From: Nicolai Stange Date: Sat, 21 Jul 2018 20:35:28 +0000 (+0200) Subject: x86/KVM/VMX: Move the l1tf_flush_l1d test to vmx_l1d_flush() X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=0d6b3085975fafd909d26d37310c641f8e5e1be9;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git x86/KVM/VMX: Move the l1tf_flush_l1d test to vmx_l1d_flush() commit 5b6ccc6c3b1a477fbac9ec97a0b4c1c48e765209 upstream Currently, vmx_vcpu_run() checks if l1tf_flush_l1d is set and invokes vmx_l1d_flush() if so. This test is unncessary for the "always flush L1D" mode. Move the check to vmx_l1d_flush()'s conditional mode code path. Notes: - vmx_l1d_flush() is likely to get inlined anyway and thus, there's no extra function call. - This inverts the (static) branch prediction, but there hadn't been any explicit likely()/unlikely() annotations before and so it stays as is. Signed-off-by: Nicolai Stange Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 785d8169ecaa..60ffeb3c60ee 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -9168,12 +9168,16 @@ static void vmx_l1d_flush(struct kvm_vcpu *vcpu) * 'always' */ if (static_branch_likely(&vmx_l1d_flush_cond)) { + bool flush_l1d = vcpu->arch.l1tf_flush_l1d; + /* * Clear the flush bit, it gets set again either from * vcpu_run() or from one of the unsafe VMEXIT * handlers. */ vcpu->arch.l1tf_flush_l1d = false; + if (!flush_l1d) + return; } vcpu->stat.l1d_flush++; @@ -9703,10 +9707,8 @@ static void __noclone vmx_vcpu_run(struct kvm_vcpu *vcpu) vmx->__launched = vmx->loaded_vmcs->launched; - if (static_branch_unlikely(&vmx_l1d_should_flush)) { - if (vcpu->arch.l1tf_flush_l1d) - vmx_l1d_flush(vcpu); - } + if (static_branch_unlikely(&vmx_l1d_should_flush)) + vmx_l1d_flush(vcpu); asm( /* Store host registers */