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 | ||
79f55997 | 157 | if (!zalloc_cpumask_var(&marked_cpus, GFP_KERNEL)) |
4c50d9ea | 158 | return -ENOMEM; |
4c50d9ea | 159 | |
1da177e4 LT |
160 | start_cpu_work(); |
161 | ||
162 | err = task_handoff_register(&task_free_nb); | |
163 | if (err) | |
164 | goto out1; | |
165 | err = profile_event_register(PROFILE_TASK_EXIT, &task_exit_nb); | |
166 | if (err) | |
167 | goto out2; | |
168 | err = profile_event_register(PROFILE_MUNMAP, &munmap_nb); | |
169 | if (err) | |
170 | goto out3; | |
171 | err = register_module_notifier(&module_load_nb); | |
172 | if (err) | |
173 | goto out4; | |
174 | ||
175 | out: | |
176 | return err; | |
177 | out4: | |
178 | profile_event_unregister(PROFILE_MUNMAP, &munmap_nb); | |
179 | out3: | |
180 | profile_event_unregister(PROFILE_TASK_EXIT, &task_exit_nb); | |
181 | out2: | |
182 | task_handoff_unregister(&task_free_nb); | |
183 | out1: | |
184 | end_sync(); | |
4c50d9ea | 185 | free_cpumask_var(marked_cpus); |
1da177e4 LT |
186 | goto out; |
187 | } | |
188 | ||
189 | ||
190 | void sync_stop(void) | |
191 | { | |
192 | unregister_module_notifier(&module_load_nb); | |
193 | profile_event_unregister(PROFILE_MUNMAP, &munmap_nb); | |
194 | profile_event_unregister(PROFILE_TASK_EXIT, &task_exit_nb); | |
195 | task_handoff_unregister(&task_free_nb); | |
196 | end_sync(); | |
4c50d9ea | 197 | free_cpumask_var(marked_cpus); |
1da177e4 LT |
198 | } |
199 | ||
448678a0 | 200 | |
1da177e4 LT |
201 | /* Optimisation. We can manage without taking the dcookie sem |
202 | * because we cannot reach this code without at least one | |
203 | * dcookie user still being registered (namely, the reader | |
204 | * of the event buffer). */ | |
448678a0 | 205 | static inline unsigned long fast_get_dcookie(struct path *path) |
1da177e4 LT |
206 | { |
207 | unsigned long cookie; | |
448678a0 | 208 | |
c2452f32 | 209 | if (path->dentry->d_flags & DCACHE_COOKIE) |
448678a0 JB |
210 | return (unsigned long)path->dentry; |
211 | get_dcookie(path, &cookie); | |
1da177e4 LT |
212 | return cookie; |
213 | } | |
214 | ||
448678a0 | 215 | |
1da177e4 LT |
216 | /* Look up the dcookie for the task's first VM_EXECUTABLE mapping, |
217 | * which corresponds loosely to "application name". This is | |
218 | * not strictly necessary but allows oprofile to associate | |
219 | * shared-library samples with particular applications | |
220 | */ | |
73185e0a | 221 | static unsigned long get_exec_dcookie(struct mm_struct *mm) |
1da177e4 | 222 | { |
0c0a400d | 223 | unsigned long cookie = NO_COOKIE; |
73185e0a RR |
224 | struct vm_area_struct *vma; |
225 | ||
1da177e4 LT |
226 | if (!mm) |
227 | goto out; | |
73185e0a | 228 | |
1da177e4 LT |
229 | for (vma = mm->mmap; vma; vma = vma->vm_next) { |
230 | if (!vma->vm_file) | |
231 | continue; | |
232 | if (!(vma->vm_flags & VM_EXECUTABLE)) | |
233 | continue; | |
448678a0 | 234 | cookie = fast_get_dcookie(&vma->vm_file->f_path); |
1da177e4 LT |
235 | break; |
236 | } | |
237 | ||
238 | out: | |
