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Diffstat (limited to 'arch/arm64/kvm/arch_timer.c')
-rw-r--r--arch/arm64/kvm/arch_timer.c106
1 files changed, 60 insertions, 46 deletions
diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c
index bb24a76b4224..00610477ec7b 100644
--- a/arch/arm64/kvm/arch_timer.c
+++ b/arch/arm64/kvm/arch_timer.c
@@ -428,14 +428,17 @@ static void timer_emulate(struct arch_timer_context *ctx)
* scheduled for the future. If the timer cannot fire at all,
* then we also don't need a soft timer.
*/
- if (!kvm_timer_irq_can_fire(ctx)) {
- soft_timer_cancel(&ctx->hrtimer);
+ if (should_fire || !kvm_timer_irq_can_fire(ctx))
return;
- }
soft_timer_start(&ctx->hrtimer, kvm_timer_compute_delta(ctx));
}
+static void set_cntvoff(u64 cntvoff)
+{
+ kvm_call_hyp(__kvm_timer_set_cntvoff, cntvoff);
+}
+
static void timer_save_state(struct arch_timer_context *ctx)
{
struct arch_timer_cpu *timer = vcpu_timer(ctx->vcpu);
@@ -459,6 +462,22 @@ static void timer_save_state(struct arch_timer_context *ctx)
write_sysreg_el0(0, SYS_CNTV_CTL);
isb();
+ /*
+ * The kernel may decide to run userspace after
+ * calling vcpu_put, so we reset cntvoff to 0 to
+ * ensure a consistent read between user accesses to
+ * the virtual counter and kernel access to the
+ * physical counter of non-VHE case.
+ *
+ * For VHE, the virtual counter uses a fixed virtual
+ * offset of zero, so no need to zero CNTVOFF_EL2
+ * register, but this is actually useful when switching
+ * between EL1/vEL2 with NV.
+ *
+ * Do it unconditionally, as this is either unavoidable
+ * or dirt cheap.
+ */
+ set_cntvoff(0);
break;
case TIMER_PTIMER:
timer_set_ctl(ctx, read_sysreg_el0(SYS_CNTP_CTL));
@@ -532,6 +551,7 @@ static void timer_restore_state(struct arch_timer_context *ctx)
switch (index) {
case TIMER_VTIMER:
+ set_cntvoff(timer_get_offset(ctx));
write_sysreg_el0(timer_get_cval(ctx), SYS_CNTV_CVAL);
isb();
write_sysreg_el0(timer_get_ctl(ctx), SYS_CNTV_CTL);
@@ -552,11 +572,6 @@ out:
local_irq_restore(flags);
}
-static void set_cntvoff(u64 cntvoff)
-{
- kvm_call_hyp(__kvm_timer_set_cntvoff, cntvoff);
-}
-
static inline void set_timer_irq_phys_active(struct arch_timer_context *ctx, bool active)
{
int r;
@@ -631,8 +646,6 @@ void kvm_timer_vcpu_load(struct kvm_vcpu *vcpu)
kvm_timer_vcpu_load_nogic(vcpu);
}
- set_cntvoff(timer_get_offset(map.direct_vtimer));
-
kvm_timer_unblocking(vcpu);
timer_restore_state(map.direct_vtimer);
@@ -688,15 +701,6 @@ void kvm_timer_vcpu_put(struct kvm_vcpu *vcpu)
if (kvm_vcpu_is_blocking(vcpu))
kvm_timer_blocking(vcpu);
-
- /*
- * The kernel may decide to run userspace after calling vcpu_put, so
- * we reset cntvoff to 0 to ensure a consistent read between user
- * accesses to the virtual counter and kernel access to the physical
- * counter of non-VHE case. For VHE, the virtual counter uses a fixed
- * virtual offset of zero, so no need to zero CNTVOFF_EL2 register.
