Re: [PATCH] app/testpmd: remove invalid ports when other process detach

[fengchengwen <fengchengwen@huawei.com>]

On 2022/3/2 16:26, Thomas Monjalon wrote:
> 02/03/2022 03:33, Chengwen Feng:
>> Start main and secondary process:
>> ./dpdk-testpmd -a BDF0 -a BDF1 --proc-type=auto -- -i --rxq=8 --txq=8
>> 	--num-procs=2 --proc-id=0
>> ./dpdk-testpmd -a BDF0 -a BDF1 --proc-type=auto -- -i --rxq=8 --txq=8
>> 	--num-procs=2 --proc-id=1
>> Execute following command in main process:
>> 	port stop 0
>> 	port detach 0
>> Execute following command in secondary process:
>> 	set fwd mac
>> 	start
>> The secondary process will display:
>> 	Invalid port_id=0
>> 	telcore 19 called rx_pkt_burst for not ready port 0
>> 	stpmd> 8: [/lib64/libc.so.6(+0xdf600) [0xffff9e1dc600]]
>> 	7: [/lib64/libpthread.so.0(+0x7c48) [0xffff9e28ac48]]
>> 	6: [/usr/app/testpmd(eal_thread_loop+0x2c4) [0xb23574]]
>> 	5: [/usr/app/testpmd() [0x9c21d8]]
>> 	4: [/usr/app/testpmd() [0x9c2108]]
>> 	3: [/usr/app/testpmd() [0x9b6cf0]]
>> 	2: [/usr/app/testpmd() [0xad8620]]
>> 	1: [/usr/app/testpmd(rte_dump_stack+0x20) [0xb1a130]]
>>
>> The root cause it that the secondary process has not removed invalid
>> ports when it processes RTE_ETH_EVENT_DESTROY event.
> 
> Why the ports are not removed?

Testpmd register function eth_event_callback to deal with DESTROY event,
currently it only assign ports[port_id].port_status with RTE_PORT_CLOSED, it
doesn't update other global variables like nb_ports.

> 
>> This patch adds a delay remove invalid ports invoke when process the
>> RTE_ETH_EVENT_DESTROY event.
> 
> Why do we need this delay?

The remove_invalid_ports will scan rte_eth_devices[], when process the DESTROY
event, the rte_eth_devices[x] still valid, so here we should a delay logic.

> 
> [...]
>> +static void
>> +remove_invalid_ports_callback(void *arg)
>> +{
>> +	RTE_SET_USED(arg);
>> +	remove_invalid_ports();
>> +}
> [...]
>>  	case RTE_ETH_EVENT_DESTROY:
>>  		ports[port_id].port_status = RTE_PORT_CLOSED;
>>  		printf("Port %u is closed\n", port_id);
>> +		if (rte_eal_alarm_set(100000, remove_invalid_ports_callback,
>> +				(void *)(intptr_t)port_id))
>> +			fprintf(stderr,
>> +				"Could not set up deferred device released\n");
>>  		break;
> 
> 
> 
> 
> .
>