lkml.org 
[lkml]   [2017]   [Aug]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC PATCH 12/12] housekeeping: Reimplement isolcpus on housekeeping
On Thu, Aug 31, 2017 at 08:53:56PM +0200, Thomas Gleixner wrote:
> On Mon, 28 Aug 2017, Frederic Weisbecker wrote:
> > On Mon, Aug 28, 2017 at 06:24:16PM +0200, Peter Zijlstra wrote:
> > > On Mon, Aug 28, 2017 at 05:27:15PM +0200, Frederic Weisbecker wrote:
> > > > Although for example I guess (IIUC) that if you create an unbound
> > > > timer on a NULL domain, it will be stuck on it for ever as we can't
> > > > walk any hierarchy from the current CPU domain.
> > >
> > > Not sure what you're on about. Timers have their own hierarchy.
> >
> > Check out get_nohz_timer_target() which relies on scheduler hierarchies to
> > look up a CPU to enqueue an unpinned timer on.
>
> Which is one of the most idiotic things we have in that code
> path. Anna-Maria has posted this series which gets rid of that nonsense, by
> queueing the timer on the current cpu into a wheel, which gets pulled in by
> others. That makes a lot of sense because most of these timers get canceled
> before expiry anyway. But we still need to fix the fallout and the few
> corner cases to make that work reliably. We'll do that hopefully sooner
> than later.

Sure, I definetly agree with that change.

\
 
 \ /
  Last update: 2017-09-01 01:00    [W:0.050 / U:0.272 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site