Commit | Line | Data |
---|---|---|
81d68a96 | 1 | /* |
73d8b8bc | 2 | * trace irqs off critical timings |
81d68a96 SR |
3 | * |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * From code in the latency_tracer, that is: | |
8 | * | |
9 | * Copyright (C) 2004-2006 Ingo Molnar | |
10 | * Copyright (C) 2004 William Lee Irwin III | |
11 | */ | |
12 | #include <linux/kallsyms.h> | |
13 | #include <linux/debugfs.h> | |
14 | #include <linux/uaccess.h> | |
15 | #include <linux/module.h> | |
16 | #include <linux/ftrace.h> | |
17 | #include <linux/fs.h> | |
18 | ||
19 | #include "trace.h" | |
20 | ||
21 | static struct trace_array *irqsoff_trace __read_mostly; | |
22 | static int tracer_enabled __read_mostly; | |
23 | ||
6cd8a4bb SR |
24 | static DEFINE_PER_CPU(int, tracing_cpu); |
25 | ||
89b2f978 SR |
26 | static DEFINE_SPINLOCK(max_trace_lock); |
27 | ||
6cd8a4bb SR |
28 | enum { |
29 | TRACER_IRQS_OFF = (1 << 1), | |
30 | TRACER_PREEMPT_OFF = (1 << 2), | |
31 | }; | |
32 | ||
33 | static int trace_type __read_mostly; | |
34 | ||
e9d25fe6 SR |
35 | static int save_lat_flag; |
36 | ||
62b915f1 JO |
37 | static void stop_irqsoff_tracer(struct trace_array *tr, int graph); |
38 | static int start_irqsoff_tracer(struct trace_array *tr, int graph); | |
39 | ||
6cd8a4bb | 40 | #ifdef CONFIG_PREEMPT_TRACER |
e309b41d | 41 | static inline int |
6cd8a4bb SR |
42 | preempt_trace(void) |
43 | { | |
44 | return ((trace_type & TRACER_PREEMPT_OFF) && preempt_count()); | |
45 | } | |
46 | #else | |
47 | # define preempt_trace() (0) | |
48 | #endif | |
49 | ||
50 | #ifdef CONFIG_IRQSOFF_TRACER | |
e309b41d | 51 | static inline int |
6cd8a4bb SR |
52 | irq_trace(void) |
53 | { | |
54 | return ((trace_type & TRACER_IRQS_OFF) && | |
55 | irqs_disabled()); | |
56 | } | |
57 | #else | |
58 | # define irq_trace() (0) | |
59 | #endif | |
60 | ||
62b915f1 JO |
61 | #define TRACE_DISPLAY_GRAPH 1 |
62 | ||
63 | static struct tracer_opt trace_opts[] = { | |
64 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
65 | /* display latency trace as call graph */ | |
66 | { TRACER_OPT(display-graph, TRACE_DISPLAY_GRAPH) }, | |
67 | #endif | |
68 | { } /* Empty entry */ | |
69 | }; | |
70 | ||
71 | static struct tracer_flags tracer_flags = { | |
72 | .val = 0, | |
73 | .opts = trace_opts, | |
74 | }; | |
75 | ||
76 | #define is_graph() (tracer_flags.val & TRACE_DISPLAY_GRAPH) | |
77 | ||
81d68a96 SR |
78 | /* |
79 | * Sequence count - we record it when starting a measurement and | |
80 | * skip the latency if the sequence has changed - some other section | |
81 | * did a maximum and could disturb our measurement with serial console | |
82 | * printouts, etc. Truly coinciding maximum latencies should be rare | |
25985edc | 83 | * and what happens together happens separately as well, so this doesn't |
81d68a96 SR |
84 | * decrease the validity of the maximum found: |
85 | */ | |
86 | static __cacheline_aligned_in_smp unsigned long max_sequence; | |
87 | ||
606576ce | 88 | #ifdef CONFIG_FUNCTION_TRACER |
