The patch titled Subject: mm: fix-up zone present pages has been removed from the -mm tree. Its filename was mm-fix-up-zone-present-pages.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Jianguo Wu <wujianguo@xxxxxxxxxx> Subject: mm: fix-up zone present pages 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 is 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 offlining 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] becomes 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 the 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 on x86_64 and IA64 platforms. Signed-off-by: Jianguo Wu <wujianguo@xxxxxxxxxx> Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxx> Reported-by: Petr Tesarik <ptesarik@xxxxxxx> Tested-by: Petr Tesarik <ptesarik@xxxxxxx> Cc: "Luck, Tony" <tony.luck@xxxxxxxxx> Cc: Mel Gorman <mel@xxxxxxxxx> Cc: Yinghai Lu <yinghai@xxxxxxxxxx> Cc: Minchan Kim <minchan.kim@xxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: David Rientjes <rientjes@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/ia64/mm/init.c | 1 + include/linux/mm.h | 4 ++++ mm/bootmem.c | 10 +++++++++- mm/memory_hotplug.c | 7 +++++++ mm/nobootmem.c | 3 +++ mm/page_alloc.c | 34 ++++++++++++++++++++++++++++++++++ 6 files changed, 58 insertions(+), 1 deletion(-) diff -puN arch/ia64/mm/init.c~mm-fix-up-zone-present-pages arch/ia64/mm/init.c --- a/arch/ia64/mm/init.c~mm-fix-up-zone-present-pages +++ a/arch/ia64/mm/init.c @@ -637,6 +637,7 @@ mem_init (void) high_memory = __va(max_low_pfn * PAGE_SIZE); + reset_zone_present_pages(); for_each_online_pgdat(pgdat) if (pgdat->bdata->node_bootmem_map) totalram_pages += free_all_bootmem_node(pgdat); diff -puN include/linux/mm.h~mm-fix-up-zone-present-pages include/linux/mm.h --- a/include/linux/mm.h~mm-fix-up-zone-present-pages +++ a/include/linux/mm.h @@ -1684,5 +1684,9 @@ static inline unsigned int debug_guardpa 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 -puN mm/bootmem.c~mm-fix-up-zone-present-pages mm/bootmem.c --- a/mm/bootmem.c~mm-fix-up-zone-present-pages +++ a/mm/bootmem.c @@ -198,6 +198,8 @@ static unsigned long __init free_all_boo 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 +210,9 @@ static unsigned long __init free_all_boo 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 +226,11 @@ static unsigned long __init free_all_boo 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 -puN mm/memory_hotplug.c~mm-fix-up-zone-present-pages mm/memory_hotplug.c --- a/mm/memory_hotplug.c~mm-fix-up-zone-present-pages +++ a/mm/memory_hotplug.c @@ -106,6 +106,7 @@ static void get_page_bootmem(unsigned lo 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 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 -puN mm/nobootmem.c~mm-fix-up-zone-present-pages mm/nobootmem.c --- a/mm/nobootmem.c~mm-fix-up-zone-present-pages +++ a/mm/nobootmem.c @@ -116,6 +116,8 @@ static unsigned long __init __free_memor 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_cor 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 -puN mm/page_alloc.c~mm-fix-up-zone-present-pages mm/page_alloc.c --- a/mm/page_alloc.c~mm-fix-up-zone-present-pages +++ a/mm/page_alloc.c @@ -6087,3 +6087,37 @@ 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); + } +} _ Patches currently in -mm which might be from wujianguo@xxxxxxxxxx are origin.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html