arm64: KVM: Optimize arm64 skip 30-50% vfp/simd save/restore on exits

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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>

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Mario Smarduch 2015-07-16 22:29:37 +01:00 • committed by Marc Zyngier

parent f120cd6533

commit 33c76a0b81

2 changed files with 68 additions and 10 deletions

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5

arch/arm64/include/asm/kvm_arm.h

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73

arch/arm64/kvm/hyp.S

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