From 2dab90932fd08f101a45acc0495ccd77b869da5d Mon Sep 17 00:00:00 2001 From: Richard Cochran Date: Wed, 13 Jul 2016 17:16:44 +0000 Subject: [PATCH] clocksource/mips-gic: Convert to hotplug state machine Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs. Signed-off-by: Richard Cochran Signed-off-by: Anna-Maria Gleixner Reviewed-by: Sebastian Andrzej Siewior Cc: Daniel Lezcano Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: rt@linutronix.de Link: http://lkml.kernel.org/r/20160713153336.380737946@linutronix.de Signed-off-by: Ingo Molnar --- drivers/clocksource/mips-gic-timer.c | 38 ++++++++++------------------ include/linux/cpuhotplug.h | 1 + 2 files changed, 14 insertions(+), 25 deletions(-) diff --git a/drivers/clocksource/mips-gic-timer.c b/drivers/clocksource/mips-gic-timer.c index 1572c7a778ab..d91e8725917c 100644 --- a/drivers/clocksource/mips-gic-timer.c +++ b/drivers/clocksource/mips-gic-timer.c @@ -49,10 +49,9 @@ struct irqaction gic_compare_irqaction = { .name = "timer", }; -static void gic_clockevent_cpu_init(struct clock_event_device *cd) +static void gic_clockevent_cpu_init(unsigned int cpu, + struct clock_event_device *cd) { - unsigned int cpu = smp_processor_id(); - cd->name = "MIPS GIC"; cd->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP; @@ -79,19 +78,10 @@ static void gic_update_frequency(void *data) clockevents_update_freq(this_cpu_ptr(&gic_clockevent_device), rate); } -static int gic_cpu_notifier(struct notifier_block *nb, unsigned long action, - void *data) +static int gic_starting_cpu(unsigned int cpu) { - switch (action & ~CPU_TASKS_FROZEN) { - case CPU_STARTING: - gic_clockevent_cpu_init(this_cpu_ptr(&gic_clockevent_device)); - break; - case CPU_DYING: - gic_clockevent_cpu_exit(this_cpu_ptr(&gic_clockevent_device)); - break; - } - - return NOTIFY_OK; + gic_clockevent_cpu_init(cpu, this_cpu_ptr(&gic_clockevent_device)); + return 0; } static int gic_clk_notifier(struct notifier_block *nb, unsigned long action, @@ -105,10 +95,11 @@ static int gic_clk_notifier(struct notifier_block *nb, unsigned long action, return NOTIFY_OK; } - -static struct notifier_block gic_cpu_nb = { - .notifier_call = gic_cpu_notifier, -}; +static int gic_dying_cpu(unsigned int cpu) +{ + gic_clockevent_cpu_exit(this_cpu_ptr(&gic_clockevent_device)); + return 0; +} static struct notifier_block gic_clk_nb = { .notifier_call = gic_clk_notifier, @@ -125,12 +116,9 @@ static int gic_clockevent_init(void) if (ret < 0) return ret; - ret = register_cpu_notifier(&gic_cpu_nb); - if (ret < 0) - pr_warn("GIC: Unable to register CPU notifier\n"); - - gic_clockevent_cpu_init(this_cpu_ptr(&gic_clockevent_device)); - + cpuhp_setup_state(CPUHP_AP_MIPS_GIC_TIMER_STARTING, + "AP_MIPS_GIC_TIMER_STARTING", gic_starting_cpu, + gic_dying_cpu); return 0; } diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index d74d15a028e4..456e3d93272c 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -40,6 +40,7 @@ enum cpuhp_state { CPUHP_AP_DUMMY_TIMER_STARTING, CPUHP_AP_METAG_TIMER_STARTING, CPUHP_AP_QCOM_TIMER_STARTING, + CPUHP_AP_MIPS_GIC_TIMER_STARTING, CPUHP_AP_KVM_STARTING, CPUHP_AP_NOTIFY_STARTING, CPUHP_AP_ONLINE, -- 2.20.1