From 96b2bd3866a0b045330e420a2f1829ff2a3399bc Mon Sep 17 00:00:00 2001 From: Richard Cochran Date: Wed, 13 Jul 2016 17:16:13 +0000 Subject: [PATCH] perf/x86/amd/uncore: Convert to hotplug state machine Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs. Signed-off-by: Richard Cochran Signed-off-by: Anna-Maria Gleixner Reviewed-by: Sebastian Andrzej Siewior Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Borislav Petkov Cc: Chen Yucong Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Thomas Gleixner Cc: Vince Weaver Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160713153333.839150380@linutronix.de Signed-off-by: Ingo Molnar --- arch/x86/events/amd/uncore.c | 122 +++++++++-------------------------- include/linux/cpuhotplug.h | 3 + 2 files changed, 35 insertions(+), 90 deletions(-) diff --git a/arch/x86/events/amd/uncore.c b/arch/x86/events/amd/uncore.c index 98ac57381bf9..e6131d4454e6 100644 --- a/arch/x86/events/amd/uncore.c +++ b/arch/x86/events/amd/uncore.c @@ -358,7 +358,7 @@ amd_uncore_find_online_sibling(struct amd_uncore *this, return this; } -static void amd_uncore_cpu_starting(unsigned int cpu) +static int amd_uncore_cpu_starting(unsigned int cpu) { unsigned int eax, ebx, ecx, edx; struct amd_uncore *uncore; @@ -384,6 +384,8 @@ static void amd_uncore_cpu_starting(unsigned int cpu) uncore = amd_uncore_find_online_sibling(uncore, amd_uncore_l2); *per_cpu_ptr(amd_uncore_l2, cpu) = uncore; } + + return 0; } static void uncore_online(unsigned int cpu, @@ -398,13 +400,15 @@ static void uncore_online(unsigned int cpu, cpumask_set_cpu(cpu, uncore->active_mask); } -static void amd_uncore_cpu_online(unsigned int cpu) +static int amd_uncore_cpu_online(unsigned int cpu) { if (amd_uncore_nb) uncore_online(cpu, amd_uncore_nb); if (amd_uncore_l2) uncore_online(cpu, amd_uncore_l2); + + return 0; } static void uncore_down_prepare(unsigned int cpu, @@ -433,13 +437,15 @@ static void uncore_down_prepare(unsigned int cpu, } } -static void amd_uncore_cpu_down_prepare(unsigned int cpu) +static int amd_uncore_cpu_down_prepare(unsigned int cpu) { if (amd_uncore_nb) uncore_down_prepare(cpu, amd_uncore_nb); if (amd_uncore_l2) uncore_down_prepare(cpu, amd_uncore_l2); + + return 0; } static void uncore_dead(unsigned int cpu, struct amd_uncore * __percpu *uncores) @@ -454,74 +460,19 @@ static void uncore_dead(unsigned int cpu, struct amd_uncore * __percpu *uncores) *per_cpu_ptr(uncores, cpu) = NULL; } -static void amd_uncore_cpu_dead(unsigned int cpu) +static int amd_uncore_cpu_dead(unsigned int cpu) { if (amd_uncore_nb) uncore_dead(cpu, amd_uncore_nb); if (amd_uncore_l2) uncore_dead(cpu, amd_uncore_l2); -} - -static int -amd_uncore_cpu_notifier(struct notifier_block *self, unsigned long action, - void *hcpu) -{ - unsigned int cpu = (long)hcpu; - - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_UP_PREPARE: - if (amd_uncore_cpu_up_prepare(cpu)) - return notifier_from_errno(-ENOMEM); - break; - - case CPU_STARTING: - amd_uncore_cpu_starting(cpu); - break; - - case CPU_ONLINE: - amd_uncore_cpu_online(cpu); - break; - - case CPU_DOWN_PREPARE: - amd_uncore_cpu_down_prepare(cpu); - break; - - case CPU_UP_CANCELED: - case