diff -ruN /cvs/sys_old/dev/musycc/musycc.c /usr/src/sys/dev/musycc/musycc.c
--- /cvs/sys_old/dev/musycc/musycc.c	Mon Dec 18 02:39:32 2000
+++ /usr/src/sys/dev/musycc/musycc.c	Mon Dec 18 22:20:39 2000
@@ -1193,8 +1193,8 @@
 		sc->mdt[ch][i].m = NULL;
 		sc->mdt[ch][i].data = 0;
 
-		MGETHDR(m, M_WAIT, MT_DATA);
-		MCLGET(m, M_WAIT);
+		MGETHDR(m, M_TRYWAIT, MT_DATA);
+		MCLGET(m, M_TRYWAIT);
 		sc->mdr[ch][i].m = m;
 		sc->mdr[ch][i].data = vtophys(m->m_data);
 		sc->mdr[ch][i].status = 1600; /* MTU */
diff -ruN /cvs/sys_old/kern/uipc_mbuf.c /usr/src/sys/kern/uipc_mbuf.c
--- /cvs/sys_old/kern/uipc_mbuf.c	Mon Dec 18 02:40:04 2000
+++ /usr/src/sys/kern/uipc_mbuf.c	Mon Dec 18 23:11:42 2000
@@ -206,8 +206,8 @@
 	nbytes = round_page(nmb * sizeof(union mext_refcnt));
 	mtx_exit(&mcntfree.m_mtx, MTX_DEF);
 	mtx_enter(&Giant, MTX_DEF);
-	if ((p = (caddr_t)kmem_malloc(mb_map, nbytes, how == M_WAIT ? M_WAIT :
-	    M_NOWAIT)) == NULL) {
+	if ((p = (caddr_t)kmem_malloc(mb_map, nbytes, how == M_TRYWAIT ?
+	    M_WAITOK : M_NOWAIT)) == NULL) {
 		mtx_exit(&Giant, MTX_DEF);
 		mtx_enter(&mcntfree.m_mtx, MTX_DEF); /* XXX: We must be	holding
 						             it going out. */
@@ -265,11 +265,11 @@
 	nbytes = round_page(nmb * MSIZE);
 
 	/* XXX: The letting go of the mmbfree lock here may eventually
-	   be moved to only be done for M_WAIT calls to kmem_malloc() */
+	   be moved to only be done for M_TRYWAIT calls to kmem_malloc() */
 	mtx_exit(&mmbfree.m_mtx, MTX_DEF);
 	mtx_enter(&Giant, MTX_DEF);
 	p = (caddr_t)kmem_malloc(mb_map, nbytes, M_NOWAIT);
-	if (p == 0 && how == M_WAIT) {
+	if (p == 0 && how == M_TRYWAIT) {
 		atomic_add_long(&mbstat.m_wait, 1);
 		p = (caddr_t)kmem_malloc(mb_map, nbytes, M_WAITOK);
 	}
@@ -302,8 +302,8 @@
 
 /*
  * Once the mb_map has been exhausted and if the call to the allocation macros
- * (or, in some cases, functions) is with M_WAIT, then it is necessary to rely
- * solely on reclaimed mbufs.
+ * (or, in some cases, functions) is with M_TRYWAIT, then it is necessary to
+ * rely solely on reclaimed mbufs.
  *
  * Here we request for the protocols to free up some resources and, if we
  * still cannot get anything, then we wait for an mbuf to be freed for a 
@@ -385,7 +385,7 @@
 	mtx_exit(&mclfree.m_mtx, MTX_DEF);
 	mtx_enter(&Giant, MTX_DEF);
 	p = (caddr_t)kmem_malloc(mb_map, ctob(npg),
-				 how != M_WAIT ? M_NOWAIT : M_WAITOK);
+				 how == M_TRYWAIT ? M_WAITOK : M_NOWAIT);
 	mtx_exit(&Giant, MTX_DEF);
 	ncl = ncl * PAGE_SIZE / MCLBYTES;
 	mtx_enter(&mclfree.m_mtx, MTX_DEF);
@@ -414,7 +414,7 @@
 
 /*
  * Once the mb_map submap has been exhausted and the allocation is called with
- * M_WAIT, we rely on the mclfree list. If nothing is free, we will
+ * M_TRYWAIT, we rely on the mclfree list. If nothing is free, we will
  * sleep for a designated amount of time (mbuf_wait) or until we're woken up
  * due to sudden mcluster availability.
  *
@@ -578,7 +578,7 @@
 /*
  * Make a copy of an mbuf chain starting "off0" bytes from the beginning,
  * continuing for "len" bytes.  If len is M_COPYALL, copy to end of mbuf.
- * The wait parameter is a choice of M_WAIT/M_DONTWAIT from caller.
+ * The wait parameter is a choice of M_TRYWAIT/M_DONTWAIT from caller.
  * Note that the copy is read-only, because clusters are not copied,
  * only their reference counts are incremented.
  */
diff -ruN /cvs/sys_old/kern/uipc_socket.c /usr/src/sys/kern/uipc_socket.c
--- /cvs/sys_old/kern/uipc_socket.c	Mon Dec 18 02:40:04 2000
+++ /usr/src/sys/kern/uipc_socket.c	Mon Dec 18 22:39:35 2000
@@ -558,7 +558,7 @@
 				top->m_flags |= M_EOR;
 		    } else do {
 			if (top == 0) {
-				MGETHDR(m, M_WAIT, MT_DATA);
+				MGETHDR(m, M_TRYWAIT, MT_DATA);
 				if (m == NULL) {
 					error = ENOBUFS;
 					goto release;
@@ -567,7 +567,7 @@
 				m->m_pkthdr.len = 0;
 				m->m_pkthdr.rcvif = (struct ifnet *)0;
 			} else {
-				MGET(m, M_WAIT, MT_DATA);
+				MGET(m, M_TRYWAIT, MT_DATA);
 				if (m == NULL) {
 					error = ENOBUFS;
 					goto release;
@@ -575,7 +575,7 @@
 				mlen = MLEN;
 			}
 			if (resid >= MINCLSIZE) {
-				MCLGET(m, M_WAIT);
+				MCLGET(m, M_TRYWAIT);
 				if ((m->m_flags & M_EXT) == 0)
 					goto nopages;
 				mlen = MCLBYTES;
@@ -695,7 +695,7 @@
 	else
 		flags = 0;
 	if (flags & MSG_OOB) {
-		m = m_get(M_WAIT, MT_DATA);
+		m = m_get(M_TRYWAIT, MT_DATA);
 		if (m == NULL)
 			return (ENOBUFS);
 		error = (*pr->pr_usrreqs->pru_rcvoob)(so, m, flags & MSG_PEEK);
@@ -887,7 +887,7 @@
 				moff += len;
 			else {
 				if (mp)
-					*mp = m_copym(m, 0, len, M_WAIT);
+					*mp = m_copym(m, 0, len, M_TRYWAIT);
 				m->m_data += len;
 				m->m_len -= len;
 				so->so_rcv.sb_cc -= len;
@@ -1390,11 +1390,11 @@
 	struct mbuf *m, *m_prev;
 	int sopt_size = sopt->sopt_valsize;
 
