Re: [dpdk-dev] [PATCH] ethdev: decrease log level for successful API

[Kevin Traynor <ktraynor@redhat.com>]

On 08/02/2018 01:59 PM, Andrew Rybchenko wrote:
> On 02.08.2018 15:33, Kevin Traynor wrote:
>> Change log level of messages from ERR back to DEBUG where
>> existing API indicates that the condition is a success.
>>
>> This means applications using the API in its current form will
>> not get new ERR logs.
>>
>> Fixes: bea1e0c70cfc ("ethdev: convert static log type usage to dynamic")
>>
>> Signed-off-by: Kevin Traynor <ktraynor@redhat.com>
>> ---
>>   lib/librte_ethdev/rte_ethdev.c | 12 ++++++------
>>   1 file changed, 6 insertions(+), 6 deletions(-)
>>
>> diff --git a/lib/librte_ethdev/rte_ethdev.c
>> b/lib/librte_ethdev/rte_ethdev.c
>> index c7ab157..16656d2 100644
>> --- a/lib/librte_ethdev/rte_ethdev.c
>> +++ b/lib/librte_ethdev/rte_ethdev.c
>> @@ -797,5 +797,5 @@ struct rte_eth_dev *
>>         if (dev->data->rx_queue_state[rx_queue_id] !=
>> RTE_ETH_QUEUE_STATE_STOPPED) {
>> -        RTE_ETHDEV_LOG(ERR,
>> +        RTE_ETHDEV_LOG(DEBUG,
>>               "Queue %"PRIu16" of device with port_id=%"PRIu16"
>> already started\n",
>>               rx_queue_id, port_id);
>> @@ -824,5 +824,5 @@ struct rte_eth_dev *
>>         if (dev->data->rx_queue_state[rx_queue_id] ==
>> RTE_ETH_QUEUE_STATE_STOPPED) {
>> -        RTE_ETHDEV_LOG(ERR,
>> +        RTE_ETHDEV_LOG(DEBUG,
>>               "Queue %"PRIu16" of device with port_id=%"PRIu16"
>> already stopped\n",
>>               rx_queue_id, port_id);
>> @@ -857,5 +857,5 @@ struct rte_eth_dev *
>>         if (dev->data->tx_queue_state[tx_queue_id] !=
>> RTE_ETH_QUEUE_STATE_STOPPED) {
>> -        RTE_ETHDEV_LOG(ERR,
>> +        RTE_ETHDEV_LOG(DEBUG,
>>               "Queue %"PRIu16" of device with port_id=%"PRIu16"
>> already started\n",
>>               tx_queue_id, port_id);
>> @@ -882,5 +882,5 @@ struct rte_eth_dev *
>>         if (dev->data->tx_queue_state[tx_queue_id] ==
>> RTE_ETH_QUEUE_STATE_STOPPED) {
>> -        RTE_ETHDEV_LOG(ERR,
>> +        RTE_ETHDEV_LOG(DEBUG,
>>               "Queue %"PRIu16" of device with port_id=%"PRIu16"
>> already stopped\n",
>>               tx_queue_id, port_id);
>> @@ -1287,5 +1287,5 @@ struct rte_eth_dev *
>>         if (dev->data->dev_started != 0) {
>> -        RTE_ETHDEV_LOG(ERR,
>> +        RTE_ETHDEV_LOG(DEBUG,
>>               "Device with port_id=%"PRIu16" already started\n",
>>               port_id);
>> @@ -1319,5 +1319,5 @@ struct rte_eth_dev *
>>         if (dev->data->dev_started == 0) {
>> -        RTE_ETHDEV_LOG(ERR,
>> +        RTE_ETHDEV_LOG(DEBUG,
>>               "Device with port_id=%"PRIu16" already stopped\n",
>>               port_id);
> 
> I would suggest to use WARNING here. Yes, it is not an error since
> nothing bad has
> happened and we handle duplicate stop and duplicate start,
> but I think it is bad that (buggy?) application does it. Making it debug
> we simply
> hide it too much.
> 

I think an application following the documented API is not bad or buggy.
An application may not maintain some state and always call a stop before
a start etc. in line with the API.

I don't think an API success condition should be changed from a debug
message to anything else. Otherwise, it is trying to flag a warning
about the application which is following the API! It and will just spook
people when they see a new warning.