diff options
| -rw-r--r-- | arch/x86/kvm/lapic.c | 61 | ||||
| -rw-r--r-- | arch/x86/kvm/lapic.h | 7 |
2 files changed, 57 insertions, 11 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 9af25c97612a..38f7dc9c16ee 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1648,13 +1648,18 @@ static void start_sw_tscdeadline(struct kvm_lapic *apic) local_irq_restore(flags); } +static inline u64 tmict_to_ns(struct kvm_lapic *apic, u32 tmict) +{ + return (u64)tmict * APIC_BUS_CYCLE_NS * (u64)apic->divide_count; +} + static void update_target_expiration(struct kvm_lapic *apic, uint32_t old_divisor) { ktime_t now, remaining; u64 ns_remaining_old, ns_remaining_new; - apic->lapic_timer.period = (u64)kvm_lapic_get_reg(apic, APIC_TMICT) - * APIC_BUS_CYCLE_NS * apic->divide_count; + apic->lapic_timer.period = + tmict_to_ns(apic, kvm_lapic_get_reg(apic, APIC_TMICT)); limit_periodic_timer_frequency(apic); now = ktime_get(); @@ -1672,14 +1677,15 @@ static void update_target_expiration(struct kvm_lapic *apic, uint32_t old_diviso apic->lapic_timer.target_expiration = ktime_add_ns(now, ns_remaining_new); } -static bool set_target_expiration(struct kvm_lapic *apic) +static bool set_target_expiration(struct kvm_lapic *apic, u32 count_reg) { ktime_t now; u64 tscl = rdtsc(); + s64 deadline; now = ktime_get(); - apic->lapic_timer.period = (u64)kvm_lapic_get_reg(apic, APIC_TMICT) - * APIC_BUS_CYCLE_NS * apic->divide_count; + apic->lapic_timer.period = + tmict_to_ns(apic, kvm_lapic_get_reg(apic, APIC_TMICT)); if (!apic->lapic_timer.period) { apic->lapic_timer.tscdeadline = 0; @@ -1687,10 +1693,32 @@ static bool set_target_expiration(struct kvm_lapic *apic) } limit_periodic_timer_frequency(apic); + deadline = apic->lapic_timer.period; + + if (apic_lvtt_period(apic) || apic_lvtt_oneshot(apic)) { + if (unlikely(count_reg != APIC_TMICT)) { + deadline = tmict_to_ns(apic, + kvm_lapic_get_reg(apic, count_reg)); + if (unlikely(deadline <= 0)) + deadline = apic->lapic_timer.period; + else if (unlikely(deadline > apic->lapic_timer.period)) { + pr_info_ratelimited( + "kvm: vcpu %i: requested lapic timer restore with " + "starting count register %#x=%u (%lld ns) > initial count (%lld ns). " + "Using initial count to start timer.\n", + apic->vcpu->vcpu_id, + count_reg, + kvm_lapic_get_reg(apic, count_reg), + deadline, apic->lapic_timer.period); + kvm_lapic_set_reg(apic, count_reg, 0); + deadline = apic->lapic_timer.period; + } + } + } apic->lapic_timer.tscdeadline = kvm_read_l1_tsc(apic->vcpu, tscl) + - nsec_to_cycles(apic->vcpu, apic->lapic_timer.period); - apic->lapic_timer.target_expiration = ktime_add_ns(now, apic->lapic_timer.period); + nsec_to_cycles(apic->vcpu, deadline); + apic->lapic_timer.target_expiration = ktime_add_ns(now, deadline); return true; } @@ -1872,17 +1900,22 @@ void kvm_lapic_restart_hv_timer(struct kvm_vcpu *vcpu) restart_apic_timer(apic); } -static void start_apic_timer(struct kvm_lapic *apic) +static void __start_apic_timer(struct kvm_lapic *apic, u32 count_reg) { atomic_set(&apic->lapic_timer.pending, 0); if ((apic_lvtt_period(apic) || apic_lvtt_oneshot(apic)) - && !set_target_expiration(apic)) + && !set_target_expiration(apic, count_reg)) return; restart_apic_timer(apic); } +static void start_apic_timer(struct kvm_lapic *apic) +{ + __start_apic_timer(apic, APIC_TMICT); +} + static void apic_manage_nmi_watchdog(struct kvm_lapic *apic, u32 lvt0_val) { bool lvt0_in_nmi_mode = apic_lvt_nmi_mode(lvt0_val); @@ -2493,6 +2526,14 @@ static int kvm_apic_state_fixup(struct kvm_vcpu *vcpu, int kvm_apic_get_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s) { memcpy(s->regs, vcpu->arch.apic->regs, sizeof(*s)); + + /* + * Get calculated timer current count for remaining timer period (if + * any) and store it in the returned register set. + */ + __kvm_lapic_set_reg(s->regs, APIC_TMCCT, + __apic_read(vcpu->arch.apic, APIC_TMCCT)); + return kvm_apic_state_fixup(vcpu, s, false); } @@ -2520,7 +2561,7 @@ int kvm_apic_set_state(struct kvm_vcpu *vcpu, struct kvm_lapic_state *s) apic_update_lvtt(apic); apic_manage_nmi_watchdog(apic, kvm_lapic_get_reg(apic, APIC_LVT0)); update_divide_count(apic); - start_apic_timer(apic); + __start_apic_timer(apic, APIC_TMCCT); kvm_apic_update_apicv(vcpu); apic->highest_isr_cache = -1; if (vcpu->arch.apicv_active) { diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h index a0ffb4331418..7f15f9e69efe 100644 --- a/arch/x86/kvm/lapic.h +++ b/arch/x86/kvm/lapic.h @@ -161,9 +161,14 @@ static inline u32 kvm_lapic_get_reg(struct kvm_lapic *apic, int reg_off) return *((u32 *) (apic->regs + reg_off)); } +static inline void __kvm_lapic_set_reg(char *regs, int reg_off, u32 val) +{ + *((u32 *) (regs + reg_off)) = val; +} + static inline void kvm_lapic_set_reg(struct kvm_lapic *apic, int reg_off, u32 val) { - *((u32 *) (apic->regs + reg_off)) = val; + __kvm_lapic_set_reg(apic->regs, reg_off, val); } extern struct static_key kvm_no_apic_vcpu; |