xref: /illumos-gate/usr/src/uts/intel/asm/atomic.h (revision 6a9ca708361200b105f7a016216808e6058d17cb)
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  * Copyright 2015 Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
27  */
28 
29 #ifndef _ASM_ATOMIC_H
30 #define	_ASM_ATOMIC_H
31 
32 #include <sys/ccompile.h>
33 #include <sys/types.h>
34 
35 #ifdef	__cplusplus
36 extern "C" {
37 #endif
38 
39 #if !defined(__lint) && defined(__GNUC__)
40 
41 /* BEGIN CSTYLED */
42 /*
43  * This file contains a number of static inline functions implementing
44  * various atomic variable functions.  Note that these are *not* all of the
45  * atomic_* functions as defined in usr/src/uts/common/sys/atomic.h.  All
46  * possible atomic_* functions are implemented in usr/src/common/atomic in
47  * pure assembly.  In the absence of an identically named function in this
48  * header file, any use of the function will result in the compiler emitting
49  * a function call as usual.  On the other hand, if an identically named
50  * function exists in this header as a static inline, the compiler will
51  * inline its contents and the linker never sees the symbol reference.  We
52  * use this to avoid implementing some of the more complex and less used
53  * functions and instead falling back to function calls.  Note that in some
54  * cases (e.g., atomic_inc_64) we implement a static inline only on AMD64
55  * but not i386.
56  */
57 
58 /*
59  * Instruction suffixes for various operand sizes (assuming AMD64)
60  */
61 #define	SUF_8		"b"
62 #define	SUF_16		"w"
63 #define	SUF_32		"l"
64 #define	SUF_64		"q"
65 
66 #if defined(__amd64)
67 #define	SUF_LONG	SUF_64
68 #define	SUF_PTR		SUF_64
69 #define	__ATOMIC_OP64(...)	__ATOMIC_OPXX(__VA_ARGS__)
70 #elif defined(__i386)
71 #define	SUF_LONG	SUF_32
72 #define	SUF_PTR		SUF_32
73 #define	__ATOMIC_OP64(...)
74 #else
75 #error "port me"
76 #endif
77 
78 #if defined(__amd64) || defined(__i386)
79 
80 #define	__ATOMIC_OPXX(fxn, type, op)					\
81 extern __GNU_INLINE void						\
82 fxn(volatile type *target)						\
83 {									\
84 	__asm__ __volatile__(						\
85 	    "lock; " op " %0"						\
86 	    : "+m" (*target)						\
87 	    : /* no inputs */						\
88 	    : "cc");							\
89 }
90 
91 __ATOMIC_OPXX(atomic_inc_8,      uint8_t,  "inc" SUF_8)
92 __ATOMIC_OPXX(atomic_inc_16,     uint16_t, "inc" SUF_16)
93 __ATOMIC_OPXX(atomic_inc_32,     uint32_t, "inc" SUF_32)
94 __ATOMIC_OP64(atomic_inc_64,     uint64_t, "inc" SUF_64)
95 __ATOMIC_OPXX(atomic_inc_uchar,  uchar_t,  "inc" SUF_8)
96 __ATOMIC_OPXX(atomic_inc_ushort, ushort_t, "inc" SUF_16)
97 __ATOMIC_OPXX(atomic_inc_uint,   uint_t,   "inc" SUF_32)
98 __ATOMIC_OPXX(atomic_inc_ulong,  ulong_t,  "inc" SUF_LONG)
99 
100 __ATOMIC_OPXX(atomic_dec_8,      uint8_t,  "dec" SUF_8)
101 __ATOMIC_OPXX(atomic_dec_16,     uint16_t, "dec" SUF_16)
102 __ATOMIC_OPXX(atomic_dec_32,     uint32_t, "dec" SUF_32)
103 __ATOMIC_OP64(atomic_dec_64,     uint64_t, "dec" SUF_64)
104 __ATOMIC_OPXX(atomic_dec_uchar,  uchar_t,  "dec" SUF_8)
105 __ATOMIC_OPXX(atomic_dec_ushort, ushort_t, "dec" SUF_16)
106 __ATOMIC_OPXX(atomic_dec_uint,   uint_t,   "dec" SUF_32)
