[dpdk-dev] [PATCH v2 1/2] app/testpmd: add link speed check before port start

[Li, Xiaoyun]

> -----Original Message-----
> From: Huisong Li <lihuisong at huawei.com>
> Sent: Tuesday, May 4, 2021 09:46
> To: Li, Xiaoyun <xiaoyun.li at intel.com>
> Cc: Yigit, Ferruh <ferruh.yigit at intel.com>; dev at dpdk.org
> Subject: Re: [dpdk-dev] [PATCH v2 1/2] app/testpmd: add link speed check
> before port start
> 
> 
> 在 2021/4/30 12:46, Li, Xiaoyun 写道:
> >
> >> -----Original Message-----
> >> From: Huisong Li <lihuisong at huawei.com>
> >> Sent: Friday, April 30, 2021 12:04
> >> To: Li, Xiaoyun <xiaoyun.li at intel.com>
> >> Cc: Yigit, Ferruh <ferruh.yigit at intel.com>; dev at dpdk.org
> >> Subject: Re: [dpdk-dev] [PATCH v2 1/2] app/testpmd: add link speed
> >> check before port start
> >>
> >>
> >> 在 2021/4/30 11:19, Li, Xiaoyun 写道:
> >>>> -----Original Message-----
> >>>> From: Min Hu (Connor) <humin29 at huawei.com>
> >>>> Sent: Wednesday, April 28, 2021 16:37
> >>>> To: dev at dpdk.org
> >>>> Cc: Yigit, Ferruh <ferruh.yigit at intel.com>; Li, Xiaoyun
> >>>> <xiaoyun.li at intel.com>
> >>>> Subject: [PATCH v2 1/2] app/testpmd: add link speed check before
> >>>> port start
> >>>>
> >>>> From: Huisong Li <lihuisong at huawei.com>
> >>>>
> >>>> Currently, to check whether the configured link_speeds is valid, we
> >>>> have to run "port start". In addition, if the configuration fails,
> >>>> "port-
> >>> dev_conf.link_speeds"
> >>>> maintained in testpmd cannot be restored.
> >>>>
> >>>> This patch adds the link_speeds check before port start by calling
> >>>> dev_configure, and resolves these problems.
> >>> Not sure about this patch. I don't think you can fix the issue you mentioned.
> >>> Probably only hns3 does speed check in dev_configure. I don't see
> >>> this in other
> >> drivers, not in i40e/ice/mlx.
> >>> I guess it's because if it's not supported speed, it will just be
> >>> UNKNOWN and
> >> user can config again?
> >>
> >> I think that the validity of the configuration delivered by
> >> dev_configure is ensured by this interface and cannot be left to the backend.
> >>
> >> Because it facilitates users to handle abnormal configurations in a
> >> timely manner. It may be more appropriate for the driver to do this
> >> check in dev_configure.
> > I still think it's not necessary.
> 
> ok😂
> 
> @Ferruh, what do you think?
> 
> >
> >> In addition, even if other drivers do not add this check in
> >> dev_configure, this patch does not seem to affect the current behavior of
> these drivers.
> >>
> >>> BTW, even if this behavior is accepted by others, still some comments below.
> >>>
> >>>> Signed-off-by: Huisong Li <lihuisong at huawei.com>
> >>>> Signed-off-by: Min Hu (Connor) <humin29 at huawei.com>
> >>>> ---
> >>>>    app/test-pmd/cmdline.c | 42
> >>>> ++++++++++++++++++++++++++++++++++++++++-
> >>>> -
> >>>>    1 file changed, 40 insertions(+), 2 deletions(-)
> >>>>
> >>>> diff --git a/app/test-pmd/cmdline.c b/app/test-pmd/cmdline.c index
> >>>> 5fdcc1c..ddbc629 100644
> >>>> --- a/app/test-pmd/cmdline.c
> >>>> +++ b/app/test-pmd/cmdline.c
> >>>> @@ -1549,8 +1549,12 @@ cmd_config_speed_all_parsed(void
> >> *parsed_result,
> >>>>    			__rte_unused void *data)
> >>>>    {
> >>>>    	struct cmd_config_speed_all *res = parsed_result;
> >>>> +	uint32_t old_link_speeds[RTE_MAX_ETHPORTS];
> >>>> +	struct rte_port *port;
> >>>>    	uint32_t link_speed;
> >>>>    	portid_t pid;
> >>>> +	portid_t i;
> >>>> +	int ret;
> >>>>
> >>>>    	if (!all_ports_stopped()) {
> >>>>    		printf("Please stop all ports first\n"); @@ -1562,7 +1566,26
> >>>> @@ cmd_config_speed_all_parsed(void *parsed_result,
> >>>>    		return;
> >>>>
> >>>>    	RTE_ETH_FOREACH_DEV(pid) {
> >>>> -		ports[pid].dev_conf.link_speeds = link_speed;
> >>>> +		port = &ports[pid];
> >>>> +		old_link_speeds[pid] = port->dev_conf.link_speeds;
> >>>> +		port->dev_conf.link_speeds = link_speed;
> >>>> +		ret = rte_eth_dev_configure(pid, nb_rxq, nb_txq,
> >>>> +					    &port->dev_conf);
> >>>> +		if (ret < 0) {
> >>>> +			printf("Failed to check link speeds for port %d, ret
> >>>> = %d.\n",
> >>>> +				pid, ret);
> >>>> +			goto roolback;
> >>> Why don't you just add restoring all ports speed here and then
> >>> "break"? No
> >> matter one dev fails or not, all ports will do reconfig from your code logic.
> >>> And you type rollback wrongly.
> >> It cannot exit directly after restoring all ports speed. If the cmd
> >> fails to execute, it is necessary to reconfigure device with the correct
> configuration.
> >>    Because "nb_rx/tx_queues" in dev->data are cleared to zero if
> >> dev_configure fails to be executed in PMD driver.
> > ?
> > cmd_reconfig_device_queue(RTE_PORT_ALL, 1, 1); is at the end of this cmd.
> This will re-config all ports.
> > I don't understand why can't you add a restoring in this if and break this loop
> and do this reconfig.
> What do you mean? If a port fails among all ports, only the failed port is
> restored and reconfigured. I suppose that's what you mean?
> The cmd "port config all speed xxx duplex xxx" applies to all ports. If it fails to be
> delivered, the user considers that the cmd does not take effect.
> So it is necessary to restore and reconfigure all ports to the previous state.

