diff mbox

[v5,4/5] KVM: VMX: Add the algorithm of deliver posted interrupt

Message ID 1362705801-4467-5-git-send-email-yang.z.zhang@intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Zhang, Yang Z March 8, 2013, 1:23 a.m. UTC 
From: Yang Zhang <yang.z.zhang@Intel.com>

Only deliver the posted interrupt when target vcpu is running
and there is no previous interrupt pending in pir.

Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
---
 arch/x86/include/asm/kvm_host.h |    3 ++
 arch/x86/kvm/lapic.c            |   13 ++++++++
 arch/x86/kvm/lapic.h            |    1 +
 arch/x86/kvm/svm.c              |   18 +++++++++++
 arch/x86/kvm/vmx.c              |   60 +++++++++++++++++++++++++++++++++++++++
 virt/kvm/kvm_main.c             |    1 +
 6 files changed, 96 insertions(+), 0 deletions(-)

Comments

Marcelo Tosatti March 8, 2013, 8:21 p.m. UTC | #1 
On Fri, Mar 08, 2013 at 09:23:20AM +0800, Yang Zhang wrote:
> From: Yang Zhang <yang.z.zhang@Intel.com>
> 
> Only deliver the posted interrupt when target vcpu is running
> and there is no previous interrupt pending in pir.
> 
> Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>

> +static bool vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector)
> +{
> +	struct vcpu_vmx *vmx = to_vmx(vcpu);
> +
> +	if (!vmx_vm_has_apicv(vcpu->kvm))
> +		return false;
> +
> +	if (pi_test_and_set_pir(vector, &vmx->pi_desc))
> +		return true;
> +
> +	kvm_make_request(KVM_REQ_EVENT, vcpu);
> +	if ((vcpu->mode == IN_GUEST_MODE)) {
> +		if (!pi_test_and_set_on(&vmx->pi_desc))
> +			apic->send_IPI_mask(get_cpu_mask(vcpu->cpu),
> +					POSTED_INTR_VECTOR);
> +	} else
> +		kvm_vcpu_kick(vcpu);
> +
> +	return true;
> +}

Meaning of return value is unclear.

> +
> +static bool vmx_sync_pir_to_irr(struct kvm_vcpu *vcpu, bool sync)
> +{
> +	struct vcpu_vmx *vmx = to_vmx(vcpu);
> +
> +	if (!vmx_vm_has_apicv(vcpu->kvm))
> +		return false;
> +
> +	if (bitmap_empty((unsigned long *)vmx->pi_desc.pir, 256))
> +		return false;
> +
> +	if (sync)
> +		kvm_apic_update_irr(vcpu, vmx->pi_desc.pir);
> +	return true;
> +}

Please split in two kvm_x86_ops functions: one to query whether PIR is empty the other 
to perform the sync.

Perhaps "->hwapic_has_interrupt" is a good name.

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Zhang, Yang Z March 9, 2013, 1:19 a.m. UTC | #2 
Marcelo Tosatti wrote on 2013-03-09:
> On Fri, Mar 08, 2013 at 09:23:20AM +0800, Yang Zhang wrote:
>> From: Yang Zhang <yang.z.zhang@Intel.com>
>> 
>> Only deliver the posted interrupt when target vcpu is running
>> and there is no previous interrupt pending in pir.
>> 
>> Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
>> 
>> +static bool vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector)
>> +{
>> +	struct vcpu_vmx *vmx = to_vmx(vcpu);
>> +
>> +	if (!vmx_vm_has_apicv(vcpu->kvm))
>> +		return false;
>> +
>> +	if (pi_test_and_set_pir(vector, &vmx->pi_desc))
>> +		return true;
>> +
>> +	kvm_make_request(KVM_REQ_EVENT, vcpu);
>> +	if ((vcpu->mode == IN_GUEST_MODE)) {
>> +		if (!pi_test_and_set_on(&vmx->pi_desc))
>> +			apic->send_IPI_mask(get_cpu_mask(vcpu->cpu),
>> +					POSTED_INTR_VECTOR);
>> +	} else
>> +		kvm_vcpu_kick(vcpu);
>> +
>> +	return true;
>> +}
> 
> Meaning of return value is unclear.
Yes, maybe the function name is confused. how about call it hwapic_deliver_interrupt()?

