page_alloc.c

EXPORT_SYMBOL(__alloc_pages);

/*
 * Common helper functions.
 */
fastcall unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order)
{
	struct page * page;
	page = alloc_pages(gfp_mask, order);
	if (!page)
		return 0;
	return (unsigned long) page_address(page);
}

EXPORT_SYMBOL(__get_free_pages);

fastcall unsigned long get_zeroed_page(gfp_t gfp_mask)
{
	struct page * page;

	/*
	 * get_zeroed_page() returns a 32-bit address, which cannot represent
	 * a highmem page
	 */
	BUG_ON((gfp_mask & __GFP_HIGHMEM) != 0);

	page = alloc_pages(gfp_mask | __GFP_ZERO, 0);
	if (page)
		return (unsigned long) page_address(page);
	return 0;
}

EXPORT_SYMBOL(get_zeroed_page);

void __pagevec_free(struct pagevec *pvec)
{
	int i = pagevec_count(pvec);

	while (--i >= 0)
		free_hot_cold_page(pvec->pages[i], pvec->cold);
}

fastcall void __free_pages(struct page *page, unsigned int order)
{
	if (put_page_testzero(page)) {
		if (order == 0)
			free_hot_page(page);
		else
			__free_pages_ok(page, order);
	}
}

EXPORT_SYMBOL(__free_pages);

fastcall void free_pages(unsigned long addr, unsigned int order)
{
	if (addr != 0) {
		BUG_ON(!virt_addr_valid((void *)addr));
		__free_pages(virt_to_page((void *)addr), order);
	}
}

EXPORT_SYMBOL(free_pages);

/*
 * Total amount of free (allocatable) RAM:
 */
unsigned int nr_free_pages(void)
{
	unsigned int sum = 0;
	struct zone *zone;

	for_each_zone(zone)
		sum += zone->free_pages;

	return sum;
}

EXPORT_SYMBOL(nr_free_pages);

#ifdef CONFIG_NUMA
unsigned int nr_free_pages_pgdat(pg_data_t *pgdat)
{
	unsigned int i, sum = 0;

	for (i = 0; i < MAX_NR_ZONES; i++)
		sum += pgdat->node_zones[i].free_pages;

	return sum;
}
#endif

static unsigned int nr_free_zone_pages(int offset)
{
	/* Just pick one node, since fallback list is circular */
	pg_data_t *pgdat = NODE_DATA(numa_node_id());
	unsigned int sum = 0;

	struct zonelist *zonelist = pgdat->node_zonelists + offset;
	struct zone **zonep = zonelist->zones;
	struct zone *zone;

	for (zone = *zonep++; zone; zone = *zonep++) {
		unsigned long size = zone->present_pages;
		unsigned long high = zone->pages_high;
		if (size > high)
			sum += size - high;
	}

	return sum;
}

/*
 * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL
 */
unsigned int nr_free_buffer_pages(void)
{
	return nr_free_zone_pages(gfp_zone(GFP_USER));
}

/*
 * Amount of free RAM allocatable within all zones
 */
unsigned int nr_free_pagecache_pages(void)
{
	return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER));
}

#ifdef CONFIG_HIGHMEM
unsigned int nr_free_highpages (void)
{
	pg_data_t *pgdat;
	unsigned int pages = 0;

	for_each_pgdat(pgdat)
		pages += pgdat->node_zones[ZONE_HIGHMEM].free_pages;

	return pages;
}
#endif

#ifdef CONFIG_NUMA
static void show_node(struct zone *zone)
{
	printk("Node %d ", zone->zone_pgdat->node_id);
}
#else
#define show_node(zone)	do { } while (0)
#endif

