On 18/06/2018 12:52, Eelco Chaudron wrote: > > > On 11 Jun 2018, at 18:21, Tiago Lam wrote: > >> The dp_packet_put_uninit() function is, in its current implementation, >> operating on the data buffer of a dp_packet as if it were contiguous, >> which in the case of multi-segment mbufs means they operate on the >> first >> mbuf in the chain. However, when making use of multi-segment mbufs, it >> is the data length of the last mbuf in the mbuf chain that should be >> adjusted. This function has thus been modified to support >> multi-segment >> mbufs. >> >> Co-authored-by: Mark Kavanagh <mark.b.kavan...@intel.com> >> >> Signed-off-by: Mark Kavanagh <mark.b.kavan...@intel.com> >> Signed-off-by: Tiago Lam <tiago....@intel.com> >> --- >> lib/dp-packet.c | 12 ++++++++++++ >> 1 file changed, 12 insertions(+) >> >> diff --git a/lib/dp-packet.c b/lib/dp-packet.c >> index 2aaeaae..9f8503e 100644 >> --- a/lib/dp-packet.c >> +++ b/lib/dp-packet.c >> @@ -321,7 +321,19 @@ dp_packet_put_uninit(struct dp_packet *b, size_t >> size) >> void *p; >> dp_packet_prealloc_tailroom(b, size); >> p = dp_packet_tail(b); >> +#ifdef DPDK_NETDEV >> + struct rte_mbuf *mbuf; >> + >> + if (b->source == DPBUF_DPDK) { >> + mbuf = rte_pktmbuf_lastseg(&b->mbuf); >> + } else { >> + mbuf = CONST_CAST(struct rte_mbuf *, &b->mbuf); >> + } >> + >> + mbuf->data_len += size; > > How can we be sure there is room in the (last) mbuf->data? The > dp_packet_set_size() is not allocating more room (but it's truncating).
dp_packet_prealloc_tailroom() called at the top is responsible for arranging memory and make sure it returns with enough memory. Otherwise, it keeps the same behavior of hard asserting. > The mbuf->data_len should be handled in dp_packet_set_size(), and not > here so it will work for all these cases. > This was a leftover, thanks for spotting it! I've fixed it and will include with the next iteration. Tiago. _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev