| Date | Mon, 11 Jul 2016 12:28:52 -0000 | From | Anna-Maria Gleixner <> | Subject | [patch 42/66] clocksource/qcom-timer: Convert to hotplug state machine |
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Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs.
Signed-off-by: Richard Cochran <rcochran@linutronix.de> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> --- drivers/clocksource/qcom-timer.c | 41 ++++++++++----------------------------- include/linux/cpuhotplug.h | 1 2 files changed, 12 insertions(+), 30 deletions(-)
--- a/drivers/clocksource/qcom-timer.c +++ b/drivers/clocksource/qcom-timer.c @@ -105,9 +105,9 @@ static struct clocksource msm_clocksourc 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 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 void __init msm_timer_init(u32 dg 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: --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -42,6 +42,7 @@ enum cpuhp_state { CPUHP_AP_DUMMY_TIMER_STARTING, CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING, CPUHP_AP_METAG_TIMER_STARTING, + CPUHP_AP_QCOM_TIMER_STARTING, CPUHP_AP_KVM_STARTING, CPUHP_AP_NOTIFY_STARTING, CPUHP_AP_ONLINE,
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