-	MGET(m, sopt->sopt_p ? M_WAIT : M_DONTWAIT, MT_DATA);
+	MGET(m, sopt->sopt_p ? M_TRYWAIT : M_DONTWAIT, MT_DATA);
 	if (m == 0)
 		return ENOBUFS;
 	if (sopt_size > MLEN) {
-		MCLGET(m, sopt->sopt_p ? M_WAIT : M_DONTWAIT);
+		MCLGET(m, sopt->sopt_p ? M_TRYWAIT : M_DONTWAIT);
 		if ((m->m_flags & M_EXT) == 0) {
 			m_free(m);
 			return ENOBUFS;
@@ -1408,13 +1408,13 @@
 	m_prev = m;
 
 	while (sopt_size) {
-		MGET(m, sopt->sopt_p ? M_WAIT : M_DONTWAIT, MT_DATA);
+		MGET(m, sopt->sopt_p ? M_TRYWAIT : M_DONTWAIT, MT_DATA);
 		if (m == 0) {
 			m_freem(*mp);
 			return ENOBUFS;
 		}
 		if (sopt_size > MLEN) {
-			MCLGET(m, sopt->sopt_p ? M_WAIT : M_DONTWAIT);
+			MCLGET(m, sopt->sopt_p ? M_TRYWAIT : M_DONTWAIT);
 			if ((m->m_flags & M_EXT) == 0) {
 				m_freem(*mp);
 				return ENOBUFS;
diff -ruN /cvs/sys_old/kern/uipc_syscalls.c /usr/src/sys/kern/uipc_syscalls.c
--- /cvs/sys_old/kern/uipc_syscalls.c	Mon Dec 18 02:40:04 2000
+++ /usr/src/sys/kern/uipc_syscalls.c	Mon Dec 18 22:39:37 2000
@@ -548,7 +548,7 @@
 		if (mp->msg_flags == MSG_COMPAT) {
 			register struct cmsghdr *cm;
 
-			M_PREPEND(control, sizeof(*cm), M_WAIT);
+			M_PREPEND(control, sizeof(*cm), M_TRYWAIT);
 			if (control == 0) {
 				error = ENOBUFS;
 				goto bad;
@@ -1331,7 +1331,7 @@
 #endif
 		return (EINVAL);
 	}
-	m = m_get(M_WAIT, type);
+	m = m_get(M_TRYWAIT, type);
 	if (m == NULL)
 		return (ENOBUFS);
 	m->m_len = buflen;
@@ -1702,7 +1702,7 @@
 		/*
 		 * Get an mbuf header and set it up as having external storage.
 		 */
-		MGETHDR(m, M_WAIT, MT_DATA);
+		MGETHDR(m, M_TRYWAIT, MT_DATA);
 		if (m == NULL) {
 			error = ENOBUFS;
 			sf_buf_free((void *)sf->kva, NULL);
diff -ruN /cvs/sys_old/kern/uipc_usrreq.c /usr/src/sys/kern/uipc_usrreq.c
--- /cvs/sys_old/kern/uipc_usrreq.c	Mon Dec 18 02:40:04 2000
+++ /usr/src/sys/kern/uipc_usrreq.c	Mon Dec 18 22:39:39 2000
@@ -1017,7 +1017,7 @@
 	if (newlen - control->m_len > M_TRAILINGSPACE(control)) {
 		if (control->m_flags & M_EXT)
 			return (E2BIG);
-		MCLGET(control, M_WAIT);
+		MCLGET(control, M_TRYWAIT);
 		if ((control->m_flags & M_EXT) == 0)
 			return (ENOBUFS);
 
diff -ruN /cvs/sys_old/net/bpf.c /usr/src/sys/net/bpf.c
--- /cvs/sys_old/net/bpf.c	Mon Dec 18 02:40:15 2000
+++ /usr/src/sys/net/bpf.c	Mon Dec 18 22:41:58 2000
@@ -231,12 +231,12 @@
 	if ((unsigned)len > MCLBYTES)
 		return (EIO);
 
-	MGETHDR(m, M_WAIT, MT_DATA);
+	MGETHDR(m, M_TRYWAIT, MT_DATA);
 	if (m == 0)
 		return (ENOBUFS);
 	if (len > MHLEN) {
 #if BSD >= 199103
-		MCLGET(m, M_WAIT);
+		MCLGET(m, M_TRYWAIT);
 		if ((m->m_flags & M_EXT) == 0) {
 #else
 		MCLGET(m);
diff -ruN /cvs/sys_old/net/bpf_compat.h /usr/src/sys/net/bpf_compat.h
--- /cvs/sys_old/net/bpf_compat.h	Mon Dec 18 02:40:13 2000
+++ /usr/src/sys/net/bpf_compat.h	Mon Dec 18 22:42:01 2000
@@ -46,7 +46,7 @@
  */
 #define malloc(size, type, canwait) bpf_alloc(size, canwait)
 #define free(cp, type) m_free(*(struct mbuf **)(cp - 8))
-#define M_WAITOK M_WAIT
+#define M_WAITOK M_TRYWAIT
 
 /* This mapping works for our purposes. */
 #define ERESTART EINTR
diff -ruN /cvs/sys_old/net/if_ef.c /usr/src/sys/net/if_ef.c
--- /cvs/sys_old/net/if_ef.c	Mon Dec 18 02:40:13 2000
+++ /usr/src/sys/net/if_ef.c	Mon Dec 18 22:42:19 2000
@@ -439,7 +439,7 @@
 		type = htons(m->m_pkthdr.len);
 		break;
 	    case ETHER_FT_8022:
-		M_PREPEND(m, ETHER_HDR_LEN + 3, M_WAIT);
+		M_PREPEND(m, ETHER_HDR_LEN + 3, M_TRYWAIT);
 		if (m == NULL) {
 			*mp = NULL;
 			return ENOBUFS;
@@ -462,7 +462,7 @@
 		*hlen += 3;
 		break;
 	    case ETHER_FT_SNAP:
-		M_PREPEND(m, 8, M_WAIT);
+		M_PREPEND(m, 8, M_TRYWAIT);
 		if (m == NULL) {
 			*mp = NULL;
 			return ENOBUFS;
diff -ruN /cvs/sys_old/net/if_ethersubr.c /usr/src/sys/net/if_ethersubr.c
--- /cvs/sys_old/net/if_ethersubr.c	Mon Dec 18 02:40:13 2000
+++ /usr/src/sys/net/if_ethersubr.c	Mon Dec 18 22:42:20 2000
@@ -221,7 +221,7 @@
 	    if ( aa->aa_flags & AFA_PHASE2 ) {
 		struct llc llc;
 
