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Diffstat (limited to 'arch/x86/kvm/lapic.c')
-rw-r--r--arch/x86/kvm/lapic.c66
1 files changed, 15 insertions, 51 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index afac68c0815..f0b67f2cdd6 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -35,6 +35,12 @@
#include "kvm_cache_regs.h"
#include "irq.h"
+#ifndef CONFIG_X86_64
+#define mod_64(x, y) ((x) - (y) * div64_u64(x, y))
+#else
+#define mod_64(x, y) ((x) % (y))
+#endif
+
#define PRId64 "d"
#define PRIx64 "llx"
#define PRIu64 "u"
@@ -511,52 +517,22 @@ static void apic_send_ipi(struct kvm_lapic *apic)
static u32 apic_get_tmcct(struct kvm_lapic *apic)
{
- u64 counter_passed;
- ktime_t passed, now;
+ ktime_t remaining;
+ s64 ns;
u32 tmcct;
ASSERT(apic != NULL);
- now = apic->timer.dev.base->get_time();
- tmcct = apic_get_reg(apic, APIC_TMICT);
-
/* if initial count is 0, current count should also be 0 */
- if (tmcct == 0)
+ if (apic_get_reg(apic, APIC_TMICT) == 0)
return 0;
- if (unlikely(ktime_to_ns(now) <=
- ktime_to_ns(apic->timer.last_update))) {
- /* Wrap around */
- passed = ktime_add(( {
- (ktime_t) {
- .tv64 = KTIME_MAX -
- (apic->timer.last_update).tv64}; }
- ), now);
- apic_debug("time elapsed\n");
- } else
- passed = ktime_sub(now, apic->timer.last_update);
-
- counter_passed = div64_u64(ktime_to_ns(passed),
- (APIC_BUS_CYCLE_NS * apic->timer.divide_count));
-
- if (counter_passed > tmcct) {
- if (unlikely(!apic_lvtt_period(apic))) {
- /* one-shot timers stick at 0 until reset */
- tmcct = 0;
- } else {
- /*
- * periodic timers reset to APIC_TMICT when they
- * hit 0. The while loop simulates this happening N
- * times. (counter_passed %= tmcct) would also work,
- * but might be slower or not work on 32-bit??
- */
- while (counter_passed > tmcct)
- counter_passed -= tmcct;
- tmcct -= counter_passed;
- }
- } else {
- tmcct -= counter_passed;
- }
+ remaining = hrtimer_expires_remaining(&apic->timer.dev);
+ if (ktime_to_ns(remaining) < 0)
+ remaining = ktime_set(0, 0);
+
+ ns = mod_64(ktime_to_ns(remaining), apic->timer.period);
+ tmcct = div64_u64(ns, (APIC_BUS_CYCLE_NS * apic->timer.divide_count));
return tmcct;
}
@@ -653,8 +629,6 @@ static void start_apic_timer(struct kvm_lapic *apic)
{
ktime_t now = apic->timer.dev.base->get_time();
- apic->timer.last_update = now;
-
apic->timer.period = apic_get_reg(apic, APIC_TMICT) *
APIC_BUS_CYCLE_NS * apic->timer.divide_count;
atomic_set(&apic->timer.pending, 0);
@@ -1110,16 +1084,6 @@ void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu)
}
}
-void kvm_apic_timer_intr_post(struct kvm_vcpu *vcpu, int vec)
-{
- struct kvm_lapic *apic = vcpu->arch.apic;
-
- if (apic && apic_lvt_vector(apic, APIC_LVTT) == vec)
- apic->timer.last_update = ktime_add_ns(
- apic->timer.last_update,
- apic->timer.period);
-}
-
int kvm_get_apic_interrupt(struct kvm_vcpu *vcpu)
{
int vector = kvm_apic_has_interrupt(vcpu);