Commit | Line | Data |
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1da177e4 LT |
1 | /** |
2 | * @file buffer_sync.c | |
3 | * | |
ae735e99 | 4 | * @remark Copyright 2002-2009 OProfile authors |
1da177e4 LT |
5 | * @remark Read the file COPYING |
6 | * | |
7 | * @author John Levon <levon@movementarian.org> | |
345c2573 | 8 | * @author Barry Kasindorf |
ae735e99 | 9 | * @author Robert Richter <robert.richter@amd.com> |
1da177e4 LT |
10 | * |
11 | * This is the core of the buffer management. Each | |
12 | * CPU buffer is processed and entered into the | |
13 | * global event buffer. Such processing is necessary | |
14 | * in several circumstances, mentioned below. | |
15 | * | |
16 | * The processing does the job of converting the | |
17 | * transitory EIP value into a persistent dentry/offset | |
18 | * value that the profiler can record at its leisure. | |
19 | * | |
20 | * See fs/dcookies.c for a description of the dentry/offset | |
21 | * objects. | |
22 | */ | |
23 | ||
24 | #include <linux/mm.h> | |
25 | #include <linux/workqueue.h> | |
26 | #include <linux/notifier.h> | |
27 | #include <linux/dcookies.h> | |
28 | #include <linux/profile.h> | |
29 | #include <linux/module.h> | |
30 | #include <linux/fs.h> | |
1474855d | 31 | #include <linux/oprofile.h> |
e8edc6e0 | 32 | #include <linux/sched.h> |
1474855d | 33 | |
1da177e4 LT |
34 | #include "oprofile_stats.h" |
35 | #include "event_buffer.h" | |
36 | #include "cpu_buffer.h" | |
37 | #include "buffer_sync.h" | |
73185e0a | 38 | |
1da177e4 LT |
39 | static LIST_HEAD(dying_tasks); |
40 | static LIST_HEAD(dead_tasks); | |
f7df8ed1 | 41 | static cpumask_var_t marked_cpus; |
1da177e4 LT |
42 | static DEFINE_SPINLOCK(task_mortuary); |
43 | static void process_task_mortuary(void); | |
44 | ||
1da177e4 LT |
45 | /* Take ownership of the task struct and place it on the |
46 | * list for processing. Only after two full buffer syncs | |
47 | * does the task eventually get freed, because by then | |
48 | * we are sure we will not reference it again. | |
4369ef3c PM |
49 | * Can be invoked from softirq via RCU callback due to |
50 | * call_rcu() of the task struct, hence the _irqsave. | |
1da177e4 | 51 | */ |
73185e0a RR |
52 | static int |
53 | task_free_notify(struct notifier_block *self, unsigned long val, void *data) | |
1da177e4 | 54 | { |
4369ef3c | 55 | unsigned long flags; |
73185e0a | 56 | struct task_struct *task = data; |
4369ef3c | 57 | spin_lock_irqsave(&task_mortuary, flags); |
1da177e4 | 58 | list_add(&task->tasks, &dying_tasks); |
4369ef3c | 59 | spin_unlock_irqrestore(&task_mortuary, flags); |
1da177e4 LT |
60 | return NOTIFY_OK; |
61 | } | |
62 | ||
63 | ||
64 | /* The task is on its way out. A sync of the buffer means we can catch | |
65 | * any remaining samples for this task. | |
66 | */ | |
73185e0a RR |
67 | static int |
68 | task_exit_notify(struct notifier_block *self, unsigned long val, void *data) | |
1da177e4 LT |
69 | { |
70 | /* To avoid latency problems, we only process the current CPU, | |
