Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755285Ab3HWKbJ (ORCPT ); Fri, 23 Aug 2013 06:31:09 -0400 Received: from e23smtp07.au.ibm.com ([202.81.31.140]:43047 "EHLO e23smtp07.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755063Ab3HWKbH (ORCPT ); Fri, 23 Aug 2013 06:31:07 -0400 From: Wanpeng Li 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 Subject: [PATCH v2 5/7] mm/hwpoison: don't set migration type twice to avoid hold heavy contend zone->lock Date: Fri, 23 Aug 2013 18:30:39 +0800 Message-Id: <1377253841-17620-5-git-send-email-liwanp@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1377253841-17620-1-git-send-email-liwanp@linux.vnet.ibm.com> References: <1377253841-17620-1-git-send-email-liwanp@linux.vnet.ibm.com> X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13082310-0260-0000-0000-00000382B4D5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1753 Lines: 42 v1 -> v2: * add more explanation in patch description. Set pageblock migration type will hold zone->lock which is heavy contended in system to avoid race. However, soft offline page will set pageblock migration type twice during get page if the page is in used, not hugetlbfs page and not on lru list. There is unnecessary to set the pageblock migration type and hold heavy contended zone->lock again if the first round get page have already set the pageblock to right migration type. The trick here is migration type is MIGRATE_ISOLATE. There are other two parts can change MIGRATE_ISOLATE except hwpoison. One is memory hoplug, however, we hold lock_memory_hotplug() which avoid race. The second is CMA which umovable page allocation requst can't fallback to. So it's safe here. Signed-off-by: Wanpeng Li --- mm/memory-failure.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 297965e..f357c91 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1426,7 +1426,8 @@ static int __get_any_page(struct page *p, unsigned long pfn, int flags) * was free. This flag should be kept set until the source page * is freed and PG_hwpoison on it is set. */ - set_migratetype_isolate(p, true); + if (get_pageblock_migratetype(p) == MIGRATE_ISOLATE) + set_migratetype_isolate(p, true); /* * When the target page is a free hugepage, just remove it * from free hugepage list. -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/