-		M_PREPEND(m, sizeof(struct llc), M_WAIT);
+		M_PREPEND(m, sizeof(struct llc), M_TRYWAIT);
 		llc.llc_dsap = llc.llc_ssap = LLC_SNAP_LSAP;
 		llc.llc_control = LLC_UI;
 		bcopy(at_org_code, llc.llc_snap_org_code, sizeof(at_org_code));
@@ -246,7 +246,7 @@
 			type = htons( m->m_pkthdr.len);
 			break;
 		case 0xe0e0: /* Novell 802.2 and Token-Ring */
-			M_PREPEND(m, 3, M_WAIT);
+			M_PREPEND(m, 3, M_TRYWAIT);
 			type = htons( m->m_pkthdr.len);
 			cp = mtod(m, u_char *);
 			*cp++ = 0xE0;
diff -ruN /cvs/sys_old/net/if_fddisubr.c /usr/src/sys/net/if_fddisubr.c
--- /cvs/sys_old/net/if_fddisubr.c	Mon Dec 18 02:40:13 2000
+++ /usr/src/sys/net/if_fddisubr.c	Mon Dec 18 22:42:23 2000
@@ -213,7 +213,7 @@
 	    if (aa->aa_flags & AFA_PHASE2) {
 		struct llc llc;
 
-		M_PREPEND(m, sizeof(struct llc), M_WAIT);
+		M_PREPEND(m, sizeof(struct llc), M_TRYWAIT);
 		if (m == 0)
 			senderr(ENOBUFS);
 		llc.llc_dsap = llc.llc_ssap = LLC_SNAP_LSAP;
diff -ruN /cvs/sys_old/net/if_gif.c /usr/src/sys/net/if_gif.c
--- /cvs/sys_old/net/if_gif.c	Mon Dec 18 02:40:13 2000
+++ /usr/src/sys/net/if_gif.c	Mon Dec 18 23:07:50 2000
@@ -118,7 +118,7 @@
 	register int i;
 
 	ngif = NGIF;
-	gif = sc = malloc (ngif * sizeof(struct gif_softc), M_DEVBUF, M_WAIT);
+	gif = sc = malloc (ngif * sizeof(struct gif_softc), M_DEVBUF, M_WAITOK);
 	bzero(sc, ngif * sizeof(struct gif_softc));
 	for (i = 0; i < ngif; sc++, i++) {
 		sc->gif_if.if_name = "gif";
diff -ruN /cvs/sys_old/net/if_sl.c /usr/src/sys/net/if_sl.c
--- /cvs/sys_old/net/if_sl.c	Mon Dec 18 02:40:14 2000
+++ /usr/src/sys/net/if_sl.c	Mon Dec 18 22:42:39 2000
@@ -253,9 +253,9 @@
 
 	MALLOC(sc, struct sl_softc *, sizeof(*sc), M_SL, M_WAITOK | M_ZERO);
 
-	m = m_gethdr(M_WAIT, MT_DATA);
+	m = m_gethdr(M_TRYWAIT, MT_DATA);
 	if (m != NULL) {
-		MCLGET(m, M_WAIT);
+		MCLGET(m, M_TRYWAIT);
 		if ((m->m_flags & M_EXT) == 0) {
 			m_free(m);
 			m = NULL;
diff -ruN /cvs/sys_old/net/if_stf.c /usr/src/sys/net/if_stf.c
--- /cvs/sys_old/net/if_stf.c	Mon Dec 18 02:40:14 2000
+++ /usr/src/sys/net/if_stf.c	Mon Dec 18 23:08:05 2000
@@ -173,7 +173,7 @@
 	const struct encaptab *p;
 
 	nstf = NSTF;
-	stf = malloc(nstf * sizeof(struct stf_softc), M_DEVBUF, M_WAIT);
+	stf = malloc(nstf * sizeof(struct stf_softc), M_DEVBUF, M_WAITOK);
 	bzero(stf, nstf * sizeof(struct stf_softc));
 	sc = stf;
 
diff -ruN /cvs/sys_old/net/ppp_tty.c /usr/src/sys/net/ppp_tty.c
--- /cvs/sys_old/net/ppp_tty.c	Mon Dec 18 02:40:14 2000
+++ /usr/src/sys/net/ppp_tty.c	Mon Dec 18 22:43:12 2000
@@ -391,7 +391,7 @@
 
     s = spltty();
     for (mp = &m0; uio->uio_resid; mp = &m->m_next) {
-	MGET(m, M_WAIT, MT_DATA);
+	MGET(m, M_TRYWAIT, MT_DATA);
 	if ((*mp = m) == NULL) {
 	    m_freem(m0);
 	    splx(s);
diff -ruN /cvs/sys_old/netatalk/aarp.c /usr/src/sys/netatalk/aarp.c
--- /cvs/sys_old/netatalk/aarp.c	Mon Dec 18 02:40:15 2000
+++ /usr/src/sys/netatalk/aarp.c	Mon Dec 18 22:43:28 2000
@@ -161,7 +161,7 @@
 	bcopy((caddr_t)atmulticastaddr, (caddr_t)eh->ether_dhost,
 		sizeof( eh->ether_dhost ));
 	eh->ether_type = htons(sizeof(struct llc) + sizeof(struct ether_aarp));
-	M_PREPEND( m, sizeof( struct llc ), M_WAIT );
+	M_PREPEND( m, sizeof( struct llc ), M_TRYWAIT );
 	llc = mtod( m, struct llc *);
 	llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
 	llc->llc_control = LLC_UI;
@@ -571,7 +571,7 @@
 		sizeof( eh->ether_dhost ));
 	eh->ether_type = htons( sizeof( struct llc ) +
 		sizeof( struct ether_aarp ));
-	M_PREPEND( m, sizeof( struct llc ), M_WAIT );
+	M_PREPEND( m, sizeof( struct llc ), M_TRYWAIT );
 	llc = mtod( m, struct llc *);
 	llc->llc_dsap = llc->llc_ssap = LLC_SNAP_LSAP;
 	llc->llc_control = LLC_UI;
diff -ruN /cvs/sys_old/netatalk/ddp_output.c /usr/src/sys/netatalk/ddp_output.c
--- /cvs/sys_old/netatalk/ddp_output.c	Mon Dec 18 02:40:15 2000
+++ /usr/src/sys/netatalk/ddp_output.c	Mon Dec 18 22:43:40 2000
@@ -48,7 +48,7 @@
     struct ddpehdr	*deh;
     struct ddpcb *ddp = sotoddpcb( so );
 
