From mboxrd@z Thu Jan  1 00:00:00 1970
From: xiyou.wangcong@gmail.com (Cong Wang)
Date: Wed, 07 Mar 2012 12:14:36 +0800
Subject: [PATCH v3] MM: CMA: add a simple kernel module as the helper
 to test CMA
In-Reply-To: <1331090098-25097-1-git-send-email-Barry.Song@csr.com>
References: <1331090098-25097-1-git-send-email-Barry.Song@csr.com>
Message-ID: <4F56E0AC.8070501@gmail.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On 03/07/2012 11:14 AM, Barry Song wrote:
> From: Barry Song<Baohua.Song@csr.com>
>
> 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?

From mboxrd@z Thu Jan  1 00:00:00 1970
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Message-ID: <4F56E0AC.8070501@gmail.com>
Date: Wed, 07 Mar 2012 12:14:36 +0800
From: Cong Wang <xiyou.wangcong@gmail.com>
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To: Barry Song <Barry.Song@csr.com>
CC: m.szyprowski@samsung.com, mina86@mina86.com,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        workgroup.linux@csr.com, Barry Song <Baohua.Song@csr.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>
In-Reply-To: <1331090098-25097-1-git-send-email-Barry.Song@csr.com>
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On 03/07/2012 11:14 AM, Barry Song wrote:
> From: Barry Song<Baohua.Song@csr.com>
>
> 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?