[PATCH 5/8] arm: arm64: pmu: Assign platform PMU CPU affinity
From: Jeremy Linton <hidden>
Date: 2016-06-09 22:23:30
Also in:
linux-acpi
Subsystem:
arm pmu profiling and debugging, the rest · Maintainers:
Will Deacon, Mark Rutland, Linus Torvalds
On systems with multiple PMU types the PMU to CPU affinity needs to be detected and set. The CPU to interrupt affinity should also be set. Signed-off-by: Jeremy Linton <redacted> --- drivers/perf/arm_pmu.c | 52 ++++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 42 insertions(+), 10 deletions(-)
diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c
index fee4be0e8..865a9db 100644
--- a/drivers/perf/arm_pmu.c
+++ b/drivers/perf/arm_pmu.c@@ -11,6 +11,7 @@ */ #define pr_fmt(fmt) "hw perfevents: " fmt +#include <linux/acpi.h> #include <linux/bitmap.h> #include <linux/cpumask.h> #include <linux/cpu_pm.h>
@@ -24,6 +25,7 @@ #include <linux/irq.h> #include <linux/irqdesc.h> +#include <asm/cpu.h> #include <asm/cputype.h> #include <asm/irq_regs.h>
@@ -872,25 +874,56 @@ static void cpu_pmu_destroy(struct arm_pmu *cpu_pmu) } /* - * CPU PMU identification and probing. + * CPU PMU identification and probing. Its possible to have + * multiple CPU types in an ARM machine. Assure that we are + * picking the right PMU types based on the CPU in question */ -static int probe_current_pmu(struct arm_pmu *pmu, - const struct pmu_probe_info *info) +static int probe_plat_pmu(struct arm_pmu *pmu, + const struct pmu_probe_info *info, + unsigned int pmuid) { - int cpu = get_cpu(); - unsigned int cpuid = read_cpuid_id(); int ret = -ENODEV; + int cpu; + int aff_ctr = 0; + struct platform_device *pdev = pmu->plat_device; + int irq = platform_get_irq(pdev, 0); - pr_info("probing PMU on CPU %d\n", cpu); + if (irq >= 0 && !irq_is_percpu(irq)) { + pmu->irq_affinity = kcalloc(pdev->num_resources, sizeof(int), + GFP_KERNEL); + if (!pmu->irq_affinity) + return -ENOMEM; + } + + for_each_possible_cpu(cpu) { + unsigned int cpuid = read_specific_cpuid(cpu); + + if (cpuid == pmuid) { + cpumask_set_cpu(cpu, &pmu->supported_cpus); + pr_devel("enable pmu on cpu %d\n", cpu); + if (pmu->irq_affinity) { + pmu->irq_affinity[aff_ctr] = cpu; + aff_ctr++; + } + } + } + pr_debug("probing PMU %X\n", pmuid); + /* find the type of PMU given the CPU */ for (; info->init != NULL; info++) { - if ((cpuid & info->mask) != info->cpuid) + if ((pmuid & info->mask) != info->cpuid) continue; + pr_devel("Found PMU\n"); ret = info->init(pmu); + if (!info->cpuid) { + pmu->name = kasprintf(GFP_KERNEL, "%s_0x%x", + pmu->name, ARM_PARTNUM(pmuid)); + if (!pmu->name) + return -ENOMEM; + } break; } - put_cpu(); return ret; }
@@ -1016,8 +1049,7 @@ int arm_pmu_device_probe(struct platform_device *pdev, if (!ret) ret = init_fn(pmu); } else { - cpumask_setall(&pmu->supported_cpus); - ret = probe_current_pmu(pmu, probe_table); + ret = probe_plat_pmu(pmu, probe_table, read_cpuid_id()); } if (ret) {
--
2.5.5