xref: /freebsd/sys/i386/include/atomic.h (revision 640235e2c2ba32947f7c59d168437ffa1280f1e6)
1 /*-
2  * Copyright (c) 1998 Doug Rabson
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 #ifndef _MACHINE_ATOMIC_H_
29 #define	_MACHINE_ATOMIC_H_
30 
31 #ifndef _SYS_CDEFS_H_
32 #error this file needs sys/cdefs.h as a prerequisite
33 #endif
34 
35 #ifdef _KERNEL
36 #include <machine/md_var.h>
37 #include <machine/specialreg.h>
38 #endif
39 
40 #ifndef __OFFSETOF_MONITORBUF
41 /*
42  * __OFFSETOF_MONITORBUF == __pcpu_offset(pc_monitorbuf).
43  *
44  * The open-coded number is used instead of the symbolic expression to
45  * avoid a dependency on sys/pcpu.h in machine/atomic.h consumers.
46  * An assertion in i386/vm_machdep.c ensures that the value is correct.
47  */
48 #define	__OFFSETOF_MONITORBUF	0x180
49 
50 static __inline void
51 __mbk(void)
52 {
53 
54 	__asm __volatile("lock; addl $0,%%fs:%0"
55 	    : "+m" (*(u_int *)__OFFSETOF_MONITORBUF) : : "memory", "cc");
56 }
57 
58 static __inline void
59 __mbu(void)
60 {
61 
62 	__asm __volatile("lock; addl $0,(%%esp)" : : : "memory", "cc");
63 }
64 #endif
65 
66 /*
67  * Various simple operations on memory, each of which is atomic in the
68  * presence of interrupts and multiple processors.
69  *
70  * atomic_set_char(P, V)	(*(u_char *)(P) |= (V))
71  * atomic_clear_char(P, V)	(*(u_char *)(P) &= ~(V))
72  * atomic_add_char(P, V)	(*(u_char *)(P) += (V))
73  * atomic_subtract_char(P, V)	(*(u_char *)(P) -= (V))
74  *
75  * atomic_set_short(P, V)	(*(u_short *)(P) |= (V))
76  * atomic_clear_short(P, V)	(*(u_short *)(P) &= ~(V))
77  * atomic_add_short(P, V)	(*(u_short *)(P) += (V))
78  * atomic_subtract_short(P, V)	(*(u_short *)(P) -= (V))
79  *
80  * atomic_set_int(P, V)		(*(u_int *)(P) |= (V))
81  * atomic_clear_int(P, V)	(*(u_int *)(P) &= ~(V))
82  * atomic_add_int(P, V)		(*(u_int *)(P) += (V))
83  * atomic_subtract_int(P, V)	(*(u_int *)(P) -= (V))
84  * atomic_swap_int(P, V)	(return (*(u_int *)(P)); *(u_int *)(P) = (V);)
85  * atomic_readandclear_int(P)	(return (*(u_int *)(P)); *(u_int *)(P) = 0;)
86  *
87  * atomic_set_long(P, V)	(*(u_long *)(P) |= (V))
88  * atomic_clear_long(P, V)	(*(u_long *)(P) &= ~(V))
89  * atomic_add_long(P, V)	(*(u_long *)(P) += (V))
90  * atomic_subtract_long(P, V)	(*(u_long *)(P) -= (V))
91  * atomic_swap_long(P, V)	(return (*(u_long *)(P)); *(u_long *)(P) = (V);)
92  * atomic_readandclear_long(P)	(return (*(u_long *)(P)); *(u_long *)(P) = 0;)
93  */
94 
95 /*
96  * The above functions are expanded inline in the statically-linked
97  * kernel.  Lock prefixes are generated if an SMP kernel is being
98  * built.
99  *
100  * Kernel modules call real functions which are built into the kernel.
101  * This allows kernel modules to be portable between UP and SMP systems.
