From mboxrd@z Thu Jan 1 00:00:00 1970 From: xiyou.wangcong@gmail.com (Cong Wang) Date: Wed, 07 Mar 2012 12:55:37 +0800 Subject: [PATCH v3] MM: CMA: add a simple kernel module as the helper to test CMA In-Reply-To: References: <1331090098-25097-1-git-send-email-Barry.Song@csr.com> <4F56E0AC.8070501@gmail.com> Message-ID: <4F56EA49.8070808@gmail.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 03/07/2012 12:49 PM, Barry Song wrote: > 2012/3/7 Cong Wang: >> On 03/07/2012 11:14 AM, Barry Song wrote: >>> >>> From: Barry Song >>> >>> Any write request to /dev/cma_test will let the module to allocate memory >>> from >>> CMA, for example: >>> >>> 1st time >>> $ echo 1024> /dev/cma_test >>> will require cma_test to request 1MB(1024KB) >>> 2nd time >>> $ echo 2048> /dev/cma_test >>> will require cma_test to request 2MB(2048KB) >>> >>> Any read request to /dev/cma_test will let the module to free the 1st >>> valid >>> memory from CMA, for example: >>> >>> 1st time >>> $ cat /dev/cma_test >>> will require cma_test to free the 1MB allocated in the first write request >>> 2nd time >>> $ cat /dev/cma_test >>> will require cma_test to free the 2MB allocated in the second write >>> request >> >> >> Any reason why using /dev not /proc or /sys? > > pls note it is just a test module to verify CMA at runtime. it is not > important either it is /dev, it is /proc or it is /sys. Why not important? You want it to be merged, don't you? > > any way to make things easier, we take that way. > Why /dev interface is easier than /proc and /sys? Confused, actually I think /proc or /sys should be easier... From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759480Ab2CGE4L (ORCPT ); Tue, 6 Mar 2012 23:56:11 -0500 Received: from mail-tul01m020-f174.google.com ([209.85.214.174]:51750 "EHLO mail-tul01m020-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759263Ab2CGEzx (ORCPT ); Tue, 6 Mar 2012 23:55:53 -0500 Message-ID: <4F56EA49.8070808@gmail.com> Date: Wed, 07 Mar 2012 12:55:37 +0800 From: Cong Wang User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.1) Gecko/20120216 Thunderbird/10.0.1 MIME-Version: 1.0 To: Barry Song <21cnbao@gmail.com> CC: Barry Song , linux-kernel@vger.kernel.org, workgroup.linux@csr.com, mina86@mina86.com, Barry Song , linux-arm-kernel@lists.infradead.org, m.szyprowski@samsung.com Subject: Re: [PATCH v3] MM: CMA: add a simple kernel module as the helper to test CMA References: <1331090098-25097-1-git-send-email-Barry.Song@csr.com> <4F56E0AC.8070501@gmail.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/07/2012 12:49 PM, Barry Song wrote: > 2012/3/7 Cong Wang: >> On 03/07/2012 11:14 AM, Barry Song wrote: >>> >>> From: Barry Song >>> >>> Any write request to /dev/cma_test will let the module to allocate memory >>> from >>> CMA, for example: >>> >>> 1st time >>> $ echo 1024> /dev/cma_test >>> will require cma_test to request 1MB(1024KB) >>> 2nd time >>> $ echo 2048> /dev/cma_test >>> will require cma_test to request 2MB(2048KB) >>> >>> Any read request to /dev/cma_test will let the module to free the 1st >>> valid >>> memory from CMA, for example: >>> >>> 1st time >>> $ cat /dev/cma_test >>> will require cma_test to free the 1MB allocated in the first write request >>> 2nd time >>> $ cat /dev/cma_test >>> will require cma_test to free the 2MB allocated in the second write >>> request >> >> >> Any reason why using /dev not /proc or /sys? > > pls note it is just a test module to verify CMA at runtime. it is not > important either it is /dev, it is /proc or it is /sys. Why not important? You want it to be merged, don't you? > > any way to make things easier, we take that way. > Why /dev interface is easier than /proc and /sys? Confused, actually I think /proc or /sys should be easier...