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SubjectRe: [PATCH] x86: clean up
Roland McGrath wrote:
> You mean this one:
> /*
> * Align the actual code well away from the non-instruction data.
> * This is the best thing for the I-cache.
> */
> . = ALIGN(0x100);
> Reading the comment might make it obvious that it's intended for optimal
> code alignment. I suspect someone at the time told me 256 is as big as an
> I-cache line was ever likely to get. You could use L1_CACHE_BYTES instead
> I suppose.

Most likely 256 was chosen as a compromise between the the
then-documented value for coherency avoidance (128), future-proofing,
and waste.

I don't think we want to use different values on different platforms,
and end up with dramatically different vdsos when they still need to fit
in the same size envelope.


H. Peter Anvin, Intel Open Source Technology Center
I work for Intel. I don't speak on their behalf.

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