102  */
103 #if defined(KLD_MODULE) || !defined(__GNUCLIKE_ASM)
104 #define	ATOMIC_ASM(NAME, TYPE, OP, CONS, V)			\
105 void atomic_##NAME##_##TYPE(volatile u_##TYPE *p, u_##TYPE v);	\
106 void atomic_##NAME##_barr_##TYPE(volatile u_##TYPE *p, u_##TYPE v)
107 
108 int	atomic_cmpset_int(volatile u_int *dst, u_int expect, u_int src);
109 u_int	atomic_fetchadd_int(volatile u_int *p, u_int v);
110 int	atomic_testandset_int(volatile u_int *p, u_int v);
111 int	atomic_testandclear_int(volatile u_int *p, u_int v);
112 void	atomic_thread_fence_acq(void);
113 void	atomic_thread_fence_acq_rel(void);
114 void	atomic_thread_fence_rel(void);
115 void	atomic_thread_fence_seq_cst(void);
116 
117 #define	ATOMIC_LOAD(TYPE)					\
118 u_##TYPE	atomic_load_acq_##TYPE(volatile u_##TYPE *p)
119 #define	ATOMIC_STORE(TYPE)					\
120 void		atomic_store_rel_##TYPE(volatile u_##TYPE *p, u_##TYPE v)
121 
122 int		atomic_cmpset_64(volatile uint64_t *, uint64_t, uint64_t);
123 uint64_t	atomic_load_acq_64(volatile uint64_t *);
124 void		atomic_store_rel_64(volatile uint64_t *, uint64_t);
125 uint64_t	atomic_swap_64(volatile uint64_t *, uint64_t);
126 
127 #else /* !KLD_MODULE && __GNUCLIKE_ASM */
128 
129 /*
130  * For userland, always use lock prefixes so that the binaries will run
131  * on both SMP and !SMP systems.
132  */
133 #if defined(SMP) || !defined(_KERNEL)
134 #define	MPLOCKED	"lock ; "
135 #else
136 #define	MPLOCKED
137 #endif
138 
139 /*
140  * The assembly is volatilized to avoid code chunk removal by the compiler.
141  * GCC aggressively reorders operations and memory clobbering is necessary
142  * in order to avoid that for memory barriers.
143  */
144 #define	ATOMIC_ASM(NAME, TYPE, OP, CONS, V)		\
145 static __inline void					\
146 atomic_##NAME##_##TYPE(volatile u_##TYPE *p, u_##TYPE v)\
147 {							\
148 	__asm __volatile(MPLOCKED OP			\
149 	: "+m" (*p)					\
150 	: CONS (V)					\
151 	: "cc");					\
152 }							\
153 							\
154 static __inline void					\
155 atomic_##NAME##_barr_##TYPE(volatile u_##TYPE *p, u_##TYPE v)\
156 {							\
157 	__asm __volatile(MPLOCKED OP			\
158 	: "+m" (*p)					\
159 	: CONS (V)					\
160 	: "memory", "cc");				\
161 }							\
162 struct __hack
163 
164 /*
165  * Atomic compare and set, used by the mutex functions
166  *
167  * if (*dst == expect) *dst = src (all 32 bit words)
168  *
169  * Returns 0 on failure, non-zero on success
170  */
171 
172 #ifdef CPU_DISABLE_CMPXCHG
173 
174 static __inline int
175 atomic_cmpset_int(volatile u_int *dst, u_int expect, u_int src)
176 {
177 	u_char res;
178 
179 	__asm __volatile(
180 	"	pushfl ;		"
181 	"	cli ;			"
182 	"	cmpl	%3,%1 ;		"
183 	"	jne	1f ;		"
184 	"	movl	%2,%1 ;		"
185 	"1:				"
186 	"       sete	%0 ;		"
187 	"	popfl ;			"
188 	"# atomic_cmpset_int"
189 	: "=q" (res),			/* 0 */
190 	  "+m" (*dst)			/* 1 */
191 	: "r" (src),			/* 2 */
192 	  "r" (expect)			/* 3 */
193 	: "memory");
194 	return (res);
195 }
196 
197 #else /* !CPU_DISABLE_CMPXCHG */
198 
199 static __inline int
200 atomic_cmpset_int(volatile u_int *dst, u_int expect, u_int src)
201 {
202 	u_char res;
203 
204 	__asm __volatile(
205 	"	" MPLOCKED "		"
206 	"	cmpxchgl %3,%1 ;	"
207 	"       sete	%0 ;		"
208 	"# atomic_cmpset_int"
209 	: "=q" (res),			/* 0 */
210 	  "+m" (*dst),			/* 1 */
211 	  "+a" (expect)			/* 2 */
212 	: "r" (src)			/* 3 */
213 	: "memory", "cc");
214 	return (res);
215 }
216 
217 #endif /* CPU_DISABLE_CMPXCHG */
218 
219 /*
220  * Atomically add the value of v to the integer pointed to by p and return
221  * the previous value of *p.
