genirq: Add IRQ affinity notifiers (cd7eab44) · Commits · 戴 / test

include/linux/interrupt.h

+32 −1

Original line number	Diff line number	Diff line
		@@ -14,6 +14,8 @@
		#include <linux/smp.h>
		#include <linux/percpu.h>
		#include <linux/hrtimer.h>
		#include <linux/kref.h>
		#include <linux/workqueue.h>

		#include <asm/atomic.h>
		#include <asm/ptrace.h>
		@@ -240,6 +242,35 @@ extern int irq_can_set_affinity(unsigned int irq);
		extern int irq_select_affinity(unsigned int irq);

		extern int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m);

		/**
		* struct irq_affinity_notify - context for notification of IRQ affinity changes
		* @irq: Interrupt to which notification applies
		* @kref: Reference count, for internal use
		* @work: Work item, for internal use
		* @notify: Function to be called on change. This will be
		* called in process context.
		* @release: Function to be called on release. This will be
		* called in process context. Once registered, the
		* structure must only be freed when this function is
		* called or later.
		*/
		struct irq_affinity_notify {
		unsigned int irq;
		struct kref kref;
		struct work_struct work;
		void (notify)(struct irq_affinity_notify , const cpumask_t *mask);
		void (release)(struct kref ref);
		};

		extern int
		irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify);

		static inline void irq_run_affinity_notifiers(void)
		{
		flush_scheduled_work();
		}

		#else /* CONFIG_SMP */

		static inline int irq_set_affinity(unsigned int irq, const struct cpumask *m)

include/linux/irqdesc.h

+3 −0

Original line number	Diff line number	Diff line
		@@ -8,6 +8,7 @@
		* For now it's included from <linux/irq.h>
		*/

		struct irq_affinity_notify;
		struct proc_dir_entry;
		struct timer_rand_state;
		/**
		@@ -24,6 +25,7 @@ struct timer_rand_state;
		* @last_unhandled: aging timer for unhandled count
		* @irqs_unhandled: stats field for spurious unhandled interrupts
		* @lock: locking for SMP
		* @affinity_notify: context for notification of affinity changes
		* @pending_mask: pending rebalanced interrupts
		* @threads_active: number of irqaction threads currently running
		* @wait_for_threads: wait queue for sync_irq to wait for threaded handlers
		@@ -70,6 +72,7 @@ struct irq_desc {
		raw_spinlock_t lock;
		#ifdef CONFIG_SMP
		const struct cpumask *affinity_hint;
		struct irq_affinity_notify *affinity_notify;
		#ifdef CONFIG_GENERIC_PENDING_IRQ
		cpumask_var_t pending_mask;
		#endif

kernel/irq/manage.c

+82 −0

Original line number	Diff line number	Diff line
		@@ -134,6 +134,10 @@ int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
		irq_set_thread_affinity(desc);
		}
		#endif
		if (desc->affinity_notify) {
		kref_get(&desc->affinity_notify->kref);
		schedule_work(&desc->affinity_notify->work);
		}
		desc->status \|= IRQ_AFFINITY_SET;
		raw_spin_unlock_irqrestore(&desc->lock, flags);
		return 0;
		@@ -155,6 +159,79 @@ int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
		}
		EXPORT_SYMBOL_GPL(irq_set_affinity_hint);

		static void irq_affinity_notify(struct work_struct *work)
		{
		struct irq_affinity_notify *notify =
		container_of(work, struct irq_affinity_notify, work);
		struct irq_desc *desc = irq_to_desc(notify->irq);
		cpumask_var_t cpumask;
		unsigned long flags;

		if (!desc)
		goto out;

		if (!alloc_cpumask_var(&cpumask, GFP_KERNEL))
		goto out;

		raw_spin_lock_irqsave(&desc->lock, flags);
		#ifdef CONFIG_GENERIC_PENDING_IRQ
		if (desc->status & IRQ_MOVE_PENDING)
		cpumask_copy(cpumask, desc->pending_mask);
		else
		#endif
		cpumask_copy(cpumask, desc->affinity);
		raw_spin_unlock_irqrestore(&desc->lock, flags);

		notify->notify(notify, cpumask);

		free_cpumask_var(cpumask);
		out:
		kref_put(&notify->kref, notify->release);
		}

		/**
		* irq_set_affinity_notifier - control notification of IRQ affinity changes
		* @irq: Interrupt for which to enable/disable notification
		* @notify: Context for notification, or %NULL to disable
		* notification. Function pointers must be initialised;
		* the other fields will be initialised by this function.
		*
		* Must be called in process context. Notification may only be enabled
		* after the IRQ is allocated and must be disabled before the IRQ is
		* freed using free_irq().
		*/
		int
		irq_set_affinity_notifier(unsigned int irq, struct irq_affinity_notify *notify)
		{
		struct irq_desc *desc = irq_to_desc(irq);
		struct irq_affinity_notify *old_notify;
		unsigned long flags;

		/* The release function is promised process context */
		might_sleep();

		if (!desc)
		return -EINVAL;

		/* Complete initialisation of notify /
		if (notify) {
		notify->irq = irq;
		kref_init(&notify->kref);
		INIT_WORK(&notify->work, irq_affinity_notify);
		}

		raw_spin_lock_irqsave(&desc->lock, flags);
		old_notify = desc->affinity_notify;
		desc->affinity_notify = notify;
		raw_spin_unlock_irqrestore(&desc->lock, flags);

		if (old_notify)
		kref_put(&old_notify->kref, old_notify->release);

		return 0;
		}
		EXPORT_SYMBOL_GPL(irq_set_affinity_notifier);

		#ifndef CONFIG_AUTO_IRQ_AFFINITY
		/*
		* Generic version of the affinity autoselector.
		@@ -1004,6 +1081,11 @@ void free_irq(unsigned int irq, void *dev_id)
		if (!desc)
		return;

		#ifdef CONFIG_SMP
		if (WARN_ON(desc->affinity_notify))
		desc->affinity_notify = NULL;
		#endif

		chip_bus_lock(desc);
		kfree(__free_irq(irq, dev_id));
		chip_bus_sync_unlock(desc);

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