81d68a96 | 89 | /* |
5e6d2b9c SR |
90 | * Prologue for the preempt and irqs off function tracers. |
91 | * | |
92 | * Returns 1 if it is OK to continue, and data->disabled is | |
93 | * incremented. | |
94 | * 0 if the trace is to be ignored, and data->disabled | |
95 | * is kept the same. | |
96 | * | |
97 | * Note, this function is also used outside this ifdef but | |
98 | * inside the #ifdef of the function graph tracer below. | |
99 | * This is OK, since the function graph tracer is | |
100 | * dependent on the function tracer. | |
81d68a96 | 101 | */ |
5e6d2b9c SR |
102 | static int func_prolog_dec(struct trace_array *tr, |
103 | struct trace_array_cpu **data, | |
104 | unsigned long *flags) | |
81d68a96 | 105 | { |
81d68a96 SR |
106 | long disabled; |
107 | int cpu; | |
108 | ||
361943ad SR |
109 | /* |
110 | * Does not matter if we preempt. We test the flags | |
111 | * afterward, to see if irqs are disabled or not. | |
112 | * If we preempt and get a false positive, the flags | |
113 | * test will fail. | |
114 | */ | |
115 | cpu = raw_smp_processor_id(); | |
116 | if (likely(!per_cpu(tracing_cpu, cpu))) | |
5e6d2b9c | 117 | return 0; |
81d68a96 | 118 | |
5e6d2b9c | 119 | local_save_flags(*flags); |
361943ad | 120 | /* slight chance to get a false positive on tracing_cpu */ |
5e6d2b9c SR |
121 | if (!irqs_disabled_flags(*flags)) |
122 | return 0; | |
81d68a96 | 123 | |
5e6d2b9c SR |
124 | *data = tr->data[cpu]; |
125 | disabled = atomic_inc_return(&(*data)->disabled); | |
81d68a96 SR |
126 | |
127 | if (likely(disabled == 1)) | |
5e6d2b9c SR |
128 | return 1; |
129 | ||
130 | atomic_dec(&(*data)->disabled); | |
131 | ||
132 | return 0; | |
133 | } | |
134 | ||
135 | /* | |
136 | * irqsoff uses its own tracer function to keep the overhead down: | |
137 | */ | |
138 | static void | |
139 | irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip) | |
140 | { | |
141 | struct trace_array *tr = irqsoff_trace; | |
142 | struct trace_array_cpu *data; | |
143 | unsigned long flags; | |
144 | ||
145 | if (!func_prolog_dec(tr, &data, &flags)) | |
146 | return; | |
147 | ||
148 | trace_function(tr, ip, parent_ip, flags, preempt_count()); | |
81d68a96 SR |
149 | |
150 | atomic_dec(&data->disabled); | |
151 | } | |
152 | ||
153 | static struct ftrace_ops trace_ops __read_mostly = | |
154 | { | |
155 | .func = irqsoff_tracer_call, | |
b848914c | 156 | .flags = FTRACE_OPS_FL_GLOBAL, |
81d68a96 | 157 | }; |
606576ce | 158 | #endif /* CONFIG_FUNCTION_TRACER */ |
81d68a96 | 159 | |
62b915f1 JO |
160 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
161 | static int irqsoff_set_flag(u32 old_flags, u32 bit, int set) | |
162 | { | |
163 | int cpu; | |
164 | ||
165 | if (!(bit & TRACE_DISPLAY_GRAPH)) | |
166 | return -EINVAL; | |
167 | ||
168 | if (!(is_graph() ^ set)) | |
169 | return 0; | |
170 | ||
171 | stop_irqsoff_tracer(irqsoff_trace, !set); | |
172 | ||
173 | for_each_possible_cpu(cpu) | |
174 | per_cpu(tracing_cpu, cpu) = 0; | |
175 | ||
176 | tracing_max_latency = 0; | |
