Re: [tip:x86/asm] x86: Speed up ___preempt_schedule*() by using THUNK helpers

[Linus Torvalds]

On Fri, Oct 3, 2014 at 2:56 PM, Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote:
>
> Is this thing missing a flags or cc clobber:
>
> # define __preempt_schedule() asm ("call ___preempt_schedule")

Yes, it should probably have a cc clobber. Although I think thet gcc
actually assumes all asms clobber flags on x86, so it shouldn't
matter.

> Is this all just to make the call sequence for preempt_schedule shorter?

Not so much the call sequence, but the code around the call - not
havign to spill live registers etc. But yes.

              Linus
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