1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef LINUX_MM_INLINE_H
3 #define LINUX_MM_INLINE_H
4 
5 #include <linux/huge_mm.h>
6 #include <linux/swap.h>
7 
8 /**
9  * page_is_file_cache - should the page be on a file LRU or anon LRU?
10  * @page: the page to test
11  *
12  * Returns 1 if @page is page cache page backed by a regular filesystem,
13  * or 0 if @page is anonymous, tmpfs or otherwise ram or swap backed.
14  * Used by functions that manipulate the LRU lists, to sort a page
15  * onto the right LRU list.
16  *
17  * We would like to get this info without a page flag, but the state
18  * needs to survive until the page is last deleted from the LRU, which
19  * could be as far down as __page_cache_release.
20  */
page_is_file_cache(struct page * page)21 static inline int page_is_file_cache(struct page *page)
22 {
23 	return !PageSwapBacked(page);
24 }
25 
__update_lru_size(struct lruvec * lruvec,enum lru_list lru,enum zone_type zid,int nr_pages)26 static __always_inline void __update_lru_size(struct lruvec *lruvec,
27 				enum lru_list lru, enum zone_type zid,
28 				int nr_pages)
29 {
30 	struct pglist_data *pgdat = lruvec_pgdat(lruvec);
31 
32 	__mod_node_page_state(pgdat, NR_LRU_BASE + lru, nr_pages);
33 	__mod_zone_page_state(&pgdat->node_zones[zid],
34 				NR_ZONE_LRU_BASE + lru, nr_pages);
35 }
36 
update_lru_size(struct lruvec * lruvec,enum lru_list lru,enum zone_type zid,int nr_pages)37 static __always_inline void update_lru_size(struct lruvec *lruvec,
38 				enum lru_list lru, enum zone_type zid,
39 				int nr_pages)
40 {
41 	__update_lru_size(lruvec, lru, zid, nr_pages);
42 #ifdef CONFIG_MEMCG
43 	mem_cgroup_update_lru_size(lruvec, lru, zid, nr_pages);
44 #endif
45 }
46 
add_page_to_lru_list(struct page * page,struct lruvec * lruvec,enum lru_list lru)47 static __always_inline void add_page_to_lru_list(struct page *page,
48 				struct lruvec *lruvec, enum lru_list lru)
49 {
50 	update_lru_size(lruvec, lru, page_zonenum(page), hpage_nr_pages(page));
51 	list_add(&page->lru, &lruvec->lists[lru]);
52 }
53 
add_page_to_lru_list_tail(struct page * page,struct lruvec * lruvec,enum lru_list lru)54 static __always_inline void add_page_to_lru_list_tail(struct page *page,
55 				struct lruvec *lruvec, enum lru_list lru)
56 {
57 	update_lru_size(lruvec, lru, page_zonenum(page), hpage_nr_pages(page));
58 	list_add_tail(&page->lru, &lruvec->lists[lru]);
59 }
60 
del_page_from_lru_list(struct page * page,struct lruvec * lruvec,enum lru_list lru)61 static __always_inline void del_page_from_lru_list(struct page *page,
62 				struct lruvec *lruvec, enum lru_list lru)
63 {
64 	list_del(&page->lru);
65 	update_lru_size(lruvec, lru, page_zonenum(page), -hpage_nr_pages(page));
66 }
67 
68 /**
69  * page_lru_base_type - which LRU list type should a page be on?
70  * @page: the page to test
71  *
72  * Used for LRU list index arithmetic.
73  *
74  * Returns the base LRU type - file or anon - @page should be on.
75  */
page_lru_base_type(struct page * page)76 static inline enum lru_list page_lru_base_type(struct page *page)
77 {
78 	if (page_is_file_cache(page))
79 		return LRU_INACTIVE_FILE;
80 	return LRU_INACTIVE_ANON;
81 }
82 
83 /**
84  * page_off_lru - which LRU list was page on? clearing its lru flags.
85  * @page: the page to test
86  *
87  * Returns the LRU list a page was on, as an index into the array of LRU
88  * lists; and clears its Unevictable or Active flags, ready for freeing.
89  */
page_off_lru(struct page * page)90 static __always_inline enum lru_list page_off_lru(struct page *page)
91 {
92 	enum lru_list lru;
93 
94 	if (PageUnevictable(page)) {
95 		__ClearPageUnevictable(page);
96 		lru = LRU_UNEVICTABLE;
97 	} else {
98 		lru = page_lru_base_type(page);
99 		if (PageActive(page)) {
100 			__ClearPageActive(page);
101 			lru += LRU_ACTIVE;
102 		}
103 	}
104 	return lru;
105 }
106 
107 /**
108  * page_lru - which LRU list should a page be on?
109  * @page: the page to test
110  *
111  * Returns the LRU list a page should be on, as an index
112  * into the array of LRU lists.
113  */
page_lru(struct page * page)114 static __always_inline enum lru_list page_lru(struct page *page)
115 {
116 	enum lru_list lru;
117 
118 	if (PageUnevictable(page))
119 		lru = LRU_UNEVICTABLE;
120 	else {
121 		lru = page_lru_base_type(page);
122 		if (PageActive(page))
123 			lru += LRU_ACTIVE;
124 	}
125 	return lru;
126 }
127 
128 #define lru_to_page(head) (list_entry((head)->prev, struct page, lru))
129 
130 #endif
131