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| author | Longpeng(Mike) <longpeng2@huawei.com> | 2017-08-08 12:05:33 +0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2017-08-08 10:57:43 +0200 |
| commit | de63ad4cf4973462953c29c363f3cfa7117c2b2d (patch) | |
| tree | b269d3a1c04045d9f4f7005f8004f7da082bf0be | |
| parent | 199b5763d329b43c88f6ad539db8a6c6b42f8edb (diff) | |
| download | linux-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>
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 3 | ||||
| -rw-r--r-- | arch/x86/kvm/hyperv.c | 2 | ||||
| -rw-r--r-- | arch/x86/kvm/svm.c | 5 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx.c | 8 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 7 |
5 files changed, 21 insertions, 4 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 87ac4fba6d8e..1679aabcabe5 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -688,6 +688,9 @@ struct kvm_vcpu_arch { /* GPA available (AMD only) */ bool gpa_available; + + /* be preempted when it's in kernel-mode(cpl=0) */ + bool preempted_in_kernel; }; struct kvm_lpage_info { 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) |