From 6e103c0cfeb9ab8d40822a015da9769595096411 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Wed, 17 Aug 2016 19:14:20 +0200 Subject: arm/perf: Use multi instance instead of custom list Signed-off-by: Sebastian Andrzej Siewior Cc: Peter Zijlstra Cc: Mark Rutland Cc: Will Deacon Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160817171420.sdwk2qivxunzryz4@linutronix.de Signed-off-by: Thomas Gleixner --- drivers/perf/arm_pmu.c | 44 ++++++++++++++++++-------------------------- include/linux/perf/arm_pmu.h | 2 +- 2 files changed, 19 insertions(+), 27 deletions(-) diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c index c494613c1909..b2f742f84111 100644 --- a/drivers/perf/arm_pmu.c +++ b/drivers/perf/arm_pmu.c @@ -688,28 +688,20 @@ static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler) return 0; } -static DEFINE_SPINLOCK(arm_pmu_lock); -static LIST_HEAD(arm_pmu_list); - /* * PMU hardware loses all context when a CPU goes offline. * When a CPU is hotplugged back in, since some hardware registers are * UNKNOWN at reset, the PMU must be explicitly reset to avoid reading * junk values out of them. */ -static int arm_perf_starting_cpu(unsigned int cpu) +static int arm_perf_starting_cpu(unsigned int cpu, struct hlist_node *node) { - struct arm_pmu *pmu; - - spin_lock(&arm_pmu_lock); - list_for_each_entry(pmu, &arm_pmu_list, entry) { + struct arm_pmu *pmu = hlist_entry_safe(node, struct arm_pmu, node); - if (!cpumask_test_cpu(cpu, &pmu->supported_cpus)) - continue; - if (pmu->reset) - pmu->reset(pmu); - } - spin_unlock(&arm_pmu_lock); + if (!cpumask_test_cpu(cpu, &pmu->supported_cpus)) + return 0; + if (pmu->reset) + pmu->reset(pmu); return 0; } @@ -821,9 +813,10 @@ static int cpu_pmu_init(struct arm_pmu *cpu_pmu) if (!cpu_hw_events) return -ENOMEM; - spin_lock(&arm_pmu_lock); - list_add_tail(&cpu_pmu->entry, &arm_pmu_list); - spin_unlock(&arm_pmu_lock); + err = cpuhp_state_add_instance_nocalls(CPUHP_AP_PERF_ARM_STARTING, + &cpu_pmu->node); + if (err) + goto out_free; err = cpu_pm_pmu_register(cpu_pmu); if (err) @@ -859,9 +852,9 @@ static int cpu_pmu_init(struct arm_pmu *cpu_pmu) return 0; out_unregister: - spin_lock(&arm_pmu_lock); - list_del(&cpu_pmu->entry); - spin_unlock(&arm_pmu_lock); + cpuhp_state_remove_instance_nocalls(CPUHP_AP_PERF_ARM_STARTING, + &cpu_pmu->node); +out_free: free_percpu(cpu_hw_events); return err; } @@ -869,9 +862,8 @@ out_unregister: static void cpu_pmu_destroy(struct arm_pmu *cpu_pmu) { cpu_pm_pmu_unregister(cpu_pmu); - spin_lock(&arm_pmu_lock); - list_del(&cpu_pmu->entry); - spin_unlock(&arm_pmu_lock); + cpuhp_state_remove_instance_nocalls(CPUHP_AP_PERF_ARM_STARTING, + &cpu_pmu->node); free_percpu(cpu_pmu->hw_events); } @@ -1068,9 +1060,9 @@ static int arm_pmu_hp_init(void) { int ret; - ret = cpuhp_setup_state_nocalls(CPUHP_AP_PERF_ARM_STARTING, - "AP_PERF_ARM_STARTING", - arm_perf_starting_cpu, NULL); + ret = cpuhp_setup_state_multi(CPUHP_AP_PERF_ARM_STARTING, + "AP_PERF_ARM_STARTING", + arm_perf_starting_cpu, NULL); if (ret) pr_err("CPU hotplug notifier for ARM PMU could not be registered: %d\n", ret); diff --git a/include/linux/perf/arm_pmu.h b/include/linux/perf/arm_pmu.h index e18843809eec..4ad1b408c0bb 100644 --- a/include/linux/perf/arm_pmu.h +++ b/include/linux/perf/arm_pmu.h @@ -109,7 +109,7 @@ struct arm_pmu { DECLARE_BITMAP(pmceid_bitmap, ARMV8_PMUV3_MAX_COMMON_EVENTS); struct platform_device *plat_device; struct pmu_hw_events __percpu *hw_events; - struct list_head entry; + struct hlist_node node; struct notifier_block cpu_pm_nb; }; -- cgit v1.2.3