[PATCH 3/3] irq: Comment on the use of inline stack for ksoftirq

Frederic Weisbecker
2013-09-05T15:33:41Z

Ksoftirqd shouldn't need softirq stack since it's executing
in a kernel thread with a callstack that is only beginning at
this stage.

Lets comment about that for clarity.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@au1.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@au1.ibm.com>
Cc: James Hogan <james.hogan@imgtec.com>
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: Helge Deller <deller@gmx.de>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Andrew Morton <akpm@linux-foundation.org>
---
kernel/softirq.c | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/kernel/softirq.c b/kernel/softirq.c
index 657e047..1de0322 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -759,6 +759,7 @@ static void run_ksoftirqd(unsigned int cpu)
{
local_irq_disable();
if (local_softirq_pending()) {
+ /* No need to use softirq stack here */
__do_softirq();
rcu_note_context_switch(cpu);
local_irq_enable();
--
1.7.5.4