239 | return cookie; | |
240 | } | |
241 | ||
242 | ||
243 | /* Convert the EIP value of a sample into a persistent dentry/offset | |
244 | * pair that can then be added to the global event buffer. We make | |
245 | * sure to do this lookup before a mm->mmap modification happens so | |
246 | * we don't lose track. | |
247 | */ | |
73185e0a RR |
248 | static unsigned long |
249 | lookup_dcookie(struct mm_struct *mm, unsigned long addr, off_t *offset) | |
1da177e4 | 250 | { |
0c0a400d | 251 | unsigned long cookie = NO_COOKIE; |
73185e0a | 252 | struct vm_area_struct *vma; |
1da177e4 LT |
253 | |
254 | for (vma = find_vma(mm, addr); vma; vma = vma->vm_next) { | |
73185e0a | 255 | |
1da177e4 LT |
256 | if (addr < vma->vm_start || addr >= vma->vm_end) |
257 | continue; | |
258 | ||
0c0a400d | 259 | if (vma->vm_file) { |
448678a0 | 260 | cookie = fast_get_dcookie(&vma->vm_file->f_path); |
0c0a400d JL |
261 | *offset = (vma->vm_pgoff << PAGE_SHIFT) + addr - |
262 | vma->vm_start; | |
263 | } else { | |
264 | /* must be an anonymous map */ | |
265 | *offset = addr; | |
266 | } | |
267 | ||
1da177e4 LT |
268 | break; |
269 | } | |
270 | ||
0c0a400d JL |
271 | if (!vma) |
272 | cookie = INVALID_COOKIE; | |
273 | ||
1da177e4 LT |
274 | return cookie; |
275 | } | |
276 | ||
0c0a400d | 277 | static unsigned long last_cookie = INVALID_COOKIE; |
73185e0a | 278 | |
1da177e4 LT |
279 | static void add_cpu_switch(int i) |
280 | { | |
281 | add_event_entry(ESCAPE_CODE); | |
282 | add_event_entry(CPU_SWITCH_CODE); | |
283 | add_event_entry(i); | |
0c0a400d | 284 | last_cookie = INVALID_COOKIE; |
1da177e4 LT |
285 | } |
286 | ||
287 | static void add_kernel_ctx_switch(unsigned int in_kernel) | |
288 | { | |
289 | add_event_entry(ESCAPE_CODE); | |
290 | if (in_kernel) | |
73185e0a | 291 | add_event_entry(KERNEL_ENTER_SWITCH_CODE); |
1da177e4 | 292 | else |
73185e0a | 293 | add_event_entry(KERNEL_EXIT_SWITCH_CODE); |
1da177e4 | 294 | } |
73185e0a | 295 | |
1da177e4 | 296 | static void |
73185e0a | 297 | add_user_ctx_switch(struct task_struct const *task, unsigned long cookie) |
1da177e4 LT |
298 | { |
299 | add_event_entry(ESCAPE_CODE); | |
73185e0a | 300 | add_event_entry(CTX_SWITCH_CODE); |
1da177e4 LT |
301 | add_event_entry(task->pid); |
302 | add_event_entry(cookie); | |
303 | /* Another code for daemon back-compat */ | |
304 | add_event_entry(ESCAPE_CODE); | |
305 | add_event_entry(CTX_TGID_CODE); | |
306 | add_event_entry(task->tgid); | |
307 | } | |
308 | ||
73185e0a | 309 | |
1da177e4 LT |
310 | static void add_cookie_switch(unsigned long cookie) |
311 | { | |
312 | add_event_entry(ESCAPE_CODE); | |
313 | add_event_entry(COOKIE_SWITCH_CODE); | |
314 | add_event_entry(cookie); | |
315 | } | |
316 | ||
73185e0a | 317 | |
1da177e4 LT |
318 | static void add_trace_begin(void) |
319 | { | |
320 | add_event_entry(ESCAPE_CODE); | |
321 | add_event_entry(TRACE_BEGIN_CODE); | |
322 | } | |
323 | ||
1acda878 | 324 | static void add_data(struct op_entry *entry, struct mm_struct *mm) |
345c2573 | 325 | { |
