kernel/include/kvm/arm_pmu.h, branch linux-5.1.y

KVM: arm/arm64: PMU: Fix overflow interrupt injection

2017-07-25T13:18:01Z

kvm_pmu_overflow_set() is called from perf's interrupt handler, making the call of kvm_vgic_inject_irq() from it introduced with "KVM: arm/arm64: PMU: remove request-less vcpu kick" a really bad idea, as it's quite easy to try and retake a lock that the interrupted context is already holding. The fix is to use a vcpu kick, leaving the interrupt injection to kvm_pmu_sync_hwstate(), like it was doing before the refactoring. We don't just revert, though, because before the kick was request-less, leaving the vcpu exposed to the request-less vcpu kick race, and also because the kick was used unnecessarily from register access handlers. Reviewed-by: Christoffer Dall Signed-off-by: Andrew Jones Signed-off-by: Marc Zyngier

KVM: arm64: Allow creating the PMU without the in-kernel GIC

2017-06-08T14:59:44Z

Since we got support for devices in userspace which allows reporting the PMU overflow output status to userspace, we should actually allow creating the PMU on systems without an in-kernel irqchip, which in turn requires us to slightly clarify error codes for the ABI and move things around for the initialization phase. Signed-off-by: Christoffer Dall Reviewed-by: Marc Zyngier

KVM: arm/arm64: Report PMU overflow interrupts to userspace irqchip

2017-04-09T14:49:39Z

When not using an in-kernel VGIC, but instead emulating an interrupt controller in userspace, we should report the PMU overflow status to that userspace interrupt controller using the KVM_CAP_ARM_USER_IRQ feature. Reviewed-by: Alexander Graf Reviewed-by: Marc Zyngier Signed-off-by: Christoffer Dall

arm64: KVM: fix build with CONFIG_ARM_PMU disabled

2016-06-27T10:55:51Z

When CONFIG_ARM_PMU is disabled, we get the following build error: arch/arm64/kvm/sys_regs.c: In function 'pmu_counter_idx_valid': arch/arm64/kvm/sys_regs.c:564:27: error: 'ARMV8_PMU_CYCLE_IDX' undeclared (first use in this function) if (idx >= val && idx != ARMV8_PMU_CYCLE_IDX) ^ arch/arm64/kvm/sys_regs.c:564:27: note: each undeclared identifier is reported only once for each function it appears in arch/arm64/kvm/sys_regs.c: In function 'access_pmu_evcntr': arch/arm64/kvm/sys_regs.c:592:10: error: 'ARMV8_PMU_CYCLE_IDX' undeclared (first use in this function) idx = ARMV8_PMU_CYCLE_IDX; ^ arch/arm64/kvm/sys_regs.c: In function 'access_pmu_evtyper': arch/arm64/kvm/sys_regs.c:638:14: error: 'ARMV8_PMU_CYCLE_IDX' undeclared (first use in this function) if (idx == ARMV8_PMU_CYCLE_IDX) ^ arch/arm64/kvm/hyp/switch.c:86:15: error: 'ARMV8_PMU_USERENR_MASK' undeclared (first use in this function) write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0); This patch fixes the build with CONFIG_ARM_PMU disabled. Cc: Christoffer Dall Cc: Marc Zyngier Signed-off-by: Sudeep Holla Signed-off-by: Christoffer Dall

arm64: KVM: Add a new vcpu device control group for PMUv3

2016-02-29T18:34:21Z

To configure the virtual PMUv3 overflow interrupt number, we use the vcpu kvm_device ioctl, encapsulating the KVM_ARM_VCPU_PMU_V3_IRQ attribute within the KVM_ARM_VCPU_PMU_V3_CTRL group. After configuring the PMUv3, call the vcpu ioctl with attribute KVM_ARM_VCPU_PMU_V3_INIT to initialize the PMUv3. Signed-off-by: Shannon Zhao Acked-by: Peter Maydell Reviewed-by: Andrew Jones Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier

arm64: KVM: Add a new feature bit for PMUv3

2016-02-29T18:34:21Z

To support guest PMUv3, use one bit of the VCPU INIT feature array. Initialize the PMU when initialzing the vcpu with that bit and PMU overflow interrupt set. Signed-off-by: Shannon Zhao Acked-by: Peter Maydell Reviewed-by: Andrew Jones Signed-off-by: Marc Zyngier

arm64: KVM: Free perf event of PMU when destroying vcpu

2016-02-29T18:34:21Z

When KVM frees VCPU, it needs to free the perf_event of PMU. Signed-off-by: Shannon Zhao Reviewed-by: Marc Zyngier Reviewed-by: Andrew Jones Signed-off-by: Marc Zyngier

arm64: KVM: Reset PMU state when resetting vcpu

2016-02-29T18:34:21Z

When resetting vcpu, it needs to reset the PMU state to initial status. Signed-off-by: Shannon Zhao Reviewed-by: Marc Zyngier Reviewed-by: Andrew Jones Signed-off-by: Marc Zyngier

arm64: KVM: Add PMU overflow interrupt routing

2016-02-29T18:34:21Z

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 and interrupt level is changed, inject the interrupt with corresponding level. On VM exit, sync the interrupt level as well if it has been changed. Signed-off-by: Shannon Zhao Reviewed-by: Marc Zyngier Reviewed-by: Andrew Jones Reviewed-by: Christoffer Dall Signed-off-by: Marc Zyngier

arm64: KVM: Add helper to handle PMCR register bits

2016-02-29T18:34:21Z

According to ARMv8 spec, when writing 1 to PMCR.E, all counters are enabled by PMCNTENSET, while writing 0 to PMCR.E, all counters are disabled. When writing 1 to PMCR.P, reset all event counters, not including PMCCNTR, to zero. When writing 1 to PMCR.C, reset PMCCNTR to zero. Signed-off-by: Shannon Zhao Reviewed-by: Marc Zyngier Signed-off-by: Marc Zyngier