Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758839AbaDBPTS (ORCPT ); Wed, 2 Apr 2014 11:19:18 -0400 Received: from mail-pb0-f52.google.com ([209.85.160.52]:60662 "EHLO mail-pb0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758337AbaDBPTQ (ORCPT ); Wed, 2 Apr 2014 11:19:16 -0400 From: Jianyu Zhan To: axboe@kernel.dk Cc: hch@lst.de, jack@suse.cz, viro@zeniv.linux.org.uk, kmo@daterainc.com, namjae.jeon@samsung.com, nasa4836@gmail.com, linux-kernel@vger.kernel.org Subject: [PATCH] blkdev: use an efficient way to check merge flags Date: Wed, 2 Apr 2014 23:19:06 +0800 Message-Id: <1396451946-13924-1-git-send-email-nasa4836@gmail.com> X-Mailer: git-send-email 1.9.0.GIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org A bitwise flag comparison could be done using a more efficient bit-ops way. Signed-off-by: Jianyu Zhan --- include/linux/blkdev.h | 13 +++---------- 1 file changed, 3 insertions(+), 10 deletions(-) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 1e1fa3f..adfa40a 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -655,16 +655,9 @@ static inline bool rq_mergeable(struct request *rq) static inline bool blk_check_merge_flags(unsigned int flags1, unsigned int flags2) { - if ((flags1 & REQ_DISCARD) != (flags2 & REQ_DISCARD)) - return false; - - if ((flags1 & REQ_SECURE) != (flags2 & REQ_SECURE)) - return false; - - if ((flags1 & REQ_WRITE_SAME) != (flags2 & REQ_WRITE_SAME)) - return false; - - return true; + return (flags1 & (REQ_DISCARD | REQ_SECURE | REQ_WRITE_SAME)) ^ + (flags2 & (REQ_DISCARD | REQ_SECURE | REQ_WRITE_SAME)) + == 0; } static inline bool blk_write_same_mergeable(struct bio *a, struct bio *b) -- 1.9.0.GIT -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/