From bea8c150a7efbc0f204e709b7274fe273f55e0d3 Mon Sep 17 00:00:00 2001 From: Hugh Dickins Date: Fri, 16 Nov 2012 14:14:54 -0800 Subject: memcg: fix hotplugged memory zone oops When MEMCG is configured on (even when it's disabled by boot option), when adding or removing a page to/from its lru list, the zone pointer used for stats updates is nowadays taken from the struct lruvec. (On many configurations, calculating zone from page is slower.) But we have no code to update all the lruvecs (per zone, per memcg) when a memory node is hotadded. Here's an extract from the oops which results when running numactl to bind a program to a newly onlined node: BUG: unable to handle kernel NULL pointer dereference at 0000000000000f60 IP: __mod_zone_page_state+0x9/0x60 Pid: 1219, comm: numactl Not tainted 3.6.0-rc5+ #180 Bochs Bochs Process numactl (pid: 1219, threadinfo ffff880039abc000, task ffff8800383c4ce0) Call Trace: __pagevec_lru_add_fn+0xdf/0x140 pagevec_lru_move_fn+0xb1/0x100 __pagevec_lru_add+0x1c/0x30 lru_add_drain_cpu+0xa3/0x130 lru_add_drain+0x2f/0x40 ... The natural solution might be to use a memcg callback whenever memory is hotadded; but that solution has not been scoped out, and it happens that we do have an easy location at which to update lruvec->zone. The lruvec pointer is discovered either by mem_cgroup_zone_lruvec() or by mem_cgroup_page_lruvec(), and both of those do know the right zone. So check and set lruvec->zone in those; and remove the inadequate attempt to set lruvec->zone from lruvec_init(), which is called before NODE_DATA(node) has been allocated in such cases. Ah, there was one exceptionr. For no particularly good reason, mem_cgroup_force_empty_list() has its own code for deciding lruvec. Change it to use the standard mem_cgroup_zone_lruvec() and mem_cgroup_get_lru_size() too. In fact it was already safe against such an oops (the lru lists in danger could only be empty), but we're better proofed against future changes this way. I've marked this for stable (3.6) since we introduced the problem in 3.5 (now closed to stable); but I have no idea if this is the only fix needed to get memory hotadd working with memcg in 3.6, and received no answer when I enquired twice before. Reported-by: Tang Chen Signed-off-by: Hugh Dickins Acked-by: Johannes Weiner Acked-by: KAMEZAWA Hiroyuki Cc: Konstantin Khlebnikov Cc: Wen Congyang Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mmzone.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include/linux/mmzone.h') diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 50aaca81f63d..a23923ba8263 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -752,7 +752,7 @@ extern int init_currently_empty_zone(struct zone *zone, unsigned long start_pfn, unsigned long size, enum memmap_context context); -extern void lruvec_init(struct lruvec *lruvec, struct zone *zone); +extern void lruvec_init(struct lruvec *lruvec); static inline struct zone *lruvec_zone(struct lruvec *lruvec) { -- cgit v1.2.3 From 8177a420ed7c16c171ed3c3aec5b0676db38c247 Mon Sep 17 00:00:00 2001 From: Andrea Arcangeli Date: Fri, 23 Mar 2012 20:56:34 +0100 Subject: mm: numa: Structures for Migrate On Fault per NUMA migration rate limiting This defines the per-node data used by Migrate On Fault in order to rate limit the migration. The rate limiting is applied independently to each destination node. Signed-off-by: Andrea Arcangeli Signed-off-by: Mel Gorman --- include/linux/mmzone.h | 13 +++++++++++++ mm/page_alloc.c | 5 +++++ 2 files changed, 18 insertions(+) (limited to 'include/linux/mmzone.h') diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index a23923ba8263..28601fdfcdb2 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -717,6 +717,19 @@ typedef struct pglist_data { struct task_struct *kswapd; /* Protected by lock_memory_hotplug() */ int kswapd_max_order; enum zone_type classzone_idx; +#ifdef CONFIG_NUMA_BALANCING + /* + * Lock serializing the per destination node AutoNUMA memory + * migration rate limiting data. + */ + spinlock_t