Re: [PATCH v2 bpf-next 3/5] bpf: udp: Avoid socket skips and repeats during iteration

[Kuniyuki Iwashima <kuniyu@amazon.com>]

From: Jordan Rife <jordan@jrife.io>
Date: Fri, 11 Apr 2025 10:35:43 -0700
> Replace the offset-based approach for tracking progress through a bucket
> in the UDP table with one based on socket cookies. Remember the cookies
> of unprocessed sockets from the last batch and use this list to
> pick up where we left off or, in the case that the next socket
> disappears between reads, find the first socket after that point that
> still exists in the bucket and resume from there.
> 
> In order to make the control flow a bit easier to follow inside
> bpf_iter_udp_batch, introduce the udp_portaddr_for_each_entry_from macro
> and use this to split bucket processing into two stages: finding the
> starting point and adding items to the next batch. Originally, I
> implemented this patch inside a single udp_portaddr_for_each_entry loop,
> as it was before, but I found the resulting logic a bit messy. Overall,
> this version seems more readable.
> 
> Signed-off-by: Jordan Rife <jordan@jrife.io>

Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>

Thanks!