Commit | Line | Data |
---|---|---|
60a11774 SR |
1 | /* Include in trace.c */ |
2 | ||
9cc26a26 | 3 | #include <linux/stringify.h> |
60a11774 | 4 | #include <linux/kthread.h> |
c7aafc54 | 5 | #include <linux/delay.h> |
5a0e3ad6 | 6 | #include <linux/slab.h> |
60a11774 | 7 | |
e309b41d | 8 | static inline int trace_valid_entry(struct trace_entry *entry) |
60a11774 SR |
9 | { |
10 | switch (entry->type) { | |
11 | case TRACE_FN: | |
12 | case TRACE_CTX: | |
57422797 | 13 | case TRACE_WAKE: |
06fa75ab | 14 | case TRACE_STACK: |
dd0e545f | 15 | case TRACE_PRINT: |
80e5ea45 | 16 | case TRACE_BRANCH: |
7447dce9 FW |
17 | case TRACE_GRAPH_ENT: |
18 | case TRACE_GRAPH_RET: | |
60a11774 SR |
19 | return 1; |
20 | } | |
21 | return 0; | |
22 | } | |
23 | ||
3928a8a2 | 24 | static int trace_test_buffer_cpu(struct trace_array *tr, int cpu) |
60a11774 | 25 | { |
3928a8a2 SR |
26 | struct ring_buffer_event *event; |
27 | struct trace_entry *entry; | |
4b3e3d22 | 28 | unsigned int loops = 0; |
60a11774 | 29 | |
66a8cb95 | 30 | while ((event = ring_buffer_consume(tr->buffer, cpu, NULL, NULL))) { |
3928a8a2 | 31 | entry = ring_buffer_event_data(event); |
60a11774 | 32 | |
4b3e3d22 SR |
33 | /* |
34 | * The ring buffer is a size of trace_buf_size, if | |
35 | * we loop more than the size, there's something wrong | |
36 | * with the ring buffer. | |
37 | */ | |
38 | if (loops++ > trace_buf_size) { | |
39 | printk(KERN_CONT ".. bad ring buffer "); | |
40 | goto failed; | |
41 | } | |
3928a8a2 | 42 | if (!trace_valid_entry(entry)) { |
c7aafc54 | 43 | printk(KERN_CONT ".. invalid entry %d ", |
3928a8a2 | 44 | entry->type); |
60a11774 SR |
45 | goto failed; |
46 | } | |
60a11774 | 47 | } |
60a11774 SR |
48 | return 0; |
49 | ||
50 | failed: | |
08bafa0e SR |
51 | /* disable tracing */ |
52 | tracing_disabled = 1; | |
60a11774 SR |
53 | printk(KERN_CONT ".. corrupted trace buffer .. "); |
54 | return -1; | |
55 | } | |
56 | ||
57 | /* | |
58 | * Test the trace buffer to see if all the elements | |
59 | * are still sane. | |
60 | */ | |
61 | static int trace_test_buffer(struct trace_array *tr, unsigned long *count) | |
62 | { | |
30afdcb1 SR |
63 | unsigned long flags, cnt = 0; |
64 | int cpu, ret = 0; | |
60a11774 | 65 | |
30afdcb1 | 66 | /* Don't allow flipping of max traces now */ |
d51ad7ac | 67 | local_irq_save(flags); |
0199c4e6 | 68 | arch_spin_lock(&ftrace_max_lock); |
60a11774 | 69 | |
3928a8a2 | 70 | cnt = ring_buffer_entries(tr->buffer); |
60a11774 | 71 | |
0c5119c1 SR |
72 | /* |
73 | * The trace_test_buffer_cpu runs a while loop to consume all data. | |
74 | * If the calling tracer is broken, and is constantly filling | |
75 | * the buffer, this will run forever, and hard lock the box. | |
76 | * We disable the ring buffer while we do this test to prevent | |
77 | * a hard lock up. | |
78 | */ | |
79 | tracing_off(); | |
3928a8a2 SR |
80 | for_each_possible_cpu(cpu) { |
81 | ret = trace_test_buffer_cpu(tr, cpu); | |
60a11774 SR |
82 | if (ret) |
83 | break; | |
84 | } | |
0c5119c1 | 85 | tracing_on(); |
0199c4e6 | 86 | arch_spin_unlock(&ftrace_max_lock); |
d51ad7ac | 87 | local_irq_restore(flags); |
60a11774 SR |
88 | |
89 | if (count) | |
90 | *count = cnt; | |
91 | ||
92 | return ret; | |
93 | } | |
94 | ||
1c80025a FW |
95 | static inline void warn_failed_init_tracer(struct tracer *trace, int init_ret) |
96 | { | |
97 | printk(KERN_WARNING "Failed to init %s tracer, init returned %d\n", | |
98 | trace->name, init_ret); | |
99 | } | |
606576ce | 100 | #ifdef CONFIG_FUNCTION_TRACER |
77a2b37d SR |
101 | |
102 | #ifdef CONFIG_DYNAMIC_FTRACE | |
103 | ||
95950c2e SR |
104 | static int trace_selftest_test_probe1_cnt; |
105 | static void trace_selftest_test_probe1_func(unsigned long ip, | |
2f5f6ad9 | 106 | unsigned long pip, |
a1e2e31d SR |
107 | struct ftrace_ops *op, |
108 | struct pt_regs *pt_regs) | |
95950c2e SR |
109 | { |
110 | trace_selftest_test_probe1_cnt++; | |
111 | } | |
112 | ||
113 | static int trace_selftest_test_probe2_cnt; | |
114 | static void trace_selftest_test_probe2_func(unsigned long ip, | |
2f5f6ad9 | 115 | unsigned long pip, |
a1e2e31d SR |
116 | struct ftrace_ops *op, |
117 | struct pt_regs *pt_regs) | |
95950c2e SR |
118 | { |
119 | trace_selftest_test_probe2_cnt++; | |
120 | } | |
121 | ||
122 | static int trace_selftest_test_probe3_cnt; | |
123 | static void trace_selftest_test_probe3_func(unsigned long ip, | |
2f5f6ad9 | 124 | unsigned long pip, |
a1e2e31d SR |
125 | struct ftrace_ops *op, |
126 | struct pt_regs *pt_regs) | |
95950c2e SR |
127 | { |
128 | trace_selftest_test_probe3_cnt++; | |
129 | } | |
130 | ||
131 | static int trace_selftest_test_global_cnt; | |
132 | static void trace_selftest_test_global_func(unsigned long ip, | |
2f5f6ad9 | 133 | unsigned long pip, |
a1e2e31d SR |
134 | struct ftrace_ops *op, |
135 | struct pt_regs *pt_regs) | |
95950c2e SR |
136 | { |
