From: Christoffer Dall <christoffer.dall@xxxxxxx>
The use of a work queue in the hrtimer expire function for the bg_timer
is a leftover from the time when we would inject interrupts when the
bg_timer expired.
Since we are no longer doing that, we can instead call
kvm_vcpu_wake_up() directly from the hrtimer function and remove all
workqueue functionality from the arch timer code.
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Signed-off-by: Christoffer Dall <christoffer.dall@xxxxxxx>
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
---
include/kvm/arm_arch_timer.h | 4 ----
virt/kvm/arm/arch_timer.c | 34 +++++++---------------------------
2 files changed, 7 insertions(+), 31 deletions(-)
diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h
index 6502feb9524b..33771352dcd6 100644
--- a/include/kvm/arm_arch_timer.h
+++ b/include/kvm/arm_arch_timer.h
@@ -21,7 +21,6 @@
#include <linux/clocksource.h>
#include <linux/hrtimer.h>
-#include <linux/workqueue.h>
struct arch_timer_context {
/* Registers: control register, timer value */
@@ -52,9 +51,6 @@ struct arch_timer_cpu {
/* Background timer used when the guest is not running */
struct hrtimer bg_timer;
- /* Work queued with the above timer expires */
- struct work_struct expired;
-
/* Physical timer emulation */
struct hrtimer phys_timer;
diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c
index 17cecc96f735..da261f5e2a91 100644
--- a/virt/kvm/arm/arch_timer.c
+++ b/virt/kvm/arm/arch_timer.c
@@ -70,11 +70,9 @@ static void soft_timer_start(struct hrtimer *hrt, u64 ns)
HRTIMER_MODE_ABS);
}
-static void soft_timer_cancel(struct hrtimer *hrt, struct work_struct *work)
+static void soft_timer_cancel(struct hrtimer *hrt)
{
hrtimer_cancel(hrt);
- if (work)
- cancel_work_sync(work);
}
static irqreturn_t kvm_arch_timer_handler(int irq, void *dev_id)
@@ -102,23 +100,6 @@ static irqreturn_t kvm_arch_timer_handler(int irq, void *dev_id)
return IRQ_HANDLED;
}
-/*
- * Work function for handling the backup timer that we schedule when a vcpu is
- * no longer running, but had a timer programmed to fire in the future.
- */
-static void kvm_timer_inject_irq_work(struct work_struct *work)
-{
- struct kvm_vcpu *vcpu;
-
- vcpu = container_of(work, struct kvm_vcpu, arch.timer_cpu.expired);
-
- /*
- * If the vcpu is blocked we want to wake it up so that it will see
- * the timer has expired when entering the guest.
- */
- kvm_vcpu_wake_up(vcpu);
-}
-
static u64 kvm_timer_compute_delta(struct arch_timer_context *timer_ctx)
{
u64 cval, now;
@@ -188,7 +169,7 @@ static enum hrtimer_restart kvm_bg_timer_expire(struct hrtimer *hrt)
return HRTIMER_RESTART;
}
- schedule_work(&timer->expired);
+ kvm_vcpu_wake_up(vcpu);
return HRTIMER_NORESTART;
}
@@ -300,7 +281,7 @@ static void phys_timer_emulate(struct kvm_vcpu *vcpu)
* then we also don't need a soft timer.
*/
if (kvm_timer_should_fire(ptimer) || !kvm_timer_irq_can_fire(ptimer)) {
- soft_timer_cancel(&timer->phys_timer, NULL);
+ soft_timer_cancel(&timer->phys_timer);
return;
}
@@ -426,7 +407,7 @@ void kvm_timer_unschedule(struct kvm_vcpu *vcpu)
vtimer_restore_state(vcpu);
- soft_timer_cancel(&timer->bg_timer, &timer->expired);
+ soft_timer_cancel(&timer->bg_timer);
}
static void set_cntvoff(u64 cntvoff)
@@ -544,7 +525,7 @@ void kvm_timer_vcpu_put(struct kvm_vcpu *vcpu)
* In any case, we re-schedule the hrtimer for the physical timer when
* coming back to the VCPU thread in kvm_timer_vcpu_load().
*/
- soft_timer_cancel(&timer->phys_timer, NULL);
+ soft_timer_cancel(&timer->phys_timer);
/*
* The kernel may decide to run userspace after calling vcpu_put, so
@@ -637,7 +618,6 @@ void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
update_vtimer_cntvoff(vcpu, kvm_phys_timer_read());
vcpu_ptimer(vcpu)->cntvoff = 0;
- INIT_WORK(&timer->expired, kvm_timer_inject_irq_work);
hrtimer_init(&timer->bg_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
timer->bg_timer.function = kvm_bg_timer_expire;
@@ -794,8 +774,8 @@ void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu)
struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
- soft_timer_cancel(&timer->bg_timer, &timer->expired);
- soft_timer_cancel(&timer->phys_timer, NULL);
+ soft_timer_cancel(&timer->bg_timer);
+ soft_timer_cancel(&timer->phys_timer);
kvm_vgic_unmap_phys_irq(vcpu, vtimer->irq.irq);
}
--
2.19.2
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