linux/kernel/irq/cpuhotplug.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Generic cpu hotunplug interrupt migration code copied from the
 * arch/arm implementation
 *
 * Copyright (C) Russell King
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <linux/interrupt.h>
#include <linux/ratelimit.h>
#include <linux/irq.h>
#include <linux/sched/isolation.h>

#include "internals.h"

/* For !GENERIC_IRQ_EFFECTIVE_AFF_MASK this looks at general affinity mask */
static inline bool irq_needs_fixup(struct irq_data *d)
{ … }

static bool migrate_one_irq(struct irq_desc *desc)
{ … }

/**
 * irq_migrate_all_off_this_cpu - Migrate irqs away from offline cpu
 *
 * The current CPU has been marked offline.  Migrate IRQs off this CPU.
 * If the affinity settings do not allow other CPUs, force them onto any
 * available CPU.
 *
 * Note: we must iterate over all IRQs, whether they have an attached
 * action structure or not, as we need to get chained interrupts too.
 */
void irq_migrate_all_off_this_cpu(void)
{ … }

static bool hk_should_isolate(struct irq_data *data, unsigned int cpu)
{ … }

static void irq_restore_affinity_of_irq(struct irq_desc *desc, unsigned int cpu)
{ … }

/**
 * irq_affinity_online_cpu - Restore affinity for managed interrupts
 * @cpu:	Upcoming CPU for which interrupts should be restored
 */
int irq_affinity_online_cpu(unsigned int cpu)
{ … }