177 | tracing_reset_online_cpus(irqsoff_trace); | |
178 | ||
179 | return start_irqsoff_tracer(irqsoff_trace, set); | |
180 | } | |
181 | ||
182 | static int irqsoff_graph_entry(struct ftrace_graph_ent *trace) | |
183 | { | |
184 | struct trace_array *tr = irqsoff_trace; | |
185 | struct trace_array_cpu *data; | |
186 | unsigned long flags; | |
62b915f1 | 187 | int ret; |
62b915f1 JO |
188 | int pc; |
189 | ||
5e6d2b9c | 190 | if (!func_prolog_dec(tr, &data, &flags)) |
62b915f1 JO |
191 | return 0; |
192 | ||
5e6d2b9c SR |
193 | pc = preempt_count(); |
194 | ret = __trace_graph_entry(tr, trace, flags, pc); | |
62b915f1 | 195 | atomic_dec(&data->disabled); |
5e6d2b9c | 196 | |
62b915f1 JO |
197 | return ret; |
198 | } | |
199 | ||
200 | static void irqsoff_graph_return(struct ftrace_graph_ret *trace) | |
201 | { | |
202 | struct trace_array *tr = irqsoff_trace; | |
203 | struct trace_array_cpu *data; | |
204 | unsigned long flags; | |
62b915f1 JO |
205 | int pc; |
206 | ||
5e6d2b9c | 207 | if (!func_prolog_dec(tr, &data, &flags)) |
62b915f1 JO |
208 | return; |
209 | ||
5e6d2b9c SR |
210 | pc = preempt_count(); |
211 | __trace_graph_return(tr, trace, flags, pc); | |
62b915f1 JO |
212 | atomic_dec(&data->disabled); |
213 | } | |
214 | ||
215 | static void irqsoff_trace_open(struct trace_iterator *iter) | |
216 | { | |
217 | if (is_graph()) | |
218 | graph_trace_open(iter); | |
219 | ||
220 | } | |
221 | ||
222 | static void irqsoff_trace_close(struct trace_iterator *iter) | |
223 | { | |
224 | if (iter->private) | |
225 | graph_trace_close(iter); | |
226 | } | |
227 | ||
228 | #define GRAPH_TRACER_FLAGS (TRACE_GRAPH_PRINT_CPU | \ | |
229 | TRACE_GRAPH_PRINT_PROC) | |
230 | ||
231 | static enum print_line_t irqsoff_print_line(struct trace_iterator *iter) | |
232 | { | |
62b915f1 JO |
233 | /* |
234 | * In graph mode call the graph tracer output function, | |
235 | * otherwise go with the TRACE_FN event handler | |
236 | */ | |
237 | if (is_graph()) | |
0a772620 | 238 | return print_graph_function_flags(iter, GRAPH_TRACER_FLAGS); |
62b915f1 JO |
239 | |
240 | return TRACE_TYPE_UNHANDLED; | |
241 | } | |
242 | ||
243 | static void irqsoff_print_header(struct seq_file *s) | |
244 | { | |
0a772620 JO |
245 | if (is_graph()) |
246 | print_graph_headers_flags(s, GRAPH_TRACER_FLAGS); | |
247 | else | |
62b915f1 JO |
248 | trace_default_header(s); |
249 | } | |
250 | ||
62b915f1 JO |
251 | static void |
252 | __trace_function(struct trace_array *tr, | |
253 | unsigned long ip, unsigned long parent_ip, | |
254 | unsigned long flags, int pc) | |
255 | { | |
0a772620 JO |
256 | if (is_graph()) |
257 | trace_graph_function(tr, ip, parent_ip, flags, pc); | |
258 | else | |
62b915f1 | 259 | trace_function(tr, ip, parent_ip, flags, pc); |
62b915f1 JO |
260 | } |
261 | ||
262 | #else | |
263 | #define __trace_function trace_function | |
264 | ||
265 | static int irqsoff_set_flag(u32 old_flags, u32 bit, int set) | |
266 | { | |
267 | return -EINVAL; | |
268 | } | |
