Merge "hrtimer: Don't drop the base lock when migration during isolation" (c42a087f) · Commits · e / devices / android_kernel_fairphone_FP3

kernel/time/hrtimer.c

+14 −35

Original line number	Diff line number	Diff line
		@@ -49,7 +49,6 @@
		#include <linux/sched/deadline.h>
		#include <linux/timer.h>
		#include <linux/freezer.h>
		#include <linux/delay.h>

		#include <asm/uaccess.h>

		@@ -1579,41 +1578,22 @@ int hrtimers_prepare_cpu(unsigned int cpu)
		}

		#ifdef CONFIG_HOTPLUG_CPU
		static void migrate_hrtimer_list(struct hrtimer_cpu_base *old_base,
		struct hrtimer_cpu_base *new_base,
		unsigned int i, bool wait,
		static void migrate_hrtimer_list(struct hrtimer_clock_base *old_base,
		struct hrtimer_clock_base *new_base,
		bool remove_pinned)
		{
		struct hrtimer *timer;
		struct timerqueue_node *node;
		struct timerqueue_head pinned;
		int is_pinned;
		struct hrtimer_clock_base *old_c_base = &old_base->clock_base[i];
		struct hrtimer_clock_base *new_c_base = &new_base->clock_base[i];
		bool is_hotplug = !cpu_online(old_base->cpu_base->cpu);

		timerqueue_init_head(&pinned);

		while ((node = timerqueue_getnext(&old_c_base->active))) {
		while ((node = timerqueue_getnext(&old_base->active))) {
		timer = container_of(node, struct hrtimer, node);
		if (wait) {
		/* Ensure timers are done running before continuing */
		while (hrtimer_callback_running(timer)) {
		raw_spin_unlock(&old_base->lock);
		raw_spin_unlock(&new_base->lock);
		cpu_relax();
		/*
		* cpu_relax may just be a barrier. Grant the
		* run_hrtimer_list code some time to obtain
		* the spinlock.
		*/
		udelay(1);
		raw_spin_lock(&new_base->lock);
		raw_spin_lock_nested(&old_base->lock,
		SINGLE_DEPTH_NESTING);
		}
		} else {
		if (is_hotplug)
		BUG_ON(hrtimer_callback_running(timer));
		}
		debug_deactivate(timer);

		/*
		@@ -1621,7 +1601,7 @@ static void migrate_hrtimer_list(struct hrtimer_cpu_base *old_base,
		* timer could be seen as !active and just vanish away
		* under us on another CPU
		*/
		__remove_hrtimer(timer, old_c_base, HRTIMER_STATE_ENQUEUED, 0);
		__remove_hrtimer(timer, old_base, HRTIMER_STATE_ENQUEUED, 0);

		is_pinned = timer->state & HRTIMER_STATE_PINNED;
		if (!remove_pinned && is_pinned) {
		@@ -1629,7 +1609,7 @@ static void migrate_hrtimer_list(struct hrtimer_cpu_base *old_base,
		continue;
		}

		timer->base = new_c_base;
		timer->base = new_base;
		/*
		* Enqueue the timers on the new cpu. This does not
		* reprogram the event device in case the timer
		@@ -1638,7 +1618,7 @@ static void migrate_hrtimer_list(struct hrtimer_cpu_base *old_base,
		* sort out already expired timers and reprogram the
		* event device.
		*/
		enqueue_hrtimer(timer, new_c_base);
		enqueue_hrtimer(timer, new_base);
		}

		/* Re-queue pinned timers for non-hotplug usecase */
		@@ -1646,12 +1626,11 @@ static void migrate_hrtimer_list(struct hrtimer_cpu_base *old_base,
		timer = container_of(node, struct hrtimer, node);

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

		static void
		__migrate_hrtimers(unsigned int scpu, bool wait, bool remove_pinned)
		static void __migrate_hrtimers(unsigned int scpu, bool remove_pinned)
		{
		struct hrtimer_cpu_base old_base, new_base;
		unsigned long flags;
		@@ -1668,8 +1647,8 @@ __migrate_hrtimers(unsigned int scpu, bool wait, bool remove_pinned)
		raw_spin_lock_nested(&old_base->lock, SINGLE_DEPTH_NESTING);

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

		raw_spin_unlock(&old_base->lock);
		@@ -1685,13 +1664,13 @@ int hrtimers_dead_cpu(unsigned int scpu)
		BUG_ON(cpu_online(scpu));
		tick_cancel_sched_timer(scpu);

		__migrate_hrtimers(scpu, false, true);
		__migrate_hrtimers(scpu, true);
		return 0;
		}

		void hrtimer_quiesce_cpu(void *cpup)
		{
		__migrate_hrtimers((int )cpup, true, false);
		__migrate_hrtimers((int )cpup, false);
		}

		#endif /* CONFIG_HOTPLUG_CPU */