lkml.org 
[lkml]   [2021]   [Dec]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] sched: optimize __cond_resched_lock()
On Tue, Dec 21, 2021 at 11:09:00AM +0100, Peter Zijlstra wrote:
> On Tue, Dec 21, 2021 at 09:52:28AM +0100, Peter Zijlstra wrote:
> > On Tue, Dec 21, 2021 at 03:23:16PM +0800, xuhaifeng wrote:
> > > if the kernel is preemptible(CONFIG_PREEMPTION=y), schedule()may be
> > > called twice, once via spin_unlock, once via preempt_schedule_common.
> > >
> > > we can add one conditional, check TIF_NEED_RESCHED flag again,
> > > to avoid this.
> >
> > You can also make it more similar to __cond_resched() instead of making
> > it more different.
>
> Bah, sorry, had to wake up first :/
>
> cond_resched_lock still needs to exist for PREEMPT because locks won't
> magically release themselves.
>
> Still don't much like the patch though, how's this work for you?
>
> That's arguably the right thing to do work PREEMPT_DYNAMIC too.

Duh, those would need cond_resched() proper, clearly I should just give
up and call it a holiday already..

\
 
 \ /
  Last update: 2021-12-21 13:03    [W:0.048 / U:0.564 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site