[PATCH v10 12/14] x86, hotplug: Handle retrigger irq by the first available CPU

From: Fenghua Yu
Date: Tue Nov 13 2012 - 21:34:21 EST


From: Fenghua Yu <fenghua.yu@xxxxxxxxx>

The first cpu in irq cfg->domain is likely to be CPU 0 and may not be available
when CPU 0 is offline. Instead of using CPU 0 to handle retriggered irq, we use
first available CPU which is online and in this irq's domain.

Signed-off-by: Fenghua Yu <fenghua.yu@xxxxxxxxx>
---
arch/x86/kernel/apic/io_apic.c | 4 +++-
1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index b134f0b..c94bac8 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -2199,9 +2199,11 @@ static int ioapic_retrigger_irq(struct irq_data *data)
{
struct irq_cfg *cfg = data->chip_data;
unsigned long flags;
+ int cpu;

raw_spin_lock_irqsave(&vector_lock, flags);
- apic->send_IPI_mask(cpumask_of(cpumask_first(cfg->domain)), cfg->vector);
+ cpu = cpumask_first_and(cfg->domain, cpu_online_mask);
+ apic->send_IPI_mask(cpumask_of(cpu), cfg->vector);
raw_spin_unlock_irqrestore(&vector_lock, flags);

return 1;
--
1.7.2

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