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* [PATCH 1/2] KVM: arm/arm64: vgic: move DEBUG_SPINLOCK_BUG_ON to vgic.h
@ 2018-08-03 13:57 Jia He
  2018-08-03 13:57 ` [PATCH 2/2] KVM: arm/arm64: vgic: no need to call spin_lock_irqsave/restore when irq is disabled Jia He
  0 siblings, 1 reply; 3+ messages in thread
From: Jia He @ 2018-08-03 13:57 UTC (permalink / raw)
  To: Christoffer Dall, Marc Zyngier, Catalin Marinas, Eric Auger,
	Ard Biesheuvel
  Cc: Jia He, Andre Przywara, Greg Kroah-Hartman, linux-arm-kernel,
	kvmarm, linux-kernel, Jia He

This is to let DEBUG_SPINLOCK_BUG_ON be commonly used in vgic-v2 and
vgic-v3.

Signed-off-by: Jia He <jia.he@hxt-semitech.com>
---
 virt/kvm/arm/vgic/vgic.c | 6 ------
 virt/kvm/arm/vgic/vgic.h | 6 ++++++
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c
index 33c8325..c22cea6 100644
--- a/virt/kvm/arm/vgic/vgic.c
+++ b/virt/kvm/arm/vgic/vgic.c
@@ -28,12 +28,6 @@
 #define CREATE_TRACE_POINTS
 #include "trace.h"
 
-#ifdef CONFIG_DEBUG_SPINLOCK
-#define DEBUG_SPINLOCK_BUG_ON(p) BUG_ON(p)
-#else
-#define DEBUG_SPINLOCK_BUG_ON(p)
-#endif
-
 struct vgic_global kvm_vgic_global_state __ro_after_init = {
 	.gicv3_cpuif = STATIC_KEY_FALSE_INIT,
 };
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index ead00b2..ea51fcc 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -103,6 +103,12 @@
 #define KVM_VGIC_V3_RDIST_COUNT_MASK	GENMASK_ULL(63, 52)
 #define KVM_VGIC_V3_RDIST_COUNT_SHIFT	52
 
+#ifdef CONFIG_DEBUG_SPINLOCK
+#define DEBUG_SPINLOCK_BUG_ON(p) BUG_ON(p)
+#else
+#define DEBUG_SPINLOCK_BUG_ON(p)
+#endif
+
 /* Requires the irq_lock to be held by the caller. */
 static inline bool irq_is_pending(struct vgic_irq *irq)
 {
-- 
1.8.3.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread
* [PATCH 2/2] KVM: arm/arm64: vgic: no need to call spin_lock_irqsave/restore when irq is disabled
  2018-08-03 13:57 [PATCH 1/2] KVM: arm/arm64: vgic: move DEBUG_SPINLOCK_BUG_ON to vgic.h Jia He
@ 2018-08-03 13:57 ` Jia He
  2018-08-06 14:13   ` Christoffer Dall
  0 siblings, 1 reply; 3+ messages in thread
From: Jia He @ 2018-08-03 13:57 UTC (permalink / raw)
  To: Christoffer Dall, Marc Zyngier, Catalin Marinas, Eric Auger,
	Ard Biesheuvel
  Cc: Jia He, Andre Przywara, Greg Kroah-Hartman, linux-arm-kernel,
	kvmarm, linux-kernel, Jia He

Because kvm_vgic_sync_hwstate currently is definitly in the context
which irq is disabled (local_irq_disable/enable). There is no need to
call spin_lock_irqsave/restore in vgic_fold_lr_state and vgic_prune_ap_list

This patch replace them with the spin_lock/unlock no irq version

Signed-off-by: Jia He <jia.he@hxt-semitech.com>
---
 virt/kvm/arm/vgic/vgic-v2.c |  7 ++++---
 virt/kvm/arm/vgic/vgic-v3.c |  7 ++++---
 virt/kvm/arm/vgic/vgic.c    | 13 +++++++------
 3 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic-v2.c b/virt/kvm/arm/vgic/vgic-v2.c
index a5f2e44..487f5f2 100644
--- a/virt/kvm/arm/vgic/vgic-v2.c
+++ b/virt/kvm/arm/vgic/vgic-v2.c
@@ -62,7 +62,8 @@ void vgic_v2_fold_lr_state(struct kvm_vcpu *vcpu)
 	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
 	struct vgic_v2_cpu_if *cpuif = &vgic_cpu->vgic_v2;
 	int lr;
-	unsigned long flags;
+
+	DEBUG_SPINLOCK_BUG_ON(!irqs_disabled());
 
 	cpuif->vgic_hcr &= ~GICH_HCR_UIE;
 
