bgpd: efficient NLRI packing for AFs != ipv4-unicast
ISSUE:
Currently, for non-ipv4-unicast address families where prefixes are
encoded in MP_REACH/MP_UNREACH attributes, BGP ends up sending one
prefix per UPDATE message. This is quite inefficient. The patch
addresses the issue.
PATCH:
We introduce a scratch buffer in the peer structure that stores the
MP_REACH/MP_UNREACH attributes for non-ipv4-unicast families. This
enables us to encode multiple prefixes. In the end, the two buffers
are merged to create the UPDATE packet.
Signed-off-by: Pradosh Mohapatra <pmohapat@cumulusnetworks.com>
Reviewed-by: Daniel Walton <dwalton@cumulusnetworks.com>
[DL: removed no longer existing bgp_packet_withdraw prototype]
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>
diff --git a/lib/stream.c b/lib/stream.c
index ccd4623..9a6fcbc 100644
--- a/lib/stream.c
+++ b/lib/stream.c
@@ -154,6 +154,25 @@
return (stream_copy (new, s));
}
+struct stream *
+stream_dupcat (struct stream *s1, struct stream *s2, size_t offset)
+{
+ struct stream *new;
+
+ STREAM_VERIFY_SANE (s1);
+ STREAM_VERIFY_SANE (s2);
+
+ if ( (new = stream_new (s1->endp + s2->endp)) == NULL)
+ return NULL;
+
+ memcpy (new->data, s1->data, offset);
+ memcpy (new->data + offset, s2->data, s2->endp);
+ memcpy (new->data + offset + s2->endp, s1->data + offset,
+ (s1->endp - offset));
+ new->endp = s1->endp + s2->endp;
+ return new;
+}
+
size_t
stream_resize (struct stream *s, size_t newsize)
{