Re: [dpdk-dev] [PATCH] table: fix table_array for incomplete bitmask

[Bruce Richardson <bruce.richardson@intel.com>]

On Thu, Dec 04, 2014 at 02:23:33PM +0000, Bruce Richardson wrote:
> Hi Cristian, please review before I send out publically. Thanks. B.
> -------------------------
> 
> When a lookup was done on a table_array structure with an incomplete
> bitmask, the results was always zero hits. This was because the
> pkts_mask value was cleared as we process each entry, and the result
> was assigned at the end of the loop, when pkts_mask was zero.
> Changing the assignment to occur at the start, before the pkts_mask
> gets cleared, fixes this issue.
> 
> Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>

Self-nak on this copy, please see follow-on without the review request to Cristian
(who can hopefully ack this soon :-) )

> ---
>  lib/librte_table/rte_table_array.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/lib/librte_table/rte_table_array.c b/lib/librte_table/rte_table_array.c
> index 0b1d42a..4d3c05e 100644
> --- a/lib/librte_table/rte_table_array.c
> +++ b/lib/librte_table/rte_table_array.c
> @@ -164,6 +164,8 @@ rte_table_array_lookup(
>  {
>  	struct rte_table_array *t = (struct rte_table_array *) table;
>  
> +	*lookup_hit_mask = pkts_mask;
> +
>  	if ((pkts_mask & (pkts_mask + 1)) == 0) {
>  		uint64_t n_pkts = __builtin_popcountll(pkts_mask);
>  		uint32_t i;
> @@ -190,8 +192,6 @@ rte_table_array_lookup(
>  		}
>  	}
>  
> -	*lookup_hit_mask = pkts_mask;
> -
>  	return 0;
>  }
>  
> -- 
> 1.9.3
>