xref: /titanic_44/usr/src/uts/intel/asm/atomic.h (revision 1a5e258f5471356ca102c7176637cdce45bac147)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  * Copyright 2014 Nexenta Systems, Inc.  All rights reserved.
26  */
27 
28 #ifndef _ASM_ATOMIC_H
29 #define	_ASM_ATOMIC_H
30 
31 #include <sys/ccompile.h>
32 #include <sys/types.h>
33 
34 #ifdef	__cplusplus
35 extern "C" {
36 #endif
37 
38 #if !defined(__lint) && defined(__GNUC__)
39 
40 /* BEGIN CSTYLED */
41 /*
42  * This file contains a number of static inline functions implementing
43  * various atomic variable functions.  Note that these are *not* all of the
44  * atomic_* functions as defined in usr/src/uts/common/sys/atomic.h.  All
45  * possible atomic_* functions are implemented in usr/src/common/atomic in
46  * pure assembly.  In the absence of an identically named function in this
47  * header file, any use of the function will result in the compiler emitting
48  * a function call as usual.  On the other hand, if an identically named
49  * function exists in this header as a static inline, the compiler will
50  * inline its contents and the linker never sees the symbol reference.  We
51  * use this to avoid implementing some of the more complex and less used
52  * functions and instead falling back to function calls.  Note that in some
53  * cases (e.g., atomic_inc_64) we implement a static inline only on AMD64
54  * but not i386.
55  */
56 
57 /*
58  * Instruction suffixes for various operand sizes (assuming AMD64)
59  */
60 #define	SUF_8		"b"
61 #define	SUF_16		"w"
62 #define	SUF_32		"l"
63 #define	SUF_64		"q"
64 
65 #if defined(__amd64)
66 #define	SUF_LONG	SUF_64
67 #define	SUF_PTR		SUF_64
68 #define	__ATOMIC_OP64(...)	__ATOMIC_OPXX(__VA_ARGS__)
69 #elif defined(__i386)
70 #define	SUF_LONG	SUF_32
71 #define	SUF_PTR		SUF_32
72 #define	__ATOMIC_OP64(...)
73 #else
74 #error "port me"
75 #endif
76 
77 #if defined(__amd64) || defined(__i386)
78 
79 #define	__ATOMIC_OPXX(fxn, type, op)					\
80 extern __GNU_INLINE void						\
81 fxn(volatile type *target)						\
82 {									\
83 	__asm__ __volatile__(						\
84 	    "lock; " op " %0"						\
85 	    : "+m" (*target));						\
86 }
87 
88 __ATOMIC_OPXX(atomic_inc_8,      uint8_t,  "inc" SUF_8)
89 __ATOMIC_OPXX(atomic_inc_16,     uint16_t, "inc" SUF_16)
90 __ATOMIC_OPXX(atomic_inc_32,     uint32_t, "inc" SUF_32)
91 __ATOMIC_OP64(atomic_inc_64,     uint64_t, "inc" SUF_64)
92 __ATOMIC_OPXX(atomic_inc_uchar,  uchar_t,  "inc" SUF_8)
93 __ATOMIC_OPXX(atomic_inc_ushort, ushort_t, "inc" SUF_16)
94 __ATOMIC_OPXX(atomic_inc_uint,   uint_t,   "inc" SUF_32)
95 __ATOMIC_OPXX(atomic_inc_ulong,  ulong_t,  "inc" SUF_LONG)
96 
97 __ATOMIC_OPXX(atomic_dec_8,      uint8_t,  "dec" SUF_8)
98 __ATOMIC_OPXX(atomic_dec_16,     uint16_t, "dec" SUF_16)
99 __ATOMIC_OPXX(atomic_dec_32,     uint32_t, "dec" SUF_32)
100 __ATOMIC_OP64(atomic_dec_64,     uint64_t, "dec" SUF_64)
101 __ATOMIC_OPXX(atomic_dec_uchar,  uchar_t,  "dec" SUF_8)
