irq: Optimize call to softirq on hardirq exit

Before processing softirqs on hardirq exit, we already
do the check for pending softirqs while hardirqs are
guaranteed to be disabled.

So we can take a shortcut and safely jump to the arch
specific implementation directly.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
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>

diff --git a/kernel/softirq.c b/kernel/softirq.c
index 26ee72725d29e986d69c5d76010abe126041807c..17c5cd2e3dae8e100a21845627fedec62803b54d 100644 (file)
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -335,7 +335,7 @@ static inline void invoke_softirq(void)
                 * in its own stack to prevent from any overrun on top
                 * of a potentially deep task stack.
                 */
-               do_softirq();
+               do_softirq_own_stack();
        } else {
                wakeup_softirqd();
        }