/*
 * Accumulate the page_state information across all CPUs.
 * The result is unavoidably approximate - it can change
 * during and after execution of this function.
 */
static DEFINE_PER_CPU(struct page_state, page_states) = {0};

atomic_t nr_pagecache = ATOMIC_INIT(0);
EXPORT_SYMBOL(nr_pagecache);
#ifdef CONFIG_SMP
DEFINE_PER_CPU(long, nr_pagecache_local) = 0;
#endif

void __get_page_state(struct page_state *ret, int nr, cpumask_t *cpumask)
{
	int cpu = 0;

	memset(ret, 0, sizeof(*ret));
	cpus_and(*cpumask, *cpumask, cpu_online_map);

	cpu = first_cpu(*cpumask);
	while (cpu < NR_CPUS) {
		unsigned long *in, *out, off;

		in = (unsigned long *)&per_cpu(page_states, cpu);

		cpu = next_cpu(cpu, *cpumask);

		if (cpu < NR_CPUS)
			prefetch(&per_cpu(page_states, cpu));

		out = (unsigned long *)ret;
		for (off = 0; off < nr; off++)
			*out++ += *in++;
	}
}

void get_page_state_node(struct page_state *ret, int node)
{
	int nr;
	cpumask_t mask = node_to_cpumask(node);

	nr = offsetof(struct page_state, GET_PAGE_STATE_LAST);
	nr /= sizeof(unsigned long);

	__get_page_state(ret, nr+1, &mask);
}

void get_page_state(struct page_state *ret)
{
	int nr;
	cpumask_t mask = CPU_MASK_ALL;

	nr = offsetof(struct page_state, GET_PAGE_STATE_LAST);
	nr /= sizeof(unsigned long);

	__get_page_state(ret, nr + 1, &mask);
}

void get_full_page_state(struct page_state *ret)
{
	cpumask_t mask = CPU_MASK_ALL;

	__get_page_state(ret, sizeof(*ret) / sizeof(unsigned long), &mask);
}

unsigned long __read_page_state(unsigned long offset)
{
	unsigned long ret = 0;
	int cpu;

	for_each_online_cpu(cpu) {
		unsigned long in;

		in = (unsigned long)&per_cpu(page_states, cpu) + offset;
		ret += *((unsigned long *)in);
	}
	return ret;
}

void __mod_page_state(unsigned long offset, unsigned long delta)
{
	unsigned long flags;
	void* ptr;

	local_irq_save(flags);
	ptr = &__get_cpu_var(page_states);
	*(unsigned long*)(ptr + offset) += delta;
	local_irq_restore(flags);
}

EXPORT_SYMBOL(__mod_page_state);

void __get_zone_counts(unsigned long *active, unsigned long *inactive,
			unsigned long *free, struct pglist_data *pgdat)
{
	struct zone *zones = pgdat->node_zones;
	int i;

	*active = 0;
	*inactive = 0;
	*free = 0;
	for (i = 0; i < MAX_NR_ZONES; i++) {
		*active += zones[i].nr_active;
		*inactive += zones[i].nr_inactive;
		*free += zones[i].free_pages;
	}
}

void get_zone_counts(unsigned long *active,
		unsigned long *inactive, unsigned long *free)
{
	struct pglist_data *pgdat;

	*active = 0;
	*inactive = 0;
	*free = 0;
	for_each_pgdat(pgdat) {
		unsigned long l, m, n;
		__get_zone_counts(&l, &m, &n, pgdat);
		*active += l;
		*inactive += m;
		*free += n;
	}
}

void si_meminfo(struct sysinfo *val)
{
	val->totalram = totalram_pages;
	val->sharedram = 0;
	val->freeram = nr_free_pages();
	val->bufferram = nr_blockdev_pages();
#ifdef CONFIG_HIGHMEM
	val->totalhigh = totalhigh_pages;
	val->freehigh = nr_free_highpages();
#else
	val->totalhigh = 0;
	val->freehigh = 0;
#endif
	val->mem_unit = PAGE_SIZE;
}

EXPORT_SYMBOL(si_meminfo);