71 | * hoping that most samples for the task are on this CPU | |
72 | */ | |
39c715b7 | 73 | sync_buffer(raw_smp_processor_id()); |
73185e0a | 74 | return 0; |
1da177e4 LT |
75 | } |
76 | ||
77 | ||
78 | /* The task is about to try a do_munmap(). We peek at what it's going to | |
79 | * do, and if it's an executable region, process the samples first, so | |
80 | * we don't lose any. This does not have to be exact, it's a QoI issue | |
81 | * only. | |
82 | */ | |
73185e0a RR |
83 | static int |
84 | munmap_notify(struct notifier_block *self, unsigned long val, void *data) | |
1da177e4 LT |
85 | { |
86 | unsigned long addr = (unsigned long)data; | |
73185e0a RR |
87 | struct mm_struct *mm = current->mm; |
88 | struct vm_area_struct *mpnt; | |
1da177e4 LT |
89 | |
90 | down_read(&mm->mmap_sem); | |
91 | ||
92 | mpnt = find_vma(mm, addr); | |
93 | if (mpnt && mpnt->vm_file && (mpnt->vm_flags & VM_EXEC)) { | |
94 | up_read(&mm->mmap_sem); | |
95 | /* To avoid latency problems, we only process the current CPU, | |
96 | * hoping that most samples for the task are on this CPU | |
97 | */ | |
39c715b7 | 98 | sync_buffer(raw_smp_processor_id()); |
1da177e4 LT |
99 | return 0; |
100 | } | |
101 | ||
102 | up_read(&mm->mmap_sem); | |
103 | return 0; | |
104 | } | |
105 | ||
73185e0a | 106 | |
1da177e4 LT |
107 | /* We need to be told about new modules so we don't attribute to a previously |
108 | * loaded module, or drop the samples on the floor. | |
109 | */ | |
73185e0a RR |
110 | static int |
111 | module_load_notify(struct notifier_block *self, unsigned long val, void *data) | |
1da177e4 LT |
112 | { |
113 | #ifdef CONFIG_MODULES | |
114 | if (val != MODULE_STATE_COMING) | |
115 | return 0; | |
116 | ||
117 | /* FIXME: should we process all CPU buffers ? */ | |
59cc185a | 118 | mutex_lock(&buffer_mutex); |
1da177e4 LT |
119 | add_event_entry(ESCAPE_CODE); |
120 | add_event_entry(MODULE_LOADED_CODE); | |
59cc185a | 121 | mutex_unlock(&buffer_mutex); |
1da177e4 LT |
122 | #endif |
123 | return 0; | |
124 | } | |
125 | ||
73185e0a | 126 | |
1da177e4 LT |
127 | static struct notifier_block task_free_nb = { |
128 | .notifier_call = task_free_notify, | |
129 | }; | |
130 | ||
131 | static struct notifier_block task_exit_nb = { | |
132 | .notifier_call = task_exit_notify, | |
133 | }; | |
134 | ||
135 | static struct notifier_block munmap_nb = { | |
136 | .notifier_call = munmap_notify, | |
137 | }; | |
138 | ||
139 | static struct notifier_block module_load_nb = { | |
140 | .notifier_call = module_load_notify, | |
141 | }; | |
142 | ||
73185e0a | 143 | |
1da177e4 LT |
144 | static void end_sync(void) |
145 | { | |
146 | end_cpu_work(); | |
147 | /* make sure we don't leak task structs */ | |
148 | process_task_mortuary(); | |
149 | process_task_mortuary(); | |
150 | } | |
151 | ||
152 | ||
153 | int sync_start(void) | |
154 | { | |
155 | int err; | |
156 | ||
4c50d9ea RR |
157 | if (!alloc_cpumask_var(&marked_cpus, GFP_KERNEL)) |
158 | return -ENOMEM; | |
