diff mbox series

[v5,22/23] KVM: arm64: GICv4.1: Allow non-trapping WFI when using HW SGIs

Message ID 20200304203330.4967-23-maz@kernel.org (mailing list archive)
State New, archived
Headers show
Series irqchip/gic-v4: GICv4.1 architecture support | expand

Commit Message

Marc Zyngier March 4, 2020, 8:33 p.m. UTC 
Just like for VLPIs, it is beneficial to avoid trapping on WFI when the
vcpu is using the GICv4.1 SGIs.

Add such a check to vcpu_clear_wfx_traps().

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
 arch/arm64/include/asm/kvm_emulate.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

Comments

Zenghui Yu March 20, 2020, 4:23 a.m. UTC | #1 
Hi Marc,

On 2020/3/5 4:33, Marc Zyngier wrote:
> Just like for VLPIs, it is beneficial to avoid trapping on WFI when the
> vcpu is using the GICv4.1 SGIs.
> 
> Add such a check to vcpu_clear_wfx_traps().
> 
> Signed-off-by: Marc Zyngier <maz@kernel.org>

Reviewed-by: Zenghui Yu <yuzenghui@huawei.com>


Thanks

> ---
>   arch/arm64/include/asm/kvm_emulate.h | 3 ++-
>   1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
> index f658dda12364..a30b4eec7cb4 100644
> --- a/arch/arm64/include/asm/kvm_emulate.h
> +++ b/arch/arm64/include/asm/kvm_emulate.h
> @@ -89,7 +89,8 @@ static inline unsigned long *vcpu_hcr(struct kvm_vcpu *vcpu)
>   static inline void vcpu_clear_wfx_traps(struct kvm_vcpu *vcpu)
>   {
>   	vcpu->arch.hcr_el2 &= ~HCR_TWE;
> -	if (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count))
> +	if (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count) ||
> +	    vcpu->kvm->arch.vgic.nassgireq)
>   		vcpu->arch.hcr_el2 &= ~HCR_TWI;
>   	else
>   		vcpu->arch.hcr_el2 |= HCR_TWI;
>
Eric Auger March 20, 2020, 8:12 a.m. UTC | #2 
Hi Marc,

On 3/4/20 9:33 PM, Marc Zyngier wrote:
> Just like for VLPIs, it is beneficial to avoid trapping on WFI when the
> vcpu is using the GICv4.1 SGIs.
> 
> Add such a check to vcpu_clear_wfx_traps().
> 
> Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>

Thanks

Eric
> ---
>  arch/arm64/include/asm/kvm_emulate.h | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
> index f658dda12364..a30b4eec7cb4 100644
> --- a/arch/arm64/include/asm/kvm_emulate.h
> +++ b/arch/arm64/include/asm/kvm_emulate.h
> @@ -89,7 +89,8 @@ static inline unsigned long *vcpu_hcr(struct kvm_vcpu *vcpu)
>  static inline void vcpu_clear_wfx_traps(struct kvm_vcpu *vcpu)
>  {
>  	vcpu->arch.hcr_el2 &= ~HCR_TWE;
> -	if (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count))
> +	if (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count) ||
> +	    vcpu->kvm->arch.vgic.nassgireq)
>  		vcpu->arch.hcr_el2 &= ~HCR_TWI;
>  	else
>  		vcpu->arch.hcr_el2 |= HCR_TWI;
>
diff mbox series

Patch

diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h
index f658dda12364..a30b4eec7cb4 100644
--- a/arch/arm64/include/asm/kvm_emulate.h
+++ b/arch/arm64/include/asm/kvm_emulate.h
@@ -89,7 +89,8 @@  static inline unsigned long *vcpu_hcr(struct kvm_vcpu *vcpu)
 static inline void vcpu_clear_wfx_traps(struct kvm_vcpu *vcpu)
 {
 	vcpu->arch.hcr_el2 &= ~HCR_TWE;
-	if (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count))
+	if (atomic_read(&vcpu->arch.vgic_cpu.vgic_v3.its_vpe.vlpi_count) ||
+	    vcpu->kvm->arch.vgic.nassgireq)
 		vcpu->arch.hcr_el2 &= ~HCR_TWI;
 	else
 		vcpu->arch.hcr_el2 |= HCR_TWI;