| /* |
| * linux/mm/page_alloc.c |
| * |
| * Manages the free list, the system allocates free pages here. |
| * Note that kmalloc() lives in slab.c |
| * |
| * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds |
| * Swap reorganised 29.12.95, Stephen Tweedie |
| * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999 |
| * Reshaped it to be a zoned allocator, Ingo Molnar, Red Hat, 1999 |
| * Discontiguous memory support, Kanoj Sarcar, SGI, Nov 1999 |
| * Zone balancing, Kanoj Sarcar, SGI, Jan 2000 |
| * Per cpu hot/cold page lists, bulk allocation, Martin J. Bligh, Sept 2002 |
| * (lots of bits borrowed from Ingo Molnar & Andrew Morton) |
| */ |
| |
| #include <linux/stddef.h> |
| #include <linux/mm.h> |
| #include <linux/swap.h> |
| #include <linux/interrupt.h> |
| #include <linux/pagemap.h> |
| #include <linux/jiffies.h> |
| #include <linux/bootmem.h> |
| #include <linux/memblock.h> |
| #include <linux/compiler.h> |
| #include <linux/kernel.h> |
| #include <linux/kmemcheck.h> |
| #include <linux/kasan.h> |
| #include <linux/module.h> |
| #include <linux/suspend.h> |
| #include <linux/pagevec.h> |
| #include <linux/blkdev.h> |
| #include <linux/slab.h> |
| #include <linux/ratelimit.h> |
| #include <linux/oom.h> |
| #include <linux/notifier.h> |
| #include <linux/topology.h> |
| #include <linux/sysctl.h> |
| #include <linux/cpu.h> |
| #include <linux/cpuset.h> |
| #include <linux/memory_hotplug.h> |
| #include <linux/nodemask.h> |
| #include <linux/vmalloc.h> |
| #include <linux/vmstat.h> |
| #include <linux/mempolicy.h> |
| #include <linux/memremap.h> |
| #include <linux/stop_machine.h> |
| #include <linux/sort.h> |
| #include <linux/pfn.h> |
| #include <linux/backing-dev.h> |
| #include <linux/fault-inject.h> |
| #include <linux/page-isolation.h> |
| #include <linux/page_ext.h> |
| #include <linux/debugobjects.h> |
| #include <linux/kmemleak.h> |
| #include <linux/compaction.h> |
| #include <trace/events/kmem.h> |
| #include <linux/prefetch.h> |
| #include <linux/mm_inline.h> |
| #include <linux/migrate.h> |
| #include <linux/page_ext.h> |
| #include <linux/hugetlb.h> |
| #include <linux/sched/rt.h> |
| #include <linux/page_owner.h> |
| #include <linux/kthread.h> |
| #include <linux/memcontrol.h> |
| |
| #include <asm/sections.h> |
| #include <asm/tlbflush.h> |
| #include <asm/div64.h> |
| #include "internal.h" |
| |
| /* prevent >1 _updater_ of zone percpu pageset ->high and ->batch fields */ |
| static DEFINE_MUTEX(pcp_batch_high_lock); |
| #define MIN_PERCPU_PAGELIST_FRACTION (8) |
| |
| #ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID |
| DEFINE_PER_CPU(int, numa_node); |
| EXPORT_PER_CPU_SYMBOL(numa_node); |
| #endif |
| |
| #ifdef CONFIG_HAVE_MEMORYLESS_NODES |
| /* |
| * N.B., Do NOT reference the '_numa_mem_' per cpu variable directly. |
| * It will not be defined when CONFIG_HAVE_MEMORYLESS_NODES is not defined. |
| * Use the accessor functions set_numa_mem(), numa_mem_id() and cpu_to_mem() |
| * defined in <linux/topology.h>. |
| */ |
| DEFINE_PER_CPU(int, _numa_mem_); /* Kernel "local memory" node */ |
| EXPORT_PER_CPU_SYMBOL(_numa_mem_); |
| int _node_numa_mem_[MAX_NUMNODES]; |
| #endif |
| |
| #ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY |
| volatile unsigned long latent_entropy __latent_entropy; |
| EXPORT_SYMBOL(latent_entropy); |
| #endif |
| |
| /* |
| * Array of node states. |
| */ |
| nodemask_t node_states[NR_NODE_STATES] __read_mostly = { |
| [N_POSSIBLE] = NODE_MASK_ALL, |
| [N_ONLINE] = { { [0] = 1UL } }, |
| #ifndef CONFIG_NUMA |
| [N_NORMAL_MEMORY] = { { [0] = 1UL } }, |
| #ifdef CONFIG_HIGHMEM |
| [N_HIGH_MEMORY] = { { [0] = 1UL } }, |
| #endif |
| #ifdef CONFIG_MOVABLE_NODE |
| [N_MEMORY] = { { [0] = 1UL } }, |
| #endif |
| [N_CPU] = { { [0] = 1UL } }, |
| #endif /* NUMA */ |
| }; |
| EXPORT_SYMBOL(node_states); |
| |
| /* Protect totalram_pages and zone->managed_pages */ |
| static DEFINE_SPINLOCK(managed_page_count_lock); |
| |
| unsigned long totalram_pages __read_mostly; |
| unsigned long totalreserve_pages __read_mostly; |
| unsigned long totalcma_pages __read_mostly; |
| |
| int percpu_pagelist_fraction; |
| gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK; |
| |
| /* |
| * A cached value of the page's pageblock's migratetype, used when the page is |
| * put on a pcplist. Used to avoid the pageblock migratetype lookup when |
| * freeing from pcplists in most cases, at the cost of possibly becoming stale. |
| * Also the migratetype set in the page does not necessarily match the pcplist |
| * index, e.g. page might have MIGRATE_CMA set but be on a pcplist with any |
| * other index - this ensures that it will be put on the correct CMA freelist. |
| */ |
| static inline int get_pcppage_migratetype(struct page *page) |
| { |
| return page->index; |
| } |
| |
| static inline void set_pcppage_migratetype(struct page *page, int migratetype) |
| { |
| page->index = migratetype; |
| } |
| |
| #ifdef CONFIG_PM_SLEEP |
| /* |
| * The following functions are used by the suspend/hibernate code to temporarily |
| * change gfp_allowed_mask in order to avoid using I/O during memory allocations |
| * while devices are suspended. To avoid races with the suspend/hibernate code, |
| * they should always be called with pm_mutex held (gfp_allowed_mask also should |
| * only be modified with pm_mutex held, unless the suspend/hibernate code is |
| * guaranteed not to run in parallel with that modification). |
| */ |
| |
| static gfp_t saved_gfp_mask; |
| |
| void pm_restore_gfp_mask(void) |
| { |
| WARN_ON(!mutex_is_locked(&pm_mutex)); |
| if (saved_gfp_mask) { |
| gfp_allowed_mask = saved_gfp_mask; |
| saved_gfp_mask = 0; |
| } |
| } |
| |
| void pm_restrict_gfp_mask(void) |
| { |
| WARN_ON(!mutex_is_locked(&pm_mutex)); |
| WARN_ON(saved_gfp_mask); |
| saved_gfp_mask = gfp_allowed_mask; |
| gfp_allowed_mask &= ~(__GFP_IO | __GFP_FS); |
| } |
| |
| bool pm_suspended_storage(void) |
| { |
| if ((gfp_allowed_mask & (__GFP_IO | __GFP_FS)) == (__GFP_IO | __GFP_FS)) |
| return false; |
| return true; |
| } |
| #endif /* CONFIG_PM_SLEEP */ |
| |
| #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE |
| unsigned int pageblock_order __read_mostly; |
| #endif |
| |
| static void __free_pages_ok(struct page *page, unsigned int order); |
| |
| /* |
| * results with 256, 32 in the lowmem_reserve sysctl: |
| * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high) |
| * 1G machine -> (16M dma, 784M normal, 224M high) |
| * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA |
| * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL |
| * HIGHMEM allocation will leave (224M+784M)/256 of ram reserved in ZONE_DMA |
| * |
| * TBD: should special case ZONE_DMA32 machines here - in those we normally |
| * don't need any ZONE_NORMAL reservation |
| */ |
| int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = { |
| #ifdef CONFIG_ZONE_DMA |
| 256, |
| #endif |
| #ifdef CONFIG_ZONE_DMA32 |
| 256, |
| #endif |
| #ifdef CONFIG_HIGHMEM |
| 32, |
| #endif |
| 32, |
| }; |
| |
| EXPORT_SYMBOL(totalram_pages); |
| |
| static char * const zone_names[MAX_NR_ZONES] = { |
| #ifdef CONFIG_ZONE_DMA |
| "DMA", |
| #endif |
| #ifdef CONFIG_ZONE_DMA32 |
| "DMA32", |
| #endif |
| "Normal", |
| #ifdef CONFIG_HIGHMEM |
| "HighMem", |
| #endif |
| "Movable", |
| #ifdef CONFIG_ZONE_DEVICE |
| "Device", |
| #endif |
| }; |
| |
| char * const migratetype_names[MIGRATE_TYPES] = { |
| "Unmovable", |
| "Movable", |
| "Reclaimable", |
| "HighAtomic", |
| #ifdef CONFIG_CMA |
| "CMA", |
| #endif |
| #ifdef CONFIG_MEMORY_ISOLATION |
| "Isolate", |
| #endif |
| }; |
| |
| compound_page_dtor * const compound_page_dtors[] = { |
| NULL, |
| free_compound_page, |
| #ifdef CONFIG_HUGETLB_PAGE |
| free_huge_page, |
| #endif |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| free_transhuge_page, |
| #endif |
| }; |
| |
| int min_free_kbytes = 1024; |
| int user_min_free_kbytes = -1; |
| int watermark_scale_factor = 10; |
| |
| static unsigned long __meminitdata nr_kernel_pages; |
| static unsigned long __meminitdata nr_all_pages; |
| static unsigned long __meminitdata dma_reserve; |
| |
| #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP |
| static unsigned long __meminitdata arch_zone_lowest_possible_pfn[MAX_NR_ZONES]; |
| static unsigned long __meminitdata arch_zone_highest_possible_pfn[MAX_NR_ZONES]; |
| static unsigned long __initdata required_kernelcore; |
| static unsigned long __initdata required_movablecore; |
| static unsigned long __meminitdata zone_movable_pfn[MAX_NUMNODES]; |
| static bool mirrored_kernelcore; |
| |
| /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */ |
| int movable_zone; |
| EXPORT_SYMBOL(movable_zone); |
| #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ |
| |
| #if MAX_NUMNODES > 1 |
| int nr_node_ids __read_mostly = MAX_NUMNODES; |
| int nr_online_nodes __read_mostly = 1; |
| EXPORT_SYMBOL(nr_node_ids); |
| EXPORT_SYMBOL(nr_online_nodes); |
| #endif |
| |
| int page_group_by_mobility_disabled __read_mostly; |
| |
| #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT |
| static inline void reset_deferred_meminit(pg_data_t *pgdat) |
| { |
| pgdat->first_deferred_pfn = ULONG_MAX; |
| } |
| |
| /* Returns true if the struct page for the pfn is uninitialised */ |
| static inline bool __meminit early_page_uninitialised(unsigned long pfn) |
| { |
| int nid = early_pfn_to_nid(pfn); |
| |
| if (node_online(nid) && pfn >= NODE_DATA(nid)->first_deferred_pfn) |
| return true; |
| |
| return false; |
| } |
| |
| /* |
| * Returns false when the remaining initialisation should be deferred until |
| * later in the boot cycle when it can be parallelised. |
| */ |
| static inline bool update_defer_init(pg_data_t *pgdat, |
| unsigned long pfn, unsigned long zone_end, |
| unsigned long *nr_initialised) |
| { |
| unsigned long max_initialise; |
| |
| /* Always populate low zones for address-contrained allocations */ |
| if (zone_end < pgdat_end_pfn(pgdat)) |
| return true; |
| /* |
| * Initialise at least 2G of a node but also take into account that |
| * two large system hashes that can take up 1GB for 0.25TB/node. |
| */ |
| max_initialise = max(2UL << (30 - PAGE_SHIFT), |
| (pgdat->node_spanned_pages >> 8)); |
| |
| (*nr_initialised)++; |
| if ((*nr_initialised > max_initialise) && |
| (pfn & (PAGES_PER_SECTION - 1)) == 0) { |
| pgdat->first_deferred_pfn = pfn; |
| return false; |
| } |
| |
| return true; |
| } |
| #else |
| static inline void reset_deferred_meminit(pg_data_t *pgdat) |
| { |
| } |
| |
| static inline bool early_page_uninitialised(unsigned long pfn) |
| { |
| return false; |
| } |
| |
| static inline bool update_defer_init(pg_data_t *pgdat, |
| unsigned long pfn, unsigned long zone_end, |
| unsigned long *nr_initialised) |
| { |
| return true; |
| } |
| #endif |
| |
| /* Return a pointer to the bitmap storing bits affecting a block of pages */ |
| static inline unsigned long *get_pageblock_bitmap(struct page *page, |
| unsigned long pfn) |
| { |
| #ifdef CONFIG_SPARSEMEM |
| return __pfn_to_section(pfn)->pageblock_flags; |
| #else |
| return page_zone(page)->pageblock_flags; |
| #endif /* CONFIG_SPARSEMEM */ |
| } |
| |
| static inline int pfn_to_bitidx(struct page *page, unsigned long pfn) |
| { |
| #ifdef CONFIG_SPARSEMEM |
| pfn &= (PAGES_PER_SECTION-1); |
| return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS; |
| #else |
| pfn = pfn - round_down(page_zone(page)->zone_start_pfn, pageblock_nr_pages); |
| return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS; |
| #endif /* CONFIG_SPARSEMEM */ |
| } |
| |
| /** |
| * get_pfnblock_flags_mask - Return the requested group of flags for the pageblock_nr_pages block of pages |
| * @page: The page within the block of interest |
| * @pfn: The target page frame number |
| * @end_bitidx: The last bit of interest to retrieve |
| * @mask: mask of bits that the caller is interested in |
| * |
| * Return: pageblock_bits flags |
| */ |
| static __always_inline unsigned long __get_pfnblock_flags_mask(struct page *page, |
| unsigned long pfn, |
| unsigned long end_bitidx, |
| unsigned long mask) |
| { |
| unsigned long *bitmap; |
| unsigned long bitidx, word_bitidx; |
| unsigned long word; |
| |
| bitmap = get_pageblock_bitmap(page, pfn); |
| bitidx = pfn_to_bitidx(page, pfn); |
| word_bitidx = bitidx / BITS_PER_LONG; |
| bitidx &= (BITS_PER_LONG-1); |
| |
| word = bitmap[word_bitidx]; |
| bitidx += end_bitidx; |
| return (word >> (BITS_PER_LONG - bitidx - 1)) & mask; |
| } |
| |
| unsigned long get_pfnblock_flags_mask(struct page *page, unsigned long pfn, |
| unsigned long end_bitidx, |
| unsigned long mask) |
| { |
| return __get_pfnblock_flags_mask(page, pfn, end_bitidx, mask); |
| } |
| |
| static __always_inline int get_pfnblock_migratetype(struct page *page, unsigned long pfn) |
| { |
| return __get_pfnblock_flags_mask(page, pfn, PB_migrate_end, MIGRATETYPE_MASK); |
| } |
| |
| /** |
| * set_pfnblock_flags_mask - Set the requested group of flags for a pageblock_nr_pages block of pages |
| * @page: The page within the block of interest |
| * @flags: The flags to set |
| * @pfn: The target page frame number |
| * @end_bitidx: The last bit of interest |
| * @mask: mask of bits that the caller is interested in |
| */ |
| void set_pfnblock_flags_mask(struct page *page, unsigned long flags, |
| unsigned long pfn, |
| unsigned long end_bitidx, |
| unsigned long mask) |
| { |
| unsigned long *bitmap; |
| unsigned long bitidx, word_bitidx; |
| unsigned long old_word, word; |
| |
| BUILD_BUG_ON(NR_PAGEBLOCK_BITS != 4); |
| |
| bitmap = get_pageblock_bitmap(page, pfn); |
| bitidx = pfn_to_bitidx(page, pfn); |
| word_bitidx = bitidx / BITS_PER_LONG; |
| bitidx &= (BITS_PER_LONG-1); |
| |
| VM_BUG_ON_PAGE(!zone_spans_pfn(page_zone(page), pfn), page); |
| |
| bitidx += end_bitidx; |
| mask <<= (BITS_PER_LONG - bitidx - 1); |
| flags <<= (BITS_PER_LONG - bitidx - 1); |
| |
| word = READ_ONCE(bitmap[word_bitidx]); |
| for (;;) { |
| old_word = cmpxchg(&bitmap[word_bitidx], word, (word & ~mask) | flags); |
| if (word == old_word) |
| break; |
| word = old_word; |
| } |
| } |
| |
| void set_pageblock_migratetype(struct page *page, int migratetype) |
| { |
| if (unlikely(page_group_by_mobility_disabled && |
| migratetype < MIGRATE_PCPTYPES)) |
| migratetype = MIGRATE_UNMOVABLE; |
| |
| set_pageblock_flags_group(page, (unsigned long)migratetype, |
| PB_migrate, PB_migrate_end); |
| } |
| |
| #ifdef CONFIG_DEBUG_VM |
| static int page_outside_zone_boundaries(struct zone *zone, struct page *page) |
| { |
| int ret = 0; |
| unsigned seq; |
| unsigned long pfn = page_to_pfn(page); |
| unsigned long sp, start_pfn; |
| |
| do { |
| seq = zone_span_seqbegin(zone); |
| start_pfn = zone->zone_start_pfn; |
| sp = zone->spanned_pages; |
| if (!zone_spans_pfn(zone, pfn)) |
| ret = 1; |
| } while (zone_span_seqretry(zone, seq)); |
| |
| if (ret) |
| pr_err("page 0x%lx outside node %d zone %s [ 0x%lx - 0x%lx ]\n", |
| pfn, zone_to_nid(zone), zone->name, |
| start_pfn, start_pfn + sp); |
| |
| return ret; |
| } |
| |
| static int page_is_consistent(struct zone *zone, struct page *page) |
| { |
| if (!pfn_valid_within(page_to_pfn(page))) |
| return 0; |
| if (zone != page_zone(page)) |
| return 0; |
| |
| return 1; |
| } |
| /* |
| * Temporary debugging check for pages not lying within a given zone. |
| */ |
| static int bad_range(struct zone *zone, struct page *page) |
| { |
| if (page_outside_zone_boundaries(zone, page)) |
| return 1; |
| if (!page_is_consistent(zone, page)) |
| return 1; |
| |
| return 0; |
| } |
| #else |
| static inline int bad_range(struct zone *zone, struct page *page) |
| { |
| return 0; |
| } |
| #endif |
| |
| static void bad_page(struct page *page, const char *reason, |
| unsigned long bad_flags) |
| { |
| static unsigned long resume; |
| static unsigned long nr_shown; |
| static unsigned long nr_unshown; |
| |
| /* |
| * Allow a burst of 60 reports, then keep quiet for that minute; |
| * or allow a steady drip of one report per second. |
| */ |
| if (nr_shown == 60) { |
| if (time_before(jiffies, resume)) { |
| nr_unshown++; |
| goto out; |
| } |
| if (nr_unshown) { |
| pr_alert( |
| "BUG: Bad page state: %lu messages suppressed\n", |
| nr_unshown); |
| nr_unshown = 0; |
| } |
| nr_shown = 0; |
| } |
| if (nr_shown++ == 0) |
| resume = jiffies + 60 * HZ; |
| |
| pr_alert("BUG: Bad page state in process %s pfn:%05lx\n", |
| current->comm, page_to_pfn(page)); |
| __dump_page(page, reason); |
| bad_flags &= page->flags; |
| if (bad_flags) |
| pr_alert("bad because of flags: %#lx(%pGp)\n", |
| bad_flags, &bad_flags); |
| dump_page_owner(page); |
| |
| print_modules(); |
| dump_stack(); |
| out: |
| /* Leave bad fields for debug, except PageBuddy could make trouble */ |
| page_mapcount_reset(page); /* remove PageBuddy */ |
| add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); |
| } |
| |
| /* |
| * Higher-order pages are called "compound pages". They are structured thusly: |
| * |
| * The first PAGE_SIZE page is called the "head page" and have PG_head set. |
| * |
| * The remaining PAGE_SIZE pages are called "tail pages". PageTail() is encoded |
| * in bit 0 of page->compound_head. The rest of bits is pointer to head page. |
| * |
| * The first tail page's ->compound_dtor holds the offset in array of compound |
| * page destructors. See compound_page_dtors. |
| * |
| * The first tail page's ->compound_order holds the order of allocation. |
| * This usage means that zero-order pages may not be compound. |
| */ |
| |
| void free_compound_page(struct page *page) |
| { |
| __free_pages_ok(page, compound_order(page)); |
| } |
| |
| void prep_compound_page(struct page *page, unsigned int order) |
| { |
| int i; |
| int nr_pages = 1 << order; |
| |
| set_compound_page_dtor(page, COMPOUND_PAGE_DTOR); |
| set_compound_order(page, order); |
| __SetPageHead(page); |
| for (i = 1; i < nr_pages; i++) { |
| struct page *p = page + i; |
| set_page_count(p, 0); |
| p->mapping = TAIL_MAPPING; |
| set_compound_head(p, page); |
| } |
| atomic_set(compound_mapcount_ptr(page), -1); |
| } |
| |
| #ifdef CONFIG_DEBUG_PAGEALLOC |
| unsigned int _debug_guardpage_minorder; |
| bool _debug_pagealloc_enabled __read_mostly |
| = IS_ENABLED(CONFIG_DEBUG_PAGEALLOC_ENABLE_DEFAULT); |
| EXPORT_SYMBOL(_debug_pagealloc_enabled); |
| bool _debug_guardpage_enabled __read_mostly; |
| |
| static int __init early_debug_pagealloc(char *buf) |
| { |
| if (!buf) |
| return -EINVAL; |
| return kstrtobool(buf, &_debug_pagealloc_enabled); |
| } |
| early_param("debug_pagealloc", early_debug_pagealloc); |
| |
| static bool need_debug_guardpage(void) |
| { |
| /* If we don't use debug_pagealloc, we don't need guard page */ |
| if (!debug_pagealloc_enabled()) |
| return false; |
| |
| if (!debug_guardpage_minorder()) |
| return false; |
| |
| return true; |
| } |
| |
| static void init_debug_guardpage(void) |
| { |
| if (!debug_pagealloc_enabled()) |
| return; |
| |
| if (!debug_guardpage_minorder()) |
| return; |
| |
| _debug_guardpage_enabled = true; |
| } |
| |
| struct page_ext_operations debug_guardpage_ops = { |
| .need = need_debug_guardpage, |
| .init = init_debug_guardpage, |
| }; |
| |
| static int __init debug_guardpage_minorder_setup(char *buf) |
| { |
| unsigned long res; |
| |
| if (kstrtoul(buf, 10, &res) < 0 || res > MAX_ORDER / 2) { |
| pr_err("Bad debug_guardpage_minorder value\n"); |
| return 0; |
| } |
| _debug_guardpage_minorder = res; |
| pr_info("Setting debug_guardpage_minorder to %lu\n", res); |
| return 0; |
| } |
| early_param("debug_guardpage_minorder", debug_guardpage_minorder_setup); |
| |
| static inline bool set_page_guard(struct zone *zone, struct page *page, |
| unsigned int order, int migratetype) |
| { |
| struct page_ext *page_ext; |
| |
| if (!debug_guardpage_enabled()) |
| return false; |
| |
| if (order >= debug_guardpage_minorder()) |
| return false; |
| |
| page_ext = lookup_page_ext(page); |
| if (unlikely(!page_ext)) |
| return false; |
| |
| __set_bit(PAGE_EXT_DEBUG_GUARD, &page_ext->flags); |
| |
| INIT_LIST_HEAD(&page->lru); |
| set_page_private(page, order); |
| /* Guard pages are not available for any usage */ |
| __mod_zone_freepage_state(zone, -(1 << order), migratetype); |
| |
| return true; |
| } |
| |
| static inline void clear_page_guard(struct zone *zone, struct page *page, |
| unsigned int order, int migratetype) |
| { |
| struct page_ext *page_ext; |
| |
| if (!debug_guardpage_enabled()) |
| return; |
| |
| page_ext = lookup_page_ext(page); |
| if (unlikely(!page_ext)) |
| return; |
| |
| __clear_bit(PAGE_EXT_DEBUG_GUARD, &page_ext->flags); |
| |
| set_page_private(page, 0); |
| if (!is_migrate_isolate(migratetype)) |
| __mod_zone_freepage_state(zone, (1 << order), migratetype); |
| } |
| #else |
| struct page_ext_operations debug_guardpage_ops; |
| static inline bool set_page_guard(struct zone *zone, struct page *page, |
| unsigned int order, int migratetype) { return false; } |
| static inline void clear_page_guard(struct zone *zone, struct page *page, |
| unsigned int order, int migratetype) {} |
| #endif |
| |
| static inline void set_page_order(struct page *page, unsigned int order) |
| { |
| set_page_private(page, order); |
| __SetPageBuddy(page); |
| } |
| |
| static inline void rmv_page_order(struct page *page) |
| { |
| __ClearPageBuddy(page); |
| set_page_private(page, 0); |
| } |
| |
| /* |
| * 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 not in a hole && |
| * (b) the buddy is in the buddy system && |
| * (c) a page and its buddy have the same order && |
| * (d) a page and its buddy are in the same zone. |
| * |
| * For recording whether a page is in the buddy system, we set ->_mapcount |
| * PAGE_BUDDY_MAPCOUNT_VALUE. |
| * Setting, clearing, and testing _mapcount PAGE_BUDDY_MAPCOUNT_VALUE is |
| * serialized by zone->lock. |
| * |
| * For recording page's order, we use page_private(page). |
| */ |
| static inline int page_is_buddy(struct page *page, struct page *buddy, |
| unsigned int order) |
| { |
| if (!pfn_valid_within(page_to_pfn(buddy))) |
| return 0; |
| |
| if (page_is_guard(buddy) && page_order(buddy) == order) { |
| if (page_zone_id(page) != page_zone_id(buddy)) |
| return 0; |
| |
| VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy); |
| |
| return 1; |
| } |
| |
| if (PageBuddy(buddy) && page_order(buddy) == order) { |
| /* |
| * zone check is done late to avoid uselessly |
| * calculating zone/node ids for pages that could |
| * never merge. |
| */ |
| if (page_zone_id(page) != page_zone_id(buddy)) |
| return 0; |
| |
| VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy); |
| |
| return 1; |
| } |
| return 0; |
| } |
| |
| /* |
| * Freeing function for a buddy system allocator. |
| * |
| * The concept of a buddy system is to maintain direct-mapped table |
| * (containing bit values) for memory blocks of various "orders". |
| * The bottom level table contains the map for the smallest allocatable |
| * units of memory (here, pages), and each level above it describes |
| * pairs of units from the levels below, hence, "buddies". |
| * At a high level, all that happens here is marking the table entry |
| * at the bottom level available, and propagating the changes upward |
| * as necessary, plus some accounting needed to play nicely with other |
| * parts of the VM system. |
| * At each level, we keep a list of pages, which are heads of continuous |
| * free pages of length of (1 << order) and marked with _mapcount |
| * PAGE_BUDDY_MAPCOUNT_VALUE. Page's order is recorded in page_private(page) |
| * field. |
| * So when we are allocating or freeing one, we can derive the state of the |
| * other. That is, if we allocate a small block, and both were |
| * free, the remainder of the region must be split into blocks. |
| * If a block is freed, and its buddy is also free, then this |
| * triggers coalescing into a block of larger size. |
| * |
| * -- nyc |
| */ |
| |
| static inline void __free_one_page(struct page *page, |
| unsigned long pfn, |
| struct zone *zone, unsigned int order, |
| int migratetype) |
| { |
| unsigned long page_idx; |
| unsigned long combined_idx; |
| unsigned long uninitialized_var(buddy_idx); |
| struct page *buddy; |
| unsigned int max_order; |
| |
| max_order = min_t(unsigned int, MAX_ORDER, pageblock_order + 1); |
| |
| VM_BUG_ON(!zone_is_initialized(zone)); |
| VM_BUG_ON_PAGE(page->flags & PAGE_FLAGS_CHECK_AT_PREP, page); |
| |
| VM_BUG_ON(migratetype == -1); |
| if (likely(!is_migrate_isolate(migratetype))) |
| __mod_zone_freepage_state(zone, 1 << order, migratetype); |
| |
| page_idx = pfn & ((1 << MAX_ORDER) - 1); |
| |
| VM_BUG_ON_PAGE(page_idx & ((1 << order) - 1), page); |
| VM_BUG_ON_PAGE(bad_range(zone, page), page); |
| |
| continue_merging: |
| while (order < max_order - 1) { |
| buddy_idx = __find_buddy_index(page_idx, order); |
| buddy = page + (buddy_idx - page_idx); |
| if (!page_is_buddy(page, buddy, order)) |
| goto done_merging; |
| /* |
| * Our buddy is free or it is CONFIG_DEBUG_PAGEALLOC guard page, |
| * merge with it and move up one order. |
| */ |
| if (page_is_guard(buddy)) { |
| clear_page_guard(zone, buddy, order, migratetype); |
| } else { |
| list_del(&buddy->lru); |
| zone->free_area[order].nr_free--; |
| rmv_page_order(buddy); |
| } |
| combined_idx = buddy_idx & page_idx; |
| page = page + (combined_idx - page_idx); |
| page_idx = combined_idx; |
| order++; |
| } |
| if (max_order < MAX_ORDER) { |
| /* If we are here, it means order is >= pageblock_order. |
| * We want to prevent merge between freepages on isolate |
| * pageblock and normal pageblock. Without this, pageblock |
| * isolation could cause incorrect freepage or CMA accounting. |
| * |
| * We don't want to hit this code for the more frequent |
| * low-order merging. |
| */ |
| if (unlikely(has_isolate_pageblock(zone))) { |
| int buddy_mt; |
| |
| buddy_idx = __find_buddy_index(page_idx, order); |
| buddy = page + (buddy_idx - page_idx); |
| buddy_mt = get_pageblock_migratetype(buddy); |
| |
| if (migratetype != buddy_mt |
| && (is_migrate_isolate(migratetype) || |
| is_migrate_isolate(buddy_mt))) |
| goto done_merging; |
| } |
| max_order++; |
| goto continue_merging; |
| } |
| |
| done_merging: |
| set_page_order(page, order); |
| |
| /* |
| * If this is not the largest possible page, check if the buddy |
| * of the next-highest order is free. If it is, it's possible |
| * that pages are being freed that will coalesce soon. In case, |
| * that is happening, add the free page to the tail of the list |
| * so it's less likely to be used soon and more likely to be merged |
| * as a higher order page |
| */ |
| if ((order < MAX_ORDER-2) && pfn_valid_within(page_to_pfn(buddy))) { |
| struct page *higher_page, *higher_buddy; |
| combined_idx = buddy_idx & page_idx; |
| higher_page = page + (combined_idx - page_idx); |
| buddy_idx = __find_buddy_index(combined_idx, order + 1); |
| higher_buddy = higher_page + (buddy_idx - combined_idx); |
| if (page_is_buddy(higher_page, higher_buddy, order + 1)) { |
| list_add_tail(&page->lru, |
| &zone->free_area[order].free_list[migratetype]); |
| goto out; |
| } |
| } |
| |
| list_add(&page->lru, &zone->free_area[order].free_list[migratetype]); |
| out: |
| zone->free_area[order].nr_free++; |
| } |
| |
| /* |
| * A bad page could be due to a number of fields. Instead of multiple branches, |
| * try and check multiple fields with one check. The caller must do a detailed |
| * check if necessary. |
| */ |
| static inline bool page_expected_state(struct page *page, |
| unsigned long check_flags) |
| { |
| if (unlikely(atomic_read(&page->_mapcount) != -1)) |
| return false; |
| |
| if (unlikely((unsigned long)page->mapping | |
| page_ref_count(page) | |
| #ifdef CONFIG_MEMCG |
| (unsigned long)page->mem_cgroup | |
| #endif |
| (page->flags & check_flags))) |
| return false; |
| |
| return true; |
| } |
| |
| static void free_pages_check_bad(struct page *page) |
| { |
| const char *bad_reason; |
| unsigned long bad_flags; |
| |
| bad_reason = NULL; |
| bad_flags = 0; |
| |