159 | cpumask_clear(marked_cpus); | |
160 | ||
1da177e4 LT |
161 | start_cpu_work(); |
162 | ||
163 | err = task_handoff_register(&task_free_nb); | |
164 | if (err) | |
165 | goto out1; | |
166 | err = profile_event_register(PROFILE_TASK_EXIT, &task_exit_nb); | |
167 | if (err) | |
168 | goto out2; | |
169 | err = profile_event_register(PROFILE_MUNMAP, &munmap_nb); | |
170 | if (err) | |
171 | goto out3; | |
172 | err = register_module_notifier(&module_load_nb); | |
173 | if (err) | |
174 | goto out4; | |
175 | ||
176 | out: | |
177 | return err; | |
178 | out4: | |
179 | profile_event_unregister(PROFILE_MUNMAP, &munmap_nb); | |
180 | out3: | |
181 | profile_event_unregister(PROFILE_TASK_EXIT, &task_exit_nb); | |
182 | out2: | |
183 | task_handoff_unregister(&task_free_nb); | |
184 | out1: | |
185 | end_sync(); | |
4c50d9ea | 186 | free_cpumask_var(marked_cpus); |
1da177e4 LT |
187 | goto out; |
188 | } | |
189 | ||
190 | ||
191 | void sync_stop(void) | |
192 | { | |
193 | unregister_module_notifier(&module_load_nb); | |
194 | profile_event_unregister(PROFILE_MUNMAP, &munmap_nb); | |
195 | profile_event_unregister(PROFILE_TASK_EXIT, &task_exit_nb); | |
196 | task_handoff_unregister(&task_free_nb); | |
197 | end_sync(); | |
4c50d9ea | 198 | free_cpumask_var(marked_cpus); |
1da177e4 LT |
199 | } |
200 | ||
448678a0 | 201 | |
1da177e4 LT |
202 | /* Optimisation. We can manage without taking the dcookie sem |
203 | * because we cannot reach this code without at least one | |
204 | * dcookie user still being registered (namely, the reader | |
205 | * of the event buffer). */ | |
448678a0 | 206 | static inline unsigned long fast_get_dcookie(struct path *path) |
1da177e4 LT |
207 | { |
208 | unsigned long cookie; | |
448678a0 | 209 | |
c2452f32 | 210 | if (path->dentry->d_flags & DCACHE_COOKIE) |
448678a0 JB |
211 | return (unsigned long)path->dentry; |
212 | get_dcookie(path, &cookie); | |
1da177e4 LT |
213 | return cookie; |
214 | } | |
215 | ||
448678a0 | 216 | |
1da177e4 LT |
217 | /* Look up the dcookie for the task's first VM_EXECUTABLE mapping, |
218 | * which corresponds loosely to "application name". This is | |
219 | * not strictly necessary but allows oprofile to associate | |
220 | * shared-library samples with particular applications | |
221 | */ | |
73185e0a | 222 | static unsigned long get_exec_dcookie(struct mm_struct *mm) |
1da177e4 | 223 | { |
0c0a400d | 224 | unsigned long cookie = NO_COOKIE; |
73185e0a RR |
225 | struct vm_area_struct *vma; |
226 | ||
1da177e4 LT |
227 | if (!mm) |
228 | goto out; | |
73185e0a | 229 | |
1da177e4 LT |
230 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
231 | if (!vma->vm_file) | |
232 | continue; | |
233 | if (!(vma->vm_flags & VM_EXECUTABLE)) | |
234 | continue; | |
448678a0 | 235 | cookie = fast_get_dcookie(&vma->vm_file->f_path); |
1da177e4 LT |
236 | break; |
237 | } | |
238 | ||
239 | out: | |
240 | return cookie; | |
241 | } | |
242 | ||
243 | ||