@@ -83,7 +84,7 @@ void vgic_v2_fold_lr_state(struct kvm_vcpu *vcpu)
 
 		irq = vgic_get_irq(vcpu->kvm, vcpu, intid);
 
-		spin_lock_irqsave(&irq->irq_lock, flags);
+		spin_lock(&irq->irq_lock);
 
 		/* Always preserve the active bit */
 		irq->active = !!(val & GICH_LR_ACTIVE_BIT);
@@ -126,7 +127,7 @@ void vgic_v2_fold_lr_state(struct kvm_vcpu *vcpu)
 				vgic_irq_set_phys_active(irq, false);
 		}
 
-		spin_unlock_irqrestore(&irq->irq_lock, flags);
+		spin_unlock(&irq->irq_lock);
 		vgic_put_irq(vcpu->kvm, irq);
 	}
 
diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index cdce653..b66b513 100644
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -46,7 +46,8 @@ void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu)
 	struct vgic_v3_cpu_if *cpuif = &vgic_cpu->vgic_v3;
 	u32 model = vcpu->kvm->arch.vgic.vgic_model;
 	int lr;
-	unsigned long flags;
+
+	DEBUG_SPINLOCK_BUG_ON(!irqs_disabled());
 
 	cpuif->vgic_hcr &= ~ICH_HCR_UIE;
 
@@ -75,7 +76,7 @@ void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu)
 		if (!irq)	/* An LPI could have been unmapped. */
 			continue;
 
-		spin_lock_irqsave(&irq->irq_lock, flags);
+		spin_lock(&irq->irq_lock);
 
 		/* Always preserve the active bit */
 		irq->active = !!(val & ICH_LR_ACTIVE_BIT);
@@ -118,7 +119,7 @@ void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu)
 				vgic_irq_set_phys_active(irq, false);
 		}
 
-		spin_unlock_irqrestore(&irq->irq_lock, flags);
+		spin_unlock(&irq->irq_lock);
 		vgic_put_irq(vcpu->kvm, irq);
 	}
 
diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c
index c22cea6..7cfdfbc 100644
--- a/virt/kvm/arm/vgic/vgic.c
+++ b/virt/kvm/arm/vgic/vgic.c
@@ -593,10 +593,11 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu)
 {
 	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
 	struct vgic_irq *irq, *tmp;
-	unsigned long flags;
+
+	DEBUG_SPINLOCK_BUG_ON(!irqs_disabled());
 
 retry:
-	spin_lock_irqsave(&vgic_cpu->ap_list_lock, flags);
+	spin_lock(&vgic_cpu->ap_list_lock);
 
 	list_for_each_entry_safe(irq, tmp, &vgic_cpu->ap_list_head, ap_list) {
 		struct kvm_vcpu *target_vcpu, *vcpuA, *vcpuB;
@@ -637,7 +638,7 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu)
 		/* This interrupt looks like it has to be migrated. */
 
 		spin_unlock(&irq->irq_lock);
-		spin_unlock_irqrestore(&vgic_cpu->ap_list_lock, flags);
+		spin_unlock(&vgic_cpu->ap_list_lock);
 
 		/*
 		 * Ensure locking order by always locking the smallest
@@ -651,7 +652,7 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu)
 			vcpuB = vcpu;
 		}
 
-		spin_lock_irqsave(&vcpuA->arch.vgic_cpu.ap_list_lock, flags);
+		spin_lock(&vcpuA->arch.vgic_cpu.ap_list_lock);
 		spin_lock_nested(&vcpuB->arch.vgic_cpu.ap_list_lock,
 				 SINGLE_DEPTH_NESTING);
 		spin_lock(&irq->irq_lock);
@@ -676,7 +677,7 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu)
 
 		spin_unlock(&irq->irq_lock);
 		spin_unlock(&vcpuB->arch.vgic_cpu.ap_list_lock);
-		spin_unlock_irqrestore(&vcpuA->arch.vgic_cpu.ap_list_lock, flags);
+		spin_unlock(&vcpuA->arch.vgic_cpu.ap_list_lock);
 
 		if (target_vcpu_needs_kick) {
 			kvm_make_request(KVM_REQ_IRQ_PENDING, target_vcpu);
@@ -686,7 +687,7 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu)
 		goto retry;
 	}
 
