| Message ID | 20220409184549.1681189-4-oupton@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: arm64: PSCI SYSTEM_SUSPEND support | expand |
Hi Oliver, On Sat, Apr 9, 2022 at 11:46 AM Oliver Upton <oupton@google.com> wrote: > > A subsequent change to KVM will add support for additional power states. > Store the MP state by value rather than keeping track of it as a > boolean. > > No functional change intended. > > Signed-off-by: Oliver Upton <oupton@google.com> > --- > arch/arm64/include/asm/kvm_host.h | 5 +++-- > arch/arm64/kvm/arm.c | 22 ++++++++++++---------- > arch/arm64/kvm/psci.c | 12 ++++++------ > 3 files changed, 21 insertions(+), 18 deletions(-) > > diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h > index 490cd7f3a905..f3f93d48e21a 100644 > --- a/arch/arm64/include/asm/kvm_host.h > +++ b/arch/arm64/include/asm/kvm_host.h > @@ -365,8 +365,8 @@ struct kvm_vcpu_arch { > u32 mdscr_el1; > } guest_debug_preserved; > > - /* vcpu power-off state */ > - bool power_off; > + /* vcpu power state */ > + struct kvm_mp_state mp_state; > > /* Don't run the guest (internal implementation need) */ > bool pause; > @@ -842,5 +842,6 @@ static inline void kvm_hyp_reserve(void) { } > #endif > > void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu); > +bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu); > > #endif /* __ARM64_KVM_HOST_H__ */ > diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c > index 28c83c6ddbae..29e107457c4d 100644 > --- a/arch/arm64/kvm/arm.c > +++ b/arch/arm64/kvm/arm.c > @@ -434,18 +434,20 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) > > void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu) > { > - vcpu->arch.power_off = true; > + vcpu->arch.mp_state.mp_state = KVM_MP_STATE_STOPPED; > kvm_make_request(KVM_REQ_SLEEP, vcpu); > kvm_vcpu_kick(vcpu); > } > > +bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu) > +{ > + return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_STOPPED; > +} > + > int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, > struct kvm_mp_state *mp_state) > { > - if (vcpu->arch.power_off) > - mp_state->mp_state = KVM_MP_STATE_STOPPED; > - else > - mp_state->mp_state = KVM_MP_STATE_RUNNABLE; > + *mp_state = vcpu->arch.mp_state; > > return 0; > } > @@ -457,7 +459,7 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, > > switch (mp_state->mp_state) { > case KVM_MP_STATE_RUNNABLE: > - vcpu->arch.power_off = false; > + vcpu->arch.mp_state = *mp_state; Nit: It might be a bit odd that KVM_MP_STATE_STOPPED case only copies the 'mp_state' field of kvm_mp_state from userspace (that's not a 'copy' operation though), while KVM_MP_STATE_RUNNABLE case copies entire kvm_mp_state from user space. ('mp_state' is the only field of kvm_mp_state though) Reviewed-by: Reiji Watanabe <reijiw@google.com> Thanks, Reiji > break; > case KVM_MP_STATE_STOPPED: > kvm_arm_vcpu_power_off(vcpu); > @@ -480,7 +482,7 @@ int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) > { > bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF); > return ((irq_lines || kvm_vgic_vcpu_pending_irq(v)) > - && !v->arch.power_off && !v->arch.pause); > + && !kvm_arm_vcpu_stopped(v) && !v->arch.pause); > } > > bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) > @@ -597,10 +599,10 @@ static void vcpu_req_sleep(struct kvm_vcpu *vcpu) > struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu); > > rcuwait_wait_event(wait, > - (!vcpu->arch.power_off) &&(!vcpu->arch.pause), > + (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause), > TASK_INTERRUPTIBLE); > > - if (vcpu->arch.power_off || vcpu->arch.pause) { > + if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) { > /* Awaken to handle a signal, request we sleep again later. */ > kvm_make_request(KVM_REQ_SLEEP, vcpu); > } > @@ -1126,7 +1128,7 