Split DIAGNOSTIC -> DIAGNOSTIC, INVARIANTS, and INVARIANT_SUPPORT as

discussed on -hackers.

Introduce 'KASSERT(assertion, ("panic message", args))' for simple
check + panic.

Reviewed by:	msmith

31 files changed, 253 insertions, 369 deletions

diff --git a/sys/conf/NOTES b/sys/conf/NOTES
index dca3ca3..27f1cea 100644
--- a/sys/conf/NOTES
+++ b/sys/conf/NOTES
@@ -2,7 +2,7 @@
 # LINT -- config file for checking all the sources, tries to pull in
 #	as much of the source tree as it can.
 #
-#	$Id: LINT,v 1.526 1999/01/01 08:09:57 peter Exp $
+#	$Id: LINT,v 1.527 1999/01/08 16:04:18 eivind Exp $
 #
 # NB: You probably don't want to try running a kernel built from this
 # file.  Instead, you should start from GENERIC, and add options from
@@ -291,12 +291,29 @@ options		GDB_REMOTE_CHAT
 options		KTRACE			#kernel tracing
 
 #
-# The DIAGNOSTIC option is used in a number of source files to enable
+# The INVARIANTS option is used in a number of source files to enable
 # extra sanity checking of internal structures.  This support is not
 # enabled by default because of the extra time it would take to check
 # for these conditions, which can only occur as a result of
 # programming errors.
 #
+options		INVARIANTS
+
+#
+# The INVARIANT_SUPPORT option makes us compile in support for
+# verifying some of the internal structures.  It is a prerequisite for
+# 'INVARIANTS', as enabling 'INVARIANTS' will make these functions be
+# called.  The intent is that you can set 'INVARIANTS' for single
+# source files (by changing the source file or specifying it on the
+# command line) if you have 'INVARIANT_SUPPORT' enabled.
+#
+options		INVARIANT_SUPPORT
+
+#
+# The DIAGNOSTIC option is used to enable extra debugging information
+# from some parts of the kernel.  As this makes everything more noisy,
+# it is disabled by default.
+#
 options		DIAGNOSTIC
 
 #
@@ -1867,6 +1884,7 @@ options		SHMSEG=9
 options		SI_DEBUG
 options		SIMPLELOCK_DEBUG
 options		SPX_HACK
+options		VFS_BIO_DEBUG
 
 # The 'dpt' driver provides support for DPT controllers (http://www.dpt.com/).
 # These have hardware RAID-{0,1,5} support, and do multi-initiator I/O.
diff --git a/sys/conf/options b/sys/conf/options
index c9c76fd..8e593d9 100644
--- a/sys/conf/options
+++ b/sys/conf/options
@@ -1,4 +1,4 @@
-#	$Id: options,v 1.112 1998/12/19 23:07:16 msmith Exp $
+#	$Id: options,v 1.113 1998/12/28 16:31:26 peter Exp $
 #
 #        On the handling of kernel options   
 # 
@@ -249,9 +249,13 @@ SI_DEBUG		opt_debug_si.h
 
 # These cause changes all over the kernel
 DEBUG			opt_global.h
+DEBUG_VFS_LOCKS		opt_global.h
 DIAGNOSTIC		opt_global.h
-SIMPLELOCK_DEBUG	opt_global.h
 ENABLE_VFS_IOOPT	opt_global.h
+INVARIANT_SUPPORT	opt_global.h
+INVARIANTS		opt_global.h
+SIMPLELOCK_DEBUG	opt_global.h
+VFS_BIO_DEBUG		opt_global.h
 
 # These are VM related options
 VM_KMEM_SIZE	opt_vm.h
diff --git a/sys/dev/snp/snp.c b/sys/dev/snp/snp.c
index c4b13e5..06f17dd 100644
--- a/sys/dev/snp/snp.c
+++ b/sys/dev/snp/snp.c
@@ -135,10 +135,8 @@ snpread(dev, uio, flag)
 	caddr_t         from;
 	char           *nbuf;
 
-#ifdef DIAGNOSTIC
-	if ((snp->snp_len + snp->snp_base) > snp->snp_blen)
-		panic("snoop buffer error");
-#endif
+	KASSERT(snp->snp_len + snp->snp_base <= snp->snp_blen,
+		("snoop buffer error"));
 
 	if (snp->snp_tty == NULL)
 		return (EIO);
@@ -212,10 +210,9 @@ snpin(snp, buf, n)
 	if (n == 0)
 		return 0;
 
-#ifdef DIAGNOSTIC
-	if (n < 0)
-		panic("bad snoop char count");
+	KASSERT(n > 0, ("negative snoop char count"));
 
+#ifdef DIAGNOSTIC
 	if (!(snp->snp_flags & SNOOP_OPEN)) {
 		printf("Snoop: data coming to closed device.\n");
 		return 0;
diff --git a/sys/i386/conf/LINT b/sys/i386/conf/LINT
index dca3ca3..27f1cea 100644
--- a/sys/i386/conf/LINT
+++ b/sys/i386/conf/LINT
@@ -2,7 +2,7 @@
 # LINT -- config file for checking all the sources, tries to pull in
 #	as much of the source tree as it can.
 #
-#	$Id: LINT,v 1.526 1999/01/01 08:09:57 peter Exp $
+#	$Id: LINT,v 1.527 1999/01/08 16:04:18 eivind Exp $
 #
 # NB: You probably don't want to try running a kernel built from this
 # file.  Instead, you should start from GENERIC, and add options from
@@ -291,12 +291,29 @@ options		GDB_REMOTE_CHAT
 options		KTRACE			#kernel tracing
 
 #
-# The DIAGNOSTIC option is used in a number of source files to enable
+# The INVARIANTS option is used in a number of source files to enable
 # extra sanity checking of internal structures.  This support is not
 # enabled by default because of the extra time it would take to check
 # for these conditions, which can only occur as a result of
 # programming errors.
 #
+options		INVARIANTS
+
+#
+# The INVARIANT_SUPPORT option makes us compile in support for
+# verifying some of the internal structures.  It is a prerequisite for
+# 'INVARIANTS', as enabling 'INVARIANTS' will make these functions be
+# called.  The intent is that you can set 'INVARIANTS' for single
+# source files (by changing the source file or specifying it on the
+# command line) if you have 'INVARIANT_SUPPORT' enabled.
+#
+options		INVARIANT_SUPPORT
+
+#
+# The DIAGNOSTIC option is used to enable extra debugging information
+# from some parts of the kernel.  As this makes everything more noisy,
+# it is disabled by default.
+#
 options		DIAGNOSTIC
 
 #
@@ -1867,6 +1884,7 @@ options		SHMSEG=9
 options		SI_DEBUG
 options		SIMPLELOCK_DEBUG
 options		SPX_HACK
+options		VFS_BIO_DEBUG
 
 # The 'dpt' driver provides support for DPT controllers (http://www.dpt.com/).
 # These have hardware RAID-{0,1,5} support, and do multi-initiator I/O.
diff --git a/sys/i386/conf/NOTES b/sys/i386/conf/NOTES
index dca3ca3..27f1cea 100644
--- a/sys/i386/conf/NOTES
+++ b/sys/i386/conf/NOTES
@@ -2,7 +2,7 @@
 # LINT -- config file for checking all the sources, tries to pull in
 #	as much of the source tree as it can.
 #
-#	$Id: LINT,v 1.526 1999/01/01 08:09:57 peter Exp $
+#	$Id: LINT,v 1.527 1999/01/08 16:04:18 eivind Exp $
 #
 # NB: You probably don't want to try running a kernel built from this
 # file.  Instead, you should start from GENERIC, and add options from
@@ -291,12 +291,29 @@ options		GDB_REMOTE_CHAT
 options		KTRACE			#kernel tracing
 
 #
-# The DIAGNOSTIC option is used in a number of source files to enable
+# The INVARIANTS option is used in a number of source files to enable
 # extra sanity checking of internal structures.  This support is not
 # enabled by default because of the extra time it would take to check
 # for these conditions, which can only occur as a result of
 # programming errors.
 #
+options		INVARIANTS
+
+#
+# The INVARIANT_SUPPORT option makes us compile in support for
+# verifying some of the internal structures.  It is a prerequisite for
+# 'INVARIANTS', as enabling 'INVARIANTS' will make these functions be
+# called.  The intent is that you can set 'INVARIANTS' for single
+# source files (by changing the source file or specifying it on the
+# command line) if you have 'INVARIANT_SUPPORT' enabled.
+#
+options		INVARIANT_SUPPORT
+
+#
+# The DIAGNOSTIC option is used to enable extra debugging information
+# from some parts of the kernel.  As this makes everything more noisy,
+# it is disabled by default.
+#
 options		DIAGNOSTIC
 
