From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 28E1A39F187; Tue, 1 Sep 2026 04:34:31 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788237272; cv=none; b=NO4eA/B4wg8xGoZAifIq6quqLbf/bvf9hMcu03te0QjtzLTb0pg4oMGjc2NOIN0P59RhcRVNNTLfnw9bavNqtPfpWO7d+UBYXpbWHqDgFEs40E9Coxpkr5OOb9UKILYtvGXC7jC6oKYbBFMb9t1agSiuHMus6tCqFuq+aguAWU8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788237272; c=relaxed/simple; bh=AsHoCbwMwQPn54Uh42zQM6XfaiQXavuQ492jVm131qQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VHl11nsPFAWumELyxPQOfNLZ9jdfTQfbiWRJNt+L2A7Dig3NPbC3hZiguBlhYILOFRxtMdxS9b56V0UKrtTZEv41dbG8y8REuAQFbr1BYFu6kfsgc3Xk94hNKMq34ot4284EcSUaVcamZVFxpCrKKbaJLwHnC0pZ2rvqcOVUiG8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=d4qUsh8V; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="d4qUsh8V" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 88F3E1F00ACA; Tue, 1 Sep 2026 04:34:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788237271; bh=CpXkgOmW3GSwhrOkMdO/S1mj76NXWWV8m3WM4J70bcE=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=d4qUsh8VH6LG0mrJ6UNN3Jmg4osXJJohaxTB0Tj3iJ77xaBCrcot88uzDIWSNkDZi UEeh4znBav5abJT/ZG696xoT7Al9mWLGavrWxSRxE0tFzqDQ3fTGk/u3JZ+Q95ztEP SLBmtPKBwaHdUmeq4fJOW8jQbnfWXbElgjXM/Xwqu8w0/uOpUb/Eay/Bcit2poEAeF F2nC4/Id69cJkDxkrqC4I/zbYbB7lsBC0NvXzca7jfHBC62I5ex3SbseQ979G/hJgs VftSP7PQYTafZz2PyBGVmlL458eRpXYo/vHjdBO1JPqKOUxp5CNsCVK/N/pn77+o53 h1NoDO/LgNPEA== From: SJ Park To: Andrew Morton Cc: SJ Park , "Liam R. Howlett" , David Hildenbrand , Jonathan Corbet , Lorenzo Stoakes , Michal Hocko , Mike Rapoport , Randy Dunlap , Shuah Khan , Suren Baghdasaryan , Vlastimil Babka , damon@lists.linux.dev, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 15/17] Docs/mm/damon/design: document probe preps Date: Mon, 31 Aug 2026 21:34:11 -0700 Message-ID: <20260901043417.2165-16-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260901043417.2165-1-sj@kernel.org> References: <20260901043417.2165-1-sj@kernel.org> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Update DAMON design document for the newly added DAMON probe preps feature. Signed-off-by: SJ Park --- Documentation/mm/damon/design.rst | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/Documentation/mm/damon/design.rst b/Documentation/mm/damon/design.rst index 947d91ae24a39..d036340dae8af 100644 --- a/Documentation/mm/damon/design.rst +++ b/Documentation/mm/damon/design.rst @@ -309,6 +309,13 @@ Users can therefore know how much of a given DAMON region has a specific data attribute by reading the per-region per-probe probe hits counter after each aggregation interval. +Users can optionally register probing preparation actions per probe. If such +actions are registered, DAMON applies the actions to each region's sampling +memory before starting the next sampling interval. Currently only one action, +``set_pgidle`` is supported. The action marks the page for the probing target +memory as access-idle. This can be useful to be used together with +``pgidle_unset`` probe filter. + This is a sampling based mechanism. Hence, it is lightweight but the output may include some measurement errors. The output should be used with good understanding of statistics. -- 2.47.3