You still don't understand me. See below. I mean the following.
You don't need to got to rollback. Because "cmd_reconfig_device_queue(RTE_PORT_ALL, 1, 1);" will config all ports anyway already no matter you restore speeds or not.
Can you read the code carefully? "cmd_reconfig_device_queue(RTE_PORT_ALL, 1, 1);" is always there and it configs ALL ports.

static void
cmd_config_speed_all_parsed(void *parsed_result,
			__rte_unused struct cmdline *cl,
			__rte_unused void *data)
{
	struct cmd_config_speed_all *res = parsed_result;
	uint32_t link_speed;
	portid_t pid;

	if (!all_ports_stopped()) {
		printf("Please stop all ports first\n");
		return;
	}

	if (parse_and_check_speed_duplex(res->value1, res->value2,
			&link_speed) < 0)
		return;

	RTE_ETH_FOREACH_DEV(pid) {
-		ports[pid].dev_conf.link_speeds = link_speed;
+		port = &ports[pid];
+		old_link_speeds[pid] = port->dev_conf.link_speeds;
+		port->dev_conf.link_speeds = link_speed;
+		ret = rte_eth_dev_configure(pid, nb_rxq, nb_txq,
+					    &port->dev_conf);
+		if (ret < 0) {
+			printf("Failed to check link speeds for port %d, ret = %d.\n",
+				pid, ret);
+			for (i = 0; i <= pid; i++) {
+				port = &ports[i];
+				port->dev_conf.link_speeds = old_link_speeds[i];
+			}
+			break;
+		}
	}

	cmd_reconfig_device_queue(RTE_PORT_ALL, 1, 1);
}

> >
> >>>> +		}
> >>>> +	}
> >>>> +
> >>>> +	cmd_reconfig_device_queue(RTE_PORT_ALL, 1, 1);
> >>>> +
> >>>> +	return;
> >>>> +
> >>>> +roolback:
> >>>> +	for (i = 0; i <= pid; i++) {
> >>>> +		port = &ports[i];
> >>>> +		port->dev_conf.link_speeds = old_link_speeds[i];
> >>>>    	}
> >>>>
> >>>>    	cmd_reconfig_device_queue(RTE_PORT_ALL, 1, 1); @@ -1621,7
> >>>> +1644,10 @@ cmd_config_speed_specific_parsed(void *parsed_result,
> >>>>    				__rte_unused void *data)
> >>>>    {
> >>>>    	struct cmd_config_speed_specific *res = parsed_result;
> >>>> +	uint32_t old_link_speeds;
> >>>> +	struct rte_port *port;
> >>>>    	uint32_t link_speed;
> >>>> +	int ret;
> >>>>
> >>>>    	if (!all_ports_stopped()) {
> >>>>    		printf("Please stop all ports first\n"); @@ -1635,8 +1661,20
> >>>> @@ cmd_config_speed_specific_parsed(void *parsed_result,
> >>>>    			&link_speed) < 0)
> >>>>    		return;
> >>>>
> >>>> -	ports[res->id].dev_conf.link_speeds = link_speed;
> >>>> +	port = &ports[res->id];
> >>>> +	old_link_speeds = port->dev_conf.link_speeds;
> >>>> +	port->dev_conf.link_speeds = link_speed;
> >>>> +	ret = rte_eth_dev_configure(res->id, nb_rxq, nb_txq,
> >>>> +				    &port->dev_conf);
> >>>> +	if (ret < 0) {
> >>>> +		printf("Failed to check link speeds for port %d, ret = %d.\n",
> >>>> +			res->id, ret);
> >>>> +		port->dev_conf.link_speeds = old_link_speeds;
> >>>> +	}
> >>>>
> >>>> +	/*
> >>>> +	 * If the cmd fails to execute, it is necessary to reconfigure device.
> >>>> +	 */
> >>>>    	cmd_reconfig_device_queue(RTE_PORT_ALL, 1, 1);  }
> >>>>
> >>>> --
> >>>> 2.7.4
> >>> .