page_alloc.c 181.7 KB
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/*
 *  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>
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#include <linux/jiffies.h>
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#include <linux/bootmem.h>
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#include <linux/memblock.h>
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#include <linux/compiler.h>
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#include <linux/kernel.h>
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#include <linux/kmemcheck.h>
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#include <linux/module.h>
#include <linux/suspend.h>
#include <linux/pagevec.h>
#include <linux/blkdev.h>
#include <linux/slab.h>
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#include <linux/ratelimit.h>
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#include <linux/oom.h>
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#include <linux/notifier.h>
#include <linux/topology.h>
#include <linux/sysctl.h>
#include <linux/cpu.h>
#include <linux/cpuset.h>
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#include <linux/memory_hotplug.h>
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#include <linux/nodemask.h>
#include <linux/vmalloc.h>
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#include <linux/vmstat.h>
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#include <linux/mempolicy.h>
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#include <linux/stop_machine.h>
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#include <linux/sort.h>
#include <linux/pfn.h>
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#include <linux/backing-dev.h>
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#include <linux/fault-inject.h>
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#include <linux/page-isolation.h>
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#include <linux/page_cgroup.h>
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#include <linux/debugobjects.h>
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#include <linux/kmemleak.h>
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#include <linux/compaction.h>
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#include <trace/events/kmem.h>
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#include <linux/ftrace_event.h>
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#include <linux/memcontrol.h>
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#include <linux/prefetch.h>
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#include <linux/mm_inline.h>
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#include <linux/migrate.h>
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#include <linux/page-debug-flags.h>
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#include <linux/hugetlb.h>
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#include <linux/sched/rt.h>
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#include <asm/sections.h>
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#include <asm/tlbflush.h>
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#include <asm/div64.h>
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#include "internal.h"

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/* prevent >1 _updater_ of zone percpu pageset ->high and ->batch fields */
static DEFINE_MUTEX(pcp_batch_high_lock);

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#ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
DEFINE_PER_CPU(int, numa_node);
EXPORT_PER_CPU_SYMBOL(numa_node);
#endif

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#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_);
#endif

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/*
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 * Array of node states.
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 */
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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 } },
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#endif
#ifdef CONFIG_MOVABLE_NODE
	[N_MEMORY] = { { [0] = 1UL } },
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#endif
	[N_CPU] = { { [0] = 1UL } },
#endif	/* NUMA */
};
EXPORT_SYMBOL(node_states);

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/* Protect totalram_pages and zone->managed_pages */
static DEFINE_SPINLOCK(managed_page_count_lock);

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unsigned long totalram_pages __read_mostly;
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unsigned long totalreserve_pages __read_mostly;
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/*
 * When calculating the number of globally allowed dirty pages, there
 * is a certain number of per-zone reserves that should not be
 * considered dirtyable memory.  This is the sum of those reserves
 * over all existing zones that contribute dirtyable memory.
 */
unsigned long dirty_balance_reserve __read_mostly;

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int percpu_pagelist_fraction;
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gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK;
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#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).
 */
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static gfp_t saved_gfp_mask;

void pm_restore_gfp_mask(void)
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{
	WARN_ON(!mutex_is_locked(&pm_mutex));
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	if (saved_gfp_mask) {
		gfp_allowed_mask = saved_gfp_mask;
		saved_gfp_mask = 0;
	}
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}

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void pm_restrict_gfp_mask(void)
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{
	WARN_ON(!mutex_is_locked(&pm_mutex));
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	WARN_ON(saved_gfp_mask);
	saved_gfp_mask = gfp_allowed_mask;
	gfp_allowed_mask &= ~GFP_IOFS;
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}
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bool pm_suspended_storage(void)
{
	if ((gfp_allowed_mask & GFP_IOFS) == GFP_IOFS)
		return false;
	return true;
}
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#endif /* CONFIG_PM_SLEEP */

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#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
int pageblock_order __read_mostly;
#endif

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static void __free_pages_ok(struct page *page, unsigned int order);
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/*
 * 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 (224M+784M)/256 of ram reserved in ZONE_DMA
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 *
 * TBD: should special case ZONE_DMA32 machines here - in those we normally
 * don't need any ZONE_NORMAL reservation
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 */
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int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = {
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#ifdef CONFIG_ZONE_DMA
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	 256,
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#endif
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#ifdef CONFIG_ZONE_DMA32
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	 256,
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#endif
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#ifdef CONFIG_HIGHMEM
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	 32,
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#endif
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	 32,
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};
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EXPORT_SYMBOL(totalram_pages);

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static char * const zone_names[MAX_NR_ZONES] = {
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#ifdef CONFIG_ZONE_DMA
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	 "DMA",
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#endif
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#ifdef CONFIG_ZONE_DMA32
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	 "DMA32",
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#endif
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	 "Normal",
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#ifdef CONFIG_HIGHMEM
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	 "HighMem",
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#endif
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	 "Movable",
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};

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int min_free_kbytes = 1024;
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int user_min_free_kbytes = -1;
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static unsigned long __meminitdata nr_kernel_pages;
static unsigned long __meminitdata nr_all_pages;
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static unsigned long __meminitdata dma_reserve;
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#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];

/* 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 */
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#if MAX_NUMNODES > 1
int nr_node_ids __read_mostly = MAX_NUMNODES;
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int nr_online_nodes __read_mostly = 1;
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EXPORT_SYMBOL(nr_node_ids);
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EXPORT_SYMBOL(nr_online_nodes);
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#endif

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int page_group_by_mobility_disabled __read_mostly;

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void set_pageblock_migratetype(struct page *page, int migratetype)
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{
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	if (unlikely(page_group_by_mobility_disabled &&
		     migratetype < MIGRATE_PCPTYPES))
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		migratetype = MIGRATE_UNMOVABLE;

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	set_pageblock_flags_group(page, (unsigned long)migratetype,
					PB_migrate, PB_migrate_end);
}

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bool oom_killer_disabled __read_mostly;

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#ifdef CONFIG_DEBUG_VM
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static int page_outside_zone_boundaries(struct zone *zone, struct page *page)
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{
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	int ret = 0;
	unsigned seq;
	unsigned long pfn = page_to_pfn(page);
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	unsigned long sp, start_pfn;
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	do {
		seq = zone_span_seqbegin(zone);
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		start_pfn = zone->zone_start_pfn;
		sp = zone->spanned_pages;
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		if (!zone_spans_pfn(zone, pfn))
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			ret = 1;
	} while (zone_span_seqretry(zone, seq));

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	if (ret)
		pr_err("page %lu outside zone [ %lu - %lu ]\n",
			pfn, start_pfn, start_pfn + sp);

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	return ret;
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}

static int page_is_consistent(struct zone *zone, struct page *page)
{
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	if (!pfn_valid_within(page_to_pfn(page)))
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		return 0;
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	if (zone != page_zone(page))
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		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))
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		return 1;
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	if (!page_is_consistent(zone, page))
		return 1;

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	return 0;
}
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#else
static inline int bad_range(struct zone *zone, struct page *page)
{
	return 0;
}
#endif

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static void bad_page(struct page *page, const char *reason,
		unsigned long bad_flags)
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{
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	static unsigned long resume;
	static unsigned long nr_shown;
	static unsigned long nr_unshown;

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	/* Don't complain about poisoned pages */
	if (PageHWPoison(page)) {
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		page_mapcount_reset(page); /* remove PageBuddy */
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		return;
	}

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	/*
	 * 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) {
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			printk(KERN_ALERT
			      "BUG: Bad page state: %lu messages suppressed\n",
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				nr_unshown);
			nr_unshown = 0;
		}
		nr_shown = 0;
	}
	if (nr_shown++ == 0)
		resume = jiffies + 60 * HZ;

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	printk(KERN_ALERT "BUG: Bad page state in process %s  pfn:%05lx\n",
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		current->comm, page_to_pfn(page));
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	dump_page_badflags(page, reason, bad_flags);
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	print_modules();
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	dump_stack();
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out:
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	/* Leave bad fields for debug, except PageBuddy could make trouble */
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	page_mapcount_reset(page); /* remove PageBuddy */
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	add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
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}

/*
 * Higher-order pages are called "compound pages".  They are structured thusly:
 *
 * The first PAGE_SIZE page is called the "head page".
 *
 * The remaining PAGE_SIZE pages are called "tail pages".
 *
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 * All pages have PG_compound set.  All tail pages have their ->first_page
 * pointing at the head page.
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 *
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 * The first tail page's ->lru.next holds the address of the compound page's
 * put_page() function.  Its ->lru.prev holds the order of allocation.
 * This usage means that zero-order pages may not be compound.
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 */
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static void free_compound_page(struct page *page)
{
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	__free_pages_ok(page, compound_order(page));
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}

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void prep_compound_page(struct page *page, unsigned long order)
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{
	int i;
	int nr_pages = 1 << order;

	set_compound_page_dtor(page, free_compound_page);
	set_compound_order(page, order);
	__SetPageHead(page);
	for (i = 1; i < nr_pages; i++) {
		struct page *p = page + i;
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		set_page_count(p, 0);
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		p->first_page = page;
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		/* Make sure p->first_page is always valid for PageTail() */
		smp_wmb();
		__SetPageTail(p);
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	}
}

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/* update __split_huge_page_refcount if you change this function */
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static int destroy_compound_page(struct page *page, unsigned long order)
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{
	int i;
	int nr_pages = 1 << order;
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	int bad = 0;
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	if (unlikely(compound_order(page) != order)) {
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		bad_page(page, "wrong compound order", 0);
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		bad++;
	}
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	__ClearPageHead(page);
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	for (i = 1; i < nr_pages; i++) {
		struct page *p = page + i;
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		if (unlikely(!PageTail(p))) {
			bad_page(page, "PageTail not set", 0);
			bad++;
		} else if (unlikely(p->first_page != page)) {
			bad_page(page, "first_page not consistent", 0);
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			bad++;
		}
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		__ClearPageTail(p);
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	}
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	return bad;
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}

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static inline void prep_zero_page(struct page *page, int order, gfp_t gfp_flags)
{
	int i;

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	/*
	 * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO
	 * and __GFP_HIGHMEM from hard or soft interrupt context.
	 */
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	VM_BUG_ON((gfp_flags & __GFP_HIGHMEM) && in_interrupt());
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	for (i = 0; i < (1 << order); i++)
		clear_highpage(page + i);
}

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#ifdef CONFIG_DEBUG_PAGEALLOC
unsigned int _debug_guardpage_minorder;

static int __init debug_guardpage_minorder_setup(char *buf)
{
	unsigned long res;

	if (kstrtoul(buf, 10, &res) < 0 ||  res > MAX_ORDER / 2) {
		printk(KERN_ERR "Bad debug_guardpage_minorder value\n");
		return 0;
	}
	_debug_guardpage_minorder = res;
	printk(KERN_INFO "Setting debug_guardpage_minorder to %lu\n", res);
	return 0;
}
__setup("debug_guardpage_minorder=", debug_guardpage_minorder_setup);

static inline void set_page_guard_flag(struct page *page)
{
	__set_bit(PAGE_DEBUG_FLAG_GUARD, &page->debug_flags);
}

static inline void clear_page_guard_flag(struct page *page)
{
	__clear_bit(PAGE_DEBUG_FLAG_GUARD, &page->debug_flags);
}
#else
static inline void set_page_guard_flag(struct page *page) { }
static inline void clear_page_guard_flag(struct page *page) { }
#endif

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static inline void set_page_order(struct page *page, int order)
{
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	set_page_private(page, order);
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	__SetPageBuddy(page);
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}

static inline void rmv_page_order(struct page *page)
{
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	__ClearPageBuddy(page);
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	set_page_private(page, 0);
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}

/*
 * Locate the struct page for both the matching buddy in our
 * pair (buddy1) and the combined O(n+1) page they form (page).
 *
 * 1) Any buddy B1 will have an order O twin B2 which satisfies
 * the following equation:
 *     B2 = B1 ^ (1 << O)
 * For example, if the starting buddy (buddy2) is #8 its order
 * 1 buddy is #10:
 *     B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
 *
 * 2) Any buddy B will have an order O+1 parent P which
 * satisfies the following equation:
 *     P = B & ~(1 << O)
 *
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 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
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 */
static inline unsigned long
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__find_buddy_index(unsigned long page_idx, unsigned int order)
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{
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	return page_idx ^ (1 << order);
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}

/*
 * This function checks whether a page is free && is the buddy
 * we can do coalesce a page and its buddy if
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 * (a) the buddy is not in a hole &&
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 * (b) the buddy is in the buddy system &&
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 * (c) a page and its buddy have the same order &&
 * (d) a page and its buddy are in the same zone.
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 *
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 * 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.
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 *
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 * For recording page's order, we use page_private(page).
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 */
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static inline int page_is_buddy(struct page *page, struct page *buddy,
								int order)
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{
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	if (!pfn_valid_within(page_to_pfn(buddy)))
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		return 0;

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	if (page_zone_id(page) != page_zone_id(buddy))
		return 0;

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	if (page_is_guard(buddy) && page_order(buddy) == order) {
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		VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy);
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		return 1;
	}

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	if (PageBuddy(buddy) && page_order(buddy) == order) {
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		VM_BUG_ON_PAGE(page_count(buddy) != 0, buddy);
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		return 1;
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	}
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	return 0;
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}

/*
 * 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
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 * 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.
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 * So when we are allocating or freeing one, we can derive the state of the
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 * other.  That is, if we allocate a small block, and both were
 * free, the remainder of the region must be split into blocks.
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 * If a block is freed, and its buddy is also free, then this
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 * triggers coalescing into a block of larger size.
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 *
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 * -- nyc
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 */

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static inline void __free_one_page(struct page *page,
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		struct zone *zone, unsigned int order,
		int migratetype)
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{
	unsigned long page_idx;
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	unsigned long combined_idx;
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	unsigned long uninitialized_var(buddy_idx);
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	struct page *buddy;
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	VM_BUG_ON(!zone_is_initialized(zone));

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	if (unlikely(PageCompound(page)))
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		if (unlikely(destroy_compound_page(page, order)))
			return;
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	VM_BUG_ON(migratetype == -1);

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568 569
	page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1);

570 571
	VM_BUG_ON_PAGE(page_idx & ((1 << order) - 1), page);
	VM_BUG_ON_PAGE(bad_range(zone, page), page);
L
Linus Torvalds 已提交
572 573

	while (order < MAX_ORDER-1) {
574 575
		buddy_idx = __find_buddy_index(page_idx, order);
		buddy = page + (buddy_idx - page_idx);
576
		if (!page_is_buddy(page, buddy, order))
577
			break;
578 579 580 581 582 583 584
		/*
		 * 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_flag(buddy);
			set_page_private(page, 0);
585 586
			__mod_zone_freepage_state(zone, 1 << order,
						  migratetype);
587 588 589 590 591
		} else {
			list_del(&buddy->lru);
			zone->free_area[order].nr_free--;
			rmv_page_order(buddy);
		}
592
		combined_idx = buddy_idx & page_idx;
L
Linus Torvalds 已提交
593 594 595 596 597
		page = page + (combined_idx - page_idx);
		page_idx = combined_idx;
		order++;
	}
	set_page_order(page, order);
598 599 600 601 602 603 604 605 606

	/*
	 * 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
	 */
607
	if ((order < MAX_ORDER-2) && pfn_valid_within(page_to_pfn(buddy))) {
608
		struct page *higher_page, *higher_buddy;
609 610 611
		combined_idx = buddy_idx & page_idx;
		higher_page = page + (combined_idx - page_idx);
		buddy_idx = __find_buddy_index(combined_idx, order + 1);
612
		higher_buddy = higher_page + (buddy_idx - combined_idx);
613 614 615 616 617 618 619 620 621
		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:
L
Linus Torvalds 已提交
622 623 624
	zone->free_area[order].nr_free++;
}

N
Nick Piggin 已提交
625
static inline int free_pages_check(struct page *page)
L
Linus Torvalds 已提交
626
{
627
	const char *bad_reason = NULL;
628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643
	unsigned long bad_flags = 0;

	if (unlikely(page_mapcount(page)))
		bad_reason = "nonzero mapcount";
	if (unlikely(page->mapping != NULL))
		bad_reason = "non-NULL mapping";
	if (unlikely(atomic_read(&page->_count) != 0))
		bad_reason = "nonzero _count";
	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;
	}
	if (unlikely(mem_cgroup_bad_page_check(page)))
		bad_reason = "cgroup check failed";
	if (unlikely(bad_reason)) {
		bad_page(page, bad_reason, bad_flags);
644
		return 1;
645
	}
646
	page_cpupid_reset_last(page);
647 648 649
	if (page->flags & PAGE_FLAGS_CHECK_AT_PREP)
		page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP;
	return 0;
L
Linus Torvalds 已提交
650 651 652
}

/*
653
 * Frees a number of pages from the PCP lists
L
Linus Torvalds 已提交
654
 * Assumes all pages on list are in same zone, and of same order.
655
 * count is the number of pages to free.
L
Linus Torvalds 已提交
656 657 658 659 660 661 662
 *
 * 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.
 */
663 664
static void free_pcppages_bulk(struct zone *zone, int count,
					struct per_cpu_pages *pcp)
L
Linus Torvalds 已提交
665
{
666
	int migratetype = 0;
667
	int batch_free = 0;
668
	int to_free = count;
669

N
Nick Piggin 已提交
670
	spin_lock(&zone->lock);
L
Linus Torvalds 已提交
671
	zone->pages_scanned = 0;
672

673
	while (to_free) {
N
Nick Piggin 已提交
674
		struct page *page;
675 676 677
		struct list_head *list;

		/*
678 679 680 681 682
		 * 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
683 684
		 */
		do {
685
			batch_free++;
686 687 688 689
			if (++migratetype == MIGRATE_PCPTYPES)
				migratetype = 0;
			list = &pcp->lists[migratetype];
		} while (list_empty(list));
N
Nick Piggin 已提交
690

691 692 693 694
		/* This is the only non-empty list. Free them all. */
		if (batch_free == MIGRATE_PCPTYPES)
			batch_free = to_free;

695
		do {
696 697
			int mt;	/* migratetype of the to-be-freed page */

698 699 700
			page = list_entry(list->prev, struct page, lru);
			/* must delete as __free_one_page list manipulates */
			list_del(&page->lru);
701
			mt = get_freepage_migratetype(page);
702
			/* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */
703 704
			__free_one_page(page, zone, 0, mt);
			trace_mm_page_pcpu_drain(page, 0, mt);
705
			if (likely(!is_migrate_isolate_page(page))) {
706 707 708 709
				__mod_zone_page_state(zone, NR_FREE_PAGES, 1);
				if (is_migrate_cma(mt))
					__mod_zone_page_state(zone, NR_FREE_CMA_PAGES, 1);
			}
710
		} while (--to_free && --batch_free && !list_empty(list));
L
Linus Torvalds 已提交
711
	}
N
Nick Piggin 已提交
712
	spin_unlock(&zone->lock);
L
Linus Torvalds 已提交
713 714
}

715 716
static void free_one_page(struct zone *zone, struct page *page, int order,
				int migratetype)
L
Linus Torvalds 已提交
717
{
718 719
	spin_lock(&zone->lock);
	zone->pages_scanned = 0;
720

721
	__free_one_page(page, zone, order, migratetype);
722
	if (unlikely(!is_migrate_isolate(migratetype)))
723
		__mod_zone_freepage_state(zone, 1 << order, migratetype);
724
	spin_unlock(&zone->lock);
N
Nick Piggin 已提交
725 726
}

727
static bool free_pages_prepare(struct page *page, unsigned int order)
N
Nick Piggin 已提交
728
{
L
Linus Torvalds 已提交
729
	int i;
730
	int bad = 0;
L
Linus Torvalds 已提交
731

732
	trace_mm_page_free(page, order);
733 734
	kmemcheck_free_shadow(page, order);

A
Andrea Arcangeli 已提交
735 736 737 738
	if (PageAnon(page))
		page->mapping = NULL;
	for (i = 0; i < (1 << order); i++)
		bad += free_pages_check(page + i);
739
	if (bad)
740
		return false;
741

742
	if (!PageHighMem(page)) {
743 744
		debug_check_no_locks_freed(page_address(page),
					   PAGE_SIZE << order);
745 746 747
		debug_check_no_obj_freed(page_address(page),
					   PAGE_SIZE << order);
	}
N
Nick Piggin 已提交
748
	arch_free_page(page, order);
N
Nick Piggin 已提交
749
	kernel_map_pages(page, 1 << order, 0);
N
Nick Piggin 已提交
750

751 752 753 754 755 756
	return true;
}

static void __free_pages_ok(struct page *page, unsigned int order)
{
	unsigned long flags;
M
Minchan Kim 已提交
757
	int migratetype;
758 759 760 761

	if (!free_pages_prepare(page, order))
		return;

N
Nick Piggin 已提交
762
	local_irq_save(flags);
763
	__count_vm_events(PGFREE, 1 << order);
M
Minchan Kim 已提交
764 765 766
	migratetype = get_pageblock_migratetype(page);
	set_freepage_migratetype(page, migratetype);
	free_one_page(page_zone(page), page, order, migratetype);
N
Nick Piggin 已提交
767
	local_irq_restore(flags);
L
Linus Torvalds 已提交
768 769
}

770
void __init __free_pages_bootmem(struct page *page, unsigned int order)
771
{
772
	unsigned int nr_pages = 1 << order;
773
	struct page *p = page;
774
	unsigned int loop;
775

776 777 778
	prefetchw(p);
	for (loop = 0; loop < (nr_pages - 1); loop++, p++) {
		prefetchw(p + 1);
779 780
		__ClearPageReserved(p);
		set_page_count(p, 0);
781
	}
782 783
	__ClearPageReserved(p);
	set_page_count(p, 0);
784

785
	page_zone(page)->managed_pages += nr_pages;
786 787
	set_page_refcounted(page);
	__free_pages(page, order);
788 789
}

790
#ifdef CONFIG_CMA
791
/* Free whole pageblock and set its migration type to MIGRATE_CMA. */
792 793 794 795 796 797 798 799 800 801 802 803 804
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_page_refcounted(page);
	set_pageblock_migratetype(page, MIGRATE_CMA);
	__free_pages(page, pageblock_order);
805
	adjust_managed_page_count(page, pageblock_nr_pages);
806 807
}
#endif
L
Linus Torvalds 已提交
808 809 810 811 812 813 814 815 816 817 818 819 820

/*
 * 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.
 *
821
 * -- nyc
L
Linus Torvalds 已提交
822
 */
N
Nick Piggin 已提交
823
static inline void expand(struct zone *zone, struct page *page,
824 825
	int low, int high, struct free_area *area,
	int migratetype)
L
Linus Torvalds 已提交
826 827 828 829 830 831 832
{
	unsigned long size = 1 << high;

	while (high > low) {
		area--;
		high--;
		size >>= 1;
833
		VM_BUG_ON_PAGE(bad_range(zone, &page[size]), &page[size]);
834 835 836 837 838 839 840 841 842 843 844 845 846

#ifdef CONFIG_DEBUG_PAGEALLOC
		if (high < debug_guardpage_minorder()) {
			/*
			 * 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
			 */
			INIT_LIST_HEAD(&page[size].lru);
			set_page_guard_flag(&page[size]);
			set_page_private(&page[size], high);
			/* Guard pages are not available for any usage */
847 848
			__mod_zone_freepage_state(zone, -(1 << high),
						  migratetype);
849 850 851
			continue;
		}
#endif
852
		list_add(&page[size].lru, &area->free_list[migratetype]);
L
Linus Torvalds 已提交
853 854 855 856 857 858 859 860
		area->nr_free++;
		set_page_order(&page[size], high);
	}
}

/*
 * This page is about to be returned from the page allocator
 */
861
static inline int check_new_page(struct page *page)
L
Linus Torvalds 已提交
862
{
863
	const char *bad_reason = NULL;
864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879
	unsigned long bad_flags = 0;

	if (unlikely(page_mapcount(page)))
		bad_reason = "nonzero mapcount";
	if (unlikely(page->mapping != NULL))
		bad_reason = "non-NULL mapping";
	if (unlikely(atomic_read(&page->_count) != 0))
		bad_reason = "nonzero _count";
	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;
	}
	if (unlikely(mem_cgroup_bad_page_check(page)))
		bad_reason = "cgroup check failed";
	if (unlikely(bad_reason)) {
		bad_page(page, bad_reason, bad_flags);
880
		return 1;
881
	}
882 883 884 885 886 887 888 889 890 891 892 893
	return 0;
}

static int prep_new_page(struct page *page, int order, gfp_t gfp_flags)
{
	int i;

	for (i = 0; i < (1 << order); i++) {
		struct page *p = page + i;
		if (unlikely(check_new_page(p)))
			return 1;
	}
894

H
Hugh Dickins 已提交
895
	set_page_private(page, 0);
896
	set_page_refcounted(page);
N
Nick Piggin 已提交
897 898

	arch_alloc_page(page, order);
L
Linus Torvalds 已提交
899
	kernel_map_pages(page, 1 << order, 1);
N
Nick Piggin 已提交
900 901 902 903 904 905 906

	if (gfp_flags & __GFP_ZERO)
		prep_zero_page(page, order, gfp_flags);

	if (order && (gfp_flags & __GFP_COMP))
		prep_compound_page(page, order);

907
	return 0;
L
Linus Torvalds 已提交
908 909
}

910 911 912 913
/*
 * Go through the free lists for the given migratetype and remove
 * the smallest available page from the freelists
 */
914 915
static inline
struct page *__rmqueue_smallest(struct zone *zone, unsigned int order,
916 917 918
						int migratetype)
{
	unsigned int current_order;
919
	struct free_area *area;
920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940
	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]);
		if (list_empty(&area->free_list[migratetype]))
			continue;

		page = list_entry(area->free_list[migratetype].next,
							struct page, lru);
		list_del(&page->lru);
		rmv_page_order(page);
		area->nr_free--;
		expand(zone, page, order, current_order, area, migratetype);
		return page;
	}

	return NULL;
}


941 942 943 944
/*
 * This array describes the order lists are fallen back to when
 * the free lists for the desirable migrate type are depleted
 */
945 946 947 948 949 950 951 952 953
static int fallbacks[MIGRATE_TYPES][4] = {
	[MIGRATE_UNMOVABLE]   = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE,     MIGRATE_RESERVE },
	[MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE,   MIGRATE_MOVABLE,     MIGRATE_RESERVE },
#ifdef CONFIG_CMA
	[MIGRATE_MOVABLE]     = { MIGRATE_CMA,         MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE },
	[MIGRATE_CMA]         = { MIGRATE_RESERVE }, /* Never used */
#else
	[MIGRATE_MOVABLE]     = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE,   MIGRATE_RESERVE },
#endif
954
	[MIGRATE_RESERVE]     = { MIGRATE_RESERVE }, /* Never used */
955
#ifdef CONFIG_MEMORY_ISOLATION
956
	[MIGRATE_ISOLATE]     = { MIGRATE_RESERVE }, /* Never used */
957
#endif
958 959
};