-    M_PREPEND( m, sizeof( struct ddpehdr ), M_WAIT );
+    M_PREPEND( m, sizeof( struct ddpehdr ), M_TRYWAIT );
 
     deh = mtod( m, struct ddpehdr *);
     deh->deh_pad = 0;
@@ -189,7 +189,7 @@
      * packets end up poorly aligned due to the three byte elap header.
      */
     if ( !(aa->aa_flags & AFA_PHASE2) ) {
-	MGET( m0, M_WAIT, MT_HEADER );
+	MGET( m0, M_TRYWAIT, MT_HEADER );
 	if ( m0 == 0 ) {
 	    m_freem( m );
 	    printf("ddp_route: no buffers\n");
diff -ruN /cvs/sys_old/netatm/port.h /usr/src/sys/netatm/port.h
--- /cvs/sys_old/netatm/port.h	Mon Dec 18 02:40:18 2000
+++ /usr/src/sys/netatm/port.h	Mon Dec 18 22:43:57 2000
@@ -210,7 +210,7 @@
 #include <sys/mbuf.h>
 typedef struct mbuf	KBuffer;
 
-#define	KB_F_WAIT	M_WAIT
+#define	KB_F_WAIT	M_TRYWAIT
 #define	KB_F_NOWAIT	M_DONTWAIT
 
 #define	KB_T_HEADER	MT_HEADER
diff -ruN /cvs/sys_old/netinet/ip_output.c /usr/src/sys/netinet/ip_output.c
--- /cvs/sys_old/netinet/ip_output.c	Mon Dec 18 02:40:20 2000
+++ /usr/src/sys/netinet/ip_output.c	Mon Dec 18 22:47:41 2000
@@ -1115,7 +1115,7 @@
 				error = EMSGSIZE;
 				break;
 			}
-			MGET(m, sopt->sopt_p ? M_WAIT : M_DONTWAIT, MT_HEADER);
+			MGET(m, sopt->sopt_p ? M_TRYWAIT : M_DONTWAIT, MT_HEADER);
 			if (m == 0) {
 				error = ENOBUFS;
 				break;
diff -ruN /cvs/sys_old/netinet/raw_ip.c /usr/src/sys/netinet/raw_ip.c
--- /cvs/sys_old/netinet/raw_ip.c	Mon Dec 18 02:40:20 2000
+++ /usr/src/sys/netinet/raw_ip.c	Mon Dec 18 22:47:53 2000
@@ -195,7 +195,7 @@
 			m_freem(m);
 			return(EMSGSIZE);
 		}
-		M_PREPEND(m, sizeof(struct ip), M_WAIT);
+		M_PREPEND(m, sizeof(struct ip), M_TRYWAIT);
 		ip = mtod(m, struct ip *);
 		ip->ip_tos = 0;
 		ip->ip_off = 0;
diff -ruN /cvs/sys_old/netinet6/ip6_fw.c /usr/src/sys/netinet6/ip6_fw.c
--- /cvs/sys_old/netinet6/ip6_fw.c	Mon Dec 18 02:40:21 2000
+++ /usr/src/sys/netinet6/ip6_fw.c	Mon Dec 18 22:48:50 2000
@@ -1045,11 +1045,11 @@
 
 	if (stage == IPV6_FW_GET) {
 		struct ip6_fw_chain *fcp = ip6_fw_chain.lh_first;
-		*mm = m = m_get(M_WAIT, MT_DATA); /* XXX */
+		*mm = m = m_get(M_TRYWAIT, MT_DATA); /* XXX */
 		if (!m)
 			return(ENOBUFS);
 		if (sizeof *(fcp->rule) > MLEN) {
-			MCLGET(m, M_WAIT);
+			MCLGET(m, M_TRYWAIT);
 			if ((m->m_flags & M_EXT) == 0) {
 				m_free(m);
 				return(ENOBUFS);
@@ -1058,14 +1058,14 @@
 		for (; fcp; fcp = fcp->chain.le_next) {
 			memcpy(m->m_data, fcp->rule, sizeof *(fcp->rule));
 			m->m_len = sizeof *(fcp->rule);
-			m->m_next = m_get(M_WAIT, MT_DATA); /* XXX */
+			m->m_next = m_get(M_TRYWAIT, MT_DATA); /* XXX */
 			if (!m->m_next) {
 				m_freem(*mm);
 				return(ENOBUFS);
 			}
 			m = m->m_next;
 			if (sizeof *(fcp->rule) > MLEN) {
-				MCLGET(m, M_WAIT);
+				MCLGET(m, M_TRYWAIT);
 				if ((m->m_flags & M_EXT) == 0) {
 					m_freem(*mm);
 					return(ENOBUFS);
diff -ruN /cvs/sys_old/netinet6/ip6_output.c /usr/src/sys/netinet6/ip6_output.c
--- /cvs/sys_old/netinet6/ip6_output.c	Mon Dec 18 02:40:22 2000
+++ /usr/src/sys/netinet6/ip6_output.c	Mon Dec 18 22:48:56 2000
@@ -1330,7 +1330,7 @@
 					break;
 				}
 				/* XXX */
-				MGET(m, sopt->sopt_p ? M_WAIT : M_DONTWAIT, MT_HEADER);
+				MGET(m, sopt->sopt_p ? M_TRYWAIT : M_DONTWAIT, MT_HEADER);
 				if (m == 0) {
 					error = ENOBUFS;
 					break;
@@ -1920,7 +1920,7 @@
 {
 	u_int *hlim, *loop, *ifindex;
 
-	*mp = m_get(M_WAIT, MT_HEADER);		/*XXX*/
+	*mp = m_get(M_TRYWAIT, MT_HEADER);		/*XXX*/
 
 	switch (optname) {
 
diff -ruN /cvs/sys_old/netinet6/raw_ip6.c /usr/src/sys/netinet6/raw_ip6.c
--- /cvs/sys_old/netinet6/raw_ip6.c	Mon Dec 18 02:40:23 2000
+++ /usr/src/sys/netinet6/raw_ip6.c	Mon Dec 18 22:49:18 2000
@@ -333,7 +333,7 @@
 		code = icmp6->icmp6_code;
 	}
 
