@@ -1449,6 +1449,7 @@ config NR_CPUS
config HOTPLUG_CPU
bool "Support for hot-pluggable CPUs"
depends on SMP
+ select GENERIC_IRQ_MIGRATION
help
Say Y here to experiment with turning CPUs off and on. CPUs
can be controlled through /sys/devices/system/cpu.
@@ -25,7 +25,6 @@
#ifndef __ASSEMBLY__
struct irqaction;
struct pt_regs;
-extern void migrate_irqs(void);
extern void asm_do_IRQ(unsigned int, struct pt_regs *);
void handle_IRQ(unsigned int, struct pt_regs *);
@@ -119,64 +119,3 @@ int __init arch_probe_nr_irqs(void)
return nr_irqs;
}
#endif
-
-#ifdef CONFIG_HOTPLUG_CPU
-static bool migrate_one_irq(struct irq_desc *desc)
-{
- struct irq_data *d = irq_desc_get_irq_data(desc);
- const struct cpumask *affinity = irq_data_get_affinity_mask(d);
- struct irq_chip *c;
- bool ret = false;
-
- /*
- * If this is a per-CPU interrupt, or the affinity does not
- * include this CPU, then we have nothing to do.
- */
- if (irqd_is_per_cpu(d) || !cpumask_test_cpu(smp_processor_id(), affinity))
- return false;
-
- if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) {
- affinity = cpu_online_mask;
- ret = true;
- }
-
- c = irq_data_get_irq_chip(d);
- if (!c->irq_set_affinity)
- pr_debug("IRQ%u: unable to set affinity\n", d->irq);
- else if (c->irq_set_affinity(d, affinity, false) == IRQ_SET_MASK_OK && ret)
- cpumask_copy(irq_data_get_affinity_mask(d), affinity);
-
- return ret;
-}
-
-/*
- * 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 migrate_irqs(void)
-{
- unsigned int i;
- struct irq_desc *desc;
- unsigned long flags;
-
- local_irq_save(flags);
-
- for_each_irq_desc(i, desc) {
- bool affinity_broken;
-
- raw_spin_lock(&desc->lock);
- affinity_broken = migrate_one_irq(desc);
- raw_spin_unlock(&desc->lock);
-
- if (affinity_broken)
- pr_warn_ratelimited("IRQ%u no longer affine to CPU%u\n",
- i, smp_processor_id());
- }
-
- local_irq_restore(flags);
-}
-#endif /* CONFIG_HOTPLUG_CPU */
@@ -225,7 +225,7 @@ int __cpu_disable(void)
/*
* OK - migrate IRQs away from this CPU
*/
- migrate_irqs();
+ irq_migrate_all_off_this_cpu();
/*
* Flush user cache and TLB mappings, and then remove this CPU
I have found that .irq_bus_lock/.irq_bus_sync_unlock of irqchip are not honored during CPU hotplug migration and the reason for this is open-coded IRQ affinity re-configuration in the existing ARM migrate_irqs() implementation. Fortunately, this was already fixed for ARM64 in 217d453d ("arm64: fix a migrating irq bug when hotplug cpu"). So, just switch to the same generic code for ARM. Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> --- arch/arm/Kconfig | 1 + arch/arm/include/asm/irq.h | 1 - arch/arm/kernel/irq.c | 61 -------------------------------------- arch/arm/kernel/smp.c | 2 +- 4 files changed, 2 insertions(+), 63 deletions(-)