From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Zyngier Subject: [PATCH 29/85] KVM: arm64: Remove noop calls to timer save/restore from VHE switch Date: Wed, 28 Mar 2018 13:51:58 +0100 Message-ID: <20180328125254.31380-30-marc.zyngier@arm.com> References: <20180328125254.31380-1-marc.zyngier@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: Christoffer Dall , Christoffer Dall , Shunyong Yang , Julien Thierry , Andre Przywara , Will Deacon , Shih-Wei Li , Catalin Marinas , Dave Martin To: Paolo Bonzini , =?UTF-8?q?Radim=20Kr=C4=8Dm=C3=A1=C5=99?= , kvmarm@lists.cs.columbia.edu, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org Return-path: In-Reply-To: <20180328125254.31380-1-marc.zyngier@arm.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu List-Id: kvm.vger.kernel.org From: Christoffer Dall The VHE switch function calls __timer_enable_traps and __timer_disable_traps which don't do anything on VHE systems. Therefore, simply remove these calls from the VHE switch function and make the functions non-conditional as they are now only called from the non-VHE switch path. Acked-by: Marc Zyngier Reviewed-by: Andrew Jones Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm64/kvm/hyp/switch.c | 2 -- virt/kvm/arm/hyp/timer-sr.c | 44 ++++++++++++++++++++++---------------------- 2 files changed, 22 insertions(+), 24 deletions(-) diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index 9ffd802e775d..307f8c1fcc2f 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -379,7 +379,6 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) __activate_vm(vcpu->kvm); __vgic_restore_state(vcpu); - __timer_enable_traps(vcpu); /* * We must restore the 32-bit state before the sysregs, thanks @@ -400,7 +399,6 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) __sysreg_save_guest_state(guest_ctxt); __sysreg32_save_state(vcpu); - __timer_disable_traps(vcpu); __vgic_save_state(vcpu); __deactivate_traps(vcpu); diff --git a/virt/kvm/arm/hyp/timer-sr.c b/virt/kvm/arm/hyp/timer-sr.c index f24404b3c8df..77754a62eb0c 100644 --- a/virt/kvm/arm/hyp/timer-sr.c +++ b/virt/kvm/arm/hyp/timer-sr.c @@ -27,34 +27,34 @@ void __hyp_text __kvm_timer_set_cntvoff(u32 cntvoff_low, u32 cntvoff_high) write_sysreg(cntvoff, cntvoff_el2); } +/* + * Should only be called on non-VHE systems. + * VHE systems use EL2 timers and configure EL1 timers in kvm_timer_init_vhe(). + */ void __hyp_text __timer_disable_traps(struct kvm_vcpu *vcpu) { - /* - * We don't need to do this for VHE since the host kernel runs in EL2 - * with HCR_EL2.TGE ==1, which makes those bits have no impact. - */ - if (!has_vhe()) { - u64 val; + u64 val; - /* Allow physical timer/counter access for the host */ - val = read_sysreg(cnthctl_el2); - val |= CNTHCTL_EL1PCTEN | CNTHCTL_EL1PCEN; - write_sysreg(val, cnthctl_el2); - } + /* Allow physical timer/counter access for the host */ + val = read_sysreg(cnthctl_el2); + val |= CNTHCTL_EL1PCTEN | CNTHCTL_EL1PCEN; + write_sysreg(val, cnthctl_el2); } +/* + * Should only be called on non-VHE systems. + * VHE systems use EL2 timers and configure EL1 timers in kvm_timer_init_vhe(). + */ void __hyp_text __timer_enable_traps(struct kvm_vcpu *vcpu) { - if (!has_vhe()) { - u64 val; + u64 val; - /* - * Disallow physical timer access for the guest - * Physical counter access is allowed - */ - val = read_sysreg(cnthctl_el2); - val &= ~CNTHCTL_EL1PCEN; - val |= CNTHCTL_EL1PCTEN; - write_sysreg(val, cnthctl_el2); - } + /* + * Disallow physical timer access for the guest + * Physical