1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_MM_PAGE_IDLE_H
3 #define _LINUX_MM_PAGE_IDLE_H
4 
5 #include <linux/bitops.h>
6 #include <linux/page-flags.h>
7 #include <linux/page_ext.h>
8 
9 #ifdef CONFIG_IDLE_PAGE_TRACKING
10 
11 #ifdef CONFIG_64BIT
page_is_young(struct page * page)12 static inline bool page_is_young(struct page *page)
13 {
14 	return PageYoung(page);
15 }
16 
set_page_young(struct page * page)17 static inline void set_page_young(struct page *page)
18 {
19 	SetPageYoung(page);
20 }
21 
test_and_clear_page_young(struct page * page)22 static inline bool test_and_clear_page_young(struct page *page)
23 {
24 	return TestClearPageYoung(page);
25 }
26 
page_is_idle(struct page * page)27 static inline bool page_is_idle(struct page *page)
28 {
29 	return PageIdle(page);
30 }
31 
set_page_idle(struct page * page)32 static inline void set_page_idle(struct page *page)
33 {
34 	SetPageIdle(page);
35 }
36 
clear_page_idle(struct page * page)37 static inline void clear_page_idle(struct page *page)
38 {
39 	ClearPageIdle(page);
40 }
41 #else /* !CONFIG_64BIT */
42 /*
43  * If there is not enough space to store Idle and Young bits in page flags, use
44  * page ext flags instead.
45  */
46 extern struct page_ext_operations page_idle_ops;
47 
page_is_young(struct page * page)48 static inline bool page_is_young(struct page *page)
49 {
50 	struct page_ext *page_ext = lookup_page_ext(page);
51 
52 	if (unlikely(!page_ext))
53 		return false;
54 
55 	return test_bit(PAGE_EXT_YOUNG, &page_ext->flags);
56 }
57 
set_page_young(struct page * page)58 static inline void set_page_young(struct page *page)
59 {
60 	struct page_ext *page_ext = lookup_page_ext(page);
61 
62 	if (unlikely(!page_ext))
63 		return;
64 
65 	set_bit(PAGE_EXT_YOUNG, &page_ext->flags);
66 }
67 
test_and_clear_page_young(struct page * page)68 static inline bool test_and_clear_page_young(struct page *page)
69 {
70 	struct page_ext *page_ext = lookup_page_ext(page);
71 
72 	if (unlikely(!page_ext))
73 		return false;
74 
75 	return test_and_clear_bit(PAGE_EXT_YOUNG, &page_ext->flags);
76 }
77 
page_is_idle(struct page * page)78 static inline bool page_is_idle(struct page *page)
79 {
80 	struct page_ext *page_ext = lookup_page_ext(page);
81 
82 	if (unlikely(!page_ext))
83 		return false;
84 
85 	return test_bit(PAGE_EXT_IDLE, &page_ext->flags);
86 }
87 
set_page_idle(struct page * page)88 static inline void set_page_idle(struct page *page)
89 {
90 	struct page_ext *page_ext = lookup_page_ext(page);
91 
92 	if (unlikely(!page_ext))
93 		return;
94 
95 	set_bit(PAGE_EXT_IDLE, &page_ext->flags);
96 }
97 
clear_page_idle(struct page * page)98 static inline void clear_page_idle(struct page *page)
99 {
100 	struct page_ext *page_ext = lookup_page_ext(page);
101 
102 	if (unlikely(!page_ext))
103 		return;
104 
105 	clear_bit(PAGE_EXT_IDLE, &page_ext->flags);
106 }
107 #endif /* CONFIG_64BIT */
108 
109 #else /* !CONFIG_IDLE_PAGE_TRACKING */
110 
page_is_young(struct page * page)111 static inline bool page_is_young(struct page *page)
112 {
113 	return false;
114 }
115 
set_page_young(struct page * page)116 static inline void set_page_young(struct page *page)
117 {
118 }
119 
test_and_clear_page_young(struct page * page)120 static inline bool test_and_clear_page_young(struct page *page)
121 {
122 	return false;
123 }
124 
page_is_idle(struct page * page)125 static inline bool page_is_idle(struct page *page)
126 {
127 	return false;
128 }
129 
set_page_idle(struct page * page)130 static inline void set_page_idle(struct page *page)
131 {
132 }
133 
clear_page_idle(struct page * page)134 static inline void clear_page_idle(struct page *page)
135 {
136 }
137 
138 #endif /* CONFIG_IDLE_PAGE_TRACKING */
139 
140 #endif /* _LINUX_MM_PAGE_IDLE_H */
141