Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756235Ab3IYXYd (ORCPT ); Wed, 25 Sep 2013 19:24:33 -0400 Received: from e28smtp08.in.ibm.com ([122.248.162.8]:42287 "EHLO e28smtp08.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755343Ab3IYXY3 (ORCPT ); Wed, 25 Sep 2013 19:24:29 -0400 From: "Srivatsa S. Bhat" Subject: [RFC PATCH v4 29/40] mm: Add a way to request pages of a particular region from the region allocator 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 Date: Thu, 26 Sep 2013 04:50:15 +0530 Message-ID: <20130925232014.26184.62048.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> 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: 13092523-2000-0000-0000-00000DDDF120 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3445 Lines: 97 When moving freepages from one migratetype to another (using move_freepages() or equivalent), we might encounter situations in which we would like to move pages that are in the region allocator. In such cases, we need a way to request pages of a particular region from the region allocator. We already have the code to perform the heavy-lifting of actually moving the pages of a region from the region allocator to a requested freelist or migratetype. So just reorganize that code in such a way that we can also pin-point a region and specify that we want the region allocator to allocate pages from that particular region. Signed-off-by: Srivatsa S. Bhat --- mm/page_alloc.c | 40 ++++++++++++++++++++++++---------------- 1 file changed, 24 insertions(+), 16 deletions(-) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index ac04b45..ed5298c 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1003,24 +1003,18 @@ static void add_to_region_allocator(struct zone *z, struct free_list *free_list, *next_region = region_id; } -/* Delete freepages from the region allocator and add them to buddy freelists */ -static int del_from_region_allocator(struct zone *zone, unsigned int order, - int migratetype) +static void __del_from_region_allocator(struct zone *zone, unsigned int order, + int migratetype, int region_id) { struct region_allocator *reg_alloc; struct free_area_region *reg_area; struct list_head *ralloc_list; struct free_list *free_list; unsigned long nr_pages; - int next_region; + struct page *page; reg_alloc = &zone->region_allocator; - - next_region = reg_alloc->next_region; - if (next_region < 0) - return -ENOMEM; - - reg_area = ®_alloc->region[next_region].region_area[order]; + reg_area = ®_alloc->region[region_id].region_area[order]; ralloc_list = ®_area->list; list_for_each_entry(page, ralloc_list, lru) @@ -1029,20 +1023,34 @@ static int del_from_region_allocator(struct zone *zone, unsigned int order, free_list = &zone->free_area[order].free_list[migratetype]; nr_pages = add_to_freelist_bulk(ralloc_list, free_list, order, - next_region); + region_id); reg_area->nr_free -= nr_pages; WARN_ON(reg_area->nr_free != 0); /* Pick a new next_region */ - clear_bit(next_region, reg_alloc->ralloc_mask); - next_region = find_first_bit(reg_alloc->ralloc_mask, + clear_bit(region_id, reg_alloc->ralloc_mask); + region_id = find_first_bit(reg_alloc->ralloc_mask, MAX_NR_ZONE_REGIONS); - if (next_region >= MAX_NR_ZONE_REGIONS) - next_region = -1; /* No free regions available */ + if (region_id >= MAX_NR_ZONE_REGIONS) + region_id = -1; /* No free regions available */ + + reg_alloc->next_region = region_id; +} + +/* Delete freepages from the region allocator and add them to buddy freelists */ +static int del_from_region_allocator(struct zone *zone, unsigned int order, + int migratetype) +{ + int next_region; + + next_region = zone->region_allocator.next_region; + + if (next_region < 0) + return -ENOMEM; - reg_alloc->next_region = next_region; + __del_from_region_allocator(zone, order, migratetype, next_region); return 0; } -- 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/