Messages in this thread | | | Date | Wed, 25 Apr 2018 15:05:22 +0200 | From | Oleg Nesterov <> | Subject | Re: [PATCH 2/3] drm/scheduler: Don't call wait_event_killable for signaled process. |
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On 04/24, Andrey Grodzovsky wrote: > > --- a/drivers/gpu/drm/scheduler/gpu_scheduler.c > +++ b/drivers/gpu/drm/scheduler/gpu_scheduler.c > @@ -227,9 +227,10 @@ void drm_sched_entity_do_release(struct drm_gpu_scheduler *sched, > return; > /** > * The client will not queue more IBs during this fini, consume existing > - * queued IBs or discard them on SIGKILL > + * queued IBs or discard them when in death signal state since > + * wait_event_killable can't receive signals in that state. > */ > - if ((current->flags & PF_SIGNALED) && current->exit_code == SIGKILL) > + if (current->flags & PF_SIGNALED)
please do not use PF_SIGNALED, it must die. Besides you can't rely on this flag in multi-threaded case. current->exit_code doesn't look right too.
> entity->fini_status = -ERESTARTSYS; > else > entity->fini_status = wait_event_killable(sched->job_scheduled,
So afaics the problem is that fatal_signal_pending() is not necessarily true after SIGKILL was already dequeued and thus wait_event_killable(), right?
This was already discussed, but it is not clear what we can/should do. We can probably change get_signal() to not dequeue SIGKILL or do something else to keep fatal_signal_pending() == T for the exiting killed thread.
But in this case we probably also want to discriminate the "real" SIGKILL's from group_exit/exec/coredump.
Oleg.
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