diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 32b80ecc0ac5886cc4abdba18c126a6e988cc4a0..0aa158657f20cff83270f4251d1294030076c1bb 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -118,6 +118,17 @@ static inline u32 kvm_x2apic_id(struct kvm_lapic *apic)
return apic->vcpu->vcpu_id;
}
+bool kvm_can_post_timer_interrupt(struct kvm_vcpu *vcpu)
+{
+ return pi_inject_timer && kvm_vcpu_apicv_active(vcpu);
+}
+EXPORT_SYMBOL_GPL(kvm_can_post_timer_interrupt);
+
+static bool kvm_use_posted_timer_interrupt(struct kvm_vcpu *vcpu)
+{
+ return kvm_can_post_timer_interrupt(vcpu) && vcpu->mode == IN_GUEST_MODE;
+}
+
static inline bool kvm_apic_map_get_logical_dest(struct kvm_apic_map *map,
u32 dest_id, struct kvm_lapic ***cluster, u16 *mask) {
switch (map->mode) {
@@ -1421,29 +1432,6 @@ static void apic_update_lvtt(struct kvm_lapic *apic)
}
}
-static void apic_timer_expired(struct kvm_lapic *apic)
-{
- struct kvm_vcpu *vcpu = apic->vcpu;
- struct swait_queue_head *q = &vcpu->wq;
- struct kvm_timer *ktimer = &apic->lapic_timer;
-
- if (atomic_read(&apic->lapic_timer.pending))
- return;
-
- atomic_inc(&apic->lapic_timer.pending);
- kvm_set_pending_timer(vcpu);
-
- /*
- * For x86, the atomic_inc() is serialized, thus
- * using swait_active() is safe.
- */
- if (swait_active(q))
- swake_up_one(q);
-
- if (apic_lvtt_tscdeadline(apic) || ktimer->hv_timer_in_use)
- ktimer->expired_tscdeadline = ktimer->tscdeadline;
-}
-
/*
* On APICv, this test will cause a busy wait
* during a higher-priority task.
@@ -1517,7 +1505,7 @@ static inline void adjust_lapic_timer_advance(struct kvm_vcpu *vcpu,
apic->lapic_timer.timer_advance_ns = timer_advance_ns;
}
-void kvm_wait_lapic_expire(struct kvm_vcpu *vcpu)
+static void __kvm_wait_lapic_expire(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic = vcpu->arch.apic;
u64 guest_tsc, tsc_deadline;
@@ -1525,9 +1513,6 @@ void kvm_wait_lapic_expire(struct kvm_vcpu *vcpu)
if (apic->lapic_timer.expired_tscdeadline == 0)
return;
- if (!lapic_timer_int_injected(vcpu))
- return;
-
tsc_deadline = apic->lapic_timer.expired_tscdeadline;
apic->lapic_timer.expired_tscdeadline = 0;
guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
@@ -1539,8 +1524,57 @@ void kvm_wait_lapic_expire(struct kvm_vcpu *vcpu)
if (unlikely(!apic->lapic_timer.timer_advance_adjust_done))
adjust_lapic_timer_advance(vcpu, apic->lapic_timer.advance_expire_delta);
}
+
+void kvm_wait_lapic_expire(struct kvm_vcpu *vcpu)
+{
+ if (lapic_timer_int_injected(vcpu))
+ __kvm_wait_lapic_expire(vcpu);
+}
EXPORT_SYMBOL_GPL(kvm_wait_lapic_expire);
+static void kvm_apic_inject_pending_timer_irqs(struct kvm_lapic *apic)
+{
+ struct kvm_timer *ktimer = &apic->lapic_timer;
+
+ kvm_apic_local_deliver(apic, APIC_LVTT);
+ if (apic_lvtt_tscdeadline(apic))
+ ktimer->tscdeadline = 0;
+ if (apic_lvtt_oneshot(apic)) {
+ ktimer->tscdeadline = 0;
+ ktimer->target_expiration = 0;
+ }
+}
+
+static void apic_timer_expired(struct kvm_lapic *apic)
+{
+ struct kvm_vcpu *vcpu = apic->vcpu;
+ struct swait_queue_head *q = &vcpu->wq;
+ struct kvm_timer *ktimer = &apic->lapic_timer;
+
+ if (atomic_read(&apic->lapic_timer.pending))
+ return;
+
+ if (apic_lvtt_tscdeadline(apic) || ktimer->hv_timer_in_use)
+ ktimer->expired_tscdeadline = ktimer->tscdeadline;
+
+ if (kvm_use_posted_timer_interrupt(apic->vcpu)) {
+ if (apic->lapic_timer.timer_advance_ns)
+ __kvm_wait_lapic_expire(vcpu);
+ kvm_apic_inject_pending_timer_irqs(apic);
+ return;
+ }
+
+ atomic_inc(&apic->lapic_timer.pending);
+ kvm_set_pending_timer(vcpu);
+
+ /*
+ * For x86, the atomic_inc() is serialized, thus
+ * using swait_active() is safe.