222  */
223 static __inline u_int
224 atomic_fetchadd_int(volatile u_int *p, u_int v)
225 {
226 
227 	__asm __volatile(
228 	"	" MPLOCKED "		"
229 	"	xaddl	%0,%1 ;		"
230 	"# atomic_fetchadd_int"
231 	: "+r" (v),			/* 0 */
232 	  "+m" (*p)			/* 1 */
233 	: : "cc");
234 	return (v);
235 }
236 
237 static __inline int
238 atomic_testandset_int(volatile u_int *p, u_int v)
239 {
240 	u_char res;
241 
242 	__asm __volatile(
243 	"	" MPLOCKED "		"
244 	"	btsl	%2,%1 ;		"
245 	"	setc	%0 ;		"
246 	"# atomic_testandset_int"
247 	: "=q" (res),			/* 0 */
248 	  "+m" (*p)			/* 1 */
249 	: "Ir" (v & 0x1f)		/* 2 */
250 	: "cc");
251 	return (res);
252 }
253 
254 static __inline int
255 atomic_testandclear_int(volatile u_int *p, u_int v)
256 {
257 	u_char res;
258 
259 	__asm __volatile(
260 	"	" MPLOCKED "		"
261 	"	btrl	%2,%1 ;		"
262 	"	setc	%0 ;		"
263 	"# atomic_testandclear_int"
264 	: "=q" (res),			/* 0 */
265 	  "+m" (*p)			/* 1 */
266 	: "Ir" (v & 0x1f)		/* 2 */
267 	: "cc");
268 	return (res);
269 }
270 
271 /*
272  * We assume that a = b will do atomic loads and stores.  Due to the
273  * IA32 memory model, a simple store guarantees release semantics.
274  *
275  * However, a load may pass a store if they are performed on distinct
276  * addresses, so we need Store/Load barrier for sequentially
277  * consistent fences in SMP kernels.  We use "lock addl $0,mem" for a
278  * Store/Load barrier, as recommended by the AMD Software Optimization
279  * Guide, and not mfence.  In the kernel, we use a private per-cpu
280  * cache line for "mem", to avoid introducing false data
281  * dependencies.  In user space, we use the word at the top of the
282  * stack.
283  *
284  * For UP kernels, however, the memory of the single processor is
285  * always consistent, so we only need to stop the compiler from
286  * reordering accesses in a way that violates the semantics of acquire
287  * and release.
288  */
289 
290 #if defined(_KERNEL)
291 #if defined(SMP)
292 #define	__storeload_barrier()	__mbk()
293 #else /* _KERNEL && UP */
294 #define	__storeload_barrier()	__compiler_membar()
295 #endif /* SMP */
296 #else /* !_KERNEL */
297 #define	__storeload_barrier()	__mbu()
298 #endif /* _KERNEL*/
299 
300 #define	ATOMIC_LOAD(TYPE)					\
301 static __inline u_##TYPE					\
302 atomic_load_acq_##TYPE(volatile u_##TYPE *p)			\
303 {								\
304 	u_##TYPE res;						\
305 								\
306 	res = *p;						\
307 	__compiler_membar();					\
308 	return (res);						\
309 }								\
310 struct __hack
311 
312 #define	ATOMIC_STORE(TYPE)					\
313 static __inline void						\
314 atomic_store_rel_##TYPE(volatile u_##TYPE *p, u_##TYPE v)	\
315 {								\
316 								\
317 	__compiler_membar();					\
318 	*p = v;							\
319 }								\
320 struct __hack
321 
322 static __inline void
323 atomic_thread_fence_acq(void)
324 {
325 
326 	__compiler_membar();
327 }
328 
329 static __inline void
330 atomic_thread_fence_rel(void)
331 {
332 
333 	__compiler_membar();
334 }
335 
336 static __inline void
337 atomic_thread_fence_acq_rel(void)
338 {
339 
