1 files changed, 27 insertions, 12 deletions

diff --git a/sys/kern/kern_rwlock.c b/sys/kern/kern_rwlock.c
index 85f1e6ace92..3641403f369 100644
--- a/sys/kern/kern_rwlock.c
+++ b/sys/kern/kern_rwlock.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_rwlock.c,v 1.10 2007/04/04 18:01:57 art Exp $	*/
+/*	$OpenBSD: kern_rwlock.c,v 1.11 2007/05/04 12:56:15 art Exp $	*/
 
 /*
  * Copyright (c) 2002, 2003 Artur Grabowski <art@openbsd.org>
@@ -31,6 +31,8 @@
 #include <sys/rwlock.h>
 #include <sys/limits.h>
 
+#include <machine/lock.h>
+
 /* XXX - temporary measure until proc0 is properly aligned */
 #define RW_PROC(p) (((long)p) & ~RWLOCK_MASK)
 
@@ -86,7 +88,7 @@ rw_enter_read(struct rwlock *rwl)
 	unsigned long owner = rwl->rwl_owner;
 
 	if (__predict_false((owner & RWLOCK_WRLOCK) ||
-	    rw_test_and_set(&rwl->rwl_owner, owner, owner + RWLOCK_READ_INCR)))
+	    rw_cas(&rwl->rwl_owner, owner, owner + RWLOCK_READ_INCR)))
 		rw_enter(rwl, RW_READ);
 }
 
@@ -95,7 +97,7 @@ rw_enter_write(struct rwlock *rwl)
 {
 	struct proc *p = curproc;
 
-	if (__predict_false(rw_test_and_set(&rwl->rwl_owner, 0,
+	if (__predict_false(rw_cas(&rwl->rwl_owner, 0,
 	    RW_PROC(p) | RWLOCK_WRLOCK)))
 		rw_enter(rwl, RW_WRITE);
 }
@@ -106,7 +108,7 @@ rw_exit_read(struct rwlock *rwl)
 	unsigned long owner = rwl->rwl_owner;
 
 	if (__predict_false((owner & RWLOCK_WAIT) ||
-	    rw_test_and_set(&rwl->rwl_owner, owner, owner - RWLOCK_READ_INCR)))
+	    rw_cas(&rwl->rwl_owner, owner, owner - RWLOCK_READ_INCR)))
 		rw_exit(rwl);
 }
 
@@ -116,12 +118,13 @@ rw_exit_write(struct rwlock *rwl)
 	unsigned long owner = rwl->rwl_owner;
 
 	if (__predict_false((owner & RWLOCK_WAIT) ||
-	    rw_test_and_set(&rwl->rwl_owner, owner, 0)))
+	    rw_cas(&rwl->rwl_owner, owner, 0)))
 		rw_exit(rwl);
 }
 
+#ifndef rw_cas
 int
-rw_test_and_set(volatile unsigned long *p, unsigned long o, unsigned long n)
+rw_cas(volatile unsigned long *p, unsigned long o, unsigned long n)
 {
 	if (*p != o)
 		return (1);
@@ -131,6 +134,8 @@ rw_test_and_set(volatile unsigned long *p, unsigned long o, unsigned long n)
 }
 #endif
 
+#endif
+
 #ifdef DIAGNOSTIC
 /*
  * Put the diagnostic functions here to keep the main code free
@@ -175,16 +180,17 @@ int
 rw_enter(struct rwlock *rwl, int flags)
 {
 	const struct rwlock_op *op;
+	struct sleep_state sls;
 	unsigned long inc, o;
-	int error, prio;
+	int error;
 
 	op = &rw_ops[flags & RW_OPMASK];
 
 	inc = op->inc + RW_PROC(curproc) * op->proc_mult;
 retry:
 	while (__predict_false(((o = rwl->rwl_owner) & op->check) != 0)) {
-		if (rw_test_and_set(&rwl->rwl_owner, o, o | op->wait_set))
-			continue;
+		unsigned long set = o | op->wait_set;
+		int do_sleep, prio;
 
 		prio = op->wait_prio;
 		if (flags & RW_INTR)
@@ -194,13 +200,22 @@ retry:
 
 		if (flags & RW_NOSLEEP)
 			return (EBUSY);
-		if ((error = tsleep(rwl, prio, rwl->rwl_name, 0)) != 0)
+
+		sleep_setup(&sls, rwl, op->wait_prio, rwl->rwl_name);
+		if (flags & RW_INTR)
+			sleep_setup_signal(&sls, op->wait_prio | PCATCH);
+
+		do_sleep = !rw_cas(&rwl->rwl_owner, o, set);
+
+		sleep_finish(&sls, do_sleep);
+		if ((flags & RW_INTR) &&
+		    (error = sleep_finish_signal(&sls)) != 0)
 			return (error);
 		if (flags & RW_SLEEPFAIL)
 			return (EAGAIN);
 	}
 
-	if (__predict_false(rw_test_and_set(&rwl->rwl_owner, o, o + inc)))
+	if (__predict_false(rw_cas(&rwl->rwl_owner, o, o + inc)))
 		goto retry;
 
 	/*
@@ -229,7 +244,7 @@ rw_exit(struct rwlock *rwl)
 		else
 			set = (owner - RWLOCK_READ_INCR) &
 				~(RWLOCK_WAIT|RWLOCK_WRWANT);
-	} while (rw_test_and_set(&rwl->rwl_owner, owner, set));
+	} while (rw_cas(&rwl->rwl_owner, owner, set));
 
 	if (owner & RWLOCK_WAIT)
 		wakeup(rwl);