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 71DC03C4176; Fri, 11 Sep 2026 11:32:19 +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=1789126354; cv=none; b=jjC8G8GrQJHy/e0tsiGGN88lTiEmi33EYaTwY2fhEXjIG7u1HrIVgsXG3hl43LBY36j2AoAHmvRoHWyu8/hlcC786ykRd3bQRXUwUf15wwOQFnnWHSSFaLuL57JN2R8P61/3pl9DmUr1RUT+5Mz7Qe7WhUdQDZv8TnJqm+wU6+4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789126354; c=relaxed/simple; bh=mcwyVbWOJ/TfKmQoQX0l+SJ37BAG5DpRv7tbIYppDXI=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=HYV3WwEmAo3S2CadhuuSR6U+4bRiFC0OnbXigGBQcESWAwKWwvMTIoZTcgpNcHbj8m2q/Y+ZSIdm07fi+YTXDVH1DY8DwyMKWmdZ18SUnSjkSqS3/P5I8u/3nWW8cnIERTTgXOXGk+7VvQ+jdHZaQq72D5Df0lcChzS+BK1v8FM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ngM6IP5I; 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="ngM6IP5I" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7DC751F000FF; Fri, 11 Sep 2026 11:32:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1789126336; bh=mcwyVbWOJ/TfKmQoQX0l+SJ37BAG5DpRv7tbIYppDXI=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=ngM6IP5Ips1PcyuAaKQbkTNILTCi2yDow4kz88XMamK6hQFrzuA/ESPzyS15dRNbw FdmWJsmFkS9jr6N08h2gs/F3PaZPuZy17cbKN9gZCCvBPtGmHPOR5WqHGMbM1iAcUZ NQ4r3k53OB3+Q+fPnQK9UrYKubf3EN+9cILPUQ7k9qlBmQ/s64uSpA/sp/ohSiVFPZ wdrRH6e0np+Db0X33f+GJ39tvmT/ogqM8iLLHiV4P509K2Qdx6kxH1uMTifIVjkvs5 p1e3ZDZ+YAuHokDI60IrEgub3Letiv6f3QEpSVAuPRbmp6ESv9FuSTlyEydhvTspWD jhxYV0ocEITcw== Date: Fri, 11 Sep 2026 12:32:09 +0100 From: "Lorenzo Stoakes (ARM)" To: "David Hildenbrand (Arm)" Cc: "zhen.ni" , Zi Yan , Andrew Morton , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jonathan Corbet , Shuah Khan , Randy Dunlap , Brendan Jackman , Johannes Weiner , linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3 0/8] mm/page_owner: Add PID/TGID/COMM and cgroup filtering Message-ID: References: <20260907082620.2083838-1-zhen.ni@easystack.cn> <79548641-25f3-4ec3-a549-782fad168962@kernel.org> <6e8bfb0d-d595-4e6b-9536-0323ada57e25@easystack.cn> <22D1EC4B-FBCB-421E-B8DA-345B5F3505FB@nvidia.com> <98ca914b-4722-448d-b5a4-7f095d0ca433@kernel.org> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <98ca914b-4722-448d-b5a4-7f095d0ca433@kernel.org> On Fri, Sep 11, 2026 at 01:06:46PM +0200, David Hildenbrand (Arm) wrote: > On 9/11/26 09:58, zhen.ni wrote: > > > > > > 在 2026/9/9 23:54, Zi Yan 写道: > >> On 9 Sep 2026, at 6:28, David Hildenbrand (Arm) wrote: > >> > >>> > >>> Because it results in less kernel code  :) > >>> > >>> And less kernel code is good. Unless unavoidable. > >> > >> An alternative is to add BPF hooks like bpf_iter to do the filtering > >> and by default, when no BPF program is attached, everything is printed. > >> > >> > > > > I’ve also thought about a similar approach—perhaps a new bpf_iter type > > that could iterate over all pages by PFN. The advantage would be that > > you can fully customize what you want to print and what you want to > > filter. However, doing so would require refactoring the entire > > page_owner, and I’m not sure whether it’s worth pursuing in this > > direction.I’d also like to hear everyone’s thoughts on this. > > Certainly better than having more and more manual filters added to the code base. Agreed. bpf seems the ideal fit here I think? Means that those who want this information can get it and those who don't are unaffected. > > -- > Cheers, > > David -- Cheers, Lorenzo