RE: [PATCH] app/testpmd: fix secondary process cannot dump packet

["Zhang, Peng1X" <peng1x.zhang@intel.com>]

Hi,
In fact, the patch is aim to fix this issue that secondary process cannot dump packet after start testpmd. 
This issue is induced by commit id is 3c4426db54fc ("app/testpmd: do not poll stopped queues"). After 
secondary process start, the default value of Rx/Tx queue state maintained by testpmd is 
'RTE_ETH_QUEUE_STATE_STOPPED', the 'fsm[sm_id]->disabled' flag will set true according to queues 
state, then packet cannot forward and dump. 

The reason why not use 'dev->data->rx_queue_state' is whether queue state is start or stop in primary 
process depend on rx_conf->rx_deferred_start after start testpmd. And after having started testpmd, 
queue state can be controlled by command for example 'port x rxq x start'. 
Should we align with the same behavior of queues state for primary and secondary process after start testpmd?   

> -----Original Message-----
> From: lihuisong (C) <lihuisong@huawei.com>
> Sent: Wednesday, June 29, 2022 10:55 AM
> To: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>; Zhang, Peng1X
> <peng1x.zhang@intel.com>; dev@dpdk.org
> Cc: Singh, Aman Deep <aman.deep.singh@intel.com>; Zhang, Yuying
> <yuying.zhang@intel.com>; stable@dpdk.org
> Subject: Re: [PATCH] app/testpmd: fix secondary process cannot dump packet
> 
> 
> 在 2022/6/23 20:10, Andrew Rybchenko 写道:
> > On 6/23/22 21:15, peng1x.zhang@intel.com wrote:
> >> From: Peng Zhang <peng1x.zhang@intel.com>
> >>
> >> The origin design is whether testpmd is primary or not, if state of
> >> receive queue is stop, then packets will not be dumped for show.
> >> While to secondary process, receive queue will not be set up, and
> >> state will still be stop even if testpmd is started. So packets of
> >> stated secondary process cannot be dumped for show.
> >>
> >> The current design is to secondary process state of queue will be set
> >> to start after testpmd is started. Then packets of started secondary
> >> process can be dumped for show.
> >>
> >> Fixes: a550baf24af9 ("app/testpmd: support multi-process")
> >> Cc: stable@dpdk.org
> >>
> >> Signed-off-by: Peng Zhang <peng1x.zhang@intel.com>
> >> ---
> >>   app/test-pmd/testpmd.c | 12 ++++++++++++
> >>   1 file changed, 12 insertions(+)
> >>
> >> diff --git a/app/test-pmd/testpmd.c b/app/test-pmd/testpmd.c index
> >> 205d98ee3d..93ba7e7c9b 100644
> >> --- a/app/test-pmd/testpmd.c
> >> +++ b/app/test-pmd/testpmd.c
> >> @@ -3007,6 +3007,18 @@ start_port(portid_t pid)
> >>               if (setup_hairpin_queues(pi, p_pi, cnt_pi) != 0)
> >>                   return -1;
> >>           }
> >> +
> >> +        if (port->need_reconfig_queues > 0 && !is_proc_primary()) {
> >> +            struct rte_eth_rxconf *rx_conf;
> >> +            for (qi = 0; qi < nb_rxq; qi++) {
> >> +                rx_conf = &(port->rxq[qi].conf);
> >> +                ports[pi].rxq[qi].state =
> >> +                    rx_conf->rx_deferred_start ?
> >> +                    RTE_ETH_QUEUE_STATE_STOPPED :
> >> +                    RTE_ETH_QUEUE_STATE_STARTED;
> >
> > I'm not sure why it is correct to assume that deferred queue is not
> > yet started.
> +1.
> 
> We should also consider whether the queue state can be changed in secondary.
> The 'rx_conf->rx_deferred_start' is the data in secondary.
> Why not use 'dev->data->rx_queue_state[]'.
> 
> In fact, the issue you memtioned was introduced the following patch:
> Fixes: 3c4426db54fc ("app/testpmd: do not poll stopped queues")
> 
> The root cause of this issue is that the default value of Rx/Tx queue state
> maintained by testpmd is 'RTE_ETH_QUEUE_STATE_STOPPED'. As a result,
> secondary doesn't start polling thread to receive packets when start packet
> forwarding. And now, secondary cannot receive and send any packets.
> 
> Could you fix it together?
> >
> >> +            }
> >> +        }
> >> +
> >>           configure_rxtx_dump_callbacks(verbose_level);
> >>           if (clear_ptypes) {
> >>               diag = rte_eth_dev_set_ptypes(pi, RTE_PTYPE_UNKNOWN,
> >
> > .