From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6A6BBD116F3 for ; Mon, 1 Dec 2025 21:35:27 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B91176B00AF; Mon, 1 Dec 2025 16:35:26 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id B68D96B00B1; Mon, 1 Dec 2025 16:35:26 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id AA5AE6B00B2; Mon, 1 Dec 2025 16:35:26 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0015.hostedemail.com [216.40.44.15]) by kanga.kvack.org (Postfix) with ESMTP id 9A98C6B00AF for ; Mon, 1 Dec 2025 16:35:26 -0500 (EST) Received: from smtpin14.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id 4CA601320CC for ; Mon, 1 Dec 2025 21:35:26 +0000 (UTC) X-FDA: 84172208652.14.9C6CCC3 Received: from mail-pl1-f177.google.com (mail-pl1-f177.google.com [209.85.214.177]) by imf03.hostedemail.com (Postfix) with ESMTP id 60C0A20013 for ; Mon, 1 Dec 2025 21:35:24 +0000 (UTC) Authentication-Results: imf03.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=CkmbJDLE; spf=pass (imf03.hostedemail.com: domain of yuanchu@google.com designates 209.85.214.177 as permitted sender) smtp.mailfrom=yuanchu@google.com; dmarc=pass (policy=reject) header.from=google.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1764624924; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=pztwMSM/xJ8ORFd02azXUTlR9KBkGnFnYMXGWY/ok94=; b=ULLRRvFx+mw3n7OOrCtJeYemUQco0czBoCH4ZJdg0BCvSbpihqGXtfUFYi1LrQmGVi/x8T Z3TaqvgqitjULR8vnCcXuJZKNbQX0chhPXJfOBMgaRiI/7H9SGlFrLz04bxfM/zXVF8wuy nJu4n1XvI271uDxBcERmoGmJZHAxEwU= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1764624924; a=rsa-sha256; cv=none; b=jJ/4B4/1xvJbiRCxnmnc0rnIjVunrP6AQPbY7rbSbyMynBLmfcFm+MUMHgXh4vGgrneFox kOtR/QdknrdJDE38uZNxTwpDdNAhw3KBNVGvrvVmex3JKQ1ykQWHbu5BiQsRmA3HWCPapy DE84jrS04vBFDs4nVDDwY/XLE6+FlUQ= ARC-Authentication-Results: i=1; imf03.hostedemail.com; dkim=pass header.d=google.com header.s=20230601 header.b=CkmbJDLE; spf=pass (imf03.hostedemail.com: domain of yuanchu@google.com designates 209.85.214.177 as permitted sender) smtp.mailfrom=yuanchu@google.com; dmarc=pass (policy=reject) header.from=google.com Received: by mail-pl1-f177.google.com with SMTP id d9443c01a7336-29852dafa7dso839805ad.1 for ; Mon, 01 Dec 2025 13:35:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1764624923; x=1765229723; darn=kvack.