Or, rollback to the old way:
if(vm_has_apicv)
	deliver_posted_interrupt()
else
	test_and_set_virr(). 

>> +
>> +static bool vmx_sync_pir_to_irr(struct kvm_vcpu *vcpu, bool sync)
>> +{
>> +	struct vcpu_vmx *vmx = to_vmx(vcpu);
>> +
>> +	if (!vmx_vm_has_apicv(vcpu->kvm))
>> +		return false;
>> +
>> +	if (bitmap_empty((unsigned long *)vmx->pi_desc.pir, 256))
>> +		return false;
>> +
>> +	if (sync)
>> +		kvm_apic_update_irr(vcpu, vmx->pi_desc.pir);
>> +	return true;
>> +}
> 
> Please split in two kvm_x86_ops functions: one to query whether PIR is empty
> the other
> to perform the sync.
> 
> Perhaps "->hwapic_has_interrupt" is a good name.
Sure.

Best regards,
Yang

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diff mbox

Patch

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index b8388e9..0a9aeee 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -704,6 +704,9 @@  struct kvm_x86_ops {
 	void (*hwapic_isr_update)(struct kvm *kvm, int isr);
 	void (*load_eoi_exitmap)(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
 	void (*set_virtual_x2apic_mode)(struct kvm_vcpu *vcpu, bool set);
+	bool (*deliver_posted_interrupt)(struct kvm_vcpu *vcpu, int vector);
+	void (*posted_intr_clear_on)(struct kvm_vcpu *vcpu);
+	bool (*sync_pir_to_irr)(struct kvm_vcpu *vcpu, bool sync);
 	int (*set_tss_addr)(struct kvm *kvm, unsigned int addr);
 	int (*get_tdp_level)(void);
 	u64 (*get_mt_mask)(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 02b51dd..b3ea50e 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -357,6 +357,19 @@  static u8 count_vectors(void *bitmap)
 	return count;
 }
 
+void kvm_apic_update_irr(struct kvm_vcpu *vcpu, u32 *pir)
+{
+	u32 i, pir_val;
+	struct kvm_lapic *apic = vcpu->arch.apic;
+
+	for (i = 0; i <= 7; i++) {
+		pir_val = xchg(&pir[i], 0);
+		if (pir_val)
+			*((u32 *)(apic->regs + APIC_IRR + i * 0x10)) |= pir_val;
+	}
+}
+EXPORT_SYMBOL_GPL(kvm_apic_update_irr);
+
 static inline int apic_test_and_set_irr(int vec, struct kvm_lapic *apic)
 {
 	apic->irr_pending = true;
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index 1676d34..e5327be 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -157,5 +157,6 @@  static inline u16 apic_logical_id(struct kvm_apic_map *map, u32 ldr)
 void kvm_calculate_eoi_exitmap(struct kvm_vcpu *vcpu,
 				struct kvm_lapic_irq *irq,
 				u64 *eoi_bitmap);
+void kvm_apic_update_irr(struct kvm_vcpu *vcpu, u32 *pir);
 
 #endif
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index a7d60d7..7a33d75 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -3591,6 +3591,21 @@  static void svm_hwapic_isr_update(struct kvm *kvm, int isr)
 	return;
 }
 
+static bool svm_sync_pir_to_irr(struct kvm_vcpu *vcpu, bool sync)
+{
+	return false;
+}
+
+static bool svm_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector)
+{
+	return false;
+}
+
+static void svm_posted_intr_clear_on(struct kvm_vcpu *vcpu)
+{
+	return;
+}
+
 static int svm_nmi_allowed(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
@@ -4319,6 +4334,9 @@  static struct kvm_x86_ops svm_x86_ops = {
 	.vm_has_apicv = svm_vm_has_apicv,
 	.load_eoi_exitmap = svm_load_eoi_exitmap,
 	.hwapic_isr_update = svm_hwapic_isr_update,
+	.sync_pir_to_irr = svm_sync_pir_to_irr,
+	.deliver_posted_interrupt = svm_deliver_posted_interrupt,
+	.posted_intr_clear_on = svm_posted_intr_clear_on,
 
