Commit ccdea2f8 authored Dec 06, 2006 by Ralf Baechle Committed by Linus Torvalds Dec 07, 2006

[PATCH] futex: remove unneeded barrier



When disassembling a kernel I found around over 90 sync Instructions from
mb, rmb and wmb calls in the kernel and only few of those make any sense to
me.  So here's the first one - I think the wmb() in kernel/futex.c is not
needed on uniprocessors so should become an smb_wmb().

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent e384bd16

kernel/futex.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -552,7 +552,7 @@ static void wake_futex(struct futex_q *q)
		* at the end of wake_up_all() does not prevent this store from
		* moving.
		*/
		wmb();
		smp_wmb();
		q->lock_ptr = NULL;
		}