KVM: ppc: Write only modified shadow entries into the TLB on exit

Track which TLB entries need to be written, instead of overwriting everything
below the high water mark. Typically only a single guest TLB entry will be
modified in a single exit.

Guest boot time performance improvement: about 15%.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index 594064953951..1631d670b9ed 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -357,6 +357,7 @@ int main(void)
         DEFINE(VCPU_HOST_STACK, offsetof(struct kvm_vcpu, arch.host_stack));
         DEFINE(VCPU_HOST_PID, offsetof(struct kvm_vcpu, arch.host_pid));
         DEFINE(VCPU_SHADOW_TLB, offsetof(struct kvm_vcpu, arch.shadow_tlb));
+        DEFINE(VCPU_SHADOW_MOD, offsetof(struct kvm_vcpu, arch.shadow_tlb_mod));
         DEFINE(VCPU_GPRS, offsetof(struct kvm_vcpu, arch.gpr));
         DEFINE(VCPU_LR, offsetof(struct kvm_vcpu, arch.lr));
         DEFINE(VCPU_CR, offsetof(struct kvm_vcpu, arch.cr));