From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx142.postini.com [74.125.245.142]) by kanga.kvack.org (Postfix) with SMTP id 4E6646B007E for ; Tue, 20 Mar 2012 06:16:25 -0400 (EDT) From: Lai Jiangshan Subject: [RFC PATCH 1/6] kenrel.h: add ALIGN_OF_LAST_BIT() Date: Tue, 20 Mar 2012 18:21:19 +0800 Message-Id: <1332238884-6237-2-git-send-email-laijs@cn.fujitsu.com> In-Reply-To: <1332238884-6237-1-git-send-email-laijs@cn.fujitsu.com> References: <1332238884-6237-1-git-send-email-laijs@cn.fujitsu.com> Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Lameter , Pekka Enberg , Matt Mackall , Tejun Heo , Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Lai Jiangshan Get the biggest 2**y that x % (2**y) == 0 for the align value. Signed-off-by: Lai Jiangshan --- include/linux/kernel.h | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 5113462..2c439dc 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -44,6 +44,8 @@ #define PTR_ALIGN(p, a) ((typeof(p))ALIGN((unsigned long)(p), (a))) #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0) +#define ALIGN_OF_LAST_BIT(x) ((((x)^((x) - 1))>>1) + 1) + #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + __must_be_array(arr)) /* -- 1.7.4.4 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org