 #
@@ -1867,6 +1884,7 @@ options		SHMSEG=9
 options		SI_DEBUG
 options		SIMPLELOCK_DEBUG
 options		SPX_HACK
+options		VFS_BIO_DEBUG
 
 # The 'dpt' driver provides support for DPT controllers (http://www.dpt.com/).
 # These have hardware RAID-{0,1,5} support, and do multi-initiator I/O.
diff --git a/sys/kern/kern_descrip.c b/sys/kern/kern_descrip.c
index 8fc26b2..1d18a86 100644
--- a/sys/kern/kern_descrip.c
+++ b/sys/kern/kern_descrip.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_descrip.c	8.6 (Berkeley) 4/19/94
- * $Id: kern_descrip.c,v 1.56 1998/11/11 10:03:54 truckman Exp $
+ * $Id: kern_descrip.c,v 1.57 1998/11/11 10:55:56 truckman Exp $
  */
 
 #include "opt_compat.h"
@@ -845,7 +845,7 @@ ffree(fp)
 {
 	LIST_REMOVE(fp, f_list);
 	crfree(fp->f_cred);
-#ifdef DIAGNOSTIC
+#if defined(DIAGNOSTIC) || defined(INVARIANTS)
 	fp->f_count = 0;
 #endif
 	nfiles--;
diff --git a/sys/kern/kern_lock.c b/sys/kern/kern_lock.c
index f411f14..0bf31d0 100644
--- a/sys/kern/kern_lock.c
+++ b/sys/kern/kern_lock.c
@@ -38,7 +38,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_lock.c	8.18 (Berkeley) 5/21/95
- * $Id: kern_lock.c,v 1.19 1998/04/17 04:53:44 bde Exp $
+ * $Id: kern_lock.c,v 1.20 1998/11/26 18:50:23 eivind Exp $
  */
 
 #include "opt_lint.h"
@@ -83,14 +83,7 @@ sharelock(struct lock *lkp, int incr) {
 
 static LOCK_INLINE void
 shareunlock(struct lock *lkp, int decr) {
-#if defined(DIAGNOSTIC)
-	if (lkp->lk_sharecount < decr)
-#if defined(DDB)
-		Debugger("shareunlock: count < decr");
-#else
-		panic("shareunlock: count < decr");
-#endif
-#endif
+	KASSERT(lkp->lk_sharecount >= decr, ("shareunlock: count < decr"));
 
 	if (lkp->lk_sharecount == decr) {
 		lkp->lk_flags &= ~LK_SHARE_NONZERO;
diff --git a/sys/kern/kern_malloc.c b/sys/kern/kern_malloc.c
index 1ced96a..4cd7b73 100644
--- a/sys/kern/kern_malloc.c
+++ b/sys/kern/kern_malloc.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_malloc.c	8.3 (Berkeley) 1/4/94
- * $Id: kern_malloc.c,v 1.48 1998/10/25 17:44:51 phk Exp $
+ * $Id: kern_malloc.c,v 1.49 1998/11/10 08:46:24 peter Exp $
  */
 
 #include "opt_vm.h"
@@ -64,7 +64,7 @@ static char *kmembase;
 static char *kmemlimit;
 static int vm_kmem_size;
 
-#ifdef DIAGNOSTIC
+#if defined(INVARIANTS)
 /*
  * This structure provides a set of masks to catch unaligned frees.
  */
@@ -94,11 +94,11 @@ struct freelist {
 	long	spare1;
 	caddr_t	next;
 };
-#else /* !DIAGNOSTIC */
+#else /* !INVARIANTS */
 struct freelist {
 	caddr_t	next;
 };
-#endif /* DIAGNOSTIC */
+#endif /* INVARIANTS */
 
 /*
  * Allocate a block of memory
@@ -115,7 +115,7 @@ malloc(size, type, flags)
 	long indx, npg, allocsize;
 	int s;
 	caddr_t va, cp, savedlist;
-#ifdef DIAGNOSTIC
+#ifdef INVARIANTS
 	long *end, *lp;
 	int copysize;
 	char *savedtype;
@@ -138,7 +138,7 @@ malloc(size, type, flags)
 		tsleep((caddr_t)ksp, PSWP+2, type->ks_shortdesc, 0);
 	}
 	ksp->ks_size |= 1 << indx;
-#ifdef DIAGNOSTIC
+#ifdef INVARIANTS
 	copysize = 1 << indx < MAX_COPY ? 1 << indx : MAX_COPY;
 #endif
 	if (kbp->kb_next == NULL) {
@@ -174,7 +174,7 @@ malloc(size, type, flags)
 		kbp->kb_next = cp = va + (npg * PAGE_SIZE) - allocsize;
 		for (;;) {
 			freep = (struct freelist *)cp;
-#ifdef DIAGNOSTIC
+#ifdef INVARIANTS
 			/*
 			 * Copy in known text to detect modification
 			 * after freeing.
@@ -183,7 +183,7 @@ malloc(size, type, flags)
 			for (lp = (long *)cp; lp < end; lp++)
 				*lp = WEIRD_ADDR;
 			freep->type = M_FREE;
-#endif /* DIAGNOSTIC */
+#endif /* INVARIANTS */
 			if (cp <= va)
 				break;
 			cp -= allocsize;
@@ -195,7 +195,7 @@ malloc(size, type, flags)
 	}
 	va = kbp->kb_next;
 	kbp->kb_next = ((struct freelist *)va)->next;
-#ifdef DIAGNOSTIC
+#ifdef INVARIANTS
 	freep = (struct freelist *)va;
 	savedtype = (char *) type->ks_shortdesc;
 #if BYTE_ORDER == BIG_ENDIAN
@@ -219,7 +219,7 @@ malloc(size, type, flags)
 		break;
 	}
 	freep->spare0 = 0;
-#endif /* DIAGNOSTIC */
+#endif /* INVARIANTS */
 	kup = btokup(va);
 	if (kup->ku_indx != indx)
 		panic("malloc: wrong bucket");
@@ -251,7 +251,7 @@ free(addr, type)
 	register struct freelist *freep;
 	long size;
 	int s;
-#ifdef DIAGNOSTIC
+#ifdef INVARIANTS
 	struct freelist *fp;
 	long *end, *lp, alloc, copysize;
 #endif
@@ -260,16 +260,13 @@ free(addr, type)
 	if (!type->ks_next)
 		panic("freeing with unknown type (%s)", type->ks_shortdesc);
 
-#ifdef DIAGNOSTIC
-	if ((char *)addr < kmembase || (char *)addr >= kmemlimit) {
-		panic("free: address %p out of range", (void *)addr);
-	}
-#endif
+	KASSERT(kmembase <= (char *)addr && (char *)addr < kmemlimit,
+		("free: address %p out of range", (void *)addr));
 	kup = btokup(addr);
 	size = 1 << kup->ku_indx;
 	kbp = &bucket[kup->ku_indx];
 	s = splmem();
-#ifdef DIAGNOSTIC
+#ifdef INVARIANTS
 	/*
 	 * Check for returns of data that do not point to the
 	 * beginning of the allocation.
@@ -281,7 +278,7 @@ free(addr, type)
 	if (((uintptr_t)(void *)addr & alloc) != 0)
 		panic("free: unaligned addr %p, size %ld, type %s, mask %ld",
 		    (void *)addr, size, type->ks_shortdesc, alloc);
-#endif /* DIAGNOSTIC */
+#endif /* INVARIANTS */
 	if (size > MAXALLOCSAVE) {
 		kmem_free(kmem_map, (vm_offset_t)addr, ctob(kup->ku_pagecnt));
 		size = kup->ku_pagecnt << PAGE_SHIFT;
@@ -297,7 +294,7 @@ free(addr, type)
 		return;
 	}
 	freep = (struct freelist *)addr;
-#ifdef DIAGNOSTIC
+#ifdef INVARIANTS
 	/*
 	 * Check for multiple frees. Use a quick check to see if
 	 * it looks free before laboriously searching the freelist.
@@ -306,11 +303,9 @@ free(addr, type)
 		fp = (struct freelist *)kbp->kb_next;
 		while (fp) {
 			if (fp->spare0 != WEIRD_ADDR) {
-				printf("trashed free item %p\n", fp);
-				panic("free: free item modified");
+				panic("free: free item %p modified", fp);
 			} else if (addr == (caddr_t)fp) {
-				printf("multiple freed item %p\n", addr);
-				panic("free: multiple free");
+				panic("free: multiple freed item %p", addr);
 			}
 			fp = (struct freelist *)fp->next;
 		}
@@ -326,7 +321,7 @@ free(addr, type)
 	for (lp = (long *)addr; lp < end; lp++)
 		*lp = WEIRD_ADDR;
 	freep->type = type;
-#endif /* DIAGNOSTIC */
+#endif /* INVARIANTS */
 	kup->ku_freecnt++;
 	if (kup->ku_freecnt >= kbp->kb_elmpercl)
 		if (kup->ku_freecnt > kbp->kb_elmpercl)
diff --git a/sys/kern/kern_proc.c b/sys/kern/kern_proc.c
index 9f046a3..313a9e7 100644
--- a/sys/kern/kern_proc.c
+++ b/sys/kern/kern_proc.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_proc.c	8.7 (Berkeley) 2/14/95
- * $Id: kern_proc.c,v 1.39 1998/11/11 10:03:55 truckman Exp $
+ * $Id: kern_proc.c,v 1.40 1998/11/11 10:55:56 truckman Exp $
  */
 
