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 static inline long local_cmpxchg(local_t *l, long old, long new) 60 { 61 return cmpxchg_local(&l->a.counter, old, new); 62 } 63 64 static inline bool local_try_cmpxchg(local_t *l, long *old, long new) 65 { 66 return try_cmpxchg_local(&l->a.counter, 67 (typeof(l->a.counter) *) old, new); 68 } 69 70 #define local_xchg(l, n) (atomic_long_xchg((&(l)->a), (n))) 71 72 /** 73 * local_add_unless - add unless the number is already a given value 74 * @l: pointer of type local_t 75 * @a: the amount to add to l... 76 * @u: ...unless l is equal to u. 77 * 78 * Atomically adds @a to @l, if @v was not already @u. 79 * Returns true if the addition was done. 80 */ 81 static inline bool 82 local_add_unless(local_t *l, long a, long u) 83 { 84 long c = local_read(l); 85 86 do { 87 if (unlikely(c == u)) 88 return false; 89 } while (!local_try_cmpxchg(l, &c, c + a)); 90 91 return true; 92 } 93 94 #define local_inc_not_zero(l) local_add_unless((l), 1, 0) 95 96 #define local_dec_return(l) local_sub_return(1, (l)) 97 #define local_inc_return(l) local_add_return(1, (l)) 98 99 /* 100 * local_sub_and_test - subtract value from variable and test result 101 * @i: integer value to subtract 102 * @l: pointer of type local_t 103 * 104 * Atomically subtracts @i from @l and returns 105 * true if the result is zero, or false for all 106 * other cases. 107 */ 108 #define local_sub_and_test(i, l) (local_sub_return((i), (l)) == 0) 109 110 /* 111 * local_inc_and_test - increment and test 112 * @l: pointer of type local_t 113 * 114 * Atomically increments @l by 1 115 * and returns true if the result is zero, or false for all 116 * other cases. 117 */ 118 #define local_inc_and_test(l) (local_inc_return(l) == 0) 119 120 /* 121 * local_dec_and_test - decrement by 1 and test 122 * @l: pointer of type local_t 123 * 124 * Atomically decrements @l by 1 and 125 * returns true if the result is 0, or false for all other 126 * cases. 127 */ 128 #define local_dec_and_test(l) (local_sub_return(1, (l)) == 0) 129 130 /* 131 * local_add_negative - add and test if negative 132 * @l: pointer of type local_t 133 * @i: integer value to add 134 * 135 * Atomically adds @i to @l and returns true 136 * if the result is negative, or false when 137 * result is greater than or equal to zero. 138 */ 139 #define local_add_negative(i, l) (local_add_return(i, (l)) < 0) 140 141 /* Use these for per-cpu local_t variables: on some archs they are 142 * much more efficient than these naive implementations. Note they take 143 * a variable, not an address. 144 */ 145 146 #define __local_inc(l) ((l)->a.counter++) 147 #define __local_dec(l) ((l)->a.counter++) 148 #define __local_add(i, l) ((l)->a.counter += (i)) 149 #define __local_sub(i, l) ((l)->a.counter -= (i)) 150 151 #endif /* _ARCH_LOONGARCH_LOCAL_H */ 152