* Peter Zijlstra <[email protected]> wrote:
> These patches optimize preempt_enable by firstly folding the preempt and
> need_resched tests into one -- this should work for all architectures. And
> secondly by providing per-arch preempt_count implementations; with x86 using
> per-cpu preempt_count for fastest access.
>
> These patches have been boot tested on CONFIG_PREEMPT=y x86_64 and survive
> building a x86_64-defconfig kernel.
>
> text data bss filename
> 11387014 1454776 1187840 defconfig-build/vmlinux.before
> 11352294 1454776 1187840 defconfig-build/vmlinux.after
That's a 0.3% size improvement (and most of the improvement is in
hotpaths), despite GCC is being somewhat stupid about not allowing us to
mark asm goto targets as cold paths and thus causes some unnecessary
register shuffling in some cases, right?
Not bad IMO.
Thanks,
Ingo
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