102 __ATOMIC_OPXX(atomic_dec_ushort, ushort_t, "dec" SUF_16)
103 __ATOMIC_OPXX(atomic_dec_uint,   uint_t,   "dec" SUF_32)
104 __ATOMIC_OPXX(atomic_dec_ulong,  ulong_t,  "dec" SUF_LONG)
105 
106 #undef __ATOMIC_OPXX
107 
108 #define	__ATOMIC_OPXX(fxn, type1, type2, op)				\
109 extern __GNU_INLINE void						\
110 fxn(volatile type1 *target, type2 delta)				\
111 {									\
112 	__asm__ __volatile__(						\
113 	    "lock; " op " %1,%0"					\
114 	    : "+m" (*target)						\
115 	    : "ir" (delta));						\
116 }
117 
118 __ATOMIC_OPXX(atomic_add_8,     uint8_t,  int8_t,      "add" SUF_8)
119 __ATOMIC_OPXX(atomic_add_16,    uint16_t, int16_t,     "add" SUF_16)
120 __ATOMIC_OPXX(atomic_add_32,    uint32_t, int32_t,     "add" SUF_32)
121 __ATOMIC_OP64(atomic_add_64,    uint64_t, int64_t,     "add" SUF_64)
122 __ATOMIC_OPXX(atomic_add_char,  uchar_t,  signed char, "add" SUF_8)
123 __ATOMIC_OPXX(atomic_add_short, ushort_t, short,       "add" SUF_16)
124 __ATOMIC_OPXX(atomic_add_int,   uint_t,   int,         "add" SUF_32)
125 __ATOMIC_OPXX(atomic_add_long,  ulong_t,  long,        "add" SUF_LONG)
126 
127 /*
128  * We don't use the above macro here because atomic_add_ptr has an
129  * inconsistent type.  The first argument should really be a 'volatile void
130  * **'.
131  */
132 extern __GNU_INLINE void
133 atomic_add_ptr(volatile void *target, ssize_t delta)
134 {
135 	volatile void **tmp = (volatile void **)target;
136 
137 	__asm__ __volatile__(
138 	    "lock; add" SUF_PTR " %1,%0"
139 	    : "+m" (*tmp)
140 	    : "ir" (delta));
141 }
142 
143 __ATOMIC_OPXX(atomic_or_8,       uint8_t,  uint8_t,  "or" SUF_8)
144 __ATOMIC_OPXX(atomic_or_16,      uint16_t, uint16_t, "or" SUF_16)
145 __ATOMIC_OPXX(atomic_or_32,      uint32_t, uint32_t, "or" SUF_32)
146 __ATOMIC_OP64(atomic_or_64,      uint64_t, uint64_t, "or" SUF_64)
147 __ATOMIC_OPXX(atomic_or_uchar,   uchar_t,  uchar_t,  "or" SUF_8)
148 __ATOMIC_OPXX(atomic_or_ushort,  ushort_t, ushort_t, "or" SUF_16)
149 __ATOMIC_OPXX(atomic_or_uint,    uint_t,   uint_t,   "or" SUF_32)
150 __ATOMIC_OPXX(atomic_or_ulong,   ulong_t,  ulong_t,  "or" SUF_LONG)
151 
152 __ATOMIC_OPXX(atomic_and_8,      uint8_t,  uint8_t,  "and" SUF_8)
153 __ATOMIC_OPXX(atomic_and_16,     uint16_t, uint16_t, "and" SUF_16)
154 __ATOMIC_OPXX(atomic_and_32,     uint32_t, uint32_t, "and" SUF_32)
155 __ATOMIC_OP64(atomic_and_64,     uint64_t, uint64_t, "and" SUF_64)
156 __ATOMIC_OPXX(atomic_and_uchar,  uchar_t,  uchar_t,  "and" SUF_8)
157 __ATOMIC_OPXX(atomic_and_ushort, ushort_t, ushort_t, "and" SUF_16)
158 __ATOMIC_OPXX(atomic_and_uint,   uint_t,   uint_t,   "and" SUF_32)
159 __ATOMIC_OPXX(atomic_and_ulong,  ulong_t,  ulong_t,  "and" SUF_LONG)
160 
161 #undef __ATOMIC_OPXX
162 
163 #define	__ATOMIC_OPXX(fxn, type, op, reg)				\
164 extern __GNU_INLINE type						\
165 fxn(volatile type *target, type cmp, type new)				\
166 {									\
167 	type ret;							\
168 	__asm__ __volatile__(						\
169 	    "lock; " op " %2,%0"					\
