From 503d3291a937b726757c1f7c45fa02389d2f4324 Mon Sep 17 00:00:00 2001 From: Zhouyi Zhou Date: Wed, 11 Jun 2014 12:09:03 +0800 Subject: [PATCH] perf/x86/amd: Try to fix some mem allocation failure handling According to Peter's advice, put the failure handling to a goto chain. Compiled in x86_64, could you check if there is anything that I missed. Signed-off-by: Zhouyi Zhou Signed-off-by: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: Linus Torvalds Link: http://lkml.kernel.org/r/1402459743-20513-1-git-send-email-zhouzhouyi@gmail.com Signed-off-by: Ingo Molnar --- arch/x86/kernel/cpu/perf_event_amd_uncore.c | 111 +++++++++++++++----- 1 file changed, 84 insertions(+), 27 deletions(-) diff --git a/arch/x86/kernel/cpu/perf_event_amd_uncore.c b/arch/x86/kernel/cpu/perf_event_amd_uncore.c index 3bbdf4cd38b9..30790d798e6b 100644 --- a/arch/x86/kernel/cpu/perf_event_amd_uncore.c +++ b/arch/x86/kernel/cpu/perf_event_amd_uncore.c @@ -294,31 +294,41 @@ static struct amd_uncore *amd_uncore_alloc(unsigned int cpu) cpu_to_node(cpu)); } -static void amd_uncore_cpu_up_prepare(unsigned int cpu) +static int amd_uncore_cpu_up_prepare(unsigned int cpu) { - struct amd_uncore *uncore; + struct amd_uncore *uncore_nb = NULL, *uncore_l2; if (amd_uncore_nb) { - uncore = amd_uncore_alloc(cpu); - uncore->cpu = cpu; - uncore->num_counters = NUM_COUNTERS_NB; - uncore->rdpmc_base = RDPMC_BASE_NB; - uncore->msr_base = MSR_F15H_NB_PERF_CTL; - uncore->active_mask = &amd_nb_active_mask; - uncore->pmu = &amd_nb_pmu; - *per_cpu_ptr(amd_uncore_nb, cpu) = uncore; + uncore_nb = amd_uncore_alloc(cpu); + if (!uncore_nb) + goto fail; + uncore_nb->cpu = cpu; + uncore_nb->num_counters = NUM_COUNTERS_NB; + uncore_nb->rdpmc_base = RDPMC_BASE_NB; + uncore_nb->msr_base = MSR_F15H_NB_PERF_CTL; + uncore_nb->active_mask = &amd_nb_active_mask; + uncore_nb->pmu = &amd_nb_pmu; + *per_cpu_ptr(amd_uncore_nb, cpu) = uncore_nb; } if (amd_uncore_l2) { - uncore = amd_uncore_alloc(cpu); - uncore->cpu = cpu; - uncore->num_counters = NUM_COUNTERS_L2; - uncore->rdpmc_base = RDPMC_BASE_L2; - uncore->msr_base = MSR_F16H_L2I_PERF_CTL; - uncore->active_mask = &amd_l2_active_mask; - uncore->pmu = &amd_l2_pmu; - *per_cpu_ptr(amd_uncore_l2, cpu) = uncore; + uncore_l2 = amd_uncore_alloc(cpu); + if (!uncore_l2) + goto fail; + uncore_l2->cpu = cpu; + uncore_l2->num_counters = NUM_COUNTERS_L2; + uncore_l2->rdpmc_base = RDPMC_BASE_L2; + uncore_l2->msr_base = MSR_F16H_L2I_PERF_CTL; + uncore_l2->active_mask = &amd_l2_active_mask; + uncore_l2->pmu = &amd_l2_pmu; + *per_cpu_ptr(amd_uncore_l2, cpu) = uncore_l2; } + + return 0; + +fail: + kfree(uncore_nb); + return -ENOMEM; } static struct amd_uncore * @@ -441,7 +451,7 @@ static void uncore_dead(unsigned int cpu, struct amd_uncore * __percpu *uncores) if (!--uncore->refcnt) kfree(uncore); - *per_cpu_ptr(amd_uncore_nb, cpu) = NULL; + *per_cpu_ptr(uncores, cpu) = NULL; } static void amd_uncore_cpu_dead(unsigned int cpu) @@ -461,7 +471,8 @@ amd_uncore_cpu_notifier(struct notifier_block *self, unsigned long action, switch (action & ~CPU_TASKS_FROZEN) { case CPU_UP_PREPARE: - amd_uncore_cpu_up_prepare(cpu); + if (amd_uncore_cpu_up_prepare(cpu)) + return notifier_from_errno(-ENOMEM); break; case CPU_STARTING: @@ -501,20 +512,33 @@ static void __init init_cpu_already_online(void *dummy) amd_uncore_cpu_online(cpu); } +static void cleanup_cpu_online(void *dummy) +{ + unsigned int cpu = smp_processor_id(); + + amd_uncore_cpu_dead(cpu); +} + static int __init amd_uncore_init(void) { - unsigned int cpu; + unsigned int cpu, cpu2; int ret = -ENODEV; if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) - return -ENODEV; + goto fail_nodev; if (!cpu_has_topoext) - return -ENODEV; + goto fail_nodev; if (cpu_has_perfctr_nb) { amd_uncore_nb = alloc_percpu(struct amd_uncore *); - perf_pmu_register(&amd_nb_pmu, amd_nb_pmu.name, -1); + if (!amd_uncore_nb) { + ret = -ENOMEM; + goto fail_nb; + } + ret = perf_pmu_register(&amd_nb_pmu, amd_nb_pmu.name, -1); + if (ret) + goto fail_nb; printk(KERN_INFO "perf: AMD NB counters detected\n"); ret = 0; @@ -522,20 +546,28 @@ static int __init amd_uncore_init(void) if (cpu_has_perfctr_l2) { amd_uncore_l2 = alloc_percpu(struct amd_uncore *); - perf_pmu_register(&amd_l2_pmu, amd_l2_pmu.name, -1); + if (!amd_uncore_l2) { + ret = -ENOMEM; + goto fail_l2; + } + ret = perf_pmu_register(&amd_l2_pmu, amd_l2_pmu.name, -1); + if (ret) + goto fail_l2; printk(KERN_INFO "perf: AMD L2I counters detected\n"); ret = 0; } if (ret) - return -ENODEV; + goto fail_nodev; cpu_notifier_register_begin(); /* init cpus already online before registering for hotplug notifier */ for_each_online_cpu(cpu) { - amd_uncore_cpu_up_prepare(cpu); + ret = amd_uncore_cpu_up_prepare(cpu); + if (ret) + goto fail_online; smp_call_function_single(cpu, init_cpu_already_online, NULL, 1); } @@ -543,5 +575,30 @@ static int __init amd_uncore_init(void) cpu_notifier_register_done(); 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 (cpu_has_perfctr_l2) + perf_pmu_unregister(&amd_l2_pmu); +fail_l2: + if (cpu_has_perfctr_nb) + perf_pmu_unregister(&amd_nb_pmu); + if (amd_uncore_l2) + free_percpu(amd_uncore_l2); +fail_nb: + if (amd_uncore_nb) + free_percpu(amd_uncore_nb); + +fail_nodev: + return ret; } device_initcall(amd_uncore_init);