summaryrefslogtreecommitdiffstats
path: root/arch/x86/kvm
diff options
context:
space:
mode:
authorLongpeng(Mike) <longpeng2@huawei.com>2017-08-08 12:05:33 +0800
committerPaolo Bonzini <pbonzini@redhat.com>2017-08-08 10:57:43 +0200
commitde63ad4cf4973462953c29c363f3cfa7117c2b2d (patch)
treeb269d3a1c04045d9f4f7005f8004f7da082bf0be /arch/x86/kvm
parent199b5763d329b43c88f6ad539db8a6c6b42f8edb (diff)
downloadlinux-de63ad4cf4973462953c29c363f3cfa7117c2b2d.tar.bz2
KVM: X86: implement the logic for spinlock optimization
get_cpl requires vcpu_load, so we must cache the result (whether the vcpu was preempted when its cpl=0) in kvm_vcpu_arch. Signed-off-by: Longpeng(Mike) <longpeng2@huawei.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm')
-rw-r--r--arch/x86/kvm/hyperv.c2
-rw-r--r--arch/x86/kvm/svm.c5
-rw-r--r--arch/x86/kvm/vmx.c8
-rw-r--r--arch/x86/kvm/x86.c7
4 files changed, 18 insertions, 4 deletions
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 5243d54f73ab..dc97f2544b6f 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1274,7 +1274,7 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu)
switch (code) {
case HVCALL_NOTIFY_LONG_SPIN_WAIT:
- kvm_vcpu_on_spin(vcpu, false);
+ kvm_vcpu_on_spin(vcpu, true);
break;
case HVCALL_POST_MESSAGE:
case HVCALL_SIGNAL_EVENT:
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 0cc486fd9871..1fa9ee5660f4 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -3749,7 +3749,10 @@ static int interrupt_window_interception(struct vcpu_svm *svm)
static int pause_interception(struct vcpu_svm *svm)
{
- kvm_vcpu_on_spin(&svm->vcpu, false);
+ struct kvm_vcpu *vcpu = &svm->vcpu;
+ bool in_kernel = (svm_get_cpl(vcpu) == 0);
+
+ kvm_vcpu_on_spin(vcpu, in_kernel);
return 1;
}
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index fef784c22190..46d08b389e36 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -6781,7 +6781,13 @@ static int handle_pause(struct kvm_vcpu *vcpu)
if (ple_gap)
grow_ple_window(vcpu);
- kvm_vcpu_on_spin(vcpu, false);
+ /*
+ * Intel sdm vol3 ch-25.1.3 says: The "PAUSE-loop exiting"
+ * VM-execution control is ignored if CPL > 0. OTOH, KVM
+ * never set PAUSE_EXITING and just set PLE if supported,
+ * so the vcpu must be CPL=0 if it gets a PAUSE exit.
+ */
+ kvm_vcpu_on_spin(vcpu, true);
return kvm_skip_emulated_instruction(vcpu);
}
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 6125e1743b69..69b72c9e1f12 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2873,6 +2873,10 @@ static void kvm_steal_time_set_preempted(struct kvm_vcpu *vcpu)
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
{
int idx;
+
+ if (vcpu->preempted)
+ vcpu->arch.preempted_in_kernel = !kvm_x86_ops->get_cpl(vcpu);
+
/*
* Disable page faults because we're in atomic context here.
* kvm_write_guest_offset_cached() would call might_fault()
@@ -7985,6 +7989,7 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
kvm_pmu_init(vcpu);
vcpu->arch.pending_external_vector = -1;
+ vcpu->arch.preempted_in_kernel = false;
kvm_hv_vcpu_init(vcpu);
@@ -8434,7 +8439,7 @@ int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
{
- return false;
+ return vcpu->arch.preempted_in_kernel;
}
int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)