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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 * Test if hardware transactional memory (lock elision) is supported
151 * 1 if the hardware transactional memory is supported; 0 otherwise.
153 static inline int rte_tm_supported(void);
156 * Try to execute critical section in a hardware memory transaction,
157 * if it fails or not available take the spinlock.
159 * NOTE: An attempt to perform a HW I/O operation inside a hardware memory
160 * transaction always aborts the transaction since the CPU is not able to
161 * roll-back should the transaction fail. Therefore, hardware transactional
162 * locks are not advised to be used around rte_eth_rx_burst() and
163 * rte_eth_tx_burst() calls.
166 * A pointer to the spinlock.
169 rte_spinlock_lock_tm(rte_spinlock_t *sl);
172 * Commit hardware memory transaction or release the spinlock if
173 * the spinlock is used as a fall-back
176 * A pointer to the spinlock.
179 rte_spinlock_unlock_tm(rte_spinlock_t *sl);
182 * Try to execute critical section in a hardware memory transaction,
183 * if it fails or not available try to take the lock.
185 * NOTE: An attempt to perform a HW I/O operation inside a hardware memory
186 * transaction always aborts the transaction since the CPU is not able to
187 * roll-back should the transaction fail. Therefore, hardware transactional
188 * locks are not advised to be used around rte_eth_rx_burst() and
189 * rte_eth_tx_burst() calls.
192 * A pointer to the spinlock.
194 * 1 if the hardware memory transaction is successfully started
195 * or lock is successfully taken; 0 otherwise.
198 rte_spinlock_trylock_tm(rte_spinlock_t *sl);
201 * The rte_spinlock_recursive_t type.
204 rte_spinlock_t sl; /**< the actual spinlock */
205 volatile int user; /**< core id using lock, -1 for unused */
206 volatile int count; /**< count of time this lock has been called */
207 } rte_spinlock_recursive_t;
210 * A static recursive spinlock initializer.
212 #define RTE_SPINLOCK_RECURSIVE_INITIALIZER {RTE_SPINLOCK_INITIALIZER, -1, 0}
215 * Initialize the recursive spinlock to an unlocked state.
218 * A pointer to the recursive spinlock.
220 static inline void rte_spinlock_recursive_init(rte_spinlock_recursive_t *slr)
222 rte_spinlock_init(&slr->sl);
228 * Take the recursive spinlock.
231 * A pointer to the recursive spinlock.
233 static inline void rte_spinlock_recursive_lock(rte_spinlock_recursive_t *slr)
235 int id = rte_gettid();
237 if (slr->user != id) {
238 rte_spinlock_lock(&slr->sl);
244 * Release the recursive spinlock.
247 * A pointer to the recursive spinlock.
249 static inline void rte_spinlock_recursive_unlock(rte_spinlock_recursive_t *slr)
251 if (--(slr->count) == 0) {
253 rte_spinlock_unlock(&slr->sl);
259 * Try to take the recursive lock.
262 * A pointer to the recursive spinlock.
264 * 1 if the lock is successfully taken; 0 otherwise.
266 static inline int rte_spinlock_recursive_trylock(rte_spinlock_recursive_t *slr)
268 int id = rte_gettid();
270 if (slr->user != id) {
271 if (rte_spinlock_trylock(&slr->sl) == 0)
281 * Try to execute critical section in a hardware memory transaction,
282 * if it fails or not available take the recursive spinlocks
284 * NOTE: An attempt to perform a HW I/O operation inside a hardware memory
285 * transaction always aborts the transaction since the CPU is not able to
286 * roll-back should the transaction fail. Therefore, hardware transactional
287 * locks are not advised to be used around rte_eth_rx_burst() and
288 * rte_eth_tx_burst() calls.
291 * A pointer to the recursive spinlock.
293 static inline void rte_spinlock_recursive_lock_tm(
294 rte_spinlock_recursive_t *slr);
297 * Commit hardware memory transaction or release the recursive spinlock
298 * if the recursive spinlock is used as a fall-back
301 * A pointer to the recursive spinlock.
303 static inline void rte_spinlock_recursive_unlock_tm(
304 rte_spinlock_recursive_t *slr);
307 * Try to execute critical section in a hardware memory transaction,
308 * if it fails or not available try to take the recursive lock
310 * NOTE: An attempt to perform a HW I/O operation inside a hardware memory
311 * transaction always aborts the transaction since the CPU is not able to
312 * roll-back should the transaction fail. Therefore, hardware transactional
313 * locks are not advised to be used around rte_eth_rx_burst() and
314 * rte_eth_tx_burst() calls.
317 * A pointer to the recursive spinlock.
319 * 1 if the hardware memory transaction is successfully started
320 * or lock is successfully taken; 0 otherwise.
322 static inline int rte_spinlock_recursive_trylock_tm(
323 rte_spinlock_recursive_t *slr);
325 #endif /* _RTE_SPINLOCK_H_ */