From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.mindbit.ro (xs1.mindbit.ro [80.86.107.70]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6BF6A3630BA for ; Mon, 24 Aug 2026 15:02:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=80.86.107.70 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787583764; cv=none; b=sOxOyCZpbVCNPBzewh3sYZbpClX2FS/CnQgwSNmxqIQKecvAUW+JhlPqRcPmWZ/sarRqmke1SWSZCOEQOnD4Gq9p7xLZGZswQOUvNjYeygzmG8im1GtH9iqg6c12zcMw3gfn6OV3VtxMpuULjkqThbbmuyyJ7sdJRhlrId+mNAg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787583764; c=relaxed/simple; bh=8iLEyLjTsHPN2wex0UnaSt8HRxme1dRnuNtD2yuF9Uo=; h=Message-ID:Subject:From:To:Cc:Date:In-Reply-To:References: Content-Type:MIME-Version; b=ELToOMqvdqhnxPe/Buj+B637Hi19A0WkHqqL2sr71UqeEaU/ajh5zVjux7ag6qYSTqSktdTvFNgLtkTrWxkTJ+3dXGhmatqNUTw5JQgQ+h8Agp7D1A+LR0+l2HvVbgwlrs7DNWLdav6rFj7NUHdmOCXhU0DeAZDJ5fOD/Xt+EwA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=rendec.net; spf=pass smtp.mailfrom=rendec.net; dkim=pass (2048-bit key) header.d=rendec.net header.i=@rendec.net header.b=Jb0myuJZ; arc=none smtp.client-ip=80.86.107.70 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=rendec.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rendec.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=rendec.net header.i=@rendec.net header.b="Jb0myuJZ" Received: from bat.kanata.rendec.net (unknown [72.143.213.78]) by mail.mindbit.ro (Postfix) with ESMTPSA id CCCB9CC8D8; Mon, 24 Aug 2026 18:02:31 +0300 (EEST) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.mindbit.ro CCCB9CC8D8 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rendec.net; s=default; t=1787583758; bh=8iLEyLjTsHPN2wex0UnaSt8HRxme1dRnuNtD2yuF9Uo=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=Jb0myuJZbkBJl8Bpkwbsn5hKDblzUe3kzqXUXJCE3ks9e6Zqq4yj7wjRKf99abLju EDD/wKUpqhC8cMUA0l+cDVP9TewUjrAPO9ZThi0noYPGzxvzcFS5ROMypIsmURtTUu iLgmyaTbda74R+ByND1Q4uXsA4O39kw1ZklFs5PKEWEYDd8DvqDOkVYa3ya0YjWI11 ilw1sir+vW/TqNzXyqJfXSb/3tdjp64PCVpaalNZSBxMR9h3hiKGDfwW7/C+BNbdar ZyTsuY8+mHQcvElTYNOJzzN1YOO4VJ7aS6TAvKSpmC3wrI2BtSGkK537FUOdW3WsDd Q7LyBjLXjOIAQ== Message-ID: <0ae1284074ffda8681b08e8fdee50a413a163d4d.camel@rendec.net> Subject: Re: [PATCH] irq: Make refcount_interrupt kunit test selectable From: Radu Rendec To: Boqun Feng Cc: Kuan-Wei Chiu , tglx@kernel.org, peterz@infradead.org, lyude@redhat.com, jserv@ccns.ncku.edu.tw, marscheng@google.com, eleanor15x@gmail.com, linux-kernel@vger.kernel.org Date: Mon, 24 Aug 2026 11:02:26 -0400 In-Reply-To: References: <20260823171721.3059733-1-visitorckw@gmail.com> <014ccedef7256efc027b8759134b9d1712d3afb6.camel@rendec.net> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.58.3 (3.58.3-1.fc43) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 On Sun, 2026-08-23 at 22:23 -0700, Boqun Feng wrote: > On Sun, Aug 23, 2026 at 05:52:24PM -0400, Radu Rendec wrote: > > On Sun, 2026-08-23 at 14:08 -0700, Boqun Feng wrote: > > > On Sun, Aug 23, 2026 at 04:46:23PM -0400, Radu Rendec wrote: > > > > On Sun, 2026-08-23 at 17:17 +0000, Kuan-Wei Chiu wrote: > > > > > Currently, refcount_interrupt_test is built unconditionally when > > > > > CONFIG_KUNIT is enabled, causing it to run unexpectedly during bo= ot. > > > > >=20 > > > > > Fix this by introducing CONFIG_REFCOUNT_INTERRUPT_KUNIT_TEST so t= he > > > > > test can be configured independently, following standard kunit > > > > > practices. > > > > >=20 > > > > > Fixes: 07a88e2bcd5b ("irq: Add KUnit test for refcounted interrup= t enable/disable") > > > > > Signed-off-by: Kuan-Wei Chiu > > > > > --- > > > > > =C2=A0kernel/irq/Kconfig=C2=A0 | 12 ++++++++++++ > > > > > =C2=A0kernel/irq/Makefile |=C2=A0 2 +- > > > > > =C2=A02 files changed, 13 insertions(+), 1 deletion(-) > > > >=20 > > > > Can someone please explain me why this needs to be a separate unit = test > > > > in the first place and can't be integrated into the (previously) > > > > existing unit test gated by IRQ_KUNIT_TEST? > > > >=20 > > >=20 > > > If you look at the irq_test.c, you will find that it primarily tests = the > > > {request,disable,enable}_irq() API (i.e. allocating IRQ vectors and > > > enabling and disabling them), which is not the same scope as > > > local_interrupt_{disable,enable}() (i.e. operating the CPU irq disabl= ing > > > status), so it makes sense to have a separate test case. > >=20 > > Thanks! If we want to keep the unit tests separated/grouped by scope, > > then yes, it makes sense for sure. What I don't like about this is: > > =C2=A0* The naming of the two config options is inconsistent: IRQ_KUNIT= _TEST > > =C2=A0=C2=A0 and REFCOUNT_INTERRUPT_KUNIT_TEST. > > =C2=A0* The naming and description of the older test become misleading.= The > > =C2=A0=C2=A0 way they are formulated, I would expect them to test "ever= ything > > =C2=A0=C2=A0 related to IRQ" but now we have a separate option (and kun= it test) > > =C2=A0=C2=A0 dedicated to the refcount stuff. > >=20 >=20 > These are valid points. However, I think the "inconsistency" comes from > refcount_interrupt_test.c being in kernel/irq/. IRQ management (code in > kernel/irq/) and IRQ disabling/enabling are very different things to me I agree, they are different indeed, which is a good reason to keep the tests separated as you pointed out. > (for example include/linux/irqflags.h is not listed in the "IRQ > SUBSYSTEM" entry). It's not, and neither are a bunch of other IRQ related header files in include/linux/ (get_maintainer.pl returns just the generic linux-kernel mailing list). To me, that looks more like an omission, because it means they have no maintainer. > IMO, refcount_interrupt_test.c should be moved into > lib/tests/. I'm not sure about that. I looked, and and the tests in lib/tests/ are for the stuff that's implemented in lib/*.c. On the other hand, most of the IRQ refcount code is in include/linux/interrupt_rc.h, with some bits in kernel/softirq.c (e.g. the per-cpu state variable). If the IRQ refcount code hadn't consisted of mostly static inline functions, where would that code have been added? Still kernel/softirq.c? I'm thinking the corresponding unit tests belong in the same place, whatever that is. Assuming kernel/softirq.c, I would have suggested to put the unit tests in kernel/tests/, but it doesn't exist :) > > If they must be separated/grouped by scope, I would find it much nicer > > and less confusing if they were called something like: > > IRQ_MANAGEMENT_KUNIT_TEST and > > IRQ_REFCOUNT_KUNIT_TEST, > > and