KVM: PPC: Preload FPU when possible
There are some situations when we're pretty sure the guest will use the
FPU soon. So we can save the churn of going into the guest, finding out
it does want to use the FPU and going out again.
This patch adds preloading of the FPU when it's reasonable.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index b18415f..55c38e5 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -138,6 +138,10 @@
kvmppc_mmu_flush_segments(vcpu);
kvmppc_mmu_map_segment(vcpu, vcpu->arch.pc);
}
+
+ /* Preload FPU if it's enabled */
+ if (vcpu->arch.msr & MSR_FP)
+ kvmppc_handle_ext(vcpu, BOOK3S_INTERRUPT_FP_UNAVAIL, MSR_FP);
}
void kvmppc_inject_interrupt(struct kvm_vcpu *vcpu, int vec, u64 flags)
@@ -1196,6 +1200,10 @@
/* XXX we get called with irq disabled - change that! */
local_irq_enable();
+ /* Preload FPU if it's enabled */
+ if (vcpu->arch.msr & MSR_FP)
+ kvmppc_handle_ext(vcpu, BOOK3S_INTERRUPT_FP_UNAVAIL, MSR_FP);
+
ret = __kvmppc_vcpu_entry(kvm_run, vcpu);
local_irq_disable();