629a002568
Willem de Bruijn says:
====================
BPF allows for dynamic tunneling, choosing the tunnel destination and
features on-demand. Extend bpf_skb_adjust_room to allow for efficient
tunneling at the TC hooks.
Most features are required for large packets with GSO, as these will
be modified after this patch.
Patch 1
is a performance optimization, avoiding an unnecessary unclone
for the TCP hot path.
Patches 2..6
introduce a regression test. These can be squashed, but the code is
arguably more readable when gradually expanding the feature set.
Patch 7
is a performance optimization, avoid copying network headers
that are going to be overwritten. This also simplifies the bpf
program.
Patch 8
reenables bpf_skb_adjust_room for UDP packets.
Patch 9
configures skb tunneling metadata analogous to tunnel devices.
Patches 10..13
expand the regression test to make use of the new features and
enable the GSO testcases.
Changes
v1->v2
- move BPF_F_ADJ_ROOM_MASK out of uapi as it can be expanded
- document new flags
- in tests replace netcat -q flag with coreutils timeout:
the -q flag is not supported in all netcat versions
v2->v3
- move BPF_F_ADJ_ROOM_ENCAP_L3_MASK out of uapi as it has no
use in userspace
====================
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
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 Restructured Text 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.