340 	__compiler_membar();
341 }
342 
343 static __inline void
344 atomic_thread_fence_seq_cst(void)
345 {
346 
347 	__storeload_barrier();
348 }
349 
350 #ifdef _KERNEL
351 
352 #ifdef WANT_FUNCTIONS
353 int		atomic_cmpset_64_i386(volatile uint64_t *, uint64_t, uint64_t);
354 int		atomic_cmpset_64_i586(volatile uint64_t *, uint64_t, uint64_t);
355 uint64_t	atomic_load_acq_64_i386(volatile uint64_t *);
356 uint64_t	atomic_load_acq_64_i586(volatile uint64_t *);
357 void		atomic_store_rel_64_i386(volatile uint64_t *, uint64_t);
358 void		atomic_store_rel_64_i586(volatile uint64_t *, uint64_t);
359 uint64_t	atomic_swap_64_i386(volatile uint64_t *, uint64_t);
360 uint64_t	atomic_swap_64_i586(volatile uint64_t *, uint64_t);
361 #endif
362 
363 /* I486 does not support SMP or CMPXCHG8B. */
364 static __inline int
365 atomic_cmpset_64_i386(volatile uint64_t *dst, uint64_t expect, uint64_t src)
366 {
367 	volatile uint32_t *p;
368 	u_char res;
369 
370 	p = (volatile uint32_t *)dst;
371 	__asm __volatile(
372 	"	pushfl ;		"
373 	"	cli ;			"
374 	"	xorl	%1,%%eax ;	"
375 	"	xorl	%2,%%edx ;	"
376 	"	orl	%%edx,%%eax ;	"
377 	"	jne	1f ;		"
378 	"	movl	%4,%1 ;		"
379 	"	movl	%5,%2 ;		"
380 	"1:				"
381 	"	sete	%3 ;		"
382 	"	popfl"
383 	: "+A" (expect),		/* 0 */
384 	  "+m" (*p),			/* 1 */
385 	  "+m" (*(p + 1)),		/* 2 */
386 	  "=q" (res)			/* 3 */
387 	: "r" ((uint32_t)src),		/* 4 */
388 	  "r" ((uint32_t)(src >> 32))	/* 5 */
389 	: "memory", "cc");
390 	return (res);
391 }
392 
393 static __inline uint64_t
394 atomic_load_acq_64_i386(volatile uint64_t *p)
395 {
396 	volatile uint32_t *q;
397 	uint64_t res;
398 
399 	q = (volatile uint32_t *)p;
400 	__asm __volatile(
401 	"	pushfl ;		"
402 	"	cli ;			"
403 	"	movl	%1,%%eax ;	"
404 	"	movl	%2,%%edx ;	"
405 	"	popfl"
406 	: "=&A" (res)			/* 0 */
407 	: "m" (*q),			/* 1 */
408 	  "m" (*(q + 1))		/* 2 */
409 	: "memory");
410 	return (res);
411 }
412 
413 static __inline void
414 atomic_store_rel_64_i386(volatile uint64_t *p, uint64_t v)
415 {
416 	volatile uint32_t *q;
417 
418 	q = (volatile uint32_t *)p;
419 	__asm __volatile(
420 	"	pushfl ;		"
421 	"	cli ;			"
422 	"	movl	%%eax,%0 ;	"
423 	"	movl	%%edx,%1 ;	"
424 	"	popfl"
425 	: "=m" (*q),			/* 0 */
426 	  "=m" (*(q + 1))		/* 1 */
427 	: "A" (v)			/* 2 */
428 	: "memory");
429 }
430 
431 static __inline uint64_t
432 atomic_swap_64_i386(volatile uint64_t *p, uint64_t v)
433 {
434 	volatile uint32_t *q;
435 	uint64_t res;
436 
437 	q = (volatile uint32_t *)p;
438 	__asm __volatile(
439 	"	pushfl ;		"
440 	"	cli ;			"
441 	"	movl	%1,%%eax ;	"
442 	"	movl	%2,%%edx ;	"
443 	"	movl	%4,%2 ;		"
444 	"	movl	%3,%1 ;		"
445 	"	popfl"
446 	: "=&A" (res),			/* 0 */
447 	  "+m" (*q),			/* 1 */
448 	  "+m" (*(q + 1))		/* 2 */
449 	: "r" ((uint32_t)v),		/* 3 */
450 	  "r" ((uint32_t)(v >> 32)));	/* 4 */
451 	return (res);
452 }
453 
454 static __inline int
455 atomic_cmpset_64_i586(volatile uint64_t *dst, uint64_t expect, uint64_t src)
456 {
457 	u_char res;
458 
459 	__asm __volatile(
460 	"	" MPLOCKED "		"
461 	"	cmpxchg8b %1 ;		"
462 	"	sete	%0"
