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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 4DB13C433ED for ; Wed, 21 Apr 2021 02:13:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1ADEA6140D for ; Wed, 21 Apr 2021 02:13:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233894AbhDUCON (ORCPT ); Tue, 20 Apr 2021 22:14:13 -0400 Received: from mail-m121142.qiye.163.com ([115.236.121.142]:62476 "EHLO mail-m121142.qiye.163.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233824AbhDUCOJ (ORCPT ); Tue, 20 Apr 2021 22:14:09 -0400 X-Greylist: delayed 498 seconds by postgrey-1.27 at vger.kernel.org; Tue, 20 Apr 2021 22:14:09 EDT Received: from localhost.localdomain (unknown [14.154.30.246]) by mail-m121142.qiye.163.com (Hmail) with ESMTPA id 31595802E9; Wed, 21 Apr 2021 10:05:16 +0800 (CST) From: Ding Hui To: akpm@linux-foundation.org, naoya.horiguchi@nec.com, osalvador@suse.de Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Ding Hui Subject: [RFC PATCH] mm/page_alloc: fix counting of free pages after take off from buddy Date: Wed, 21 Apr 2021 10:04:26 +0800 Message-Id: <20210421020426.5914-1-dinghui@sangfor.com.cn> X-Mailer: git-send-email 2.17.1 X-HM-Spam-Status: e1kfGhgUHx5ZQUtXWQgYFAkeWUFZS1VLWVdZKFlBSE83V1ktWUFJV1kPCR oVCBIfWUFZGUhMHlZNH0NNTR8eS0tMH0pVEwETFhoSFyQUDg9ZV1kWGg8SFR0UWUFZT0tIVUpKS0 9ISFVLWQY+ X-HM-Sender-Digest: e1kMHhlZQR0aFwgeV1kSHx4VD1lBWUc6NBQ6Izo4UT8TEgkINjFCKQ4i GSkwCUlVSlVKTUpDQkxLTEpNTENOVTMWGhIXVR8SFRwTDhI7CBoVHB0UCVUYFBZVGBVFWVdZEgtZ QVlKT1VKTk9VSEtVSU9NWVdZCAFZQUpMSU43Bg++ X-HM-Tid: 0a78f22ca8e4b037kuuu31595802e9 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Recently we found there is a lot MemFree left in /proc/meminfo after do a lot of pages soft offline. I think it's incorrect since NR_FREE_PAGES should not contain HWPoison pages. After take_page_off_buddy, the page is no longer belong to buddy allocator, and will not be used any more, but we maybe missed accounting NR_FREE_PAGES in this situation. Signed-off-by: Ding Hui --- mm/page_alloc.c | 1 + 1 file changed, 1 insertion(+) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index cfc72873961d..8d65b62784d8 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -8947,6 +8947,7 @@ bool take_page_off_buddy(struct page *page) del_page_from_free_list(page_head, zone, page_order); break_down_buddy_pages(zone, page_head, page, 0, page_order, migratetype); + __mod_zone_page_state(zone, NR_FREE_PAGES, -1); ret = true; break; } -- 2.17.1