269 | ||
270 | static int irqsoff_graph_entry(struct ftrace_graph_ent *trace) | |
271 | { | |
272 | return -1; | |
273 | } | |
274 | ||
275 | static enum print_line_t irqsoff_print_line(struct trace_iterator *iter) | |
276 | { | |
277 | return TRACE_TYPE_UNHANDLED; | |
278 | } | |
279 | ||
280 | static void irqsoff_graph_return(struct ftrace_graph_ret *trace) { } | |
281 | static void irqsoff_print_header(struct seq_file *s) { } | |
282 | static void irqsoff_trace_open(struct trace_iterator *iter) { } | |
283 | static void irqsoff_trace_close(struct trace_iterator *iter) { } | |
284 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
285 | ||
81d68a96 SR |
286 | /* |
287 | * Should this new latency be reported/recorded? | |
288 | */ | |
e309b41d | 289 | static int report_latency(cycle_t delta) |
81d68a96 SR |
290 | { |
291 | if (tracing_thresh) { | |
292 | if (delta < tracing_thresh) | |
293 | return 0; | |
294 | } else { | |
295 | if (delta <= tracing_max_latency) | |
296 | return 0; | |
297 | } | |
298 | return 1; | |
299 | } | |
300 | ||
e309b41d | 301 | static void |
81d68a96 SR |
302 | check_critical_timing(struct trace_array *tr, |
303 | struct trace_array_cpu *data, | |
304 | unsigned long parent_ip, | |
305 | int cpu) | |
306 | { | |
89b2f978 | 307 | cycle_t T0, T1, delta; |
81d68a96 | 308 | unsigned long flags; |
38697053 | 309 | int pc; |
81d68a96 | 310 | |
81d68a96 | 311 | T0 = data->preempt_timestamp; |
750ed1a4 | 312 | T1 = ftrace_now(cpu); |
81d68a96 SR |
313 | delta = T1-T0; |
314 | ||
315 | local_save_flags(flags); | |
316 | ||
6450c1d3 SR |
317 | pc = preempt_count(); |
318 | ||
81d68a96 SR |
319 | if (!report_latency(delta)) |
320 | goto out; | |
321 | ||
c7aafc54 | 322 | spin_lock_irqsave(&max_trace_lock, flags); |
81d68a96 | 323 | |
89b2f978 SR |
324 | /* check if we are still the max latency */ |
325 | if (!report_latency(delta)) | |
326 | goto out_unlock; | |
327 | ||
62b915f1 | 328 | __trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc); |
cc51a0fc SR |
329 | /* Skip 5 functions to get to the irq/preempt enable function */ |
330 | __trace_stack(tr, flags, 5, pc); | |
81d68a96 | 331 | |
81d68a96 | 332 | if (data->critical_sequence != max_sequence) |
89b2f978 | 333 | goto out_unlock; |
81d68a96 | 334 | |
81d68a96 SR |
335 | data->critical_end = parent_ip; |
336 | ||
b5130b1e CE |
337 | if (likely(!is_tracing_stopped())) { |
338 | tracing_max_latency = delta; | |
339 | update_max_tr_single(tr, current, cpu); | |
340 | } | |
81d68a96 | 341 | |
81d68a96 SR |
342 | max_sequence++; |
343 | ||
89b2f978 | 344 | out_unlock: |
c7aafc54 | 345 | spin_unlock_irqrestore(&max_trace_lock, flags); |
89b2f978 | 346 | |
81d68a96 SR |
347 | out: |
348 | data->critical_sequence = max_sequence; | |
750ed1a4 | 349 | data->preempt_timestamp = ftrace_now(cpu); |
62b915f1 | 350 | __trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc); |
81d68a96 SR |
351 | } |
352 | ||
e309b41d | 353 | static inline void |
81d68a96 SR |
354 | start_critical_timing(unsigned long ip, unsigned long parent_ip) |