137 | trace_selftest_test_global_cnt++; | |
138 | } | |
139 | ||
140 | static int trace_selftest_test_dyn_cnt; | |
141 | static void trace_selftest_test_dyn_func(unsigned long ip, | |
2f5f6ad9 | 142 | unsigned long pip, |
a1e2e31d SR |
143 | struct ftrace_ops *op, |
144 | struct pt_regs *pt_regs) | |
95950c2e SR |
145 | { |
146 | trace_selftest_test_dyn_cnt++; | |
147 | } | |
148 | ||
149 | static struct ftrace_ops test_probe1 = { | |
150 | .func = trace_selftest_test_probe1_func, | |
4740974a | 151 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
95950c2e SR |
152 | }; |
153 | ||
154 | static struct ftrace_ops test_probe2 = { | |
155 | .func = trace_selftest_test_probe2_func, | |
4740974a | 156 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
95950c2e SR |
157 | }; |
158 | ||
159 | static struct ftrace_ops test_probe3 = { | |
160 | .func = trace_selftest_test_probe3_func, | |
4740974a | 161 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, |
95950c2e SR |
162 | }; |
163 | ||
164 | static struct ftrace_ops test_global = { | |
4740974a SR |
165 | .func = trace_selftest_test_global_func, |
166 | .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE, | |
95950c2e SR |
167 | }; |
168 | ||
169 | static void print_counts(void) | |
170 | { | |
171 | printk("(%d %d %d %d %d) ", | |
172 | trace_selftest_test_probe1_cnt, | |
173 | trace_selftest_test_probe2_cnt, | |
174 | trace_selftest_test_probe3_cnt, | |
175 | trace_selftest_test_global_cnt, | |
176 | trace_selftest_test_dyn_cnt); | |
177 | } | |
178 | ||
179 | static void reset_counts(void) | |
180 | { | |
181 | trace_selftest_test_probe1_cnt = 0; | |
182 | trace_selftest_test_probe2_cnt = 0; | |
183 | trace_selftest_test_probe3_cnt = 0; | |
184 | trace_selftest_test_global_cnt = 0; | |
185 | trace_selftest_test_dyn_cnt = 0; | |
186 | } | |
187 | ||
188 | static int trace_selftest_ops(int cnt) | |
189 | { | |
190 | int save_ftrace_enabled = ftrace_enabled; | |
191 | struct ftrace_ops *dyn_ops; | |
192 | char *func1_name; | |
193 | char *func2_name; | |
194 | int len1; | |
195 | int len2; | |
196 | int ret = -1; | |
197 | ||
198 | printk(KERN_CONT "PASSED\n"); | |
199 | pr_info("Testing dynamic ftrace ops #%d: ", cnt); | |
200 | ||
201 | ftrace_enabled = 1; | |
202 | reset_counts(); | |
203 | ||
204 | /* Handle PPC64 '.' name */ | |
205 | func1_name = "*" __stringify(DYN_FTRACE_TEST_NAME); | |
206 | func2_name = "*" __stringify(DYN_FTRACE_TEST_NAME2); | |
207 | len1 = strlen(func1_name); | |
208 | len2 = strlen(func2_name); | |
209 | ||
210 | /* | |
211 | * Probe 1 will trace function 1. | |
212 | * Probe 2 will trace function 2. | |
213 | * Probe 3 will trace functions 1 and 2. | |
214 | */ | |
215 | ftrace_set_filter(&test_probe1, func1_name, len1, 1); | |
216 | ftrace_set_filter(&test_probe2, func2_name, len2, 1); | |
217 | ftrace_set_filter(&test_probe3, func1_name, len1, 1); | |
218 | ftrace_set_filter(&test_probe3, func2_name, len2, 0); | |
219 | ||
220 | register_ftrace_function(&test_probe1); | |
221 | register_ftrace_function(&test_probe2); | |
222 | register_ftrace_function(&test_probe3); | |
223 | register_ftrace_function(&test_global); | |
224 | ||
225 | DYN_FTRACE_TEST_NAME(); | |
226 | ||
227 | print_counts(); | |
228 | ||
229 | if (trace_selftest_test_probe1_cnt != 1) | |
230 | goto out; | |
231 | if (trace_selftest_test_probe2_cnt != 0) | |
232 | goto out; | |
233 | if (trace_selftest_test_probe3_cnt != 1) | |
234 | goto out; | |
235 | if (trace_selftest_test_global_cnt == 0) | |
236 | goto out; | |
237 | ||
238 | DYN_FTRACE_TEST_NAME2(); | |
239 | ||
240 | print_counts(); | |
241 | ||
242 | if (trace_selftest_test_probe1_cnt != 1) | |
243 | goto out; | |
244 | if (trace_selftest_test_probe2_cnt != 1) | |
245 | goto out; | |
246 | if (trace_selftest_test_probe3_cnt != 2) | |
247 | goto out; | |
248 | ||
249 | /* Add a dynamic probe */ | |
250 | dyn_ops = kzalloc(sizeof(*dyn_ops), GFP_KERNEL); | |
251 | if (!dyn_ops) { | |
252 | printk("MEMORY ERROR "); | |
253 | goto out; | |
254 | } | |
255 | ||
256 | dyn_ops->func = trace_selftest_test_dyn_func; | |
257 | ||
258 | register_ftrace_function(dyn_ops); | |
259 | ||
260 | trace_selftest_test_global_cnt = 0; | |
261 | ||
262 | DYN_FTRACE_TEST_NAME(); | |
263 | ||
264 | print_counts(); | |
265 | ||
266 | if (trace_selftest_test_probe1_cnt != 2) | |
267 | goto out_free; | |
268 | if (trace_selftest_test_probe2_cnt != 1) | |
269 | goto out_free; | |
270 | if (trace_selftest_test_probe3_cnt != 3) | |
271 | goto out_free; | |
272 | if (trace_selftest_test_global_cnt == 0) | |
273 | goto out; | |
274 | if (trace_selftest_test_dyn_cnt == 0) | |
275 | goto out_free; | |
276 | ||
277 | DYN_FTRACE_TEST_NAME2(); | |
278 | ||
279 | print_counts(); | |
280 | ||
281 | if (trace_selftest_test_probe1_cnt != 2) | |
282 | goto out_free; | |
283 | if (trace_selftest_test_probe2_cnt != 2) | |
