DPDK  17.11.10
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 #include <rte_pause.h>
56 
62 typedef struct {
63  volatile int32_t cnt;
64 } rte_rwlock_t;
65 
69 #define RTE_RWLOCK_INITIALIZER { 0 }
70 
77 static inline void
79 {
80  rwl->cnt = 0;
81 }
82 
89 static inline void
91 {
92  int32_t x;
93  int success = 0;
94 
95  while (success == 0) {
96  x = rwl->cnt;
97  /* write lock is held */
98  if (x < 0) {
99  rte_pause();
100  continue;
101  }
102  success = rte_atomic32_cmpset((volatile uint32_t *)&rwl->cnt,
103  (uint32_t)x, (uint32_t)(x + 1));
104  }
105 }
106 
113 static inline void
115 {
116  rte_atomic32_dec((rte_atomic32_t *)(intptr_t)&rwl->cnt);
117 }
118 
125 static inline void
127 {
128  int32_t x;
129  int success = 0;
130 
131  while (success == 0) {
132  x = rwl->cnt;
133  /* a lock is held */
134  if (x != 0) {
135  rte_pause();
136  continue;
137  }
138  success = rte_atomic32_cmpset((volatile uint32_t *)&rwl->cnt,
139  0, (uint32_t)-1);
140  }
141 }
142 
149 static inline void
151 {
152  rte_atomic32_inc((rte_atomic32_t *)(intptr_t)&rwl->cnt);
153 }
154 
168 static inline void
170 
177 static inline void
179 
193 static inline void
195 
202 static inline void
204 
205 #ifdef __cplusplus
206 }
207 #endif
208 
209 #endif /* _RTE_RWLOCK_H_ */
static void rte_atomic32_inc(rte_atomic32_t *v)
static int rte_atomic32_cmpset(volatile uint32_t *dst, uint32_t exp, uint32_t src)
static void rte_rwlock_write_lock_tm(rte_rwlock_t *rwl)
static void rte_atomic32_dec(rte_atomic32_t *v)
static void rte_rwlock_read_lock(rte_rwlock_t *rwl)
Definition: rte_rwlock.h:90
static void rte_rwlock_read_lock_tm(rte_rwlock_t *rwl)
static void rte_rwlock_read_unlock(rte_rwlock_t *rwl)
Definition: rte_rwlock.h:114
static void rte_pause(void)
volatile int32_t cnt
Definition: rte_rwlock.h:63
static void rte_rwlock_write_unlock(rte_rwlock_t *rwl)
Definition: rte_rwlock.h:150
static void rte_rwlock_read_unlock_tm(rte_rwlock_t *rwl)
static void rte_rwlock_write_lock(rte_rwlock_t *rwl)
Definition: rte_rwlock.h:126
static void rte_rwlock_init(rte_rwlock_t *rwl)
Definition: rte_rwlock.h:78
static void rte_rwlock_write_unlock_tm(rte_rwlock_t *rwl)