Merge "hrtimer: make sure PINNED flag is cleared after removing hrtimer" (a7abbe4f) · Commits · e / devices / android_kernel_fairphone_FP5

include/linux/hrtimer.h

+6 −0

Original line number	Diff line number	Diff line
		@@ -73,6 +73,7 @@ enum hrtimer_restart {
		*
		* 0x00 inactive
		* 0x01 enqueued into rbtree
		* 0x02 timer is pinned to a cpu
		*
		* The callback state is not part of the timer->state because clearing it would
		* mean touching the timer after the callback, this makes it impossible to free
		@@ -92,6 +93,8 @@ enum hrtimer_restart {
		*/
		#define HRTIMER_STATE_INACTIVE 0x00
		#define HRTIMER_STATE_ENQUEUED 0x01
		#define HRTIMER_PINNED_SHIFT 1
		#define HRTIMER_STATE_PINNED (1 << HRTIMER_PINNED_SHIFT)

		/**
		* struct hrtimer - the basic hrtimer structure
		@@ -371,6 +374,9 @@ static inline void hrtimer_cancel_wait_running(struct hrtimer *timer)

		/* Exported timer functions: */

		/* To be used from cpusets, only */
		extern void hrtimer_quiesce_cpu(void *cpup);

		/* Initialize timers: */
		extern void hrtimer_init(struct hrtimer *timer, clockid_t which_clock,
		enum hrtimer_mode mode);

kernel/time/hrtimer.c

+59 −16

Original line number	Diff line number	Diff line
		@@ -966,7 +966,7 @@ static int enqueue_hrtimer(struct hrtimer *timer,

		base->cpu_base->active_bases \|= 1 << base->index;

		timer->state = HRTIMER_STATE_ENQUEUED;
		timer->state \|= HRTIMER_STATE_ENQUEUED;

		return timerqueue_add(&base->active, &timer->node);
		}
		@@ -986,11 +986,9 @@ static void __remove_hrtimer(struct hrtimer *timer,
		u8 newstate, int reprogram)
		{
		struct hrtimer_cpu_base *cpu_base = base->cpu_base;
		u8 state = timer->state;

		timer->state = newstate;
		if (!(state & HRTIMER_STATE_ENQUEUED))
		return;
		if (!(timer->state & HRTIMER_STATE_ENQUEUED))
		goto out;

		if (!timerqueue_del(&base->active, &timer->node))
		cpu_base->active_bases &= ~(1 << base->index);
		@@ -1005,6 +1003,13 @@ static void __remove_hrtimer(struct hrtimer *timer,
		*/
		if (reprogram && timer == cpu_base->next_timer)
		hrtimer_force_reprogram(cpu_base, 1);

		out:
		/*
		* We need to preserve PINNED state here, otherwise we may end up
		* migrating pinned hrtimers as well.
		*/
		timer->state = newstate \| (timer->state & HRTIMER_STATE_PINNED);
		}

		/*
		@@ -1032,6 +1037,7 @@ remove_hrtimer(struct hrtimer timer, struct hrtimer_clock_base base, bool rest
		state = HRTIMER_STATE_INACTIVE;

		__remove_hrtimer(timer, base, state, reprogram);
		timer->state &= ~HRTIMER_STATE_PINNED;
		return 1;
		}
		return 0;
		@@ -1097,6 +1103,10 @@ static int __hrtimer_start_range_ns(struct hrtimer *timer, ktime_t tim,
		/* Switch the timer base, if necessary: */
		new_base = switch_hrtimer_base(timer, base, mode & HRTIMER_MODE_PINNED);

		/* Update pinned state */
		timer->state &= ~HRTIMER_STATE_PINNED;
		timer->state \|= (!!(mode & HRTIMER_MODE_PINNED)) << HRTIMER_PINNED_SHIFT;

		return enqueue_hrtimer(timer, new_base, mode);
		}

		@@ -2004,13 +2014,17 @@ int hrtimers_prepare_cpu(unsigned int cpu)
		return 0;
		}