 #include <sys/param.h>
@@ -195,22 +195,18 @@ enterpgrp(p, pgid, mksess)
 {
 	register struct pgrp *pgrp = pgfind(pgid);
 
-#ifdef DIAGNOSTIC
-	if (pgrp != NULL && mksess)	/* firewalls */
-		panic("enterpgrp: setsid into non-empty pgrp");
-	if (SESS_LEADER(p))
-		panic("enterpgrp: session leader attempted setpgrp");
-#endif
+	KASSERT(pgrp == NULL || !mksess,
+		("enterpgrp: setsid into non-empty pgrp"));
+	KASSERT(!SESS_LEADER(p),
+		("enterpgrp: session leader attempted setpgrp"));
 	if (pgrp == NULL) {
 		pid_t savepid = p->p_pid;
 		struct proc *np;
 		/*
 		 * new process group
 		 */
-#ifdef DIAGNOSTIC
-		if (p->p_pid != pgid)
-			panic("enterpgrp: new pgrp and pid != pgid");
-#endif
+		KASSERT(p->p_pid == pgid,
+			("enterpgrp: new pgrp and pid != pgid"));
 		MALLOC(pgrp, struct pgrp *, sizeof(struct pgrp), M_PGRP,
 		    M_WAITOK);
 		if ((np = pfind(savepid)) == NULL || np != p)
@@ -232,10 +228,8 @@ enterpgrp(p, pgid, mksess)
 			    sizeof(sess->s_login));
 			p->p_flag &= ~P_CONTROLT;
 			pgrp->pg_session = sess;
-#ifdef DIAGNOSTIC
-			if (p != curproc)
-				panic("enterpgrp: mksession and p != curproc");
-#endif
+			KASSERT(p == curproc,
+				("enterpgrp: mksession and p != curproc"));
 		} else {
 			pgrp->pg_session = p->p_session;
 			pgrp->pg_session->s_count++;
diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c
index dd4a431..e9a51d4 100644
--- a/sys/kern/kern_sig.c
+++ b/sys/kern/kern_sig.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_sig.c	8.7 (Berkeley) 4/18/94
- * $Id: kern_sig.c,v 1.50 1998/12/02 01:53:48 eivind Exp $
+ * $Id: kern_sig.c,v 1.51 1998/12/19 02:55:33 julian Exp $
  */
 
 #include "opt_compat.h"
@@ -1183,10 +1183,8 @@ postsig(signum)
 	register sig_t action;
 	int code, mask, returnmask;
 
-#ifdef DIAGNOSTIC
-	if (signum == 0)
-		panic("postsig");
-#endif
+	KASSERT(signum != 0, ("postsig"));
+
 	mask = sigmask(signum);
 	p->p_siglist &= ~mask;
 	action = ps->ps_sigact[signum];
@@ -1214,10 +1212,8 @@ postsig(signum)
 		/*
 		 * If we get here, the signal must be caught.
 		 */
-#ifdef DIAGNOSTIC
-		if (action == SIG_IGN || (p->p_sigmask & mask))
-			panic("postsig action");
-#endif
+		KASSERT(action != SIG_IGN && (p->p_sigmask & mask) == 0,
+			("postsig action"));
 		/*
 		 * Set the new mask value and also defer further
 		 * occurences of this signal.
diff --git a/sys/kern/kern_subr.c b/sys/kern/kern_subr.c
index 548cd20..d775d97 100644
--- a/sys/kern/kern_subr.c
+++ b/sys/kern/kern_subr.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_subr.c	8.3 (Berkeley) 1/21/94
- * $Id: kern_subr.c,v 1.21 1998/07/15 02:32:10 bde Exp $
+ * $Id: kern_subr.c,v 1.22 1998/08/04 09:21:04 phk Exp $
  */
 
 #include <sys/param.h>
@@ -61,12 +61,11 @@ uiomove(cp, n, uio)
 	u_int cnt;
 	int error;
 
-#ifdef DIAGNOSTIC
-	if (uio->uio_rw != UIO_READ && uio->uio_rw != UIO_WRITE)
-		panic("uiomove: mode");
-	if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc)
-		panic("uiomove proc");
-#endif
+	KASSERT(uio->uio_rw == UIO_READ || uio->uio_rw == UIO_WRITE,
+		("uiomove: mode"));
+	KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_procp == curproc,
+		("uiomove proc"));
+
 	while (n > 0 && uio->uio_resid) {
 		iov = uio->uio_iov;
 		cnt = iov->iov_len;
@@ -120,12 +119,11 @@ uiomoveco(cp, n, uio, obj)
 	u_int cnt;
 	int error;
 
-#ifdef DIAGNOSTIC
-	if (uio->uio_rw != UIO_READ && uio->uio_rw != UIO_WRITE)
-		panic("uiomove: mode");
-	if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc)
-		panic("uiomove proc");
-#endif
+	KASSERT(uio->uio_rw == UIO_READ || uio->uio_rw == UIO_WRITE,
+		("uiomoveco: mode"));
+	KASSERT(uio->uio_segflg != UIO_USERSPACE || uio->uio_procp == curproc,
+		("uiomoveco proc"));
+
 	while (n > 0 && uio->uio_resid) {
 		iov = uio->uio_iov;
 		cnt = iov->iov_len;
diff --git a/sys/kern/kern_synch.c b/sys/kern/kern_synch.c
index 17b2a94..3a9391d 100644
--- a/sys/kern/kern_synch.c
+++ b/sys/kern/kern_synch.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_synch.c	8.9 (Berkeley) 5/19/95
- * $Id: kern_synch.c,v 1.69 1998/11/27 11:44:22 dg Exp $
+ * $Id: kern_synch.c,v 1.70 1998/12/21 07:41:51 dillon Exp $
  */
 
 #include "opt_ktrace.h"
@@ -401,20 +401,11 @@ tsleep(ident, priority, wmesg, timo)
 		splx(s);
 		return (0);
 	}
-#ifdef DIAGNOSTIC
-	if(p == NULL) 
-		panic("tsleep1");
-	if (ident == NULL || p->p_stat != SRUN)
-		panic("tsleep");
-	/* XXX This is not exhaustive, just the most common case */
-#ifdef NOTDEF
-	/*
-	 * This can happen legitimately now with asleep()/await()
-	 */
-	if ((p->p_procq.tqe_prev != NULL) && (*p->p_procq.tqe_prev == p))
-		panic("sleeping process already on another queue");
-#endif
-#endif
+
+	KASSERT(p != NULL, ("tsleep1"));
+	KASSERT(ident != NULL && p->p_stat == SRUN,
+		("tsleep"));
+
 	/*
 	 * Process may be sitting on a slpque if asleep() was called, remove
 	 * it before re-adding.
@@ -706,16 +697,6 @@ wakeup(ident)
 	qp = &slpque[LOOKUP(ident)];
 restart:
 	for (p = qp->tqh_first; p != NULL; p = p->p_procq.tqe_next) {
-#ifdef DIAGNOSTIC
-#ifdef NOTDEF
-		/*
-		 * The process can legitimately be running now with 
-		 * asleep()/await().
-		 */
-		if (p->p_stat != SSLEEP && p->p_stat != SSTOP)
-			panic("wakeup");
-#endif
-#endif
 		if (p->p_wchan == ident) {
 			TAILQ_REMOVE(qp, p, p_procq);
 			p->p_wchan = 0;
@@ -757,16 +738,6 @@ wakeup_one(ident)
 	qp = &slpque[LOOKUP(ident)];
 
 	for (p = qp->tqh_first; p != NULL; p = p->p_procq.tqe_next) {
-#ifdef DIAGNOSTIC
-#ifdef NOTDEF
-		/*
-		 * The process can legitimately be running now with 
-		 * asleep()/await().
-		 */
-		if (p->p_stat != SSLEEP && p->p_stat != SSTOP)
-			panic("wakeup_one");
-#endif
-#endif
 		if (p->p_wchan == ident) {
 			TAILQ_REMOVE(qp, p, p_procq);
 			p->p_wchan = 0;
diff --git a/sys/kern/subr_autoconf.c b/sys/kern/subr_autoconf.c
index 8dfba39..9234732 100644
--- a/sys/kern/subr_autoconf.c
+++ b/sys/kern/subr_autoconf.c
@@ -41,7 +41,7 @@
  *
  *	@(#)subr_autoconf.c	8.1 (Berkeley) 6/10/93
  *
- * $Id: subr_autoconf.c,v 1.6 1997/11/18 12:43:41 bde Exp $
+ * $Id: subr_autoconf.c,v 1.7 1998/12/04 22:54:51 archie Exp $
  */
 
