o add a flags parameter to netisr_register that is used to specify

  whether or not the isr needs to hold Giant when running; Giant-less
  operation is also controlled by the setting of debug_mpsafenet
o mark all netisr's except NETISR_IP as needing Giant
o add a GIANT_REQUIRED assertion to the top of netisr's that need Giant
o pickup Giant (when debug_mpsafenet is 1) inside ip_input before
  calling up with a packet
o change netisr handling so swi_net runs w/o Giant; instead we grab
  Giant before invoking handlers based on whether the handler needs Giant
o change netisr handling so that netisr's that are marked MPSAFE may
  have multiple instances active at a time
o add netisr statistics for packets dropped because the isr is inactive

Supported by:	FreeBSD Foundation

1 files changed, 3 insertions, 1 deletions

diff --git a/sys/netinet/ip_input.c b/sys/netinet/ip_input.c
index 26cc060..2f2dc96 100644
--- a/sys/netinet/ip_input.c
+++ b/sys/netinet/ip_input.c
@@ -334,7 +334,7 @@ ip_init()
 #endif
 	ipintrq.ifq_maxlen = ipqmaxlen;
 	mtx_init(&ipintrq.ifq_mtx, "ip_inq", NULL, MTX_DEF);
-	netisr_register(NETISR_IP, ip_input, &ipintrq);
+	netisr_register(NETISR_IP, ip_input, &ipintrq, NETISR_MPSAFE);
 }
 
 /*
@@ -1009,6 +1009,7 @@ DPRINTF(("ip_input: no SP, packet discarded\n"));/*XXX*/
 	 * Switch out to protocol's input routine.
 	 */
 	ipstat.ips_delivered++;
+	NET_PICKUP_GIANT();
 	if (args.next_hop && ip->ip_p == IPPROTO_TCP) {
 		/* TCP needs IPFORWARD info if available */
 		struct m_hdr tag;
@@ -1022,6 +1023,7 @@ DPRINTF(("ip_input: no SP, packet discarded\n"));/*XXX*/
 			(struct mbuf *)&tag, hlen);
 	} else
 		(*inetsw[ip_protox[ip->ip_p]].pr_input)(m, hlen);
+	NET_DROP_GIANT();
 	return;
 bad:
 	m_freem(m);