Re: [dpdk-dev] [PATCH] ethdev: remove deprecated shared counter attribute

[Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>]

On 9/28/21 6:58 PM, Stephen Hemminger wrote:
> On Tue, 28 Sep 2021 18:23:00 +0300
> Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru> wrote:
> 
>> @@ -2498,24 +2498,11 @@ struct rte_flow_query_age {
>>   * Counters can be retrieved and reset through ``rte_flow_query()``, see
>>   * ``struct rte_flow_query_count``.
>>   *
>> - * @deprecated Shared attribute is deprecated, use generic
>> - * RTE_FLOW_ACTION_TYPE_INDIRECT action.
>> - *
>> - * The shared flag indicates whether the counter is unique to the flow rule the
>> - * action is specified with, or whether it is a shared counter.
>> - *
>> - * For a count action with the shared flag set, then then a global device
>> - * namespace is assumed for the counter id, so that any matched flow rules using
>> - * a count action with the same counter id on the same port will contribute to
>> - * that counter.
>> - *
>>   * For ports within the same switch domain then the counter id namespace extends
>>   * to all ports within that switch domain.
>>   */
>>  struct rte_flow_action_count {
>> -	/** @deprecated Share counter ID with other flow rules. */
>> -	uint32_t shared:1;
>> -	uint32_t reserved:31; /**< Reserved, must be zero. */
>> +	uint32_t reserved; /**< Reserved, must be zero. */
>>  	uint32_t id; /**< Counter ID. */
> 
> Reserved fields are often source of future problems.
> You should change each driver to check that reserved field
> return -ENOTSUP if non-zero.  That way if reserved field is ever
> used in future it won't break API/ABI.
> 
> The other option is to just remove the reserved field and take the API/ABI
> hit now.
> 

I agree. If there is no objections, I'll remove it in v2.