[linux.git] / mm / mmzone.c

// SPDX-License-Identifier: GPL-2.0
/*
 * linux/mm/mmzone.c
 *
 * management codes for pgdats, zones and page flags
 */


#include <linux/stddef.h>
#include <linux/mm.h>
#include <linux/mmzone.h>

struct pglist_data *first_online_pgdat(void)
{
	return NODE_DATA(first_online_node);
}

struct pglist_data *next_online_pgdat(struct pglist_data *pgdat)
{
	int nid = next_online_node(pgdat->node_id);

	if (nid == MAX_NUMNODES)
		return NULL;
	return NODE_DATA(nid);
}

/*
 * next_zone - helper magic for for_each_zone()
 */
struct zone *next_zone(struct zone *zone)
{
	pg_data_t *pgdat = zone->zone_pgdat;

	if (zone < pgdat->node_zones + MAX_NR_ZONES - 1)
		zone++;
	else {
		pgdat = next_online_pgdat(pgdat);
		if (pgdat)
			zone = pgdat->node_zones;
		else
			zone = NULL;
	}
	return zone;
}

static inline int zref_in_nodemask(struct zoneref *zref, nodemask_t *nodes)
{
#ifdef CONFIG_NUMA
	return node_isset(zonelist_node_idx(zref), *nodes);
#else
	return 1;
#endif /* CONFIG_NUMA */
}

/* Returns the next zone at or below highest_zoneidx in a zonelist */
struct zoneref *__next_zones_zonelist(struct zoneref *z,
					enum zone_type highest_zoneidx,
					nodemask_t *nodes)
{
	/*
	 * Find the next suitable zone to use for the allocation.
	 * Only filter based on nodemask if it's set
	 */
	if (unlikely(nodes == NULL))
		while (zonelist_zone_idx(z) > highest_zoneidx)
			z++;
	else
		while (zonelist_zone_idx(z) > highest_zoneidx ||
				(z->zone && !zref_in_nodemask(z, nodes)))
			z++;

	return z;
}

#ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
bool memmap_valid_within(unsigned long pfn,
					struct page *page, struct zone *zone)
{
	if (page_to_pfn(page) != pfn)
		return false;

	if (page_zone(page) != zone)
		return false;

	return true;
}
#endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */

void lruvec_init(struct lruvec *lruvec)
{
	enum lru_list lru;

	memset(lruvec, 0, sizeof(struct lruvec));

	for_each_lru(lru)
		INIT_LIST_HEAD(&lruvec->lists[lru]);
}

#if defined(CONFIG_NUMA_BALANCING) && !defined(LAST_CPUPID_NOT_IN_PAGE_FLAGS)
int page_cpupid_xchg_last(struct page *page, int cpupid)
{
	unsigned long old_flags, flags;
	int last_cpupid;

	do {
		old_flags = flags = page->flags;
		last_cpupid = page_cpupid_last(page);

		flags &= ~(LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT);
		flags |= (cpupid & LAST_CPUPID_MASK) << LAST_CPUPID_PGSHIFT;
	} while (unlikely(cmpxchg(&page->flags, old_flags, flags) != old_flags));

	return last_cpupid;
}
#endif
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
95144c78 KH	2	/*
	3	* linux/mm/mmzone.c
	4	*
4468b8f1	5	* management codes for pgdats, zones and page flags
95144c78 KH	6	*/
	7
	8
95144c78	9	#include <linux/stddef.h>
eb33575c	10	#include <linux/mm.h>
95144c78	11	#include <linux/mmzone.h>
95144c78 KH	12
	13	struct pglist_data *first_online_pgdat(void)
	14	{
	15	return NODE_DATA(first_online_node);
	16	}
	17
95144c78 KH	18	struct 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	}
95144c78 KH	26
	27	/*
	28	* next_zone - helper magic for for_each_zone()
	29	*/
	30	struct 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	}
95144c78	45
19770b32 MG	46	static 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 */
682a3385	56	struct zoneref __next_zones_zonelist(struct zoneref z,
19770b32	57	enum zone_type highest_zoneidx,
05891fb0	58	nodemask_t *nodes)
19770b32 MG	59	{
	60	/*
	61	* Find the next suitable zone to use for the allocation.
	62	* Only filter based on nodemask if it's set
	63	*/
e57b9d8c	64	if (unlikely(nodes == NULL))
19770b32 MG	65	while (zonelist_zone_idx(z) > highest_zoneidx)
	66	z++;
	67	else
	68	while (zonelist_zone_idx(z) > highest_zoneidx \|\|
	69	(z->zone && !zref_in_nodemask(z, nodes)))
	70	z++;
	71
19770b32 MG	72	return z;
19770b32 MG	73	}
eb33575c MG	74
eb33575c MG	75	#ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
5b80287a	76	bool memmap_valid_within(unsigned long pfn,
eb33575c MG	77	struct page page, struct zone zone)
	78	{
	79	if (page_to_pfn(page) != pfn)
5b80287a	80	return false;
eb33575c MG	81
eb33575c MG	82	if (page_zone(page) != zone)
5b80287a	83	return false;
eb33575c	84
5b80287a	85	return true;
eb33575c MG	86	}
eb33575c MG	87	#endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
7f5e86c2	88
bea8c150	89	void lruvec_init(struct lruvec *lruvec)
7f5e86c2 KK	90	{
	91	enum lru_list lru;
	92
	93	memset(lruvec, 0, sizeof(struct lruvec));
	94
	95	for_each_lru(lru)
	96	INIT_LIST_HEAD(&lruvec->lists[lru]);
7f5e86c2	97	}
4468b8f1	98
90572890 PZ	99	#if defined(CONFIG_NUMA_BALANCING) && !defined(LAST_CPUPID_NOT_IN_PAGE_FLAGS)
90572890 PZ	100	int page_cpupid_xchg_last(struct page *page, int cpupid)
4468b8f1 MG	101	{
4468b8f1 MG	102	unsigned long old_flags, flags;
90572890	103	int last_cpupid;
4468b8f1 MG	104
	105	do {
	106	old_flags = flags = page->flags;
90572890	107	last_cpupid = page_cpupid_last(page);
4468b8f1	108
90572890 PZ	109	flags &= ~(LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT);
90572890 PZ	110	flags \|= (cpupid & LAST_CPUPID_MASK) << LAST_CPUPID_PGSHIFT;
4468b8f1 MG	111	} while (unlikely(cmpxchg(&page->flags, old_flags, flags) != old_flags));
4468b8f1 MG	112
90572890	113	return last_cpupid;
4468b8f1 MG	114	}
4468b8f1 MG	115	#endif