129 	NUMA_INTERLEAVE_HIT,	/* interleaver preferred this zone */
702  * zone lock contention and keep cache-hot pages reusing.
791 	 *    faulted, they come from the right zone right away. However, it is
795 	 *    to a different zone. When migration fails - pinning fails.
816 	 *    on different platforms may end up in a movable zone. ZERO_PAGE(0)
819 	 *    memory to the MOVABLE zone, the vmemmap pages are also placed in
820 	 *    such zone. Such pages cannot be really moved around as they are
842 struct zone {  struct
845 	/* zone watermarks, access with *_wmark_pages(zone) macros */
855 	 * wasting several GB of ram we must reserve some of the lower zone  argument
889 	 * spanned_pages is the total pages spanned by the zone, including  argument
893 	 * present_pages is physical pages existing within the zone, which
897 	 * present_early_pages is present pages existing within the zone
918 	 * It is a seqlock because it has to be read outside of zone->lock,
922 	 * The span_seq lock is declared along with zone->lock because it is
923 	 * frequently read in proximity to zone->lock.  It's good to
946 	 * of pageblock. Protected by zone->lock.  argument
969 	/* zone flags, see below */  argument
1014 	/* Zone statistics */
1031 	ZONE_BOOSTED_WATERMARK,		/* zone recently boosted watermarks.  argument
1034 	ZONE_RECLAIM_ACTIVE,		/* kswapd may be scanning the zone. */
1035 	ZONE_BELOW_HIGH,		/* zone is below high watermark. */
1038 static inline unsigned long wmark_pages(const struct zone *z,  in wmark_pages()
1044 static inline unsigned long min_wmark_pages(const struct zone *z)  in min_wmark_pages()
1049 static inline unsigned long low_wmark_pages(const struct zone *z)  in low_wmark_pages()
1054 static inline unsigned long high_wmark_pages(const struct zone *z)  in high_wmark_pages()
1059 static inline unsigned long promo_wmark_pages(const struct zone *z)  in promo_wmark_pages()
1064 static inline unsigned long zone_managed_pages(struct zone *zone)  in zone_managed_pages()  argument
1066 	return (unsigned long)atomic_long_read(&zone->managed_pages);  in zone_managed_pages()
1069 static inline unsigned long zone_cma_pages(struct zone *zone)  in zone_cma_pages()  argument
1072 	return zone->cma_pages;  in zone_cma_pages()
1078 static inline unsigned long zone_end_pfn(const struct zone *zone)  in zone_end_pfn()  argument
1080 	return zone->zone_start_pfn + zone->spanned_pages;  in zone_end_pfn()
1083 static inline bool zone_spans_pfn(const struct zone *zone, unsigned long pfn)  in zone_spans_pfn()  argument
1085 	return zone->zone_start_pfn <= pfn && pfn < zone_end_pfn(zone);  in zone_spans_pfn()
1088 static inline bool zone_is_initialized(struct zone *zone)  in zone_is_initialized()  argument
1090 	return zone->initialized;  in zone_is_initialized()
1093 static inline bool zone_is_empty(struct zone *zone)  in zone_is_empty()  argument
1095 	return zone->spanned_pages == 0;  in zone_is_empty()
1100  * The zone field is never updated after free_area_init_core()
1104 /* Page flags: | [SECTION] | [NODE] | ZONE | [LAST_CPUPID] | ... | FLAGS | */
1124 /* NODE:ZONE or SECTION:ZONE is used to ID a zone for the buddy allocator */
1162  * Consecutive zone device pages should not be merged into the same sgl
1166  * both pages are not zone device pages or both pages are zone device pages
1179 extern void memmap_init_zone_device(struct zone *, unsigned long,
1211  * intersection with the given zone
1213 static inline bool zone_intersects(struct zone *zone,  in zone_intersects()  argument
1216 	if (zone_is_empty(zone))  in zone_intersects()
1218 	if (start_pfn >= zone_end_pfn(zone) ||  in zone_intersects()
1219 	    start_pfn + nr_pages <= zone->zone_start_pfn)  in zone_intersects()
1248  * This struct contains information about a zone in a zonelist. It is stored
1252 	struct zone *zone;	/* Pointer to actual zone */  member
1253 	int zone_idx;		/* zone_idx(zoneref->zone) */
1262  * To speed the reading of the zonelist, the zonerefs contain the zone index
1266  * zonelist_zone()	- Return the struct zone * for an entry in _zonerefs
1267  * zonelist_zone_idx()	- Return the index of the zone for an entry
1320  * per-zone basis.
1328 	struct zone node_zones[MAX_NR_ZONES];
1355 	 * Nests above zone->lock and zone->span_seqlock
1478 void wakeup_kswapd(struct zone *zone, gfp_t gfp_mask, int order,
1480 bool __zone_watermark_ok(struct zone *z, unsigned int order, unsigned long mark,
1483 bool zone_watermark_ok(struct zone *z, unsigned int order,
1486 bool zone_watermark_ok_safe(struct zone *z, unsigned int order,
1497 extern void init_currently_empty_zone(struct zone *zone, unsigned long start_pfn,
1518  * zone_idx() returns 0 for the ZONE_DMA zone, 1 for the ZONE_NORMAL zone, etc.
