xref: /openbmc/linux/mm/shuffle.h (revision 8f762fe5)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright(c) 2018 Intel Corporation. All rights reserved.
3 #ifndef _MM_SHUFFLE_H
4 #define _MM_SHUFFLE_H
5 #include <linux/jump_label.h>
6 
7 /*
8  * SHUFFLE_ENABLE is called from the command line enabling path, or by
9  * platform-firmware enabling that indicates the presence of a
10  * direct-mapped memory-side-cache. SHUFFLE_FORCE_DISABLE is called from
11  * the command line path and overrides any previous or future
12  * SHUFFLE_ENABLE.
13  */
14 enum mm_shuffle_ctl {
15 	SHUFFLE_ENABLE,
16 	SHUFFLE_FORCE_DISABLE,
17 };
18 
19 #define SHUFFLE_ORDER (MAX_ORDER-1)
20 
21 #ifdef CONFIG_SHUFFLE_PAGE_ALLOCATOR
22 DECLARE_STATIC_KEY_FALSE(page_alloc_shuffle_key);
23 extern void page_alloc_shuffle(enum mm_shuffle_ctl ctl);
24 extern void __shuffle_free_memory(pg_data_t *pgdat);
25 static inline void shuffle_free_memory(pg_data_t *pgdat)
26 {
27 	if (!static_branch_unlikely(&page_alloc_shuffle_key))
28 		return;
29 	__shuffle_free_memory(pgdat);
30 }
31 
32 extern void __shuffle_zone(struct zone *z);
33 static inline void shuffle_zone(struct zone *z)
34 {
35 	if (!static_branch_unlikely(&page_alloc_shuffle_key))
36 		return;
37 	__shuffle_zone(z);
38 }
39 
40 static inline bool is_shuffle_order(int order)
41 {
42 	if (!static_branch_unlikely(&page_alloc_shuffle_key))
43 		return false;
44 	return order >= SHUFFLE_ORDER;
45 }
46 #else
47 static inline void shuffle_free_memory(pg_data_t *pgdat)
48 {
49 }
50 
51 static inline void shuffle_zone(struct zone *z)
52 {
53 }
54 
55 static inline void page_alloc_shuffle(enum mm_shuffle_ctl ctl)
56 {
57 }
58 
59 static inline bool is_shuffle_order(int order)
60 {
61 	return false;
62 }
63 #endif
64 #endif /* _MM_SHUFFLE_H */
65