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    SubjectRe: page fault scalability patch V8: [4/7] universally available cmpxchg on i386
    On Tue, Sep 21, 2004 at 06:41:25PM +0300, Denis Vlasenko wrote:
    > On Monday 20 September 2004 23:57, Andi Kleen wrote:
    > > On Mon, Sep 20, 2004 at 01:49:20PM -0700, Christoph Lameter wrote:
    > > > On Mon, 20 Sep 2004, Denis Vlasenko wrote:
    > > >
    > > > > I think it shouldn't be this way.
    > > > >
    > > > > OTOH for !CONFIG_386 case it makes perfect sense to have it inlined.
    > > >
    > > > Would the following revised patch be acceptable?
    > >
    > > You would need an EXPORT_SYMBOL at least. But to be honest your
    > > original patch was much simpler and nicer and cmpxchg is not called
    > > that often that it really matters. I would just ignore Denis'
    > > suggestion and stay with the old patch.
    >
    > A bit faster approach (for CONFIG_386 case) would be using

    It's actually slower. Many x86 CPUs cannot predict indirect jumps
    and those that do cannot predict them as well as a test and jump.

    -Andi
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