Re: [PATCH] remoteproc: Create a separate workqueue for recovery tasks

[Alex Elder]

On 12/17/20 12:21 PM, rishabhb@xxxxxxxxxxxxxx wrote:
> On 2020-12-17 08:12, Alex Elder wrote:
> > On 12/15/20 4:55 PM, Bjorn Andersson wrote:
> > > On Sat 12 Dec 14:48 CST 2020, Rishabh Bhatnagar wrote:
> > >
> > > > Create an unbound high priority workqueue for recovery tasks.
> >
> > I have been looking at a different issue that is caused by
> > crash notification.
> >
> > What happened was that the modem crashed while the AP was
> > in system suspend (or possibly even resuming) state.  And
> > there is no guarantee that the system will have called a
> > driver's ->resume callback when the crash notification is
> > delivered.
> >
> > In my case (in the IPA driver), handling a modem crash
> > cannot be done while the driver is suspended; i.e. the
> > activities in its ->resume callback must be completed
> > before we can recover from the crash.
> >
> > For this reason I might like to change the way the
> > crash notification is handled, but what I'd rather see
> > is to have the work queue not run until user space
> > is unfrozen, which would guarantee that all drivers
> > that have registered for a crash notification will
> > be resumed when the notification arrives.
> >
> > I'm not sure how that interacts with what you are
> > looking for here.  I think the workqueue could still
> > be unbound, but its work would be delayed longer before
> > any notification (and recovery) started.
> >
> >                     -Alex
> In that case, maybe adding a "WQ_FREEZABLE" flag might help?

Yes, exactly.  But how does that affect whatever you were
trying to do with your patch?

					-Alex

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