diff options
| -rw-r--r-- | kernel/irq/internals.h | 4 | ||||
| -rw-r--r-- | kernel/irq/manage.c | 75 |
2 files changed, 60 insertions, 19 deletions
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index 9c957f8b1198..3a948f41ab00 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -97,6 +97,10 @@ static inline void irq_mark_irq(unsigned int irq) { } extern void irq_mark_irq(unsigned int irq); #endif +extern int __irq_get_irqchip_state(struct irq_data *data, + enum irqchip_irq_state which, + bool *state); + extern void init_kstat_irqs(struct irq_desc *desc, int node, int nr); irqreturn_t __handle_irq_event_percpu(struct irq_desc *desc, unsigned int *flags); diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 44fc505815d6..fad61986f35c 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -35,8 +35,9 @@ static int __init setup_forced_irqthreads(char *arg) early_param("threadirqs", setup_forced_irqthreads); #endif -static void __synchronize_hardirq(struct irq_desc *desc) +static void __synchronize_hardirq(struct irq_desc *desc, bool sync_chip) { + struct irq_data *irqd = irq_desc_get_irq_data(desc); bool inprogress; do { @@ -52,6 +53,20 @@ static void __synchronize_hardirq(struct irq_desc *desc) /* Ok, that indicated we're done: double-check carefully. */ raw_spin_lock_irqsave(&desc->lock, flags); inprogress = irqd_irq_inprogress(&desc->irq_data); + + /* + * If requested and supported, check at the chip whether it + * is in flight at the hardware level, i.e. already pending + * in a CPU and waiting for service and acknowledge. + */ + if (!inprogress && sync_chip) { + /* + * Ignore the return code. inprogress is only updated + * when the chip supports it. + */ + __irq_get_irqchip_state(irqd, IRQCHIP_STATE_ACTIVE, + &inprogress); + } raw_spin_unlock_irqrestore(&desc->lock, flags); /* Oops, that failed? */ @@ -74,13 +89,18 @@ static void __synchronize_hardirq(struct irq_desc *desc) * Returns: false if a threaded handler is active. * * This function may be called - with care - from IRQ context. + * + * It does not check whether there is an interrupt in flight at the + * hardware level, but not serviced yet, as this might deadlock when + * called with interrupts disabled and the target CPU of the interrupt + * is the current CPU. */ bool synchronize_hardirq(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); if (desc) { - __synchronize_hardirq(desc); + __synchronize_hardirq(desc, false); return !atomic_read(&desc->threads_active); } @@ -98,13 +118,17 @@ EXPORT_SYMBOL(synchronize_hardirq); * * Can only be called from preemptible code as it might sleep when * an interrupt thread is associated to @irq. + * + * It optionally makes sure (when the irq chip supports that method) + * that the interrupt is not pending in any CPU and waiting for + * service. */ void synchronize_irq(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); if (desc) { - __synchronize_hardirq(desc); + __synchronize_hardirq(desc, true); /* * We made sure that no hardirq handler is * running. Now verify that no threaded handlers are @@ -1730,8 +1754,12 @@ static struct irqaction *__free_irq(struct irq_desc *desc, void *dev_id) unregister_handler_proc(irq, action); - /* Make sure it's not being used on another CPU: */ - synchronize_hardirq(irq); + /* + * Make sure it's not being used on another CPU and if the chip + * supports it also make sure that there is no (not yet serviced) + * interrupt in flight at the hardware level. + */ + __synchronize_hardirq(desc, true); #ifdef CONFIG_DEBUG_SHIRQ /* @@ -2589,6 +2617,28 @@ out: irq_put_desc_unlock(desc, flags); } +int __irq_get_irqchip_state(struct irq_data *data, enum irqchip_irq_state which, + bool *state) +{ + struct irq_chip *chip; + int err = -EINVAL; + + do { + chip = irq_data_get_irq_chip(data); + if (chip->irq_get_irqchip_state) + break; +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY + data = data->parent_data; +#else + data = NULL; +#endif + } while (data); + + if (data) + err = chip->irq_get_irqchip_state(data, which, state); + return err; +} + /** * irq_get_irqchip_state - returns the irqchip state of a interrupt. * @irq: Interrupt line that is forwarded to a VM @@ -2607,7 +2657,6 @@ int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which, { struct irq_desc *desc; struct irq_data *data; - struct irq_chip *chip; unsigned long flags; int err = -EINVAL; @@ -2617,19 +2666,7 @@ int irq_get_irqchip_state(unsigned int irq, enum irqchip_irq_state which, data = irq_desc_get_irq_data(desc); - do { - chip = irq_data_get_irq_chip(data); - if (chip->irq_get_irqchip_state) - break; -#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY - data = data->parent_data; -#else - data = NULL; -#endif - } while (data); - - if (data) - err = chip->irq_get_irqchip_state(data, which, state); + err = __irq_get_irqchip_state(data, which, state); irq_put_desc_busunlock(desc, flags); return err; |