1 /* 2 * Copyright 2009 Intel Corporation 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 21 * IN THE SOFTWARE. 22 * 23 * Authors: 24 * Chris Wilson <chris (at) chris-wilson.co.uk> 25 * 26 */ 27 28 /** 29 * @file xf86atomics.h 30 * 31 * Private definitions for atomic operations 32 */ 33 34 #ifndef LIBDRM_ATOMICS_H 35 #define LIBDRM_ATOMICS_H 36 37 #ifdef HAVE_CONFIG_H 38 #include "config.h" 39 #endif 40 41 #if HAVE_LIBDRM_ATOMIC_PRIMITIVES 42 43 #define HAS_ATOMIC_OPS 1 44 45 typedef struct { 46 int atomic; 47 } atomic_t; 48 49 # define atomic_read(x) ((x)->atomic) 50 # define atomic_set(x, val) ((x)->atomic = (val)) 51 # define atomic_inc(x) ((void) __sync_fetch_and_add (&(x)->atomic, 1)) 52 # define atomic_inc_return(x) (__sync_add_and_fetch (&(x)->atomic, 1)) 53 # define atomic_dec_and_test(x) (__sync_add_and_fetch (&(x)->atomic, -1) == 0) 54 # define atomic_add(x, v) ((void) __sync_add_and_fetch(&(x)->atomic, (v))) 55 # define atomic_dec(x, v) ((void) __sync_sub_and_fetch(&(x)->atomic, (v))) 56 # define atomic_cmpxchg(x, oldv, newv) __sync_val_compare_and_swap (&(x)->atomic, oldv, newv) 57 58 #endif 59 60 #if HAVE_LIB_ATOMIC_OPS 61 #include <atomic_ops.h> 62 63 #define HAS_ATOMIC_OPS 1 64 65 typedef struct { 66 AO_t atomic; 67 } atomic_t; 68 69 # define atomic_read(x) AO_load_full(&(x)->atomic) 70 # define atomic_set(x, val) AO_store_full(&(x)->atomic, (val)) 71 # define atomic_inc(x) ((void) AO_fetch_and_add1_full(&(x)->atomic)) 72 # define atomic_inc_return(x) (AO_fetch_and_add1_full(&(x)->atomic) + 1) 73 # define atomic_add(x, v) ((void) AO_fetch_and_add_full(&(x)->atomic, (v))) 74 # define atomic_dec(x, v) ((void) AO_fetch_and_add_full(&(x)->atomic, -(v))) 75 # define atomic_dec_and_test(x) (AO_fetch_and_sub1_full(&(x)->atomic) == 1) 76 # define atomic_cmpxchg(x, oldv, newv) AO_compare_and_swap_full(&(x)->atomic, oldv, newv) 77 78 #endif 79 80 #if (defined(__sun) || defined(__NetBSD__)) && !defined(HAS_ATOMIC_OPS) /* Solaris & OpenSolaris & NetBSD */ 81 82 #include <sys/atomic.h> 83 #define HAS_ATOMIC_OPS 1 84 85 #if defined(__NetBSD__) 86 #define LIBDRM_ATOMIC_TYPE int 87 #else 88 #define LIBDRM_ATOMIC_TYPE uint_t 89 #endif 90 91 typedef struct { LIBDRM_ATOMIC_TYPE atomic; } atomic_t; 92 93 # define atomic_read(x) (int) ((x)->atomic) 94 # define atomic_set(x, val) ((x)->atomic = (LIBDRM_ATOMIC_TYPE)(val)) 95 # define atomic_inc(x) (atomic_inc_uint (&(x)->atomic)) 96 # define atomic_inc_return(x) (atomic_inc_uint_nv(&(x)->atomic)) 97 # define atomic_dec_and_test(x) (atomic_dec_uint_nv(&(x)->atomic) == 0) 98 # define atomic_add(x, v) (atomic_add_int(&(x)->atomic, (v))) 99 # define atomic_dec(x, v) (atomic_add_int(&(x)->atomic, -(v))) 100 # define atomic_cmpxchg(x, oldv, newv) atomic_cas_uint (&(x)->atomic, oldv, newv) 101 102 #endif 103 104 #if ! HAS_ATOMIC_OPS 105 #error libdrm requires atomic operations, please define them for your CPU/compiler. 106 #endif 107 108 static inline int atomic_add_unless(atomic_t *v, int add, int unless) 109 { 110 int c, old; 111 c = atomic_read(v); 112 while (c != unless && (old = atomic_cmpxchg(v, c, c + add)) != c) 113 c = old; 114 return c == unless; 115 } 116 117 #endif 118