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-rw-r--r--kernel/posix-timers.c153
1 files changed, 61 insertions, 92 deletions
diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
index 5131e5471169..b931d7cedbfa 100644
--- a/kernel/posix-timers.c
+++ b/kernel/posix-timers.c
@@ -223,6 +223,15 @@ static int posix_ktime_get_ts(clockid_t which_clock, struct timespec *tp)
223} 223}
224 224
225/* 225/*
226 * Get monotonic time for posix timers
227 */
228static int posix_get_monotonic_raw(clockid_t which_clock, struct timespec *tp)
229{
230 getrawmonotonic(tp);
231 return 0;
232}
233
234/*
226 * Initialize everything, well, just everything in Posix clocks/timers ;) 235 * Initialize everything, well, just everything in Posix clocks/timers ;)
227 */ 236 */
228static __init int init_posix_timers(void) 237static __init int init_posix_timers(void)
@@ -235,9 +244,15 @@ static __init int init_posix_timers(void)
235 .clock_get = posix_ktime_get_ts, 244 .clock_get = posix_ktime_get_ts,
236 .clock_set = do_posix_clock_nosettime, 245 .clock_set = do_posix_clock_nosettime,
237 }; 246 };
247 struct k_clock clock_monotonic_raw = {
248 .clock_getres = hrtimer_get_res,
249 .clock_get = posix_get_monotonic_raw,
250 .clock_set = do_posix_clock_nosettime,
251 };
238 252
239 register_posix_clock(CLOCK_REALTIME, &clock_realtime); 253 register_posix_clock(CLOCK_REALTIME, &clock_realtime);
240 register_posix_clock(CLOCK_MONOTONIC, &clock_monotonic); 254 register_posix_clock(CLOCK_MONOTONIC, &clock_monotonic);
255 register_posix_clock(CLOCK_MONOTONIC_RAW, &clock_monotonic_raw);
241 256
242 posix_timers_cache = kmem_cache_create("posix_timers_cache", 257 posix_timers_cache = kmem_cache_create("posix_timers_cache",
243 sizeof (struct k_itimer), 0, SLAB_PANIC, 258 sizeof (struct k_itimer), 0, SLAB_PANIC,
@@ -298,6 +313,7 @@ void do_schedule_next_timer(struct siginfo *info)
298 313
299int posix_timer_event(struct k_itimer *timr, int si_private) 314int posix_timer_event(struct k_itimer *timr, int si_private)
300{ 315{
316 int shared, ret;
301 /* 317 /*
302 * FIXME: if ->sigq is queued we can race with 318 * FIXME: if ->sigq is queued we can race with
303 * dequeue_signal()->do_schedule_next_timer(). 319 * dequeue_signal()->do_schedule_next_timer().
@@ -311,25 +327,10 @@ int posix_timer_event(struct k_itimer *timr, int si_private)
311 */ 327 */
312 timr->sigq->info.si_sys_private = si_private; 328 timr->sigq->info.si_sys_private = si_private;
313 329
314 timr->sigq->info.si_signo = timr->it_sigev_signo; 330 shared = !(timr->it_sigev_notify & SIGEV_THREAD_ID);
315 timr->sigq->info.si_code = SI_TIMER; 331 ret = send_sigqueue(timr->sigq, timr->it_process, shared);
316 timr->sigq->info.si_tid = timr->it_id; 332 /* If we failed to send the signal the timer stops. */
317 timr->sigq->info.si_value = timr->it_sigev_value; 333 return ret > 0;
318
319 if (timr->it_sigev_notify & SIGEV_THREAD_ID) {
320 struct task_struct *leader;
321 int ret = send_sigqueue(timr->sigq, timr->it_process, 0);
322
323 if (likely(ret >= 0))
324 return ret;
325
326 timr->it_sigev_notify = SIGEV_SIGNAL;
327 leader = timr->it_process->group_leader;
328 put_task_struct(timr->it_process);
329 timr->it_process = leader;
330 }
331
332 return send_sigqueue(timr->sigq, timr->it_process, 1);
333} 334}
334EXPORT_SYMBOL_GPL(posix_timer_event); 335EXPORT_SYMBOL_GPL(posix_timer_event);
335 336
@@ -468,11 +469,9 @@ sys_timer_create(const clockid_t which_clock,
468 struct sigevent __user *timer_event_spec, 469 struct sigevent __user *timer_event_spec,
469 timer_t __user * created_timer_id) 470 timer_t __user * created_timer_id)
470{ 471{
471 int error = 0; 472 struct k_itimer *new_timer;
472 struct k_itimer *new_timer = NULL; 473 int error, new_timer_id;
473 int new_timer_id; 474 struct task_struct *process;
474 struct task_struct *process = NULL;
475 unsigned long flags;
476 sigevent_t event; 475 sigevent_t event;
477 int it_id_set = IT_ID_NOT_SET; 476 int it_id_set = IT_ID_NOT_SET;
478 477
@@ -490,12 +489,11 @@ sys_timer_create(const clockid_t which_clock,
