Currently we save/restore fp/simd on each exit. The first patch optimizes arm64 save/restore, we only do so on Guest access. hackbench and several lmbench tests show anywhere from 30% to 50% of exits don't context switch the vfp/simd registers. For second patch 32-bit handler is updated to keep exit handling consistent with 64-bit code. Changes since v3: - Per Christoffers comment - changed comment for skip fp/simd in patch 1/2 - Changed cover text, clarify optimization in the context of this patch Changes since v2: - Only for patch 2/2 - Removed load_vcpu in switch_to_guest_vfp per Marcs comment - Got another chance to replace an unreferenced label with a comment Changes since v1: - only for patch 2/2 - Reworked trapping to vfp access handler Changes since inital version: - Addressed Marcs comments - Verified optimization improvements with lmbench and hackbench, updated commit message Mario Smarduch (2): Optimize arm64 skip 30-50% vfp/simd save/restore on exits keep arm vfp/simd exit handling consistent with arm64 arch/arm/kvm/interrupts.S | 14 +++++++------ arch/arm64/include/asm/kvm_arm.h | 5 ++++- arch/arm64/kvm/hyp.S | 45 +++++++++++++++++++++++++++++++++++++--- 3 files changed, 54 insertions(+), 10 deletions(-) -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
