lkml.org 
[lkml]   [2010]   [Feb]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [patch 2/3] scheduler: add full memory barriers upon task switch at runqueue lock/unlock
From
Date
On Mon, 2010-02-01 at 11:24 -0500, Steven Rostedt wrote:
>
> Doesn't set_bit imply a wmb()? If so couldn't we do:

Nope, that's what we have smp_mb__{before,after}_set_bit() for.

On x86 its a LOCK'ed op, so sure it implies a full membarrier, but not
in generic.

on x86 we have plenty serializing instructions before and after rq->curr
is set so none of the crazyness is needed at all. The only thing is !
x86.





\
 
 \ /
  Last update: 2010-02-01 17:33    [W:0.075 / U:0.756 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site