summaryrefslogtreecommitdiffstats
path: root/arch/s390/include/asm/atomic.h
blob: 5c5ba10384c2ee824065f5ae2ee8ac92a7cf3ab6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
#ifndef __ARCH_S390_ATOMIC__
#define __ARCH_S390_ATOMIC__

/*
 * Copyright 1999,2009 IBM Corp.
 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>,
 *	      Denis Joseph Barrow,
 *	      Arnd Bergmann <arndb@de.ibm.com>,
 *
 * Atomic operations that C can't guarantee us.
 * Useful for resource counting etc.
 * s390 uses 'Compare And Swap' for atomicity in SMP enviroment.
 *
 */

#include <linux/compiler.h>
#include <linux/types.h>
#include <asm/system.h>

#define ATOMIC_INIT(i)  { (i) }

#define __CS_LOOP(ptr, op_val, op_string) ({				\
	int old_val, new_val;						\
	asm volatile(							\
		"	l	%0,%2\n"				\
		"0:	lr	%1,%0\n"				\
		op_string "	%1,%3\n"				\
		"	cs	%0,%1,%2\n"				\
		"	jl	0b"					\
		: "=&d" (old_val), "=&d" (new_val),			\
		  "=Q" (((atomic_t *)(ptr))->counter)			\
		: "d" (op_val),	 "Q" (((atomic_t *)(ptr))->counter)	\
		: "cc", "memory");					\
	new_val;							\
})

static inline int atomic_read(const atomic_t *v)
{
	int c;

	asm volatile(
		"	l	%0,%1\n"
		: "=d" (c) : "Q" (v->counter));
	return c;
}

static inline void atomic_set(atomic_t *v, int i)
{
	asm volatile(
		"	st	%1,%0\n"
		: "=Q" (v->counter) : "d" (i));
}

static inline int atomic_add_return(int i, atomic_t *v)
{
	return __CS_LOOP(v, i, "ar");
}
#define atomic_add(_i, _v)		atomic_add_return(_i, _v)
#define atomic_add_negative(_i, _v)	(atomic_add_return(_i, _v) < 0)
#define atomic_inc(_v)			atomic_add_return(1, _v)
#define atomic_inc_return(_v)		atomic_add_return(1, _v)
#define atomic_inc_and_test(_v)		(atomic_add_return(1, _v) == 0)

static inline int atomic_sub_return(int i, atomic_t *v)
{
	return __CS_LOOP(v, i, "sr");
}
#define atomic_sub(_i, _v)		atomic_sub_return(_i, _v)
#define atomic_sub_and_test(_i, _v)	(atomic_sub_return(_i, _v) == 0)
#define atomic_dec(_v)			atomic_sub_return(1, _v)
#define atomic_dec_return(_v)		atomic_sub_return(1, _v)
#define atomic_dec_and_test(_v)		(atomic_sub_return(1, _v) == 0)

static inline void atomic_clear_mask(unsigned long mask, atomic_t *v)
{
	__CS_LOOP(v, ~mask, "nr");
}

static inline void atomic_set_mask(unsigned long mask, atomic_t *v)
{
	__CS_LOOP(v, mask, "or");
}

#define atomic_xchg(v, new) (xchg(&((v)->counter), new))

static inline int atomic_cmpxchg(atomic_t *v, int old, int new)
{
	asm volatile(
		"	cs	%0,%2,%1"
		: "+d" (old), "=Q" (v->counter)
		: "d" (new), "Q" (v->counter)
		: "cc", "memory");
	return old;
}

static inline int atomic_add_unless(atomic_t *v, int a, int u)
{
	int c, old;
	c = atomic_read(v);
	for (;;) {
		if (unlikely(c == u))
			break;
		old = atomic_cmpxchg(v, c, c + a);
		if (likely(old == c))
			break;
		c = old;
	}
	return c != u;
}

#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0)

#undef __CS_LOOP

#define ATOMIC64_INIT(i)  { (i) }

#ifdef CONFIG_64BIT

#define __CSG_LOOP(ptr, op_val, op_string) ({				\
	long long old_val, new_val;					\
	asm volatile(							\
		"	lg	%0,%2\n"				\
		"0:	lgr	%1,%0\n"				\
		op_string "	%1,%3\n"				\
		"	csg	%0,%1,%2\n"				\
		"	jl	0b"					\
		: "=&d" (old_val), "=&d" (new_val),			\
		  "=Q" (((atomic_t *)(ptr))->counter)			\
		: "d" (op_val),	"Q" (((atomic_t *)(ptr))->counter)	\
		: "cc", "memory");					\
	new_val;							\
})

static inline long long atomic64_read(const atomic64_t *v)
{
	long long c;

	asm volatile(
		"	lg	%0,%1\n"
		: "=d" (c) : "Q" (v->counter));
	return c;
}

static inline void atomic64_set(atomic64_t *v, long long i)
{
	asm volatile(
		"	stg	%1,%0\n"
		: "=Q" (v->counter) : "d" (i));
}

static inline long long atomic64_add_return(long long i, atomic64_t *v)
{
	return __CSG_LOOP(v, i, "agr");
}

static inline long long atomic64_sub_return(long long i, atomic64_t *v)
{
	return __CSG_LOOP(v, i, "sgr");
}

static inline void atomic64_clear_mask(unsigned long mask, atomic64_t *v)
{
	__CSG_LOOP(v, ~mask, "ngr");
}

static inline void atomic64_set_mask(unsigned long mask, atomic64_t *v)
{
	__CSG_LOOP(v, mask, "ogr");
}

#define atomic64_xchg(v, new) (xchg(&((v)->counter), new))

static inline long long atomic64_cmpxchg(atomic64_t *v,
					     long long old, long long new)
{
	asm volatile(
		"	csg	%0,%2,%1"
		: "+d" (old), "=Q" (v->counter)
		: "d" (new), "Q" (v->counter)
		: "cc", "memory");
	return old;
}

#undef __CSG_LOOP

#else /* CONFIG_64BIT */

typedef struct {
	long long counter;
} atomic64_t;

static inline long long atomic64_read(const atomic64_t *v)
{
	register_pair rp;

	asm volatile(
		"	lm	%0,%N0,%1"
		: "=&d" (rp) : "Q" (v->counter)	);
	return rp.pair;
}

static inline void atomic64_set(atomic64_t *v, long long i)
{
	register_pair rp = {.pair = i};

	asm volatile(
		"	stm	%1,%N1,%0"
		: "=Q" (v->counter) : "d" (rp) );
}

static inline long long atomic64_xchg(atomic64_t *v, long long new)
{
	register_pair rp_new = {.pair = new};
	register_pair rp_old;

	asm volatile(
		"	lm	%0,%N0,%1\n"
		"0:	cds	%0,%2,%1\n"
		"	jl	0b\n"
		: "=&d" (rp_old), "=Q" (v->counter)
		: "d" (rp_new), "Q" (v->counter)
		: "cc");
	return rp_old.pair;
}

static inline long long atomic64_cmpxchg(atomic64_t *v,
					 long long old, long long new)
{
	register_pair rp_old = {.pair = old};
	register_pair rp_new = {.pair = new};

	asm volatile(
		"	cds	%0,%2,%1"
		: "+&d" (rp_old), "=Q" (v->counter)
		: "d" (rp_new), "Q" (v->counter)
		: "cc");
	return rp_old.pair;
}


static inline long long atomic64_add_return(long long i, atomic64_t *v)
{
	long long old, new;

	do {
		old = atomic64_read(v);
		new = old + i;
	} while (atomic64_cmpxchg(v, old, new) != old);
	return new;
}

static inline long long atomic64_sub_return(long long i, atomic64_t *v)
{
	long long old, new;

	do {
		old = atomic64_read(v);
		new = old - i;
	} while (atomic64_cmpxchg(v, old, new) != old);
	return new;
}

static inline void atomic64_set_mask(unsigned long long mask, atomic64_t *v)
{
	long long old, new;

	do {
		old = atomic64_read(v);
		new = old | mask;
	} while (atomic64_cmpxchg(v, old, new) != old);
}

static inline void atomic64_clear_mask(unsigned long long mask, atomic64_t *v)
{
	long long old, new;

	do {
		old = atomic64_read(v);
		new = old & mask;
	} while (atomic64_cmpxchg(v, old, new) != old);
}

#endif /* CONFIG_64BIT */

static inline int atomic64_add_unless(atomic64_t *v, long long a, long long u)
{
	long long c, old;

	c = atomic64_read(v);
	for (;;) {
		if (unlikely(c == u))
			break;
		old = atomic64_cmpxchg(v, c, c + a);
		if (likely(old == c))
			break;
		c = old;
	}
	return c != u;
}

static inline long long atomic64_dec_if_positive(atomic64_t *v)
{
	long long c, old, dec;

	c = atomic64_read(v);
	for (;;) {
		dec = c - 1;
		if (unlikely(dec < 0))
			break;
		old = atomic64_cmpxchg((v), c, dec);
		if (likely(old == c))
			break;
		c = old;
	}
	return dec;
}

#define atomic64_add(_i, _v)		atomic64_add_return(_i, _v)
#define atomic64_add_negative(_i, _v)	(atomic64_add_return(_i, _v) < 0)
#define atomic64_inc(_v)		atomic64_add_return(1, _v)
#define atomic64_inc_return(_v)		atomic64_add_return(1, _v)
#define atomic64_inc_and_test(_v)	(atomic64_add_return(1, _v) == 0)
#define atomic64_sub(_i, _v)		atomic64_sub_return(_i, _v)
#define atomic64_sub_and_test(_i, _v)	(atomic64_sub_return(_i, _v) == 0)
#define atomic64_dec(_v)		atomic64_sub_return(1, _v)
#define atomic64_dec_return(_v)		atomic64_sub_return(1, _v)
#define atomic64_dec_and_test(_v)	(atomic64_sub_return(1, _v) == 0)
#define atomic64_inc_not_zero(v)	atomic64_add_unless((v), 1, 0)

#define smp_mb__before_atomic_dec()	smp_mb()
#define smp_mb__after_atomic_dec()	smp_mb()
#define smp_mb__before_atomic_inc()	smp_mb()
#define smp_mb__after_atomic_inc()	smp_mb()

#include <asm-generic/atomic-long.h>

#endif /* __ARCH_S390_ATOMIC__  */