From 78958563d8023db0c6d03a2fe2a64d79b47b4349 Mon Sep 17 00:00:00 2001 From: Aaron Lewis Date: Mon, 21 Oct 2019 16:30:22 -0700 Subject: [PATCH] KVM: x86: Remove unneeded kvm_vcpu variable, guest_xcr0_loaded The kvm_vcpu variable, guest_xcr0_loaded, is a waste of an 'int' and a conditional branch. VMX and SVM are the only users, and both unconditionally pair kvm_load_guest_xcr0() with kvm_put_guest_xcr0() making this check unnecessary. Without this variable, the predicates in kvm_load_guest_xcr0 and kvm_put_guest_xcr0 should match. Suggested-by: Sean Christopherson Reviewed-by: Jim Mattson Signed-off-by: Aaron Lewis Change-Id: I7b1eb9b62969d7bbb2850f27e42f863421641b23 Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 16 +++++----------- include/linux/kvm_host.h | 1 - 2 files changed, 5 insertions(+), 12 deletions(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 38131c834091..7141f81141a2 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -811,22 +811,16 @@ EXPORT_SYMBOL_GPL(kvm_lmsw); void kvm_load_guest_xcr0(struct kvm_vcpu *vcpu) { if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE) && - !vcpu->guest_xcr0_loaded) { - /* kvm_set_xcr() also depends on this */ - if (vcpu->arch.xcr0 != host_xcr0) - xsetbv(XCR_XFEATURE_ENABLED_MASK, vcpu->arch.xcr0); - vcpu->guest_xcr0_loaded = 1; - } + vcpu->arch.xcr0 != host_xcr0) + xsetbv(XCR_XFEATURE_ENABLED_MASK, vcpu->arch.xcr0); } EXPORT_SYMBOL_GPL(kvm_load_guest_xcr0); void kvm_put_guest_xcr0(struct kvm_vcpu *vcpu) { - if (vcpu->guest_xcr0_loaded) { - if (vcpu->arch.xcr0 != host_xcr0) - xsetbv(XCR_XFEATURE_ENABLED_MASK, host_xcr0); - vcpu->guest_xcr0_loaded = 0; - } + if (kvm_read_cr4_bits(vcpu, X86_CR4_OSXSAVE) && + vcpu->arch.xcr0 != host_xcr0) + xsetbv(XCR_XFEATURE_ENABLED_MASK, host_xcr0); } EXPORT_SYMBOL_GPL(kvm_put_guest_xcr0); diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 719fc3e15ea4..d2017302996c 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -278,7 +278,6 @@ struct kvm_vcpu { struct mutex mutex; struct kvm_run *run; - int guest_xcr0_loaded; struct swait_queue_head wq; struct pid __rcu *pid; int sigset_active; -- 2.30.2