| Message ID | 1450169379-12336-17-git-send-email-zhaoshenglong@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 15/12/15 08:49, Shannon Zhao wrote: > From: Shannon Zhao <shannon.zhao@linaro.org> > > When calling perf_event_create_kernel_counter to create perf_event, > assign a overflow handler. Then when the perf event overflows, set the > corresponding bit of guest PMOVSSET register. If this counter is enabled > and its interrupt is enabled as well, kick the vcpu to sync the > interrupt. > > On VM entry, if there is counter overflowed, inject the interrupt with > the level set to 1. Otherwise, inject the interrupt with the level set > to 0. > > Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org> > --- > arch/arm/kvm/arm.c | 2 ++ > include/kvm/arm_pmu.h | 2 ++ > virt/kvm/arm/pmu.c | 54 ++++++++++++++++++++++++++++++++++++++++++++++++++- > 3 files changed, 57 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c > index e06fd29..cd696ef 100644 > --- a/arch/arm/kvm/arm.c > +++ b/arch/arm/kvm/arm.c > @@ -28,6 +28,7 @@ > #include <linux/sched.h> > #include <linux/kvm.h> > #include <trace/events/kvm.h> > +#include <kvm/arm_pmu.h> > > #define CREATE_TRACE_POINTS > #include "trace.h" > @@ -569,6 +570,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) > * non-preemptible context. > */ > preempt_disable(); > + kvm_pmu_flush_hwstate(vcpu); > kvm_timer_flush_hwstate(vcpu); > kvm_vgic_flush_hwstate(vcpu); > > diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h > index 25b5f98..732ccaf 100644 > --- a/include/kvm/arm_pmu.h > +++ b/include/kvm/arm_pmu.h > @@ -35,6 +35,7 @@ struct kvm_pmu { > struct kvm_pmc pmc[ARMV8_MAX_COUNTERS]; > }; > > +void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu); > u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx); > void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, u64 val); > void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u64 val); > @@ -47,6 +48,7 @@ void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val); > struct kvm_pmu { > }; > > +void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu) {} > u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx) > { > return 0; > diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c > index e664721..eff5b19 100644 > --- a/virt/kvm/arm/pmu.c > +++ b/virt/kvm/arm/pmu.c > @@ -21,6 +21,7 @@ > #include <linux/perf_event.h> > #include <asm/kvm_emulate.h> > #include <kvm/arm_pmu.h> > +#include <kvm/arm_vgic.h> > > /** > * kvm_pmu_get_counter_value - get PMU counter value > @@ -75,6 +76,56 @@ static void kvm_pmu_stop_counter(struct kvm_vcpu *vcpu, struct kvm_pmc *pmc) > } > > /** > + * kvm_pmu_flush_hwstate - flush pmu state to cpu > + * @vcpu: The vcpu pointer > + * > + * Inject virtual PMU IRQ if IRQ is pending for this cpu. > + */ > +void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu) > +{ > + struct kvm_pmu *pmu = &vcpu->arch.pmu; > + u64 overflow; > + > + if (pmu->irq_num == -1) > + return; > + > + if (!(vcpu_sys_reg(vcpu, PMCR_EL0) & ARMV8_PMCR_E)) > + return; > + > + overflow = vcpu_sys_reg(vcpu, PMCNTENSET_EL0) > + & vcpu_sys_reg(vcpu, PMINTENSET_EL1) > + & vcpu_sys_reg(vcpu, PMOVSSET_EL0); You already have something similar to deal with enabling the overflow interrupt. You may want to have a common helper. > + > + kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id, pmu->irq_num, > + overflow ? 1 : 0); nit: can also be written as !!overflow. > +} > + > +static inline struct kvm_vcpu *kvm_pmc_to_vcpu(struct kvm_pmc *pmc) > +{ > + struct kvm_pmu *pmu; > + struct kvm_vcpu_arch *vcpu_arch; > + > + pmc -= pmc->idx; > + pmu = container_of(pmc, struct kvm_pmu, pmc[0]); > + vcpu_arch = container_of(pmu, struct kvm_vcpu_arch, pmu); > + return container_of(vcpu_arch, struct kvm_vcpu, arch); > +} > + > +/** > + * When perf event overflows, call kvm_pmu_overflow_set to set overflow status. > + */ > +static void kvm_pmu_perf_overflow(struct perf_event *perf_event, > + struct perf_sample_data *data, > + struct pt_regs *regs) > +{ > + struct kvm_pmc *pmc = perf_event->overflow_handler_context; > + struct kvm_vcpu *vcpu = kvm_pmc_to_vcpu(pmc); > + int idx = pmc->idx; > + > + kvm_pmu_overflow_set(vcpu, BIT(idx)); > +} > + > +/** > * kvm_pmu_enable_counter - enable selected PMU counter > * @vcpu: The vcpu pointer > * @val: the value guest writes to PMCNTENSET register > @@ -258,7 +309,8 @@ void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data, > /* The initial sample period (overflow count) of an event. */ > attr.sample_period = (-counter) & pmc->bitmask; > > - event = perf_event_create_kernel_counter(&attr, -1, current, NULL, pmc); > + event = perf_event_create_kernel_counter(&attr, -1, current, > + kvm_pmu_perf_overflow, pmc); > if (IS_ERR(event)) { > printk_once("kvm: pmu event creation failed %ld\n", > PTR_ERR(event)); > Thanks, M.
