arm64: KVM: Optimize arm64 skip 30-50% vfp/simd save/restore on exits
authorMario Smarduch <m.smarduch@samsung.com>
Thu, 16 Jul 2015 21:29:37 +0000 (22:29 +0100)
committerMarc Zyngier <marc.zyngier@arm.com>
Wed, 19 Aug 2015 21:25:19 +0000 (22:25 +0100)
commit33c76a0b8126946026fa1122cb774553afae0956
tree1ea5e6afabc2d383755984064899857928c71f43
parentf120cd6533d21075ab103ae6c225b1697853660d
arm64: KVM: Optimize arm64 skip 30-50% vfp/simd save/restore on exits

This patch only saves and restores FP/SIMD registers on Guest access. To do
this cptr_el2 FP/SIMD trap is set on Guest entry and later checked on exit.
lmbench, hackbench show significant improvements, for 30-50% exits FP/SIMD
context is not saved/restored

[chazy/maz: fixed save/restore logic for 32bit guests]

Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
arch/arm64/include/asm/kvm_arm.h
arch/arm64/kvm/hyp.S