1 /*- 2 * Copyright (c) 2010 Isilon Systems, Inc. 3 * Copyright (c) 2010 iX Systems, Inc. 4 * Copyright (c) 2010 Panasas, Inc. 5 * Copyright (c) 2013-2017 Mellanox Technologies, Ltd. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice unmodified, this list of conditions, and the following 13 * disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 #ifndef _LINUXKPI_ASM_ATOMIC_LONG_H_ 30 #define _LINUXKPI_ASM_ATOMIC_LONG_H_ 31 32 #include <linux/compiler.h> 33 #include <sys/types.h> 34 #include <machine/atomic.h> 35 #define ATOMIC_LONG_INIT(x) { .counter = (x) } 36 37 typedef struct { 38 volatile long counter; 39 } atomic_long_t; 40 41 #define atomic_long_add(i, v) atomic_long_add_return((i), (v)) 42 #define atomic_long_sub(i, v) atomic_long_sub_return((i), (v)) 43 #define atomic_long_inc_return(v) atomic_long_add_return(1, (v)) 44 #define atomic_long_inc_not_zero(v) atomic_long_add_unless((v), 1, 0) 45 46 static inline long 47 atomic_long_add_return(long i, atomic_long_t *v) 48 { 49 return i + atomic_fetchadd_long(&v->counter, i); 50 } 51 52 static inline long 53 atomic_long_sub_return(long i, atomic_long_t *v) 54 { 55 return atomic_fetchadd_long(&v->counter, -i) - i; 56 } 57 58 static inline void 59 atomic_long_set(atomic_long_t *v, long i) 60 { 61 WRITE_ONCE(v->counter, i); 62 } 63 64 static inline long 65 atomic_long_read(atomic_long_t *v) 66 { 67 return READ_ONCE(v->counter); 68 } 69 70 static inline long 71 atomic_long_inc(atomic_long_t *v) 72 { 73 return atomic_fetchadd_long(&v->counter, 1) + 1; 74 } 75 76 static inline long 77 atomic_long_dec(atomic_long_t *v) 78 { 79 return atomic_fetchadd_long(&v->counter, -1) - 1; 80 } 81 82 static inline long 83 atomic_long_xchg(atomic_long_t *v, long val) 84 { 85 return atomic_swap_long(&v->counter, val); 86 } 87 88 static inline long 89 atomic_long_cmpxchg(atomic_long_t *v, long old, long new) 90 { 91 long ret = old; 92 93 for (;;) { 94 if (atomic_fcmpset_long(&v->counter, &ret, new)) 95 break; 96 if (ret != old) 97 break; 98 } 99 return (ret); 100 } 101 102 static inline int 103 atomic_long_add_unless(atomic_long_t *v, long a, long u) 104 { 105 long c = atomic_long_read(v); 106 107 for (;;) { 108 if (unlikely(c == u)) 109 break; 110 if (likely(atomic_fcmpset_long(&v->counter, &c, c + a))) 111 break; 112 } 113 return (c != u); 114 } 115 116 static inline long 117 atomic_long_fetch_add_unless(atomic_long_t *v, long a, long u) 118 { 119 long c = atomic_long_read(v); 120 121 for (;;) { 122 if (unlikely(c == u)) 123 break; 124 if (likely(atomic_fcmpset_long(&v->counter, &c, c + a))) 125 break; 126 } 127 return (c); 128 } 129 130 static inline long 131 atomic_long_dec_and_test(atomic_long_t *v) 132 { 133 long i = atomic_long_add(-1, v); 134 return i == 0 ; 135 } 136 137 #endif /* _LINUXKPI_ASM_ATOMIC_LONG_H_ */ 138