From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756436Ab3H3NV1 (ORCPT ); Fri, 30 Aug 2013 09:21:27 -0400 Received: from e7.ny.us.ibm.com ([32.97.182.137]:35353 "EHLO e7.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756405Ab3H3NVY (ORCPT ); Fri, 30 Aug 2013 09:21:24 -0400 From: "Srivatsa S. Bhat" Subject: [RFC PATCH v3 10/35] mm: Use the correct migratetype during buddy merging To: akpm@linux-foundation.org, mgorman@suse.de, hannes@cmpxchg.org, tony.luck@intel.com, matthew.garrett@nebula.com, dave@sr71.net, 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 Date: Fri, 30 Aug 2013 18:46:56 +0530 Message-ID: <20130830131654.4947.85409.stgit@srivatsabhat.in.ibm.com> In-Reply-To: <20130830131221.4947.99764.stgit@srivatsabhat.in.ibm.com> References: <20130830131221.4947.99764.stgit@srivatsabhat.in.ibm.com> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13083013-5806-0000-0000-000022964B7B Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: 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 b4b1275..07ac019 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -681,10 +681,14 @@ 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); From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Srivatsa S. Bhat" Subject: [RFC PATCH v3 10/35] mm: Use the correct migratetype during buddy merging Date: Fri, 30 Aug 2013 18:46:56 +0530 Message-ID: <20130830131654.4947.85409.stgit@srivatsabhat.in.ibm.com> References: <20130830131221.4947.99764.stgit@srivatsabhat.in.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20130830131221.4947.99764.stgit@srivatsabhat.in.ibm.com> Sender: owner-linux-mm@kvack.org To: akpm@linux-foundation.org, mgorman@suse.de, hannes@cmpxchg.org, tony.luck@intel.com, matthew.garrett@nebula.com, dave@sr71.net, 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 List-Id: linux-pm@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 b4b1275..07ac019 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -681,10 +681,14 @@ 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