diff options
| author | Jason Gunthorpe | 2020-10-09 12:56:02 -0300 |
|---|---|---|
| committer | Jason Gunthorpe | 2020-10-16 12:40:58 -0300 |
| commit | 16e7483e6f02973972f832b18042fd6c45fe26c0 (patch) | |
| tree | 205122d1996a983619ccd55c572c34f037a76718 /Documentation/userspace-api/media/v4l/buffer.rst | |
| parent | bf6a47644ea0928b2a6589ba9fb1221116d8bfaf (diff) | |
| parent | 0c16d9635e3a51377e5815b9f8e14f497a4dbb42 (diff) | |
Merge branch 'dynamic_sg' into rdma.git for-next
From Maor Gottlieb says:
====================
This series extends __sg_alloc_table_from_pages to allow chaining of new
pages to an already initialized SG table.
This allows for drivers to utilize the optimization of merging contiguous
pages without a need to pre allocate all the pages and hold them in a very
large temporary buffer prior to the call to SG table initialization.
The last patch changes the Infiniband core to use the new API. It removes
duplicate functionality from the code and benefits from the optimization
of allocating dynamic SG table from pages.
In huge pages system of 2MB page size, without this change, the SG table
would contain x512 SG entries.
====================
* branch 'dynamic_sg':
RDMA/umem: Move to allocate SG table from pages
lib/scatterlist: Add support in dynamic allocation of SG table from pages
tools/testing/scatterlist: Show errors in human readable form
tools/testing/scatterlist: Rejuvenate bit-rotten test
Diffstat (limited to 'Documentation/userspace-api/media/v4l/buffer.rst')
| -rw-r--r-- | Documentation/userspace-api/media/v4l/buffer.rst | 17 |
1 files changed, 0 insertions, 17 deletions
diff --git a/Documentation/userspace-api/media/v4l/buffer.rst b/Documentation/userspace-api/media/v4l/buffer.rst index 57e752aaf414..2044ed13cd9d 100644 --- a/Documentation/userspace-api/media/v4l/buffer.rst +++ b/Documentation/userspace-api/media/v4l/buffer.rst @@ -701,23 +701,6 @@ Memory Consistency Flags :stub-columns: 0 :widths: 3 1 4 - * .. _`V4L2-FLAG-MEMORY-NON-CONSISTENT`: - - - ``V4L2_FLAG_MEMORY_NON_CONSISTENT`` - - 0x00000001 - - A buffer is allocated either in consistent (it will be automatically - coherent between the CPU and the bus) or non-consistent memory. The - latter can provide performance gains, for instance the CPU cache - sync/flush operations can be avoided if the buffer is accessed by the - corresponding device only and the CPU does not read/write to/from that - buffer. However, this requires extra care from the driver -- it must - guarantee memory consistency by issuing a cache flush/sync when - consistency is needed. If this flag is set V4L2 will attempt to - allocate the buffer in non-consistent memory. The flag takes effect - only if the buffer is used for :ref:`memory mapping <mmap>` I/O and the - queue reports the :ref:`V4L2_BUF_CAP_SUPPORTS_MMAP_CACHE_HINTS - <V4L2-BUF-CAP-SUPPORTS-MMAP-CACHE-HINTS>` capability. - .. c:type:: v4l2_memory enum v4l2_memory |