-	spin_unlock_irqrestore(&vgic_cpu->ap_list_lock, flags);
+	spin_unlock(&vgic_cpu->ap_list_lock);
 }
 
 static inline void vgic_fold_lr_state(struct kvm_vcpu *vcpu)
-- 
1.8.3.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread
* Re: [PATCH 2/2] KVM: arm/arm64: vgic: no need to call spin_lock_irqsave/restore when irq is disabled
  2018-08-03 13:57 ` [PATCH 2/2] KVM: arm/arm64: vgic: no need to call spin_lock_irqsave/restore when irq is disabled Jia He
@ 2018-08-06 14:13   ` Christoffer Dall
  0 siblings, 0 replies; 3+ messages in thread
From: Christoffer Dall @ 2018-08-06 14:13 UTC (permalink / raw)
  To: Jia He
  Cc: Marc Zyngier, Catalin Marinas, Eric Auger, Ard Biesheuvel,
	Andre Przywara, Greg Kroah-Hartman, linux-arm-kernel, kvmarm,
	linux-kernel, Jia He

On Fri, Aug 03, 2018 at 09:57:04PM +0800, Jia He wrote:
> Because kvm_vgic_sync_hwstate currently is definitly in the context
> which irq is disabled (local_irq_disable/enable). There is no need to
> call spin_lock_irqsave/restore in vgic_fold_lr_state and vgic_prune_ap_list
> 
> This patch replace them with the spin_lock/unlock no irq version
> 
> Signed-off-by: Jia He <jia.he@hxt-semitech.com>
> ---
>  virt/kvm/arm/vgic/vgic-v2.c |  7 ++++---
>  virt/kvm/arm/vgic/vgic-v3.c |  7 ++++---
>  virt/kvm/arm/vgic/vgic.c    | 13 +++++++------
>  3 files changed, 15 insertions(+), 12 deletions(-)
> 
> diff --git a/virt/kvm/arm/vgic/vgic-v2.c b/virt/kvm/arm/vgic/vgic-v2.c
> index a5f2e44..487f5f2 100644
> --- a/virt/kvm/arm/vgic/vgic-v2.c
> +++ b/virt/kvm/arm/vgic/vgic-v2.c
> @@ -62,7 +62,8 @@ void vgic_v2_fold_lr_state(struct kvm_vcpu *vcpu)
>  	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
>  	struct vgic_v2_cpu_if *cpuif = &vgic_cpu->vgic_v2;
>  	int lr;
> -	unsigned long flags;
> +
> +	DEBUG_SPINLOCK_BUG_ON(!irqs_disabled());
>  
>  	cpuif->vgic_hcr &= ~GICH_HCR_UIE;
>  
> @@ -83,7 +84,7 @@ void vgic_v2_fold_lr_state(struct kvm_vcpu *vcpu)
>  
>  		irq = vgic_get_irq(vcpu->kvm, vcpu, intid);
>  
> -		spin_lock_irqsave(&irq->irq_lock, flags);
> +		spin_lock(&irq->irq_lock);
>  
>  		/* Always preserve the active bit */
>  		irq->active = !!(val & GICH_LR_ACTIVE_BIT);
> @@ -126,7 +127,7 @@ void vgic_v2_fold_lr_state(struct kvm_vcpu *vcpu)
>  				vgic_irq_set_phys_active(irq, false);
>  		}
>  
> -		spin_unlock_irqrestore(&irq->irq_lock, flags);
> +		spin_unlock(&irq->irq_lock);
>  		vgic_put_irq(vcpu->kvm, irq);
>  	}
>  
> diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
> index cdce653..b66b513 100644
> --- a/virt/kvm/arm/vgic/vgic-v3.c
> +++ b/virt/kvm/arm/vgic/vgic-v3.c
> @@ -46,7 +46,8 @@ void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu)
>  	struct vgic_v3_cpu_if *cpuif = &vgic_cpu->vgic_v3;
>  	u32 model = vcpu->kvm->arch.vgic.vgic_model;
>  	int lr;
> -	unsigned long flags;
> +
> +	DEBUG_SPINLOCK_BUG_ON(!irqs_disabled());
>  
>  	cpuif->vgic_hcr &= ~ICH_HCR_UIE;
>  
> @@ -75,7 +76,7 @@ void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu)
>  		if (!irq)	/* An LPI could have been unmapped. */