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=pztwMSM/xJ8ORFd02azXUTlR9KBkGnFnYMXGWY/ok94=; b=CkmbJDLEJht6kUguLSpirO1GKUuiZ/1B2doMXzvQiT03LAQMXFEwPTrI8xM5+Ph70i BGpS0nJRvai31er/AOckYC02XiYox5OlwzcgJmQXSgpO8ZJzwhcJUjQ0I8SviXmEhfpc h1TrSVjBdNr7h2jgmn/8OMLhUaLVLDvLJTimYPIGf+0+9emQxED/CU9hJu6diOJ0Cezm MAr28dPdVQ8QtIfzWS41zQFrSrauN9taFKw99jw5EHGsH2NnGDrcls1swpWkU68Yvz8h +ECqnXi//5YMokMzDzcA73cnnopOQlrHUCTt05OyEZU8wWSLIvRhVN9Ctmml+AyuyzCu MTZg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1764624923; x=1765229723; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=pztwMSM/xJ8ORFd02azXUTlR9KBkGnFnYMXGWY/ok94=; b=iK/vDMoRKTx8MmGe4OiFjz82tpds+E7NHRqhM4rMMdewMjZFraxPQa3U/46Qf2cwpq U2Y7Pan5fCJqPWm5AYWZV4xsnyJt/4uenwxdirOFXou5e3kJ9NbUmwMLgiDZ2ZWxSISc pJiUk9cpYsKLNDpawoLd1rKFqOmT9BgJ3QXB6HK33uWvI5/yhhV3akLrWxqskn40s5+t d1X70l+cM7jfUF3jCZgwzNTZPKHx8XCC6G1dZdVd/FRDUHdHLRku/eKxVrPBhk+2mKBt Z+A8Y9BzvL9F4Oafyxf6lS8YdFTM7siP5Q1jRutgF8d7SMxhBu3hWOLV2aNpXS5Y4mNR 8KRw== X-Forwarded-Encrypted: i=1; AJvYcCU8uOsv5yuKuJLOLSirTiC+B1ZB1sIzJJXTDcbEbYiO8EwGp1Y8+9ELXXa9kGEIDgKd+zSSMTARzA==@kvack.org X-Gm-Message-State: AOJu0Yyr2nILtAvvZVZTB9dRowhYYfYk5HN55tCyPPXdR0U4wBI54IAi YvvGQCdzxI98m8X4ilW+WdLPdkzuTpMCrfPGRJ3MkwnBuVPE6b947eeK/1pf47XdSIV1DkqHxK4 6gJ15x1nXJRg417mThVBDLCFFQeOzOSMgqK9qKEov X-Gm-Gg: ASbGncvtHefzVjEB3cNb2egkfukzTMZr6zOi32n44B1fxeQv8AJF/K0pVkP5cbLipxR XubvmopPCboYZH9KYPN9UbSnjk/HWHdBCPeRsXWtt3KXyBIWdtIqvQ4AIEgUdQPwK5ptIUqbk8O Lsun53i7HI+DvzAXzzYambHIHe+ILp7A125B4ftjkcJ37S2gD11GFC+9pkASVNs1N7chciliifQ Fq/eD82IPwGsve1KLVlZ0FxRNW/EA88R7Pp6/9HiEHPheQUczEG0D4kvxSgNc94YCF5TZ4WEWus 7sa8vOI/uNWk5bN3dctSBTJtAeYlAL0oez4m X-Google-Smtp-Source: AGHT+IGcEr+u4Lvyu2lcr5/u3UATd1g0adlZD8heHy4ha30xHQDJbp7Oka+Ww5wtit5evGdRnPc0wgduqHEKGAIhdio= X-Received: by 2002:a05:7022:6190:b0:11a:4c75:a45b with SMTP id a92af1059eb24-11de93975a9mr2477c88.10.1764624921927; Mon, 01 Dec 2025 13:35:21 -0800 (PST) MIME-Version: 1.0 References: <20251128025315.3520689-1-wangzicheng@honor.com> <20251128025315.3520689-3-wangzicheng@honor.com> In-Reply-To: <20251128025315.3520689-3-wangzicheng@honor.com> From: Yuanchu Xie Date: Mon, 1 Dec 2025 15:35:05 -0600 X-Gm-Features: AWmQ_bnUvWHfjLPC5vTcuKxCijZrgA-YfCUFmk-n0mUVC2U4d1FBt5FslZMBSHs Message-ID: Subject: Re: [PATCH 2/3] mm/lru_gen: add configuration option to select debugfs/procfs for lru_gen To: Zicheng Wang Cc: akpm@linux-foundation.org, hannes@cmpxchg.org, david@redhat.com, axelrasmussen@google.com, mhocko@kernel.org, zhengqi.arch@bytedance.com, shakeel.butt@linux.dev, lorenzo.stoakes@oracle.com, weixugc@google.com, Liam.Howlett@oracle.com, vbabka@suse.cz, rppt@kernel.org, surenb@google.com, mhocko@suse.com, corbet@lwn.net, linux-mm@kvack.