bsd/kern/kern_lockf.c

587 			 * lf_wakelock() always sets wakelock->lf_next to
1174 	struct lockf *wakelock;
1181 		wakelock = TAILQ_FIRST(&listhead->lf_blkhd);
1182 		TAILQ_REMOVE(&listhead->lf_blkhd, wakelock, lf_block);
1184 		wakelock->lf_next = NOLOCKF;
1187 			lf_print("lf_wakelock: awakening", wakelock);
1192 			 * move them to the wakelock list instead, and then
1196 				TAILQ_CONCAT(&wakelock->lf_blkhd, &listhead->lf_blkhd, lf_block);
1200 			        TAILQ_FOREACH(tlock, &wakelock->lf_blkhd, lf_block) {
1203 						panic("cycle in wakelock list");
1205 				        tlock->lf_next = wakelock;
1209 		wakeup(wakelock);