1/*
  2 * linux/mm/mmzone.c
  3 *
  4 * management codes for pgdats, zones and page flags
  5 */
  6
  7
  8#include <linux/stddef.h>
  9#include <linux/mm.h>
 10#include <linux/mmzone.h>
 
 11
 12struct pglist_data *first_online_pgdat(void)
 13{
 14	return NODE_DATA(first_online_node);
 15}
 16
 17struct pglist_data *next_online_pgdat(struct pglist_data *pgdat)
 18{
 19	int nid = next_online_node(pgdat->node_id);
 20
 21	if (nid == MAX_NUMNODES)
 22		return NULL;
 23	return NODE_DATA(nid);
 24}
 25
 26/*
 27 * next_zone - helper magic for for_each_zone()
 28 */
 29struct zone *next_zone(struct zone *zone)
 30{
 31	pg_data_t *pgdat = zone->zone_pgdat;
 32
 33	if (zone < pgdat->node_zones + MAX_NR_ZONES - 1)
 34		zone++;
 35	else {
 36		pgdat = next_online_pgdat(pgdat);
 37		if (pgdat)
 38			zone = pgdat->node_zones;
 39		else
 40			zone = NULL;
 41	}
 42	return zone;
 43}
 44
 45static inline int zref_in_nodemask(struct zoneref *zref, nodemask_t *nodes)
 46{
 47#ifdef CONFIG_NUMA
 48	return node_isset(zonelist_node_idx(zref), *nodes);
 49#else
 50	return 1;
 51#endif /* CONFIG_NUMA */
 52}
 53
 54/* Returns the next zone at or below highest_zoneidx in a zonelist */
 55struct zoneref *next_zones_zonelist(struct zoneref *z,
 56					enum zone_type highest_zoneidx,
 57					nodemask_t *nodes)
 
 58{
 59	/*
 60	 * Find the next suitable zone to use for the allocation.
 61	 * Only filter based on nodemask if it's set
 62	 */
 63	if (likely(nodes == NULL))
 64		while (zonelist_zone_idx(z) > highest_zoneidx)
 65			z++;
 66	else
 67		while (zonelist_zone_idx(z) > highest_zoneidx ||
 68				(z->zone && !zref_in_nodemask(z, nodes)))
 69			z++;
 70
 
 71	return z;
 72}
 73
 74#ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
 75bool memmap_valid_within(unsigned long pfn,
 76					struct page *page, struct zone *zone)
 77{
 78	if (page_to_pfn(page) != pfn)
 79		return false;
 80
 81	if (page_zone(page) != zone)
 82		return false;
 83
 84	return true;
 85}
 86#endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
 87
 88void lruvec_init(struct lruvec *lruvec)
 89{
 90	enum lru_list lru;
 91
 92	memset(lruvec, 0, sizeof(struct lruvec));
 93
 94	for_each_lru(lru)
 95		INIT_LIST_HEAD(&lruvec->lists[lru]);
 96}
 97
 98#if defined(CONFIG_NUMA_BALANCING) && !defined(LAST_CPUPID_NOT_IN_PAGE_FLAGS)
 99int page_cpupid_xchg_last(struct page *page, int cpupid)
100{
101	unsigned long old_flags, flags;
102	int last_cpupid;
103
104	do {
105		old_flags = flags = page->flags;
106		last_cpupid = page_cpupid_last(page);
107
108		flags &= ~(LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT);
109		flags |= (cpupid & LAST_CPUPID_MASK) << LAST_CPUPID_PGSHIFT;
110	} while (unlikely(cmpxchg(&page->flags, old_flags, flags) != old_flags));
111
112	return last_cpupid;
113}
114#endif

 1/*
 2 * linux/mm/mmzone.c
 3 *
 4 * management codes for pgdats and zones.
 5 */
 6
 7
 8#include <linux/stddef.h>
 9#include <linux/mm.h>
10#include <linux/mmzone.h>
11#include <linux/module.h>
12
13struct pglist_data *first_online_pgdat(void)
14{
15	return NODE_DATA(first_online_node);
16}
17
18struct pglist_data *next_online_pgdat(struct pglist_data *pgdat)
19{
20	int nid = next_online_node(pgdat->node_id);
21
22	if (nid == MAX_NUMNODES)
23		return NULL;
24	return NODE_DATA(nid);
25}
26
27/*
28 * next_zone - helper magic for for_each_zone()
29 */
30struct zone *next_zone(struct zone *zone)
31{
32	pg_data_t *pgdat = zone->zone_pgdat;
33
34	if (zone < pgdat->node_zones + MAX_NR_ZONES - 1)
35		zone++;
36	else {
37		pgdat = next_online_pgdat(pgdat);
38		if (pgdat)
39			zone = pgdat->node_zones;
40		else
41			zone = NULL;
42	}
43	return zone;
44}
45
46static inline int zref_in_nodemask(struct zoneref *zref, nodemask_t *nodes)
47{
48#ifdef CONFIG_NUMA
49	return node_isset(zonelist_node_idx(zref), *nodes);
50#else
51	return 1;
52#endif /* CONFIG_NUMA */
53}
54
55/* Returns the next zone at or below highest_zoneidx in a zonelist */
56struct zoneref *next_zones_zonelist(struct zoneref *z,
57					enum zone_type highest_zoneidx,
58					nodemask_t *nodes,
59					struct zone **zone)
60{
61	/*
62	 * Find the next suitable zone to use for the allocation.
63	 * Only filter based on nodemask if it's set
64	 */
65	if (likely(nodes == NULL))
66		while (zonelist_zone_idx(z) > highest_zoneidx)
67			z++;
68	else
69		while (zonelist_zone_idx(z) > highest_zoneidx ||
70				(z->zone && !zref_in_nodemask(z, nodes)))
71			z++;
72
73	*zone = zonelist_zone(z);
74	return z;
75}
76
77#ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
78int memmap_valid_within(unsigned long pfn,
79					struct page *page, struct zone *zone)
80{
81	if (page_to_pfn(page) != pfn)
82		return 0;
83
84	if (page_zone(page) != zone)
85		return 0;
86
87	return 1;
88}
89#endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */