summaryrefslogtreecommitdiff
path: root/include/asm-s390/atomic.h
blob: be6fefe223d614e6326c6f210a61a20caa51d0aa (plain) (blame)
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
#ifndef __ARCH_S390_ATOMIC__
#define __ARCH_S390_ATOMIC__

/*
 *  include/asm-s390/atomic.h
 *
 *  S390 version
 *    Copyright (C) 1999-2005 IBM Deutschland Entwicklung GmbH, IBM Corporation
 *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com),
 *               Denis Joseph Barrow,
 *		 Arnd Bergmann (arndb@de.ibm.com)
 *
 *  Derived from "include/asm-i386/bitops.h"
 *    Copyright (C) 1992, Linus Torvalds
 *
 */

/*
 * Atomic operations that C can't guarantee us.  Useful for
 * resource counting etc..
 * S390 uses 'Compare And Swap' for atomicity in SMP enviroment
 */

typedef struct {
	volatile int counter;
} __attribute__ ((aligned (4))) atomic_t;
#define ATOMIC_INIT(i)  { (i) }

#ifdef __KERNEL__

#define __CS_LOOP(ptr, op_val, op_string) ({				\
	typeof(ptr->counter) old_val, new_val;				\
        __asm__ __volatile__("   l     %0,0(%3)\n"			\
                             "0: lr    %1,%0\n"				\
                             op_string "  %1,%4\n"			\
                             "   cs    %0,%1,0(%3)\n"			\
                             "   jl    0b"				\
                             : "=&d" (old_val), "=&d" (new_val),	\
			       "=m" (((atomic_t *)(ptr))->counter)	\
			     : "a" (ptr), "d" (op_val),			\
			       "m" (((atomic_t *)(ptr))->counter)	\
			     : "cc", "memory" );			\
	new_val;							\
})
#define atomic_read(v)          ((v)->counter)
#define atomic_set(v,i)         (((v)->counter) = (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,%3,0(%2)\n"
			     : "+d" (old), "=m" (v->counter)
			     : "a" (v), "d" (new), "m" (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);
	while (c != u && (old = atomic_cmpxchg(v, c, c + a)) != c)
		c = old;
	return c != u;
}

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

#undef __CS_LOOP

#ifdef __s390x__
typedef struct {
	volatile long long counter;
} __attribute__ ((aligned (8))) atomic64_t;
#define ATOMIC64_INIT(i)  { (i) }

#define __CSG_LOOP(ptr, op_val, op_string) ({				\
	typeof(ptr->counter) old_val, new_val;				\
        __asm__ __volatile__("   lg    %0,0(%3)\n"			\
                             "0: lgr   %1,%0\n"				\
                             op_string "  %1,%4\n"			\
                             "   csg   %0,%1,0(%3)\n"			\
                             "   jl    0b"				\
                             : "=&d" (old_val), "=&d" (new_val),	\
			       "=m" (((atomic_t *)(ptr))->counter)	\
			     : "a" (ptr), "d" (op_val),			\
			       "m" (((atomic_t *)(ptr))->counter)	\
			     : "cc", "memory" );			\
	new_val;							\
})
#define atomic64_read(v)          ((v)->counter)
#define atomic64_set(v,i)         (((v)->counter) = (i))

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

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

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");
}

static __inline__ long long atomic64_cmpxchg(atomic64_t *v,
					     long long old, long long new)
{
	__asm__ __volatile__("  csg  %0,%3,0(%2)\n"
			     : "+d" (old), "=m" (v->counter)
			     : "a" (v), "d" (new), "m" (v->counter)
			     : "cc", "memory" );
	return old;
}

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

	c = atomic64_read(v);
	while (c != u && (old = atomic64_cmpxchg(v, c, c + a)) != c)
		c = old;
	return c != u;
}

#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0)

#undef __CSG_LOOP
#endif

#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.h>
#endif /* __KERNEL__ */
#endif /* __ARCH_S390_ATOMIC__  */