4 * management codes for pgdats, zones and page flags
8 #include <linux/stddef.h>
10 #include <linux/mmzone.h>
12 struct pglist_data *first_online_pgdat(void)
14 return NODE_DATA(first_online_node);
17 struct pglist_data *next_online_pgdat(struct pglist_data *pgdat)
19 int nid = next_online_node(pgdat->node_id);
21 if (nid == MAX_NUMNODES)
23 return NODE_DATA(nid);
27 * next_zone - helper magic for for_each_zone()
29 struct zone *next_zone(struct zone *zone)
31 pg_data_t *pgdat = zone->zone_pgdat;
33 if (zone < pgdat->node_zones + MAX_NR_ZONES - 1)
36 pgdat = next_online_pgdat(pgdat);
38 zone = pgdat->node_zones;
45 static inline int zref_in_nodemask(struct zoneref *zref, nodemask_t *nodes)
48 return node_isset(zonelist_node_idx(zref), *nodes);
51 #endif /* CONFIG_NUMA */
54 /* Returns the next zone at or below highest_zoneidx in a zonelist */
55 struct zoneref *next_zones_zonelist(struct zoneref *z,
56 enum zone_type highest_zoneidx,
60 * Find the next suitable zone to use for the allocation.
61 * Only filter based on nodemask if it's set
63 if (likely(nodes == NULL))
64 while (zonelist_zone_idx(z) > highest_zoneidx)
67 while (zonelist_zone_idx(z) > highest_zoneidx ||
68 (z->zone && !zref_in_nodemask(z, nodes)))
74 #ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
75 int memmap_valid_within(unsigned long pfn,
76 struct page *page, struct zone *zone)
78 if (page_to_pfn(page) != pfn)
81 if (page_zone(page) != zone)
86 #endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
88 void lruvec_init(struct lruvec *lruvec)
92 memset(lruvec, 0, sizeof(struct lruvec));
95 INIT_LIST_HEAD(&lruvec->lists[lru]);
98 #if defined(CONFIG_NUMA_BALANCING) && !defined(LAST_CPUPID_NOT_IN_PAGE_FLAGS)
99 int page_cpupid_xchg_last(struct page *page, int cpupid)
101 unsigned long old_flags, flags;
105 old_flags = flags = page->flags;
106 last_cpupid = page_cpupid_last(page);
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));