diff options
Diffstat (limited to 'arch/x86/kvm/x86.c')
-rw-r--r-- | arch/x86/kvm/x86.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index bf80ce7..c42134e 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -7086,14 +7086,25 @@ void kvm_put_guest_fpu(struct kvm_vcpu *vcpu) { kvm_put_guest_xcr0(vcpu); - if (!vcpu->guest_fpu_loaded) + if (!vcpu->guest_fpu_loaded) { + vcpu->fpu_counter = 0; return; + } vcpu->guest_fpu_loaded = 0; fpu_save_init(&vcpu->arch.guest_fpu); __kernel_fpu_end(); ++vcpu->stat.fpu_reload; - kvm_make_request(KVM_REQ_DEACTIVATE_FPU, vcpu); + /* + * If using eager FPU mode, or if the guest is a frequent user + * of the FPU, just leave the FPU active for next time. + * Every 255 times fpu_counter rolls over to 0; a guest that uses + * the FPU in bursts will revert to loading it on demand. + */ + if (!use_eager_fpu()) { + if (++vcpu->fpu_counter < 5) + kvm_make_request(KVM_REQ_DEACTIVATE_FPU, vcpu); + } trace_kvm_fpu(0); } |