463 	: "=q" (res),			/* 0 */
464 	  "+m" (*dst),			/* 1 */
465 	  "+A" (expect)			/* 2 */
466 	: "b" ((uint32_t)src),		/* 3 */
467 	  "c" ((uint32_t)(src >> 32))	/* 4 */
468 	: "memory", "cc");
469 	return (res);
470 }
471 
472 static __inline uint64_t
473 atomic_load_acq_64_i586(volatile uint64_t *p)
474 {
475 	uint64_t res;
476 
477 	__asm __volatile(
478 	"	movl	%%ebx,%%eax ;	"
479 	"	movl	%%ecx,%%edx ;	"
480 	"	" MPLOCKED "		"
481 	"	cmpxchg8b %1"
482 	: "=&A" (res),			/* 0 */
483 	  "+m" (*p)			/* 1 */
484 	: : "memory", "cc");
485 	return (res);
486 }
487 
488 static __inline void
489 atomic_store_rel_64_i586(volatile uint64_t *p, uint64_t v)
490 {
491 
492 	__asm __volatile(
493 	"	movl	%%eax,%%ebx ;	"
494 	"	movl	%%edx,%%ecx ;	"
495 	"1:				"
496 	"	" MPLOCKED "		"
497 	"	cmpxchg8b %0 ;		"
498 	"	jne	1b"
499 	: "+m" (*p),			/* 0 */
500 	  "+A" (v)			/* 1 */
501 	: : "ebx", "ecx", "memory", "cc");
502 }
503 
504 static __inline uint64_t
505 atomic_swap_64_i586(volatile uint64_t *p, uint64_t v)
506 {
507 
508 	__asm __volatile(
509 	"	movl	%%eax,%%ebx ;	"
510 	"	movl	%%edx,%%ecx ;	"
511 	"1:				"
512 	"	" MPLOCKED "		"
513 	"	cmpxchg8b %0 ;		"
514 	"	jne	1b"
515 	: "+m" (*p),			/* 0 */
516 	  "+A" (v)			/* 1 */
517 	: : "ebx", "ecx", "memory", "cc");
518 	return (v);
519 }
520 
521 static __inline int
522 atomic_cmpset_64(volatile uint64_t *dst, uint64_t expect, uint64_t src)
523 {
524 
525 	if ((cpu_feature & CPUID_CX8) == 0)
526 		return (atomic_cmpset_64_i386(dst, expect, src));
527 	else
528 		return (atomic_cmpset_64_i586(dst, expect, src));
529 }
530 
531 static __inline uint64_t
532 atomic_load_acq_64(volatile uint64_t *p)
533 {
534 
535 	if ((cpu_feature & CPUID_CX8) == 0)
536 		return (atomic_load_acq_64_i386(p));
537 	else
538 		return (atomic_load_acq_64_i586(p));
539 }
540 
541 static __inline void
542 atomic_store_rel_64(volatile uint64_t *p, uint64_t v)
543 {
544 
545 	if ((cpu_feature & CPUID_CX8) == 0)
546 		atomic_store_rel_64_i386(p, v);
547 	else
548 		atomic_store_rel_64_i586(p, v);
549 }
550 
551 static __inline uint64_t
552 atomic_swap_64(volatile uint64_t *p, uint64_t v)
553 {
554 
555 	if ((cpu_feature & CPUID_CX8) == 0)
556 		return (atomic_swap_64_i386(p, v));
557 	else
558 		return (atomic_swap_64_i586(p, v));
559 }
560 
561 #endif /* _KERNEL */
562 
563 #endif /* KLD_MODULE || !__GNUCLIKE_ASM */
564 
565 ATOMIC_ASM(set,	     char,  "orb %b1,%0",  "iq",  v);
566 ATOMIC_ASM(clear,    char,  "andb %b1,%0", "iq", ~v);
567 ATOMIC_ASM(add,	     char,  "addb %b1,%0", "iq",  v);
568 ATOMIC_ASM(subtract, char,  "subb %b1,%0", "iq",  v);
569 
570 ATOMIC_ASM(set,	     short, "orw %w1,%0",  "ir",  v);
571 ATOMIC_ASM(clear,    short, "andw %w1,%0", "ir", ~v);
572 ATOMIC_ASM(add,	     short, "addw %w1,%0", "ir",  v);
573 ATOMIC_ASM(subtract, short, "subw %w1,%0", "ir",  v);
574 
575 ATOMIC_ASM(set,	     int,   "orl %1,%0",   "ir",  v);
576 ATOMIC_ASM(clear,    int,   "andl %1,%0",  "ir", ~v);
577 ATOMIC_ASM(add,	     int,   "addl %1,%0",  "ir",  v);
578 ATOMIC_ASM(subtract, int,   "subl %1,%0",  "ir",  v);
