@@ -791,9 +791,19 @@ static irqreturn_t irq_forced_secondary_handler(int irq, void *dev_id)
static int irq_wait_for_interrupt(struct irqaction *action)
{
- set_current_state(TASK_INTERRUPTIBLE);
+ for (;;) {
+ set_current_state(TASK_INTERRUPTIBLE);
- while (!kthread_should_stop()) {
+ if (kthread_should_stop()) {
+ /* may need to run one last time */
+ if (test_and_clear_bit(IRQTF_RUNTHREAD,
+ &action->thread_flags)) {
+ __set_current_state(TASK_RUNNING);
+ return 0;
+ }
+ __set_current_state(TASK_RUNNING);
+ return -1;
+ }
if (test_and_clear_bit(IRQTF_RUNTHREAD,
&action->thread_flags)) {
@@ -801,10 +811,7 @@ static int irq_wait_for_interrupt(struct irqaction *action)
return 0;
}
schedule();
- set_current_state(TASK_INTERRUPTIBLE);
}
- __set_current_state(TASK_RUNNING);
- return -1;
}
/*
@@ -1029,7 +1036,7 @@ static int irq_thread(void *data)
/*
* This is the regular exit path. __free_irq() is stopping the
* thread via kthread_stop() after calling
- * synchronize_irq(). So neither IRQTF_RUNTHREAD nor the
+ * synchronize_hardirq(). So neither IRQTF_RUNTHREAD nor the
* oneshot mask bit can be set.
*/
task_work_cancel(current, irq_thread_dtor);
@@ -1253,7 +1260,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
/*
* Protects against a concurrent __free_irq() call which might wait
- * for synchronize_irq() to complete without holding the optional
+ * for synchronize_hardirq() to complete without holding the optional
* chip bus lock and desc->lock. Also protects against handing out
* a recycled oneshot thread_mask bit while it's still in use by
* its previous owner.
@@ -1610,11 +1617,11 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
/*
* Drop bus_lock here so the changes which were done in the chip
* callbacks above are synced out to the irq chips which hang
- * behind a slow bus (I2C, SPI) before calling synchronize_irq().
+ * behind a slow bus (I2C, SPI) before calling synchronize_hardirq().
*
* Aside of that the bus_lock can also be taken from the threaded
* handler in irq_finalize_oneshot() which results in a deadlock
- * because synchronize_irq() would wait forever for the thread to
+ * because kthread_stop() would wait forever for the thread to
* complete, which is blocked on the bus lock.
*
* The still held desc->request_mutex() protects against a
@@ -1626,7 +1633,7 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
unregister_handler_proc(irq, action);
/* Make sure it's not being used on another CPU: */
- synchronize_irq(irq);
+ synchronize_hardirq(irq);
#ifdef CONFIG_DEBUG_SHIRQ
/*
@@ -1644,6 +1651,12 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
}
#endif
+ /*
+ * The action has already been removed above, but the thread writes
+ * its oneshot mask bit when it completes. Though request_mutex is
+ * held across this which prevents __setup_irq() from handing out
+ * the same bit to a newly requested action.
+ */
if (action->thread) {
kthread_stop(action->thread);
put_task_struct(action->thread);