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 57414388E62; Tue, 28 Jul 2026 04:12:58 +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=1785211981; cv=none; b=enRNgROkEZVpvkEFzO3FdfnzWPNiioN56dSYY1eMRsi/ZLaqlKBcXUEMX7WY/oGFmcJMjmoM4tCq706cnO2CZdwkHIB9mjtOJXPDTXNKHYBbpmrFU6QRiOHz7UmkB71IJzllnQzbRgrgnp877M8Jz6Tc8vhl0tfxzIertDnRGU8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785211981; c=relaxed/simple; bh=xcWvcxTShuREolgVeaNKxOb9JPpBPwIcsH+2uXlYsDc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=iypS9u1WBJWtBZZ5czCkToDYpaEcf03JBIOFrHCNNHgrr9dtrLb/7W1s7lmJ0msCmMM0N/E33uNEWWFxZCpVhq7gbMXX+uoI6DMcwq19KhEiCH5UYfwg2Ku8wQoqUDhR+QiTrR4hxQ1pMTZiO8k1QnqPAe8q36G7iZsSaDFaELw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=NCRNd9zy; 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="NCRNd9zy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 18EF91F0155B; Tue, 28 Jul 2026 04:12:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785211977; bh=W5EHzuEPBttna1pHulKblhjSxz0ZvxjVFhC8U+crJAs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=NCRNd9zyj03vt8HhyG/dRw2Jd/KNZwx5JqnVm51nuuNO6R7PxTNgwXbVh0dyaN6aU xZeOoBOnDTH8OScjrOHujJd2sRPOR52mPne/5+zmMLyzJV4eit8qIFfUqzkF8BcD8Z nAnnWnJ2vT5Eyn2pQmbvfsa/53don3XRdMdT1Zp8LrtaCkdh8zMbGeJI05tSigWx/Z SEl02vzaT0SuUOksTou01bAN7s+nt9d8nzgT3KmoIoTcStvxzNzAbfAgKXK5HV3ibB JyVXT8C/YGDzUufUpRn6OaFvpGZUsq7UHszKtoQDWRx9+ugto1lR6j1rhfSk+dl7X1 ItxxlmphMOafg== 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 v2.2 15/17] Docs/mm/damon/design: document probe preps Date: Mon, 27 Jul 2026 21:12:36 -0700 Message-ID: <20260728041242.187380-16-sj@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260728041242.187380-1-sj@kernel.org> References: <20260728041242.187380-1-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 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