| if (unlikely(atomic_read(&page->_mapcount) != -1)) |
| bad_reason = "nonzero mapcount"; |
| if (unlikely(page->mapping != NULL)) |
| bad_reason = "non-NULL mapping"; |
| if (unlikely(page_ref_count(page) != 0)) |
| bad_reason = "nonzero _refcount"; |
| if (unlikely(page->flags & PAGE_FLAGS_CHECK_AT_FREE)) { |
| bad_reason = "PAGE_FLAGS_CHECK_AT_FREE flag(s) set"; |
| bad_flags = PAGE_FLAGS_CHECK_AT_FREE; |
| } |
| #ifdef CONFIG_MEMCG |
| if (unlikely(page->mem_cgroup)) |
| bad_reason = "page still charged to cgroup"; |
| #endif |
| bad_page(page, bad_reason, bad_flags); |
| } |
| |
| static inline int free_pages_check(struct page *page) |
| { |
| if (likely(page_expected_state(page, PAGE_FLAGS_CHECK_AT_FREE))) |
| return 0; |
| |
| /* Something has gone sideways, find it */ |
| free_pages_check_bad(page); |
| return 1; |
| } |
| |
| static int free_tail_pages_check(struct page *head_page, struct page *page) |
| { |
| int ret = 1; |
| |
| /* |
| * We rely page->lru.next never has bit 0 set, unless the page |
| * is PageTail(). Let's make sure that's true even for poisoned ->lru. |
| */ |
| BUILD_BUG_ON((unsigned long)LIST_POISON1 & 1); |
| |
| if (!IS_ENABLED(CONFIG_DEBUG_VM)) { |
| ret = 0; |
| goto out; |
| } |
| switch (page - head_page) { |
| case 1: |
| /* the first tail page: ->mapping is compound_mapcount() */ |
| if (unlikely(compound_mapcount(page))) { |
| bad_page(page, "nonzero compound_mapcount", 0); |
| goto out; |
| } |
| break; |
| case 2: |
| /* |
| * the second tail page: ->mapping is |
| * page_deferred_list().next -- ignore value. |
| */ |
| break; |
| default: |
| if (page->mapping != TAIL_MAPPING) { |
| bad_page(page, "corrupted mapping in tail page", 0); |
| goto out; |
| } |
| break; |
| } |
| if (unlikely(!PageTail(page))) { |
| bad_page(page, "PageTail not set", 0); |
| goto out; |
| } |
| if (unlikely(compound_head(page) != head_page)) { |
| bad_page(page, "compound_head not consistent", 0); |
| goto out; |
| } |
| ret = 0; |
| out: |
| page->mapping = NULL; |
| clear_compound_head(page); |
| return ret; |
| } |
| |
| static __always_inline bool free_pages_prepare(struct page *page, |
| unsigned int order, bool check_free) |
| { |
| int bad = 0; |
| |
| VM_BUG_ON_PAGE(PageTail(page), page); |
| |
| trace_mm_page_free(page, order); |
| kmemcheck_free_shadow(page, order); |
| |
| /* |
| * Check tail pages before head page information is cleared to |
| * avoid checking PageCompound for order-0 pages. |
| */ |
| if (unlikely(order)) { |
| bool compound = PageCompound(page); |
| int i; |
| |
| VM_BUG_ON_PAGE(compound && compound_order(page) != order, page); |
| |
| if (compound) |
| ClearPageDoubleMap(page); |
| for (i = 1; i < (1 << order); i++) { |
| if (compound) |
| bad += free_tail_pages_check(page, page + i); |
| if (unlikely(free_pages_check(page + i))) { |
| bad++; |
| continue; |
| } |
| (page + i)->flags &= ~PAGE_FLAGS_CHECK_AT_PREP; |
| } |
| } |
| if (PageMappingFlags(page)) |
| page->mapping = NULL; |
| if (memcg_kmem_enabled() && PageKmemcg(page)) |
| memcg_kmem_uncharge(page, order); |
| if (check_free) |
| bad += free_pages_check(page); |
| if (bad) |
| return false; |
| |
| page_cpupid_reset_last(page); |
| page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP; |
| reset_page_owner(page, order); |
| |
| if (!PageHighMem(page)) { |
| debug_check_no_locks_freed(page_address(page), |
| PAGE_SIZE << order); |
| debug_check_no_obj_freed(page_address(page), |
| PAGE_SIZE << order); |
| } |
| arch_free_page(page, order); |
| kernel_poison_pages(page, 1 << order, 0); |
| kernel_map_pages(page, 1 << order, 0); |
| kasan_free_pages(page, order); |
| |
| return true; |
| } |
| |
| #ifdef CONFIG_DEBUG_VM |
| static inline bool free_pcp_prepare(struct page *page) |
| { |
| return free_pages_prepare(page, 0, true); |
| } |
| |
| static inline bool bulkfree_pcp_prepare(struct page *page) |
| { |
| return false; |
| } |
| #else |
| static bool free_pcp_prepare(struct page *page) |
| { |
| return free_pages_prepare(page, 0, false); |
| } |
| |
| static bool bulkfree_pcp_prepare(struct page *page) |
| { |
| return free_pages_check(page); |
| } |
| #endif /* CONFIG_DEBUG_VM */ |
| |
| /* |
| * Frees a number of pages from the PCP lists |
| * Assumes all pages on list are in same zone, and of same order. |
| * count is the number of pages to free. |
| * |
| * If the zone was previously in an "all pages pinned" state then look to |
| * see if this freeing clears that state. |
| * |
| * And clear the zone's pages_scanned counter, to hold off the "all pages are |
| * pinned" detection logic. |
| */ |
| static void free_pcppages_bulk(struct zone *zone, int count, |
| struct per_cpu_pages *pcp) |
| { |
| int migratetype = 0; |
| int batch_free = 0; |
| unsigned long nr_scanned; |
| bool isolated_pageblocks; |
| |
| spin_lock(&zone->lock); |
| isolated_pageblocks = has_isolate_pageblock(zone); |
| nr_scanned = node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED); |
| if (nr_scanned) |
| __mod_node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED, -nr_scanned); |
| |
| while (count) { |
| struct page *page; |
| struct list_head *list; |
| |
| /* |
| * Remove pages from lists in a round-robin fashion. A |
| * batch_free count is maintained that is incremented when an |
| * empty list is encountered. This is so more pages are freed |
| * off fuller lists instead of spinning excessively around empty |
| * lists |
| */ |
| do { |
| batch_free++; |
| if (++migratetype == MIGRATE_PCPTYPES) |
| migratetype = 0; |
| list = &pcp->lists[migratetype]; |
| } while (list_empty(list)); |
| |
| /* This is the only non-empty list. Free them all. */ |
| if (batch_free == MIGRATE_PCPTYPES) |
| batch_free = count; |
| |
| do { |
| int mt; /* migratetype of the to-be-freed page */ |
| |
| page = list_last_entry(list, struct page, lru); |
| /* must delete as __free_one_page list manipulates */ |
| list_del(&page->lru); |
| |
| mt = get_pcppage_migratetype(page); |
| /* MIGRATE_ISOLATE page should not go to pcplists */ |
| VM_BUG_ON_PAGE(is_migrate_isolate(mt), page); |
| /* Pageblock could have been isolated meanwhile */ |
| if (unlikely(isolated_pageblocks)) |
| mt = get_pageblock_migratetype(page); |
| |
| if (bulkfree_pcp_prepare(page)) |
| continue; |
| |
| __free_one_page(page, page_to_pfn(page), zone, 0, mt); |
| trace_mm_page_pcpu_drain(page, 0, mt); |
| } while (--count && --batch_free && !list_empty(list)); |
| } |
| spin_unlock(&zone->lock); |
| } |
| |
| static void free_one_page(struct zone *zone, |
| struct page *page, unsigned long pfn, |
| unsigned int order, |
| int migratetype) |
| { |
| unsigned long nr_scanned; |
| spin_lock(&zone->lock); |
| nr_scanned = node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED); |
| if (nr_scanned) |
| __mod_node_page_state(zone->zone_pgdat, NR_PAGES_SCANNED, -nr_scanned); |
| |
| if (unlikely(has_isolate_pageblock(zone) || |
| is_migrate_isolate(migratetype))) { |
| migratetype = get_pfnblock_migratetype(page, pfn); |
| } |
| __free_one_page(page, pfn, zone, order, migratetype); |
| spin_unlock(&zone->lock); |
| } |
| |
| static void __meminit __init_single_page(struct page *page, unsigned long pfn, |
| unsigned long zone, int nid) |
| { |
| set_page_links(page, zone, nid, pfn); |
| init_page_count(page); |
| page_mapcount_reset(page); |
| page_cpupid_reset_last(page); |
| |
| INIT_LIST_HEAD(&page->lru); |
| #ifdef WANT_PAGE_VIRTUAL |
| /* The shift won't overflow because ZONE_NORMAL is below 4G. */ |
| if (!is_highmem_idx(zone)) |
| set_page_address(page, __va(pfn << PAGE_SHIFT)); |
| #endif |
| } |
| |
| static void __meminit __init_single_pfn(unsigned long pfn, unsigned long zone, |
| int nid) |
| { |
| return __init_single_page(pfn_to_page(pfn), pfn, zone, nid); |
| } |
| |
| #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT |
| static void init_reserved_page(unsigned long pfn) |
| { |
| pg_data_t *pgdat; |
| int nid, zid; |
| |
| if (!early_page_uninitialised(pfn)) |
| return; |
| |
| nid = early_pfn_to_nid(pfn); |
| pgdat = NODE_DATA(nid); |
| |
| for (zid = 0; zid < MAX_NR_ZONES; zid++) { |
| struct zone *zone = &pgdat->node_zones[zid]; |
| |
| if (pfn >= zone->zone_start_pfn && pfn < zone_end_pfn(zone)) |
| break; |
| } |
| __init_single_pfn(pfn, zid, nid); |
| } |
| #else |
| static inline void init_reserved_page(unsigned long pfn) |
| { |
| } |
| #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ |
| |
| /* |
| * Initialised pages do not have PageReserved set. This function is |
| * called for each range allocated by the bootmem allocator and |
| * marks the pages PageReserved. The remaining valid pages are later |
| * sent to the buddy page allocator. |
| */ |
| void __meminit reserve_bootmem_region(phys_addr_t start, phys_addr_t end) |
| { |
| unsigned long start_pfn = PFN_DOWN(start); |
| unsigned long end_pfn = PFN_UP(end); |
| |
| for (; start_pfn < end_pfn; start_pfn++) { |
| if (pfn_valid(start_pfn)) { |
| struct page *page = pfn_to_page(start_pfn); |
| |
| init_reserved_page(start_pfn); |
| |
| /* Avoid false-positive PageTail() */ |
| INIT_LIST_HEAD(&page->lru); |
| |
| SetPageReserved(page); |
| } |
| } |
| } |
| |
| static void __free_pages_ok(struct page *page, unsigned int order) |
| { |
| unsigned long flags; |
| int migratetype; |
| unsigned long pfn = page_to_pfn(page); |
| |
| if (!free_pages_prepare(page, order, true)) |
| return; |
| |
| migratetype = get_pfnblock_migratetype(page, pfn); |
| local_irq_save(flags); |
| __count_vm_events(PGFREE, 1 << order); |
| free_one_page(page_zone(page), page, pfn, order, migratetype); |
| local_irq_restore(flags); |
| } |
| |
| static void __init __free_pages_boot_core(struct page *page, unsigned int order) |
| { |
| unsigned int nr_pages = 1 << order; |
| struct page *p = page; |
| unsigned int loop; |
| |
| prefetchw(p); |
| for (loop = 0; loop < (nr_pages - 1); loop++, p++) { |
| prefetchw(p + 1); |
| __ClearPageReserved(p); |
| set_page_count(p, 0); |
| } |
| __ClearPageReserved(p); |
| set_page_count(p, 0); |
| |
| page_zone(page)->managed_pages += nr_pages; |
| set_page_refcounted(page); |
| __free_pages(page, order); |
| } |
| |
| #if defined(CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID) || \ |
| defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) |
| |
| static struct mminit_pfnnid_cache early_pfnnid_cache __meminitdata; |
| |
| int __meminit early_pfn_to_nid(unsigned long pfn) |
| { |
| static DEFINE_SPINLOCK(early_pfn_lock); |
| int nid; |
| |
| spin_lock(&early_pfn_lock); |
| nid = __early_pfn_to_nid(pfn, &early_pfnnid_cache); |
| if (nid < 0) |
| nid = first_online_node; |
| spin_unlock(&early_pfn_lock); |
| |
| return nid; |
| } |
| #endif |
| |
| #ifdef CONFIG_NODES_SPAN_OTHER_NODES |
| static inline bool __meminit meminit_pfn_in_nid(unsigned long pfn, int node, |
| struct mminit_pfnnid_cache *state) |
| { |
| int nid; |
| |
| nid = __early_pfn_to_nid(pfn, state); |
| if (nid >= 0 && nid != node) |
| return false; |
| return true; |
| } |
| |
| /* Only safe to use early in boot when initialisation is single-threaded */ |
| static inline bool __meminit early_pfn_in_nid(unsigned long pfn, int node) |
| { |
| return meminit_pfn_in_nid(pfn, node, &early_pfnnid_cache); |
| } |
| |
| #else |
| |
| static inline bool __meminit early_pfn_in_nid(unsigned long pfn, int node) |
| { |
| return true; |
| } |
| static inline bool __meminit meminit_pfn_in_nid(unsigned long pfn, int node, |
| struct mminit_pfnnid_cache *state) |
| { |
| return true; |
| } |
| #endif |
| |
| |
| void __init __free_pages_bootmem(struct page *page, unsigned long pfn, |
| unsigned int order) |
| { |
| if (early_page_uninitialised(pfn)) |
| return; |
| return __free_pages_boot_core(page, order); |
| } |
| |
| /* |
| * Check that the whole (or subset of) a pageblock given by the interval of |
| * [start_pfn, end_pfn) is valid and within the same zone, before scanning it |
| * with the migration of free compaction scanner. The scanners then need to |
| * use only pfn_valid_within() check for arches that allow holes within |
| * pageblocks. |
| * |
| * Return struct page pointer of start_pfn, or NULL if checks were not passed. |
| * |
| * It's possible on some configurations to have a setup like node0 node1 node0 |
| * i.e. it's possible that all pages within a zones range of pages do not |
| * belong to a single zone. We assume that a border between node0 and node1 |
| * can occur within a single pageblock, but not a node0 node1 node0 |
| * interleaving within a single pageblock. It is therefore sufficient to check |
| * the first and last page of a pageblock and avoid checking each individual |
| * page in a pageblock. |
| */ |
| struct page *__pageblock_pfn_to_page(unsigned long start_pfn, |
| unsigned long end_pfn, struct zone *zone) |
| { |
| struct page *start_page; |
| struct page *end_page; |
| |
| /* end_pfn is one past the range we are checking */ |
| end_pfn--; |
| |
| if (!pfn_valid(start_pfn) || !pfn_valid(end_pfn)) |
| return NULL; |
| |
| start_page = pfn_to_page(start_pfn); |
| |
| if (page_zone(start_page) != zone) |
| return NULL; |
| |
| end_page = pfn_to_page(end_pfn); |
| |
| /* This gives a shorter code than deriving page_zone(end_page) */ |
| if (page_zone_id(start_page) != page_zone_id(end_page)) |
| return NULL; |
| |
| return start_page; |
| } |
| |
| void set_zone_contiguous(struct zone *zone) |
| { |
| unsigned long block_start_pfn = zone->zone_start_pfn; |
| unsigned long block_end_pfn; |
| |
| block_end_pfn = ALIGN(block_start_pfn + 1, pageblock_nr_pages); |
| for (; block_start_pfn < zone_end_pfn(zone); |
| block_start_pfn = block_end_pfn, |
| block_end_pfn += pageblock_nr_pages) { |
| |
| block_end_pfn = min(block_end_pfn, zone_end_pfn(zone)); |
| |
| if (!__pageblock_pfn_to_page(block_start_pfn, |
| block_end_pfn, zone)) |
| return; |
| } |
| |
| /* We confirm that there is no hole */ |
| zone->contiguous = true; |
| } |
| |
| void clear_zone_contiguous(struct zone *zone) |
| { |
| zone->contiguous = false; |
| } |
| |
| #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT |
| static void __init deferred_free_range(struct page *page, |
| unsigned long pfn, int nr_pages) |
| { |
| int i; |
| |
| if (!page) |
| return; |
| |
| /* Free a large naturally-aligned chunk if possible */ |
| if (nr_pages == pageblock_nr_pages && |
| (pfn & (pageblock_nr_pages - 1)) == 0) { |
| set_pageblock_migratetype(page, MIGRATE_MOVABLE); |
| __free_pages_boot_core(page, pageblock_order); |
| return; |
| } |
| |
| for (i = 0; i < nr_pages; i++, page++, pfn++) { |
| if ((pfn & (pageblock_nr_pages - 1)) == 0) |
| set_pageblock_migratetype(page, MIGRATE_MOVABLE); |
| __free_pages_boot_core(page, 0); |
| } |
| } |
| |
| /* Completion tracking for deferred_init_memmap() threads */ |
| static atomic_t pgdat_init_n_undone __initdata; |
| static __initdata DECLARE_COMPLETION(pgdat_init_all_done_comp); |
| |
| static inline void __init pgdat_init_report_one_done(void) |
| { |
| if (atomic_dec_and_test(&pgdat_init_n_undone)) |
| complete(&pgdat_init_all_done_comp); |
| } |
| |
| /* Initialise remaining memory on a node */ |
| static int __init deferred_init_memmap(void *data) |
| { |
| pg_data_t *pgdat = data; |
| int nid = pgdat->node_id; |
| struct mminit_pfnnid_cache nid_init_state = { }; |
| unsigned long start = jiffies; |
| unsigned long nr_pages = 0; |
| unsigned long walk_start, walk_end; |
| int i, zid; |
| struct zone *zone; |
| unsigned long first_init_pfn = pgdat->first_deferred_pfn; |
| const struct cpumask *cpumask = cpumask_of_node(pgdat->node_id); |
| |
| if (first_init_pfn == ULONG_MAX) { |
| pgdat_init_report_one_done(); |
| return 0; |
| } |
| |
| /* Bind memory initialisation thread to a local node if possible */ |
| if (!cpumask_empty(cpumask)) |
| set_cpus_allowed_ptr(current, cpumask); |
| |
| /* Sanity check boundaries */ |
| BUG_ON(pgdat->first_deferred_pfn < pgdat->node_start_pfn); |
| BUG_ON(pgdat->first_deferred_pfn > pgdat_end_pfn(pgdat)); |
| pgdat->first_deferred_pfn = ULONG_MAX; |
| |
| /* Only the highest zone is deferred so find it */ |
| for (zid = 0; zid < MAX_NR_ZONES; zid++) { |
| zone = pgdat->node_zones + zid; |
| if (first_init_pfn < zone_end_pfn(zone)) |
| break; |
| } |
| |
| for_each_mem_pfn_range(i, nid, &walk_start, &walk_end, NULL) { |
| unsigned long pfn, end_pfn; |
| struct page *page = NULL; |
| struct page *free_base_page = NULL; |
| unsigned long free_base_pfn = 0; |
| int nr_to_free = 0; |
| |
| end_pfn = min(walk_end, zone_end_pfn(zone)); |
| pfn = first_init_pfn; |
| if (pfn < walk_start) |
| pfn = walk_start; |
| if (pfn < zone->zone_start_pfn) |
| pfn = zone->zone_start_pfn; |
| |
| for (; pfn < end_pfn; pfn++) { |
| if (!pfn_valid_within(pfn)) |
| goto free_range; |
| |
| /* |
| * Ensure pfn_valid is checked every |
| * pageblock_nr_pages for memory holes |
| */ |
| if ((pfn & (pageblock_nr_pages - 1)) == 0) { |
| if (!pfn_valid(pfn)) { |
| page = NULL; |
| goto free_range; |
| } |
| } |
| |
| if (!meminit_pfn_in_nid(pfn, nid, &nid_init_state)) { |
| page = NULL; |
| goto free_range; |
| } |
| |
| /* Minimise pfn page lookups and scheduler checks */ |
| if (page && (pfn & (pageblock_nr_pages - 1)) != 0) { |
| page++; |
| } else { |
| nr_pages += nr_to_free; |
| deferred_free_range(free_base_page, |
| free_base_pfn, nr_to_free); |
| free_base_page = NULL; |
| free_base_pfn = nr_to_free = 0; |
| |
| page = pfn_to_page(pfn); |
| cond_resched(); |
| } |
| |
| if (page->flags) { |
| VM_BUG_ON(page_zone(page) != zone); |
| goto free_range; |
| } |
| |
| __init_single_page(page, pfn, zid, nid); |
| if (!free_base_page) { |
| free_base_page = page; |
| free_base_pfn = pfn; |
| nr_to_free = 0; |
| } |
| nr_to_free++; |
| |
| /* Where possible, batch up pages for a single free */ |
| continue; |
| free_range: |
| /* Free the current block of pages to allocator */ |
| nr_pages += nr_to_free; |
| deferred_free_range(free_base_page, free_base_pfn, |
| nr_to_free); |
| free_base_page = NULL; |
| free_base_pfn = nr_to_free = 0; |
| } |
| /* Free the last block of pages to allocator */ |
| nr_pages += nr_to_free; |
| deferred_free_range(free_base_page, free_base_pfn, nr_to_free); |
| |
| first_init_pfn = max(end_pfn, first_init_pfn); |
| } |
| |
| /* Sanity check that the next zone really is unpopulated */ |
| WARN_ON(++zid < MAX_NR_ZONES && populated_zone(++zone)); |
| |
| pr_info("node %d initialised, %lu pages in %ums\n", nid, nr_pages, |
| jiffies_to_msecs(jiffies - start)); |
| |
| pgdat_init_report_one_done(); |
| return 0; |
| } |
| #endif /* CONFIG_DEFERRED_STRUCT_PAGE_INIT */ |
| |
| void __init page_alloc_init_late(void) |
| { |
| struct zone *zone; |
| |
| #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT |
| int nid; |
| |
| /* There will be num_node_state(N_MEMORY) threads */ |
| atomic_set(&pgdat_init_n_undone, num_node_state(N_MEMORY)); |
| for_each_node_state(nid, N_MEMORY) { |
| kthread_run(deferred_init_memmap, NODE_DATA(nid), "pgdatinit%d", nid); |
| } |
| |
| /* Block until all are initialised */ |
| wait_for_completion(&pgdat_init_all_done_comp); |
| |
| /* Reinit limits that are based on free pages after the kernel is up */ |
| files_maxfiles_init(); |
| #endif |
| |
| for_each_populated_zone(zone) |
| set_zone_contiguous(zone); |
| } |
| |
| #ifdef CONFIG_CMA |
| /* Free whole pageblock and set its migration type to MIGRATE_CMA. */ |
| void __init init_cma_reserved_pageblock(struct page *page) |
| { |
| unsigned i = pageblock_nr_pages; |
| struct page *p = page; |
| |
| do { |
| __ClearPageReserved(p); |
| set_page_count(p, 0); |
| } while (++p, --i); |
| |
| set_pageblock_migratetype(page, MIGRATE_CMA); |
| |
| if (pageblock_order >= MAX_ORDER) { |
| i = pageblock_nr_pages; |
| p = page; |
| do { |
| set_page_refcounted(p); |
| __free_pages(p, MAX_ORDER - 1); |
| p += MAX_ORDER_NR_PAGES; |
| } while (i -= MAX_ORDER_NR_PAGES); |
| } else { |
| set_page_refcounted(page); |
| __free_pages(page, pageblock_order); |
| } |
| |
| adjust_managed_page_count(page, pageblock_nr_pages); |
| } |
| #endif |
| |
| /* |
| * The order of subdivision here is critical for the IO subsystem. |
| * Please do not alter this order without good reasons and regression |
| * testing. Specifically, as large blocks of memory are subdivided, |
| * the order in which smaller blocks are delivered depends on the order |
| * they're subdivided in this function. This is the primary factor |
| * influencing the order in which pages are delivered to the IO |
| * subsystem according to empirical testing, and this is also justified |
| * by considering the behavior of a buddy system containing a single |
| * large block of memory acted on by a series of small allocations. |
| * This behavior is a critical factor in sglist merging's success. |
| * |
| * -- nyc |
| */ |
| static inline void expand(struct zone *zone, struct page *page, |
| int low, int high, struct free_area *area, |
| int migratetype) |
| { |
| unsigned long size = 1 << high; |
| |
| while (high > low) { |
| area--; |
| high--; |
| size >>= 1; |
| VM_BUG_ON_PAGE(bad_range(zone, &page[size]), &page[size]); |
| |
| /* |
| * Mark as guard pages (or page), that will allow to |
| * merge back to allocator when buddy will be freed. |
| * Corresponding page table entries will not be touched, |
| * pages will stay not present in virtual address space |
| */ |
| if (set_page_guard(zone, &page[size], high, migratetype)) |
| continue; |
| |
| list_add(&page[size].lru, &area->free_list[migratetype]); |
| area->nr_free++; |
| set_page_order(&page[size], high); |
| } |
| } |
| |
| static void check_new_page_bad(struct page *page) |
| { |
| const char *bad_reason = NULL; |
| unsigned long bad_flags = 0; |
| |
| if (unlikely(atomic_read(&page->_mapcount) != -1)) |
| bad_reason = "nonzero mapcount"; |
| if (unlikely(page->mapping != NULL)) |
| bad_reason = "non-NULL mapping"; |
| if (unlikely(page_ref_count(page) != 0)) |
| bad_reason = "nonzero _count"; |
| if (unlikely(page->flags & __PG_HWPOISON)) { |
| bad_reason = "HWPoisoned (hardware-corrupted)"; |
| bad_flags = __PG_HWPOISON; |
| /* Don't complain about hwpoisoned pages */ |
| page_mapcount_reset(page); /* remove PageBuddy */ |
| return; |
| } |
| if (unlikely(page->flags & PAGE_FLAGS_CHECK_AT_PREP)) { |
| bad_reason = "PAGE_FLAGS_CHECK_AT_PREP flag set"; |
| bad_flags = PAGE_FLAGS_CHECK_AT_PREP; |
| } |
| #ifdef CONFIG_MEMCG |
| if (unlikely(page->mem_cgroup)) |
| bad_reason = "page still charged to cgroup"; |
| #endif |
| bad_page(page, bad_reason, bad_flags); |
| } |
| |
| /* |
| * This page is about to be returned from the page allocator |
| */ |
| static inline int check_new_page(struct page *page) |
| { |
| if (likely(page_expected_state(page, |
| PAGE_FLAGS_CHECK_AT_PREP|__PG_HWPOISON))) |
| return 0; |
| |
| check_new_page_bad(page); |
| return 1; |
| } |
| |
| static inline bool free_pages_prezeroed(bool poisoned) |
| { |
| return IS_ENABLED(CONFIG_PAGE_POISONING_ZERO) && |
| page_poisoning_enabled() && poisoned; |
| } |
| |
| #ifdef CONFIG_DEBUG_VM |
| static bool check_pcp_refill(struct page *page) |
| { |
| return false; |
| } |
| |
| static bool check_new_pcp(struct page *page) |
| { |
| return check_new_page(page); |
| } |
| #else |
| static bool check_pcp_refill(struct page *page) |
| { |
| return check_new_page(page); |
| } |
| static bool check_new_pcp(struct page *page) |
| { |
| return false; |
| } |
| #endif /* CONFIG_DEBUG_VM */ |
| |
| static bool check_new_pages(struct page *page, unsigned int order) |
| { |
| int i; |
| for (i = 0; i < (1 << order); i++) { |
| struct page *p = page + i; |
| |
| if (unlikely(check_new_page(p))) |
| return true; |
| } |
| |
| return false; |
| } |
| |
| inline void post_alloc_hook(struct page *page, unsigned int order, |
| gfp_t gfp_flags) |
| { |
| set_page_private(page, 0); |
| set_page_refcounted(page); |
| |
| arch_alloc_page(page, order); |
| kernel_map_pages(page, 1 << order, 1); |
| kernel_poison_pages(page, 1 << order, 1); |
| kasan_alloc_pages(page, order); |
| set_page_owner(page, order, gfp_flags); |
| } |
| |
| static void prep_new_page(struct page *page, unsigned int order, gfp_t gfp_flags, |
| unsigned int alloc_flags) |
| { |
| int i; |
| bool poisoned = true; |
| |
| for (i = 0; i < (1 << order); i++) { |
| struct page *p = page + i; |
| if (poisoned) |
| poisoned &= page_is_poisoned(p); |
| } |
| |
| post_alloc_hook(page, order, gfp_flags); |
| |
| if (!free_pages_prezeroed(poisoned) && (gfp_flags & __GFP_ZERO)) |
| for (i = 0; i < (1 << order); i++) |
| clear_highpage(page + i); |
| |
| if (order && (gfp_flags & __GFP_COMP)) |
| prep_compound_page(page, order); |
| |
| /* |
| * page is set pfmemalloc when ALLOC_NO_WATERMARKS was necessary to |
| * allocate the page. The expectation is that the caller is taking |
| * steps that will free more memory. The caller should avoid the page |
| * being used for !PFMEMALLOC purposes. |
| */ |
| if (alloc_flags & ALLOC_NO_WATERMARKS) |
| set_page_pfmemalloc(page); |
| else |
| clear_page_pfmemalloc(page); |
| } |
| |
| /* |
| * Go through the free lists for the given migratetype and remove |
| * the smallest available page from the freelists |
| */ |
| static inline |
| struct page *__rmqueue_smallest(struct zone *zone, unsigned int order, |
| int migratetype) |
| { |
| unsigned int current_order; |
| struct free_area *area; |
| struct page *page; |
| |
| /* Find a page of the appropriate size in the preferred list */ |
| for (current_order = order; current_order < MAX_ORDER; ++current_order) { |
| area = &(zone->free_area[current_order]); |
| page = list_first_entry_or_null(&area->free_list[migratetype], |
| struct page, lru); |
| if (!page) |
| continue; |
| list_del(&page->lru); |
| rmv_page_order(page); |
| area->nr_free--; |
| expand(zone, page, order, current_order, area, migratetype); |
| set_pcppage_migratetype(page, migratetype); |
| return page; |
| } |
| |
| return NULL; |
| } |
| |
| |
| /* |
| * This array describes the order lists are fallen back to when |
| * the free lists for the desirable migrate type are depleted |
| */ |
| static int fallbacks[MIGRATE_TYPES][4] = { |
| [MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_TYPES }, |
| [MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_TYPES }, |
| [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_TYPES }, |
| #ifdef CONFIG_CMA |
| [MIGRATE_CMA] = { MIGRATE_TYPES }, /* Never used */ |
| #endif |
| #ifdef CONFIG_MEMORY_ISOLATION |
| [MIGRATE_ISOLATE] = { MIGRATE_TYPES }, /* Never used */ |
| #endif |
| }; |
| |
| #ifdef CONFIG_CMA |
| static struct page *__rmqueue_cma_fallback(struct zone *zone, |
| unsigned int order) |
| { |
| return __rmqueue_smallest(zone, order, MIGRATE_CMA); |
| } |
| #else |
| static inline struct page *__rmqueue_cma_fallback(struct zone *zone, |
| unsigned int order) { return NULL; } |
| #endif |
| |
| /* |
| * Move the free pages in a range to the free lists of the requested type. |
| * Note that start_page and end_pages are not aligned on a pageblock |
| * boundary. If alignment is required, use move_freepages_block() |
| */ |
| int move_freepages(struct zone *zone, |
| struct page *start_page, struct page *end_page, |
| int migratetype) |
| { |
| struct page *page; |
| unsigned int order; |
| int pages_moved = 0; |
| |
| #ifndef CONFIG_HOLES_IN_ZONE |
| /* |
| * page_zone is not safe to call in this context when |
| * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant |
| * anyway as we check zone boundaries in move_freepages_block(). |
| * Remove at a later date when no bug reports exist related to |
| * grouping pages by mobility |
| */ |
| VM_BUG_ON(page_zone(start_page) != page_zone(end_page)); |
| #endif |
| |
| for (page = start_page; page <= end_page;) { |
| /* Make sure we are not inadvertently changing nodes */ |
| VM_BUG_ON_PAGE(page_to_nid(page) != zone_to_nid(zone), page); |
| |
| if (!pfn_valid_within(page_to_pfn(page))) { |
| page++; |
| continue; |
| } |
| |
| if (!PageBuddy(page)) { |
| page++; |
| continue; |
| } |
| |
| order = page_order(page); |
| list_move(&page->lru, |
