From 48242f4767c5268dbf0a23b3be42fafb34d7e25f Mon Sep 17 00:00:00 2001
From: Sepherosa Ziehau <sephe@dragonflybsd.org>
Date: Sun, 24 Jul 2011 15:24:34 +0800
Subject: [PATCH] ethernet: Add ether_demux(), which will send the packet to
 the correct netisr

It is intended to be used by the function which does not know whether
the current thread is the correct netisr for the ethernet packet or not.

Currently only ng_ether uses this function, which incorrectly called
ether_demux_oncpu().  The other two callers of ether_demux_oncpu() are
already on the correct netisr.

This paves the way to avoid requeuing the packet to the current netisr
in the ether_demux_oncpu().
---
 sys/net/if_ethersubr.c        | 34 ++++++++++++++++++++++++++++++++++
 sys/net/if_var.h              |  1 +
 sys/netgraph/ether/ng_ether.c |  7 +------
 3 files changed, 36 insertions(+), 6 deletions(-)

diff --git a/sys/net/if_ethersubr.c b/sys/net/if_ethersubr.c
index c666ab4774..e6300c7a33 100644
--- a/sys/net/if_ethersubr.c
+++ b/sys/net/if_ethersubr.c
@@ -1709,4 +1709,38 @@ ether_characterize(struct mbuf **m0)
 	return isr;
 }
 
+static void
+ether_demux_handler(netmsg_t nmsg)
+{
+	struct netmsg_packet *nmp = &nmsg->packet;	/* actual size */
+	struct ifnet *ifp;
+	struct mbuf *m;
+
+	m = nmp->nm_packet;
+	M_ASSERTPKTHDR(m);
+	ifp = m->m_pkthdr.rcvif;
+
+	ether_demux_oncpu(ifp, m);
+}
+
+void
+ether_demux(struct mbuf *m)
+{
+	struct netmsg_packet *pmsg;
+	int isr;
+
+	isr = ether_characterize(&m);
+	if (m == NULL)
+		return;
+
+	KKASSERT(m->m_flags & M_HASH);
+	pmsg = &m->m_hdr.mh_netmsg;
+	netmsg_init(&pmsg->base, NULL, &netisr_apanic_rport,
+	    0, ether_demux_handler);
+	pmsg->nm_packet = m;
+	pmsg->base.lmsg.u.ms_result = isr;
+
+	lwkt_sendmsg(cpu_portfn(m->m_pkthdr.hash), &pmsg->base.lmsg);
+}
+
 MODULE_VERSION(ether, 1);
diff --git a/sys/net/if_var.h b/sys/net/if_var.h
index 114eb5f9dd..e5a6efbe3f 100644
--- a/sys/net/if_var.h
+++ b/sys/net/if_var.h
@@ -740,6 +740,7 @@ void	ether_ifattach(struct ifnet *, uint8_t *, struct lwkt_serialize *);
 void	ether_ifattach_bpf(struct ifnet *, uint8_t *, u_int, u_int,
 			struct lwkt_serialize *);
 void	ether_ifdetach(struct ifnet *);
+void	ether_demux(struct mbuf *);
 void	ether_demux_oncpu(struct ifnet *, struct mbuf *);
 void	ether_reinput_oncpu(struct ifnet *, struct mbuf *, int);
 void	ether_input_chain(struct ifnet *, struct mbuf *,
diff --git a/sys/netgraph/ether/ng_ether.c b/sys/netgraph/ether/ng_ether.c
index 682c63b3ab..e00a5b866c 100644
--- a/sys/netgraph/ether/ng_ether.c
+++ b/sys/netgraph/ether/ng_ether.c
@@ -630,13 +630,8 @@ ng_ether_rcv_upper(node_p node, struct mbuf *m, meta_p meta)
 
 	m->m_pkthdr.rcvif = priv->ifp;
 
-	/*
-	 * XXX
-	 * Since frame processing is run in netisr0,
-	 * 'm' may _not_ even on its target CPU.
-	 */
 	/* Route packet back in */
-	ether_demux_oncpu(priv->ifp, m);
+	ether_demux(m);
 	return (0);
 }
 
-- 
2.11.4.GIT