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 D04E83D954C; Sun, 26 Jul 2026 17:39:49 +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=1785087591; cv=none; b=YDFmz4S0FZxL/je+BqmzCalPafBCwVpQmBKPWs+mUt6n+nK7m3pt34jM5R5mklH7NeWYKqOb6lt5SGHlxczUxuDzVE2L04ZAkRyvcxrLG2yYehFwe5HBCi9K4j4Je58IBczAQoir6ofdebOefB0Xw70OqBDnbbjAaBVDhgZINR8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785087591; c=relaxed/simple; bh=xcWvcxTShuREolgVeaNKxOb9JPpBPwIcsH+2uXlYsDc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WDoDk3JgsK1Q8X5PYV8iuA/6mZj9frDjiePp54B9oh/6fau0gwKVo05hIaRTc2gE3d/WpxfCsgbog2biLh7nha9BaXOwjUmkL53Z2gaXBqGYSkLgCDB/uWp5nXe3p14aaTkVlvtX+51zNdSqD5g2VrCP3H6z1ADYEnyRxQklmi4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=NfGf5ZjC; 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="NfGf5ZjC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3D1ED1F00AC4; Sun, 26 Jul 2026 17:39:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785087589; bh=W5EHzuEPBttna1pHulKblhjSxz0ZvxjVFhC8U+crJAs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=NfGf5ZjCoPczUVUyo2w9UWlRR7cTcOzBj4vEF4PRENKaDmWTXkTty3M54wnKIIj5G widdhobeVKiPvaP0hy3o3TOvF3f122pG42A53/Ndg5BmF9qY+HUb8b39fiXx6zVUGx jiKTniwxzg/35RE0zXe60F5iE6YqGShJTAnJsJTLhBEvn4yrCplWUamNFu8Fz49wz3 wNc5joT+EdngFdatJ/AXkac723R2pgSPmkKAVpx+kUB4r5pkpBjuTyC2YIlqws/mbn ywp6HRHa5v6spJ4f+fK2TIjl5bAHIupbLkkmK2AYuiO8rWBq4pIyG3BoJ2BfG0RLRx qDmSbq26LG37w== 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 v2 15/17] Docs/mm/damon/design: document probe preps Date: Sun, 26 Jul 2026 10:39:31 -0700 Message-ID: <20260726173935.94046-16-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260726173935.94046-1-sj@kernel.org> References: <20260726173935.94046-1-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 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 c4830bd09498d..7f983e0c39b80 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