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=-6.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 88A15C433DF for ; Tue, 13 Oct 2020 23:55:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4DAA322227 for ; Tue, 13 Oct 2020 23:55:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602633327; bh=yu/DceDmp5i31UTmOfwgiA22IilT5cSSBYIfR/R+QYQ=; h=Date:From:To:Subject:In-Reply-To:Reply-To:List-ID:From; b=ZLDHZsp+NFn9zUe+8GnLP21BPm4+LfMYHhbOsLPGPBht2CJODHYoQ2qUQfo2kschb EYiPxUtvJPHw/3Ztdk45ouqNiY/rplWQiGd/oOuuldnKpj9C3OaBtJNt4TSX4ws5bv sT5ptyfSvGSAxMuAQywaB97ObMns03zS0EpNDP5A= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388437AbgJMXz1 (ORCPT ); Tue, 13 Oct 2020 19:55:27 -0400 Received: from mail.kernel.org ([198.145.29.99]:40774 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388436AbgJMXz0 (ORCPT ); Tue, 13 Oct 2020 19:55:26 -0400 Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 02A13221FF; Tue, 13 Oct 2020 23:55:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602633325; bh=yu/DceDmp5i31UTmOfwgiA22IilT5cSSBYIfR/R+QYQ=; h=Date:From:To:Subject:In-Reply-To:From; b=2gy5G6sPJjjB5+2W/q3mwgACdJNYCfWZtuOBHtriEaxY6wV2xb2nBCHQk06Ilmnsb xHTOCdMeGg2pvpmfSSTrvOPVY/2p+9uQstl7qbKk0SxP0/RqvnturQIL3ofG3Twcj/ zBnOqy6a0zEkP2DqFzzIP7iu4iZf/tnoCkjJOtMI= Date: Tue, 13 Oct 2020 16:55:24 -0700 From: Andrew Morton To: akpm@linux-foundation.org, bhe@redhat.com, cai@lca.pw, david@redhat.com, jasowang@redhat.com, linux-mm@kvack.org, mhocko@suse.com, mike.kravetz@oracle.com, mm-commits@vger.kernel.org, mst@redhat.com, pankaj.gupta.linux@gmail.com, rppt@kernel.org, torvalds@linux-foundation.org Subject: [patch 127/181] mm/page_isolation: drop WARN_ON_ONCE() in set_migratetype_isolate() Message-ID: <20201013235524.VLOo7GrME%akpm@linux-foundation.org> In-Reply-To: <20201013164658.3bfd96cc224d8923e66a9f4e@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: David Hildenbrand Subject: mm/page_isolation: drop WARN_ON_ONCE() in set_migratetype_isolate() Inside has_unmovable_pages(), we have a comment describing how unmovable data could end up in ZONE_MOVABLE - via "movablecore". Also, besides checking if the first page in the pageblock is reserved, we don't perform any further checks in case of ZONE_MOVABLE. In case of memory offlining, we set REPORT_FAILURE, properly dump_page() the page and handle the error gracefully. alloc_contig_pages() users currently never allocate from ZONE_MOVABLE. E.g., hugetlb uses alloc_contig_pages() for the allocation of gigantic pages only, which will never end up on the MOVABLE zone (see htlb_alloc_mask()). Link: http://lkml.kernel.org/r/20200816125333.7434-4-david@redhat.com Signed-off-by: David Hildenbrand Reviewed-by: Baoquan He Cc: Michal Hocko Cc: Michael S. Tsirkin Cc: Mike Kravetz Cc: Pankaj Gupta Cc: Jason Wang Cc: Mike Rapoport Cc: Qian Cai Signed-off-by: Andrew Morton --- mm/page_isolation.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) --- a/mm/page_isolation.c~mm-page_isolation-drop-warn_on_once-in-set_migratetype_isolate +++ a/mm/page_isolation.c @@ -57,15 +57,12 @@ static int set_migratetype_isolate(struc spin_unlock_irqrestore(&zone->lock, flags); if (!ret) { drain_all_pages(zone); - } else { - WARN_ON_ONCE(zone_idx(zone) == ZONE_MOVABLE); - - if ((isol_flags & REPORT_FAILURE) && unmovable) - /* - * printk() with zone->lock held will likely trigger a - * lockdep splat, so defer it here. - */ - dump_page(unmovable, "unmovable page"); + } else if ((isol_flags & REPORT_FAILURE) && unmovable) { + /* + * printk() with zone->lock held will likely trigger a + * lockdep splat, so defer it here. + */ + dump_page(unmovable, "unmovable page"); } return ret; _