| &zone->free_area[order].free_list[migratetype]); |
| page += 1 << order; |
| pages_moved += 1 << order; |
| } |
| |
| return pages_moved; |
| } |
| |
| int move_freepages_block(struct zone *zone, struct page *page, |
| int migratetype) |
| { |
| unsigned long start_pfn, end_pfn; |
| struct page *start_page, *end_page; |
| |
| start_pfn = page_to_pfn(page); |
| start_pfn = start_pfn & ~(pageblock_nr_pages-1); |
| start_page = pfn_to_page(start_pfn); |
| end_page = start_page + pageblock_nr_pages - 1; |
| end_pfn = start_pfn + pageblock_nr_pages - 1; |
| |
| /* Do not cross zone boundaries */ |
| if (!zone_spans_pfn(zone, start_pfn)) |
| start_page = page; |
| if (!zone_spans_pfn(zone, end_pfn)) |
| return 0; |
| |
| return move_freepages(zone, start_page, end_page, migratetype); |
| } |
| |
| static void change_pageblock_range(struct page *pageblock_page, |
| int start_order, int migratetype) |
| { |
| int nr_pageblocks = 1 << (start_order - pageblock_order); |
| |
| while (nr_pageblocks--) { |
| set_pageblock_migratetype(pageblock_page, migratetype); |
| pageblock_page += pageblock_nr_pages; |
| } |
| } |
| |
| /* |
| * When we are falling back to another migratetype during allocation, try to |
| * steal extra free pages from the same pageblocks to satisfy further |
| * allocations, instead of polluting multiple pageblocks. |
| * |
| * If we are stealing a relatively large buddy page, it is likely there will |
| * be more free pages in the pageblock, so try to steal them all. For |
| * reclaimable and unmovable allocations, we steal regardless of page size, |
| * as fragmentation caused by those allocations polluting movable pageblocks |
| * is worse than movable allocations stealing from unmovable and reclaimable |
| * pageblocks. |
| */ |
| static bool can_steal_fallback(unsigned int order, int start_mt) |
| { |
| /* |
| * Leaving this order check is intended, although there is |
| * relaxed order check in next check. The reason is that |
| * we can actually steal whole pageblock if this condition met, |
| * but, below check doesn't guarantee it and that is just heuristic |
| * so could be changed anytime. |
| */ |
| if (order >= pageblock_order) |
| return true; |
| |
| if (order >= pageblock_order / 2 || |
| start_mt == MIGRATE_RECLAIMABLE || |
| start_mt == MIGRATE_UNMOVABLE || |
| page_group_by_mobility_disabled) |
| return true; |
| |
| return false; |
| } |
| |
| /* |
| * This function implements actual steal behaviour. If order is large enough, |
| * we can steal whole pageblock. If not, we first move freepages in this |
| * pageblock and check whether half of pages are moved or not. If half of |
| * pages are moved, we can change migratetype of pageblock and permanently |
| * use it's pages as requested migratetype in the future. |
| */ |
| static void steal_suitable_fallback(struct zone *zone, struct page *page, |
| int start_type) |
| { |
| unsigned int current_order = page_order(page); |
| int pages; |
| |
| /* Take ownership for orders >= pageblock_order */ |
| if (current_order >= pageblock_order) { |
| change_pageblock_range(page, current_order, start_type); |
| return; |
| } |
| |
| pages = move_freepages_block(zone, page, start_type); |
| |
| /* Claim the whole block if over half of it is free */ |
| if (pages >= (1 << (pageblock_order-1)) || |
| page_group_by_mobility_disabled) |
| set_pageblock_migratetype(page, start_type); |
| } |
| |
| /* |
| * Check whether there is a suitable fallback freepage with requested order. |
| * If only_stealable is true, this function returns fallback_mt only if |
| * we can steal other freepages all together. This would help to reduce |
| * fragmentation due to mixed migratetype pages in one pageblock. |
| */ |
| int find_suitable_fallback(struct free_area *area, unsigned int order, |
| int migratetype, bool only_stealable, bool *can_steal) |
| { |
| int i; |
| int fallback_mt; |
| |
| if (area->nr_free == 0) |
| return -1; |
| |
| *can_steal = false; |
| for (i = 0;; i++) { |
| fallback_mt = fallbacks[migratetype][i]; |
| if (fallback_mt == MIGRATE_TYPES) |
| break; |
| |
| if (list_empty(&area->free_list[fallback_mt])) |
| continue; |
| |
| if (can_steal_fallback(order, migratetype)) |
| *can_steal = true; |
| |
| if (!only_stealable) |
| return fallback_mt; |
| |
| if (*can_steal) |
| return fallback_mt; |
| } |
| |
| return -1; |
| } |
| |
| /* |
| * Reserve a pageblock for exclusive use of high-order atomic allocations if |
| * there are no empty page blocks that contain a page with a suitable order |
| */ |
| static void reserve_highatomic_pageblock(struct page *page, struct zone *zone, |
| unsigned int alloc_order) |
| { |
| int mt; |
| unsigned long max_managed, flags; |
| |
| /* |
| * Limit the number reserved to 1 pageblock or roughly 1% of a zone. |
| * Check is race-prone but harmless. |
| */ |
| max_managed = (zone->managed_pages / 100) + pageblock_nr_pages; |
| if (zone->nr_reserved_highatomic >= max_managed) |
| return; |
| |
| spin_lock_irqsave(&zone->lock, flags); |
| |
| /* Recheck the nr_reserved_highatomic limit under the lock */ |
| if (zone->nr_reserved_highatomic >= max_managed) |
| goto out_unlock; |
| |
| /* Yoink! */ |
| mt = get_pageblock_migratetype(page); |
| if (mt != MIGRATE_HIGHATOMIC && |
| !is_migrate_isolate(mt) && !is_migrate_cma(mt)) { |
| zone->nr_reserved_highatomic += pageblock_nr_pages; |
| set_pageblock_migratetype(page, MIGRATE_HIGHATOMIC); |
| move_freepages_block(zone, page, MIGRATE_HIGHATOMIC); |
| } |
| |
| out_unlock: |
| spin_unlock_irqrestore(&zone->lock, flags); |
| } |
| |
| /* |
| * Used when an allocation is about to fail under memory pressure. This |
| * potentially hurts the reliability of high-order allocations when under |
| * intense memory pressure but failed atomic allocations should be easier |
| * to recover from than an OOM. |
| * |
| * If @force is true, try to unreserve a pageblock even though highatomic |
| * pageblock is exhausted. |
| */ |
| static bool unreserve_highatomic_pageblock(const struct alloc_context *ac, |
| bool force) |
| { |
| struct zonelist *zonelist = ac->zonelist; |
| unsigned long flags; |
| struct zoneref *z; |
| struct zone *zone; |
| struct page *page; |
| int order; |
| bool ret; |
| |
| for_each_zone_zonelist_nodemask(zone, z, zonelist, ac->high_zoneidx, |
| ac->nodemask) { |
| /* |
| * Preserve at least one pageblock unless memory pressure |
| * is really high. |
| */ |
| if (!force && zone->nr_reserved_highatomic <= |
| pageblock_nr_pages) |
| continue; |
| |
| spin_lock_irqsave(&zone->lock, flags); |
| for (order = 0; order < MAX_ORDER; order++) { |
| struct free_area *area = &(zone->free_area[order]); |
| |
| page = list_first_entry_or_null( |
| &area->free_list[MIGRATE_HIGHATOMIC], |
| struct page, lru); |
| if (!page) |
| continue; |
| |
| /* |
| * In page freeing path, migratetype change is racy so |
| * we can counter several free pages in a pageblock |
| * in this loop althoug we changed the pageblock type |
| * from highatomic to ac->migratetype. So we should |
| * adjust the count once. |
| */ |
| if (get_pageblock_migratetype(page) == |
| MIGRATE_HIGHATOMIC) { |
| /* |
| * It should never happen but changes to |
| * locking could inadvertently allow a per-cpu |
| * drain to add pages to MIGRATE_HIGHATOMIC |
| * while unreserving so be safe and watch for |
| * underflows. |
| */ |
| zone->nr_reserved_highatomic -= min( |
| pageblock_nr_pages, |
| zone->nr_reserved_highatomic); |
| } |
| |
| /* |
| * Convert to ac->migratetype and avoid the normal |
| * pageblock stealing heuristics. Minimally, the caller |
| * is doing the work and needs the pages. More |
| * importantly, if the block was always converted to |
| * MIGRATE_UNMOVABLE or another type then the number |
| * of pageblocks that cannot be completely freed |
| * may increase. |
| */ |
| set_pageblock_migratetype(page, ac->migratetype); |
| ret = move_freepages_block(zone, page, ac->migratetype); |
| if (ret) { |
| spin_unlock_irqrestore(&zone->lock, flags); |
| return ret; |
| } |
| } |
| spin_unlock_irqrestore(&zone->lock, flags); |
| } |
| |
| return false; |
| } |
| |
| /* Remove an element from the buddy allocator from the fallback list */ |
| static inline struct page * |
| __rmqueue_fallback(struct zone *zone, unsigned int order, int start_migratetype) |
| { |
| struct free_area *area; |
| unsigned int current_order; |
| struct page *page; |
| int fallback_mt; |
| bool can_steal; |
| |
| /* Find the largest possible block of pages in the other list */ |
| for (current_order = MAX_ORDER-1; |
| current_order >= order && current_order <= MAX_ORDER-1; |
| --current_order) { |
| area = &(zone->free_area[current_order]); |
| fallback_mt = find_suitable_fallback(area, current_order, |
| start_migratetype, false, &can_steal); |
| if (fallback_mt == -1) |
| continue; |
| |
| page = list_first_entry(&area->free_list[fallback_mt], |
| struct page, lru); |
| if (can_steal && |
| get_pageblock_migratetype(page) != MIGRATE_HIGHATOMIC) |
| steal_suitable_fallback(zone, page, start_migratetype); |
| |
| /* Remove the page from the freelists */ |
| area->nr_free--; |
| list_del(&page->lru); |
| rmv_page_order(page); |
| |
| expand(zone, page, order, current_order, area, |
| start_migratetype); |
| /* |
| * The pcppage_migratetype may differ from pageblock's |
| * migratetype depending on the decisions in |
| * find_suitable_fallback(). This is OK as long as it does not |
| * differ for MIGRATE_CMA pageblocks. Those can be used as |
| * fallback only via special __rmqueue_cma_fallback() function |
| */ |
| set_pcppage_migratetype(page, start_migratetype); |
| |
| trace_mm_page_alloc_extfrag(page, order, current_order, |
| start_migratetype, fallback_mt); |
| |
| return page; |
| } |
| |
| return NULL; |
| } |
| |
| /* |
| * Do the hard work of removing an element from the buddy allocator. |
| * Call me with the zone->lock already held. |
| */ |
| static struct page *__rmqueue(struct zone *zone, unsigned int order, |
| int migratetype) |
| { |
| struct page *page; |
| |
| page = __rmqueue_smallest(zone, order, migratetype); |
| if (unlikely(!page)) { |
| if (migratetype == MIGRATE_MOVABLE) |
| page = __rmqueue_cma_fallback(zone, order); |
| |
| if (!page) |
| page = __rmqueue_fallback(zone, order, migratetype); |
| } |
| |
| trace_mm_page_alloc_zone_locked(page, order, migratetype); |
| return page; |
| } |
| |
| /* |
| * Obtain a specified number of elements from the buddy allocator, all under |
| * a single hold of the lock, for efficiency. Add them to the supplied list. |
| * Returns the number of new pages which were placed at *list. |
| */ |
| static int rmqueue_bulk(struct zone *zone, unsigned int order, |
| unsigned long count, struct list_head *list, |
| int migratetype, bool cold) |
| { |
| int i; |
| |
| spin_lock(&zone->lock); |
| for (i = 0; i < count; ++i) { |
| struct page *page = __rmqueue(zone, order, migratetype); |
| if (unlikely(page == NULL)) |
| break; |
| |
| if (unlikely(check_pcp_refill(page))) |
| continue; |
| |
| /* |
| * Split buddy pages returned by expand() are received here |
| * in physical page order. The page is added to the callers and |
| * list and the list head then moves forward. From the callers |
| * perspective, the linked list is ordered by page number in |
| * some conditions. This is useful for IO devices that can |
| * merge IO requests if the physical pages are ordered |
| * properly. |
| */ |
| if (likely(!cold)) |
| list_add(&page->lru, list); |
| else |
| list_add_tail(&page->lru, list); |
| list = &page->lru; |
| if (is_migrate_cma(get_pcppage_migratetype(page))) |
| __mod_zone_page_state(zone, NR_FREE_CMA_PAGES, |
| -(1 << order)); |
| } |
| __mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order)); |
| spin_unlock(&zone->lock); |
| return i; |
| } |
| |
| #ifdef CONFIG_NUMA |
| /* |
| * Called from the vmstat counter updater to drain pagesets of this |
| * currently executing processor on remote nodes after they have |
| * expired. |
| * |
| * Note that this function must be called with the thread pinned to |
| * a single processor. |
| */ |
| void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp) |
| { |
| unsigned long flags; |
| int to_drain, batch; |
| |
| local_irq_save(flags); |
| batch = READ_ONCE(pcp->batch); |
| to_drain = min(pcp->count, batch); |
| if (to_drain > 0) { |
| free_pcppages_bulk(zone, to_drain, pcp); |
| pcp->count -= to_drain; |
| } |
| local_irq_restore(flags); |
| } |
| #endif |
| |
| /* |
| * Drain pcplists of the indicated processor and zone. |
| * |
| * The processor must either be the current processor and the |
| * thread pinned to the current processor or a processor that |
| * is not online. |
| */ |
| static void drain_pages_zone(unsigned int cpu, struct zone *zone) |
| { |
| unsigned long flags; |
| struct per_cpu_pageset *pset; |
| struct per_cpu_pages *pcp; |
| |
| local_irq_save(flags); |
| pset = per_cpu_ptr(zone->pageset, cpu); |
| |
| pcp = &pset->pcp; |
| if (pcp->count) { |
| free_pcppages_bulk(zone, pcp->count, pcp); |
| pcp->count = 0; |
| } |
| local_irq_restore(flags); |
| } |
| |
| /* |
| * Drain pcplists of all zones on the indicated processor. |
| * |
| * The processor must either be the current processor and the |
| * thread pinned to the current processor or a processor that |
| * is not online. |
| */ |
| static void drain_pages(unsigned int cpu) |
| { |
| struct zone *zone; |
| |
| for_each_populated_zone(zone) { |
| drain_pages_zone(cpu, zone); |
| } |
| } |
| |
| /* |
| * Spill all of this CPU's per-cpu pages back into the buddy allocator. |
| * |
| * The CPU has to be pinned. When zone parameter is non-NULL, spill just |
| * the single zone's pages. |
| */ |
| void drain_local_pages(struct zone *zone) |
| { |
| int cpu = smp_processor_id(); |
| |
| if (zone) |
| drain_pages_zone(cpu, zone); |
| else |
| drain_pages(cpu); |
| } |
| |
| /* |
| * Spill all the per-cpu pages from all CPUs back into the buddy allocator. |
| * |
| * When zone parameter is non-NULL, spill just the single zone's pages. |
| * |
| * Note that this code is protected against sending an IPI to an offline |
| * CPU but does not guarantee sending an IPI to newly hotplugged CPUs: |
| * on_each_cpu_mask() blocks hotplug and won't talk to offlined CPUs but |
| * nothing keeps CPUs from showing up after we populated the cpumask and |
| * before the call to on_each_cpu_mask(). |
| */ |
| void drain_all_pages(struct zone *zone) |
| { |
| int cpu; |
| |
| /* |
| * Allocate in the BSS so we wont require allocation in |
| * direct reclaim path for CONFIG_CPUMASK_OFFSTACK=y |
| */ |
| static cpumask_t cpus_with_pcps; |
| |
| /* |
| * We don't care about racing with CPU hotplug event |
| * as offline notification will cause the notified |
| * cpu to drain that CPU pcps and on_each_cpu_mask |
| * disables preemption as part of its processing |
| */ |
| for_each_online_cpu(cpu) { |
| struct per_cpu_pageset *pcp; |
| struct zone *z; |
| bool has_pcps = false; |
| |
| if (zone) { |
| pcp = per_cpu_ptr(zone->pageset, cpu); |
| if (pcp->pcp.count) |
| has_pcps = true; |
| } else { |
| for_each_populated_zone(z) { |
| pcp = per_cpu_ptr(z->pageset, cpu); |
| if (pcp->pcp.count) { |
| has_pcps = true; |
| break; |
| } |
| } |
| } |
| |
| if (has_pcps) |
| cpumask_set_cpu(cpu, &cpus_with_pcps); |
| else |
| cpumask_clear_cpu(cpu, &cpus_with_pcps); |
| } |
| on_each_cpu_mask(&cpus_with_pcps, (smp_call_func_t) drain_local_pages, |
| zone, 1); |
| } |
| |
| #ifdef CONFIG_HIBERNATION |
| |
| void mark_free_pages(struct zone *zone) |
| { |
| unsigned long pfn, max_zone_pfn; |
| unsigned long flags; |
| unsigned int order, t; |
| struct page *page; |
| |
| if (zone_is_empty(zone)) |
| return; |
| |
| spin_lock_irqsave(&zone->lock, flags); |
| |
| max_zone_pfn = zone_end_pfn(zone); |
| for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) |
| if (pfn_valid(pfn)) { |
| page = pfn_to_page(pfn); |
| |
| if (page_zone(page) != zone) |
| continue; |
| |
| if (!swsusp_page_is_forbidden(page)) |
| swsusp_unset_page_free(page); |
| } |
| |
| for_each_migratetype_order(order, t) { |
| list_for_each_entry(page, |
| &zone->free_area[order].free_list[t], lru) { |
| unsigned long i; |
| |
| pfn = page_to_pfn(page); |
| for (i = 0; i < (1UL << order); i++) |
| swsusp_set_page_free(pfn_to_page(pfn + i)); |
| } |
| } |
| spin_unlock_irqrestore(&zone->lock, flags); |
| } |
| #endif /* CONFIG_PM */ |
| |
| /* |
| * Free a 0-order page |
| * cold == true ? free a cold page : free a hot page |
| */ |
| void free_hot_cold_page(struct page *page, bool cold) |
| { |
| struct zone *zone = page_zone(page); |
| struct per_cpu_pages *pcp; |
| unsigned long flags; |
| unsigned long pfn = page_to_pfn(page); |
| int migratetype; |
| |
| if (!free_pcp_prepare(page)) |
| return; |
| |
| migratetype = get_pfnblock_migratetype(page, pfn); |
| set_pcppage_migratetype(page, migratetype); |
| local_irq_save(flags); |
| __count_vm_event(PGFREE); |
| |
| /* |
| * We only track unmovable, reclaimable and movable on pcp lists. |
| * Free ISOLATE pages back to the allocator because they are being |
| * offlined but treat RESERVE as movable pages so we can get those |
| * areas back if necessary. Otherwise, we may have to free |
| * excessively into the page allocator |
| */ |
| if (migratetype >= MIGRATE_PCPTYPES) { |
| if (unlikely(is_migrate_isolate(migratetype))) { |
| free_one_page(zone, page, pfn, 0, migratetype); |
| goto out; |
| } |
| migratetype = MIGRATE_MOVABLE; |
| } |
| |
| pcp = &this_cpu_ptr(zone->pageset)->pcp; |
| if (!cold) |
| list_add(&page->lru, &pcp->lists[migratetype]); |
| else |
| list_add_tail(&page->lru, &pcp->lists[migratetype]); |
| pcp->count++; |
| if (pcp->count >= pcp->high) { |
| unsigned long batch = READ_ONCE(pcp->batch); |
| free_pcppages_bulk(zone, batch, pcp); |
| pcp->count -= batch; |
| } |
| |
| out: |
| local_irq_restore(flags); |
| } |
| |
| /* |
| * Free a list of 0-order pages |
| */ |
| void free_hot_cold_page_list(struct list_head *list, bool cold) |
| { |
| struct page *page, *next; |
| |
| list_for_each_entry_safe(page, next, list, lru) { |
| trace_mm_page_free_batched(page, cold); |
| free_hot_cold_page(page, cold); |
| } |
| } |
| |
| /* |
| * split_page takes a non-compound higher-order page, and splits it into |
| * n (1<<order) sub-pages: page[0..n] |
| * Each sub-page must be freed individually. |
| * |
| * Note: this is probably too low level an operation for use in drivers. |
| * Please consult with lkml before using this in your driver. |
| */ |
| void split_page(struct page *page, unsigned int order) |
| { |
| int i; |
| |
| VM_BUG_ON_PAGE(PageCompound(page), page); |
| VM_BUG_ON_PAGE(!page_count(page), page); |
| |
| #ifdef CONFIG_KMEMCHECK |
| /* |
| * Split shadow pages too, because free(page[0]) would |
| * otherwise free the whole shadow. |
| */ |
| if (kmemcheck_page_is_tracked(page)) |
| split_page(virt_to_page(page[0].shadow), order); |
| #endif |
| |
| for (i = 1; i < (1 << order); i++) |
| set_page_refcounted(page + i); |
| split_page_owner(page, order); |
| } |
| EXPORT_SYMBOL_GPL(split_page); |
| |
| int __isolate_free_page(struct page *page, unsigned int order) |
| { |
| unsigned long watermark; |
| struct zone *zone; |
| int mt; |
| |
| BUG_ON(!PageBuddy(page)); |
| |
| zone = page_zone(page); |
| mt = get_pageblock_migratetype(page); |
| |
| if (!is_migrate_isolate(mt)) { |
| /* |
| * Obey watermarks as if the page was being allocated. We can |
| * emulate a high-order watermark check with a raised order-0 |
| * watermark, because we already know our high-order page |
| * exists. |
| */ |
| watermark = min_wmark_pages(zone) + (1UL << order); |
| if (!zone_watermark_ok(zone, 0, watermark, 0, ALLOC_CMA)) |
| return 0; |
| |
| __mod_zone_freepage_state(zone, -(1UL << order), mt); |
| } |
| |
| /* Remove page from free list */ |
| list_del(&page->lru); |
| zone->free_area[order].nr_free--; |
| rmv_page_order(page); |
| |
| /* |
| * Set the pageblock if the isolated page is at least half of a |
| * pageblock |
| */ |
| if (order >= pageblock_order - 1) { |
| struct page *endpage = page + (1 << order) - 1; |
| for (; page < endpage; page += pageblock_nr_pages) { |
| int mt = get_pageblock_migratetype(page); |
| if (!is_migrate_isolate(mt) && !is_migrate_cma(mt) |
| && mt != MIGRATE_HIGHATOMIC) |
| set_pageblock_migratetype(page, |
| MIGRATE_MOVABLE); |
| } |
| } |
| |
| |
| return 1UL << order; |
| } |
| |
| /* |
| * Update NUMA hit/miss statistics |
| * |
| * Must be called with interrupts disabled. |
| * |
| * When __GFP_OTHER_NODE is set assume the node of the preferred |
| * zone is the local node. This is useful for daemons who allocate |
| * memory on behalf of other processes. |
| */ |
| static inline void zone_statistics(struct zone *preferred_zone, struct zone *z, |
| gfp_t flags) |
| { |
| #ifdef CONFIG_NUMA |
| int local_nid = numa_node_id(); |
| enum zone_stat_item local_stat = NUMA_LOCAL; |
| |
| if (unlikely(flags & __GFP_OTHER_NODE)) { |
| local_stat = NUMA_OTHER; |
| local_nid = preferred_zone->node; |
| } |
| |
| if (z->node == local_nid) { |
| __inc_zone_state(z, NUMA_HIT); |
| __inc_zone_state(z, local_stat); |
| } else { |
| __inc_zone_state(z, NUMA_MISS); |
| __inc_zone_state(preferred_zone, NUMA_FOREIGN); |
| } |
| #endif |
| } |
| |
| /* |
| * Allocate a page from the given zone. Use pcplists for order-0 allocations. |
| */ |
| static inline |
| struct page *buffered_rmqueue(struct zone *preferred_zone, |
| struct zone *zone, unsigned int order, |
| gfp_t gfp_flags, unsigned int alloc_flags, |
| int migratetype) |
| { |
| unsigned long flags; |
| struct page *page; |
| bool cold = ((gfp_flags & __GFP_COLD) != 0); |
| |
| if (likely(order == 0)) { |
| struct per_cpu_pages *pcp; |
| struct list_head *list; |
| |
| local_irq_save(flags); |
| do { |
| pcp = &this_cpu_ptr(zone->pageset)->pcp; |
| list = &pcp->lists[migratetype]; |
| if (list_empty(list)) { |
| pcp->count += rmqueue_bulk(zone, 0, |
| pcp->batch, list, |
| migratetype, cold); |
| if (unlikely(list_empty(list))) |
| goto failed; |
| } |
| |
| if (cold) |
| page = list_last_entry(list, struct page, lru); |
| else |
| page = list_first_entry(list, struct page, lru); |
| |
| list_del(&page->lru); |
| pcp->count--; |
| |
| } while (check_new_pcp(page)); |
| } else { |
| /* |
| * We most definitely don't want callers attempting to |
| * allocate greater than order-1 page units with __GFP_NOFAIL. |
| */ |
| WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1)); |
| spin_lock_irqsave(&zone->lock, flags); |
| |
| do { |
| page = NULL; |
| if (alloc_flags & ALLOC_HARDER) { |
| page = __rmqueue_smallest(zone, order, MIGRATE_HIGHATOMIC); |
| if (page) |
| trace_mm_page_alloc_zone_locked(page, order, migratetype); |
| } |
| if (!page) |
| page = __rmqueue(zone, order, migratetype); |
| } while (page && check_new_pages(page, order)); |
| spin_unlock(&zone->lock); |
| if (!page) |
| goto failed; |
| __mod_zone_freepage_state(zone, -(1 << order), |
| get_pcppage_migratetype(page)); |
| } |
| |
| __count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order); |
| zone_statistics(preferred_zone, zone, gfp_flags); |
| local_irq_restore(flags); |
| |
| VM_BUG_ON_PAGE(bad_range(zone, page), page); |
| return page; |
| |
| failed: |
| local_irq_restore(flags); |
| return NULL; |
| } |
| |
| #ifdef CONFIG_FAIL_PAGE_ALLOC |
| |
| static struct { |
| struct fault_attr attr; |
| |
| bool ignore_gfp_highmem; |
| bool ignore_gfp_reclaim; |
| u32 min_order; |
| } fail_page_alloc = { |
| .attr = FAULT_ATTR_INITIALIZER, |
| .ignore_gfp_reclaim = true, |
| .ignore_gfp_highmem = true, |
| .min_order = 1, |
| }; |
| |
| static int __init setup_fail_page_alloc(char *str) |
| { |
| return setup_fault_attr(&fail_page_alloc.attr, str); |
| } |
| __setup("fail_page_alloc=", setup_fail_page_alloc); |
| |
| static bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) |
| { |
| if (order < fail_page_alloc.min_order) |
| return false; |
| if (gfp_mask & __GFP_NOFAIL) |
| return false; |
| if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM)) |
| return false; |
| if (fail_page_alloc.ignore_gfp_reclaim && |
| (gfp_mask & __GFP_DIRECT_RECLAIM)) |
| return false; |
| |
| return should_fail(&fail_page_alloc.attr, 1 << order); |
| } |
| |
| #ifdef CONFIG_FAULT_INJECTION_DEBUG_FS |
| |
| static int __init fail_page_alloc_debugfs(void) |
| { |
| umode_t mode = S_IFREG | S_IRUSR | S_IWUSR; |
| struct dentry *dir; |
| |
| dir = fault_create_debugfs_attr("fail_page_alloc", NULL, |
| &fail_page_alloc.attr); |
| if (IS_ERR(dir)) |
| return PTR_ERR(dir); |
| |
| if (!debugfs_create_bool("ignore-gfp-wait", mode, dir, |
| &fail_page_alloc.ignore_gfp_reclaim)) |
| goto fail; |
| if (!debugfs_create_bool("ignore-gfp-highmem", mode, dir, |
| &fail_page_alloc.ignore_gfp_highmem)) |
| goto fail; |
| if (!debugfs_create_u32("min-order", mode, dir, |
| &fail_page_alloc.min_order)) |
| goto fail; |
| |
| return 0; |
| fail: |
| debugfs_remove_recursive(dir); |
| |
| return -ENOMEM; |
| } |
| |
| late_initcall(fail_page_alloc_debugfs); |
| |
| #endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */ |
| |
| #else /* CONFIG_FAIL_PAGE_ALLOC */ |
| |
| static inline bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) |
| { |
| return false; |
| } |
| |
| #endif /* CONFIG_FAIL_PAGE_ALLOC */ |
| |
| /* |
| * Return true if free base pages are above 'mark'. For high-order checks it |
| * will return true of the order-0 watermark is reached and there is at least |
| * one free page of a suitable size. Checking now avoids taking the zone lock |
| * to check in the allocation paths if no pages are free. |
| */ |
| bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark, |
| int classzone_idx, unsigned int alloc_flags, |
| long free_pages) |
| { |
| long min = mark; |
| int o; |
| const bool alloc_harder = (alloc_flags & ALLOC_HARDER); |
| |
| /* free_pages may go negative - that's OK */ |
| free_pages -= (1 << order) - 1; |
| |
| if (alloc_flags & ALLOC_HIGH) |
| min -= min / 2; |
| |
| /* |
| * If the caller does not have rights to ALLOC_HARDER then subtract |
| * the high-atomic reserves. This will over-estimate the size of the |
| * atomic reserve but it avoids a search. |
| */ |
| if (likely(!alloc_harder)) |
| free_pages -= z->nr_reserved_highatomic; |
| else |
| min -= min / 4; |
| |
| #ifdef CONFIG_CMA |
| /* If allocation can't use CMA areas don't use free CMA pages */ |
| if (!(alloc_flags & ALLOC_CMA)) |
| free_pages -= zone_page_state(z, NR_FREE_CMA_PAGES); |
| #endif |
| |
| /* |
| * Check watermarks for an order-0 allocation request. If these |
| * are not met, then a high-order request also cannot go ahead |
| * even if a suitable page happened to be free. |
| */ |
| if (free_pages <= min + z->lowmem_reserve[classzone_idx]) |
| return false; |
| |
| /* If this is an order-0 request then the watermark is fine */ |
| if (!order) |
| return true; |
| |
| /* For a high-order request, check at least one suitable page is free */ |
| for (o = order; o < MAX_ORDER; o++) { |
| struct free_area *area = &z->free_area[o]; |
| int mt; |
| |
| if (!area->nr_free) |
| continue; |
| |
| if (alloc_harder) |
| return true; |
| |
| for (mt = 0; mt < MIGRATE_PCPTYPES; mt++) { |
| if (!list_empty(&area->free_list[mt])) |
| return true; |
| } |
| |
| #ifdef CONFIG_CMA |
| if ((alloc_flags & ALLOC_CMA) && |
| !list_empty(&area->free_list[MIGRATE_CMA])) { |
| return true; |
| } |
| #endif |
| } |
| return false; |
| } |
| |
| bool zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark, |
| int classzone_idx, unsigned int alloc_flags) |
| { |
| return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags, |
| zone_page_state(z, NR_FREE_PAGES)); |
| } |
| |
| static inline bool zone_watermark_fast(struct zone *z, unsigned int order, |
| unsigned long mark, int classzone_idx, unsigned int alloc_flags) |
| { |
| long free_pages = zone_page_state(z, NR_FREE_PAGES); |
| long cma_pages = 0; |
| |
| #ifdef CONFIG_CMA |
| /* If allocation can't use CMA areas don't use free CMA pages */ |