#ifdef CONFIG_NUMA
void si_meminfo_node(struct sysinfo *val, int nid)
{
	pg_data_t *pgdat = NODE_DATA(nid);

	val->totalram = pgdat->node_present_pages;
	val->freeram = nr_free_pages_pgdat(pgdat);
	val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].present_pages;
	val->freehigh = pgdat->node_zones[ZONE_HIGHMEM].free_pages;
	val->mem_unit = PAGE_SIZE;
}
#endif

#define K(x) ((x) << (PAGE_SHIFT-10))

/*
 * 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.
 */
void show_free_areas(void)
{
	struct page_state ps;
	int cpu, temperature;
	unsigned long active;
	unsigned long inactive;
	unsigned long free;
	struct zone *zone;

	for_each_zone(zone) {
		show_node(zone);
		printk("%s per-cpu:", zone->name);

		if (!zone->present_pages) {
			printk(" empty\n");
			continue;
		} else
			printk("\n");

		for_each_online_cpu(cpu) {
			struct per_cpu_pageset *pageset;

			pageset = zone_pcp(zone, cpu);

			for (temperature = 0; temperature < 2; temperature++)
				printk("cpu %d %s: low %d, high %d, batch %d used:%d\n",
					cpu,
					temperature ? "cold" : "hot",
					pageset->pcp[temperature].low,
					pageset->pcp[temperature].high,
					pageset->pcp[temperature].batch,
					pageset->pcp[temperature].count);
		}
	}

	get_page_state(&ps);
	get_zone_counts(&active, &inactive, &free);

	printk("Free pages: %11ukB (%ukB HighMem)\n",
		K(nr_free_pages()),
		K(nr_free_highpages()));

	printk("Active:%lu inactive:%lu dirty:%lu writeback:%lu "
		"unstable:%lu free:%u slab:%lu mapped:%lu pagetables:%lu\n",
		active,
		inactive,
		ps.nr_dirty,
		ps.nr_writeback,
		ps.nr_unstable,
		nr_free_pages(),
		ps.nr_slab,
		ps.nr_mapped,
		ps.nr_page_table_pages);

	for_each_zone(zone) {
		int i;

		show_node(zone);
		printk("%s"
			" free:%lukB"
			" min:%lukB"
			" low:%lukB"
			" high:%lukB"
			" active:%lukB"
			" inactive:%lukB"
			" present:%lukB"
			" pages_scanned:%lu"
			" all_unreclaimable? %s"
			"\n",
			zone->name,
			K(zone->free_pages),
			K(zone->pages_min),
			K(zone->pages_low),
			K(zone->pages_high),
			K(zone->nr_active),
			K(zone->nr_inactive),
			K(zone->present_pages),
			zone->pages_scanned,
			(zone->all_unreclaimable ? "yes" : "no")
			);
		printk("lowmem_reserve[]:");
		for (i = 0; i < MAX_NR_ZONES; i++)
			printk(" %lu", zone->lowmem_reserve[i]);
		printk("\n");
	}

	for_each_zone(zone) {
 		unsigned long nr, flags, order, total = 0;

		show_node(zone);
		printk("%s: ", zone->name);
		if (!zone->present_pages) {
			printk("empty\n");
			continue;
		}

		spin_lock_irqsave(&zone->lock, flags);
		for (order = 0; order < MAX_ORDER; order++) {
			nr = zone->free_area[order].nr_free;
			total += nr << order;
			printk("%lu*%lukB ", nr, K(1UL) << order);
		}
		spin_unlock_irqrestore(&zone->lock, flags);
		printk("= %lukB\n", K(total));
	}

	show_swap_cache_info();
}

/*
 * Builds allocation fallback zone lists.
 */
static int __init build_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist, int j, int k)
{
	switch (k) {
		struct zone *zone;
	default:
		BUG();
	case ZONE_HIGHMEM:
		zone = pgdat->node_zones + ZONE_HIGHMEM;
		if (zone->present_pages) {
#ifndef CONFIG_HIGHMEM
			BUG();
#endif
			zonelist->zones[j++] = zone;
		}
	case ZONE_NORMAL:
		zone = pgdat->node_zones + ZONE_NORMAL;
		if (zone->present_pages)
			zonelist->zones[j++] = zone;
	case ZONE_DMA32:
		zone = pgdat->node_zones + ZONE_DMA32;
		if (zone->present_pages)
			zonelist->zones[j++] = zone;
	case ZONE_DMA:
		zone = pgdat->node_zones + ZONE_DMA;
		if (zone->present_pages)
			zonelist->zones[j++] = zone;
	}

