1/* Licensed to the Apache Software Foundation (ASF) under one or more
2 * contributor license agreements.  See the NOTICE file distributed with
3 * this work for additional information regarding copyright ownership.
4 * The ASF licenses this file to You under the Apache License, Version 2.0
5 * (the "License"); you may not use this file except in compliance with
6 * the License.  You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "apr_arch_atomic.h"
18
19#ifdef USE_ATOMICS_S390
20
21APR_DECLARE(apr_status_t) apr_atomic_init(apr_pool_t *p)
22{
23    return APR_SUCCESS;
24}
25
26APR_DECLARE(apr_uint32_t) apr_atomic_read32(volatile apr_uint32_t *mem)
27{
28    return *mem;
29}
30
31APR_DECLARE(void) apr_atomic_set32(volatile apr_uint32_t *mem, apr_uint32_t val)
32{
33    *mem = val;
34}
35
36static APR_INLINE apr_uint32_t atomic_add(volatile apr_uint32_t *mem, apr_uint32_t val)
37{
38    apr_uint32_t prev = *mem, temp;
39
40    asm volatile ("loop_%=:\n"
41                  "    lr  %1,%0\n"
42                  "    alr %1,%3\n"
43                  "    cs  %0,%1,%2\n"
44                  "    jl  loop_%=\n"
45                  : "+d" (prev), "+d" (temp), "=Q" (*mem)
46                  : "d" (val), "m" (*mem)
47                  : "cc", "memory");
48
49    return prev;
50}
51
52APR_DECLARE(apr_uint32_t) apr_atomic_add32(volatile apr_uint32_t *mem, apr_uint32_t val)
53{
54    return atomic_add(mem, val);
55}
56
57APR_DECLARE(apr_uint32_t) apr_atomic_inc32(volatile apr_uint32_t *mem)
58{
59    return atomic_add(mem, 1);
60}
61
62static APR_INLINE apr_uint32_t atomic_sub(volatile apr_uint32_t *mem, apr_uint32_t val)
63{
64    apr_uint32_t prev = *mem, temp;
65
66    asm volatile ("loop_%=:\n"
67                  "    lr  %1,%0\n"
68                  "    slr %1,%3\n"
69                  "    cs  %0,%1,%2\n"
70                  "    jl  loop_%=\n"
71                  : "+d" (prev), "+d" (temp), "=Q" (*mem)
72                  : "d" (val), "m" (*mem)
73                  : "cc", "memory");
74
75    return temp;
76}
77
78APR_DECLARE(void) apr_atomic_sub32(volatile apr_uint32_t *mem, apr_uint32_t val)
79{
80    atomic_sub(mem, val);
81}
82
83APR_DECLARE(int) apr_atomic_dec32(volatile apr_uint32_t *mem)
84{
85    return atomic_sub(mem, 1);
86}
87
88APR_DECLARE(apr_uint32_t) apr_atomic_cas32(volatile apr_uint32_t *mem, apr_uint32_t with,
89                                           apr_uint32_t cmp)
90{
91    asm volatile ("    cs  %0,%2,%1\n"
92                  : "+d" (cmp), "=Q" (*mem)
93                  : "d" (with), "m" (*mem)
94                  : "cc", "memory");
95
96    return cmp;
97}
98
99APR_DECLARE(apr_uint32_t) apr_atomic_xchg32(volatile apr_uint32_t *mem, apr_uint32_t val)
100{
101    apr_uint32_t prev = *mem;
102
103    asm volatile ("loop_%=:\n"
104                  "    cs  %0,%2,%1\n"
105                  "    jl  loop_%=\n"
106                  : "+d" (prev), "=Q" (*mem)
107                  : "d" (val), "m" (*mem)
108                  : "cc", "memory");
109
110    return prev;
111}
112
113APR_DECLARE(void*) apr_atomic_casptr(volatile void **mem, void *with, const void *cmp)
114{
115    void *prev = (void *) cmp;
116#if APR_SIZEOF_VOIDP == 4
117    asm volatile ("    cs  %0,%2,%1\n"
118                  : "+d" (prev), "=Q" (*mem)
119                  : "d" (with), "m" (*mem)
120                  : "cc", "memory");
121#elif APR_SIZEOF_VOIDP == 8
122    asm volatile ("    csg %0,%2,%1\n"
123                  : "+d" (prev), "=Q" (*mem)
124                  : "d" (with), "m" (*mem)
125                  : "cc", "memory");
126#else
127#error APR_SIZEOF_VOIDP value not supported
128#endif
129    return prev;
130}
131
132APR_DECLARE(void*) apr_atomic_xchgptr(volatile void **mem, void *with)
133{
134    void *prev = (void *) *mem;
135#if APR_SIZEOF_VOIDP == 4
136    asm volatile ("loop_%=:\n"
137                  "    cs  %0,%2,%1\n"
138                  "    jl  loop_%=\n"
139                  : "+d" (prev), "=Q" (*mem)
140                  : "d" (with), "m" (*mem)
141                  : "cc", "memory");
142#elif APR_SIZEOF_VOIDP == 8
143    asm volatile ("loop_%=:\n"
144                  "    csg %0,%2,%1\n"
145                  "    jl  loop_%=\n"
146                  : "+d" (prev), "=Q" (*mem)
147                  : "d" (with), "m" (*mem)
148                  : "cc", "memory");
149#else
150#error APR_SIZEOF_VOIDP value not supported
151#endif
152    return prev;
153}
154
155#endif /* USE_ATOMICS_S390 */
156