284 | goto out_free; | |
285 | if (trace_selftest_test_probe3_cnt != 4) | |
286 | goto out_free; | |
287 | ||
288 | ret = 0; | |
289 | out_free: | |
290 | unregister_ftrace_function(dyn_ops); | |
291 | kfree(dyn_ops); | |
292 | ||
293 | out: | |
294 | /* Purposely unregister in the same order */ | |
295 | unregister_ftrace_function(&test_probe1); | |
296 | unregister_ftrace_function(&test_probe2); | |
297 | unregister_ftrace_function(&test_probe3); | |
298 | unregister_ftrace_function(&test_global); | |
299 | ||
300 | /* Make sure everything is off */ | |
301 | reset_counts(); | |
302 | DYN_FTRACE_TEST_NAME(); | |
303 | DYN_FTRACE_TEST_NAME(); | |
304 | ||
305 | if (trace_selftest_test_probe1_cnt || | |
306 | trace_selftest_test_probe2_cnt || | |
307 | trace_selftest_test_probe3_cnt || | |
308 | trace_selftest_test_global_cnt || | |
309 | trace_selftest_test_dyn_cnt) | |
310 | ret = -1; | |
311 | ||
312 | ftrace_enabled = save_ftrace_enabled; | |
313 | ||
314 | return ret; | |
315 | } | |
316 | ||
77a2b37d SR |
317 | /* Test dynamic code modification and ftrace filters */ |
318 | int trace_selftest_startup_dynamic_tracing(struct tracer *trace, | |
319 | struct trace_array *tr, | |
320 | int (*func)(void)) | |
321 | { | |
77a2b37d | 322 | int save_ftrace_enabled = ftrace_enabled; |
dd0e545f | 323 | unsigned long count; |
4e491d14 | 324 | char *func_name; |
dd0e545f | 325 | int ret; |
77a2b37d SR |
326 | |
327 | /* The ftrace test PASSED */ | |
328 | printk(KERN_CONT "PASSED\n"); | |
329 | pr_info("Testing dynamic ftrace: "); | |
330 | ||
331 | /* enable tracing, and record the filter function */ | |
332 | ftrace_enabled = 1; | |
77a2b37d SR |
333 | |
334 | /* passed in by parameter to fool gcc from optimizing */ | |
335 | func(); | |
336 | ||
4e491d14 | 337 | /* |
73d8b8bc | 338 | * Some archs *cough*PowerPC*cough* add characters to the |
4e491d14 | 339 | * start of the function names. We simply put a '*' to |
73d8b8bc | 340 | * accommodate them. |
4e491d14 | 341 | */ |
9cc26a26 | 342 | func_name = "*" __stringify(DYN_FTRACE_TEST_NAME); |
4e491d14 | 343 | |
77a2b37d | 344 | /* filter only on our function */ |
936e074b | 345 | ftrace_set_global_filter(func_name, strlen(func_name), 1); |
77a2b37d SR |
346 | |
347 | /* enable tracing */ | |
b6f11df2 | 348 | ret = tracer_init(trace, tr); |
1c80025a FW |
349 | if (ret) { |
350 | warn_failed_init_tracer(trace, ret); | |
351 | goto out; | |
352 | } | |
dd0e545f | 353 | |
77a2b37d SR |
354 | /* Sleep for a 1/10 of a second */ |
355 | msleep(100); | |
356 | ||
357 | /* we should have nothing in the buffer */ | |
358 | ret = trace_test_buffer(tr, &count); | |
359 | if (ret) | |
360 | goto out; | |
361 | ||
362 | if (count) { | |
363 | ret = -1; | |
364 | printk(KERN_CONT ".. filter did not filter .. "); | |
365 | goto out; | |
366 | } | |
367 | ||
368 | /* call our function again */ | |
369 | func(); | |
370 | ||
371 | /* sleep again */ | |
372 | msleep(100); | |
373 | ||
374 | /* stop the tracing. */ | |
bbf5b1a0 | 375 | tracing_stop(); |
77a2b37d SR |
376 | ftrace_enabled = 0; |
377 | ||
378 | /* check the trace buffer */ | |
379 | ret = trace_test_buffer(tr, &count); | |
bbf5b1a0 | 380 | tracing_start(); |
77a2b37d SR |
381 | |
382 | /* we should only have one item */ | |
383 | if (!ret && count != 1) { | |
95950c2e | 384 | trace->reset(tr); |
06fa75ab | 385 | printk(KERN_CONT ".. filter failed count=%ld ..", count); |
77a2b37d SR |
386 | ret = -1; |
387 | goto out; | |
388 | } | |
bbf5b1a0 | 389 | |
95950c2e SR |
390 | /* Test the ops with global tracing running */ |
391 | ret = trace_selftest_ops(1); | |
392 | trace->reset(tr); | |
393 | ||
77a2b37d SR |
394 | out: |
395 | ftrace_enabled = save_ftrace_enabled; | |
77a2b37d SR |
396 | |
397 | /* Enable tracing on all functions again */ | |
936e074b | 398 | ftrace_set_global_filter(NULL, 0, 1); |
77a2b37d | 399 | |
95950c2e SR |
400 | /* Test the ops with global tracing off */ |
401 | if (!ret) | |
402 | ret = trace_selftest_ops(2); | |
403 | ||
77a2b37d SR |
404 | return ret; |
405 | } | |
ea701f11 SR |
406 | |
407 | static int trace_selftest_recursion_cnt; | |
408 | static void trace_selftest_test_recursion_func(unsigned long ip, | |
409 | unsigned long pip, | |
410 | struct ftrace_ops *op, | |
411 | struct pt_regs *pt_regs) | |
412 | { | |
413 | /* | |
414 | * This function is registered without the recursion safe flag. | |
415 | * The ftrace infrastructure should provide the recursion | |
416 | * protection. If not, this will crash the kernel! | |
417 | */ | |
9640388b SR |
418 | if (trace_selftest_recursion_cnt++ > 10) |
419 | return; | |
ea701f11 SR |
420 | DYN_FTRACE_TEST_NAME(); |
421 | } | |
422 | ||
423 | static void trace_selftest_test_recursion_safe_func(unsigned long ip, | |
424 | unsigned long pip, | |
425 | struct ftrace_ops *op, | |
426 | struct pt_regs *pt_regs) | |
427 | { | |
428 | /* | |