	return j;
}

static inline int highest_zone(int zone_bits)
{
	int res = ZONE_NORMAL;
	if (zone_bits & (__force int)__GFP_HIGHMEM)
		res = ZONE_HIGHMEM;
	if (zone_bits & (__force int)__GFP_DMA32)
		res = ZONE_DMA32;
	if (zone_bits & (__force int)__GFP_DMA)
		res = ZONE_DMA;
	return res;
}

#ifdef CONFIG_NUMA
#define MAX_NODE_LOAD (num_online_nodes())
static int __initdata node_load[MAX_NUMNODES];
/**
 * find_next_best_node - find the next node that should appear in a given node's fallback list
 * @node: node whose fallback list we're appending
 * @used_node_mask: nodemask_t of already used nodes
 *
 * We use a number of factors to determine which is the next node that should
 * appear on a given node's fallback list.  The node should not have appeared
 * already in @node's fallback list, and it should be the next closest node
 * according to the distance array (which contains arbitrary distance values
 * from each node to each node in the system), and should also prefer nodes
 * with no CPUs, since presumably they'll have very little allocation pressure
 * on them otherwise.
 * It returns -1 if no node is found.
 */
static int __init find_next_best_node(int node, nodemask_t *used_node_mask)
{
	int i, n, val;
	int min_val = INT_MAX;
	int best_node = -1;

	for_each_online_node(i) {
		cpumask_t tmp;

		/* Start from local node */
		n = (node+i) % num_online_nodes();

		/* Don't want a node to appear more than once */
		if (node_isset(n, *used_node_mask))
			continue;

		/* Use the local node if we haven't already */
		if (!node_isset(node, *used_node_mask)) {
			best_node = node;
			break;
		}

		/* Use the distance array to find the distance */
		val = node_distance(node, n);

		/* Give preference to headless and unused nodes */
		tmp = node_to_cpumask(n);
		if (!cpus_empty(tmp))
			val += PENALTY_FOR_NODE_WITH_CPUS;

		/* Slight preference for less loaded node */
		val *= (MAX_NODE_LOAD*MAX_NUMNODES);
		val += node_load[n];

		if (val < min_val) {
			min_val = val;
			best_node = n;
		}
	}

	if (best_node >= 0)
		node_set(best_node, *used_node_mask);

	return best_node;
}

static void __init build_zonelists(pg_data_t *pgdat)
{
	int i, j, k, node, local_node;
	int prev_node, load;
	struct zonelist *zonelist;
	nodemask_t used_mask;

	/* initialize zonelists */
	for (i = 0; i < GFP_ZONETYPES; i++) {
		zonelist = pgdat->node_zonelists + i;
		zonelist->zones[0] = NULL;
	}

	/* NUMA-aware ordering of nodes */
	local_node = pgdat->node_id;
	load = num_online_nodes();
	prev_node = local_node;
	nodes_clear(used_mask);
	while ((node = find_next_best_node(local_node, &used_mask)) >= 0) {
		/*
		 * We don't want to pressure a particular node.
		 * So adding penalty to the first node in same
		 * distance group to make it round-robin.
		 */
		if (node_distance(local_node, node) !=
				node_distance(local_node, prev_node))
			node_load[node] += load;
		prev_node = node;
		load--;
		for (i = 0; i < GFP_ZONETYPES; i++) {
			zonelist = pgdat->node_zonelists + i;
			for (j = 0; zonelist->zones[j] != NULL; j++);

			k = highest_zone(i);

	 		j = build_zonelists_node(NODE_DATA(node), zonelist, j, k);
			zonelist->zones[j] = NULL;
		}
	}
}

