diff options
Diffstat (limited to 'arch/arm64/kvm/arch_timer.c')
| -rw-r--r-- | arch/arm64/kvm/arch_timer.c | 77 |
1 files changed, 49 insertions, 28 deletions
diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c index 23346585a294..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); } /* @@ -934,14 +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; @@ -975,13 +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); + struct arch_timer_context *timer; + struct timer_map map; - kvm_timer_vcpu_load(vcpu); - preempt_enable(); + 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) |