• H. Peter Anvin's avatar
    x86, asm: Clean up and simplify set_64bit() · 69309a05
    H. Peter Anvin authored
    Clean up and simplify set_64bit().  This code is quite old (1.3.11)
    and contains a fair bit of auxilliary machinery that current versions
    of gcc handle just fine automatically.  Worse, the auxilliary
    machinery can actually cause an unnecessary spill to memory.
    
    Furthermore, the loading of the old value inside the loop in the
    32-bit case is unnecessary: if the value doesn't match, the CMPXCHG8B
    instruction will already have loaded the "new previous" value for us.
    
    Clean up the comment, too, and remove page references to obsolete
    versions of the Intel SDM.
    Signed-off-by: default avatarH. Peter Anvin <hpa@zytor.com>
    LKML-Reference: <tip-*@vger.kernel.org>
    69309a05
cmpxchg_32.h 7.58 KB