[RESEND PATCH 1/3] genirq: Minor readablity improvement inirq_wake_thread()

From: Alexander Gordeev
Date: Wed Mar 21 2012 - 12:22:23 EST


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 fix just makes it more visible in the
source code.

Signed-off-by: Alexander Gordeev <agordeev@xxxxxxxxxx>
---
kernel/irq/handle.c | 16 ++++++++++------
1 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index 6ff84e6..bdb1803 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -54,14 +54,18 @@ static void warn_no_thread(unsigned int irq, struct irqaction *action)
static void irq_wake_thread(struct irq_desc *desc, struct irqaction *action)
{
/*
- * Wake up the handler thread for this action. In case the
- * thread crashed and was killed we just pretend that we
- * handled the interrupt. The hardirq handler has disabled the
- * device interrupt, so no irq storm is lurking. If the
+ * In case the thread crashed and was killed we just pretend that
+ * we handled the interrupt. The hardirq handler has disabled the
+ * device interrupt, so no irq storm is lurking.
+ */
+ if (action->thread->flags & PF_EXITING)
+ return;
+
+ /*
+ * Wake up the handler thread for this action. If the
* RUNTHREAD bit is already set, nothing to do.
*/
- if ((action->thread->flags & PF_EXITING) ||
- test_and_set_bit(IRQTF_RUNTHREAD, &action->thread_flags))
+ if (test_and_set_bit(IRQTF_RUNTHREAD, &action->thread_flags))
return;

/*
--
1.7.7.6

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