From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with ESMTP id 069526B005A for ; Tue, 18 Aug 2009 07:16:03 -0400 (EDT) From: Mel Gorman Subject: [PATCH 3/3] page-allocator: Move pcp static fields for high and batch off-pcp and onto the zone Date: Tue, 18 Aug 2009 12:16:02 +0100 Message-Id: <1250594162-17322-4-git-send-email-mel@csn.ul.ie> In-Reply-To: <1250594162-17322-1-git-send-email-mel@csn.ul.ie> References: <1250594162-17322-1-git-send-email-mel@csn.ul.ie> Sender: owner-linux-mm@kvack.org To: Linux Memory Management List Cc: Christoph Lameter , Nick Piggin , Linux Kernel Mailing List , Mel Gorman List-ID: Having multiple lists per PCPU increased the size of the per-pcpu structure. Two of the fields, high and batch, do not change within a zone making that information redundant. This patch moves those fields off the PCP and onto the zone to reduce the size of the PCPU. Signed-off-by: Mel Gorman --- include/linux/mmzone.h | 9 +++++---- mm/page_alloc.c | 47 +++++++++++++++++++++++++---------------------- mm/vmstat.c | 4 ++-- 3 files changed, 32 insertions(+), 28 deletions(-) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 6e0b624..57a3ef0 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -167,12 +167,10 @@ enum zone_watermarks { #define high_wmark_pages(z) (z->watermark[WMARK_HIGH]) struct per_cpu_pages { - int count; /* number of pages in the list */ - int high; /* high watermark, emptying needed */ - int batch; /* chunk size for buddy add/remove */ - /* Lists of pages, one per migrate type stored on the pcp-lists */ struct list_head lists[MIGRATE_PCPTYPES]; + + int count; /* number of pages in the list */ }; struct per_cpu_pageset { @@ -284,6 +282,9 @@ struct zone { /* zone watermarks, access with *_wmark_pages(zone) macros */ unsigned long watermark[NR_WMARK]; + int pcp_high; /* high watermark, emptying needed */ + int pcp_batch; /* chunk size for buddy add/remove */ + /* * We don't know if the memory that we're going to allocate will be freeable * or/and it will be released eventually, so to avoid totally wasting several diff --git a/mm/page_alloc.c b/mm/page_alloc.c index dd3f306..65cdfbf 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -988,8 +988,8 @@ void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp) int to_drain; local_irq_save(flags); - if (pcp->count >= pcp->batch) - to_drain = pcp->batch; + if (pcp->count >= zone->pcp_batch) + to_drain = zone->pcp_batch; else to_drain = pcp->count; free_pcppages_bulk(zone, to_drain, pcp); @@ -1129,9 +1129,9 @@ static void free_hot_cold_page(struct page *page, int cold) else list_add(&page->lru, &pcp->lists[migratetype]); pcp->count++; - if (pcp->count >= pcp->high) { - free_pcppages_bulk(zone, pcp->batch, pcp); - pcp->count -= pcp->batch; + if (pcp->count >= zone->pcp_high) { + free_pcppages_bulk(zone, zone->pcp_batch, pcp); + pcp->count -= zone->pcp_batch; } out: @@ -1199,7 +1199,7 @@ again: local_irq_save(flags); if (list_empty(list)) { pcp->count += rmqueue_bulk(zone, 0, - pcp->batch, list, + zone->pcp_batch, list, migratetype, cold); if (unlikely(list_empty(list))) goto failed; @@ -2178,8 +2178,8 @@ void show_free_areas(void) pageset = zone_pcp(zone, cpu); printk("CPU %4d: hi:%5d, btch:%4d usd:%4d\n", - cpu, pageset->pcp.high, - pageset->pcp.batch, pageset->pcp.count); + cpu, zone->pcp_high, + zone->pcp_batch, pageset->pcp.count); } } @@ -3045,7 +3045,9 @@ static int zone_batchsize(struct