lkml.org 
[lkml]   [2009]   [Jun]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 1/2] lib: Provide generic atomic64_t implementation
Roland Dreier writes:

> FWIW, Nehalem EX actually goes to 8 cores/16 threads per socket. But
> worrying about 32-bit performance on Nehalem is a little silly -- this
> simplest solution is simply to run a 64-bit kernel.

I'm not worried about ANY x86 processor, 32-bit or 64-bit, in fact,
since x86 already has an atomic64_t implementation for both 32-bit and
64-bit.

It is interesting, though, that arch/x86/include/asm/atomic_32.h
unconditionally uses cmpxchg8b to implement atomic64_t, but I thought
that cmpxchg8b didn't exist in processors prior to the Pentium.
Presumably you can't use perf_counters on a 386 or 486.

Paul.


\
 
 \ /
  Last update: 2009-06-15 06:33    [W:0.061 / U:0.124 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site