+ */
+ if (swait_active(q))
+ swake_up_one(q);
+}
+
static void start_sw_tscdeadline(struct kvm_lapic *apic)
{
struct kvm_timer *ktimer = &apic->lapic_timer;
@@ -2325,13 +2359,7 @@ void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu)
struct kvm_lapic *apic = vcpu->arch.apic;
if (atomic_read(&apic->lapic_timer.pending) > 0) {
- kvm_apic_local_deliver(apic, APIC_LVTT);
- if (apic_lvtt_tscdeadline(apic))
- apic->lapic_timer.tscdeadline = 0;
- if (apic_lvtt_oneshot(apic)) {
- apic->lapic_timer.tscdeadline = 0;
- apic->lapic_timer.target_expiration = 0;
- }
+ kvm_apic_inject_pending_timer_irqs(apic);
atomic_set(&apic->lapic_timer.pending, 0);
}
}
@@ -2453,7 +2481,8 @@ void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu)
{
struct hrtimer *timer;
- if (!lapic_in_kernel(vcpu))
+ if (!lapic_in_kernel(vcpu) ||
+ kvm_can_post_timer_interrupt(vcpu))
return;
timer = &vcpu->arch.apic->lapic_timer.timer;
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index 36747174e4a8ba7b19d5fb58ccfae2974f8e4795..50053d2b8b7bc849b7057406376f874b774c24cd 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -236,6 +236,7 @@ void kvm_lapic_switch_to_hv_timer(struct kvm_vcpu *vcpu);
void kvm_lapic_expired_hv_timer(struct kvm_vcpu *vcpu);
bool kvm_lapic_hv_timer_in_use(struct kvm_vcpu *vcpu);
void kvm_lapic_restart_hv_timer(struct kvm_vcpu *vcpu);
+bool kvm_can_post_timer_interrupt(struct kvm_vcpu *vcpu);
static inline enum lapic_mode kvm_apic_mode(u64 apic_base)
{
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 84f8d49a2fd28eee08538d21f2de567df948f52c..280320f74db7b7ff87f24bb04edd809eb6b4e7eb 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7064,7 +7064,8 @@ static int vmx_set_hv_timer(struct kvm_vcpu *vcpu, u64 guest_deadline_tsc,
u64 tscl, guest_tscl, delta_tsc, lapic_timer_advance_cycles;
struct kvm_timer *ktimer = &vcpu->arch.apic->lapic_timer;
- if (kvm_mwait_in_guest(vcpu->kvm))
+ if (kvm_mwait_in_guest(vcpu->kvm) ||
+ kvm_can_post_timer_interrupt(vcpu))
return -EOPNOTSUPP;
vmx = to_vmx(vcpu);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 6ab30c5e1ae0e9c9a9b83eb69886dcee2396dead..58305cf81182dab02a0a45f5efa85990d2e239b4 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -51,6 +51,7 @@
#include <linux/kvm_irqfd.h>
#include <linux/irqbypass.h>
#include <linux/sched/stat.h>
+#include <linux/sched/isolation.h>
#include <linux/mem_encrypt.h>
#include <trace/events/kvm.h>
@@ -153,6 +154,9 @@ EXPORT_SYMBOL_GPL(enable_vmware_backdoor);
static bool __read_mostly force_emulation_prefix = false;
module_param(force_emulation_prefix, bool, S_IRUGO);
