maria-developers team mailing list archive

[Sergei Golubchik <serg@xxxxxxxxxxx>]

Hi, Sergey!

On Feb 02, svoj@xxxxxxxxxxx wrote:
> revision-id: 7320cbf85ddfaf7ef76c8f03718819377fd14318
> parent(s): 11deb416fe12ebfd65a1f089c7eb6087c192e2dd
> committer: Sergey Vojtovich
> branch nick: 10.1
> timestamp: 2015-02-02 15:41:49 +0400
> message:
> 
> MDEV-7177 - Server hangs on shutdown after InnoDB error (main.plugin_loaderr
>             fails in buildbot)
> 
> There was a race condition in timer functionality of query timeouts.
> 
> Race was as following:
> main thread:          init_thr_timers()
> timer handler thread: my_thread_init()
> main thread:          end_thr_timer()/timer_thread_state= ABORTING
> timer handler thread: timer_thread_state= RUNNING, continue normal op
> main thread:          waits indefinitely for timer handler thread to go down
> 
> The original idea of the fix is to set RUNNING state in main thread, before
> starting timer handler thread. But it didn't survive further cleanups:
> - removed "timer_thread_state" and used "thr_timer_inited" for this purpose
> - removed unused "timer_thread_running"
> - removed code responisble for "timer handler thread" shutdown synchronization,
>   use pthread_join() instead.

That looks ok to me.

The only concern is - in end_thr_timer(), the old code had a timeout
waiting for a timer thread to die. pthread_join() doesn't.

I don't know if that's a problem, perhaps not.

Regards,
Sergei