[ofa-general] Re: [PATCH] opensm/osm_switch.h: use updated LFT for routing

[Sasha Khapyorsky]

Hi Yevgeny,

On 13:58 Thu 20 Nov     , Yevgeny Kliteynik wrote:
> 
> Function osm_switch_get_port_by_lid() was using the switch's
> LFT, so this LFT might not be updated to recent routing.

I guess it could be only with 'subnet_initialization_error' flag up
(failed LinFwdTbl set will trigger this flag).

> I think that this was also relevant before the LFT simplification.

Yes, logically it should be so, but...

> One immediate outcome of this bug is opensm.fdbs file - when it
> is dumped from the switch LFT (and not from lft_buf),

Why this bug is triggered only now?

> it sometimes
> doesn't match the lst file.

What this "sometimes" mean? I think the case should be investigated
deeper. By such patch we are just trying to hide a possible issue.

As far as I understand opensm.fdbs (and other routing dump) are
generated only after all LinFwdTbl responses are arrived, when some of
them failed 'subnet_initialization_error' flag is up and OpenSM will
resweep. If so why is 'opensm.fdbs' broken? It is not immediately
clear for me.

Sasha

> 
> Signed-off-by: Yevgeny Kliteynik <kliteyn at dev.mellanox.co.il>
> ---
>  opensm/include/opensm/osm_switch.h |    6 +++++-
>  1 files changed, 5 insertions(+), 1 deletions(-)
> 
> diff --git a/opensm/include/opensm/osm_switch.h b/opensm/include/opensm/osm_switch.h
> index caa0bc5..f06931c 100644
> --- a/opensm/include/opensm/osm_switch.h
> +++ b/opensm/include/opensm/osm_switch.h
> @@ -411,7 +411,11 @@ osm_switch_get_port_by_lid(IN const osm_switch_t * const p_sw,
>  {
>  	if (lid_ho == 0 || lid_ho > IB_LID_UCAST_END_HO)
>  		return OSM_NO_PATH;
> -	return p_sw->lft[lid_ho];
> +
> +	if (p_sw->lft_buf)
> +		return p_sw->lft_buf[lid_ho];
> +	else
> +		return p_sw->lft[lid_ho];
>  }
>  /*
>  * PARAMETERS
> -- 
> 1.5.1.4
> 
>