429 | * We said we would provide our own recursion. By calling | |
430 | * this function again, we should recurse back into this function | |
431 | * and count again. But this only happens if the arch supports | |
432 | * all of ftrace features and nothing else is using the function | |
433 | * tracing utility. | |
434 | */ | |
435 | if (trace_selftest_recursion_cnt++) | |
436 | return; | |
437 | DYN_FTRACE_TEST_NAME(); | |
438 | } | |
439 | ||
440 | static struct ftrace_ops test_rec_probe = { | |
441 | .func = trace_selftest_test_recursion_func, | |
442 | }; | |
443 | ||
444 | static struct ftrace_ops test_recsafe_probe = { | |
445 | .func = trace_selftest_test_recursion_safe_func, | |
446 | .flags = FTRACE_OPS_FL_RECURSION_SAFE, | |
447 | }; | |
448 | ||
449 | static int | |
450 | trace_selftest_function_recursion(void) | |
451 | { | |
452 | int save_ftrace_enabled = ftrace_enabled; | |
ea701f11 SR |
453 | char *func_name; |
454 | int len; | |
455 | int ret; | |
ea701f11 SR |
456 | |
457 | /* The previous test PASSED */ | |
458 | pr_cont("PASSED\n"); | |
459 | pr_info("Testing ftrace recursion: "); | |
460 | ||
461 | ||
462 | /* enable tracing, and record the filter function */ | |
463 | ftrace_enabled = 1; | |
ea701f11 SR |
464 | |
465 | /* Handle PPC64 '.' name */ | |
466 | func_name = "*" __stringify(DYN_FTRACE_TEST_NAME); | |
467 | len = strlen(func_name); | |
468 | ||
469 | ret = ftrace_set_filter(&test_rec_probe, func_name, len, 1); | |
470 | if (ret) { | |
471 | pr_cont("*Could not set filter* "); | |
472 | goto out; | |
473 | } | |
474 | ||
475 | ret = register_ftrace_function(&test_rec_probe); | |
476 | if (ret) { | |
477 | pr_cont("*could not register callback* "); | |
478 | goto out; | |
479 | } | |
480 | ||
481 | DYN_FTRACE_TEST_NAME(); | |
482 | ||
483 | unregister_ftrace_function(&test_rec_probe); | |
484 | ||
485 | ret = -1; | |
486 | if (trace_selftest_recursion_cnt != 1) { | |
487 | pr_cont("*callback not called once (%d)* ", | |
488 | trace_selftest_recursion_cnt); | |
489 | goto out; | |
490 | } | |
491 | ||
492 | trace_selftest_recursion_cnt = 1; | |
493 | ||
494 | pr_cont("PASSED\n"); | |
495 | pr_info("Testing ftrace recursion safe: "); | |
496 | ||
497 | ret = ftrace_set_filter(&test_recsafe_probe, func_name, len, 1); | |
498 | if (ret) { | |
499 | pr_cont("*Could not set filter* "); | |
500 | goto out; | |
501 | } | |
502 | ||
503 | ret = register_ftrace_function(&test_recsafe_probe); | |
504 | if (ret) { | |
505 | pr_cont("*could not register callback* "); | |
506 | goto out; | |
507 | } | |
508 | ||
509 | DYN_FTRACE_TEST_NAME(); | |
510 | ||
511 | unregister_ftrace_function(&test_recsafe_probe); | |
512 | ||
ea701f11 | 513 | ret = -1; |
05cbbf64 SR |
514 | if (trace_selftest_recursion_cnt != 2) { |
515 | pr_cont("*callback not called expected 2 times (%d)* ", | |
516 | trace_selftest_recursion_cnt); | |
ea701f11 SR |
517 | goto out; |
518 | } | |
519 | ||
520 | ret = 0; | |
521 | out: | |
522 | ftrace_enabled = save_ftrace_enabled; | |
ea701f11 SR |
523 | |
524 | return ret; | |
525 | } | |
77a2b37d SR |
526 | #else |
527 | # define trace_selftest_startup_dynamic_tracing(trace, tr, func) ({ 0; }) | |
ea701f11 | 528 | # define trace_selftest_function_recursion() ({ 0; }) |
77a2b37d | 529 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
e9a22d1f | 530 | |
ad97772a SR |
531 | static enum { |
532 | TRACE_SELFTEST_REGS_START, | |
533 | TRACE_SELFTEST_REGS_FOUND, | |
534 | TRACE_SELFTEST_REGS_NOT_FOUND, | |
535 | } trace_selftest_regs_stat; | |
536 | ||
537 | static void trace_selftest_test_regs_func(unsigned long ip, | |
538 | unsigned long pip, | |
539 | struct ftrace_ops *op, | |
540 | struct pt_regs *pt_regs) | |
541 | { | |
542 | if (pt_regs) | |
543 | trace_selftest_regs_stat = TRACE_SELFTEST_REGS_FOUND; | |
544 | else | |
545 | trace_selftest_regs_stat = TRACE_SELFTEST_REGS_NOT_FOUND; | |
546 | } | |
547 | ||
548 | static struct ftrace_ops test_regs_probe = { | |
549 | .func = trace_selftest_test_regs_func, | |
550 | .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_SAVE_REGS, | |
551 | }; | |
552 | ||
553 | static int | |
554 | trace_selftest_function_regs(void) | |
555 | { | |
556 | int save_ftrace_enabled = ftrace_enabled; | |
ad97772a SR |
557 | char *func_name; |
558 | int len; | |
559 | int ret; | |
560 | int supported = 0; | |
561 | ||
06aeaaea | 562 | #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS |
ad97772a SR |
563 | supported = 1; |
564 | #endif | |
565 | ||
566 | /* The previous test PASSED */ | |
567 | pr_cont("PASSED\n"); | |
568 | pr_info("Testing ftrace regs%s: ", | |
569 | !supported ? "(no arch support)" : ""); | |
570 | ||
571 | /* enable tracing, and record the filter function */ | |
572 | ftrace_enabled = 1; | |
ad97772a SR |
573 | |
574 | /* Handle PPC64 '.' name */ | |
575 | func_name = "*" __stringify(DYN_FTRACE_TEST_NAME); | |