244 | /* Convert the EIP value of a sample into a persistent dentry/offset | |
245 | * pair that can then be added to the global event buffer. We make | |
246 | * sure to do this lookup before a mm->mmap modification happens so | |
247 | * we don't lose track. | |
248 | */ | |
73185e0a RR |
249 | static unsigned long |
250 | lookup_dcookie(struct mm_struct *mm, unsigned long addr, off_t *offset) | |
1da177e4 | 251 | { |
0c0a400d | 252 | unsigned long cookie = NO_COOKIE; |
73185e0a | 253 | struct vm_area_struct *vma; |
1da177e4 LT |
254 | |
255 | for (vma = find_vma(mm, addr); vma; vma = vma->vm_next) { | |
73185e0a | 256 | |
1da177e4 LT |
257 | if (addr < vma->vm_start || addr >= vma->vm_end) |
258 | continue; | |
259 | ||
0c0a400d | 260 | if (vma->vm_file) { |
448678a0 | 261 | cookie = fast_get_dcookie(&vma->vm_file->f_path); |
0c0a400d JL |
262 | *offset = (vma->vm_pgoff << PAGE_SHIFT) + addr - |
263 | vma->vm_start; | |
264 | } else { | |
265 | /* must be an anonymous map */ | |
266 | *offset = addr; | |
267 | } | |
268 | ||
1da177e4 LT |
269 | break; |
270 | } | |
271 | ||
0c0a400d JL |
272 | if (!vma) |
273 | cookie = INVALID_COOKIE; | |
274 | ||
1da177e4 LT |
275 | return cookie; |
276 | } | |
277 | ||
0c0a400d | 278 | static unsigned long last_cookie = INVALID_COOKIE; |
73185e0a | 279 | |
1da177e4 LT |
280 | static void add_cpu_switch(int i) |
281 | { | |
282 | add_event_entry(ESCAPE_CODE); | |
283 | add_event_entry(CPU_SWITCH_CODE); | |
284 | add_event_entry(i); | |
0c0a400d | 285 | last_cookie = INVALID_COOKIE; |
1da177e4 LT |
286 | } |
287 | ||
288 | static void add_kernel_ctx_switch(unsigned int in_kernel) | |
289 | { | |
290 | add_event_entry(ESCAPE_CODE); | |
291 | if (in_kernel) | |
73185e0a | 292 | add_event_entry(KERNEL_ENTER_SWITCH_CODE); |
1da177e4 | 293 | else |
73185e0a | 294 | add_event_entry(KERNEL_EXIT_SWITCH_CODE); |
1da177e4 | 295 | } |
73185e0a | 296 | |
1da177e4 | 297 | static void |
73185e0a | 298 | add_user_ctx_switch(struct task_struct const *task, unsigned long cookie) |
1da177e4 LT |
299 | { |
300 | add_event_entry(ESCAPE_CODE); | |
73185e0a | 301 | add_event_entry(CTX_SWITCH_CODE); |
1da177e4 LT |
302 | add_event_entry(task->pid); |
303 | add_event_entry(cookie); | |
304 | /* Another code for daemon back-compat */ | |
305 | add_event_entry(ESCAPE_CODE); | |
306 | add_event_entry(CTX_TGID_CODE); | |
307 | add_event_entry(task->tgid); | |
308 | } | |
309 | ||
73185e0a | 310 | |
1da177e4 LT |
311 | static void add_cookie_switch(unsigned long cookie) |
312 | { | |
313 | add_event_entry(ESCAPE_CODE); | |
314 | add_event_entry(COOKIE_SWITCH_CODE); | |
315 | add_event_entry(cookie); | |
316 | } | |
317 | ||
73185e0a | 318 | |
1da177e4 LT |
319 | static void add_trace_begin(void) |
320 | { | |
321 | add_event_entry(ESCAPE_CODE); | |
322 | add_event_entry(TRACE_BEGIN_CODE); | |
323 | } | |
324 | ||
1acda878 | 325 | static void add_data(struct op_entry *entry, struct mm_struct *mm) |
345c2573 | 326 | { |
1acda878 RR |
327 | unsigned long code, pc, val; |
