From mboxrd@z Thu Jan 1 00:00:00 1970 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 2FF24322B88; Sat, 21 Feb 2026 19:36:37 +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=1771702597; cv=none; b=QMe2BR1BUJjN9HEHv0RKEAwEwlGyY1SXITCogvq+OmEfR8KaI/1jokk6g7PVq1QmyQ9yEA64UW4F59EEiaJE3g7mSbvv103YESR2lcW/B+BEg/b16fB9s/jnnyDghOlJc6hteB1ZXyM0sA5/wuu02IcaB108zJSfes8aGKVkfzw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1771702597; c=relaxed/simple; bh=h+yGkK1mUlydQHBhuSmFBiMNXZJ33nd1yZsz+jGXjHM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=CfIHSsiCcK4o39qbikB1p83LcC6/Cgywj+ungocx/KidaCn2rphDXZYUMXdxERnKES0v/hnN8vJ/QHqMDHrcM99xnUmL3fRRzgB7Yf0KgsQJWE6ojo9MD9Aa5CuJVxR+WtbE1SWA4G6dkRBJKSJXMZAFZk0habeEhdvUGXWFjxY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=jYxEcmN7; 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="jYxEcmN7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 00F74C19422; Sat, 21 Feb 2026 19:36:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1771702597; bh=h+yGkK1mUlydQHBhuSmFBiMNXZJ33nd1yZsz+jGXjHM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jYxEcmN7X9Ujj0uCpoyQ+P9KlPERhlBrT8vThzywUA+fvZazJSadEOpAf+Mx1YQqk tLTyJvlbFeH6MMW3i6Y+hS2b7mR4ctodUZgKEz+VrHJREQbtwwfFoQ5lemocCmkabK i/B7G38wQxpfe0fN/bBpxj8azjo6TSTWMlJ8LeOr6Y16LeyDpsNIrMRhKy1lawea+m CbuLuK8r2KU1aKXx0uXERmHwbP1vyiDSe9UytRMgVTvumT8y6kr0gQJhzEx6tt9VAX ELTT48NWJSiY2BqbxQQiNb/xXmfAIwiqn2GXS2fIUYxOAI9miNARy/yu3Owi8LHxOw 7doRlHA82ZnMg== From: SeongJae Park To: Cc: SeongJae Park , Andrew Morton , damon@lists.linux.dev, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [RFC PATCH 08/10] mm/damon/core: add damon_reset_aggregated() debug_sanity check Date: Sat, 21 Feb 2026 11:36:25 -0800 Message-ID: <20260221193629.19332-9-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260221193629.19332-1-sj@kernel.org> References: <20260221193629.19332-1-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: 8bit At time of damon_reset_aggregated(), aggregation of the interval should be completed, and hence nr_accesses and nr_accesses_bp should match. I found a few bugs caused it to be broken in the past, from online parameters update and complicated nr_accesses handling changes. Add a sanity check for that under CONFIG_DAMON_DEBUG_SANITY. Signed-off-by: SeongJae Park --- mm/damon/core.c | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/mm/damon/core.c b/mm/damon/core.c index 16f7994903d6d..4efe732e76c69 100644 --- a/mm/damon/core.c +++ b/mm/damon/core.c @@ -1681,6 +1681,28 @@ static void damon_warn_fix_nr_accesses_corruption(struct damon_region *r) r->nr_accesses_bp = r->nr_accesses * 10000; } +#ifdef CONFIG_DAMON_DEBUG_SANITY +static void damon_verify_reset_aggregated(struct damon_region *r, + struct damon_ctx *c) +{ + if (r->nr_accesses_bp == r->last_nr_accesses * 10000) + return; + pr_err("reset time invalid region found!\n"); + pr_err("nr_accesses_bp %u last_nr_acceses %u\n", + r->nr_accesses_bp, r->last_nr_accesses); + pr_err("passed_sis %lu next_aggregation_sis %lu\n", + c->passed_sample_intervals, + c->next_aggregation_sis); + WARN_ONCE(); +} +#else +static void damon_verify_reset_aggregated(struct damon_region *r, + struct damon_ctx *c) +{ +} +#endif + + /* * Reset the aggregated monitoring results ('nr_accesses' of each region). */ @@ -1697,6 +1719,7 @@ static void kdamond_reset_aggregated(struct damon_ctx *c) damon_warn_fix_nr_accesses_corruption(r); r->last_nr_accesses = r->nr_accesses; r->nr_accesses = 0; + damon_verify_reset_aggregated(r, c); } ti++; } -- 2.47.3