xref: /linux-6.15/include/linux/pgalloc_tag.h (revision dfd19866)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * page allocation tagging
4  */
5 #ifndef _LINUX_PGALLOC_TAG_H
6 #define _LINUX_PGALLOC_TAG_H
7 
8 #include <linux/alloc_tag.h>
9 
10 #ifdef CONFIG_MEM_ALLOC_PROFILING
11 
12 #include <linux/page_ext.h>
13 
14 extern struct page_ext_operations page_alloc_tagging_ops;
15 
16 static inline union codetag_ref *codetag_ref_from_page_ext(struct page_ext *page_ext)
17 {
18 	return (void *)page_ext + page_alloc_tagging_ops.offset;
19 }
20 
21 static inline struct page_ext *page_ext_from_codetag_ref(union codetag_ref *ref)
22 {
23 	return (void *)ref - page_alloc_tagging_ops.offset;
24 }
25 
26 /* Should be called only if mem_alloc_profiling_enabled() */
27 static inline union codetag_ref *get_page_tag_ref(struct page *page)
28 {
29 	if (page) {
30 		struct page_ext *page_ext = page_ext_get(page);
31 
32 		if (page_ext)
33 			return codetag_ref_from_page_ext(page_ext);
34 	}
35 	return NULL;
36 }
37 
38 static inline void put_page_tag_ref(union codetag_ref *ref)
39 {
40 	if (WARN_ON(!ref))
41 		return;
42 
43 	page_ext_put(page_ext_from_codetag_ref(ref));
44 }
45 
46 static inline void pgalloc_tag_add(struct page *page, struct task_struct *task,
47 				   unsigned int nr)
48 {
49 	if (mem_alloc_profiling_enabled()) {
50 		union codetag_ref *ref = get_page_tag_ref(page);
51 
52 		if (ref) {
53 			alloc_tag_add(ref, task->alloc_tag, PAGE_SIZE * nr);
54 			put_page_tag_ref(ref);
55 		}
56 	}
57 }
58 
59 static inline void pgalloc_tag_sub(struct page *page, unsigned int nr)
60 {
61 	if (mem_alloc_profiling_enabled()) {
62 		union codetag_ref *ref = get_page_tag_ref(page);
63 
64 		if (ref) {
65 			alloc_tag_sub(ref, PAGE_SIZE * nr);
66 			put_page_tag_ref(ref);
67 		}
68 	}
69 }
70 
71 static inline void pgalloc_tag_split(struct page *page, unsigned int nr)
72 {
73 	int i;
74 	struct page_ext *page_ext;
75 	union codetag_ref *ref;
76 	struct alloc_tag *tag;
77 
78 	if (!mem_alloc_profiling_enabled())
79 		return;
80 
81 	page_ext = page_ext_get(page);
82 	if (unlikely(!page_ext))
83 		return;
84 
85 	ref = codetag_ref_from_page_ext(page_ext);
86 	if (!ref->ct)
87 		goto out;
88 
89 	tag = ct_to_alloc_tag(ref->ct);
90 	page_ext = page_ext_next(page_ext);
91 	for (i = 1; i < nr; i++) {
92 		/* Set new reference to point to the original tag */
93 		alloc_tag_ref_set(codetag_ref_from_page_ext(page_ext), tag);
94 		page_ext = page_ext_next(page_ext);
95 	}
96 out:
97 	page_ext_put(page_ext);
98 }
99 
100 static inline struct alloc_tag *pgalloc_tag_get(struct page *page)
101 {
102 	struct alloc_tag *tag = NULL;
103 
104 	if (mem_alloc_profiling_enabled()) {
105 		union codetag_ref *ref = get_page_tag_ref(page);
106 
107 		alloc_tag_sub_check(ref);
108 		if (ref) {
109 			if (ref->ct)
110 				tag = ct_to_alloc_tag(ref->ct);
111 			put_page_tag_ref(ref);
112 		}
113 	}
114 
115 	return tag;
116 }
117 
118 static inline void pgalloc_tag_sub_pages(struct alloc_tag *tag, unsigned int nr)
119 {
120 	if (mem_alloc_profiling_enabled() && tag)
121 		this_cpu_sub(tag->counters->bytes, PAGE_SIZE * nr);
122 }
123 
124 #else /* CONFIG_MEM_ALLOC_PROFILING */
125 
126 static inline union codetag_ref *get_page_tag_ref(struct page *page) { return NULL; }
127 static inline void put_page_tag_ref(union codetag_ref *ref) {}
128 static inline void pgalloc_tag_add(struct page *page, struct task_struct *task,
129 				   unsigned int nr) {}
130 static inline void pgalloc_tag_sub(struct page *page, unsigned int nr) {}
131 static inline void pgalloc_tag_split(struct page *page, unsigned int nr) {}
132 static inline struct alloc_tag *pgalloc_tag_get(struct page *page) { return NULL; }
133 static inline void pgalloc_tag_sub_pages(struct alloc_tag *tag, unsigned int nr) {}
134 
135 #endif /* CONFIG_MEM_ALLOC_PROFILING */
136 
137 #endif /* _LINUX_PGALLOC_TAG_H */
138