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82 lines
2.1 KiB
82 lines
2.1 KiB
/* |
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* Generic cpu hotunplug interrupt migration code copied from the |
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* arch/arm implementation |
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* |
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* Copyright (C) Russell King |
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* |
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* This program is free software; you can redistribute it and/or modify |
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* it under the terms of the GNU General Public License version 2 as |
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* published by the Free Software Foundation. |
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*/ |
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#include <linux/interrupt.h> |
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#include <linux/ratelimit.h> |
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#include <linux/irq.h> |
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#include "internals.h" |
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static bool migrate_one_irq(struct irq_desc *desc) |
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{ |
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struct irq_data *d = irq_desc_get_irq_data(desc); |
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const struct cpumask *affinity = d->common->affinity; |
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struct irq_chip *c; |
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bool ret = false; |
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/* |
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* If this is a per-CPU interrupt, or the affinity does not |
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* include this CPU, then we have nothing to do. |
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*/ |
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if (irqd_is_per_cpu(d) || |
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!cpumask_test_cpu(smp_processor_id(), affinity)) |
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return false; |
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if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) { |
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affinity = cpu_online_mask; |
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ret = true; |
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} |
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c = irq_data_get_irq_chip(d); |
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if (!c->irq_set_affinity) { |
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pr_debug("IRQ%u: unable to set affinity\n", d->irq); |
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} else { |
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int r = irq_do_set_affinity(d, affinity, false); |
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if (r) |
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pr_warn_ratelimited("IRQ%u: set affinity failed(%d).\n", |
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d->irq, r); |
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} |
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return ret; |
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} |
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/** |
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* irq_migrate_all_off_this_cpu - Migrate irqs away from offline cpu |
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* |
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* The current CPU has been marked offline. Migrate IRQs off this CPU. |
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* If the affinity settings do not allow other CPUs, force them onto any |
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* available CPU. |
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* |
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* Note: we must iterate over all IRQs, whether they have an attached |
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* action structure or not, as we need to get chained interrupts too. |
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*/ |
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void irq_migrate_all_off_this_cpu(void) |
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{ |
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unsigned int irq; |
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struct irq_desc *desc; |
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unsigned long flags; |
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local_irq_save(flags); |
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for_each_active_irq(irq) { |
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bool affinity_broken; |
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desc = irq_to_desc(irq); |
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raw_spin_lock(&desc->lock); |
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affinity_broken = migrate_one_irq(desc); |
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raw_spin_unlock(&desc->lock); |
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if (affinity_broken) |
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pr_warn_ratelimited("IRQ%u no longer affine to CPU%u\n", |
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irq, smp_processor_id()); |
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} |
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local_irq_restore(flags); |
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}
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