Messages in this thread |  | | | Date | Mon, 10 Mar 2008 21:17:07 +0100 | | From | "H. Peter Anvin" <> | | Subject | Re: P6 NOPs again: MPSC? |
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Hugh Dickins wrote: > I've now noticed that the machine I call MPENTIUM4 for 32-bit kernels > is called MPSC for 64-bit kernels, and in that case it still doesn't > get the P6 NOPs which I'm guessing it ought to (yeah, I'm so excited > about the speedup I can expect from P6 NOPs, can we perhaps have a > little silvery "Using Genuine P6 NOPs" sticker to put on the box? ;) > > I'm suspecting that the patch below is actually wrong, and that it's > really the "(X86_64 || !X86_GENERIC) &&" which should be changed; > but very unsure of my ground and what's right for CPU_GENERIC - > the 32/64 heritage of x86/Kconfig.cpu rather confuses me. > > Over to you to do the right thing, I'm hoping, please, Peter! >
X86_64 && !X86_GENERIC comes from not wanting to be a compatibility issue when compiling for generic CPUs. There are some 32-bit otherwise i686-compatible chips (from VIA and Transmeta) which don't have these NOPs.
-hpa
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