-	M_PREPEND(m, sizeof(*ip6), M_WAIT);
+	M_PREPEND(m, sizeof(*ip6), M_TRYWAIT);
 	ip6 = mtod(m, struct ip6_hdr *);
 
 	/*
diff -ruN /cvs/sys_old/netipx/spx_usrreq.c /usr/src/sys/netipx/spx_usrreq.c
--- /cvs/sys_old/netipx/spx_usrreq.c	Mon Dec 18 02:40:23 2000
+++ /usr/src/sys/netipx/spx_usrreq.c	Mon Dec 18 22:49:47 2000
@@ -751,7 +751,7 @@
 					 * from usrreq(), so it is OK to
 					 * block.
 					 */
-					m = m_copym(m0, 0, mtu, M_WAIT);
+					m = m_copym(m0, 0, mtu, M_TRYWAIT);
 					if (cb->s_flags & SF_NEWCALL) {
 					    struct mbuf *mm = m;
 					    spx_newchecks[7]++;
diff -ruN /cvs/sys_old/netncp/ncp_rq.c /usr/src/sys/netncp/ncp_rq.c
--- /cvs/sys_old/netncp/ncp_rq.c	Mon Dec 18 02:40:24 2000
+++ /usr/src/sys/netncp/ncp_rq.c	Mon Dec 18 22:50:22 2000
@@ -60,9 +60,9 @@
 	bzero(rqp, sizeof(*rqp));
 	rqp->p = p;
 	rqp->cred = cred;
-	m = m_gethdr(M_WAIT, MT_DATA);
+	m = m_gethdr(M_TRYWAIT, MT_DATA);
 	if (m == NULL) 
-		return ENOBUFS;		/* if M_WAIT ? */
+		return ENOBUFS;		/* if M_TRYWAIT ? */
 	m->m_pkthdr.rcvif = NULL;
 	rqp->rq = rqp->mrq = m;
 	rqp->rp = NULL;
@@ -106,9 +106,9 @@
 	mp = top;
 	while (rest > 0) {
 /*	NCPSDEBUG("%d\n",rest);*/
-		m = m_get(M_WAIT, MT_DATA);
+		m = m_get(M_TRYWAIT, MT_DATA);
 		if (rest > MINCLSIZE) {
-			MCLGET(m,M_WAIT);
+			MCLGET(m,M_TRYWAIT);
 			mlen = ( (m->m_flags & M_EXT) == 0) ? MLEN : MCLBYTES;
 		} else { 
 			mlen = MLEN;
@@ -135,7 +135,7 @@
 		panic("ncp_mchecksize\n");
 	if (M_TRAILINGSPACE(rqp->mrq)<(size)) {
 		struct mbuf *m;
-		m = m_get(M_WAIT, MT_DATA);
+		m = m_get(M_TRYWAIT, MT_DATA);
 		m->m_len = 0;
 		rqp->bpos = mtod(m, caddr_t);
 		rqp->mrq->m_next = m;
@@ -435,7 +435,7 @@
 	register struct mbuf *m=rqp->mrp, *rm;
 	register unsigned count;
 	
-	rm = m_copym(m, rqp->bpos - mtod(m,caddr_t), size, M_WAIT);
+	rm = m_copym(m, rqp->bpos - mtod(m,caddr_t), size, M_TRYWAIT);
 	while (size > 0) {
 		if (m == 0) {
 			printf("ncp_rp_mbuf: can't advance\n");
@@ -555,9 +555,9 @@
 		while (left > 0) {
 			mlen = M_TRAILINGSPACE(mp);
 			if (mlen == 0) {
-				MGET(mp, M_WAIT, MT_DATA);
+				MGET(mp, M_TRYWAIT, MT_DATA);
 				if (clflg)
-					MCLGET(mp, M_WAIT);
+					MCLGET(mp, M_TRYWAIT);
 				mp->m_len = 0;
 				mp2->m_next = mp;
 				mp2 = mp;
diff -ruN /cvs/sys_old/netncp/ncp_sock.c /usr/src/sys/netncp/ncp_sock.c
--- /cvs/sys_old/netncp/ncp_sock.c	Mon Dec 18 02:40:24 2000
+++ /usr/src/sys/netncp/ncp_sock.c	Mon Dec 18 22:50:24 2000
@@ -171,7 +171,7 @@
 	int sendwait;
 
 	for(;;) {
-		m = m_copym(top, 0, M_COPYALL, M_WAIT);
+		m = m_copym(top, 0, M_COPYALL, M_TRYWAIT);
 /*		NCPDDEBUG(m);*/
 		error = so->so_proto->pr_usrreqs->pru_sosend(so, to, 0, m, 0, flags, p);
 		if (error == 0 || error == EINTR || error == ENETDOWN)
diff -ruN /cvs/sys_old/netns/spp_usrreq.c /usr/src/sys/netns/spp_usrreq.c
--- /cvs/sys_old/netns/spp_usrreq.c	Mon Dec 18 02:40:25 2000
+++ /usr/src/sys/netns/spp_usrreq.c	Mon Dec 18 22:50:54 2000
@@ -743,7 +743,7 @@
 					 * from usrreq(), so it is OK to
 					 * block.
 					 */
-					m = m_copym(m0, 0, mtu, M_WAIT);
+					m = m_copym(m0, 0, mtu, M_TRYWAIT);
 					if (cb->s_flags & SF_NEWCALL) {
 					    struct mbuf *mm = m;
 					    spp_newchecks[7]++;
diff -ruN /cvs/sys_old/nfs/bootp_subr.c /usr/src/sys/nfs/bootp_subr.c
--- /cvs/sys_old/nfs/bootp_subr.c	Mon Dec 18 02:40:25 2000
+++ /usr/src/sys/nfs/bootp_subr.c	Mon Dec 18 22:50:56 2000
@@ -1755,7 +1755,7 @@
 		u_int32_t v3[21];
 	} fattribs;
 	
-	m = m_get(M_WAIT,MT_DATA);
+	m = m_get(M_TRYWAIT,MT_DATA);
 	if (m == NULL)
 	  	return ENOBUFS;
 	
diff -ruN /cvs/sys_old/nfs/krpc_subr.c /usr/src/sys/nfs/krpc_subr.c
--- /cvs/sys_old/nfs/krpc_subr.c	Mon Dec 18 02:40:25 2000
+++ /usr/src/sys/nfs/krpc_subr.c	Mon Dec 18 22:50:59 2000
@@ -149,7 +149,7 @@
 		return 0;
 	}
 
