Re: [dpdk-dev] [PATCH v4] lpm: skip table entries update if rules found

["Medvedkin, Vladimir" <vladimir.medvedkin@intel.com>]

Hi Yangchao,

Thanks for the patch.
This might be useful for control plane implementations that don't track 
inserted routes.
I have just a one nit inlined below. Also, could you do the same for lpm6?

P.S. Please have a look at rte_fib library, there are more optimizations 
compared to lpm library.

Apart from that,
Acked-by: Vladimir Medvedkin <vladimir.medvedkin@intel.com>

On 20/04/2020 03:48, Yangchao Zhou wrote:
> Table entries do not need to be updated if the same rules can be found.
>
> Signed-off-by: Yangchao Zhou <zhouyates@gmail.com>
> ---
> v1-v2: Skip updating when the next hop is the same as the current one
> v2-v4: Coding style fix
> ---
>   lib/librte_lpm/rte_lpm.c | 9 +++++++++
>   1 file changed, 9 insertions(+)
>
> diff --git a/lib/librte_lpm/rte_lpm.c b/lib/librte_lpm/rte_lpm.c
> index 268756419..b8a90e385 100644
> --- a/lib/librte_lpm/rte_lpm.c
> +++ b/lib/librte_lpm/rte_lpm.c
> @@ -285,6 +285,9 @@ rule_add(struct rte_lpm *lpm, uint32_t ip_masked, uint8_t depth,
>   
>   			/* If rule already exists update its next_hop and return. */
>   			if (lpm->rules_tbl[rule_index].ip == ip_masked) {
> +
> +				if (lpm->rules_tbl[rule_index].next_hop == next_hop)


Line over 80 characters, please split it by two.

> +					return -EEXIST;
>   				lpm->rules_tbl[rule_index].next_hop = next_hop;
>   
>   				return rule_index;
> @@ -674,6 +677,12 @@ rte_lpm_add(struct rte_lpm *lpm, uint32_t ip, uint8_t depth,
>   	/* Add the rule to the rule table. */
>   	rule_index = rule_add(lpm, ip_masked, depth, next_hop);
>   
> +	/* Skip table entries update if The rule is the same as
> +	 * the rule in the rules table.
> +	 */
> +	if (rule_index == -EEXIST)
> +		return 0;
> +
>   	/* If the is no space available for new rule return error. */
>   	if (rule_index < 0) {
>   		return rule_index;

-- 
Regards,
Vladimir