[PATCH v6 0/5] dma-buf: Code rework and performance improvements for system heap

[John Stultz]

Hey All,
  So just wanted to send another revision of my patch series
of performance optimizations to the dma-buf system heap, this
time against drm-misc-next.

This series reworks the system heap to use sgtables, and then
consolidates the pagelist method from the heap-helpers into the
CMA heap. After which the heap-helpers logic is removed (as it
is unused). I'd still like to find a better way to avoid some of
the logic duplication in implementing the entire dma_buf_ops
handlers per heap. But unfortunately that code is tied somewhat
to how the buffer's memory is tracked. As more heaps show up I
think we'll have a better idea how to best share code, so for
now I think this is ok.

After this, the series introduces an optimization that
Ørjan Eide implemented for ION that avoids calling sync on
attachments that don't have a mapping.

Finally, an optimization to use larger order pages for the system
heap. This change brings us closer to the current performance
of the ION allocation code (though there still is a gap due
to ION using a mix of deferred-freeing and page pools, I'll be
looking at integrating those eventually).

This version of the series does not include the system-uncached
heap as Daniel wanted further demonstration that it is useful
with devices that use the mesa stack. I'm working on such a
justification but I don't want to hold up these rework patches
in the meantime.

thanks
-john

New in v6:
* Dropped the system-uncached heap submission for now
* Rebased onto drm-misc-next

Cc: Sumit Semwal <sumit.semwal at linaro.org>
Cc: Liam Mark <lmark at codeaurora.org>
Cc: Laura Abbott <labbott at kernel.org>
Cc: Brian Starkey <Brian.Starkey at arm.com>
Cc: Hridya Valsaraju <hridya at google.com>
Cc: Suren Baghdasaryan <surenb at google.com>
Cc: Sandeep Patil <sspatil at google.com>
Cc: Daniel Mentz <danielmentz at google.com>
Cc: Chris Goldsworthy <cgoldswo at codeaurora.org>
Cc: Ørjan Eide <orjan.eide at arm.com>
Cc: Robin Murphy <robin.murphy at arm.com>
Cc: Ezequiel Garcia <ezequiel at collabora.com>
Cc: Simon Ser <contact at emersion.fr>
Cc: James Jones <jajones at nvidia.com>
Cc: linux-media at vger.kernel.org
Cc: dri-devel at lists.freedesktop.org

John Stultz (5):
  dma-buf: system_heap: Rework system heap to use sgtables instead of
    pagelists
  dma-buf: heaps: Move heap-helper logic into the cma_heap
    implementation
  dma-buf: heaps: Remove heap-helpers code
  dma-buf: heaps: Skip sync if not mapped
  dma-buf: system_heap: Allocate higher order pages if available

 drivers/dma-buf/heaps/Makefile       |   1 -
 drivers/dma-buf/heaps/cma_heap.c     | 325 +++++++++++++++++----
 drivers/dma-buf/heaps/heap-helpers.c | 274 ------------------
 drivers/dma-buf/heaps/heap-helpers.h |  53 ----
 drivers/dma-buf/heaps/system_heap.c  | 411 ++++++++++++++++++++++++---
 5 files changed, 640 insertions(+), 424 deletions(-)
 delete mode 100644 drivers/dma-buf/heaps/heap-helpers.c
 delete mode 100644 drivers/dma-buf/heaps/heap-helpers.h

-- 
2.17.1