[PATCH v2 00/10] CMA: generalize CMA reserved area management code

Aneesh Kumar K.V aneesh.kumar at linux.vnet.ibm.com
Mon Jun 16 00:04:14 PDT 2014


Joonsoo Kim <iamjoonsoo.kim at lge.com> writes:

> On Sat, Jun 14, 2014 at 12:55:39PM +0530, Aneesh Kumar K.V wrote:
>> Joonsoo Kim <iamjoonsoo.kim at lge.com> writes:
>> 
>> > Currently, there are two users on CMA functionality, one is the DMA
>> > subsystem and the other is the kvm on powerpc. They have their own code
>> > to manage CMA reserved area even if they looks really similar.
>> > From my guess, it is caused by some needs on bitmap management. Kvm side
>> > wants to maintain bitmap not for 1 page, but for more size. Eventually it
>> > use bitmap where one bit represents 64 pages.
>> >
>> > When I implement CMA related patches, I should change those two places
>> > to apply my change and it seem to be painful to me. I want to change
>> > this situation and reduce future code management overhead through
>> > this patch.
>> >
>> > This change could also help developer who want to use CMA in their
>> > new feature development, since they can use CMA easily without
>> > copying & pasting this reserved area management code.
>> >
>> > v2:
>> >   Although this patchset looks very different with v1, the end result,
>> >   that is, mm/cma.c is same with v1's one. So I carry Ack to patch 6-7.
>> >
>> > Patch 1-5 prepare some features to cover ppc kvm's requirements.
>> > Patch 6-7 generalize CMA reserved area management code and change users
>> > to use it.
>> > Patch 8-10 clean-up minor things.
>> 
>> 
>> I wanted to test the ppc changes and found that the patch series doesn't apply
>> against v3.15 . Do you have a kernel tree which I can clone to test this
>> series ?
>
> This is based on linux-next -next-20140610.
> And my tree is on following link.
>
> https://github.com/JoonsooKim/linux/tree/cma-general-v2.0-next-20140610
>
> But, I think I'm late, because you have already added a Tested-by tag.

linux-next kexec is broken on ppc64, hence I hand picked few of
dependent patches for dma CMA on top of 3.15 and used that for testing.

-aneesh




More information about the linux-arm-kernel mailing list