lkml.org 
[lkml]   [2009]   [Jul]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH -tip] x86: atomic64: inline atomic64_read()

    * Arjan van de Ven <arjan@infradead.org> wrote:

    > On Fri, 3 Jul 2009 20:04:50 +0200
    > Ingo Molnar <mingo@elte.hu> wrote:
    >
    > > > +static inline u64 atomic64_read(atomic64_t *ptr)
    > > > +{
    > > > + u64 res;
    > > > +
    > > > + asm volatile(
    > > > + "mov %%ebx, %%eax\n\t"
    > > > + "mov %%ecx, %%edx\n\t"
    > > > + LOCK_PREFIX "cmpxchg8b %1\n"
    >
    > also afaik cmpxchg implies the lock prefix, so no need to make an
    > explicit one... it just adds code size and alternatives-work

    good point!

    Is the same true of XADD as well? If yes then we can remove the lock
    prefix from those as well - there's a few uses of that on 32-bit and
    64-bit as well.

    Ingo


    \
     
     \ /
      Last update: 2009-07-03 20:21    [W:0.047 / U:118.956 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site