1 // SPDX-License-Identifier: GPL-2.0
3  * Generic cpu hotunplug interrupt migration code copied from the
19 /* For !GENERIC_IRQ_EFFECTIVE_AFF_MASK this looks at general affinity mask */
23 	unsigned int cpu = smp_processor_id();  in irq_needs_fixup()  local
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()
36 	 * CPU then it must contain at least one online CPU. The outgoing CPU  in irq_needs_fixup()
39 	if (cpumask_any_but(m, cpu) < nr_cpu_ids &&  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()
50 	return cpumask_test_cpu(cpu, m);  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()
76 	 * happens and this CPU was involved.  in migrate_one_irq()
82 	 * - Interrupt is per cpu  in migrate_one_irq()
83 	 * - Interrupt is not started  in migrate_one_irq()
84 	 * - Affinity mask does not include this CPU.  in migrate_one_irq()
86 	 * Note: Do not check desc->action as this might be a chained  in migrate_one_irq()
91 		 * If an irq move is pending, abort it if the dying CPU is  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_intersects(affinity, cpu_online_mask)) {  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()
130 	 * CPU.  in migrate_one_irq()
132 	err = irq_do_set_affinity(d, affinity, false);  in migrate_one_irq()
135 	 * If there are online CPUs in the affinity mask, but they have no  in migrate_one_irq()
137 	 * affinity by migrating to any online CPU.  in migrate_one_irq()
139 	if (err == -ENOSPC && !irqd_affinity_is_managed(d) && affinity != cpu_online_mask) {  in migrate_one_irq()
140 		pr_debug("IRQ%u: set affinity failed for %*pbl, re-try with online CPUs\n",  in migrate_one_irq()
141 			 d->irq, cpumask_pr_args(affinity));  in migrate_one_irq()
143 		affinity = cpu_online_mask;  in migrate_one_irq()
146 		err = irq_do_set_affinity(d, affinity, false);  in migrate_one_irq()
150 		pr_warn_ratelimited("IRQ%u: set affinity failed(%d).\n",  in migrate_one_irq()
151 				    d->irq, err);  in migrate_one_irq()
155 	if (maskchip && chip->irq_unmask)  in migrate_one_irq()
156 		chip->irq_unmask(d);  in migrate_one_irq()
162  * irq_migrate_all_off_this_cpu - Migrate irqs away from offline cpu
164  * The current CPU has been marked offline.  Migrate IRQs off this CPU.
165  * If the affinity settings do not allow other CPUs, force them onto any
166  * available CPU.
180 		scoped_guard(raw_spinlock, &desc->lock)  in irq_migrate_all_off_this_cpu()
184 			pr_debug_ratelimited("IRQ %u: no longer affine to CPU%u\n",  in irq_migrate_all_off_this_cpu()
190 static bool hk_should_isolate(struct irq_data *data, unsigned int cpu)  in hk_should_isolate()  argument
201 	return cpumask_test_cpu(cpu, hk_mask);  in hk_should_isolate()
204 static void irq_restore_affinity_of_irq(struct irq_desc *desc, unsigned int cpu)  in irq_restore_affinity_of_irq()  argument
207 	const struct cpumask *affinity = irq_data_get_affinity_mask(data);  in irq_restore_affinity_of_irq()  local
209 	if (!irqd_affinity_is_managed(data) || !desc->action ||  in irq_restore_affinity_of_irq()
210 	    !irq_data_get_irq_chip(data) || !cpumask_test_cpu(cpu, affinity))  in irq_restore_affinity_of_irq()
217 	 * If the interrupt can only be directed to a single target  in irq_restore_affinity_of_irq()
218 	 * CPU then it is already assigned to a CPU in the affinity  in irq_restore_affinity_of_irq()
221 	 * housekeeping CPU.  in irq_restore_affinity_of_irq()
223 	if (!irqd_is_single_target(data) || hk_should_isolate(data, cpu))  in irq_restore_affinity_of_irq()
224 		irq_set_affinity_locked(data, affinity, false);  in irq_restore_affinity_of_irq()
228  * irq_affinity_online_cpu - Restore affinity for managed interrupts
229  * @cpu:	Upcoming CPU for which interrupts should be restored
231 int irq_affinity_online_cpu(unsigned int cpu)  in irq_affinity_online_cpu()  argument
239 		scoped_guard(raw_spinlock_irq, &desc->lock)  in irq_affinity_online_cpu()
240 			irq_restore_affinity_of_irq(desc, cpu);  in irq_affinity_online_cpu()