| if (!(alloc_flags & ALLOC_CMA)) |
| cma_pages = zone_page_state(z, NR_FREE_CMA_PAGES); |
| #endif |
| |
| /* |
| * Fast check for order-0 only. If this fails then the reserves |
| * need to be calculated. There is a corner case where the check |
| * passes but only the high-order atomic reserve are free. If |
| * the caller is !atomic then it'll uselessly search the free |
| * list. That corner case is then slower but it is harmless. |
| */ |
| if (!order && (free_pages - cma_pages) > mark + z->lowmem_reserve[classzone_idx]) |
| return true; |
| |
| return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags, |
| free_pages); |
| } |
| |
| bool zone_watermark_ok_safe(struct zone *z, unsigned int order, |
| unsigned long mark, int classzone_idx) |
| { |
| long free_pages = zone_page_state(z, NR_FREE_PAGES); |
| |
| if (z->percpu_drift_mark && free_pages < z->percpu_drift_mark) |
| free_pages = zone_page_state_snapshot(z, NR_FREE_PAGES); |
| |
| return __zone_watermark_ok(z, order, mark, classzone_idx, 0, |
| free_pages); |
| } |
| |
| #ifdef CONFIG_NUMA |
| static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone) |
| { |
| return node_distance(zone_to_nid(local_zone), zone_to_nid(zone)) < |
| RECLAIM_DISTANCE; |
| } |
| #else /* CONFIG_NUMA */ |
| static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone) |
| { |
| return true; |
| } |
| #endif /* CONFIG_NUMA */ |
| |
| /* |
| * get_page_from_freelist goes through the zonelist trying to allocate |
| * a page. |
| */ |
| static struct page * |
| get_page_from_freelist(gfp_t gfp_mask, unsigned int order, int alloc_flags, |
| const struct alloc_context *ac) |
| { |
| struct zoneref *z = ac->preferred_zoneref; |
| struct zone *zone; |
| struct pglist_data *last_pgdat_dirty_limit = NULL; |
| |
| /* |
| * Scan zonelist, looking for a zone with enough free. |
| * See also __cpuset_node_allowed() comment in kernel/cpuset.c. |
| */ |
| for_next_zone_zonelist_nodemask(zone, z, ac->zonelist, ac->high_zoneidx, |
| ac->nodemask) { |
| struct page *page; |
| unsigned long mark; |
| |
| if (cpusets_enabled() && |
| (alloc_flags & ALLOC_CPUSET) && |
| !__cpuset_zone_allowed(zone, gfp_mask)) |
| continue; |
| /* |
| * When allocating a page cache page for writing, we |
| * want to get it from a node that is within its dirty |
| * limit, such that no single node holds more than its |
| * proportional share of globally allowed dirty pages. |
| * The dirty limits take into account the node's |
| * lowmem reserves and high watermark so that kswapd |
| * should be able to balance it without having to |
| * write pages from its LRU list. |
| * |
| * XXX: For now, allow allocations to potentially |
| * exceed the per-node dirty limit in the slowpath |
| * (spread_dirty_pages unset) before going into reclaim, |
| * which is important when on a NUMA setup the allowed |
| * nodes are together not big enough to reach the |
| * global limit. The proper fix for these situations |
| * will require awareness of nodes in the |
| * dirty-throttling and the flusher threads. |
| */ |
| if (ac->spread_dirty_pages) { |
| if (last_pgdat_dirty_limit == zone->zone_pgdat) |
| continue; |
| |
| if (!node_dirty_ok(zone->zone_pgdat)) { |
| last_pgdat_dirty_limit = zone->zone_pgdat; |
| continue; |
| } |
| } |
| |
| mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK]; |
| if (!zone_watermark_fast(zone, order, mark, |
| ac_classzone_idx(ac), alloc_flags)) { |
| int ret; |
| |
| /* Checked here to keep the fast path fast */ |
| BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK); |
| if (alloc_flags & ALLOC_NO_WATERMARKS) |
| goto try_this_zone; |
| |
| if (node_reclaim_mode == 0 || |
| !zone_allows_reclaim(ac->preferred_zoneref->zone, zone)) |
| continue; |
| |
| ret = node_reclaim(zone->zone_pgdat, gfp_mask, order); |
| switch (ret) { |
| case NODE_RECLAIM_NOSCAN: |
| /* did not scan */ |
| continue; |
| case NODE_RECLAIM_FULL: |
| /* scanned but unreclaimable */ |
| continue; |
| default: |
| /* did we reclaim enough */ |
| if (zone_watermark_ok(zone, order, mark, |
| ac_classzone_idx(ac), alloc_flags)) |
| goto try_this_zone; |
| |
| continue; |
| } |
| } |
| |
| try_this_zone: |
| page = buffered_rmqueue(ac->preferred_zoneref->zone, zone, order, |
| gfp_mask, alloc_flags, ac->migratetype); |
| if (page) { |
| prep_new_page(page, order, gfp_mask, alloc_flags); |
| |
| /* |
| * If this is a high-order atomic allocation then check |
| * if the pageblock should be reserved for the future |
| */ |
| if (unlikely(order && (alloc_flags & ALLOC_HARDER))) |
| reserve_highatomic_pageblock(page, zone, order); |
| |
| return page; |
| } |
| } |
| |
| return NULL; |
| } |
| |
| /* |
| * Large machines with many possible nodes should not always dump per-node |
| * meminfo in irq context. |
| */ |
| static inline bool should_suppress_show_mem(void) |
| { |
| bool ret = false; |
| |
| #if NODES_SHIFT > 8 |
| ret = in_interrupt(); |
| #endif |
| return ret; |
| } |
| |
| static DEFINE_RATELIMIT_STATE(nopage_rs, |
| DEFAULT_RATELIMIT_INTERVAL, |
| DEFAULT_RATELIMIT_BURST); |
| |
| void warn_alloc(gfp_t gfp_mask, const char *fmt, ...) |
| { |
| unsigned int filter = SHOW_MEM_FILTER_NODES; |
| struct va_format vaf; |
| va_list args; |
| |
| if ((gfp_mask & __GFP_NOWARN) || !__ratelimit(&nopage_rs) || |
| debug_guardpage_minorder() > 0) |
| return; |
| |
| /* |
| * This documents exceptions given to allocations in certain |
| * contexts that are allowed to allocate outside current's set |
| * of allowed nodes. |
| */ |
| if (!(gfp_mask & __GFP_NOMEMALLOC)) |
| if (test_thread_flag(TIF_MEMDIE) || |
| (current->flags & (PF_MEMALLOC | PF_EXITING))) |
| filter &= ~SHOW_MEM_FILTER_NODES; |
| if (in_interrupt() || !(gfp_mask & __GFP_DIRECT_RECLAIM)) |
| filter &= ~SHOW_MEM_FILTER_NODES; |
| |
| pr_warn("%s: ", current->comm); |
| |
| va_start(args, fmt); |
| vaf.fmt = fmt; |
| vaf.va = &args; |
| pr_cont("%pV", &vaf); |
| va_end(args); |
| |
| pr_cont(", mode:%#x(%pGg)\n", gfp_mask, &gfp_mask); |
| |
| dump_stack(); |
| if (!should_suppress_show_mem()) |
| show_mem(filter); |
| } |
| |
| static inline struct page * |
| __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order, |
| const struct alloc_context *ac, unsigned long *did_some_progress) |
| { |
| struct oom_control oc = { |
| .zonelist = ac->zonelist, |
| .nodemask = ac->nodemask, |
| .memcg = NULL, |
| .gfp_mask = gfp_mask, |
| .order = order, |
| }; |
| struct page *page; |
| |
| *did_some_progress = 0; |
| |
| /* |
| * Acquire the oom lock. If that fails, somebody else is |
| * making progress for us. |
| */ |
| if (!mutex_trylock(&oom_lock)) { |
| *did_some_progress = 1; |
| schedule_timeout_uninterruptible(1); |
| return NULL; |
| } |
| |
| /* |
| * Go through the zonelist yet one more time, keep very high watermark |
| * here, this is only to catch a parallel oom killing, we must fail if |
| * we're still under heavy pressure. |
| */ |
| page = get_page_from_freelist(gfp_mask | __GFP_HARDWALL, order, |
| ALLOC_WMARK_HIGH|ALLOC_CPUSET, ac); |
| if (page) |
| goto out; |
| |
| if (!(gfp_mask & __GFP_NOFAIL)) { |
| /* Coredumps can quickly deplete all memory reserves */ |
| if (current->flags & PF_DUMPCORE) |
| goto out; |
| /* The OOM killer will not help higher order allocs */ |
| if (order > PAGE_ALLOC_COSTLY_ORDER) |
| goto out; |
| /* The OOM killer does not needlessly kill tasks for lowmem */ |
| if (ac->high_zoneidx < ZONE_NORMAL) |
| goto out; |
| if (pm_suspended_storage()) |
| goto out; |
| /* |
| * XXX: GFP_NOFS allocations should rather fail than rely on |
| * other request to make a forward progress. |
| * We are in an unfortunate situation where out_of_memory cannot |
| * do much for this context but let's try it to at least get |
| * access to memory reserved if the current task is killed (see |
| * out_of_memory). Once filesystems are ready to handle allocation |
| * failures more gracefully we should just bail out here. |
| */ |
| |
| /* The OOM killer may not free memory on a specific node */ |
| if (gfp_mask & __GFP_THISNODE) |
| goto out; |
| } |
| /* Exhausted what can be done so it's blamo time */ |
| if (out_of_memory(&oc) || WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL)) { |
| *did_some_progress = 1; |
| |
| if (gfp_mask & __GFP_NOFAIL) { |
| page = get_page_from_freelist(gfp_mask, order, |
| ALLOC_NO_WATERMARKS|ALLOC_CPUSET, ac); |
| /* |
| * fallback to ignore cpuset restriction if our nodes |
| * are depleted |
| */ |
| if (!page) |
| page = get_page_from_freelist(gfp_mask, order, |
| ALLOC_NO_WATERMARKS, ac); |
| } |
| } |
| out: |
| mutex_unlock(&oom_lock); |
| return page; |
| } |
| |
| /* |
| * Maximum number of compaction retries wit a progress before OOM |
| * killer is consider as the only way to move forward. |
| */ |
| #define MAX_COMPACT_RETRIES 16 |
| |
| #ifdef CONFIG_COMPACTION |
| /* Try memory compaction for high-order allocations before reclaim */ |
| static struct page * |
| __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, |
| unsigned int alloc_flags, const struct alloc_context *ac, |
| enum compact_priority prio, enum compact_result *compact_result) |
| { |
| struct page *page; |
| |
| if (!order) |
| return NULL; |
| |
| current->flags |= PF_MEMALLOC; |
| *compact_result = try_to_compact_pages(gfp_mask, order, alloc_flags, ac, |
| prio); |
| current->flags &= ~PF_MEMALLOC; |
| |
| if (*compact_result <= COMPACT_INACTIVE) |
| return NULL; |
| |
| /* |
| * At least in one zone compaction wasn't deferred or skipped, so let's |
| * count a compaction stall |
| */ |
| count_vm_event(COMPACTSTALL); |
| |
| page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac); |
| |
| if (page) { |
| struct zone *zone = page_zone(page); |
| |
| zone->compact_blockskip_flush = false; |
| compaction_defer_reset(zone, order, true); |
| count_vm_event(COMPACTSUCCESS); |
| return page; |
| } |
| |
| /* |
| * It's bad if compaction run occurs and fails. The most likely reason |
| * is that pages exist, but not enough to satisfy watermarks. |
| */ |
| count_vm_event(COMPACTFAIL); |
| |
| cond_resched(); |
| |
| return NULL; |
| } |
| |
| static inline bool |
| should_compact_retry(struct alloc_context *ac, int order, int alloc_flags, |
| enum compact_result compact_result, |
| enum compact_priority *compact_priority, |
| int *compaction_retries) |
| { |
| int max_retries = MAX_COMPACT_RETRIES; |
| int min_priority; |
| |
| if (!order) |
| return false; |
| |
| if (compaction_made_progress(compact_result)) |
| (*compaction_retries)++; |
| |
| /* |
| * compaction considers all the zone as desperately out of memory |
| * so it doesn't really make much sense to retry except when the |
| * failure could be caused by insufficient priority |
| */ |
| if (compaction_failed(compact_result)) |
| goto check_priority; |
| |
| /* |
| * make sure the compaction wasn't deferred or didn't bail out early |
| * due to locks contention before we declare that we should give up. |
| * But do not retry if the given zonelist is not suitable for |
| * compaction. |
| */ |
| if (compaction_withdrawn(compact_result)) |
| return compaction_zonelist_suitable(ac, order, alloc_flags); |
| |
| /* |
| * !costly requests are much more important than __GFP_REPEAT |
| * costly ones because they are de facto nofail and invoke OOM |
| * killer to move on while costly can fail and users are ready |
| * to cope with that. 1/4 retries is rather arbitrary but we |
| * would need much more detailed feedback from compaction to |
| * make a better decision. |
| */ |
| if (order > PAGE_ALLOC_COSTLY_ORDER) |
| max_retries /= 4; |
| if (*compaction_retries <= max_retries) |
| return true; |
| |
| /* |
| * Make sure there are attempts at the highest priority if we exhausted |
| * all retries or failed at the lower priorities. |
| */ |
| check_priority: |
| min_priority = (order > PAGE_ALLOC_COSTLY_ORDER) ? |
| MIN_COMPACT_COSTLY_PRIORITY : MIN_COMPACT_PRIORITY; |
| if (*compact_priority > min_priority) { |
| (*compact_priority)--; |
| *compaction_retries = 0; |
| return true; |
| } |
| return false; |
| } |
| #else |
| static inline struct page * |
| __alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, |
| unsigned int alloc_flags, const struct alloc_context *ac, |
| enum compact_priority prio, enum compact_result *compact_result) |
| { |
| *compact_result = COMPACT_SKIPPED; |
| return NULL; |
| } |
| |
| static inline bool |
| should_compact_retry(struct alloc_context *ac, unsigned int order, int alloc_flags, |
| enum compact_result compact_result, |
| enum compact_priority *compact_priority, |
| int *compaction_retries) |
| { |
| struct zone *zone; |
| struct zoneref *z; |
| |
| if (!order || order > PAGE_ALLOC_COSTLY_ORDER) |
| return false; |
| |
| /* |
| * There are setups with compaction disabled which would prefer to loop |
| * inside the allocator rather than hit the oom killer prematurely. |
| * Let's give them a good hope and keep retrying while the order-0 |
| * watermarks are OK. |
| */ |
| for_each_zone_zonelist_nodemask(zone, z, ac->zonelist, ac->high_zoneidx, |
| ac->nodemask) { |
| if (zone_watermark_ok(zone, 0, min_wmark_pages(zone), |
| ac_classzone_idx(ac), alloc_flags)) |
| return true; |
| } |
| return false; |
| } |
| #endif /* CONFIG_COMPACTION */ |
| |
| /* Perform direct synchronous page reclaim */ |
| static int |
| __perform_reclaim(gfp_t gfp_mask, unsigned int order, |
| const struct alloc_context *ac) |
| { |
| struct reclaim_state reclaim_state; |
| int progress; |
| |
| cond_resched(); |
| |
| /* We now go into synchronous reclaim */ |
| cpuset_memory_pressure_bump(); |
| current->flags |= PF_MEMALLOC; |
| lockdep_set_current_reclaim_state(gfp_mask); |
| reclaim_state.reclaimed_slab = 0; |
| current->reclaim_state = &reclaim_state; |
| |
| progress = try_to_free_pages(ac->zonelist, order, gfp_mask, |
| ac->nodemask); |
| |
| current->reclaim_state = NULL; |
| lockdep_clear_current_reclaim_state(); |
| current->flags &= ~PF_MEMALLOC; |
| |
| cond_resched(); |
| |
| return progress; |
| } |
| |
| /* The really slow allocator path where we enter direct reclaim */ |
| static inline struct page * |
| __alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order, |
| unsigned int alloc_flags, const struct alloc_context *ac, |
| unsigned long *did_some_progress) |
| { |
| struct page *page = NULL; |
| bool drained = false; |
| |
| *did_some_progress = __perform_reclaim(gfp_mask, order, ac); |
| if (unlikely(!(*did_some_progress))) |
| return NULL; |
| |
| retry: |
| page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac); |
| |
| /* |
| * If an allocation failed after direct reclaim, it could be because |
| * pages are pinned on the per-cpu lists or in high alloc reserves. |
| * Shrink them them and try again |
| */ |
| if (!page && !drained) { |
| unreserve_highatomic_pageblock(ac, false); |
| drain_all_pages(NULL); |
| drained = true; |
| goto retry; |
| } |
| |
| return page; |
| } |
| |
| static void wake_all_kswapds(unsigned int order, const struct alloc_context *ac) |
| { |
| struct zoneref *z; |
| struct zone *zone; |
| pg_data_t *last_pgdat = NULL; |
| |
| for_each_zone_zonelist_nodemask(zone, z, ac->zonelist, |
| ac->high_zoneidx, ac->nodemask) { |
| if (last_pgdat != zone->zone_pgdat) |
| wakeup_kswapd(zone, order, ac->high_zoneidx); |
| last_pgdat = zone->zone_pgdat; |
| } |
| } |
| |
| static inline unsigned int |
| gfp_to_alloc_flags(gfp_t gfp_mask) |
| { |
| unsigned int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET; |
| |
| /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */ |
| BUILD_BUG_ON(__GFP_HIGH != (__force gfp_t) ALLOC_HIGH); |
| |
| /* |
| * The caller may dip into page reserves a bit more if the caller |
| * cannot run direct reclaim, or if the caller has realtime scheduling |
| * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will |
| * set both ALLOC_HARDER (__GFP_ATOMIC) and ALLOC_HIGH (__GFP_HIGH). |
| */ |
| alloc_flags |= (__force int) (gfp_mask & __GFP_HIGH); |
| |
| if (gfp_mask & __GFP_ATOMIC) { |
| /* |
| * Not worth trying to allocate harder for __GFP_NOMEMALLOC even |
| * if it can't schedule. |
| */ |
| if (!(gfp_mask & __GFP_NOMEMALLOC)) |
| alloc_flags |= ALLOC_HARDER; |
| /* |
| * Ignore cpuset mems for GFP_ATOMIC rather than fail, see the |
| * comment for __cpuset_node_allowed(). |
| */ |
| alloc_flags &= ~ALLOC_CPUSET; |
| } else if (unlikely(rt_task(current)) && !in_interrupt()) |
| alloc_flags |= ALLOC_HARDER; |
| |
| #ifdef CONFIG_CMA |
| if (gfpflags_to_migratetype(gfp_mask) == MIGRATE_MOVABLE) |
| alloc_flags |= ALLOC_CMA; |
| #endif |
| return alloc_flags; |
| } |
| |
| bool gfp_pfmemalloc_allowed(gfp_t gfp_mask) |
| { |
| if (unlikely(gfp_mask & __GFP_NOMEMALLOC)) |
| return false; |
| |
| if (gfp_mask & __GFP_MEMALLOC) |
| return true; |
| if (in_serving_softirq() && (current->flags & PF_MEMALLOC)) |
| return true; |
| if (!in_interrupt() && |
| ((current->flags & PF_MEMALLOC) || |
| unlikely(test_thread_flag(TIF_MEMDIE)))) |
| return true; |
| |
| return false; |
| } |
| |
| /* |
| * Maximum number of reclaim retries without any progress before OOM killer |
| * is consider as the only way to move forward. |
| */ |
| #define MAX_RECLAIM_RETRIES 16 |
| |
| /* |
| * Checks whether it makes sense to retry the reclaim to make a forward progress |
| * for the given allocation request. |
| * The reclaim feedback represented by did_some_progress (any progress during |
| * the last reclaim round) and no_progress_loops (number of reclaim rounds without |
| * any progress in a row) is considered as well as the reclaimable pages on the |
| * applicable zone list (with a backoff mechanism which is a function of |
| * no_progress_loops). |
| * |
| * Returns true if a retry is viable or false to enter the oom path. |
| */ |
| static inline bool |
| should_reclaim_retry(gfp_t gfp_mask, unsigned order, |
| struct alloc_context *ac, int alloc_flags, |
| bool did_some_progress, int *no_progress_loops) |
| { |
| struct zone *zone; |
| struct zoneref *z; |
| |
| /* |
| * Costly allocations might have made a progress but this doesn't mean |
| * their order will become available due to high fragmentation so |
| * always increment the no progress counter for them |
| */ |
| if (did_some_progress && order <= PAGE_ALLOC_COSTLY_ORDER) |
| *no_progress_loops = 0; |
| else |
| (*no_progress_loops)++; |
| |
| /* |
| * Make sure we converge to OOM if we cannot make any progress |
| * several times in the row. |
| */ |
| if (*no_progress_loops > MAX_RECLAIM_RETRIES) { |
| /* Before OOM, exhaust highatomic_reserve */ |
| return unreserve_highatomic_pageblock(ac, true); |
| } |
| |
| /* |
| * Keep reclaiming pages while there is a chance this will lead |
| * somewhere. If none of the target zones can satisfy our allocation |
| * request even if all reclaimable pages are considered then we are |
| * screwed and have to go OOM. |
| */ |
| for_each_zone_zonelist_nodemask(zone, z, ac->zonelist, ac->high_zoneidx, |
| ac->nodemask) { |
| unsigned long available; |
| unsigned long reclaimable; |
| |
| available = reclaimable = zone_reclaimable_pages(zone); |
| available -= DIV_ROUND_UP((*no_progress_loops) * available, |
| MAX_RECLAIM_RETRIES); |
| available += zone_page_state_snapshot(zone, NR_FREE_PAGES); |
| |
| /* |
| * Would the allocation succeed if we reclaimed the whole |
| * available? |
| */ |
| if (__zone_watermark_ok(zone, order, min_wmark_pages(zone), |
| ac_classzone_idx(ac), alloc_flags, available)) { |
| /* |
| * If we didn't make any progress and have a lot of |
| * dirty + writeback pages then we should wait for |
| * an IO to complete to slow down the reclaim and |
| * prevent from pre mature OOM |
| */ |
| if (!did_some_progress) { |
| unsigned long write_pending; |
| |
| write_pending = zone_page_state_snapshot(zone, |
| NR_ZONE_WRITE_PENDING); |
| |
| if (2 * write_pending > reclaimable) { |
| congestion_wait(BLK_RW_ASYNC, HZ/10); |
| return true; |
| } |
| } |
| |
| /* |
| * Memory allocation/reclaim might be called from a WQ |
| * context and the current implementation of the WQ |
| * concurrency control doesn't recognize that |
| * a particular WQ is congested if the worker thread is |
| * looping without ever sleeping. Therefore we have to |
| * do a short sleep here rather than calling |
| * cond_resched(). |
| */ |
| if (current->flags & PF_WQ_WORKER) |
| schedule_timeout_uninterruptible(1); |
| else |
| cond_resched(); |
| |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| static inline struct page * |
| __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, |
| struct alloc_context *ac) |
| { |
| bool can_direct_reclaim = gfp_mask & __GFP_DIRECT_RECLAIM; |
| struct page *page = NULL; |
| unsigned int alloc_flags; |
| unsigned long did_some_progress; |
| enum compact_priority compact_priority = DEF_COMPACT_PRIORITY; |
| enum compact_result compact_result; |
| int compaction_retries = 0; |
| int no_progress_loops = 0; |
| unsigned long alloc_start = jiffies; |
| unsigned int stall_timeout = 10 * HZ; |
| |
| /* |
| * In the slowpath, we sanity check order to avoid ever trying to |
| * reclaim >= MAX_ORDER areas which will never succeed. Callers may |
| * be using allocators in order of preference for an area that is |
| * too large. |
| */ |
| if (order >= MAX_ORDER) { |
| WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN)); |
| return NULL; |
| } |
| |
| /* |
| * We also sanity check to catch abuse of atomic reserves being used by |
| * callers that are not in atomic context. |
| */ |
| if (WARN_ON_ONCE((gfp_mask & (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)) == |
| (__GFP_ATOMIC|__GFP_DIRECT_RECLAIM))) |
| gfp_mask &= ~__GFP_ATOMIC; |
| |
| /* |
| * The fast path uses conservative alloc_flags to succeed only until |
| * kswapd needs to be woken up, and to avoid the cost of setting up |
| * alloc_flags precisely. So we do that now. |
| */ |
| alloc_flags = gfp_to_alloc_flags(gfp_mask); |
| |
| if (gfp_mask & __GFP_KSWAPD_RECLAIM) |
| wake_all_kswapds(order, ac); |
| |
| /* |
| * The adjusted alloc_flags might result in immediate success, so try |
| * that first |
| */ |
| page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac); |
| if (page) |
| goto got_pg; |
| |
| /* |
| * For costly allocations, try direct compaction first, as it's likely |
| * that we have enough base pages and don't need to reclaim. Don't try |
| * that for allocations that are allowed to ignore watermarks, as the |
| * ALLOC_NO_WATERMARKS attempt didn't yet happen. |
| */ |
| if (can_direct_reclaim && order > PAGE_ALLOC_COSTLY_ORDER && |
| !gfp_pfmemalloc_allowed(gfp_mask)) { |
| page = __alloc_pages_direct_compact(gfp_mask, order, |
| alloc_flags, ac, |
| INIT_COMPACT_PRIORITY, |
| &compact_result); |
| if (page) |
| goto got_pg; |
| |
| /* |
| * Checks for costly allocations with __GFP_NORETRY, which |
| * includes THP page fault allocations |
| */ |
| if (gfp_mask & __GFP_NORETRY) { |
| /* |
| * If compaction is deferred for high-order allocations, |
| * it is because sync compaction recently failed. If |
| * this is the case and the caller requested a THP |
| * allocation, we do not want to heavily disrupt the |
| * system, so we fail the allocation instead of entering |
| * direct reclaim. |
| */ |
| if (compact_result == COMPACT_DEFERRED) |
| goto nopage; |
| |
| /* |
| * Looks like reclaim/compaction is worth trying, but |
| * sync compaction could be very expensive, so keep |
| * using async compaction. |
| */ |
| compact_priority = INIT_COMPACT_PRIORITY; |
| } |
| } |
| |
| retry: |
| /* Ensure kswapd doesn't accidentally go to sleep as long as we loop */ |
| if (gfp_mask & __GFP_KSWAPD_RECLAIM) |
| wake_all_kswapds(order, ac); |
| |
| if (gfp_pfmemalloc_allowed(gfp_mask)) |
| alloc_flags = ALLOC_NO_WATERMARKS; |
| |
| /* |
| * Reset the zonelist iterators if memory policies can be ignored. |
| * These allocations are high priority and system rather than user |
| * orientated. |
| */ |
| if (!(alloc_flags & ALLOC_CPUSET) || (alloc_flags & ALLOC_NO_WATERMARKS)) { |
| ac->zonelist = node_zonelist(numa_node_id(), gfp_mask); |
| ac->preferred_zoneref = first_zones_zonelist(ac->zonelist, |
| ac->high_zoneidx, ac->nodemask); |
| } |
| |
| /* Attempt with potentially adjusted zonelist and alloc_flags */ |
| page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac); |
| if (page) |
| goto got_pg; |
| |
| /* Caller is not willing to reclaim, we can't balance anything */ |
| if (!can_direct_reclaim) { |
| /* |
| * All existing users of the __GFP_NOFAIL are blockable, so warn |
| * of any new users that actually allow this type of allocation |
| * to fail. |
| */ |
| WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL); |
| goto nopage; |
| } |
| |
| /* Avoid recursion of direct reclaim */ |
| if (current->flags & PF_MEMALLOC) { |
| /* |
| * __GFP_NOFAIL request from this context is rather bizarre |
| * because we cannot reclaim anything and only can loop waiting |
| * for somebody to do a work for us. |
| */ |
| if (WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL)) { |
| cond_resched(); |
| goto retry; |
| } |
| goto nopage; |
| } |
| |
| /* Avoid allocations with no watermarks from looping endlessly */ |
| if (test_thread_flag(TIF_MEMDIE) && !(gfp_mask & __GFP_NOFAIL)) |
| goto nopage; |
| |
| |
| /* Try direct reclaim and then allocating */ |
| page = __alloc_pages_direct_reclaim(gfp_mask, order, alloc_flags, ac, |
| &did_some_progress); |
| if (page) |
| goto got_pg; |
| |
| /* Try direct compaction and then allocating */ |
| page = __alloc_pages_direct_compact(gfp_mask, order, alloc_flags, ac, |
| compact_priority, &compact_result); |
| if (page) |
| goto got_pg; |
| |
| /* Do not loop if specifically requested */ |
| if (gfp_mask & __GFP_NORETRY) |
| goto nopage; |
| |
| /* |
| * Do not retry costly high order allocations unless they are |
| * __GFP_REPEAT |
| */ |
| if (order > PAGE_ALLOC_COSTLY_ORDER && !(gfp_mask & __GFP_REPEAT)) |
| goto nopage; |
| |
| /* Make sure we know about allocations which stall for too long */ |
| if (time_after(jiffies, alloc_start + stall_timeout)) { |
| warn_alloc(gfp_mask, |
| "page allocation stalls for %ums, order:%u", |
| jiffies_to_msecs(jiffies-alloc_start), order); |
| stall_timeout += 10 * HZ; |
| } |
| |
| if (should_reclaim_retry(gfp_mask, order, ac, alloc_flags, |
| did_some_progress > 0, &no_progress_loops)) |
| goto retry; |
| |
| /* |
| * It doesn't make any sense to retry for the compaction if the order-0 |
| * reclaim is not able to make any progress because the current |
| * implementation of the compaction depends on the sufficient amount |
| * of free memory (see __compaction_suitable) |
| */ |
| if (did_some_progress > 0 && |
| should_compact_retry(ac, order, alloc_flags, |
| compact_result, &compact_priority, |
| &compaction_retries)) |
| goto retry; |
| |
| /* Reclaim has failed us, start killing things */ |
| page = __alloc_pages_may_oom(gfp_mask, order, ac, &did_some_progress); |
| if (page) |
| goto got_pg; |
| |
| /* Retry as long as the OOM killer is making progress */ |
| if (did_some_progress) { |
| no_progress_loops = 0; |
| goto retry; |
| } |
| |
| nopage: |
| warn_alloc(gfp_mask, |
| "page allocation failure: order:%u", order); |
| got_pg: |
| return page; |
| } |
| |
| /* |
| * This is the 'heart' of the zoned buddy allocator. |
| */ |
| struct page * |
| __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, |
| struct zonelist *zonelist, nodemask_t *nodemask) |
| { |
| struct page *page; |
| unsigned int cpuset_mems_cookie; |
| unsigned int alloc_flags = ALLOC_WMARK_LOW; |
| gfp_t alloc_mask = gfp_mask; /* The gfp_t that was actually used for allocation */ |
| struct alloc_context ac = { |
| .high_zoneidx = gfp_zone(gfp_mask), |
| .zonelist = zonelist, |
| .nodemask = nodemask, |
| .migratetype = gfpflags_to_migratetype(gfp_mask), |
| }; |
| |
| if (cpusets_enabled()) { |
| alloc_mask |= __GFP_HARDWALL; |
| alloc_flags |= ALLOC_CPUSET; |
| if (!ac.nodemask) |
| ac.nodemask = &cpuset_current_mems_allowed; |
| } |
| |