960 961
/*
 * Move the free pages in a range to the free lists of the requested type.
962
 * Note that start_page and end_pages are not aligned on a pageblock
963 964
 * boundary. If alignment is required, use move_freepages_block()
 */
965
int move_freepages(struct zone *zone,
A
Adrian Bunk 已提交
966 967
			  struct page *start_page, struct page *end_page,
			  int migratetype)
968 969 970
{
	struct page *page;
	unsigned long order;
971
	int pages_moved = 0;
972 973 974 975 976 977 978

#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
M
Mel Gorman 已提交
979
	 * grouping pages by mobility
980 981 982 983 984
	 */
	BUG_ON(page_zone(start_page) != page_zone(end_page));
#endif

	for (page = start_page; page <= end_page;) {
985
		/* Make sure we are not inadvertently changing nodes */
986
		VM_BUG_ON_PAGE(page_to_nid(page) != zone_to_nid(zone), page);
987

988 989 990 991 992 993 994 995 996 997 998
		if (!pfn_valid_within(page_to_pfn(page))) {
			page++;
			continue;
		}

		if (!PageBuddy(page)) {
			page++;
			continue;
		}

		order = page_order(page);
999 1000
		list_move(&page->lru,
			  &zone->free_area[order].free_list[migratetype]);
M
Minchan Kim 已提交
1001
		set_freepage_migratetype(page, migratetype);
1002
		page += 1 << order;
1003
		pages_moved += 1 << order;
1004 1005
	}

1006
	return pages_moved;
1007 1008
}

1009
int move_freepages_block(struct zone *zone, struct page *page,
1010
				int migratetype)
1011 1012 1013 1014 1015
{
	unsigned long start_pfn, end_pfn;
	struct page *start_page, *end_page;

	start_pfn = page_to_pfn(page);
1016
	start_pfn = start_pfn & ~(pageblock_nr_pages-1);
1017
	start_page = pfn_to_page(start_pfn);
1018 1019
	end_page = start_page + pageblock_nr_pages - 1;
	end_pfn = start_pfn + pageblock_nr_pages - 1;
1020 1021

	/* Do not cross zone boundaries */
1022
	if (!zone_spans_pfn(zone, start_pfn))
1023
		start_page = page;
1024
	if (!zone_spans_pfn(zone, end_pfn))
1025 1026 1027 1028 1029
		return 0;

	return move_freepages(zone, start_page, end_page, migratetype);
}

1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040
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;
	}
}

1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057
/*
 * If breaking a large block of pages, move all free pages to the preferred
 * allocation list. If falling back for a reclaimable kernel allocation, be
 * more aggressive about taking ownership of free pages.
 *
 * On the other hand, never change migration type of MIGRATE_CMA pageblocks
 * nor move CMA pages to different free lists. We don't want unmovable pages
 * to be allocated from MIGRATE_CMA areas.
 *
 * Returns the new migratetype of the pageblock (or the same old migratetype
 * if it was unchanged).
 */
static int try_to_steal_freepages(struct zone *zone, struct page *page,
				  int start_type, int fallback_type)
{
	int current_order = page_order(page);

1058 1059 1060 1061
	/*
	 * When borrowing from MIGRATE_CMA, we need to release the excess
	 * buddy pages to CMA itself.
	 */
1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090
	if (is_migrate_cma(fallback_type))
		return fallback_type;

	/* Take ownership for orders >= pageblock_order */
	if (current_order >= pageblock_order) {
		change_pageblock_range(page, current_order, start_type);
		return start_type;
	}

	if (current_order >= pageblock_order / 2 ||
	    start_type == MIGRATE_RECLAIMABLE ||
	    page_group_by_mobility_disabled) {
		int pages;

		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);
			return start_type;
		}

	}

	return fallback_type;
}

1091
/* Remove an element from the buddy allocator from the fallback list */
1092 1093
static inline struct page *
__rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
1094
{
1095
	struct free_area *area;
1096 1097
	int current_order;
	struct page *page;
1098
	int migratetype, new_type, i;
1099 1100 1101 1102

	/* Find the largest possible block of pages in the other list */
	for (current_order = MAX_ORDER-1; current_order >= order;
						--current_order) {
1103
		for (i = 0;; i++) {
1104 1105
			migratetype = fallbacks[start_migratetype][i];

1106 1107
			/* MIGRATE_RESERVE handled later if necessary */
			if (migratetype == MIGRATE_RESERVE)
1108
				break;
M
Mel Gorman 已提交
1109

1110 1111 1112 1113 1114 1115 1116 1117
			area = &(zone->free_area[current_order]);
			if (list_empty(&area->free_list[migratetype]))
				continue;

			page = list_entry(area->free_list[migratetype].next,
					struct page, lru);
			area->nr_free--;

1118 1119 1120
			new_type = try_to_steal_freepages(zone, page,
							  start_migratetype,
							  migratetype);
1121 1122 1123 1124 1125

			/* Remove the page from the freelists */
			list_del(&page->lru);
			rmv_page_order(page);

1126
			expand(zone, page, order, current_order, area,
1127
			       new_type);
1128

1129 1130
			trace_mm_page_alloc_extfrag(page, order, current_order,
				start_migratetype, migratetype, new_type);
1131

1132 1133 1134 1135
			return page;
		}
	}

1136
	return NULL;
1137 1138
}

1139
/*
L
Linus Torvalds 已提交
1140 1141 1142
 * Do the hard work of removing an element from the buddy allocator.
 * Call me with the zone->lock already held.
 */
1143 1144
static struct page *__rmqueue(struct zone *zone, unsigned int order,
						int migratetype)
L
Linus Torvalds 已提交
1145 1146 1147
{
	struct page *page;

1148
retry_reserve:
1149
	page = __rmqueue_smallest(zone, order, migratetype);
1150

1151
	if (unlikely(!page) && migratetype != MIGRATE_RESERVE) {
1152
		page = __rmqueue_fallback(zone, order, migratetype);
1153

1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164
		/*
		 * Use MIGRATE_RESERVE rather than fail an allocation. goto
		 * is used because __rmqueue_smallest is an inline function
		 * and we want just one call site
		 */
		if (!page) {
			migratetype = MIGRATE_RESERVE;
			goto retry_reserve;
		}
	}

1165
	trace_mm_page_alloc_zone_locked(page, order, migratetype);
1166
	return page;
L
Linus Torvalds 已提交
1167 1168
}

1169
/*
L
Linus Torvalds 已提交
1170 1171 1172 1173
 * 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.
 */
1174
static int rmqueue_bulk(struct zone *zone, unsigned int order,
1175
			unsigned long count, struct list_head *list,
1176
			int migratetype, int cold)
L
Linus Torvalds 已提交
1177
{
1178
	int mt = migratetype, i;
1179

N
Nick Piggin 已提交
1180
	spin_lock(&zone->lock);
L
Linus Torvalds 已提交
1181
	for (i = 0; i < count; ++i) {
1182
		struct page *page = __rmqueue(zone, order, migratetype);
N
Nick Piggin 已提交
1183
		if (unlikely(page == NULL))
L
Linus Torvalds 已提交
1184
			break;
1185 1186 1187 1188 1189 1190 1191 1192 1193 1194

		/*
		 * 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.
		 */
1195 1196 1197 1198
		if (likely(cold == 0))
			list_add(&page->lru, list);
		else
			list_add_tail(&page->lru, list);
1199 1200
		if (IS_ENABLED(CONFIG_CMA)) {
			mt = get_pageblock_migratetype(page);
1201
			if (!is_migrate_cma(mt) && !is_migrate_isolate(mt))
1202 1203
				mt = migratetype;
		}
1204
		set_freepage_migratetype(page, mt);
1205
		list = &page->lru;
1206 1207 1208
		if (is_migrate_cma(mt))
			__mod_zone_page_state(zone, NR_FREE_CMA_PAGES,
					      -(1 << order));
L
Linus Torvalds 已提交
1209
	}
1210
	__mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order));
N
Nick Piggin 已提交
1211
	spin_unlock(&zone->lock);
N
Nick Piggin 已提交
1212
	return i;
L
Linus Torvalds 已提交
1213 1214
}

1215
#ifdef CONFIG_NUMA
1216
/*
1217 1218 1219 1220
 * Called from the vmstat counter updater to drain pagesets of this
 * currently executing processor on remote nodes after they have
 * expired.
 *
1221 1222
 * Note that this function must be called with the thread pinned to
 * a single processor.
1223
 */
1224
void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
1225 1226
{
	unsigned long flags;
1227
	int to_drain;
1228
	unsigned long batch;
1229

1230
	local_irq_save(flags);
1231 1232 1233
	batch = ACCESS_ONCE(pcp->batch);
	if (pcp->count >= batch)
		to_drain = batch;
1234 1235
	else
		to_drain = pcp->count;
1236 1237 1238 1239
	if (to_drain > 0) {
		free_pcppages_bulk(zone, to_drain, pcp);
		pcp->count -= to_drain;
	}
1240
	local_irq_restore(flags);
1241 1242 1243
}
#endif

1244 1245 1246 1247 1248 1249 1250 1251
/*
 * Drain pages of 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)
L
Linus Torvalds 已提交
1252
{
N
Nick Piggin 已提交
1253
	unsigned long flags;
L
Linus Torvalds 已提交
1254 1255
	struct zone *zone;

1256
	for_each_populated_zone(zone) {
L
Linus Torvalds 已提交
1257
		struct per_cpu_pageset *pset;
1258
		struct per_cpu_pages *pcp;
L
Linus Torvalds 已提交
1259

1260 1261
		local_irq_save(flags);
		pset = per_cpu_ptr(zone->pageset, cpu);
1262 1263

		pcp = &pset->pcp;
1264 1265 1266 1267
		if (pcp->count) {
			free_pcppages_bulk(zone, pcp->count, pcp);
			pcp->count = 0;
		}
1268
		local_irq_restore(flags);
L
Linus Torvalds 已提交
1269 1270 1271
	}
}

1272 1273 1274 1275 1276 1277 1278 1279 1280
/*
 * Spill all of this CPU's per-cpu pages back into the buddy allocator.
 */
void drain_local_pages(void *arg)
{
	drain_pages(smp_processor_id());
}

/*
1281 1282 1283 1284 1285 1286 1287
 * Spill all the per-cpu pages from all CPUs back into the buddy allocator.
 *
 * 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().
1288 1289 1290
 */
void drain_all_pages(void)
{
1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321
	int cpu;
	struct per_cpu_pageset *pcp;
	struct zone *zone;

	/*
	 * 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) {
		bool has_pcps = false;
		for_each_populated_zone(zone) {
			pcp = per_cpu_ptr(zone->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, drain_local_pages, NULL, 1);
1322 1323
}

1324
#ifdef CONFIG_HIBERNATION
L
Linus Torvalds 已提交
1325 1326 1327

void mark_free_pages(struct zone *zone)
{
1328 1329
	unsigned long pfn, max_zone_pfn;
	unsigned long flags;
1330
	int order, t;
L
Linus Torvalds 已提交
1331 1332
	struct list_head *curr;

1333
	if (zone_is_empty(zone))
L
Linus Torvalds 已提交
1334 1335 1336
		return;

	spin_lock_irqsave(&zone->lock, flags);
1337

1338
	max_zone_pfn = zone_end_pfn(zone);
1339 1340 1341 1342
	for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
		if (pfn_valid(pfn)) {
			struct page *page = pfn_to_page(pfn);

1343 1344
			if (!swsusp_page_is_forbidden(page))
				swsusp_unset_page_free(page);
1345
		}
L
Linus Torvalds 已提交
1346

1347 1348
	for_each_migratetype_order(order, t) {
		list_for_each(curr, &zone->free_area[order].free_list[t]) {
1349
			unsigned long i;
L
Linus Torvalds 已提交
1350

1351 1352
			pfn = page_to_pfn(list_entry(curr, struct page, lru));
			for (i = 0; i < (1UL << order); i++)
1353
				swsusp_set_page_free(pfn_to_page(pfn + i));
1354
		}
1355
	}
L
Linus Torvalds 已提交
1356 1357
	spin_unlock_irqrestore(&zone->lock, flags);
}
1358
#endif /* CONFIG_PM */
L
Linus Torvalds 已提交
1359 1360 1361

/*
 * Free a 0-order page
L
Li Hong 已提交
1362
 * cold == 1 ? free a cold page : free a hot page
L
Linus Torvalds 已提交
1363
 */
L
Li Hong 已提交
1364
void free_hot_cold_page(struct page *page, int cold)
L
Linus Torvalds 已提交
1365 1366 1367 1368
{
	struct zone *zone = page_zone(page);
	struct per_cpu_pages *pcp;
	unsigned long flags;
1369
	int migratetype;
L
Linus Torvalds 已提交
1370

1371
	if (!free_pages_prepare(page, 0))
1372 1373
		return;

1374
	migratetype = get_pageblock_migratetype(page);
1375
	set_freepage_migratetype(page, migratetype);
L
Linus Torvalds 已提交
1376
	local_irq_save(flags);
1377
	__count_vm_event(PGFREE);
1378

1379 1380 1381 1382 1383 1384 1385 1386
	/*
	 * 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) {
1387
		if (unlikely(is_migrate_isolate(migratetype))) {
1388 1389 1390 1391 1392 1393
			free_one_page(zone, page, 0, migratetype);
			goto out;
		}
		migratetype = MIGRATE_MOVABLE;
	}

1394
	pcp = &this_cpu_ptr(zone->pageset)->pcp;
1395
	if (cold)
1396
		list_add_tail(&page->lru, &pcp->lists[migratetype]);
1397
	else
1398
		list_add(&page->lru, &pcp->lists[migratetype]);
L
Linus Torvalds 已提交
1399
	pcp->count++;
N
Nick Piggin 已提交
1400
	if (pcp->count >= pcp->high) {
1401 1402 1403
		unsigned long batch = ACCESS_ONCE(pcp->batch);
		free_pcppages_bulk(zone, batch, pcp);
		pcp->count -= batch;
N
Nick Piggin 已提交
1404
	}
1405 1406

out:
L
Linus Torvalds 已提交
1407 1408 1409
	local_irq_restore(flags);
}

1410 1411 1412 1413 1414 1415 1416 1417
/*
 * Free a list of 0-order pages
 */
void free_hot_cold_page_list(struct list_head *list, int cold)
{
	struct page *page, *next;

	list_for_each_entry_safe(page, next, list, lru) {
1418
		trace_mm_page_free_batched(page, cold);
1419 1420 1421 1422
		free_hot_cold_page(page, cold);
	}
}

N
Nick Piggin 已提交
1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434
/*
 * 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;

1435 1436
	VM_BUG_ON_PAGE(PageCompound(page), page);
	VM_BUG_ON_PAGE(!page_count(page), page);
1437 1438 1439 1440 1441 1442 1443 1444 1445 1446

#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

1447 1448
	for (i = 1; i < (1 << order); i++)
		set_page_refcounted(page + i);
N
Nick Piggin 已提交
1449
}
K
K. Y. Srinivasan 已提交
1450
EXPORT_SYMBOL_GPL(split_page);
N
Nick Piggin 已提交
1451

1452
static int __isolate_free_page(struct page *page, unsigned int order)
1453 1454 1455
{
	unsigned long watermark;
	struct zone *zone;
1456
	int mt;
1457 1458 1459 1460

	BUG_ON(!PageBuddy(page));

	zone = page_zone(page);
1461
	mt = get_pageblock_migratetype(page);
1462

1463
	if (!is_migrate_isolate(mt)) {
1464 1465 1466 1467 1468
		/* Obey watermarks as if the page was being allocated */
		watermark = low_wmark_pages(zone) + (1 << order);
		if (!zone_watermark_ok(zone, 0, watermark, 0, 0))
			return 0;

1469
		__mod_zone_freepage_state(zone, -(1UL << order), mt);
1470
	}
1471 1472 1473 1474 1475

	/* Remove page from free list */
	list_del(&page->lru);
	zone->free_area[order].nr_free--;
	rmv_page_order(page);
1476

1477
	/* Set the pageblock if the isolated page is at least a pageblock */
1478 1479
	if (order >= pageblock_order - 1) {
		struct page *endpage = page + (1 << order) - 1;
1480 1481
		for (; page < endpage; page += pageblock_nr_pages) {
			int mt = get_pageblock_migratetype(page);
1482
			if (!is_migrate_isolate(mt) && !is_migrate_cma(mt))
1483 1484 1485
				set_pageblock_migratetype(page,
							  MIGRATE_MOVABLE);
		}
1486 1487
	}

1488
	return 1UL << order;
1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507
}

/*
 * Similar to split_page except the page is already free. As this is only
 * being used for migration, the migratetype of the block also changes.
 * As this is called with interrupts disabled, the caller is responsible
 * for calling arch_alloc_page() and kernel_map_page() after interrupts
 * are enabled.
 *
 * Note: this is probably too low level an operation for use in drivers.
 * Please consult with lkml before using this in your driver.
 */
int split_free_page(struct page *page)
{
	unsigned int order;
	int nr_pages;

	order = page_order(page);

1508
	nr_pages = __isolate_free_page(page, order);
1509 1510 1511 1512 1513 1514 1515
	if (!nr_pages)
		return 0;

	/* Split into individual pages */
	set_page_refcounted(page);
	split_page(page, order);
	return nr_pages;
1516 1517
}

L
Linus Torvalds 已提交
1518 1519 1520 1521 1522
/*
 * Really, prep_compound_page() should be called from __rmqueue_bulk().  But
 * we cheat by calling it from here, in the order > 0 path.  Saves a branch
 * or two.
 */
1523 1524
static inline
struct page *buffered_rmqueue(struct zone *preferred_zone,
1525 1526
			struct zone *zone, int order, gfp_t gfp_flags,
			int migratetype)
L
Linus Torvalds 已提交
1527 1528
{
	unsigned long flags;
1529
	struct page *page;
L
Linus Torvalds 已提交
1530 1531
	int cold = !!(gfp_flags & __GFP_COLD);

1532
again:
N
Nick Piggin 已提交
1533
	if (likely(order == 0)) {
L
Linus Torvalds 已提交
1534
		struct per_cpu_pages *pcp;
1535
		struct list_head *list;
L
Linus Torvalds 已提交
1536 1537

		local_irq_save(flags);
1538 1539
		pcp = &this_cpu_ptr(zone->pageset)->pcp;
		list = &pcp->lists[migratetype];
1540
		if (list_empty(list)) {
1541
			pcp->count += rmqueue_bulk(zone, 0,
1542
					pcp->batch, list,
1543
					migratetype, cold);
1544
			if (unlikely(list_empty(list)))
1545
				goto failed;
1546
		}
1547

1548 1549 1550 1551 1552
		if (cold)
			page = list_entry(list->prev, struct page, lru);
		else
			page = list_entry(list->next, struct page, lru);

1553 1554
		list_del(&page->lru);
		pcp->count--;
R
Rohit Seth 已提交
1555
	} else {
1556 1557 1558 1559 1560 1561 1562 1563
		if (unlikely(gfp_flags & __GFP_NOFAIL)) {
			/*
			 * __GFP_NOFAIL is not to be used in new code.
			 *
			 * All __GFP_NOFAIL callers should be fixed so that they
			 * properly detect and handle allocation failures.
			 *
			 * We most definitely don't want callers attempting to
1564
			 * allocate greater than order-1 page units with
1565 1566
			 * __GFP_NOFAIL.
			 */
1567
			WARN_ON_ONCE(order > 1);
1568
		}
L
Linus Torvalds 已提交
1569
		spin_lock_irqsave(&zone->lock, flags);
1570
		page = __rmqueue(zone, order, migratetype);
N
Nick Piggin 已提交
1571 1572 1573
		spin_unlock(&zone->lock);
		if (!page)
			goto failed;
1574 1575
		__mod_zone_freepage_state(zone, -(1 << order),
					  get_pageblock_migratetype(page));
L
Linus Torvalds 已提交
1576 1577
	}

1578
	__mod_zone_page_state(zone, NR_ALLOC_BATCH, -(1 << order));
1579

1580
	__count_zone_vm_events(PGALLOC, zone, 1 << order);
A
Andi Kleen 已提交
1581
	zone_statistics(preferred_zone, zone, gfp_flags);
N
Nick Piggin 已提交
1582
	local_irq_restore(flags);
L
Linus Torvalds 已提交
1583

1584
	VM_BUG_ON_PAGE(bad_range(zone, page), page);
N
Nick Piggin 已提交
1585
	if (prep_new_page(page, order, gfp_flags))
N
Nick Piggin 已提交
1586
		goto again;
L
Linus Torvalds 已提交
1587
	return page;
N
Nick Piggin 已提交
1588 1589 1590 1591

failed:
	local_irq_restore(flags);
	return NULL;
L
Linus Torvalds 已提交
1592 1593
}

1594 1595
#ifdef CONFIG_FAIL_PAGE_ALLOC

1596
static struct {
1597 1598 1599 1600
	struct fault_attr attr;

	u32 ignore_gfp_highmem;
	u32 ignore_gfp_wait;
1601
	u32 min_order;
1602 1603
} fail_page_alloc = {
	.attr = FAULT_ATTR_INITIALIZER,
1604 1605
	.ignore_gfp_wait = 1,
	.ignore_gfp_highmem = 1,
1606
	.min_order = 1,
1607 1608 1609 1610 1611 1612 1613 1614
};

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);

1615
static bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
1616
{
1617
	if (order < fail_page_alloc.min_order)
1618
		return false;
1619
	if (gfp_mask & __GFP_NOFAIL)
1620
		return false;
1621
	if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM))
1622
		return false;
1623
	if (fail_page_alloc.ignore_gfp_wait && (gfp_mask & __GFP_WAIT))
1624
		return false;
1625 1626 1627 1628 1629 1630 1631 1632

	return should_fail(&fail_page_alloc.attr, 1 << order);
}

#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS

static int __init fail_page_alloc_debugfs(void)
{
A
Al Viro 已提交
1633
	umode_t mode = S_IFREG | S_IRUSR | S_IWUSR;
1634 1635
	struct dentry *dir;

1636 1637 1638 1639
	dir = fault_create_debugfs_attr("fail_page_alloc", NULL,
					&fail_page_alloc.attr);
	if (IS_ERR(dir))
		return PTR_ERR(dir);
1640

1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652
	if (!debugfs_create_bool("ignore-gfp-wait", mode, dir,
				&fail_page_alloc.ignore_gfp_wait))
		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:
1653
	debugfs_remove_recursive(dir);
1654

1655
	return -ENOMEM;
1656 1657 1658 1659 1660 1661 1662 1663
}

late_initcall(fail_page_alloc_debugfs);

#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */

#else /* CONFIG_FAIL_PAGE_ALLOC */

1664
static inline bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
1665
{
1666
	return false;
1667 1668 1669 1670
}

#endif /* CONFIG_FAIL_PAGE_ALLOC */

L
Linus Torvalds 已提交
1671
/*
1672
 * Return true if free pages are above 'mark'. This takes into account the order
L
Linus Torvalds 已提交
1673 1674
 * of the allocation.
 */
1675 1676
static bool __zone_watermark_ok(struct zone *z, int order, unsigned long mark,
		      int classzone_idx, int alloc_flags, long free_pages)
L
Linus Torvalds 已提交
1677 1678
{
	/* free_pages my go negative - that's OK */
1679
	long min = mark;
1680
	long lowmem_reserve = z->lowmem_reserve[classzone_idx];
L
Linus Torvalds 已提交
1681
	int o;
1682
	long free_cma = 0;
L
Linus Torvalds 已提交
1683

1684
	free_pages -= (1 << order) - 1;
R
Rohit Seth 已提交
1685
	if (alloc_flags & ALLOC_HIGH)
L
Linus Torvalds 已提交
1686
		min -= min / 2;
R
Rohit Seth 已提交
1687
	if (alloc_flags & ALLOC_HARDER)
L
Linus Torvalds 已提交
1688
		min -= min / 4;
1689 1690 1691
#ifdef CONFIG_CMA
	/* If allocation can't use CMA areas don't use free CMA pages */
	if (!(alloc_flags & ALLOC_CMA))
1692
		free_cma = zone_page_state(z, NR_FREE_CMA_PAGES);
1693
#endif
1694 1695

	if (free_pages - free_cma <= min + lowmem_reserve)
1696
		return false;
L
Linus Torvalds 已提交
1697 1698 1699 1700 1701 1702 1703 1704
	for (o = 0; o < order; o++) {
		/* At the next order, this order's pages become unavailable */
		free_pages -= z->free_area[o].nr_free << o;

		/* Require fewer higher order pages to be free */
		min >>= 1;

		if (free_pages <= min)
1705
			return false;
L
Linus Torvalds 已提交
1706
	}
1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726
	return true;
}

bool zone_watermark_ok(struct zone *z, int order, unsigned long mark,
		      int classzone_idx, int alloc_flags)
{
	return __zone_watermark_ok(z, order, mark, classzone_idx, alloc_flags,
					zone_page_state(z, NR_FREE_PAGES));
}

bool zone_watermark_ok_safe(struct zone *z, int order, unsigned long mark,
		      int classzone_idx, int alloc_flags)
{
	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, alloc_flags,
								free_pages);
L
Linus Torvalds 已提交
1727 1728
}

1729 1730 1731 1732 1733 1734
#ifdef CONFIG_NUMA
/*
 * zlc_setup - Setup for "zonelist cache".  Uses cached zone data to
 * skip over zones that are not allowed by the cpuset, or that have
 * been recently (in last second) found to be nearly full.  See further
 * comments in mmzone.h.  Reduces cache footprint of zonelist scans
S
Simon Arlott 已提交
1735
 * that have to skip over a lot of full or unallowed zones.
1736
 *
1737
 * If the zonelist cache is present in the passed zonelist, then
1738
 * returns a pointer to the allowed node mask (either the current
1739
 * tasks mems_allowed, or node_states[N_MEMORY].)
1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760
 *
 * If the zonelist cache is not available for this zonelist, does
 * nothing and returns NULL.
 *
 * If the fullzones BITMAP in the zonelist cache is stale (more than
 * a second since last zap'd) then we zap it out (clear its bits.)
 *
 * We hold off even calling zlc_setup, until after we've checked the
 * first zone in the zonelist, on the theory that most allocations will
 * be satisfied from that first zone, so best to examine that zone as
 * quickly as we can.
 */
static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags)
{
	struct zonelist_cache *zlc;	/* cached zonelist speedup info */
	nodemask_t *allowednodes;	/* zonelist_cache approximation */

	zlc = zonelist->zlcache_ptr;
	if (!zlc)
		return NULL;

