Re: [PATCH v2 0/2] x86/entry: speed up context-tracking system calls by 150 clock cycles

From: Paolo Bonzini
Date: Tue Jun 28 2016 - 08:16:21 EST




On 20/06/2016 16:58, Paolo Bonzini wrote:
> The first patches are the two optimizations I posted on May 30th
> for the system call entry/exit code. The only change is in the
> function names, which use the user_{enter,exit}_irqoff favored
> by Andy and Ingo. The first patch matches what commit d0e536d8939
> ("context_tracking: avoid irq_save/irq_restore on guest entry and exit",
> 2015-10-28) did for guest entry and exit. The second simply adds
> an inline annotation; the compiler doesn't figure it out because the
> function is not static.
>
> The second two patches move guest_{enter,exit} to the same naming
> convention, removing the KVM wrappers kvm_guest_{enter,exit} and
> __kvm_guest_{enter,exit} in the process. I would like these two to
> go through the KVM tree because I have other optimizations for 4.8
> on top of these patches.

I'm applying patches 3 and 4 to the KVM tree.

Paolo