355 | { | |
356 | int cpu; | |
357 | struct trace_array *tr = irqsoff_trace; | |
358 | struct trace_array_cpu *data; | |
359 | unsigned long flags; | |
360 | ||
361 | if (likely(!tracer_enabled)) | |
362 | return; | |
363 | ||
c5f888ca SR |
364 | cpu = raw_smp_processor_id(); |
365 | ||
366 | if (per_cpu(tracing_cpu, cpu)) | |
6cd8a4bb SR |
367 | return; |
368 | ||
81d68a96 SR |
369 | data = tr->data[cpu]; |
370 | ||
c5f888ca | 371 | if (unlikely(!data) || atomic_read(&data->disabled)) |
81d68a96 SR |
372 | return; |
373 | ||
374 | atomic_inc(&data->disabled); | |
375 | ||
376 | data->critical_sequence = max_sequence; | |
750ed1a4 | 377 | data->preempt_timestamp = ftrace_now(cpu); |
6cd8a4bb | 378 | data->critical_start = parent_ip ? : ip; |
81d68a96 SR |
379 | |
380 | local_save_flags(flags); | |
6cd8a4bb | 381 | |
62b915f1 | 382 | __trace_function(tr, ip, parent_ip, flags, preempt_count()); |
81d68a96 | 383 | |
c5f888ca | 384 | per_cpu(tracing_cpu, cpu) = 1; |
6cd8a4bb | 385 | |
81d68a96 SR |
386 | atomic_dec(&data->disabled); |
387 | } | |
388 | ||
e309b41d | 389 | static inline void |
81d68a96 SR |
390 | stop_critical_timing(unsigned long ip, unsigned long parent_ip) |
391 | { | |
392 | int cpu; | |
393 | struct trace_array *tr = irqsoff_trace; | |
394 | struct trace_array_cpu *data; | |
395 | unsigned long flags; | |
396 | ||
c5f888ca | 397 | cpu = raw_smp_processor_id(); |
6cd8a4bb | 398 | /* Always clear the tracing cpu on stopping the trace */ |
c5f888ca SR |
399 | if (unlikely(per_cpu(tracing_cpu, cpu))) |
400 | per_cpu(tracing_cpu, cpu) = 0; | |
6cd8a4bb SR |
401 | else |
402 | return; | |
403 | ||
404 | if (!tracer_enabled) | |
81d68a96 SR |
405 | return; |
406 | ||
81d68a96 SR |
407 | data = tr->data[cpu]; |
408 | ||
3928a8a2 | 409 | if (unlikely(!data) || |
81d68a96 SR |
410 | !data->critical_start || atomic_read(&data->disabled)) |
411 | return; | |
412 | ||
413 | atomic_inc(&data->disabled); | |
c5f888ca | 414 | |
81d68a96 | 415 | local_save_flags(flags); |
62b915f1 | 416 | __trace_function(tr, ip, parent_ip, flags, preempt_count()); |
6cd8a4bb | 417 | check_critical_timing(tr, data, parent_ip ? : ip, cpu); |
81d68a96 SR |
418 | data->critical_start = 0; |
419 | atomic_dec(&data->disabled); | |
420 | } | |
421 | ||
6cd8a4bb | 422 | /* start and stop critical timings used to for stoppage (in idle) */ |
e309b41d | 423 | void start_critical_timings(void) |
81d68a96 | 424 | { |
6cd8a4bb | 425 | if (preempt_trace() || irq_trace()) |
81d68a96 SR |
426 | start_critical_timing(CALLER_ADDR0, CALLER_ADDR1); |
427 | } | |
1fe37104 | 428 | EXPORT_SYMBOL_GPL(start_critical_timings); |
81d68a96 | 429 | |
e309b41d | 430 | void stop_critical_timings(void) |
81d68a96 | 431 | { |
6cd8a4bb | 432 | if (preempt_trace() || irq_trace()) |
81d68a96 SR |
433 | stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1); |
434 | } | |
1fe37104 | 435 | EXPORT_SYMBOL_GPL(stop_critical_timings); |
81d68a96 | 436 | |
6cd8a4bb | 437 | #ifdef CONFIG_IRQSOFF_TRACER |
