 | struct fgraph_data *data; |
ef99b88b | 1381 | gfp_t gfpflags; |
9005f3eb FW |
1382 | int cpu; |
1383 | ||
be1eca39 JO |
1384 | iter->private = NULL; |
1385 | ||
ef99b88b RV |
1386 | /* We can be called in atomic context via ftrace_dump() */ |
1387 | gfpflags = (in_atomic() || irqs_disabled()) ? GFP_ATOMIC : GFP_KERNEL; | |
1388 | ||
1389 | data = kzalloc(sizeof(*data), gfpflags); | |
2fbcdb35 | 1390 | if (!data) |
be1eca39 JO |
1391 | goto out_err; |
1392 | ||
ef99b88b | 1393 | data->cpu_data = alloc_percpu_gfp(struct fgraph_cpu_data, gfpflags); |
be1eca39 JO |
1394 | if (!data->cpu_data) |
1395 | goto out_err_free; | |
1396 | ||
1397 | for_each_possible_cpu(cpu) { | |
1398 | pid_t *pid = &(per_cpu_ptr(data->cpu_data, cpu)->last_pid); | |
1399 | int *depth = &(per_cpu_ptr(data->cpu_data, cpu)->depth); | |
1400 | int *ignore = &(per_cpu_ptr(data->cpu_data, cpu)->ignore); | |
2bd16212 JO |
1401 | int *depth_irq = &(per_cpu_ptr(data->cpu_data, cpu)->depth_irq); |
1402 | ||
be1eca39 JO |
1403 | *pid = -1; |
1404 | *depth = 0; | |
1405 | *ignore = 0; | |
2bd16212 | 1406 | *depth_irq = -1; |
be1eca39 | 1407 | } |
9005f3eb | 1408 | |
2fbcdb35 | 1409 | iter->private = data; |
be1eca39 JO |
1410 | |
1411 | return; | |
1412 | ||
1413 | out_err_free: | |
1414 | kfree(data); | |
1415 | out_err: | |
a395d6a7 | 1416 | pr_warn("function graph tracer: not enough memory\n"); |
9005f3eb FW |
1417 | } |
1418 | ||
62b915f1 | 1419 | void graph_trace_close(struct trace_iterator *iter) |
9005f3eb | 1420 | { |
be1eca39 JO |
1421 | struct fgraph_data *data = iter->private; |
1422 | ||
1423 | if (data) { | |
1424 | free_percpu(data->cpu_data); | |
1425 | kfree(data); | |
1426 | } | |
9005f3eb FW |
1427 | } |
1428 | ||
8c1a49ae SRRH |
1429 | static int |
1430 | func_graph_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) | |
b304d044 SR |
1431 | { |
1432 | if (bit == TRACE_GRAPH_PRINT_IRQS) | |
1433 | ftrace_graph_skip_irqs = !set; | |
1434 | ||
55577204 SRRH |
1435 | if (bit == TRACE_GRAPH_SLEEP_TIME) |
1436 | ftrace_graph_sleep_time_control(set); | |
1437 | ||
1438 | if (bit == TRACE_GRAPH_GRAPH_TIME) | |
1439 | ftrace_graph_graph_time_control(set); | |
1440 | ||
b304d044 SR |
1441 | return 0; |
1442 | } | |
1443 | ||
a9a57763 SR |
1444 | static struct trace_event_functions graph_functions = { |
1445 | .trace = print_graph_function_event, | |
1446 | }; | |
1447 | ||
9106b693 JO |
1448 | static struct trace_event graph_trace_entry_event = { |
1449 | .type = TRACE_GRAPH_ENT, | |
a9a57763 | 1450 | .funcs = &graph_functions, |
9106b693 JO |
1451 | }; |
1452 | ||
1453 | static struct trace_event graph_trace_ret_event = { | |
1454 | .type = TRACE_GRAPH_RET, | |
a9a57763 | 1455 | .funcs = &graph_functions |
9106b693 JO |
1456 | }; |
1457 | ||
8f768993 | 1458 | static struct tracer graph_trace __tracer_data = { |
ef18012b | 1459 | .name = "function_graph", |
6508fa76 | 1460 | .update_thresh = graph_trace_update_thresh, |
