Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936721Ab3DIVwE (ORCPT ); Tue, 9 Apr 2013 17:52:04 -0400 Received: from e28smtp07.in.ibm.com ([122.248.162.7]:45797 "EHLO e28smtp07.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S936705Ab3DIVv6 (ORCPT ); Tue, 9 Apr 2013 17:51:58 -0400 From: "Srivatsa S. Bhat" Subject: [RFC PATCH v2 13/15] mm: Implement the worker function for memory region compaction To: akpm@linux-foundation.org, mgorman@suse.de, matthew.garrett@nebula.com, dave@sr71.net, rientjes@google.com, riel@redhat.com, arjan@linux.intel.com, srinivas.pandruvada@linux.intel.com, maxime.coquelin@stericsson.com, loic.pallardy@stericsson.com, kamezawa.hiroyu@jp.fujitsu.com, lenb@kernel.org, rjw@sisk.pl Cc: gargankita@gmail.com, paulmck@linux.vnet.ibm.com, amit.kachhap@linaro.org, svaidy@linux.vnet.ibm.com, andi@firstfloor.org, wujianguo@huawei.com, kmpark@infradead.org, thomas.abraham@linaro.org, santosh.shilimkar@ti.com, srivatsa.bhat@linux.vnet.ibm.com, linux-pm@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Date: Wed, 10 Apr 2013 03:18:45 +0530 Message-ID: <20130409214843.4500.3852.stgit@srivatsabhat.in.ibm.com> In-Reply-To: <20130409214443.4500.44168.stgit@srivatsabhat.in.ibm.com> References: <20130409214443.4500.44168.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: 13040921-8878-0000-0000-000006A3C677 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4379 Lines: 150 We are going to invoke the memory compaction algorithms for region-evacuation from worker threads, instead of dedicating a separate kthread to it. So add the worker infrastructure to perform this. In the worker, we calculate the cost of migration/compaction for a given region - if we need to migrate less than 32 pages, then we go ahead, else we deem the effort to be too costly and abort the compaction. Signed-off-by: Srivatsa S. Bhat --- include/linux/mm.h | 20 ++++++++++++++++++++ include/linux/mmzone.h | 21 +++++++++++++++++++++ mm/page_alloc.c | 33 +++++++++++++++++++++++++++++++++ 3 files changed, 74 insertions(+) diff --git a/include/linux/mm.h b/include/linux/mm.h index cb0d898..e380eeb 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -755,6 +755,26 @@ static inline void set_next_region_in_freelist(struct free_list *free_list) } } +static inline int is_mem_pwr_work_in_progress(struct mem_power_ctrl *mpc) +{ + if (mpc->work_status == MEM_PWR_WORK_IN_PROGRESS) + return 1; + return 0; +} + +static inline void set_mem_pwr_work_in_progress(struct mem_power_ctrl *mpc) +{ + mpc->work_status = MEM_PWR_WORK_IN_PROGRESS; + smp_mb(); +} + +static inline void set_mem_pwr_work_complete(struct mem_power_ctrl *mpc) +{ + mpc->work_status = MEM_PWR_WORK_COMPLETE; + mpc->region = NULL; + smp_mb(); +} + #ifdef SECTION_IN_PAGE_FLAGS static inline void set_page_section(struct page *page, unsigned long section) { diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 6e209e9..fdadd2a 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -17,6 +17,7 @@ #include #include #include +#include #include /* Free memory management - zoned buddy allocator. */ @@ -337,6 +338,24 @@ enum zone_type { #ifndef __GENERATING_BOUNDS_H +/* + * In order to evacuate a memory region, if the no. of pages to be migrated + * via compaction is more than this number, the effort is considered too + * costly and should be aborted. + */ +#define MAX_NR_MEM_PWR_MIGRATE_PAGES 32 + +enum { + MEM_PWR_WORK_COMPLETE = 0, + MEM_PWR_WORK_IN_PROGRESS +}; + +struct mem_power_ctrl { + struct work_struct work; + struct zone_mem_region *region; + int work_status; +}; + struct zone_mem_region { unsigned long start_pfn; unsigned long end_pfn; @@ -405,6 +424,8 @@ struct zone { struct zone_mem_region zone_regions[MAX_NR_ZONE_REGIONS]; int nr_zone_regions; + struct mem_power_ctrl mem_power_ctrl; + #ifndef CONFIG_SPARSEMEM /* * Flags for a pageblock_nr_pages block. See pageblock-flags.h. diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 40a3aa6..db7b892 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5002,6 +5002,35 @@ static void __init_refok alloc_node_mem_map(struct pglist_data *pgdat) #endif /* CONFIG_FLAT_NODE_MEM_MAP */ } +static void mem_power_mgmt_fn(struct work_struct *work) +{ + struct mem_power_ctrl *mpc; + struct zone_mem_region *region; + unsigned long pages_in_use; + struct zone *zone; + + mpc = container_of(work, struct mem_power_ctrl, work); + + if (!mpc->region) + return; /* No work to do */ + + zone = container_of(mpc, struct zone, mem_power_ctrl); + region = mpc->region; + + if (region == zone->zone_regions) + return; /* No point compacting region 0. */ + + pages_in_use = region->present_pages - region->nr_free; + + if (pages_in_use > 0 && + (pages_in_use <= MAX_NR_MEM_PWR_MIGRATE_PAGES)) { + + evacuate_mem_region(zone, region); + } + + set_mem_pwr_work_complete(mpc); +} + static void __meminit init_node_memory_regions(struct pglist_data *pgdat) { int nid = pgdat->node_id; @@ -5094,6 +5123,10 @@ static void __meminit init_zone_memory_regions(struct pglist_data *pgdat) zone_init_free_lists_late(z); + INIT_WORK(&z->mem_power_ctrl.work, mem_power_mgmt_fn); + z->mem_power_ctrl.region = NULL; + set_mem_pwr_work_complete(&z->mem_power_ctrl); + /* * Revisit the last visited node memory region, in case it * spans multiple zones. -- 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/