Re: [PATCH] lib/tests: kunit for associative array

[Jarkko Sakkinen <jarkko@kernel.org>]

On Wed, Oct 14, 2026 at 06:35:50PM +0200, Eric Biggers wrote:
> On Wed, Oct 14, 2026 at 07:01:38PM +0300, Jarkko Sakkinen wrote:
> > This is a kunit test for lib/assoc_array.c, which maintains a shadow model
> > across assoc_array operations, and checks its integrity after every
> > operation.
> > 
> > I wrote a draft version so that I could properly test 'assoc-array-fixes'
> > tag at Linus' tree, and spent today rewriting a new more polished version
> > with as good description as I could possibly could on how the seeded test
> > keys were cherry-picked. Along the way I also tweaked the numbers to be
> > a bit less messier set than in my original version.
> > 
> > The transcripts that follow were executed with this command-line:
> > 
> >     ./tools/testing/kunit/kunit.py run --raw_output assoc_array
> > 
> > With 'assoc-array-fixes' commits and its subsequent tag iterations all
> > eight tests pass, and without them all of them fail.
> > 
> > Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
> 
> Would this effort (and Linus's effort) be better spent on converting
> keyrings to use an rhashtable?

It did cross my mind when I reviewed and tested those fixes but you
are asking something that I would need at least a few hours to have
any opinion.

We do bugs and QA to the end-of-life-cycle. We neither can predict
exact time how such major overhaul would take, if we even want to
do it. I don't know.

My brain is on this and I'm really bad at multitasking :-)

> 
> keyrings is the only user of assoc_array.  So if it's made to use
> something else, assoc_array (all 1724 lines of it!) can just be deleted.
> 
> I understand assoc_array.c was intended to be for general use.  But
> clearly that hasn't happened in the 13 years it's been in the kernel.
> Keyrings has always been its only user.  All other kernel code needing a
> map data structure uses something else.
> 
> - Eric

Br, Jarkko