576 | len = strlen(func_name); | |
577 | ||
578 | ret = ftrace_set_filter(&test_regs_probe, func_name, len, 1); | |
579 | /* | |
580 | * If DYNAMIC_FTRACE is not set, then we just trace all functions. | |
581 | * This test really doesn't care. | |
582 | */ | |
583 | if (ret && ret != -ENODEV) { | |
584 | pr_cont("*Could not set filter* "); | |
585 | goto out; | |
586 | } | |
587 | ||
588 | ret = register_ftrace_function(&test_regs_probe); | |
589 | /* | |
590 | * Now if the arch does not support passing regs, then this should | |
591 | * have failed. | |
592 | */ | |
593 | if (!supported) { | |
594 | if (!ret) { | |
595 | pr_cont("*registered save-regs without arch support* "); | |
596 | goto out; | |
597 | } | |
598 | test_regs_probe.flags |= FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED; | |
599 | ret = register_ftrace_function(&test_regs_probe); | |
600 | } | |
601 | if (ret) { | |
602 | pr_cont("*could not register callback* "); | |
603 | goto out; | |
604 | } | |
605 | ||
606 | ||
607 | DYN_FTRACE_TEST_NAME(); | |
608 | ||
609 | unregister_ftrace_function(&test_regs_probe); | |
610 | ||
611 | ret = -1; | |
612 | ||
613 | switch (trace_selftest_regs_stat) { | |
614 | case TRACE_SELFTEST_REGS_START: | |
615 | pr_cont("*callback never called* "); | |
616 | goto out; | |
617 | ||
618 | case TRACE_SELFTEST_REGS_FOUND: | |
619 | if (supported) | |
620 | break; | |
621 | pr_cont("*callback received regs without arch support* "); | |
622 | goto out; | |
623 | ||
624 | case TRACE_SELFTEST_REGS_NOT_FOUND: | |
625 | if (!supported) | |
626 | break; | |
627 | pr_cont("*callback received NULL regs* "); | |
628 | goto out; | |
629 | } | |
630 | ||
631 | ret = 0; | |
632 | out: | |
633 | ftrace_enabled = save_ftrace_enabled; | |
ad97772a SR |
634 | |
635 | return ret; | |
636 | } | |
637 | ||
60a11774 SR |
638 | /* |
639 | * Simple verification test of ftrace function tracer. | |
640 | * Enable ftrace, sleep 1/10 second, and then read the trace | |
641 | * buffer to see if all is in order. | |
642 | */ | |
643 | int | |
644 | trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr) | |
645 | { | |
77a2b37d | 646 | int save_ftrace_enabled = ftrace_enabled; |
dd0e545f SR |
647 | unsigned long count; |
648 | int ret; | |
60a11774 | 649 | |
77a2b37d SR |
650 | /* make sure msleep has been recorded */ |
651 | msleep(1); | |
652 | ||
60a11774 | 653 | /* start the tracing */ |
c7aafc54 IM |
654 | ftrace_enabled = 1; |
655 | ||
b6f11df2 | 656 | ret = tracer_init(trace, tr); |
1c80025a FW |
657 | if (ret) { |
658 | warn_failed_init_tracer(trace, ret); | |
659 | goto out; | |
660 | } | |
661 | ||
60a11774 SR |
662 | /* Sleep for a 1/10 of a second */ |
663 | msleep(100); | |
664 | /* stop the tracing. */ | |
bbf5b1a0 | 665 | tracing_stop(); |
c7aafc54 IM |
666 | ftrace_enabled = 0; |
667 | ||
60a11774 SR |
668 | /* check the trace buffer */ |
669 | ret = trace_test_buffer(tr, &count); | |
670 | trace->reset(tr); | |
bbf5b1a0 | 671 | tracing_start(); |
60a11774 SR |
672 | |
673 | if (!ret && !count) { | |
674 | printk(KERN_CONT ".. no entries found .."); | |
675 | ret = -1; | |
77a2b37d | 676 | goto out; |
60a11774 SR |
677 | } |
678 | ||
77a2b37d SR |
679 | ret = trace_selftest_startup_dynamic_tracing(trace, tr, |
680 | DYN_FTRACE_TEST_NAME); | |
ea701f11 SR |
681 | if (ret) |
682 | goto out; | |
77a2b37d | 683 | |
ea701f11 | 684 | ret = trace_selftest_function_recursion(); |
ad97772a SR |
685 | if (ret) |
686 | goto out; | |
687 | ||
688 | ret = trace_selftest_function_regs(); | |
77a2b37d SR |
689 | out: |
690 | ftrace_enabled = save_ftrace_enabled; | |
77a2b37d | 691 | |
4eebcc81 SR |
692 | /* kill ftrace totally if we failed */ |
693 | if (ret) | |
694 | ftrace_kill(); | |
695 | ||
60a11774 SR |
696 | return ret; |
697 | } | |
606576ce | 698 | #endif /* CONFIG_FUNCTION_TRACER */ |
60a11774 | 699 | |
7447dce9 FW |
700 | |
701 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
cf586b61 FW |
702 | |
703 | /* Maximum number of functions to trace before diagnosing a hang */ | |
704 | #define GRAPH_MAX_FUNC_TEST 100000000 | |
705 | ||
cecbca96 FW |
706 | static void |
707 | __ftrace_dump(bool disable_tracing, enum ftrace_dump_mode oops_dump_mode); | |
cf586b61 FW |
708 | static unsigned int graph_hang_thresh; |
709 | ||
710 | /* Wrap the real function entry probe to avoid possible hanging */ | |
711 | static int trace_graph_entry_watchdog(struct ftrace_graph_ent *trace) | |
712 | { | |
713 | /* This is harmlessly racy, we want to approximately detect a hang */ | |
714 | if (unlikely(++graph_hang_thresh > GRAPH_MAX_FUNC_TEST)) { | |
715 | ftrace_graph_stop(); | |
716 | printk(KERN_WARNING "BUG: Function graph tracer hang!\n"); | |
717 | if (ftrace_dump_on_oops) | |
cecbca96 | 718 | __ftrace_dump(false, DUMP_ALL); |
cf586b61 FW |
719 | return 0; |
720 | } | |
721 | ||
722 | return trace_graph_entry(trace); | |
