From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754310Ab3I0Nef (ORCPT ); Fri, 27 Sep 2013 09:34:35 -0400 Received: from cantor2.suse.de ([195.135.220.15]:55855 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753880Ab3I0N2f (ORCPT ); Fri, 27 Sep 2013 09:28:35 -0400 From: Mel Gorman To: Peter Zijlstra , Rik van Riel Cc: Srikar Dronamraju , Ingo Molnar , Andrea Arcangeli , Johannes Weiner , Linux-MM , LKML , Mel Gorman Subject: [PATCH 45/63] mm: numa: copy cpupid on page migration Date: Fri, 27 Sep 2013 14:27:30 +0100 Message-Id: <1380288468-5551-46-git-send-email-mgorman@suse.de> X-Mailer: git-send-email 1.8.1.4 In-Reply-To: <1380288468-5551-1-git-send-email-mgorman@suse.de> References: <1380288468-5551-1-git-send-email-mgorman@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rik van Riel After page migration, the new page has the nidpid unset. This makes every fault on a recently migrated page look like a first numa fault, leading to another page migration. Copying over the nidpid at page migration time should prevent erroneous migrations of recently migrated pages. Signed-off-by: Rik van Riel Signed-off-by: Mel Gorman --- mm/migrate.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/mm/migrate.c b/mm/migrate.c index 6ff845f..1e1dbc9 100644 --- a/mm/migrate.c +++ b/mm/migrate.c @@ -439,6 +439,8 @@ int migrate_huge_page_move_mapping(struct address_space *mapping, */ void migrate_page_copy(struct page *newpage, struct page *page) { + int cpupid; + if (PageHuge(page) || PageTransHuge(page)) copy_huge_page(newpage, page); else @@ -475,6 +477,13 @@ void migrate_page_copy(struct page *newpage, struct page *page) __set_page_dirty_nobuffers(newpage); } + /* + * Copy NUMA information to the new page, to prevent over-eager + * future migrations of this same page. + */ + cpupid = page_cpupid_xchg_last(page, -1); + page_cpupid_xchg_last(newpage, cpupid); + mlock_migrate_page(newpage, page); ksm_migrate_page(newpage, page); /* -- 1.8.1.4