S
S.Caglar Onur 已提交
1761
	if (time_after(jiffies, zlc->last_full_zap + HZ)) {
1762 1763 1764 1765 1766 1767
		bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
		zlc->last_full_zap = jiffies;
	}

	allowednodes = !in_interrupt() && (alloc_flags & ALLOC_CPUSET) ?
					&cpuset_current_mems_allowed :
1768
					&node_states[N_MEMORY];
1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793
	return allowednodes;
}

/*
 * Given 'z' scanning a zonelist, run a couple of quick checks to see
 * if it is worth looking at further for free memory:
 *  1) Check that the zone isn't thought to be full (doesn't have its
 *     bit set in the zonelist_cache fullzones BITMAP).
 *  2) Check that the zones node (obtained from the zonelist_cache
 *     z_to_n[] mapping) is allowed in the passed in allowednodes mask.
 * Return true (non-zero) if zone is worth looking at further, or
 * else return false (zero) if it is not.
 *
 * This check -ignores- the distinction between various watermarks,
 * such as GFP_HIGH, GFP_ATOMIC, PF_MEMALLOC, ...  If a zone is
 * found to be full for any variation of these watermarks, it will
 * be considered full for up to one second by all requests, unless
 * we are so low on memory on all allowed nodes that we are forced
 * into the second scan of the zonelist.
 *
 * In the second scan we ignore this zonelist cache and exactly
 * apply the watermarks to all zones, even it is slower to do so.
 * We are low on memory in the second scan, and should leave no stone
 * unturned looking for a free page.
 */
1794
static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z,
1795 1796 1797 1798 1799 1800 1801 1802 1803 1804
						nodemask_t *allowednodes)
{
	struct zonelist_cache *zlc;	/* cached zonelist speedup info */
	int i;				/* index of *z in zonelist zones */
	int n;				/* node that zone *z is on */

	zlc = zonelist->zlcache_ptr;
	if (!zlc)
		return 1;

1805
	i = z - zonelist->_zonerefs;
1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816
	n = zlc->z_to_n[i];

	/* This zone is worth trying if it is allowed but not full */
	return node_isset(n, *allowednodes) && !test_bit(i, zlc->fullzones);
}

/*
 * Given 'z' scanning a zonelist, set the corresponding bit in
 * zlc->fullzones, so that subsequent attempts to allocate a page
 * from that zone don't waste time re-examining it.
 */
1817
static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z)
1818 1819 1820 1821 1822 1823 1824 1825
{
	struct zonelist_cache *zlc;	/* cached zonelist speedup info */
	int i;				/* index of *z in zonelist zones */

	zlc = zonelist->zlcache_ptr;
	if (!zlc)
		return;

1826
	i = z - zonelist->_zonerefs;
1827 1828 1829 1830

	set_bit(i, zlc->fullzones);
}

1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845
/*
 * clear all zones full, called after direct reclaim makes progress so that
 * a zone that was recently full is not skipped over for up to a second
 */
static void zlc_clear_zones_full(struct zonelist *zonelist)
{
	struct zonelist_cache *zlc;	/* cached zonelist speedup info */

	zlc = zonelist->zlcache_ptr;
	if (!zlc)
		return;

	bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
}

1846 1847
static bool zone_local(struct zone *local_zone, struct zone *zone)
{
1848
	return local_zone->node == zone->node;
1849 1850
}

1851 1852 1853 1854 1855 1856 1857 1858 1859
static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone)
{
	return node_isset(local_zone->node, zone->zone_pgdat->reclaim_nodes);
}

static void __paginginit init_zone_allows_reclaim(int nid)
{
	int i;

1860
	for_each_node_state(i, N_MEMORY)
1861
		if (node_distance(nid, i) <= RECLAIM_DISTANCE)
1862
			node_set(i, NODE_DATA(nid)->reclaim_nodes);
1863
		else
1864 1865 1866
			zone_reclaim_mode = 1;
}

1867 1868 1869 1870 1871 1872 1873
#else	/* CONFIG_NUMA */

static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags)
{
	return NULL;
}

1874
static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z,
1875 1876 1877 1878 1879
				nodemask_t *allowednodes)
{
	return 1;
}

1880
static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z)
1881 1882
{
}
1883 1884 1885 1886

static void zlc_clear_zones_full(struct zonelist *zonelist)
{
}
1887

1888 1889 1890 1891 1892
static bool zone_local(struct zone *local_zone, struct zone *zone)
{
	return true;
}

1893 1894 1895 1896 1897 1898 1899 1900
static bool zone_allows_reclaim(struct zone *local_zone, struct zone *zone)
{
	return true;
}

static inline void init_zone_allows_reclaim(int nid)
{
}
1901 1902
#endif	/* CONFIG_NUMA */

R
Rohit Seth 已提交
1903
/*
1904
 * get_page_from_freelist goes through the zonelist trying to allocate
R
Rohit Seth 已提交
1905 1906 1907
 * a page.
 */
static struct page *
1908
get_page_from_freelist(gfp_t gfp_mask, nodemask_t *nodemask, unsigned int order,
1909
		struct zonelist *zonelist, int high_zoneidx, int alloc_flags,
1910
		struct zone *preferred_zone, int migratetype)
M
Martin Hicks 已提交
1911
{
1912
	struct zoneref *z;
R
Rohit Seth 已提交
1913
	struct page *page = NULL;
1914
	int classzone_idx;
1915
	struct zone *zone;
1916 1917 1918
	nodemask_t *allowednodes = NULL;/* zonelist_cache approximation */
	int zlc_active = 0;		/* set if using zonelist_cache */
	int did_zlc_setup = 0;		/* just call zlc_setup() one time */
1919

1920
	classzone_idx = zone_idx(preferred_zone);
1921
zonelist_scan:
R
Rohit Seth 已提交
1922
	/*
1923
	 * Scan zonelist, looking for a zone with enough free.
1924
	 * See also __cpuset_node_allowed_softwall() comment in kernel/cpuset.c.
R
Rohit Seth 已提交
1925
	 */
1926 1927
	for_each_zone_zonelist_nodemask(zone, z, zonelist,
						high_zoneidx, nodemask) {
1928 1929
		unsigned long mark;

1930
		if (IS_ENABLED(CONFIG_NUMA) && zlc_active &&
1931 1932
			!zlc_zone_worth_trying(zonelist, z, allowednodes))
				continue;
R
Rohit Seth 已提交
1933
		if ((alloc_flags & ALLOC_CPUSET) &&
1934
			!cpuset_zone_allowed_softwall(zone, gfp_mask))
1935
				continue;
1936
		BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK);
1937
		if (unlikely(alloc_flags & ALLOC_NO_WATERMARKS))
1938
			goto try_this_zone;
1939 1940 1941 1942 1943 1944
		/*
		 * Distribute pages in proportion to the individual
		 * zone size to ensure fair page aging.  The zone a
		 * page was allocated in should have no effect on the
		 * time the page has in memory before being reclaimed.
		 */
1945
		if (alloc_flags & ALLOC_FAIR) {
1946
			if (!zone_local(preferred_zone, zone))
1947
				continue;
1948 1949
			if (zone_page_state(zone, NR_ALLOC_BATCH) <= 0)
				continue;
1950
		}
1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979
		/*
		 * When allocating a page cache page for writing, we
		 * want to get it from a zone that is within its dirty
		 * limit, such that no single zone holds more than its
		 * proportional share of globally allowed dirty pages.
		 * The dirty limits take into account the zone's
		 * lowmem reserves and high watermark so that kswapd
		 * should be able to balance it without having to
		 * write pages from its LRU list.
		 *
		 * This may look like it could increase pressure on
		 * lower zones by failing allocations in higher zones
		 * before they are full.  But the pages that do spill
		 * over are limited as the lower zones are protected
		 * by this very same mechanism.  It should not become
		 * a practical burden to them.
		 *
		 * XXX: For now, allow allocations to potentially
		 * exceed the per-zone dirty limit in the slowpath
		 * (ALLOC_WMARK_LOW unset) before going into reclaim,
		 * which is important when on a NUMA setup the allowed
		 * zones are together not big enough to reach the
		 * global limit.  The proper fix for these situations
		 * will require awareness of zones in the
		 * dirty-throttling and the flusher threads.
		 */
		if ((alloc_flags & ALLOC_WMARK_LOW) &&
		    (gfp_mask & __GFP_WRITE) && !zone_dirty_ok(zone))
			goto this_zone_full;
R
Rohit Seth 已提交
1980

1981 1982 1983
		mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK];
		if (!zone_watermark_ok(zone, order, mark,
				       classzone_idx, alloc_flags)) {
1984 1985
			int ret;

1986 1987
			if (IS_ENABLED(CONFIG_NUMA) &&
					!did_zlc_setup && nr_online_nodes > 1) {
1988 1989 1990 1991 1992 1993 1994 1995 1996 1997
				/*
				 * we do zlc_setup if there are multiple nodes
				 * and before considering the first zone allowed
				 * by the cpuset.
				 */
				allowednodes = zlc_setup(zonelist, alloc_flags);
				zlc_active = 1;
				did_zlc_setup = 1;
			}

1998 1999
			if (zone_reclaim_mode == 0 ||
			    !zone_allows_reclaim(preferred_zone, zone))
2000 2001
				goto this_zone_full;

2002 2003 2004 2005
			/*
			 * As we may have just activated ZLC, check if the first
			 * eligible zone has failed zone_reclaim recently.
			 */
2006
			if (IS_ENABLED(CONFIG_NUMA) && zlc_active &&
2007 2008 2009
				!zlc_zone_worth_trying(zonelist, z, allowednodes))
				continue;

2010 2011 2012 2013
			ret = zone_reclaim(zone, gfp_mask, order);
			switch (ret) {
			case ZONE_RECLAIM_NOSCAN:
				/* did not scan */
2014
				continue;
2015 2016
			case ZONE_RECLAIM_FULL:
				/* scanned but unreclaimable */
2017
				continue;
2018 2019
			default:
				/* did we reclaim enough */
2020
				if (zone_watermark_ok(zone, order, mark,
2021
						classzone_idx, alloc_flags))
2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034
					goto try_this_zone;

				/*
				 * Failed to reclaim enough to meet watermark.
				 * Only mark the zone full if checking the min
				 * watermark or if we failed to reclaim just
				 * 1<<order pages or else the page allocator
				 * fastpath will prematurely mark zones full
				 * when the watermark is between the low and
				 * min watermarks.
				 */
				if (((alloc_flags & ALLOC_WMARK_MASK) == ALLOC_WMARK_MIN) ||
				    ret == ZONE_RECLAIM_SOME)
2035
					goto this_zone_full;
2036 2037

				continue;
2038
			}
R
Rohit Seth 已提交
2039 2040
		}

2041
try_this_zone:
2042 2043
		page = buffered_rmqueue(preferred_zone, zone, order,
						gfp_mask, migratetype);
2044
		if (page)
R
Rohit Seth 已提交
2045
			break;
2046
this_zone_full:
2047
		if (IS_ENABLED(CONFIG_NUMA))
2048
			zlc_mark_zone_full(zonelist, z);
2049
	}
2050

2051
	if (unlikely(IS_ENABLED(CONFIG_NUMA) && page == NULL && zlc_active)) {
2052 2053 2054 2055
		/* Disable zlc cache for second zonelist scan */
		zlc_active = 0;
		goto zonelist_scan;
	}
2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066

	if (page)
		/*
		 * page->pfmemalloc is set 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.
		 */
		page->pfmemalloc = !!(alloc_flags & ALLOC_NO_WATERMARKS);

R
Rohit Seth 已提交
2067
	return page;
M
Martin Hicks 已提交
2068 2069
}

2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083
/*
 * 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;
}

2084 2085 2086 2087 2088 2089 2090 2091
static DEFINE_RATELIMIT_STATE(nopage_rs,
		DEFAULT_RATELIMIT_INTERVAL,
		DEFAULT_RATELIMIT_BURST);

void warn_alloc_failed(gfp_t gfp_mask, int order, const char *fmt, ...)
{
	unsigned int filter = SHOW_MEM_FILTER_NODES;

2092 2093
	if ((gfp_mask & __GFP_NOWARN) || !__ratelimit(&nopage_rs) ||
	    debug_guardpage_minorder() > 0)
2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108
		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_WAIT))
		filter &= ~SHOW_MEM_FILTER_NODES;

	if (fmt) {
J
Joe Perches 已提交
2109 2110 2111
		struct va_format vaf;
		va_list args;

2112
		va_start(args, fmt);
J
Joe Perches 已提交
2113 2114 2115 2116 2117 2118

		vaf.fmt = fmt;
		vaf.va = &args;

		pr_warn("%pV", &vaf);

2119 2120 2121
		va_end(args);
	}

J
Joe Perches 已提交
2122 2123
	pr_warn("%s: page allocation failure: order:%d, mode:0x%x\n",
		current->comm, order, gfp_mask);
2124 2125 2126 2127 2128 2129

	dump_stack();
	if (!should_suppress_show_mem())
		show_mem(filter);
}

2130 2131
static inline int
should_alloc_retry(gfp_t gfp_mask, unsigned int order,
2132
				unsigned long did_some_progress,
2133
				unsigned long pages_reclaimed)
L
Linus Torvalds 已提交
2134
{
2135 2136 2137
	/* Do not loop if specifically requested */
	if (gfp_mask & __GFP_NORETRY)
		return 0;
L
Linus Torvalds 已提交
2138

2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150
	/* Always retry if specifically requested */
	if (gfp_mask & __GFP_NOFAIL)
		return 1;

	/*
	 * Suspend converts GFP_KERNEL to __GFP_WAIT which can prevent reclaim
	 * making forward progress without invoking OOM. Suspend also disables
	 * storage devices so kswapd will not help. Bail if we are suspending.
	 */
	if (!did_some_progress && pm_suspended_storage())
		return 0;

2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167
	/*
	 * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER
	 * means __GFP_NOFAIL, but that may not be true in other
	 * implementations.
	 */
	if (order <= PAGE_ALLOC_COSTLY_ORDER)
		return 1;

	/*
	 * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is
	 * specified, then we retry until we no longer reclaim any pages
	 * (above), or we've reclaimed an order of pages at least as
	 * large as the allocation's order. In both cases, if the
	 * allocation still fails, we stop retrying.
	 */
	if (gfp_mask & __GFP_REPEAT && pages_reclaimed < (1 << order))
		return 1;
2168

2169 2170
	return 0;
}
2171

2172 2173 2174
static inline struct page *
__alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
	struct zonelist *zonelist, enum zone_type high_zoneidx,
2175 2176
	nodemask_t *nodemask, struct zone *preferred_zone,
	int migratetype)
2177 2178 2179 2180
{
	struct page *page;

	/* Acquire the OOM killer lock for the zones in zonelist */
2181
	if (!try_set_zonelist_oom(zonelist, gfp_mask)) {
2182
		schedule_timeout_uninterruptible(1);
L
Linus Torvalds 已提交
2183 2184
		return NULL;
	}
2185

2186 2187 2188 2189 2190 2191 2192
	/*
	 * 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, nodemask,
		order, zonelist, high_zoneidx,
2193
		ALLOC_WMARK_HIGH|ALLOC_CPUSET,
2194
		preferred_zone, migratetype);
R
Rohit Seth 已提交
2195
	if (page)
2196 2197
		goto out;

2198 2199 2200 2201
	if (!(gfp_mask & __GFP_NOFAIL)) {
		/* The OOM killer will not help higher order allocs */
		if (order > PAGE_ALLOC_COSTLY_ORDER)
			goto out;
2202 2203 2204
		/* The OOM killer does not needlessly kill tasks for lowmem */
		if (high_zoneidx < ZONE_NORMAL)
			goto out;
2205 2206 2207 2208 2209 2210 2211 2212 2213 2214
		/*
		 * GFP_THISNODE contains __GFP_NORETRY and we never hit this.
		 * Sanity check for bare calls of __GFP_THISNODE, not real OOM.
		 * The caller should handle page allocation failure by itself if
		 * it specifies __GFP_THISNODE.
		 * Note: Hugepage uses it but will hit PAGE_ALLOC_COSTLY_ORDER.
		 */
		if (gfp_mask & __GFP_THISNODE)
			goto out;
	}
2215
	/* Exhausted what can be done so it's blamo time */
2216
	out_of_memory(zonelist, gfp_mask, order, nodemask, false);
2217 2218 2219 2220 2221 2222

out:
	clear_zonelist_oom(zonelist, gfp_mask);
	return page;
}

2223 2224 2225 2226 2227 2228
#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,
	struct zonelist *zonelist, enum zone_type high_zoneidx,
	nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
2229
	int migratetype, bool sync_migration,
2230
	bool *contended_compaction, bool *deferred_compaction,
2231
	unsigned long *did_some_progress)
2232
{
2233
	if (!order)
2234 2235
		return NULL;

2236
	if (compaction_deferred(preferred_zone, order)) {
2237 2238 2239 2240
		*deferred_compaction = true;
		return NULL;
	}

2241
	current->flags |= PF_MEMALLOC;
2242
	*did_some_progress = try_to_compact_pages(zonelist, order, gfp_mask,
2243
						nodemask, sync_migration,
2244
						contended_compaction);
2245
	current->flags &= ~PF_MEMALLOC;
2246

2247
	if (*did_some_progress != COMPACT_SKIPPED) {
2248 2249
		struct page *page;

2250 2251 2252 2253 2254 2255
		/* Page migration frees to the PCP lists but we want merging */
		drain_pages(get_cpu());
		put_cpu();

		page = get_page_from_freelist(gfp_mask, nodemask,
				order, zonelist, high_zoneidx,
2256 2257
				alloc_flags & ~ALLOC_NO_WATERMARKS,
				preferred_zone, migratetype);
2258
		if (page) {
2259
			preferred_zone->compact_blockskip_flush = false;
2260
			compaction_defer_reset(preferred_zone, order, true);
2261 2262 2263 2264 2265 2266 2267 2268 2269 2270
			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);
2271 2272 2273 2274 2275 2276

		/*
		 * As async compaction considers a subset of pageblocks, only
		 * defer if the failure was a sync compaction failure.
		 */
		if (sync_migration)
2277
			defer_compaction(preferred_zone, order);
2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288

		cond_resched();
	}

	return NULL;
}
#else
static inline struct page *
__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
	struct zonelist *zonelist, enum zone_type high_zoneidx,
	nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
2289
	int migratetype, bool sync_migration,
2290
	bool *contended_compaction, bool *deferred_compaction,
2291
	unsigned long *did_some_progress)
2292 2293 2294 2295 2296
{
	return NULL;
}
#endif /* CONFIG_COMPACTION */

2297 2298 2299 2300
/* Perform direct synchronous page reclaim */
static int
__perform_reclaim(gfp_t gfp_mask, unsigned int order, struct zonelist *zonelist,
		  nodemask_t *nodemask)
2301 2302
{
	struct reclaim_state reclaim_state;
2303
	int progress;
2304 2305 2306 2307 2308

	cond_resched();

	/* We now go into synchronous reclaim */
	cpuset_memory_pressure_bump();
2309
	current->flags |= PF_MEMALLOC;
2310 2311
	lockdep_set_current_reclaim_state(gfp_mask);
	reclaim_state.reclaimed_slab = 0;
2312
	current->reclaim_state = &reclaim_state;
2313

2314
	progress = try_to_free_pages(zonelist, order, gfp_mask, nodemask);
2315

2316
	current->reclaim_state = NULL;
2317
	lockdep_clear_current_reclaim_state();
2318
	current->flags &= ~PF_MEMALLOC;
2319 2320 2321

	cond_resched();

2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336
	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,
	struct zonelist *zonelist, enum zone_type high_zoneidx,
	nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
	int migratetype, unsigned long *did_some_progress)
{
	struct page *page = NULL;
	bool drained = false;

	*did_some_progress = __perform_reclaim(gfp_mask, order, zonelist,
					       nodemask);
2337 2338
	if (unlikely(!(*did_some_progress)))
		return NULL;
2339

2340
	/* After successful reclaim, reconsider all zones for allocation */
2341
	if (IS_ENABLED(CONFIG_NUMA))
2342 2343
		zlc_clear_zones_full(zonelist);

2344 2345
retry:
	page = get_page_from_freelist(gfp_mask, nodemask, order,
2346
					zonelist, high_zoneidx,
2347 2348
					alloc_flags & ~ALLOC_NO_WATERMARKS,
					preferred_zone, migratetype);
2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359

	/*
	 * If an allocation failed after direct reclaim, it could be because
	 * pages are pinned on the per-cpu lists. Drain them and try again
	 */
	if (!page && !drained) {
		drain_all_pages();
		drained = true;
		goto retry;
	}

2360 2361 2362
	return page;
}

L
Linus Torvalds 已提交
2363
/*
2364 2365
 * This is called in the allocator slow-path if the allocation request is of
 * sufficient urgency to ignore watermarks and take other desperate measures
L
Linus Torvalds 已提交
2366
 */
2367 2368 2369
static inline struct page *
__alloc_pages_high_priority(gfp_t gfp_mask, unsigned int order,
	struct zonelist *zonelist, enum zone_type high_zoneidx,
2370 2371
	nodemask_t *nodemask, struct zone *preferred_zone,
	int migratetype)
2372 2373 2374 2375 2376
{
	struct page *page;

	do {
		page = get_page_from_freelist(gfp_mask, nodemask, order,
2377
			zonelist, high_zoneidx, ALLOC_NO_WATERMARKS,
2378
			preferred_zone, migratetype);
2379 2380

		if (!page && gfp_mask & __GFP_NOFAIL)
2381
			wait_iff_congested(preferred_zone, BLK_RW_ASYNC, HZ/50);
2382 2383 2384 2385 2386
	} while (!page && (gfp_mask & __GFP_NOFAIL));

	return page;
}

2387 2388 2389
static void reset_alloc_batches(struct zonelist *zonelist,
				enum zone_type high_zoneidx,
				struct zone *preferred_zone)
L
Linus Torvalds 已提交
2390
{
2391 2392
	struct zoneref *z;
	struct zone *zone;
L
Linus Torvalds 已提交
2393

2394 2395 2396
	for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
		/*
		 * Only reset the batches of zones that were actually
2397 2398
		 * considered in the fairness pass, we don't want to
		 * trash fairness information for zones that are not
2399 2400
		 * actually part of this zonelist's round-robin cycle.
		 */
2401
		if (!zone_local(preferred_zone, zone))
2402 2403
			continue;
		mod_zone_page_state(zone, NR_ALLOC_BATCH,
2404 2405
			high_wmark_pages(zone) - low_wmark_pages(zone) -
			atomic_long_read(&zone->vm_stat[NR_ALLOC_BATCH]));
2406
	}
2407
}
2408

2409 2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420
static void wake_all_kswapds(unsigned int order,
			     struct zonelist *zonelist,
			     enum zone_type high_zoneidx,
			     struct zone *preferred_zone)
{
	struct zoneref *z;
	struct zone *zone;

	for_each_zone_zonelist(zone, z, zonelist, high_zoneidx)
		wakeup_kswapd(zone, order, zone_idx(preferred_zone));
}

2421 2422 2423 2424 2425
static inline int
gfp_to_alloc_flags(gfp_t gfp_mask)
{
	int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET;
	const gfp_t wait = gfp_mask & __GFP_WAIT;
L
Linus Torvalds 已提交
2426

2427
	/* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
2428
	BUILD_BUG_ON(__GFP_HIGH != (__force gfp_t) ALLOC_HIGH);
2429

2430 2431 2432 2433 2434 2435
	/*
	 * 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 (!wait) and ALLOC_HIGH (__GFP_HIGH).
	 */
2436
	alloc_flags |= (__force int) (gfp_mask & __GFP_HIGH);
L
Linus Torvalds 已提交
2437

2438
	if (!wait) {
2439 2440 2441 2442 2443 2444
		/*
		 * Not worth trying to allocate harder for
		 * __GFP_NOMEMALLOC even if it can't schedule.
		 */
		if  (!(gfp_mask & __GFP_NOMEMALLOC))
			alloc_flags |= ALLOC_HARDER;
2445
		/*
2446 2447
		 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
		 * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
2448
		 */
2449
		alloc_flags &= ~ALLOC_CPUSET;
2450
	} else if (unlikely(rt_task(current)) && !in_interrupt())
2451 2452
		alloc_flags |= ALLOC_HARDER;

2453 2454 2455
	if (likely(!(gfp_mask & __GFP_NOMEMALLOC))) {
		if (gfp_mask & __GFP_MEMALLOC)
			alloc_flags |= ALLOC_NO_WATERMARKS;
2456 2457 2458 2459 2460
		else if (in_serving_softirq() && (current->flags & PF_MEMALLOC))
			alloc_flags |= ALLOC_NO_WATERMARKS;
		else if (!in_interrupt() &&
				((current->flags & PF_MEMALLOC) ||
				 unlikely(test_thread_flag(TIF_MEMDIE))))
2461
			alloc_flags |= ALLOC_NO_WATERMARKS;
L
Linus Torvalds 已提交
2462
	}
2463 2464 2465 2466
#ifdef CONFIG_CMA
	if (allocflags_to_migratetype(gfp_mask) == MIGRATE_MOVABLE)
		alloc_flags |= ALLOC_CMA;
#endif
2467 2468 2469
	return alloc_flags;
}

2470 2471
bool gfp_pfmemalloc_allowed(gfp_t gfp_mask)
{
2472
	return !!(gfp_to_alloc_flags(gfp_mask) & ALLOC_NO_WATERMARKS);
2473 2474
}

2475 2476 2477
static inline struct page *
__alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
	struct zonelist *zonelist, enum zone_type high_zoneidx,
2478 2479
	nodemask_t *nodemask, struct zone *preferred_zone,
	int migratetype)
2480 2481 2482 2483 2484 2485
{
	const gfp_t wait = gfp_mask & __GFP_WAIT;
	struct page *page = NULL;
	int alloc_flags;
	unsigned long pages_reclaimed = 0;
	unsigned long did_some_progress;
2486
	bool sync_migration = false;
2487
	bool deferred_compaction = false;
2488
	bool contended_compaction = false;
L
Linus Torvalds 已提交
2489