 #include <sys/param.h>
@@ -334,10 +334,8 @@ evcnt_attach(dev, name, ev)
 {
 	static struct evcnt **nextp = &allevents;
 
-#ifdef DIAGNOSTIC
-	if (strlen(name) >= sizeof(ev->ev_name))
-		panic("evcnt_attach");
-#endif
+	KASSERT(strlen(name) < sizeof(ev->ev_name), ("evcnt_attach"));
+
 	/* ev->ev_next = NULL; */
 	ev->ev_dev = dev;
 	/* ev->ev_count = 0; */
diff --git a/sys/kern/subr_rlist.c b/sys/kern/subr_rlist.c
index 33ac632..c3fdabf 100644
--- a/sys/kern/subr_rlist.c
+++ b/sys/kern/subr_rlist.c
@@ -54,7 +54,7 @@
  * functioning of this software, nor does the author assume any responsibility
  * for damages incurred with its use.
  *
- *	$Id: subr_rlist.c,v 1.26 1998/04/15 17:46:25 bde Exp $
+ *	$Id: subr_rlist.c,v 1.27 1998/08/05 14:06:04 dg Exp $
  */
 
 #include <sys/param.h>
@@ -137,16 +137,14 @@ rlist_free(rlh, start, end)
 	while (cur_rlp != NULL) {
 		if (start < cur_rlp->rl_start)
 			break;
-#ifdef DIAGNOSTIC
 		if (prev_rlp) {
-			if (prev_rlp->rl_end + 1 == cur_rlp->rl_start)
-				panic("rlist_free: missed coalesce opportunity");
-			if (prev_rlp->rl_end ==  cur_rlp->rl_start)
-				panic("rlist_free: entries overlap");
-			if (prev_rlp->rl_end > cur_rlp->rl_start)
-				panic("entries out of order");
+			KASSERT(prev_rlp->rl_end + 1 != cur_rlp->rl_start,
+				("rlist_free: missed coalesce opportunity"));
+			KASSERT(prev_rlp->rl_end != cur_rlp->rl_start,
+				("rlist_free: entries overlap"));
+			KASSERT(prev_rlp->rl_end <= cur_rlp->rl_start,
+				("entries out of order"));
 		}
-#endif
 		prev_rlp = cur_rlp;
 		cur_rlp = cur_rlp->rl_next;
 	}
diff --git a/sys/kern/tty.c b/sys/kern/tty.c
index 4d7dfac..1adf784 100644
--- a/sys/kern/tty.c
+++ b/sys/kern/tty.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)tty.c	8.8 (Berkeley) 1/21/94
- * $Id: tty.c,v 1.109 1998/12/07 07:59:20 ache Exp $
+ * $Id: tty.c,v 1.110 1998/12/08 10:22:07 bde Exp $
  */
 
 /*-
@@ -1310,10 +1310,8 @@ ttrstrt(tp_arg)
 	struct tty *tp;
 	int s;
 
-#ifdef DIAGNOSTIC
-	if (tp_arg == NULL)
-		panic("ttrstrt");
-#endif
+	KASSERT(tp_arg != NULL, ("ttrstrt"));
+
 	tp = tp_arg;
 	s = spltty();
 
diff --git a/sys/kern/tty_snoop.c b/sys/kern/tty_snoop.c
index c4b13e5..06f17dd 100644
--- a/sys/kern/tty_snoop.c
+++ b/sys/kern/tty_snoop.c
@@ -135,10 +135,8 @@ snpread(dev, uio, flag)
 	caddr_t         from;
 	char           *nbuf;
 
-#ifdef DIAGNOSTIC
-	if ((snp->snp_len + snp->snp_base) > snp->snp_blen)
-		panic("snoop buffer error");
-#endif
+	KASSERT(snp->snp_len + snp->snp_base <= snp->snp_blen,
+		("snoop buffer error"));
 
 	if (snp->snp_tty == NULL)
 		return (EIO);
@@ -212,10 +210,9 @@ snpin(snp, buf, n)
 	if (n == 0)
 		return 0;
 
-#ifdef DIAGNOSTIC
-	if (n < 0)
-		panic("bad snoop char count");
+	KASSERT(n > 0, ("negative snoop char count"));
 
+#ifdef DIAGNOSTIC
 	if (!(snp->snp_flags & SNOOP_OPEN)) {
 		printf("Snoop: data coming to closed device.\n");
 		return 0;
diff --git a/sys/kern/uipc_socket.c b/sys/kern/uipc_socket.c
index b1f64fe..f7fe5a7 100644
--- a/sys/kern/uipc_socket.c
+++ b/sys/kern/uipc_socket.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)uipc_socket.c	8.3 (Berkeley) 4/15/94
- *	$Id: uipc_socket.c,v 1.46 1998/11/11 10:03:56 truckman Exp $
+ *	$Id: uipc_socket.c,v 1.47 1998/12/07 21:58:29 archie Exp $
  */
 
 #include <sys/param.h>
@@ -637,10 +637,7 @@ restart:
 	    (so->so_rcv.sb_cc < so->so_rcv.sb_lowat ||
 	    ((flags & MSG_WAITALL) && uio->uio_resid <= so->so_rcv.sb_hiwat)) &&
 	    m->m_nextpkt == 0 && (pr->pr_flags & PR_ATOMIC) == 0)) {
-#ifdef DIAGNOSTIC
-		if (m == 0 && so->so_rcv.sb_cc)
-			panic("receive 1");
-#endif
+		KASSERT(m != 0 || !so->so_rcv.sb_cc, ("receive 1"));
 		if (so->so_error) {
 			if (m)
 				goto dontblock;
@@ -683,10 +680,7 @@ dontblock:
 		uio->uio_procp->p_stats->p_ru.ru_msgrcv++;
 	nextrecord = m->m_nextpkt;
 	if (pr->pr_flags & PR_ADDR) {
-#ifdef DIAGNOSTIC
-		if (m->m_type != MT_SONAME)
-			panic("receive 1a");
-#endif
+		KASSERT(m->m_type == MT_SONAME, ("receive 1a"));
 		orig_resid = 0;
 		if (psa)
 			*psa = dup_sockaddr(mtod(m, struct sockaddr *),
@@ -740,10 +734,9 @@ dontblock:
 				break;
 		} else if (type == MT_OOBDATA)
 			break;
-#ifdef DIAGNOSTIC
-		else if (m->m_type != MT_DATA && m->m_type != MT_HEADER)
-			panic("receive 3");
-#endif
+		else
+		    KASSERT(m->m_type == MT_DATA || m->m_type == MT_HEADER,
+			    ("receive 3"));
 		so->so_state &= ~SS_RCVATMARK;
 		len = uio->uio_resid;
 		if (so->so_oobmark && len > so->so_oobmark - offset)
diff --git a/sys/kern/vfs_bio.c b/sys/kern/vfs_bio.c
index a84f063..28d8a03 100644
--- a/sys/kern/vfs_bio.c
+++ b/sys/kern/vfs_bio.c
@@ -11,7 +11,7 @@
  * 2. Absolutely no warranty of function or purpose is made by the author
  *		John S. Dyson.
  *
- * $Id: vfs_bio.c,v 1.188 1998/12/22 14:43:58 luoqi Exp $
+ * $Id: vfs_bio.c,v 1.189 1998/12/22 18:57:30 dillon Exp $
  */
 
