diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2011-02-07 10:34:30 +0100 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2011-02-19 12:58:09 +0100 |
| commit | fe200ae48ef5c79bf7941fe8046ff9505c570ff6 (patch) | |
| tree | 767d2cf011437a266a655ce2ec39360cb85f7f28 /kernel/irq/chip.c | |
| parent | d05c65fff0ef672be75429266751f0e015b54d94 (diff) | |
| download | linux-fe200ae48ef5c79bf7941fe8046ff9505c570ff6.tar.bz2 | |
genirq: Mark polled irqs and defer the real handler
With the chip.end() function gone we might run into a situation where
a poll call runs and the real interrupt comes in, sees IRQ_INPROGRESS
and disables the line. That might be a perfect working one, which will
then be masked forever.
So mark them polled while the poll runs. When the real handler sees
IRQ_INPROGRESS it checks the poll flag and waits for the polling to
complete. Add the necessary amount of sanity checks to it to avoid
deadlocks.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'kernel/irq/chip.c')
| -rw-r--r-- | kernel/irq/chip.c | 26 |
1 files changed, 20 insertions, 6 deletions
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 622b55ac0e09..31258782742c 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -448,6 +448,13 @@ out_unlock: } EXPORT_SYMBOL_GPL(handle_nested_irq); +static bool irq_check_poll(struct irq_desc *desc) +{ + if (!(desc->status & IRQ_POLL_INPROGRESS)) + return false; + return irq_wait_for_poll(desc); +} + /** * handle_simple_irq - Simple and software-decoded IRQs. * @irq: the interrupt number @@ -469,7 +476,9 @@ handle_simple_irq(unsigned int irq, struct irq_desc *desc) raw_spin_lock(&desc->lock); if (unlikely(desc->status & IRQ_INPROGRESS)) - goto out_unlock; + if (!irq_check_poll(desc)) + goto out_unlock; + desc->status &= ~(IRQ_REPLAY | IRQ_WAITING); kstat_incr_irqs_this_cpu(irq, desc); @@ -510,7 +519,9 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc) mask_ack_irq(desc); if (unlikely(desc->status & IRQ_INPROGRESS)) - goto out_unlock; + if (!irq_check_poll(desc)) + goto out_unlock; + desc->status &= ~(IRQ_REPLAY | IRQ_WAITING); kstat_incr_irqs_this_cpu(irq, desc); @@ -558,7 +569,8 @@ handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc) raw_spin_lock(&desc->lock); if (unlikely(desc->status & IRQ_INPROGRESS)) - goto out; + if (!irq_check_poll(desc)) + goto out; desc->status &= ~(IRQ_REPLAY | IRQ_WAITING); kstat_incr_irqs_this_cpu(irq, desc); @@ -620,9 +632,11 @@ handle_edge_irq(unsigned int irq, struct irq_desc *desc) */ if (unlikely((desc->status & (IRQ_INPROGRESS | IRQ_DISABLED)) || !desc->action)) { - desc->status |= (IRQ_PENDING | IRQ_MASKED); - mask_ack_irq(desc); - goto out_unlock; + if (!irq_check_poll(desc)) { + desc->status |= (IRQ_PENDING | IRQ_MASKED); + mask_ack_irq(desc); + goto out_unlock; + } } kstat_incr_irqs_this_cpu(irq, desc); |