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>


--- linux-2.6.11/fs/aio.c.orig	2005-03-24 15:37:27.000000000 -0800
+++ linux-2.6.11/fs/aio.c	2005-03-24 16:05:24.000000000 -0800
@@ -984,7 +984,8 @@ int fastcall aio_complete(struct kiocb *
 
 	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;