490 goto out; 489 goto out;
491 } 490 }
492 spin_lock_irq(&idr_lock); 491 spin_lock_irq(&idr_lock);
493 error = idr_get_new(&posix_timers_id, (void *) new_timer, 492 error = idr_get_new(&posix_timers_id, new_timer, &new_timer_id);
494 &new_timer_id);
495 spin_unlock_irq(&idr_lock); 493 spin_unlock_irq(&idr_lock);
496 if (error == -EAGAIN) 494 if (error) {
497 goto retry; 495 if (error == -EAGAIN)
498 else if (error) { 496 goto retry;
499 /* 497 /*
500 * Weird looking, but we return EAGAIN if the IDR is 498 * Weird looking, but we return EAGAIN if the IDR is
501 * full (proper POSIX return value for this) 499 * full (proper POSIX return value for this)
@@ -526,67 +524,43 @@ sys_timer_create(const clockid_t which_clock,
526 error = -EFAULT; 524 error = -EFAULT;
527 goto out; 525 goto out;
528 } 526 }
529 new_timer->it_sigev_notify = event.sigev_notify; 527 rcu_read_lock();
530 new_timer->it_sigev_signo = event.sigev_signo; 528 process = good_sigevent(&event);
531 new_timer->it_sigev_value = event.sigev_value; 529 if (process)
532 530 get_task_struct(process);
533 read_lock(&tasklist_lock); 531 rcu_read_unlock();
534 if ((process = good_sigevent(&event))) {
535 /*
536 * We may be setting up this process for another
537 * thread. It may be exiting. To catch this
538 * case the we check the PF_EXITING flag. If
539 * the flag is not set, the siglock will catch
540 * him before it is too late (in exit_itimers).
541 *
542 * The exec case is a bit more invloved but easy
543 * to code. If the process is in our thread
544 * group (and it must be or we would not allow
545 * it here) and is doing an exec, it will cause
546 * us to be killed. In this case it will wait
547 * for us to die which means we can finish this
548 * linkage with our last gasp. I.e. no code :)
549 */
550 spin_lock_irqsave(&process->sighand->siglock, flags);
551 if (!(process->flags & PF_EXITING)) {
552 new_timer->it_process = process;
553 list_add(&new_timer->list,
554 &process->signal->posix_timers);
555 if (new_timer->it_sigev_notify == (SIGEV_SIGNAL|SIGEV_THREAD_ID))
556 get_task_struct(process);
557 spin_unlock_irqrestore(&process->sighand->siglock, flags);
558 } else {
559 spin_unlock_irqrestore(&process->sighand->siglock, flags);
560 process = NULL;
561 }
562 }
563 read_unlock(&tasklist_lock);
564 if (!process) { 532 if (!process) {
565 error = -EINVAL; 533 error = -EINVAL;
566 goto out; 534 goto out;
567 } 535 }
568 } else { 536 } else {
569 new_timer->it_sigev_notify = SIGEV_SIGNAL; 537 event.sigev_notify = SIGEV_SIGNAL;
570 new_timer->it_sigev_signo = SIGALRM; 538 event.sigev_signo = SIGALRM;
571 new_timer->it_sigev_value.sival_int = new_timer->it_id; 539 event.sigev_value.sival_int = new_timer->it_id;
572 process = current->group_leader; 540 process = current->group_leader;
573 spin_lock_irqsave(&process->sighand->siglock, flags); 541 get_task_struct(process);
574 new_timer->it_process = process;
575 list_add(&new_timer->list, &process->signal->posix_timers);
576 spin_unlock_irqrestore(&process->sighand->siglock, flags);
577 } 542 }
578 543
544 new_timer->it_sigev_notify = event.sigev_notify;
545 new_timer->sigq->info.si_signo = event.sigev_signo;
546 new_timer->sigq->info.si_value = event.sigev_value;
547 new_timer->sigq->info.si_tid = new_timer->it_id;
548 new_timer->sigq->info.si_code = SI_TIMER;
549
550 spin_lock_irq(&current->sighand->siglock);
551 new_timer->it_process = process;
552 list_add(&new_timer->list, &current->signal->posix_timers);
553 spin_unlock_irq(&current->sighand->siglock);
554
555 return 0;
579 /* 556 /*
580 * In the case of the timer belonging to another task, after 557 * In the case of the timer belonging to another task, after
581 * the task is unlocked, the timer is owned by the other task 558 * the task is unlocked, the timer is owned by the other task
582 * and may cease to exist at any time. Don't use or modify 559 * and may cease to exist at any time. Don't use or modify
583 * new_timer after the unlock call. 560 * new_timer after the unlock call.