2490 2491 2492 2493 2494 2495
	/*
	 * 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.
	 */
2496 2497
	if (order >= MAX_ORDER) {
		WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN));
2498
		return NULL;
2499
	}
L
Linus Torvalds 已提交
2500

2501 2502 2503 2504 2505 2506 2507 2508
	/*
	 * GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and
	 * __GFP_NOWARN set) should not cause reclaim since the subsystem
	 * (f.e. slab) using GFP_THISNODE may choose to trigger reclaim
	 * using a larger set of nodes after it has established that the
	 * allowed per node queues are empty and that nodes are
	 * over allocated.
	 */
2509 2510
	if (IS_ENABLED(CONFIG_NUMA) &&
	    (gfp_mask & GFP_THISNODE) == GFP_THISNODE)
2511 2512
		goto nopage;

2513
restart:
2514 2515
	if (!(gfp_mask & __GFP_NO_KSWAPD))
		wake_all_kswapds(order, zonelist, high_zoneidx, preferred_zone);
L
Linus Torvalds 已提交
2516

2517
	/*
R
Rohit Seth 已提交
2518 2519 2520
	 * OK, we're below the kswapd watermark and have kicked background
	 * reclaim. Now things get more complex, so set up alloc_flags according
	 * to how we want to proceed.
2521
	 */
2522
	alloc_flags = gfp_to_alloc_flags(gfp_mask);
L
Linus Torvalds 已提交
2523

2524 2525 2526 2527 2528 2529 2530 2531
	/*
	 * Find the true preferred zone if the allocation is unconstrained by
	 * cpusets.
	 */
	if (!(alloc_flags & ALLOC_CPUSET) && !nodemask)
		first_zones_zonelist(zonelist, high_zoneidx, NULL,
					&preferred_zone);

2532
rebalance:
2533
	/* This is the last chance, in general, before the goto nopage. */
2534
	page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist,
2535 2536
			high_zoneidx, alloc_flags & ~ALLOC_NO_WATERMARKS,
			preferred_zone, migratetype);
R
Rohit Seth 已提交
2537 2538
	if (page)
		goto got_pg;
L
Linus Torvalds 已提交
2539

2540
	/* Allocate without watermarks if the context allows */
2541
	if (alloc_flags & ALLOC_NO_WATERMARKS) {
2542 2543 2544 2545 2546 2547 2548
		/*
		 * Ignore mempolicies if ALLOC_NO_WATERMARKS on the grounds
		 * the allocation is high priority and these type of
		 * allocations are system rather than user orientated
		 */
		zonelist = node_zonelist(numa_node_id(), gfp_mask);

2549 2550 2551
		page = __alloc_pages_high_priority(gfp_mask, order,
				zonelist, high_zoneidx, nodemask,
				preferred_zone, migratetype);
2552
		if (page) {
2553
			goto got_pg;
2554
		}
L
Linus Torvalds 已提交
2555 2556 2557
	}

	/* Atomic allocations - we can't balance anything */
2558 2559 2560 2561 2562 2563 2564
	if (!wait) {
		/*
		 * All existing users of the deprecated __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);
L
Linus Torvalds 已提交
2565
		goto nopage;
2566
	}
L
Linus Torvalds 已提交
2567

2568
	/* Avoid recursion of direct reclaim */
2569
	if (current->flags & PF_MEMALLOC)
2570 2571
		goto nopage;

2572 2573 2574 2575
	/* Avoid allocations with no watermarks from looping endlessly */
	if (test_thread_flag(TIF_MEMDIE) && !(gfp_mask & __GFP_NOFAIL))
		goto nopage;

2576 2577 2578 2579
	/*
	 * Try direct compaction. The first pass is asynchronous. Subsequent
	 * attempts after direct reclaim are synchronous
	 */
2580 2581 2582 2583
	page = __alloc_pages_direct_compact(gfp_mask, order,
					zonelist, high_zoneidx,
					nodemask,
					alloc_flags, preferred_zone,
2584
					migratetype, sync_migration,
2585
					&contended_compaction,
2586 2587
					&deferred_compaction,
					&did_some_progress);
2588 2589
	if (page)
		goto got_pg;
2590
	sync_migration = true;
2591

2592 2593 2594 2595 2596 2597 2598
	/*
	 * If compaction is deferred for high-order allocations, it is because
	 * sync compaction recently failed. In this is the case and the caller
	 * requested a movable allocation that does not heavily disrupt the
	 * system then fail the allocation instead of entering direct reclaim.
	 */
	if ((deferred_compaction || contended_compaction) &&
2599
						(gfp_mask & __GFP_NO_KSWAPD))
2600
		goto nopage;
2601

2602 2603 2604 2605
	/* Try direct reclaim and then allocating */
	page = __alloc_pages_direct_reclaim(gfp_mask, order,
					zonelist, high_zoneidx,
					nodemask,
2606
					alloc_flags, preferred_zone,
2607
					migratetype, &did_some_progress);
2608 2609
	if (page)
		goto got_pg;
L
Linus Torvalds 已提交
2610

2611
	/*
2612 2613
	 * If we failed to make any progress reclaiming, then we are
	 * running out of options and have to consider going OOM
2614
	 */
2615
	if (!did_some_progress) {
2616
		if (oom_gfp_allowed(gfp_mask)) {
2617 2618
			if (oom_killer_disabled)
				goto nopage;
2619 2620 2621 2622
			/* Coredumps can quickly deplete all memory reserves */
			if ((current->flags & PF_DUMPCORE) &&
			    !(gfp_mask & __GFP_NOFAIL))
				goto nopage;
2623 2624
			page = __alloc_pages_may_oom(gfp_mask, order,
					zonelist, high_zoneidx,
2625 2626
					nodemask, preferred_zone,
					migratetype);
2627 2628
			if (page)
				goto got_pg;
L
Linus Torvalds 已提交
2629

2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646
			if (!(gfp_mask & __GFP_NOFAIL)) {
				/*
				 * The oom killer is not called for high-order
				 * allocations that may fail, so if no progress
				 * is being made, there are no other options and
				 * retrying is unlikely to help.
				 */
				if (order > PAGE_ALLOC_COSTLY_ORDER)
					goto nopage;
				/*
				 * The oom killer is not called for lowmem
				 * allocations to prevent needlessly killing
				 * innocent tasks.
				 */
				if (high_zoneidx < ZONE_NORMAL)
					goto nopage;
			}
2647

2648 2649
			goto restart;
		}
L
Linus Torvalds 已提交
2650 2651
	}

2652
	/* Check if we should retry the allocation */
2653
	pages_reclaimed += did_some_progress;
2654 2655
	if (should_alloc_retry(gfp_mask, order, did_some_progress,
						pages_reclaimed)) {
2656
		/* Wait for some write requests to complete then retry */
2657
		wait_iff_congested(preferred_zone, BLK_RW_ASYNC, HZ/50);
L
Linus Torvalds 已提交
2658
		goto rebalance;
2659 2660 2661 2662 2663 2664 2665 2666 2667 2668
	} else {
		/*
		 * High-order allocations do not necessarily loop after
		 * direct reclaim and reclaim/compaction depends on compaction
		 * being called after reclaim so call directly if necessary
		 */
		page = __alloc_pages_direct_compact(gfp_mask, order,
					zonelist, high_zoneidx,
					nodemask,
					alloc_flags, preferred_zone,
2669
					migratetype, sync_migration,
2670
					&contended_compaction,
2671 2672
					&deferred_compaction,
					&did_some_progress);
2673 2674
		if (page)
			goto got_pg;
L
Linus Torvalds 已提交
2675 2676 2677
	}

nopage:
2678
	warn_alloc_failed(gfp_mask, order, NULL);
2679
	return page;
L
Linus Torvalds 已提交
2680
got_pg:
2681 2682
	if (kmemcheck_enabled)
		kmemcheck_pagealloc_alloc(page, order, gfp_mask);
2683

2684
	return page;
L
Linus Torvalds 已提交
2685
}
2686 2687 2688 2689 2690 2691 2692 2693 2694

/*
 * 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)
{
	enum zone_type high_zoneidx = gfp_zone(gfp_mask);
2695
	struct zone *preferred_zone;
2696
	struct page *page = NULL;
2697
	int migratetype = allocflags_to_migratetype(gfp_mask);
2698
	unsigned int cpuset_mems_cookie;
2699
	int alloc_flags = ALLOC_WMARK_LOW|ALLOC_CPUSET|ALLOC_FAIR;
2700
	struct mem_cgroup *memcg = NULL;
2701

2702 2703
	gfp_mask &= gfp_allowed_mask;

2704 2705 2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718
	lockdep_trace_alloc(gfp_mask);

	might_sleep_if(gfp_mask & __GFP_WAIT);

	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;

2719 2720 2721 2722 2723 2724 2725
	/*
	 * Will only have any effect when __GFP_KMEMCG is set.  This is
	 * verified in the (always inline) callee
	 */
	if (!memcg_kmem_newpage_charge(gfp_mask, &memcg, order))
		return NULL;

2726
retry_cpuset:
2727
	cpuset_mems_cookie = read_mems_allowed_begin();
2728

2729
	/* The preferred zone is used for statistics later */
2730 2731 2732
	first_zones_zonelist(zonelist, high_zoneidx,
				nodemask ? : &cpuset_current_mems_allowed,
				&preferred_zone);
2733 2734
	if (!preferred_zone)
		goto out;
2735

2736 2737 2738 2739
#ifdef CONFIG_CMA
	if (allocflags_to_migratetype(gfp_mask) == MIGRATE_MOVABLE)
		alloc_flags |= ALLOC_CMA;
#endif
2740
retry:
2741
	/* First allocation attempt */
2742
	page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order,
2743
			zonelist, high_zoneidx, alloc_flags,
2744
			preferred_zone, migratetype);
2745
	if (unlikely(!page)) {
2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761
		/*
		 * The first pass makes sure allocations are spread
		 * fairly within the local node.  However, the local
		 * node might have free pages left after the fairness
		 * batches are exhausted, and remote zones haven't
		 * even been considered yet.  Try once more without
		 * fairness, and include remote zones now, before
		 * entering the slowpath and waking kswapd: prefer
		 * spilling to a remote zone over swapping locally.
		 */
		if (alloc_flags & ALLOC_FAIR) {
			reset_alloc_batches(zonelist, high_zoneidx,
					    preferred_zone);
			alloc_flags &= ~ALLOC_FAIR;
			goto retry;
		}
2762 2763 2764 2765 2766 2767
		/*
		 * Runtime PM, block IO and its error handling path
		 * can deadlock because I/O on the device might not
		 * complete.
		 */
		gfp_mask = memalloc_noio_flags(gfp_mask);
2768
		page = __alloc_pages_slowpath(gfp_mask, order,
2769
				zonelist, high_zoneidx, nodemask,
2770
				preferred_zone, migratetype);
2771
	}
2772

2773
	trace_mm_page_alloc(page, order, gfp_mask, migratetype);
2774 2775 2776 2777 2778 2779 2780 2781

out:
	/*
	 * 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.
	 */
2782
	if (unlikely(!page && read_mems_allowed_retry(cpuset_mems_cookie)))
2783 2784
		goto retry_cpuset;

2785 2786
	memcg_kmem_commit_charge(page, memcg, order);

2787
	return page;
L
Linus Torvalds 已提交
2788
}
2789
EXPORT_SYMBOL(__alloc_pages_nodemask);
L
Linus Torvalds 已提交
2790 2791 2792 2793

/*
 * Common helper functions.
 */
H
Harvey Harrison 已提交
2794
unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order)
L
Linus Torvalds 已提交
2795
{
2796 2797 2798 2799 2800 2801 2802 2803
	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);

L
Linus Torvalds 已提交
2804 2805 2806 2807 2808 2809 2810
	page = alloc_pages(gfp_mask, order);
	if (!page)
		return 0;
	return (unsigned long) page_address(page);
}
EXPORT_SYMBOL(__get_free_pages);

H
Harvey Harrison 已提交
2811
unsigned long get_zeroed_page(gfp_t gfp_mask)
L
Linus Torvalds 已提交
2812
{
2813
	return __get_free_pages(gfp_mask | __GFP_ZERO, 0);
L
Linus Torvalds 已提交
2814 2815 2816
}
EXPORT_SYMBOL(get_zeroed_page);

H
Harvey Harrison 已提交
2817
void __free_pages(struct page *page, unsigned int order)
L
Linus Torvalds 已提交
2818
{
N
Nick Piggin 已提交
2819
	if (put_page_testzero(page)) {
L
Linus Torvalds 已提交
2820
		if (order == 0)
L
Li Hong 已提交
2821
			free_hot_cold_page(page, 0);
L
Linus Torvalds 已提交
2822 2823 2824 2825 2826 2827 2828
		else
			__free_pages_ok(page, order);
	}
}

EXPORT_SYMBOL(__free_pages);

H
Harvey Harrison 已提交
2829
void free_pages(unsigned long addr, unsigned int order)
L
Linus Torvalds 已提交
2830 2831
{
	if (addr != 0) {
N
Nick Piggin 已提交
2832
		VM_BUG_ON(!virt_addr_valid((void *)addr));
L
Linus Torvalds 已提交
2833 2834 2835 2836 2837 2838
		__free_pages(virt_to_page((void *)addr), order);
	}
}

EXPORT_SYMBOL(free_pages);

2839 2840 2841 2842 2843 2844 2845 2846 2847 2848 2849 2850 2851 2852 2853 2854 2855 2856 2857 2858 2859 2860 2861 2862 2863
/*
 * __free_memcg_kmem_pages and free_memcg_kmem_pages will free
 * pages allocated with __GFP_KMEMCG.
 *
 * Those pages are accounted to a particular memcg, embedded in the
 * corresponding page_cgroup. To avoid adding a hit in the allocator to search
 * for that information only to find out that it is NULL for users who have no
 * interest in that whatsoever, we provide these functions.
 *
 * The caller knows better which flags it relies on.
 */
void __free_memcg_kmem_pages(struct page *page, unsigned int order)
{
	memcg_kmem_uncharge_pages(page, order);
	__free_pages(page, order);
}

void free_memcg_kmem_pages(unsigned long addr, unsigned int order)
{
	if (addr != 0) {
		VM_BUG_ON(!virt_addr_valid((void *)addr));
		__free_memcg_kmem_pages(virt_to_page((void *)addr), order);
	}
}

A
Andi Kleen 已提交
2864 2865 2866 2867 2868 2869 2870 2871 2872 2873 2874 2875 2876 2877 2878
static void *make_alloc_exact(unsigned long addr, unsigned 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;
}

2879 2880 2881 2882 2883 2884 2885 2886 2887 2888 2889 2890 2891 2892 2893 2894 2895 2896 2897
/**
 * 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);
A
Andi Kleen 已提交
2898
	return make_alloc_exact(addr, order, size);
2899 2900 2901
}
EXPORT_SYMBOL(alloc_pages_exact);

A
Andi Kleen 已提交
2902 2903 2904
/**
 * alloc_pages_exact_nid - allocate an exact number of physically-contiguous
 *			   pages on a node.
2905
 * @nid: the preferred node ID where memory should be allocated
A
Andi Kleen 已提交
2906 2907 2908 2909 2910 2911 2912 2913 2914 2915 2916 2917 2918 2919 2920 2921 2922 2923
 * @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.
 * Note this is not alloc_pages_exact_node() which allocates on a specific node,
 * but is not exact.
 */
void *alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask)
{
	unsigned 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);
}
EXPORT_SYMBOL(alloc_pages_exact_nid);

2924 2925 2926 2927 2928 2929 2930 2931 2932 2933 2934 2935 2936 2937 2938 2939 2940 2941 2942
/**
 * 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);

2943 2944 2945 2946 2947 2948 2949
/**
 * 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:
2950
 *     managed_pages - high_pages
2951
 */
2952
static unsigned long nr_free_zone_pages(int offset)
L
Linus Torvalds 已提交
2953
{
2954
	struct zoneref *z;
2955 2956
	struct zone *zone;

2957
	/* Just pick one node, since fallback list is circular */
2958
	unsigned long sum = 0;
L
Linus Torvalds 已提交
2959

2960
	struct zonelist *zonelist = node_zonelist(numa_node_id(), GFP_KERNEL);
L
Linus Torvalds 已提交
2961

2962
	for_each_zone_zonelist(zone, z, zonelist, offset) {
2963
		unsigned long size = zone->managed_pages;
2964
		unsigned long high = high_wmark_pages(zone);
2965 2966
		if (size > high)
			sum += size - high;
L
Linus Torvalds 已提交
2967 2968 2969 2970 2971
	}

	return sum;
}

2972 2973 2974 2975 2976
/**
 * 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.
L
Linus Torvalds 已提交
2977
 */
2978
unsigned long nr_free_buffer_pages(void)
L
Linus Torvalds 已提交
2979
{
A
Al Viro 已提交
2980
	return nr_free_zone_pages(gfp_zone(GFP_USER));
L
Linus Torvalds 已提交
2981
}
2982
EXPORT_SYMBOL_GPL(nr_free_buffer_pages);
L
Linus Torvalds 已提交
2983

2984 2985 2986 2987 2988
/**
 * 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.
L
Linus Torvalds 已提交
2989
 */
2990
unsigned long nr_free_pagecache_pages(void)
L
Linus Torvalds 已提交
2991
{
M
Mel Gorman 已提交
2992
	return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE));
L
Linus Torvalds 已提交
2993
}
2994 2995

static inline void show_node(struct zone *zone)
L
Linus Torvalds 已提交
2996
{
2997
	if (IS_ENABLED(CONFIG_NUMA))
2998
		printk("Node %d ", zone_to_nid(zone));
L
Linus Torvalds 已提交
2999 3000 3001 3002 3003 3004
}

void si_meminfo(struct sysinfo *val)
{
	val->totalram = totalram_pages;
	val->sharedram = 0;
3005
	val->freeram = global_page_state(NR_FREE_PAGES);
L
Linus Torvalds 已提交
3006 3007 3008 3009 3010 3011 3012 3013 3014 3015 3016
	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)
{
3017 3018
	int zone_type;		/* needs to be signed */
	unsigned long managed_pages = 0;
L
Linus Torvalds 已提交
3019 3020
	pg_data_t *pgdat = NODE_DATA(nid);

3021 3022 3023
	for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++)
		managed_pages += pgdat->node_zones[zone_type].managed_pages;
	val->totalram = managed_pages;
3024
	val->freeram = node_page_state(nid, NR_FREE_PAGES);
3025
#ifdef CONFIG_HIGHMEM
3026
	val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].managed_pages;
3027 3028
	val->freehigh = zone_page_state(&pgdat->node_zones[ZONE_HIGHMEM],
			NR_FREE_PAGES);
3029 3030 3031 3032
#else
	val->totalhigh = 0;
	val->freehigh = 0;
#endif
L
Linus Torvalds 已提交
3033 3034 3035 3036
	val->mem_unit = PAGE_SIZE;
}
#endif

3037
/*
3038 3039
 * Determine whether the node should be displayed or not, depending on whether
 * SHOW_MEM_FILTER_NODES was passed to show_free_areas().
3040
 */
3041
bool skip_free_areas_node(unsigned int flags, int nid)
3042 3043
{
	bool ret = false;
3044
	unsigned int cpuset_mems_cookie;
3045 3046 3047 3048

	if (!(flags & SHOW_MEM_FILTER_NODES))
		goto out;

3049
	do {
3050
		cpuset_mems_cookie = read_mems_allowed_begin();
3051
		ret = !node_isset(nid, cpuset_current_mems_allowed);
3052
	} while (read_mems_allowed_retry(cpuset_mems_cookie));
3053 3054 3055 3056
out:
	return ret;
}

L
Linus Torvalds 已提交
3057 3058
#define K(x) ((x) << (PAGE_SHIFT-10))

3059 3060 3061 3062 3063 3064 3065 3066 3067 3068
static void show_migration_types(unsigned char type)
{
	static const char types[MIGRATE_TYPES] = {
		[MIGRATE_UNMOVABLE]	= 'U',
		[MIGRATE_RECLAIMABLE]	= 'E',
		[MIGRATE_MOVABLE]	= 'M',
		[MIGRATE_RESERVE]	= 'R',
#ifdef CONFIG_CMA
		[MIGRATE_CMA]		= 'C',
#endif
3069
#ifdef CONFIG_MEMORY_ISOLATION
3070
		[MIGRATE_ISOLATE]	= 'I',
3071
#endif
3072 3073 3074 3075 3076 3077 3078 3079 3080 3081 3082 3083 3084 3085
	};
	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("(%s) ", tmp);
}

L
Linus Torvalds 已提交
3086 3087 3088 3089
/*
 * 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.
3090 3091
 * Suppresses nodes that are not allowed by current's cpuset if
 * SHOW_MEM_FILTER_NODES is passed.
L
Linus Torvalds 已提交
3092
 */
3093
void show_free_areas(unsigned int filter)
L
Linus Torvalds 已提交
3094
{
3095
	int cpu;
L
Linus Torvalds 已提交
3096 3097
	struct zone *zone;

3098
	for_each_populated_zone(zone) {
3099
		if (skip_free_areas_node(filter, zone_to_nid(zone)))
3100
			continue;
3101 3102
		show_node(zone);
		printk("%s per-cpu:\n", zone->name);
L
Linus Torvalds 已提交
3103

3104
		for_each_online_cpu(cpu) {
L
Linus Torvalds 已提交
3105 3106
			struct per_cpu_pageset *pageset;

3107
			pageset = per_cpu_ptr(zone->pageset, cpu);
L
Linus Torvalds 已提交
3108

3109 3110 3111
			printk("CPU %4d: hi:%5d, btch:%4d usd:%4d\n",
			       cpu, pageset->pcp.high,
			       pageset->pcp.batch, pageset->pcp.count);
L
Linus Torvalds 已提交
3112 3113 3114
		}
	}

K
KOSAKI Motohiro 已提交
3115 3116
	printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n"
		" active_file:%lu inactive_file:%lu isolated_file:%lu\n"
L
Lee Schermerhorn 已提交
3117
		" unevictable:%lu"
3118
		" dirty:%lu writeback:%lu unstable:%lu\n"
3119
		" free:%lu slab_reclaimable:%lu slab_unreclaimable:%lu\n"
3120 3121
		" mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n"
		" free_cma:%lu\n",
3122 3123
		global_page_state(NR_ACTIVE_ANON),
		global_page_state(NR_INACTIVE_ANON),
K
KOSAKI Motohiro 已提交
3124 3125
		global_page_state(NR_ISOLATED_ANON),
		global_page_state(NR_ACTIVE_FILE),
3126
		global_page_state(NR_INACTIVE_FILE),
K
KOSAKI Motohiro 已提交
3127
		global_page_state(NR_ISOLATED_FILE),
L
Lee Schermerhorn 已提交
3128
		global_page_state(NR_UNEVICTABLE),
3129
		global_page_state(NR_FILE_DIRTY),
3130
		global_page_state(NR_WRITEBACK),
3131
		global_page_state(NR_UNSTABLE_NFS),
3132
		global_page_state(NR_FREE_PAGES),
3133 3134
		global_page_state(NR_SLAB_RECLAIMABLE),
		global_page_state(NR_SLAB_UNRECLAIMABLE),
3135
		global_page_state(NR_FILE_MAPPED),
3136
		global_page_state(NR_SHMEM),
3137
		global_page_state(NR_PAGETABLE),
3138 3139
		global_page_state(NR_BOUNCE),
		global_page_state(NR_FREE_CMA_PAGES));
L
Linus Torvalds 已提交
3140

3141
	for_each_populated_zone(zone) {
L
Linus Torvalds 已提交
3142 3143
		int i;

3144
		if (skip_free_areas_node(filter, zone_to_nid(zone)))
3145
			continue;
L
Linus Torvalds 已提交
3146 3147 3148 3149 3150 3151
		show_node(zone);
		printk("%s"
			" free:%lukB"
			" min:%lukB"
			" low:%lukB"
			" high:%lukB"
3152 3153 3154 3155
			" active_anon:%lukB"
			" inactive_anon:%lukB"
			" active_file:%lukB"
			" inactive_file:%lukB"
L
Lee Schermerhorn 已提交
3156
			" unevictable:%lukB"
K
KOSAKI Motohiro 已提交
3157 3158
			" isolated(anon):%lukB"
			" isolated(file):%lukB"
L
Linus Torvalds 已提交
3159
			" present:%lukB"
3160
			" managed:%lukB"
3161 3162 3163 3164
			" mlocked:%lukB"
			" dirty:%lukB"
			" writeback:%lukB"
			" mapped:%lukB"
3165
			" shmem:%lukB"
3166 3167
			" slab_reclaimable:%lukB"
			" slab_unreclaimable:%lukB"
3168
			" kernel_stack:%lukB"
3169 3170 3171
			" pagetables:%lukB"
			" unstable:%lukB"
			" bounce:%lukB"
3172
			" free_cma:%lukB"
3173
			" writeback_tmp:%lukB"
L
Linus Torvalds 已提交
3174 3175 3176 3177
			" pages_scanned:%lu"
			" all_unreclaimable? %s"
			"\n",
			zone->name,
3178
			K(zone_page_state(zone, NR_FREE_PAGES)),
3179 3180 3181
			K(min_wmark_pages(zone)),
			K(low_wmark_pages(zone)),
			K(high_wmark_pages(zone)),
3182 3183 3184 3185
			K(zone_page_state(zone, NR_ACTIVE_ANON)),
			K(zone_page_state(zone, NR_INACTIVE_ANON)),
			K(zone_page_state(zone, NR_ACTIVE_FILE)),
			K(zone_page_state(zone, NR_INACTIVE_FILE)),
L
Lee Schermerhorn 已提交
3186
			K(zone_page_state(zone, NR_UNEVICTABLE)),
K
KOSAKI Motohiro 已提交
3187 3188
			K(zone_page_state(zone, NR_ISOLATED_ANON)),
			K(zone_page_state(zone, NR_ISOLATED_FILE)),
L
Linus Torvalds 已提交
3189
			K(zone->present_pages),
3190
			K(zone->managed_pages),
3191 3192 3193 3194
			K(zone_page_state(zone, NR_MLOCK)),
			K(zone_page_state(zone, NR_FILE_DIRTY)),
			K(zone_page_state(zone, NR_WRITEBACK)),
			K(zone_page_state(zone, NR_FILE_MAPPED)),
3195
			K(zone_page_state(zone, NR_SHMEM)),
3196 3197
			K(zone_page_state(zone, NR_SLAB_RECLAIMABLE)),
			K(zone_page_state(zone, NR_SLAB_UNRECLAIMABLE)),
3198 3199
			zone_page_state(zone, NR_KERNEL_STACK) *
				THREAD_SIZE / 1024,
3200 3201 3202
			K(zone_page_state(zone, NR_PAGETABLE)),
			K(zone_page_state(zone, NR_UNSTABLE_NFS)),
			K(zone_page_state(zone, NR_BOUNCE)),
3203
			K(zone_page_state(zone, NR_FREE_CMA_PAGES)),
3204
			K(zone_page_state(zone, NR_WRITEBACK_TEMP)),
L
Linus Torvalds 已提交
3205
			zone->pages_scanned,
3206
			(!zone_reclaimable(zone) ? "yes" : "no")
L
Linus Torvalds 已提交
3207 3208 3209 3210 3211 3212 3213
			);
		printk("lowmem_reserve[]:");
		for (i = 0; i < MAX_NR_ZONES; i++)
			printk(" %lu", zone->lowmem_reserve[i]);
		printk("\n");
	}

