Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932207AbVJ3SfG (ORCPT ); Sun, 30 Oct 2005 13:35:06 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932206AbVJ3Sek (ORCPT ); Sun, 30 Oct 2005 13:34:40 -0500 Received: from holly.csn.ul.ie ([136.201.105.4]:43947 "EHLO holly.csn.ul.ie") by vger.kernel.org with ESMTP id S932207AbVJ3SeL (ORCPT ); Sun, 30 Oct 2005 13:34:11 -0500 From: Mel Gorman To: akpm@osdl.org Cc: linux-mm@kvack.org, lhms-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, Mel Gorman Message-Id: <20051030183409.22266.50049.sendpatchset@skynet.csn.ul.ie> In-Reply-To: <20051030183354.22266.42795.sendpatchset@skynet.csn.ul.ie> References: <20051030183354.22266.42795.sendpatchset@skynet.csn.ul.ie> Subject: [PATCH 3/7] Fragmentation Avoidance V19: 003_fragcore Date: Sun, 30 Oct 2005 18:34:10 +0000 (GMT) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10800 Lines: 349 This patch adds the core of the anti-fragmentation strategy. It works by grouping related allocation types together. The idea is that large groups of pages that may be reclaimed are placed near each other. The zone->free_area list is broken into three free lists for each RCLM_TYPE. This section of the patch looks superflous but it is to surpress a compiler warning. Suggestions to make this better looking are welcome. - struct free_area * area; + struct free_area * area = NULL; Signed-off-by: Mel Gorman Signed-off-by: Mike Kravetz Signed-off-by: Joel Schopp diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-002_usemap/include/linux/mmzone.h linux-2.6.14-rc5-mm1-003_fragcore/include/linux/mmzone.h --- linux-2.6.14-rc5-mm1-002_usemap/include/linux/mmzone.h 2005-10-30 13:35:31.000000000 +0000 +++ linux-2.6.14-rc5-mm1-003_fragcore/include/linux/mmzone.h 2005-10-30 13:36:16.000000000 +0000 @@ -33,6 +33,10 @@ #define RCLM_TYPES 3 #define BITS_PER_RCLM_TYPE 2 +#define for_each_rclmtype_order(type, order) \ + for (order = 0; order < MAX_ORDER; order++) \ + for (type = 0; type < RCLM_TYPES; type++) + struct free_area { struct list_head free_list; unsigned long nr_free; @@ -155,7 +159,6 @@ struct zone { /* see spanned/present_pages for more description */ seqlock_t span_seqlock; #endif - struct free_area free_area[MAX_ORDER]; #ifndef CONFIG_SPARSEMEM /* @@ -165,6 +168,8 @@ struct zone { unsigned long *free_area_usemap; #endif + struct free_area free_area_lists[RCLM_TYPES][MAX_ORDER]; + ZONE_PADDING(_pad1_) /* Fields commonly accessed by the page reclaim scanner */ diff -rup -X /usr/src/patchset-0.5/bin//dontdiff linux-2.6.14-rc5-mm1-002_usemap/mm/page_alloc.c linux-2.6.14-rc5-mm1-003_fragcore/mm/page_alloc.c --- linux-2.6.14-rc5-mm1-002_usemap/mm/page_alloc.c 2005-10-30 13:35:31.000000000 +0000 +++ linux-2.6.14-rc5-mm1-003_fragcore/mm/page_alloc.c 2005-10-30 13:36:16.000000000 +0000 @@ -352,6 +352,15 @@ __find_combined_index(unsigned long page } /* + * Return the free list for a given page within a zone + */ +static inline struct free_area *__page_find_freelist(struct zone *zone, + struct page *page) +{ + return zone->free_area_lists[get_pageblock_type(zone, page)]; +} + +/* * This function checks whether a page is free && is the buddy * we can do coalesce a page and its buddy if * (a) the buddy is free && @@ -398,6 +407,8 @@ static inline void __free_pages_bulk (st { unsigned long page_idx; int order_size = 1 << order; + struct free_area *area; + struct free_area *freelist; if (unlikely(order)) destroy_compound_page(page, order); @@ -407,10 +418,11 @@ static inline void __free_pages_bulk (st BUG_ON(page_idx & (order_size - 1)); BUG_ON(bad_range(zone, page)); + freelist = __page_find_freelist(zone, page); + zone->free_pages += order_size; while (order < MAX_ORDER-1) { unsigned long combined_idx; - struct free_area *area; struct page *buddy; combined_idx = __find_combined_index(page_idx, order); @@ -421,7 +433,7 @@ static inline void __free_pages_bulk (st if (!page_is_buddy(buddy, order)) break; /* Move the buddy up one level. */ list_del(&buddy->lru); - area = zone->free_area + order; + area = &freelist[order]; area->nr_free--; rmv_page_order(buddy); page = page + (combined_idx - page_idx); @@ -429,8 +441,8 @@ static inline void __free_pages_bulk (st order++; } set_page_order(page, order); - list_add(&page->lru, &zone->free_area[order].free_list); - zone->free_area[order].nr_free++; + list_add_tail(&page->lru, &freelist[order].free_list); + freelist[order].nr_free++; } static inline void free_pages_check(const char *function, struct page *page) @@ -587,6 +599,45 @@ static void prep_new_page(struct page *p kernel_map_pages(page, 1 << order, 1); } +/* + * Find a list that has a 2^MAX_ORDER-1 block of pages available and + * return it + */ +struct page *steal_maxorder_block(struct zone *zone, int alloctype) +{ + struct page *page; + struct free_area *area = NULL; + int i; + + for(i = 0; i < RCLM_TYPES; i++) { + if (i == alloctype) + continue; + + area = &zone->free_area_lists[i][MAX_ORDER-1]; + if (!list_empty(&area->free_list)) + break; + } + if (i == RCLM_TYPES) + return NULL; + + page = list_entry(area->free_list.next, struct page, lru); + area->nr_free--; + + set_pageblock_type(zone, page, alloctype); + + return page; +} + +static inline struct page * +remove_page(struct zone *zone, struct page *page, unsigned int order, + unsigned int current_order, struct free_area *area) +{ + list_del(&page->lru); + rmv_page_order(page); + zone->free_pages -= 1UL << order; + return expand(zone, page, order, current_order, area); +} + /* * Do the hard work of removing an element from the buddy allocator. * Call me with the zone->lock already held. @@ -594,31 +645,25 @@ static void prep_new_page(struct page *p static struct page *__rmqueue(struct zone *zone, unsigned int order, int alloctype) { - struct free_area * area; + struct free_area * area = NULL; unsigned int current_order; struct page *page; for (current_order = order; current_order < MAX_ORDER; ++current_order) { - area = zone->free_area + current_order; + area = &zone->free_area_lists[alloctype][current_order]; if (list_empty(&area->free_list)) continue; page = list_entry(area->free_list.next, struct page, lru); - list_del(&page->lru); - rmv_page_order(page); area->nr_free--; - zone->free_pages -= 1UL << order; - - /* - * If splitting a large block, record what the block is being - * used for in the usemap - */ - if (current_order == MAX_ORDER-1) - set_pageblock_type(zone, page, alloctype); - - return expand(zone, page, order, current_order, area); + return remove_page(zone, page, order, current_order, area); } + /* Allocate a MAX_ORDER block */ + page = steal_maxorder_block(zone, alloctype); + if (page != NULL) + return remove_page(zone, page, order, MAX_ORDER-1, area); + return NULL; } @@ -704,9 +749,9 @@ static void __drain_pages(unsigned int c void mark_free_pages(struct zone *zone) { unsigned long zone_pfn, flags; - int order; + int order, t; + unsigned long start_pfn, i; struct list_head *curr; - if (!zone->spanned_pages) return; @@ -714,14 +759,12 @@ void mark_free_pages(struct zone *zone) for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) ClearPageNosaveFree(pfn_to_page(zone_pfn + zone->zone_start_pfn)); - for (order = MAX_ORDER - 1; order >= 