170 	    : "+m" (*target), "=a" (ret)				\
171 	    : reg (new), "1" (cmp)					\
172 	    : "cc");							\
173 	return (ret);							\
174 }
175 
176 __ATOMIC_OPXX(atomic_cas_8,      uint8_t,  "cmpxchg" SUF_8,    "q")
177 __ATOMIC_OPXX(atomic_cas_16,     uint16_t, "cmpxchg" SUF_16,   "r")
178 __ATOMIC_OPXX(atomic_cas_32,     uint32_t, "cmpxchg" SUF_32,   "r")
179 __ATOMIC_OP64(atomic_cas_64,     uint64_t, "cmpxchg" SUF_64,   "r")
180 __ATOMIC_OPXX(atomic_cas_uchar,  uchar_t,  "cmpxchg" SUF_8,    "q")
181 __ATOMIC_OPXX(atomic_cas_ushort, ushort_t, "cmpxchg" SUF_16,   "r")
182 __ATOMIC_OPXX(atomic_cas_uint,   uint_t,   "cmpxchg" SUF_32,   "r")
183 __ATOMIC_OPXX(atomic_cas_ulong,  ulong_t,  "cmpxchg" SUF_LONG, "r")
184 
185 #undef __ATOMIC_OPXX
186 
187 /*
188  * We don't use the above macro here because atomic_cas_ptr has an
189  * inconsistent type.  The first argument should really be a 'volatile void
190  * **'.
191  */
192 extern __GNU_INLINE void *
193 atomic_cas_ptr(volatile void *target, void *cmp, void *new)
194 {
195 	volatile void **tmp = (volatile void **)target;
196 	void *ret;
197 
198 	__asm__ __volatile__(
199 	    "lock; cmpxchg" SUF_PTR " %2,%0"
200 	    : "+m" (*tmp), "=a" (ret)
201 	    : "r" (new), "1" (cmp)
202 	    : "cc");
203 
204 	return (ret);
205 }
206 
207 #define	__ATOMIC_OPXX(fxn, type, op, reg)				\
208 extern __GNU_INLINE type						\
209 fxn(volatile type *target, type val)					\
210 {									\
211 	__asm__ __volatile__(						\
212 	    op " %1,%0"							\
213 	    : "+m" (*target), "+" reg (val));				\
214 	return (val);							\
215 }
216 
217 __ATOMIC_OPXX(atomic_swap_8,      uint8_t,  "xchg" SUF_8,    "q")
218 __ATOMIC_OPXX(atomic_swap_16,     uint16_t, "xchg" SUF_16,   "r")
219 __ATOMIC_OPXX(atomic_swap_32,     uint32_t, "xchg" SUF_32,   "r")
220 __ATOMIC_OP64(atomic_swap_64,     uint64_t, "xchg" SUF_64,   "r")
221 __ATOMIC_OPXX(atomic_swap_uchar,  uchar_t,  "xchg" SUF_8,    "q")
222 __ATOMIC_OPXX(atomic_swap_ushort, ushort_t, "xchg" SUF_16,   "r")
223 __ATOMIC_OPXX(atomic_swap_uint,   uint_t,   "xchg" SUF_32,   "r")
224 __ATOMIC_OPXX(atomic_swap_ulong,  ulong_t,  "xchg" SUF_LONG, "r")
225 
226 #undef __ATOMIC_OPXX
227 
228 /*
229  * We don't use the above macro here because atomic_swap_ptr has an
230  * inconsistent type.  The first argument should really be a 'volatile void
231  * **'.
232  */
233 extern __GNU_INLINE void *
234 atomic_swap_ptr(volatile void *target, void *val)
235 {
236 	volatile void **tmp = (volatile void **)target;
237 
238 	__asm__ __volatile__(
239 	    "xchg" SUF_PTR " %1,%0"
240 	    : "+m" (*tmp), "+r" (val));
241 
242 	return (val);
243 }
244 
245 #else
246 #error	"port me"
247 #endif
248 
249 #undef SUF_8
250 #undef SUF_16
251 #undef SUF_32
252 #undef SUF_64
253 #undef SUF_LONG
254 #undef SUF_PTR
255 
256 #undef __ATOMIC_OP64
257 
258 /* END CSTYLED */
259 
260 #endif /* !__lint && __GNUC__ */
261 
262 #ifdef __cplusplus
263 }
264 #endif
265 
266 #endif	/* _ASM_ATOMIC_H */
267