diff options
| author | Thomas Gleixner <tglx@linutronix.de> | 2012-02-07 17:58:03 +0100 |
|---|---|---|
| committer | Clark Williams <williams@redhat.com> | 2012-02-15 10:32:26 -0600 |
| commit | e16d188fb6a131d7ecd90bdfc50b2156e55c65e7 (patch) | |
| tree | 02385450c3cb8c89fc51fe76bc216b1c736fc4b1 /kernel/irq | |
| parent | 35c800b532180419eb268e4410eb299341f7d26b (diff) | |
genirq: Unmask oneshot irqs when thread was not woken
When the primary handler of an interrupt which is marked IRQ_ONESHOT
does not wake the thread (e.g. due to a spurious interrupt) then
nothing ever unmasks the interrupt line again. Handle it gracefully.
Reported-by: Lothar Wassmann <lw@karo-electronics.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'kernel/irq')
| -rw-r--r-- | kernel/irq/chip.c | 25 |
1 files changed, 23 insertions, 2 deletions
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index f7c543a801d9..b742edc0bdd4 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -330,6 +330,24 @@ out_unlock: } EXPORT_SYMBOL_GPL(handle_simple_irq); +/* + * Called unconditionally from handle_level_irq() and only for oneshot + * interrupts from handle_fasteoi_irq() + */ +static void cond_unmask_irq(struct irq_desc *desc) +{ + /* + * We need to unmask in the following cases: + * - Standard level irq (IRQF_ONESHOT is not set) + * - Oneshot irq which did not wake the thread (caused by a + * spurious interrupt or a primary handler handling it + * completely). + */ + if (!irqd_irq_disabled(&desc->irq_data) && + irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot) + unmask_irq(desc); +} + /** * handle_level_irq - Level type irq handler * @irq: the interrupt number @@ -362,8 +380,8 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc) handle_irq_event(desc); - if (!irqd_irq_disabled(&desc->irq_data) && !(desc->istate & IRQS_ONESHOT)) - unmask_irq(desc); + cond_unmask_irq(desc); + out_unlock: raw_spin_unlock(&desc->lock); } @@ -417,6 +435,9 @@ handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc) preflow_handler(desc); handle_irq_event(desc); + if (desc->istate & IRQS_ONESHOT) + cond_unmask_irq(desc); + out_eoi: desc->irq_data.chip->irq_eoi(&desc->irq_data); out_unlock: |