Merge "sched: Add a check for cpu unbound deferrable timers" (451bc6e4) · Commits · e / devices / android_kernel_xiaomi_markw

include/linux/timer.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -190,6 +190,9 @@ extern int mod_timer_pending(struct timer_list *timer, unsigned long expires);
		extern int mod_timer_pinned(struct timer_list *timer, unsigned long expires);

		extern void set_timer_slack(struct timer_list *time, int slack_hz);
		#ifdef CONFIG_SMP
		extern bool check_pending_deferrable_timers(int cpu);
		#endif

		#define TIMER_NOT_PINNED 0
		#define TIMER_PINNED 1

kernel/time/tick-sched.c

+6 −0

Original line number	Diff line number	Diff line
		@@ -19,6 +19,7 @@
		#include <linux/percpu.h>
		#include <linux/profile.h>
		#include <linux/sched.h>
		#include <linux/timer.h>
		#include <linux/module.h>
		#include <linux/irq_work.h>
		#include <linux/posix-timers.h>
		@@ -829,6 +830,11 @@ static void __tick_nohz_idle_enter(struct tick_sched *ts)

		now = tick_nohz_start_idle(ts);

		#ifdef CONFIG_SMP
		if (check_pending_deferrable_timers(cpu))
		raise_softirq_irqoff(TIMER_SOFTIRQ);
		#endif

		if (can_stop_idle_tick(cpu, ts)) {
		int was_stopped = ts->tick_stopped;

kernel/time/timer.c

+32 −3

Original line number	Diff line number	Diff line
		@@ -97,6 +97,7 @@ EXPORT_SYMBOL(boot_tvec_bases);
		static DEFINE_PER_CPU(struct tvec_base *, tvec_bases) = &boot_tvec_bases;
		#ifdef CONFIG_SMP
		struct tvec_base tvec_base_deferrable;
		static atomic_t deferrable_pending;
		#endif

		static inline void __run_timers(struct tvec_base *base);
		@@ -676,9 +677,13 @@ static inline bool is_deferrable_timer_base(struct tvec_base *base)

		static inline void __run_deferrable_timers(void)
		{
		if (smp_processor_id() == tick_do_timer_cpu &&
		time_after_eq(jiffies, tvec_base_deferrable.timer_jiffies))
		if (time_after_eq(jiffies, tvec_base_deferrable.timer_jiffies)) {
		if ((atomic_cmpxchg(&deferrable_pending, 1, 0) &&
		tick_do_timer_cpu == TICK_DO_TIMER_NONE) \|\|
		tick_do_timer_cpu == smp_processor_id())
		__run_timers(&tvec_base_deferrable);

		}
		}

		static inline void init_deferrable_timer(void)
		@@ -1402,6 +1407,30 @@ static unsigned long cmp_next_hrtimer_event(unsigned long now,
		return expires;
		}

		#ifdef CONFIG_SMP
		/*
		* check_pending_deferrable_timers - Check for unbound deferrable timer expiry.
		* @cpu - Current CPU
		*
		* The function checks whether any global deferrable pending timers
		* are exipired or not. This function does not check cpu bounded
		* diferrable pending timers expiry.
		*
		* The function returns true when a cpu unbounded deferrable timer is expired.
		*/
		bool check_pending_deferrable_timers(int cpu)
		{
		if (cpu == tick_do_timer_cpu \|\|
		tick_do_timer_cpu == TICK_DO_TIMER_NONE) {
		if (time_after_eq(jiffies, tvec_base_deferrable.timer_jiffies)
		&& !atomic_cmpxchg(&deferrable_pending, 0, 1)) {
		return true;
		}
		}
		return false;
		}
		#endif

		/**
		* get_next_timer_interrupt - return the jiffy of the next pending timer
		* @now: current time (in jiffies)