1 // SPDX-License-Identifier: GPL-2.0
3  * Generic cpu hotunplug interrupt migration code copied from the
12 #include <linux/interrupt.h>
19 /* For !GENERIC_IRQ_EFFECTIVE_AFF_MASK this looks at general affinity mask */
27 	 * The cpumask_empty() check is a workaround for interrupt chips,  in irq_needs_fixup()
28 	 * which do not implement effective affinity, but the architecture has  in irq_needs_fixup()
29 	 * enabled the config switch. Use the general affinity mask instead.  in irq_needs_fixup()
45 		pr_warn("Eff. affinity %*pbl of IRQ %u contains only offline CPUs after offlining CPU %u\n",  in irq_needs_fixup()
46 			cpumask_pr_args(m), d->irq, cpu);  in irq_needs_fixup()
58 	const struct cpumask *affinity;  in migrate_one_irq()  local
64 	 * still in the radix tree. Also if the chip has no affinity setter,  in migrate_one_irq()
67 	if (!chip || !chip->irq_set_affinity) {  in migrate_one_irq()
68 		pr_debug("IRQ %u: Unable to migrate away\n", d->irq);  in migrate_one_irq()
74 	 * - Interrupt is per cpu  in migrate_one_irq()
75 	 * - Interrupt is not started  in migrate_one_irq()
76 	 * - Affinity mask does not include this CPU.  in migrate_one_irq()
78 	 * Note: Do not check desc->action as this might be a chained  in migrate_one_irq()
79 	 * interrupt.  in migrate_one_irq()
92 	 * interrupt was moved in hard irq context, then the vectors need  in migrate_one_irq()
93 	 * to be cleaned up. It can't wait until this interrupt actually  in migrate_one_irq()
100 	 * mask, so the last change of the affinity does not get lost. If  in migrate_one_irq()
102 	 * any online CPU, use the current affinity mask.  in migrate_one_irq()
105 		affinity = irq_desc_get_pending_mask(desc);  in migrate_one_irq()
107 		affinity = irq_data_get_affinity_mask(d);  in migrate_one_irq()
110 	if (maskchip && chip->irq_mask)  in migrate_one_irq()
111 		chip->irq_mask(d);  in migrate_one_irq()
113 	if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) {  in migrate_one_irq()
115 		 * If the interrupt is managed, then shut it down and leave  in migrate_one_irq()
116 		 * the affinity untouched.  in migrate_one_irq()
123 		affinity = cpu_online_mask;  in migrate_one_irq()
128 	 * disables the masking of offline CPUs from the supplied affinity  in migrate_one_irq()
132 	err = irq_do_set_affinity(d, affinity, false);  in migrate_one_irq()
134 		pr_warn_ratelimited("IRQ%u: set affinity failed(%d).\n",  in migrate_one_irq()
135 				    d->irq, err);  in migrate_one_irq()
139 	if (maskchip && chip->irq_unmask)  in migrate_one_irq()
140 		chip->irq_unmask(d);  in migrate_one_irq()
146  * irq_migrate_all_off_this_cpu - Migrate irqs away from offline cpu
149  * If the affinity settings do not allow other CPUs, force them onto any
164 		raw_spin_lock(&desc->lock);  in irq_migrate_all_off_this_cpu()
166 		raw_spin_unlock(&desc->lock);  in irq_migrate_all_off_this_cpu()
192 	const struct cpumask *affinity = irq_data_get_affinity_mask(data);  in irq_restore_affinity_of_irq()  local
194 	if (!irqd_affinity_is_managed(data) || !desc->action ||  in irq_restore_affinity_of_irq()
195 	    !irq_data_get_irq_chip(data) || !cpumask_test_cpu(cpu, affinity))  in irq_restore_affinity_of_irq()
204 	 * If the interrupt can only be directed to a single target  in irq_restore_affinity_of_irq()
205 	 * CPU then it is already assigned to a CPU in the affinity  in irq_restore_affinity_of_irq()
211 		irq_set_affinity_locked(data, affinity, false);  in irq_restore_affinity_of_irq()
215  * irq_affinity_online_cpu - Restore affinity for managed interrupts
226 		raw_spin_lock_irq(&desc->lock);  in irq_affinity_online_cpu()
228 		raw_spin_unlock_irq(&desc->lock);  in irq_affinity_online_cpu()