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| author |   Dmitry Osipenko <digetx@gmail.com> | 2019-06-23 13:07:30 -0400 |
|---|---|---|
| committer |   Mauro Carvalho Chehab <mchehab+samsung@kernel.org> | 2019-06-24 15:06:17 -0400 |
| commit | 92cd14408be36310743db9b874a13cf6eb3120c1 (patch) | |
| tree | e4dd87981485403504749b46b722b5170473bd24 /tools/perf/scripts/python/exported-sql-viewer.py | |
| parent | media: staging: media: tegra-vde: Add IOMMU support (diff) | |
| download | wireguard-linux-92cd14408be36310743db9b874a13cf6eb3120c1.tar.xz wireguard-linux-92cd14408be36310743db9b874a13cf6eb3120c1.zip | |
media: staging: media: tegra-vde: Defer dmabuf's unmapping
Frequent IOMMU remappings take about 50% of CPU usage because there is
quite a lot to remap. Defer dmabuf's unmapping by 5 seconds in order to
mitigate the mapping overhead which goes away completely and driver works
as fast as in a case of a disabled IOMMU. The case of a disabled IOMMU
should also benefit a tad from the caching since CPU cache maintenance
that happens on dmabuf's attaching takes some resources.
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Diffstat (limited to 'tools/perf/scripts/python/exported-sql-viewer.py')
0 files changed, 0 insertions, 0 deletions