zone *zone) #endif } -static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch) +static void setup_pageset(struct zone *zone, + struct per_cpu_pageset *p, + unsigned long batch) { struct per_cpu_pages *pcp; int migratetype; @@ -3054,8 +3056,8 @@ static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch) pcp = &p->pcp; pcp->count = 0; - pcp->high = 6 * batch; - pcp->batch = max(1UL, 1 * batch); + zone->pcp_high = 6 * batch; + zone->pcp_batch = max(1UL, 1 * batch); for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++) INIT_LIST_HEAD(&pcp->lists[migratetype]); } @@ -3065,16 +3067,17 @@ static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch) * to the value high for the pageset p. */ -static void setup_pagelist_highmark(struct per_cpu_pageset *p, +static void setup_pagelist_highmark(struct zone *zone, + struct per_cpu_pageset *p, unsigned long high) { struct per_cpu_pages *pcp; pcp = &p->pcp; - pcp->high = high; - pcp->batch = max(1UL, high/4); + zone->pcp_high = high; + zone->pcp_batch = max(1UL, high/4); if ((high/4) > (PAGE_SHIFT * 8)) - pcp->batch = PAGE_SHIFT * 8; + zone->pcp_batch = PAGE_SHIFT * 8; } @@ -3115,10 +3118,10 @@ static int __cpuinit process_zones(int cpu) if (!zone_pcp(zone, cpu)) goto bad; - setup_pageset(zone_pcp(zone, cpu), zone_batchsize(zone)); + setup_pageset(zone, zone_pcp(zone, cpu), zone_batchsize(zone)); if (percpu_pagelist_fraction) - setup_pagelist_highmark(zone_pcp(zone, cpu), + setup_pagelist_highmark(zone, zone_pcp(zone, cpu), (zone->present_pages / percpu_pagelist_fraction)); } @@ -3250,7 +3253,7 @@ static int __zone_pcp_update(void *data) local_irq_save(flags); free_pcppages_bulk(zone, pcp->count, pcp); - setup_pageset(pset, batch); + setup_pageset(zone, pset, batch); local_irq_restore(flags); } return 0; @@ -3270,9 +3273,9 @@ static __meminit void zone_pcp_init(struct zone *zone) #ifdef CONFIG_NUMA /* Early boot. Slab allocator not functional yet */ zone_pcp(zone, cpu) = &boot_pageset[cpu]; - setup_pageset(&boot_pageset[cpu],0); + setup_pageset(zone, &boot_pageset[cpu],0); #else - setup_pageset(zone_pcp(zone,cpu), batch); + setup_pageset(zone, zone_pcp(zone,cpu), batch); #endif } if (zone->present_pages) @@ -4781,7 +4784,7 @@ int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write, } /* - * percpu_pagelist_fraction - changes the pcp->high for each zone on each + * percpu_pagelist_fraction - changes the zone->pcp_high for each zone on each * cpu. It is the fraction of total pages in each zone that a hot per cpu pagelist * can have before it gets flushed back to buddy allocator. */ @@ -4800,7 +4803,7 @@ int percpu_pagelist_fraction_sysctl_handler(ctl_table *table, int write, for_each_online_cpu(cpu) { unsigned long high; high = zone->present_pages / percpu_pagelist_fraction; - setup_pagelist_highmark(zone_pcp(zone, cpu), high); + setup_pagelist_highmark(zone, zone_pcp(zone, cpu), high); } } return 0; diff --git a/mm/vmstat.c b/mm/vmstat.c index c81321f..a9d23c3 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -746,8 +746,8 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat, "\n batch: %i", i, pageset->pcp.count, - pageset->pcp.high, - pageset->pcp.batch); + zone->pcp_high, + zone->pcp_batch); #ifdef CONFIG_SMP seq_printf(m, "\n vm stats threshold: %d", pageset->stat_threshold); -- 1.6.3.3 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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