[RFC PATCH 1/5] KVM: arm64: Replace power_off with mp_state in struct kvm_vcpu_arch

From: Jean-Philippe Brucker
Date: Tue Jun 08 2021 - 11:55:05 EST


In order to add a new "suspend" power state, replace power_off with
mp_state in struct kvm_vcpu_arch. Factor the vcpu_off() function while
we're here.

No functional change intended.

Signed-off-by: Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx>
---
arch/arm64/include/asm/kvm_host.h | 6 ++++--
arch/arm64/kvm/arm.c | 29 +++++++++++++++--------------
arch/arm64/kvm/psci.c | 19 ++++++-------------
3 files changed, 25 insertions(+), 29 deletions(-)

diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 7cd7d5c8c4bc..55a04f4d5919 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -340,8 +340,8 @@ struct kvm_vcpu_arch {
u32 mdscr_el1;
} guest_debug_preserved;

- /* vcpu power-off state */
- bool power_off;
+ /* vcpu power state (runnable, stopped, halted) */
+ u32 mp_state;

/* Don't run the guest (internal implementation need) */
bool pause;
@@ -720,6 +720,8 @@ int kvm_arm_vcpu_arch_get_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
int kvm_arm_vcpu_arch_has_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
+void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu);
+bool kvm_arm_vcpu_is_off(struct kvm_vcpu *vcpu);

/* Guest/host FPSIMD coordination helpers */
int kvm_arch_vcpu_run_map_fp(struct kvm_vcpu *vcpu);
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index e720148232a0..bcc24adb9c0a 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -435,21 +435,22 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
vcpu->cpu = -1;
}

-static void vcpu_power_off(struct kvm_vcpu *vcpu)
+void kvm_arm_vcpu_power_off(struct kvm_vcpu *vcpu)
{
- vcpu->arch.power_off = true;
+ vcpu->arch.mp_state = KVM_MP_STATE_STOPPED;
kvm_make_request(KVM_REQ_SLEEP, vcpu);
kvm_vcpu_kick(vcpu);
}

+bool kvm_arm_vcpu_is_off(struct kvm_vcpu *vcpu)
+{
+ return vcpu->arch.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->mp_state = vcpu->arch.mp_state;
return 0;
}

@@ -460,10 +461,10 @@ 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 = KVM_MP_STATE_RUNNABLE;
break;
case KVM_MP_STATE_STOPPED:
- vcpu_power_off(vcpu);
+ kvm_arm_vcpu_power_off(vcpu);
break;
default:
ret = -EINVAL;
@@ -483,7 +484,7 @@ 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_is_off(v) && !v->arch.pause);
}

bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
@@ -643,10 +644,10 @@ 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_is_off(vcpu) && !vcpu->arch.pause,
TASK_INTERRUPTIBLE);

- if (vcpu->arch.power_off || vcpu->arch.pause) {
+ if (kvm_arm_vcpu_is_off(vcpu) || vcpu->arch.pause) {
/* Awaken to handle a signal, request we sleep again later. */
kvm_make_request(KVM_REQ_SLEEP, vcpu);
}
@@ -1087,9 +1088,9 @@ static int kvm_arch_vcpu_ioctl_vcpu_init(struct kvm_vcpu *vcpu,
* Handle the "start in power-off" case.
*/
if (test_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features))
- vcpu_power_off(vcpu);
+ kvm_arm_vcpu_power_off(vcpu);
else
- vcpu->arch.power_off = false;
+ vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;

return 0;
}
diff --git a/arch/arm64/kvm/psci.c b/arch/arm64/kvm/psci.c
index db4056ecccfd..24b4a2265dbd 100644
--- a/arch/arm64/kvm/psci.c
+++ b/arch/arm64/kvm/psci.c
@@ -52,13 +52,6 @@ static unsigned long kvm_psci_vcpu_suspend(struct kvm_vcpu *vcpu)
return PSCI_RET_SUCCESS;
}

-static void kvm_psci_vcpu_off(struct kvm_vcpu *vcpu)
-{
- vcpu->arch.power_off = true;
- kvm_make_request(KVM_REQ_SLEEP, vcpu);
- kvm_vcpu_kick(vcpu);
-}
-
static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu)
{
struct vcpu_reset_state *reset_state;
@@ -78,7 +71,7 @@ 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_is_off(vcpu)) {
if (kvm_psci_version(source_vcpu, kvm) != KVM_ARM_PSCI_0_1)
return PSCI_RET_ALREADY_ON;
else
@@ -107,7 +100,7 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu)
*/
smp_wmb();

- vcpu->arch.power_off = false;
+ vcpu->arch.mp_state = KVM_MP_STATE_RUNNABLE;
kvm_vcpu_wake_up(vcpu);

return PSCI_RET_SUCCESS;
@@ -142,7 +135,7 @@ 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_is_off(tmp))
return PSCI_0_2_AFFINITY_LEVEL_ON;
}
}
@@ -168,7 +161,7 @@ static void kvm_prepare_system_event(struct kvm_vcpu *vcpu, u32 type)
* re-initialized.
*/
kvm_for_each_vcpu(i, tmp, vcpu->kvm)
- tmp->arch.power_off = true;
+ tmp->arch.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));
@@ -237,7 +230,7 @@ static int kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
val = kvm_psci_vcpu_suspend(vcpu);
break;
case PSCI_0_2_FN_CPU_OFF:
- kvm_psci_vcpu_off(vcpu);
+ kvm_arm_vcpu_power_off(vcpu);
val = PSCI_RET_SUCCESS;
break;
case PSCI_0_2_FN_CPU_ON:
@@ -350,7 +343,7 @@ static int kvm_psci_0_1_call(struct kvm_vcpu *vcpu)

switch (psci_fn) {
case KVM_PSCI_FN_CPU_OFF:
- kvm_psci_vcpu_off(vcpu);
+ kvm_arm_vcpu_power_off(vcpu);
val = PSCI_RET_SUCCESS;
break;
case KVM_PSCI_FN_CPU_ON:
--
2.31.1