3214
	for_each_populated_zone(zone) {
3215
		unsigned long nr[MAX_ORDER], flags, order, total = 0;
3216
		unsigned char types[MAX_ORDER];
L
Linus Torvalds 已提交
3217

3218
		if (skip_free_areas_node(filter, zone_to_nid(zone)))
3219
			continue;
L
Linus Torvalds 已提交
3220 3221 3222 3223 3224
		show_node(zone);
		printk("%s: ", zone->name);

		spin_lock_irqsave(&zone->lock, flags);
		for (order = 0; order < MAX_ORDER; order++) {
3225 3226 3227 3228
			struct free_area *area = &zone->free_area[order];
			int type;

			nr[order] = area->nr_free;
3229
			total += nr[order] << order;
3230 3231 3232 3233 3234 3235

			types[order] = 0;
			for (type = 0; type < MIGRATE_TYPES; type++) {
				if (!list_empty(&area->free_list[type]))
					types[order] |= 1 << type;
			}
L
Linus Torvalds 已提交
3236 3237
		}
		spin_unlock_irqrestore(&zone->lock, flags);
3238
		for (order = 0; order < MAX_ORDER; order++) {
3239
			printk("%lu*%lukB ", nr[order], K(1UL) << order);
3240 3241 3242
			if (nr[order])
				show_migration_types(types[order]);
		}
L
Linus Torvalds 已提交
3243 3244 3245
		printk("= %lukB\n", K(total));
	}

3246 3247
	hugetlb_show_meminfo();

3248 3249
	printk("%ld total pagecache pages\n", global_page_state(NR_FILE_PAGES));

L
Linus Torvalds 已提交
3250 3251 3252
	show_swap_cache_info();
}

3253 3254 3255 3256 3257 3258
static void zoneref_set_zone(struct zone *zone, struct zoneref *zoneref)
{
	zoneref->zone = zone;
	zoneref->zone_idx = zone_idx(zone);
}

L
Linus Torvalds 已提交
3259 3260
/*
 * Builds allocation fallback zone lists.
3261 3262
 *
 * Add all populated zones of a node to the zonelist.
L
Linus Torvalds 已提交
3263
 */
3264
static int build_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist,
3265
				int nr_zones)
L
Linus Torvalds 已提交
3266
{
3267
	struct zone *zone;
3268
	enum zone_type zone_type = MAX_NR_ZONES;
3269 3270

	do {
3271
		zone_type--;
3272
		zone = pgdat->node_zones + zone_type;
3273
		if (populated_zone(zone)) {
3274 3275
			zoneref_set_zone(zone,
				&zonelist->_zonerefs[nr_zones++]);
3276
			check_highest_zone(zone_type);
L
Linus Torvalds 已提交
3277
		}
3278
	} while (zone_type);
3279

3280
	return nr_zones;
L
Linus Torvalds 已提交
3281 3282
}

3283 3284 3285 3286 3287 3288 3289 3290 3291 3292 3293 3294 3295 3296 3297 3298 3299 3300 3301 3302 3303

/*
 *  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"};


L
Linus Torvalds 已提交
3304
#ifdef CONFIG_NUMA
3305 3306 3307 3308 3309 3310 3311 3312 3313 3314 3315 3316 3317 3318 3319 3320 3321 3322 3323 3324 3325 3326 3327 3328 3329 3330 3331 3332 3333 3334 3335 3336 3337
/* 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 {
		printk(KERN_WARNING
			"Ignoring invalid numa_zonelist_order value:  "
			"%s\n", s);
		return -EINVAL;
	}
	return 0;
}

static __init int setup_numa_zonelist_order(char *s)
{
3338 3339 3340 3341 3342 3343 3344 3345 3346 3347
	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;
3348 3349 3350 3351 3352 3353 3354
}
early_param("numa_zonelist_order", setup_numa_zonelist_order);

/*
 * sysctl handler for numa_zonelist_order
 */
int numa_zonelist_order_handler(ctl_table *table, int write,
3355
		void __user *buffer, size_t *length,
3356 3357 3358 3359
		loff_t *ppos)
{
	char saved_string[NUMA_ZONELIST_ORDER_LEN];
	int ret;
3360
	static DEFINE_MUTEX(zl_order_mutex);
3361

3362
	mutex_lock(&zl_order_mutex);
3363 3364 3365 3366 3367 3368 3369
	if (write) {
		if (strlen((char *)table->data) >= NUMA_ZONELIST_ORDER_LEN) {
			ret = -EINVAL;
			goto out;
		}
		strcpy(saved_string, (char *)table->data);
	}
3370
	ret = proc_dostring(table, write, buffer, length, ppos);
3371
	if (ret)
3372
		goto out;
3373 3374
	if (write) {
		int oldval = user_zonelist_order;
3375 3376 3377

		ret = __parse_numa_zonelist_order((char *)table->data);
		if (ret) {
3378 3379 3380
			/*
			 * bogus value.  restore saved string
			 */
3381
			strncpy((char *)table->data, saved_string,
3382 3383
				NUMA_ZONELIST_ORDER_LEN);
			user_zonelist_order = oldval;
3384 3385
		} else if (oldval != user_zonelist_order) {
			mutex_lock(&zonelists_mutex);
3386
			build_all_zonelists(NULL, NULL);
3387 3388
			mutex_unlock(&zonelists_mutex);
		}
3389
	}
3390 3391 3392
out:
	mutex_unlock(&zl_order_mutex);
	return ret;
3393 3394 3395
}


3396
#define MAX_NODE_LOAD (nr_online_nodes)
3397 3398
static int node_load[MAX_NUMNODES];

L
Linus Torvalds 已提交
3399
/**
3400
 * find_next_best_node - find the next node that should appear in a given node's fallback list
L
Linus Torvalds 已提交
3401 3402 3403 3404 3405 3406 3407 3408 3409 3410 3411 3412
 * @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.
 */
3413
static int find_next_best_node(int node, nodemask_t *used_node_mask)
L
Linus Torvalds 已提交
3414
{
3415
	int n, val;
L
Linus Torvalds 已提交
3416
	int min_val = INT_MAX;
D
David Rientjes 已提交
3417
	int best_node = NUMA_NO_NODE;
3418
	const struct cpumask *tmp = cpumask_of_node(0);
L
Linus Torvalds 已提交
3419

3420 3421 3422 3423 3424
	/* Use the local node if we haven't already */
	if (!node_isset(node, *used_node_mask)) {
		node_set(node, *used_node_mask);
		return node;
	}
L
Linus Torvalds 已提交
3425

3426
	for_each_node_state(n, N_MEMORY) {
L
Linus Torvalds 已提交
3427 3428 3429 3430 3431 3432 3433 3434

		/* 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);

3435 3436 3437
		/* Penalize nodes under us ("prefer the next node") */
		val += (n < node);

L
Linus Torvalds 已提交
3438
		/* Give preference to headless and unused nodes */
3439 3440
		tmp = cpumask_of_node(n);
		if (!cpumask_empty(tmp))
L
Linus Torvalds 已提交
3441 3442 3443 3444 3445 3446 3447 3448 3449 3450 3451 3452 3453 3454 3455 3456 3457 3458
			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;
}

3459 3460 3461 3462 3463 3464 3465

/*
 * 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)
L
Linus Torvalds 已提交
3466
{
3467
	int j;
L
Linus Torvalds 已提交
3468
	struct zonelist *zonelist;
3469

3470
	zonelist = &pgdat->node_zonelists[0];
3471
	for (j = 0; zonelist->_zonerefs[j].zone != NULL; j++)
3472
		;
3473
	j = build_zonelists_node(NODE_DATA(node), zonelist, j);
3474 3475
	zonelist->_zonerefs[j].zone = NULL;
	zonelist->_zonerefs[j].zone_idx = 0;
3476 3477
}

3478 3479 3480 3481 3482 3483 3484 3485
/*
 * Build gfp_thisnode zonelists
 */
static void build_thisnode_zonelists(pg_data_t *pgdat)
{
	int j;
	struct zonelist *zonelist;

3486
	zonelist = &pgdat->node_zonelists[1];
3487
	j = build_zonelists_node(pgdat, zonelist, 0);
3488 3489
	zonelist->_zonerefs[j].zone = NULL;
	zonelist->_zonerefs[j].zone_idx = 0;
3490 3491
}

3492 3493 3494 3495 3496 3497 3498 3499 3500 3501 3502 3503 3504 3505 3506
/*
 * 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;

3507 3508 3509 3510 3511 3512 3513
	zonelist = &pgdat->node_zonelists[0];
	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 (populated_zone(z)) {
3514 3515
				zoneref_set_zone(z,
					&zonelist->_zonerefs[pos++]);
3516
				check_highest_zone(zone_type);
3517 3518 3519
			}
		}
	}
3520 3521
	zonelist->_zonerefs[pos].zone = NULL;
	zonelist->_zonerefs[pos].zone_idx = 0;
3522 3523 3524 3525 3526
}

static int default_zonelist_order(void)
{
	int nid, zone_type;
3527
	unsigned long low_kmem_size, total_size;
3528 3529 3530
	struct zone *z;
	int average_size;
	/*
3531
	 * ZONE_DMA and ZONE_DMA32 can be very small area in the system.
3532 3533
	 * If they are really small and used heavily, the system can fall
	 * into OOM very easily.
3534
	 * This function detect ZONE_DMA/DMA32 size and configures zone order.
3535 3536 3537 3538 3539 3540 3541 3542 3543
	 */
	/* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */
	low_kmem_size = 0;
	total_size = 0;
	for_each_online_node(nid) {
		for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) {
			z = &NODE_DATA(nid)->node_zones[zone_type];
			if (populated_zone(z)) {
				if (zone_type < ZONE_NORMAL)
3544 3545
					low_kmem_size += z->managed_pages;
				total_size += z->managed_pages;
3546 3547 3548 3549 3550 3551 3552 3553 3554
			} else if (zone_type == ZONE_NORMAL) {
				/*
				 * If any node has only lowmem, then node order
				 * is preferred to allow kernel allocations
				 * locally; otherwise, they can easily infringe
				 * on other nodes when there is an abundance of
				 * lowmem available to allocate from.
				 */
				return ZONELIST_ORDER_NODE;
3555 3556 3557 3558 3559 3560 3561 3562
			}
		}
	}
	if (!low_kmem_size ||  /* there are no DMA area. */
	    low_kmem_size > total_size/2) /* DMA/DMA32 is big. */
		return ZONELIST_ORDER_NODE;
	/*
	 * look into each node's config.
3563 3564 3565
	 * If there is a node whose DMA/DMA32 memory is very big area on
	 * local memory, NODE_ORDER may be suitable.
	 */
3566
	average_size = total_size /
3567
				(nodes_weight(node_states[N_MEMORY]) + 1);
3568 3569 3570 3571 3572 3573 3574 3575 3576 3577 3578 3579 3580 3581 3582 3583 3584 3585 3586 3587 3588 3589 3590 3591 3592 3593 3594 3595 3596 3597 3598
	for_each_online_node(nid) {
		low_kmem_size = 0;
		total_size = 0;
		for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) {
			z = &NODE_DATA(nid)->node_zones[zone_type];
			if (populated_zone(z)) {
				if (zone_type < ZONE_NORMAL)
					low_kmem_size += z->present_pages;
				total_size += z->present_pages;
			}
		}
		if (low_kmem_size &&
		    total_size > average_size && /* ignore small node */
		    low_kmem_size > total_size * 70/100)
			return ZONELIST_ORDER_NODE;
	}
	return ZONELIST_ORDER_ZONE;
}

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 j, node, load;
	enum zone_type i;
L
Linus Torvalds 已提交
3599
	nodemask_t used_mask;
3600 3601 3602
	int local_node, prev_node;
	struct zonelist *zonelist;
	int order = current_zonelist_order;
L
Linus Torvalds 已提交
3603 3604

	/* initialize zonelists */
3605
	for (i = 0; i < MAX_ZONELISTS; i++) {
L
Linus Torvalds 已提交
3606
		zonelist = pgdat->node_zonelists + i;
3607 3608
		zonelist->_zonerefs[0].zone = NULL;
		zonelist->_zonerefs[0].zone_idx = 0;
L
Linus Torvalds 已提交
3609 3610 3611 3612
	}

	/* NUMA-aware ordering of nodes */
	local_node = pgdat->node_id;
3613
	load = nr_online_nodes;
L
Linus Torvalds 已提交
3614 3615
	prev_node = local_node;
	nodes_clear(used_mask);
3616 3617 3618 3619

	memset(node_order, 0, sizeof(node_order));
	j = 0;

L
Linus Torvalds 已提交
3620 3621 3622 3623 3624 3625
	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.
		 */
3626 3627
		if (node_distance(local_node, node) !=
		    node_distance(local_node, prev_node))
3628 3629
			node_load[node] = load;

L
Linus Torvalds 已提交
3630 3631
		prev_node = node;
		load--;
3632 3633 3634 3635 3636
		if (order == ZONELIST_ORDER_NODE)
			build_zonelists_in_node_order(pgdat, node);
		else
			node_order[j++] = node;	/* remember order */
	}
L
Linus Torvalds 已提交
3637

3638 3639 3640
	if (order == ZONELIST_ORDER_ZONE) {
		/* calculate node order -- i.e., DMA last! */
		build_zonelists_in_zone_order(pgdat, j);
L
Linus Torvalds 已提交
3641
	}
3642 3643

	build_thisnode_zonelists(pgdat);
L
Linus Torvalds 已提交
3644 3645
}

3646
/* Construct the zonelist performance cache - see further mmzone.h */
3647
static void build_zonelist_cache(pg_data_t *pgdat)
3648
{
3649 3650
	struct zonelist *zonelist;
	struct zonelist_cache *zlc;
3651
	struct zoneref *z;
3652

3653 3654 3655
	zonelist = &pgdat->node_zonelists[0];
	zonelist->zlcache_ptr = zlc = &zonelist->zlcache;
	bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST);
3656 3657
	for (z = zonelist->_zonerefs; z->zone; z++)
		zlc->z_to_n[z - zonelist->_zonerefs] = zonelist_node_idx(z);
3658 3659
}

3660 3661 3662 3663 3664 3665 3666 3667 3668 3669 3670 3671 3672 3673 3674 3675 3676 3677
#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 zone *zone;

	(void)first_zones_zonelist(node_zonelist(node, GFP_KERNEL),
				   gfp_zone(GFP_KERNEL),
				   NULL,
				   &zone);
	return zone->node;
}
#endif
3678

L
Linus Torvalds 已提交
3679 3680
#else	/* CONFIG_NUMA */

3681 3682 3683 3684 3685 3686
static void set_zonelist_order(void)
{
	current_zonelist_order = ZONELIST_ORDER_ZONE;
}

static void build_zonelists(pg_data_t *pgdat)
L
Linus Torvalds 已提交
3687
{
3688
	int node, local_node;
3689 3690
	enum zone_type j;
	struct zonelist *zonelist;
L
Linus Torvalds 已提交
3691 3692 3693

	local_node = pgdat->node_id;

3694
	zonelist = &pgdat->node_zonelists[0];
3695
	j = build_zonelists_node(pgdat, zonelist, 0);
L
Linus Torvalds 已提交
3696

3697 3698 3699 3700 3701 3702 3703 3704 3705 3706 3707
	/*
	 * 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;
3708
		j = build_zonelists_node(NODE_DATA(node), zonelist, j);
L
Linus Torvalds 已提交
3709
	}
3710 3711 3712
	for (node = 0; node < local_node; node++) {
		if (!node_online(node))
			continue;
3713
		j = build_zonelists_node(NODE_DATA(node), zonelist, j);
3714 3715
	}

3716 3717
	zonelist->_zonerefs[j].zone = NULL;
	zonelist->_zonerefs[j].zone_idx = 0;
L
Linus Torvalds 已提交
3718 3719
}

3720
/* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */
3721
static void build_zonelist_cache(pg_data_t *pgdat)
3722
{
3723
	pgdat->node_zonelists[0].zlcache_ptr = NULL;
3724 3725
}

L
Linus Torvalds 已提交
3726 3727
#endif	/* CONFIG_NUMA */

3728 3729 3730 3731 3732 3733 3734 3735 3736 3737 3738 3739 3740 3741 3742 3743 3744
/*
 * 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);
3745
static void setup_zone_pageset(struct zone *zone);
3746

3747 3748 3749 3750 3751 3752
/*
 * 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);

3753
/* return values int ....just for stop_machine() */
3754
static int __build_all_zonelists(void *data)
L
Linus Torvalds 已提交
3755
{
3756
	int nid;
3757
	int cpu;
3758
	pg_data_t *self = data;
3759

3760 3761 3762
#ifdef CONFIG_NUMA
	memset(node_load, 0, sizeof(node_load));
#endif
3763 3764 3765 3766 3767 3768

	if (self && !node_online(self->node_id)) {
		build_zonelists(self);
		build_zonelist_cache(self);
	}

3769
	for_each_online_node(nid) {
3770 3771 3772 3773
		pg_data_t *pgdat = NODE_DATA(nid);

		build_zonelists(pgdat);
		build_zonelist_cache(pgdat);
3774
	}
3775 3776 3777 3778 3779 3780 3781 3782 3783 3784 3785 3786 3787 3788

	/*
	 * 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).
	 */
3789
	for_each_possible_cpu(cpu) {
3790 3791
		setup_pageset(&per_cpu(boot_pageset, cpu), 0);

3792 3793 3794 3795 3796 3797 3798 3799 3800 3801 3802 3803 3804 3805
#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
	}

3806 3807 3808
	return 0;
}

3809 3810 3811 3812
/*
 * Called with zonelists_mutex held always
 * unless system_state == SYSTEM_BOOTING.
 */
3813
void __ref build_all_zonelists(pg_data_t *pgdat, struct zone *zone)
3814
{
3815 3816
	set_zonelist_order();

3817
	if (system_state == SYSTEM_BOOTING) {
3818
		__build_all_zonelists(NULL);
3819
		mminit_verify_zonelist();
3820 3821
		cpuset_init_current_mems_allowed();
	} else {
3822
#ifdef CONFIG_MEMORY_HOTPLUG
3823 3824
		if (zone)
			setup_zone_pageset(zone);
3825
#endif
3826 3827
		/* we have to stop all cpus to guarantee there is no user
		   of zonelist */
3828
		stop_machine(__build_all_zonelists, pgdat, NULL);
3829 3830
		/* cpuset refresh routine should be here */
	}
3831
	vm_total_pages = nr_free_pagecache_pages();
3832 3833 3834 3835 3836 3837 3838
	/*
	 * 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
	 */
3839
	if (vm_total_pages < (pageblock_nr_pages * MIGRATE_TYPES))
3840 3841 3842 3843 3844 3845
		page_group_by_mobility_disabled = 1;
	else
		page_group_by_mobility_disabled = 0;

	printk("Built %i zonelists in %s order, mobility grouping %s.  "
		"Total pages: %ld\n",
3846
			nr_online_nodes,
3847
			zonelist_order_name[current_zonelist_order],
3848
			page_group_by_mobility_disabled ? "off" : "on",
3849 3850 3851 3852
			vm_total_pages);
#ifdef CONFIG_NUMA
	printk("Policy zone: %s\n", zone_names[policy_zone]);
#endif
L
Linus Torvalds 已提交
3853 3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866 3867
}

/*
 * Helper functions to size the waitqueue hash table.
 * Essentially these want to choose hash table sizes sufficiently
 * large so that collisions trying to wait on pages are rare.
 * But in fact, the number of active page waitqueues on typical
 * systems is ridiculously low, less than 200. So this is even
 * conservative, even though it seems large.
 *
 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to
 * waitqueues, i.e. the size of the waitq table given the number of pages.
 */
#define PAGES_PER_WAITQUEUE	256

3868
#ifndef CONFIG_MEMORY_HOTPLUG
3869
static inline unsigned long wait_table_hash_nr_entries(unsigned long pages)
L
Linus Torvalds 已提交
3870 3871 3872 3873 3874 3875 3876 3877 3878 3879 3880 3881 3882 3883 3884 3885 3886
{
	unsigned long size = 1;

	pages /= PAGES_PER_WAITQUEUE;

	while (size < pages)
		size <<= 1;

	/*
	 * Once we have dozens or even hundreds of threads sleeping
	 * on IO we've got bigger problems than wait queue collision.
	 * Limit the size of the wait table to a reasonable size.
	 */
	size = min(size, 4096UL);

	return max(size, 4UL);
}
3887 3888 3889 3890 3891 3892 3893 3894 3895 3896 3897 3898 3899 3900 3901 3902 3903 3904 3905 3906 3907 3908 3909
#else
/*
 * A zone's size might be changed by hot-add, so it is not possible to determine
 * a suitable size for its wait_table.  So we use the maximum size now.
 *
 * The max wait table size = 4096 x sizeof(wait_queue_head_t).   ie:
 *
 *    i386 (preemption config)    : 4096 x 16 = 64Kbyte.
 *    ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte.
 *    ia64, x86-64 (preemption)   : 4096 x 24 = 96Kbyte.
 *
 * The maximum entries are prepared when a zone's memory is (512K + 256) pages
 * or more by the traditional way. (See above).  It equals:
 *
 *    i386, x86-64, powerpc(4K page size) : =  ( 2G + 1M)byte.
 *    ia64(16K page size)                 : =  ( 8G + 4M)byte.
 *    powerpc (64K page size)             : =  (32G +16M)byte.
 */
static inline unsigned long wait_table_hash_nr_entries(unsigned long pages)
{
	return 4096UL;
}
#endif
L
Linus Torvalds 已提交
3910 3911 3912 3913 3914 3915 3916 3917 3918 3919 3920

/*
 * This is an integer logarithm so that shifts can be used later
 * to extract the more random high bits from the multiplicative
 * hash function before the remainder is taken.
 */
static inline unsigned long wait_table_bits(unsigned long size)
{
	return ffz(~size);
}

3921 3922 3923 3924 3925 3926 3927 3928 3929 3930 3931 3932 3933 3934
/*
 * Check if a pageblock contains reserved pages
 */
static int pageblock_is_reserved(unsigned long start_pfn, unsigned long end_pfn)
{
	unsigned long pfn;

	for (pfn = start_pfn; pfn < end_pfn; pfn++) {
		if (!pfn_valid_within(pfn) || PageReserved(pfn_to_page(pfn)))
			return 1;
	}
	return 0;
}

3935
/*
3936
 * Mark a number of pageblocks as MIGRATE_RESERVE. The number
3937 3938
 * of blocks reserved is based on min_wmark_pages(zone). The memory within
 * the reserve will tend to store contiguous free pages. Setting min_free_kbytes
3939 3940 3941 3942 3943
 * higher will lead to a bigger reserve which will get freed as contiguous
 * blocks as reclaim kicks in
 */
static void setup_zone_migrate_reserve(struct zone *zone)
{
3944
	unsigned long start_pfn, pfn, end_pfn, block_end_pfn;
3945
	struct page *page;
3946 3947
	unsigned long block_migratetype;
	int reserve;
3948
	int old_reserve;
3949

3950 3951 3952 3953 3954 3955
	/*
	 * Get the start pfn, end pfn and the number of blocks to reserve
	 * We have to be careful to be aligned to pageblock_nr_pages to
	 * make sure that we always check pfn_valid for the first page in
	 * the block.
	 */
3956
	start_pfn = zone->zone_start_pfn;
3957
	end_pfn = zone_end_pfn(zone);
3958
	start_pfn = roundup(start_pfn, pageblock_nr_pages);
3959
	reserve = roundup(min_wmark_pages(zone), pageblock_nr_pages) >>
3960
							pageblock_order;
3961

3962 3963 3964 3965 3966 3967 3968 3969
	/*
	 * Reserve blocks are generally in place to help high-order atomic
	 * allocations that are short-lived. A min_free_kbytes value that
	 * would result in more than 2 reserve blocks for atomic allocations
	 * is assumed to be in place to help anti-fragmentation for the
	 * future allocation of hugepages at runtime.
	 */
	reserve = min(2, reserve);
3970 3971 3972 3973 3974 3975
	old_reserve = zone->nr_migrate_reserve_block;

	/* When memory hot-add, we almost always need to do nothing */
	if (reserve == old_reserve)
		return;
	zone->nr_migrate_reserve_block = reserve;
3976

3977
	for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) {
3978 3979 3980 3981
		if (!pfn_valid(pfn))
			continue;
		page = pfn_to_page(pfn);

3982 3983 3984 3985
		/* Watch out for overlapping nodes */
		if (page_to_nid(page) != zone_to_nid(zone))
			continue;

3986 3987
		block_migratetype = get_pageblock_migratetype(page);

3988 3989 3990 3991 3992 3993 3994 3995 3996
		/* Only test what is necessary when the reserves are not met */
		if (reserve > 0) {
			/*
			 * Blocks with reserved pages will never free, skip
			 * them.
			 */
			block_end_pfn = min(pfn + pageblock_nr_pages, end_pfn);
			if (pageblock_is_reserved(pfn, block_end_pfn))
				continue;
3997

3998 3999 4000 4001 4002 4003 4004 4005 4006 4007 4008 4009 4010 4011 4012
			/* If this block is reserved, account for it */
			if (block_migratetype == MIGRATE_RESERVE) {
				reserve--;
				continue;
			}

