[PATCH v13 7/7] arm: pmu: Add PMU definitions for cores not initially online
From: Jeremy Linton <hidden>
Date: 2017-01-17 20:50:10
Also in:
linux-acpi
Subsystem:
arm pmu profiling and debugging, the rest · Maintainers:
Will Deacon, Mark Rutland, Linus Torvalds
ACPI CPUs aren't associated with a PMU until they have been put online. This means that we potentially have to update a PMU definition the first time a CPU is hot added to the machine. Signed-off-by: Jeremy Linton <redacted> --- drivers/perf/arm_pmu.c | 34 ++++++++++++++++++++++++++++++++-- include/linux/perf/arm_pmu.h | 4 ++++ 2 files changed, 36 insertions(+), 2 deletions(-)
diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index 77ec1ae..cf5122f 100644
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c@@ -711,6 +711,26 @@ static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler) return 0; } +static void arm_perf_associate_new_cpu(struct arm_pmu *lpmu, unsigned int cpu) +{ + struct platform_device *pdev = lpmu->plat_device; + struct resource *res; + struct pmu_hw_events *events; + int num_res; + + for (num_res = 0; num_res < pdev->num_resources; num_res++) { + if (!pdev->resource[num_res].flags) + break; + } + res = &pdev->resource[num_res]; + arm_pmu_acpi_retrieve_irq(res, cpu); + events = per_cpu_ptr(lpmu->hw_events, cpu); + cpumask_set_cpu(cpu, &lpmu->supported_cpus); + if (lpmu->irq_affinity) + lpmu->irq_affinity[num_res] = cpu; + events->percpu_pmu = lpmu; +} + /* * PMU hardware loses all context when a CPU goes offline. * When a CPU is hotplugged back in, since some hardware registers are
@@ -721,10 +741,18 @@ static int arm_perf_starting_cpu(unsigned int cpu, struct hlist_node *node) { struct arm_pmu *pmu = hlist_entry_safe(node, struct arm_pmu, node); - if (!cpumask_test_cpu(cpu, &pmu->supported_cpus)) - return 0; + if (!cpumask_test_cpu(cpu, &pmu->supported_cpus)) { + unsigned int cpuid = read_specific_cpuid(cpu); + + if (acpi_disabled) + return 0; + if (cpuid != pmu->id) + return 0; + arm_perf_associate_new_cpu(pmu, cpu); + } if (pmu->reset) pmu->reset(pmu); + return 0; }
@@ -905,6 +933,8 @@ static int probe_plat_pmu(struct arm_pmu *pmu, struct platform_device *pdev = pmu->plat_device; int irq = platform_get_irq(pdev, 0); + pmu->id = pmuid; + if (irq >= 0 && !irq_is_percpu(irq)) { pmu->irq_affinity = kcalloc(pdev->num_resources, sizeof(int), GFP_KERNEL);
diff --git a/include/linux/perf/arm_pmu.h b/include/linux/perf/arm_pmu.h
index 42b5edb..f652cd1 100644
--- a/include/linux/perf/arm_pmu.h
+++ b/include/linux/perf/arm_pmu.h@@ -112,6 +112,7 @@ struct arm_pmu { struct mutex reserve_mutex; u64 max_period; bool secure_access; /* 32-bit ARM only */ + unsigned int id; #define ARMV8_PMUV3_MAX_COMMON_EVENTS 0x40 DECLARE_BITMAP(pmceid_bitmap, ARMV8_PMUV3_MAX_COMMON_EVENTS); struct platform_device *plat_device;
@@ -168,8 +169,11 @@ int arm_pmu_device_probe(struct platform_device *pdev, #ifdef CONFIG_ARM_PMU_ACPI struct acpi_madt_generic_interrupt; void arm_pmu_parse_acpi(int cpu, struct acpi_madt_generic_interrupt *gic); +int arm_pmu_acpi_retrieve_irq(struct resource *pdev, int cpu); #else #define arm_pmu_parse_acpi(a, b) do { } while (0) +#define arm_pmu_acpi_retrieve_irq(pdev, cpu) \ + do { } while (0) #endif /* CONFIG_ARM_PMU_ACPI */ #endif /* __ARM_PMU_H__ */
--
2.5.5