1acda878 RR |
326 | unsigned long code, pc, val; |
327 | unsigned long cookie; | |
345c2573 | 328 | off_t offset; |
345c2573 | 329 | |
1acda878 RR |
330 | if (!op_cpu_buffer_get_data(entry, &code)) |
331 | return; | |
332 | if (!op_cpu_buffer_get_data(entry, &pc)) | |
333 | return; | |
334 | if (!op_cpu_buffer_get_size(entry)) | |
dbe6e283 | 335 | return; |
345c2573 BK |
336 | |
337 | if (mm) { | |
d358e75f | 338 | cookie = lookup_dcookie(mm, pc, &offset); |
345c2573 | 339 | |
d358e75f RR |
340 | if (cookie == NO_COOKIE) |
341 | offset = pc; | |
342 | if (cookie == INVALID_COOKIE) { | |
345c2573 | 343 | atomic_inc(&oprofile_stats.sample_lost_no_mapping); |
d358e75f | 344 | offset = pc; |
345c2573 | 345 | } |
d358e75f RR |
346 | if (cookie != last_cookie) { |
347 | add_cookie_switch(cookie); | |
348 | last_cookie = cookie; | |
345c2573 BK |
349 | } |
350 | } else | |
d358e75f | 351 | offset = pc; |
345c2573 BK |
352 | |
353 | add_event_entry(ESCAPE_CODE); | |
354 | add_event_entry(code); | |
355 | add_event_entry(offset); /* Offset from Dcookie */ | |
356 | ||
1acda878 RR |
357 | while (op_cpu_buffer_get_data(entry, &val)) |
358 | add_event_entry(val); | |
345c2573 | 359 | } |
1da177e4 | 360 | |
6368a1f4 | 361 | static inline void add_sample_entry(unsigned long offset, unsigned long event) |
1da177e4 LT |
362 | { |
363 | add_event_entry(offset); | |
364 | add_event_entry(event); | |
365 | } | |
366 | ||
367 | ||
9741b309 RR |
368 | /* |
369 | * Add a sample to the global event buffer. If possible the | |
370 | * sample is converted into a persistent dentry/offset pair | |
371 | * for later lookup from userspace. Return 0 on failure. | |
372 | */ | |
373 | static int | |
374 | add_sample(struct mm_struct *mm, struct op_sample *s, int in_kernel) | |
1da177e4 LT |
375 | { |
376 | unsigned long cookie; | |
377 | off_t offset; | |
73185e0a | 378 | |
9741b309 RR |
379 | if (in_kernel) { |
380 | add_sample_entry(s->eip, s->event); | |
381 | return 1; | |
382 | } | |
383 | ||
384 | /* add userspace sample */ | |
385 | ||
386 | if (!mm) { | |
387 | atomic_inc(&oprofile_stats.sample_lost_no_mm); | |
388 | return 0; | |
389 | } | |
390 | ||
73185e0a RR |
391 | cookie = lookup_dcookie(mm, s->eip, &offset); |
392 | ||
0c0a400d | 393 | if (cookie == INVALID_COOKIE) { |
1da177e4 LT |
394 | atomic_inc(&oprofile_stats.sample_lost_no_mapping); |
395 | return 0; | |
396 | } | |
397 | ||
398 | if (cookie != last_cookie) { | |
399 | add_cookie_switch(cookie); | |
400 | last_cookie = cookie; | |
401 | } | |
402 | ||
403 | add_sample_entry(offset, s->event); | |
404 | ||
405 | return 1; | |
406 | } | |
407 | ||
73185e0a | 408 | |
73185e0a | 409 | static void release_mm(struct mm_struct *mm) |
1da177e4 LT |
410 | { |
411 | if (!mm) | |
412 | return; | |
413 | up_read(&mm->mmap_sem); | |
414 | mmput(mm); | |
415 | } | |
416 | ||
417 | ||
73185e0a | 418 | static struct mm_struct *take_tasks_mm(struct task_struct *task) |
1da177e4 | 419 | { |
73185e0a | 420 | struct mm_struct *mm = get_task_mm(task); |
