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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 387EFC433EF for ; Fri, 15 Apr 2022 05:31:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346199AbiDOFd3 (ORCPT ); Fri, 15 Apr 2022 01:33:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50978 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344938AbiDOFd1 (ORCPT ); Fri, 15 Apr 2022 01:33:27 -0400 Received: from mail-vs1-xe31.google.com (mail-vs1-xe31.google.com [IPv6:2607:f8b0:4864:20::e31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D5CDBA146B for ; Thu, 14 Apr 2022 22:30:59 -0700 (PDT) Received: by mail-vs1-xe31.google.com with SMTP id i186so6306601vsc.9 for ; Thu, 14 Apr 2022 22:30:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=Di+wr37U174Nx7w1oJa4ec3u7LAPibr5Hnogm0KQ5KA=; b=HODn7qI57pWt1oZWbQMZ3KJCt8UgF2sxF84uj3uKTo3R6eblGW4tKzonTWLm1pEFdT yG9qgeECK1ytcgWBIg43CscdMBJJAqPOA/zudzK/VTJyN7Vn4jq64VvB4EJTnAZo3xU9 /tb4RBVKtNQnhCk9Nn4nDf8REhxVQGZ3TELX0jzmRqP/qaadUEj34ceL3HKuezdZsDUe YTq0cKMpvi3RGvjGlu/xtA4UgmNAeKG314EWDEPQ1nRXokxz3VfBJi+o4W1eH6Mh1eCE eCX8cIYTJ7tq19cO4pn1Wugsac81ETz55D5v4+CV4PJwbUYIakUlvJirdXAygbmf1Kv6 W/Dw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=Di+wr37U174Nx7w1oJa4ec3u7LAPibr5Hnogm0KQ5KA=; b=cGmUDkpB+8hfpFn2blbNeNLJ5M0BJUrlfMhB3tztnjlyaN0NIAs1t7abmG4nBJSFzA 0w4WGXb1tcepUq/sz/tYqw1a4ZFq6EtFK/99ucyoZEMzRhSclpRsYygyseWaesuojgme jJlcJsCVMOsyGv9FETqshYLEExM34MMJsCZswGPIlLVwSe2q5hSgfI6vRqaqf8q6D/1Z tAd1vs5Eiiw2YuIYo0i4Da/zalzanps87qtlzzSaSEdrGKhqwONBrg4zJani063KtsaD fUQbhkGquVAzBwIsg3GztsxKOmSM+HIfuV78PdVwVtgRH8ILwwvj7y8R51xhrZ07JW1V y6Ww== X-Gm-Message-State: AOAM533gfTz1TiEK+9BFWmzIgNDI9O6l2fK93daxOC4Fha3+idqgyKTa EOWHIoVgRfQvsfx8f2ppoeXIUKNTXNzQtVtDXLyljQ== X-Google-Smtp-Source: ABdhPJz/nQA8xxiMNDyTW4PUrlucKA7LqqG3BlyYwzZ4ZVXZvD8oivYN5l/8PMooP8q1SwXigPcaj8U6TIwW9K1TzWs= X-Received: by 2002:a05:6102:5cc:b0:320:9bd2:3823 with SMTP id v12-20020a05610205cc00b003209bd23823mr2650275vsf.81.1650000658866; Thu, 14 Apr 2022 22:30:58 -0700 (PDT) MIME-Version: 1.0 References: <20220407031525.2368067-1-yuzhao@google.com> <20220407031525.2368067-9-yuzhao@google.com> <20220411191621.0378467ad99ebc822d5ad005@linux-foundation.org> <20220412071026.GU2731@worktop.programming.kicks-ass.net> In-Reply-To: <20220412071026.GU2731@worktop.programming.kicks-ass.net> From: Yu Zhao Date: Thu, 14 Apr 2022 23:30:22 -0600 Message-ID: Subject: Re: [PATCH v10 08/14] mm: multi-gen LRU: support page table walks To: Peter Zijlstra Cc: Andrew Morton , Stephen Rothwell , Linux-MM , Andi Kleen , Aneesh Kumar , Barry Song <21cnbao@gmail.com>, Catalin Marinas , Dave Hansen , Hillf Danton , Jens Axboe , Jesse Barnes , Johannes Weiner , Jonathan Corbet , Linus Torvalds , Matthew Wilcox , Mel Gorman , Michael Larabel , Michal Hocko , Mike Rapoport , Rik van Riel , Vlastimil Babka , Will Deacon , Ying Huang , Linux ARM , "open list:DOCUMENTATION" , linux-kernel , Kernel Page Reclaim v2 , "the arch/x86 maintainers" , Brian Geffon , Jan Alexander Steffens , Oleksandr Natalenko , Steven Barrett , Suleiman Souhlal , Daniel Byrne , Donald Carr , =?UTF-8?Q?Holger_Hoffst=C3=A4tte?= , Konstantin Kharlamov , Shuang Zhai , Sofia Trinh , Vaibhav Jain Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 12, 2022 at 1:10 AM Peter Zijlstra wrote: > > On Mon, Apr 11, 2022 at 07:16:21PM -0700, Andrew Morton wrote: > > On Wed, 6 Apr 2022 21:15:20 -0600 Yu Zhao wrote: > > > > +#ifdef CONFIG_LRU_GEN > > > +static void mem_cgroup_attach(struct cgroup_taskset *tset) > > > +{ > > > + struct cgroup_subsys_state *css; > > > + struct task_struct *task = NULL; > > > + > > > + cgroup_taskset_for_each_leader(task, css, tset) > > > + break; > > > > Does this actually do anything? > > Yeah, it finds the first leader if there is any, but this is indeed > quite terrible coding style. I've added a one liner comment "find the first leader if there is any", for now. I'm open to other suggestions.