			/* Suitable for reserving if this block is movable */
			if (block_migratetype == MIGRATE_MOVABLE) {
				set_pageblock_migratetype(page,
							MIGRATE_RESERVE);
				move_freepages_block(zone, page,
							MIGRATE_RESERVE);
				reserve--;
				continue;
			}
4013 4014 4015 4016 4017 4018
		} else if (!old_reserve) {
			/*
			 * At boot time we don't need to scan the whole zone
			 * for turning off MIGRATE_RESERVE.
			 */
			break;
4019 4020 4021 4022 4023 4024 4025 4026 4027 4028 4029 4030
		}

		/*
		 * If the reserve is met and this is a previous reserved block,
		 * take it back
		 */
		if (block_migratetype == MIGRATE_RESERVE) {
			set_pageblock_migratetype(page, MIGRATE_MOVABLE);
			move_freepages_block(zone, page, MIGRATE_MOVABLE);
		}
	}
}
M
Mel Gorman 已提交
4031

L
Linus Torvalds 已提交
4032 4033 4034 4035 4036
/*
 * 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.
 */
4037
void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
D
Dave Hansen 已提交
4038
		unsigned long start_pfn, enum memmap_context context)
L
Linus Torvalds 已提交
4039 4040
{
	struct page *page;
A
Andy Whitcroft 已提交
4041 4042
	unsigned long end_pfn = start_pfn + size;
	unsigned long pfn;
4043
	struct zone *z;
L
Linus Torvalds 已提交
4044

4045 4046 4047
	if (highest_memmap_pfn < end_pfn - 1)
		highest_memmap_pfn = end_pfn - 1;

4048
	z = &NODE_DATA(nid)->node_zones[zone];
4049
	for (pfn = start_pfn; pfn < end_pfn; pfn++) {
D
Dave Hansen 已提交
4050 4051 4052 4053 4054 4055 4056 4057 4058 4059 4060
		/*
		 * 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) {
			if (!early_pfn_valid(pfn))
				continue;
			if (!early_pfn_in_nid(pfn, nid))
				continue;
		}
A
Andy Whitcroft 已提交
4061 4062
		page = pfn_to_page(pfn);
		set_page_links(page, zone, nid, pfn);
4063
		mminit_verify_page_links(page, zone, nid, pfn);
4064
		init_page_count(page);
4065
		page_mapcount_reset(page);
4066
		page_cpupid_reset_last(page);
L
Linus Torvalds 已提交
4067
		SetPageReserved(page);
4068 4069 4070 4071 4072
		/*
		 * 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
4073 4074 4075
		 * kernel allocations are made. Later some blocks near
		 * the start are marked MIGRATE_RESERVE by
		 * setup_zone_migrate_reserve()
4076 4077 4078 4079 4080
		 *
		 * 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.
4081
		 */
4082
		if ((z->zone_start_pfn <= pfn)
4083
		    && (pfn < zone_end_pfn(z))
4084
		    && !(pfn & (pageblock_nr_pages - 1)))
4085
			set_pageblock_migratetype(page, MIGRATE_MOVABLE);
4086

L
Linus Torvalds 已提交
4087 4088 4089 4090
		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))
4091
			set_page_address(page, __va(pfn << PAGE_SHIFT));
L
Linus Torvalds 已提交
4092 4093 4094 4095
#endif
	}
}

4096
static void __meminit zone_init_free_lists(struct zone *zone)
L
Linus Torvalds 已提交
4097
{
4098 4099 4100
	int order, t;
	for_each_migratetype_order(order, t) {
		INIT_LIST_HEAD(&zone->free_area[order].free_list[t]);
L
Linus Torvalds 已提交
4101 4102 4103 4104 4105 4106
		zone->free_area[order].nr_free = 0;
	}
}

#ifndef __HAVE_ARCH_MEMMAP_INIT
#define memmap_init(size, nid, zone, start_pfn) \
D
Dave Hansen 已提交
4107
	memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY)
L
Linus Torvalds 已提交
4108 4109
#endif

4110
static int __meminit zone_batchsize(struct zone *zone)
4111
{
4112
#ifdef CONFIG_MMU
4113 4114 4115 4116
	int batch;

	/*
	 * The per-cpu-pages pools are set to around 1000th of the
4117
	 * size of the zone.  But no more than 1/2 of a meg.
4118 4119 4120
	 *
	 * OK, so we don't know how big the cache is.  So guess.
	 */
4121
	batch = zone->managed_pages / 1024;
4122 4123
	if (batch * PAGE_SIZE > 512 * 1024)
		batch = (512 * 1024) / PAGE_SIZE;
4124 4125 4126 4127 4128
	batch /= 4;		/* We effectively *= 4 below */
	if (batch < 1)
		batch = 1;

	/*
4129 4130 4131
	 * 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.
4132
	 *
4133 4134 4135 4136
	 * 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.
4137
	 */
4138
	batch = rounddown_pow_of_two(batch + batch/2) - 1;
4139

4140
	return batch;
4141 4142 4143 4144 4145 4146 4147 4148 4149 4150 4151 4152 4153 4154 4155 4156 4157

#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
4158 4159
}

4160 4161 4162 4163 4164 4165 4166 4167 4168 4169 4170 4171 4172 4173 4174 4175 4176 4177 4178 4179 4180 4181 4182 4183 4184 4185 4186
/*
 * 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;
}

4187
/* a companion to pageset_set_high() */
4188 4189
static void pageset_set_batch(struct per_cpu_pageset *p, unsigned long batch)
{
4190
	pageset_update(&p->pcp, 6 * batch, max(1UL, 1 * batch));
4191 4192
}

4193
static void pageset_init(struct per_cpu_pageset *p)
4194 4195
{
	struct per_cpu_pages *pcp;
4196
	int migratetype;
4197

4198 4199
	memset(p, 0, sizeof(*p));

4200
	pcp = &p->pcp;
4201
	pcp->count = 0;
4202 4203
	for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++)
		INIT_LIST_HEAD(&pcp->lists[migratetype]);
4204 4205
}

4206 4207 4208 4209 4210 4211
static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch)
{
	pageset_init(p);
	pageset_set_batch(p, batch);
}

4212
/*
4213
 * pageset_set_high() sets the high water mark for hot per_cpu_pagelist
4214 4215
 * to the value high for the pageset p.
 */
4216
static void pageset_set_high(struct per_cpu_pageset *p,
4217 4218
				unsigned long high)
{
4219 4220 4221
	unsigned long batch = max(1UL, high / 4);
	if ((high / 4) > (PAGE_SHIFT * 8))
		batch = PAGE_SHIFT * 8;
4222

4223
	pageset_update(&p->pcp, high, batch);
4224 4225
}

4226 4227
static void __meminit pageset_set_high_and_batch(struct zone *zone,
		struct per_cpu_pageset *pcp)
4228 4229
{
	if (percpu_pagelist_fraction)
4230
		pageset_set_high(pcp,
4231 4232 4233 4234 4235 4236
			(zone->managed_pages /
				percpu_pagelist_fraction));
	else
		pageset_set_batch(pcp, zone_batchsize(zone));
}

4237 4238 4239 4240 4241 4242 4243 4244
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);
}

4245
static void __meminit setup_zone_pageset(struct zone *zone)
4246 4247 4248
{
	int cpu;
	zone->pageset = alloc_percpu(struct per_cpu_pageset);
4249 4250
	for_each_possible_cpu(cpu)
		zone_pageset_init(zone, cpu);
4251 4252
}

4253
/*
4254 4255
 * Allocate per cpu pagesets and initialize them.
 * Before this call only boot pagesets were available.
4256
 */
4257
void __init setup_per_cpu_pageset(void)
4258
{
4259
	struct zone *zone;
4260

4261 4262
	for_each_populated_zone(zone)
		setup_zone_pageset(zone);
4263 4264
}

S
Sam Ravnborg 已提交
4265
static noinline __init_refok
4266
int zone_wait_table_init(struct zone *zone, unsigned long zone_size_pages)
4267 4268
{
	int i;
4269
	size_t alloc_size;
4270 4271 4272 4273 4274

	/*
	 * The per-page waitqueue mechanism uses hashed waitqueues
	 * per zone.
	 */
4275 4276 4277 4278
	zone->wait_table_hash_nr_entries =
		 wait_table_hash_nr_entries(zone_size_pages);
	zone->wait_table_bits =
		wait_table_bits(zone->wait_table_hash_nr_entries);
4279 4280 4281
	alloc_size = zone->wait_table_hash_nr_entries
					* sizeof(wait_queue_head_t);

4282
	if (!slab_is_available()) {
4283
		zone->wait_table = (wait_queue_head_t *)
4284 4285
			memblock_virt_alloc_node_nopanic(
				alloc_size, zone->zone_pgdat->node_id);
4286 4287 4288 4289 4290 4291 4292 4293 4294 4295 4296
	} else {
		/*
		 * This case means that a zone whose size was 0 gets new memory
		 * via memory hot-add.
		 * But it may be the case that a new node was hot-added.  In
		 * this case vmalloc() will not be able to use this new node's
		 * memory - this wait_table must be initialized to use this new
		 * node itself as well.
		 * To use this new node's memory, further consideration will be
		 * necessary.
		 */
4297
		zone->wait_table = vmalloc(alloc_size);
4298 4299 4300
	}
	if (!zone->wait_table)
		return -ENOMEM;
4301

4302
	for (i = 0; i < zone->wait_table_hash_nr_entries; ++i)
4303
		init_waitqueue_head(zone->wait_table + i);
4304 4305

	return 0;
4306 4307
}

4308
static __meminit void zone_pcp_init(struct zone *zone)
4309
{
4310 4311 4312 4313 4314 4315
	/*
	 * 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;
4316

4317
	if (populated_zone(zone))
4318 4319 4320
		printk(KERN_DEBUG "  %s zone: %lu pages, LIFO batch:%u\n",
			zone->name, zone->present_pages,
					 zone_batchsize(zone));
4321 4322
}

4323
int __meminit init_currently_empty_zone(struct zone *zone,
4324
					unsigned long zone_start_pfn,
D
Dave Hansen 已提交
4325 4326
					unsigned long size,
					enum memmap_context context)
4327 4328
{
	struct pglist_data *pgdat = zone->zone_pgdat;
4329 4330 4331 4332
	int ret;
	ret = zone_wait_table_init(zone, size);
	if (ret)
		return ret;
4333 4334 4335 4336
	pgdat->nr_zones = zone_idx(zone) + 1;

	zone->zone_start_pfn = zone_start_pfn;

4337 4338 4339 4340 4341 4342
	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));

4343
	zone_init_free_lists(zone);
4344 4345

	return 0;
4346 4347
}

T
Tejun Heo 已提交
4348
#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
4349 4350 4351 4352 4353 4354 4355
#ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID
/*
 * Required by SPARSEMEM. Given a PFN, return what node the PFN is on.
 * Architectures may implement their own version but if add_active_range()
 * was used and there are no special requirements, this is a convenient
 * alternative
 */
4356
int __meminit __early_pfn_to_nid(unsigned long pfn)
4357
{
4358
	unsigned long start_pfn, end_pfn;
4359
	int nid;
4360 4361 4362 4363 4364 4365 4366 4367 4368
	/*
	 * NOTE: The following SMP-unsafe globals are only used early in boot
	 * when the kernel is running single-threaded.
	 */
	static unsigned long __meminitdata last_start_pfn, last_end_pfn;
	static int __meminitdata last_nid;

	if (last_start_pfn <= pfn && pfn < last_end_pfn)
		return last_nid;
4369

4370 4371 4372 4373 4374 4375 4376 4377
	nid = memblock_search_pfn_nid(pfn, &start_pfn, &end_pfn);
	if (nid != -1) {
		last_start_pfn = start_pfn;
		last_end_pfn = end_pfn;
		last_nid = nid;
	}

	return nid;
4378 4379 4380
}
#endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */

4381 4382
int __meminit early_pfn_to_nid(unsigned long pfn)
{
4383 4384 4385 4386 4387 4388 4389
	int nid;

	nid = __early_pfn_to_nid(pfn);
	if (nid >= 0)
		return nid;
	/* just returns 0 */
	return 0;
4390 4391
}

4392 4393 4394 4395 4396 4397 4398 4399 4400 4401 4402
#ifdef CONFIG_NODES_SPAN_OTHER_NODES
bool __meminit early_pfn_in_nid(unsigned long pfn, int node)
{
	int nid;

	nid = __early_pfn_to_nid(pfn);
	if (nid >= 0 && nid != node)
		return false;
	return true;
}
#endif
4403

4404
/**
4405
 * free_bootmem_with_active_regions - Call memblock_free_early_nid for each active range
4406
 * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed.
4407
 * @max_low_pfn: The highest PFN that will be passed to memblock_free_early_nid
4408 4409 4410
 *
 * If an architecture guarantees that all ranges registered with
 * add_active_ranges() contain no holes and may be freed, this
4411 4412
 * this function may be used instead of calling memblock_free_early_nid()
 * manually.
4413
 */
4414
void __init free_bootmem_with_active_regions(int nid, unsigned long max_low_pfn)
4415
{
4416 4417
	unsigned long start_pfn, end_pfn;
	int i, this_nid;
4418

4419 4420 4421
	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);
4422

4423
		if (start_pfn < end_pfn)
4424 4425 4426
			memblock_free_early_nid(PFN_PHYS(start_pfn),
					(end_pfn - start_pfn) << PAGE_SHIFT,
					this_nid);
4427 4428 4429
	}
}

4430 4431
/**
 * sparse_memory_present_with_active_regions - Call memory_present for each active range
4432
 * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used.
4433 4434 4435
 *
 * If an architecture guarantees that all ranges registered with
 * add_active_ranges() contain no holes and may be freed, this
4436
 * function may be used instead of calling memory_present() manually.
4437 4438 4439
 */
void __init sparse_memory_present_with_active_regions(int nid)
{
4440 4441
	unsigned long start_pfn, end_pfn;
	int i, this_nid;
4442

4443 4444
	for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, &this_nid)
		memory_present(this_nid, start_pfn, end_pfn);
4445 4446 4447 4448
}

/**
 * get_pfn_range_for_nid - Return the start and end page frames for a node
4449 4450 4451
 * @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.
4452 4453 4454 4455
 *
 * It returns the start and end page frame of a node based on information
 * provided by an arch calling add_active_range(). If called for a node
 * with no available memory, a warning is printed and the start and end
4456
 * PFNs will be 0.
4457
 */
4458
void __meminit get_pfn_range_for_nid(unsigned int nid,
4459 4460
			unsigned long *start_pfn, unsigned long *end_pfn)
{
4461
	unsigned long this_start_pfn, this_end_pfn;
4462
	int i;
4463

4464 4465 4466
	*start_pfn = -1UL;
	*end_pfn = 0;

4467 4468 4469
	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);
4470 4471
	}

4472
	if (*start_pfn == -1UL)
4473 4474 4475
		*start_pfn = 0;
}

M
Mel Gorman 已提交
4476 4477 4478 4479 4480
/*
 * 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
 */
A
Adrian Bunk 已提交
4481
static void __init find_usable_zone_for_movable(void)
M
Mel Gorman 已提交
4482 4483 4484 4485 4486 4487 4488 4489 4490 4491 4492 4493 4494 4495 4496 4497 4498
{
	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
L
Lucas De Marchi 已提交
4499
 * because it is sized independent of architecture. Unlike the other zones,
M
Mel Gorman 已提交
4500 4501 4502 4503 4504 4505 4506
 * 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
 */
A
Adrian Bunk 已提交
4507
static void __meminit adjust_zone_range_for_zone_movable(int nid,
M
Mel Gorman 已提交
4508 4509 4510 4511 4512 4513 4514 4515 4516 4517 4518 4519 4520 4521 4522 4523 4524 4525 4526 4527 4528 4529 4530 4531 4532
					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 (*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;
	}
}

4533 4534 4535 4536
/*
 * 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()
 */
P
Paul Mundt 已提交
4537
static unsigned long __meminit zone_spanned_pages_in_node(int nid,
4538
					unsigned long zone_type,
4539 4540
					unsigned long node_start_pfn,
					unsigned long node_end_pfn,
4541 4542 4543 4544
					unsigned long *ignored)
{
	unsigned long zone_start_pfn, zone_end_pfn;

4545
	/* Get the start and end of the zone */
4546 4547
	zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type];
	zone_end_pfn = arch_zone_highest_possible_pfn[zone_type];
M
Mel Gorman 已提交
4548 4549 4550
	adjust_zone_range_for_zone_movable(nid, zone_type,
				node_start_pfn, node_end_pfn,
				&zone_start_pfn, &zone_end_pfn);
4551 4552 4553 4554 4555 4556 4557 4558 4559 4560 4561 4562 4563 4564 4565

	/* 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,
4566
 * then all holes in the requested range will be accounted for.
4567
 */
4568
unsigned long __meminit __absent_pages_in_range(int nid,
4569 4570 4571
				unsigned long range_start_pfn,
				unsigned long range_end_pfn)
{
4572 4573 4574
	unsigned long nr_absent = range_end_pfn - range_start_pfn;
	unsigned long start_pfn, end_pfn;
	int i;
4575

4576 4577 4578 4579
	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;
4580
	}
4581
	return nr_absent;
4582 4583 4584 4585 4586 4587 4588
}

/**
 * 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
 *
4589
 * It returns the number of pages frames in memory holes within a range.
4590 4591 4592 4593 4594 4595 4596 4597
 */
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 */
P
Paul Mundt 已提交
4598
static unsigned long __meminit zone_absent_pages_in_node(int nid,
4599
					unsigned long zone_type,
4600 4601
					unsigned long node_start_pfn,
					unsigned long node_end_pfn,
4602 4603
					unsigned long *ignored)
{
4604 4605
	unsigned long zone_low = arch_zone_lowest_possible_pfn[zone_type];
	unsigned long zone_high = arch_zone_highest_possible_pfn[zone_type];
4606 4607
	unsigned long zone_start_pfn, zone_end_pfn;

4608 4609
	zone_start_pfn = clamp(node_start_pfn, zone_low, zone_high);
	zone_end_pfn = clamp(node_end_pfn, zone_low, zone_high);
4610

M
Mel Gorman 已提交
4611 4612 4613
	adjust_zone_range_for_zone_movable(nid, zone_type,
			node_start_pfn, node_end_pfn,
			&zone_start_pfn, &zone_end_pfn);
4614
	return __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn);
4615
}
4616

T
Tejun Heo 已提交
4617
#else /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
P
Paul Mundt 已提交
4618
static inline unsigned long __meminit zone_spanned_pages_in_node(int nid,
4619
					unsigned long zone_type,
4620 4621
					unsigned long node_start_pfn,
					unsigned long node_end_pfn,
4622 4623 4624 4625 4626
					unsigned long *zones_size)
{
	return zones_size[zone_type];
}

P
Paul Mundt 已提交
4627
static inline unsigned long __meminit zone_absent_pages_in_node(int nid,
4628
						unsigned long zone_type,
4629 4630
						unsigned long node_start_pfn,
						unsigned long node_end_pfn,
4631 4632 4633 4634 4635 4636 4637
						unsigned long *zholes_size)
{
	if (!zholes_size)
		return 0;

	return zholes_size[zone_type];
}
4638

T
Tejun Heo 已提交
4639
#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
4640

4641
static void __meminit calculate_node_totalpages(struct pglist_data *pgdat,
4642 4643 4644 4645
						unsigned long node_start_pfn,
						unsigned long node_end_pfn,
						unsigned long *zones_size,
						unsigned long *zholes_size)
4646 4647 4648 4649 4650 4651
{
	unsigned long realtotalpages, totalpages = 0;
	enum zone_type i;

	for (i = 0; i < MAX_NR_ZONES; i++)
		totalpages += zone_spanned_pages_in_node(pgdat->node_id, i,
4652 4653 4654
							 node_start_pfn,
							 node_end_pfn,
							 zones_size);
4655 4656 4657 4658 4659 4660
	pgdat->node_spanned_pages = totalpages;

	realtotalpages = totalpages;
	for (i = 0; i < MAX_NR_ZONES; i++)
		realtotalpages -=
			zone_absent_pages_in_node(pgdat->node_id, i,
4661 4662
						  node_start_pfn, node_end_pfn,
						  zholes_size);
4663 4664 4665 4666 4667
	pgdat->node_present_pages = realtotalpages;
	printk(KERN_DEBUG "On node %d totalpages: %lu\n", pgdat->node_id,
							realtotalpages);
}

4668 4669 4670
#ifndef CONFIG_SPARSEMEM
/*
 * Calculate the size of the zone->blockflags rounded to an unsigned long
4671 4672
 * 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
4673 4674 4675
 * round what is now in bits to nearest long in bits, then return it in
 * bytes.
 */
4676
static unsigned long __init usemap_size(unsigned long zone_start_pfn, unsigned long zonesize)
4677 4678 4679
{
	unsigned long usemapsize;

4680
	zonesize += zone_start_pfn & (pageblock_nr_pages-1);
4681 4682
	usemapsize = roundup(zonesize, pageblock_nr_pages);
	usemapsize = usemapsize >> pageblock_order;
4683 4684 4685 4686 4687 4688 4689
	usemapsize *= NR_PAGEBLOCK_BITS;
	usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long));

	return usemapsize / 8;
}

static void __init setup_usemap(struct pglist_data *pgdat,
4690 4691 4692
				struct zone *zone,
				unsigned long zone_start_pfn,
				unsigned long zonesize)
4693
{
4694
	unsigned long usemapsize = usemap_size(zone_start_pfn, zonesize);
4695
	zone->pageblock_flags = NULL;
4696
	if (usemapsize)
4697 4698 4699
		zone->pageblock_flags =
			memblock_virt_alloc_node_nopanic(usemapsize,
							 pgdat->node_id);
4700 4701
}
#else
4702 4703
static inline void setup_usemap(struct pglist_data *pgdat, struct zone *zone,
				unsigned long zone_start_pfn, unsigned long zonesize) {}
4704 4705
#endif /* CONFIG_SPARSEMEM */

4706
#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE
4707

4708
/* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */
4709
void __paginginit set_pageblock_order(void)
4710
{
4711 4712
	unsigned int order;

4713 4714 4715 4716
	/* Check that pageblock_nr_pages has not already been setup */
	if (pageblock_order)
		return;

4717 4718 4719 4720 4721
	if (HPAGE_SHIFT > PAGE_SHIFT)
		order = HUGETLB_PAGE_ORDER;
	else
		order = MAX_ORDER - 1;

4722 4723
	/*
	 * Assume the largest contiguous order of interest is a huge page.
4724 4725
	 * This value may be variable depending on boot parameters on IA64 and
	 * powerpc.
4726 4727 4728 4729 4730
	 */
	pageblock_order = order;
}
#else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */

4731 4732
/*
 * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order()
4733 4734 4735
 * 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
4736
 */
4737
void __paginginit set_pageblock_order(void)
4738 4739
{
}
4740 4741 4742

#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */

4743 4744 4745 4746 4747 4748 4749 4750 4751 4752 4753 4754 4755 4756 4757 4758 4759 4760 4761 4762
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;
}

L
Linus Torvalds 已提交
4763 4764 4765 4766 4767
/*
 * Set up the zone data structures:
 *   - mark all pages reserved
 *   - mark all memory queues empty
 *   - clear the memory bitmaps
4768 4769
 *
 * NOTE: pgdat should get zeroed by caller.
L
Linus Torvalds 已提交
4770
 */
4771
static void __paginginit free_area_init_core(struct pglist_data *pgdat,
4772
		unsigned long node_start_pfn, unsigned long node_end_pfn,
L
Linus Torvalds 已提交
4773 4774
		unsigned long *zones_size, unsigned long *zholes_size)
{
4775
	enum zone_type j;
4776
	int nid = pgdat->node_id;
L
Linus Torvalds 已提交
4777
	unsigned long zone_start_pfn = pgdat->node_start_pfn;
4778
	int ret;
L
Linus Torvalds 已提交
4779

4780
	pgdat_resize_init(pgdat);
4781 4782 4783 4784 4785
#ifdef CONFIG_NUMA_BALANCING
	spin_lock_init(&pgdat->numabalancing_migrate_lock);
	pgdat->numabalancing_migrate_nr_pages = 0;
	pgdat->numabalancing_migrate_next_window = jiffies;
#endif
L
Linus Torvalds 已提交
4786
	init_waitqueue_head(&pgdat->kswapd_wait);
4787
	init_waitqueue_head(&pgdat->pfmemalloc_wait);
4788
	pgdat_page_cgroup_init(pgdat);
4789

L
Linus Torvalds 已提交
4790 4791
	for (j = 0; j < MAX_NR_ZONES; j++) {
		struct zone *zone = pgdat->node_zones + j;
4792
		unsigned long size, realsize, freesize, memmap_pages;
L
Linus Torvalds 已提交
4793

4794 4795
		size = zone_spanned_pages_in_node(nid, j, node_start_pfn,
						  node_end_pfn, zones_size);
4796
		realsize = freesize = size - zone_absent_pages_in_node(nid, j,
4797 4798
								node_start_pfn,
								node_end_pfn,
4799
								zholes_size);
L
Linus Torvalds 已提交
4800

4801
		/*
4802
		 * Adjust freesize so that it accounts for how much memory
4803 4804 4805
		 * is used by this zone for memmap. This affects the watermark
		 * and per-cpu initialisations
		 */
4806
		memmap_pages = calc_memmap_size(size, realsize);
4807 4808
		if (freesize >= memmap_pages) {
			freesize -= memmap_pages;
4809 4810 4811 4812
			if (memmap_pages)
				printk(KERN_DEBUG
				       "  %s zone: %lu pages used for memmap\n",
				       zone_names[j], memmap_pages);
4813 4814
		} else
			printk(KERN_WARNING
4815 4816
				"  %s zone: %lu pages exceeds freesize %lu\n",
				zone_names[j], memmap_pages, freesize);
4817

4818
		/* Account for reserved pages */
4819 4820
		if (j == 0 && freesize > dma_reserve) {
			freesize -= dma_reserve;
Y
Yinghai Lu 已提交
4821
			printk(KERN_DEBUG "  %s zone: %lu pages reserved\n",
4822
					zone_names[0], dma_reserve);
4823 4824
		}

