From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sasha Khapyorsky Subject: Re: [PATCH 2/3 v2] opensm: connect switches in tree - implemented in fat-tree Date: Thu, 26 Nov 2009 17:49:48 +0200 Message-ID: <20091126154948.GB13817@me> References: <4AF160D1.1010804@dev.mellanox.co.il> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <4AF160D1.1010804-LDSdmyG8hGV8YrgS2mwiifqBs+8SCbDb@public.gmane.org> Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Yevgeny Kliteynik Cc: Linux RDMA List-Id: linux-rdma@vger.kernel.org On 13:09 Wed 04 Nov , Yevgeny Kliteynik wrote: > This patch implements connect_roots and connect_switches > option in fat-tree. Actually, both options mapped to the > same implementation. > > The idea is the following: pick some leaf switch in the > fabric. Now go over all the switches above the leaf level > in the tree. If these switches don't know how to route to > some LID and the selected leaf switch does know, route this > LID to the leaf switch. > > [v2 - no changes, just rebased] > > Signed-off-by: Yevgeny Kliteynik > --- > opensm/opensm/osm_ucast_ftree.c | 92 +++++++++++++++++++++++++++++++++++++++ > 1 files changed, 92 insertions(+), 0 deletions(-) > > diff --git a/opensm/opensm/osm_ucast_ftree.c b/opensm/opensm/osm_ucast_ftree.c > index 1b1da19..ddb77b7 100644 > --- a/opensm/opensm/osm_ucast_ftree.c > +++ b/opensm/opensm/osm_ucast_ftree.c > @@ -2949,6 +2949,90 @@ static void fabric_route_to_switches(IN ftree_fabric_t * p_ftree) > /*************************************************** > ***************************************************/ > > +static void fabric_route_down_up_switches(IN ftree_fabric_t * p_ftree) > +{ > + uint16_t lid; > + uint8_t port_num; > + osm_port_t *p_port; > + ftree_sw_t *p_sw; > + ftree_sw_t *p_leaf_sw; > + > + OSM_LOG_ENTER(&p_ftree->p_osm->log); > + > + /* > + * We need a switch that will accomodate all the down/up turns in > + * the fabric. Having these turn in a single place in the fabric > + * will not create credit loops. > + * So we need to select this switch. > + * The idea here is to chose leaf with the highest index. I don't > + * have any theory to back me up on this. It's just a general thought > + * that this way the switch that might be a bottleneck for many mcast > + * groups will be far away from the OpenSM, so it will draw the > + * multicast traffic away from the SM. > + */ > + > + p_leaf_sw = p_ftree->leaf_switches[p_ftree->leaf_switches_num-1]; > + > + /* > + * Now go over all the switches in the fabric that > + * have lower rank, and route the missing LIDs to > + * the selected leaf switch. > + * In short, this leaf switch now poses a target > + * for all those missing LIDs. > + */ > + > + for (p_sw = (ftree_sw_t *) cl_qmap_head(&p_ftree->sw_tbl); > + p_sw != (ftree_sw_t *) cl_qmap_end(&p_ftree->sw_tbl); > + p_sw = (ftree_sw_t *) cl_qmap_next(&p_sw->map_item)) { > + > + if (p_sw->rank >= p_ftree->leaf_switch_rank) > + continue; > + > + for (lid = 1; lid <= p_leaf_sw->p_osm_sw->max_lid_ho; lid ++) { > + > + if (p_sw->p_osm_sw->new_lft[lid] != OSM_NO_PATH || > + p_leaf_sw->hops[lid] == OSM_NO_PATH) > + continue; > + > + p_port = cl_ptr_vector_get( > + &p_ftree->p_osm->subn.port_lid_tbl, lid); > + > + /* we're interested only in switches */ > + if (!p_port && !p_port->p_node && !p_port->p_node->sw) 'p_port->p_node = NULL' is invalid case and this check is not needed. > + continue; > + > + /* > + * the missing LID will be routed through the same > + * port that routes to the selected leaf switch > + */ > + port_num = p_sw->p_osm_sw->new_lft[p_leaf_sw->base_lid]; > + > + OSM_LOG(&p_ftree->p_osm->log, OSM_LOG_DEBUG, > + "Switch %s: setting path to LID %u " > + "through port %u\n", > + tuple_to_str(p_sw->tuple), lid, port_num); > + > + /* set local lft */ > + p_sw->p_osm_sw->new_lft[lid] = port_num; > + > + /* > + * Set local min hop table. > + * The distance to the target LID is a distance > + * to the selected leaf switch plus the distance > + * from the leaf to the target LID. > + */ > + sw_set_hops(p_sw, lid, port_num, > + p_sw->hops[p_leaf_sw->base_lid] + > + p_leaf_sw->hops[lid], TRUE); > + } > + } > + > + OSM_LOG_EXIT(&p_ftree->p_osm->log); > +} /* fabric_route_roots() */ > + > +/*************************************************** > + ***************************************************/ Such comments were removed recently, please don't introduce a new ones. Sasha > + > static int fabric_populate_nodes(IN ftree_fabric_t * p_ftree) > { > osm_node_t *p_osm_node; > @@ -3978,6 +4062,14 @@ static int do_routing(IN void *context) > "Filling switch forwarding tables for switch-to-switch paths\n"); > fabric_route_to_switches(p_ftree); > > + if (p_ftree->p_osm->subn.opt.connect_roots || > + p_ftree->p_osm->subn.opt.connect_switches) { > + OSM_LOG(&p_ftree->p_osm->log, OSM_LOG_VERBOSE, > + "Connecting switches that are unreachable within " > + "Up/Down rules\n"); > + fabric_route_down_up_switches(p_ftree); > + } > + > /* for each switch, set its fwd table */ > cl_qmap_apply_func(&p_ftree->sw_tbl, set_sw_fwd_table, (void *)p_ftree); > > -- > 1.5.1.4 > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-rdma" in > the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html