Canceling the timer thread runs under lock. The thread uses the same
lock to guard its timer_tracker struct access. If the timing is bad,
timer_settime or timer_delete grab the lock at the same time, the timer
expires. In the end, cancel waits for the thread sync while the thread
waits for ther lock to be released.
Fix this by not waiting for the thread sync under lock.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
On setting the timer, the thread is accidentally only canceled when
disarming the timer. This leaks one thread per timer_settimer call.
Move the thread cancellation where it belongs.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
The "optimized" condition to recognize an unarmed timer was plain
wrong. Replace it by checking the stored it_value against 0.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Combine with a bit of cleanup:
- Drop overrun_event_running in favor of overrun_count being -1.
- Fix include guard in posix_timer.h.
- Drop ununsed function timespec_to_us.
- Don't use Interlocked functions without need.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Allocating on the cygheap would copy information of the tracker into
the child process. A forked child knows the timer id and could simply
still access the (free'd but still valid) timer_tracker on the heap,
which is dangerous and very certainly doesn't reflect POSIX semantics.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
- Rename files timer.* to posix_timer.*.
- Reimplement using an OS timer rather than a handcrafted wait loop.
- Use a Slim R/W Lock for synchronization.
- Drop timer chaining. It doesn't server a purpose since all timers
are local only.
- Rename ttstart to itimer_tracker to better reflect its purpose.
It's not the anchor for a timer chain anymore anyway.
- Drop fixup_timers_after_fork. Everything is process-local, nothing
gets inherited.
- Rename timer_tracker::disarm_event to disarm_overrun_event for
better readability.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Corinna Vinschen