numabalancing_migrate_lock; + + /* Rate limiting time interval */ + unsigned long numabalancing_migrate_next_window; + + /* Number of pages migrated during the rate limiting time interval */ + unsigned long numabalancing_migrate_nr_pages; +#endif } pg_data_t; #define node_present_pages(nid) (NODE_DATA(nid)->node_present_pages) diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 5953dc2d196f..ef025e20dbee 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -4449,6 +4449,11 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat, int ret; pgdat_resize_init(pgdat); +#ifdef CONFIG_NUMA_BALANCING + spin_lock_init(&pgdat->numabalancing_migrate_lock); + pgdat->numabalancing_migrate_nr_pages = 0; + pgdat->numabalancing_migrate_next_window = jiffies; +#endif init_waitqueue_head(&pgdat->kswapd_wait); init_waitqueue_head(&pgdat->pfmemalloc_wait); pgdat_page_cgroup_init(pgdat); -- cgit v1.2.3 From bc357f431c836c6631751e3ef7dfe7882394ad67 Mon Sep 17 00:00:00 2001 From: Marek Szyprowski Date: Tue, 11 Dec 2012 16:02:59 -0800 Subject: mm: cma: remove watermark hacks Commits 2139cbe627b8 ("cma: fix counting of isolated pages") and d95ea5d18e69 ("cma: fix watermark checking") introduced a reliable method of free page accounting when memory is being allocated from CMA regions, so the workaround introduced earlier by commit 49f223a9cd96 ("mm: trigger page reclaim in alloc_contig_range() to stabilise watermarks") can be finally removed. Signed-off-by: Marek Szyprowski Cc: Kyungmin Park Cc: Arnd Bergmann Cc: Mel Gorman Acked-by: Michal Nazarewicz Cc: Minchan Kim Cc: Bartlomiej Zolnierkiewicz Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mmzone.h | 9 -------- mm/page_alloc.c | 58 -------------------------------------------------- 2 files changed, 67 deletions(-) (limited to 'include/linux/mmzone.h') diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index a23923ba8263..0c0b1d608a69 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -63,10 +63,8 @@ enum { #ifdef CONFIG_CMA # define is_migrate_cma(migratetype) unlikely((migratetype) == MIGRATE_CMA) -# define cma_wmark_pages(zone) zone->min_cma_pages #else # define is_migrate_cma(migratetype) false -# define cma_wmark_pages(zone) 0 #endif #define for_each_migratetype_order(order, type) \ @@ -382,13 +380,6 @@ struct zone { #ifdef CONFIG_MEMORY_HOTPLUG /* see spanned/present_pages for more description */ seqlock_t span_seqlock; -#endif -#ifdef CONFIG_CMA - /* - * CMA needs to increase watermark levels during the allocation - * process to make sure that the system is not starved. - */ - unsigned long min_cma_pages; #endif struct free_area free_area[MAX_ORDER]; diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 265fea4fbc81..5a8d339d282a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -5218,10 +5218,6 @@ static void __setup_per_zone_wmarks(void) zone->watermark[WMARK_LOW] = min_wmark_pages(zone) + (tmp >> 2); zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + (tmp >> 1); - zone->watermark[WMARK_MIN] += cma_wmark_pages(zone); - zone->watermark[WMARK_LOW] += cma_wmark_pages(zone); - zone->watermark[WMARK_HIGH] += cma_wmark_pages(zone); - setup_zone_migrate_reserve(zone); spin_unlock_irqrestore(&zone->lock, flags); } @@ -5766,54 +5762,6 @@ static int __alloc_contig_migrate_range(struct compact_control *cc, return ret > 0 ? 0 : ret; } -/* - * Update zone's cma pages counter used for watermark level calculation. - */ -static inline void __update_cma_watermarks(struct zone *zone, int count) -{ - unsigned long flags; - spin_lock_irqsave(&zone->lock, flags); - zone->min_cma_pages += count; - spin_unlock_irqrestore(&zone->lock, flags); - setup_per_zone_wmarks(); -} - -/* - * Trigger memory pressure bump to reclaim some pages in order to be able to - * allocate 'count' pages in single page units. Does similar work as - *__alloc_pages_slowpath() function. - */ -static int __reclaim_pages(struct zone *zone, gfp_t gfp_mask, int count) -{ - enum zone_type high_zoneidx = gfp_zone(gfp_mask); - struct zonelist *zonelist = node_zonelist(0, gfp_mask); - int