Git Repo - linux.git/blame_incremental

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Commit	Line	Data
	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	* linux/mm/mmzone.c
	4	*
	5	* management codes for pgdats, zones and page flags
	6	*/
	7
	8
	9	#include <linux/stddef.h>
	10	#include <linux/mm.h>
	11	#include <linux/mmzone.h>
	12
	13	struct pglist_data *first_online_pgdat(void)
	14	{
	15	return NODE_DATA(first_online_node);
	16	}
	17
	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	}
	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	}
	45
	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 */
	56	struct zoneref __next_zones_zonelist(struct zoneref z,
	57	enum zone_type highest_zoneidx,
	58	nodemask_t *nodes)
	59	{
	60	/*
	61	* Find the next suitable zone to use for the allocation.
	62	* Only filter based on nodemask if it's set
	63	*/
	64	if (unlikely(nodes == NULL))
	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
	72	return z;
	73	}
	74
	75	#ifdef CONFIG_ARCH_HAS_HOLES_MEMORYMODEL
	76	bool memmap_valid_within(unsigned long pfn,
	77	struct page page, struct zone zone)
	78	{
	79	if (page_to_pfn(page) != pfn)
	80	return false;
	81
	82	if (page_zone(page) != zone)
	83	return false;
	84
	85	return true;
	86	}
	87	#endif /* CONFIG_ARCH_HAS_HOLES_MEMORYMODEL */
	88
	89	void lruvec_init(struct lruvec *lruvec)
	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]);
	97	}
	98
	99	#if defined(CONFIG_NUMA_BALANCING) && !defined(LAST_CPUPID_NOT_IN_PAGE_FLAGS)
	100	int page_cpupid_xchg_last(struct page *page, int cpupid)
	101	{
	102	unsigned long old_flags, flags;
	103	int last_cpupid;
	104
	105	do {
	106	old_flags = flags = page->flags;
	107	last_cpupid = page_cpupid_last(page);
	108
	109	flags &= ~(LAST_CPUPID_MASK << LAST_CPUPID_PGSHIFT);
	110	flags \|= (cpupid & LAST_CPUPID_MASK) << LAST_CPUPID_PGSHIFT;
	111	} while (unlikely(cmpxchg(&page->flags, old_flags, flags) != old_flags));
	112
	113	return last_cpupid;
	114	}
	115	#endif