From 57b150cce8e004ddd36330490a68bfb59b7271e9 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Mon, 27 Apr 2009 17:59:53 -0700 Subject: irq: only update affinity if ->set_affinity() is sucessfull irq_set_affinity() and move_masked_irq() try to assign affinity before calling chip set_affinity(). Some archs are assigning it in ->set_affinity() again. We do something like: cpumask_cpy(desc->affinity, mask); desc->chip->set_affinity(mask); But in the failure path, affinity should not be touched - otherwise we'll end up with a different affinity mask despite the failure to migrate the IRQ. So try to update the afffinity only if set_affinity returns with 0. Also call irq_set_thread_affinity accordingly. v2: update after "irq, x86: Remove IRQ_DISABLED check in process context IRQ move" v3: according to Ingo, change set_affinity() in irq_chip should return int. v4: update comments by removing moving irq_desc code. [ Impact: fix /proc/irq/*/smp_affinity setting corner case bug ] Signed-off-by: Yinghai Lu Cc: Andrew Morton Cc: Suresh Siddha Cc: "Eric W. Biederman" Cc: Rusty Russell LKML-Reference: <49F65509.60307@kernel.org> Signed-off-by: Ingo Molnar --- kernel/irq/manage.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) (limited to 'kernel/irq/manage.c') diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 2734eca59243..aaf5c9d05770 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -80,7 +80,7 @@ int irq_can_set_affinity(unsigned int irq) return 1; } -static void +void irq_set_thread_affinity(struct irq_desc *desc, const struct cpumask *cpumask) { struct irqaction *action = desc->action; @@ -109,17 +109,22 @@ int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask) spin_lock_irqsave(&desc->lock, flags); #ifdef CONFIG_GENERIC_PENDING_IRQ - if (desc->status & IRQ_MOVE_PCNTXT) - desc->chip->set_affinity(irq, cpumask); + if (desc->status & IRQ_MOVE_PCNTXT) { + if (!desc->chip->set_affinity(irq, cpumask)) { + cpumask_copy(desc->affinity, cpumask); + irq_set_thread_affinity(desc, cpumask); + } + } else { desc->status |= IRQ_MOVE_PENDING; cpumask_copy(desc->pending_mask, cpumask); } #else - cpumask_copy(desc->affinity, cpumask); - desc->chip->set_affinity(irq, cpumask); + if (!desc->chip->set_affinity(irq, cpumask)) { + cpumask_copy(desc->affinity, cpumask); + irq_set_thread_affinity(desc, cpumask); + } #endif - irq_set_thread_affinity(desc, cpumask); desc->status |= IRQ_AFFINITY_SET; spin_unlock_irqrestore(&desc->lock, flags); return 0; -- cgit v1.2.3