| gfp_mask &= gfp_allowed_mask; |
| |
| lockdep_trace_alloc(gfp_mask); |
| |
| might_sleep_if(gfp_mask & __GFP_DIRECT_RECLAIM); |
| |
| if (should_fail_alloc_page(gfp_mask, order)) |
| return NULL; |
| |
| /* |
| * Check the zones suitable for the gfp_mask contain at least one |
| * valid zone. It's possible to have an empty zonelist as a result |
| * of __GFP_THISNODE and a memoryless node |
| */ |
| if (unlikely(!zonelist->_zonerefs->zone)) |
| return NULL; |
| |
| if (IS_ENABLED(CONFIG_CMA) && ac.migratetype == MIGRATE_MOVABLE) |
| alloc_flags |= ALLOC_CMA; |
| |
| retry_cpuset: |
| cpuset_mems_cookie = read_mems_allowed_begin(); |
| |
| /* Dirty zone balancing only done in the fast path */ |
| ac.spread_dirty_pages = (gfp_mask & __GFP_WRITE); |
| |
| /* |
| * The preferred zone is used for statistics but crucially it is |
| * also used as the starting point for the zonelist iterator. It |
| * may get reset for allocations that ignore memory policies. |
| */ |
| ac.preferred_zoneref = first_zones_zonelist(ac.zonelist, |
| ac.high_zoneidx, ac.nodemask); |
| if (!ac.preferred_zoneref) { |
| page = NULL; |
| goto no_zone; |
| } |
| |
| /* First allocation attempt */ |
| page = get_page_from_freelist(alloc_mask, order, alloc_flags, &ac); |
| if (likely(page)) |
| goto out; |
| |
| /* |
| * Runtime PM, block IO and its error handling path can deadlock |
| * because I/O on the device might not complete. |
| */ |
| alloc_mask = memalloc_noio_flags(gfp_mask); |
| ac.spread_dirty_pages = false; |
| |
| /* |
| * Restore the original nodemask if it was potentially replaced with |
| * &cpuset_current_mems_allowed to optimize the fast-path attempt. |
| */ |
| if (cpusets_enabled()) |
| ac.nodemask = nodemask; |
| page = __alloc_pages_slowpath(alloc_mask, order, &ac); |
| |
| no_zone: |
| /* |
| * When updating a task's mems_allowed, it is possible to race with |
| * parallel threads in such a way that an allocation can fail while |
| * the mask is being updated. If a page allocation is about to fail, |
| * check if the cpuset changed during allocation and if so, retry. |
| */ |
| if (unlikely(!page && read_mems_allowed_retry(cpuset_mems_cookie))) { |
| alloc_mask = gfp_mask; |
| goto retry_cpuset; |
| } |
| |
| out: |
| if (memcg_kmem_enabled() && (gfp_mask & __GFP_ACCOUNT) && page && |
| unlikely(memcg_kmem_charge(page, gfp_mask, order) != 0)) { |
| __free_pages(page, order); |
| page = NULL; |
| } |
| |
| if (kmemcheck_enabled && page) |
| kmemcheck_pagealloc_alloc(page, order, gfp_mask); |
| |
| trace_mm_page_alloc(page, order, alloc_mask, ac.migratetype); |
| |
| return page; |
| } |
| EXPORT_SYMBOL(__alloc_pages_nodemask); |
| |
| /* |
| * Common helper functions. |
| */ |
| unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order) |
| { |
| struct page *page; |
| |
| /* |
| * __get_free_pages() returns a 32-bit address, which cannot represent |
| * a highmem page |
| */ |
| VM_BUG_ON((gfp_mask & __GFP_HIGHMEM) != 0); |
| |
| page = alloc_pages(gfp_mask, order); |
| if (!page) |
| return 0; |
| return (unsigned long) page_address(page); |
| } |
| EXPORT_SYMBOL(__get_free_pages); |
| |
| unsigned long get_zeroed_page(gfp_t gfp_mask) |
| { |
| return __get_free_pages(gfp_mask | __GFP_ZERO, 0); |
| } |
| EXPORT_SYMBOL(get_zeroed_page); |
| |
| void __free_pages(struct page *page, unsigned int order) |
| { |
| if (put_page_testzero(page)) { |
| if (order == 0) |
| free_hot_cold_page(page, false); |
| else |
| __free_pages_ok(page, order); |
| } |
| } |
| |
| EXPORT_SYMBOL(__free_pages); |
| |
| void free_pages(unsigned long addr, unsigned int order) |
| { |
| if (addr != 0) { |
| VM_BUG_ON(!virt_addr_valid((void *)addr)); |
| __free_pages(virt_to_page((void *)addr), order); |
| } |
| } |
| |
| EXPORT_SYMBOL(free_pages); |
| |
| /* |
| * Page Fragment: |
| * An arbitrary-length arbitrary-offset area of memory which resides |
| * within a 0 or higher order page. Multiple fragments within that page |
| * are individually refcounted, in the page's reference counter. |
| * |
| * The page_frag functions below provide a simple allocation framework for |
| * page fragments. This is used by the network stack and network device |
| * drivers to provide a backing region of memory for use as either an |
| * sk_buff->head, or to be used in the "frags" portion of skb_shared_info. |
| */ |
| static struct page *__page_frag_refill(struct page_frag_cache *nc, |
| gfp_t gfp_mask) |
| { |
| struct page *page = NULL; |
| gfp_t gfp = gfp_mask; |
| |
| #if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE) |
| gfp_mask |= __GFP_COMP | __GFP_NOWARN | __GFP_NORETRY | |
| __GFP_NOMEMALLOC; |
| page = alloc_pages_node(NUMA_NO_NODE, gfp_mask, |
| PAGE_FRAG_CACHE_MAX_ORDER); |
| nc->size = page ? PAGE_FRAG_CACHE_MAX_SIZE : PAGE_SIZE; |
| #endif |
| if (unlikely(!page)) |
| page = alloc_pages_node(NUMA_NO_NODE, gfp, 0); |
| |
| nc->va = page ? page_address(page) : NULL; |
| |
| return page; |
| } |
| |
| void *__alloc_page_frag(struct page_frag_cache *nc, |
| unsigned int fragsz, gfp_t gfp_mask) |
| { |
| unsigned int size = PAGE_SIZE; |
| struct page *page; |
| int offset; |
| |
| if (unlikely(!nc->va)) { |
| refill: |
| page = __page_frag_refill(nc, gfp_mask); |
| if (!page) |
| return NULL; |
| |
| #if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE) |
| /* if size can vary use size else just use PAGE_SIZE */ |
| size = nc->size; |
| #endif |
| /* Even if we own the page, we do not use atomic_set(). |
| * This would break get_page_unless_zero() users. |
| */ |
| page_ref_add(page, size - 1); |
| |
| /* reset page count bias and offset to start of new frag */ |
| nc->pfmemalloc = page_is_pfmemalloc(page); |
| nc->pagecnt_bias = size; |
| nc->offset = size; |
| } |
| |
| offset = nc->offset - fragsz; |
| if (unlikely(offset < 0)) { |
| page = virt_to_page(nc->va); |
| |
| if (!page_ref_sub_and_test(page, nc->pagecnt_bias)) |
| goto refill; |
| |
| #if (PAGE_SIZE < PAGE_FRAG_CACHE_MAX_SIZE) |
| /* if size can vary use size else just use PAGE_SIZE */ |
| size = nc->size; |
| #endif |
| /* OK, page count is 0, we can safely set it */ |
| set_page_count(page, size); |
| |
| /* reset page count bias and offset to start of new frag */ |
| nc->pagecnt_bias = size; |
| offset = size - fragsz; |
| } |
| |
| nc->pagecnt_bias--; |
| nc->offset = offset; |
| |
| return nc->va + offset; |
| } |
| EXPORT_SYMBOL(__alloc_page_frag); |
| |
| /* |
| * Frees a page fragment allocated out of either a compound or order 0 page. |
| */ |
| void __free_page_frag(void *addr) |
| { |
| struct page *page = virt_to_head_page(addr); |
| |
| if (unlikely(put_page_testzero(page))) |
| __free_pages_ok(page, compound_order(page)); |
| } |
| EXPORT_SYMBOL(__free_page_frag); |
| |
| static void *make_alloc_exact(unsigned long addr, unsigned int order, |
| size_t size) |
| { |
| if (addr) { |
| unsigned long alloc_end = addr + (PAGE_SIZE << order); |
| unsigned long used = addr + PAGE_ALIGN(size); |
| |
| split_page(virt_to_page((void *)addr), order); |
| while (used < alloc_end) { |
| free_page(used); |
| used += PAGE_SIZE; |
| } |
| } |
| return (void *)addr; |
| } |
| |
| /** |
| * alloc_pages_exact - allocate an exact number physically-contiguous pages. |
| * @size: the number of bytes to allocate |
| * @gfp_mask: GFP flags for the allocation |
| * |
| * This function is similar to alloc_pages(), except that it allocates the |
| * minimum number of pages to satisfy the request. alloc_pages() can only |
| * allocate memory in power-of-two pages. |
| * |
| * This function is also limited by MAX_ORDER. |
| * |
| * Memory allocated by this function must be released by free_pages_exact(). |
| */ |
| void *alloc_pages_exact(size_t size, gfp_t gfp_mask) |
| { |
| unsigned int order = get_order(size); |
| unsigned long addr; |
| |
| addr = __get_free_pages(gfp_mask, order); |
| return make_alloc_exact(addr, order, size); |
| } |
| EXPORT_SYMBOL(alloc_pages_exact); |
| |
| /** |
| * alloc_pages_exact_nid - allocate an exact number of physically-contiguous |
| * pages on a node. |
| * @nid: the preferred node ID where memory should be allocated |
| * @size: the number of bytes to allocate |
| * @gfp_mask: GFP flags for the allocation |
| * |
| * Like alloc_pages_exact(), but try to allocate on node nid first before falling |
| * back. |
| */ |
| void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask) |
| { |
| unsigned int order = get_order(size); |
| struct page *p = alloc_pages_node(nid, gfp_mask, order); |
| if (!p) |
| return NULL; |
| return make_alloc_exact((unsigned long)page_address(p), order, size); |
| } |
| |
| /** |
| * free_pages_exact - release memory allocated via alloc_pages_exact() |
| * @virt: the value returned by alloc_pages_exact. |
| * @size: size of allocation, same value as passed to alloc_pages_exact(). |
| * |
| * Release the memory allocated by a previous call to alloc_pages_exact. |
| */ |
| void free_pages_exact(void *virt, size_t size) |
| { |
| unsigned long addr = (unsigned long)virt; |
| unsigned long end = addr + PAGE_ALIGN(size); |
| |
| while (addr < end) { |
| free_page(addr); |
| addr += PAGE_SIZE; |
| } |
| } |
| EXPORT_SYMBOL(free_pages_exact); |
| |
| /** |
| * nr_free_zone_pages - count number of pages beyond high watermark |
| * @offset: The zone index of the highest zone |
| * |
| * nr_free_zone_pages() counts the number of counts pages which are beyond the |
| * high watermark within all zones at or below a given zone index. For each |
| * zone, the number of pages is calculated as: |
| * managed_pages - high_pages |
| */ |
| static unsigned long nr_free_zone_pages(int offset) |
| { |
| struct zoneref *z; |
| struct zone *zone; |
| |
| /* Just pick one node, since fallback list is circular */ |
| unsigned long sum = 0; |
| |
| struct zonelist *zonelist = node_zonelist(numa_node_id(), GFP_KERNEL); |
| |
| for_each_zone_zonelist(zone, z, zonelist, offset) { |
| unsigned long size = zone->managed_pages; |
| unsigned long high = high_wmark_pages(zone); |
| if (size > high) |
| sum += size - high; |
| } |
| |
| return sum; |
| } |
| |
| /** |
| * nr_free_buffer_pages - count number of pages beyond high watermark |
| * |
| * nr_free_buffer_pages() counts the number of pages which are beyond the high |
| * watermark within ZONE_DMA and ZONE_NORMAL. |
| */ |
| unsigned long nr_free_buffer_pages(void) |
| { |
| return nr_free_zone_pages(gfp_zone(GFP_USER)); |
| } |
| EXPORT_SYMBOL_GPL(nr_free_buffer_pages); |
| |
| /** |
| * nr_free_pagecache_pages - count number of pages beyond high watermark |
| * |
| * nr_free_pagecache_pages() counts the number of pages which are beyond the |
| * high watermark within all zones. |
| */ |
| unsigned long nr_free_pagecache_pages(void) |
| { |
| return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE)); |
| } |
| |
| static inline void show_node(struct zone *zone) |
| { |
| if (IS_ENABLED(CONFIG_NUMA)) |
| printk("Node %d ", zone_to_nid(zone)); |
| } |
| |
| long si_mem_available(void) |
| { |
| long available; |
| unsigned long pagecache; |
| unsigned long wmark_low = 0; |
| unsigned long pages[NR_LRU_LISTS]; |
| struct zone *zone; |
| int lru; |
| |
| for (lru = LRU_BASE; lru < NR_LRU_LISTS; lru++) |
| pages[lru] = global_node_page_state(NR_LRU_BASE + lru); |
| |
| for_each_zone(zone) |
| wmark_low += zone->watermark[WMARK_LOW]; |
| |
| /* |
| * Estimate the amount of memory available for userspace allocations, |
| * without causing swapping. |
| */ |
| available = global_page_state(NR_FREE_PAGES) - totalreserve_pages; |
| |
| /* |
| * Not all the page cache can be freed, otherwise the system will |
| * start swapping. Assume at least half of the page cache, or the |
| * low watermark worth of cache, needs to stay. |
| */ |
| pagecache = pages[LRU_ACTIVE_FILE] + pages[LRU_INACTIVE_FILE]; |
| pagecache -= min(pagecache / 2, wmark_low); |
| available += pagecache; |
| |
| /* |
| * Part of the reclaimable slab consists of items that are in use, |
| * and cannot be freed. Cap this estimate at the low watermark. |
| */ |
| available += global_page_state(NR_SLAB_RECLAIMABLE) - |
| min(global_page_state(NR_SLAB_RECLAIMABLE) / 2, wmark_low); |
| |
| if (available < 0) |
| available = 0; |
| return available; |
| } |
| EXPORT_SYMBOL_GPL(si_mem_available); |
| |
| void si_meminfo(struct sysinfo *val) |
| { |
| val->totalram = totalram_pages; |
| val->sharedram = global_node_page_state(NR_SHMEM); |
| val->freeram = global_page_state(NR_FREE_PAGES); |
| val->bufferram = nr_blockdev_pages(); |
| val->totalhigh = totalhigh_pages; |
| val->freehigh = nr_free_highpages(); |
| val->mem_unit = PAGE_SIZE; |
| } |
| |
| EXPORT_SYMBOL(si_meminfo); |
| |
| #ifdef CONFIG_NUMA |
| void si_meminfo_node(struct sysinfo *val, int nid) |
| { |
| int zone_type; /* needs to be signed */ |
| unsigned long managed_pages = 0; |
| unsigned long managed_highpages = 0; |
| unsigned long free_highpages = 0; |
| pg_data_t *pgdat = NODE_DATA(nid); |
| |
| for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) |
| managed_pages += pgdat->node_zones[zone_type].managed_pages; |
| val->totalram = managed_pages; |
| val->sharedram = node_page_state(pgdat, NR_SHMEM); |
| val->freeram = sum_zone_node_page_state(nid, NR_FREE_PAGES); |
| #ifdef CONFIG_HIGHMEM |
| for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) { |
| struct zone *zone = &pgdat->node_zones[zone_type]; |
| |
| if (is_highmem(zone)) { |
| managed_highpages += zone->managed_pages; |
| free_highpages += zone_page_state(zone, NR_FREE_PAGES); |
| } |
| } |
| val->totalhigh = managed_highpages; |
| val->freehigh = free_highpages; |
| #else |
| val->totalhigh = managed_highpages; |
| val->freehigh = free_highpages; |
| #endif |
| val->mem_unit = PAGE_SIZE; |
| } |
| #endif |
| |
| /* |
| * Determine whether the node should be displayed or not, depending on whether |
| * SHOW_MEM_FILTER_NODES was passed to show_free_areas(). |
| */ |
| bool skip_free_areas_node(unsigned int flags, int nid) |
| { |
| bool ret = false; |
| unsigned int cpuset_mems_cookie; |
| |
| if (!(flags & SHOW_MEM_FILTER_NODES)) |
| goto out; |
| |
| do { |
| cpuset_mems_cookie = read_mems_allowed_begin(); |
| ret = !node_isset(nid, cpuset_current_mems_allowed); |
| } while (read_mems_allowed_retry(cpuset_mems_cookie)); |
| out: |
| return ret; |
| } |
| |
| #define K(x) ((x) << (PAGE_SHIFT-10)) |
| |
| static void show_migration_types(unsigned char type) |
| { |
| static const char types[MIGRATE_TYPES] = { |
| [MIGRATE_UNMOVABLE] = 'U', |
| [MIGRATE_MOVABLE] = 'M', |
| [MIGRATE_RECLAIMABLE] = 'E', |
| [MIGRATE_HIGHATOMIC] = 'H', |
| #ifdef CONFIG_CMA |
| [MIGRATE_CMA] = 'C', |
| #endif |
| #ifdef CONFIG_MEMORY_ISOLATION |
| [MIGRATE_ISOLATE] = 'I', |
| #endif |
| }; |
| char tmp[MIGRATE_TYPES + 1]; |
| char *p = tmp; |
| int i; |
| |
| for (i = 0; i < MIGRATE_TYPES; i++) { |
| if (type & (1 << i)) |
| *p++ = types[i]; |
| } |
| |
| *p = '\0'; |
| printk(KERN_CONT "(%s) ", tmp); |
| } |
| |
| /* |
| * Show free area list (used inside shift_scroll-lock stuff) |
| * We also calculate the percentage fragmentation. We do this by counting the |
| * memory on each free list with the exception of the first item on the list. |
| * |
| * Bits in @filter: |
| * SHOW_MEM_FILTER_NODES: suppress nodes that are not allowed by current's |
| * cpuset. |
| */ |
| void show_free_areas(unsigned int filter) |
| { |
| unsigned long free_pcp = 0; |
| int cpu; |
| struct zone *zone; |
| pg_data_t *pgdat; |
| |
| for_each_populated_zone(zone) { |
| if (skip_free_areas_node(filter, zone_to_nid(zone))) |
| continue; |
| |
| for_each_online_cpu(cpu) |
| free_pcp += per_cpu_ptr(zone->pageset, cpu)->pcp.count; |
| } |
| |
| printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n" |
| " active_file:%lu inactive_file:%lu isolated_file:%lu\n" |
| " unevictable:%lu dirty:%lu writeback:%lu unstable:%lu\n" |
| " slab_reclaimable:%lu slab_unreclaimable:%lu\n" |
| " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n" |
| " free:%lu free_pcp:%lu free_cma:%lu\n", |
| global_node_page_state(NR_ACTIVE_ANON), |
| global_node_page_state(NR_INACTIVE_ANON), |
| global_node_page_state(NR_ISOLATED_ANON), |
| global_node_page_state(NR_ACTIVE_FILE), |
| global_node_page_state(NR_INACTIVE_FILE), |
| global_node_page_state(NR_ISOLATED_FILE), |
| global_node_page_state(NR_UNEVICTABLE), |
| global_node_page_state(NR_FILE_DIRTY), |
| global_node_page_state(NR_WRITEBACK), |
| global_node_page_state(NR_UNSTABLE_NFS), |
| global_page_state(NR_SLAB_RECLAIMABLE), |
| global_page_state(NR_SLAB_UNRECLAIMABLE), |
| global_node_page_state(NR_FILE_MAPPED), |
| global_node_page_state(NR_SHMEM), |
| global_page_state(NR_PAGETABLE), |
| global_page_state(NR_BOUNCE), |
| global_page_state(NR_FREE_PAGES), |
| free_pcp, |
| global_page_state(NR_FREE_CMA_PAGES)); |
| |
| for_each_online_pgdat(pgdat) { |
| printk("Node %d" |
| " active_anon:%lukB" |
| " inactive_anon:%lukB" |
| " active_file:%lukB" |
| " inactive_file:%lukB" |
| " unevictable:%lukB" |
| " isolated(anon):%lukB" |
| " isolated(file):%lukB" |
| " mapped:%lukB" |
| " dirty:%lukB" |
| " writeback:%lukB" |
| " shmem:%lukB" |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| " shmem_thp: %lukB" |
| " shmem_pmdmapped: %lukB" |
| " anon_thp: %lukB" |
| #endif |
| " writeback_tmp:%lukB" |
| " unstable:%lukB" |
| " pages_scanned:%lu" |
| " all_unreclaimable? %s" |
| "\n", |
| pgdat->node_id, |
| K(node_page_state(pgdat, NR_ACTIVE_ANON)), |
| K(node_page_state(pgdat, NR_INACTIVE_ANON)), |
| K(node_page_state(pgdat, NR_ACTIVE_FILE)), |
| K(node_page_state(pgdat, NR_INACTIVE_FILE)), |
| K(node_page_state(pgdat, NR_UNEVICTABLE)), |
| K(node_page_state(pgdat, NR_ISOLATED_ANON)), |
| K(node_page_state(pgdat, NR_ISOLATED_FILE)), |
| K(node_page_state(pgdat, NR_FILE_MAPPED)), |
| K(node_page_state(pgdat, NR_FILE_DIRTY)), |
| K(node_page_state(pgdat, NR_WRITEBACK)), |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| K(node_page_state(pgdat, NR_SHMEM_THPS) * HPAGE_PMD_NR), |
| K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED) |
| * HPAGE_PMD_NR), |
| K(node_page_state(pgdat, NR_ANON_THPS) * HPAGE_PMD_NR), |
| #endif |
| K(node_page_state(pgdat, NR_SHMEM)), |
| K(node_page_state(pgdat, NR_WRITEBACK_TEMP)), |
| K(node_page_state(pgdat, NR_UNSTABLE_NFS)), |
| node_page_state(pgdat, NR_PAGES_SCANNED), |
| !pgdat_reclaimable(pgdat) ? "yes" : "no"); |
| } |
| |
| for_each_populated_zone(zone) { |
| int i; |
| |
| if (skip_free_areas_node(filter, zone_to_nid(zone))) |
| continue; |
| |
| free_pcp = 0; |
| for_each_online_cpu(cpu) |
| free_pcp += per_cpu_ptr(zone->pageset, cpu)->pcp.count; |
| |
| show_node(zone); |
| printk(KERN_CONT |
| "%s" |
| " free:%lukB" |
| " min:%lukB" |
| " low:%lukB" |
| " high:%lukB" |
| " active_anon:%lukB" |
| " inactive_anon:%lukB" |
| " active_file:%lukB" |
| " inactive_file:%lukB" |
| " unevictable:%lukB" |
| " writepending:%lukB" |
| " present:%lukB" |
| " managed:%lukB" |
| " mlocked:%lukB" |
| " slab_reclaimable:%lukB" |
| " slab_unreclaimable:%lukB" |
| " kernel_stack:%lukB" |
| " pagetables:%lukB" |
| " bounce:%lukB" |
| " free_pcp:%lukB" |
| " local_pcp:%ukB" |
| " free_cma:%lukB" |
| "\n", |
| zone->name, |
| K(zone_page_state(zone, NR_FREE_PAGES)), |
| K(min_wmark_pages(zone)), |
| K(low_wmark_pages(zone)), |
| K(high_wmark_pages(zone)), |
| K(zone_page_state(zone, NR_ZONE_ACTIVE_ANON)), |
| K(zone_page_state(zone, NR_ZONE_INACTIVE_ANON)), |
| K(zone_page_state(zone, NR_ZONE_ACTIVE_FILE)), |
| K(zone_page_state(zone, NR_ZONE_INACTIVE_FILE)), |
| K(zone_page_state(zone, NR_ZONE_UNEVICTABLE)), |
| K(zone_page_state(zone, NR_ZONE_WRITE_PENDING)), |
| K(zone->present_pages), |
| K(zone->managed_pages), |
| K(zone_page_state(zone, NR_MLOCK)), |
| K(zone_page_state(zone, NR_SLAB_RECLAIMABLE)), |
| K(zone_page_state(zone, NR_SLAB_UNRECLAIMABLE)), |
| zone_page_state(zone, NR_KERNEL_STACK_KB), |
| K(zone_page_state(zone, NR_PAGETABLE)), |
| K(zone_page_state(zone, NR_BOUNCE)), |
| K(free_pcp), |
| K(this_cpu_read(zone->pageset->pcp.count)), |
| K(zone_page_state(zone, NR_FREE_CMA_PAGES))); |
| printk("lowmem_reserve[]:"); |
| for (i = 0; i < MAX_NR_ZONES; i++) |
| printk(KERN_CONT " %ld", zone->lowmem_reserve[i]); |
| printk(KERN_CONT "\n"); |
| } |
| |
| for_each_populated_zone(zone) { |
| unsigned int order; |
| unsigned long nr[MAX_ORDER], flags, total = 0; |
| unsigned char types[MAX_ORDER]; |
| |
| if (skip_free_areas_node(filter, zone_to_nid(zone))) |
| continue; |
| show_node(zone); |
| printk(KERN_CONT "%s: ", zone->name); |
| |
| spin_lock_irqsave(&zone->lock, flags); |
| for (order = 0; order < MAX_ORDER; order++) { |
| struct free_area *area = &zone->free_area[order]; |
| int type; |
| |
| nr[order] = area->nr_free; |
| total += nr[order] << order; |
| |
| types[order] = 0; |
| for (type = 0; type < MIGRATE_TYPES; type++) { |
| if (!list_empty(&area->free_list[type])) |
| types[order] |= 1 << type; |
| } |
| } |
| spin_unlock_irqrestore(&zone->lock, flags); |
| for (order = 0; order < MAX_ORDER; order++) { |
| printk(KERN_CONT "%lu*%lukB ", |
| nr[order], K(1UL) << order); |
| if (nr[order]) |
| show_migration_types(types[order]); |
| } |
| printk(KERN_CONT "= %lukB\n", K(total)); |
| } |
| |
| hugetlb_show_meminfo(); |
| |
| printk("%ld total pagecache pages\n", global_node_page_state(NR_FILE_PAGES)); |
| |
| show_swap_cache_info(); |
| } |
| |
| static void zoneref_set_zone(struct zone *zone, struct zoneref *zoneref) |
| { |
| zoneref->zone = zone; |
| zoneref->zone_idx = zone_idx(zone); |
| } |
| |
| /* |
| * Builds allocation fallback zone lists. |
| * |
| * Add all populated zones of a node to the zonelist. |
| */ |
| static int build_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist, |
| int nr_zones) |
| { |
| struct zone *zone; |
| enum zone_type zone_type = MAX_NR_ZONES; |
| |
| do { |
| zone_type--; |
| zone = pgdat->node_zones + zone_type; |
| if (managed_zone(zone)) { |
| zoneref_set_zone(zone, |
| &zonelist->_zonerefs[nr_zones++]); |
| check_highest_zone(zone_type); |
| } |
| } while (zone_type); |
| |
| return nr_zones; |
| } |
| |
| |
| /* |
| * zonelist_order: |
| * 0 = automatic detection of better ordering. |
| * 1 = order by ([node] distance, -zonetype) |
| * 2 = order by (-zonetype, [node] distance) |
| * |
| * If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create |
| * the same zonelist. So only NUMA can configure this param. |
| */ |
| #define ZONELIST_ORDER_DEFAULT 0 |
| #define ZONELIST_ORDER_NODE 1 |
| #define ZONELIST_ORDER_ZONE 2 |
| |
| /* zonelist order in the kernel. |
| * set_zonelist_order() will set this to NODE or ZONE. |
| */ |
| static int current_zonelist_order = ZONELIST_ORDER_DEFAULT; |
| static char zonelist_order_name[3][8] = {"Default", "Node", "Zone"}; |
| |
| |
| #ifdef CONFIG_NUMA |
| /* The value user specified ....changed by config */ |
| static int user_zonelist_order = ZONELIST_ORDER_DEFAULT; |
| /* string for sysctl */ |
| #define NUMA_ZONELIST_ORDER_LEN 16 |
| char numa_zonelist_order[16] = "default"; |
| |
| /* |
| * interface for configure zonelist ordering. |
| * command line option "numa_zonelist_order" |
| * = "[dD]efault - default, automatic configuration. |
| * = "[nN]ode - order by node locality, then by zone within node |
| * = "[zZ]one - order by zone, then by locality within zone |
| */ |
| |
| static int __parse_numa_zonelist_order(char *s) |
| { |
| if (*s == 'd' || *s == 'D') { |
| user_zonelist_order = ZONELIST_ORDER_DEFAULT; |
| } else if (*s == 'n' || *s == 'N') { |
| user_zonelist_order = ZONELIST_ORDER_NODE; |
| } else if (*s == 'z' || *s == 'Z') { |
| user_zonelist_order = ZONELIST_ORDER_ZONE; |
| } else { |
| pr_warn("Ignoring invalid numa_zonelist_order value: %s\n", s); |
| return -EINVAL; |
| } |
| return 0; |
| } |
| |
| static __init int setup_numa_zonelist_order(char *s) |
| { |
| int ret; |
| |
| if (!s) |
| return 0; |
| |
| ret = __parse_numa_zonelist_order(s); |
| if (ret == 0) |
| strlcpy(numa_zonelist_order, s, NUMA_ZONELIST_ORDER_LEN); |
| |
| return ret; |
| } |
| early_param("numa_zonelist_order", setup_numa_zonelist_order); |
| |
| /* |
| * sysctl handler for numa_zonelist_order |
| */ |
| int numa_zonelist_order_handler(struct ctl_table *table, int write, |
| void __user *buffer, size_t *length, |
| loff_t *ppos) |
| { |
| char saved_string[NUMA_ZONELIST_ORDER_LEN]; |
| int ret; |
| static DEFINE_MUTEX(zl_order_mutex); |
| |
| mutex_lock(&zl_order_mutex); |
| if (write) { |
| if (strlen((char *)table->data) >= NUMA_ZONELIST_ORDER_LEN) { |
| ret = -EINVAL; |
| goto out; |
| } |
| strcpy(saved_string, (char *)table->data); |
| } |
| ret = proc_dostring(table, write, buffer, length, ppos); |
| if (ret) |
| goto out; |
| if (write) { |
| int oldval = user_zonelist_order; |
| |
| ret = __parse_numa_zonelist_order((char *)table->data); |
| if (ret) { |
| /* |
| * bogus value. restore saved string |
| */ |
| strncpy((char *)table->data, saved_string, |
| NUMA_ZONELIST_ORDER_LEN); |
| user_zonelist_order = oldval; |
| } else if (oldval != user_zonelist_order) { |
| mutex_lock(&zonelists_mutex); |
| build_all_zonelists(NULL, NULL); |
| mutex_unlock(&zonelists_mutex); |
| } |
| } |
| out: |
| mutex_unlock(&zl_order_mutex); |
| return ret; |
| } |
| |
| |
| #define MAX_NODE_LOAD (nr_online_nodes) |
| static int node_load[MAX_NUMNODES]; |
| |
| /** |
| * find_next_best_node - find the next node that should appear in a given node's fallback list |
| * @node: node whose fallback list we're appending |
| * @used_node_mask: nodemask_t of already used nodes |
| * |
| * We use a number of factors to determine which is the next node that should |
| * appear on a given node's fallback list. The node should not have appeared |
| * already in @node's fallback list, and it should be the next closest node |
| * according to the distance array (which contains arbitrary distance values |
| * from each node to each node in the system), and should also prefer nodes |
| * with no CPUs, since presumably they'll have very little allocation pressure |
| * on them otherwise. |
| * It returns -1 if no node is found. |
| */ |
| static int find_next_best_node(int node, nodemask_t *used_node_mask) |
| { |
| int n, val; |
| int min_val = INT_MAX; |
| int best_node = NUMA_NO_NODE; |
| const struct cpumask *tmp = cpumask_of_node(0); |
| |
| /* Use the local node if we haven't already */ |
| if (!node_isset(node, *used_node_mask)) { |
| node_set(node, *used_node_mask); |
| return node; |
| } |
| |
| for_each_node_state(n, N_MEMORY) { |
| |
| /* Don't want a node to appear more than once */ |
| if (node_isset(n, *used_node_mask)) |
| continue; |
| |
| /* Use the distance array to find the distance */ |
| val = node_distance(node, n); |
| |
| /* Penalize nodes under us ("prefer the next node") */ |
| val += (n < node); |
| |
| /* Give preference to headless and unused nodes */ |
| tmp = cpumask_of_node(n); |
| if (!cpumask_empty(tmp)) |
| val += PENALTY_FOR_NODE_WITH_CPUS; |
| |
| /* Slight preference for less loaded node */ |
| val *= (MAX_NODE_LOAD*MAX_NUMNODES); |
| val += node_load[n]; |
| |
| if (val < min_val) { |
| min_val = val; |
| best_node = n; |
| } |
| } |
| |
| if (best_node >= 0) |
| node_set(best_node, *used_node_mask); |
| |
| return best_node; |
| } |
| |
| |
| /* |
| * Build zonelists ordered by node and zones within node. |
| * This results in maximum locality--normal zone overflows into local |
| * DMA zone, if any--but risks exhausting DMA zone. |
| */ |
| static void build_zonelists_in_node_order(pg_data_t *pgdat, int node) |
| { |
| int j; |
| struct zonelist *zonelist; |
| |
| zonelist = &pgdat->node_zonelists[ZONELIST_FALLBACK]; |
| for (j = 0; zonelist->_zonerefs[j].zone != NULL; j++) |
| ; |
| j = build_zonelists_node(NODE_DATA(node), zonelist, j); |
| zonelist->_zonerefs[j].zone = NULL; |
| zonelist->_zonerefs[j].zone_idx = 0; |
| } |
| |
| /* |
| * Build gfp_thisnode zonelists |
| */ |
| static void build_thisnode_zonelists(pg_data_t *pgdat) |
| { |
| int j; |
| struct zonelist *zonelist; |
| |
| zonelist = &pgdat->node_zonelists[ZONELIST_NOFALLBACK]; |