-	m = m_get(M_WAIT, MT_DATA);
+	m = m_get(M_TRYWAIT, MT_DATA);
 	if (m == NULL)
 		return ENOBUFS;
 	sdata = mtod(m, struct sdata *);
@@ -275,7 +275,7 @@
 	/*
 	 * Prepend RPC message header.
 	 */
-	mhead = m_gethdr(M_WAIT, MT_DATA);
+	mhead = m_gethdr(M_TRYWAIT, MT_DATA);
 	mhead->m_next = *data;
 	call = mtod(mhead, struct rpc_call *);
 	mhead->m_len = sizeof(*call);
@@ -315,7 +315,7 @@
 	timo = 0;
 	for (;;) {
 		/* Send RPC request (or re-send). */
-		m = m_copym(mhead, 0, M_COPYALL, M_WAIT);
+		m = m_copym(mhead, 0, M_COPYALL, M_TRYWAIT);
 		if (m == NULL) {
 			error = ENOBUFS;
 			goto out;
@@ -471,9 +471,9 @@
 	if (mlen > MCLBYTES)		/* If too big, we just can't do it. */
 		return (NULL);
 
-	m = m_get(M_WAIT, MT_DATA);
+	m = m_get(M_TRYWAIT, MT_DATA);
 	if (mlen > MLEN) {
-		MCLGET(m, M_WAIT);
+		MCLGET(m, M_TRYWAIT);
 		if ((m->m_flags & M_EXT) == 0) {
 			(void) m_free(m);	/* There can be only one. */
 			return (NULL);
diff -ruN /cvs/sys_old/nfs/nfs_nqlease.c /usr/src/sys/nfs/nfs_nqlease.c
--- /cvs/sys_old/nfs/nfs_nqlease.c	Mon Dec 18 02:40:25 2000
+++ /usr/src/sys/nfs/nfs_nqlease.c	Mon Dec 18 22:51:04 2000
@@ -554,7 +554,7 @@
 			 * Record Mark.
 			 */
 			if (sotype == SOCK_STREAM) {
-				M_PREPEND(m, NFSX_UNSIGNED, M_WAIT);
+				M_PREPEND(m, NFSX_UNSIGNED, M_TRYWAIT);
 				*mtod(m, u_int32_t *) = htonl(0x80000000 |
 					(m->m_pkthdr.len - NFSX_UNSIGNED));
 			}
@@ -932,7 +932,7 @@
 		RPCAUTH_UNIX, 5 * NFSX_UNSIGNED, (char *)0,
 		0, (char *)NULL, mreq, i, &mheadend, &xid);
 	if (nmp->nm_sotype == SOCK_STREAM) {
-		M_PREPEND(m, NFSX_UNSIGNED, M_WAIT);
+		M_PREPEND(m, NFSX_UNSIGNED, M_TRYWAIT);
 		*mtod(m, u_int32_t *) = htonl(0x80000000 | (m->m_pkthdr.len -
 			NFSX_UNSIGNED));
 	}
diff -ruN /cvs/sys_old/nfs/nfs_serv.c /usr/src/sys/nfs/nfs_serv.c
--- /cvs/sys_old/nfs/nfs_serv.c	Mon Dec 18 02:40:25 2000
+++ /usr/src/sys/nfs/nfs_serv.c	Mon Dec 18 22:51:05 2000
@@ -689,8 +689,8 @@
 	len = 0;
 	i = 0;
 	while (len < NFS_MAXPATHLEN) {
-		MGET(mp, M_WAIT, MT_DATA);
-		MCLGET(mp, M_WAIT);
+		MGET(mp, M_TRYWAIT, MT_DATA);
+		MCLGET(mp, M_TRYWAIT);
 		mp->m_len = NFSMSIZ(mp);
 		if (len == 0)
 			mp3 = mp2 = mp;
@@ -940,8 +940,8 @@
 				i++;
 			}
 			if (left > 0) {
-				MGET(m, M_WAIT, MT_DATA);
-				MCLGET(m, M_WAIT);
+				MGET(m, M_TRYWAIT, MT_DATA);
+				MCLGET(m, M_TRYWAIT);
 				m->m_len = 0;
 				m2->m_next = m;
 				m2 = m;
diff -ruN /cvs/sys_old/nfs/nfs_socket.c /usr/src/sys/nfs/nfs_socket.c
--- /cvs/sys_old/nfs/nfs_socket.c	Mon Dec 18 02:40:25 2000
+++ /usr/src/sys/nfs/nfs_socket.c	Mon Dec 18 22:51:06 2000
@@ -590,7 +590,7 @@
 			goto tryagain;
 		}
 		while (rep->r_flags & R_MUSTRESEND) {
-			m = m_copym(rep->r_mreq, 0, M_COPYALL, M_WAIT);
+			m = m_copym(rep->r_mreq, 0, M_COPYALL, M_TRYWAIT);
 			nfsstats.rpcretries++;
 			error = nfs_send(so, rep->r_nmp->nm_nam, m, rep);
 			if (error) {
@@ -1014,7 +1014,7 @@
 	 * For stream protocols, insert a Sun RPC Record Mark.
 	 */
 	if (nmp->nm_sotype == SOCK_STREAM) {
-		M_PREPEND(m, NFSX_UNSIGNED, M_WAIT);
+		M_PREPEND(m, NFSX_UNSIGNED, M_TRYWAIT);
 		*mtod(m, u_int32_t *) = htonl(0x80000000 |
 			 (m->m_pkthdr.len - NFSX_UNSIGNED));
 	}
@@ -1058,7 +1058,7 @@
 		if (nmp->nm_soflags & PR_CONNREQUIRED)
 			error = nfs_sndlock(rep);
 		if (!error) {
-			m2 = m_copym(m, 0, M_COPYALL, M_WAIT);
+			m2 = m_copym(m, 0, M_COPYALL, M_TRYWAIT);
 			error = nfs_send(nmp->nm_so, nmp->nm_nam, m2, rep);
 			if (nmp->nm_soflags & PR_CONNREQUIRED)
 				nfs_sndunlock(rep);
@@ -1237,7 +1237,7 @@
 	caddr_t bpos;
 	struct mbuf *mb, *mb2;
 
