[PATCH v3] MM: CMA: add a simple kernel module as the helper to test CMA

[21cnbao@gmail.com (Barry Song)]

2012/3/7 Cong Wang <xiyou.wangcong@gmail.com>:
> 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?

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.

any way to make things easier, we take that way.

-barry