Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751549Ab0KSISV (ORCPT ); Fri, 19 Nov 2010 03:18:21 -0500 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:48154 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751061Ab0KSISU (ORCPT ); Fri, 19 Nov 2010 03:18:20 -0500 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 Date: Fri, 19 Nov 2010 17:12:39 +0900 From: KAMEZAWA Hiroyuki To: KAMEZAWA Hiroyuki Cc: "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , minchan.kim@gmail.com, Bob Liu , fujita.tomonori@lab.ntt.co.jp, m.nazarewicz@samsung.com, pawel@osciak.com, andi.kleen@intel.com, felipe.contreras@gmail.com, "akpm@linux-foundation.org" , "kosaki.motohiro@jp.fujitsu.com" Subject: [PATCH 1/4] alloc_contig_pages() move some functions to page_isolation.c Message-Id: <20101119171239.7f544c7c.kamezawa.hiroyu@jp.fujitsu.com> In-Reply-To: <20101119171033.a8d9dc8f.kamezawa.hiroyu@jp.fujitsu.com> References: <20101119171033.a8d9dc8f.kamezawa.hiroyu@jp.fujitsu.com> Organization: FUJITSU Co. LTD. X-Mailer: Sylpheed 3.0.3 (GTK+ 2.10.14; i686-pc-mingw32) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7791 Lines: 290 From: KAMEZAWA Hiroyuki Memory hotplug is a logic for making pages unused in the specified range of pfn. So, some of core logics can be used for other purpose as allocating a very large contigous memory block. This patch moves some functions from mm/memory_hotplug.c to mm/page_isolation.c. This helps adding a function for large-alloc in page_isolation.c with memory-unplug technique. Changelog: 2010/10/26 - adjusted to mmotm-1024 + Bob's 3 clean ups. Changelog: 2010/10/21 - adjusted to mmotm-1020 Signed-off-by: KAMEZAWA Hiroyuki --- include/linux/page-isolation.h | 7 ++ mm/memory_hotplug.c | 108 --------------------------------------- mm/page_isolation.c | 111 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 118 insertions(+), 108 deletions(-) Index: mmotm-1117/include/linux/page-isolation.h =================================================================== --- mmotm-1117.orig/include/linux/page-isolation.h +++ mmotm-1117/include/linux/page-isolation.h @@ -33,5 +33,12 @@ test_pages_isolated(unsigned long start_ extern int set_migratetype_isolate(struct page *page); extern void unset_migratetype_isolate(struct page *page); +/* + * For migration. + */ + +int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn); +unsigned long scan_lru_pages(unsigned long start, unsigned long end); +int do_migrate_range(unsigned long start_pfn, unsigned long end_pfn); #endif Index: mmotm-1117/mm/memory_hotplug.c =================================================================== --- mmotm-1117.orig/mm/memory_hotplug.c +++ mmotm-1117/mm/memory_hotplug.c @@ -615,114 +615,6 @@ int is_mem_section_removable(unsigned lo } /* - * Confirm all pages in a range [start, end) is belongs to the same zone. - */ -static int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn) -{ - unsigned long pfn; - struct zone *zone = NULL; - struct page *page; - int i; - for (pfn = start_pfn; - pfn < end_pfn; - pfn += MAX_ORDER_NR_PAGES) { - i = 0; - /* This is just a CONFIG_HOLES_IN_ZONE check.*/ - while ((i < MAX_ORDER_NR_PAGES) && !pfn_valid_within(pfn + i)) - i++; - if (i == MAX_ORDER_NR_PAGES) - continue; - page = pfn_to_page(pfn + i); - if (zone && page_zone(page) != zone) - return 0; - zone = page_zone(page); - } - return 1; -} - -/* - * Scanning pfn is much easier than scanning lru list. - * Scan pfn from start to end and Find LRU page. - */ -static unsigned long scan_lru_pages(unsigned long start, unsigned long end) -{ - unsigned long pfn; - struct page *page; - for (pfn = start; pfn < end; pfn++) { - if (pfn_valid(pfn)) { - page = pfn_to_page(pfn); - if (PageLRU(page)) - return pfn; - } - } - return 0; -} - -static struct page * -hotremove_migrate_alloc(struct page *page, unsigned long private, int **x) -{ - /* This should be improooooved!! */ - return alloc_page(GFP_HIGHUSER_MOVABLE); -} - -#define NR_OFFLINE_AT_ONCE_PAGES (256) -static int -do_migrate_range(unsigned long start_pfn, unsigned long end_pfn) -{ - unsigned long pfn; - struct page *page; - int move_pages = NR_OFFLINE_AT_ONCE_PAGES; - int not_managed = 0; - int ret = 0; - LIST_HEAD(source); - - for (pfn = start_pfn; pfn < end_pfn && move_pages > 0; pfn++) { - if (!pfn_valid(pfn)) - continue; - page = pfn_to_page(pfn); - if (!page_count(page)) - continue; - /* - * We can skip free pages. And we can only deal with pages on - * LRU. - */ - ret = isolate_lru_page(page); - if (!ret) { /* Success */ - list_add_tail(&page->lru, &source); - move_pages--; - inc_zone_page_state(page, NR_ISOLATED_ANON + - page_is_file_cache(page)); - - } else { -#ifdef CONFIG_DEBUG_VM - printk(KERN_ALERT "removing pfn %lx from LRU failed\n", - pfn); - dump_page(page); -#endif - /* Becasue we don't have big zone->lock. we should - check this again here. */ - if (page_count(page)) { - not_managed++; - ret = -EBUSY; - break; - } - } - } - if (!list_empty(&source)) { - if (not_managed) { - putback_lru_pages(&source); - goto out; - } - /* this function returns # of failed pages */ - ret = migrate_pages(&source, hotremove_migrate_alloc, 0, 1); - if (ret) - putback_lru_pages(&source); - } -out: - return ret; -} - -/* * remove from free_area[] and mark all as Reserved. */ static int Index: mmotm-1117/mm/page_isolation.c =================================================================== --- mmotm-1117.orig/mm/page_isolation.c +++ mmotm-1117/mm/page_isolation.c @@ -5,6 +5,9 @@ #include #include #include +#include +#include +#include #include "internal.h" static inline struct page * @@ -139,3 +142,111 @@ int test_pages_isolated(unsigned long st spin_unlock_irqrestore(&zone->lock, flags); return ret ? 0 : -EBUSY; } + + +/* + * Confirm all pages in a range [start, end) is belongs to the same zone. + */ +int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn) +{ + unsigned long pfn; + struct zone *zone = NULL; + struct page *page; + int i; + for (pfn = start_pfn; + pfn < end_pfn; + pfn += MAX_ORDER_NR_PAGES) { + i = 0; + /* This is just a CONFIG_HOLES_IN_ZONE check.*/ + while ((i < MAX_ORDER_NR_PAGES) && !pfn_valid_within(pfn + i)) + i++; + if (i == MAX_ORDER_NR_PAGES) + continue; + page = pfn_to_page(pfn + i); + if (zone && page_zone(page) != zone) + return 0; + zone = page_zone(page); + } + return 1; +} + +/* + * Scanning pfn is much easier than scanning lru list. + * Scan pfn from start to end and Find LRU page. + */ +unsigned long scan_lru_pages(unsigned long start, unsigned long end) +{ + unsigned long pfn; + struct page *page; + for (pfn = start; pfn < end; pfn++) { + if (pfn_valid(pfn)) { + page = pfn_to_page(pfn); + if (PageLRU(page)) + return pfn; + } + } + return 0; +} + +struct page * +hotremove_migrate_alloc(struct page *page, unsigned long private, int **x) +{ + /* This should be improooooved!! */ + return alloc_page(GFP_HIGHUSER_MOVABLE); +} + +#define NR_OFFLINE_AT_ONCE_PAGES (256) +int do_migrate_range(unsigned long start_pfn, unsigned long end_pfn) +{ + unsigned long pfn; + struct page *page; + int move_pages = NR_OFFLINE_AT_ONCE_PAGES; + int not_managed = 0; + int ret = 0; + LIST_HEAD(source); + + for (pfn = start_pfn; pfn < end_pfn && move_pages > 0; pfn++) { + if (!pfn_valid(pfn)) + continue; + page = pfn_to_page(pfn); + if (!page_count(page)) + continue; + /* + * We can skip free pages. And we can only deal with pages on + * LRU. + */ + ret = isolate_lru_page(page); + if (!ret) { /* Success */ + list_add_tail(&page->lru, &source); + move_pages--; + inc_zone_page_state(page, NR_ISOLATED_ANON + + page_is_file_cache(page)); + + } else { +#ifdef CONFIG_DEBUG_VM + printk(KERN_ALERT "removing pfn %lx from LRU failed\n", + pfn); + dump_page(page); +#endif + /* Because we don't have big zone->lock. we should + check this again here. */ + if (page_count(page)) { + not_managed++; + ret = -EBUSY; + break; + } + } + } + if (!list_empty(&source)) { + if (not_managed) { + putback_lru_pages(&source); + goto out; + } + /* this function returns # of failed pages */ + ret = migrate_pages(&source, hotremove_migrate_alloc, 0, 1); + if (ret) + putback_lru_pages(&source); + } +out: + return ret; +} -- 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/