From nobody Sat Apr 11 10:46:30 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 719543D34B9; Fri, 6 Mar 2026 15:29:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772810963; cv=none; b=dV6XzVco90hxR+NSHJCI7aag/Rz9ynzjuSI/lxsV2oBZu/kH0DpL5ExNTUkn2GY3UElQKyvghfNl34j3hLYXoqRNha76fspSAr9qGOaL/XhvCVv9+82WUmM7mvPRaVcsyV5P1A0rNYWaUPQnVm1zatoK3QaEPIGY1GUNvTBbh3k= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772810963; c=relaxed/simple; bh=zFDrPDtcwfulSyFJOaJh2lietZw1gfebL6litU0OglA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=D9cMaznrkk1yoVpGfYn9FRfuHYhnlEk+ZYPEnzkh+ICxqw8Df25k0wpvJn9bPgGAakpS2BChAqHJ1aCmqeE5gZt7F1Ond4ci1D/3dBjOOUatHGsib3armMsaxK91YtD/wHWCAlB9DaeTOApw+9QABUm9op6uqV11qGbi8qRgjks= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ZeVHgsPR; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="ZeVHgsPR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C4B7BC2BCB8; Fri, 6 Mar 2026 15:29:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1772810962; bh=zFDrPDtcwfulSyFJOaJh2lietZw1gfebL6litU0OglA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZeVHgsPRrSNZYiyck/thY8pd39Z2lv1DqP49urnH198fOG/D+Xwtzp0LgzidbnQFF +duTf5sg/49BkaZw9XXTxLBdkbqs56OBwRUohllckGSdBmMsFmjovUjmplvA7zzuS+ Q6QBvdOgPyNl6a+bjkghYiN5Mf1xTjGJq6hv7m8e4K3+AKZ5w9DwufSyO+MESEkHGR yXDDjXuhCETJnCakfcEUIGdZqfHhogaAhSpKeDfRCWWRa+VJNkEgFDvTYK9hAJ5S0G nxxCzoy++/eO6+Vz+iU7r/jnCeChX4s7vpQNbHReZvYE82d34Nokkknce6zA3IBXEV MG3YT5q/So35g== From: SeongJae Park To: Andrew Morton Cc: SeongJae Park , damon@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 04/10] mm/damon/core: add damon_nr_regions() debug_sanity check Date: Fri, 6 Mar 2026 07:29:07 -0800 Message-ID: <20260306152914.86303-5-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260306152914.86303-1-sj@kernel.org> References: <20260306152914.86303-1-sj@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" damon_target->nr_regions is introduced to get the number quickly without having to iterate regions always. Add a sanity check for that under CONFIG_DAMON_DEBUG_SANITY. Signed-off-by: SeongJae Park --- mm/damon/core.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/mm/damon/core.c b/mm/damon/core.c index 92eac5eb96026..2b5aed89d449d 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -545,8 +545,27 @@ void damon_destroy_target(struct damon_target *t, stru= ct damon_ctx *ctx) damon_free_target(t); } =20 +#ifdef CONFIG_DAMON_DEBUG_SANITY +static void damon_verify_nr_regions(struct damon_target *t) +{ + struct damon_region *r; + unsigned int count =3D 0; + + damon_for_each_region(r, t) + count++; + WARN_ONCE(count !=3D t->nr_regions, "t->nr_regions (%u) !=3D count (%u)\n= ", + t->nr_regions, count); +} +#else +static void damon_verify_nr_regions(struct damon_target *t) +{ +} +#endif + unsigned int damon_nr_regions(struct damon_target *t) { + damon_verify_nr_regions(t); + return t->nr_regions; } =20 --=20 2.47.3