diff options
| -rw-r--r-- | include/linux/irq.h | 13 | ||||
| -rw-r--r-- | kernel/irq/chip.c | 16 | ||||
| -rw-r--r-- | kernel/irq/debugfs.c | 2 |
3 files changed, 30 insertions, 1 deletions
diff --git a/include/linux/irq.h b/include/linux/irq.h index d9c86db69982..d8a6fdce9373 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -223,6 +223,8 @@ struct irq_data { * irq_chip::irq_set_affinity() when deactivated. * IRQD_IRQ_ENABLED_ON_SUSPEND - Interrupt is enabled on suspend by irq pm if * irqchip have flag IRQCHIP_ENABLE_WAKEUP_ON_SUSPEND set. + * IRQD_RESEND_WHEN_IN_PROGRESS - Interrupt may fire when already in progress in which + * case it must be resent at the next available opportunity. */ enum { IRQD_TRIGGER_MASK = 0xf, @@ -249,6 +251,7 @@ enum { IRQD_HANDLE_ENFORCE_IRQCTX = BIT(28), IRQD_AFFINITY_ON_ACTIVATE = BIT(29), IRQD_IRQ_ENABLED_ON_SUSPEND = BIT(30), + IRQD_RESEND_WHEN_IN_PROGRESS = BIT(31), }; #define __irqd_to_state(d) ACCESS_PRIVATE((d)->common, state_use_accessors) @@ -448,6 +451,16 @@ static inline bool irqd_affinity_on_activate(struct irq_data *d) return __irqd_to_state(d) & IRQD_AFFINITY_ON_ACTIVATE; } +static inline void irqd_set_resend_when_in_progress(struct irq_data *d) +{ + __irqd_to_state(d) |= IRQD_RESEND_WHEN_IN_PROGRESS; +} + +static inline bool irqd_needs_resend_when_in_progress(struct irq_data *d) +{ + return __irqd_to_state(d) & IRQD_RESEND_WHEN_IN_PROGRESS; +} + #undef __irqd_to_state static inline irq_hw_number_t irqd_to_hwirq(struct irq_data *d) diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 49e7bc871fec..57cd8f475302 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -692,8 +692,16 @@ void handle_fasteoi_irq(struct irq_desc *desc) raw_spin_lock(&desc->lock); - if (!irq_may_run(desc)) + /* + * When an affinity change races with IRQ handling, the next interrupt + * can arrive on the new CPU before the original CPU has completed + * handling the previous one - it may need to be resent. + */ + if (!irq_may_run(desc)) { + if (irqd_needs_resend_when_in_progress(&desc->irq_data)) + desc->istate |= IRQS_PENDING; goto out; + } desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); @@ -715,6 +723,12 @@ void handle_fasteoi_irq(struct irq_desc *desc) cond_unmask_eoi_irq(desc, chip); + /* + * When the race described above happens this will resend the interrupt. + */ + if (unlikely(desc->istate & IRQS_PENDING)) + check_irq_resend(desc, false); + raw_spin_unlock(&desc->lock); return; out: diff --git a/kernel/irq/debugfs.c b/kernel/irq/debugfs.c index bbcaac64038e..5971a66be034 100644 --- a/kernel/irq/debugfs.c +++ b/kernel/irq/debugfs.c @@ -133,6 +133,8 @@ static const struct irq_bit_descr irqdata_states[] = { BIT_MASK_DESCR(IRQD_HANDLE_ENFORCE_IRQCTX), BIT_MASK_DESCR(IRQD_IRQ_ENABLED_ON_SUSPEND), + + BIT_MASK_DESCR(IRQD_RESEND_WHEN_IN_PROGRESS), }; static const struct irq_bit_descr irqdesc_states[] = { |