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 15AF2380FF2; Sat, 25 Jul 2026 21:02:40 +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=1785013361; cv=none; b=oGIHSnslrC6mkNNRMgFb1cfGlPWwon7Vt2ZplWmhviAM9YIJjUE1CKjf9nb5YBlr8U6OQfUAhKHRbyGe4jQDsMyeFkZOsEx882jepr5HhBf3oRPhhQgCK9ZRNNt0EmqyTnV5WLYAJtmmaf34whG0MbCPuFoC8MvGb5u52XAypoI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785013361; c=relaxed/simple; bh=llo5+gV9pnB1/RZRzV4H9W0eVGL+ZdsEibs8sEu0Apw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Y7lnYXtS9OlKjaG+qQcBvW/ghuRK1Iu6m+K0QmXwqhJ/R260821KkS6EwNQ9clKwhU5Lb1fSvp5+InJwt83N0maYHuGy4pI5CV1GCO24Ywkmbqfk2s81jMI3zIh7SCwgiQ7BDgSk7Q5Ag0dSThWLtjn2/61TVo8pD5IkBhByLUo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=nrw9fpOj; 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="nrw9fpOj" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7B2DD1F00A3F; Sat, 25 Jul 2026 21:02:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785013360; bh=DL5R4ny6wLlfbUwSF8IPEKmxBCfPJcB+Bwsr8pb15YA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=nrw9fpOjsyc5AXWhE81QJBrNDwn5daxC2nF65w3wDf8NRQdPlkuA9YG02kY3Btn6j hoAMufMpKL5uR6C9fraSoSoG3Mox9OcYEdtnEFQB74JqH2PHtBR7d2Tjf50l8p45d8 UspB28jK44t/VoZVWScHe/jenTgRdI/2rdCyL7o6zT0MlW6ft3124sfKfHkCJtapE1 9YNLwWMhgKbbxBChIJyXLYNi/usVcnteqo0xNGoJmHolF+ppydh3P2RifoAf5NlNVl KLB0cPx/ycRiRNULQ0C0Wh257Rp1mAie+9AEHzEG4fDG4POuDTyr9uVai09VdGD8nN 1pM2DG2Ap4LZw== From: SJ Park To: Cc: SJ Park , "Liam R. Howlett" , Andrew Morton , David Hildenbrand , Jonathan Corbet , Lorenzo Stoakes , Michal Hocko , Mike Rapoport , 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: [RFC PATCH 15/17] Docs/mm/damon/design: document probe preps Date: Sat, 25 Jul 2026 14:02:19 -0700 Message-ID: <20260725210225.129944-16-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260725210225.129944-1-sj@kernel.org> References: <20260725210225.129944-1-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 DAMN 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 12a2c3f81a262..5ce777c6b3f30 100644 --- a/Documentation/mm/damon/design.rst +++ b/Documentation/mm/damon/design.rst @@ -311,6 +311,13 @@ 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