1da177e4 LT |
421 | if (mm) |
422 | down_read(&mm->mmap_sem); | |
423 | return mm; | |
424 | } | |
425 | ||
426 | ||
427 | static inline int is_code(unsigned long val) | |
428 | { | |
429 | return val == ESCAPE_CODE; | |
430 | } | |
73185e0a | 431 | |
1da177e4 | 432 | |
1da177e4 LT |
433 | /* Move tasks along towards death. Any tasks on dead_tasks |
434 | * will definitely have no remaining references in any | |
435 | * CPU buffers at this point, because we use two lists, | |
436 | * and to have reached the list, it must have gone through | |
437 | * one full sync already. | |
438 | */ | |
439 | static void process_task_mortuary(void) | |
440 | { | |
4369ef3c PM |
441 | unsigned long flags; |
442 | LIST_HEAD(local_dead_tasks); | |
73185e0a RR |
443 | struct task_struct *task; |
444 | struct task_struct *ttask; | |
1da177e4 | 445 | |
4369ef3c | 446 | spin_lock_irqsave(&task_mortuary, flags); |
1da177e4 | 447 | |
4369ef3c PM |
448 | list_splice_init(&dead_tasks, &local_dead_tasks); |
449 | list_splice_init(&dying_tasks, &dead_tasks); | |
1da177e4 | 450 | |
4369ef3c PM |
451 | spin_unlock_irqrestore(&task_mortuary, flags); |
452 | ||
453 | list_for_each_entry_safe(task, ttask, &local_dead_tasks, tasks) { | |
1da177e4 | 454 | list_del(&task->tasks); |
4369ef3c | 455 | free_task(task); |
1da177e4 | 456 | } |
1da177e4 LT |
457 | } |
458 | ||
459 | ||
460 | static void mark_done(int cpu) | |
461 | { | |
462 | int i; | |
463 | ||
f7df8ed1 | 464 | cpumask_set_cpu(cpu, marked_cpus); |
1da177e4 LT |
465 | |
466 | for_each_online_cpu(i) { | |
f7df8ed1 | 467 | if (!cpumask_test_cpu(i, marked_cpus)) |
1da177e4 LT |
468 | return; |
469 | } | |
470 | ||
471 | /* All CPUs have been processed at least once, | |
472 | * we can process the mortuary once | |
473 | */ | |
474 | process_task_mortuary(); | |
475 | ||
f7df8ed1 | 476 | cpumask_clear(marked_cpus); |
1da177e4 LT |
477 | } |
478 | ||
479 | ||
480 | /* FIXME: this is not sufficient if we implement syscall barrier backtrace | |
481 | * traversal, the code switch to sb_sample_start at first kernel enter/exit | |
482 | * switch so we need a fifth state and some special handling in sync_buffer() | |
483 | */ | |
484 | typedef enum { | |
485 | sb_bt_ignore = -2, | |
486 | sb_buffer_start, | |
487 | sb_bt_start, | |
488 | sb_sample_start, | |
489 | } sync_buffer_state; | |
490 | ||
491 | /* Sync one of the CPU's buffers into the global event buffer. | |
492 | * Here we need to go through each batch of samples punctuated | |
493 | * by context switch notes, taking the task's mmap_sem and doing | |
494 | * lookup in task->mm->mmap to convert EIP into dcookie/offset | |
495 | * value. | |
496 | */ | |
497 | void sync_buffer(int cpu) | |
498 | { | |
1da177e4 | 499 | struct mm_struct *mm = NULL; |
fd7826d5 | 500 | struct mm_struct *oldmm; |
bd7dc46f | 501 | unsigned long val; |
73185e0a | 502 | struct task_struct *new; |
1da177e4 LT |
503 | unsigned long cookie = 0; |
504 | int in_kernel = 1; | |
1da177e4 | 505 | sync_buffer_state state = sb_buffer_start; |