 /*
@@ -692,10 +692,7 @@ brelse(struct buf * bp)
 				int poffset = foff & PAGE_MASK;
 				int presid = resid > (PAGE_SIZE - poffset) ?
 					(PAGE_SIZE - poffset) : resid;
-#ifdef DIAGNOSTIC
-				if (presid < 0)
-					panic("brelse: extra page");
-#endif
+				KASSERT(presid >= 0, ("brelse: extra page"));
 				vm_page_set_invalid(m, poffset, presid);
 			}
 			resid -= PAGE_SIZE - (foff & PAGE_MASK);
@@ -1002,11 +999,8 @@ trytofreespace:
 		return (0);
 	}
 
-#if defined(DIAGNOSTIC)
-	if (bp->b_flags & B_BUSY) {
-		panic("getnewbuf: busy buffer on free list\n");
-	}
-#endif
+	KASSERT(!(bp->b_flags & B_BUSY), 
+		("getnewbuf: busy buffer on free list\n"));
 
 	/*
 	 * We are fairly aggressive about freeing VMIO buffers, but since
@@ -1460,10 +1454,8 @@ loop:
 			}
 		}
 
-#ifdef DIAGNOSTIC
-		if (bp->b_offset == NOOFFSET)
-			panic("getblk: no buffer offset");
-#endif
+		KASSERT(bp->b_offset != NOOFFSET, 
+			("getblk: no buffer offset"));
 
 		/*
 		 * Check that the constituted buffer really deserves for the
@@ -1711,10 +1703,8 @@ allocbuf(struct buf * bp, int size)
 					 * is the responsibility of vnode_pager_setsize
 					 */
 					m = bp->b_pages[i];
-#if defined(DIAGNOSTIC)
-					if (m == bogus_page)
-						panic("allocbuf: bogus page found");
-#endif
+					KASSERT(m != bogus_page,
+						("allocbuf: bogus page found"));
 					vm_page_sleep(m, "biodep", &m->busy);
 
 					bp->b_pages[i] = NULL;
@@ -1747,10 +1737,8 @@ allocbuf(struct buf * bp, int size)
 				tinc = PAGE_SIZE;
 
 				off = bp->b_offset;
-#ifdef DIAGNOSTIC
-				if (bp->b_offset == NOOFFSET)
-					panic("allocbuf: no buffer offset");
-#endif
+				KASSERT(bp->b_offset != NOOFFSET,
+					("allocbuf: no buffer offset"));
 
 				curbpnpages = bp->b_npages;
 		doretry:
@@ -1938,10 +1926,8 @@ biodone(register struct buf * bp)
 #endif
 
 		foff = bp->b_offset;
-#ifdef DIAGNOSTIC
-		if (bp->b_offset == NOOFFSET)
-			panic("biodone: no buffer offset");
-#endif
+		KASSERT(bp->b_offset != NOOFFSET,
+			("biodone: no buffer offset"));
 
 #if !defined(MAX_PERF)
 		if (!obj) {
@@ -2213,10 +2199,8 @@ vfs_busy_pages(struct buf * bp, int clear_modify)
 		vm_ooffset_t foff;
 
 		foff = bp->b_offset;
-#ifdef DIAGNOSTIC
-		if (bp->b_offset == NOOFFSET)
-			panic("vfs_busy_pages: no buffer offset");
-#endif
+		KASSERT(bp->b_offset != NOOFFSET,
+			("vfs_busy_pages: no buffer offset"));
 
 		vfs_setdirty(bp);
 
@@ -2266,10 +2250,8 @@ vfs_clean_pages(struct buf * bp)
 		vm_ooffset_t foff;
 		foff = bp->b_offset;
 
-#ifdef DIAGNOSTIC
-		if (bp->b_offset == NOOFFSET)
-			panic("vfs_clean_pages: no buffer offset");
-#endif
+		KASSERT(bp->b_offset != NOOFFSET,
+			("vfs_clean_pages: no buffer offset"));
 
 		for (i = 0; i < bp->b_npages; i++) {
 			vm_page_t m = bp->b_pages[i];
diff --git a/sys/kern/vfs_cluster.c b/sys/kern/vfs_cluster.c
index 1e4d7b8..07434ce 100644
--- a/sys/kern/vfs_cluster.c
+++ b/sys/kern/vfs_cluster.c
@@ -33,7 +33,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)vfs_cluster.c	8.7 (Berkeley) 2/13/94
- * $Id: vfs_cluster.c,v 1.74 1998/11/17 00:31:12 mckusick Exp $
+ * $Id: vfs_cluster.c,v 1.75 1998/12/05 06:12:14 mckusick Exp $
  */
 
 #include "opt_debug_cluster.h"
@@ -168,10 +168,8 @@ cluster_read(vp, filesize, lblkno, size, cred, totread, seqcount, bpp)
 	} else {
 		off_t firstread;
 		firstread = bp->b_offset;
-#ifdef DIAGNOSTIC
-		if (bp->b_offset == NOOFFSET)
-			panic("cluster_read: no buffer offset");
-#endif
+		KASSERT(bp->b_offset != NOOFFSET,
+			("cluster_read: no buffer offset"));
 		if (firstread + totread > filesize)
 			totread = filesize - firstread;
 		if (totread > size) {
@@ -312,11 +310,9 @@ cluster_rbuild(vp, filesize, lbn, blkno, size, run, fbp)
 	daddr_t bn;
 	int i, inc, j;
 
-#ifdef DIAGNOSTIC
-	if (size != vp->v_mount->mnt_stat.f_iosize)
-		panic("cluster_rbuild: size %ld != filesize %ld\n",
-		    size, vp->v_mount->mnt_stat.f_iosize);
-#endif
+	KASSERT(size == vp->v_mount->mnt_stat.f_iosize,
+		("cluster_rbuild: size %ld != filesize %ld\n",
+		    size, vp->v_mount->mnt_stat.f_iosize));
 	/*
 	 * avoid a division
 	 */
@@ -350,10 +346,8 @@ cluster_rbuild(vp, filesize, lbn, blkno, size, run, fbp)
 	bp->b_blkno = blkno;
 	bp->b_lblkno = lbn;
 	bp->b_offset = tbp->b_offset;
-#ifdef DIAGNOSTIC
-	if (bp->b_offset == NOOFFSET)
-		panic("cluster_rbuild: no buffer offset");
-#endif
+	KASSERT(bp->b_offset != NOOFFSET,
+		("cluster_rbuild: no buffer offset"));
 	pbgetvp(vp, bp);
 
 	TAILQ_INIT(&bp->b_cluster.cluster_head);
@@ -517,10 +511,7 @@ cluster_write(bp, filesize)
 	}
 	lbn = bp->b_lblkno;
 
-#ifdef DIAGNOSTIC
-	if (bp->b_offset == NOOFFSET)
-		panic("cluster_write: no buffer offset");
-#endif
+	KASSERT(bp->b_offset != NOOFFSET, ("cluster_write: no buffer offset"));
 
 	/* Initialize vnode to beginning of file. */
 	if (lbn == 0)
diff --git a/sys/kern/vfs_export.c b/sys/kern/vfs_export.c
index 0d5bbdc..92a8710 100644
--- a/sys/kern/vfs_export.c
+++ b/sys/kern/vfs_export.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)vfs_subr.c	8.31 (Berkeley) 5/26/95
- * $Id: vfs_subr.c,v 1.179 1999/01/05 18:12:29 eivind Exp $
+ * $Id: vfs_subr.c,v 1.180 1999/01/05 18:49:53 eivind Exp $
  */
 
 /*
@@ -466,7 +466,7 @@ getnewvnode(tag, mp, vops, vpp)
 			simple_unlock(&vp->v_interlock);
 		}
 
-#ifdef DIAGNOSTIC
+#ifdef INVARIANTS
 		{
 			int s;
 
@@ -796,10 +796,7 @@ bgetvp(vp, bp)
 {
 	int s;
 
-#if defined(DIAGNOSTIC)
-	if (bp->b_vp)
-		panic("bgetvp: not free");
-#endif
+	KASSERT(bp->b_vp == NULL, ("bgetvp: not free"));
 	vhold(vp);
 	bp->b_vp = vp;
 	if (vp->v_type == VBLK || vp->v_type == VCHR)
@@ -827,10 +824,7 @@ brelvp(bp)
 	struct buflists *listheadp;
 	int s;
 
-#if defined(DIAGNOSTIC)
-	if (bp->b_vp == (struct vnode *) 0)
-		panic("brelvp: NULL");
-#endif
+	KASSERT(bp->b_vp != NULL, ("brelvp: NULL"));
 