CPU_DEAD: - amd_uncore_cpu_dead(cpu); - break; - - default: - break; - } - - return NOTIFY_OK; -} - -static struct notifier_block amd_uncore_cpu_notifier_block = { - .notifier_call = amd_uncore_cpu_notifier, - .priority = CPU_PRI_PERF + 1, -}; - -static void __init init_cpu_already_online(void *dummy) -{ - unsigned int cpu = smp_processor_id(); - - amd_uncore_cpu_starting(cpu); - amd_uncore_cpu_online(cpu); -} -static void cleanup_cpu_online(void *dummy) -{ - unsigned int cpu = smp_processor_id(); - - amd_uncore_cpu_dead(cpu); + return 0; } static int __init amd_uncore_init(void) { - unsigned int cpu, cpu2; int ret = -ENODEV; if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) @@ -558,38 +509,29 @@ static int __init amd_uncore_init(void) ret = 0; } - if (ret) - goto fail_nodev; - - cpu_notifier_register_begin(); - - /* init cpus already online before registering for hotplug notifier */ - for_each_online_cpu(cpu) { - ret = amd_uncore_cpu_up_prepare(cpu); - if (ret) - goto fail_online; - smp_call_function_single(cpu, init_cpu_already_online, NULL, 1); - } - - __register_cpu_notifier(&amd_uncore_cpu_notifier_block); - cpu_notifier_register_done(); - + /* + * Install callbacks. Core will call them for each online cpu. + */ + if (cpuhp_setup_state(CPUHP_PERF_X86_AMD_UNCORE_PREP, + "PERF_X86_AMD_UNCORE_PREP", + amd_uncore_cpu_up_prepare, amd_uncore_cpu_dead)) + goto fail_l2; + + if (cpuhp_setup_state(CPUHP_AP_PERF_X86_AMD_UNCORE_STARTING, + "AP_PERF_X86_AMD_UNCORE_STARTING", + amd_uncore_cpu_starting, NULL)) + goto fail_prep; + if (cpuhp_setup_state(CPUHP_AP_PERF_X86_AMD_UNCORE_ONLINE, + "AP_PERF_X86_AMD_UNCORE_ONLINE", + amd_uncore_cpu_online, + amd_uncore_cpu_down_prepare)) + goto fail_start; return 0; - -fail_online: - for_each_online_cpu(cpu2) { - if (cpu2 == cpu) - break; - smp_call_function_single(cpu, cleanup_cpu_online, NULL, 1); - } - cpu_notifier_register_done(); - - /* amd_uncore_nb/l2 should have been freed by cleanup_cpu_online */ - amd_uncore_nb = amd_uncore_l2 = NULL; - - if (boot_cpu_has(X86_FEATURE_PERFCTR_L2)) - perf_pmu_unregister(&amd_l2_pmu); +fail_start: + cpuhp_remove_state(CPUHP_AP_PERF_X86_AMD_UNCORE_STARTING); +fail_prep: + cpuhp_remove_state(CPUHP_PERF_X86_AMD_UNCORE_PREP); fail_l2: if (boot_cpu_has(X86_FEATURE_PERFCTR_NB)) perf_pmu_unregister(&amd_nb_pmu); diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 6f91e94c9cc9..569d057cc7d5 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -7,6 +7,7 @@ enum cpuhp_state { CPUHP_PERF_PREPARE, CPUHP_PERF_X86_PREPARE, CPUHP_PERF_X86_UNCORE_PREP, + CPUHP_PERF_X86_AMD_UNCORE_PREP, CPUHP_NOTIFY_PREPARE, CPUHP_BRINGUP_CPU, CPUHP_AP_IDLE_DEAD, @@ -20,6 +21,7 @@ enum cpuhp_state { CPUHP_AP_IRQ_BCM2836_STARTING, CPUHP_AP_ARM_MVEBU_COHERENCY, CPUHP_AP_PERF_X86_UNCORE_STARTING, + CPUHP_AP_PERF_X86_AMD_UNCORE_STARTING, CPUHP_AP_PERF_X86_STARTING, CPUHP_AP_NOTIFY_STARTING, CPUHP_AP_ONLINE, @@ -30,6 +32,7 @@ enum cpuhp_state { CPUHP_AP_PERF_ONLINE, CPUHP_AP_PERF_X86_ONLINE, CPUHP_AP_PERF_X86_UNCORE_ONLINE, + CPUHP_AP_PERF_X86_AMD_UNCORE_ONLINE, CPUHP_AP_NOTIFY_ONLINE, CPUHP_AP_ONLINE_DYN, CPUHP_AP_ONLINE_DYN_END = CPUHP_AP_ONLINE_DYN + 30, -- 2.20.1