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, > if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) > kvm_arm_vcpu_power_off(vcpu); > else > - vcpu->arch.power_off = false; > + vcpu->arch.mp_state.mp_state = KVM_MP_STATE_RUNNABLE; > > return 0; > } > diff --git a/arch/arm64/kvm/psci.c b/arch/arm64/kvm/psci.c > index cdc0609c1135..f2f45a3cbe86 100644 > --- a/arch/arm64/kvm/psci.c > +++ b/arch/arm64/kvm/psci.c > @@ -76,7 +76,7 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) > */ > if (!vcpu) > return PSCI_RET_INVALID_PARAMS; > - if (!vcpu->arch.power_off) { > + if (!kvm_arm_vcpu_stopped(vcpu)) { > if (kvm_psci_version(source_vcpu) != KVM_ARM_PSCI_0_1) > return PSCI_RET_ALREADY_ON; > else > @@ -100,12 +100,12 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) > kvm_make_request(KVM_REQ_VCPU_RESET, vcpu); > > /* > - * Make sure the reset request is observed if the change to > - * power_off is observed. > + * Make sure the reset request is observed if the RUNNABLE mp_state is > + * observed. > */ > smp_wmb(); > > - vcpu->arch.power_off = false; > + vcpu->arch.mp_state.mp_state = KVM_MP_STATE_RUNNABLE; > kvm_vcpu_wake_up(vcpu); > > return PSCI_RET_SUCCESS; > @@ -143,7 +143,7 @@ static unsigned long kvm_psci_vcpu_affinity_info(struct kvm_vcpu *vcpu) > mpidr = kvm_vcpu_get_mpidr_aff(tmp); > if ((mpidr & target_affinity_mask) == target_affinity) { > matching_cpus++; > - if (!tmp->arch.power_off) > + if (!kvm_arm_vcpu_stopped(tmp)) > return PSCI_0_2_AFFINITY_LEVEL_ON; > } > } > @@ -169,7 +169,7 @@ static void kvm_prepare_system_event(struct kvm_vcpu *vcpu, u32 type, u64 flags) > * re-initialized. > */ > kvm_for_each_vcpu(i, tmp, vcpu->kvm) > - tmp->arch.power_off = true; > + tmp->arch.mp_state.mp_state = KVM_MP_STATE_STOPPED; > kvm_make_all_cpus_request(vcpu->kvm, KVM_REQ_SLEEP); > > memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event)); > -- > 2.35.1.1178.g4f1659d476-goog >
Hi Reiji, Sorry for the late reply. On Wed, Apr 13, 2022 at 10:26 PM Reiji Watanabe <reijiw@google.com> wrote: [...] > > @@ -457,7 +459,7 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, > > > > switch (mp_state->mp_state) { > > case KVM_MP_STATE_RUNNABLE: > > - vcpu->arch.power_off = false; > > + vcpu->arch.mp_state = *mp_state; > > Nit: It might be a bit odd that KVM_MP_STATE_STOPPED case only copies > the 'mp_state' field of kvm_mp_state from userspace (that's not a 'copy' > operation though), while KVM_MP_STATE_RUNNABLE case copies entire > kvm_mp_state from user space. > ('mp_state' is the only field of kvm_mp_state though) I tried my best to leave this all as-is. I hinted at it in another thread, but I really do think a refactoring would be good to make ARM actually use the mp_state value instead of relying on vCPU requests. I completely agree with the nit, but think it might be better to collapse all of the weirdness around mp_state in a separate patch/series which will drag the vCPU run loop along. > Reviewed-by: Reiji Watanabe <reijiw@google.com> Much appreciated :) -- Best, Oliver
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 490cd7f3a905..f3f93d48e21a 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -365,8 +365,8 @@ struct kvm_vcpu_arch { u32 mdscr_el1; } guest_debug_preserved; - /* vcpu power-off state */ - bool power_off; + /* vcpu power state */ + struct kvm_mp_state mp_state; /* Don't run the guest (internal implementation need) */ bool pause; @@ -842,5 +842,6 @@ static inline void kvm_hyp_reserve(void) { } #endif void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu); +bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu); #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index 28c83c6ddbae..29e107457c4d 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -434,18 +434,20 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu) { - vcpu->arch.power_off = true; + vcpu->arch.mp_state.mp_state = KVM_MP_STATE_STOPPED; kvm_make_request(KVM_REQ_SLEEP, vcpu); kvm_vcpu_kick(vcpu); } +bool kvm_arm_vcpu_stopped(struct kvm_vcpu *vcpu) +{ + return vcpu->arch.mp_state.mp_state == KVM_MP_STATE_STOPPED; +} + int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, struct kvm_mp_state *mp_state) { - if (vcpu->arch.power_off) - mp_state->mp_state = KVM_MP_STATE_STOPPED; - else - mp_state->mp_state = KVM_MP_STATE_RUNNABLE; + *mp_state = vcpu->arch.mp_state; return 0; } @@ -457,7 +459,7 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, switch (mp_state->mp_state) { case KVM_MP_STATE_RUNNABLE: - vcpu->arch.power_off = false; + vcpu->arch.mp_state = *mp_state; break; case KVM_MP_STATE_STOPPED: kvm_arm_vcpu_power_off(vcpu); @@ -480,7 +482,7 @@ int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) { bool irq_lines = *vcpu_hcr(v) & (HCR_VI | HCR_VF); return ((irq_lines || kvm_vgic_vcpu_pending_irq(v)) - && !v->arch.power_off && !v->arch.pause); + && !kvm_arm_vcpu_stopped(v) && !v->arch.pause); } bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) @@ -597,10 +599,10 @@ static void vcpu_req_sleep(struct kvm_vcpu *vcpu) struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu); rcuwait_wait_event(wait, - (!vcpu->arch.power_off) &&(!vcpu->arch.pause), + (!kvm_arm_vcpu_stopped(vcpu)) && (!vcpu->arch.pause), TASK_INTERRUPTIBLE); - if (vcpu->arch.power_off || vcpu->arch.pause) { + if (kvm_arm_vcpu_stopped(vcpu) || vcpu->arch.pause) { /* Awaken to handle a signal, request we sleep again later. */ kvm_make_request(KVM_REQ_SLEEP, vcpu); } @@ -1126,7 +1128,7 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu, if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) kvm_arm_vcpu_power_off(vcpu); else - vcpu->arch.power_off = false; + vcpu->arch.mp_state.mp_state = KVM_MP_STATE_RUNNABLE; return 0; } diff --git a/arch/arm64/kvm/psci.c b/arch/arm64/kvm/psci.c index cdc0609c1135..f2f45a3cbe86 100644 --- a/arch/arm64/kvm/psci.c +++ b/arch/arm64/kvm/psci.c @@ -76,7 +76,7 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) */ if (!vcpu) return PSCI_RET_INVALID_PARAMS; - if (!vcpu->arch.power_off) { + if (!kvm_arm_vcpu_stopped(vcpu)) { if (kvm_psci_version(source_vcpu) != KVM_ARM_PSCI_0_1) return PSCI_RET_ALREADY_ON; else @@ -100,12 +100,12 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) kvm_make_request(KVM_REQ_VCPU_RESET, vcpu); /* - * Make sure the reset request is observed if the change to - * power_off is observed. + * Make sure the reset request is observed if the RUNNABLE mp_state is + * observed. */ smp_wmb(); - vcpu->arch.power_off = false; + vcpu->arch.mp_state.mp_state = KVM_MP_STATE_RUNNABLE; kvm_vcpu_wake_up(vcpu); return PSCI_RET_SUCCESS; @@ -143,7 +143,7 @@ static unsigned long kvm_psci_vcpu_affinity_info(struct kvm_vcpu *vcpu) mpidr = kvm_vcpu_get_mpidr_aff(tmp); if ((mpidr & target_affinity_mask) == target_affinity) { matching_cpus++; - if (!tmp->arch.power_off) + if (!kvm_arm_vcpu_stopped(tmp)) return PSCI_0_2_AFFINITY_LEVEL_ON; } } @@ -169,7 +169,7 @@ static void kvm_prepare_system_event(struct kvm_vcpu *vcpu, u32 type, u64 flags) * re-initialized. */ kvm_for_each_vcpu(i, tmp, vcpu->kvm) - tmp->arch.power_off = true; + tmp->arch.mp_state.mp_state = KVM_MP_STATE_STOPPED; kvm_make_all_cpus_request(vcpu->kvm, KVM_REQ_SLEEP); memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event));
A subsequent change to KVM will add support for additional power states. Store the MP state by value rather than keeping track of it as a boolean. No functional change intended. Signed-off-by: Oliver Upton <oupton@google.com> --- arch/arm64/include/asm/kvm_host.h | 5 +++-- arch/arm64/kvm/arm.c | 22 ++++++++++++---------- arch/arm64/kvm/psci.c | 12 ++++++------ 3 files changed, 21 insertions(+), 18 deletions(-)