linux/drivers/media/common/videobuf2
Lucas Stach 596a5a58e8 media: vb2-dc: skip CPU sync in map/unmap dma_buf
This is rougly equivalent to ca0e68e21a (drm/prime: skip CPU sync
in map/unmap dma_buf). The contig memory allocated is already device
coherent memory, so there is no point in doing a CPU sync when
mapping it to another device. Also most importers currently cache
the mapping so the CPU sync would only happen on the first import,
so we are better off with not pretending to do a cache synchronization
at all.

This gets rid of a lot of CPU overhead in uses where those dma-bufs
are regularily imported and detached again, like Weston is currently
doing in the DRM compositor.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
[hverkuil-cisco@xs4all.nl: fix checkpatch warnings]
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
2019-07-23 11:46:27 -04:00
..
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile media: vb2: Makefile: place vb2-trace together with vb2-core 2018-02-26 11:39:04 -05:00
vb2-trace.c media: videobuf2: fix build issues with vb2-trace 2018-02-23 05:13:53 -05:00
videobuf2-core.c media: videobuf2-core.h: Document the alloc memop size argument as page aligned 2019-05-23 10:18:19 -04:00
videobuf2-dma-contig.c media: vb2-dc: skip CPU sync in map/unmap dma_buf 2019-07-23 11:46:27 -04:00
videobuf2-dma-sg.c media: videobuf2-vmalloc: get_userptr: buffers are always writable 2019-05-29 08:05:58 -04:00
videobuf2-dvb.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152 2019-05-30 11:26:32 -07:00
videobuf2-memops.c media: videobuf2-vmalloc: get_userptr: buffers are always writable 2019-05-29 08:05:58 -04:00
videobuf2-v4l2.c media: vb2: reorder checks in vb2_poll() 2019-07-23 08:44:45 -04:00
videobuf2-vmalloc.c media: videobuf2-vmalloc: get_userptr: buffers are always writable 2019-05-29 08:05:58 -04:00