9005f3eb | 1461 | .open = graph_trace_open, |
be1eca39 | 1462 | .pipe_open = graph_trace_open, |
9005f3eb | 1463 | .close = graph_trace_close, |
be1eca39 | 1464 | .pipe_close = graph_trace_close, |
ef18012b SR |
1465 | .init = graph_trace_init, |
1466 | .reset = graph_trace_reset, | |
decbec38 FW |
1467 | .print_line = print_graph_function, |
1468 | .print_header = print_graph_headers, | |
fb52607a | 1469 | .flags = &tracer_flags, |
b304d044 | 1470 | .set_flag = func_graph_set_flag, |
7447dce9 FW |
1471 | #ifdef CONFIG_FTRACE_SELFTEST |
1472 | .selftest = trace_selftest_startup_function_graph, | |
1473 | #endif | |
fb52607a FW |
1474 | }; |
1475 | ||
8741db53 SR |
1476 | |
1477 | static ssize_t | |
1478 | graph_depth_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
1479 | loff_t *ppos) | |
1480 | { | |
1481 | unsigned long val; | |
1482 | int ret; | |
1483 | ||
1484 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
1485 | if (ret) | |
1486 | return ret; | |
1487 | ||
1488 | max_depth = val; | |
1489 | ||
1490 | *ppos += cnt; | |
1491 | ||
1492 | return cnt; | |
1493 | } | |
1494 | ||
1495 | static ssize_t | |
1496 | graph_depth_read(struct file *filp, char __user *ubuf, size_t cnt, | |
1497 | loff_t *ppos) | |
1498 | { | |
1499 | char buf[15]; /* More than enough to hold UINT_MAX + "\n"*/ | |
1500 | int n; | |
1501 | ||
1502 | n = sprintf(buf, "%d\n", max_depth); | |
1503 | ||
1504 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, n); | |
1505 | } | |
1506 | ||
1507 | static const struct file_operations graph_depth_fops = { | |
1508 | .open = tracing_open_generic, | |
1509 | .write = graph_depth_write, | |
1510 | .read = graph_depth_read, | |
1511 | .llseek = generic_file_llseek, | |
1512 | }; | |
1513 | ||
8434dc93 | 1514 | static __init int init_graph_tracefs(void) |
8741db53 SR |
1515 | { |
1516 | struct dentry *d_tracer; | |
1517 | ||
1518 | d_tracer = tracing_init_dentry(); | |
14a5ae40 | 1519 | if (IS_ERR(d_tracer)) |
8741db53 SR |
1520 | return 0; |
1521 | ||
1522 | trace_create_file("max_graph_depth", 0644, d_tracer, | |
1523 | NULL, &graph_depth_fops); | |
1524 | ||
1525 | return 0; | |
1526 | } | |
8434dc93 | 1527 | fs_initcall(init_graph_tracefs); |
8741db53 | 1528 | |
fb52607a FW |
1529 | static __init int init_graph_trace(void) |
1530 | { | |
0c9e6f63 LJ |
1531 | max_bytes_for_cpu = snprintf(NULL, 0, "%d", nr_cpu_ids - 1); |
1532 | ||
9023c930 | 1533 | if (!register_trace_event(&graph_trace_entry_event)) { |
a395d6a7 | 1534 | pr_warn("Warning: could not register graph trace events\n"); |
9106b693 JO |
1535 | return 1; |
1536 | } | |
1537 | ||
9023c930 | 1538 | if (!register_trace_event(&graph_trace_ret_event)) { |
a395d6a7 | 1539 | pr_warn("Warning: could not register graph trace events\n"); |
9106b693 JO |
1540 | return 1; |
1541 | } | |
1542 | ||
fb52607a FW |
1543 | return register_tracer(&graph_trace); |
1544 | } | |
1545 | ||
6f415672 | 1546 | core_initcall(init_graph_trace); |