-	MGETHDR(mreq, M_WAIT, MT_DATA);
+	MGETHDR(mreq, M_TRYWAIT, MT_DATA);
 	mb = mreq;
 	/*
 	 * If this is a big reply, use a cluster else
@@ -1245,7 +1245,7 @@
 	 */
 	siz += RPC_REPLYSIZ;
 	if ((max_hdr + siz) >= MINCLSIZE) {
-		MCLGET(mreq, M_WAIT);
+		MCLGET(mreq, M_TRYWAIT);
 	} else
 		mreq->m_data += max_hdr;
 	tl = mtod(mreq, u_int32_t *);
@@ -1686,9 +1686,9 @@
 
 	while ((m = *pm) != NULL) {
 		if ((m->m_len & 0x3) || (mtod(m, intptr_t) & 0x3)) {
-			MGET(n, M_WAIT, MT_DATA);
+			MGET(n, M_TRYWAIT, MT_DATA);
 			if (m->m_len >= MINCLSIZE) {
-				MCLGET(n, M_WAIT);
+				MCLGET(n, M_TRYWAIT);
 			}
 			n->m_len = 0;
 			break;
@@ -1978,7 +1978,7 @@
  * Socket upcall routine for the nfsd sockets.
  * The caddr_t arg is a pointer to the "struct nfssvc_sock".
  * Essentially do as much as possible non-blocking, else punt and it will
- * be called with M_WAIT from an nfsd.
+ * be called with M_TRYWAIT from an nfsd.
  */
 void
 nfsrv_rcv(so, arg, waitflag)
diff -ruN /cvs/sys_old/nfs/nfs_srvcache.c /usr/src/sys/nfs/nfs_srvcache.c
--- /cvs/sys_old/nfs/nfs_srvcache.c	Mon Dec 18 02:40:25 2000
+++ /usr/src/sys/nfs/nfs_srvcache.c	Mon Dec 18 22:51:08 2000
@@ -201,7 +201,7 @@
 			} else if (rp->rc_flag & RC_REPMBUF) {
 				nfsstats.srvcache_nonidemdonehits++;
 				*repp = m_copym(rp->rc_reply, 0, M_COPYALL,
-						M_WAIT);
+						M_TRYWAIT);
 				ret = RC_REPLY;
 			} else {
 				nfsstats.srvcache_idemdonehits++;
@@ -313,7 +313,7 @@
 					rp->rc_flag |= RC_REPSTATUS;
 				} else {
 					rp->rc_reply = m_copym(repmbuf,
-						0, M_COPYALL, M_WAIT);
+						0, M_COPYALL, M_TRYWAIT);
 					rp->rc_flag |= RC_REPMBUF;
 				}
 			}
diff -ruN /cvs/sys_old/nfs/nfs_subs.c /usr/src/sys/nfs/nfs_subs.c
--- /cvs/sys_old/nfs/nfs_subs.c	Mon Dec 18 02:40:25 2000
+++ /usr/src/sys/nfs/nfs_subs.c	Mon Dec 18 22:51:09 2000
@@ -588,9 +588,9 @@
 	struct nfsmount *nmp;
 	int nqflag;
 
-	MGET(mb, M_WAIT, MT_DATA);
+	MGET(mb, M_TRYWAIT, MT_DATA);
 	if (hsiz >= MINCLSIZE)
-		MCLGET(mb, M_WAIT);
+		MCLGET(mb, M_TRYWAIT);
 	mb->m_len = 0;
 	bpos = mtod(mb, caddr_t);
 
@@ -646,9 +646,9 @@
 	int siz, grpsiz, authsiz;
 
 	authsiz = nfsm_rndup(auth_len);
-	MGETHDR(mb, M_WAIT, MT_DATA);
+	MGETHDR(mb, M_TRYWAIT, MT_DATA);
 	if ((authsiz + 10 * NFSX_UNSIGNED) >= MINCLSIZE) {
-		MCLGET(mb, M_WAIT);
+		MCLGET(mb, M_TRYWAIT);
 	} else if ((authsiz + 10 * NFSX_UNSIGNED) < MHLEN) {
 		MH_ALIGN(mb, authsiz + 10 * NFSX_UNSIGNED);
 	} else {
@@ -711,9 +711,9 @@
 		siz = auth_len;
 		while (siz > 0) {
 			if (M_TRAILINGSPACE(mb) == 0) {
-				MGET(mb2, M_WAIT, MT_DATA);
+				MGET(mb2, M_TRYWAIT, MT_DATA);
 				if (siz >= MINCLSIZE)
-					MCLGET(mb2, M_WAIT);
+					MCLGET(mb2, M_TRYWAIT);
 				mb->m_next = mb2;
 				mb = mb2;
 				mb->m_len = 0;
@@ -744,9 +744,9 @@
 		siz = verf_len;
 		while (siz > 0) {
 			if (M_TRAILINGSPACE(mb) == 0) {
-				MGET(mb2, M_WAIT, MT_DATA);
+				MGET(mb2, M_TRYWAIT, MT_DATA);
 				if (siz >= MINCLSIZE)
-					MCLGET(mb2, M_WAIT);
+					MCLGET(mb2, M_TRYWAIT);
 				mb->m_next = mb2;
 				mb = mb2;
 				mb->m_len = 0;
@@ -887,9 +887,9 @@
 		while (left > 0) {
 			mlen = M_TRAILINGSPACE(mp);
 			if (mlen == 0) {
-				MGET(mp, M_WAIT, MT_DATA);
+				MGET(mp, M_TRYWAIT, MT_DATA);
 				if (clflg)
-					MCLGET(mp, M_WAIT);
+					MCLGET(mp, M_TRYWAIT);
 				mp->m_len = 0;
 				mp2->m_next = mp;
 				mp2 = mp;
@@ -919,7 +919,7 @@
 	}
 	if (rem > 0) {
 		if (rem > M_TRAILINGSPACE(mp)) {
-			MGET(mp, M_WAIT, MT_DATA);
+			MGET(mp, M_TRYWAIT, MT_DATA);
 			mp->m_len = 0;
 			mp2->m_next = mp;
 		}
@@ -968,7 +968,7 @@
 	} else if (siz > MHLEN) {
 		panic("nfs S too big");
 	} else {
-		MGET(mp2, M_WAIT, MT_DATA);
+		MGET(mp2, M_TRYWAIT, MT_DATA);
 		mp2->m_next = mp->m_next;
 		mp->m_next = mp2;
 		mp->m_len -= left;
@@ -1061,9 +1061,9 @@
 	}
 	/* Loop around adding mbufs */
 	while (siz > 0) {
-		MGET(m1, M_WAIT, MT_DATA);
+		MGET(m1, M_TRYWAIT, MT_DATA);
 		if (siz > MLEN)
-			MCLGET(m1, M_WAIT);
+			MCLGET(m1, M_TRYWAIT);
 		m1->m_len = NFSMSIZ(m1);
 		m2->m_next = m1;
 		m2 = m1;
diff -ruN /cvs/sys_old/nfs/nfs_syscalls.c /usr/src/sys/nfs/nfs_syscalls.c
--- /cvs/sys_old/nfs/nfs_syscalls.c	Mon Dec 18 02:40:25 2000
+++ /usr/src/sys/nfs/nfs_syscalls.c	Mon Dec 18 22:51:11 2000
@@ -480,7 +480,7 @@
 					slp->ns_flag &= ~SLP_NEEDQ;
 					(void) nfs_slplock(slp, 1);
 					nfsrv_rcv(slp->ns_so, (caddr_t)slp,
-						M_WAIT);
+						M_TRYWAIT);
 					nfs_slpunlock(slp);
 				}
 				error = nfsrv_dorec(slp, nfsd, &nd);
@@ -632,7 +632,7 @@
 			 * Record Mark.
 			 */
 			if (sotype == SOCK_STREAM) {
-				M_PREPEND(m, NFSX_UNSIGNED, M_WAIT);
+				M_PREPEND(m, NFSX_UNSIGNED, M_TRYWAIT);
 				*mtod(m, u_int32_t *) = htonl(0x80000000 | siz);
 			}
 			if (slp->ns_so->so_proto->pr_flags & PR_CONNREQUIRED)
diff -ruN /cvs/sys_old/nfs/nfsm_subs.h /usr/src/sys/nfs/nfsm_subs.h
--- /cvs/sys_old/nfs/nfsm_subs.h	Mon Dec 18 02:40:25 2000
+++ /usr/src/sys/nfs/nfsm_subs.h	Mon Dec 18 22:51:16 2000
@@ -94,7 +94,7 @@
 #define	nfsm_build(a,c,s) \
 	do { \
 		if ((s) > M_TRAILINGSPACE(mb)) { \
-			MGET(mb2, M_WAIT, MT_DATA); \
+			MGET(mb2, M_TRYWAIT, MT_DATA); \
 			if ((s) > MLEN) \
 				panic("build > MLEN"); \
 			mb->m_next = mb2; \
@@ -491,8 +491,8 @@
 		if (bp >= be) { \
 			if (mp == mb) \
 				mp->m_len += bp-bpos; \
-			MGET(mp, M_WAIT, MT_DATA); \
-			MCLGET(mp, M_WAIT); \
+			MGET(mp, M_TRYWAIT, MT_DATA); \
+			MCLGET(mp, M_TRYWAIT); \
 			mp->m_len = NFSMSIZ(mp); \
 			mp2->m_next = mp; \
 			mp2 = mp; \
diff -ruN /cvs/sys_old/pci/if_mn.c /usr/src/sys/pci/if_mn.c
--- /cvs/sys_old/pci/if_mn.c	Mon Dec 18 02:40:31 2000
+++ /usr/src/sys/pci/if_mn.c	Mon Dec 18 22:52:51 2000
@@ -605,7 +605,7 @@
 	/* Setup a transmit chain with one descriptor */
 	/* XXX: we actually send a 1 byte packet */
 	dp = mn_alloc_desc();
-	MGETHDR(m, M_WAIT, MT_DATA);
+	MGETHDR(m, M_TRYWAIT, MT_DATA);
 	if (m == NULL)
 		return ENOBUFS;
 	m->m_pkthdr.len = 0;
@@ -622,12 +622,12 @@
 
