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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _TOOLS_LINUX_ASM_AARCH64_BARRIER_H
3#define _TOOLS_LINUX_ASM_AARCH64_BARRIER_H
4
5/*
6 * From tools/perf/perf-sys.h, last modified in:
7 * f428ebd184c82a7914b2aa7e9f868918aaf7ea78 perf tools: Fix AAAAARGH64 memory barriers
8 *
9 * XXX: arch/arm64/include/asm/barrier.h in the kernel sources use dsb, is this
10 * a case like for arm32 where we do things differently in userspace?
11 */
12
13#define mb() asm volatile("dmb ish" ::: "memory")
14#define wmb() asm volatile("dmb ishst" ::: "memory")
15#define rmb() asm volatile("dmb ishld" ::: "memory")
16
17#define smp_store_release(p, v) \
18do { \
19 union { typeof(*p) __val; char __c[1]; } __u = \
20 { .__val = (v) }; \
21 \
22 switch (sizeof(*p)) { \
23 case 1: \
24 asm volatile ("stlrb %w1, %0" \
25 : "=Q" (*p) \
26 : "r" (*(__u8_alias_t *)__u.__c) \
27 : "memory"); \
28 break; \
29 case 2: \
30 asm volatile ("stlrh %w1, %0" \
31 : "=Q" (*p) \
32 : "r" (*(__u16_alias_t *)__u.__c) \
33 : "memory"); \
34 break; \
35 case 4: \
36 asm volatile ("stlr %w1, %0" \
37 : "=Q" (*p) \
38 : "r" (*(__u32_alias_t *)__u.__c) \
39 : "memory"); \
40 break; \
41 case 8: \
42 asm volatile ("stlr %1, %0" \
43 : "=Q" (*p) \
44 : "r" (*(__u64_alias_t *)__u.__c) \
45 : "memory"); \
46 break; \
47 default: \
48 /* Only to shut up gcc ... */ \
49 mb(); \
50 break; \
51 } \
52} while (0)
53
54#define smp_load_acquire(p) \
55({ \
56 union { typeof(*p) __val; char __c[1]; } __u = \
57 { .__c = { 0 } }; \
58 \
59 switch (sizeof(*p)) { \
60 case 1: \
61 asm volatile ("ldarb %w0, %1" \
62 : "=r" (*(__u8_alias_t *)__u.__c) \
63 : "Q" (*p) : "memory"); \
64 break; \
65 case 2: \
66 asm volatile ("ldarh %w0, %1" \
67 : "=r" (*(__u16_alias_t *)__u.__c) \
68 : "Q" (*p) : "memory"); \
69 break; \
70 case 4: \
71 asm volatile ("ldar %w0, %1" \
72 : "=r" (*(__u32_alias_t *)__u.__c) \
73 : "Q" (*p) : "memory"); \
74 break; \
75 case 8: \
76 asm volatile ("ldar %0, %1" \
77 : "=r" (*(__u64_alias_t *)__u.__c) \
78 : "Q" (*p) : "memory"); \
79 break; \
80 default: \
81 /* Only to shut up gcc ... */ \
82 mb(); \
83 break; \
84 } \
85 __u.__val; \
86})
87
88#endif /* _TOOLS_LINUX_ASM_AARCH64_BARRIER_H */