0; --order) - list_for_each(curr, &zone->free_area[order].free_list) { - unsigned long start_pfn, i; - + for_each_rclmtype_order(t, order) { + list_for_each(curr,&zone->free_area_lists[t][order].free_list) { start_pfn = page_to_pfn(list_entry(curr, struct page, lru)); - for (i=0; i < (1<lock, flags); } @@ -876,6 +919,7 @@ int zone_watermark_ok(struct zone *z, in /* free_pages my go negative - that's OK */ long min = mark, free_pages = z->free_pages - (1 << order) + 1; int o; + struct free_area *kernnorclm, *kernrclm, *easyrclm; if (gfp_high) min -= min / 2; @@ -884,15 +928,22 @@ int zone_watermark_ok(struct zone *z, in if (free_pages <= min + z->lowmem_reserve[classzone_idx]) goto out_failed; + kernnorclm = z->free_area_lists[RCLM_NORCLM]; + easyrclm = z->free_area_lists[RCLM_EASY]; + kernrclm = z->free_area_lists[RCLM_KERN]; for (o = 0; o < order; o++) { /* At the next order, this order's pages become unavailable */ - free_pages -= z->free_area[o].nr_free << o; + free_pages -= (kernnorclm->nr_free + kernrclm->nr_free + + easyrclm->nr_free) << o; /* Require fewer higher order pages to be free */ min >>= 1; if (free_pages <= min) goto out_failed; + kernnorclm++; + easyrclm++; + kernrclm++; } return 1; @@ -1496,6 +1547,7 @@ void show_free_areas(void) unsigned long inactive; unsigned long free; struct zone *zone; + int type; for_each_zone(zone) { show_node(zone); @@ -1575,7 +1627,9 @@ void show_free_areas(void) } for_each_zone(zone) { - unsigned long nr, flags, order, total = 0; + unsigned long nr = 0; + unsigned long total = 0; + unsigned long flags,order; show_node(zone); printk("%s: ", zone->name); @@ -1585,10 +1639,18 @@ void show_free_areas(void) } spin_lock_irqsave(&zone->lock, flags); - for (order = 0; order < MAX_ORDER; order++) { - nr = zone->free_area[order].nr_free; + for_each_rclmtype_order(type, order) { + nr += zone->free_area_lists[type][order].nr_free; total += nr << order; - printk("%lu*%lukB ", nr, K(1UL) << order); + + /* + * If type had reached RCLM_TYPE, the free pages + * for this order have been summed up + */ + if (type == RCLM_TYPES-1) { + printk("%lu*%lukB ", nr, K(1UL) << order); + nr = 0; + } } spin_unlock_irqrestore(&zone->lock, flags); printk("= %lukB\n", K(total)); @@ -1899,9 +1961,14 @@ void zone_init_free_lists(struct pglist_ unsigned long size) { int order; - for (order = 0; order < MAX_ORDER ; order++) { - INIT_LIST_HEAD(&zone->free_area[order].free_list); - zone->free_area[order].nr_free = 0; + int type; + struct free_area *area; + + /* Initialse the three size ordered lists of free_areas */ + for_each_rclmtype_order(type, order) { + area = &(zone->free_area_lists[type][order]); + INIT_LIST_HEAD(&area->free_list); + area->nr_free = 0; } } @@ -2314,16 +2381,26 @@ static int frag_show(struct seq_file *m, struct zone *zone; struct zone *node_zones = pgdat->node_zones; unsigned long flags; - int order; + int order, t; + struct free_area *area; + unsigned long nr_bufs = 0; for (zone = node_zones; zone - node_zones < MAX_NR_ZONES; ++zone) { if (!zone->present_pages) continue; spin_lock_irqsave(&zone->lock, flags); - seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name); - for (order = 0; order < MAX_ORDER; ++order) - seq_printf(m, "%6lu ", zone->free_area[order].nr_free); + seq_printf(m, "Node %d, zone %8s", pgdat->node_id, zone->name); + for_each_rclmtype_order(t, order) { + area = &(zone->free_area_lists[t][order]); + nr_bufs += area->nr_free; + + if (t == RCLM_TYPES-1) { + seq_printf(m, "%6lu ", nr_bufs); + nr_bufs = 0; + } + } + spin_unlock_irqrestore(&zone->lock, flags); seq_putc(m, '\n'); } - 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/