svn commit: r278103 - head/sys/netinet

[Hans Petter Selasky]

Author: hselasky
Date: Mon Feb  2 17:32:50 2015
New Revision: 278103
URL: https://svnweb.freebsd.org/changeset/base/278103

Log:
  The flowid and hashtype should be copied from the originating packet
  when fragmenting IP packets to preserve the order of the packets in a
  stream. Else the resulting fragments can be sent out of order when the
  hardware supports multiple transmit rings.
  
  Reviewed by:	glebius @
  MFC after:	1 week
  Sponsored by:	Mellanox Technologies

Modified:
  head/sys/netinet/ip_output.c

Modified: head/sys/netinet/ip_output.c
==============================================================================
--- head/sys/netinet/ip_output.c	Mon Feb  2 16:19:11 2015	(r278102)
+++ head/sys/netinet/ip_output.c	Mon Feb  2 17:32:50 2015	(r278103)
@@ -789,6 +789,10 @@ smart_frag_failure:
 			IPSTAT_INC(ips_odropped);
 			goto done;
 		}
+		/* make sure the flowid is the same for the fragmented mbufs */
+		M_HASHTYPE_SET(m, M_HASHTYPE_GET(m0));
+		m->m_pkthdr.flowid = m0->m_pkthdr.flowid;
+		/* copy multicast flag, if any */
 		m->m_flags |= (m0->m_flags & M_MCAST);
 		/*
 		 * In the first mbuf, leave room for the link header, then