723 | } | |
724 | ||
7447dce9 FW |
725 | /* |
726 | * Pretty much the same than for the function tracer from which the selftest | |
727 | * has been borrowed. | |
728 | */ | |
729 | int | |
730 | trace_selftest_startup_function_graph(struct tracer *trace, | |
731 | struct trace_array *tr) | |
732 | { | |
733 | int ret; | |
734 | unsigned long count; | |
735 | ||
cf586b61 FW |
736 | /* |
737 | * Simulate the init() callback but we attach a watchdog callback | |
738 | * to detect and recover from possible hangs | |
739 | */ | |
740 | tracing_reset_online_cpus(tr); | |
1a0799a8 | 741 | set_graph_array(tr); |
cf586b61 FW |
742 | ret = register_ftrace_graph(&trace_graph_return, |
743 | &trace_graph_entry_watchdog); | |
7447dce9 FW |
744 | if (ret) { |
745 | warn_failed_init_tracer(trace, ret); | |
746 | goto out; | |
747 | } | |
cf586b61 | 748 | tracing_start_cmdline_record(); |
7447dce9 FW |
749 | |
750 | /* Sleep for a 1/10 of a second */ | |
751 | msleep(100); | |
752 | ||
cf586b61 FW |
753 | /* Have we just recovered from a hang? */ |
754 | if (graph_hang_thresh > GRAPH_MAX_FUNC_TEST) { | |
0cf53ff6 | 755 | tracing_selftest_disabled = true; |
cf586b61 FW |
756 | ret = -1; |
757 | goto out; | |
758 | } | |
759 | ||
7447dce9 FW |
760 | tracing_stop(); |
761 | ||
762 | /* check the trace buffer */ | |
763 | ret = trace_test_buffer(tr, &count); | |
764 | ||
765 | trace->reset(tr); | |
766 | tracing_start(); | |
767 | ||
768 | if (!ret && !count) { | |
769 | printk(KERN_CONT ".. no entries found .."); | |
770 | ret = -1; | |
771 | goto out; | |
772 | } | |
773 | ||
774 | /* Don't test dynamic tracing, the function tracer already did */ | |
775 | ||
776 | out: | |
777 | /* Stop it if we failed */ | |
778 | if (ret) | |
779 | ftrace_graph_stop(); | |
780 | ||
781 | return ret; | |
782 | } | |
783 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ | |
784 | ||
785 | ||
60a11774 SR |
786 | #ifdef CONFIG_IRQSOFF_TRACER |
787 | int | |
788 | trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr) | |
789 | { | |
790 | unsigned long save_max = tracing_max_latency; | |
791 | unsigned long count; | |
792 | int ret; | |
793 | ||
794 | /* start the tracing */ | |
b6f11df2 | 795 | ret = tracer_init(trace, tr); |
1c80025a FW |
796 | if (ret) { |
797 | warn_failed_init_tracer(trace, ret); | |
798 | return ret; | |
799 | } | |
800 | ||
60a11774 SR |
801 | /* reset the max latency */ |
802 | tracing_max_latency = 0; | |
803 | /* disable interrupts for a bit */ | |
804 | local_irq_disable(); | |
805 | udelay(100); | |
806 | local_irq_enable(); | |
49036200 FW |
807 | |
808 | /* | |
809 | * Stop the tracer to avoid a warning subsequent | |
810 | * to buffer flipping failure because tracing_stop() | |
811 | * disables the tr and max buffers, making flipping impossible | |
812 | * in case of parallels max irqs off latencies. | |
813 | */ | |
814 | trace->stop(tr); | |
60a11774 | 815 | /* stop the tracing. */ |
bbf5b1a0 | 816 | tracing_stop(); |
60a11774 SR |
817 | /* check both trace buffers */ |
818 | ret = trace_test_buffer(tr, NULL); | |
819 | if (!ret) | |
820 | ret = trace_test_buffer(&max_tr, &count); | |
821 | trace->reset(tr); | |
bbf5b1a0 | 822 | tracing_start(); |
60a11774 SR |
823 | |
824 | if (!ret && !count) { | |
825 | printk(KERN_CONT ".. no entries found .."); | |
826 | ret = -1; | |
827 | } | |
828 | ||
829 | tracing_max_latency = save_max; | |
830 | ||
831 | return ret; | |
832 | } | |
833 | #endif /* CONFIG_IRQSOFF_TRACER */ | |
834 | ||
835 | #ifdef CONFIG_PREEMPT_TRACER | |
836 | int | |
837 | trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr) | |
838 | { | |
839 | unsigned long save_max = tracing_max_latency; | |
840 | unsigned long count; | |
841 | int ret; | |
842 | ||
769c48eb SR |
843 | /* |
844 | * Now that the big kernel lock is no longer preemptable, | |
845 | * and this is called with the BKL held, it will always | |
846 | * fail. If preemption is already disabled, simply | |
847 | * pass the test. When the BKL is removed, or becomes | |
848 | * preemptible again, we will once again test this, | |
849 | * so keep it in. | |
850 | */ | |
851 | if (preempt_count()) { | |
852 | printk(KERN_CONT "can not test ... force "); | |
853 | return 0; | |
854 | } | |
855 | ||
60a11774 | 856 | /* start the tracing */ |
b6f11df2 | 857 | ret = tracer_init(trace, tr); |
1c80025a FW |
858 | if (ret) { |
859 | warn_failed_init_tracer(trace, ret); | |
860 | return ret; | |
861 | } | |
862 | ||
60a11774 SR |
863 | /* reset the max latency */ |
864 | tracing_max_latency = 0; | |
865 | /* disable preemption for a bit */ | |
866 | preempt_disable(); | |
867 | udelay(100); | |
868 | preempt_enable(); | |
49036200 FW |
869 | |
870 | /* | |
871 | * Stop the tracer to avoid a warning subsequent | |
872 | * to buffer flipping failure because tracing_stop() | |
873 | * disables the tr and max buffers, making flipping impossible | |