+int __read_mostly pi_inject_timer = -1;
+module_param(pi_inject_timer, bint, S_IRUGO | S_IWUSR);
+
#define KVM_NR_SHARED_MSRS 16
struct kvm_shared_msrs_global {
@@ -7058,6 +7062,8 @@ int kvm_arch_init(void *opaque)
host_xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK);
kvm_lapic_init();
+ if (pi_inject_timer == -1)
+ pi_inject_timer = housekeeping_enabled(HK_FLAG_TIMER);
#ifdef CONFIG_X86_64
pvclock_gtod_register_notifier(&pvclock_gtod_notifier);
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h
index e08a12892e8ba8275addbc9f9d8c98f4fa8051df..6594020c069167f4f889570960698b2d61ba6379 100644
--- a/arch/x86/kvm/x86.h
+++ b/arch/x86/kvm/x86.h
@@ -301,6 +301,8 @@ extern unsigned int min_timer_period_us;
extern bool enable_vmware_backdoor;
+extern int pi_inject_timer;
+
extern struct static_key kvm_no_apic_vcpu;
static inline u64 nsec_to_cycles(struct kvm_vcpu *vcpu, u64 nsec)
diff --git a/include/linux/sched/isolation.h b/include/linux/sched/isolation.h
index b0fb1446fe04d809ab9fa0763e7d7b27ff2a2c6c..6c8512d3be88e4d1d34cbfa861fdbc3094ee925b 100644
--- a/include/linux/sched/isolation.h
+++ b/include/linux/sched/isolation.h
@@ -19,6 +19,7 @@ enum hk_flags {
DECLARE_STATIC_KEY_FALSE(housekeeping_overridden);
extern int housekeeping_any_cpu(enum hk_flags flags);
extern const struct cpumask *housekeeping_cpumask(enum hk_flags flags);
+extern bool housekeeping_enabled(enum hk_flags flags);
extern void housekeeping_affine(struct task_struct *t, enum hk_flags flags);
extern bool housekeeping_test_cpu(int cpu, enum hk_flags flags);
extern void __init housekeeping_init(void);
@@ -35,6 +36,11 @@ static inline const struct cpumask *housekeeping_cpumask(enum hk_flags flags)
return cpu_possible_mask;
}
+static inline bool housekeeping_enabled(enum hk_flags flags)
+{
+ return false;
+}
+
static inline void housekeeping_affine(struct task_struct *t,
enum hk_flags flags) { }
static inline void housekeeping_init(void) { }
diff --git a/kernel/sched/isolation.c b/kernel/sched/isolation.c
index 123ea07a3f3b048089dc1e3e1c6ad8f422ed50ab..ccb28085b11418f539766b96d32901bf05e0a7f6 100644
--- a/kernel/sched/isolation.c
+++ b/kernel/sched/isolation.c
@@ -14,6 +14,12 @@ EXPORT_SYMBOL_GPL(housekeeping_overridden);
static cpumask_var_t housekeeping_mask;
static unsigned int housekeeping_flags;
+bool housekeeping_enabled(enum hk_flags flags)
+{
+ return !!(housekeeping_flags & flags);
+}
+EXPORT_SYMBOL_GPL(housekeeping_enabled);
+
int housekeeping_any_cpu(enum hk_flags flags)
{
if (static_branch_unlikely(&housekeeping_overridden))