counter access is allowed + */ + val = read_sysreg(cnthctl_el2); + val &= ~CNTHCTL_EL1PCEN; + val |= CNTHCTL_EL1PCTEN; + write_sysreg(val, cnthctl_el2); } -- 2.14.2 From mboxrd@z Thu Jan 1 00:00:00 1970 From: marc.zyngier@arm.com (Marc Zyngier) Date: Wed, 28 Mar 2018 13:51:58 +0100 Subject: [PATCH 29/85] KVM: arm64: Remove noop calls to timer save/restore from VHE switch In-Reply-To: <20180328125254.31380-1-marc.zyngier@arm.com> References: <20180328125254.31380-1-marc.zyngier@arm.com> Message-ID: <20180328125254.31380-30-marc.zyngier@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Christoffer Dall The VHE switch function calls __timer_enable_traps and __timer_disable_traps which don't do anything on VHE systems. Therefore, simply remove these calls from the VHE switch function and make the functions non-conditional as they are now only called from the non-VHE switch path. Acked-by: Marc Zyngier Reviewed-by: Andrew Jones Signed-off-by: Christoffer Dall Signed-off-by: Marc Zyngier --- arch/arm64/kvm/hyp/switch.c | 2 -- virt/kvm/arm/hyp/timer-sr.c | 44 ++++++++++++++++++++++---------------------- 2 files changed, 22 insertions(+), 24 deletions(-) diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c index 9ffd802e775d..307f8c1fcc2f 100644 --- a/arch/arm64/kvm/hyp/switch.c +++ b/arch/arm64/kvm/hyp/switch.c @@ -379,7 +379,6 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) __activate_vm(vcpu->kvm); __vgic_restore_state(vcpu); - __timer_enable_traps(vcpu); /* * We must restore the 32-bit state before the sysregs, thanks @@ -400,7 +399,6 @@ int kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) __sysreg_save_guest_state(guest_ctxt); __sysreg32_save_state(vcpu); - __timer_disable_traps(vcpu); __vgic_save_state(vcpu); __deactivate_traps(vcpu); diff --git a/virt/kvm/arm/hyp/timer-sr.c b/virt/kvm/arm/hyp/timer-sr.c index f24404b3c8df..77754a62eb0c 100644 --- a/virt/kvm/arm/hyp/timer-sr.c +++ b/virt/kvm/arm/hyp/timer-sr.c @@ -27,34 +27,34 @@ void __hyp_text __kvm_timer_set_cntvoff(u32 cntvoff_low, u32 cntvoff_high) write_sysreg(cntvoff, cntvoff_el2); } +/* + * Should only be called on non-VHE systems. + * VHE systems use EL2 timers and configure EL1 timers in kvm_timer_init_vhe(). + */ void __hyp_text __timer_disable_traps(struct kvm_vcpu *vcpu) { - /* - * We don't need to do this for VHE since the host kernel runs in EL2 - * with HCR_EL2.TGE ==1, which makes those bits have no impact. - */ - if (!has_vhe()) { - u64 val; + u64 val; - /* Allow physical timer/counter access for the host */ - val = read_sysreg(cnthctl_el2); - val |= CNTHCTL_EL1PCTEN | CNTHCTL_EL1PCEN; - write_sysreg(val, cnthctl_el2); - } + /* Allow physical timer/counter access for the host */ + val = read_sysreg(cnthctl_el2); + val |= CNTHCTL_EL1PCTEN | CNTHCTL_EL1PCEN; + write_sysreg(val, cnthctl_el2); } +/* + * Should only be called on non-VHE systems. + * VHE systems use EL2 timers and configure EL1 timers in kvm_timer_init_vhe(). + */ void __hyp_text __timer_enable_traps(struct kvm_vcpu *vcpu) { - if (!has_vhe()) { - u64 val; + u64 val; - /* - * Disallow physical timer access for the guest - * Physical counter access is allowed - */ - val = read_sysreg(cnthctl_el2); - val &= ~CNTHCTL_EL1PCEN; - val |= CNTHCTL_EL1PCTEN; - write_sysreg(val, cnthctl_el2); - } + /* + * Disallow physical timer access for the guest + * Physical counter access is allowed + */ + val = read_sysreg(cnthctl_el2); + val &= ~CNTHCTL_EL1PCEN; + val |= CNTHCTL_EL1PCTEN; + write_sysreg(val, cnthctl_el2); } -- 2.14.2