diff options
| -rw-r--r-- | include/linux/hardirq.h | 2 | ||||
| -rw-r--r-- | include/linux/interrupt.h | 1 | ||||
| -rw-r--r-- | include/linux/irqflags.h | 43 | ||||
| -rw-r--r-- | kernel/irq/manage.c | 36 |
4 files changed, 58 insertions, 24 deletions
diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h index cba442ec3c66..f4af03404b97 100644 --- a/include/linux/hardirq.h +++ b/include/linux/hardirq.h @@ -9,7 +9,7 @@ extern void synchronize_irq(unsigned int irq); -extern void synchronize_hardirq(unsigned int irq); +extern bool synchronize_hardirq(unsigned int irq); #if defined(CONFIG_TINY_RCU) diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index d9b05b5bf8c7..3bb01b9a379c 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -184,6 +184,7 @@ extern void devm_free_irq(struct device *dev, unsigned int irq, void *dev_id); #endif extern void disable_irq_nosync(unsigned int irq); +extern bool disable_hardirq(unsigned int irq); extern void disable_irq(unsigned int irq); extern void disable_percpu_irq(unsigned int irq); extern void enable_irq(unsigned int irq); diff --git a/include/linux/irqflags.h b/include/linux/irqflags.h index d176d658fe25..5dd1272d1ab2 100644 --- a/include/linux/irqflags.h +++ b/include/linux/irqflags.h @@ -85,7 +85,7 @@ * The local_irq_*() APIs are equal to the raw_local_irq*() * if !TRACE_IRQFLAGS. */ -#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT +#ifdef CONFIG_TRACE_IRQFLAGS #define local_irq_enable() \ do { trace_hardirqs_on(); raw_local_irq_enable(); } while (0) #define local_irq_disable() \ @@ -107,22 +107,6 @@ raw_local_irq_restore(flags); \ } \ } while (0) -#define local_save_flags(flags) \ - do { \ - raw_local_save_flags(flags); \ - } while (0) - -#define irqs_disabled_flags(flags) \ - ({ \ - raw_irqs_disabled_flags(flags); \ - }) - -#define irqs_disabled() \ - ({ \ - unsigned long _flags; \ - raw_local_save_flags(_flags); \ - raw_irqs_disabled_flags(_flags); \ - }) #define safe_halt() \ do { \ @@ -131,7 +115,7 @@ } while (0) -#else /* !CONFIG_TRACE_IRQFLAGS_SUPPORT */ +#else /* !CONFIG_TRACE_IRQFLAGS */ #define local_irq_enable() do { raw_local_irq_enable(); } while (0) #define local_irq_disable() do { raw_local_irq_disable(); } while (0) @@ -140,11 +124,28 @@ raw_local_irq_save(flags); \ } while (0) #define local_irq_restore(flags) do { raw_local_irq_restore(flags); } while (0) -#define local_save_flags(flags) do { raw_local_save_flags(flags); } while (0) -#define irqs_disabled() (raw_irqs_disabled()) -#define irqs_disabled_flags(flags) (raw_irqs_disabled_flags(flags)) #define safe_halt() do { raw_safe_halt(); } while (0) +#endif /* CONFIG_TRACE_IRQFLAGS */ + +#define local_save_flags(flags) raw_local_save_flags(flags) + +/* + * Some architectures don't define arch_irqs_disabled(), so even if either + * definition would be fine we need to use different ones for the time being + * to avoid build issues. + */ +#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT +#define irqs_disabled() \ + ({ \ + unsigned long _flags; \ + raw_local_save_flags(_flags); \ + raw_irqs_disabled_flags(_flags); \ + }) +#else /* !CONFIG_TRACE_IRQFLAGS_SUPPORT */ +#define irqs_disabled() raw_irqs_disabled() #endif /* CONFIG_TRACE_IRQFLAGS_SUPPORT */ +#define irqs_disabled_flags(flags) raw_irqs_disabled_flags(flags) + #endif diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index 196a06fbc122..03329c2287eb 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -68,14 +68,20 @@ static void __synchronize_hardirq(struct irq_desc *desc) * Do not use this for shutdown scenarios where you must be sure * that all parts (hardirq and threaded handler) have completed. * + * Returns: false if a threaded handler is active. + * * This function may be called - with care - from IRQ context. */ -void synchronize_hardirq(unsigned int irq) +bool synchronize_hardirq(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); - if (desc) + if (desc) { __synchronize_hardirq(desc); + return !atomic_read(&desc->threads_active); + } + + return true; } EXPORT_SYMBOL(synchronize_hardirq); @@ -440,6 +446,32 @@ void disable_irq(unsigned int irq) } EXPORT_SYMBOL(disable_irq); +/** + * disable_hardirq - disables an irq and waits for hardirq completion + * @irq: Interrupt to disable + * + * Disable the selected interrupt line. Enables and Disables are + * nested. + * This function waits for any pending hard IRQ handlers for this + * interrupt to complete before returning. If you use this function while + * holding a resource the hard IRQ handler may need you will deadlock. + * + * When used to optimistically disable an interrupt from atomic context + * the return value must be checked. + * + * Returns: false if a threaded handler is active. + * + * This function may be called - with care - from IRQ context. + */ +bool disable_hardirq(unsigned int irq) +{ + if (!__disable_irq_nosync(irq)) + return synchronize_hardirq(irq); + + return false; +} +EXPORT_SYMBOL_GPL(disable_hardirq); + void __enable_irq(struct irq_desc *desc, unsigned int irq) { switch (desc->depth) { |