xref: /openbmc/linux/mm/shuffle.h (revision 37744fee)
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 extern bool shuffle_pick_tail(void);
26 static inline void shuffle_free_memory(pg_data_t *pgdat)
27 {
28 	if (!static_branch_unlikely(&page_alloc_shuffle_key))
29 		return;
30 	__shuffle_free_memory(pgdat);
31 }
32 
33 extern void __shuffle_zone(struct zone *z);
34 static inline void shuffle_zone(struct zone *z)
35 {
36 	if (!static_branch_unlikely(&page_alloc_shuffle_key))
37 		return;
38 	__shuffle_zone(z);
39 }
40 
41 static inline bool is_shuffle_order(int order)
42 {
43 	if (!static_branch_unlikely(&page_alloc_shuffle_key))
44 		return false;
45 	return order >= SHUFFLE_ORDER;
46 }
47 #else
48 static inline bool shuffle_pick_tail(void)
49 {
50 	return false;
51 }
52 
53 static inline void shuffle_free_memory(pg_data_t *pgdat)
54 {
55 }
56 
57 static inline void shuffle_zone(struct zone *z)
58 {
59 }
60 
61 static inline void page_alloc_shuffle(enum mm_shuffle_ctl ctl)
62 {
63 }
64 
65 static inline bool is_shuffle_order(int order)
66 {
67 	return false;
68 }
69 #endif
70 #endif /* _MM_SHUFFLE_H */
71