diff options
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/posix-cpu-timers.c | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c index e5d7bfdfa7d4..2313a4cc14ea 100644 --- a/kernel/posix-cpu-timers.c +++ b/kernel/posix-cpu-timers.c | |||
@@ -261,6 +261,40 @@ out: | |||
261 | rcu_read_unlock(); | 261 | rcu_read_unlock(); |
262 | } | 262 | } |
263 | 263 | ||
264 | static void update_gt_cputime(struct task_cputime *a, struct task_cputime *b) | ||
265 | { | ||
266 | if (cputime_gt(b->utime, a->utime)) | ||
267 | a->utime = b->utime; | ||
268 | |||
269 | if (cputime_gt(b->stime, a->stime)) | ||
270 | a->stime = b->stime; | ||
271 | |||
272 | if (b->sum_exec_runtime > a->sum_exec_runtime) | ||
273 | a->sum_exec_runtime = b->sum_exec_runtime; | ||
274 | } | ||
275 | |||
276 | void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times) | ||
277 | { | ||
278 | struct thread_group_cputimer *cputimer = &tsk->signal->cputimer; | ||
279 | struct task_cputime sum; | ||
280 | unsigned long flags; | ||
281 | |||
282 | spin_lock_irqsave(&cputimer->lock, flags); | ||
283 | if (!cputimer->running) { | ||
284 | cputimer->running = 1; | ||
285 | /* | ||
286 | * The POSIX timer interface allows for absolute time expiry | ||
287 | * values through the TIMER_ABSTIME flag, therefore we have | ||
288 | * to synchronize the timer to the clock every time we start | ||
289 | * it. | ||
290 | */ | ||
291 | thread_group_cputime(tsk, &sum); | ||
292 | update_gt_cputime(&cputimer->cputime, &sum); | ||
293 | } | ||
294 | *times = cputimer->cputime; | ||
295 | spin_unlock_irqrestore(&cputimer->lock, flags); | ||
296 | } | ||
297 | |||
264 | /* | 298 | /* |
265 | * Sample a process (thread group) clock for the given group_leader task. | 299 | * Sample a process (thread group) clock for the given group_leader task. |
266 | * Must be called with tasklist_lock held for reading. | 300 | * Must be called with tasklist_lock held for reading. |