9b1f2611 | 506 | unsigned int i; |
1da177e4 | 507 | unsigned long available; |
ae735e99 | 508 | unsigned long flags; |
2d87b14c RR |
509 | struct op_entry entry; |
510 | struct op_sample *sample; | |
1da177e4 | 511 | |
59cc185a | 512 | mutex_lock(&buffer_mutex); |
73185e0a | 513 | |
1da177e4 LT |
514 | add_cpu_switch(cpu); |
515 | ||
6d2c53f3 RR |
516 | op_cpu_buffer_reset(cpu); |
517 | available = op_cpu_buffer_entries(cpu); | |
1da177e4 LT |
518 | |
519 | for (i = 0; i < available; ++i) { | |
2d87b14c RR |
520 | sample = op_cpu_buffer_read_entry(&entry, cpu); |
521 | if (!sample) | |
6dad828b | 522 | break; |
73185e0a | 523 | |
2d87b14c | 524 | if (is_code(sample->eip)) { |
ae735e99 RR |
525 | flags = sample->event; |
526 | if (flags & TRACE_BEGIN) { | |
527 | state = sb_bt_start; | |
528 | add_trace_begin(); | |
529 | } | |
530 | if (flags & KERNEL_CTX_SWITCH) { | |
1da177e4 | 531 | /* kernel/userspace switch */ |
ae735e99 | 532 | in_kernel = flags & IS_KERNEL; |
1da177e4 LT |
533 | if (state == sb_buffer_start) |
534 | state = sb_sample_start; | |
ae735e99 RR |
535 | add_kernel_ctx_switch(flags & IS_KERNEL); |
536 | } | |
bd7dc46f RR |
537 | if (flags & USER_CTX_SWITCH |
538 | && op_cpu_buffer_get_data(&entry, &val)) { | |
1da177e4 | 539 | /* userspace context switch */ |
bd7dc46f | 540 | new = (struct task_struct *)val; |
fd7826d5 | 541 | oldmm = mm; |
1da177e4 LT |
542 | release_mm(oldmm); |
543 | mm = take_tasks_mm(new); | |
544 | if (mm != oldmm) | |
545 | cookie = get_exec_dcookie(mm); | |
546 | add_user_ctx_switch(new, cookie); | |
1da177e4 | 547 | } |
1acda878 RR |
548 | if (op_cpu_buffer_get_size(&entry)) |
549 | add_data(&entry, mm); | |
317f33bc RR |
550 | continue; |
551 | } | |
552 | ||
553 | if (state < sb_bt_start) | |
554 | /* ignore sample */ | |
555 | continue; | |
556 | ||
2d87b14c | 557 | if (add_sample(mm, sample, in_kernel)) |
317f33bc RR |
558 | continue; |
559 | ||
560 | /* ignore backtraces if failed to add a sample */ | |
561 | if (state == sb_bt_start) { | |
562 | state = sb_bt_ignore; | |
563 | atomic_inc(&oprofile_stats.bt_lost_no_mapping); | |
1da177e4 | 564 | } |
1da177e4 LT |
565 | } |
566 | release_mm(mm); | |
567 | ||
568 | mark_done(cpu); | |
569 | ||
59cc185a | 570 | mutex_unlock(&buffer_mutex); |
1da177e4 | 571 | } |
a5598ca0 CL |
572 | |
573 | /* The function can be used to add a buffer worth of data directly to | |
574 | * the kernel buffer. The buffer is assumed to be a circular buffer. | |
575 | * Take the entries from index start and end at index end, wrapping | |
576 | * at max_entries. | |
577 | */ | |
578 | void oprofile_put_buff(unsigned long *buf, unsigned int start, | |
579 | unsigned int stop, unsigned int max) | |
580 | { | |
581 | int i; | |
582 | ||
583 | i = start; | |
584 | ||
585 | mutex_lock(&buffer_mutex); | |
586 | while (i != stop) { | |
587 | add_event_entry(buf[i++]); | |
588 | ||
589 | if (i >= max) | |
590 | i = 0; | |
591 | } | |
592 | ||
593 | mutex_unlock(&buffer_mutex); | |
594 | } | |
595 |