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33 * version: DPDK.L.1.2.3-3
36 #ifndef _RTE_SPINLOCK_H_
37 #define _RTE_SPINLOCK_H_
44 * This file defines an API for read-write locks, which are implemented
45 * in an architecture-specific way. This kind of lock simply waits in
46 * a loop repeatedly checking until the lock becomes available.
48 * All locks must be initialised before use, and only initialised once.
56 #include <rte_lcore.h>
59 * The rte_spinlock_t type.
62 volatile int locked; /**< lock status 0 = unlocked, 1 = locked */
66 * A static spinlock initializer.
68 #define RTE_SPINLOCK_INITIALIZER { 0 }
71 * Initialize the spinlock to an unlocked state.
74 * A pointer to the spinlock.
77 rte_spinlock_init(rte_spinlock_t *sl)
86 * A pointer to the spinlock.
89 rte_spinlock_lock(rte_spinlock_t *sl)
94 "xchg %[locked], %[lv]\n"
103 : [locked] "=m" (sl->locked), [lv] "=q" (lock_val)
109 * Release the spinlock.
112 * A pointer to the spinlock.
115 rte_spinlock_unlock (rte_spinlock_t *sl)
119 "xchg %[locked], %[ulv]\n"
120 : [locked] "=m" (sl->locked), [ulv] "=q" (unlock_val)
121 : "[ulv]" (unlock_val)
126 * Try to take the lock.
129 * A pointer to the spinlock.
131 * 1 if the lock is successfully taken; 0 otherwise.
134 rte_spinlock_trylock (rte_spinlock_t *sl)
139 "xchg %[locked], %[lockval]"
140 : [locked] "=m" (sl->locked), [lockval] "=q" (lockval)
141 : "[lockval]" (lockval)
144 return (lockval == 0);
148 * Test if the lock is taken.
151 * A pointer to the spinlock.
153 * 1 if the lock is currently taken; 0 otherwise.
155 static inline int rte_spinlock_is_locked (rte_spinlock_t *sl)
161 * The rte_spinlock_recursive_t type.
164 rte_spinlock_t sl; /**< the actual spinlock */
165 volatile int user; /**< core id using lock, -1 for unused */
166 volatile int count; /**< count of time this lock has been called */
167 } rte_spinlock_recursive_t;
170 * A static recursive spinlock initializer.
172 #define RTE_SPINLOCK_RECURSIVE_INITIALIZER {RTE_SPINLOCK_INITIALIZER, -1, 0}
175 * Initialize the recursive spinlock to an unlocked state.
178 * A pointer to the recursive spinlock.
180 static inline void rte_spinlock_recursive_init(rte_spinlock_recursive_t *slr)
182 rte_spinlock_init(&slr->sl);
188 * Take the recursive spinlock.
191 * A pointer to the recursive spinlock.
193 static inline void rte_spinlock_recursive_lock(rte_spinlock_recursive_t *slr)
195 int id = rte_lcore_id();
197 if (slr->user != id) {
198 rte_spinlock_lock(&slr->sl);
204 * Release the recursive spinlock.
207 * A pointer to the recursive spinlock.
209 static inline void rte_spinlock_recursive_unlock(rte_spinlock_recursive_t *slr)
211 if (--(slr->count) == 0) {
213 rte_spinlock_unlock(&slr->sl);
219 * Try to take the recursive lock.
222 * A pointer to the recursive spinlock.
224 * 1 if the lock is successfully taken; 0 otherwise.
226 static inline int rte_spinlock_recursive_trylock(rte_spinlock_recursive_t *slr)
228 int id = rte_lcore_id();
230 if (slr->user != id) {
231 if (rte_spinlock_trylock(&slr->sl) == 0)
243 #endif /* _RTE_SPINLOCK_H_ */