lkml.org 
[lkml]   [2012]   [Feb]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] Extend mwait idle to optimize away CAL and RES interrupts to an idle CPU -v1
On Sat, Feb 25, 2012 at 05:32:53PM -0800, Paul E. McKenney wrote:
> On Fri, Feb 24, 2012 at 01:41:50PM +0800, Yong Zhang wrote:
> > On Thu, Feb 23, 2012 at 11:34:11AM -0800, Venki Pallipadi wrote:
> > > On Thu, Feb 23, 2012 at 1:30 AM, Peter Zijlstra <peterz@infradead.org> wrote:
> > > > Why not scheduler_ipi()?
> > >
> > > Was trying to avoid irq_enter/exit. As the work here is done in idle
> > > thread context, I though we could avoid enter/exit.
> >
> > It seems we could not.
> > At least RCU need it, see commit c5d753a55, otherwise we will get
> > warning like 'RCU used illegally from extended quiescent state!'
>
> If the use is tracing, then Steven Rostedt's patchset plus use of his
> _rcuidle() tracing variants handles this:
>
> https://lkml.org/lkml/2012/2/7/231
>
> If this is instead algorithmic use of RCU, a set of patches I have queued
> up for 3.4 will be required.

scheduler_ipi() doing more than tracing. Will look at your patches :)

Thanks,
Yong


\
 
 \ /
  Last update: 2012-02-27 10:09    [W:0.067 / U:14.852 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site