diff options
| author | John Garry <[email protected]> | 2022-07-14 19:15:24 +0800 |
|---|---|---|
| committer | Christoph Hellwig <[email protected]> | 2022-07-19 06:05:41 +0200 |
| commit | a229cc14f3395311b899e5e582b71efa8dd01df0 (patch) | |
| tree | c582777858d9da5c8d70cad910a04859b213fd8f /tools/perf/scripts/python/Perf-Trace-Util/lib/Perf/Trace/EventClass.py | |
| parent | 942a8186eb4451700dadd1d60a2e43ce67605991 (diff) | |
dma-mapping: add dma_opt_mapping_size()
Streaming DMA mapping involving an IOMMU may be much slower for larger
total mapping size. This is because every IOMMU DMA mapping requires an
IOVA to be allocated and freed. IOVA sizes above a certain limit are not
cached, which can have a big impact on DMA mapping performance.
Provide an API for device drivers to know this "optimal" limit, such that
they may try to produce mapping which don't exceed it.
Signed-off-by: John Garry <[email protected]>
Reviewed-by: Damien Le Moal <[email protected]>
Acked-by: Martin K. Petersen <[email protected]>
Signed-off-by: Christoph Hellwig <[email protected]>
Diffstat (limited to 'tools/perf/scripts/python/Perf-Trace-Util/lib/Perf/Trace/EventClass.py')
0 files changed, 0 insertions, 0 deletions