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Andrii Nakryiko
bbb41728e6
Björn Töpel says:
====================
This two-patch series introduces load-acquire/store-release barriers
for the AF_XDP rings.
For most contemporary architectures, this is more effective than a
SPSC ring based on smp_{r,w,}mb() barriers. More importantly,
load-acquire/store-release semantics make the ring code easier to
follow.
This is effectively the change done in commit 6c43c091bd
("documentation: Update circular buffer for
load-acquire/store-release"), but for the AF_XDP rings.
Both libbpf and the kernel-side are updated.
Full details are outlined in the commits!
Thanks to the LKMM-folks (Paul/Alan/Will) for helping me out in this
complicated matter!
Changelog
v1[1]->v2:
* Expanded the commit message for patch 1, and included the LKMM
litmus tests. Hopefully this clear things up. (Daniel)
* Clarified why the smp_mb()/smp_load_acquire() is not needed in (A);
control dependency with load to store. (Toke)
[1] https://lore.kernel.org/bpf/20210301104318.263262-1-bjorn.topel@gmail.com/
Thanks,
Björn
====================
Signed-off-by: Andrii Nakryiko <andrii@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.