did_some_progress = 0; - int order = 1; - - /* - * Increase level of watermarks to force kswapd do his job - * to stabilise at new watermark level. - */ - __update_cma_watermarks(zone, count); - - /* Obey watermarks as if the page was being allocated */ - while (!zone_watermark_ok(zone, 0, low_wmark_pages(zone), 0, 0)) { - wake_all_kswapd(order, zonelist, high_zoneidx, zone_idx(zone)); - - did_some_progress = __perform_reclaim(gfp_mask, order, zonelist, - NULL); - if (!did_some_progress) { - /* Exhausted what can be done so it's blamo time */ - out_of_memory(zonelist, gfp_mask, order, NULL, false); - } - } - - /* Restore original watermark levels. */ - __update_cma_watermarks(zone, -count); - - return count; -} - /** * alloc_contig_range() -- tries to allocate given range of pages * @start: start PFN to allocate @@ -5837,7 +5785,6 @@ static int __reclaim_pages(struct zone *zone, gfp_t gfp_mask, int count) int alloc_contig_range(unsigned long start, unsigned long end, unsigned migratetype) { - struct zone *zone = page_zone(pfn_to_page(start)); unsigned long outer_start, outer_end; int ret = 0, order; @@ -5922,11 +5869,6 @@ int alloc_contig_range(unsigned long start, unsigned long end, goto done; } - /* - * Reclaim enough pages to make sure that contiguous allocation - * will not starve the system. - */ - __reclaim_pages(zone, GFP_HIGHUSER_MOVABLE, end-start); /* Grab isolated pages from freelists. */ outer_end = isolate_freepages_range(&cc, outer_start, end); -- cgit v1.2.3 From 9feedc9d831e18ae6d0d15aa562e5e46ba53647b Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Wed, 12 Dec 2012 13:52:12 -0800 Subject: mm: introduce new field "managed_pages" to struct zone Currently a zone's present_pages is calcuated as below, which is inaccurate and may cause trouble to memory hotplug. spanned_pages - absent_pages - memmap_pages - dma_reserve. During fixing bugs caused by inaccurate zone->present_pages, we found zone->present_pages has been abused. The field zone->present_pages may have different meanings in different contexts: 1) pages existing in a zone. 2) pages managed by the buddy system. For more discussions about the issue, please refer to: http://lkml.org/lkml/2012/11/5/866 https://patchwork.kernel.org/patch/1346751/ This patchset tries to introduce a new field named "managed_pages" to struct zone, which counts "pages managed by the buddy system". And revert zone->present_pages to count "physical pages existing in a zone", which also keep in consistence with pgdat->node_present_pages. We will set an initial value for zone->managed_pages in function free_area_init_core() and will adjust it later if the initial value is inaccurate. For DMA/normal zones, the initial value is set to: (spanned_pages - absent_pages - memmap_pages - dma_reserve) Later zone->managed_pages will be adjusted to the accurate value when the bootmem allocator frees all free pages to the buddy system in function free_all_bootmem_node() and free_all_bootmem(). The bootmem allocator doesn't touch highmem pages, so highmem zones' managed_pages is set to the accurate value "spanned_pages - absent_pages" in function free_area_init_core() and won't be updated anymore. This patch also adds a new field "managed_pages" to /proc/zoneinfo and sysrq showmem. [akpm@linux-foundation.org: small comment tweaks] Signed-off-by: Jiang Liu Cc: Wen Congyang Cc: David Rientjes Cc: Maciej Rutecki Tested-by: Chris Clayton Cc: "Rafael J . Wysocki" Cc: Mel Gorman Cc: Minchan Kim Cc: KAMEZAWA Hiroyuki Cc: Michal Hocko Cc: Jianguo Wu Cc: Johannes Weiner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mmzone.h | 41 ++++++++++++++++++++++++++++++++++------- mm/bootmem.c | 21 +++++++++++++++++++++ mm/memory_hotplug.c | 10 ++++++++++ mm/nobootmem.c | 22 ++++++++++++++++++++++ mm/page_alloc.c | 44 ++++++++++++++++++++++++++++++-------------- mm/vmstat.c | 6 ++++-- 6 files changed, 121 insertions(+), 23 deletions(-) (limited to 'include/linux/mmzone.h') diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 0c0b1d608a69..cd55dad56aac 