874 | * in case of parallels max preempt off latencies. | |
875 | */ | |
876 | trace->stop(tr); | |
60a11774 | 877 | /* stop the tracing. */ |
bbf5b1a0 | 878 | tracing_stop(); |
60a11774 SR |
879 | /* check both trace buffers */ |
880 | ret = trace_test_buffer(tr, NULL); | |
881 | if (!ret) | |
882 | ret = trace_test_buffer(&max_tr, &count); | |
883 | trace->reset(tr); | |
bbf5b1a0 | 884 | tracing_start(); |
60a11774 SR |
885 | |
886 | if (!ret && !count) { | |
887 | printk(KERN_CONT ".. no entries found .."); | |
888 | ret = -1; | |
889 | } | |
890 | ||
891 | tracing_max_latency = save_max; | |
892 | ||
893 | return ret; | |
894 | } | |
895 | #endif /* CONFIG_PREEMPT_TRACER */ | |
896 | ||
897 | #if defined(CONFIG_IRQSOFF_TRACER) && defined(CONFIG_PREEMPT_TRACER) | |
898 | int | |
899 | trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *tr) | |
900 | { | |
901 | unsigned long save_max = tracing_max_latency; | |
902 | unsigned long count; | |
903 | int ret; | |
904 | ||
769c48eb SR |
905 | /* |
906 | * Now that the big kernel lock is no longer preemptable, | |
907 | * and this is called with the BKL held, it will always | |
908 | * fail. If preemption is already disabled, simply | |
909 | * pass the test. When the BKL is removed, or becomes | |
910 | * preemptible again, we will once again test this, | |
911 | * so keep it in. | |
912 | */ | |
913 | if (preempt_count()) { | |
914 | printk(KERN_CONT "can not test ... force "); | |
915 | return 0; | |
916 | } | |
917 | ||
60a11774 | 918 | /* start the tracing */ |
b6f11df2 | 919 | ret = tracer_init(trace, tr); |
1c80025a FW |
920 | if (ret) { |
921 | warn_failed_init_tracer(trace, ret); | |
ac1d52d0 | 922 | goto out_no_start; |
1c80025a | 923 | } |
60a11774 SR |
924 | |
925 | /* reset the max latency */ | |
926 | tracing_max_latency = 0; | |
927 | ||
928 | /* disable preemption and interrupts for a bit */ | |
929 | preempt_disable(); | |
930 | local_irq_disable(); | |
931 | udelay(100); | |
932 | preempt_enable(); | |
933 | /* reverse the order of preempt vs irqs */ | |
934 | local_irq_enable(); | |
935 | ||
49036200 FW |
936 | /* |
937 | * Stop the tracer to avoid a warning subsequent | |
938 | * to buffer flipping failure because tracing_stop() | |
939 | * disables the tr and max buffers, making flipping impossible | |
940 | * in case of parallels max irqs/preempt off latencies. | |
941 | */ | |
942 | trace->stop(tr); | |
60a11774 | 943 | /* stop the tracing. */ |
bbf5b1a0 | 944 | tracing_stop(); |
60a11774 SR |
945 | /* check both trace buffers */ |
946 | ret = trace_test_buffer(tr, NULL); | |
ac1d52d0 | 947 | if (ret) |
60a11774 SR |
948 | goto out; |
949 | ||
950 | ret = trace_test_buffer(&max_tr, &count); | |
ac1d52d0 | 951 | if (ret) |
60a11774 SR |
952 | goto out; |
953 | ||
954 | if (!ret && !count) { | |
955 | printk(KERN_CONT ".. no entries found .."); | |
956 | ret = -1; | |
957 | goto out; | |
958 | } | |
959 | ||
960 | /* do the test by disabling interrupts first this time */ | |
961 | tracing_max_latency = 0; | |
bbf5b1a0 | 962 | tracing_start(); |
49036200 FW |
963 | trace->start(tr); |
964 | ||
60a11774 SR |
965 | preempt_disable(); |
966 | local_irq_disable(); | |
967 | udelay(100); | |
968 | preempt_enable(); | |
969 | /* reverse the order of preempt vs irqs */ | |
970 | local_irq_enable(); | |
971 | ||
49036200 | 972 | trace->stop(tr); |
60a11774 | 973 | /* stop the tracing. */ |
bbf5b1a0 | 974 | tracing_stop(); |
60a11774 SR |
975 | /* check both trace buffers */ |
976 | ret = trace_test_buffer(tr, NULL); | |
977 | if (ret) | |
978 | goto out; | |
979 | ||
980 | ret = trace_test_buffer(&max_tr, &count); | |
981 | ||
982 | if (!ret && !count) { | |
983 | printk(KERN_CONT ".. no entries found .."); | |
984 | ret = -1; | |
985 | goto out; | |
986 | } | |
987 | ||
ac1d52d0 | 988 | out: |
bbf5b1a0 | 989 | tracing_start(); |
ac1d52d0 FW |
990 | out_no_start: |
991 | trace->reset(tr); | |
60a11774 SR |
992 | tracing_max_latency = save_max; |
993 | ||
994 | return ret; | |
995 | } | |
996 | #endif /* CONFIG_IRQSOFF_TRACER && CONFIG_PREEMPT_TRACER */ | |
997 | ||
fb1b6d8b SN |
998 | #ifdef CONFIG_NOP_TRACER |
999 | int | |
1000 | trace_selftest_startup_nop(struct tracer *trace, struct trace_array *tr) | |
1001 | { | |
1002 | /* What could possibly go wrong? */ | |
1003 | return 0; | |
1004 | } | |
1005 | #endif | |
1006 | ||
60a11774 SR |
1007 | #ifdef CONFIG_SCHED_TRACER |
1008 | static int trace_wakeup_test_thread(void *data) | |
1009 | { | |
60a11774 | 1010 | /* Make this a RT thread, doesn't need to be too high */ |
c9b5f501 | 1011 | static const struct sched_param param = { .sched_priority = 5 }; |
05bd68c5 | 1012 | struct completion *x = data; |
60a11774 | 1013 | |
05bd68c5 | 1014 | sched_setscheduler(current, SCHED_FIFO, ¶m); |
60a11774 SR |
1015 | |
1016 | /* Make it know we have a new prio */ | |
