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* [PATCH 1/2] KVM: X86: Filter the broadcast dest for IPI fastpath
@ 2020-03-27  6:23 Wanpeng Li
  2020-03-27  6:24 ` [PATCH 2/2] KVM: LAPIC: Don't need to clear IPI delivery status for x2apic Wanpeng Li
  2020-03-27  9:00 ` [PATCH 1/2] KVM: X86: Filter the broadcast dest for IPI fastpath Vitaly Kuznetsov
  0 siblings, 2 replies; 5+ messages in thread
From: Wanpeng Li @ 2020-03-27  6:23 UTC (permalink / raw)
  To: linux-kernel, kvm
  Cc: Paolo Bonzini, Sean Christopherson, Vitaly Kuznetsov, Wanpeng Li,
	Jim Mattson, Joerg Roedel

From: Wanpeng Li <wanpengli@tencent.com>

Except destination shorthand, a destination value 0xffffffff is used to 
broadcast interrupts, let's also filter this for single target IPI fastpath.

Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
---
 arch/x86/kvm/lapic.c | 3 ---
 arch/x86/kvm/lapic.h | 3 +++
 arch/x86/kvm/x86.c   | 3 ++-
 3 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index a38f1a8..88929b1 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -59,9 +59,6 @@
 #define MAX_APIC_VECTOR			256
 #define APIC_VECTORS_PER_REG		32
 
-#define APIC_BROADCAST			0xFF
-#define X2APIC_BROADCAST		0xFFFFFFFFul
-
 static bool lapic_timer_advance_dynamic __read_mostly;
 #define LAPIC_TIMER_ADVANCE_ADJUST_MIN	100	/* clock cycles */
 #define LAPIC_TIMER_ADVANCE_ADJUST_MAX	10000	/* clock cycles */
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index bc76860..25b77a6 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -17,6 +17,9 @@
 #define APIC_BUS_CYCLE_NS       1
 #define APIC_BUS_FREQUENCY      (1000000000ULL / APIC_BUS_CYCLE_NS)
 
+#define APIC_BROADCAST			0xFF
+#define X2APIC_BROADCAST		0xFFFFFFFFul
+
 enum lapic_mode {
 	LAPIC_MODE_DISABLED = 0,
 	LAPIC_MODE_INVALID = X2APIC_ENABLE,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c4bb7d8..495709f 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1559,7 +1559,8 @@ static int handle_fastpath_set_x2apic_icr_irqoff(struct kvm_vcpu *vcpu, u64 data
 
 	if (((data & APIC_SHORT_MASK) == APIC_DEST_NOSHORT) &&
 		((data & APIC_DEST_MASK) == APIC_DEST_PHYSICAL) &&
-		((data & APIC_MODE_MASK) == APIC_DM_FIXED)) {
+		((data & APIC_MODE_MASK) == APIC_DM_FIXED) &&
+		((u32)(data >> 32) != X2APIC_BROADCAST)) {
 
 		data &= ~(1 << 12);
 		kvm_apic_send_ipi(vcpu->arch.apic, (u32)data, (u32)(data >> 32));
-- 
2.7.4


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH 2/2] KVM: LAPIC: Don't need to clear IPI delivery status for x2apic
  2020-03-27  6:23 [PATCH 1/2] KVM: X86: Filter the broadcast dest for IPI fastpath Wanpeng Li
@ 2020-03-27  6:24 ` Wanpeng Li
  2020-03-27  9:06   ` Vitaly Kuznetsov
  2020-03-27  9:00 ` [PATCH 1/2] KVM: X86: Filter the broadcast dest for IPI fastpath Vitaly Kuznetsov
  1 sibling, 1 reply; 5+ messages in thread
From: Wanpeng Li @ 2020-03-27  6:24 UTC (permalink / raw)
  To: linux-kernel, kvm
  Cc: Paolo Bonzini, Sean Christopherson, Vitaly Kuznetsov, Wanpeng Li,
	Jim Mattson, Joerg Roedel

From: Wanpeng Li <wanpengli@tencent.com>

IPI delivery status field is not present for x2apic, don't need 
to clear IPI delivery status for x2apic.

Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
---
 arch/x86/kvm/lapic.c | 3 ++-
 arch/x86/kvm/x86.c   | 1 -
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 88929b1..f6d69e2 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1942,7 +1942,8 @@ int kvm_lapic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
 	}
 	case APIC_ICR:
 		/* No delay here, so we always clear the pending bit */
-		val &= ~(1 << 12);
+		if (!apic_x2apic_mode(apic))
+			val &= ~(1 << 12);
 		kvm_apic_send_ipi(apic, val, kvm_lapic_get_reg(apic, APIC_ICR2));
 		kvm_lapic_set_reg(apic, APIC_ICR, val);
 		break;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 495709f..6ced0e1 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1562,7 +1562,6 @@ static int handle_fastpath_set_x2apic_icr_irqoff(struct kvm_vcpu *vcpu, u64 data
 		((data & APIC_MODE_MASK) == APIC_DM_FIXED) &&
 		((u32)(data >> 32) != X2APIC_BROADCAST)) {
 
-		data &= ~(1 << 12);
 		kvm_apic_send_ipi(vcpu->arch.apic, (u32)data, (u32)(data >> 32));
 		kvm_lapic_set_reg(vcpu->arch.apic, APIC_ICR2, (u32)(data >> 32));
 		kvm_lapic_set_reg(vcpu->arch.apic, APIC_ICR, (u32)data);
-- 
2.7.4


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* Re: [PATCH 1/2] KVM: X86: Filter the broadcast dest for IPI fastpath
  2020-03-27  6:23 [PATCH 1/2] KVM: X86: Filter the broadcast dest for IPI fastpath Wanpeng Li
  2020-03-27  6:24 ` [PATCH 2/2] KVM: LAPIC: Don't need to clear IPI delivery status for x2apic Wanpeng Li
@ 2020-03-27  9:00 ` Vitaly Kuznetsov
  1 sibling, 0 replies; 5+ messages in thread
From: Vitaly Kuznetsov @ 2020-03-27  9:00 UTC (permalink / raw)
  To: Wanpeng Li
  Cc: Paolo Bonzini, Sean Christopherson, Wanpeng Li, Jim Mattson,
	Joerg Roedel, linux-kernel, kvm

Wanpeng Li <kernellwp@gmail.com> writes:

> From: Wanpeng Li <wanpengli@tencent.com>
>
> Except destination shorthand, a destination value 0xffffffff is used to 
> broadcast interrupts, let's also filter this for single target IPI fastpath.
>
> Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
> ---
>  arch/x86/kvm/lapic.c | 3 ---
>  arch/x86/kvm/lapic.h | 3 +++
>  arch/x86/kvm/x86.c   | 3 ++-
>  3 files changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> index a38f1a8..88929b1 100644
> --- a/arch/x86/kvm/lapic.c
> +++ b/arch/x86/kvm/lapic.c
> @@ -59,9 +59,6 @@
>  #define MAX_APIC_VECTOR			256
>  #define APIC_VECTORS_PER_REG		32
>  
> -#define APIC_BROADCAST			0xFF
> -#define X2APIC_BROADCAST		0xFFFFFFFFul
> -
>  static bool lapic_timer_advance_dynamic __read_mostly;
>  #define LAPIC_TIMER_ADVANCE_ADJUST_MIN	100	/* clock cycles */
>  #define LAPIC_TIMER_ADVANCE_ADJUST_MAX	10000	/* clock cycles */
> diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
> index bc76860..25b77a6 100644
> --- a/arch/x86/kvm/lapic.h
> +++ b/arch/x86/kvm/lapic.h
> @@ -17,6 +17,9 @@
>  #define APIC_BUS_CYCLE_NS       1
>  #define APIC_BUS_FREQUENCY      (1000000000ULL / APIC_BUS_CYCLE_NS)
>  
> +#define APIC_BROADCAST			0xFF
> +#define X2APIC_BROADCAST		0xFFFFFFFFul
> +
>  enum lapic_mode {
>  	LAPIC_MODE_DISABLED = 0,
>  	LAPIC_MODE_INVALID = X2APIC_ENABLE,
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index c4bb7d8..495709f 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -1559,7 +1559,8 @@ static int handle_fastpath_set_x2apic_icr_irqoff(struct kvm_vcpu *vcpu, u64 data
>  
>  	if (((data & APIC_SHORT_MASK) == APIC_DEST_NOSHORT) &&
>  		((data & APIC_DEST_MASK) == APIC_DEST_PHYSICAL) &&
> -		((data & APIC_MODE_MASK) == APIC_DM_FIXED)) {
> +		((data & APIC_MODE_MASK) == APIC_DM_FIXED) &&
> +		((u32)(data >> 32) != X2APIC_BROADCAST)) {
>  
>  		data &= ~(1 << 12);
>  		kvm_apic_send_ipi(vcpu->arch.apic, (u32)data, (u32)(data >> 32));

