clocksource/arm_global_timer: 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 <rcochran@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Maxime Coquelin <maxime.coquelin@st.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srinivas Kandagatla <srinivas.kandagatla@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kernel@stlinux.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153338.062741642@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Richard Cochran 2016-07-13 17:17:04 +00:00 committed by Ingo Molnar
parent 4df8374254
commit b8a12296ac
2 changed files with 11 additions and 29 deletions

View File

@ -165,9 +165,9 @@ static irqreturn_t gt_clockevent_interrupt(int irq, void *dev_id)
return IRQ_HANDLED;
}
static int gt_clockevents_init(struct clock_event_device *clk)
static int gt_starting_cpu(unsigned int cpu)
{
int cpu = smp_processor_id();
struct clock_event_device *clk = this_cpu_ptr(gt_evt);
clk->name = "arm_global_timer";
clk->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
@ -186,10 +186,13 @@ static int gt_clockevents_init(struct clock_event_device *clk)
return 0;
}
static void gt_clockevents_stop(struct clock_event_device *clk)
static int gt_dying_cpu(unsigned int cpu)
{
struct clock_event_device *clk = this_cpu_ptr(gt_evt);
gt_clockevent_shutdown(clk);
disable_percpu_irq(clk->irq);
return 0;
}
static cycle_t gt_clocksource_read(struct clocksource *cs)
@ -252,24 +255,6 @@ static int __init gt_clocksource_init(void)
return clocksource_register_hz(&gt_clocksource, gt_clk_rate);
}
static int gt_cpu_notify(struct notifier_block *self, unsigned long action,
void *hcpu)
{
switch (action & ~CPU_TASKS_FROZEN) {
case CPU_STARTING:
gt_clockevents_init(this_cpu_ptr(gt_evt));
break;
case CPU_DYING:
gt_clockevents_stop(this_cpu_ptr(gt_evt));
break;
}
return NOTIFY_OK;
}
static struct notifier_block gt_cpu_nb = {
.notifier_call = gt_cpu_notify,
};
static int __init global_timer_of_register(struct device_node *np)
{
struct clk *gt_clk;
@ -325,18 +310,14 @@ static int __init global_timer_of_register(struct device_node *np)
goto out_free;
}
err = register_cpu_notifier(&gt_cpu_nb);
if (err) {
pr_warn("global-timer: unable to register cpu notifier.\n");
goto out_irq;
}
/* Immediately configure the timer on the boot CPU */
/* Register and immediately configure the timer on the boot CPU */
err = gt_clocksource_init();
if (err)
goto out_irq;
err = gt_clockevents_init(this_cpu_ptr(gt_evt));
err = cpuhp_setup_state(CPUHP_AP_ARM_GLOBAL_TIMER_STARTING,
"AP_ARM_GLOBAL_TIMER_STARTING",
gt_starting_cpu, gt_dying_cpu);
if (err)
goto out_irq;

View File

@ -47,6 +47,7 @@ enum cpuhp_state {
CPUHP_AP_PERF_ARM_STARTING,
CPUHP_AP_ARM_L2X0_STARTING,
CPUHP_AP_ARM_ARCH_TIMER_STARTING,
CPUHP_AP_ARM_GLOBAL_TIMER_STARTING,
CPUHP_AP_DUMMY_TIMER_STARTING,
CPUHP_AP_ARM_TWD_STARTING,
CPUHP_AP_METAG_TIMER_STARTING,