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34 #ifndef _RTE_SPINLOCK_H_
35 #define _RTE_SPINLOCK_H_
42 * This file defines an API for read-write locks, which are implemented
43 * in an architecture-specific way. This kind of lock simply waits in
44 * a loop repeatedly checking until the lock becomes available.
46 * All locks must be initialised before use, and only initialised once.
50 #include <rte_lcore.h>
51 #ifdef RTE_FORCE_INTRINSICS
52 #include <rte_common.h>
56 * The rte_spinlock_t type.
59 volatile int locked; /**< lock status 0 = unlocked, 1 = locked */
63 * A static spinlock initializer.
65 #define RTE_SPINLOCK_INITIALIZER { 0 }
68 * Initialize the spinlock to an unlocked state.
71 * A pointer to the spinlock.
74 rte_spinlock_init(rte_spinlock_t *sl)
83 * A pointer to the spinlock.
86 rte_spinlock_lock(rte_spinlock_t *sl);
88 #ifdef RTE_FORCE_INTRINSICS
90 rte_spinlock_lock(rte_spinlock_t *sl)
92 while (__sync_lock_test_and_set(&sl->locked, 1))
99 * Release the spinlock.
102 * A pointer to the spinlock.
105 rte_spinlock_unlock (rte_spinlock_t *sl);
107 #ifdef RTE_FORCE_INTRINSICS
109 rte_spinlock_unlock (rte_spinlock_t *sl)
111 __sync_lock_release(&sl->locked);
116 * Try to take the lock.
119 * A pointer to the spinlock.
121 * 1 if the lock is successfully taken; 0 otherwise.
124 rte_spinlock_trylock (rte_spinlock_t *sl);
126 #ifdef RTE_FORCE_INTRINSICS
128 rte_spinlock_trylock (rte_spinlock_t *sl)
130 return (__sync_lock_test_and_set(&sl->locked,1) == 0);
135 * Test if the lock is taken.
138 * A pointer to the spinlock.
140 * 1 if the lock is currently taken; 0 otherwise.
142 static inline int rte_spinlock_is_locked (rte_spinlock_t *sl)
148 * The rte_spinlock_recursive_t type.
151 rte_spinlock_t sl; /**< the actual spinlock */
152 volatile int user; /**< core id using lock, -1 for unused */
153 volatile int count; /**< count of time this lock has been called */
154 } rte_spinlock_recursive_t;
157 * A static recursive spinlock initializer.
159 #define RTE_SPINLOCK_RECURSIVE_INITIALIZER {RTE_SPINLOCK_INITIALIZER, -1, 0}
162 * Initialize the recursive spinlock to an unlocked state.
165 * A pointer to the recursive spinlock.
167 static inline void rte_spinlock_recursive_init(rte_spinlock_recursive_t *slr)
169 rte_spinlock_init(&slr->sl);
175 * Take the recursive spinlock.
178 * A pointer to the recursive spinlock.
180 static inline void rte_spinlock_recursive_lock(rte_spinlock_recursive_t *slr)
182 int id = rte_lcore_id();
184 if (slr->user != id) {
185 rte_spinlock_lock(&slr->sl);
191 * Release the recursive spinlock.
194 * A pointer to the recursive spinlock.
196 static inline void rte_spinlock_recursive_unlock(rte_spinlock_recursive_t *slr)
198 if (--(slr->count) == 0) {
200 rte_spinlock_unlock(&slr->sl);
206 * Try to take the recursive lock.
209 * A pointer to the recursive spinlock.
211 * 1 if the lock is successfully taken; 0 otherwise.
213 static inline int rte_spinlock_recursive_trylock(rte_spinlock_recursive_t *slr)
215 int id = rte_lcore_id();
217 if (slr->user != id) {
218 if (rte_spinlock_trylock(&slr->sl) == 0)
226 #endif /* _RTE_SPINLOCK_H_ */