[PATCH v5 1/4] KVM: LAPIC: Make lapic timer unpinned

From: Wanpeng Li
Date: Fri Jun 21 2019 - 05:42:03 EST


From: Wanpeng Li <wanpengli@xxxxxxxxxxx>

Commit 61abdbe0bcc2 ("kvm: x86: make lapic hrtimer pinned") pinned the
lapic timer to avoid to wait until the next kvm exit for the guest to
see KVM_REQ_PENDING_TIMER set. There is another solution to give a kick
after setting the KVM_REQ_PENDING_TIMER bit, make lapic timer unpinned
will be used in follow up patches.

Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Radim KrÄmÃÅ <rkrcmar@xxxxxxxxxx>
Cc: Marcelo Tosatti <mtosatti@xxxxxxxxxx>
Signed-off-by: Wanpeng Li <wanpengli@xxxxxxxxxxx>
---
arch/x86/kvm/lapic.c | 8 ++++----
arch/x86/kvm/x86.c | 6 +-----
2 files changed, 5 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index e82a18c..87ecb56 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1578,7 +1578,7 @@ static void start_sw_tscdeadline(struct kvm_lapic *apic)
likely(ns > apic->lapic_timer.timer_advance_ns)) {
expire = ktime_add_ns(now, ns);
expire = ktime_sub_ns(expire, ktimer->timer_advance_ns);
- hrtimer_start(&ktimer->timer, expire, HRTIMER_MODE_ABS_PINNED);
+ hrtimer_start(&ktimer->timer, expire, HRTIMER_MODE_ABS);
} else
apic_timer_expired(apic);

@@ -1680,7 +1680,7 @@ static void start_sw_period(struct kvm_lapic *apic)

hrtimer_start(&apic->lapic_timer.timer,
apic->lapic_timer.target_expiration,
- HRTIMER_MODE_ABS_PINNED);
+ HRTIMER_MODE_ABS);
}

bool kvm_lapic_hv_timer_in_use(struct kvm_vcpu *vcpu)
@@ -2317,7 +2317,7 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu, int timer_advance_ns)
apic->vcpu = vcpu;

hrtimer_init(&apic->lapic_timer.timer, CLOCK_MONOTONIC,
- HRTIMER_MODE_ABS_PINNED);
+ HRTIMER_MODE_ABS);
apic->lapic_timer.timer.function = apic_timer_fn;
if (timer_advance_ns == -1) {
apic->lapic_timer.timer_advance_ns = 1000;
@@ -2506,7 +2506,7 @@ void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)

timer = &vcpu->arch.apic->lapic_timer.timer;
if (hrtimer_cancel(timer))
- hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED);
+ hrtimer_start_expires(timer, HRTIMER_MODE_ABS);
}

/*
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index eb5cd25..d7c757d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1437,12 +1437,8 @@ static void update_pvclock_gtod(struct timekeeper *tk)

void kvm_set_pending_timer(struct kvm_vcpu *vcpu)
{
- /*
- * Note: KVM_REQ_PENDING_TIMER is implicitly checked in
- * vcpu_enter_guest. This function is only called from
- * the physical CPU that is running vcpu.
- */
kvm_make_request(KVM_REQ_PENDING_TIMER, vcpu);
+ kvm_vcpu_kick(vcpu);
}

static void kvm_write_wall_clock(struct kvm *kvm, gpa_t wall_clock)
--
2.7.4