From: Ming Lei <tom.leiming@gmail.com>
Date: Sat, 19 Apr 2014 10:00:18 +0000 (+0800)
Subject: blk-mq: user (1 << order) to implement order_to_size()
X-Git-Tag: v3.16-rc1~30^2~49^2~66
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4ca085009f447abc1c818f8802e908e9afdd77fa;p=platform%2Fkernel%2Flinux-stable.git

blk-mq: user (1 << order) to implement order_to_size()

Cc: Jörg-Volker Peetz <jvpeetz@web.de>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
---

diff --git a/block/blk-mq.c b/block/blk-mq.c
index c277797..3a560a4 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1130,12 +1130,7 @@ static void blk_mq_free_rq_map(struct blk_mq_tag_set *set,
 
 static size_t order_to_size(unsigned int order)
 {
-	size_t ret = PAGE_SIZE;
-
-	while (order--)
-		ret *= 2;
-
-	return ret;
+	return (size_t)PAGE_SIZE << order;
 }
 
 static struct blk_mq_tags *blk_mq_init_rq_map(struct blk_mq_tag_set *set,