lkml.org 
[lkml]   [2016]   [Jun]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] locking/osq: Drop the overload of osq lock
On Sun, Jun 26, 2016 at 12:59:01PM +0800, panxinhui wrote:
>
> > 在 2016年6月26日,03:12,Peter Zijlstra <peterz@infradead.org> 写道:
> >
> > On Sun, Jun 26, 2016 at 01:27:51AM +0800, panxinhui wrote:
> >
> >> by the way I still think mutex_unlock has a big overload too.
> >
> > Do you mean overhead?
> >
> oh, maybe you are right.

> mutex_unlock ’s implementation uses inc_return variant on ppc, and
> that’s expensive. I am thinking of using cmpxchg instead.

That statement doesn't make any sense. PPC is an LL/SC arch, inc_return
and cmpxchg are the 'same' LL/SC loop.

\
 
 \ /
  Last update: 2016-06-27 10:41    [W:0.068 / U:0.268 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site