Hey All, So this is another revision of my patch series to performance optimizations to the dma-buf system heap.
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.
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.
Next, 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).
Finally, a reworked version of my uncached system heap implementation I was submitting a few weeks back. Since it duplicated a lot of the now reworked system heap code, I realized it would be much simpler to add the functionality to the system_heap implementaiton itself.
While not improving the core allocation performance, the uncached heap allocations do result in *much* improved performance on HiKey960 as it avoids a lot of flushing and invalidating buffers that the cpu doesn't touch often.
Feedback on these would be great!
thanks -john
New in v4: * Make sys_heap static (indirectly) Reported-by: kernel test robot lkp@intel.com * Spelling fixes suggested by BrianS * Make sys_uncached_heap static, as Reported-by: kernel test robot lkp@intel.com * Fix wrong return value, caught by smatch Reported-by: kernel test robot lkp@intel.com Reported-by: Dan Carpenter dan.carpenter@oracle.com * Ensure we call flush/invalidate_kernel_vmap_range() in the uncached cases to try to address feedback about VIVT caches from Christoph * Reorder a few lines as suggested by BrianS * Avoid holding the initial mapping for the lifetime of the buffer as suggested by BrianS * Fix a unlikely race between allocate and updating the dma_mask that BrianS noticed.
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 (7): 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 dma-buf: dma-heap: Keep track of the heap device struct dma-buf: system_heap: Add a system-uncached heap re-using the system heap
drivers/dma-buf/dma-heap.c | 33 +- drivers/dma-buf/heaps/Makefile | 1 - drivers/dma-buf/heaps/cma_heap.c | 327 +++++++++++++++--- drivers/dma-buf/heaps/heap-helpers.c | 270 --------------- drivers/dma-buf/heaps/heap-helpers.h | 53 --- drivers/dma-buf/heaps/system_heap.c | 488 ++++++++++++++++++++++++--- include/linux/dma-heap.h | 9 + 7 files changed, 749 insertions(+), 432 deletions(-) delete mode 100644 drivers/dma-buf/heaps/heap-helpers.c delete mode 100644 drivers/dma-buf/heaps/heap-helpers.h