- */
- set_cntvoff(0);
}
/*
@@ -811,10 +815,18 @@ void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
ptimer->host_timer_irq_flags = host_ptimer_irq_flags;
}
-static void kvm_timer_init_interrupt(void *info)
+void kvm_timer_cpu_up(void)
{
enable_percpu_irq(host_vtimer_irq, host_vtimer_irq_flags);
- enable_percpu_irq(host_ptimer_irq, host_ptimer_irq_flags);
+ if (host_ptimer_irq)
+ enable_percpu_irq(host_ptimer_irq, host_ptimer_irq_flags);
+}
+
+void kvm_timer_cpu_down(void)
+{
+ disable_percpu_irq(host_vtimer_irq);
+ if (host_ptimer_irq)
+ disable_percpu_irq(host_ptimer_irq);
}
int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, u64 value)
@@ -926,14 +938,22 @@ u64 kvm_arm_timer_read_sysreg(struct kvm_vcpu *vcpu,
enum kvm_arch_timers tmr,
enum kvm_arch_timer_regs treg)
{
+ struct arch_timer_context *timer;
+ struct timer_map map;
u64 val;
+ get_timer_map(vcpu, &map);
+ timer = vcpu_get_timer(vcpu, tmr);
+
+ if (timer == map.emul_ptimer)
+ return kvm_arm_timer_read(vcpu, timer, treg);
+
preempt_disable();
- kvm_timer_vcpu_put(vcpu);
+ timer_save_state(timer);
- val = kvm_arm_timer_read(vcpu, vcpu_get_timer(vcpu, tmr), treg);
+ val = kvm_arm_timer_read(vcpu, timer, treg);
- kvm_timer_vcpu_load(vcpu);
+ timer_restore_state(timer);
preempt_enable();
return val;
@@ -967,25 +987,22 @@ void kvm_arm_timer_write_sysreg(struct kvm_vcpu *vcpu,
enum kvm_arch_timer_regs treg,
u64 val)
{
- preempt_disable();
- kvm_timer_vcpu_put(vcpu);
-
- kvm_arm_timer_write(vcpu, vcpu_get_timer(vcpu, tmr), treg, val);
-
- kvm_timer_vcpu_load(vcpu);
- preempt_enable();
-}
-
-static int kvm_timer_starting_cpu(unsigned int cpu)
-{
- kvm_timer_init_interrupt(NULL);
- return 0;
-}
+ struct arch_timer_context *timer;
+ struct timer_map map;
-static int kvm_timer_dying_cpu(unsigned int cpu)
-{
- disable_percpu_irq(host_vtimer_irq);
- return 0;
+ get_timer_map(vcpu, &map);
+ timer = vcpu_get_timer(vcpu, tmr);
+ if (timer == map.emul_ptimer) {
+ soft_timer_cancel(&timer->hrtimer);
+ kvm_arm_timer_write(vcpu, timer, treg, val);
+ timer_emulate(timer);
+ } else {
+ preempt_disable();
+ timer_save_state(timer);
+ kvm_arm_timer_write(vcpu, timer, treg, val);
+ timer_restore_state(timer);
+ preempt_enable();
+ }
}
static int timer_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu)
@@ -1117,7 +1134,7 @@ static int kvm_irq_init(struct arch_timer_kvm_info *info)
return 0;
}
-int kvm_timer_hyp_init(bool has_gic)
+int __init kvm_timer_hyp_init(bool has_gic)
{
struct arch_timer_kvm_info *info;
int err;
@@ -1185,9 +1202,6 @@ int kvm_timer_hyp_init(bool has_gic)
goto out_free_irq;
}
- cpuhp_setup_state(CPUHP_AP_KVM_ARM_TIMER_STARTING,
- "kvm/arm/timer:starting", kvm_timer_starting_cpu,
- kvm_timer_dying_cpu);
return 0;
out_free_irq:
free_percpu_irq(host_vtimer_irq, kvm_get_running_vcpus());