From: Sebastian Andrzej Siewior <[email protected]> Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs.
Signed-off-by: Sebastian Andrzej Siewior <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: Chris Zankel <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Max Filippov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: [email protected] Signed-off-by: Anna-Maria Gleixner <[email protected]> --- arch/xtensa/kernel/perf_event.c | 26 +++++++++----------------- include/linux/cpuhotplug.h | 1 + 2 files changed, 10 insertions(+), 17 deletions(-) --- a/arch/xtensa/kernel/perf_event.c +++ b/arch/xtensa/kernel/perf_event.c @@ -404,7 +404,7 @@ static struct pmu xtensa_pmu = { .read = xtensa_pmu_read, }; -static void xtensa_pmu_setup(void) +static int xtensa_pmu_setup(int cpu) { unsigned i; @@ -413,21 +413,7 @@ static void xtensa_pmu_setup(void) set_er(0, XTENSA_PMU_PMCTRL(i)); set_er(get_er(XTENSA_PMU_PMSTAT(i)), XTENSA_PMU_PMSTAT(i)); } -} - -static int xtensa_pmu_notifier(struct notifier_block *self, - unsigned long action, void *data) -{ - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_STARTING: - xtensa_pmu_setup(); - break; - - default: - break; - } - - return NOTIFY_OK; + return 0; } static int __init xtensa_pmu_init(void) @@ -435,7 +421,13 @@ static int __init xtensa_pmu_init(void) int ret; int irq = irq_create_mapping(NULL, XCHAL_PROFILING_INTERRUPT); - perf_cpu_notifier(xtensa_pmu_notifier); + ret = cpuhp_setup_state(CPUHP_AP_PERF_XTENSA_STARTING, + "AP_PERF_XTENSA_STARTING", xtensa_pmu_setup, + NULL); + if (ret) { + pr_err("xtensa_pmu: failed to register CPU-hotplug.\n"); + return ret; + } #if XTENSA_FAKE_NMI enable_irq(irq); #else --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -30,6 +30,7 @@ enum cpuhp_state { CPUHP_AP_PERF_X86_AMD_IBS_STARTING, CPUHP_AP_PERF_X86_CQM_STARTING, CPUHP_AP_PERF_X86_CSTATE_STARTING, + CPUHP_AP_PERF_XTENSA_STARTING, CPUHP_AP_NOTIFY_STARTING, CPUHP_AP_ONLINE, CPUHP_TEARDOWN_CPU,