also the corresponding .c files were somewhat consistent with the > > Kconfig option names. The description of the older test would have to > > be updated to make it clear that it's not just "everything IRQ". > >=20 > > In that scenario, new kunit test(s) related to different aspects of the > > IRQ subsystem would get their own Kconfig option and file, and would > > hopefully follow the same naming pattern. > >=20 > > To be clear, I'm not arguing that keeping the tests separate is wrong. > > I'm arguing that if we do that, we should also make some adjustments to > > keep everything clean and tidy. > >=20 >=20 > Understood, and thank you for bringing it up.=20 No problem. And thank you for not taking it the wrong way :) > So how about we keep Kuan-Wei's fix as it is and move the > refcount_interrupt_test.c file into lib/tests/? It's more clean and tidy > to me this way. Thoughts? I'm fine with taking Kuan-Wei's patch as it is. It fixes a real problem, and the test code is already there (in kernel/irq/), it's not like the patch is putting it there. Meanwhile, we can keep discussing to find a better home for the test code and move it in a future patch. I'll send a r-b tag separately. > > > But yes, I agree Kuan-Wei's fix is needed. > >=20 > > Yes, I agree, those unit tests must not be gated by KUNIT alone, so > > something must be done to fix it. > >=20 > > > > Ironically, both the issue that this patch is trying to fix and my > > > > question were raised by sashiko here: > > > > https://lore.kernel.org/all/20260605055315.3E96E1F00893@smtp.kernel= .org/ > > > >=20 > > > > > diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig > > > > > index 05cba4e16dad..6923f37eaab4 100644 > > > > > --- a/kernel/irq/Kconfig > > > > > +++ b/kernel/irq/Kconfig > > > > > @@ -150,6 +150,18 @@ config IRQ_KUNIT_TEST > > > > > =C2=A0 > > > > > =C2=A0 =C2=A0 If unsure, say N. > > > > > =C2=A0 > > > > > +config REFCOUNT_INTERRUPT_KUNIT_TEST > > > > > + tristate "Test refcounted interrupt enable/disable" if !KUNIT_A= LL_TESTS > > > > > + depends on KUNIT > > > > > + default KUNIT_ALL_TESTS > > > > > + help > > > > > + =C2=A0 This builds the kunit tests for the refcounted interrupt > > > > > + =C2=A0 infrastructure. It verifies the correctness of single, n= ested, > > > > > + =C2=A0 and multiple interrupt enable/disable state changes and = ensures > > > > > + =C2=A0 that the underlying reference counting mechanisms work a= s expected. > > > > > + > > > > > + =C2=A0 If unsure, say N. > > > > > + > > > > > =C2=A0endmenu > > > > > =C2=A0 > > > > > =C2=A0config GENERIC_IRQ_MULTI_HANDLER > > > > > diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile > > > > > index 44c4d6fc502a..0e5df962a149 100644 > > > > > --- a/kernel/irq/Makefile > > > > > +++ b/kernel/irq/Makefile > > > > > @@ -16,4 +16,4 @@ obj-$(CONFIG_SMP) +=3D affinity.o > > > > > =C2=A0obj-$(CONFIG_GENERIC_IRQ_DEBUGFS) +=3D debugfs.o > > > > > =C2=A0obj-$(CONFIG_GENERIC_IRQ_MATRIX_ALLOCATOR) +=3D matrix.o > > > > > =C2=A0obj-$(CONFIG_IRQ_KUNIT_TEST) +=3D irq_test.o > > > > > -obj-$(CONFIG_KUNIT) +=3D refcount_interrupt_test.o > > > > > +obj-$(CONFIG_REFCOUNT_INTERRUPT_KUNIT_TEST) +=3D refcount_interr= upt_test.o >=20 --=20 Best regards, Radu