diff options
Diffstat (limited to 'kernel/irq/spurious.c')
| -rw-r--r-- | kernel/irq/spurious.c | 113 |
1 files changed, 111 insertions, 2 deletions
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c index ba039e827d58..7df9abd5ec86 100644 --- a/kernel/irq/spurious.c +++ b/kernel/irq/spurious.c @@ -11,6 +11,83 @@ #include <linux/kallsyms.h> #include <linux/interrupt.h> +static int irqfixup; + +/* + * Recovery handler for misrouted interrupts. + */ + +static int misrouted_irq(int irq, struct pt_regs *regs) +{ + int i; + irq_desc_t *desc; + int ok = 0; + int work = 0; /* Did we do work for a real IRQ */ + + for(i = 1; i < NR_IRQS; i++) { + struct irqaction *action; + + if (i == irq) /* Already tried */ + continue; + desc = &irq_desc[i]; + spin_lock(&desc->lock); + action = desc->action; + /* Already running on another processor */ + if (desc->status & IRQ_INPROGRESS) { + /* + * Already running: If it is shared get the other + * CPU to go looking for our mystery interrupt too + */ + if (desc->action && (desc->action->flags & SA_SHIRQ)) + desc->status |= IRQ_PENDING; + spin_unlock(&desc->lock); + continue; + } + /* Honour the normal IRQ locking */ + desc->status |= IRQ_INPROGRESS; + spin_unlock(&desc->lock); + while (action) { + /* Only shared IRQ handlers are safe to call */ + if (action->flags & SA_SHIRQ) { + if (action->handler(i, action->dev_id, regs) == + IRQ_HANDLED) + ok = 1; + } + action = action->next; + } + local_irq_disable(); + /* Now clean up the flags */ + spin_lock(&desc->lock); + action = desc->action; + + /* + * While we were looking for a fixup someone queued a real + * IRQ clashing with our walk + */ + + while ((desc->status & IRQ_PENDING) && action) { + /* + * Perform real IRQ processing for the IRQ we deferred + */ + work = 1; + spin_unlock(&desc->lock); + handle_IRQ_event(i, regs, action); + spin_lock(&desc->lock); + desc->status &= ~IRQ_PENDING; + } + desc->status &= ~IRQ_INPROGRESS; + /* + * If we did actual work for the real IRQ line we must let the + * IRQ controller clean up too + */ + if(work) + desc->handler->end(i); + spin_unlock(&desc->lock); + } + /* So the caller can adjust the irq error counts */ + return ok; +} + /* * If 99,900 of the previous 100,000 interrupts have not been handled * then assume that the IRQ is stuck in some manner. Drop a diagnostic @@ -31,7 +108,8 @@ __report_bad_irq(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret) printk(KERN_ERR "irq event %d: bogus return value %x\n", irq, action_ret); } else { - printk(KERN_ERR "irq %d: nobody cared!\n", irq); + printk(KERN_ERR "irq %d: nobody cared (try booting with " + "the \"irqpoll\" option)\n", irq); } dump_stack(); printk(KERN_ERR "handlers:\n"); @@ -55,7 +133,8 @@ static void report_bad_irq(unsigned int irq, irq_desc_t *desc, irqreturn_t actio } } -void note_interrupt(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret) +void note_interrupt(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret, + struct pt_regs *regs) { if (action_ret != IRQ_HANDLED) { desc->irqs_unhandled++; @@ -63,6 +142,15 @@ void note_interrupt(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret) report_bad_irq(irq, desc, action_ret); } + if (unlikely(irqfixup)) { + /* Don't punish working computers */ + if ((irqfixup == 2 && irq == 0) || action_ret == IRQ_NONE) { + int ok = misrouted_irq(irq, regs); + if (action_ret == IRQ_NONE) + desc->irqs_unhandled -= ok; + } + } + desc->irq_count++; if (desc->irq_count < 100000) return; @@ -94,3 +182,24 @@ int __init noirqdebug_setup(char *str) __setup("noirqdebug", noirqdebug_setup); +static int __init irqfixup_setup(char *str) +{ + irqfixup = 1; + printk(KERN_WARNING "Misrouted IRQ fixup support enabled.\n"); + printk(KERN_WARNING "This may impact system performance.\n"); + return 1; +} + +__setup("irqfixup", irqfixup_setup); + +static int __init irqpoll_setup(char *str) +{ + irqfixup = 2; + printk(KERN_WARNING "Misrouted IRQ fixup and polling support " + "enabled\n"); + printk(KERN_WARNING "This may significantly impact system " + "performance\n"); + return 1; +} + +__setup("irqpoll", irqpoll_setup); |