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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 DC234C33CB2 for ; Tue, 14 Jan 2020 11:02:08 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id A7A1C24679 for ; Tue, 14 Jan 2020 11:02:08 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A7A1C24679 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 424648E0005; Tue, 14 Jan 2020 06:02:08 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 3D3228E0003; Tue, 14 Jan 2020 06:02:08 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2C2348E0005; Tue, 14 Jan 2020 06:02:08 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0113.hostedemail.com [216.40.44.113]) by kanga.kvack.org (Postfix) with ESMTP id 16F538E0003 for ; Tue, 14 Jan 2020 06:02:08 -0500 (EST) Received: from smtpin16.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with SMTP id C704B40F0 for ; Tue, 14 Jan 2020 11:02:07 +0000 (UTC) X-FDA: 76375950294.16.veil20_69ca8c1140507 X-HE-Tag: veil20_69ca8c1140507 X-Filterd-Recvd-Size: 4210 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf15.hostedemail.com (Postfix) with ESMTP for ; Tue, 14 Jan 2020 11:02:06 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E787B142F; Tue, 14 Jan 2020 03:02:05 -0800 (PST) Received: from [10.163.1.192] (unknown [10.163.1.192]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2A9A23F6C4; Tue, 14 Jan 2020 03:02:01 -0800 (PST) Subject: Re: [PATCH] mm/page_alloc: Add a reason for reserved pages in has_unmovable_pages() To: Vlastimil Babka , Michal Hocko Cc: David Hildenbrand , Qian Cai , linux-mm@kvack.org, Andrew Morton , Oscar Salvador , Mel Gorman , Mike Rapoport , Dan Williams , Pavel Tatashin , linux-kernel@vger.kernel.org, Ralph Campbell References: <49fa7dea-00ac-155f-e7b7-eeca206556b5@arm.com> <6A58E80B-7A5F-4CAD-ACF1-89BCCBE4D3B1@lca.pw> <20200114091013.GD19428@dhcp22.suse.cz> <1f3ff7fc-2f6b-d8e5-85a5-078f0e1a0daf@suse.cz> From: Anshuman Khandual Message-ID: Date: Tue, 14 Jan 2020 16:33:19 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <1f3ff7fc-2f6b-d8e5-85a5-078f0e1a0daf@suse.cz> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit 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 01/14/2020 03:53 PM, Vlastimil Babka wrote: > On 1/14/20 10:10 AM, Michal Hocko wrote: >> [Cc Ralph] >>> The reason is dump_page() does not print page->flags universally >>> and only does so for KSM, Anon and File pages while excluding >>> reserved pages at boot. Wondering should not we make printing >>> page->flags universal ? >> >> We used to do that and this caught me as a surprise when looking again. >> This is a result of 76a1850e4572 ("mm/debug.c: __dump_page() prints an >> extra line") which is a cleanup patch and I suspect this result was not >> anticipated. >> >> The following will do the trick but I cannot really say I like the code >> duplication. pr_cont in this case sounds like a much cleaner solution to >> me. > > How about this then? This looks better than what we have right now though my initial thought was similar to what Michal had suggested earlier. > > diff --git mm/debug.c mm/debug.c > index 0461df1207cb..6a52316af839 100644 > --- mm/debug.c > +++ mm/debug.c > @@ -47,6 +47,7 @@ void __dump_page(struct page *page, const char *reason) > struct address_space *mapping; > bool page_poisoned = PagePoisoned(page); > int mapcount; > + char *type = ""; > > /* > * If struct page is poisoned don't access Page*() functions as that > @@ -78,9 +79,9 @@ void __dump_page(struct page *page, const char *reason) > page, page_ref_count(page), mapcount, > page->mapping, page_to_pgoff(page)); > if (PageKsm(page)) > - pr_warn("ksm flags: %#lx(%pGp)\n", page->flags, &page->flags); > + type = "ksm "; > else if (PageAnon(page)) > - pr_warn("anon flags: %#lx(%pGp)\n", page->flags, &page->flags); > + type = "anon "; > else if (mapping) { > if (mapping->host && mapping->host->i_dentry.first) { > struct dentry *dentry; > @@ -88,10 +89,11 @@ void __dump_page(struct page *page, const char *reason) > pr_warn("%ps name:\"%pd\"\n", mapping->a_ops, dentry); > } else > pr_warn("%ps\n", mapping->a_ops); > - pr_warn("flags: %#lx(%pGp)\n", page->flags, &page->flags); > } > BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS + 1); > > + pr_warn("%sflags: %#lx(%pGp)\n", type, page->flags, &page->flags); > + > hex_only: > print_hex_dump(KERN_WARNING, "raw: ", DUMP_PREFIX_NONE, 32, > sizeof(unsigned long), page, > >