4825
		if (!is_highmem_idx(j))
4826
			nr_kernel_pages += freesize;
4827 4828 4829
		/* Charge for highmem memmap if there are enough kernel pages */
		else if (nr_kernel_pages > memmap_pages * 2)
			nr_kernel_pages -= memmap_pages;
4830
		nr_all_pages += freesize;
L
Linus Torvalds 已提交
4831 4832

		zone->spanned_pages = size;
4833
		zone->present_pages = realsize;
4834 4835 4836 4837 4838 4839
		/*
		 * 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;
4840
#ifdef CONFIG_NUMA
4841
		zone->node = nid;
4842
		zone->min_unmapped_pages = (freesize*sysctl_min_unmapped_ratio)
4843
						/ 100;
4844
		zone->min_slab_pages = (freesize * sysctl_min_slab_ratio) / 100;
4845
#endif
L
Linus Torvalds 已提交
4846 4847 4848
		zone->name = zone_names[j];
		spin_lock_init(&zone->lock);
		spin_lock_init(&zone->lru_lock);
4849
		zone_seqlock_init(zone);
L
Linus Torvalds 已提交
4850
		zone->zone_pgdat = pgdat;
4851
		zone_pcp_init(zone);
4852 4853 4854 4855

		/* For bootup, initialized properly in watermark setup */
		mod_zone_page_state(zone, NR_ALLOC_BATCH, zone->managed_pages);

4856
		lruvec_init(&zone->lruvec);
L
Linus Torvalds 已提交
4857 4858 4859
		if (!size)
			continue;

4860
		set_pageblock_order();
4861
		setup_usemap(pgdat, zone, zone_start_pfn, size);
D
Dave Hansen 已提交
4862 4863
		ret = init_currently_empty_zone(zone, zone_start_pfn,
						size, MEMMAP_EARLY);
4864
		BUG_ON(ret);
4865
		memmap_init(size, nid, j, zone_start_pfn);
L
Linus Torvalds 已提交
4866 4867 4868 4869
		zone_start_pfn += size;
	}
}

S
Sam Ravnborg 已提交
4870
static void __init_refok alloc_node_mem_map(struct pglist_data *pgdat)
L
Linus Torvalds 已提交
4871 4872 4873 4874 4875
{
	/* Skip empty nodes */
	if (!pgdat->node_spanned_pages)
		return;

A
Andy Whitcroft 已提交
4876
#ifdef CONFIG_FLAT_NODE_MEM_MAP
L
Linus Torvalds 已提交
4877 4878
	/* ia64 gets its own node_mem_map, before this, without bootmem */
	if (!pgdat->node_mem_map) {
4879
		unsigned long size, start, end;
A
Andy Whitcroft 已提交
4880 4881
		struct page *map;

4882 4883 4884 4885 4886 4887
		/*
		 * 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.
		 */
		start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1);
4888
		end = pgdat_end_pfn(pgdat);
4889 4890
		end = ALIGN(end, MAX_ORDER_NR_PAGES);
		size =  (end - start) * sizeof(struct page);
4891 4892
		map = alloc_remap(pgdat->node_id, size);
		if (!map)
4893 4894
			map = memblock_virt_alloc_node_nopanic(size,
							       pgdat->node_id);
4895
		pgdat->node_mem_map = map + (pgdat->node_start_pfn - start);
L
Linus Torvalds 已提交
4896
	}
4897
#ifndef CONFIG_NEED_MULTIPLE_NODES
L
Linus Torvalds 已提交
4898 4899 4900
	/*
	 * With no DISCONTIG, the global mem_map is just set as node 0's
	 */
4901
	if (pgdat == NODE_DATA(0)) {
L
Linus Torvalds 已提交
4902
		mem_map = NODE_DATA(0)->node_mem_map;
T
Tejun Heo 已提交
4903
#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
4904
		if (page_to_pfn(mem_map) != pgdat->node_start_pfn)
4905
			mem_map -= (pgdat->node_start_pfn - ARCH_PFN_OFFSET);
T
Tejun Heo 已提交
4906
#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
4907
	}
L
Linus Torvalds 已提交
4908
#endif
A
Andy Whitcroft 已提交
4909
#endif /* CONFIG_FLAT_NODE_MEM_MAP */
L
Linus Torvalds 已提交
4910 4911
}

4912 4913
void __paginginit free_area_init_node(int nid, unsigned long *zones_size,
		unsigned long node_start_pfn, unsigned long *zholes_size)
L
Linus Torvalds 已提交
4914
{
4915
	pg_data_t *pgdat = NODE_DATA(nid);
4916 4917
	unsigned long start_pfn = 0;
	unsigned long end_pfn = 0;
4918

4919
	/* pg_data_t should be reset to zero when it's allocated */
4920
	WARN_ON(pgdat->nr_zones || pgdat->classzone_idx);
4921

L
Linus Torvalds 已提交
4922 4923
	pgdat->node_id = nid;
	pgdat->node_start_pfn = node_start_pfn;
4924 4925
	if (node_state(nid, N_MEMORY))
		init_zone_allows_reclaim(nid);
4926 4927 4928 4929 4930
#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
	get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
#endif
	calculate_node_totalpages(pgdat, start_pfn, end_pfn,
				  zones_size, zholes_size);
L
Linus Torvalds 已提交
4931 4932

	alloc_node_mem_map(pgdat);
4933 4934 4935 4936 4937
#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
L
Linus Torvalds 已提交
4938

4939 4940
	free_area_init_core(pgdat, start_pfn, end_pfn,
			    zones_size, zholes_size);
L
Linus Torvalds 已提交
4941 4942
}

T
Tejun Heo 已提交
4943
#ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
M
Miklos Szeredi 已提交
4944 4945 4946 4947 4948

#if MAX_NUMNODES > 1
/*
 * Figure out the number of possible node ids.
 */
4949
void __init setup_nr_node_ids(void)
M
Miklos Szeredi 已提交
4950 4951 4952 4953 4954 4955 4956 4957 4958 4959
{
	unsigned int node;
	unsigned int highest = 0;

	for_each_node_mask(node, node_possible_map)
		highest = node;
	nr_node_ids = highest + 1;
}
#endif

4960 4961 4962 4963 4964 4965 4966 4967 4968 4969 4970 4971 4972 4973 4974 4975 4976 4977 4978 4979 4980 4981
/**
 * 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;
4982
	unsigned long start, end, mask;
4983
	int last_nid = -1;
4984
	int i, nid;
4985

4986
	for_each_mem_pfn_range(i, MAX_NUMNODES, &start, &end, &nid) {
4987 4988 4989 4990 4991 4992 4993 4994 4995 4996 4997 4998 4999 5000 5001 5002 5003 5004 5005 5006 5007 5008 5009
		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;
}

5010
/* Find the lowest pfn for a node */
A
Adrian Bunk 已提交
5011
static unsigned long __init find_min_pfn_for_node(int nid)
5012
{
5013
	unsigned long min_pfn = ULONG_MAX;
5014 5015
	unsigned long start_pfn;
	int i;
5016

5017 5018
	for_each_mem_pfn_range(i, nid, &start_pfn, NULL, NULL)
		min_pfn = min(min_pfn, start_pfn);
5019

5020 5021
	if (min_pfn == ULONG_MAX) {
		printk(KERN_WARNING
5022
			"Could not find start_pfn for node %d\n", nid);
5023 5024 5025 5026
		return 0;
	}

	return min_pfn;
5027 5028 5029 5030 5031 5032
}

/**
 * find_min_pfn_with_active_regions - Find the minimum PFN registered
 *
 * It returns the minimum PFN based on information provided via
5033
 * add_active_range().
5034 5035 5036 5037 5038 5039
 */
unsigned long __init find_min_pfn_with_active_regions(void)
{
	return find_min_pfn_for_node(MAX_NUMNODES);
}

5040 5041 5042
/*
 * early_calculate_totalpages()
 * Sum pages in active regions for movable zone.
5043
 * Populate N_MEMORY for calculating usable_nodes.
5044
 */
A
Adrian Bunk 已提交
5045
static unsigned long __init early_calculate_totalpages(void)
5046 5047
{
	unsigned long totalpages = 0;
5048 5049 5050 5051 5052
	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;
5053

5054 5055
		totalpages += pages;
		if (pages)
5056
			node_set_state(nid, N_MEMORY);
5057
	}
5058
	return totalpages;
5059 5060
}

M
Mel Gorman 已提交
5061 5062 5063 5064 5065 5066
/*
 * 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
 */
5067
static void __init find_zone_movable_pfns_for_nodes(void)
M
Mel Gorman 已提交
5068 5069 5070 5071
{
	int i, nid;
	unsigned long usable_startpfn;
	unsigned long kernelcore_node, kernelcore_remaining;
5072
	/* save the state before borrow the nodemask */
5073
	nodemask_t saved_node_state = node_states[N_MEMORY];
5074
	unsigned long totalpages = early_calculate_totalpages();
5075
	int usable_nodes = nodes_weight(node_states[N_MEMORY]);
E
Emil Medve 已提交
5076
	struct memblock_region *r;
5077 5078 5079 5080 5081 5082 5083 5084 5085

	/* 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()) {
E
Emil Medve 已提交
5086 5087
		for_each_memblock(memory, r) {
			if (!memblock_is_hotpluggable(r))
5088 5089
				continue;

E
Emil Medve 已提交
5090
			nid = r->nid;
5091

E
Emil Medve 已提交
5092
			usable_startpfn = PFN_DOWN(r->base);
5093 5094 5095 5096 5097 5098 5099
			zone_movable_pfn[nid] = zone_movable_pfn[nid] ?
				min(usable_startpfn, zone_movable_pfn[nid]) :
				usable_startpfn;
		}

		goto out2;
	}
M
Mel Gorman 已提交
5100

5101
	/*
5102
	 * If movablecore=nn[KMG] was specified, calculate what size of
5103 5104 5105 5106 5107 5108 5109 5110 5111 5112 5113 5114 5115 5116 5117 5118 5119 5120 5121 5122
	 * 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);
		corepages = totalpages - required_movablecore;

		required_kernelcore = max(required_kernelcore, corepages);
	}

5123 5124
	/* If kernelcore was not specified, there is no ZONE_MOVABLE */
	if (!required_kernelcore)
5125
		goto out;
M
Mel Gorman 已提交
5126 5127 5128 5129 5130 5131 5132

	/* 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;
5133
	for_each_node_state(nid, N_MEMORY) {
5134 5135
		unsigned long start_pfn, end_pfn;

M
Mel Gorman 已提交
5136 5137 5138 5139 5140 5141 5142 5143 5144 5145 5146 5147 5148 5149 5150 5151
		/*
		 * 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 */
5152
		for_each_mem_pfn_range(i, nid, &start_pfn, &end_pfn, NULL) {
M
Mel Gorman 已提交
5153 5154
			unsigned long size_pages;

5155
			start_pfn = max(start_pfn, zone_movable_pfn[nid]);
M
Mel Gorman 已提交
5156 5157 5158 5159 5160 5161 5162 5163 5164 5165 5166 5167 5168 5169 5170 5171 5172 5173 5174 5175 5176 5177 5178 5179 5180 5181 5182 5183 5184 5185 5186 5187 5188 5189 5190 5191 5192 5193 5194 5195 5196 5197
			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
5198
			 * satisfied
M
Mel Gorman 已提交
5199 5200 5201 5202 5203 5204 5205 5206 5207 5208 5209 5210 5211
			 */
			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
5212
	 * satisfied
M
Mel Gorman 已提交
5213 5214 5215 5216 5217
	 */
	usable_nodes--;
	if (usable_nodes && required_kernelcore > usable_nodes)
		goto restart;

5218
out2:
M
Mel Gorman 已提交
5219 5220 5221 5222
	/* 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);
5223

5224
out:
5225
	/* restore the node_state */
5226
	node_states[N_MEMORY] = saved_node_state;
M
Mel Gorman 已提交
5227 5228
}

5229 5230
/* Any regular or high memory on that node ? */
static void check_for_memory(pg_data_t *pgdat, int nid)
5231 5232 5233
{
	enum zone_type zone_type;

5234 5235 5236 5237
	if (N_MEMORY == N_NORMAL_MEMORY)
		return;

	for (zone_type = 0; zone_type <= ZONE_MOVABLE - 1; zone_type++) {
5238
		struct zone *zone = &pgdat->node_zones[zone_type];
5239
		if (populated_zone(zone)) {
5240 5241 5242 5243
			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);
5244 5245
			break;
		}
5246 5247 5248
	}
}

5249 5250
/**
 * free_area_init_nodes - Initialise all pg_data_t and zone data
5251
 * @max_zone_pfn: an array of max PFNs for each zone
5252 5253 5254 5255 5256 5257 5258 5259 5260 5261 5262 5263
 *
 * This will call free_area_init_node() for each active node in the system.
 * Using the page ranges provided by add_active_range(), 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)
{
5264 5265
	unsigned long start_pfn, end_pfn;
	int i, nid;
5266

5267 5268 5269 5270 5271 5272 5273 5274
	/* 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));
	arch_zone_lowest_possible_pfn[0] = find_min_pfn_with_active_regions();
	arch_zone_highest_possible_pfn[0] = max_zone_pfn[0];
	for (i = 1; i < MAX_NR_ZONES; i++) {
M
Mel Gorman 已提交
5275 5276
		if (i == ZONE_MOVABLE)
			continue;
5277 5278 5279 5280 5281
		arch_zone_lowest_possible_pfn[i] =
			arch_zone_highest_possible_pfn[i-1];
		arch_zone_highest_possible_pfn[i] =
			max(max_zone_pfn[i], arch_zone_lowest_possible_pfn[i]);
	}
M
Mel Gorman 已提交
5282 5283 5284 5285 5286
	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));
5287
	find_zone_movable_pfns_for_nodes();
5288 5289

	/* Print out the zone ranges */
5290
	printk("Zone ranges:\n");
M
Mel Gorman 已提交
5291 5292 5293
	for (i = 0; i < MAX_NR_ZONES; i++) {
		if (i == ZONE_MOVABLE)
			continue;
5294
		printk(KERN_CONT "  %-8s ", zone_names[i]);
5295 5296
		if (arch_zone_lowest_possible_pfn[i] ==
				arch_zone_highest_possible_pfn[i])
5297
			printk(KERN_CONT "empty\n");
5298
		else
5299 5300 5301 5302
			printk(KERN_CONT "[mem %0#10lx-%0#10lx]\n",
				arch_zone_lowest_possible_pfn[i] << PAGE_SHIFT,
				(arch_zone_highest_possible_pfn[i]
					<< PAGE_SHIFT) - 1);
M
Mel Gorman 已提交
5303 5304 5305
	}

	/* Print out the PFNs ZONE_MOVABLE begins at in each node */
5306
	printk("Movable zone start for each node\n");
M
Mel Gorman 已提交
5307 5308
	for (i = 0; i < MAX_NUMNODES; i++) {
		if (zone_movable_pfn[i])
5309 5310
			printk("  Node %d: %#010lx\n", i,
			       zone_movable_pfn[i] << PAGE_SHIFT);
M
Mel Gorman 已提交
5311
	}
5312

5313
	/* Print out the early node map */
5314
	printk("Early memory node ranges\n");
5315
	for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid)
5316 5317
		printk("  node %3d: [mem %#010lx-%#010lx]\n", nid,
		       start_pfn << PAGE_SHIFT, (end_pfn << PAGE_SHIFT) - 1);
5318 5319

	/* Initialise every node */
5320
	mminit_verify_pageflags_layout();
5321
	setup_nr_node_ids();
5322 5323
	for_each_online_node(nid) {
		pg_data_t *pgdat = NODE_DATA(nid);
5324
		free_area_init_node(nid, NULL,
5325
				find_min_pfn_for_node(nid), NULL);
5326 5327 5328

		/* Any memory on that node */
		if (pgdat->node_present_pages)
5329 5330
			node_set_state(nid, N_MEMORY);
		check_for_memory(pgdat, nid);
5331 5332
	}
}
M
Mel Gorman 已提交
5333

5334
static int __init cmdline_parse_core(char *p, unsigned long *core)
M
Mel Gorman 已提交
5335 5336 5337 5338 5339 5340
{
	unsigned long long coremem;
	if (!p)
		return -EINVAL;

	coremem = memparse(p, &p);
5341
	*core = coremem >> PAGE_SHIFT;
M
Mel Gorman 已提交
5342

5343
	/* Paranoid check that UL is enough for the coremem value */
M
Mel Gorman 已提交
5344 5345 5346 5347
	WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX);

	return 0;
}
M
Mel Gorman 已提交
5348

5349 5350 5351 5352 5353 5354 5355 5356 5357 5358 5359 5360 5361 5362 5363 5364 5365 5366
/*
 * 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)
{
	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);
}

M
Mel Gorman 已提交
5367
early_param("kernelcore", cmdline_parse_kernelcore);
5368
early_param("movablecore", cmdline_parse_movablecore);
M
Mel Gorman 已提交
5369

T
Tejun Heo 已提交
5370
#endif /* CONFIG_HAVE_MEMBLOCK_NODE_MAP */
5371

5372 5373 5374 5375 5376
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;
5377 5378 5379 5380
#ifdef CONFIG_HIGHMEM
	if (PageHighMem(page))
		totalhigh_pages += count;
#endif
5381 5382
	spin_unlock(&managed_page_count_lock);
}
5383
EXPORT_SYMBOL(adjust_managed_page_count);
5384

5385
unsigned long free_reserved_area(void *start, void *end, int poison, char *s)
5386
{
5387 5388
	void *pos;
	unsigned long pages = 0;
5389

5390 5391 5392
	start = (void *)PAGE_ALIGN((unsigned long)start);
	end = (void *)((unsigned long)end & PAGE_MASK);
	for (pos = start; pos < end; pos += PAGE_SIZE, pages++) {
5393
		if ((unsigned int)poison <= 0xFF)
5394 5395
			memset(pos, poison, PAGE_SIZE);
		free_reserved_page(virt_to_page(pos));
5396 5397 5398
	}

	if (pages && s)
5399
		pr_info("Freeing %s memory: %ldK (%p - %p)\n",
5400 5401 5402 5403
			s, pages << (PAGE_SHIFT - 10), start, end);

	return pages;
}
5404
EXPORT_SYMBOL(free_reserved_area);
5405

5406 5407 5408 5409 5410
#ifdef	CONFIG_HIGHMEM
void free_highmem_page(struct page *page)
{
	__free_reserved_page(page);
	totalram_pages++;
5411
	page_zone(page)->managed_pages++;
5412 5413 5414 5415
	totalhigh_pages++;
}
#endif

5416 5417 5418 5419 5420 5421 5422 5423 5424 5425 5426 5427 5428 5429 5430 5431 5432 5433 5434 5435 5436 5437

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) \
5438 5439 5440 5441
	do { \
		if (start <= pos && pos < end && size > adj) \
			size -= adj; \
	} while (0)
5442 5443 5444 5445 5446 5447 5448 5449 5450 5451 5452 5453 5454 5455 5456 5457 5458 5459 5460 5461 5462 5463 5464 5465 5466 5467 5468

	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

	printk("Memory: %luK/%luK available "
	       "(%luK kernel code, %luK rwdata, %luK rodata, "
	       "%luK init, %luK bss, %luK 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) << (PAGE_SHIFT-10),
#ifdef	CONFIG_HIGHMEM
	       totalhigh_pages << (PAGE_SHIFT-10),
#endif
	       str ? ", " : "", str ? str : "");
}

5469
/**
5470 5471
 * set_dma_reserve - set the specified number of pages reserved in the first zone
 * @new_dma_reserve: The number of pages to mark reserved
5472 5473 5474 5475
 *
 * The per-cpu batchsize and zone watermarks are determined by present_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
5476 5477 5478
 * 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.
5479 5480 5481 5482 5483 5484
 */
void __init set_dma_reserve(unsigned long new_dma_reserve)
{
	dma_reserve = new_dma_reserve;
}

L
Linus Torvalds 已提交
5485 5486
void __init free_area_init(unsigned long *zones_size)
{
5487
	free_area_init_node(0, zones_size,
L
Linus Torvalds 已提交
5488 5489 5490 5491 5492 5493 5494 5495
			__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;

5496
	if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) {
5497
		lru_add_drain_cpu(cpu);
5498 5499 5500 5501 5502 5503 5504 5505
		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.
		 */
5506
		vm_events_fold_cpu(cpu);
5507 5508 5509 5510 5511 5512 5513 5514

		/*
		 * 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.
		 */
5515
		cpu_vm_stats_fold(cpu);
L
Linus Torvalds 已提交
5516 5517 5518 5519 5520 5521 5522 5523 5524
	}
	return NOTIFY_OK;
}

void __init page_alloc_init(void)
{
	hotcpu_notifier(page_alloc_cpu_notify, 0);
}

5525 5526 5527 5528 5529 5530 5531 5532
/*
 * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio
 *	or min_free_kbytes changes.
 */
static void calculate_totalreserve_pages(void)
{
	struct pglist_data *pgdat;
	unsigned long reserve_pages = 0;
5533
	enum zone_type i, j;
5534 5535 5536 5537 5538 5539 5540 5541 5542 5543 5544 5545

	for_each_online_pgdat(pgdat) {
		for (i = 0; i < MAX_NR_ZONES; i++) {
			struct zone *zone = pgdat->node_zones + i;
			unsigned 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];
			}

5546 5547
			/* we treat the high watermark as reserved pages. */
			max += high_wmark_pages(zone);
5548

5549 5550
			if (max > zone->managed_pages)
				max = zone->managed_pages;
5551
			reserve_pages += max;
5552 5553 5554 5555 5556 5557 5558 5559 5560 5561
			/*
			 * Lowmem reserves are not available to
			 * GFP_HIGHUSER page cache allocations and
			 * kswapd tries to balance zones to their high
			 * watermark.  As a result, neither should be
			 * regarded as dirtyable memory, to prevent a
			 * situation where reclaim has to clean pages
			 * in order to balance the zones.
			 */
			zone->dirty_balance_reserve = max;
5562 5563
		}
	}
5564
	dirty_balance_reserve = reserve_pages;
5565 5566 5567
	totalreserve_pages = reserve_pages;
}

L
Linus Torvalds 已提交
5568 5569 5570 5571 5572 5573 5574 5575 5576
/*
 * setup_per_zone_lowmem_reserve - called whenever
 *	sysctl_lower_zone_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;
5577
	enum zone_type j, idx;
L
Linus Torvalds 已提交
5578

5579
	for_each_online_pgdat(pgdat) {
L
Linus Torvalds 已提交
5580 5581
		for (j = 0; j < MAX_NR_ZONES; j++) {
			struct zone *zone = pgdat->node_zones + j;
5582
			unsigned long managed_pages = zone->managed_pages;
L
Linus Torvalds 已提交
5583 5584 5585

			zone->lowmem_reserve[j] = 0;

5586 5587
			idx = j;
			while (idx) {
L
Linus Torvalds 已提交
5588 5589
				struct zone *lower_zone;

5590 5591
				idx--;

L
Linus Torvalds 已提交
5592 5593 5594 5595
				if (sysctl_lowmem_reserve_ratio[idx] < 1)
					sysctl_lowmem_reserve_ratio[idx] = 1;

				lower_zone = pgdat->node_zones + idx;
5596
				lower_zone->lowmem_reserve[j] = managed_pages /
L
Linus Torvalds 已提交
5597
					sysctl_lowmem_reserve_ratio[idx];
5598
				managed_pages += lower_zone->managed_pages;
L
Linus Torvalds 已提交
5599 5600 5601
			}
		}
	}
5602 5603 5604

	/* update totalreserve_pages */
	calculate_totalreserve_pages();
L
Linus Torvalds 已提交
5605 5606
}

5607
static void __setup_per_zone_wmarks(void)
L
Linus Torvalds 已提交
5608 5609 5610 5611 5612 5613 5614 5615 5616
{
	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))
5617
			lowmem_pages += zone->managed_pages;
L
Linus Torvalds 已提交
5618 5619 5620
	}

	for_each_zone(zone) {
5621 5622
		u64 tmp;

5623
		spin_lock_irqsave(&zone->lock, flags);
5624
		tmp = (u64)pages_min * zone->managed_pages;
5625
		do_div(tmp, lowmem_pages);
L
Linus Torvalds 已提交
5626 5627
		if (is_highmem(zone)) {
			/*
N
Nick Piggin 已提交
5628 5629 5630 5631
			 * __GFP_HIGH and PF_MEMALLOC allocations usually don't
			 * need highmem pages, so cap pages_min to a small
			 * value here.
			 *
5632
			 * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN)
N
Nick Piggin 已提交
5633 5634
			 * deltas controls asynch page reclaim, and so should
			 * not be capped for highmem.
L
Linus Torvalds 已提交
5635
			 */
5636
			unsigned long min_pages;
L
Linus Torvalds 已提交
5637

5638
			min_pages = zone->managed_pages / 1024;
5639
			min_pages = clamp(min_pages, SWAP_CLUSTER_MAX, 128UL);
5640
			zone->watermark[WMARK_MIN] = min_pages;
L
Linus Torvalds 已提交
5641
		} else {
N
Nick Piggin 已提交
5642 5643
			/*
			 * If it's a lowmem zone, reserve a number of pages
L
Linus Torvalds 已提交
5644 5645
			 * proportionate to the zone's size.
			 */
5646
			zone->watermark[WMARK_MIN] = tmp;
L
Linus Torvalds 已提交
5647 5648
		}

5649 5650
		zone->watermark[WMARK_LOW]  = min_wmark_pages(zone) + (tmp >> 2);
		zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + (tmp >> 1);
5651

5652 5653 5654 5655 5656
		__mod_zone_page_state(zone, NR_ALLOC_BATCH,
				      high_wmark_pages(zone) -
				      low_wmark_pages(zone) -
				      zone_page_state(zone, NR_ALLOC_BATCH));

5657
		setup_zone_migrate_reserve(zone);
5658
		spin_unlock_irqrestore(&zone->lock, flags);
L
Linus Torvalds 已提交
5659
	}
5660 5661 5662

	/* update totalreserve_pages */
	calculate_totalreserve_pages();
L
Linus Torvalds 已提交
5663 5664
}

5665 5666 5667 5668 5669 5670 5671 5672 5673 5674 5675 5676 5677 5678
/**
 * 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);
}

5679
/*
5680 5681 5682 5683 5684 5685 5686 5687 5688 5689 5690 5691 5692 5693 5694 5695 5696 5697 5698 5699
 * The inactive anon list should be small enough that the VM never has to
 * do too much work, but large enough that each inactive page has a chance
 * to be referenced again before it is swapped out.
 *
 * The inactive_anon ratio is the target ratio of ACTIVE_ANON to
 * INACTIVE_ANON pages on this zone's LRU, maintained by the
 * pageout code. A zone->inactive_ratio of 3 means 3:1 or 25% of
 * the anonymous pages are kept on the inactive list.
 *
 * total     target    max
 * memory    ratio     inactive anon
 * -------------------------------------
 *   10MB       1         5MB
 *  100MB       1        50MB
 *    1GB       3       250MB
 *   10GB      10       0.9GB
 *  100GB      31         3GB
 *    1TB     101        10GB
 *   10TB     320        32GB
 */
5700
static void __meminit calculate_zone_inactive_ratio(struct zone *zone)
5701
{
5702
	unsigned int gb, ratio;
5703

