Re: [PATCH 3/3 v2] opensm: connect switches in tree - implemented in up/down

[Sasha Khapyorsky <sashak-smomgflXvOZWk0Htik3J/w@public.gmane.org>]

On 13:09 Wed 04 Nov     , Yevgeny Kliteynik wrote:
> This patch implements connect_switches option in up/down
> routing. Also, connect_roots is now handled as a special
> case of connect_switches.
> 
> The idea is the following: when clearing hops, preserve
> the entries for switches that are above the highest leaf
> in the tree.
> So if the highest leaf in the tree has rank N, preserve
> hops to all the switches with ranks 0 to (N-1).
> When connecting roots (--connect_roots option), just set
> N to 1.

Would this affect multicast routing in sense of a credit loop
generation?

Sasha

> 
> [v2 - no changes, just rebased and resolved conflicts]
> 
> Signed-off-by: Yevgeny Kliteynik <kliteyn-LDSdmyG8hGV8YrgS2mwiifqBs+8SCbDb@public.gmane.org>
> ---
>  opensm/opensm/osm_ucast_updn.c |   87 +++++++++++++++++++++++++++++++---------
>  1 files changed, 68 insertions(+), 19 deletions(-)
> 
> diff --git a/opensm/opensm/osm_ucast_updn.c b/opensm/opensm/osm_ucast_updn.c
> index 01e40eb..cb99730 100644
> --- a/opensm/opensm/osm_ucast_updn.c
> +++ b/opensm/opensm/osm_ucast_updn.c
> @@ -279,24 +279,80 @@ static int updn_subn_rank(IN updn_t * p_updn)
>  	return 0;
>  }
> 
> -/* hack: preserve min hops entries to any other root switches */
> -static void updn_clear_non_root_hops(updn_t * p_updn, osm_switch_t * p_sw)
> +/**********************************************************************
> + **********************************************************************/
> +/* Preserve min hops entries to any switch
> + * above certain level in the tree */
> +static void updn_switch_clear_hops_below_rank(updn_t * p_updn,
> +	osm_switch_t * p_sw, unsigned min_leaf_rank)
>  {
>  	osm_port_t *p_port;
>  	unsigned i;
> 
>  	for (i = 0; i < p_sw->num_hops; i++)
>  		if (p_sw->hops[i]) {
> -			p_port =
> -			    cl_ptr_vector_get(&p_updn->p_osm->subn.port_lid_tbl,
> -					      i);
> -			if (!p_port || !p_port->p_node->sw
> -			    || ((struct updn_node *)p_port->p_node->sw->priv)->
> -			    rank != 0)
> +			p_port = cl_ptr_vector_get(
> +				&p_updn->p_osm->subn.port_lid_tbl, i);
> +			if (!p_port || !p_port->p_node->sw ||
> +			    ((struct updn_node *)
> +			    p_port->p_node->sw->priv)->rank >= min_leaf_rank)
>  				memset(p_sw->hops[i], 0xff, p_sw->num_ports);
>  		}
>  }
> 
> +/**********************************************************************
> + **********************************************************************/
> +static void updn_clear_hops(IN updn_t * p_updn)
> +{
> +	osm_subn_t *p_subn = &p_updn->p_osm->subn;
> +	osm_switch_t *p_sw;
> +	struct updn_node * p_updn_sw;
> +	osm_physp_t * p_physp;
> +	osm_port_t * p_port;
> +	cl_map_item_t *item;
> +	unsigned min_leaf_rank = 0xff;
> +
> +	if (p_subn->opt.connect_switches) {
> +		/*
> +		 * Preserve roots to switches above the highest leaf
> +		 * switch (leaf switch with the lowest rank).
> +		 *
> +		 * Need to find the minimal rank of leaf switch.
> +		 * The fastest way would be to go through all the
> +		 * CA ports in the fabric and check the switch that
> +		 * is connected to them.
> +		 */
> +		for (item = cl_qmap_head(&p_updn->p_osm->subn.port_guid_tbl);
> +		     item != cl_qmap_end(&p_updn->p_osm->subn.port_guid_tbl);
> +		     item = cl_qmap_next(item)) {
> +			p_port = (osm_port_t *)item;
> +			if (p_port->p_node->sw)
> +				continue;
> +			p_physp = p_port->p_physp->p_remote_physp;
> +			if (!p_physp || !p_physp->p_node->sw)
> +				continue;
> +
> +			p_updn_sw = (struct updn_node*)p_physp->p_node->sw->priv;
> +			if (p_updn_sw->rank < min_leaf_rank)
> +				min_leaf_rank = p_updn_sw->rank;
> +		}
> +	} else if (p_subn->opt.connect_roots)
> +		min_leaf_rank = 1;
> +
> +	for (item = cl_qmap_head(&p_updn->p_osm->subn.sw_guid_tbl);
> +	     item != cl_qmap_end(&p_updn->p_osm->subn.sw_guid_tbl);
> +	     item = cl_qmap_next(item)) {
> +		p_sw = (osm_switch_t *)item;
> +		if (p_subn->opt.connect_switches || p_subn->opt.connect_roots)
> +			updn_switch_clear_hops_below_rank(
> +				p_updn, p_sw, min_leaf_rank);
> +		else
> +			osm_switch_clear_hops(p_sw);
> +	}
> +}
> +
> +/**********************************************************************
> + **********************************************************************/
>  static int updn_set_min_hop_table(IN updn_t * p_updn)
>  {
>  	osm_subn_t *p_subn = &p_updn->p_osm->subn;
> @@ -311,16 +367,8 @@ static int updn_set_min_hop_table(IN updn_t * p_updn)
>  	OSM_LOG(p_log, OSM_LOG_VERBOSE,
>  		"Init Min Hop Table of all switches [\n");
> 
> -	for (item = cl_qmap_head(&p_updn->p_osm->subn.sw_guid_tbl);
> -	     item != cl_qmap_end(&p_updn->p_osm->subn.sw_guid_tbl);
> -	     item = cl_qmap_next(item)) {
> -		p_sw = (osm_switch_t *)item;
> -		/* Clear Min Hop Table */
> -		if (p_subn->opt.connect_roots)
> -			updn_clear_non_root_hops(p_updn, p_sw);
> -		else
> -			osm_switch_clear_hops(p_sw);
> -	}
> +	/* Clear Min Hop Table */
> +	updn_clear_hops(p_updn);
> 
>  	OSM_LOG(p_log, OSM_LOG_VERBOSE,
>  		"Init Min Hop Table of all switches ]\n");
> @@ -598,7 +646,8 @@ static int updn_lid_matrices(void *ctx)
>  			OSM_LOG(&p_updn->p_osm->log, OSM_LOG_ERROR, "ERR : "
>  				"cannot parse root guids file \'%s\'\n",
>  				p_updn->p_osm->subn.opt.root_guid_file);
> -		if (p_updn->p_osm->subn.opt.connect_roots &&
> +		if ((p_updn->p_osm->subn.opt.connect_roots ||
> +		     p_updn->p_osm->subn.opt.connect_switches) &&
>  		    p_updn->num_roots > 1)
>  			osm_ucast_mgr_build_lid_matrices(&p_updn->p_osm->sm.ucast_mgr);
>  	} else {
> -- 
> 1.5.1.4
> 
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