Re: [PATCH] mm/damon/core: fix damos_commit_filter not changing allow

[SeongJae Park <sj@kernel.org>]

On Sat, 16 Aug 2025 10:18:13 +0900 Sang-Heon Jeon <ekffu200098@gmail.com> wrote:

> Hi SeongJae
> 
> On Sat, Aug 16, 2025 at 2:25 AM SeongJae Park <sj@kernel.org> wrote:
> >
> > On Fri, 15 Aug 2025 18:40:59 +0900 Sang-Heon Jeon <ekffu200098@gmail.com> wrote:
> >
> > > Current damos_commit_filter() not persist allow value of filter. As a
> > > result, changing allow value of filter and commit doesn't change
> > > allow value.
> > >
> > > Add the missing allow value update, so commit filter now persist changing
> > > allow value well.
> >
> > Thank you for finding and fixing this!
> >
> > >
> > > Fixes: 9cb3d0b9dfce ("mm/damon/core: implement DAMON context commit function")
> >
> > At the time of the commit, damos_filter->allow didn't exist.  I think below is
> > more correct.
> >
> > Fixes: fe6d7fdd6249 ("mm/damon/core: add damos_filter->allow field")
> 
> I found a wrong commit, I'll fix them.
> 
> > Also,
> >
> > Cc: stablee@vger.kernel.org # 6.14.x
> 
> I'll also add them.
> 
> > > Signed-off-by: Sang-Heon Jeon <ekffu200098@gmail.com>
> > > ---
> > > While fixing kselftest, I found another bug and succeeded in
> > > reproducing. I think this patch is similar with previeous patch [1].
> > > Also instead of sending patch with test, should we check which is better:
> > > a seperate patch or patchset?
> >
> > Separate patches are better for me.
> >
> > I'm not sure how you will make the test, but I'd usggest making the test as a
> > kunit test.
> > Please refer to mm/damon/tets/core-kunit.h file.
> 
> I made kselftest with drgn, but I think that kunit could be a solution as well.

Thank you :)  I prefer kunit here, since the test should be for the specific
core function that can easily be tested using kunit.  Writing it as a drgn
based selftest seems too much to me.

> Honestly, I haven't used kunit test before, so i need to look into of
> that. Please just wait a little bit.

No worry, take your time and fun :)

FYI, you can run DAMON kunit test as below:

    $ ./tools/testing/kunit/kunit.py run --kunitconfig ./mm/damon/tests

And the document is available at
https://docs.kernel.org/dev-tools/kunit/index.html


Thanks,
SJ

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