From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx136.postini.com [74.125.245.136]) by kanga.kvack.org (Postfix) with SMTP id 8113C6B0073 for ; Thu, 22 Aug 2013 05:48:47 -0400 (EDT) Received: from /spool/local by e23smtp07.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 22 Aug 2013 19:35:14 +1000 Received: from d23relay05.au.ibm.com (d23relay05.au.ibm.com [9.190.235.152]) by d23dlp01.au.ibm.com (Postfix) with ESMTP id 327F92CE8057 for ; Thu, 22 Aug 2013 19:48:41 +1000 (EST) Received: from d23av04.au.ibm.com (d23av04.au.ibm.com [9.190.235.139]) by d23relay05.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r7M9WVMX66191424 for ; Thu, 22 Aug 2013 19:32:33 +1000 Received: from d23av04.au.ibm.com (loopback [127.0.0.1]) by d23av04.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id r7M9mcOP012739 for ; Thu, 22 Aug 2013 19:48:38 +1000 From: Wanpeng Li Subject: [PATCH 3/6] mm/hwpoison: fix num_poisoned_pages error statistics for thp Date: Thu, 22 Aug 2013 17:48:24 +0800 Message-Id: <1377164907-24801-3-git-send-email-liwanp@linux.vnet.ibm.com> In-Reply-To: <1377164907-24801-1-git-send-email-liwanp@linux.vnet.ibm.com> References: <1377164907-24801-1-git-send-email-liwanp@linux.vnet.ibm.com> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Andi Kleen , Fengguang Wu , Naoya Horiguchi , Tony Luck , gong.chen@linux.intel.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Wanpeng Li There is a race between hwpoison page and unpoison page, memory_failure set the page hwpoison and increase num_poisoned_pages without hold page lock, and one page count will be accounted against thp for num_poisoned_pages. However, unpoison can occur before memory_failure hold page lock and split transparent hugepage, unpoison will decrease num_poisoned_pages by 1 << compound_order since memory_failure has not yet split transparent hugepage with page lock held. That means we account one page for hwpoison and 1 << compound_order for unpoison. This patch fix it by decrease one account for num_poisoned_pages against no hugetlbfs pages case. Signed-off-by: Wanpeng Li --- mm/memory-failure.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 5092e06..6bfd51e 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1350,7 +1350,7 @@ int unpoison_memory(unsigned long pfn) return 0; } if (TestClearPageHWPoison(p)) - atomic_long_sub(nr_pages, &num_poisoned_pages); + atomic_long_dec(&num_poisoned_pages); pr_info("MCE: Software-unpoisoned free page %#lx\n", pfn); return 0; } -- 1.8.1.2 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org