1017 | complete(x); | |
1018 | ||
1019 | /* now go to sleep and let the test wake us up */ | |
1020 | set_current_state(TASK_INTERRUPTIBLE); | |
1021 | schedule(); | |
1022 | ||
3c18c10b SR |
1023 | complete(x); |
1024 | ||
60a11774 SR |
1025 | /* we are awake, now wait to disappear */ |
1026 | while (!kthread_should_stop()) { | |
1027 | /* | |
1028 | * This is an RT task, do short sleeps to let | |
1029 | * others run. | |
1030 | */ | |
1031 | msleep(100); | |
1032 | } | |
1033 | ||
1034 | return 0; | |
1035 | } | |
1036 | ||
1037 | int | |
1038 | trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr) | |
1039 | { | |
1040 | unsigned long save_max = tracing_max_latency; | |
1041 | struct task_struct *p; | |
1042 | struct completion isrt; | |
1043 | unsigned long count; | |
1044 | int ret; | |
1045 | ||
1046 | init_completion(&isrt); | |
1047 | ||
1048 | /* create a high prio thread */ | |
1049 | p = kthread_run(trace_wakeup_test_thread, &isrt, "ftrace-test"); | |
c7aafc54 | 1050 | if (IS_ERR(p)) { |
60a11774 SR |
1051 | printk(KERN_CONT "Failed to create ftrace wakeup test thread "); |
1052 | return -1; | |
1053 | } | |
1054 | ||
1055 | /* make sure the thread is running at an RT prio */ | |
1056 | wait_for_completion(&isrt); | |
1057 | ||
1058 | /* start the tracing */ | |
b6f11df2 | 1059 | ret = tracer_init(trace, tr); |
1c80025a FW |
1060 | if (ret) { |
1061 | warn_failed_init_tracer(trace, ret); | |
1062 | return ret; | |
1063 | } | |
1064 | ||
60a11774 SR |
1065 | /* reset the max latency */ |
1066 | tracing_max_latency = 0; | |
1067 | ||
3c18c10b SR |
1068 | while (p->on_rq) { |
1069 | /* | |
1070 | * Sleep to make sure the RT thread is asleep too. | |
1071 | * On virtual machines we can't rely on timings, | |
1072 | * but we want to make sure this test still works. | |
1073 | */ | |
1074 | msleep(100); | |
1075 | } | |
60a11774 | 1076 | |
3c18c10b | 1077 | init_completion(&isrt); |
60a11774 SR |
1078 | |
1079 | wake_up_process(p); | |
1080 | ||
3c18c10b SR |
1081 | /* Wait for the task to wake up */ |
1082 | wait_for_completion(&isrt); | |
5aa60c60 | 1083 | |
60a11774 | 1084 | /* stop the tracing. */ |
bbf5b1a0 | 1085 | tracing_stop(); |
60a11774 SR |
1086 | /* check both trace buffers */ |
1087 | ret = trace_test_buffer(tr, NULL); | |
0d5c6e1c | 1088 | printk("ret = %d\n", ret); |
60a11774 SR |
1089 | if (!ret) |
1090 | ret = trace_test_buffer(&max_tr, &count); | |
1091 | ||
1092 | ||
1093 | trace->reset(tr); | |
bbf5b1a0 | 1094 | tracing_start(); |
60a11774 SR |
1095 | |
1096 | tracing_max_latency = save_max; | |
1097 | ||
1098 | /* kill the thread */ | |
1099 | kthread_stop(p); | |
1100 | ||
1101 | if (!ret && !count) { | |
1102 | printk(KERN_CONT ".. no entries found .."); | |
1103 | ret = -1; | |
1104 | } | |
1105 | ||
1106 | return ret; | |
1107 | } | |
1108 | #endif /* CONFIG_SCHED_TRACER */ | |
1109 | ||
1110 | #ifdef CONFIG_CONTEXT_SWITCH_TRACER | |
1111 | int | |
1112 | trace_selftest_startup_sched_switch(struct tracer *trace, struct trace_array *tr) | |
1113 | { | |
1114 | unsigned long count; | |
1115 | int ret; | |
1116 | ||
1117 | /* start the tracing */ | |
b6f11df2 | 1118 | ret = tracer_init(trace, tr); |
1c80025a FW |
1119 | if (ret) { |
1120 | warn_failed_init_tracer(trace, ret); | |
1121 | return ret; | |
1122 | } | |
1123 | ||
60a11774 SR |
1124 | /* Sleep for a 1/10 of a second */ |
1125 | msleep(100); | |
1126 | /* stop the tracing. */ | |
bbf5b1a0 | 1127 | tracing_stop(); |
60a11774 SR |
1128 | /* check the trace buffer */ |
1129 | ret = trace_test_buffer(tr, &count); | |
1130 | trace->reset(tr); | |
bbf5b1a0 | 1131 | tracing_start(); |
60a11774 SR |
1132 | |
1133 | if (!ret && !count) { | |
1134 | printk(KERN_CONT ".. no entries found .."); | |
1135 | ret = -1; | |
1136 | } | |
1137 | ||
1138 | return ret; | |
1139 | } | |
1140 | #endif /* CONFIG_CONTEXT_SWITCH_TRACER */ | |
a6dd24f8 | 1141 | |
80e5ea45 SR |
1142 | #ifdef CONFIG_BRANCH_TRACER |
1143 | int | |
1144 | trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr) | |
1145 | { | |
1146 | unsigned long count; | |
1147 | int ret; | |
1148 | ||
1149 | /* start the tracing */ | |
b6f11df2 | 1150 | ret = tracer_init(trace, tr); |
1c80025a FW |
1151 | if (ret) { |
1152 | warn_failed_init_tracer(trace, ret); | |
1153 | return ret; | |
1154 | } | |
1155 | ||
80e5ea45 SR |
1156 | /* Sleep for a 1/10 of a second */ |
1157 | msleep(100); | |
1158 | /* stop the tracing. */ | |
1159 | tracing_stop(); | |
1160 | /* check the trace buffer */ | |
1161 | ret = trace_test_buffer(tr, &count); | |
1162 | trace->reset(tr); | |
1163 | tracing_start(); | |
1164 | ||
d2ef7c2f WH |
1165 | if (!ret && !count) { |
1166 | printk(KERN_CONT ".. no entries found .."); | |
1167 | ret = -1; | |
1168 | } | |
1169 | ||
80e5ea45 SR |
1170 | return ret; |
1171 | } | |
1172 | #endif /* CONFIG_BRANCH_TRACER */ | |
321bb5e1 | 1173 |