#else	/* CONFIG_NUMA */

static void __init build_zonelists(pg_data_t *pgdat)
{
	int i, j, k, node, local_node;

	local_node = pgdat->node_id;
	for (i = 0; i < GFP_ZONETYPES; i++) {
		struct zonelist *zonelist;

		zonelist = pgdat->node_zonelists + i;

		j = 0;
		k = highest_zone(i);
 		j = build_zonelists_node(pgdat, zonelist, j, k);
 		/*
 		 * Now we build the zonelist so that it contains the zones
 		 * of all the other nodes.
 		 * We don't want to pressure a particular node, so when
 		 * building the zones for node N, we make sure that the
 		 * zones coming right after the local ones are those from
 		 * node N+1 (modulo N)
 		 */
		for (node = local_node + 1; node < MAX_NUMNODES; node++) {
			if (!node_online(node))
				continue;
			j = build_zonelists_node(NODE_DATA(node), zonelist, j, k);
		}
		for (node = 0; node < local_node; node++) {
			if (!node_online(node))
				continue;
			j = build_zonelists_node(NODE_DATA(node), zonelist, j, k);
		}

		zonelist->zones[j] = NULL;
	}
}

#endif	/* CONFIG_NUMA */

void __init build_all_zonelists(void)
{
	int i;

	for_each_online_node(i)
		build_zonelists(NODE_DATA(i));
	printk("Built %i zonelists\n", num_online_nodes());
	cpuset_init_current_mems_allowed();
}

/*
 * 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

static inline unsigned long wait_table_size(unsigned long pages)
{
	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);
}

/*
 * 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);
}

#define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1))

static void __init calculate_zone_totalpages(struct pglist_data *pgdat,
		unsigned long *zones_size, unsigned long *zholes_size)
{
	unsigned long realtotalpages, totalpages = 0;
	int i;

	for (i = 0; i < MAX_NR_ZONES; i++)
		totalpages += zones_size[i];
	pgdat->node_spanned_pages = totalpages;

	realtotalpages = totalpages;
	if (zholes_size)
		for (i = 0; i < MAX_NR_ZONES; i++)
			realtotalpages -= zholes_size[i];
	pgdat->node_present_pages = realtotalpages;
	printk(KERN_DEBUG "On node %d totalpages: %lu\n", pgdat->node_id, realtotalpages);
}


/*
 * Initially all pages are reserved - free ones are freed
 * up by free_all_bootmem() once the early boot process is
 * done. Non-atomic initialization, single-pass.
 */
void __devinit memmap_init_zone(unsigned long size, int nid, unsigned long zone,
		unsigned long start_pfn)
{
	struct page *page;
	unsigned long end_pfn = start_pfn + size;
	unsigned long pfn;

	for (pfn = start_pfn; pfn < end_pfn; pfn++, page++) {
		if (!early_pfn_valid(pfn))
			continue;
		if (!early_pfn_in_nid(pfn, nid))
			continue;
		page = pfn_to_page(pfn);
		set_page_links(page, zone, nid, pfn);
		set_page_count(page, 1);
		reset_page_mapcount(page);
		SetPageReserved(page);
		INIT_LIST_HEAD(&page->lru);
#ifdef WANT_PAGE_VIRTUAL
		/* The shift won't overflow because ZONE_NORMAL is below 4G. */
		if (!is_highmem_idx(zone))
			set_page_address(page, __va(pfn << PAGE_SHIFT));
#endif
	}
}

void zone_init_free_lists(struct pglist_data *pgdat, struct zone *zone,
				unsigned long size)
{
	int order;
	for (order = 0; order < MAX_ORDER ; order++) {
		INIT_LIST_HEAD(&zone->free_area[order].free_list);
		zone->free_area[order].nr_free = 0;
	}
}

