On Mon, Nov 15, 2021 at 02:07:15PM +0100, Christoph Hellwig wrote:

filter.rst starts out documenting the classic BPF and then spills into
introducing and documentating eBPF.  Split the eBPF documentation into
three new files under Documentation/bpf/ and link to that.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 Documentation/bpf/index.rst           |   30 +-
 Documentation/bpf/instruction-set.rst |  491 ++++++++++++
 Documentation/bpf/maps.rst            |   43 +
 Documentation/bpf/verifier.rst        |  533 +++++++++++++
 Documentation/networking/filter.rst   | 1059 +------------------------

...

+.. Links:
+.. _eBPF: ../bpf/instrution-set.rst

I think the split would be good in the long term, but please make the links
more obvious somehow in the filter.rst, since a bunch of posts on the web
link back to that file. The folks who will be reading the revamped filter.rst
would need a very obvious way to navigate to new pages.

In terms of followups and cleanup... please share what you have in mind.