[2/3] powerpc/64s/idle: avoid sync for KVM state when waking from idle

[Michael Ellerman]

On Fri, 2017-11-17 at 14:08:06 UTC, Nicholas Piggin wrote:
> When waking from a CPU idle instruction (e.g., nap or stop), the sync
> for ordering the KVM secondary thread state can be avoided if there
> wakeup is coming from a kernel context rather than KVM context.
> 
> This improves performance for ping-pong benchmark with the stop0 idle
> state by 0.46% for 2 threads in the same core, and 1.02% for different
> cores.
> 
> Signed-off-by: Nicholas Piggin <npiggin at gmail.com>

Applied to powerpc next, thanks.

https://git.kernel.org/powerpc/c/8c1c7fb0b5ec95c392e9b585a6cf8c

cheers