5704
	/* Zone size in gigabytes */
5705
	gb = zone->managed_pages >> (30 - PAGE_SHIFT);
5706
	if (gb)
5707
		ratio = int_sqrt(10 * gb);
5708 5709
	else
		ratio = 1;
5710

5711 5712
	zone->inactive_ratio = ratio;
}
5713

5714
static void __meminit setup_per_zone_inactive_ratio(void)
5715 5716 5717 5718 5719
{
	struct zone *zone;

	for_each_zone(zone)
		calculate_zone_inactive_ratio(zone);
5720 5721
}

L
Linus Torvalds 已提交
5722 5723 5724 5725 5726 5727 5728
/*
 * 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
 *
5729
 *	min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy:
L
Linus Torvalds 已提交
5730 5731 5732 5733 5734 5735 5736 5737 5738 5739 5740 5741 5742 5743 5744 5745
 *	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
 */
5746
int __meminit init_per_zone_wmark_min(void)
L
Linus Torvalds 已提交
5747 5748
{
	unsigned long lowmem_kbytes;
5749
	int new_min_free_kbytes;
L
Linus Torvalds 已提交
5750 5751

	lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10);
5752 5753 5754 5755 5756 5757 5758 5759 5760 5761 5762 5763
	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);
	}
5764
	setup_per_zone_wmarks();
5765
	refresh_zone_stat_thresholds();
L
Linus Torvalds 已提交
5766
	setup_per_zone_lowmem_reserve();
5767
	setup_per_zone_inactive_ratio();
L
Linus Torvalds 已提交
5768 5769
	return 0;
}
5770
module_init(init_per_zone_wmark_min)
L
Linus Torvalds 已提交
5771 5772

/*
5773
 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
L
Linus Torvalds 已提交
5774 5775 5776
 *	that we can call two helper functions whenever min_free_kbytes
 *	changes.
 */
5777
int min_free_kbytes_sysctl_handler(ctl_table *table, int write,
5778
	void __user *buffer, size_t *length, loff_t *ppos)
L
Linus Torvalds 已提交
5779
{
5780 5781 5782 5783 5784 5785
	int rc;

	rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
	if (rc)
		return rc;

5786 5787
	if (write) {
		user_min_free_kbytes = min_free_kbytes;
5788
		setup_per_zone_wmarks();
5789
	}
L
Linus Torvalds 已提交
5790 5791 5792
	return 0;
}

5793 5794
#ifdef CONFIG_NUMA
int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table *table, int write,
5795
	void __user *buffer, size_t *length, loff_t *ppos)
5796 5797 5798 5799
{
	struct zone *zone;
	int rc;

5800
	rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
5801 5802 5803 5804
	if (rc)
		return rc;

	for_each_zone(zone)
5805
		zone->min_unmapped_pages = (zone->managed_pages *
5806 5807 5808
				sysctl_min_unmapped_ratio) / 100;
	return 0;
}
5809 5810

int sysctl_min_slab_ratio_sysctl_handler(ctl_table *table, int write,
5811
	void __user *buffer, size_t *length, loff_t *ppos)
5812 5813 5814 5815
{
	struct zone *zone;
	int rc;

5816
	rc = proc_dointvec_minmax(table, write, buffer, length, ppos);
5817 5818 5819 5820
	if (rc)
		return rc;

	for_each_zone(zone)
5821
		zone->min_slab_pages = (zone->managed_pages *
5822 5823 5824
				sysctl_min_slab_ratio) / 100;
	return 0;
}
5825 5826
#endif

L
Linus Torvalds 已提交
5827 5828 5829 5830 5831 5832
/*
 * 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
5833
 * minimum watermarks. The lowmem reserve ratio can only make sense
L
Linus Torvalds 已提交
5834 5835 5836
 * if in function of the boot time zone sizes.
 */
int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write,
5837
	void __user *buffer, size_t *length, loff_t *ppos)
L
Linus Torvalds 已提交
5838
{
5839
	proc_dointvec_minmax(table, write, buffer, length, ppos);
L
Linus Torvalds 已提交
5840 5841 5842 5843
	setup_per_zone_lowmem_reserve();
	return 0;
}

5844 5845
/*
 * percpu_pagelist_fraction - changes the pcp->high for each zone on each
5846 5847
 * 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.
5848 5849
 */
int percpu_pagelist_fraction_sysctl_handler(ctl_table *table, int write,
5850
	void __user *buffer, size_t *length, loff_t *ppos)
5851 5852 5853 5854 5855
{
	struct zone *zone;
	unsigned int cpu;
	int ret;

5856
	ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
5857
	if (!write || (ret < 0))
5858
		return ret;
5859 5860

	mutex_lock(&pcp_batch_high_lock);
5861
	for_each_populated_zone(zone) {
5862 5863 5864
		unsigned long  high;
		high = zone->managed_pages / percpu_pagelist_fraction;
		for_each_possible_cpu(cpu)
5865 5866
			pageset_set_high(per_cpu_ptr(zone->pageset, cpu),
					 high);
5867
	}
5868
	mutex_unlock(&pcp_batch_high_lock);
5869 5870 5871
	return 0;
}

5872
int hashdist = HASHDIST_DEFAULT;
L
Linus Torvalds 已提交
5873 5874 5875 5876 5877 5878 5879 5880 5881 5882 5883 5884 5885 5886 5887 5888 5889 5890 5891 5892 5893 5894 5895 5896 5897

#ifdef CONFIG_NUMA
static int __init set_hashdist(char *str)
{
	if (!str)
		return 0;
	hashdist = simple_strtoul(str, &str, 0);
	return 1;
}
__setup("hashdist=", set_hashdist);
#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,
5898 5899
				     unsigned long low_limit,
				     unsigned long high_limit)
L
Linus Torvalds 已提交
5900
{
5901
	unsigned long long max = high_limit;
L
Linus Torvalds 已提交
5902 5903 5904 5905 5906 5907
	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 */
A
Andrew Morton 已提交
5908
		numentries = nr_kernel_pages;
5909 5910 5911 5912

		/* It isn't necessary when PAGE_SIZE >= 1MB */
		if (PAGE_SHIFT < 20)
			numentries = round_up(numentries, (1<<20)/PAGE_SIZE);
L
Linus Torvalds 已提交
5913 5914 5915 5916 5917 5918

		/* limit to 1 bucket per 2^scale bytes of low memory */
		if (scale > PAGE_SHIFT)
			numentries >>= (scale - PAGE_SHIFT);
		else
			numentries <<= (PAGE_SHIFT - scale);
5919 5920

		/* Make sure we've got at least a 0-order allocation.. */
5921 5922 5923 5924 5925 5926 5927 5928
		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))
5929
			numentries = PAGE_SIZE / bucketsize;
L
Linus Torvalds 已提交
5930
	}
5931
	numentries = roundup_pow_of_two(numentries);
L
Linus Torvalds 已提交
5932 5933 5934 5935 5936 5937

	/* 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);
	}
5938
	max = min(max, 0x80000000ULL);
L
Linus Torvalds 已提交
5939

5940 5941
	if (numentries < low_limit)
		numentries = low_limit;
L
Linus Torvalds 已提交
5942 5943 5944
	if (numentries > max)
		numentries = max;

5945
	log2qty = ilog2(numentries);
L
Linus Torvalds 已提交
5946 5947 5948 5949

	do {
		size = bucketsize << log2qty;
		if (flags & HASH_EARLY)
5950
			table = memblock_virt_alloc_nopanic(size, 0);
L
Linus Torvalds 已提交
5951 5952 5953
		else if (hashdist)
			table = __vmalloc(size, GFP_ATOMIC, PAGE_KERNEL);
		else {
5954 5955
			/*
			 * If bucketsize is not a power-of-two, we may free
5956 5957
			 * some pages at the end of hash table which
			 * alloc_pages_exact() automatically does
5958
			 */
5959
			if (get_order(size) < MAX_ORDER) {
5960
				table = alloc_pages_exact(size, GFP_ATOMIC);
5961 5962
				kmemleak_alloc(table, size, 1, GFP_ATOMIC);
			}
L
Linus Torvalds 已提交
5963 5964 5965 5966 5967 5968
		}
	} while (!table && size > PAGE_SIZE && --log2qty);

	if (!table)
		panic("Failed to allocate %s hash table\n", tablename);

5969
	printk(KERN_INFO "%s hash table entries: %ld (order: %d, %lu bytes)\n",
L
Linus Torvalds 已提交
5970
	       tablename,
5971
	       (1UL << log2qty),
5972
	       ilog2(size) - PAGE_SHIFT,
L
Linus Torvalds 已提交
5973 5974 5975 5976 5977 5978 5979 5980 5981
	       size);

	if (_hash_shift)
		*_hash_shift = log2qty;
	if (_hash_mask)
		*_hash_mask = (1 << log2qty) - 1;

	return table;
}
5982

5983 5984 5985 5986 5987 5988 5989 5990 5991 5992 5993 5994 5995 5996 5997
/* Return a pointer to the bitmap storing bits affecting a block of pages */
static inline unsigned long *get_pageblock_bitmap(struct zone *zone,
							unsigned long pfn)
{
#ifdef CONFIG_SPARSEMEM
	return __pfn_to_section(pfn)->pageblock_flags;
#else
	return zone->pageblock_flags;
#endif /* CONFIG_SPARSEMEM */
}

static inline int pfn_to_bitidx(struct zone *zone, unsigned long pfn)
{
#ifdef CONFIG_SPARSEMEM
	pfn &= (PAGES_PER_SECTION-1);
5998
	return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
5999
#else
6000
	pfn = pfn - round_down(zone->zone_start_pfn, pageblock_nr_pages);
6001
	return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS;
6002 6003 6004 6005
#endif /* CONFIG_SPARSEMEM */
}

/**
6006
 * get_pageblock_flags_group - Return the requested group of flags for the pageblock_nr_pages block of pages
6007 6008 6009 6010 6011 6012 6013 6014 6015 6016 6017 6018 6019 6020 6021 6022 6023 6024 6025 6026 6027 6028
 * @page: The page within the block of interest
 * @start_bitidx: The first bit of interest to retrieve
 * @end_bitidx: The last bit of interest
 * returns pageblock_bits flags
 */
unsigned long get_pageblock_flags_group(struct page *page,
					int start_bitidx, int end_bitidx)
{
	struct zone *zone;
	unsigned long *bitmap;
	unsigned long pfn, bitidx;
	unsigned long flags = 0;
	unsigned long value = 1;

	zone = page_zone(page);
	pfn = page_to_pfn(page);
	bitmap = get_pageblock_bitmap(zone, pfn);
	bitidx = pfn_to_bitidx(zone, pfn);

	for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)
		if (test_bit(bitidx + start_bitidx, bitmap))
			flags |= value;
6029

6030 6031 6032 6033
	return flags;
}

/**
6034
 * set_pageblock_flags_group - Set the requested group of flags for a pageblock_nr_pages block of pages
6035 6036 6037 6038 6039 6040 6041 6042 6043 6044 6045 6046 6047 6048 6049 6050 6051
 * @page: The page within the block of interest
 * @start_bitidx: The first bit of interest
 * @end_bitidx: The last bit of interest
 * @flags: The flags to set
 */
void set_pageblock_flags_group(struct page *page, unsigned long flags,
					int start_bitidx, int end_bitidx)
{
	struct zone *zone;
	unsigned long *bitmap;
	unsigned long pfn, bitidx;
	unsigned long value = 1;

	zone = page_zone(page);
	pfn = page_to_pfn(page);
	bitmap = get_pageblock_bitmap(zone, pfn);
	bitidx = pfn_to_bitidx(zone, pfn);
6052
	VM_BUG_ON_PAGE(!zone_spans_pfn(zone, pfn), page);
6053 6054 6055 6056 6057 6058 6059

	for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1)
		if (flags & value)
			__set_bit(bitidx + start_bitidx, bitmap);
		else
			__clear_bit(bitidx + start_bitidx, bitmap);
}
K
KAMEZAWA Hiroyuki 已提交
6060 6061

/*
6062 6063 6064
 * This function checks whether pageblock includes unmovable pages or not.
 * If @count is not zero, it is okay to include less @count unmovable pages
 *
6065
 * PageLRU check without isolation or lru_lock could race so that
6066 6067
 * MIGRATE_MOVABLE block might include unmovable pages. It means you can't
 * expect this function should be exact.
K
KAMEZAWA Hiroyuki 已提交
6068
 */
6069 6070
bool has_unmovable_pages(struct zone *zone, struct page *page, int count,
			 bool skip_hwpoisoned_pages)
6071 6072
{
	unsigned long pfn, iter, found;
6073 6074
	int mt;

6075 6076
	/*
	 * For avoiding noise data, lru_add_drain_all() should be called
6077
	 * If ZONE_MOVABLE, the zone never contains unmovable pages
6078 6079
	 */
	if (zone_idx(zone) == ZONE_MOVABLE)
6080
		return false;
6081 6082
	mt = get_pageblock_migratetype(page);
	if (mt == MIGRATE_MOVABLE || is_migrate_cma(mt))
6083
		return false;
6084 6085 6086 6087 6088

	pfn = page_to_pfn(page);
	for (found = 0, iter = 0; iter < pageblock_nr_pages; iter++) {
		unsigned long check = pfn + iter;

6089
		if (!pfn_valid_within(check))
6090
			continue;
6091

6092
		page = pfn_to_page(check);
6093 6094 6095 6096 6097 6098 6099 6100 6101 6102 6103

		/*
		 * 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;
		}

6104 6105 6106 6107 6108 6109 6110
		/*
		 * 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->_count is zero at all time.
		 */
		if (!atomic_read(&page->_count)) {
6111 6112 6113 6114
			if (PageBuddy(page))
				iter += (1 << page_order(page)) - 1;
			continue;
		}
6115

6116 6117 6118 6119 6120 6121 6122
		/*
		 * The HWPoisoned page may be not in buddy system, and
		 * page_count() is not 0.
		 */
		if (skip_hwpoisoned_pages && PageHWPoison(page))
			continue;

6123 6124 6125 6126 6127 6128 6129 6130 6131 6132 6133 6134 6135 6136 6137 6138
		if (!PageLRU(page))
			found++;
		/*
		 * If there are RECLAIMABLE pages, we need to check it.
		 * But now, memory offline itself doesn't call shrink_slab()
		 * 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)
6139
			return true;
6140
	}
6141
	return false;
6142 6143 6144 6145
}

bool is_pageblock_removable_nolock(struct page *page)
{
6146 6147
	struct zone *zone;
	unsigned long pfn;
6148 6149 6150 6151 6152

	/*
	 * 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.
6153 6154
	 * We have to take care about the node as well. If the node is offline
	 * its NODE_DATA will be NULL - see page_zone.
6155
	 */
6156 6157 6158 6159 6160
	if (!node_online(page_to_nid(page)))
		return false;

	zone = page_zone(page);
	pfn = page_to_pfn(page);
6161
	if (!zone_spans_pfn(zone, pfn))
6162 6163
		return false;

6164
	return !has_unmovable_pages(zone, page, 0, true);
K
KAMEZAWA Hiroyuki 已提交
6165
}
K
KAMEZAWA Hiroyuki 已提交
6166

6167 6168 6169 6170 6171 6172 6173 6174 6175 6176 6177 6178 6179 6180 6181
#ifdef 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. */
6182 6183
static int __alloc_contig_migrate_range(struct compact_control *cc,
					unsigned long start, unsigned long end)
6184 6185
{
	/* This function is based on compact_zone() from compaction.c. */
6186
	unsigned long nr_reclaimed;
6187 6188 6189 6190
	unsigned long pfn = start;
	unsigned int tries = 0;
	int ret = 0;

6191
	migrate_prep();
6192

6193
	while (pfn < end || !list_empty(&cc->migratepages)) {
6194 6195 6196 6197 6198
		if (fatal_signal_pending(current)) {
			ret = -EINTR;
			break;
		}

6199 6200 6201
		if (list_empty(&cc->migratepages)) {
			cc->nr_migratepages = 0;
			pfn = isolate_migratepages_range(cc->zone, cc,
M
Minchan Kim 已提交
6202
							 pfn, end, true);
6203 6204 6205 6206 6207 6208 6209 6210 6211 6212
			if (!pfn) {
				ret = -EINTR;
				break;
			}
			tries = 0;
		} else if (++tries == 5) {
			ret = ret < 0 ? ret : -EBUSY;
			break;
		}

6213 6214 6215
		nr_reclaimed = reclaim_clean_pages_from_list(cc->zone,
							&cc->migratepages);
		cc->nr_migratepages -= nr_reclaimed;
6216

6217 6218
		ret = migrate_pages(&cc->migratepages, alloc_migrate_target,
				    0, MIGRATE_SYNC, MR_CMA);
6219
	}
6220 6221 6222 6223 6224
	if (ret < 0) {
		putback_movable_pages(&cc->migratepages);
		return ret;
	}
	return 0;
6225 6226 6227 6228 6229 6230
}

/**
 * alloc_contig_range() -- tries to allocate given range of pages
 * @start:	start PFN to allocate
 * @end:	one-past-the-last PFN to allocate
6231 6232 6233 6234
 * @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.
6235 6236 6237 6238 6239 6240 6241 6242 6243 6244 6245 6246
 *
 * 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().
 */
6247 6248
int alloc_contig_range(unsigned long start, unsigned long end,
		       unsigned migratetype)
6249 6250 6251 6252
{
	unsigned long outer_start, outer_end;
	int ret = 0, order;

6253 6254 6255 6256 6257 6258 6259 6260 6261
	struct compact_control cc = {
		.nr_migratepages = 0,
		.order = -1,
		.zone = page_zone(pfn_to_page(start)),
		.sync = true,
		.ignore_skip_hint = true,
	};
	INIT_LIST_HEAD(&cc.migratepages);

6262 6263 6264 6265 6266 6267 6268 6269 6270 6271 6272 6273 6274 6275 6276 6277 6278 6279 6280 6281 6282 6283 6284 6285 6286
	/*
	 * 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),
6287 6288
				       pfn_max_align_up(end), migratetype,
				       false);
6289
	if (ret)
6290
		return ret;
6291

6292
	ret = __alloc_contig_migrate_range(&cc, start, end);
6293 6294 6295 6296 6297 6298 6299 6300 6301 6302 6303 6304 6305 6306 6307 6308 6309 6310 6311 6312 6313 6314 6315 6316 6317 6318 6319 6320 6321 6322 6323 6324 6325 6326
	if (ret)
		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();

	order = 0;
	outer_start = start;
	while (!PageBuddy(pfn_to_page(outer_start))) {
		if (++order >= MAX_ORDER) {
			ret = -EBUSY;
			goto done;
		}
		outer_start &= ~0UL << order;
	}

	/* Make sure the range is really isolated. */
6327
	if (test_pages_isolated(outer_start, end, false)) {
6328 6329 6330 6331 6332 6333
		pr_warn("alloc_contig_range test_pages_isolated(%lx, %lx) failed\n",
		       outer_start, end);
		ret = -EBUSY;
		goto done;
	}

6334 6335

	/* Grab isolated pages from freelists. */
6336
	outer_end = isolate_freepages_range(&cc, outer_start, end);
6337 6338 6339 6340 6341 6342 6343 6344 6345 6346 6347 6348 6349
	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),
6350
				pfn_max_align_up(end), migratetype);
6351 6352 6353 6354 6355
	return ret;
}

void free_contig_range(unsigned long pfn, unsigned nr_pages)
{
6356 6357 6358 6359 6360 6361 6362 6363 6364
	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);
6365 6366 6367
}
#endif

6368
#ifdef CONFIG_MEMORY_HOTPLUG
6369 6370 6371 6372
/*
 * The zone indicated has a new number of managed_pages; batch sizes and percpu
 * page high values need to be recalulated.
 */
6373 6374
void __meminit zone_pcp_update(struct zone *zone)
{
6375
	unsigned cpu;
6376
	mutex_lock(&pcp_batch_high_lock);
6377
	for_each_possible_cpu(cpu)
6378 6379
		pageset_set_high_and_batch(zone,
				per_cpu_ptr(zone->pageset, cpu));
6380
	mutex_unlock(&pcp_batch_high_lock);
6381 6382 6383
}
#endif

6384 6385 6386
void zone_pcp_reset(struct zone *zone)
{
	unsigned long flags;
6387 6388
	int cpu;
	struct per_cpu_pageset *pset;
6389 6390 6391 6392

	/* avoid races with drain_pages()  */
	local_irq_save(flags);
	if (zone->pageset != &boot_pageset) {
6393 6394 6395 6396
		for_each_online_cpu(cpu) {
			pset = per_cpu_ptr(zone->pageset, cpu);
			drain_zonestat(zone, pset);
		}
6397 6398 6399 6400 6401 6402
		free_percpu(zone->pageset);
		zone->pageset = &boot_pageset;
	}
	local_irq_restore(flags);
}

6403
#ifdef CONFIG_MEMORY_HOTREMOVE
K
KAMEZAWA Hiroyuki 已提交
6404 6405 6406 6407 6408 6409 6410 6411 6412 6413 6414 6415 6416 6417 6418 6419 6420 6421 6422 6423 6424 6425 6426 6427 6428 6429
/*
 * All pages in the range must be isolated before calling this.
 */
void
__offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn)
{
	struct page *page;
	struct zone *zone;
	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);
6430 6431 6432 6433 6434 6435 6436 6437 6438 6439
		/*
		 * 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;
		}

K
KAMEZAWA Hiroyuki 已提交
6440 6441 6442 6443 6444 6445 6446 6447 6448 6449 6450 6451 6452 6453 6454 6455 6456
		BUG_ON(page_count(page));
		BUG_ON(!PageBuddy(page));
		order = page_order(page);
#ifdef CONFIG_DEBUG_VM
		printk(KERN_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
6457 6458 6459 6460 6461 6462 6463 6464 6465 6466 6467 6468 6469 6470 6471 6472 6473 6474 6475 6476 6477

#ifdef CONFIG_MEMORY_FAILURE
bool is_free_buddy_page(struct page *page)
{
	struct zone *zone = page_zone(page);
	unsigned long pfn = page_to_pfn(page);
	unsigned long flags;
	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;
}
#endif
6478

A
Andrew Morton 已提交
6479
static const struct trace_print_flags pageflag_names[] = {
6480 6481 6482 6483 6484 6485 6486 6487 6488 6489 6490 6491 6492 6493 6494 6495 6496 6497 6498 6499 6500 6501 6502 6503 6504 6505 6506 6507 6508 6509 6510 6511 6512
	{1UL << PG_locked,		"locked"	},
	{1UL << PG_error,		"error"		},
	{1UL << PG_referenced,		"referenced"	},
	{1UL << PG_uptodate,		"uptodate"	},
	{1UL << PG_dirty,		"dirty"		},
	{1UL << PG_lru,			"lru"		},
	{1UL << PG_active,		"active"	},
	{1UL << PG_slab,		"slab"		},
	{1UL << PG_owner_priv_1,	"owner_priv_1"	},
	{1UL << PG_arch_1,		"arch_1"	},
	{1UL << PG_reserved,		"reserved"	},
	{1UL << PG_private,		"private"	},
	{1UL << PG_private_2,		"private_2"	},
	{1UL << PG_writeback,		"writeback"	},
#ifdef CONFIG_PAGEFLAGS_EXTENDED
	{1UL << PG_head,		"head"		},
	{1UL << PG_tail,		"tail"		},
#else
	{1UL << PG_compound,		"compound"	},
#endif
	{1UL << PG_swapcache,		"swapcache"	},
	{1UL << PG_mappedtodisk,	"mappedtodisk"	},
	{1UL << PG_reclaim,		"reclaim"	},
	{1UL << PG_swapbacked,		"swapbacked"	},
	{1UL << PG_unevictable,		"unevictable"	},
#ifdef CONFIG_MMU
	{1UL << PG_mlocked,		"mlocked"	},
#endif
#ifdef CONFIG_ARCH_USES_PG_UNCACHED
	{1UL << PG_uncached,		"uncached"	},
#endif
#ifdef CONFIG_MEMORY_FAILURE
	{1UL << PG_hwpoison,		"hwpoison"	},
6513 6514 6515
#endif
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
	{1UL << PG_compound_lock,	"compound_lock"	},
6516 6517 6518 6519 6520 6521 6522 6523 6524
#endif
};

static void dump_page_flags(unsigned long flags)
{
	const char *delim = "";
	unsigned long mask;
	int i;

A
Andrew Morton 已提交
6525
	BUILD_BUG_ON(ARRAY_SIZE(pageflag_names) != __NR_PAGEFLAGS);
6526

6527 6528 6529 6530 6531
	printk(KERN_ALERT "page flags: %#lx(", flags);

	/* remove zone id */
	flags &= (1UL << NR_PAGEFLAGS) - 1;

A
Andrew Morton 已提交
6532
	for (i = 0; i < ARRAY_SIZE(pageflag_names) && flags; i++) {
6533 6534 6535 6536 6537 6538 6539 6540 6541 6542 6543 6544 6545 6546 6547 6548 6549

		mask = pageflag_names[i].mask;
		if ((flags & mask) != mask)
			continue;

		flags &= ~mask;
		printk("%s%s", delim, pageflag_names[i].name);
		delim = "|";
	}

	/* check for left over flags */
	if (flags)
		printk("%s%#lx", delim, flags);

	printk(")\n");
}

6550 6551
void dump_page_badflags(struct page *page, const char *reason,
		unsigned long badflags)
6552 6553 6554
{
	printk(KERN_ALERT
	       "page:%p count:%d mapcount:%d mapping:%p index:%#lx\n",
6555
		page, atomic_read(&page->_count), page_mapcount(page),
6556 6557
		page->mapping, page->index);
	dump_page_flags(page->flags);
6558 6559 6560 6561 6562 6563
	if (reason)
		pr_alert("page dumped because: %s\n", reason);
	if (page->flags & badflags) {
		pr_alert("bad because of flags:\n");
		dump_page_flags(page->flags & badflags);
	}
6564
	mem_cgroup_print_bad_page(page);
6565
}
6566

6567
void dump_page(struct page *page, const char *reason)
6568 6569 6570
{
	dump_page_badflags(page, reason, 0);
}
6571
EXPORT_SYMBOL_GPL(dump_page);