[PATCH v7 32/45] arm_pmu: Provide a mechanism for disabling the physical IRQ
From: Steven Price <steven.price@arm.com>
Date: 2025-02-13 16:17:08
Also in:
kvm, kvmarm, linux-coco, lkml
Subsystem:
arm pmu profiling and debugging, the rest · Maintainers:
Will Deacon, Mark Rutland, Linus Torvalds
Arm CCA assigns the physical PMU device to the guest running in realm world, however the IRQs are routed via the host. To enter a realm guest while a PMU IRQ is pending it is necessary to block the physical IRQ to prevent an immediate exit. Provide a mechanism in the PMU driver for KVM to control the physical IRQ. Signed-off-by: Steven Price <steven.price@arm.com> --- v3: Add a dummy function for the !CONFIG_ARM_PMU case. --- drivers/perf/arm_pmu.c | 15 +++++++++++++++ include/linux/perf/arm_pmu.h | 5 +++++ 2 files changed, 20 insertions(+)
diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index 398cce3d76fc..2cdcdda8f638 100644
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c@@ -735,6 +735,21 @@ static int arm_perf_teardown_cpu(unsigned int cpu, struct hlist_node *node) return 0; } +void arm_pmu_set_phys_irq(bool enable) +{ + int cpu = get_cpu(); + struct arm_pmu *pmu = per_cpu(cpu_armpmu, cpu); + int irq; + + irq = armpmu_get_cpu_irq(pmu, cpu); + if (irq && !enable) + per_cpu(cpu_irq_ops, cpu)->disable_pmuirq(irq); + else if (irq && enable) + per_cpu(cpu_irq_ops, cpu)->enable_pmuirq(irq); + + put_cpu(); +} + #ifdef CONFIG_CPU_PM static void cpu_pm_pmu_setup(struct arm_pmu *armpmu, unsigned long cmd) {
diff --git a/include/linux/perf/arm_pmu.h b/include/linux/perf/arm_pmu.h
index 4b5b83677e3f..6c2631e2cbd7 100644
--- a/include/linux/perf/arm_pmu.h
+++ b/include/linux/perf/arm_pmu.h@@ -172,6 +172,7 @@ void kvm_host_pmu_init(struct arm_pmu *pmu); #endif bool arm_pmu_irq_is_nmi(void); +void arm_pmu_set_phys_irq(bool enable); /* Internal functions only for core arm_pmu code */ struct arm_pmu *armpmu_alloc(void);
@@ -182,6 +183,10 @@ void armpmu_free_irq(int irq, int cpu); #define ARMV8_PMU_PDEV_NAME "armv8-pmu" +#else /* CONFIG_ARM_PMU */ + +static inline void arm_pmu_set_phys_irq(bool enable) {} + #endif /* CONFIG_ARM_PMU */ #define ARMV8_SPE_PDEV_NAME "arm,spe-v1"
--
2.43.0