33  * Shared/exclusive locks.  This implementation attempts to ensure
109  * Returns true if an exclusive lock is recursed.  It assumes
110  * curthread currently has an exclusive lock.
419  * Try to do a non-blocking upgrade from a shared lock to an exclusive lock.
438 	 * Try to switch from one shared lock to an exclusive lock.  We need  in sx_try_upgrade_int()
440 	 * we will wake up the exclusive waiters when we drop the lock.  in sx_try_upgrade_int()
472  * Downgrade an unrecursed exclusive lock into a single shared lock.
493 	 * Try to switch from an exclusive lock with no shared waiters  in sx_downgrade_int()
495 	 * exclusive waiters, we don't need to lock the sleep queue so  in sx_downgrade_int()
618 	/* If we already hold an exclusive lock, then recurse. */  in _sx_xlock_hard()
778 		 * If an exclusive lock was released with both shared  in _sx_xlock_hard()
779 		 * and exclusive waiters and a shared waiter hasn't  in _sx_xlock_hard()
784 		 * as there are other exclusive waiters still.  If we  in _sx_xlock_hard()
837 		 * Since we have been unable to acquire the exclusive  in _sx_xlock_hard()
838 		 * lock and the exclusive waiters flag is set, we have  in _sx_xlock_hard()
955 	 * state of the exclusive waiters flag.  in _sx_xunlock_hard()
957 	 * starvation for the threads sleeping on the exclusive queue by giving  in _sx_xunlock_hard()
973 		    "exclusive");  in _sx_xunlock_hard()
997 	 * If no other thread has an exclusive lock then try to bump up  in __sx_slock_try()
1079 	 * shared locks once there is an exclusive waiter.  in _sx_slock_hard()
1151 		 * Some other thread already has an exclusive lock, so  in _sx_slock_hard()
1341 		 * Just wake up all the exclusive waiters.  in _sx_sunlock_hard()
1356 			    "exclusive queue", __func__, sx);  in _sx_sunlock_hard()
1430 		 * If some other thread has an exclusive lock or we  in _sx_assert()
1520 		db_printf("exclusive\n");  in db_show_sx()
1523 		db_printf("exclusive and shared\n");  in db_show_sx()
1533  * If the lock has an exclusive owner, return that in *ownerp.