579 
580 ATOMIC_ASM(set,	     long,  "orl %1,%0",   "ir",  v);
581 ATOMIC_ASM(clear,    long,  "andl %1,%0",  "ir", ~v);
582 ATOMIC_ASM(add,	     long,  "addl %1,%0",  "ir",  v);
583 ATOMIC_ASM(subtract, long,  "subl %1,%0",  "ir",  v);
584 
585 #define	ATOMIC_LOADSTORE(TYPE)				\
586 	ATOMIC_LOAD(TYPE);				\
587 	ATOMIC_STORE(TYPE)
588 
589 ATOMIC_LOADSTORE(char);
590 ATOMIC_LOADSTORE(short);
591 ATOMIC_LOADSTORE(int);
592 ATOMIC_LOADSTORE(long);
593 
594 #undef ATOMIC_ASM
595 #undef ATOMIC_LOAD
596 #undef ATOMIC_STORE
597 #undef ATOMIC_LOADSTORE
598 
599 #ifndef WANT_FUNCTIONS
600 
601 static __inline int
602 atomic_cmpset_long(volatile u_long *dst, u_long expect, u_long src)
603 {
604 
605 	return (atomic_cmpset_int((volatile u_int *)dst, (u_int)expect,
606 	    (u_int)src));
607 }
608 
609 static __inline u_long
610 atomic_fetchadd_long(volatile u_long *p, u_long v)
611 {
612 
613 	return (atomic_fetchadd_int((volatile u_int *)p, (u_int)v));
614 }
615 
616 static __inline int
617 atomic_testandset_long(volatile u_long *p, u_int v)
618 {
619 
620 	return (atomic_testandset_int((volatile u_int *)p, v));
621 }
622 
623 static __inline int
624 atomic_testandclear_long(volatile u_long *p, u_int v)
625 {
626 
627 	return (atomic_testandclear_int((volatile u_int *)p, v));
628 }
629 
630 /* Read the current value and store a new value in the destination. */
631 #ifdef __GNUCLIKE_ASM
632 
633 static __inline u_int
634 atomic_swap_int(volatile u_int *p, u_int v)
635 {
636 
637 	__asm __volatile(
638 	"	xchgl	%1,%0 ;		"
639 	"# atomic_swap_int"
640 	: "+r" (v),			/* 0 */
641 	  "+m" (*p));			/* 1 */
642 	return (v);
643 }
644 
645 static __inline u_long
646 atomic_swap_long(volatile u_long *p, u_long v)
647 {
648 
649 	return (atomic_swap_int((volatile u_int *)p, (u_int)v));
650 }
651 
652 #else /* !__GNUCLIKE_ASM */
653 
654 u_int	atomic_swap_int(volatile u_int *p, u_int v);
655 u_long	atomic_swap_long(volatile u_long *p, u_long v);
656 
657 #endif /* __GNUCLIKE_ASM */
658 
659 #define	atomic_set_acq_char		atomic_set_barr_char
660 #define	atomic_set_rel_char		atomic_set_barr_char
661 #define	atomic_clear_acq_char		atomic_clear_barr_char
662 #define	atomic_clear_rel_char		atomic_clear_barr_char
663 #define	atomic_add_acq_char		atomic_add_barr_char
664 #define	atomic_add_rel_char		atomic_add_barr_char
665 #define	atomic_subtract_acq_char	atomic_subtract_barr_char
666 #define	atomic_subtract_rel_char	atomic_subtract_barr_char
667 
668 #define	atomic_set_acq_short		atomic_set_barr_short
669 #define	atomic_set_rel_short		atomic_set_barr_short
670 #define	atomic_clear_acq_short		atomic_clear_barr_short
671 #define	atomic_clear_rel_short		atomic_clear_barr_short
672 #define	atomic_add_acq_short		atomic_add_barr_short
673 #define	atomic_add_rel_short		atomic_add_barr_short
674 #define	atomic_subtract_acq_short	atomic_subtract_barr_short
675 #define	atomic_subtract_rel_short	atomic_subtract_barr_short
676 
677 #define	atomic_set_acq_int		atomic_set_barr_int
678 #define	atomic_set_rel_int		atomic_set_barr_int