 	dp = mn_alloc_desc();
 	m = NULL;
-	MGETHDR(m, M_WAIT, MT_DATA);
+	MGETHDR(m, M_TRYWAIT, MT_DATA);
 	if (m == NULL) {
 		mn_free_desc(dp);
 		return (ENOBUFS);
 	}
-	MCLGET(m, M_WAIT);
+	MCLGET(m, M_TRYWAIT);
 	if ((m->m_flags & M_EXT) == 0) {
 		mn_free_desc(dp);
 		m_freem(m);
@@ -645,13 +645,13 @@
 		dp2 = dp;
 		dp = mn_alloc_desc();
 		m = NULL;
-		MGETHDR(m, M_WAIT, MT_DATA);
+		MGETHDR(m, M_TRYWAIT, MT_DATA);
 		if (m == NULL) {
 			mn_free_desc(dp);
 			m_freem(m);
 			return (ENOBUFS);
 		}
-		MCLGET(m, M_WAIT);
+		MCLGET(m, M_TRYWAIT);
 		if ((m->m_flags & M_EXT) == 0) {
 			mn_free_desc(dp);
 			m_freem(m);
diff -ruN /cvs/sys_old/sys/mbuf.h /usr/src/sys/sys/mbuf.h
--- /cvs/sys_old/sys/mbuf.h	Mon Dec 18 02:40:33 2000
+++ /usr/src/sys/sys/mbuf.h	Mon Dec 18 23:10:00 2000
@@ -227,7 +227,8 @@
 
 /* flags to m_get/MGET */
 #define	M_DONTWAIT	1
-#define	M_WAIT		0
+#define	M_TRYWAIT	0
+#define	M_WAIT		M_TRYWAIT	/* XXX: Deprecated. */
 
 /*
  * Normal mbuf clusters are normally treated as character arrays
@@ -362,7 +363,7 @@
 		mmbfree.m_head = (m_mget)->m_next;			\
 		mbtypes[MT_FREE]--;					\
 	} else {							\
-		if ((m_get_how) == M_WAIT)				\
+		if ((m_get_how) == M_TRYWAIT)				\
 			(m_mget) = m_mballoc_wait();			\
 	}								\
 } while (0)
@@ -429,7 +430,7 @@
 		mbstat.m_clfree--;					\
 		mclfree.m_head = ((union mcluster *)_mp)->mcl_next;	\
 	} else {							\
-		if (_mhow == M_WAIT)					\
+		if (_mhow == M_TRYWAIT)					\
 			_mp = m_clalloc_wait();				\
 	}								\
 	(p) = _mp;							\
@@ -460,7 +461,7 @@
 #define MEXTADD(m, buf, size, free, args, flags, type) do {		\
 	struct mbuf *_mm = (m);						\
 									\
-	MEXT_INIT_REF(_mm, M_WAIT);					\
+	MEXT_INIT_REF(_mm, M_TRYWAIT);					\
 	if (_mm->m_ext.ref_cnt != NULL) {				\
 		_mm->m_flags |= (M_EXT | (flags));			\
 		_mm->m_ext.ext_buf = (caddr_t)(buf);			\
@@ -588,8 +589,8 @@
 /*
  * Arrange to prepend space of size plen to mbuf m.
  * If a new mbuf must be allocated, how specifies whether to wait.
- * If how is M_DONTWAIT and allocation fails, the original mbuf chain
- * is freed and m is set to NULL.
+ * If the allocation fails, the original mbuf chain is freed and m is
+ * set to NULL.
  */
 #define	M_PREPEND(m, plen, how) do {					\
 	struct mbuf **_mmp = &(m);					\