		#ifdef CONFIG_HOTPLUG_CPU

		#if defined(CONFIG_HOTPLUG_CPU) \|\| defined(CONFIG_CPUSETS)
		static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
		struct hrtimer_clock_base *new_base)
		struct hrtimer_clock_base *new_base,
		bool remove_pinned)
		{
		struct hrtimer *timer;
		struct timerqueue_node *node;
		struct timerqueue_head pinned;
		int is_pinned;

		timerqueue_init_head(&pinned);

		while ((node = timerqueue_getnext(&old_base->active))) {
		timer = container_of(node, struct hrtimer, node);
		@@ -2023,6 +2037,13 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
		* under us on another CPU
		*/
		__remove_hrtimer(timer, old_base, HRTIMER_STATE_ENQUEUED, 0);

		is_pinned = timer->state & HRTIMER_STATE_PINNED;
		if (!remove_pinned && is_pinned) {
		timerqueue_add(&pinned, &timer->node);
		continue;
		}

		timer->base = new_base;
		/*
		* Enqueue the timers on the new cpu. This does not
		@@ -2034,23 +2055,29 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
		*/
		enqueue_hrtimer(timer, new_base, HRTIMER_MODE_ABS);
		}

		/* Re-queue pinned timers for non-hotplug usecase */
		while ((node = timerqueue_getnext(&pinned))) {
		timer = container_of(node, struct hrtimer, node);

		timerqueue_del(&pinned, &timer->node);
		enqueue_hrtimer(timer, old_base, HRTIMER_MODE_ABS);
		}
		}

		int hrtimers_dead_cpu(unsigned int scpu)
		static void __migrate_hrtimers(unsigned int scpu, bool remove_pinned)
		{
		struct hrtimer_cpu_base old_base, new_base;
		unsigned long flags;
		int i;

		BUG_ON(cpu_online(scpu));
		tick_cancel_sched_timer(scpu);

		/*
		* this BH disable ensures that raise_softirq_irqoff() does
		* not wakeup ksoftirqd (and acquire the pi-lock) while
		* holding the cpu_base lock
		*/
		local_bh_disable();
		local_irq_disable();
		local_irq_save(flags);
		old_base = &per_cpu(hrtimer_bases, scpu);
		new_base = this_cpu_ptr(&hrtimer_bases);
		/*
		@@ -2062,7 +2089,7 @@ int hrtimers_dead_cpu(unsigned int scpu)

		for (i = 0; i < HRTIMER_MAX_CLOCK_BASES; i++) {
		migrate_hrtimer_list(&old_base->clock_base[i],
		&new_base->clock_base[i]);
		&new_base->clock_base[i], remove_pinned);
		}

		/*
		@@ -2076,13 +2103,29 @@ int hrtimers_dead_cpu(unsigned int scpu)

		/* Check, if we got expired work to do */
		__hrtimer_peek_ahead_timers();
		local_irq_enable();
		local_irq_restore(flags);
		local_bh_enable();
		return 0;
		}
		#endif /* CONFIG_HOTPLUG_CPU \|\| CONFIG_CPUSETS */

		#ifdef CONFIG_HOTPLUG_CPU
		int hrtimers_dead_cpu(unsigned int scpu)
		{
		BUG_ON(cpu_online(scpu));
		tick_cancel_sched_timer(scpu);

		__migrate_hrtimers(scpu, true);
		return 0;
		}
		#endif /* CONFIG_HOTPLUG_CPU */

		#ifdef CONFIG_CPUSETS
		void hrtimer_quiesce_cpu(void *cpup)
		{
		__migrate_hrtimers((int )cpup, false);
		}
		#endif /* CONFIG_CPUSETS */

		void __init hrtimers_init(void)
		{
		hrtimers_prepare_cpu(smp_processor_id());