Re: [PATCH 0/3] Reduce length of the eagerfpu path during x86 context switches

[Mel Gorman]

On Wed, Aug 06, 2014 at 01:55:45PM +0100, Mel Gorman wrote:
> Eager FPU switching is used on CPUs that support xsave on the grounds
> that CPUs that support it can optimise the switch with xsaveopt and xrstor
> instead of serialising by updating cr0.TS which has serialising semantics.
> 
> The path for eagerfpu is fatter than it needs to be because it still
> maintains the fpu_counter for lazy FPU switches even though the information
> is never used. This patch splits the paths optimises the eagerfpu path a
> little. The benefit is marginal, it was just noticed when looking at why
> integer-only workloads were spending time saving/restoring FPU states.
> 

This was initially sent when it would collide with the merge window
which was stupid timing. Nothing has actually changed since but I wonder
if anyone had a chance to take a look at this patches?

Thanks

-- 
Mel Gorman
SUSE Labs
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