679 #define	atomic_clear_acq_int		atomic_clear_barr_int
680 #define	atomic_clear_rel_int		atomic_clear_barr_int
681 #define	atomic_add_acq_int		atomic_add_barr_int
682 #define	atomic_add_rel_int		atomic_add_barr_int
683 #define	atomic_subtract_acq_int		atomic_subtract_barr_int
684 #define	atomic_subtract_rel_int		atomic_subtract_barr_int
685 #define	atomic_cmpset_acq_int		atomic_cmpset_int
686 #define	atomic_cmpset_rel_int		atomic_cmpset_int
687 
688 #define	atomic_set_acq_long		atomic_set_barr_long
689 #define	atomic_set_rel_long		atomic_set_barr_long
690 #define	atomic_clear_acq_long		atomic_clear_barr_long
691 #define	atomic_clear_rel_long		atomic_clear_barr_long
692 #define	atomic_add_acq_long		atomic_add_barr_long
693 #define	atomic_add_rel_long		atomic_add_barr_long
694 #define	atomic_subtract_acq_long	atomic_subtract_barr_long
695 #define	atomic_subtract_rel_long	atomic_subtract_barr_long
696 #define	atomic_cmpset_acq_long		atomic_cmpset_long
697 #define	atomic_cmpset_rel_long		atomic_cmpset_long
698 
699 #define	atomic_readandclear_int(p)	atomic_swap_int(p, 0)
700 #define	atomic_readandclear_long(p)	atomic_swap_long(p, 0)
701 
702 /* Operations on 8-bit bytes. */
703 #define	atomic_set_8		atomic_set_char
704 #define	atomic_set_acq_8	atomic_set_acq_char
705 #define	atomic_set_rel_8	atomic_set_rel_char
706 #define	atomic_clear_8		atomic_clear_char
707 #define	atomic_clear_acq_8	atomic_clear_acq_char
708 #define	atomic_clear_rel_8	atomic_clear_rel_char
709 #define	atomic_add_8		atomic_add_char
710 #define	atomic_add_acq_8	atomic_add_acq_char
711 #define	atomic_add_rel_8	atomic_add_rel_char
712 #define	atomic_subtract_8	atomic_subtract_char
713 #define	atomic_subtract_acq_8	atomic_subtract_acq_char
714 #define	atomic_subtract_rel_8	atomic_subtract_rel_char
715 #define	atomic_load_acq_8	atomic_load_acq_char
716 #define	atomic_store_rel_8	atomic_store_rel_char
717 
718 /* Operations on 16-bit words. */
719 #define	atomic_set_16		atomic_set_short
720 #define	atomic_set_acq_16	atomic_set_acq_short
721 #define	atomic_set_rel_16	atomic_set_rel_short
722 #define	atomic_clear_16		atomic_clear_short
723 #define	atomic_clear_acq_16	atomic_clear_acq_short
724 #define	atomic_clear_rel_16	atomic_clear_rel_short
725 #define	atomic_add_16		atomic_add_short
726 #define	atomic_add_acq_16	atomic_add_acq_short
727 #define	atomic_add_rel_16	atomic_add_rel_short
728 #define	atomic_subtract_16	atomic_subtract_short
729 #define	atomic_subtract_acq_16	atomic_subtract_acq_short
730 #define	atomic_subtract_rel_16	atomic_subtract_rel_short
731 #define	atomic_load_acq_16	atomic_load_acq_short
732 #define	atomic_store_rel_16	atomic_store_rel_short
733 
734 /* Operations on 32-bit double words. */
735 #define	atomic_set_32		atomic_set_int
736 #define	atomic_set_acq_32	atomic_set_acq_int
737 #define	atomic_set_rel_32	atomic_set_rel_int
738 #define	atomic_clear_32		atomic_clear_int
739 #define	atomic_clear_acq_32	atomic_clear_acq_int
740 #define	atomic_clear_rel_32	atomic_clear_rel_int
741 #define	atomic_add_32		atomic_add_int
