Re: [dpdk-dev] [PATCH v3 3/3] app/testpmd: fix dynamic config error

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 1/22/2021 5:04 PM, Ferruh Yigit wrote:
> On 1/22/2021 9:01 AM, Steve Yang wrote:
>> The offloads of 'tx/rx_conf' didn't keep up with the corresponding
>> offloads of 'dev_conf' if rx queue capability was 0, it would cause
>> the configuration invalid.
>>
>> For example:
>> Configuring 'max-pkt-len' would change 'rx_offloads' in dev_conf while
>> rx_conf.offloads of each queue still kept the old value.
>> It would cause the failure of offloads check in 'rte_eth_rx_queue_setup'.
>>
>> This patch applied tx/rx offloads configuration for each queue
>> once it changed and corresponding tx/rx queue capability was 0.
>>
>> Fixes: 5e91aeef218c ("app/testpmd: fix offload flags after port config")
>>
>> Signed-off-by: Steve Yang <stevex.yang@intel.com>
>> ---
>>   app/test-pmd/testpmd.c | 12 ++++++++++--
>>   1 file changed, 10 insertions(+), 2 deletions(-)
>>
>> diff --git a/app/test-pmd/testpmd.c b/app/test-pmd/testpmd.c
>> index a2c9aad960..8307c7f9e9 100644
>> --- a/app/test-pmd/testpmd.c
>> +++ b/app/test-pmd/testpmd.c
>> @@ -3296,7 +3296,11 @@ rxtx_port_config(struct rte_port *port)
>>       for (qid = 0; qid < nb_rxq; qid++) {
>>           offloads = port->rx_conf[qid].offloads;
>>           port->rx_conf[qid] = port->dev_info.default_rxconf;
>> -        if (offloads != 0)
>> +        if (port->dev_info.rx_queue_offload_capa == 0 &&
>> +            offloads != port->dev_conf.rxmode.offloads)
>> +            port->rx_conf[qid].offloads =
>> +                port->dev_conf.rxmode.offloads;
>> +        else if (offloads != 0)
>>               port->rx_conf[qid].offloads = offloads;
> 
> I am still concerned to use port offloads to set the queue specific offloads, 
> this may lead unexpected result.
> 
> Below is what Steve provided as reproduce steps [1], I think that is application 
> (testpmd) miss-configuration to update 'max-pkt-len' but not update the 
> JUMBO_FRAME offload flag and MTU accordingly.
> 
> What do you think update the JUMBO_FRAME offload flag (both for port and queues) 
> according and set MTU according on the testpmd command where 'max-pkt-len' is 
> set? This is more like your first version.
> 
> 
> 
> [1]
> ----------------------------------------------
> # x86_64-native-linuxapp-gcc/app/dpdk-testpmd  -c 0xf -n 4  -- -i 
> --max-pkt-len=9000 --tx-offloads=0x8000 --rxq=4 --txq=4 --disable-rss
> testpmd>  set verbose 3
> testpmd>  start
> testpmd>  stop
> testpmd>  port stop all
> testpmd>  port config all max-pkt-len 1518
> testpmd> port start all
> Configuring Port 0 (socket 1)
> Ethdev port_id=0 rx_queue_id=0, new added offloads 0x800 must be within 
> per-queue offload capabilities 0x0 in rte_eth_rx_queue_setup()
> Fail to configure port 0 rx queues//<-- Fail error info;
> ------------------------------------------------
> 

Indeed first patch of this series solves the MTU problem with "port config all 
max-pkt-len" command (although it ignores 'max_rx_pkt_len' is only valid when 
JUMBO_FRAME flag is set)

And second patch updates the JUMBO_FRAME flag in the command function, same as I 
suggested above.
Only if second patch extended to update JUMBO_FRAME flag for all queues in 
'update_jumbo_frame_offload()', this patch can be dropped, what do you think?