From: Thomas Gleixner Install the callback via the state machine and let the core invoke the callbacks on the already online CPUs. Signed-off-by: Thomas Gleixner Reviewed-by: Sebastian Andrzej Siewior Cc: Steven Miao Signed-off-by: Anna-Maria Gleixner --- arch/blackfin/kernel/perf_event.c | 26 +++++--------------------- include/linux/cpuhotplug.h | 1 + 2 files changed, 6 insertions(+), 21 deletions(-) --- a/arch/blackfin/kernel/perf_event.c +++ b/arch/blackfin/kernel/perf_event.c @@ -453,29 +453,13 @@ static struct pmu pmu = { .read = bfin_pmu_read, }; -static void bfin_pmu_setup(int cpu) +static int bfin_pmu_prepare_cpu(unsigned int cpu) { struct cpu_hw_events *cpuhw = &per_cpu(cpu_hw_events, cpu); + bfin_write_PFCTL(0); memset(cpuhw, 0, sizeof(struct cpu_hw_events)); -} - -static int -bfin_pmu_notifier(struct notifier_block *self, unsigned long action, void *hcpu) -{ - unsigned int cpu = (long)hcpu; - - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_UP_PREPARE: - bfin_write_PFCTL(0); - bfin_pmu_setup(cpu); - break; - - default: - break; - } - - return NOTIFY_OK; + return 0; } static int __init bfin_pmu_init(void) @@ -491,8 +475,8 @@ static int __init bfin_pmu_init(void) ret = perf_pmu_register(&pmu, "cpu", PERF_TYPE_RAW); if (!ret) - perf_cpu_notifier(bfin_pmu_notifier); - + cpuhp_setup_state(CPUHP_PERF_BFIN, "PERF_BFIN", + bfin_pmu_prepare_cpu, NULL); return ret; } early_initcall(bfin_pmu_init); --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -9,6 +9,7 @@ enum cpuhp_state { CPUHP_PERF_X86_UNCORE_PREP, CPUHP_PERF_X86_AMD_UNCORE_PREP, CPUHP_PERF_X86_RAPL_PREP, + CPUHP_PERF_BFIN, CPUHP_NOTIFY_PREPARE, CPUHP_BRINGUP_CPU, CPUHP_AP_IDLE_DEAD,