rsocket: Handle TCP_MAXSEG socket option

netperf uses the TCP_MAXSEG socket option.  Add support for it.
Problem reported by Sridhar Samudrala <sri@us.ibm.com>

Signed-off-by: Sean Hefty <sean.hefty@intel.com>

diff --git a/src/rsocket.c b/src/rsocket.c
index 8f20b4abdcaf0a1421ec85e5e5a943331d317061..2fd106a4ea2b1a19ade67e089d4f3d706c150bfb 100644 (file)
--- a/src/rsocket.c
+++ b/src/rsocket.c
@@ -1716,6 +1716,9 @@ int rsetsockopt(int socket, int level, int optname,
                        opt_on = *(int *) optval;
                        ret = 0;
                        break;
+               case TCP_MAXSEG:
+                       ret = 0;
+                       break;
                default:
                        break;
                }
@@ -1802,6 +1805,12 @@ int rgetsockopt(int socket, int level, int optname,
                        *((int *) optval) = !!(rs->tcp_opts & (1 << optname));
                        *optlen = sizeof(int);
                        break;
+               case TCP_MAXSEG:
+                       *((int *) optval) = (rs->cm_id && rs->cm_id->route.num_paths) ?
+                                           1 << (7 + rs->cm_id->route.path_rec->mtu) :
+                                           2048;
+                       *optlen = sizeof(int);
+                       break;
                default:
                        ret = ENOTSUP;
                        break;