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=-10.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 044AAC433E0 for ; Thu, 18 Feb 2021 08:56:23 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 5F7C164E76 for ; Thu, 18 Feb 2021 08:56:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5F7C164E76 Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 963CB6B006C; Thu, 18 Feb 2021 03:56:21 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 8EDA76B006E; Thu, 18 Feb 2021 03:56:21 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7B67A6B0070; Thu, 18 Feb 2021 03:56:21 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0236.hostedemail.com [216.40.44.236]) by kanga.kvack.org (Postfix) with ESMTP id 6237E6B006C for ; Thu, 18 Feb 2021 03:56:21 -0500 (EST) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 2EBC9180AD82F for ; Thu, 18 Feb 2021 08:56:21 +0000 (UTC) X-FDA: 77830782162.09.F37A25A Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) by imf30.hostedemail.com (Postfix) with ESMTP id AB905E0011C3 for ; Thu, 18 Feb 2021 08:56:20 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1613638579; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=8RAszh7yrqFMBVVaDFUSTwmQ6Tv/ON0s4M9Tz9qKwYg=; b=VeKsaAxMxonW/fD/t12Ia80ScMOR6LGjZl7eGItzFNo4Yxu2+IDqnAMrfmw/FiXSEbHM3f HXfyeiLxxftUjGZRFMCg1ZCaP3LQ1lj+pif3w2fU6YWXwOLXZk9U1HHbsqhKLtpmujbkIK 1GzcAD728DMOsM6asbmcgSVMLoSjEzY= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 740FFAD87; Thu, 18 Feb 2021 08:56:19 +0000 (UTC) Date: Thu, 18 Feb 2021 09:56:18 +0100 From: Michal Hocko To: Minchan Kim 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: <20210217163603.429062-1-minchan@kernel.org> X-Stat-Signature: 4niho9767mkf3g6rd5sdf3d6h7hb6yz9 X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: AB905E0011C3 Received-SPF: none (suse.com>: No applicable sender policy available) receiver=imf30; identity=mailfrom; envelope-from=""; helo=mx2.suse.de; client-ip=195.135.220.15 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1613638580-746835 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: 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? [...] > @@ -8736,8 +8747,11 @@ struct page *alloc_contig_pages(unsigned long nr_pages, gfp_t gfp_mask, > * and cause alloc_contig_range() to fail... > */ > spin_unlock_irqrestore(&zone->lock, flags); > + > + if (zone_idx(zone) != ZONE_MOVABLE) > + gfp_flags = gfp_mask | __GFP_NOWARN; Nack to this. Caller shouldn't tweak gfp mask of the caller. If we really want to control the reporting based on __GFP_NOWARN or a lack of it then this has to be under control of the caller. > ret = __alloc_contig_pages(pfn, nr_pages, > - gfp_mask); > + gfp_flags); > if (!ret) > return pfn_to_page(pfn); > spin_lock_irqsave(&zone->lock, flags); > -- > 2.30.0.478.g8a0d178c01-goog > -- Michal Hocko SUSE Labs