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index e06fd29..cd696ef 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -28,6 +28,7 @@ #include <linux/sched.h> #include <linux/kvm.h> #include <trace/events/kvm.h> +#include <kvm/arm_pmu.h> #define CREATE_TRACE_POINTS #include "trace.h" @@ -569,6 +570,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) * non-preemptible context. */ preempt_disable(); + kvm_pmu_flush_hwstate(vcpu); kvm_timer_flush_hwstate(vcpu); kvm_vgic_flush_hwstate(vcpu); diff --git a/include/kvm/arm_pmu.h b/include/kvm/arm_pmu.h index 25b5f98..732ccaf 100644 --- a/include/kvm/arm_pmu.h +++ b/include/kvm/arm_pmu.h @@ -35,6 +35,7 @@ struct kvm_pmu { struct kvm_pmc pmc[ARMV8_MAX_COUNTERS]; }; +void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu); u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx); void kvm_pmu_disable_counter(struct kvm_vcpu *vcpu, u64 val); void kvm_pmu_enable_counter(struct kvm_vcpu *vcpu, u64 val); @@ -47,6 +48,7 @@ void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val); struct kvm_pmu { }; +void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu) {} u64 kvm_pmu_get_counter_value(struct kvm_vcpu *vcpu, u64 select_idx) { return 0; diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c index e664721..eff5b19 100644 --- a/virt/kvm/arm/pmu.c +++ b/virt/kvm/arm/pmu.c @@ -21,6 +21,7 @@ #include <linux/perf_event.h> #include <asm/kvm_emulate.h> #include <kvm/arm_pmu.h> +#include <kvm/arm_vgic.h> /** * kvm_pmu_get_counter_value - get PMU counter value @@ -75,6 +76,56 @@ static void kvm_pmu_stop_counter(struct kvm_vcpu *vcpu, struct kvm_pmc *pmc) } /** + * kvm_pmu_flush_hwstate - flush pmu state to cpu + * @vcpu: The vcpu pointer + * + * Inject virtual PMU IRQ if IRQ is pending for this cpu. + */ +void kvm_pmu_flush_hwstate(struct kvm_vcpu *vcpu) +{ + struct kvm_pmu *pmu = &vcpu->arch.pmu; + u64 overflow; + + if (pmu->irq_num == -1) + return; + + if (!(vcpu_sys_reg(vcpu, PMCR_EL0) & ARMV8_PMCR_E)) + return; + + overflow = vcpu_sys_reg(vcpu, PMCNTENSET_EL0) + & vcpu_sys_reg(vcpu, PMINTENSET_EL1) + & vcpu_sys_reg(vcpu, PMOVSSET_EL0); + + kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id, pmu->irq_num, + overflow ? 1 : 0); +} + +static inline struct kvm_vcpu *kvm_pmc_to_vcpu(struct kvm_pmc *pmc) +{ + struct kvm_pmu *pmu; + struct kvm_vcpu_arch *vcpu_arch; + + pmc -= pmc->idx; + pmu = container_of(pmc, struct kvm_pmu, pmc[0]); + vcpu_arch = container_of(pmu, struct kvm_vcpu_arch, pmu); + return container_of(vcpu_arch, struct kvm_vcpu, arch); +} + +/** + * When perf event overflows, call kvm_pmu_overflow_set to set overflow status. + */ +static void kvm_pmu_perf_overflow(struct perf_event *perf_event, + struct perf_sample_data *data, + struct pt_regs *regs) +{ + struct kvm_pmc *pmc = perf_event->overflow_handler_context; + struct kvm_vcpu *vcpu = kvm_pmc_to_vcpu(pmc); + int idx = pmc->idx; + + kvm_pmu_overflow_set(vcpu, BIT(idx)); +} + +/** * kvm_pmu_enable_counter - enable selected PMU counter * @vcpu: The vcpu pointer * @val: the value guest writes to PMCNTENSET register @@ -258,7 +309,8 @@ void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data, /* The initial sample period (overflow count) of an event. */ attr.sample_period = (-counter) & pmc->bitmask; - event = perf_event_create_kernel_counter(&attr, -1, current, NULL, pmc); + event = perf_event_create_kernel_counter(&attr, -1, current, + kvm_pmu_perf_overflow, pmc); if (IS_ERR(event)) { printk_once("kvm: pmu event creation failed %ld\n", PTR_ERR(event));