81d68a96 | 438 | #ifdef CONFIG_PROVE_LOCKING |
e309b41d | 439 | void time_hardirqs_on(unsigned long a0, unsigned long a1) |
81d68a96 | 440 | { |
6cd8a4bb | 441 | if (!preempt_trace() && irq_trace()) |
81d68a96 SR |
442 | stop_critical_timing(a0, a1); |
443 | } | |
444 | ||
e309b41d | 445 | void time_hardirqs_off(unsigned long a0, unsigned long a1) |
81d68a96 | 446 | { |
6cd8a4bb | 447 | if (!preempt_trace() && irq_trace()) |
81d68a96 SR |
448 | start_critical_timing(a0, a1); |
449 | } | |
450 | ||
451 | #else /* !CONFIG_PROVE_LOCKING */ | |
452 | ||
453 | /* | |
454 | * Stubs: | |
455 | */ | |
456 | ||
81d68a96 SR |
457 | void trace_softirqs_on(unsigned long ip) |
458 | { | |
459 | } | |
460 | ||
461 | void trace_softirqs_off(unsigned long ip) | |
462 | { | |
463 | } | |
464 | ||
e309b41d | 465 | inline void print_irqtrace_events(struct task_struct *curr) |
81d68a96 SR |
466 | { |
467 | } | |
468 | ||
469 | /* | |
470 | * We are only interested in hardirq on/off events: | |
471 | */ | |
e309b41d | 472 | void trace_hardirqs_on(void) |
81d68a96 | 473 | { |
6cd8a4bb | 474 | if (!preempt_trace() && irq_trace()) |
81d68a96 SR |
475 | stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1); |
476 | } | |
477 | EXPORT_SYMBOL(trace_hardirqs_on); | |
478 | ||
e309b41d | 479 | void trace_hardirqs_off(void) |
81d68a96 | 480 | { |
6cd8a4bb | 481 | if (!preempt_trace() && irq_trace()) |
81d68a96 SR |
482 | start_critical_timing(CALLER_ADDR0, CALLER_ADDR1); |
483 | } | |
484 | EXPORT_SYMBOL(trace_hardirqs_off); | |
485 | ||
e309b41d | 486 | void trace_hardirqs_on_caller(unsigned long caller_addr) |
81d68a96 | 487 | { |
6cd8a4bb | 488 | if (!preempt_trace() && irq_trace()) |
81d68a96 SR |
489 | stop_critical_timing(CALLER_ADDR0, caller_addr); |
490 | } | |
491 | EXPORT_SYMBOL(trace_hardirqs_on_caller); | |
492 | ||
e309b41d | 493 | void trace_hardirqs_off_caller(unsigned long caller_addr) |
81d68a96 | 494 | { |
6cd8a4bb | 495 | if (!preempt_trace() && irq_trace()) |
81d68a96 SR |
496 | start_critical_timing(CALLER_ADDR0, caller_addr); |
497 | } | |
498 | EXPORT_SYMBOL(trace_hardirqs_off_caller); | |
499 | ||
500 | #endif /* CONFIG_PROVE_LOCKING */ | |
6cd8a4bb SR |
501 | #endif /* CONFIG_IRQSOFF_TRACER */ |
502 | ||
503 | #ifdef CONFIG_PREEMPT_TRACER | |
e309b41d | 504 | void trace_preempt_on(unsigned long a0, unsigned long a1) |
6cd8a4bb | 505 | { |
1e01cb0c SR |
506 | if (preempt_trace()) |
507 | stop_critical_timing(a0, a1); | |
6cd8a4bb SR |
508 | } |
509 | ||
e309b41d | 510 | void trace_preempt_off(unsigned long a0, unsigned long a1) |
6cd8a4bb | 511 | { |
1e01cb0c SR |
512 | if (preempt_trace()) |
513 | start_critical_timing(a0, a1); | |
6cd8a4bb SR |
514 | } |
515 | #endif /* CONFIG_PREEMPT_TRACER */ | |
81d68a96 | 516 | |
62b915f1 | 517 | static int start_irqsoff_tracer(struct trace_array *tr, int graph) |
81d68a96 | 518 | { |
62b915f1 JO |
519 | int ret = 0; |
520 | ||
521 | if (!graph) | |
522 | ret = register_ftrace_function(&trace_ops); | |
