| Message ID | 20210804085819.846610-19-oupton@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: Add idempotent controls for migrating system counter state | expand |
On Wed, Aug 04, 2021 at 08:58:16AM +0000, Oliver Upton wrote: > In preparation for emulated physical counter-timer offsetting, configure > traps on every vcpu_load() for VHE systems. As before, these trap > settings do not affect host userspace, and are only active for the > guest. > > Suggested-by: Marc Zyngier <maz@kernel.org> > Signed-off-by: Oliver Upton <oupton@google.com> > --- > arch/arm64/kvm/arch_timer.c | 10 +++++++--- > arch/arm64/kvm/arm.c | 4 +--- > include/kvm/arm_arch_timer.h | 2 -- > 3 files changed, 8 insertions(+), 8 deletions(-) > > diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c > index f15058612994..9ead94aa867d 100644 > --- a/arch/arm64/kvm/arch_timer.c > +++ b/arch/arm64/kvm/arch_timer.c > @@ -51,6 +51,7 @@ static void kvm_arm_timer_write(struct kvm_vcpu *vcpu, > static u64 kvm_arm_timer_read(struct kvm_vcpu *vcpu, > struct arch_timer_context *timer, > enum kvm_arch_timer_regs treg); > +static void kvm_timer_enable_traps_vhe(void); > > u32 timer_get_ctl(struct arch_timer_context *ctxt) > { > @@ -668,6 +669,9 @@ void kvm_timer_vcpu_load(struct kvm_vcpu *vcpu) > > if (map.emul_ptimer) > timer_emulate(map.emul_ptimer); > + > + if (has_vhe()) > + kvm_timer_enable_traps_vhe(); > } > > bool kvm_timer_should_notify_user(struct kvm_vcpu *vcpu) > @@ -1383,12 +1387,12 @@ int kvm_timer_enable(struct kvm_vcpu *vcpu) > } > > /* > - * On VHE system, we only need to configure the EL2 timer trap register once, > - * not for every world switch. > + * On VHE system, we only need to configure the EL2 timer trap register on > + * vcpu_load(), but not every world switch into the guest. > * The host kernel runs at EL2 with HCR_EL2.TGE == 1, > * and this makes those bits have no effect for the host kernel execution. > */ > -void kvm_timer_init_vhe(void) > +static void kvm_timer_enable_traps_vhe(void) > { > /* When HCR_EL2.E2H ==1, EL1PCEN and EL1PCTEN are shifted by 10 */ > u32 cnthctl_shift = 10; > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > index e9a2b8f27792..47ea1e1ba80b 100644 > --- a/arch/arm64/kvm/arm.c > +++ b/arch/arm64/kvm/arm.c > @@ -1558,9 +1558,7 @@ static void cpu_hyp_reinit(void) > > cpu_hyp_reset(); > > - if (is_kernel_in_hyp_mode()) > - kvm_timer_init_vhe(); > - else > + if (!is_kernel_in_hyp_mode()) > cpu_init_hyp_mode(); > > cpu_set_hyp_vector(); > diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h > index 615f9314f6a5..254653b42da0 100644 > --- a/include/kvm/arm_arch_timer.h > +++ b/include/kvm/arm_arch_timer.h > @@ -87,8 +87,6 @@ u64 kvm_phys_timer_read(void); > void kvm_timer_vcpu_load(struct kvm_vcpu *vcpu); > void kvm_timer_vcpu_put(struct kvm_vcpu *vcpu); > > -void kvm_timer_init_vhe(void); > - > bool kvm_arch_timer_get_input_level(int vintid); > > #define vcpu_timer(v) (&(v)->arch.timer_cpu) > -- > 2.32.0.605.g8dce9f2422-goog > Reviewed-by: Andrew Jones <drjones@redhat.com>
diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c index f15058612994..9ead94aa867d 100644 --- a/arch/arm64/kvm/arch_timer.c +++ b/arch/arm64/kvm/arch_timer.c @@ -51,6 +51,7 @@ static void kvm_arm_timer_write(struct kvm_vcpu *vcpu, static u64 kvm_arm_timer_read(struct kvm_vcpu *vcpu, struct arch_timer_context *timer, enum kvm_arch_timer_regs treg); +static void kvm_timer_enable_traps_vhe(void); u32 timer_get_ctl(struct arch_timer_context *ctxt) { @@ -668,6 +669,9 @@ void kvm_timer_vcpu_load(struct kvm_vcpu *vcpu) if (map.emul_ptimer) timer_emulate(map.emul_ptimer); + + if (has_vhe()) + kvm_timer_enable_traps_vhe(); } bool kvm_timer_should_notify_user(struct kvm_vcpu *vcpu) @@ -1383,12 +1387,12 @@ int kvm_timer_enable(struct kvm_vcpu *vcpu) } /* - * On VHE system, we only need to configure the EL2 timer trap register once, - * not for every world switch. + * On VHE system, we only need to configure the EL2 timer trap register on + * vcpu_load(), but not every world switch into the guest. * The host kernel runs at EL2 with HCR_EL2.TGE == 1, * and this makes those bits have no effect for the host kernel execution. */ -void kvm_timer_init_vhe(void) +static void kvm_timer_enable_traps_vhe(void) { /* When HCR_EL2.E2H ==1, EL1PCEN and EL1PCTEN are shifted by 10 */ u32 cnthctl_shift = 10; diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index e9a2b8f27792..47ea1e1ba80b 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -1558,9 +1558,7 @@ static void cpu_hyp_reinit(void) cpu_hyp_reset(); - if (is_kernel_in_hyp_mode()) - kvm_timer_init_vhe(); - else + if (!is_kernel_in_hyp_mode()) cpu_init_hyp_mode(); cpu_set_hyp_vector(); diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h index 615f9314f6a5..254653b42da0 100644 --- a/include/kvm/arm_arch_timer.h +++ b/include/kvm/arm_arch_timer.h @@ -87,8 +87,6 @@ u64 kvm_phys_timer_read(void); void kvm_timer_vcpu_load(struct kvm_vcpu *vcpu); void kvm_timer_vcpu_put(struct kvm_vcpu *vcpu); -void kvm_timer_init_vhe(void); - bool kvm_arch_timer_get_input_level(int vintid); #define vcpu_timer(v) (&(v)->arch.timer_cpu)
In preparation for emulated physical counter-timer offsetting, configure traps on every vcpu_load() for VHE systems. As before, these trap settings do not affect host userspace, and are only active for the guest. Suggested-by: Marc Zyngier <maz@kernel.org> Signed-off-by: Oliver Upton <oupton@google.com> --- arch/arm64/kvm/arch_timer.c | 10 +++++++--- arch/arm64/kvm/arm.c | 4 +--- include/kvm/arm_arch_timer.h | 2 -- 3 files changed, 8 insertions(+), 8 deletions(-)