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>

-- 
Vitaly


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH 2/2] KVM: LAPIC: Don't need to clear IPI delivery status for x2apic
  2020-03-27  6:24 ` [PATCH 2/2] KVM: LAPIC: Don't need to clear IPI delivery status for x2apic Wanpeng Li
@ 2020-03-27  9:06   ` Vitaly Kuznetsov
  2020-03-27  9:27     ` Wanpeng Li
  0 siblings, 1 reply; 5+ messages in thread
From: Vitaly Kuznetsov @ 2020-03-27  9:06 UTC (permalink / raw)
  To: Wanpeng Li, linux-kernel, kvm
  Cc: Paolo Bonzini, Sean Christopherson, Wanpeng Li, Jim Mattson,
	Joerg Roedel

Wanpeng Li <kernellwp@gmail.com> writes:

> From: Wanpeng Li <wanpengli@tencent.com>
>
> IPI delivery status field is not present for x2apic, don't need 
> to clear IPI delivery status for x2apic.
>
> Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
> ---
>  arch/x86/kvm/lapic.c | 3 ++-
>  arch/x86/kvm/x86.c   | 1 -
>  2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> index 88929b1..f6d69e2 100644
> --- a/arch/x86/kvm/lapic.c
> +++ b/arch/x86/kvm/lapic.c
> @@ -1942,7 +1942,8 @@ int kvm_lapic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
>  	}
>  	case APIC_ICR:
>  		/* No delay here, so we always clear the pending bit */

'Always' in the comment above now reads a bit odd, I'd suggest modifying
it to 'Immediately clear Delivery Status field in xAPIC mode' - or just
drop it altogeter.

> -		val &= ~(1 << 12);
> +		if (!apic_x2apic_mode(apic))
> +			val &= ~(1 << 12);
>  		kvm_apic_send_ipi(apic, val, kvm_lapic_get_reg(apic, APIC_ICR2));
>  		kvm_lapic_set_reg(apic, APIC_ICR, val);
>  		break;
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 495709f..6ced0e1 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -1562,7 +1562,6 @@ static int handle_fastpath_set_x2apic_icr_irqoff(struct kvm_vcpu *vcpu, u64 data
>  		((data & APIC_MODE_MASK) == APIC_DM_FIXED) &&
>  		((u32)(data >> 32) != X2APIC_BROADCAST)) {
>  
> -		data &= ~(1 << 12);
>  		kvm_apic_send_ipi(vcpu->arch.apic, (u32)data, (u32)(data >> 32));
>  		kvm_lapic_set_reg(vcpu->arch.apic, APIC_ICR2, (u32)(data >> 32));
>  		kvm_lapic_set_reg(vcpu->arch.apic, APIC_ICR, (u32)data);

Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>

-- 
Vitaly


^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH 2/2] KVM: LAPIC: Don't need to clear IPI delivery status for x2apic
  2020-03-27  9:06   ` Vitaly Kuznetsov
@ 2020-03-27  9:27     ` Wanpeng Li
  0 siblings, 0 replies; 5+ messages in thread
From: Wanpeng Li @ 2020-03-27  9:27 UTC (permalink / raw)
  To: Vitaly Kuznetsov
  Cc: LKML, kvm, Paolo Bonzini, Sean Christopherson, Wanpeng Li,
	Jim Mattson, Joerg Roedel

On Fri, 27 Mar 2020 at 17:07, Vitaly Kuznetsov <vkuznets@redhat.com> wrote:
>
> Wanpeng Li <kernellwp@gmail.com> writes:
>
> > From: Wanpeng Li <wanpengli@tencent.com>
> >
> > IPI delivery status field is not present for x2apic, don't need
> > to clear IPI delivery status for x2apic.
> >
> > Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
> > ---
> >  arch/x86/kvm/lapic.c | 3 ++-
> >  arch/x86/kvm/x86.c   | 1 -
> >  2 files changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> > index 88929b1..f6d69e2 100644
> > --- a/arch/x86/kvm/lapic.c
> > +++ b/arch/x86/kvm/lapic.c
> > @@ -1942,7 +1942,8 @@ int kvm_lapic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
> >       }
> >       case APIC_ICR:
> >               /* No delay here, so we always clear the pending bit */
>
> 'Always' in the comment above now reads a bit odd, I'd suggest modifying
> it to 'Immediately clear Delivery Status field in xAPIC mode' - or just
> drop it altogeter.

Thank you for your review, I guess Paolo can do it when apply.

    Wanpeng

>
> > -             val &= ~(1 << 12);
> > +             if (!apic_x2apic_mode(apic))
> > +                     val &= ~(1 << 12);
> >               kvm_apic_send_ipi(apic, val, kvm_lapic_get_reg(apic, APIC_ICR2));
> >               kvm_lapic_set_reg(apic, APIC_ICR, val);
> >               break;
> > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> > index 495709f..6ced0e1 100644
> > --- a/arch/x86/kvm/x86.c
> > +++ b/arch/x86/kvm/x86.c
> > @@ -1562,7 +1562,6 @@ static int handle_fastpath_set_x2apic_icr_irqoff(struct kvm_vcpu *vcpu, u64 data
> >               ((data & APIC_MODE_MASK) == APIC_DM_FIXED) &&
> >               ((u32)(data >> 32) != X2APIC_BROADCAST)) {
> >
> > -             data &= ~(1 << 12);
> >               kvm_apic_send_ipi(vcpu->arch.apic, (u32)data, (u32)(data >> 32));
> >               kvm_lapic_set_reg(vcpu->arch.apic, APIC_ICR2, (u32)(data >> 32));
> >               kvm_lapic_set_reg(vcpu->arch.apic, APIC_ICR, (u32)data);
>
> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
>
> --
> Vitaly
>

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2020-03-27  9:27 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz / follow: Atom feed)
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2020-03-27  6:23 [PATCH 1/2] KVM: X86: Filter the broadcast dest for IPI fastpath Wanpeng Li
2020-03-27  6:24 ` [PATCH 2/2] KVM: LAPIC: Don't need to clear IPI delivery status for x2apic Wanpeng Li
2020-03-27  9:06   ` Vitaly Kuznetsov
2020-03-27  9:27     ` Wanpeng Li
2020-03-27  9:00 ` [PATCH 1/2] KVM: X86: Filter the broadcast dest for IPI fastpath Vitaly Kuznetsov

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