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