exit_irq_thread() clears IRQTF_RUNTHREAD flag and drops the thread's bit in desc->threads_oneshot then. The bit must not be set again in between and it does not, since irq_wake_thread() sees PF_EXITING flag first and returns. Due to above the order or checking PF_EXITING and IRQTF_RUNTHREAD flags in irq_wake_thread() is important. This change just makes it more visible in the source code.
Unified · Split
| @@ -54,14 +54,18 @@ static void warn_no_thread(unsigned int irq, struct irqaction *action) · 53 unmodified lines | ||
| 54 | 54 | static void irq_wake_thread(struct irq_desc *desc, struct irqaction *action) |
| 55 | 55 | { |
| 56 | 56 | /* |
| 57 | − * Wake up the handler thread for this action. In case the | |
| 58 | − * thread crashed and was killed we just pretend that we | |
| 59 | − * handled the interrupt. The hardirq handler has disabled the | |
| 60 | − * device interrupt, so no irq storm is lurking. If the | |
| 57 | + * In case the thread crashed and was killed we just pretend that | |
| 58 | + * we handled the interrupt. The hardirq handler has disabled the | |
| 59 | + * device interrupt, so no irq storm is lurking. | |
| 60 | + */ | |
| 61 | + if (action->thread->flags & PF_EXITING) | |
| 62 | + return; | |
| 63 | + | |
| 64 | + /* | |
| 65 | + * Wake up the handler thread for this action. If the | |
| 61 | 66 | * RUNTHREAD bit is already set, nothing to do. |
| 62 | 67 | */ |
| 63 | − if ((action->thread->flags & PF_EXITING) || | |
| 64 | − test_and_set_bit(IRQTF_RUNTHREAD, &action->thread_flags)) | |
| 68 | + if (test_and_set_bit(IRQTF_RUNTHREAD, &action->thread_flags)) | |
| 65 | 69 | return; |
| 66 | 70 | |
| 67 | 71 | /* |