Add support for receiving and setting flowtype, flowid and RSS bucket

information as part of recvmsg().

This is primarily used for debugging/verification of the various
processing paths in the IP, PCB and driver layers.

Unfortunately the current implementation of the control message path
results in a ~10% or so drop in UDP frame throughput when it's used.

Differential Revision:	https://reviews.freebsd.org/D527
Reviewed by:	grehan

1 files changed, 37 insertions, 0 deletions

diff --git a/sys/netinet/ip_input.c b/sys/netinet/ip_input.c
index d622e01..c16017d 100644
--- a/sys/netinet/ip_input.c
+++ b/sys/netinet/ip_input.c
@@ -1662,6 +1662,43 @@ makedummy:
 		if (*mp)
 			mp = &(*mp)->m_next;
 	}
+
+	if (inp->inp_flags2 & INP_RECVFLOWID) {
+		uint32_t flowid, flow_type;
+
+		flowid = m->m_pkthdr.flowid;
+		flow_type = M_HASHTYPE_GET(m);
+
+		/*
+		 * XXX should handle the failure of one or the
+		 * other - don't populate both?
+		 */
+		*mp = sbcreatecontrol((caddr_t) &flowid,
+		    sizeof(uint32_t), IP_FLOWID, IPPROTO_IP);
+		if (*mp)
+			mp = &(*mp)->m_next;
+		*mp = sbcreatecontrol((caddr_t) &flow_type,
+		    sizeof(uint32_t), IP_FLOWTYPE, IPPROTO_IP);
+		if (*mp)
+			mp = &(*mp)->m_next;
+	}
+
+#ifdef	RSS
+	if (inp->inp_flags2 & INP_RECVRSSBUCKETID) {
+		uint32_t flowid, flow_type;
+		uint32_t rss_bucketid;
+
+		flowid = m->m_pkthdr.flowid;
+		flow_type = M_HASHTYPE_GET(m);
+
+		if (rss_hash2bucket(flowid, flow_type, &rss_bucketid) == 0) {
+			*mp = sbcreatecontrol((caddr_t) &rss_bucketid,
+			   sizeof(uint32_t), IP_RSSBUCKETID, IPPROTO_IP);
+			if (*mp)
+				mp = &(*mp)->m_next;
+		}
+	}
+#endif
 }
 
 /*