#define ZONETABLE_INDEX(x, zone_nr)	((x << ZONES_SHIFT) | zone_nr)
void zonetable_add(struct zone *zone, int nid, int zid, unsigned long pfn,
		unsigned long size)
{
	unsigned long snum = pfn_to_section_nr(pfn);
	unsigned long end = pfn_to_section_nr(pfn + size);

	if (FLAGS_HAS_NODE)
		zone_table[ZONETABLE_INDEX(nid, zid)] = zone;
	else
		for (; snum <= end; snum++)
			zone_table[ZONETABLE_INDEX(snum, zid)] = zone;
}

#ifndef __HAVE_ARCH_MEMMAP_INIT
#define memmap_init(size, nid, zone, start_pfn) \
	memmap_init_zone((size), (nid), (zone), (start_pfn))
#endif

static int __devinit zone_batchsize(struct zone *zone)
{
	int batch;

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

	/*
	 * We will be trying to allcoate bigger chunks of contiguous
	 * memory of the order of fls(batch).  This should result in
	 * better cache coloring.
	 *
	 * A sanity check also to ensure that batch is still in limits.
	 */
	batch = (1 << fls(batch + batch/2));

	if (fls(batch) >= (PAGE_SHIFT + MAX_ORDER - 2))
		batch = PAGE_SHIFT + ((MAX_ORDER - 1 - PAGE_SHIFT)/2);

	return batch;
}

inline void setup_pageset(struct per_cpu_pageset *p, unsigned long batch)
{
	struct per_cpu_pages *pcp;

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

	pcp = &p->pcp[0];		/* hot */
	pcp->count = 0;
	pcp->low = 0;
	pcp->high = 6 * batch;
	pcp->batch = max(1UL, 1 * batch);
	INIT_LIST_HEAD(&pcp->list);

	pcp = &p->pcp[1];		/* cold*/
	pcp->count = 0;
	pcp->low = 0;
	pcp->high = 2 * batch;
	pcp->batch = max(1UL, batch/2);
	INIT_LIST_HEAD(&pcp->list);
}

#ifdef CONFIG_NUMA
/*
 * Boot pageset table. One per cpu which is going to be used for all
 * zones and all nodes. The parameters will be set in such a way
 * that an item put on a list will immediately be handed over to
 * the buddy list. This is safe since pageset manipulation is done
 * with interrupts disabled.
 *
 * Some NUMA counter updates may also be caught by the boot pagesets.
 *
 * 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 struct per_cpu_pageset
	boot_pageset[NR_CPUS];

/*
 * Dynamically allocate memory for the
 * per cpu pageset array in struct zone.
 */
static int __devinit process_zones(int cpu)
{
	struct zone *zone, *dzone;

	for_each_zone(zone) {

		zone->pageset[cpu] = kmalloc_node(sizeof(struct per_cpu_pageset),
					 GFP_KERNEL, cpu_to_node(cpu));
		if (!zone->pageset[cpu])
			goto bad;

		setup_pageset(zone->pageset[cpu], zone_batchsize(zone));
	}

	return 0;
bad:
	for_each_zone(dzone) {
		if (dzone == zone)
			break;
		kfree(dzone->pageset[cpu]);
		dzone->pageset[cpu] = NULL;
	}
	return -ENOMEM;
}

static inline void free_zone_pagesets(int cpu)
{
#ifdef CONFIG_NUMA
	struct zone *zone;

	for_each_zone(zone) {
		struct per_cpu_pageset *pset = zone_pcp(zone, cpu);

		zone_pcp(zone, cpu) = NULL;
		kfree(pset);
	}
#endif
}

static int __devinit pageset_cpuup_callback(struct notifier_block *nfb,
		unsigned long action,
		void *hcpu)
{
	int cpu = (long)hcpu;
	int ret = NOTIFY_OK;

	switch (action) {
		case CPU_UP_PREPARE:
			if (process_zones(cpu))
				ret = NOTIFY_BAD;
			break;
		case CPU_UP_CANCELED:
		case CPU_DEAD:
			free_zone_pagesets(cpu);
			break;
		default:
			break;
	}
	return ret;
}

static struct notifier_block pageset_notifier =
	{ &pageset_cpuup_callback, NULL, 0 };

void __init setup_per_cpu_pageset()
{
	int err;