 	/*
 	 * Delete from old vnode list, if on one.
@@ -996,10 +990,8 @@ pbgetvp(vp, bp)
 	register struct vnode *vp;
 	register struct buf *bp;
 {
-#if defined(DIAGNOSTIC)
-	if (bp->b_vp)
-		panic("pbgetvp: not free");
-#endif
+	KASSERT(bp->b_vp == NULL, ("pbgetvp: not free"));
+
 	bp->b_vp = vp;
 	if (vp->v_type == VBLK || vp->v_type == VCHR)
 		bp->b_dev = vp->v_rdev;
@@ -1015,10 +1007,7 @@ pbrelvp(bp)
 	register struct buf *bp;
 {
 
-#if defined(DIAGNOSTIC)
-	if (bp->b_vp == (struct vnode *) 0)
-		panic("pbrelvp: NULL");
-#endif
+	KASSERT(bp->b_vp != NULL, ("pbrelvp: NULL"));
 
 	bp->b_vp = (struct vnode *) 0;
 }
@@ -1313,10 +1302,8 @@ vrele(vp)
 {
 	struct proc *p = curproc;	/* XXX */
 
-#ifdef DIAGNOSTIC
-	if (vp == NULL)
-		panic("vrele: null vp");
-#endif
+	KASSERT(vp, ("vrele: null vp"));
+
 	simple_lock(&vp->v_interlock);
 
 	if (vp->v_usecount > 1) {
@@ -1356,10 +1343,7 @@ vput(vp)
 {
 	struct proc *p = curproc;	/* XXX */
 
-#ifdef DIAGNOSTIC
-	if (vp == NULL)
-		panic("vput: null vp");
-#endif
+	KASSERT(vp != NULL, ("vput: null vp"));
 
 	simple_lock(&vp->v_interlock);
 
@@ -1646,10 +1630,7 @@ vop_revoke(ap)
 	struct vnode *vp, *vq;
 	struct proc *p = curproc;	/* XXX */
 
-#ifdef DIAGNOSTIC
-	if ((ap->a_flags & REVOKEALL) == 0)
-		panic("vop_revoke");
-#endif
+	KASSERT((ap->a_flags & REVOKEALL) != 0, ("vop_revoke"));
 
 	vp = ap->a_vp;
 	simple_lock(&vp->v_interlock);
diff --git a/sys/kern/vfs_lookup.c b/sys/kern/vfs_lookup.c
index 3a00557..e6e8a6f 100644
--- a/sys/kern/vfs_lookup.c
+++ b/sys/kern/vfs_lookup.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)vfs_lookup.c	8.4 (Berkeley) 2/16/94
- * $Id: vfs_lookup.c,v 1.28 1998/06/07 17:11:45 dfr Exp $
+ * $Id: vfs_lookup.c,v 1.29 1999/01/05 18:49:52 eivind Exp $
  */
 
 #include "opt_ktrace.h"
@@ -89,14 +89,11 @@ namei(ndp)
 	struct proc *p = cnp->cn_proc;
 
 	ndp->ni_cnd.cn_cred = ndp->ni_cnd.cn_proc->p_ucred;
-#ifdef DIAGNOSTIC
-	if (!cnp->cn_cred || !cnp->cn_proc)
-		panic ("namei: bad cred/proc");
-	if (cnp->cn_nameiop & (~OPMASK))
-		panic ("namei: nameiop contaminated with flags");
-	if (cnp->cn_flags & OPMASK)
-		panic ("namei: flags contaminated with nameiops");
-#endif
+	KASSERT(cnp->cn_cred && cnp->cn_proc, ("namei: bad cred/proc"));
+	KASSERT((cnp->cn_nameiop & (~OPMASK)) == 0,
+		("namei: nameiop contaminated with flags"));
+	KASSERT((cnp->cn_flags & OPMASK) == 0,
+		("namei: flags contaminated with nameiops"));
 	fdp = cnp->cn_proc->p_fd;
 
 	/*
@@ -418,10 +415,7 @@ unionlookup:
 	ndp->ni_vp = NULL;
 	ASSERT_VOP_LOCKED(dp, "lookup");
 	if (error = VOP_LOOKUP(dp, &ndp->ni_vp, cnp)) {
-#ifdef DIAGNOSTIC
-		if (ndp->ni_vp != NULL)
-			panic("leaf should be empty");
-#endif
+		KASSERT(ndp->ni_vp == NULL, ("leaf should be empty"));
 #ifdef NAMEI_DIAGNOSTIC
 		printf("not found\n");
 #endif
@@ -649,10 +643,7 @@ relookup(dvp, vpp, cnp)
 	 * We now have a segment name to search for, and a directory to search.
 	 */
 	if (error = VOP_LOOKUP(dp, vpp, cnp)) {
-#ifdef DIAGNOSTIC
-		if (*vpp != NULL)
-			panic("leaf should be empty");
-#endif
+		KASSERT(*vpp == NULL, ("leaf should be empty"));
 		if (error != EJUSTRETURN)
 			goto bad;
 		/*
@@ -675,13 +666,11 @@ relookup(dvp, vpp, cnp)
 	}
 	dp = *vpp;
 
-#ifdef DIAGNOSTIC
 	/*
 	 * Check for symbolic link
 	 */
-	if (dp->v_type == VLNK && (cnp->cn_flags & FOLLOW))
-		panic ("relookup: symlink found.\n");
-#endif
+	KASSERT(dp->v_type != VLNK || !(cnp->cn_flags & FOLLOW),
+		("relookup: symlink found.\n"));
 
 	/*
 	 * Disallow directory write attempts on read-only file systems.
diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c
index 0d5bbdc..92a8710 100644
--- a/sys/kern/vfs_subr.c
+++ b/sys/kern/vfs_subr.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)vfs_subr.c	8.31 (Berkeley) 5/26/95
- * $Id: vfs_subr.c,v 1.179 1999/01/05 18:12:29 eivind Exp $
+ * $Id: vfs_subr.c,v 1.180 1999/01/05 18:49:53 eivind Exp $
  */
 
 /*
@@ -466,7 +466,7 @@ getnewvnode(tag, mp, vops, vpp)
 			simple_unlock(&vp->v_interlock);
 		}
 
-#ifdef DIAGNOSTIC
+#ifdef INVARIANTS
 		{
 			int s;
 
@@ -796,10 +796,7 @@ bgetvp(vp, bp)
 {
 	int s;
 
-#if defined(DIAGNOSTIC)
-	if (bp->b_vp)
-		panic("bgetvp: not free");
-#endif
+	KASSERT(bp->b_vp == NULL, ("bgetvp: not free"));
 	vhold(vp);
 	bp->b_vp = vp;
 	if (vp->v_type == VBLK || vp->v_type == VCHR)
@@ -827,10 +824,7 @@ brelvp(bp)
 	struct buflists *listheadp;
 	int s;
 
-#if defined(DIAGNOSTIC)
-	if (bp->b_vp == (struct vnode *) 0)
-		panic("brelvp: NULL");
-#endif
+	KASSERT(bp->b_vp != NULL, ("brelvp: NULL"));
 
 	/*
 	 * Delete from old vnode list, if on one.
@@ -996,10 +990,8 @@ pbgetvp(vp, bp)
 	register struct vnode *vp;
 	register struct buf *bp;
 {
-#if defined(DIAGNOSTIC)
-	if (bp->b_vp)
-		panic("pbgetvp: not free");
-#endif
+	KASSERT(bp->b_vp == NULL, ("pbgetvp: not free"));
+
 	bp->b_vp = vp;
 	if (vp->v_type == VBLK || vp->v_type == VCHR)
 		bp->b_dev = vp->v_rdev;
@@ -1015,10 +1007,7 @@ pbrelvp(bp)
 	register struct buf *bp;
 {
 
-#if defined(DIAGNOSTIC)
-	if (bp->b_vp == (struct vnode *) 0)
-		panic("pbrelvp: NULL");
-#endif
+	KASSERT(bp->b_vp != NULL, ("pbrelvp: NULL"));
 
 	bp->b_vp = (struct vnode *) 0;
 }
@@ -1313,10 +1302,8 @@ vrele(vp)
 {
 	struct proc *p = curproc;	/* XXX */
 
-#ifdef DIAGNOSTIC
-	if (vp == NULL)
-		panic("vrele: null vp");
-#endif
+	KASSERT(vp, ("vrele: null vp"));
+
 	simple_lock(&vp->v_interlock);
 
 	if (vp->v_usecount > 1) {
@@ -1356,10 +1343,7 @@ vput(vp)
 {
 	struct proc *p = curproc;	/* XXX */
 
-#ifdef DIAGNOSTIC
-	if (vp == NULL)
-		panic("vput: null vp");
-#endif
+	KASSERT(vp != NULL, ("vput: null vp"));
 
 	simple_lock(&vp->v_interlock);
 
