1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
|
/* Low-level functions for atomic operations. RISC-V version.
Copyright (C) 2014-2025 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library. If not, see
<https://www.gnu.org/licenses/>. */
#ifndef _LINUX_RISCV_BITS_ATOMIC_H
#define _LINUX_RISCV_BITS_ATOMIC_H 1
#ifdef __riscv_atomic
#include_next <atomic-machine.h>
/* Miscellaneous. */
# define asm_amo(which, ordering, mem, value) ({ \
__atomic_check_size (mem); \
typeof (*mem) __tmp; \
if (sizeof (__tmp) == 4) \
asm volatile (which ".w" ordering "\t%0, %z2, %1" \
: "=r" (__tmp), "+A" (* (mem)) \
: "rJ" (value)); \
else if (sizeof (__tmp) == 8) \
asm volatile (which ".d" ordering "\t%0, %z2, %1" \
: "=r" (__tmp), "+A" (* (mem)) \
: "rJ" (value)); \
else \
abort (); \
__tmp; })
# define atomic_max(mem, value) asm_amo ("amomaxu", ".aq", mem, value)
# define atomic_min(mem, value) asm_amo ("amominu", ".aq", mem, value)
#else /* __riscv_atomic */
# error "ISAs that do not subsume the A extension are not supported"
#endif /* !__riscv_atomic */
/* Execute a PAUSE hint when spinning. */
#define atomic_spin_nop() __asm(".insn i 0x0f, 0, x0, x0, 0x010")
#endif /* bits/atomic.h */
|
