From: Richard Cochran Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs. Signed-off-by: Richard Cochran Reviewed-by: Sebastian Andrzej Siewior Cc: Daniel Lezcano Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Anna-Maria Gleixner --- drivers/clocksource/qcom-timer.c | 41 +++++++++++----------------------------- include/linux/cpuhotplug.h | 1 + 2 files changed, 12 insertions(+), 30 deletions(-) diff --git a/drivers/clocksource/qcom-timer.c b/drivers/clocksource/qcom-timer.c index 6625763..3283cfa 100644 --- a/drivers/clocksource/qcom-timer.c +++ b/drivers/clocksource/qcom-timer.c @@ -105,9 +105,9 @@ static struct clocksource msm_clocksource = { static int msm_timer_irq; static int msm_timer_has_ppi; -static int msm_local_timer_setup(struct clock_event_device *evt) +static int msm_local_timer_starting_cpu(unsigned int cpu) { - int cpu = smp_processor_id(); + struct clock_event_device *evt = per_cpu_ptr(msm_evt, cpu); int err; evt->irq = msm_timer_irq; @@ -135,35 +135,15 @@ static int msm_local_timer_setup(struct clock_event_device *evt) return 0; } -static void msm_local_timer_stop(struct clock_event_device *evt) +static int msm_local_timer_dying_cpu(unsigned int cpu) { + struct clock_event_device *evt = per_cpu_ptr(msm_evt, cpu); + evt->set_state_shutdown(evt); disable_percpu_irq(evt->irq); + return 0; } -static int msm_timer_cpu_notify(struct notifier_block *self, - unsigned long action, void *hcpu) -{ - /* - * Grab cpu pointer in each case to avoid spurious - * preemptible warnings - */ - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_STARTING: - msm_local_timer_setup(this_cpu_ptr(msm_evt)); - break; - case CPU_DYING: - msm_local_timer_stop(this_cpu_ptr(msm_evt)); - break; - } - - return NOTIFY_OK; -} - -static struct notifier_block msm_timer_cpu_nb = { - .notifier_call = msm_timer_cpu_notify, -}; - static u64 notrace msm_sched_clock_read(void) { return msm_clocksource.read(&msm_clocksource); @@ -200,14 +180,15 @@ static int __init msm_timer_init(u32 dgt_hz, int sched_bits, int irq, if (res) { pr_err("request_percpu_irq failed\n"); } else { - res = register_cpu_notifier(&msm_timer_cpu_nb); + /* Install and invoke hotplug callbacks */ + res = cpuhp_setup_state(CPUHP_AP_QCOM_TIMER_STARTING, + "AP_QCOM_TIMER_STARTING", + msm_local_timer_starting_cpu, + msm_local_timer_dying_cpu); if (res) { free_percpu_irq(irq, msm_evt); goto err; } - - /* Immediately configure the timer on the boot CPU */ - msm_local_timer_setup(raw_cpu_ptr(msm_evt)); } err: diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 2d20836..5121ec1 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -40,6 +40,7 @@ enum cpuhp_state { CPUHP_AP_ARM_ARCH_TIMER_STARTING, CPUHP_AP_DUMMY_TIMER_STARTING, CPUHP_AP_METAG_TIMER_STARTING, + CPUHP_AP_QCOM_TIMER_STARTING, CPUHP_AP_KVM_STARTING, CPUHP_AP_NOTIFY_STARTING, CPUHP_AP_ONLINE, -- 2.8.1