523 | else | |
524 | ret = register_ftrace_graph(&irqsoff_graph_return, | |
525 | &irqsoff_graph_entry); | |
526 | ||
527 | if (!ret && tracing_is_enabled()) | |
9036990d | 528 | tracer_enabled = 1; |
94523e81 | 529 | else |
9036990d | 530 | tracer_enabled = 0; |
62b915f1 JO |
531 | |
532 | return ret; | |
81d68a96 SR |
533 | } |
534 | ||
62b915f1 | 535 | static void stop_irqsoff_tracer(struct trace_array *tr, int graph) |
81d68a96 | 536 | { |
81d68a96 | 537 | tracer_enabled = 0; |
62b915f1 JO |
538 | |
539 | if (!graph) | |
540 | unregister_ftrace_function(&trace_ops); | |
541 | else | |
542 | unregister_ftrace_graph(); | |
81d68a96 SR |
543 | } |
544 | ||
6cd8a4bb | 545 | static void __irqsoff_tracer_init(struct trace_array *tr) |
81d68a96 | 546 | { |
e9d25fe6 SR |
547 | save_lat_flag = trace_flags & TRACE_ITER_LATENCY_FMT; |
548 | trace_flags |= TRACE_ITER_LATENCY_FMT; | |
549 | ||
745b1626 | 550 | tracing_max_latency = 0; |
81d68a96 | 551 | irqsoff_trace = tr; |
c5f888ca | 552 | /* make sure that the tracer is visible */ |
81d68a96 | 553 | smp_wmb(); |
2f26ebd5 | 554 | tracing_reset_online_cpus(tr); |
62b915f1 JO |
555 | |
556 | if (start_irqsoff_tracer(tr, is_graph())) | |
557 | printk(KERN_ERR "failed to start irqsoff tracer\n"); | |
81d68a96 SR |
558 | } |
559 | ||
560 | static void irqsoff_tracer_reset(struct trace_array *tr) | |
561 | { | |
62b915f1 | 562 | stop_irqsoff_tracer(tr, is_graph()); |
e9d25fe6 SR |
563 | |
564 | if (!save_lat_flag) | |
565 | trace_flags &= ~TRACE_ITER_LATENCY_FMT; | |
81d68a96 SR |
566 | } |
567 | ||
9036990d SR |
568 | static void irqsoff_tracer_start(struct trace_array *tr) |
569 | { | |
9036990d | 570 | tracer_enabled = 1; |
9036990d SR |
571 | } |
572 | ||
573 | static void irqsoff_tracer_stop(struct trace_array *tr) | |
574 | { | |
575 | tracer_enabled = 0; | |
81d68a96 SR |
576 | } |
577 | ||
6cd8a4bb | 578 | #ifdef CONFIG_IRQSOFF_TRACER |
1c80025a | 579 | static int irqsoff_tracer_init(struct trace_array *tr) |
6cd8a4bb SR |
580 | { |
581 | trace_type = TRACER_IRQS_OFF; | |
582 | ||
583 | __irqsoff_tracer_init(tr); | |
1c80025a | 584 | return 0; |
6cd8a4bb | 585 | } |
81d68a96 SR |
586 | static struct tracer irqsoff_tracer __read_mostly = |
587 | { | |
588 | .name = "irqsoff", | |
589 | .init = irqsoff_tracer_init, | |
590 | .reset = irqsoff_tracer_reset, | |
9036990d SR |
591 | .start = irqsoff_tracer_start, |
592 | .stop = irqsoff_tracer_stop, | |
81d68a96 | 593 | .print_max = 1, |
62b915f1 JO |
594 | .print_header = irqsoff_print_header, |
595 | .print_line = irqsoff_print_line, | |
596 | .flags = &tracer_flags, | |
597 | .set_flag = irqsoff_set_flag, | |
60a11774 SR |
598 | #ifdef CONFIG_FTRACE_SELFTEST |
599 | .selftest = trace_selftest_startup_irqsoff, | |
600 | #endif | |
62b915f1 JO |
601 | .open = irqsoff_trace_open, |
602 | .close = irqsoff_trace_close, | |
ef710e10 | 603 | .use_max_tr = 1, |
81d68a96 | 604 | }; |
6cd8a4bb SR |
605 | # define register_irqsoff(trace) register_tracer(&trace) |
606 | #else | |
