1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited 4 */ 5 #ifndef _ARCH_LOONGARCH_LOCAL_H 6 #define _ARCH_LOONGARCH_LOCAL_H 7 8 #include <linux/percpu.h> 9 #include <linux/bitops.h> 10 #include <linux/atomic.h> 11 #include <asm/cmpxchg.h> 12 13 typedef struct { 14 atomic_long_t a; 15 } local_t; 16 17 #define LOCAL_INIT(i) { ATOMIC_LONG_INIT(i) } 18 19 #define local_read(l) atomic_long_read(&(l)->a) 20 #define local_set(l, i) atomic_long_set(&(l)->a, (i)) 21 22 #define local_add(i, l) atomic_long_add((i), (&(l)->a)) 23 #define local_sub(i, l) atomic_long_sub((i), (&(l)->a)) 24 #define local_inc(l) atomic_long_inc(&(l)->a) 25 #define local_dec(l) atomic_long_dec(&(l)->a) 26 27 /* 28 * Same as above, but return the result value 29 */ 30 static inline long local_add_return(long i, local_t *l) 31 { 32 unsigned long result; 33 34 __asm__ __volatile__( 35 " " __AMADD " %1, %2, %0 \n" 36 : "+ZB" (l->a.counter), "=&r" (result) 37 : "r" (i) 38 : "memory"); 39 result = result + i; 40 41 return result; 42 } 43 44 static inline long local_sub_return(long i, local_t *l) 45 { 46 unsigned long result; 47 48 __asm__ __volatile__( 49 " " __AMADD "%1, %2, %0 \n" 50 : "+ZB" (l->a.counter), "=&r" (result) 51 : "r" (-i) 52 : "memory"); 53 54 result = result - i; 55 56 return result; 57 } 58 59 #define local_cmpxchg(l, o, n) \ 60 ((long)cmpxchg_local(&((l)->a.counter), (o), (n))) 61 #define local_xchg(l, n) (atomic_long_xchg((&(l)->a), (n))) 62 63 /** 64 * local_add_unless - add unless the number is a given value 65 * @l: pointer of type local_t 66 * @a: the amount to add to l... 67 * @u: ...unless l is equal to u. 68 * 69 * Atomically adds @a to @l, so long as it was not @u. 70 * Returns non-zero if @l was not @u, and zero otherwise. 71 */ 72 #define local_add_unless(l, a, u) \ 73 ({ \ 74 long c, old; \ 75 c = local_read(l); \ 76 while (c != (u) && (old = local_cmpxchg((l), c, c + (a))) != c) \ 77 c = old; \ 78 c != (u); \ 79 }) 80 #define local_inc_not_zero(l) local_add_unless((l), 1, 0) 81 82 #define local_dec_return(l) local_sub_return(1, (l)) 83 #define local_inc_return(l) local_add_return(1, (l)) 84 85 /* 86 * local_sub_and_test - subtract value from variable and test result 87 * @i: integer value to subtract 88 * @l: pointer of type local_t 89 * 90 * Atomically subtracts @i from @l and returns 91 * true if the result is zero, or false for all 92 * other cases. 93 */ 94 #define local_sub_and_test(i, l) (local_sub_return((i), (l)) == 0) 95 96 /* 97 * local_inc_and_test - increment and test 98 * @l: pointer of type local_t 99 * 100 * Atomically increments @l by 1 101 * and returns true if the result is zero, or false for all 102 * other cases. 103 */ 104 #define local_inc_and_test(l) (local_inc_return(l) == 0) 105 106 /* 107 * local_dec_and_test - decrement by 1 and test 108 * @l: pointer of type local_t 109 * 110 * Atomically decrements @l by 1 and 111 * returns true if the result is 0, or false for all other 112 * cases. 113 */ 114 #define local_dec_and_test(l) (local_sub_return(1, (l)) == 0) 115 116 /* 117 * local_add_negative - add and test if negative 118 * @l: pointer of type local_t 119 * @i: integer value to add 120 * 121 * Atomically adds @i to @l and returns true 122 * if the result is negative, or false when 123 * result is greater than or equal to zero. 124 */ 125 #define local_add_negative(i, l) (local_add_return(i, (l)) < 0) 126 127 /* Use these for per-cpu local_t variables: on some archs they are 128 * much more efficient than these naive implementations. Note they take 129 * a variable, not an address. 130 */ 131 132 #define __local_inc(l) ((l)->a.counter++) 133 #define __local_dec(l) ((l)->a.counter++) 134 #define __local_add(i, l) ((l)->a.counter += (i)) 135 #define __local_sub(i, l) ((l)->a.counter -= (i)) 136 137 #endif /* _ARCH_LOONGARCH_LOCAL_H */ 138