Messages in this thread | | | Date | Tue, 21 Sep 2004 17:45:42 +0200 | From | Andi Kleen <> | Subject | Re: page fault scalability patch V8: [4/7] universally available cmpxchg on i386 |
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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.
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