1520 #define zone_idx(zone)		((zone) - (zone)->zone_pgdat->node_zones)  argument
1523 static inline bool zone_is_zone_device(struct zone *zone)  in zone_is_zone_device()  argument
1525 	return zone_idx(zone) == ZONE_DEVICE;  in zone_is_zone_device()
1528 static inline bool zone_is_zone_device(struct zone *zone)  in zone_is_zone_device()  argument
1535  * Returns true if a zone has pages managed by the buddy allocator.
1537  * populated_zone(). If the whole zone is reserved then we can easily
1540 static inline bool managed_zone(struct zone *zone)  in managed_zone()  argument
1542 	return zone_managed_pages(zone);  in managed_zone()
1545 /* Returns true if a zone has memory */
1546 static inline bool populated_zone(struct zone *zone)  in populated_zone()  argument
1548 	return zone->present_pages;  in populated_zone()
1552 static inline int zone_to_nid(struct zone *zone)  in zone_to_nid()  argument
1554 	return zone->node;  in zone_to_nid()
1557 static inline void zone_set_nid(struct zone *zone, int nid)  in zone_set_nid()  argument
1559 	zone->node = nid;  in zone_set_nid()
1562 static inline int zone_to_nid(struct zone *zone)  in zone_to_nid()  argument
1567 static inline void zone_set_nid(struct zone *zone, int nid) {}  in zone_set_nid()  argument
1583  * is_highmem - helper function to quickly check if a struct zone is a
1584  *              highmem zone or not.  This is an attempt to keep references
1586  * @zone: pointer to struct zone variable
1587  * Return: 1 for a highmem zone, 0 otherwise
1589 static inline int is_highmem(struct zone *zone)  in is_highmem()  argument
1591 	return is_highmem_idx(zone_idx(zone));  in is_highmem()
1620 extern struct zone *next_zone(struct zone *zone);
1632  * @zone: pointer to struct zone variable
1634  * The user only needs to declare the zone variable, for_each_zone
1637 #define for_each_zone(zone)			        \  argument
1638 	for (zone = (first_online_pgdat())->node_zones; \
1639 	     zone;					\
1640 	     zone = next_zone(zone))
1642 #define for_each_populated_zone(zone)		        \  argument
1643 	for (zone = (first_online_pgdat())->node_zones; \
1644 	     zone;					\
1645 	     zone = next_zone(zone))			\
1646 		if (!populated_zone(zone))		\
1650 static inline struct zone *zonelist_zone(struct zoneref *zoneref)  in zonelist_zone()
1652 	return zoneref->zone;  in zonelist_zone()
1662 	return zone_to_nid(zoneref->zone);  in zonelist_node_idx()
1670 …* next_zones_zonelist - Returns the next zone at or below highest_zoneidx within the allowed nodem…
1672  * @highest_zoneidx: The zone index of the highest zone to return
1675  * This function returns the next zone at or below a given zone index that is
1677  * search. The zoneref returned is a cursor that represents the current zone
1681  * Return: the next zone at or below highest_zoneidx within the allowed
1694 …* first_zones_zonelist - Returns the first zone at or below highest_zoneidx within the allowed nod…
1695  * @zonelist: The zonelist to search for a suitable zone
1696  * @highest_zoneidx: The zone index of the highest zone to return
1699  * This function returns the first zone at or below a given zone index that is
1704  * When no eligible zone is found, zoneref->zone is NULL (zoneref itself is
1708  * Return: Zoneref pointer for the first suitable zone found
1719 …elper macro to iterate over valid zones in a zonelist at or below a given zone index and within a …
1720  * @zone: The current zone in the iterator
1723  * @highidx: The zone index of the highest zone to return
1726  * This iterator iterates though all zones at or below a given zone index and
1729 #define for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, nodemask) \  argument
1730 	for (z = first_zones_zonelist(zlist, highidx, nodemask), zone = zonelist_zone(z);	\
1731 		zone;							\
1733 			zone = zonelist_zone(z))
1735 #define for_next_zone_zonelist_nodemask(zone, z, highidx, nodemask) \  argument
1736 	for (zone = zonelist_zone(z);	\
1737 		zone;							\
1739 			zone = zonelist_zone(z))
1743 …ne_zonelist - helper macro to iterate over valid zones in a zonelist at or below a given zone index
1744  * @zone: The current zone in the iterator
1747  * @highidx: The zone index of the highest zone to return
1749  * This iterator iterates though all zones at or below a given zone index.
1751 #define for_each_zone_zonelist(zone, z, zlist, highidx) \  argument
1752 	for_each_zone_zonelist_nodemask(zone, z, zlist, highidx, NULL)
1767 	 * at least one zone that can satisfy kernel allocations.  in movable_only_nodes()
1838 	/* See declaration of similar field in struct zone */