diff options
Diffstat (limited to 'arch/arm64/kvm/arch_timer.c')
| -rw-r--r-- | arch/arm64/kvm/arch_timer.c | 151 |
1 files changed, 70 insertions, 81 deletions
diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c index bb24a76b4224..e1af4301b913 100644 --- a/arch/arm64/kvm/arch_timer.c +++ b/arch/arm64/kvm/arch_timer.c @@ -84,14 +84,10 @@ u64 timer_get_cval(struct arch_timer_context *ctxt) static u64 timer_get_offset(struct arch_timer_context *ctxt) { - struct kvm_vcpu *vcpu = ctxt->vcpu; + if (ctxt->offset.vm_offset) + return *ctxt->offset.vm_offset; - switch(arch_timer_ctx_index(ctxt)) { - case TIMER_VTIMER: - return __vcpu_sys_reg(vcpu, CNTVOFF_EL2); - default: - return 0; - } + return 0; } static void timer_set_ctl(struct arch_timer_context *ctxt, u32 ctl) @@ -128,15 +124,12 @@ static void timer_set_cval(struct arch_timer_context *ctxt, u64 cval) static void timer_set_offset(struct arch_timer_context *ctxt, u64 offset) { - struct kvm_vcpu *vcpu = ctxt->vcpu; - - switch(arch_timer_ctx_index(ctxt)) { - case TIMER_VTIMER: - __vcpu_sys_reg(vcpu, CNTVOFF_EL2) = offset; - break; - default: + if (!ctxt->offset.vm_offset) { WARN(offset, "timer %ld\n", arch_timer_ctx_index(ctxt)); + return; } + + WRITE_ONCE(*ctxt->offset.vm_offset, offset); } u64 kvm_phys_timer_read(void) @@ -428,14 +421,17 @@ 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 +455,22 @@ 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 +544,7 @@ 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 +565,6 @@ 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 +639,6 @@ 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 +694,6 @@ 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); } /* @@ -761,25 +758,6 @@ int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu) return 0; } -/* Make the updates of cntvoff for all vtimer contexts atomic */ -static void update_vtimer_cntvoff(struct kvm_vcpu *vcpu, u64 cntvoff) -{ - unsigned long i; - struct kvm *kvm = vcpu->kvm; - struct kvm_vcpu *tmp; - - mutex_lock(&kvm->lock); - kvm_for_each_vcpu(i, tmp, kvm) - timer_set_offset(vcpu_vtimer(tmp), cntvoff); - - /* - * When called from the vcpu create path, the CPU being created is not - * included in the loop above, so we just set it here as well. - */ - timer_set_offset(vcpu_vtimer(vcpu), cntvoff); - mutex_unlock(&kvm->lock); -} - void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu) { struct arch_timer_cpu *timer = vcpu_timer(vcpu); @@ -787,10 +765,11 @@ void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu) struct arch_timer_context *ptimer = vcpu_ptimer(vcpu); vtimer->vcpu = vcpu; + vtimer->offset.vm_offset = &vcpu->kvm->arch.timer_data.voffset; ptimer->vcpu = vcpu; /* Synchronize cntvoff across all vtimers of a VM. */ - update_vtimer_cntvoff(vcpu, kvm_phys_timer_read()); + timer_set_offset(vtimer, kvm_phys_timer_read()); timer_set_offset(ptimer, 0); hrtimer_init(&timer->bg_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD); @@ -811,10 +790,18 @@ 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) @@ -828,7 +815,7 @@ int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, u64 value) break; case KVM_REG_ARM_TIMER_CNT: timer = vcpu_vtimer(vcpu); - update_vtimer_cntvoff(vcpu, kvm_phys_timer_read() - value); + timer_set_offset(timer, kvm_phys_timer_read() - value); break; case KVM_REG_ARM_TIMER_CVAL: timer = vcpu_vtimer(vcpu); @@ -926,14 +913,22 @@ 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 +962,22 @@ 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 +1109,7 @@ 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 +1177,6 @@ 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()); |