107 __ATOMIC_OPXX(atomic_dec_ulong,  ulong_t,  "dec" SUF_LONG)
108 
109 #undef __ATOMIC_OPXX
110 
111 #define	__ATOMIC_OPXX(fxn, type1, type2, op, reg)			\
112 extern __GNU_INLINE void						\
113 fxn(volatile type1 *target, type2 delta)				\
114 {									\
115 	__asm__ __volatile__(						\
116 	    "lock; " op " %1,%0"					\
117 	    : "+m" (*target)						\
118 	    : "i" reg (delta)						\
119 	    : "cc");							\
120 }
121 
122 __ATOMIC_OPXX(atomic_add_8,     uint8_t,  int8_t,      "add" SUF_8,    "q")
123 __ATOMIC_OPXX(atomic_add_16,    uint16_t, int16_t,     "add" SUF_16,   "r")
124 __ATOMIC_OPXX(atomic_add_32,    uint32_t, int32_t,     "add" SUF_32,   "r")
125 __ATOMIC_OP64(atomic_add_64,    uint64_t, int64_t,     "add" SUF_64,   "r")
126 __ATOMIC_OPXX(atomic_add_char,  uchar_t,  signed char, "add" SUF_8,    "q")
127 __ATOMIC_OPXX(atomic_add_short, ushort_t, short,       "add" SUF_16,   "r")
128 __ATOMIC_OPXX(atomic_add_int,   uint_t,   int,         "add" SUF_32,   "r")
129 __ATOMIC_OPXX(atomic_add_long,  ulong_t,  long,        "add" SUF_LONG, "r")
130 
131 /*
132  * We don't use the above macro here because atomic_add_ptr has an
133  * inconsistent type.  The first argument should really be a 'volatile void
134  * **'.
135  */
136 extern __GNU_INLINE void
atomic_add_ptr(volatile void * target,ssize_t delta)137 atomic_add_ptr(volatile void *target, ssize_t delta)
138 {
139 	volatile void **tmp = (volatile void **)target;
140 
141 	__asm__ __volatile__(
142 	    "lock; add" SUF_PTR " %1,%0"
143 	    : "+m" (*tmp)
144 	    : "ir" (delta)
145 	    : "cc");
146 }
147 
148 __ATOMIC_OPXX(atomic_or_8,       uint8_t,  uint8_t,  "or" SUF_8,    "q")
149 __ATOMIC_OPXX(atomic_or_16,      uint16_t, uint16_t, "or" SUF_16,   "r")
150 __ATOMIC_OPXX(atomic_or_32,      uint32_t, uint32_t, "or" SUF_32,   "r")
151 __ATOMIC_OP64(atomic_or_64,      uint64_t, uint64_t, "or" SUF_64,   "r")
152 __ATOMIC_OPXX(atomic_or_uchar,   uchar_t,  uchar_t,  "or" SUF_8,    "q")
153 __ATOMIC_OPXX(atomic_or_ushort,  ushort_t, ushort_t, "or" SUF_16,   "r")
154 __ATOMIC_OPXX(atomic_or_uint,    uint_t,   uint_t,   "or" SUF_32,   "r")
155 __ATOMIC_OPXX(atomic_or_ulong,   ulong_t,  ulong_t,  "or" SUF_LONG, "r")
156 
157 __ATOMIC_OPXX(atomic_and_8,      uint8_t,  uint8_t,  "and" SUF_8,    "q")
158 __ATOMIC_OPXX(atomic_and_16,     uint16_t, uint16_t, "and" SUF_16,   "r")
159 __ATOMIC_OPXX(atomic_and_32,     uint32_t, uint32_t, "and" SUF_32,   "r")
160 __ATOMIC_OP64(atomic_and_64,     uint64_t, uint64_t, "and" SUF_64,   "r")
161 __ATOMIC_OPXX(atomic_and_uchar,  uchar_t,  uchar_t,  "and" SUF_8,    "q")
162 __ATOMIC_OPXX(atomic_and_ushort, ushort_t, ushort_t, "and" SUF_16,   "r")
163 __ATOMIC_OPXX(atomic_and_uint,   uint_t,   uint_t,   "and" SUF_32,   "r")
164 __ATOMIC_OPXX(atomic_and_ulong,  ulong_t,  ulong_t,  "and" SUF_LONG, "r")
165 
166 #undef __ATOMIC_OPXX
167 
168 #define	__ATOMIC_OPXX(fxn, type, op, reg)				\
169 extern __GNU_INLINE type						\
170 fxn(volatile type *target, type cmp, type new)				\
171 {									\
172 	type ret;							\
173 	__asm__ __volatile__(						\