328 | unsigned long cookie; | |
345c2573 | 329 | off_t offset; |
345c2573 | 330 | |
1acda878 RR |
331 | if (!op_cpu_buffer_get_data(entry, &code)) |
332 | return; | |
333 | if (!op_cpu_buffer_get_data(entry, &pc)) | |
334 | return; | |
335 | if (!op_cpu_buffer_get_size(entry)) | |
dbe6e283 | 336 | return; |
345c2573 BK |
337 | |
338 | if (mm) { | |
d358e75f | 339 | cookie = lookup_dcookie(mm, pc, &offset); |
345c2573 | 340 | |
d358e75f RR |
341 | if (cookie == NO_COOKIE) |
342 | offset = pc; | |
343 | if (cookie == INVALID_COOKIE) { | |
345c2573 | 344 | atomic_inc(&oprofile_stats.sample_lost_no_mapping); |
d358e75f | 345 | offset = pc; |
345c2573 | 346 | } |
d358e75f RR |
347 | if (cookie != last_cookie) { |
348 | add_cookie_switch(cookie); | |
349 | last_cookie = cookie; | |
345c2573 BK |
350 | } |
351 | } else | |
d358e75f | 352 | offset = pc; |
345c2573 BK |
353 | |
354 | add_event_entry(ESCAPE_CODE); | |
355 | add_event_entry(code); | |
356 | add_event_entry(offset); /* Offset from Dcookie */ | |
357 | ||
1acda878 RR |
358 | while (op_cpu_buffer_get_data(entry, &val)) |
359 | add_event_entry(val); | |
345c2573 | 360 | } |
1da177e4 | 361 | |
6368a1f4 | 362 | static inline void add_sample_entry(unsigned long offset, unsigned long event) |
1da177e4 LT |
363 | { |
364 | add_event_entry(offset); | |
365 | add_event_entry(event); | |
366 | } | |
367 | ||
368 | ||
9741b309 RR |
369 | /* |
370 | * Add a sample to the global event buffer. If possible the | |
371 | * sample is converted into a persistent dentry/offset pair | |
372 | * for later lookup from userspace. Return 0 on failure. | |
373 | */ | |
374 | static int | |
375 | add_sample(struct mm_struct *mm, struct op_sample *s, int in_kernel) | |
1da177e4 LT |
376 | { |
377 | unsigned long cookie; | |
378 | off_t offset; | |
73185e0a | 379 | |
9741b309 RR |
380 | if (in_kernel) { |
381 | add_sample_entry(s->eip, s->event); | |
382 | return 1; | |
383 | } | |
384 | ||
385 | /* add userspace sample */ | |
386 | ||
387 | if (!mm) { | |
388 | atomic_inc(&oprofile_stats.sample_lost_no_mm); | |
389 | return 0; | |
390 | } | |
391 | ||
73185e0a RR |
392 | cookie = lookup_dcookie(mm, s->eip, &offset); |
393 | ||
0c0a400d | 394 | if (cookie == INVALID_COOKIE) { |
1da177e4 LT |
395 | atomic_inc(&oprofile_stats.sample_lost_no_mapping); |
396 | return 0; | |
397 | } | |
398 | ||
399 | if (cookie != last_cookie) { | |
400 | add_cookie_switch(cookie); | |
401 | last_cookie = cookie; | |
402 | } | |
403 | ||
404 | add_sample_entry(offset, s->event); | |
405 | ||
406 | return 1; | |
407 | } | |
408 | ||
73185e0a | 409 | |
73185e0a | 410 | static void release_mm(struct mm_struct *mm) |
1da177e4 LT |
411 | { |
412 | if (!mm) | |
413 | return; | |
414 | up_read(&mm->mmap_sem); | |
415 | mmput(mm); | |
416 | } | |
417 | ||
418 | ||
73185e0a | 419 | static struct mm_struct *take_tasks_mm(struct task_struct *task) |
1da177e4 | 420 | { |
73185e0a | 421 | struct mm_struct *mm = get_task_mm(task); |
1da177e4 LT |
422 | if (mm) |
