[PATCH v7 0/5] dma-buf: Code rework and performance improvements for system heap

John Stultz
2020-11-21T23:50:28Z

Hey All,
So Sumit noted a flub I made in adapting the last series to
the new dma-buf-map code that is in drm-misc-next. Thus I wanted
to send this (hopefully) last revision of my patch series of
performance optimizations to the dma-buf system heap, once again
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 v7:
* Fixed the incorrect adaptation to the dma-buf-map usage

Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Liam Mark <lmark@codeaurora.org>
Cc: Laura Abbott <labbott@kernel.org>
Cc: Brian Starkey <Brian.Starkey@arm.com>
Cc: Hridya Valsaraju <hridya@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Sandeep Patil <sspatil@google.com>
Cc: Daniel Mentz <danielmentz@google.com>
Cc: Chris Goldsworthy <cgoldswo@codeaurora.org>
Cc: Ørjan Eide <orjan.eide@arm.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Ezequiel Garcia <ezequiel@collabora.com>
Cc: Simon Ser <contact@emersion.fr>
Cc: James Jones <jajones@nvidia.com>
Cc: linux-media@vger.kernel.org
Cc: dri-devel@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 | 329 +++++++++++++++++----
drivers/dma-buf/heaps/heap-helpers.c | 274 ------------------
drivers/dma-buf/heaps/heap-helpers.h | 53 ----
drivers/dma-buf/heaps/system_heap.c | 414 ++++++++++++++++++++++++---
5 files changed, 647 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