174 	    "lock; " op " %2,%0"					\
175 	    : "+m" (*target), "=a" (ret)				\
176 	    : reg (new), "1" (cmp)					\
177 	    : "cc");							\
178 	return (ret);							\
179 }
180 
181 __ATOMIC_OPXX(atomic_cas_8,      uint8_t,  "cmpxchg" SUF_8,    "q")
182 __ATOMIC_OPXX(atomic_cas_16,     uint16_t, "cmpxchg" SUF_16,   "r")
183 __ATOMIC_OPXX(atomic_cas_32,     uint32_t, "cmpxchg" SUF_32,   "r")
184 __ATOMIC_OP64(atomic_cas_64,     uint64_t, "cmpxchg" SUF_64,   "r")
185 __ATOMIC_OPXX(atomic_cas_uchar,  uchar_t,  "cmpxchg" SUF_8,    "q")
186 __ATOMIC_OPXX(atomic_cas_ushort, ushort_t, "cmpxchg" SUF_16,   "r")
187 __ATOMIC_OPXX(atomic_cas_uint,   uint_t,   "cmpxchg" SUF_32,   "r")
188 __ATOMIC_OPXX(atomic_cas_ulong,  ulong_t,  "cmpxchg" SUF_LONG, "r")
189 
190 #undef __ATOMIC_OPXX
191 
192 /*
193  * We don't use the above macro here because atomic_cas_ptr has an
194  * inconsistent type.  The first argument should really be a 'volatile void
195  * **'.
196  */
197 extern __GNU_INLINE void *
atomic_cas_ptr(volatile void * target,void * cmp,void * new)198 atomic_cas_ptr(volatile void *target, void *cmp, void *new)
199 {
200 	volatile void **tmp = (volatile void **)target;
201 	void *ret;
202 
203 	__asm__ __volatile__(
204 	    "lock; cmpxchg" SUF_PTR " %2,%0"
205 	    : "+m" (*tmp), "=a" (ret)
206 	    : "r" (new), "1" (cmp)
207 	    : "cc");
208 
209 	return (ret);
210 }
211 
212 #define	__ATOMIC_OPXX(fxn, type, op, reg)				\
213 extern __GNU_INLINE type						\
214 fxn(volatile type *target, type val)					\
215 {									\
216 	__asm__ __volatile__(						\
217 	    op " %1,%0"							\
218 	    : "+m" (*target), "+" reg (val));				\
219 	return (val);							\
220 }
221 
222 __ATOMIC_OPXX(atomic_swap_8,      uint8_t,  "xchg" SUF_8,    "q")
223 __ATOMIC_OPXX(atomic_swap_16,     uint16_t, "xchg" SUF_16,   "r")
224 __ATOMIC_OPXX(atomic_swap_32,     uint32_t, "xchg" SUF_32,   "r")
225 __ATOMIC_OP64(atomic_swap_64,     uint64_t, "xchg" SUF_64,   "r")
226 __ATOMIC_OPXX(atomic_swap_uchar,  uchar_t,  "xchg" SUF_8,    "q")
227 __ATOMIC_OPXX(atomic_swap_ushort, ushort_t, "xchg" SUF_16,   "r")
228 __ATOMIC_OPXX(atomic_swap_uint,   uint_t,   "xchg" SUF_32,   "r")
229 __ATOMIC_OPXX(atomic_swap_ulong,  ulong_t,  "xchg" SUF_LONG, "r")
230 
231 #undef __ATOMIC_OPXX
232 
233 /*
234  * We don't use the above macro here because atomic_swap_ptr has an
235  * inconsistent type.  The first argument should really be a 'volatile void
236  * **'.
237  */
238 extern __GNU_INLINE void *
atomic_swap_ptr(volatile void * target,void * val)239 atomic_swap_ptr(volatile void *target, void *val)
240 {
241 	volatile void **tmp = (volatile void **)target;
242 
243 	__asm__ __volatile__(
244 	    "xchg" SUF_PTR " %1,%0"
245 	    : "+m" (*tmp), "+r" (val));
246 
247 	return (val);
248 }
249 
250 #else
251 #error	"port me"
252 #endif
253 
254 #undef SUF_8
255 #undef SUF_16
256 #undef SUF_32
257 #undef SUF_64
258 #undef SUF_LONG
259 #undef SUF_PTR
260 
261 #undef __ATOMIC_OP64
262 
263 /* END CSTYLED */
264 
265 #endif /* !__lint && __GNUC__ */
266 
267 #ifdef __cplusplus
268 }
269 #endif
270 
271 #endif	/* _ASM_ATOMIC_H */
272