| j = build_zonelists_node(pgdat, zonelist, 0); |
| zonelist->_zonerefs[j].zone = NULL; |
| zonelist->_zonerefs[j].zone_idx = 0; |
| } |
| |
| /* |
| * Build zonelists ordered by zone and nodes within zones. |
| * This results in conserving DMA zone[s] until all Normal memory is |
| * exhausted, but results in overflowing to remote node while memory |
| * may still exist in local DMA zone. |
| */ |
| static int node_order[MAX_NUMNODES]; |
| |
| static void build_zonelists_in_zone_order(pg_data_t *pgdat, int nr_nodes) |
| { |
| int pos, j, node; |
| int zone_type; /* needs to be signed */ |
| struct zone *z; |
| struct zonelist *zonelist; |
| |
| zonelist = &pgdat->node_zonelists[ZONELIST_FALLBACK]; |
| pos = 0; |
| for (zone_type = MAX_NR_ZONES - 1; zone_type >= 0; zone_type--) { |
| for (j = 0; j < nr_nodes; j++) { |
| node = node_order[j]; |
| z = &NODE_DATA(node)->node_zones[zone_type]; |
| if (managed_zone(z)) { |
| zoneref_set_zone(z, |
| &zonelist->_zonerefs[pos++]); |
| check_highest_zone(zone_type); |
| } |
| } |
| } |
| zonelist->_zonerefs[pos].zone = NULL; |
| zonelist->_zonerefs[pos].zone_idx = 0; |
| } |
| |
| #if defined(CONFIG_64BIT) |
| /* |
| * Devices that require DMA32/DMA are relatively rare and do not justify a |
| * penalty to every machine in case the specialised case applies. Default |
| * to Node-ordering on 64-bit NUMA machines |
| */ |
| static int default_zonelist_order(void) |
| { |
| return ZONELIST_ORDER_NODE; |
| } |
| #else |
| /* |
| * On 32-bit, the Normal zone needs to be preserved for allocations accessible |
| * by the kernel. If processes running on node 0 deplete the low memory zone |
| * then reclaim will occur more frequency increasing stalls and potentially |
| * be easier to OOM if a large percentage of the zone is under writeback or |
| * dirty. The problem is significantly worse if CONFIG_HIGHPTE is not set. |
| * Hence, default to zone ordering on 32-bit. |
| */ |
| static int default_zonelist_order(void) |
| { |
| return ZONELIST_ORDER_ZONE; |
| } |
| #endif /* CONFIG_64BIT */ |
| |
| static void set_zonelist_order(void) |
| { |
| if (user_zonelist_order == ZONELIST_ORDER_DEFAULT) |
| current_zonelist_order = default_zonelist_order(); |
| else |
| current_zonelist_order = user_zonelist_order; |
| } |
| |
| static void build_zonelists(pg_data_t *pgdat) |
| { |
| int i, node, load; |
| nodemask_t used_mask; |
| int local_node, prev_node; |
| struct zonelist *zonelist; |
| unsigned int order = current_zonelist_order; |
| |
| /* initialize zonelists */ |
| for (i = 0; i < MAX_ZONELISTS; i++) { |
| zonelist = pgdat->node_zonelists + i; |
| zonelist->_zonerefs[0].zone = NULL; |
| zonelist->_zonerefs[0].zone_idx = 0; |
| } |
| |
| /* NUMA-aware ordering of nodes */ |
| local_node = pgdat->node_id; |
| load = nr_online_nodes; |
| prev_node = local_node; |
| nodes_clear(used_mask); |
| |
| memset(node_order, 0, sizeof(node_order)); |
| i = 0; |
| |
| while ((node = find_next_best_node(local_node, &used_mask)) >= 0) { |
| /* |
| * We don't want to pressure a particular node. |
| * So adding penalty to the first node in same |
| * distance group to make it round-robin. |
| */ |
| if (node_distance(local_node, node) != |
| node_distance(local_node, prev_node)) |
| node_load[node] = load; |
| |
| prev_node = node; |
| load--; |
| if (order == ZONELIST_ORDER_NODE) |
| build_zonelists_in_node_order(pgdat, node); |
| else |
| node_order[i++] = node; /* remember order */ |
| } |
| |
| if (order == ZONELIST_ORDER_ZONE) { |
| /* calculate node order -- i.e., DMA last! */ |
| build_zonelists_in_zone_order(pgdat, i); |
| } |
| |
| build_thisnode_zonelists(pgdat); |
| } |
| |
| #ifdef CONFIG_HAVE_MEMORYLESS_NODES |
| /* |
| * Return node id of node used for "local" allocations. |
| * I.e., first node id of first zone in arg node's generic zonelist. |
| * Used for initializing percpu 'numa_mem', which is used primarily |
| * for kernel allocations, so use GFP_KERNEL flags to locate zonelist. |
| */ |
| int local_memory_node(int node) |
| { |
| struct zoneref *z; |
| |
| z = first_zones_zonelist(node_zonelist(node, GFP_KERNEL), |
| gfp_zone(GFP_KERNEL), |
| NULL); |
| return z->zone->node; |
| } |
| #endif |
| |
| static void setup_min_unmapped_ratio(void); |
| static void setup_min_slab_ratio(void); |
| #else /* CONFIG_NUMA */ |
| |
| static void set_zonelist_order(void) |
| { |
| current_zonelist_order = ZONELIST_ORDER_ZONE; |
| } |
| |
| static void build_zonelists(pg_data_t *pgdat) |
| { |
| int node, local_node; |
| enum zone_type j; |
| struct zonelist *zonelist; |
| |
| local_node = pgdat->node_id; |
| |
| zonelist = &pgdat->node_zonelists[ZONELIST_FALLBACK]; |
| j = build_zonelists_node(pgdat, zonelist, 0); |
| |
| /* |
| * Now we build the zonelist so that it contains the zones |
| * of all the other nodes. |
| * We don't want to pressure a particular node, so when |
| * building the zones for node N, we make sure that the |
| * zones coming right after the local ones are those from |
| * node N+1 (modulo N) |
| */ |
| for (node = local_node + 1; node < MAX_NUMNODES; node++) { |
| if (!node_online(node)) |
| continue; |
| j = build_zonelists_node(NODE_DATA(node), zonelist, j); |
| } |
| for (node = 0; node < local_node; node++) { |
| if (!node_online(node)) |
| continue; |
| j = build_zonelists_node(NODE_DATA(node), zonelist, j); |
| } |
| |
| zonelist->_zonerefs[j].zone = NULL; |
| zonelist->_zonerefs[j].zone_idx = 0; |
| } |
| |
| #endif /* CONFIG_NUMA */ |
| |
| /* |
| * Boot pageset table. One per cpu which is going to be used for all |
| * zones and all nodes. The parameters will be set in such a way |
| * that an item put on a list will immediately be handed over to |
| * the buddy list. This is safe since pageset manipulation is done |
| * with interrupts disabled. |
| * |
| * The boot_pagesets must be kept even after bootup is complete for |
| * unused processors and/or zones. They do play a role for bootstrapping |
| * hotplugged processors. |
| * |
| * zoneinfo_show() and maybe other functions do |
| * not check if the processor is online before following the pageset pointer. |
| * Other parts of the kernel may not check if the zone is available. |
| */ |
| static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch); |
| static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset); |
| static void setup_zone_pageset(struct zone *zone); |
| |
| /* |
| * Global mutex to protect against size modification of zonelists |
| * as well as to serialize pageset setup for the new populated zone. |
| */ |
| DEFINE_MUTEX(zonelists_mutex); |
| |
| /* return values int ....just for stop_machine() */ |
| static int __build_all_zonelists(void *data) |
| { |
| int nid; |
| int cpu; |
| pg_data_t *self = data; |
| |
| #ifdef CONFIG_NUMA |
| memset(node_load, 0, sizeof(node_load)); |
| #endif |
| |
| if (self && !node_online(self->node_id)) { |
| build_zonelists(self); |
| } |
| |
| for_each_online_node(nid) { |
| pg_data_t *pgdat = NODE_DATA(nid); |
| |
| build_zonelists(pgdat); |
| } |
| |
| /* |
| * Initialize the boot_pagesets that are going to be used |
| * for bootstrapping processors. The real pagesets for |
| * each zone will be allocated later when the per cpu |
| * allocator is available. |
| * |
| * boot_pagesets are used also for bootstrapping offline |
| * cpus if the system is already booted because the pagesets |
| * are needed to initialize allocators on a specific cpu too. |
| * F.e. the percpu allocator needs the page allocator which |
| * needs the percpu allocator in order to allocate its pagesets |
| * (a chicken-egg dilemma). |
| */ |
| for_each_possible_cpu(cpu) { |
| setup_pageset(&per_cpu(boot_pageset, cpu), 0); |
| |
| #ifdef CONFIG_HAVE_MEMORYLESS_NODES |
| /* |
| * We now know the "local memory node" for each node-- |
| * i.e., the node of the first zone in the generic zonelist. |
| * Set up numa_mem percpu variable for on-line cpus. During |
| * boot, only the boot cpu should be on-line; we'll init the |
| * secondary cpus' numa_mem as they come on-line. During |
| * node/memory hotplug, we'll fixup all on-line cpus. |
| */ |
| if (cpu_online(cpu)) |
| set_cpu_numa_mem(cpu, local_memory_node(cpu_to_node(cpu))); |
| #endif |
| } |
| |
| return 0; |
| } |
| |
| static noinline void __init |
| build_all_zonelists_init(void) |
| { |
| __build_all_zonelists(NULL); |
| mminit_verify_zonelist(); |
| cpuset_init_current_mems_allowed(); |
| } |
| |
| /* |
| * Called with zonelists_mutex held always |
| * unless system_state == SYSTEM_BOOTING. |
| * |
| * __ref due to (1) call of __meminit annotated setup_zone_pageset |
| * [we're only called with non-NULL zone through __meminit paths] and |
| * (2) call of __init annotated helper build_all_zonelists_init |
| * [protected by SYSTEM_BOOTING]. |
| */ |
| void __ref build_all_zonelists(pg_data_t *pgdat, struct zone *zone) |
| { |
| set_zonelist_order(); |
| |
| if (system_state == SYSTEM_BOOTING) { |
| build_all_zonelists_init(); |
| } else { |
| #ifdef CONFIG_MEMORY_HOTPLUG |
| if (zone) |
| setup_zone_pageset(zone); |
| #endif |
| /* we have to stop all cpus to guarantee there is no user |
| of zonelist */ |
| stop_machine(__build_all_zonelists, pgdat, NULL); |
| /* cpuset refresh routine should be here */ |
| } |
| vm_total_pages = nr_free_pagecache_pages(); |
| /* |
| * Disable grouping by mobility if the number of pages in the |
| * system is too low to allow the mechanism to work. It would be |
| * more accurate, but expensive to check per-zone. This check is |
| * made on memory-hotadd so a system can start with mobility |
| * disabled and enable it later |
| */ |
| if (vm_total_pages < (pageblock_nr_pages * MIGRATE_TYPES)) |
| page_group_by_mobility_disabled = 1; |
| else |
| page_group_by_mobility_disabled = 0; |
| |
| pr_info("Built %i zonelists in %s order, mobility grouping %s. Total pages: %ld\n", |
| nr_online_nodes, |
| zonelist_order_name[current_zonelist_order], |
| page_group_by_mobility_disabled ? "off" : "on", |
| vm_total_pages); |
| #ifdef CONFIG_NUMA |
| pr_info("Policy zone: %s\n", zone_names[policy_zone]); |
| #endif |
| } |
| |
| /* |
| * Initially all pages are reserved - free ones are freed |
| * up by free_all_bootmem() once the early boot process is |
| * done. Non-atomic initialization, single-pass. |
| */ |
| void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, |
| unsigned long start_pfn, enum memmap_context context) |
| { |
| struct vmem_altmap *altmap = to_vmem_altmap(__pfn_to_phys(start_pfn)); |
| unsigned long end_pfn = start_pfn + size; |
| pg_data_t *pgdat = NODE_DATA(nid); |
| unsigned long pfn; |
| unsigned long nr_initialised = 0; |
| #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP |
| struct memblock_region *r = NULL, *tmp; |
| #endif |
| |
| if (highest_memmap_pfn < end_pfn - 1) |
| highest_memmap_pfn = end_pfn - 1; |
| |
| /* |
| * Honor reservation requested by the driver for this ZONE_DEVICE |
| * memory |
| */ |
| if (altmap && start_pfn == altmap->base_pfn) |
| start_pfn += altmap->reserve; |
| |
| for (pfn = start_pfn; pfn < end_pfn; pfn++) { |
| /* |
| * There can be holes in boot-time mem_map[]s handed to this |
| * function. They do not exist on hotplugged memory. |
| */ |
| if (context != MEMMAP_EARLY) |
| goto not_early; |
| |
| if (!early_pfn_valid(pfn)) |
| continue; |
| if (!early_pfn_in_nid(pfn, nid)) |
| continue; |
| if (!update_defer_init(pgdat, pfn, end_pfn, &nr_initialised)) |
| break; |
| |
| #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP |
| /* |
| * Check given memblock attribute by firmware which can affect |
| * kernel memory layout. If zone==ZONE_MOVABLE but memory is |
| * mirrored, it's an overlapped memmap init. skip it. |
| */ |
| if (mirrored_kernelcore && zone == ZONE_MOVABLE) { |
| if (!r || pfn >= memblock_region_memory_end_pfn(r)) { |
| for_each_memblock(memory, tmp) |
| if (pfn < memblock_region_memory_end_pfn(tmp)) |
| break; |
| r = tmp; |
| } |
| if (pfn >= memblock_region_memory_base_pfn(r) && |
| memblock_is_mirror(r)) { |
| /* already initialized as NORMAL */ |
| pfn = memblock_region_memory_end_pfn(r); |
| continue; |
| } |
| } |
| #endif |
| |
| not_early: |
| /* |
| * Mark the block movable so that blocks are reserved for |
| * movable at startup. This will force kernel allocations |
| * to reserve their blocks rather than leaking throughout |
| * the address space during boot when many long-lived |
| * kernel allocations are made. |
| * |
| * bitmap is created for zone's valid pfn range. but memmap |
| * can be created for invalid pages (for alignment) |
| * check here not to call set_pageblock_migratetype() against |
| * pfn out of zone. |
| */ |
| if (!(pfn & (pageblock_nr_pages - 1))) { |
| struct page *page = pfn_to_page(pfn); |
| |
| __init_single_page(page, pfn, zone, nid); |
| set_pageblock_migratetype(page, MIGRATE_MOVABLE); |
| } else { |
| __init_single_pfn(pfn, zone, nid); |
| } |
| } |
| } |
| |
| static void __meminit zone_init_free_lists(struct zone *zone) |
| { |
| unsigned int order, t; |
| for_each_migratetype_order(order, t) { |
| INIT_LIST_HEAD(&zone->free_area[order].free_list[t]); |
| zone->free_area[order].nr_free = 0; |
| } |
| } |
| |
| #ifndef __HAVE_ARCH_MEMMAP_INIT |
| #define memmap_init(size, nid, zone, start_pfn) \ |
| memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY) |
| #endif |
| |
| static int zone_batchsize(struct zone *zone) |
| { |
| #ifdef CONFIG_MMU |
| int batch; |
| |
| /* |
| * The per-cpu-pages pools are set to around 1000th of the |
| * size of the zone. But no more than 1/2 of a meg. |
| * |
| * OK, so we don't know how big the cache is. So guess. |
| */ |
| batch = zone->managed_pages / 1024; |
| if (batch * PAGE_SIZE > 512 * 1024) |
| batch = (512 * 1024) / PAGE_SIZE; |
| batch /= 4; /* We effectively *= 4 below */ |
| if (batch < 1) |
| batch = 1; |
| |
| /* |
| * Clamp the batch to a 2^n - 1 value. Having a power |
| * of 2 value was found to be more likely to have |
| * suboptimal cache aliasing properties in some cases. |
| * |
| * For example if 2 tasks are alternately allocating |
| * batches of pages, one task can end up with a lot |
| * of pages of one half of the possible page colors |
| * and the other with pages of the other colors. |
| */ |
| batch = rounddown_pow_of_two(batch + batch/2) - 1; |
| |
| return batch; |
| |
| #else |
| /* The deferral and batching of frees should be suppressed under NOMMU |
| * conditions. |
| * |
| * The problem is that NOMMU needs to be able to allocate large chunks |
| * of contiguous memory as there's no hardware page translation to |
| * assemble apparent contiguous memory from discontiguous pages. |
| * |
| * Queueing large contiguous runs of pages for batching, however, |
| * causes the pages to actually be freed in smaller chunks. As there |
| * can be a significant delay between the individual batches being |
| * recycled, this leads to the once large chunks of space being |
| * fragmented and becoming unavailable for high-order allocations. |
| */ |
| return 0; |
| #endif |
| } |
| |
| /* |
| * pcp->high and pcp->batch values are related and dependent on one another: |
| * ->batch must never be higher then ->high. |
| * The following function updates them in a safe manner without read side |
| * locking. |
| * |
| * Any new users of pcp->batch and pcp->high should ensure they can cope with |
| * those fields changing asynchronously (acording the the above rule). |
| * |
| * mutex_is_locked(&pcp_batch_high_lock) required when calling this function |
| * outside of boot time (or some other assurance that no concurrent updaters |
| * exist). |
| */ |
| static void pageset_update(struct per_cpu_pages *pcp, unsigned long high, |
| unsigned long batch) |
| { |
| /* start with a fail safe value for batch */ |
| pcp->batch = 1; |
| smp_wmb(); |
| |
| /* Update high, then batch, in order */ |
| pcp->high = high; |
| smp_wmb(); |
| |
| pcp->batch = batch; |
| } |
| |
| /* a companion to pageset_set_high() */ |
| static void pageset_set_batch(struct per_cpu_pageset *p, unsigned long batch) |
| { |
| pageset_update(&p->pcp, 6 * batch, max(1UL, 1 * batch)); |
| } |
| |
| static void pageset_init(struct per_cpu_pageset *p) |
| { |
| struct per_cpu_pages *pcp; |
| int migratetype; |
| |
| memset(p, 0, sizeof(*p)); |
| |
| pcp = &p->pcp; |
| pcp->count = 0; |
| for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++) |
| INIT_LIST_HEAD(&pcp->lists[migratetype]); |
| } |
| |
| static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch) |
| { |
| pageset_init(p); |
| pageset_set_batch(p, batch); |
| } |
| |
| /* |
| * pageset_set_high() sets the high water mark for hot per_cpu_pagelist |
| * to the value high for the pageset p. |
| */ |
| static void pageset_set_high(struct per_cpu_pageset *p, |
| unsigned long high) |
| { |
| unsigned long batch = max(1UL, high / 4); |
| if ((high / 4) > (PAGE_SHIFT * 8)) |
| batch = PAGE_SHIFT * 8; |
| |
| pageset_update(&p->pcp, high, batch); |
| } |
| |
| static void pageset_set_high_and_batch(struct zone *zone, |
| struct per_cpu_pageset *pcp) |
| { |
| if (percpu_pagelist_fraction) |
| pageset_set_high(pcp, |
| (zone->managed_pages / |
| percpu_pagelist_fraction)); |
| else |
| pageset_set_batch(pcp, zone_batchsize(zone)); |
| } |
| |
| static void __meminit zone_pageset_init(struct zone *zone, int cpu) |
| { |
| struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu); |
| |
| pageset_init(pcp); |
| pageset_set_high_and_batch(zone, pcp); |
| } |
| |
| static void __meminit setup_zone_pageset(struct zone *zone) |
| { |
| int cpu; |
| zone->pageset = alloc_percpu(struct per_cpu_pageset); |
| for_each_possible_cpu(cpu) |
| zone_pageset_init(zone, cpu); |
| } |
| |
| /* |
| * Allocate per cpu pagesets and initialize them. |
| * Before this call only boot pagesets were available. |
| */ |
| void __init setup_per_cpu_pageset(void) |
| { |
| struct pglist_data *pgdat; |
| struct zone *zone; |
| |
| for_each_populated_zone(zone) |
| setup_zone_pageset(zone); |
| |
| for_each_online_pgdat(pgdat) |
| pgdat->per_cpu_nodestats = |
| alloc_percpu(struct per_cpu_nodestat); |
| } |
| |
| static __meminit void zone_pcp_init(struct zone *zone) |
| { |
| /* |
| * per cpu subsystem is not up at this point. The following code |
| * relies on the ability of the linker to provide the |
| * offset of a (static) per cpu variable into the per cpu area. |
| */ |
| zone->pageset = &boot_pageset; |
| |
| if (populated_zone(zone)) |
| printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%u\n", |
| zone->name, zone->present_pages, |
| zone_batchsize(zone)); |
| } |
| |
| int __meminit init_currently_empty_zone(struct zone *zone, |
| unsigned long zone_start_pfn, |
| unsigned long size) |
| { |
| struct pglist_data *pgdat = zone->zone_pgdat; |
| |
| pgdat->nr_zones = zone_idx(zone) + 1; |
| |
| zone->zone_start_pfn = zone_start_pfn; |
| |
| mminit_dprintk(MMINIT_TRACE, "memmap_init", |
| "Initialising map node %d zone %lu pfns %lu -> %lu\n", |
| pgdat->node_id, |
| (unsigned long)zone_idx(zone), |
| zone_start_pfn, (zone_start_pfn + size)); |
| |
| zone_init_free_lists(zone); |
| zone->initialized = 1; |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP |
| #ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID |
| |
| /* |
| * Required by SPARSEMEM. Given a PFN, return what node the PFN is on. |
| */ |
| int __meminit __early_pfn_to_nid(unsigned long pfn, |
| struct mminit_pfnnid_cache *state) |
| { |
| unsigned long start_pfn, end_pfn; |
| int nid; |
| |
| if (state->last_start <= pfn && pfn < state->last_end) |
| return state->last_nid; |
| |
| nid = memblock_search_pfn_nid(pfn, &start_pfn, &end_pfn); |
| if (nid != -1) { |
| state->last_start = start_pfn; |
| state->last_end = end_pfn; |
| state->last_nid = nid; |
| } |
| |
| return nid; |
| } |
| #endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */ |
| |
| /** |
| * free_bootmem_with_active_regions - Call memblock_free_early_nid for each active range |
| * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed. |
| * @max_low_pfn: The highest PFN that will be passed to memblock_free_early_nid |
| * |
| * If an architecture guarantees that all ranges registered contain no holes |
| * and may be freed, this this function may be used instead of calling |
| * memblock_free_early_nid() manually. |
| */ |
| void __init free_bootmem_with_active_regions(int nid, unsigned long max_low_pfn) |
| { |
| unsigned long start_pfn, end_pfn; |
| int i, this_nid; |
| |
| for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, &this_nid) { |
| start_pfn = min(start_pfn, max_low_pfn); |
| end_pfn = min(end_pfn, max_low_pfn); |
| |
| if (start_pfn < end_pfn) |
| memblock_free_early_nid(PFN_PHYS(start_pfn), |
| (end_pfn - start_pfn) << PAGE_SHIFT, |
| this_nid); |
| } |
| } |
| |
| /** |
| * sparse_memory_present_with_active_regions - Call memory_present for each active range |
| * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used. |
| * |
| * If an architecture guarantees that all ranges registered contain no holes and may |
| * be freed, this function may be used instead of calling memory_present() manually. |
| */ |
| void __init sparse_memory_present_with_active_regions(int nid) |
| { |
| unsigned long start_pfn, end_pfn; |
| int i, this_nid; |
| |
| for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, &this_nid) |
| memory_present(this_nid, start_pfn, end_pfn); |
| } |
| |
| /** |
| * get_pfn_range_for_nid - Return the start and end page frames for a node |
| * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned. |
| * @start_pfn: Passed by reference. On return, it will have the node start_pfn. |
| * @end_pfn: Passed by reference. On return, it will have the node end_pfn. |
| * |
| * It returns the start and end page frame of a node based on information |
| * provided by memblock_set_node(). If called for a node |
| * with no available memory, a warning is printed and the start and end |
| * PFNs will be 0. |
| */ |
| void __meminit get_pfn_range_for_nid(unsigned int nid, |
| unsigned long *start_pfn, unsigned long *end_pfn) |
| { |
| unsigned long this_start_pfn, this_end_pfn; |
| int i; |
| |
| *start_pfn = -1UL; |
| *end_pfn = 0; |
| |
| for_each_mem_pfn_range(i, nid, &this_start_pfn, &this_end_pfn, NULL) { |
| *start_pfn = min(*start_pfn, this_start_pfn); |
| *end_pfn = max(*end_pfn, this_end_pfn); |
| } |
| |
| if (*start_pfn == -1UL) |
| *start_pfn = 0; |
| } |
| |
| /* |
| * This finds a zone that can be used for ZONE_MOVABLE pages. The |
| * assumption is made that zones within a node are ordered in monotonic |
| * increasing memory addresses so that the "highest" populated zone is used |
| */ |
| static void __init find_usable_zone_for_movable(void) |
| { |
| int zone_index; |
| for (zone_index = MAX_NR_ZONES - 1; zone_index >= 0; zone_index--) { |
| if (zone_index == ZONE_MOVABLE) |
| continue; |
| |
| if (arch_zone_highest_possible_pfn[zone_index] > |
| arch_zone_lowest_possible_pfn[zone_index]) |
| break; |
| } |
| |
| VM_BUG_ON(zone_index == -1); |
| movable_zone = zone_index; |
| } |
| |
| /* |
| * The zone ranges provided by the architecture do not include ZONE_MOVABLE |
| * because it is sized independent of architecture. Unlike the other zones, |
| * the starting point for ZONE_MOVABLE is not fixed. It may be different |
| * in each node depending on the size of each node and how evenly kernelcore |
| * is distributed. This helper function adjusts the zone ranges |
| * provided by the architecture for a given node by using the end of the |
| * highest usable zone for ZONE_MOVABLE. This preserves the assumption that |
| * zones within a node are in order of monotonic increases memory addresses |
| */ |
| static void __meminit adjust_zone_range_for_zone_movable(int nid, |
| unsigned long zone_type, |
| unsigned long node_start_pfn, |
| unsigned long node_end_pfn, |
| unsigned long *zone_start_pfn, |
| unsigned long *zone_end_pfn) |
| { |
| /* Only adjust if ZONE_MOVABLE is on this node */ |
| if (zone_movable_pfn[nid]) { |
| /* Size ZONE_MOVABLE */ |
| if (zone_type == ZONE_MOVABLE) { |
| *zone_start_pfn = zone_movable_pfn[nid]; |
| *zone_end_pfn = min(node_end_pfn, |
| arch_zone_highest_possible_pfn[movable_zone]); |
| |
| /* Adjust for ZONE_MOVABLE starting within this range */ |
| } else if (!mirrored_kernelcore && |
| *zone_start_pfn < zone_movable_pfn[nid] && |
| *zone_end_pfn > zone_movable_pfn[nid]) { |
| *zone_end_pfn = zone_movable_pfn[nid]; |
| |
| /* Check if this whole range is within ZONE_MOVABLE */ |
| } else if (*zone_start_pfn >= zone_movable_pfn[nid]) |
| *zone_start_pfn = *zone_end_pfn; |
| } |
| } |
| |
| /* |
| * Return the number of pages a zone spans in a node, including holes |
| * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node() |
| */ |
| static unsigned long __meminit zone_spanned_pages_in_node(int nid, |
| unsigned long zone_type, |
| unsigned long node_start_pfn, |
| unsigned long node_end_pfn, |
| unsigned long *zone_start_pfn, |
| unsigned long *zone_end_pfn, |
| unsigned long *ignored) |
| { |
| /* When hotadd a new node from cpu_up(), the node should be empty */ |
| if (!node_start_pfn && !node_end_pfn) |
| return 0; |
| |
| /* Get the start and end of the zone */ |
| *zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type]; |
| *zone_end_pfn = arch_zone_highest_possible_pfn[zone_type]; |
| adjust_zone_range_for_zone_movable(nid, zone_type, |
| node_start_pfn, node_end_pfn, |
| zone_start_pfn, zone_end_pfn); |
| |
| /* Check that this node has pages within the zone's required range */ |
| if (*zone_end_pfn < node_start_pfn || *zone_start_pfn > node_end_pfn) |
| return 0; |
| |
| /* Move the zone boundaries inside the node if necessary */ |
| *zone_end_pfn = min(*zone_end_pfn, node_end_pfn); |
| *zone_start_pfn = max(*zone_start_pfn, node_start_pfn); |
| |
| /* Return the spanned pages */ |
| return *zone_end_pfn - *zone_start_pfn; |
| } |
| |
| /* |
| * Return the number of holes in a range on a node. If nid is MAX_NUMNODES, |
| * then all holes in the requested range will be accounted for. |
| */ |
| unsigned long __meminit __absent_pages_in_range(int nid, |
| unsigned long range_start_pfn, |
| unsigned long range_end_pfn) |
| { |
| unsigned long nr_absent = range_end_pfn - range_start_pfn; |
| unsigned long start_pfn, end_pfn; |
| int i; |
| |
| for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) { |
| start_pfn = clamp(start_pfn, range_start_pfn, range_end_pfn); |
| end_pfn = clamp(end_pfn, range_start_pfn, range_end_pfn); |
| nr_absent -= end_pfn - start_pfn; |
| } |
| return nr_absent; |
| } |
| |
| /** |
| * absent_pages_in_range - Return number of page frames in holes within a range |
| * @start_pfn: The start PFN to start searching for holes |
| * @end_pfn: The end PFN to stop searching for holes |
| * |
| * It returns the number of pages frames in memory holes within a range. |
| */ |
| unsigned long __init absent_pages_in_range(unsigned long start_pfn, |
| unsigned long end_pfn) |
| { |
| return __absent_pages_in_range(MAX_NUMNODES, start_pfn, end_pfn); |
| } |
| |
| /* Return the number of page frames in holes in a zone on a node */ |
| static unsigned long __meminit zone_absent_pages_in_node(int nid, |
| unsigned long zone_type, |
| unsigned long node_start_pfn, |
| unsigned long node_end_pfn, |
| unsigned long *ignored) |
| { |
| unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type]; |
| unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type]; |
| unsigned long zone_start_pfn, zone_end_pfn; |
| unsigned long nr_absent; |
| |
| /* When hotadd a new node from cpu_up(), the node should be empty */ |
| if (!node_start_pfn && !node_end_pfn) |
| return 0; |
| |
| zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high); |
| zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high); |
| |
| adjust_zone_range_for_zone_movable(nid, zone_type, |
| node_start_pfn, node_end_pfn, |
| &zone_start_pfn, &zone_end_pfn); |
| nr_absent = __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn); |
| |
| /* |
| * ZONE_MOVABLE handling. |