@@ -1646,10 +1630,7 @@ vop_revoke(ap)
 	struct vnode *vp, *vq;
 	struct proc *p = curproc;	/* XXX */
 
-#ifdef DIAGNOSTIC
-	if ((ap->a_flags & REVOKEALL) == 0)
-		panic("vop_revoke");
-#endif
+	KASSERT((ap->a_flags & REVOKEALL) != 0, ("vop_revoke"));
 
 	vp = ap->a_vp;
 	simple_lock(&vp->v_interlock);
diff --git a/sys/sys/systm.h b/sys/sys/systm.h
index 222d14b..158fa1d 100644
--- a/sys/sys/systm.h
+++ b/sys/sys/systm.h
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)systm.h	8.7 (Berkeley) 3/29/95
- * $Id: systm.h,v 1.79 1998/12/03 04:45:57 archie Exp $
+ * $Id: systm.h,v 1.80 1998/12/21 07:41:50 dillon Exp $
  */
 
 #ifndef _SYS_SYSTM_H_
@@ -76,6 +76,12 @@ extern struct vnode *swapdev_vp;/* vnode for swap device */
 extern int boothowto;		/* reboot flags, from console subsystem */
 extern int bootverbose;		/* nonzero to print verbose messages */
 
+#ifdef INVARIANTS		/* The option is always available */
+#define KASSERT(exp,msg) do { if (!(exp)) panic msg; } while(0)
+#else
+#define KASSERT(exp,msg)
+#endif
+
 /*
  * General function declarations.
  */
diff --git a/sys/vm/device_pager.c b/sys/vm/device_pager.c
index 4459b4c..a200b9c 100644
--- a/sys/vm/device_pager.c
+++ b/sys/vm/device_pager.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)device_pager.c	8.1 (Berkeley) 6/11/93
- * $Id: device_pager.c,v 1.35 1998/11/08 12:39:07 dfr Exp $
+ * $Id: device_pager.c,v 1.36 1998/12/07 21:58:50 archie Exp $
  */
 
 #include <sys/param.h>
@@ -208,10 +208,7 @@ dev_pager_getpages(object, m, count, reqpage)
 		panic("dev_pager_getpage: no map function");
 
 	paddr = pmap_phys_address((*mapfunc) ((dev_t) dev, (vm_offset_t) offset << PAGE_SHIFT, prot));
-#ifdef DIAGNOSTIC
-	if (paddr == -1)
-		panic("dev_pager_getpage: map function returns error");
-#endif
+	KASSERT(paddr != -1,("dev_pager_getpage: map function returns error"));
 	/*
 	 * Replace the passed in reqpage page with our own fake page and free up the
 	 * all of the original pages.
diff --git a/sys/vm/swap_pager.c b/sys/vm/swap_pager.c
index 3e2d0de..dff0490 100644
--- a/sys/vm/swap_pager.c
+++ b/sys/vm/swap_pager.c
@@ -39,7 +39,7 @@
  * from: Utah $Hdr: swap_pager.c 1.4 91/04/30$
  *
  *	@(#)swap_pager.c	8.9 (Berkeley) 3/21/94
- * $Id: swap_pager.c,v 1.104 1998/11/19 06:20:42 bde Exp $
+ * $Id: swap_pager.c,v 1.105 1998/12/29 22:53:51 dt Exp $
  */
 
 /*
@@ -1297,7 +1297,7 @@ swap_pager_putpages(object, m, count, sync, rtvals)
 			swb[i]->swb_locked--;
 	}
 
-#if defined(DIAGNOSTIC)
+#if defined(INVARIANTS)
 	for (i = firstidx; i < lastidx; i++) {
 		if (reqaddr[i] == SWB_EMPTY) {
 			printf("I/O to empty block???? -- pindex: %d, i: %d\n",
@@ -1348,11 +1348,9 @@ swap_pager_putpages(object, m, count, sync, rtvals)
 		}
 
 		spc = TAILQ_FIRST(&swap_pager_free);
-#if defined(DIAGNOSTIC)
-		if (spc == NULL)
-			panic("swap_pager_putpages: free queue is empty, %d expected\n",
-				swap_pager_free_count);
-#endif
+		KASSERT(spc,
+		    ("swap_pager_putpages: free queue is empty, %d expected\n",
+		    swap_pager_free_count));
 		TAILQ_REMOVE(&swap_pager_free, spc, spc_list);
 		swap_pager_free_count--;
 
diff --git a/sys/vm/vm_fault.c b/sys/vm/vm_fault.c
index 886833a..f1456b6 100644
--- a/sys/vm/vm_fault.c
+++ b/sys/vm/vm_fault.c
@@ -66,7 +66,7 @@
  * any improvements or extensions that they make and grant Carnegie the
  * rights to redistribute these changes.
  *
- * $Id: vm_fault.c,v 1.90 1998/10/28 13:37:02 dg Exp $
+ * $Id: vm_fault.c,v 1.91 1998/11/25 07:40:49 dg Exp $
  */
 
 /*
@@ -528,10 +528,8 @@ readrest:
 		}
 	}
 
-#if defined(DIAGNOSTIC)
-	if ((fs.m->flags & PG_BUSY) == 0)
-		panic("vm_fault: not busy after main loop");
-#endif
+	KASSERT((fs.m->flags & PG_BUSY) != 0,
+	    ("vm_fault: not busy after main loop"));
 
 	/*
 	 * PAGE HAS BEEN FOUND. [Loop invariant still holds -- the object lock
diff --git a/sys/vm/vm_object.c b/sys/vm/vm_object.c
index a79bb1b..a00e995 100644
--- a/sys/vm/vm_object.c
+++ b/sys/vm/vm_object.c
@@ -61,7 +61,7 @@
  * any improvements or extensions that they make and grant Carnegie the
  * rights to redistribute these changes.
  *
- * $Id: vm_object.c,v 1.135 1998/11/05 14:28:26 dg Exp $
+ * $Id: vm_object.c,v 1.136 1999/01/02 11:34:57 bde Exp $
  */
 
 /*
@@ -242,10 +242,8 @@ vm_object_reference(object)
 	if (object == NULL)
 		return;
 
-#if defined(DIAGNOSTIC)
-	if (object->flags & OBJ_DEAD)
-		panic("vm_object_reference: attempting to reference dead obj");
-#endif
+	KASSERT(!(object->flags & OBJ_DEAD),
+		("vm_object_reference: attempting to reference dead obj"));
 
 	object->ref_count++;
 	if (object->type == OBJT_VNODE) {
@@ -262,11 +260,10 @@ vm_object_vndeallocate(object)
 	vm_object_t object;
 {
 	struct vnode *vp = (struct vnode *) object->handle;
-#if defined(DIAGNOSTIC)
-	if (object->type != OBJT_VNODE)
-		panic("vm_object_vndeallocate: not a vnode object");
-	if (vp == NULL)
-		panic("vm_object_vndeallocate: missing vp");
+	KASSERT(object->type == OBJT_VNODE,
+		("vm_object_vndeallocate: not a vnode object"));
+	KASSERT(vp, ("vm_object_vndeallocate: missing vp"));
+#if defined(INVARIANTS)
 	if (object->ref_count == 0) {
 		vprint("vm_object_vndeallocate", vp);
 		panic("vm_object_vndeallocate: bad object reference count");
@@ -328,12 +325,11 @@ vm_object_deallocate(object)
 				vm_object_t robject;
 
 				robject = TAILQ_FIRST(&object->shadow_head);
-#if defined(DIAGNOSTIC)
-				if (robject == NULL)
-					panic("vm_object_deallocate: ref_count: %d,"
-						  " shadow_count: %d",
-						  object->ref_count, object->shadow_count);
-#endif
+				KASSERT(robject != NULL,
+					("vm_object_deallocate: ref_count: %d,"
+					 " shadow_count: %d",
+					 object->ref_count,
+					 object->shadow_count));
 				if ((robject->handle == NULL) &&
 				    (robject->type == OBJT_DEFAULT ||
 				     robject->type == OBJT_SWAP)) {
@@ -418,10 +414,8 @@ vm_object_terminate(object)
 	 */
 	vm_object_pip_wait(object, "objtrm");
 
-#if defined(DIAGNOSTIC)
-	if (object->paging_in_progress != 0)
-		panic("vm_object_terminate: pageout in progress");
-#endif
+	KASSERT(!object->paging_in_progress,
+		("vm_object_terminate: pageout in progress"));
 
