lkml.org 
[lkml]   [2010]   [Nov]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] atomic: add atomic_inc_not_zero_hint()
> > atomic_read() and atomic_cmpxchg(). We tried prefetchw() and it was a
> > performance drop. It was with only 16 cpus contending on neighbour
>
> Does prefetchw work? Andi claims that prefetchw is not working on
> x86 and I doubt that you ran tests on Itanium.

AMD supports it due to their MOESI protocol, but it's not supported
in MESIF as used by Intel QPI. The kernel maps it on Intel to
ordinary prefetch.

-Andi

--
ak@linux.intel.com -- Speaking for myself only.


\
 
 \ /
  Last update: 2010-11-15 15:41    [W:0.055 / U:0.100 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site