Merge branch 'selftests-mark-auto-deferring-functions-clearly'

Petr Machata says:

====================
selftests: Mark auto-deferring functions clearly

selftests/net/lib.sh contains a suite of iproute2 wrappers that
automatically schedule the corresponding cleanup through defer. The fact
they do so is however not immediately obvious, one needs to know which
functions are handling the deferral behind the scenes, and which expect the
caller to handle cleanups themselves.

A convention for these auto-deferring functions would help both writing and
patch review. This patchset does so by marking these functions with an adf_
prefix. We already have a few such functions: forwarding/lib.sh has
adf_mcd_start() and a few selftests add private helpers that conform to
this convention.

Patches #1 to #8 gradually convert individual functions, one per patch.

Patch #9 renames an auto-deferring private helpers named dfr_* to adf_*.
The plan is not to retro-rename all private helpers, but I happened to know
about this one.

Patches #10 to #12 introduce several autodefer helpers for commonly used
forwarding/lib.sh functions, and opportunistically convert straightforward
instances of 'action; defer counteraction' to the new helpers.

Patch #13 adds some README verbiage to pitch defer and the adf_*
convention.
====================

Link: https://patch.msgid.link/cover.1758821127.git.petrm@nvidia.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>