linux/drivers/media/common
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
..
b2c2 treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
saa7146 media: media/pci: don't set description for ENUM_FMT 2019-07-22 14:40:32 -04:00
siano treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 185 2019-05-30 11:29:20 -07:00
v4l2-tpg treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
videobuf2 media: vb2-dc: skip CPU sync in map/unmap dma_buf 2019-07-23 11:46:27 -04:00
btcx-risc.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cx2341x.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 2019-05-30 11:26:37 -07:00
cypress_firmware.c treewide: Add SPDX license identifier for more missed files 2019-05-21 10:50:45 +02:00
cypress_firmware.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Kconfig treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
Makefile treewide: Add SPDX license identifier - Makefile/Kconfig 2019-05-21 10:50:46 +02:00
tveeprom.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 2019-05-30 11:26:37 -07:00