>  			continue;
>  
> -		spin_lock_irqsave(&irq->irq_lock, flags);
> +		spin_lock(&irq->irq_lock);
>  
>  		/* Always preserve the active bit */
>  		irq->active = !!(val & ICH_LR_ACTIVE_BIT);
> @@ -118,7 +119,7 @@ void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu)
>  				vgic_irq_set_phys_active(irq, false);
>  		}
>  
> -		spin_unlock_irqrestore(&irq->irq_lock, flags);
> +		spin_unlock(&irq->irq_lock);
>  		vgic_put_irq(vcpu->kvm, irq);
>  	}
>  
> diff --git a/virt/kvm/arm/vgic/vgic.c b/virt/kvm/arm/vgic/vgic.c
> index c22cea6..7cfdfbc 100644
> --- a/virt/kvm/arm/vgic/vgic.c
> +++ b/virt/kvm/arm/vgic/vgic.c
> @@ -593,10 +593,11 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu)
>  {
>  	struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
>  	struct vgic_irq *irq, *tmp;
> -	unsigned long flags;
> +
> +	DEBUG_SPINLOCK_BUG_ON(!irqs_disabled());
>  
>  retry:
> -	spin_lock_irqsave(&vgic_cpu->ap_list_lock, flags);
> +	spin_lock(&vgic_cpu->ap_list_lock);
>  
>  	list_for_each_entry_safe(irq, tmp, &vgic_cpu->ap_list_head, ap_list) {
>  		struct kvm_vcpu *target_vcpu, *vcpuA, *vcpuB;
> @@ -637,7 +638,7 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu)
>  		/* This interrupt looks like it has to be migrated. */
>  
>  		spin_unlock(&irq->irq_lock);
> -		spin_unlock_irqrestore(&vgic_cpu->ap_list_lock, flags);
> +		spin_unlock(&vgic_cpu->ap_list_lock);
>  
>  		/*
>  		 * Ensure locking order by always locking the smallest
> @@ -651,7 +652,7 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu)
>  			vcpuB = vcpu;
>  		}
>  
> -		spin_lock_irqsave(&vcpuA->arch.vgic_cpu.ap_list_lock, flags);
> +		spin_lock(&vcpuA->arch.vgic_cpu.ap_list_lock);
>  		spin_lock_nested(&vcpuB->arch.vgic_cpu.ap_list_lock,
>  				 SINGLE_DEPTH_NESTING);
>  		spin_lock(&irq->irq_lock);
> @@ -676,7 +677,7 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu)
>  
>  		spin_unlock(&irq->irq_lock);
>  		spin_unlock(&vcpuB->arch.vgic_cpu.ap_list_lock);
> -		spin_unlock_irqrestore(&vcpuA->arch.vgic_cpu.ap_list_lock, flags);
> +		spin_unlock(&vcpuA->arch.vgic_cpu.ap_list_lock);
>  
>  		if (target_vcpu_needs_kick) {
>  			kvm_make_request(KVM_REQ_IRQ_PENDING, target_vcpu);
> @@ -686,7 +687,7 @@ static void vgic_prune_ap_list(struct kvm_vcpu *vcpu)
>  		goto retry;
>  	}
>  
> -	spin_unlock_irqrestore(&vgic_cpu->ap_list_lock, flags);
> +	spin_unlock(&vgic_cpu->ap_list_lock);
>  }
>  
>  static inline void vgic_fold_lr_state(struct kvm_vcpu *vcpu)
> -- 
> 1.8.3.1
> 
Acked-by: Christoffer Dall <christoffer.dall@arm.com>

^ permalink raw reply	[flat|nested] 3+ messages in thread
end of thread, other threads:[~2018-08-06 14:14 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-08-03 13:57 [PATCH 1/2] KVM: arm/arm64: vgic: move DEBUG_SPINLOCK_BUG_ON to vgic.h Jia He
2018-08-03 13:57 ` [PATCH 2/2] KVM: arm/arm64: vgic: no need to call spin_lock_irqsave/restore when irq is disabled Jia He
2018-08-06 14:13   ` Christoffer Dall

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