From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f49.google.com (mail-pa0-f49.google.com [209.85.220.49]) by kanga.kvack.org (Postfix) with ESMTP id 335406B0031 for ; Wed, 25 Sep 2013 19:19:46 -0400 (EDT) Received: by mail-pa0-f49.google.com with SMTP id ld10so471313pab.22 for ; Wed, 25 Sep 2013 16:19:45 -0700 (PDT) Received: from /spool/local by e23smtp03.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 26 Sep 2013 09:19:41 +1000 Received: from d23relay03.au.ibm.com (d23relay03.au.ibm.com [9.190.235.21]) by d23dlp01.au.ibm.com (Postfix) with ESMTP id 8E3582CE8052 for ; Thu, 26 Sep 2013 09:19:39 +1000 (EST) Received: from d23av03.au.ibm.com (d23av03.au.ibm.com [9.190.234.97]) by d23relay03.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id r8PNJSU29503132 for ; Thu, 26 Sep 2013 09:19:28 +1000 Received: from d23av03.au.ibm.com (localhost [127.0.0.1]) by d23av03.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id r8PNJcw6013290 for ; Thu, 26 Sep 2013 09:19:39 +1000 From: "Srivatsa S. Bhat" Subject: [RFC PATCH v4 08/40] mm: Use the correct migratetype during buddy merging Date: Thu, 26 Sep 2013 04:45:28 +0530 Message-ID: <20130925231526.26184.60112.stgit@srivatsabhat.in.ibm.com> In-Reply-To: <20130925231250.26184.31438.stgit@srivatsabhat.in.ibm.com> References: <20130925231250.26184.31438.stgit@srivatsabhat.in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: akpm@linux-foundation.org, mgorman@suse.de, dave@sr71.net, hannes@cmpxchg.org, tony.luck@intel.com, matthew.garrett@nebula.com, riel@redhat.com, arjan@linux.intel.com, srinivas.pandruvada@linux.intel.com, willy@linux.intel.com, kamezawa.hiroyu@jp.fujitsu.com, lenb@kernel.org, rjw@sisk.pl Cc: gargankita@gmail.com, paulmck@linux.vnet.ibm.com, svaidy@linux.vnet.ibm.com, andi@firstfloor.org, isimatu.yasuaki@jp.fujitsu.com, santosh.shilimkar@ti.com, kosaki.motohiro@gmail.com, srivatsa.bhat@linux.vnet.ibm.com, linux-pm@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org While merging buddy free pages of a given order to make a higher order page, the buddy allocator might coalesce pages belonging to *two* *different* migratetypes of that order! So, don't assume that both the buddies come from the same freelist; instead, explicitly find out the migratetype info of the buddy page and use it while merging the buddies. Also, set the freepage migratetype of the buddy to the new one. Signed-off-by: Srivatsa S. Bhat --- mm/page_alloc.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index e31daf4..c40715c 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -685,10 +685,14 @@ static inline void __free_one_page(struct page *page, __mod_zone_freepage_state(zone, 1 << order, migratetype); } else { + int mt; + area = &zone->free_area[order]; - del_from_freelist(buddy, &area->free_list[migratetype]); + mt = get_freepage_migratetype(buddy); + del_from_freelist(buddy, &area->free_list[mt]); area->nr_free--; rmv_page_order(buddy); + set_freepage_migratetype(buddy, migratetype); } combined_idx = buddy_idx & page_idx; page = page + (combined_idx - page_idx); -- 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