423 | down_read(&mm->mmap_sem); | |
424 | return mm; | |
425 | } | |
426 | ||
427 | ||
428 | static inline int is_code(unsigned long val) | |
429 | { | |
430 | return val == ESCAPE_CODE; | |
431 | } | |
73185e0a | 432 | |
1da177e4 | 433 | |
1da177e4 LT |
434 | /* Move tasks along towards death. Any tasks on dead_tasks |
435 | * will definitely have no remaining references in any | |
436 | * CPU buffers at this point, because we use two lists, | |
437 | * and to have reached the list, it must have gone through | |
438 | * one full sync already. | |
439 | */ | |
440 | static void process_task_mortuary(void) | |
441 | { | |
4369ef3c PM |
442 | unsigned long flags; |
443 | LIST_HEAD(local_dead_tasks); | |
73185e0a RR |
444 | struct task_struct *task; |
445 | struct task_struct *ttask; | |
1da177e4 | 446 | |
4369ef3c | 447 | spin_lock_irqsave(&task_mortuary, flags); |
1da177e4 | 448 | |
4369ef3c PM |
449 | list_splice_init(&dead_tasks, &local_dead_tasks); |
450 | list_splice_init(&dying_tasks, &dead_tasks); | |
1da177e4 | 451 | |
4369ef3c PM |
452 | spin_unlock_irqrestore(&task_mortuary, flags); |
453 | ||
454 | list_for_each_entry_safe(task, ttask, &local_dead_tasks, tasks) { | |
1da177e4 | 455 | list_del(&task->tasks); |
4369ef3c | 456 | free_task(task); |
1da177e4 | 457 | } |
1da177e4 LT |
458 | } |
459 | ||
460 | ||
461 | static void mark_done(int cpu) | |
462 | { | |
463 | int i; | |
464 | ||
f7df8ed1 | 465 | cpumask_set_cpu(cpu, marked_cpus); |
1da177e4 LT |
466 | |
467 | for_each_online_cpu(i) { | |
f7df8ed1 | 468 | if (!cpumask_test_cpu(i, marked_cpus)) |
1da177e4 LT |
469 | return; |
470 | } | |
471 | ||
472 | /* All CPUs have been processed at least once, | |
473 | * we can process the mortuary once | |
474 | */ | |
475 | process_task_mortuary(); | |
476 | ||
f7df8ed1 | 477 | cpumask_clear(marked_cpus); |
1da177e4 LT |
478 | } |
479 | ||
480 | ||
481 | /* FIXME: this is not sufficient if we implement syscall barrier backtrace | |
482 | * traversal, the code switch to sb_sample_start at first kernel enter/exit | |
483 | * switch so we need a fifth state and some special handling in sync_buffer() | |
484 | */ | |
485 | typedef enum { | |
486 | sb_bt_ignore = -2, | |
487 | sb_buffer_start, | |
488 | sb_bt_start, | |
489 | sb_sample_start, | |
490 | } sync_buffer_state; | |
491 | ||
492 | /* Sync one of the CPU's buffers into the global event buffer. | |
493 | * Here we need to go through each batch of samples punctuated | |
494 | * by context switch notes, taking the task's mmap_sem and doing | |
495 | * lookup in task->mm->mmap to convert EIP into dcookie/offset | |
496 | * value. | |
497 | */ | |
498 | void sync_buffer(int cpu) | |
499 | { | |
1da177e4 | 500 | struct mm_struct *mm = NULL; |
fd7826d5 | 501 | struct mm_struct *oldmm; |
bd7dc46f | 502 | unsigned long val; |
73185e0a | 503 | struct task_struct *new; |
1da177e4 LT |
504 | unsigned long cookie = 0; |
505 | int in_kernel = 1; | |
1da177e4 | 506 | sync_buffer_state state = sb_buffer_start; |
