From de73708915adc1b3f05e617a86da6b2d68fae141 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Thu, 21 Jun 2018 10:43:59 +0100 Subject: KVM: arm/arm64: Enable adaptative WFE trapping Trapping blocking WFE is extremely beneficial in situations where the system is oversubscribed, as it allows another thread to run while being blocked. In a non-oversubscribed environment, this is the complete opposite, and trapping WFE is just unnecessary overhead. Let's only enable WFE trapping if the CPU has more than a single task to run (that is, more than just the vcpu thread). Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm/include/asm/kvm_emulate.h | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'arch/arm/include/asm/kvm_emulate.h') diff --git a/arch/arm/include/asm/kvm_emulate.h b/arch/arm/include/asm/kvm_emulate.h index 6493bd479ddc..b50fe8380868 100644 --- a/arch/arm/include/asm/kvm_emulate.h +++ b/arch/arm/include/asm/kvm_emulate.h @@ -107,6 +107,16 @@ static inline unsigned long *vcpu_hcr(const struct kvm_vcpu *vcpu) return (unsigned long *)&vcpu->arch.hcr; } +static inline void vcpu_clear_wfe_traps(struct kvm_vcpu *vcpu) +{ + vcpu->arch.hcr &= ~HCR_TWE; +} + +static inline void vcpu_set_wfe_traps(struct kvm_vcpu *vcpu) +{ + vcpu->arch.hcr |= HCR_TWE; +} + static inline bool vcpu_mode_is_32bit(const struct kvm_vcpu *vcpu) { return 1; -- cgit From 062a585ec21ea478be4826be7ddddb5b3ac49789 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Tue, 7 Aug 2018 19:04:40 -0500 Subject: KVM: arm: Use true and false for boolean values Return statements in functions returning bool should use true or false instead of an integer value. This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva Signed-off-by: Marc Zyngier --- arch/arm/include/asm/kvm_emulate.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/arm/include/asm/kvm_emulate.h') diff --git a/arch/arm/include/asm/kvm_emulate.h b/arch/arm/include/asm/kvm_emulate.h index b50fe8380868..2b7eed21b20e 100644 --- a/arch/arm/include/asm/kvm_emulate.h +++ b/arch/arm/include/asm/kvm_emulate.h @@ -119,7 +119,7 @@ static inline void vcpu_set_wfe_traps(struct kvm_vcpu *vcpu) static inline bool vcpu_mode_is_32bit(const struct kvm_vcpu *vcpu) { - return 1; + return true; } static inline unsigned long *vcpu_pc(struct kvm_vcpu *vcpu) -- cgit