diff options
Diffstat (limited to 'drivers/perf/arm_pmu_acpi.c')
| -rw-r--r-- | drivers/perf/arm_pmu_acpi.c | 114 |
1 files changed, 67 insertions, 47 deletions
diff --git a/drivers/perf/arm_pmu_acpi.c b/drivers/perf/arm_pmu_acpi.c index 96ffadd654ff..90815ad762eb 100644 --- a/drivers/perf/arm_pmu_acpi.c +++ b/drivers/perf/arm_pmu_acpi.c @@ -13,6 +13,7 @@ #include <linux/percpu.h> #include <linux/perf/arm_pmu.h> +#include <asm/cpu.h> #include <asm/cputype.h> static DEFINE_PER_CPU(struct arm_pmu *, probed_pmus); @@ -187,7 +188,7 @@ out_err: return err; } -static struct arm_pmu *arm_pmu_acpi_find_alloc_pmu(void) +static struct arm_pmu *arm_pmu_acpi_find_pmu(void) { unsigned long cpuid = read_cpuid_id(); struct arm_pmu *pmu; @@ -201,16 +202,7 @@ static struct arm_pmu *arm_pmu_acpi_find_alloc_pmu(void) return pmu; } - pmu = armpmu_alloc_atomic(); - if (!pmu) { - pr_warn("Unable to allocate PMU for CPU%d\n", - smp_processor_id()); - return NULL; - } - - pmu->acpi_cpuid = cpuid; - - return pmu; + return NULL; } /* @@ -242,6 +234,22 @@ static bool pmu_irq_matches(struct arm_pmu *pmu, int irq) return true; } +static void arm_pmu_acpi_associate_pmu_cpu(struct arm_pmu *pmu, + unsigned int cpu) +{ + int irq = per_cpu(pmu_irqs, cpu); + + per_cpu(probed_pmus, cpu) = pmu; + + if (pmu_irq_matches(pmu, irq)) { + struct pmu_hw_events __percpu *hw_events; + hw_events = pmu->hw_events; + per_cpu(hw_events->irq, cpu) = irq; + } + + cpumask_set_cpu(cpu, &pmu->supported_cpus); +} + /* * This must run before the common arm_pmu hotplug logic, so that we can * associate a CPU and its interrupt before the common code tries to manage the @@ -254,42 +262,50 @@ static bool pmu_irq_matches(struct arm_pmu *pmu, int irq) static int arm_pmu_acpi_cpu_starting(unsigned int cpu) { struct arm_pmu *pmu; - struct pmu_hw_events __percpu *hw_events; - int irq; /* If we've already probed this CPU, we have nothing to do */ if (per_cpu(probed_pmus, cpu)) return 0; - irq = per_cpu(pmu_irqs, cpu); - - pmu = arm_pmu_acpi_find_alloc_pmu(); - if (!pmu) - return -ENOMEM; + pmu = arm_pmu_acpi_find_pmu(); + if (!pmu) { + pr_warn_ratelimited("Unable to associate CPU%d with a PMU\n", + cpu); + return 0; + } - per_cpu(probed_pmus, cpu) = pmu; + arm_pmu_acpi_associate_pmu_cpu(pmu, cpu); + return 0; +} - if (pmu_irq_matches(pmu, irq)) { - hw_events = pmu->hw_events; - per_cpu(hw_events->irq, cpu) = irq; - } +static void arm_pmu_acpi_probe_matching_cpus(struct arm_pmu *pmu, + unsigned long cpuid) +{ + int cpu; - cpumask_set_cpu(cpu, &pmu->supported_cpus); + for_each_online_cpu(cpu) { + unsigned long cpu_cpuid = per_cpu(cpu_data, cpu).reg_midr; - /* - * Ideally, we'd probe the PMU here when we find the first matching - * CPU. We can't do that for several reasons; see the comment in - * arm_pmu_acpi_init(). - * - * So for the time being, we're done. - */ - return 0; + if (cpu_cpuid == cpuid) + arm_pmu_acpi_associate_pmu_cpu(pmu, cpu); + } } int arm_pmu_acpi_probe(armpmu_init_fn init_fn) { int pmu_idx = 0; - int cpu, ret; + unsigned int cpu; + int ret; + + ret = arm_pmu_acpi_parse_irqs(); + if (ret) + return ret; + + ret = cpuhp_setup_state_nocalls(CPUHP_AP_PERF_ARM_ACPI_STARTING, + "perf/arm/pmu_acpi:starting", + arm_pmu_acpi_cpu_starting, NULL); + if (ret) + return ret; /* * Initialise and register the set of PMUs which we know about right @@ -304,13 +320,27 @@ int arm_pmu_acpi_probe(armpmu_init_fn init_fn) * For the moment, as with the platform/DT case, we need at least one * of a PMU's CPUs to be online at probe time. */ - for_each_possible_cpu(cpu) { + for_each_online_cpu(cpu) { struct arm_pmu *pmu = per_cpu(probed_pmus, cpu); + unsigned long cpuid; char *base_name; - if (!pmu || pmu->name) + /* If we've already probed this CPU, we have nothing to do */ + if (pmu) continue; + pmu = armpmu_alloc(); + if (!pmu) { + pr_warn("Unable to allocate PMU for CPU%d\n", + cpu); + return -ENOMEM; + } + + cpuid = per_cpu(cpu_data, cpu).reg_midr; + pmu->acpi_cpuid = cpuid; + + arm_pmu_acpi_probe_matching_cpus(pmu, cpuid); + ret = init_fn(pmu); if (ret == -ENODEV) { /* PMU not handled by this driver, or not present */ @@ -335,26 +365,16 @@ int arm_pmu_acpi_probe(armpmu_init_fn init_fn) } } - return 0; + return ret; } static int arm_pmu_acpi_init(void) { - int ret; - if (acpi_disabled) return 0; arm_spe_acpi_register_device(); - ret = arm_pmu_acpi_parse_irqs(); - if (ret) - return ret; - - ret = cpuhp_setup_state(CPUHP_AP_PERF_ARM_ACPI_STARTING, - "perf/arm/pmu_acpi:starting", - arm_pmu_acpi_cpu_starting, NULL); - - return ret; + return 0; } subsys_initcall(arm_pmu_acpi_init) |