mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/
synced 2026-10-31 05:15:34 +00:00
No description
- C 96.8%
- Assembly 0.9%
- Rust 0.7%
- Shell 0.6%
- Python 0.5%
- Other 0.3%
346fb86ddd
In order to support installing an XDP program on DQ, RX buffers need to be reposted using 4K buffers, which is larger than the default packet buffer size of 2K. This is needed to accommodate the extra head and tail that accompanies the data portion of an XDP buffer. Continuing to use 2K buffers would mean that the packet buffer size for the NIC would have to be restricted to 2048 - 320 - 256 = 1472B. However, this is problematic for two reasons: first, 1472 is not a packet buffer size accepted by GVE; second, at least 1474B of buffer space is needed to accommodate an MTU of 1460, which is the default on GCP. As such, we allocate 4K buffers, and post a 2K section of those 4K buffers (offset relative to the XDP headroom) to the NIC for DMA to avoid a potential extra copy. Because the GQ-QPL datapath requires copies regardless, this change was not needed to support XDP in that case. To capture this subtlety, a new field, packet_buffer_truesize, has been added to the rx ring struct to represent size of the allocated buffer, while packet_buffer_size has been left to represent the portion of the buffer posted to the NIC. Reviewed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Praveen Kaligineedi <pkaligineedi@google.com> Signed-off-by: Joshua Washington <joshwash@google.com> Signed-off-by: Harshitha Ramamurthy <hramamurthy@google.com> Link: https://patch.msgid.link/20250321002910.1343422-6-hramamurthy@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
History
|
|
|---|---|---|
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .clippy.toml | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.