| * Treat pages to be ZONE_MOVABLE in ZONE_NORMAL as absent pages |
| * and vice versa. |
| */ |
| if (mirrored_kernelcore && zone_movable_pfn[nid]) { |
| unsigned long start_pfn, end_pfn; |
| struct memblock_region *r; |
| |
| for_each_memblock(memory, r) { |
| start_pfn = clamp(memblock_region_memory_base_pfn(r), |
| zone_start_pfn, zone_end_pfn); |
| end_pfn = clamp(memblock_region_memory_end_pfn(r), |
| zone_start_pfn, zone_end_pfn); |
| |
| if (zone_type == ZONE_MOVABLE && |
| memblock_is_mirror(r)) |
| nr_absent += end_pfn - start_pfn; |
| |
| if (zone_type == ZONE_NORMAL && |
| !memblock_is_mirror(r)) |
| nr_absent += end_pfn - start_pfn; |
| } |
| } |
| |
| return nr_absent; |
| } |
| |
| #else /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ |
| static inline unsigned long __meminit zone_spanned_pages_in_node(int nid, |
| unsigned long zone_type, |
| unsigned long node_start_pfn, |
| unsigned long node_end_pfn, |
| unsigned long *zone_start_pfn, |
| unsigned long *zone_end_pfn, |
| unsigned long *zones_size) |
| { |
| unsigned int zone; |
| |
| *zone_start_pfn = node_start_pfn; |
| for (zone = 0; zone < zone_type; zone++) |
| *zone_start_pfn += zones_size[zone]; |
| |
| *zone_end_pfn = *zone_start_pfn + zones_size[zone_type]; |
| |
| return zones_size[zone_type]; |
| } |
| |
| static inline unsigned long __meminit zone_absent_pages_in_node(int nid, |
| unsigned long zone_type, |
| unsigned long node_start_pfn, |
| unsigned long node_end_pfn, |
| unsigned long *zholes_size) |
| { |
| if (!zholes_size) |
| return 0; |
| |
| return zholes_size[zone_type]; |
| } |
| |
| #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ |
| |
| static void __meminit calculate_node_totalpages(struct pglist_data *pgdat, |
| unsigned long node_start_pfn, |
| unsigned long node_end_pfn, |
| unsigned long *zones_size, |
| unsigned long *zholes_size) |
| { |
| unsigned long realtotalpages = 0, totalpages = 0; |
| enum zone_type i; |
| |
| for (i = 0; i < MAX_NR_ZONES; i++) { |
| struct zone *zone = pgdat->node_zones + i; |
| unsigned long zone_start_pfn, zone_end_pfn; |
| unsigned long size, real_size; |
| |
| size = zone_spanned_pages_in_node(pgdat->node_id, i, |
| node_start_pfn, |
| node_end_pfn, |
| &zone_start_pfn, |
| &zone_end_pfn, |
| zones_size); |
| real_size = size - zone_absent_pages_in_node(pgdat->node_id, i, |
| node_start_pfn, node_end_pfn, |
| zholes_size); |
| if (size) |
| zone->zone_start_pfn = zone_start_pfn; |
| else |
| zone->zone_start_pfn = 0; |
| zone->spanned_pages = size; |
| zone->present_pages = real_size; |
| |
| totalpages += size; |
| realtotalpages += real_size; |
| } |
| |
| pgdat->node_spanned_pages = totalpages; |
| pgdat->node_present_pages = realtotalpages; |
| printk(KERN_DEBUG "On node %d totalpages: %lu\n", pgdat->node_id, |
| realtotalpages); |
| } |
| |
| #ifndef CONFIG_SPARSEMEM |
| /* |
| * Calculate the size of the zone->blockflags rounded to an unsigned long |
| * Start by making sure zonesize is a multiple of pageblock_order by rounding |
| * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally |
| * round what is now in bits to nearest long in bits, then return it in |
| * bytes. |
| */ |
| static unsigned long __init usemap_size(unsigned long zone_start_pfn, unsigned long zonesize) |
| { |
| unsigned long usemapsize; |
| |
| zonesize += zone_start_pfn & (pageblock_nr_pages-1); |
| usemapsize = roundup(zonesize, pageblock_nr_pages); |
| usemapsize = usemapsize >> pageblock_order; |
| usemapsize *= NR_PAGEBLOCK_BITS; |
| usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long)); |
| |
| return usemapsize / 8; |
| } |
| |
| static void __init setup_usemap(struct pglist_data *pgdat, |
| struct zone *zone, |
| unsigned long zone_start_pfn, |
| unsigned long zonesize) |
| { |
| unsigned long usemapsize = usemap_size(zone_start_pfn, zonesize); |
| zone->pageblock_flags = NULL; |
| if (usemapsize) |
| zone->pageblock_flags = |
| memblock_virt_alloc_node_nopanic(usemapsize, |
| pgdat->node_id); |
| } |
| #else |
| static inline void setup_usemap(struct pglist_data *pgdat, struct zone *zone, |
| unsigned long zone_start_pfn, unsigned long zonesize) {} |
| #endif /* CONFIG_SPARSEMEM */ |
| |
| #ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE |
| |
| /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */ |
| void __paginginit set_pageblock_order(void) |
| { |
| unsigned int order; |
| |
| /* Check that pageblock_nr_pages has not already been setup */ |
| if (pageblock_order) |
| return; |
| |
| if (HPAGE_SHIFT > PAGE_SHIFT) |
| order = HUGETLB_PAGE_ORDER; |
| else |
| order = MAX_ORDER - 1; |
| |
| /* |
| * Assume the largest contiguous order of interest is a huge page. |
| * This value may be variable depending on boot parameters on IA64 and |
| * powerpc. |
| */ |
| pageblock_order = order; |
| } |
| #else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ |
| |
| /* |
| * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order() |
| * is unused as pageblock_order is set at compile-time. See |
| * include/linux/pageblock-flags.h for the values of pageblock_order based on |
| * the kernel config |
| */ |
| void __paginginit set_pageblock_order(void) |
| { |
| } |
| |
| #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ |
| |
| static unsigned long __paginginit calc_memmap_size(unsigned long spanned_pages, |
| unsigned long present_pages) |
| { |
| unsigned long pages = spanned_pages; |
| |
| /* |
| * Provide a more accurate estimation if there are holes within |
| * the zone and SPARSEMEM is in use. If there are holes within the |
| * zone, each populated memory region may cost us one or two extra |
| * memmap pages due to alignment because memmap pages for each |
| * populated regions may not naturally algined on page boundary. |
| * So the (present_pages >> 4) heuristic is a tradeoff for that. |
| */ |
| if (spanned_pages > present_pages + (present_pages >> 4) && |
| IS_ENABLED(CONFIG_SPARSEMEM)) |
| pages = present_pages; |
| |
| return PAGE_ALIGN(pages * sizeof(struct page)) >> PAGE_SHIFT; |
| } |
| |
| /* |
| * Set up the zone data structures: |
| * - mark all pages reserved |
| * - mark all memory queues empty |
| * - clear the memory bitmaps |
| * |
| * NOTE: pgdat should get zeroed by caller. |
| */ |
| static void __paginginit free_area_init_core(struct pglist_data *pgdat) |
| { |
| enum zone_type j; |
| int nid = pgdat->node_id; |
| 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 |
| #ifdef CONFIG_TRANSPARENT_HUGEPAGE |
| spin_lock_init(&pgdat->split_queue_lock); |
| INIT_LIST_HEAD(&pgdat->split_queue); |
| pgdat->split_queue_len = 0; |
| #endif |
| init_waitqueue_head(&pgdat->kswapd_wait); |
| init_waitqueue_head(&pgdat->pfmemalloc_wait); |
| #ifdef CONFIG_COMPACTION |
| init_waitqueue_head(&pgdat->kcompactd_wait); |
| #endif |
| pgdat_page_ext_init(pgdat); |
| spin_lock_init(&pgdat->lru_lock); |
| lruvec_init(node_lruvec(pgdat)); |
| |
| for (j = 0; j < MAX_NR_ZONES; j++) { |
| struct zone *zone = pgdat->node_zones + j; |
| unsigned long size, realsize, freesize, memmap_pages; |
| unsigned long zone_start_pfn = zone->zone_start_pfn; |
| |
| size = zone->spanned_pages; |
| realsize = freesize = zone->present_pages; |
| |
| /* |
| * 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 = calc_memmap_size(size, realsize); |
| if (!is_highmem_idx(j)) { |
| 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 |
| pr_warn(" %s zone: %lu pages exceeds freesize %lu\n", |
| zone_names[j], memmap_pages, freesize); |
| } |
| |
| /* Account for reserved pages */ |
| 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 += freesize; |
| /* Charge for highmem memmap if there are enough kernel pages */ |
| else if (nr_kernel_pages > memmap_pages * 2) |
| nr_kernel_pages -= memmap_pages; |
| nr_all_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; |
| #endif |
| zone->name = zone_names[j]; |
| zone->zone_pgdat = pgdat; |
| spin_lock_init(&zone->lock); |
| zone_seqlock_init(zone); |
| zone_pcp_init(zone); |
| |
| if (!size) |
| continue; |
| |
| set_pageblock_order(); |
| setup_usemap(pgdat, zone, zone_start_pfn, size); |
| ret = init_currently_empty_zone(zone, zone_start_pfn, size); |
| BUG_ON(ret); |
| memmap_init(size, nid, j, zone_start_pfn); |
| } |
| } |
| |
| static void __ref alloc_node_mem_map(struct pglist_data *pgdat) |
| { |
| unsigned long __maybe_unused start = 0; |
| unsigned long __maybe_unused offset = 0; |
| |
| /* Skip empty nodes */ |
| if (!pgdat->node_spanned_pages) |
| return; |
| |
| #ifdef CONFIG_FLAT_NODE_MEM_MAP |
| start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1); |
| offset = pgdat->node_start_pfn - start; |
| /* ia64 gets its own node_mem_map, before this, without bootmem */ |
| if (!pgdat->node_mem_map) { |
| unsigned long size, end; |
| struct page *map; |
| |
| /* |
| * The zone's endpoints aren't required to be MAX_ORDER |
| * aligned but the node_mem_map endpoints must be in order |
| * for the buddy allocator to function correctly. |
| */ |
| end = pgdat_end_pfn(pgdat); |
| end = ALIGN(end, MAX_ORDER_NR_PAGES); |
| size = (end - start) * sizeof(struct page); |
| map = alloc_remap(pgdat->node_id, size); |
| if (!map) |
| map = memblock_virt_alloc_node_nopanic(size, |
| pgdat->node_id); |
| pgdat->node_mem_map = map + offset; |
| } |
| #ifndef CONFIG_NEED_MULTIPLE_NODES |
| /* |
| * With no DISCONTIG, the global mem_map is just set as node 0's |
| */ |
| if (pgdat == NODE_DATA(0)) { |
| mem_map = NODE_DATA(0)->node_mem_map; |
| #if defined(CONFIG_HAVE_MEMBLOCK_NODE_MAP) || defined(CONFIG_FLATMEM) |
| if (page_to_pfn(mem_map) != pgdat->node_start_pfn) |
| mem_map -= offset; |
| #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ |
| } |
| #endif |
| #endif /* CONFIG_FLAT_NODE_MEM_MAP */ |
| } |
| |
| void __paginginit free_area_init_node(int nid, unsigned long *zones_size, |
| unsigned long node_start_pfn, unsigned long *zholes_size) |
| { |
| pg_data_t *pgdat = NODE_DATA(nid); |
| unsigned long start_pfn = 0; |
| unsigned long end_pfn = 0; |
| |
| /* pg_data_t should be reset to zero when it's allocated */ |
| WARN_ON(pgdat->nr_zones || pgdat->kswapd_classzone_idx); |
| |
| reset_deferred_meminit(pgdat); |
| pgdat->node_id = nid; |
| pgdat->node_start_pfn = node_start_pfn; |
| pgdat->per_cpu_nodestats = NULL; |
| #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP |
| get_pfn_range_for_nid(nid, &start_pfn, &end_pfn); |
| pr_info("Initmem setup node %d [mem %#018Lx-%#018Lx]\n", nid, |
| (u64)start_pfn << PAGE_SHIFT, |
| end_pfn ? ((u64)end_pfn << PAGE_SHIFT) - 1 : 0); |
| #else |
| start_pfn = node_start_pfn; |
| #endif |
| calculate_node_totalpages(pgdat, start_pfn, end_pfn, |
| zones_size, zholes_size); |
| |
| alloc_node_mem_map(pgdat); |
| #ifdef CONFIG_FLAT_NODE_MEM_MAP |
| printk(KERN_DEBUG "free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n", |
| nid, (unsigned long)pgdat, |
| (unsigned long)pgdat->node_mem_map); |
| #endif |
| |
| free_area_init_core(pgdat); |
| } |
| |
| #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP |
| |
| #if MAX_NUMNODES > 1 |
| /* |
| * Figure out the number of possible node ids. |
| */ |
| void __init setup_nr_node_ids(void) |
| { |
| unsigned int highest; |
| |
| highest = find_last_bit(node_possible_map.bits, MAX_NUMNODES); |
| nr_node_ids = highest + 1; |
| } |
| #endif |
| |
| /** |
| * node_map_pfn_alignment - determine the maximum internode alignment |
| * |
| * This function should be called after node map is populated and sorted. |
| * It calculates the maximum power of two alignment which can distinguish |
| * all the nodes. |
| * |
| * For example, if all nodes are 1GiB and aligned to 1GiB, the return value |
| * would indicate 1GiB alignment with (1 << (30 - PAGE_SHIFT)). If the |
| * nodes are shifted by 256MiB, 256MiB. Note that if only the last node is |
| * shifted, 1GiB is enough and this function will indicate so. |
| * |
| * This is used to test whether pfn -> nid mapping of the chosen memory |
| * model has fine enough granularity to avoid incorrect mapping for the |
| * populated node map. |
| * |
| * Returns the determined alignment in pfn's. 0 if there is no alignment |
| * requirement (single node). |
| */ |
| unsigned long __init node_map_pfn_alignment(void) |
| { |
| unsigned long accl_mask = 0, last_end = 0; |
| unsigned long start, end, mask; |
| int last_nid = -1; |
| int i, nid; |
| |
| for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, &nid) { |
| if (!start || last_nid < 0 || last_nid == nid) { |
| last_nid = nid; |
| last_end = end; |
| continue; |
| } |
| |
| /* |
| * Start with a mask granular enough to pin-point to the |
| * start pfn and tick off bits one-by-one until it becomes |
| * too coarse to separate the current node from the last. |
| */ |
| mask = ~((1 << __ffs(start)) - 1); |
| while (mask && last_end <= (start & (mask << 1))) |
| mask <<= 1; |
| |
| /* accumulate all internode masks */ |
| accl_mask |= mask; |
| } |
| |
| /* convert mask to number of pages */ |
| return ~accl_mask + 1; |
| } |
| |
| /* Find the lowest pfn for a node */ |
| static unsigned long __init find_min_pfn_for_node(int nid) |
| { |
| unsigned long min_pfn = ULONG_MAX; |
| unsigned long start_pfn; |
| int i; |
| |
| for_each_mem_pfn_range(i, nid, &start_pfn, NULL, NULL) |
| min_pfn = min(min_pfn, start_pfn); |
| |
| if (min_pfn == ULONG_MAX) { |
| pr_warn("Could not find start_pfn for node %d\n", nid); |
| return 0; |
| } |
| |
| return min_pfn; |
| } |
| |
| /** |
| * find_min_pfn_with_active_regions - Find the minimum PFN registered |
| * |
| * It returns the minimum PFN based on information provided via |
| * memblock_set_node(). |
| */ |
| unsigned long __init find_min_pfn_with_active_regions(void) |
| { |
| return find_min_pfn_for_node(MAX_NUMNODES); |
| } |
| |
| /* |
| * early_calculate_totalpages() |
| * Sum pages in active regions for movable zone. |
| * Populate N_MEMORY for calculating usable_nodes. |
| */ |
| static unsigned long __init early_calculate_totalpages(void) |
| { |
| unsigned long totalpages = 0; |
| unsigned long start_pfn, end_pfn; |
| int i, nid; |
| |
| for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) { |
| unsigned long pages = end_pfn - start_pfn; |
| |
| totalpages += pages; |
| if (pages) |
| node_set_state(nid, N_MEMORY); |
| } |
| return totalpages; |
| } |
| |
| /* |
| * Find the PFN the Movable zone begins in each node. Kernel memory |
| * is spread evenly between nodes as long as the nodes have enough |
| * memory. When they don't, some nodes will have more kernelcore than |
| * others |
| */ |
| static void __init find_zone_movable_pfns_for_nodes(void) |
| { |
| int i, nid; |
| unsigned long usable_startpfn; |
| unsigned long kernelcore_node, kernelcore_remaining; |
| /* save the state before borrow the nodemask */ |
| nodemask_t saved_node_state = node_states[N_MEMORY]; |
| unsigned long totalpages = early_calculate_totalpages(); |
| int usable_nodes = nodes_weight(node_states[N_MEMORY]); |
| struct memblock_region *r; |
| |
| /* Need to find movable_zone earlier when movable_node is specified. */ |
| find_usable_zone_for_movable(); |
| |
| /* |
| * If movable_node is specified, ignore kernelcore and movablecore |
| * options. |
| */ |
| if (movable_node_is_enabled()) { |
| for_each_memblock(memory, r) { |
| if (!memblock_is_hotpluggable(r)) |
| continue; |
| |
| nid = r->nid; |
| |
| usable_startpfn = PFN_DOWN(r->base); |
| zone_movable_pfn[nid] = zone_movable_pfn[nid] ? |
| min(usable_startpfn, zone_movable_pfn[nid]) : |
| usable_startpfn; |
| } |
| |
| goto out2; |
| } |
| |
| /* |
| * If kernelcore=mirror is specified, ignore movablecore option |
| */ |
| if (mirrored_kernelcore) { |
| bool mem_below_4gb_not_mirrored = false; |
| |
| for_each_memblock(memory, r) { |
| if (memblock_is_mirror(r)) |
| continue; |
| |
| nid = r->nid; |
| |
| usable_startpfn = memblock_region_memory_base_pfn(r); |
| |
| if (usable_startpfn < 0x100000) { |
| mem_below_4gb_not_mirrored = true; |
| continue; |
| } |
| |
| zone_movable_pfn[nid] = zone_movable_pfn[nid] ? |
| min(usable_startpfn, zone_movable_pfn[nid]) : |
| usable_startpfn; |
| } |
| |
| if (mem_below_4gb_not_mirrored) |
| pr_warn("This configuration results in unmirrored kernel memory."); |
| |
| goto out2; |
| } |
| |
| /* |
| * If movablecore=nn[KMG] was specified, calculate what size of |
| * kernelcore that corresponds so that memory usable for |
| * any allocation type is evenly spread. If both kernelcore |
| * and movablecore are specified, then the value of kernelcore |
| * will be used for required_kernelcore if it's greater than |
| * what movablecore would have allowed. |
| */ |
| if (required_movablecore) { |
| unsigned long corepages; |
| |
| /* |
| * Round-up so that ZONE_MOVABLE is at least as large as what |
| * was requested by the user |
| */ |
| required_movablecore = |
| roundup(required_movablecore, MAX_ORDER_NR_PAGES); |
| required_movablecore = min(totalpages, required_movablecore); |
| corepages = totalpages - required_movablecore; |
| |
| required_kernelcore = max(required_kernelcore, corepages); |
| } |
| |
| /* |
| * If kernelcore was not specified or kernelcore size is larger |
| * than totalpages, there is no ZONE_MOVABLE. |
| */ |
| if (!required_kernelcore || required_kernelcore >= totalpages) |
| goto out; |
| |
| /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */ |
| usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone]; |
| |
| restart: |
| /* Spread kernelcore memory as evenly as possible throughout nodes */ |
| kernelcore_node = required_kernelcore / usable_nodes; |
| for_each_node_state(nid, N_MEMORY) { |
| unsigned long start_pfn, end_pfn; |
| |
| /* |
| * Recalculate kernelcore_node if the division per node |
| * now exceeds what is necessary to satisfy the requested |
| * amount of memory for the kernel |
| */ |
| if (required_kernelcore < kernelcore_node) |
| kernelcore_node = required_kernelcore / usable_nodes; |
| |
| /* |
| * As the map is walked, we track how much memory is usable |
| * by the kernel using kernelcore_remaining. When it is |
| * 0, the rest of the node is usable by ZONE_MOVABLE |
| */ |
| kernelcore_remaining = kernelcore_node; |
| |
| /* Go through each range of PFNs within this node */ |
| for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) { |
| unsigned long size_pages; |
| |
| start_pfn = max(start_pfn, zone_movable_pfn[nid]); |
| if (start_pfn >= end_pfn) |
| continue; |
| |
| /* Account for what is only usable for kernelcore */ |
| if (start_pfn < usable_startpfn) { |
| unsigned long kernel_pages; |
| kernel_pages = min(end_pfn, usable_startpfn) |
| - start_pfn; |
| |
| kernelcore_remaining -= min(kernel_pages, |
| kernelcore_remaining); |
| required_kernelcore -= min(kernel_pages, |
| required_kernelcore); |
| |
| /* Continue if range is now fully accounted */ |
| if (end_pfn <= usable_startpfn) { |
| |
| /* |
| * Push zone_movable_pfn to the end so |
| * that if we have to rebalance |
| * kernelcore across nodes, we will |
| * not double account here |
| */ |
| zone_movable_pfn[nid] = end_pfn; |
| continue; |
| } |
| start_pfn = usable_startpfn; |
| } |
| |
| /* |
| * The usable PFN range for ZONE_MOVABLE is from |
| * start_pfn->end_pfn. Calculate size_pages as the |
| * number of pages used as kernelcore |
| */ |
| size_pages = end_pfn - start_pfn; |
| if (size_pages > kernelcore_remaining) |
| size_pages = kernelcore_remaining; |
| zone_movable_pfn[nid] = start_pfn + size_pages; |
| |
| /* |
| * Some kernelcore has been met, update counts and |
| * break if the kernelcore for this node has been |
| * satisfied |
| */ |
| required_kernelcore -= min(required_kernelcore, |
| size_pages); |
| kernelcore_remaining -= size_pages; |
| if (!kernelcore_remaining) |
| break; |
| } |
| } |
| |
| /* |
| * If there is still required_kernelcore, we do another pass with one |
| * less node in the count. This will push zone_movable_pfn[nid] further |
| * along on the nodes that still have memory until kernelcore is |
| * satisfied |
| */ |
| usable_nodes--; |
| if (usable_nodes && required_kernelcore > usable_nodes) |
| goto restart; |
| |
| out2: |
| /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */ |
| for (nid = 0; nid < MAX_NUMNODES; nid++) |
| zone_movable_pfn[nid] = |
| roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES); |
| |
| out: |
| /* restore the node_state */ |
| node_states[N_MEMORY] = saved_node_state; |
| } |
| |
| /* Any regular or high memory on that node ? */ |
| static void check_for_memory(pg_data_t *pgdat, int nid) |
| { |
| enum zone_type zone_type; |
| |
| if (N_MEMORY == N_NORMAL_MEMORY) |
| return; |
| |
| for (zone_type = 0; zone_type <= ZONE_MOVABLE - 1; zone_type++) { |
| struct zone *zone = &pgdat->node_zones[zone_type]; |
| if (populated_zone(zone)) { |
| node_set_state(nid, N_HIGH_MEMORY); |
| if (N_NORMAL_MEMORY != N_HIGH_MEMORY && |
| zone_type <= ZONE_NORMAL) |
| node_set_state(nid, N_NORMAL_MEMORY); |
| break; |
| } |
| } |
| } |
| |
| /** |
| * free_area_init_nodes - Initialise all pg_data_t and zone data |
| * @max_zone_pfn: an array of max PFNs for each zone |
| * |
| * This will call free_area_init_node() for each active node in the system. |
| * Using the page ranges provided by memblock_set_node(), the size of each |
| * zone in each node and their holes is calculated. If the maximum PFN |
| * between two adjacent zones match, it is assumed that the zone is empty. |
| * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed |
| * that arch_max_dma32_pfn has no pages. It is also assumed that a zone |
| * starts where the previous one ended. For example, ZONE_DMA32 starts |
| * at arch_max_dma_pfn. |
| */ |
| void __init free_area_init_nodes(unsigned long *max_zone_pfn) |
| { |
| unsigned long start_pfn, end_pfn; |
| int i, nid; |
| |
| /* Record where the zone boundaries are */ |
| memset(arch_zone_lowest_possible_pfn, 0, |
| sizeof(arch_zone_lowest_possible_pfn)); |
| memset(arch_zone_highest_possible_pfn, 0, |
| sizeof(arch_zone_highest_possible_pfn)); |
| |
| start_pfn = find_min_pfn_with_active_regions(); |
| |
| for (i = 0; i < MAX_NR_ZONES; i++) { |
| if (i == ZONE_MOVABLE) |
| continue; |
| |
| end_pfn = max(max_zone_pfn[i], start_pfn); |
| arch_zone_lowest_possible_pfn[i] = start_pfn; |
| arch_zone_highest_possible_pfn[i] = end_pfn; |
| |
| start_pfn = end_pfn; |
| } |
| arch_zone_lowest_possible_pfn[ZONE_MOVABLE] = 0; |
| arch_zone_highest_possible_pfn[ZONE_MOVABLE] = 0; |
| |
| /* Find the PFNs that ZONE_MOVABLE begins at in each node */ |
| memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn)); |
| find_zone_movable_pfns_for_nodes(); |
| |
| /* Print out the zone ranges */ |
| pr_info("Zone ranges:\n"); |
| for (i = 0; i < MAX_NR_ZONES; i++) { |
| if (i == ZONE_MOVABLE) |
| continue; |
| pr_info(" %-8s ", zone_names[i]); |
| if (arch_zone_lowest_possible_pfn[i] == |
| arch_zone_highest_possible_pfn[i]) |
| pr_cont("empty\n"); |
| else |
| pr_cont("[mem %#018Lx-%#018Lx]\n", |
| (u64)arch_zone_lowest_possible_pfn[i] |
| << PAGE_SHIFT, |
| ((u64)arch_zone_highest_possible_pfn[i] |
| << PAGE_SHIFT) - 1); |
| } |
| |
| /* Print out the PFNs ZONE_MOVABLE begins at in each node */ |
| pr_info("Movable zone start for each node\n"); |
| for (i = 0; i < MAX_NUMNODES; i++) { |
| if (zone_movable_pfn[i]) |
| pr_info(" Node %d: %#018Lx\n", i, |
| (u64)zone_movable_pfn[i] << PAGE_SHIFT); |
| } |
| |
| /* Print out the early node map */ |
| pr_info("Early memory node ranges\n"); |
| for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) |
| pr_info(" node %3d: [mem %#018Lx-%#018Lx]\n", nid, |
| (u64)start_pfn << PAGE_SHIFT, |
| ((u64)end_pfn << PAGE_SHIFT) - 1); |
| |
| /* Initialise every node */ |
| mminit_verify_pageflags_layout(); |
| setup_nr_node_ids(); |
| for_each_online_node(nid) { |
| pg_data_t *pgdat = NODE_DATA(nid); |
| free_area_init_node(nid, NULL, |
| find_min_pfn_for_node(nid), NULL); |
| |
| /* Any memory on that node */ |
| if (pgdat->node_present_pages) |
| node_set_state(nid, N_MEMORY); |
| check_for_memory(pgdat, nid); |
| } |
| } |
| |
| static int __init cmdline_parse_core(char *p, unsigned long *core) |
| { |
| unsigned long long coremem; |
| if (!p) |
| return -EINVAL; |
| |
| coremem = memparse(p, &p); |
| *core = coremem >> PAGE_SHIFT; |
| |
| /* Paranoid check that UL is enough for the coremem value */ |
| WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX); |
| |
| return 0; |
| } |
| |
| /* |
| * kernelcore=size sets the amount of memory for use for allocations that |
| * cannot be reclaimed or migrated. |
| */ |
| static int __init cmdline_parse_kernelcore(char *p) |
| { |
| /* parse kernelcore=mirror */ |
| if (parse_option_str(p, "mirror")) { |
| mirrored_kernelcore = true; |
| return 0; |
| } |
| |
| return cmdline_parse_core(p, &required_kernelcore); |
| } |
| |
| /* |
| * movablecore=size sets the amount of memory for use for allocations that |
| * can be reclaimed or migrated. |
| */ |
| static int __init cmdline_parse_movablecore(char *p) |
| { |
| return cmdline_parse_core(p, &required_movablecore); |
| } |
| |
| early_param("kernelcore", cmdline_parse_kernelcore); |
| early_param("movablecore", cmdline_parse_movablecore); |
| |
| #endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */ |
| |
| void adjust_managed_page_count(struct page *page, long count) |
| { |
| spin_lock(&managed_page_count_lock); |
| page_zone(page)->managed_pages += count; |
| totalram_pages += count; |
| #ifdef CONFIG_HIGHMEM |
| if (PageHighMem(page)) |
| totalhigh_pages += count; |
| #endif |
| spin_unlock(&managed_page_count_lock); |
| } |
| EXPORT_SYMBOL(adjust_managed_page_count); |
| |
| unsigned long free_reserved_area(void *start, void *end, int poison, char *s) |
| { |
| void *pos; |
| unsigned long pages = 0; |
| |
| start = (void *)PAGE_ALIGN((unsigned long)start); |
| end = (void *)((unsigned long)end & PAGE_MASK); |
| for (pos = start; pos < end; pos += PAGE_SIZE, pages++) { |
| if ((unsigned int)poison <= 0xFF) |
| memset(pos, poison, PAGE_SIZE); |
| free_reserved_page(virt_to_page(pos)); |
| } |
| |
| if (pages && s) |
| pr_info("Freeing %s memory: %ldK (%p - %p)\n", |
| s, pages << (PAGE_SHIFT - 10), start, end); |
| |
| return pages; |
| } |
| EXPORT_SYMBOL(free_reserved_area); |
| |
| #ifdef CONFIG_HIGHMEM |
| void free_highmem_page(struct page *page) |
| { |
| __free_reserved_page(page); |
| totalram_pages++; |
| page_zone(page)->managed_pages++; |
| totalhigh_pages++; |
| } |
| #endif |
| |
| |
| void __init mem_init_print_info(const char *str) |
| { |
| unsigned long physpages, codesize, datasize, rosize, bss_size; |
| unsigned long init_code_size, init_data_size; |
| |
| physpages = get_num_physpages(); |
| codesize = _etext - _stext; |
| datasize = _edata - _sdata; |
| rosize = __end_rodata - __start_rodata; |
| bss_size = __bss_stop - __bss_start; |
| init_data_size = __init_end - __init_begin; |
| init_code_size = _einittext - _sinittext; |
| |
| /* |
| * Detect special cases and adjust section sizes accordingly: |
| * 1) .init.* may be embedded into .data sections |
| * 2) .init.text.* may be out of [__init_begin, __init_end], |
| * please refer to arch/tile/kernel/vmlinux.lds.S. |
| * 3) .rodata.* may be embedded into .text or .data sections. |
| */ |
| #define adj_init_size(start, end, size, pos, adj) \ |
| do { \ |
| if (start <= pos && pos < end && size > adj) \ |
| size -= adj; \ |
| } while (0) |
| |
| adj_init_size(__init_begin, __init_end, init_data_size, |
| _sinittext, init_code_size); |
| adj_init_size(_stext, _etext, codesize, _sinittext, init_code_size); |
| adj_init_size(_sdata, _edata, datasize, __init_begin, init_data_size); |
| adj_init_size(_stext, _etext, codesize, __start_rodata, rosize); |
| adj_init_size(_sdata, _edata, datasize, __start_rodata, rosize); |
| |
| #undef adj_init_size |
| |
| pr_info("Memory: %luK/%luK available (%luK kernel code, %luK rwdata, %luK rodata, %luK init, %luK bss, %luK reserved, %luK cma-reserved" |
| #ifdef CONFIG_HIGHMEM |
| ", %luK highmem" |
| #endif |
| "%s%s)\n", |
