Merge "hrtimer: create hrtimer_quiesce_cpu() to isolate CPU from hrtimers" (02634498) · Commits · e / devices / android_kernel_oneplus_sm8150

include/linux/hrtimer.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -344,6 +344,9 @@ DECLARE_PER_CPU(struct tick_device, tick_cpu_device);

		/* 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

+44 −11

Original line number	Diff line number	Diff line
		@@ -1605,13 +1605,17 @@ 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);
		@@ -1624,6 +1628,13 @@ 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
		@@ -1635,17 +1646,23 @@ static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
		*/
		enqueue_hrtimer(timer, new_base);
		}

		/* 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);
		}
		}

		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);

		local_irq_disable();
		local_irq_save(flags);
		old_base = &per_cpu(hrtimer_bases, scpu);
		new_base = this_cpu_ptr(&hrtimer_bases);
		/*
		@@ -1657,7 +1674,7 @@ 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);
		}

		raw_spin_unlock(&old_base->lock);
		@@ -1665,12 +1682,28 @@ int hrtimers_dead_cpu(unsigned int scpu)

		/* Check, if we got expired work to do */
		__hrtimer_peek_ahead_timers();
		local_irq_enable();
		return 0;
		local_irq_restore(flags);
		}
		#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());