diff options
Diffstat (limited to 'kernel/irq/manage.c')
| -rw-r--r-- | kernel/irq/manage.c | 50 |
1 files changed, 44 insertions, 6 deletions
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 50da6767290..f0de36f13a4 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -80,14 +80,22 @@ int irq_can_set_affinity(unsigned int irq) return 1; } -void -irq_set_thread_affinity(struct irq_desc *desc, const struct cpumask *cpumask) +/** + * irq_set_thread_affinity - Notify irq threads to adjust affinity + * @desc: irq descriptor which has affitnity changed + * + * We just set IRQTF_AFFINITY and delegate the affinity setting + * to the interrupt thread itself. We can not call + * set_cpus_allowed_ptr() here as we hold desc->lock and this + * code can be called from hard interrupt context. + */ +void irq_set_thread_affinity(struct irq_desc *desc) { struct irqaction *action = desc->action; while (action) { if (action->thread) - set_cpus_allowed_ptr(action->thread, cpumask); + set_bit(IRQTF_AFFINITY, &action->thread_flags); action = action->next; } } @@ -112,7 +120,7 @@ int irq_set_affinity(unsigned int irq, const struct cpumask *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); + irq_set_thread_affinity(desc); } } else { @@ -122,7 +130,7 @@ int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask) #else if (!desc->chip->set_affinity(irq, cpumask)) { cpumask_copy(desc->affinity, cpumask); - irq_set_thread_affinity(desc, cpumask); + irq_set_thread_affinity(desc); } #endif desc->status |= IRQ_AFFINITY_SET; @@ -176,7 +184,7 @@ int irq_select_affinity_usr(unsigned int irq) spin_lock_irqsave(&desc->lock, flags); ret = setup_affinity(irq, desc); if (!ret) - irq_set_thread_affinity(desc, desc->affinity); + irq_set_thread_affinity(desc); spin_unlock_irqrestore(&desc->lock, flags); return ret; @@ -444,6 +452,34 @@ static int irq_wait_for_interrupt(struct irqaction *action) } /* + * Check whether we need to change the affinity of the interrupt thread. + */ +static void +irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) +{ + cpumask_var_t mask; + + if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags)) + return; + + /* + * In case we are out of memory we set IRQTF_AFFINITY again and + * try again next time + */ + if (!alloc_cpumask_var(&mask, GFP_KERNEL)) { + set_bit(IRQTF_AFFINITY, &action->thread_flags); + return; + } + + spin_lock_irq(&desc->lock); + cpumask_copy(mask, desc->affinity); + spin_unlock_irq(&desc->lock); + + set_cpus_allowed_ptr(current, mask); + free_cpumask_var(mask); +} + +/* * Interrupt handler thread */ static int irq_thread(void *data) @@ -458,6 +494,8 @@ static int irq_thread(void *data) while (!irq_wait_for_interrupt(action)) { + irq_thread_check_affinity(desc, action); + atomic_inc(&desc->threads_active); spin_lock_irq(&desc->lock); |