diff options
| -rw-r--r-- | kernel/irq/chip.c | 41 |
1 files changed, 39 insertions, 2 deletions
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index 11ecf6c78c01..624106e886ad 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -476,11 +476,14 @@ static bool irq_wait_on_inprogress(struct irq_desc *desc) static bool irq_can_handle_pm(struct irq_desc *desc) { + struct irq_data *irqd = &desc->irq_data; + const struct cpumask *aff; + /* * If the interrupt is not in progress and is not an armed * wakeup interrupt, proceed. */ - if (!irqd_has_set(&desc->irq_data, IRQD_IRQ_INPROGRESS | IRQD_WAKEUP_ARMED)) + if (!irqd_has_set(irqd, IRQD_IRQ_INPROGRESS | IRQD_WAKEUP_ARMED)) return true; /* @@ -501,7 +504,41 @@ static bool irq_can_handle_pm(struct irq_desc *desc) return false; return irq_wait_on_inprogress(desc); } - return false; + + /* The below works only for single target interrupts */ + if (!IS_ENABLED(CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK) || + !irqd_is_single_target(irqd) || desc->handle_irq != handle_edge_irq) + return false; + + /* + * If the interrupt affinity was moved to this CPU and the + * interrupt is currently handled on the previous target CPU, then + * busy wait for INPROGRESS to be cleared. Otherwise for edge type + * interrupts the handler might get stuck on the previous target: + * + * CPU 0 CPU 1 (new target) + * handle_edge_irq() + * repeat: + * handle_event() handle_edge_irq() + * if (INPROGESS) { + * set(PENDING); + * mask(); + * return; + * } + * if (PENDING) { + * clear(PENDING); + * unmask(); + * goto repeat; + * } + * + * This happens when the device raises interrupts with a high rate + * and always before handle_event() completes and the CPU0 handler + * can clear INPROGRESS. This has been observed in virtual machines. + */ + aff = irq_data_get_effective_affinity_mask(irqd); + if (cpumask_first(aff) != smp_processor_id()) + return false; + return irq_wait_on_inprogress(desc); } static inline bool irq_can_handle_actions(struct irq_desc *desc) |