forked from zeromq/zeromq2-x
/
atomic_counter.hpp
196 lines (171 loc) · 5.75 KB
/
atomic_counter.hpp
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
/*
Copyright (c) 2007-2010 iMatix Corporation
This file is part of 0MQ.
0MQ is free software; you can redistribute it and/or modify it under
the terms of the Lesser GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
0MQ is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
Lesser GNU General Public License for more details.
You should have received a copy of the Lesser GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ZMQ_ATOMIC_COUNTER_HPP_INCLUDED__
#define __ZMQ_ATOMIC_COUNTER_HPP_INCLUDED__
#include "stdint.hpp"
#include "platform.hpp"
#if defined ZMQ_FORCE_MUTEXES
#define ZMQ_ATOMIC_COUNTER_MUTEX
#elif (defined __i386__ || defined __x86_64__) && defined __GNUC__
#define ZMQ_ATOMIC_COUNTER_X86
#elif 0 && defined __sparc__ && defined __GNUC__
#define ZMQ_ATOMIC_COUNTER_SPARC
#elif defined ZMQ_HAVE_WINDOWS
#define ZMQ_ATOMIC_COUNTER_WINDOWS
#elif defined ZMQ_HAVE_SOLARIS
#define ZMQ_ATOMIC_COUNTER_SOLARIS
#else
#define ZMQ_ATOMIC_COUNTER_MUTEX
#endif
#if defined ZMQ_ATOMIC_COUNTER_MUTEX
#include "mutex.hpp"
#elif defined ZMQ_ATOMIC_COUNTER_WINDOWS
#include "windows.hpp"
#elif defined ZMQ_ATOMIC_COUNTER_SOLARIS
#include <atomic.h>
#endif
namespace zmq
{
// This class represents an integer that can be incremented/decremented
// in atomic fashion.
class atomic_counter_t
{
public:
typedef uint32_t integer_t;
inline atomic_counter_t (integer_t value_ = 0) :
value (value_)
{
}
inline ~atomic_counter_t ()
{
}
// Set counter value (not thread-safe).
inline void set (integer_t value_)
{
value = value_;
}
// Atomic addition. Returns the old value.
inline integer_t add (integer_t increment_)
{
integer_t old_value;
#if defined ZMQ_ATOMIC_COUNTER_WINDOWS
old_value = InterlockedExchangeAdd ((LONG*) &value, increment_);
#elif defined ZMQ_ATOMIC_COUNTER_SOLARIS
integer_t new_value = atomic_add_32_nv (&value, increment_);
old_value = new_value - increment_;
#elif defined ZMQ_ATOMIC_COUNTER_X86
__asm__ volatile (
"lock; xadd %0, %1 \n\t"
: "=r" (old_value), "=m" (value)
: "0" (increment_), "m" (value)
: "cc", "memory");
#elif defined ZMQ_ATOMIC_COUNTER_SPARC
integer_t tmp;
__asm__ volatile (
"ld [%4], %0 \n\t"
"1: \n\t"
"add %0, %3, %1 \n\t"
"cas [%4], %0, %1 \n\t"
"cmp %0, %1 \n\t"
"bne,a,pn %%icc, 1b \n\t"
"mov %1, %0 \n\t"
: "=&r" (old_value), "=&r" (tmp), "=m" (value)
: "r" (increment_), "r" (&value)
: "cc", "memory");
#elif defined ZMQ_ATOMIC_COUNTER_MUTEX
sync.lock ();
old_value = value;
value += increment_;
sync.unlock ();
#else
#error
#endif
return old_value;
}
// Atomic subtraction. Returns false if the counter drops to zero.
inline bool sub (integer_t decrement)
{
#if defined ZMQ_ATOMIC_COUNTER_WINDOWS
LONG delta = - ((LONG) decrement);
integer_t old = InterlockedExchangeAdd ((LONG*) &value, delta);
return old - decrement != 0;
#elif defined ZMQ_ATOMIC_COUNTER_SOLARIS
int32_t delta = - ((int32_t) decrement);
integer_t nv = atomic_add_32_nv (&value, delta);
return nv != 0;
#elif defined ZMQ_ATOMIC_COUNTER_X86
integer_t oldval = -decrement;
volatile integer_t *val = &value;
__asm__ volatile ("lock; xaddl %0,%1"
: "=r" (oldval), "=m" (*val)
: "0" (oldval), "m" (*val)
: "cc");
return oldval != decrement;
#elif defined ZMQ_ATOMIC_COUNTER_SPARC
volatile integer_t *val = &value;
integer_t tmp;
integer_t result;
__asm__ volatile(
"ld [%4], %1\n\t"
"1:\n\t"
"add %1, %0, %2\n\t"
"cas [%4], %1, %2\n\t"
"cmp %1, %2\n\t"
"bne,a,pn %%icc, 1b\n\t"
"mov %2, %1\n\t"
: "+r" (-decrement), "=&r" (tmp), "=&r" (result), "+m" (*val)
: "r" (val)
: "cc");
return result <= decrement;
#elif defined ZMQ_ATOMIC_COUNTER_MUTEX
sync.lock ();
value -= decrement;
bool result = value ? true : false;
sync.unlock ();
return result;
#else
#error
#endif
}
inline integer_t get ()
{
return value;
}
private:
volatile integer_t value;
#if defined ZMQ_ATOMIC_COUNTER_MUTEX
mutex_t sync;
#endif
atomic_counter_t (const atomic_counter_t&);
void operator = (const atomic_counter_t&);
};
}
// Remove macros local to this file.
#if defined ZMQ_ATOMIC_COUNTER_WINDOWS
#undef ZMQ_ATOMIC_COUNTER_WINDOWS
#endif
#if defined ZMQ_ATOMIC_COUNTER_SOLARIS
#undef ZMQ_ATOMIC_COUNTER_SOLARIS
#endif
#if defined ZMQ_ATOMIC_COUNTER_X86
#undef ZMQ_ATOMIC_COUNTER_X86
#endif
#if defined ZMQ_ATOMIC_COUNTER_SPARC
#undef ZMQ_ATOMIC_COUNTER_SPARC
#endif
#if defined ZMQ_ATOMIC_COUNTER_MUTEX
#undef ZMQ_ATOMIC_COUNTER_MUTEX
#endif
#endif