584 */ 561 */
585
586out: 562out:
587 if (error) 563 release_posix_timer(new_timer, it_id_set);
588 release_posix_timer(new_timer, it_id_set);
589
590 return error; 564 return error;
591} 565}
592 566
@@ -597,7 +571,7 @@ out:
597 * the find to the timer lock. To avoid a dead lock, the timer id MUST 571 * the find to the timer lock. To avoid a dead lock, the timer id MUST
598 * be release with out holding the timer lock. 572 * be release with out holding the timer lock.
599 */ 573 */
600static struct k_itimer * lock_timer(timer_t timer_id, unsigned long *flags) 574static struct k_itimer *lock_timer(timer_t timer_id, unsigned long *flags)
601{ 575{
602 struct k_itimer *timr; 576 struct k_itimer *timr;
603 /* 577 /*
@@ -605,23 +579,20 @@ static struct k_itimer * lock_timer(timer_t timer_id, unsigned long *flags)
605 * flags part over to the timer lock. Must not let interrupts in 579 * flags part over to the timer lock. Must not let interrupts in
606 * while we are moving the lock. 580 * while we are moving the lock.
607 */ 581 */
608
609 spin_lock_irqsave(&idr_lock, *flags); 582 spin_lock_irqsave(&idr_lock, *flags);
610 timr = (struct k_itimer *) idr_find(&posix_timers_id, (int) timer_id); 583 timr = idr_find(&posix_timers_id, (int)timer_id);
611 if (timr) { 584 if (timr) {
612 spin_lock(&timr->it_lock); 585 spin_lock(&timr->it_lock);
613 586 if (timr->it_process &&
614 if ((timr->it_id != timer_id) || !(timr->it_process) || 587 same_thread_group(timr->it_process, current)) {
615 !same_thread_group(timr->it_process, current)) {
616 spin_unlock(&timr->it_lock);
617 spin_unlock_irqrestore(&idr_lock, *flags);
618 timr = NULL;
619 } else
620 spin_unlock(&idr_lock); 588 spin_unlock(&idr_lock);
621 } else 589 return timr;
622 spin_unlock_irqrestore(&idr_lock, *flags); 590 }
591 spin_unlock(&timr->it_lock);
592 }
593 spin_unlock_irqrestore(&idr_lock, *flags);
623 594
624 return timr; 595 return NULL;
625} 596}
626 597
627/* 598/*
@@ -862,8 +833,7 @@ retry_delete:
862 * This keeps any tasks waiting on the spin lock from thinking 833 * This keeps any tasks waiting on the spin lock from thinking
863 * they got something (see the lock code above). 834 * they got something (see the lock code above).
864 */ 835 */
865 if (timer->it_sigev_notify == (SIGEV_SIGNAL|SIGEV_THREAD_ID)) 836 put_task_struct(timer->it_process);
866 put_task_struct(timer->it_process);
867 timer->it_process = NULL; 837 timer->it_process = NULL;
868 838
869 unlock_timer(timer, flags); 839 unlock_timer(timer, flags);
@@ -890,8 +860,7 @@ retry_delete:
890 * This keeps any tasks waiting on the spin lock from thinking 860 * This keeps any tasks waiting on the spin lock from thinking
891 * they got something (see the lock code above). 861 * they got something (see the lock code above).
892 */ 862 */
893 if (timer->it_sigev_notify == (SIGEV_SIGNAL|SIGEV_THREAD_ID)) 863 put_task_struct(timer->it_process);
894 put_task_struct(timer->it_process);
895 timer->it_process = NULL; 864 timer->it_process = NULL;
896 865
897 unlock_timer(timer, flags); 866 unlock_timer(timer, flags);