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arm64: fix a migrating irq bug when hotplug cpu

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When cpu is disabled, all irqs will be migratged to another cpu.
In some cases, a new affinity is different, the old affinity need
to be updated and if irq_set_affinity's return value is IRQ_SET_MASK_OK_DONE,
the old affinity can not be updated. Fix it by using irq_do_set_affinity.

And migrating interrupts is a core code matter, so use the generic
function irq_migrate_all_off_this_cpu() to migrate interrupts in
kernel/irq/migration.c.

Cc: Jiang Liu <jiang.liu@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Hanjun Guo <hanjun.guo@linaro.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Yang Yingliang 2015-09-24 17:32:14 +08:00 committed by Catalin Marinas
parent a78afccbba
commit 217d453d47
4 changed files with 3 additions and 64 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

1
arch/arm64/Kconfig
View file

@ -427,6 +427,7 @@ config NR_CPUS
config HOTPLUG_CPU
bool "Support for hot-pluggable CPUs"
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.

1
arch/arm64/include/asm/irq.h
View file

@ -7,7 +7,6 @@
struct pt_regs;
extern void migrate_irqs(void);
extern void set_handle_irq(void (*handle_irq)(struct pt_regs *));
static inline void acpi_irq_init(void)

62
arch/arm64/kernel/irq.c
View file

@ -27,7 +27,6 @@
#include <linux/init.h>
#include <linux/irqchip.h>
#include <linux/seq_file.h>
#include <linux/ratelimit.h>
unsigned long irq_err_count;
@ -54,64 +53,3 @@ void __init init_IRQ(void)
if (!handle_arch_irq)
panic("No interrupt controller found.");
}
#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 */

3
arch/arm64/kernel/smp.c
View file

@ -231,7 +231,8 @@ int __cpu_disable(void)
/*
* OK - migrate IRQs away from this CPU
*/
migrate_irqs();
irq_migrate_all_off_this_cpu();
return 0;
}