 	/*
 	 * Clean and free the pages, as appropriate. All references to the
diff --git a/sys/vm/vm_page.c b/sys/vm/vm_page.c
index dec8452..08bfc60 100644
--- a/sys/vm/vm_page.c
+++ b/sys/vm/vm_page.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)vm_page.c	7.4 (Berkeley) 5/7/91
- *	$Id: vm_page.c,v 1.113 1998/11/11 15:07:57 dg Exp $
+ *	$Id: vm_page.c,v 1.114 1998/12/23 01:52:47 dillon Exp $
  */
 
 /*
@@ -870,11 +870,8 @@ vm_page_alloc(object, pindex, page_req)
 	int queue, qtype;
 	int s;
 
-#ifdef DIAGNOSTIC
-	m = vm_page_lookup(object, pindex);
-	if (m)
-		panic("vm_page_alloc: page already allocated");
-#endif
+	KASSERT(!vm_page_lookup(object, pindex),
+		("vm_page_alloc: page already allocated"));
 
 	if ((curproc == pageproc) && (page_req != VM_ALLOC_INTERRUPT)) {
 		page_req = VM_ALLOC_SYSTEM;
@@ -887,10 +884,7 @@ vm_page_alloc(object, pindex, page_req)
 	case VM_ALLOC_NORMAL:
 		if (cnt.v_free_count >= cnt.v_free_reserved) {
 			m = vm_page_select_free(object, pindex, PQ_FREE);
-#if defined(DIAGNOSTIC)
-			if (m == NULL)
-				panic("vm_page_alloc(NORMAL): missing page on free queue\n");
-#endif
+			KASSERT(m, ("vm_page_alloc(NORMAL): missing page on free queue\n"));
 		} else {
 			m = vm_page_select_cache(object, pindex);
 			if (m == NULL) {
@@ -909,10 +903,7 @@ vm_page_alloc(object, pindex, page_req)
 	case VM_ALLOC_ZERO:
 		if (cnt.v_free_count >= cnt.v_free_reserved) {
 			m = vm_page_select_free(object, pindex, PQ_ZERO);
-#if defined(DIAGNOSTIC)
-			if (m == NULL)
-				panic("vm_page_alloc(ZERO): missing page on free queue\n");
-#endif
+			KASSERT(m, ("vm_page_alloc(ZERO): missing page on free queue\n"));
 		} else {
 			m = vm_page_select_cache(object, pindex);
 			if (m == NULL) {
@@ -933,10 +924,7 @@ vm_page_alloc(object, pindex, page_req)
 		    ((cnt.v_cache_count == 0) &&
 		    (cnt.v_free_count >= cnt.v_interrupt_free_min))) {
 			m = vm_page_select_free(object, pindex, PQ_FREE);
-#if defined(DIAGNOSTIC)
-			if (m == NULL)
-				panic("vm_page_alloc(SYSTEM): missing page on free queue\n");
-#endif
+			KASSERT(m, ("vm_page_alloc(SYSTEM): missing page on free queue\n"));
 		} else {
 			m = vm_page_select_cache(object, pindex);
 			if (m == NULL) {
@@ -955,10 +943,7 @@ vm_page_alloc(object, pindex, page_req)
 	case VM_ALLOC_INTERRUPT:
 		if (cnt.v_free_count > 0) {
 			m = vm_page_select_free(object, pindex, PQ_FREE);
-#if defined(DIAGNOSTIC)
-			if (m == NULL)
-				panic("vm_page_alloc(INTERRUPT): missing page on free queue\n");
-#endif
+			KASSERT(m, ("vm_page_alloc(INTERRUPT): missing page on free queue\n"));
 		} else {
 			splx(s);
 			vm_pageout_deficit++;
diff --git a/sys/vm/vm_page.h b/sys/vm/vm_page.h
index 26231a2..3149391 100644
--- a/sys/vm/vm_page.h
+++ b/sys/vm/vm_page.h
@@ -61,7 +61,7 @@
  * any improvements or extensions that they make and grant Carnegie the
  * rights to redistribute these changes.
  *
- * $Id: vm_page.h,v 1.47 1998/10/21 14:46:42 dg Exp $
+ * $Id: vm_page.h,v 1.48 1998/10/28 13:37:02 dg Exp $
  */
 
 /*
@@ -391,12 +391,8 @@ vm_page_hold(vm_page_t mem)
 static __inline void
 vm_page_unhold(vm_page_t mem)
 {
-#ifdef DIAGNOSTIC
-	if (--mem->hold_count < 0)
-		panic("vm_page_unhold: hold count < 0!!!");
-#else
 	--mem->hold_count;
-#endif
+	KASSERT(mem->hold_count >= 0, ("vm_page_unhold: hold count < 0!!!"));
 }
 
 static __inline void
diff --git a/sys/vm/vm_zone.c b/sys/vm/vm_zone.c
index 3c52819..d90784e 100644
--- a/sys/vm/vm_zone.c
+++ b/sys/vm/vm_zone.c
@@ -11,7 +11,7 @@
  * 2. Absolutely no warranty of function or purpose is made by the author
  *	John S. Dyson.
  *
- * $Id: vm_zone.c,v 1.23 1998/10/31 17:21:31 peter Exp $
+ * $Id: vm_zone.c,v 1.24 1998/12/04 22:54:57 archie Exp $
  */
 
 #include <sys/param.h>
@@ -194,7 +194,7 @@ zbootinit(vm_zone_t z, char *name, int size, void *item, int nitems)
 	z->zitems = NULL;
 	for (i = 0; i < nitems; i++) {
 		((void **) item)[0] = z->zitems;
-#if defined(DIAGNOSTIC)
+#if defined(INVARIANTS)
 		((void **) item)[1] = (void *) ZENTRY_FREE;
 #endif
 		z->zitems = item;
@@ -357,7 +357,7 @@ _zget(vm_zone_t z)
 		nitems -= 1;
 		for (i = 0; i < nitems; i++) {
 			((void **) item)[0] = z->zitems;
-#if defined(DIAGNOSTIC)
+#if defined(INVARIANTS)
 			((void **) item)[1] = (void *) ZENTRY_FREE;
 #endif
 			z->zitems = item;
@@ -367,7 +367,7 @@ _zget(vm_zone_t z)
 	} else if (z->zfreecnt > 0) {
 		item = z->zitems;
 		z->zitems = ((void **) item)[0];
-#if defined(DIAGNOSTIC)
+#if defined(INVARIANTS)
 		if (((void **) item)[1] != (void *) ZENTRY_FREE)
 			zerror(ZONE_ERROR_NOTFREE);
 		((void **) item)[1] = 0;
@@ -432,7 +432,7 @@ sysctl_vm_zone SYSCTL_HANDLER_ARGS
 	return (0);
 }
 
-#if defined(DIAGNOSTIC)
+#if defined(INVARIANT_SUPPORT)
 void
 zerror(int error)
 {
diff --git a/sys/vm/vm_zone.h b/sys/vm/vm_zone.h
index 55c54d3..6b322f5 100644
--- a/sys/vm/vm_zone.h
+++ b/sys/vm/vm_zone.h
@@ -11,7 +11,7 @@
  * 2. Absolutely no warranty of function or purpose is made by the author
  *	John S. Dyson.
  *
- * $Id: vm_zone.c,v 1.20 1998/04/15 17:47:40 bde Exp $
+ * $Id: vm_zone.h,v 1.10 1998/04/25 04:50:03 dyson Exp $
  */
 
 #if !defined(_SYS_ZONE_H)
@@ -76,7 +76,7 @@ _zalloc(vm_zone_t z)
 {
 	void *item;
 
-#if defined(DIAGNOSTIC)
+#if defined(INVARIANTS)
 	if (z == 0)
 		zerror(ZONE_ERROR_INVALID);
 #endif
@@ -86,7 +86,7 @@ _zalloc(vm_zone_t z)
 
 	item = z->zitems;
 	z->zitems = ((void **) item)[0];
-#if defined(DIAGNOSTIC)
+#if defined(INVARIANTS)
 	if (((void **) item)[1] != (void *) ZENTRY_FREE)
 		zerror(ZONE_ERROR_NOTFREE);
 	((void **) item)[1] = 0;
@@ -101,7 +101,7 @@ static __inline__ void
 _zfree(vm_zone_t z, void *item)
 {
 	((void **) item)[0] = z->zitems;
-#if defined(DIAGNOSTIC)
+#if defined(INVARIANTS)
 	if (((void **) item)[1] == (void *) ZENTRY_FREE)
 		zerror(ZONE_ERROR_ALREADYFREE);
 	((void **) item)[1] = (void *) ZENTRY_FREE;