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 60C0A20013 X-Stat-Signature: x7sp7ubwzsh8zzjdrmz7cjzore5hefo6 X-Rspam-User: X-HE-Tag: 1764624924-442647 X-HE-Meta: U2FsdGVkX18g+TvgN0vmcN4paRIfC+Odp1QimS7gysKKhI/+d8rlrqbpE4edhvj4qWhjXtkVKdrSkmJteuGulSzt+9LmHHvsuHEh/ZHdl5Io4a0NIS7cu31/TOIPSnZTooD8Ufki9OhCVJC/reTF8LIOb0buvDNt0d+aT4SoQPGRnZW3dlUBnGdgJjLEhTrXH9L8YODnBrFKV7HyYDDeyHVmqCHAnQ5paojG+0X9mT5PbP6BB9tcB9J70tMzG8Bgcb+ZrGBQ5r3ZF/O7Cf+PzzgsWkQhak53Sb8UHqKJGqInnKtEtDhe26H8nsOULoSsdohFygL01TrTTtb5mEjwkOOhhQ2/1Z2fwtMz9ciYgoEpUJn7VngorYqMtDk3w2lLG2BI4KLfdJudTowe3hZQyBO9sosDCcBftHBZ/ksJJzQWdVp1SM8k0564aJ9vp26STeuDUoXCrkQ0+95pVi4BNv/8kwedW2AG1VUT4QB9Gbl7ZcintqC0dwirCpg506k69SDd0NjWzAQq9RRdOeq86L68IMEhGeQmnvqrq2NTMVfq6stUhVCStnKAjXjITlZ1T9Icx0SYLyuUyXT6q4Otcvpor7UkxgsINFw78omKDx4laIoOUtY5NUAq9LNMYmfWK97Ck5a6lQYJ3mCfytiIiQ9z46T/wMXBg96Cj0Bvior+IQpOhdoQ+8QYxYpIZMkJ6eViUPqoZcjZtj/mAoykL9ZbgDn9Vryuz542KSLeh4JocEzE+SFuUDLacTp85VFoaAkh7Th6gZ0558ZStNB05N+zS29Ly08Rvdxbe7YglUlx4AS0Ee6ECNnhDJKYVDGs4G7py+eT2Knl2Vwc18g6AWju0UvGIPy6ue2j++ujP5oHgkhSnkWibP8smsLjcvKnj9Tabm3WycCOpBDC5qBdsw/Q2FRNeuuC1vLLUfK5UjmDDSw7bqyjhOuWC1HurhUiTQLNkN/E99LbgU9wqrn 2IJTpL87 yK0yV9TST64ZyAtru/SoEGbstAJO9UXSFBZ3KBXkI4NS0LYABLd3ViQykBgEXwz19XCoH8PZb4Zx7jP0I3bBuoWs1TBaMQD6GozUM+7wGk4uOgSpu2eeLkLOg8S2RpRscNKdg129mrt43MCMIUcr4qxL2Wz0oKFtDUhMKKV+Fy8ddypwzXvhg23NbGvgw9sJjtLZEEv2SsB/R52z4katqsFdQVQYXte/sxUzO7LJTwze6ibT+3BPDG4CsoAOrMR2BUNqfCZTI5JcOtvAp/W3LKPKyCJu62VsBWm3nKrcmzTSmO/Y= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Thu, Nov 27, 2025 at 8:54=E2=80=AFPM Zicheng Wang wrote: > > Signed-off-by: Zicheng Wang > --- > mm/Kconfig | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/mm/Kconfig b/mm/Kconfig > index e443fe8cd..be7efa794 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -1325,6 +1325,16 @@ config LRU_GEN_STATS > config LRU_GEN_WALKS_MMU > def_bool y > depends on LRU_GEN && ARCH_HAS_HW_PTE_YOUNG > + > +config LRU_GEN_PROCFS_CTRL > + bool "Move lru_gen files from debugfs to procfs" > + depends on LRU_GEN && PROC_FS > + help > + Move lru_gen management from debugfs to procfs (/proc/lru_gen). > + This production-ready feature provides critical memory reclaim > + prediction and control. It is no longer experimental. > + The migration ensures availability in commercial products where > + debugfs may be disabled. Hi Zicheng, A config option determining where LRU_gen files reside creates a fragile procfs interface. Consider adding a similar interface with less implementation detail to /sys/kernel/mm/lru_gen/ if the goal is to stabilize the debugfs APIs. If the goal is to proactively age lruvecs that have been at MIN_NR_GENS for some time/events/etc, is it possible to integrate this into the kernel and avoid leaking MGLRU implementation details into userspace? Thanks, Yuanchu