| nr_free_pages() << (PAGE_SHIFT - 10), |
| physpages << (PAGE_SHIFT - 10), |
| codesize >> 10, datasize >> 10, rosize >> 10, |
| (init_data_size + init_code_size) >> 10, bss_size >> 10, |
| (physpages - totalram_pages - totalcma_pages) << (PAGE_SHIFT - 10), |
| totalcma_pages << (PAGE_SHIFT - 10), |
| #ifdef CONFIG_HIGHMEM |
| totalhigh_pages << (PAGE_SHIFT - 10), |
| #endif |
| str ? ", " : "", str ? str : ""); |
| } |
| |
| /** |
| * set_dma_reserve - set the specified number of pages reserved in the first zone |
| * @new_dma_reserve: The number of pages to mark reserved |
| * |
| * The per-cpu batchsize and zone watermarks are determined by managed_pages. |
| * In the DMA zone, a significant percentage may be consumed by kernel image |
| * and other unfreeable allocations which can skew the watermarks badly. This |
| * function may optionally be used to account for unfreeable pages in the |
| * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and |
| * smaller per-cpu batchsize. |
| */ |
| void __init set_dma_reserve(unsigned long new_dma_reserve) |
| { |
| dma_reserve = new_dma_reserve; |
| } |
| |
| void __init free_area_init(unsigned long *zones_size) |
| { |
| free_area_init_node(0, zones_size, |
| __pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL); |
| } |
| |
| static int page_alloc_cpu_notify(struct notifier_block *self, |
| unsigned long action, void *hcpu) |
| { |
| int cpu = (unsigned long)hcpu; |
| |
| if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) { |
| lru_add_drain_cpu(cpu); |
| drain_pages(cpu); |
| |
| /* |
| * Spill the event counters of the dead processor |
| * into the current processors event counters. |
| * This artificially elevates the count of the current |
| * processor. |
| */ |
| vm_events_fold_cpu(cpu); |
| |
| /* |
| * Zero the differential counters of the dead processor |
| * so that the vm statistics are consistent. |
| * |
| * This is only okay since the processor is dead and cannot |
| * race with what we are doing. |
| */ |
| cpu_vm_stats_fold(cpu); |
| } |
| return NOTIFY_OK; |
| } |
| |
| void __init page_alloc_init(void) |
| { |
| hotcpu_notifier(page_alloc_cpu_notify, 0); |
| } |
| |
| /* |
| * calculate_totalreserve_pages - called when sysctl_lowmem_reserve_ratio |
| * or min_free_kbytes changes. |
| */ |
| static void calculate_totalreserve_pages(void) |
| { |
| struct pglist_data *pgdat; |
| unsigned long reserve_pages = 0; |
| enum zone_type i, j; |
| |
| for_each_online_pgdat(pgdat) { |
| |
| pgdat->totalreserve_pages = 0; |
| |
| for (i = 0; i < MAX_NR_ZONES; i++) { |
| struct zone *zone = pgdat->node_zones + i; |
| long max = 0; |
| |
| /* Find valid and maximum lowmem_reserve in the zone */ |
| for (j = i; j < MAX_NR_ZONES; j++) { |
| if (zone->lowmem_reserve[j] > max) |
| max = zone->lowmem_reserve[j]; |
| } |
| |
| /* we treat the high watermark as reserved pages. */ |
| max += high_wmark_pages(zone); |
| |
| if (max > zone->managed_pages) |
| max = zone->managed_pages; |
| |
| pgdat->totalreserve_pages += max; |
| |
| reserve_pages += max; |
| } |
| } |
| totalreserve_pages = reserve_pages; |
| } |
| |
| /* |
| * setup_per_zone_lowmem_reserve - called whenever |
| * sysctl_lowmem_reserve_ratio changes. Ensures that each zone |
| * has a correct pages reserved value, so an adequate number of |
| * pages are left in the zone after a successful __alloc_pages(). |
| */ |
| static void setup_per_zone_lowmem_reserve(void) |
| { |
| struct pglist_data *pgdat; |
| enum zone_type j, idx; |
| |
| for_each_online_pgdat(pgdat) { |
| for (j = 0; j < MAX_NR_ZONES; j++) { |
| struct zone *zone = pgdat->node_zones + j; |
| unsigned long managed_pages = zone->managed_pages; |
| |
| zone->lowmem_reserve[j] = 0; |
| |
| idx = j; |
| while (idx) { |
| struct zone *lower_zone; |
| |
| idx--; |
| |
| if (sysctl_lowmem_reserve_ratio[idx] < 1) |
| sysctl_lowmem_reserve_ratio[idx] = 1; |
| |
| lower_zone = pgdat->node_zones + idx; |
| lower_zone->lowmem_reserve[j] = managed_pages / |
| sysctl_lowmem_reserve_ratio[idx]; |
| managed_pages += lower_zone->managed_pages; |
| } |
| } |
| } |
| |
| /* update totalreserve_pages */ |
| calculate_totalreserve_pages(); |
| } |
| |
| static void __setup_per_zone_wmarks(void) |
| { |
| unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10); |
| unsigned long lowmem_pages = 0; |
| struct zone *zone; |
| unsigned long flags; |
| |
| /* Calculate total number of !ZONE_HIGHMEM pages */ |
| for_each_zone(zone) { |
| if (!is_highmem(zone)) |
| lowmem_pages += zone->managed_pages; |
| } |
| |
| for_each_zone(zone) { |
| u64 tmp; |
| |
| spin_lock_irqsave(&zone->lock, flags); |
| tmp = (u64)pages_min * zone->managed_pages; |
| do_div(tmp, lowmem_pages); |
| if (is_highmem(zone)) { |
| /* |
| * __GFP_HIGH and PF_MEMALLOC allocations usually don't |
| * need highmem pages, so cap pages_min to a small |
| * value here. |
| * |
| * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN) |
| * deltas control asynch page reclaim, and so should |
| * not be capped for highmem. |
| */ |
| unsigned long min_pages; |
| |
| min_pages = zone->managed_pages / 1024; |
| min_pages = clamp(min_pages, SWAP_CLUSTER_MAX, 128UL); |
| zone->watermark[WMARK_MIN] = min_pages; |
| } else { |
| /* |
| * If it's a lowmem zone, reserve a number of pages |
| * proportionate to the zone's size. |
| */ |
| zone->watermark[WMARK_MIN] = tmp; |
| } |
| |
| /* |
| * Set the kswapd watermarks distance according to the |
| * scale factor in proportion to available memory, but |
| * ensure a minimum size on small systems. |
| */ |
| tmp = max_t(u64, tmp >> 2, |
| mult_frac(zone->managed_pages, |
| watermark_scale_factor, 10000)); |
| |
| zone->watermark[WMARK_LOW] = min_wmark_pages(zone) + tmp; |
| zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + tmp * 2; |
| |
| spin_unlock_irqrestore(&zone->lock, flags); |
| } |
| |
| /* update totalreserve_pages */ |
| calculate_totalreserve_pages(); |
| } |
| |
| /** |
| * setup_per_zone_wmarks - called when min_free_kbytes changes |
| * or when memory is hot-{added|removed} |
| * |
| * Ensures that the watermark[min,low,high] values for each zone are set |
| * correctly with respect to min_free_kbytes. |
| */ |
| void setup_per_zone_wmarks(void) |
| { |
| mutex_lock(&zonelists_mutex); |
| __setup_per_zone_wmarks(); |
| mutex_unlock(&zonelists_mutex); |
| } |
| |
| /* |
| * Initialise min_free_kbytes. |
| * |
| * For small machines we want it small (128k min). For large machines |
| * we want it large (64MB max). But it is not linear, because network |
| * bandwidth does not increase linearly with machine size. We use |
| * |
| * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy: |
| * min_free_kbytes = sqrt(lowmem_kbytes * 16) |
| * |
| * which yields |
| * |
| * 16MB: 512k |
| * 32MB: 724k |
| * 64MB: 1024k |
| * 128MB: 1448k |
| * 256MB: 2048k |
| * 512MB: 2896k |
| * 1024MB: 4096k |
| * 2048MB: 5792k |
| * 4096MB: 8192k |
| * 8192MB: 11584k |
| * 16384MB: 16384k |
| */ |
| int __meminit init_per_zone_wmark_min(void) |
| { |
| unsigned long lowmem_kbytes; |
| int new_min_free_kbytes; |
| |
| lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10); |
| new_min_free_kbytes = int_sqrt(lowmem_kbytes * 16); |
| |
| if (new_min_free_kbytes > user_min_free_kbytes) { |
| min_free_kbytes = new_min_free_kbytes; |
| if (min_free_kbytes < 128) |
| min_free_kbytes = 128; |
| if (min_free_kbytes > 65536) |
| min_free_kbytes = 65536; |
| } else { |
| pr_warn("min_free_kbytes is not updated to %d because user defined value %d is preferred\n", |
| new_min_free_kbytes, user_min_free_kbytes); |
| } |
| setup_per_zone_wmarks(); |
| refresh_zone_stat_thresholds(); |
| setup_per_zone_lowmem_reserve(); |
| |
| #ifdef CONFIG_NUMA |
| setup_min_unmapped_ratio(); |
| setup_min_slab_ratio(); |
| #endif |
| |
| return 0; |
| } |
| core_initcall(init_per_zone_wmark_min) |
| |
| /* |
| * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so |
| * that we can call two helper functions whenever min_free_kbytes |
| * changes. |
| */ |
| int min_free_kbytes_sysctl_handler(struct ctl_table *table, int write, |
| void __user *buffer, size_t *length, loff_t *ppos) |
| { |
| int rc; |
| |
| rc = proc_dointvec_minmax(table, write, buffer, length, ppos); |
| if (rc) |
| return rc; |
| |
| if (write) { |
| user_min_free_kbytes = min_free_kbytes; |
| setup_per_zone_wmarks(); |
| } |
| return 0; |
| } |
| |
| int watermark_scale_factor_sysctl_handler(struct ctl_table *table, int write, |
| void __user *buffer, size_t *length, loff_t *ppos) |
| { |
| int rc; |
| |
| rc = proc_dointvec_minmax(table, write, buffer, length, ppos); |
| if (rc) |
| return rc; |
| |
| if (write) |
| setup_per_zone_wmarks(); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_NUMA |
| static void setup_min_unmapped_ratio(void) |
| { |
| pg_data_t *pgdat; |
| struct zone *zone; |
| |
| for_each_online_pgdat(pgdat) |
| pgdat->min_unmapped_pages = 0; |
| |
| for_each_zone(zone) |
| zone->zone_pgdat->min_unmapped_pages += (zone->managed_pages * |
| sysctl_min_unmapped_ratio) / 100; |
| } |
| |
| |
| int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *table, int write, |
| void __user *buffer, size_t *length, loff_t *ppos) |
| { |
| int rc; |
| |
| rc = proc_dointvec_minmax(table, write, buffer, length, ppos); |
| if (rc) |
| return rc; |
| |
| setup_min_unmapped_ratio(); |
| |
| return 0; |
| } |
| |
| static void setup_min_slab_ratio(void) |
| { |
| pg_data_t *pgdat; |
| struct zone *zone; |
| |
| for_each_online_pgdat(pgdat) |
| pgdat->min_slab_pages = 0; |
| |
| for_each_zone(zone) |
| zone->zone_pgdat->min_slab_pages += (zone->managed_pages * |
| sysctl_min_slab_ratio) / 100; |
| } |
| |
| int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *table, int write, |
| void __user *buffer, size_t *length, loff_t *ppos) |
| { |
| int rc; |
| |
| rc = proc_dointvec_minmax(table, write, buffer, length, ppos); |
| if (rc) |
| return rc; |
| |
| setup_min_slab_ratio(); |
| |
| return 0; |
| } |
| #endif |
| |
| /* |
| * lowmem_reserve_ratio_sysctl_handler - just a wrapper around |
| * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve() |
| * whenever sysctl_lowmem_reserve_ratio changes. |
| * |
| * The reserve ratio obviously has absolutely no relation with the |
| * minimum watermarks. The lowmem reserve ratio can only make sense |
| * if in function of the boot time zone sizes. |
| */ |
| int lowmem_reserve_ratio_sysctl_handler(struct ctl_table *table, int write, |
| void __user *buffer, size_t *length, loff_t *ppos) |
| { |
| proc_dointvec_minmax(table, write, buffer, length, ppos); |
| setup_per_zone_lowmem_reserve(); |
| return 0; |
| } |
| |
| /* |
| * percpu_pagelist_fraction - changes the 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. |
| */ |
| int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *table, int write, |
| void __user *buffer, size_t *length, loff_t *ppos) |
| { |
| struct zone *zone; |
| int old_percpu_pagelist_fraction; |
| int ret; |
| |
| mutex_lock(&pcp_batch_high_lock); |
| old_percpu_pagelist_fraction = percpu_pagelist_fraction; |
| |
| ret = proc_dointvec_minmax(table, write, buffer, length, ppos); |
| if (!write || ret < 0) |
| goto out; |
| |
| /* Sanity checking to avoid pcp imbalance */ |
| if (percpu_pagelist_fraction && |
| percpu_pagelist_fraction < MIN_PERCPU_PAGELIST_FRACTION) { |
| percpu_pagelist_fraction = old_percpu_pagelist_fraction; |
| ret = -EINVAL; |
| goto out; |
| } |
| |
| /* No change? */ |
| if (percpu_pagelist_fraction == old_percpu_pagelist_fraction) |
| goto out; |
| |
| for_each_populated_zone(zone) { |
| unsigned int cpu; |
| |
| for_each_possible_cpu(cpu) |
| pageset_set_high_and_batch(zone, |
| per_cpu_ptr(zone->pageset, cpu)); |
| } |
| out: |
| mutex_unlock(&pcp_batch_high_lock); |
| return ret; |
| } |
| |
| #ifdef CONFIG_NUMA |
| int hashdist = HASHDIST_DEFAULT; |
| |
| static int __init set_hashdist(char *str) |
| { |
| if (!str) |
| return 0; |
| hashdist = simple_strtoul(str, &str, 0); |
| return 1; |
| } |
| __setup("hashdist=", set_hashdist); |
| #endif |
| |
| #ifndef __HAVE_ARCH_RESERVED_KERNEL_PAGES |
| /* |
| * Returns the number of pages that arch has reserved but |
| * is not known to alloc_large_system_hash(). |
| */ |
| static unsigned long __init arch_reserved_kernel_pages(void) |
| { |
| return 0; |
| } |
| #endif |
| |
| /* |
| * allocate a large system hash table from bootmem |
| * - it is assumed that the hash table must contain an exact power-of-2 |
| * quantity of entries |
| * - limit is the number of hash buckets, not the total allocation size |
| */ |
| void *__init alloc_large_system_hash(const char *tablename, |
| unsigned long bucketsize, |
| unsigned long numentries, |
| int scale, |
| int flags, |
| unsigned int *_hash_shift, |
| unsigned int *_hash_mask, |
| unsigned long low_limit, |
| unsigned long high_limit) |
| { |
| unsigned long long max = high_limit; |
| unsigned long log2qty, size; |
| void *table = NULL; |
| |
| /* allow the kernel cmdline to have a say */ |
| if (!numentries) { |
| /* round applicable memory size up to nearest megabyte */ |
| numentries = nr_kernel_pages; |
| numentries -= arch_reserved_kernel_pages(); |
| |
| /* It isn't necessary when PAGE_SIZE >= 1MB */ |
| if (PAGE_SHIFT < 20) |
| numentries = round_up(numentries, (1<<20)/PAGE_SIZE); |
| |
| /* limit to 1 bucket per 2^scale bytes of low memory */ |
| if (scale > PAGE_SHIFT) |
| numentries >>= (scale - PAGE_SHIFT); |
| else |
| numentries <<= (PAGE_SHIFT - scale); |
| |
| /* Make sure we've got at least a 0-order allocation.. */ |
| if (unlikely(flags & HASH_SMALL)) { |
| /* Makes no sense without HASH_EARLY */ |
| WARN_ON(!(flags & HASH_EARLY)); |
| if (!(numentries >> *_hash_shift)) { |
| numentries = 1UL << *_hash_shift; |
| BUG_ON(!numentries); |
| } |
| } else if (unlikely((numentries * bucketsize) < PAGE_SIZE)) |
| numentries = PAGE_SIZE / bucketsize; |
| } |
| numentries = roundup_pow_of_two(numentries); |
| |
| /* limit allocation size to 1/16 total memory by default */ |
| if (max == 0) { |
| max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4; |
| do_div(max, bucketsize); |
| } |
| max = min(max, 0x80000000ULL); |
| |
| if (numentries < low_limit) |
| numentries = low_limit; |
| if (numentries > max) |
| numentries = max; |
| |
| log2qty = ilog2(numentries); |
| |
| do { |
| size = bucketsize << log2qty; |
| if (flags & HASH_EARLY) |
| table = memblock_virt_alloc_nopanic(size, 0); |
| else if (hashdist) |
| table = __vmalloc(size, GFP_ATOMIC, PAGE_KERNEL); |
| else { |
| /* |
| * If bucketsize is not a power-of-two, we may free |
| * some pages at the end of hash table which |
| * alloc_pages_exact() automatically does |
| */ |
| if (get_order(size) < MAX_ORDER) { |
| table = alloc_pages_exact(size, GFP_ATOMIC); |
| kmemleak_alloc(table, size, 1, GFP_ATOMIC); |
| } |
| } |
| } while (!table && size > PAGE_SIZE && --log2qty); |
| |
| if (!table) |
| panic("Failed to allocate %s hash table\n", tablename); |
| |
| pr_info("%s hash table entries: %ld (order: %d, %lu bytes)\n", |
| tablename, 1UL << log2qty, ilog2(size) - PAGE_SHIFT, size); |
| |
| if (_hash_shift) |
| *_hash_shift = log2qty; |
| if (_hash_mask) |
| *_hash_mask = (1 << log2qty) - 1; |
| |
| return table; |
| } |
| |
| /* |
| * This function checks whether pageblock includes unmovable pages or not. |
| * If @count is not zero, it is okay to include less @count unmovable pages |
| * |
| * PageLRU check without isolation or lru_lock could race so that |
| * MIGRATE_MOVABLE block might include unmovable pages. It means you can't |
| * expect this function should be exact. |
| */ |
| bool has_unmovable_pages(struct zone *zone, struct page *page, int count, |
| bool skip_hwpoisoned_pages) |
| { |
| unsigned long pfn, iter, found; |
| int mt; |
| |
| /* |
| * For avoiding noise data, lru_add_drain_all() should be called |
| * If ZONE_MOVABLE, the zone never contains unmovable pages |
| */ |
| if (zone_idx(zone) == ZONE_MOVABLE) |
| return false; |
| mt = get_pageblock_migratetype(page); |
| if (mt == MIGRATE_MOVABLE || is_migrate_cma(mt)) |
| return false; |
| |
| pfn = page_to_pfn(page); |
| for (found = 0, iter = 0; iter < pageblock_nr_pages; iter++) { |
| unsigned long check = pfn + iter; |
| |
| if (!pfn_valid_within(check)) |
| continue; |
| |
| page = pfn_to_page(check); |
| |
| /* |
| * Hugepages are not in LRU lists, but they're movable. |
| * We need not scan over tail pages bacause we don't |
| * handle each tail page individually in migration. |
| */ |
| if (PageHuge(page)) { |
| iter = round_up(iter + 1, 1<<compound_order(page)) - 1; |
| continue; |
| } |
| |
| /* |
| * We can't use page_count without pin a page |
| * because another CPU can free compound page. |
| * This check already skips compound tails of THP |
| * because their page->_refcount is zero at all time. |
| */ |
| if (!page_ref_count(page)) { |
| if (PageBuddy(page)) |
| iter += (1 << page_order(page)) - 1; |
| continue; |
| } |
| |
| /* |
| * The HWPoisoned page may be not in buddy system, and |
| * page_count() is not 0. |
| */ |
| if (skip_hwpoisoned_pages && PageHWPoison(page)) |
| continue; |
| |
| if (!PageLRU(page)) |
| found++; |
| /* |
| * If there are RECLAIMABLE pages, we need to check |
| * it. But now, memory offline itself doesn't call |
| * shrink_node_slabs() and it still to be fixed. |
| */ |
| /* |
| * If the page is not RAM, page_count()should be 0. |
| * we don't need more check. This is an _used_ not-movable page. |
| * |
| * The problematic thing here is PG_reserved pages. PG_reserved |
| * is set to both of a memory hole page and a _used_ kernel |
| * page at boot. |
| */ |
| if (found > count) |
| return true; |
| } |
| return false; |
| } |
| |
| bool is_pageblock_removable_nolock(struct page *page) |
| { |
| struct zone *zone; |
| unsigned long pfn; |
| |
| /* |
| * We have to be careful here because we are iterating over memory |
| * sections which are not zone aware so we might end up outside of |
| * the zone but still within the section. |
| * We have to take care about the node as well. If the node is offline |
| * its NODE_DATA will be NULL - see page_zone. |
| */ |
| if (!node_online(page_to_nid(page))) |
| return false; |
| |
| zone = page_zone(page); |
| pfn = page_to_pfn(page); |
| if (!zone_spans_pfn(zone, pfn)) |
| return false; |
| |
| return !has_unmovable_pages(zone, page, 0, true); |
| } |
| |
| #if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA) |
| |
| static unsigned long pfn_max_align_down(unsigned long pfn) |
| { |
| return pfn & ~(max_t(unsigned long, MAX_ORDER_NR_PAGES, |
| pageblock_nr_pages) - 1); |
| } |
| |
| static unsigned long pfn_max_align_up(unsigned long pfn) |
| { |
| return ALIGN(pfn, max_t(unsigned long, MAX_ORDER_NR_PAGES, |
| pageblock_nr_pages)); |
| } |
| |
| /* [start, end) must belong to a single zone. */ |
| static int __alloc_contig_migrate_range(struct compact_control *cc, |
| unsigned long start, unsigned long end) |
| { |
| /* This function is based on compact_zone() from compaction.c. */ |
| unsigned long nr_reclaimed; |
| unsigned long pfn = start; |
| unsigned int tries = 0; |
| int ret = 0; |
| |
| migrate_prep(); |
| |
| while (pfn < end || !list_empty(&cc->migratepages)) { |
| if (fatal_signal_pending(current)) { |
| ret = -EINTR; |
| break; |
| } |
| |
| if (list_empty(&cc->migratepages)) { |
| cc->nr_migratepages = 0; |
| pfn = isolate_migratepages_range(cc, pfn, end); |
| if (!pfn) { |
| ret = -EINTR; |
| break; |
| } |
| tries = 0; |
| } else if (++tries == 5) { |
| ret = ret < 0 ? ret : -EBUSY; |
| break; |
| } |
| |
| nr_reclaimed = reclaim_clean_pages_from_list(cc->zone, |
| &cc->migratepages); |
| cc->nr_migratepages -= nr_reclaimed; |
| |
| ret = migrate_pages(&cc->migratepages, alloc_migrate_target, |
| NULL, 0, cc->mode, MR_CMA); |
| } |
| if (ret < 0) { |
| putback_movable_pages(&cc->migratepages); |
| return ret; |
| } |
| return 0; |
| } |
| |
| /** |
| * alloc_contig_range() -- tries to allocate given range of pages |
| * @start: start PFN to allocate |
| * @end: one-past-the-last PFN to allocate |
| * @migratetype: migratetype of the underlaying pageblocks (either |
| * #MIGRATE_MOVABLE or #MIGRATE_CMA). All pageblocks |
| * in range must have the same migratetype and it must |
| * be either of the two. |
| * |
| * The PFN range does not have to be pageblock or MAX_ORDER_NR_PAGES |
| * aligned, however it's the caller's responsibility to guarantee that |
| * we are the only thread that changes migrate type of pageblocks the |
| * pages fall in. |
| * |
| * The PFN range must belong to a single zone. |
| * |
| * Returns zero on success or negative error code. On success all |
| * pages which PFN is in [start, end) are allocated for the caller and |
| * need to be freed with free_contig_range(). |
| */ |
| int alloc_contig_range(unsigned long start, unsigned long end, |
| unsigned migratetype) |
| { |
| unsigned long outer_start, outer_end; |
| unsigned int order; |
| int ret = 0; |
| |
| struct compact_control cc = { |
| .nr_migratepages = 0, |
| .order = -1, |
| .zone = page_zone(pfn_to_page(start)), |
| .mode = MIGRATE_SYNC, |
| .ignore_skip_hint = true, |
| }; |
| INIT_LIST_HEAD(&cc.migratepages); |
| |
| /* |
| * What we do here is we mark all pageblocks in range as |
| * MIGRATE_ISOLATE. Because pageblock and max order pages may |
| * have different sizes, and due to the way page allocator |
| * work, we align the range to biggest of the two pages so |
| * that page allocator won't try to merge buddies from |
| * different pageblocks and change MIGRATE_ISOLATE to some |
| * other migration type. |
| * |
| * Once the pageblocks are marked as MIGRATE_ISOLATE, we |
| * migrate the pages from an unaligned range (ie. pages that |
| * we are interested in). This will put all the pages in |
| * range back to page allocator as MIGRATE_ISOLATE. |
| * |
| * When this is done, we take the pages in range from page |
| * allocator removing them from the buddy system. This way |
| * page allocator will never consider using them. |
| * |
| * This lets us mark the pageblocks back as |
| * MIGRATE_CMA/MIGRATE_MOVABLE so that free pages in the |
| * aligned range but not in the unaligned, original range are |
| * put back to page allocator so that buddy can use them. |
| */ |
| |
| ret = start_isolate_page_range(pfn_max_align_down(start), |
| pfn_max_align_up(end), migratetype, |
| false); |
| if (ret) |
| return ret; |
| |
| /* |
| * In case of -EBUSY, we'd like to know which page causes problem. |
| * So, just fall through. We will check it in test_pages_isolated(). |
| */ |
| ret = __alloc_contig_migrate_range(&cc, start, end); |
| if (ret && ret != -EBUSY) |
| goto done; |
| |
| /* |
| * Pages from [start, end) are within a MAX_ORDER_NR_PAGES |
| * aligned blocks that are marked as MIGRATE_ISOLATE. What's |
| * more, all pages in [start, end) are free in page allocator. |
| * What we are going to do is to allocate all pages from |
| * [start, end) (that is remove them from page allocator). |
| * |
| * The only problem is that pages at the beginning and at the |
| * end of interesting range may be not aligned with pages that |
| * page allocator holds, ie. they can be part of higher order |
| * pages. Because of this, we reserve the bigger range and |
| * once this is done free the pages we are not interested in. |
| * |
| * We don't have to hold zone->lock here because the pages are |
| * isolated thus they won't get removed from buddy. |
| */ |
| |
| lru_add_drain_all(); |
| drain_all_pages(cc.zone); |
| |
| order = 0; |
| outer_start = start; |
| while (!PageBuddy(pfn_to_page(outer_start))) { |
| if (++order >= MAX_ORDER) { |
| outer_start = start; |
| break; |
| } |
| outer_start &= ~0UL << order; |
| } |
| |
| if (outer_start != start) { |
| order = page_order(pfn_to_page(outer_start)); |
| |
| /* |
| * outer_start page could be small order buddy page and |
| * it doesn't include start page. Adjust outer_start |
| * in this case to report failed page properly |
| * on tracepoint in test_pages_isolated() |
| */ |
| if (outer_start + (1UL << order) <= start) |
| outer_start = start; |
| } |
| |
| /* Make sure the range is really isolated. */ |
| if (test_pages_isolated(outer_start, end, false)) { |
| pr_info("%s: [%lx, %lx) PFNs busy\n", |
| __func__, outer_start, end); |
| ret = -EBUSY; |
| goto done; |
| } |
| |
| /* Grab isolated pages from freelists. */ |
| outer_end = isolate_freepages_range(&cc, outer_start, end); |
| if (!outer_end) { |
| ret = -EBUSY; |
| goto done; |
| } |
| |
| /* Free head and tail (if any) */ |
| if (start != outer_start) |
| free_contig_range(outer_start, start - outer_start); |
| if (end != outer_end) |
| free_contig_range(end, outer_end - end); |
| |
| done: |
| undo_isolate_page_range(pfn_max_align_down(start), |
| pfn_max_align_up(end), migratetype); |
| return ret; |
| } |
| |
| void free_contig_range(unsigned long pfn, unsigned nr_pages) |
| { |
| unsigned int count = 0; |
| |
| for (; nr_pages--; pfn++) { |
| struct page *page = pfn_to_page(pfn); |
| |
| count += page_count(page) != 1; |
| __free_page(page); |
| } |
| WARN(count != 0, "%d pages are still in use!\n", count); |
| } |
| #endif |
| |
| #ifdef CONFIG_MEMORY_HOTPLUG |
| /* |
| * The zone indicated has a new number of managed_pages; batch sizes and percpu |
| * page high values need to be recalulated. |
| */ |
| void __meminit zone_pcp_update(struct zone *zone) |
| { |
| unsigned cpu; |
| mutex_lock(&pcp_batch_high_lock); |
| for_each_possible_cpu(cpu) |
| pageset_set_high_and_batch(zone, |
| per_cpu_ptr(zone->pageset, cpu)); |
| mutex_unlock(&pcp_batch_high_lock); |
| } |
| #endif |
| |
| void zone_pcp_reset(struct zone *zone) |
| { |
| unsigned long flags; |
| int cpu; |
| struct per_cpu_pageset *pset; |
| |
| /* avoid races with drain_pages() */ |
| local_irq_save(flags); |
| if (zone->pageset != &boot_pageset) { |
| for_each_online_cpu(cpu) { |
| pset = per_cpu_ptr(zone->pageset, cpu); |
| drain_zonestat(zone, pset); |
| } |
| free_percpu(zone->pageset); |
| zone->pageset = &boot_pageset; |
| } |
| local_irq_restore(flags); |
| } |
| |
| #ifdef CONFIG_MEMORY_HOTREMOVE |
| /* |
| * All pages in the range must be in a single zone and isolated |
| * before calling this. |
| */ |
| void |
| __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) |
| { |
| struct page *page; |
| struct zone *zone; |
| unsigned int order, i; |
| unsigned long pfn; |
| unsigned long flags; |
| /* find the first valid pfn */ |
| for (pfn = start_pfn; pfn < end_pfn; pfn++) |
| if (pfn_valid(pfn)) |
| break; |
| if (pfn == end_pfn) |
| return; |
| zone = page_zone(pfn_to_page(pfn)); |
| spin_lock_irqsave(&zone->lock, flags); |
| pfn = start_pfn; |
| while (pfn < end_pfn) { |
| if (!pfn_valid(pfn)) { |
| pfn++; |
| continue; |
| } |
| page = pfn_to_page(pfn); |
| /* |
| * The HWPoisoned page may be not in buddy system, and |
| * page_count() is not 0. |
| */ |
| if (unlikely(!PageBuddy(page) && PageHWPoison(page))) { |
| pfn++; |
| SetPageReserved(page); |
| continue; |
| } |
| |
| BUG_ON(page_count(page)); |
| BUG_ON(!PageBuddy(page)); |
| order = page_order(page); |
| #ifdef CONFIG_DEBUG_VM |
| pr_info("remove from free list %lx %d %lx\n", |
| pfn, 1 << order, end_pfn); |
| #endif |
| list_del(&page->lru); |
| rmv_page_order(page); |
| zone->free_area[order].nr_free--; |
| for (i = 0; i < (1 << order); i++) |
| SetPageReserved((page+i)); |
| pfn += (1 << order); |
| } |
| spin_unlock_irqrestore(&zone->lock, flags); |
| } |
| #endif |
| |
| bool is_free_buddy_page(struct page *page) |
| { |
| struct zone *zone = page_zone(page); |
| unsigned long pfn = page_to_pfn(page); |
| unsigned long flags; |
| unsigned int order; |
| |
| spin_lock_irqsave(&zone->lock, flags); |
| for (order = 0; order < MAX_ORDER; order++) { |
| struct page *page_head = page - (pfn & ((1 << order) - 1)); |
| |
| if (PageBuddy(page_head) && page_order(page_head) >= order) |
| break; |
| } |
| spin_unlock_irqrestore(&zone->lock, flags); |
| |
| return order < MAX_ORDER; |
| } |