9b1f2611 | 507 | unsigned int i; |
1da177e4 | 508 | unsigned long available; |
ae735e99 | 509 | unsigned long flags; |
2d87b14c RR |
510 | struct op_entry entry; |
511 | struct op_sample *sample; | |
1da177e4 | 512 | |
59cc185a | 513 | mutex_lock(&buffer_mutex); |
73185e0a | 514 | |
1da177e4 LT |
515 | add_cpu_switch(cpu); |
516 | ||
6d2c53f3 RR |
517 | op_cpu_buffer_reset(cpu); |
518 | available = op_cpu_buffer_entries(cpu); | |
1da177e4 LT |
519 | |
520 | for (i = 0; i < available; ++i) { | |
2d87b14c RR |
521 | sample = op_cpu_buffer_read_entry(&entry, cpu); |
522 | if (!sample) | |
6dad828b | 523 | break; |
73185e0a | 524 | |
2d87b14c | 525 | if (is_code(sample->eip)) { |
ae735e99 RR |
526 | flags = sample->event; |
527 | if (flags & TRACE_BEGIN) { | |
528 | state = sb_bt_start; | |
529 | add_trace_begin(); | |
530 | } | |
531 | if (flags & KERNEL_CTX_SWITCH) { | |
1da177e4 | 532 | /* kernel/userspace switch */ |
ae735e99 | 533 | in_kernel = flags & IS_KERNEL; |
1da177e4 LT |
534 | if (state == sb_buffer_start) |
535 | state = sb_sample_start; | |
ae735e99 RR |
536 | add_kernel_ctx_switch(flags & IS_KERNEL); |
537 | } | |
bd7dc46f RR |
538 | if (flags & USER_CTX_SWITCH |
539 | && op_cpu_buffer_get_data(&entry, &val)) { | |
1da177e4 | 540 | /* userspace context switch */ |
bd7dc46f | 541 | new = (struct task_struct *)val; |
fd7826d5 | 542 | oldmm = mm; |
1da177e4 LT |
543 | release_mm(oldmm); |
544 | mm = take_tasks_mm(new); | |
545 | if (mm != oldmm) | |
546 | cookie = get_exec_dcookie(mm); | |
547 | add_user_ctx_switch(new, cookie); | |
1da177e4 | 548 | } |
1acda878 RR |
549 | if (op_cpu_buffer_get_size(&entry)) |
550 | add_data(&entry, mm); | |
317f33bc RR |
551 | continue; |
552 | } | |
553 | ||
554 | if (state < sb_bt_start) | |
555 | /* ignore sample */ | |
556 | continue; | |
557 | ||
2d87b14c | 558 | if (add_sample(mm, sample, in_kernel)) |
317f33bc RR |
559 | continue; |
560 | ||
561 | /* ignore backtraces if failed to add a sample */ | |
562 | if (state == sb_bt_start) { | |
563 | state = sb_bt_ignore; | |
564 | atomic_inc(&oprofile_stats.bt_lost_no_mapping); | |
1da177e4 | 565 | } |
1da177e4 LT |
566 | } |
567 | release_mm(mm); | |
568 | ||
569 | mark_done(cpu); | |
570 | ||
59cc185a | 571 | mutex_unlock(&buffer_mutex); |
1da177e4 | 572 | } |
a5598ca0 CL |
573 | |
574 | /* The function can be used to add a buffer worth of data directly to | |
575 | * the kernel buffer. The buffer is assumed to be a circular buffer. | |
576 | * Take the entries from index start and end at index end, wrapping | |
577 | * at max_entries. | |
578 | */ | |
579 | void oprofile_put_buff(unsigned long *buf, unsigned int start, | |
580 | unsigned int stop, unsigned int max) | |
581 | { | |
582 | int i; | |
583 | ||
584 | i = start; | |
585 | ||
586 | mutex_lock(&buffer_mutex); | |
587 | while (i != stop) { | |
588 | add_event_entry(buf[i++]); | |
589 | ||
590 | if (i >= max) | |
591 | i = 0; | |
592 | } | |
593 | ||
594 | mutex_unlock(&buffer_mutex); | |
595 | } | |
596 |