Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752203Ab2HTGiU (ORCPT ); Mon, 20 Aug 2012 02:38:20 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:48315 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751499Ab2HTGiS (ORCPT ); Mon, 20 Aug 2012 02:38:18 -0400 Message-ID: <5031DB52.9030806@gmail.com> Date: Mon, 20 Aug 2012 14:38:10 +0800 From: wujianguo User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:14.0) Gecko/20120713 Thunderbird/14.0 MIME-Version: 1.0 To: tony.luck@intel.com, fenghua.yu@intel.com, dhowells@redhat.com, tj@kernel.org, mgorman@suse.de, yinghai@kernel.org, minchan.kim@gmail.com CC: akpm@linux-foundation.org, viro@zeniv.linux.org.uk, aarcange@redhat.com, davem@davemloft.net, hannes@cmpxchg.org, liuj97@gmail.com, wency@cn.fujitsu.com, rientjes@google.com, kamezawa.hiroyu@jp.fujitsu.com, mhocko@suse.cz, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, ptesarik@suse.cz, jiang.liu@huawei.com, guohanjun@huawei.com, qiuxishi@huawei.com Subject: [PATCH]mm: fix-up zone present pages Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6834 Lines: 207 From: Jianguo Wu Hi all, I think zone->present_pages indicates pages that buddy system can management, it should be: zone->present_pages = spanned pages - absent pages - bootmem pages, but now: zone->present_pages = spanned pages - absent pages - memmap pages. spanned pages：total size, including holes. absent pages: holes. bootmem pages: pages used in system boot, managed by bootmem allocator. memmap pages: pages used by page structs. This may cause zone->present_pages less than it should be. For example, numa node 1 has ZONE_NORMAL and ZONE_MOVABLE, it's memmap and other bootmem will be allocated from ZONE_MOVABLE, so ZONE_NORMAL's present_pages should be spanned pages - absent pages, but now it also minus memmap pages(free_area_init_core), which are actually allocated from ZONE_MOVABLE. When offline all memory of a zone, This will cause zone->present_pages less than 0, because present_pages is unsigned long type, it is actually a very large integer, it indirectly caused zone->watermark[WMARK_MIN] become a large integer(setup_per_zone_wmarks()), than cause totalreserve_pages become a large integer(calculate_totalreserve_pages()), and finally cause memory allocating failure when fork process(__vm_enough_memory()). [root@localhost ~]# dmesg -bash: fork: Cannot allocate memory I think bug described in http://marc.info/?l=linux-mm&m=134502182714186&w=2 is also caused by wrong zone present pages. This patch intends to fix-up zone->present_pages when memory are freed to buddy system in x86_64 and IA64 platform. Thanks. Signed-off-by: Jianguo Wu Signed-off-by: Jiang Liu --- arch/ia64/mm/init.c | 1 + include/linux/mm.h | 4 ++++ mm/bootmem.c | 9 ++++++++- mm/memory_hotplug.c | 7 +++++++ mm/nobootmem.c | 3 +++ mm/page_alloc.c | 34 ++++++++++++++++++++++++++++++++++ 6 files changed, 57 insertions(+), 1 deletions(-) diff --git a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c index b960ba0..c78e3fd 100644 --- a/arch/ia64/mm/init.c +++ b/arch/ia64/mm/init.c @@ -640,6 +640,7 @@ mem_init (void) free_floating_node_bootmem(); #endif + reset_zone_present_pages(); for_each_online_pgdat(pgdat) if (pgdat->bdata->node_bootmem_map) totalram_pages += free_all_bootmem_node(pgdat); diff --git a/include/linux/mm.h b/include/linux/mm.h index 311be90..a1bd8ea 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1662,5 +1662,9 @@ static inline unsigned int debug_guardpage_minorder(void) { return 0; } static inline bool page_is_guard(struct page *page) { return false; } #endif /* CONFIG_DEBUG_PAGEALLOC */ +extern void reset_zone_present_pages(void); +extern void fixup_zone_present_pages(int nid, unsigned long start_pfn, + unsigned long end_pfn); + #endif /* __KERNEL__ */ #endif /* _LINUX_MM_H */ diff --git a/mm/bootmem.c b/mm/bootmem.c index bcb63ac..e00b491 100644 --- a/mm/bootmem.c +++ b/mm/bootmem.c @@ -198,6 +198,8 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata) int order = ilog2(BITS_PER_LONG); __free_pages_bootmem(pfn_to_page(start), order); + fixup_zone_present_pages(page_to_nid(pfn_to_page(start)), + start, start + BITS_PER_LONG); count += BITS_PER_LONG; start += BITS_PER_LONG; } else { @@ -208,6 +210,8 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata) if (vec & 1) { page = pfn_to_page(start + off); __free_pages_bootmem(page, 0); + fixup_zone_present_pages(page_to_nid(page), + start + off, start + off + 1); count++; } vec >>= 1; @@ -221,8 +225,11 @@ static unsigned long __init free_all_bootmem_core(bootmem_data_t *bdata) pages = bdata->node_low_pfn - bdata->node_min_pfn; pages = bootmem_bootmap_pages(pages); count += pages; - while (pages--) + while (pages--) { + fixup_zone_present_pages(page_to_nid(page), + page_to_pfn(page), page_to_pfn(page) + 1); __free_pages_bootmem(page++, 0); + } bdebug("nid=%td released=%lx\n", bdata - bootmem_node_data, count); diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index 3ad25f9..bc7e7a2 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; + struct zone *zone; type = (unsigned long) page->lru.next; BUG_ON(type < MEMORY_HOTPLUG_MIN_BOOTMEM_TYPE || @@ -116,6 +117,12 @@ void __ref put_page_bootmem(struct page *page) set_page_private(page, 0); INIT_LIST_HEAD(&page->lru); __free_pages_bootmem(page, 0); + + zone = page_zone(page); + zone_span_writelock(zone); + zone->present_pages++; + zone_span_writeunlock(zone); + totalram_pages++; } } diff --git a/mm/nobootmem.c b/mm/nobootmem.c index 4055730..8027861 100644 --- a/mm/nobootmem.c +++ b/mm/nobootmem.c @@ -116,6 +116,8 @@ static unsigned long __init __free_memory_core(phys_addr_t start, return 0; __free_pages_memory(start_pfn, end_pfn); + fixup_zone_present_pages(pfn_to_nid(start >> PAGE_SHIFT), + start_pfn, end_pfn); return end_pfn - start_pfn; } @@ -126,6 +128,7 @@ unsigned long __init free_low_memory_core_early(int nodeid) phys_addr_t start, end, size; u64 i; + reset_zone_present_pages(); for_each_free_mem_range(i, MAX_NUMNODES, &start, &end, NULL) count += __free_memory_core(start, end); diff --git a/mm/page_alloc.c b/mm/page_alloc.c index fcb0932..36c35bb 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -6074,3 +6074,37 @@ void dump_page(struct page *page) dump_page_flags(page->flags); mem_cgroup_print_bad_page(page); } + +/* reset zone->present_pages */ +void reset_zone_present_pages(void) +{ + struct zone *z; + int i, nid; + + for_each_node_state(nid, N_HIGH_MEMORY) { + for (i = 0; i < MAX_NR_ZONES; i++) { + z = NODE_DATA(nid)->node_zones + i; + z->present_pages = 0; + } + } +} + +/* calculate zone's present pages in buddy system */ +void fixup_zone_present_pages(int nid, unsigned long start_pfn, + unsigned long end_pfn) +{ + struct zone *z; + unsigned long zone_start_pfn, zone_end_pfn; + int i; + + for (i = 0; i < MAX_NR_ZONES; i++) { + z = NODE_DATA(nid)->node_zones + i; + zone_start_pfn = z->zone_start_pfn; + zone_end_pfn = zone_start_pfn + z->spanned_pages; + + /* if the two regions intersect */ + if (!(zone_start_pfn >= end_pfn || zone_end_pfn <= start_pfn)) + z->present_pages += min(end_pfn, zone_end_pfn) - + max(start_pfn, zone_start_pfn); + } +} -- 1.7.6.1 . -- 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/