607 | # define register_irqsoff(trace) do { } while (0) | |
608 | #endif | |
609 | ||
610 | #ifdef CONFIG_PREEMPT_TRACER | |
1c80025a | 611 | static int preemptoff_tracer_init(struct trace_array *tr) |
6cd8a4bb SR |
612 | { |
613 | trace_type = TRACER_PREEMPT_OFF; | |
614 | ||
615 | __irqsoff_tracer_init(tr); | |
1c80025a | 616 | return 0; |
6cd8a4bb SR |
617 | } |
618 | ||
619 | static struct tracer preemptoff_tracer __read_mostly = | |
620 | { | |
621 | .name = "preemptoff", | |
622 | .init = preemptoff_tracer_init, | |
623 | .reset = irqsoff_tracer_reset, | |
9036990d SR |
624 | .start = irqsoff_tracer_start, |
625 | .stop = irqsoff_tracer_stop, | |
6cd8a4bb | 626 | .print_max = 1, |
62b915f1 JO |
627 | .print_header = irqsoff_print_header, |
628 | .print_line = irqsoff_print_line, | |
629 | .flags = &tracer_flags, | |
630 | .set_flag = irqsoff_set_flag, | |
60a11774 SR |
631 | #ifdef CONFIG_FTRACE_SELFTEST |
632 | .selftest = trace_selftest_startup_preemptoff, | |
633 | #endif | |
62b915f1 JO |
634 | .open = irqsoff_trace_open, |
635 | .close = irqsoff_trace_close, | |
ef710e10 | 636 | .use_max_tr = 1, |
6cd8a4bb SR |
637 | }; |
638 | # define register_preemptoff(trace) register_tracer(&trace) | |
639 | #else | |
640 | # define register_preemptoff(trace) do { } while (0) | |
641 | #endif | |
642 | ||
643 | #if defined(CONFIG_IRQSOFF_TRACER) && \ | |
644 | defined(CONFIG_PREEMPT_TRACER) | |
645 | ||
1c80025a | 646 | static int preemptirqsoff_tracer_init(struct trace_array *tr) |
6cd8a4bb SR |
647 | { |
648 | trace_type = TRACER_IRQS_OFF | TRACER_PREEMPT_OFF; | |
649 | ||
650 | __irqsoff_tracer_init(tr); | |
1c80025a | 651 | return 0; |
6cd8a4bb SR |
652 | } |
653 | ||
654 | static struct tracer preemptirqsoff_tracer __read_mostly = | |
655 | { | |
656 | .name = "preemptirqsoff", | |
657 | .init = preemptirqsoff_tracer_init, | |
658 | .reset = irqsoff_tracer_reset, | |
9036990d SR |
659 | .start = irqsoff_tracer_start, |
660 | .stop = irqsoff_tracer_stop, | |
6cd8a4bb | 661 | .print_max = 1, |
62b915f1 JO |
662 | .print_header = irqsoff_print_header, |
663 | .print_line = irqsoff_print_line, | |
664 | .flags = &tracer_flags, | |
665 | .set_flag = irqsoff_set_flag, | |
60a11774 SR |
666 | #ifdef CONFIG_FTRACE_SELFTEST |
667 | .selftest = trace_selftest_startup_preemptirqsoff, | |
668 | #endif | |
62b915f1 JO |
669 | .open = irqsoff_trace_open, |
670 | .close = irqsoff_trace_close, | |
ef710e10 | 671 | .use_max_tr = 1, |
6cd8a4bb SR |
672 | }; |
673 | ||
674 | # define register_preemptirqsoff(trace) register_tracer(&trace) | |
675 | #else | |
676 | # define register_preemptirqsoff(trace) do { } while (0) | |
677 | #endif | |
81d68a96 SR |
678 | |
679 | __init static int init_irqsoff_tracer(void) | |
680 | { | |
6cd8a4bb SR |
681 | register_irqsoff(irqsoff_tracer); |
682 | register_preemptoff(preemptoff_tracer); | |
683 | register_preemptirqsoff(preemptirqsoff_tracer); | |
81d68a96 SR |
684 | |
685 | return 0; | |
686 | } | |
687 | device_initcall(init_irqsoff_tracer); |