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35 #ifndef _RTE_SPINLOCK_H_
36 #define _RTE_SPINLOCK_H_
43 * This file defines an API for read-write locks, which are implemented
44 * in an architecture-specific way. This kind of lock simply waits in
45 * a loop repeatedly checking until the lock becomes available.
47 * All locks must be initialised before use, and only initialised once.
55 #include <rte_lcore.h>
58 * The rte_spinlock_t type.
61 volatile int locked; /**< lock status 0 = unlocked, 1 = locked */
65 * A static spinlock initializer.
67 #define RTE_SPINLOCK_INITIALIZER { 0 }
70 * Initialize the spinlock to an unlocked state.
73 * A pointer to the spinlock.
76 rte_spinlock_init(rte_spinlock_t *sl)
85 * A pointer to the spinlock.
88 rte_spinlock_lock(rte_spinlock_t *sl)
93 "xchg %[locked], %[lv]\n"
102 : [locked] "=m" (sl->locked), [lv] "=q" (lock_val)
108 * Release the spinlock.
111 * A pointer to the spinlock.
114 rte_spinlock_unlock (rte_spinlock_t *sl)
118 "xchg %[locked], %[ulv]\n"
119 : [locked] "=m" (sl->locked), [ulv] "=q" (unlock_val)
120 : "[ulv]" (unlock_val)
125 * Try to take the lock.
128 * A pointer to the spinlock.
130 * 1 if the lock is successfully taken; 0 otherwise.
133 rte_spinlock_trylock (rte_spinlock_t *sl)
138 "xchg %[locked], %[lockval]"
139 : [locked] "=m" (sl->locked), [lockval] "=q" (lockval)
140 : "[lockval]" (lockval)
143 return (lockval == 0);
147 * Test if the lock is taken.
150 * A pointer to the spinlock.
152 * 1 if the lock is currently taken; 0 otherwise.
154 static inline int rte_spinlock_is_locked (rte_spinlock_t *sl)
160 * The rte_spinlock_recursive_t type.
163 rte_spinlock_t sl; /**< the actual spinlock */
164 volatile int user; /**< core id using lock, -1 for unused */
165 volatile int count; /**< count of time this lock has been called */
166 } rte_spinlock_recursive_t;
169 * A static recursive spinlock initializer.
171 #define RTE_SPINLOCK_RECURSIVE_INITIALIZER {RTE_SPINLOCK_INITIALIZER, -1, 0}
174 * Initialize the recursive spinlock to an unlocked state.
177 * A pointer to the recursive spinlock.
179 static inline void rte_spinlock_recursive_init(rte_spinlock_recursive_t *slr)
181 rte_spinlock_init(&slr->sl);
187 * Take the recursive spinlock.
190 * A pointer to the recursive spinlock.
192 static inline void rte_spinlock_recursive_lock(rte_spinlock_recursive_t *slr)
194 int id = rte_lcore_id();
196 if (slr->user != id) {
197 rte_spinlock_lock(&slr->sl);
203 * Release the recursive spinlock.
206 * A pointer to the recursive spinlock.
208 static inline void rte_spinlock_recursive_unlock(rte_spinlock_recursive_t *slr)
210 if (--(slr->count) == 0) {
212 rte_spinlock_unlock(&slr->sl);
218 * Try to take the recursive lock.
221 * A pointer to the recursive spinlock.
223 * 1 if the lock is successfully taken; 0 otherwise.
225 static inline int rte_spinlock_recursive_trylock(rte_spinlock_recursive_t *slr)
227 int id = rte_lcore_id();
229 if (slr->user != id) {
230 if (rte_spinlock_trylock(&slr->sl) == 0)
242 #endif /* _RTE_SPINLOCK_H_ */