Commit 4bf69b2a authored May 01, 2005 by Ken Chen Committed by Linus Torvalds May 01, 2005

[PATCH] aio: ring wrapping simplification

Since the tail pointer in aio_ring structure never wrap ring size more than
once, so a simple compare is sufficient to wrap the index around.  This avoid
a more expensive mod operation.

Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Cc: Suparna Bhattacharya <suparna@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent 212079cf

fs/aio.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -978,7 +978,8 @@ int fastcall aio_complete(struct kiocb *iocb, long res, long res2)

		tail = info->tail;
		event = aio_ring_event(info, tail, KM_IRQ0);
		tail = (tail + 1) % info->nr;
		if (++tail >= info->nr)
		tail = 0;

		event->obj = (u64)(unsigned long)iocb->ki_obj.user;
		event->data = iocb->ki_user_data;

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