 	.set_tss_addr = svm_set_tss_addr,
 	.get_tdp_level = get_npt_level,
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 625fd19..5a0be39 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -379,6 +379,17 @@  struct pi_desc {
 	} u;
 } __aligned(64);
 
+static bool pi_test_and_set_on(struct pi_desc *pi_desc)
+{
+	return test_and_set_bit(POSTED_INTR_ON,
+			(unsigned long *)&pi_desc->u.control);
+}
+
+static int pi_test_and_set_pir(int vector, struct pi_desc *pi_desc)
+{
+	return test_and_set_bit(vector, (unsigned long *)pi_desc->pir);
+}
+
 struct vcpu_vmx {
 	struct kvm_vcpu       vcpu;
 	unsigned long         host_rsp;
@@ -3911,6 +3922,52 @@  static int vmx_vm_has_apicv(struct kvm *kvm)
 	return enable_apicv && irqchip_in_kernel(kvm);
 }
 
+static void vmx_posted_intr_clear_on(struct kvm_vcpu *vcpu)
+{
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+
+	if (!vmx_vm_has_apicv(vcpu->kvm))
+		return;
+
+	clear_bit(POSTED_INTR_ON, (unsigned long *)&vmx->pi_desc.u.control);
+}
+
+static bool vmx_deliver_posted_interrupt(struct kvm_vcpu *vcpu, int vector)
+{
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+
+	if (!vmx_vm_has_apicv(vcpu->kvm))
+		return false;
+
+	if (pi_test_and_set_pir(vector, &vmx->pi_desc))
+		return true;
+
+	kvm_make_request(KVM_REQ_EVENT, vcpu);
+	if ((vcpu->mode == IN_GUEST_MODE)) {
+		if (!pi_test_and_set_on(&vmx->pi_desc))
+			apic->send_IPI_mask(get_cpu_mask(vcpu->cpu),
+					POSTED_INTR_VECTOR);
+	} else
+		kvm_vcpu_kick(vcpu);
+
+	return true;
+}
+
+static bool vmx_sync_pir_to_irr(struct kvm_vcpu *vcpu, bool sync)
+{
+	struct vcpu_vmx *vmx = to_vmx(vcpu);
+
+	if (!vmx_vm_has_apicv(vcpu->kvm))
+		return false;
+
+	if (bitmap_empty((unsigned long *)vmx->pi_desc.pir, 256))
+		return false;
+
+	if (sync)
+		kvm_apic_update_irr(vcpu, vmx->pi_desc.pir);
+	return true;
+}
+
 /*
  * Set up the vmcs's constant host-state fields, i.e., host-state fields that
  * will not change in the lifetime of the guest.
@@ -7735,6 +7792,9 @@  static struct kvm_x86_ops vmx_x86_ops = {
 	.load_eoi_exitmap = vmx_load_eoi_exitmap,
 	.hwapic_irr_update = vmx_hwapic_irr_update,
 	.hwapic_isr_update = vmx_hwapic_isr_update,
+	.sync_pir_to_irr = vmx_sync_pir_to_irr,
+	.deliver_posted_interrupt = vmx_deliver_posted_interrupt,
+	.posted_intr_clear_on = vmx_posted_intr_clear_on,
 
 	.set_tss_addr = vmx_set_tss_addr,
 	.get_tdp_level = get_ept_level,
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index adc68fe..cd73e0e 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1692,6 +1692,7 @@  void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
 			smp_send_reschedule(cpu);
 	put_cpu();
 }
+EXPORT_SYMBOL_GPL(kvm_vcpu_kick);
 #endif /* !CONFIG_S390 */
 
 void kvm_resched(struct kvm_vcpu *vcpu)