DPDK  16.04.0
rte_rwlock.h
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33 
34 #ifndef _RTE_RWLOCK_H_
35 #define _RTE_RWLOCK_H_
36 
49 #ifdef __cplusplus
50 extern "C" {
51 #endif
52 
53 #include <rte_common.h>
54 #include <rte_atomic.h>
55 
61 typedef struct {
62  volatile int32_t cnt;
63 } rte_rwlock_t;
64 
68 #define RTE_RWLOCK_INITIALIZER { 0 }
69 
76 static inline void
78 {
79  rwl->cnt = 0;
80 }
81 
88 static inline void
90 {
91  int32_t x;
92  int success = 0;
93 
94  while (success == 0) {
95  x = rwl->cnt;
96  /* write lock is held */
97  if (x < 0) {
98  rte_pause();
99  continue;
100  }
101  success = rte_atomic32_cmpset((volatile uint32_t *)&rwl->cnt,
102  x, x + 1);
103  }
104 }
105 
112 static inline void
114 {
115  rte_atomic32_dec((rte_atomic32_t *)(intptr_t)&rwl->cnt);
116 }
117 
124 static inline void
126 {
127  int32_t x;
128  int success = 0;
129 
130  while (success == 0) {
131  x = rwl->cnt;
132  /* a lock is held */
133  if (x != 0) {
134  rte_pause();
135  continue;
136  }
137  success = rte_atomic32_cmpset((volatile uint32_t *)&rwl->cnt,
138  0, -1);
139  }
140 }
141 
148 static inline void
150 {
151  rte_atomic32_inc((rte_atomic32_t *)(intptr_t)&rwl->cnt);
152 }
153 
167 static inline void
169 
176 static inline void
178 
192 static inline void
194 
201 static inline void
203 
204 #ifdef __cplusplus
205 }
206 #endif
207 
208 #endif /* _RTE_RWLOCK_H_ */