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 X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C03C3C433DB for ; Thu, 18 Feb 2021 18:35:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7A73A64E92 for ; Thu, 18 Feb 2021 18:35:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231951AbhBRSe4 (ORCPT ); Thu, 18 Feb 2021 13:34:56 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39416 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233135AbhBRQLR (ORCPT ); Thu, 18 Feb 2021 11:11:17 -0500 Received: from mail-pf1-x432.google.com (mail-pf1-x432.google.com [IPv6:2607:f8b0:4864:20::432]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1DBE0C061794 for ; Thu, 18 Feb 2021 08:10:33 -0800 (PST) Received: by mail-pf1-x432.google.com with SMTP id j12so1580909pfj.12 for ; Thu, 18 Feb 2021 08:10:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=k/RqDGUNhoNYq3IBZ52eaMQt2gjuVi91yB+Zi9HnIoY=; b=I7rUmNQljY9Jk3djbiDNOojkc4eoNilxIHJ9KUKZjvQsEC0jDer5M0cwdhn8w24b5m 09ZQ0M6lt/GZj1TS8gbFpixow3S6hEMrr2fOrhpD8huHouISOOzDP3WdkMpWDD1BsagS sH/A10O8Ge9LOuuAgJoB28xuhnU8rhUy/sMIiB4IarNb1naKc++OA/Ul8naCmFlyoYhI wSv1QW6MLe8opogR82YsgCwa7q97jbryIxqP8a/xO1ZpWtx9A/xTuwY92ogpU8OKpYNV x3+8WcNebObNrO4Sp9QeQOI7z1bqUQmI2fT1xpwHVV56N+lXwSAp9mR5vPU0otMPc5xj AtJA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=k/RqDGUNhoNYq3IBZ52eaMQt2gjuVi91yB+Zi9HnIoY=; b=M3Vh2KE0Du0keepJL8wzsBIwcUzYiztadTlyHYova/NJfqUyWe3B8+yBPmGMmDMz/N x8tHoN5X0fn1PVW5+T7/ftOuA6lnuWwnSkzFEtKL35oxjlsrrp3vVKnggQskAzqOZcEf rzz5kM20W6nrG7uVkRlnEOf+mKamt9C4xGVISSC8yhD7mPnsSLVk9BzGMHhJnYhY+fqm A3y+m4DMSQlOdAj9XzIAmoOFG94DDyl4wWnFAG5GqSJCem+4kW27bwjmeFz2YD3UVDpg 4AYPPrIOeqCxitbhKy3m61qzUEkwDwOh0OXPJzZKWojLGYWbvZ7Ft78pbZ+KnSJRvKI7 GUdw== X-Gm-Message-State: AOAM531nVPMlY0i1XtITh6AsDxWgGfojpamQFIKUjPxawwdGFT+WwH7+ i1hAskvJayHYiQOeKmM95V4= X-Google-Smtp-Source: ABdhPJxzK3s1aFvwRizRfxBz5x8pjjKoHWjP2ahug80JQzM2nsD4pay2JZfUjYxQB7yKwELPepy1Kw== X-Received: by 2002:a65:458e:: with SMTP id o14mr4517255pgq.444.1613664633349; Thu, 18 Feb 2021 08:10:33 -0800 (PST) Received: from google.com ([2620:15c:211:201:157d:8a19:5427:ea9e]) by smtp.gmail.com with ESMTPSA id g62sm6876628pgc.32.2021.02.18.08.10.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 18 Feb 2021 08:10:32 -0800 (PST) Sender: Minchan Kim Date: Thu, 18 Feb 2021 08:10:30 -0800 From: Minchan Kim To: Michal Hocko Cc: Andrew Morton , linux-mm , LKML , david@redhat.com, joaodias@google.com Subject: Re: [PATCH] mm: be more verbose for alloc_contig_range faliures Message-ID: References: <20210217163603.429062-1-minchan@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Feb 18, 2021 at 09:56:18AM +0100, Michal Hocko wrote: > On Wed 17-02-21 08:36:03, Minchan Kim wrote: > > alloc_contig_range is usually used on cma area or movable zone. > > It's critical if the page migration fails on those areas so > > dump more debugging message like memory_hotplug unless user > > specifiy __GFP_NOWARN. > > I agree with David that this has a potential to generate a lot of output > and it is not really clear whether it is worth it. Page isolation code > already has REPORT_FAILURE mode which currently used only for the memory > hotplug because this was just too noisy from the CMA path - d381c54760dc > ("mm: only report isolation failures when offlining memory"). > > Maybe migration failures are less likely to fail but still. Doesn't CMA > allocator provide some useful error reporting on its own? Unfortunately, it's very useless. :( ``` in cma.c pr_debug("%s(): memory range at %p is busy, retrying\n", __func__, pfn_to_page(pfn)); ``` even, the pfn is not failed page. Originally, I thought to deal with it from cma.c to minimize changes but it was tough because cma area couldn't get the failed page list.