diff options
Diffstat (limited to 'linuxthreads/sysdeps/pthread/timer_settime.c')
-rw-r--r-- | linuxthreads/sysdeps/pthread/timer_settime.c | 55 |
1 files changed, 38 insertions, 17 deletions
diff --git a/linuxthreads/sysdeps/pthread/timer_settime.c b/linuxthreads/sysdeps/pthread/timer_settime.c index 63b117f..858edc7 100644 --- a/linuxthreads/sysdeps/pthread/timer_settime.c +++ b/linuxthreads/sysdeps/pthread/timer_settime.c @@ -35,11 +35,9 @@ timer_settime (timerid, flags, value, ovalue) struct timer_node *timer; struct thread_node *thread = NULL; struct timespec now; - int have_now = 0; + int have_now = 0, need_wakeup = 0; int retval = -1; - pthread_mutex_lock (&__timer_mutex); - timer = timer_id2ptr (timerid); if (timer == NULL) { @@ -56,14 +54,40 @@ timer_settime (timerid, flags, value, ovalue) goto bail; } + /* Will need to know current time since this is a relative timer; + might as well make the system call outside of the lock now! */ + + if ((flags & TIMER_ABSTIME) == 0) + { + clock_gettime (timer->clock, &now); + have_now = 1; + } + + pthread_mutex_lock (&__timer_mutex); + + /* One final check of timer validity; this one is possible only + until we have the mutex, which guards the inuse flag. */ + + if (!timer->inuse) + { + errno = EINVAL; + goto unlock_bail; + } + if (ovalue != NULL) { ovalue->it_interval = timer->value.it_interval; if (timer->armed) { - clock_gettime (timer->clock, &now); - have_now = 1; + if (! have_now) + { + pthread_mutex_unlock (&__timer_mutex); + clock_gettime (timer->clock, &now); + have_now = 1; + pthread_mutex_lock (&__timer_mutex); + } + timespec_sub (&ovalue->it_value, &timer->expirytime, &now); } else @@ -75,11 +99,12 @@ timer_settime (timerid, flags, value, ovalue) timer->value = *value; - list_unlink (&timer->links); + list_unlink_ip (&timer->links); timer->armed = 0; thread = timer->thread; + /* A value of { 0, 0 } causes the timer to be stopped. */ if (value->it_value.tv_sec != 0 || __builtin_expect (value->it_value.tv_nsec != 0, 1)) { @@ -87,25 +112,21 @@ timer_settime (timerid, flags, value, ovalue) /* The user specified the expiration time. */ timer->expirytime = value->it_value; else - { - if (! have_now) - clock_gettime (timer->clock, &now); - - timespec_add (&timer->expirytime, &now, &value->it_value); - } + timespec_add (&timer->expirytime, &now, &value->it_value); - __timer_thread_queue_timer (thread, timer); + /* Only need to wake up the thread if timer is inserted + at the head of the queue. */ + need_wakeup = __timer_thread_queue_timer (thread, timer); timer->armed = 1; } retval = 0; -bail: +unlock_bail: pthread_mutex_unlock (&__timer_mutex); - /* TODO: optimize this. Only need to wake up the thread if inserting - a new timer at the head of the queue. */ - if (thread != NULL) +bail: + if (thread != NULL && need_wakeup) __timer_thread_wakeup (thread); return retval; |