mbox series

[0/4,v2] rq-qos memory barrier shenanigans

Message ID 20190715201120.72749-1-josef@toxicpanda.com (mailing list archive)
Headers show
Series rq-qos memory barrier shenanigans | expand

Message

Josef Bacik July 15, 2019, 8:11 p.m. UTC 
This is the patch series to address the hang we saw in production because of
missed wakeups, and the other issues that Oleg noticed while reviewing the code.

v1->v2:
- rename wq_has_multiple_sleepers to wq_has_single_sleeper
- fix the check for has_sleepers in the missed wake-ups patch
- fix the barrier issues around got_token that Oleg noticed
- dropped the has_sleepers reset that Oleg noticed we didn't need

Thanks,

Josef

Comments

Oleg Nesterov July 16, 2019, 8:39 a.m. UTC | #1 
On 07/15, Josef Bacik wrote:
>
> This is the patch series to address the hang we saw in production because of
> missed wakeups, and the other issues that Oleg noticed while reviewing the code.

You missed another problem. See
https://lore.kernel.org/linux-block/20190711114543.GA14901@redhat.com/

IOW, rq_qos_wait() needs set_current_state(TASK_UNINTERRUPTIBLE) after
io_schedule().

Oleg.