1 // SPDX-License-Identifier: GPL-2.0-only
3  * PREEMPT_RT substitution for spin/rw_locks
8  * - Contrary to plain rtmutexes, spinlocks and rwlocks are state
11  *   during that time are redirected to the saved state so no wake up is
14  * - Non RT spin/rwlocks disable preemption and eventually interrupts.
29  * preserving. Take RCU nesting into account as spin/read/write_lock() can
40 	lockdep_assert(!current->pi_blocked_on);  in rtlock_lock()
49 	rtlock_lock(&lock->lock);  in __rt_spin_lock()
56 	spin_acquire(&lock->dep_map, 0, 0, _RET_IP_);  in rt_spin_lock()
64 	spin_acquire(&lock->dep_map, subclass, 0, _RET_IP_);  in rt_spin_lock_nested()
72 	spin_acquire_nest(&lock->dep_map, 0, 0, nest_lock, _RET_IP_);  in rt_spin_lock_nest_lock()
80 	spin_release(&lock->dep_map, _RET_IP_);  in rt_spin_unlock()
84 	if (unlikely(!rt_mutex_cmpxchg_release(&lock->lock, current, NULL)))  in rt_spin_unlock()
85 		rt_mutex_slowunlock(&lock->lock);  in rt_spin_unlock()
105 	if (unlikely(!rt_mutex_cmpxchg_acquire(&lock->lock, NULL, current)))  in __rt_spin_trylock()
106 		ret = rt_mutex_slowtrylock(&lock->lock);  in __rt_spin_trylock()
109 		spin_acquire(&lock->dep_map, 0, 1, _RET_IP_);  in __rt_spin_trylock()
141 	lockdep_init_map_type(&lock->dep_map, name, key, 0, LD_WAIT_CONFIG,  in __rt_spin_lock_init()
148  * RT-specific reader/writer locks
205 	ret = rwbase_read_trylock(&rwlock->rwbase);  in rt_read_trylock()
207 		rwlock_acquire_read(&rwlock->dep_map, 0, 1, _RET_IP_);  in rt_read_trylock()
219 	ret = rwbase_write_trylock(&rwlock->rwbase);  in rt_write_trylock()
221 		rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_);  in rt_write_trylock()
232 	rwlock_acquire_read(&rwlock->dep_map, 0, 0, _RET_IP_);  in rt_read_lock()
233 	rwbase_read_lock(&rwlock->rwbase, TASK_RTLOCK_WAIT);  in rt_read_lock()
242 	rwlock_acquire(&rwlock->dep_map, 0, 0, _RET_IP_);  in rt_write_lock()
243 	rwbase_write_lock(&rwlock->rwbase, TASK_RTLOCK_WAIT);  in rt_write_lock()
253 	rwlock_acquire(&rwlock->dep_map, subclass, 0, _RET_IP_);  in rt_write_lock_nested()
254 	rwbase_write_lock(&rwlock->rwbase, TASK_RTLOCK_WAIT);  in rt_write_lock_nested()
263 	rwlock_release(&rwlock->dep_map, _RET_IP_);  in rt_read_unlock()
266 	rwbase_read_unlock(&rwlock->rwbase, TASK_RTLOCK_WAIT);  in rt_read_unlock()
272 	rwlock_release(&rwlock->dep_map, _RET_IP_);  in rt_write_unlock()
275 	rwbase_write_unlock(&rwlock->rwbase);  in rt_write_unlock()
284 	lockdep_init_map_wait(&rwlock->dep_map, name, key, 0, LD_WAIT_CONFIG);  in __rt_rwlock_init()