Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932221AbaLBIcy (ORCPT ); Tue, 2 Dec 2014 03:32:54 -0500 Received: from mail.windriver.com ([147.11.1.11]:62110 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751458AbaLBIcx (ORCPT ); Tue, 2 Dec 2014 03:32:53 -0500 Message-ID: <547D790E.3070803@windriver.com> Date: Tue, 2 Dec 2014 16:32:14 +0800 From: zhangxiao User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130330 Thunderbird/17.0.5 MIME-Version: 1.0 To: CC: , Subject: The DM_BUFIO_HASH_BITS is defined as 20, any plan to make it flexible? Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [128.224.163.132] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi NeilBrown, See drivers/md/dm-bufio.c as below: 50 /* 51 * Buffer hash 52 */ 53 #define DM_BUFIO_HASH_BITS 20 54 #define DM_BUFIO_HASH(block) \ 55 ((((block) >> DM_BUFIO_HASH_BITS) ^ (block)) & \ 56 ((1 << DM_BUFIO_HASH_BITS) - 1)) "drivers/md/dm-bufio.c" 1854L, 45375C DM_BUFIO_HASH_BITS was defined as 20 and it maybe not fit for some use case with limited resources. Do we have any plan to make it more flexible? Like module parameter or something else? Thanks Xiao -- 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/