Re: [PATCH v9 0/5] DMA-BUF Heaps (destaging ION)

[Brian Starkey]

Hi John,

On Wed, Oct 02, 2019 at 06:22:50PM +0000, John Stultz wrote:
> Here is yet another pass at the dma-buf heaps patchset Andrew
> and I have been working on which tries to destage a fair chunk
> of ION functionality.
> 
> The patchset implements per-heap devices which can be opened
> directly and then an ioctl is used to allocate a dmabuf from the
> heap.
> 
> The interface is similar, but much simpler then IONs, only
> providing an ALLOC ioctl.
> 
> Also, I've provided relatively simple system and cma heaps.
> 
> I've booted and tested these patches with AOSP on the HiKey960
> using the kernel tree here:
>   https://git.linaro.org/people/john.stultz/android-dev.git/log/?h=dev/dma-buf-heap
> 
> And the userspace changes here:
>   https://android-review.googlesource.com/c/device/linaro/hikey/+/909436
> 
> Compared to ION, this patchset is missing the system-contig,
> carveout and chunk heaps, as I don't have a device that uses
> those, so I'm unable to do much useful validation there.
> Additionally we have no upstream users of chunk or carveout,
> and the system-contig has been deprecated in the common/andoid-*
> kernels, so this should be ok.
> 
> I've also removed the stats accounting, since any such accounting
> should be implemented by dma-buf core or the heaps themselves.
> 
> New in v9:
> * Removing needless check in cma heap (noted by Brian Starkey)
> * Rename dma_heap_get_data->dma_heap_get_drvdata (suggested by
>   Hilf Danton)
> * Check signals after clearing memory pages to avoid doing
>   needless work if the task is killed (suggested by Hilf)
> * Better test error reporting (suggested d by Brian)
> * Other minor cleanups (suggested by Brian)
> 
> Thoughts and feedback would be greatly appreciated!

Looks good to me! Please feel free to add my r-b to the remaining
patches.

Thanks again for moving this forwards.

-Brian

> 
> thanks
> -john
> 
> Cc: Laura Abbott <labbott@xxxxxxxxxx>
> Cc: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxx>
> Cc: Sumit Semwal <sumit.semwal@xxxxxxxxxx>
> Cc: Liam Mark <lmark@xxxxxxxxxxxxxx>
> Cc: Pratik Patel <pratikp@xxxxxxxxxxxxxx>
> Cc: Brian Starkey <Brian.Starkey@xxxxxxx>
> Cc: Vincent Donnefort <Vincent.Donnefort@xxxxxxx>
> Cc: Sudipto Paul <Sudipto.Paul@xxxxxxx>
> Cc: Andrew F. Davis <afd@xxxxxx>
> Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
> Cc: Chenbo Feng <fengc@xxxxxxxxxx>
> Cc: Alistair Strachan <astrachan@xxxxxxxxxx>
> Cc: Hridya Valsaraju <hridya@xxxxxxxxxx>
> Cc: Hillf Danton <hdanton@xxxxxxxx>
> Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
> 
> Andrew F. Davis (1):
>   dma-buf: Add dma-buf heaps framework
> 
> John Stultz (4):
>   dma-buf: heaps: Add heap helpers
>   dma-buf: heaps: Add system heap to dmabuf heaps
>   dma-buf: heaps: Add CMA heap to dmabuf heaps
>   kselftests: Add dma-heap test
> 
>  MAINTAINERS                                   |  18 ++
>  drivers/dma-buf/Kconfig                       |  11 +
>  drivers/dma-buf/Makefile                      |   2 +
>  drivers/dma-buf/dma-heap.c                    | 250 ++++++++++++++++
>  drivers/dma-buf/heaps/Kconfig                 |  14 +
>  drivers/dma-buf/heaps/Makefile                |   4 +
>  drivers/dma-buf/heaps/cma_heap.c              | 169 +++++++++++
>  drivers/dma-buf/heaps/heap-helpers.c          | 266 ++++++++++++++++++
>  drivers/dma-buf/heaps/heap-helpers.h          |  55 ++++
>  drivers/dma-buf/heaps/system_heap.c           | 122 ++++++++
>  include/linux/dma-heap.h                      |  59 ++++
>  include/uapi/linux/dma-heap.h                 |  55 ++++
>  tools/testing/selftests/dmabuf-heaps/Makefile |   9 +
>  .../selftests/dmabuf-heaps/dmabuf-heap.c      | 238 ++++++++++++++++
>  14 files changed, 1272 insertions(+)
>  create mode 100644 drivers/dma-buf/dma-heap.c
>  create mode 100644 drivers/dma-buf/heaps/Kconfig
>  create mode 100644 drivers/dma-buf/heaps/Makefile
>  create mode 100644 drivers/dma-buf/heaps/cma_heap.c
>  create mode 100644 drivers/dma-buf/heaps/heap-helpers.c
>  create mode 100644 drivers/dma-buf/heaps/heap-helpers.h
>  create mode 100644 drivers/dma-buf/heaps/system_heap.c
>  create mode 100644 include/linux/dma-heap.h
>  create mode 100644 include/uapi/linux/dma-heap.h
>  create mode 100644 tools/testing/selftests/dmabuf-heaps/Makefile
>  create mode 100644 tools/testing/selftests/dmabuf-heaps/dmabuf-heap.c
> 
> -- 
> 2.17.1
>