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=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 AAE6BC28CF8 for ; Thu, 11 Oct 2018 22:17:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 73664213A2 for ; Thu, 11 Oct 2018 22:17:00 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 73664213A2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727071AbeJLFqP (ORCPT ); Fri, 12 Oct 2018 01:46:15 -0400 Received: from mga17.intel.com ([192.55.52.151]:13924 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726072AbeJLFqO (ORCPT ); Fri, 12 Oct 2018 01:46:14 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 11 Oct 2018 15:16:56 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,370,1534834800"; d="scan'208";a="80765705" Received: from ahduyck-mobl.amr.corp.intel.com (HELO localhost.localdomain) ([10.7.198.157]) by orsmga008.jf.intel.com with ESMTP; 11 Oct 2018 15:13:51 -0700 Subject: [mm PATCH v2 4/6] mm: Do not set reserved flag for hotplug memory From: Alexander Duyck To: linux-mm@kvack.org, akpm@linux-foundation.org Cc: pavel.tatashin@microsoft.com, mhocko@suse.com, dave.jiang@intel.com, alexander.h.duyck@linux.intel.com, linux-kernel@vger.kernel.org, willy@infradead.org, davem@davemloft.net, yi.z.zhang@linux.intel.com, khalid.aziz@oracle.com, rppt@linux.vnet.ibm.com, vbabka@suse.cz, sparclinux@vger.kernel.org, dan.j.williams@intel.com, ldufour@linux.vnet.ibm.com, mgorman@techsingularity.net, mingo@kernel.org, kirill.shutemov@linux.intel.com Date: Thu, 11 Oct 2018 15:13:51 -0700 Message-ID: <20181011221351.1925.67694.stgit@localhost.localdomain> In-Reply-To: <20181011221237.1925.85591.stgit@localhost.localdomain> References: <20181011221237.1925.85591.stgit@localhost.localdomain> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The general suspicion at this point is that the setting of the reserved bit is not really needed for hotplug memory. In addition the setting of this bit results in issues for DAX in that it is not possible to assign the region to KVM if the reserved bit is set in each page. For now we can try just not setting the bit since we suspect it isn't adding value in setting it. If at a later time we find that it is needed we can come back through and re-add it for the hotplug paths. Suggested-by: Michael Hocko Reported-by: Dan Williams Signed-off-by: Alexander Duyck --- mm/page_alloc.c | 11 ----------- 1 file changed, 11 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 3603d5444865..e435223e2ddb 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5571,8 +5571,6 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, page = pfn_to_page(pfn); __init_single_page(page, pfn, zone, nid); - if (context == MEMMAP_HOTPLUG) - __SetPageReserved(page); /* * Mark the block movable so that blocks are reserved for @@ -5626,15 +5624,6 @@ void __ref memmap_init_zone_device(struct zone *zone, __init_single_page(page, pfn, zone_idx, nid); /* - * Mark page reserved as it will need to wait for onlining - * phase for it to be fully associated with a zone. - * - * We can use the non-atomic __set_bit operation for setting - * the flag as we are still initializing the pages. - */ - __SetPageReserved(page); - - /* * ZONE_DEVICE pages union ->lru with a ->pgmap back * pointer and hmm_data. It is a bug if a ZONE_DEVICE * page is ever freed or placed on a driver-private list.