1 /* 2 * Based on arch/arm/include/asm/atomic.h 3 * 4 * Copyright (C) 1996 Russell King. 5 * Copyright (C) 2002 Deep Blue Solutions Ltd. 6 * Copyright (C) 2012 ARM Ltd. 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License version 2 as 10 * published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program. If not, see <http://www.gnu.org/licenses/>. 19 */ 20 #ifndef __ASM_ATOMIC_H 21 #define __ASM_ATOMIC_H 22 23 #include <linux/compiler.h> 24 #include <linux/types.h> 25 26 #include <asm/barrier.h> 27 #include <asm/lse.h> 28 29 #ifdef __KERNEL__ 30 31 #define __ARM64_IN_ATOMIC_IMPL 32 33 #if defined(CONFIG_ARM64_LSE_ATOMICS) && defined(CONFIG_AS_LSE) 34 #include <asm/atomic_lse.h> 35 #else 36 #include <asm/atomic_ll_sc.h> 37 #endif 38 39 #undef __ARM64_IN_ATOMIC_IMPL 40 41 #include <asm/cmpxchg.h> 42 43 #define ___atomic_add_unless(v, a, u, sfx) \ 44 ({ \ 45 typeof((v)->counter) c, old; \ 46 \ 47 c = atomic##sfx##_read(v); \ 48 while (c != (u) && \ 49 (old = atomic##sfx##_cmpxchg((v), c, c + (a))) != c) \ 50 c = old; \ 51 c; \ 52 }) 53 54 #define ATOMIC_INIT(i) { (i) } 55 56 #define atomic_read(v) READ_ONCE((v)->counter) 57 #define atomic_set(v, i) (((v)->counter) = (i)) 58 #define atomic_xchg(v, new) xchg(&((v)->counter), (new)) 59 #define atomic_cmpxchg(v, old, new) cmpxchg(&((v)->counter), (old), (new)) 60 61 #define atomic_inc(v) atomic_add(1, (v)) 62 #define atomic_dec(v) atomic_sub(1, (v)) 63 #define atomic_inc_return(v) atomic_add_return(1, (v)) 64 #define atomic_dec_return(v) atomic_sub_return(1, (v)) 65 #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0) 66 #define atomic_dec_and_test(v) (atomic_dec_return(v) == 0) 67 #define atomic_sub_and_test(i, v) (atomic_sub_return((i), (v)) == 0) 68 #define atomic_add_negative(i, v) (atomic_add_return((i), (v)) < 0) 69 #define __atomic_add_unless(v, a, u) ___atomic_add_unless(v, a, u,) 70 #define atomic_andnot atomic_andnot 71 72 /* 73 * 64-bit atomic operations. 74 */ 75 #define ATOMIC64_INIT ATOMIC_INIT 76 #define atomic64_read atomic_read 77 #define atomic64_set atomic_set 78 #define atomic64_xchg atomic_xchg 79 #define atomic64_cmpxchg atomic_cmpxchg 80 81 #define atomic64_inc(v) atomic64_add(1, (v)) 82 #define atomic64_dec(v) atomic64_sub(1, (v)) 83 #define atomic64_inc_return(v) atomic64_add_return(1, (v)) 84 #define atomic64_dec_return(v) atomic64_sub_return(1, (v)) 85 #define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0) 86 #define atomic64_dec_and_test(v) (atomic64_dec_return(v) == 0) 87 #define atomic64_sub_and_test(i, v) (atomic64_sub_return((i), (v)) == 0) 88 #define atomic64_add_negative(i, v) (atomic64_add_return((i), (v)) < 0) 89 #define atomic64_add_unless(v, a, u) (___atomic_add_unless(v, a, u, 64) != u) 90 #define atomic64_andnot atomic64_andnot 91 92 #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0) 93 94 #endif 95 #endif 96