Subject: Re: [PATCH -V2 1/4] mm/cma: Move dma contiguous changes into a seperate config

From: "Aneesh Kumar K.V" <[email-masked]>
Date: Mon, 01 Jul 2013 18:31:10 +0530

Michal Nazarewicz <[email-masked]> writes:

> On Fri, Jun 28 2013, Aneesh Kumar K.V wrote:
>> From: "Aneesh Kumar K.V" <[email-masked]>
>>
>> We want to use CMA for allocating hash page table and real mode area for
>> PPC64. Hence move DMA contiguous related changes into a seperate config
>> so that ppc64 can enable CMA without requiring DMA contiguous.
>>
>> Signed-off-by: Aneesh Kumar K.V <[email-masked]>
>
> Acked-by: Michal Nazarewicz <[email-masked]>
>
>> diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig
>> index 07abd9d..74b7c98 100644
>> --- a/drivers/base/Kconfig
>> +++ b/drivers/base/Kconfig
>> @@ -202,11 +202,10 @@ config DMA_SHARED_BUFFER
>>  	  APIs extension; the file's descriptor can then be passed on to other
>>  	  driver.
>>  
>> -config CMA
>> -	bool "Contiguous Memory Allocator"
>> -	depends on HAVE_DMA_CONTIGUOUS && HAVE_MEMBLOCK
>> -	select MIGRATION
>> -	select MEMORY_ISOLATION
>> +config DMA_CMA
>> +	bool "DMA Contiguous Memory Allocator"
>> +	depends on HAVE_DMA_CONTIGUOUS
>> +	select CMA
>
> Just to be on the safe side, I'd add
>
> 	depends on HAVE_MEMBLOCK
>
> or change this so that it does not select CMA but depends on CMA.

updated this to 

+config DMA_CMA
+	bool "DMA Contiguous Memory Allocator"
+	depends on HAVE_DMA_CONTIGUOUS && CMA

>
>>  	help
>>  	  This enables the Contiguous Memory Allocator which allows drivers
>>  	  to allocate big physically-contiguous blocks of memory for use with
>> @@ -215,17 +214,7 @@ config CMA
>>  	  For more information see <include/linux/dma-contiguous.h>.
>>  	  If unsure, say "n".
>>  
>> -if CMA
>> -
>> -config CMA_DEBUG
>> -	bool "CMA debug messages (DEVELOPMENT)"
>> -	depends on DEBUG_KERNEL
>> -	help
>> -	  Turns on debug messages in CMA.  This produces KERN_DEBUG
>> -	  messages for every CMA call as well as various messages while
>> -	  processing calls such as dma_alloc_from_contiguous().
>> -	  This option does not affect warning and error messages.
>> -

Thanks
-aneesh