From c6a84daa3498f269e3b506757506f762b6f56080 Mon Sep 17 00:00:00 2001 From: Anna-Maria Gleixner Date: Wed, 13 Jul 2016 17:16:28 +0000 Subject: [PATCH] perf/x86/amd/power: Convert the hotplug notifier to state machine Install the callbacks via the state machine. Signed-off-by: Anna-Maria Gleixner Cc: Borislav Petkov Cc: Huang Rui Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160713153335.027571056@linutronix.de Signed-off-by: Ingo Molnar --- arch/x86/events/amd/power.c | 58 +++++++------------------------------ include/linux/cpuhotplug.h | 1 + 2 files changed, 12 insertions(+), 47 deletions(-) diff --git a/arch/x86/events/amd/power.c b/arch/x86/events/amd/power.c index 204df18e7cd2..9842270ed2f2 100644 --- a/arch/x86/events/amd/power.c +++ b/arch/x86/events/amd/power.c @@ -228,12 +228,12 @@ static struct pmu pmu_class = { .read = pmu_event_read, }; -static void power_cpu_exit(int cpu) +static int power_cpu_exit(unsigned int cpu) { int target; if (!cpumask_test_and_clear_cpu(cpu, &cpu_mask)) - return; + return 0; /* * Find a new CPU on the same compute unit, if was set in cpumask @@ -245,9 +245,10 @@ static void power_cpu_exit(int cpu) cpumask_set_cpu(target, &cpu_mask); perf_pmu_migrate_context(&pmu_class, cpu, target); } + return 0; } -static void power_cpu_init(int cpu) +static int power_cpu_init(unsigned int cpu) { int target; @@ -263,33 +264,9 @@ static void power_cpu_init(int cpu) target = cpumask_any_but(topology_sibling_cpumask(cpu), cpu); if (target >= nr_cpumask_bits) cpumask_set_cpu(cpu, &cpu_mask); + return 0; } -static int -power_cpu_notifier(struct notifier_block *self, unsigned long action, void *hcpu) -{ - unsigned int cpu = (long)hcpu; - - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_DOWN_FAILED: - case CPU_ONLINE: - power_cpu_init(cpu); - break; - case CPU_DOWN_PREPARE: - power_cpu_exit(cpu); - break; - default: - break; - } - - return NOTIFY_OK; -} - -static struct notifier_block power_cpu_notifier_nb = { - .notifier_call = power_cpu_notifier, - .priority = CPU_PRI_PERF, -}; - static const struct x86_cpu_id cpu_match[] = { { .vendor = X86_VENDOR_AMD, .family = 0x15 }, {}, @@ -297,7 +274,7 @@ static const struct x86_cpu_id cpu_match[] = { static int __init amd_power_pmu_init(void) { - int cpu, target, ret; + int ret; if (!x86_match_cpu(cpu_match)) return 0; @@ -312,38 +289,25 @@ static int __init amd_power_pmu_init(void) return -ENODEV; } - cpu_notifier_register_begin(); - /* Choose one online core of each compute unit. */ - for_each_online_cpu(cpu) { - target = cpumask_first(topology_sibling_cpumask(cpu)); - if (!cpumask_test_cpu(target, &cpu_mask)) - cpumask_set_cpu(target, &cpu_mask); - } + cpuhp_setup_state(CPUHP_AP_PERF_X86_AMD_POWER_ONLINE, + "AP_PERF_X86_AMD_POWER_ONLINE", + power_cpu_init, power_cpu_exit); ret = perf_pmu_register(&pmu_class, "power", -1); if (WARN_ON(ret)) { pr_warn("AMD Power PMU registration failed\n"); - goto out; + return ret; } - __register_cpu_notifier(&power_cpu_notifier_nb); - pr_info("AMD Power PMU detected\n"); - -out: - cpu_notifier_register_done(); - return ret; } module_init(amd_power_pmu_init); static void __exit amd_power_pmu_exit(void) { - cpu_notifier_register_begin(); - __unregister_cpu_notifier(&power_cpu_notifier_nb); - cpu_notifier_register_done(); - + cpuhp_remove_state_nocalls(CPUHP_AP_PERF_X86_AMD_POWER_ONLINE); perf_pmu_unregister(&pmu_class); } module_exit(amd_power_pmu_exit); diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index f187c46eb7a1..acfeda137df8 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -41,6 +41,7 @@ enum cpuhp_state { CPUHP_AP_PERF_X86_ONLINE, CPUHP_AP_PERF_X86_UNCORE_ONLINE, CPUHP_AP_PERF_X86_AMD_UNCORE_ONLINE, + CPUHP_AP_PERF_X86_AMD_POWER_ONLINE, CPUHP_AP_PERF_X86_RAPL_ONLINE, CPUHP_AP_PERF_X86_CQM_ONLINE, CPUHP_AP_PERF_X86_CSTATE_ONLINE,