Re: [PATCH bpf-next v2 0/2] load-acquire/store-release barriers for AF_XDP rings

Björn Töpel [off-list ref] writes:

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 6c43c091bdc5
("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!

@Andrii I kept the barriers in libbpf_util.h to separate userfacing
        APIs (xsk.h) from internals.

@Toke I kept "barriers" but reworded. Acquire/release are also
      barriers.

Right, that text is better - thanks!

Acked-by: Toke Høiland-Jørgensen <redacted>