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -460,17 +460,44 @@ struct zone { unsigned long zone_start_pfn; /* - * zone_start_pfn, spanned_pages and present_pages are all - * protected by span_seqlock. It is a seqlock because it has - * to be read outside of zone->lock, and it is done in the main - * allocator path. But, it is written quite infrequently. + * spanned_pages is the total pages spanned by the zone, including + * holes, which is calculated as: + * spanned_pages = zone_end_pfn - zone_start_pfn; * - * The lock is declared along with zone->lock because it is + * present_pages is physical pages existing within the zone, which + * is calculated as: + * present_pages = spanned_pages - absent_pages(pags in holes); + * + * managed_pages is present pages managed by the buddy system, which + * is calculated as (reserved_pages includes pages allocated by the + * bootmem allocator): + * managed_pages = present_pages - reserved_pages; + * + * So present_pages may be used by memory hotplug or memory power + * management logic to figure out unmanaged pages by checking + * (present_pages - managed_pages). And managed_pages should be used + * by page allocator and vm scanner to calculate all kinds of watermarks + * and thresholds. + * + * Locking rules: + * + * zone_start_pfn and spanned_pages are protected by span_seqlock. + * It is a seqlock because it has to be read outside of zone->lock, + * and it is done in the main allocator path. But, it is written + * quite infrequently. + * + * The span_seq lock is declared along with zone->lock because it is * frequently read in proximity to zone->lock. It's good to * give them a chance of being in the same cacheline. + * + * Write access to present_pages and managed_pages at runtime should + * be protected by lock_memory_hotplug()/unlock_memory_hotplug(). + * Any reader who can't tolerant drift of present_pages and + * managed_pages should hold memory hotplug lock to get a stable value. */ - unsigned long spanned_pages; /* total size, including holes */ - unsigned long present_pages; /* amount of memory (excluding holes) */ + unsigned long spanned_pages; + unsigned long present_pages; + unsigned long managed_pages; /* * rarely used fields: diff --git a/mm/bootmem.c b/mm/bootmem.c index 26d057a8b552..19262ac05dd2 100644 --- a/mm/bootmem.c +++ b/mm/bootmem.c @@ -229,6 +229,22 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata) return count; } +static void reset_node_lowmem_managed_pages(pg_data_t *pgdat) +{ + struct zone *z; + + /* + * In free_area_init_core(), highmem zone's managed_pages is set to + * present_pages, and bootmem allocator doesn't allocate from highmem + * zones. So there's no need to recalculate managed_pages because all + * highmem pages will be managed by the buddy system. Here highmem + * zone also includes highmem movable zone. + */ + for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++) + if (!is_highmem(z)) + z->managed_pages = 0; +} + /** * free_all_bootmem_node - release a node's free pages to the buddy allocator * @pgdat: node to be released @@ -238,6 +254,7 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata) unsigned long __init free_all_bootmem_node(pg_data_t *pgdat) { register_page_bootmem_info_node(pgdat); + reset_node_lowmem_managed_pages(pgdat); return free_all_bootmem_core(pgdat->bdata); } @@ -250,6 +267,10 @@ unsigned long __init free_all_bootmem(void) { unsigned long total_pages = 0; bootmem_data_t *bdata; + struct pglist_data *pgdat; + + for_each_online_pgdat(pgdat) + reset_node_lowmem_managed_pages(pgdat); list_for_each_entry(bdata, &bdata_list, list) total_pages += free_all_bootmem_core(bdata); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index c6cd8b515424..b7c93ca896d6 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -106,6 +106,7 @@ static void get_page_bootmem(unsigned long info, struct page *page, void __ref put_page_bootmem(struct page *page) { unsigned long type; + static DEFINE_MUTEX(ppb_lock); type = (unsigned long) page->lru.next; BUG_ON(type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE || @@ -115,7 +116,14 @@ void __ref put_page_bootmem(struct page *page) ClearPagePrivate(page); set_page_private(page, 0); INIT_LIST_HEAD(&page->lru); + + /* + * Please refer to comment for __free_pages_bootmem() + * for why we serialize here. + */ + mutex_lock(&ppb_lock); __free_pages_bootmem(page, 0); + mutex_unlock(&ppb_lock); } } @@ -748,6 +756,7 @@ int __ref online_pages(unsigned long pfn, unsigned long nr_pages, int online_typ return ret; } + zone->managed_pages += onlined_pages; zone->present_pages += onlined_pages; zone->zone_pgdat->node_present_pages += onlined_pages; if (onlined_pages) { @@ -1321,6 +1330,7 @@ repeat: /* reset pagetype flags and makes migrate type to be MOVABLE */ undo_isolate_page_range(start_pfn, end_pfn, MIGRATE_MOVABLE); /* removal success */ + zone->managed_pages -= offlined_pages; zone->present_pages -= offlined_pages; zone->zone_pgdat->node_present_pages -= offlined_pages; totalram_pages -= offlined_pages; diff --git a/mm/nobootmem.c b/mm/nobootmem.c index bd82f6b31411..b8294fc03df8 100644 --- a/mm/nobootmem.c +++ b/mm/nobootmem.c @@ -137,6 +137,22 @@ unsigned long __init free_low_memory_core_early(int nodeid) return count; } +static void reset_node_lowmem_managed_pages(pg_data_t *pgdat) +{ + struct zone *z; + + /* + * In free_area_init_core(), highmem zone's managed_pages is set to + * present_pages, and bootmem allocator doesn't allocate from highmem + * zones. So there's no need to recalculate managed_pages because all + * highmem pages will be managed by the buddy system. Here highmem + * zone also includes highmem movable zone. + */ + for (z = pgdat->node_zones; z < pgdat->node_zones + MAX_NR_ZONES; z++) + if (!is_highmem(z)) + z->managed_pages = 0; +} + /** * free_all_bootmem_node - release a node's free pages to the buddy allocator * @pgdat: node to be released @@ -146,6 +162,7 @@ unsigned long __init free_low_memory_core_early(int nodeid) unsigned long __init free_all_bootmem_node(pg_data_t *pgdat) { register_page_bootmem_info_node(pgdat); + reset_node_lowmem_managed_pages(pgdat); /* free_low_memory_core_early(MAX_NUMNODES) will be called later */ return 0; @@ -158,6 +175,11 @@ unsigned long __init free_all_bootmem_node(pg_data_t *pgdat) */ unsigned long __init free_all_bootmem(void) { + struct pglist_data *pgdat; + + for_each_online_pgdat(pgdat) + reset_node_lowmem_managed_pages(pgdat); + /* * We need to use MAX_NUMNODES instead of NODE_DATA(0)->node_id * because in some case like Node0 doesn't have RAM installed diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 2bf0d43d646b..0b6a6d04300a 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -735,6 +735,13 @@ static void __free_pages_ok(struct page *page, unsigned int order) local_irq_restore(flags); } +/* + * Read access to zone->managed_pages is safe because it's unsigned long, + * but we still need to serialize writers. Currently all callers of + * __free_pages_bootmem() except put_page_bootmem() should only be used + * at boot time. So for shorter boot time, we shift the burden to + * put_page_bootmem() to serialize writers. + */ void __meminit __free_pages_bootmem(struct page *page, unsigned int order) { unsigned int nr_pages = 1 << order; @@ -750,6 +757,7 @@ void __meminit __free_pages_bootmem(struct page *page, unsigned int order) set_page_count(p, 0); } + page_zone(page)->managed_pages += 1 << order; set_page_refcounted(page); __free_pages(page, order); } @@ -2984,6 +2992,7 @@ void show_free_areas(unsigned int filter) " isolated(anon):%lukB" " isolated(file):%lukB" " present:%lukB" + " managed:%lukB" " mlocked:%lukB" " dirty:%lukB" " writeback:%lukB" @@ -3013,6 +3022,7 @@ void show_free_areas(unsigned int filter) K(zone_page_state(zone, NR_ISOLATED_ANON)), K(zone_page_state(zone, NR_ISOLATED_FILE)), K(zone->present_pages), + K(zone->managed_pages), K(zone_page_state(zone, NR_MLOCK)), K(zone_page_state(zone, NR_FILE_DIRTY)), K(zone_page_state(zone, NR_WRITEBACK)), @@ -4502,48 +4512,54 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat, for (j = 0; j < MAX_NR_ZONES; j++) { struct zone *zone = pgdat->node_zones + j; - unsigned long size, realsize, memmap_pages; + unsigned long size, realsize, freesize, memmap_pages; size = zone_spanned_pages_in_node(nid, j, zones_size); - realsize = size - zone_absent_pages_in_node(nid, j, + realsize = freesize = size - zone_absent_pages_in_node(nid, j, zholes_size); /* - * Adjust realsize so that it accounts for how much memory + * Adjust freesize so that it accounts for how much memory * is used by this zone for memmap. This affects the watermark * and per-cpu initialisations */ memmap_pages = PAGE_ALIGN(size * sizeof(struct page)) >> PAGE_SHIFT; - if (realsize >= memmap_pages) { - realsize -= memmap_pages; + if (freesize >= memmap_pages) { + freesize -= memmap_pages; if (memmap_pages) printk(KERN_DEBUG " %s zone: %lu pages used for memmap\n", zone_names[j], memmap_pages); } else printk(KERN_WARNING - " %s zone: %lu pages exceeds realsize %lu\n", - zone_names[j], memmap_pages, realsize); + " %s zone: %lu pages exceeds freesize %lu\n", + zone_names[j], memmap_pages, freesize); /* Account for reserved pages */ - if (j == 0 && realsize > dma_reserve) { - realsize -= dma_reserve; + if (j == 0 && freesize > dma_reserve) { + freesize -= dma_reserve; printk(KERN_DEBUG " %s zone: %lu pages reserved\n", zone_names[0], dma_reserve); } if (!is_highmem_idx(j)) - nr_kernel_pages += realsize; - nr_all_pages += realsize; + nr_kernel_pages += freesize; + nr_all_pages += freesize; zone->spanned_pages = size; - zone->present_pages = realsize; + zone->present_pages = freesize; + /* + * Set an approximate value for lowmem here, it will be adjusted + * when the bootmem allocator frees pages into the buddy system. + * And all highmem pages will be managed by the buddy system. + */ + zone->managed_pages = is_highmem_idx(j) ? realsize : freesize; #ifdef CONFIG_NUMA zone->node = nid; - zone->min_unmapped_pages = (realsize*sysctl_min_unmapped_ratio) + zone->min_unmapped_pages = (freesize*sysctl_min_unmapped_ratio) / 100; - zone->min_slab_pages = (realsize * sysctl_min_slab_ratio) / 100; + zone->min_slab_pages = (freesize * sysctl_min_slab_ratio) / 100; #endif zone->name = zone_names[j]; spin_lock_init(&zone->lock); diff --git a/mm/vmstat.c b/mm/vmstat.c index 9a4a522c0b0f..df14808f0a36 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -994,14 +994,16 @@ static void zoneinfo_show_print(struct seq_file *m, pg_data_t *pgdat, "\n high %lu" "\n scanned %lu" "\n spanned %lu" - "\n present %lu", + "\n present %lu" + "\n managed %lu", zone_page_state(zone, NR_FREE_PAGES), min_wmark_pages(zone), low_wmark_pages(zone), high_wmark_pages(zone), zone->pages_scanned, zone->spanned_pages, - zone->present_pages); + zone->present_pages, + zone->managed_pages); for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++) seq_printf(m, "\n %-12s %lu", vmstat_text[i], -- cgit v1.2.3 From a458431e176ddb27e8ef8b98c2a681b217337393 Mon Sep 17 00:00:00 2001 From: Bartlomiej Zolnierkiewicz Date: Fri, 4 Jan 2013 15:35:08 -0800 Subject: mm: fix zone_watermark_ok_safe() accounting of isolated pages Commit 702d1a6e0766 ("memory-hotplug: fix kswapd looping forever problem") added an isolated pageblocks counter (nr_pageblock_isolate in struct zone) and used it to adjust free pages counter in zone_watermark_ok_safe() to prevent kswapd looping forever problem. Then later, commit 2139cbe627b8 ("cma: fix counting of isolated pages") fixed accounting of isolated pages in global free pages counter. It made the previous zone_watermark_ok_safe() fix unnecessary and potentially harmful (cause now isolated pages may be accounted twice making free pages counter incorrect). This patch removes the special isolated pageblocks counter altogether which fixes zone_watermark_ok_safe() free pages check. Reported-by: Tomasz Stanislawski Signed-off-by: Bartlomiej Zolnierkiewicz Signed-off-by: Kyungmin Park Cc: Minchan Kim Cc: KOSAKI Motohiro Cc: Aaditya Kumar Cc: KAMEZAWA Hiroyuki Cc: Mel Gorman Cc: Michal Hocko Cc: Marek Szyprowski Cc: Michal Nazarewicz Cc: Hugh Dickins Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/mmzone.h | 8 -------- mm/page_alloc.c | 27 --------------------------- mm/page_isolation.c | 26 ++------------------------ 3 files changed, 2 insertions(+), 59 deletions(-) (limited to 'include/linux/mmzone.h') diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 4bec5be82cab..73b64a38b984 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -503,14 +503,6 @@ struct zone { * rarely used fields: */ const char *name; -#ifdef CONFIG_MEMORY_ISOLATION - /* - * the number of MIGRATE_ISOLATE *pageblock*. - * We need this for free page counting. Look at zone_watermark_ok_safe. - * It's protected by zone->lock - */ - int nr_pageblock_isolate; -#endif } ____cacheline_internodealigned_in_smp; typedef enum { diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 4ba5e37127fc..bc6cc0e913bd 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -221,11 +221,6 @@ EXPORT_SYMBOL(nr_online_nodes); int page_group_by_mobility_disabled __read_mostly; -/* - * NOTE: - * Don't use set_pageblock_migratetype(page, MIGRATE_ISOLATE) directly. - * Instead, use {un}set_pageblock_isolate. - */ void set_pageblock_migratetype(struct page *page, int migratetype) { @@ -1655,20 +1650,6 @@ static bool __zone_watermark_ok(struct zone *z, int order, unsigned long mark, return true; } -#ifdef CONFIG_MEMORY_ISOLATION -static inline unsigned long nr_zone_isolate_freepages(struct zone *zone) -{ - if (unlikely(zone->nr_pageblock_isolate)) - return zone->nr_pageblock_isolate * pageblock_nr_pages; - return 0; -} -#else -static inline unsigned long nr_zone_isolate_freepages(struct zone *zone) -{ - return 0; -} -#endif - bool zone_watermark_ok(struct zone *z, int order, unsigned long mark, int classzone_idx, int alloc_flags) { @@ -1684,14 +1665,6 @@ bool zone_watermark_ok_safe(struct zone *z, int order, unsigned long mark, if (z->percpu_drift_mark && free_pages < z->percpu_drift_mark) free_pages = zone_page_state_snapshot(z, NR_FREE_PAGES); - /* - * If the zone has MIGRATE_ISOLATE type free pages, we should consider - * it. nr_zone_isolate_freepages is never accurate so kswapd might not - * sleep although it could do so. But this is more desirable for memory - * hotplug than sleeping which can cause a livelock in the direct - * reclaim path. - */ - free_pages -= nr_zone_isolate_freepages(z); return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags, free_pages); } diff --git a/mm/page_isolation.c b/mm/page_isolation.c index 9d2264ea4606..383bdbb98b04 100644 --- a/mm/page_isolation.c +++ b/mm/page_isolation.c @@ -8,28 +8,6 @@ #include #include "internal.h" -/* called while holding zone->lock */ -static void set_pageblock_isolate(struct page *page) -{ - if (get_pageblock_migratetype(page) == MIGRATE_ISOLATE) - return; - - set_pageblock_migratetype(page, MIGRATE_ISOLATE); - page_zone(page)->nr_pageblock_isolate++; -} - -/* called while holding zone->lock */ -static void restore_pageblock_isolate(struct page *page, int migratetype) -{ - struct zone *zone = page_zone(page); - if (WARN_ON(get_pageblock_migratetype(page) != MIGRATE_ISOLATE)) - return; - - BUG_ON(zone->nr_pageblock_isolate <= 0); - set_pageblock_migratetype(page, migratetype); - zone->nr_pageblock_isolate--; -} - int set_migratetype_isolate(struct page *page, bool skip_hwpoisoned_pages) { struct zone *zone; @@ -80,7 +58,7 @@ out: unsigned long nr_pages; int migratetype = get_pageblock_migratetype(page); - set_pageblock_isolate(page); + set_pageblock_migratetype(page, MIGRATE_ISOLATE); nr_pages = move_freepages_block(zone, page, MIGRATE_ISOLATE); __mod_zone_freepage_state(zone, -nr_pages, migratetype); @@ -103,7 +81,7 @@ void unset_migratetype_isolate(struct page *page, unsigned migratetype) goto out; nr_pages = move_freepages_block(zone, page, migratetype); __mod_zone_freepage_state(zone, nr_pages, migratetype); - restore_pageblock_isolate(page, migratetype); + set_pageblock_migratetype(page, migratetype); out: spin_unlock_irqrestore(&zone->lock, flags); } -- cgit v1.2.3