| Message ID | 20170923004207.22356-8-cdall@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 23/09/17 01:41, Christoffer Dall wrote: > We are about to add an additional soft timer to the arch timer state for > a VCPU and would like to be able to reuse the functions to program and > cancel a timer, so we make them slightly more generic and rename to make > it more clear that these functions work on soft timers and not the > hardware resource that this code is managing. > > Signed-off-by: Christoffer Dall <cdall@linaro.org> > --- > virt/kvm/arm/arch_timer.c | 33 ++++++++++++++++----------------- > 1 file changed, 16 insertions(+), 17 deletions(-) > > diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c > index 8e89d63..871d8ae 100644 > --- a/virt/kvm/arm/arch_timer.c > +++ b/virt/kvm/arm/arch_timer.c > @@ -56,26 +56,22 @@ u64 kvm_phys_timer_read(void) > return timecounter->cc->read(timecounter->cc); > } > > -static bool timer_is_armed(struct arch_timer_cpu *timer) > +static bool soft_timer_is_armed(struct arch_timer_cpu *timer) > { > return timer->armed; > } > > -/* timer_arm: as in "arm the timer", not as in ARM the company */ > -static void timer_arm(struct arch_timer_cpu *timer, u64 ns) > +static void soft_timer_start(struct hrtimer *hrt, u64 ns) > { > - timer->armed = true; > - hrtimer_start(&timer->timer, ktime_add_ns(ktime_get(), ns), > + hrtimer_start(hrt, ktime_add_ns(ktime_get(), ns), > HRTIMER_MODE_ABS); > } > > -static void timer_disarm(struct arch_timer_cpu *timer) > +static void soft_timer_cancel(struct hrtimer *hrt, struct work_struct *work) > { > - if (timer_is_armed(timer)) { > - hrtimer_cancel(&timer->timer); > - cancel_work_sync(&timer->expired); > - timer->armed = false; > - } > + hrtimer_cancel(hrt); > + if (work) When can this happen? Something in a following patch? > + cancel_work_sync(work); > } > > static irqreturn_t kvm_arch_timer_handler(int irq, void *dev_id) > @@ -271,7 +267,7 @@ static void kvm_timer_emulate(struct kvm_vcpu *vcpu, > return; > > /* The timer has not yet expired, schedule a background timer */ > - timer_arm(timer, kvm_timer_compute_delta(timer_ctx)); > + soft_timer_start(&timer->timer, kvm_timer_compute_delta(timer_ctx)); > } > > /* > @@ -285,7 +281,7 @@ void kvm_timer_schedule(struct kvm_vcpu *vcpu) > struct arch_timer_context *vtimer = vcpu_vtimer(vcpu); > struct arch_timer_context *ptimer = vcpu_ptimer(vcpu); > > - BUG_ON(timer_is_armed(timer)); > + BUG_ON(soft_timer_is_armed(timer)); > > /* > * No need to schedule a background timer if any guest timer has > @@ -306,13 +302,16 @@ void kvm_timer_schedule(struct kvm_vcpu *vcpu) > * The guest timers have not yet expired, schedule a background timer. > * Set the earliest expiration time among the guest timers. > */ > - timer_arm(timer, kvm_timer_earliest_exp(vcpu)); > + timer->armed = true; > + soft_timer_start(&timer->timer, kvm_timer_earliest_exp(vcpu)); > } > > void kvm_timer_unschedule(struct kvm_vcpu *vcpu) > { > struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; > - timer_disarm(timer); > + > + soft_timer_cancel(&timer->timer, &timer->expired); > + timer->armed = false; > } > > static void kvm_timer_flush_hwstate_vgic(struct kvm_vcpu *vcpu) > @@ -448,7 +447,7 @@ void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu) > * This is to cancel the background timer for the physical timer > * emulation if it is set. > */ > - timer_disarm(timer); > + soft_timer_cancel(&timer->timer, &timer->expired); timer_disarm() used to set timer->armed to false, but that's not the case any more. Don't we risk hitting the BUG_ON() in kvm_timer_schedule if we hit WFI? > > /* > * The guest could have modified the timer registers or the timer > @@ -615,7 +614,7 @@ 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); > > - timer_disarm(timer); > + soft_timer_cancel(&timer->timer, &timer->expired); > kvm_vgic_unmap_phys_irq(vcpu, vtimer->irq.irq); > } > > Thanks, M.
diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c index 8e89d63..871d8ae 100644 --- a/virt/kvm/arm/arch_timer.c +++ b/virt/kvm/arm/arch_timer.c @@ -56,26 +56,22 @@ u64 kvm_phys_timer_read(void) return timecounter->cc->read(timecounter->cc); } -static bool timer_is_armed(struct arch_timer_cpu *timer) +static bool soft_timer_is_armed(struct arch_timer_cpu *timer) { return timer->armed; } -/* timer_arm: as in "arm the timer", not as in ARM the company */ -static void timer_arm(struct arch_timer_cpu *timer, u64 ns) +static void soft_timer_start(struct hrtimer *hrt, u64 ns) { - timer->armed = true; - hrtimer_start(&timer->timer, ktime_add_ns(ktime_get(), ns), + hrtimer_start(hrt, ktime_add_ns(ktime_get(), ns), HRTIMER_MODE_ABS); } -static void timer_disarm(struct arch_timer_cpu *timer) +static void soft_timer_cancel(struct hrtimer *hrt, struct work_struct *work) { - if (timer_is_armed(timer)) { - hrtimer_cancel(&timer->timer); - cancel_work_sync(&timer->expired); - timer->armed = false; - } + hrtimer_cancel(hrt); + if (work) + cancel_work_sync(work); } static irqreturn_t kvm_arch_timer_handler(int irq, void *dev_id) @@ -271,7 +267,7 @@ static void kvm_timer_emulate(struct kvm_vcpu *vcpu, return; /* The timer has not yet expired, schedule a background timer */ - timer_arm(timer, kvm_timer_compute_delta(timer_ctx)); + soft_timer_start(&timer->timer, kvm_timer_compute_delta(timer_ctx)); } /* @@ -285,7 +281,7 @@ void kvm_timer_schedule(struct kvm_vcpu *vcpu) struct arch_timer_context *vtimer = vcpu_vtimer(vcpu); struct arch_timer_context *ptimer = vcpu_ptimer(vcpu); - BUG_ON(timer_is_armed(timer)); + BUG_ON(soft_timer_is_armed(timer)); /* * No need to schedule a background timer if any guest timer has @@ -306,13 +302,16 @@ void kvm_timer_schedule(struct kvm_vcpu *vcpu) * The guest timers have not yet expired, schedule a background timer. * Set the earliest expiration time among the guest timers. */ - timer_arm(timer, kvm_timer_earliest_exp(vcpu)); + timer->armed = true; + soft_timer_start(&timer->timer, kvm_timer_earliest_exp(vcpu)); } void kvm_timer_unschedule(struct kvm_vcpu *vcpu) { struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; - timer_disarm(timer); + + soft_timer_cancel(&timer->timer, &timer->expired); + timer->armed = false; } static void kvm_timer_flush_hwstate_vgic(struct kvm_vcpu *vcpu) @@ -448,7 +447,7 @@ void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu) * This is to cancel the background timer for the physical timer * emulation if it is set. */ - timer_disarm(timer); + soft_timer_cancel(&timer->timer, &timer->expired); /* * The guest could have modified the timer registers or the timer @@ -615,7 +614,7 @@ 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); - timer_disarm(timer); + soft_timer_cancel(&timer->timer, &timer->expired); kvm_vgic_unmap_phys_irq(vcpu, vtimer->irq.irq); }
We are about to add an additional soft timer to the arch timer state for a VCPU and would like to be able to reuse the functions to program and cancel a timer, so we make them slightly more generic and rename to make it more clear that these functions work on soft timers and not the hardware resource that this code is managing. Signed-off-by: Christoffer Dall <cdall@linaro.org> --- virt/kvm/arm/arch_timer.c | 33 ++++++++++++++++----------------- 1 file changed, 16 insertions(+), 17 deletions(-)