	/* Initialize per_cpu_pageset for cpu 0.
	 * A cpuup callback will do this for every cpu
	 * as it comes online
	 */
	err = process_zones(smp_processor_id());
	BUG_ON(err);
	register_cpu_notifier(&pageset_notifier);
}

#endif

static __devinit
void zone_wait_table_init(struct zone *zone, unsigned long zone_size_pages)
{
	int i;
	struct pglist_data *pgdat = zone->zone_pgdat;

	/*
	 * The per-page waitqueue mechanism uses hashed waitqueues
	 * per zone.
	 */
	zone->wait_table_size = wait_table_size(zone_size_pages);
	zone->wait_table_bits =	wait_table_bits(zone->wait_table_size);
	zone->wait_table = (wait_queue_head_t *)
		alloc_bootmem_node(pgdat, zone->wait_table_size
					* sizeof(wait_queue_head_t));

	for(i = 0; i < zone->wait_table_size; ++i)
		init_waitqueue_head(zone->wait_table + i);
}

static __devinit void zone_pcp_init(struct zone *zone)
{
	int cpu;
	unsigned long batch = zone_batchsize(zone);

	for (cpu = 0; cpu < NR_CPUS; cpu++) {
#ifdef CONFIG_NUMA
		/* Early boot. Slab allocator not functional yet */
		zone->pageset[cpu] = &boot_pageset[cpu];
		setup_pageset(&boot_pageset[cpu],0);
#else
		setup_pageset(zone_pcp(zone,cpu), batch);
#endif
	}
	printk(KERN_DEBUG "  %s zone: %lu pages, LIFO batch:%lu\n",
		zone->name, zone->present_pages, batch);
}

static __devinit void init_currently_empty_zone(struct zone *zone,
		unsigned long zone_start_pfn, unsigned long size)
{
	struct pglist_data *pgdat = zone->zone_pgdat;

	zone_wait_table_init(zone, size);
	pgdat->nr_zones = zone_idx(zone) + 1;

	zone->zone_mem_map = pfn_to_page(zone_start_pfn);
	zone->zone_start_pfn = zone_start_pfn;

	memmap_init(size, pgdat->node_id, zone_idx(zone), zone_start_pfn);

	zone_init_free_lists(pgdat, zone, zone->spanned_pages);
}

/*
 * Set up the zone data structures:
 *   - mark all pages reserved
 *   - mark all memory queues empty
 *   - clear the memory bitmaps
 */
static void __init free_area_init_core(struct pglist_data *pgdat,
		unsigned long *zones_size, unsigned long *zholes_size)
{
	unsigned long j;
	int nid = pgdat->node_id;
	unsigned long zone_start_pfn = pgdat->node_start_pfn;

	pgdat_resize_init(pgdat);
	pgdat->nr_zones = 0;
	init_waitqueue_head(&pgdat->kswapd_wait);
	pgdat->kswapd_max_order = 0;
	
	for (j = 0; j < MAX_NR_ZONES; j++) {
		struct zone *zone = pgdat->node_zones + j;
		unsigned long size, realsize;

		realsize = size = zones_size[j];
		if (zholes_size)
			realsize -= zholes_size[j];

		if (j < ZONE_HIGHMEM)
			nr_kernel_pages += realsize;
		nr_all_pages += realsize;

		zone->spanned_pages = size;
		zone->present_pages = realsize;
		zone->name = zone_names[j];
		spin_lock_init(&zone->lock);
		spin_lock_init(&zone->lru_lock);
		zone_seqlock_init(zone);
		zone->zone_pgdat = pgdat;
		zone->free_pages = 0;

		zone->temp_priority = zone->prev_priority = DEF_PRIORITY;

		zone_pcp_init(zone);
		INIT_LIST_HEAD(&zone->active_list);