742 #define	atomic_add_acq_32	atomic_add_acq_int
743 #define	atomic_add_rel_32	atomic_add_rel_int
744 #define	atomic_subtract_32	atomic_subtract_int
745 #define	atomic_subtract_acq_32	atomic_subtract_acq_int
746 #define	atomic_subtract_rel_32	atomic_subtract_rel_int
747 #define	atomic_load_acq_32	atomic_load_acq_int
748 #define	atomic_store_rel_32	atomic_store_rel_int
749 #define	atomic_cmpset_32	atomic_cmpset_int
750 #define	atomic_cmpset_acq_32	atomic_cmpset_acq_int
751 #define	atomic_cmpset_rel_32	atomic_cmpset_rel_int
752 #define	atomic_swap_32		atomic_swap_int
753 #define	atomic_readandclear_32	atomic_readandclear_int
754 #define	atomic_fetchadd_32	atomic_fetchadd_int
755 #define	atomic_testandset_32	atomic_testandset_int
756 #define	atomic_testandclear_32	atomic_testandclear_int
757 
758 /* Operations on pointers. */
759 #define	atomic_set_ptr(p, v) \
760 	atomic_set_int((volatile u_int *)(p), (u_int)(v))
761 #define	atomic_set_acq_ptr(p, v) \
762 	atomic_set_acq_int((volatile u_int *)(p), (u_int)(v))
763 #define	atomic_set_rel_ptr(p, v) \
764 	atomic_set_rel_int((volatile u_int *)(p), (u_int)(v))
765 #define	atomic_clear_ptr(p, v) \
766 	atomic_clear_int((volatile u_int *)(p), (u_int)(v))
767 #define	atomic_clear_acq_ptr(p, v) \
768 	atomic_clear_acq_int((volatile u_int *)(p), (u_int)(v))
769 #define	atomic_clear_rel_ptr(p, v) \
770 	atomic_clear_rel_int((volatile u_int *)(p), (u_int)(v))
771 #define	atomic_add_ptr(p, v) \
772 	atomic_add_int((volatile u_int *)(p), (u_int)(v))
773 #define	atomic_add_acq_ptr(p, v) \
774 	atomic_add_acq_int((volatile u_int *)(p), (u_int)(v))
775 #define	atomic_add_rel_ptr(p, v) \
776 	atomic_add_rel_int((volatile u_int *)(p), (u_int)(v))
777 #define	atomic_subtract_ptr(p, v) \
778 	atomic_subtract_int((volatile u_int *)(p), (u_int)(v))
779 #define	atomic_subtract_acq_ptr(p, v) \
780 	atomic_subtract_acq_int((volatile u_int *)(p), (u_int)(v))
781 #define	atomic_subtract_rel_ptr(p, v) \
782 	atomic_subtract_rel_int((volatile u_int *)(p), (u_int)(v))
783 #define	atomic_load_acq_ptr(p) \
784 	atomic_load_acq_int((volatile u_int *)(p))
785 #define	atomic_store_rel_ptr(p, v) \
786 	atomic_store_rel_int((volatile u_int *)(p), (v))
787 #define	atomic_cmpset_ptr(dst, old, new) \
788 	atomic_cmpset_int((volatile u_int *)(dst), (u_int)(old), (u_int)(new))
789 #define	atomic_cmpset_acq_ptr(dst, old, new) \
790 	atomic_cmpset_acq_int((volatile u_int *)(dst), (u_int)(old), \
791 	    (u_int)(new))
792 #define	atomic_cmpset_rel_ptr(dst, old, new) \
793 	atomic_cmpset_rel_int((volatile u_int *)(dst), (u_int)(old), \
794 	    (u_int)(new))
795 #define	atomic_swap_ptr(p, v) \
796 	atomic_swap_int((volatile u_int *)(p), (u_int)(v))
797 #define	atomic_readandclear_ptr(p) \
798 	atomic_readandclear_int((volatile u_int *)(p))
799 
800 #endif /* !WANT_FUNCTIONS */
801 
802 #if defined(_KERNEL)
803 #define	mb()	__mbk()
804 #define	wmb()	__mbk()
805 #define	rmb()	__mbk()
806 #else
807 #define	mb()	__mbu()
808 #define	wmb()	__mbu()
809 #define	rmb()	__mbu()
810 #endif
811 
812 #endif /* !_MACHINE_ATOMIC_H_ */
813