Re: [PATCH v10 0/5] shut down devices asynchronously
From: David Jeffery
Date: Fri Jul 04 2025 - 10:10:09 EST
On Fri, Jul 4, 2025 at 9:45 AM Greg Kroah-Hartman
<gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
>
> On Fri, Jul 04, 2025 at 09:38:15AM -0400, David Jeffery wrote:
> > On Thu, Jul 3, 2025 at 7:47 AM Christoph Hellwig <hch@xxxxxx> wrote:
> > >
> > > On Wed, Jun 25, 2025 at 03:18:48PM -0500, Stuart Hayes wrote:
> > > > Address resource and timing issues when spawning a unique async thread
> > > > for every device during shutdown:
> > > > * Make the asynchronous threads able to shut down multiple devices,
> > > > instead of spawning a unique thread for every device.
> > > > * Modify core kernel async code with a custom wake function so it
> > > > doesn't wake up threads waiting to synchronize every time the cookie
> > > > changes
> > >
> > > Given all these thread spawning issues, why can't we just go back
> > > to the approach that kicks off shutdown asynchronously and then waits
> > > for it without spawning all these threads?
> > >
> >
> > The async subsystem fix is something that should be fixed regardless
> > of async shutdown. Async shutdown's use just exposed its thundering
> > herd behavior which is easily fixed.
>
> Great, then please submit that on its own and get the maintainer of that
> subsystem to agree and accept it as I have no way to judge that code at
> all.
Unfortunately, it does not have a maintainer listed and sees limited
activity. Would CC-ing some of the recent developers of kernel/async.c
to ask them to review be recommended in this situation?
David Jeffery