-----Original Message----- From: oulijun oulijun@huawei.com Sent: Friday, April 2, 2021 09:45 To: Li, Xiaoyun xiaoyun.li@intel.com; Yigit, Ferruh ferruh.yigit@intel.com Cc: dev@dpdk.org; linuxarm@openeuler.org Subject: Re: [PATCH 2/3] app/testpmd: remove forwarding config from parsing Rx and Tx
在 2021/3/29 9:53, Li, Xiaoyun 写道:
-----Original Message----- From: oulijun oulijun@huawei.com Sent: Thursday, March 25, 2021 11:04 To: Li, Xiaoyun xiaoyun.li@intel.com; Yigit, Ferruh ferruh.yigit@intel.com Cc: dev@dpdk.org; linuxarm@openeuler.org Subject: Re: [PATCH 2/3] app/testpmd: remove forwarding config from parsing Rx and Tx
在 2021/3/24 9:44, Li, Xiaoyun 写道:
-----Original Message----- From: oulijun oulijun@huawei.com Sent: Wednesday, March 24, 2021 09:01 To: Li, Xiaoyun xiaoyun.li@intel.com; Yigit, Ferruh ferruh.yigit@intel.com Cc: dev@dpdk.org; linuxarm@openeuler.org Subject: Re: [PATCH 2/3] app/testpmd: remove forwarding config from parsing Rx and Tx
在 2021/3/23 15:50, Li, Xiaoyun 写道:
Hi
> -----Original Message----- > From: Lijun Ou oulijun@huawei.com > Sent: Friday, March 5, 2021 18:22 > To: Yigit, Ferruh ferruh.yigit@intel.com > Cc: Li, Xiaoyun xiaoyun.li@intel.com; dev@dpdk.org; > linuxarm@openeuler.org > Subject: [PATCH 2/3] app/testpmd: remove forwarding config from > parsing Rx and Tx > > From: Huisong Li lihuisong@huawei.com >
The commit message should be more simple and avoids grammar
mistakes.
All right, I will simply it.
> The "fwd_config_setup()" function does release and apply for > memory of forwarding flows, and re-establish these streams when > rxq/txq or rxd/txd is changed. The function is also called by > "start_packet_forwarding()" when user executes "start" cmd. > All changes for rxq/txq or rxd/txd can be updated uniformly when > this command is executed. Therefore, it is a little redundant in > the
"cmd_config_rx_tx_parsed"
> function.
It's not redundant. This command may configure number of rxq/txq. So the
fwd streams map may change.
Then it's common to check the fwd streams after this command using "show
config fwd".
If you remove this fwd stream update, users can't get the correct new fwd
streams until they start the traffic.
But they may change a lot of things and want to check if the setting is correct
before they start the traffic.
Yes, you are right. It's really unfriendly.
> > In addition, the forwarding stream under one TC is configured > based on number of queues allocated to TC. And number of queues > allocated to TC is updated after calling "rte_eth_dev_configure" > again. If the number of queues is reduced after configuring the > DCB, and then, release and apply for stream memory, and > reinitialize the forwarding stream under the DCB mode based on > the old TC
information.
> As a result, null pointer may be accessed.
I think you should add "rte_eth_dev_configure " into dcb_fwd_config_setup()
before rte_eth_dev_get_dcb_info().
And the commit message should be similar like the following: Segment fault might happen after configuring queue number to less because
dcb_fwd_config_setup setup dcb based on old dcb info.
And dcb info can only update after rte_eth_dev_configure(). So this patch adds rte_eth_dev_configure() before rte_eth_dev_get_dcb_info()
to get updated dcb info to fix this issue.
Thank you for your advice. But the above adjustments may still not work for some drivers. The mapping between queues and TCs in these drivers is updated in the dev_start stage.
I have an idea. We can move fwd_config_setup() to start_port(), which is called by main() and after starting ports This not only solves the segment fault, but also does not have the problem you mentioned above. I
test it and it is ok.
What do you think, xiaoyun?
How can you fix the issue I mentioned? You still need to start port first to see the updated fwd config.
Yes. But it can make sure that users get the correct new fwd streams before executing the 'start' command.
And for those drivers, why does the mapping has to be updated in dev_start
stage?
What does it need? Can't it be moved to dev_configure?
The framework does not require that the configuration parameters transferred by the dev_configure API must be updated in the interface of driver. The driver can verify the correctness of these parameters in the interface, and then complete the update in the dev_start stage. It depends on the design and need of the driver. Maybe it's more appropriate to put it in dev_configure, but now we can't ask all these
drivers to modify the operation.
I still think it's driver's responsibility to configure DCB in dev_configure.
Calling fwd_config_setup here is because this command changes queue
number. Users just change queue number so want to check fwd setup. It's a normal and reasonable behavior.
Starting port will be called in many situations. I don't think it's appropriate to
call fwd_config_setup every time calling port_start. And you can't expect users know the fwd setup only change after port_start.
These are only my thoughts. If anyone else agrees you, they can give you ack.
@Ferruh, what do you think? Currently, both ixgbe and i40e also have this problem. Even if testpmd can be modified according to Xiaoyun's suggestion, and the driver is not modified, this problem still exists in some drivers, such as ixgbe and hns3.
NO. I40e and ixgbe DON'T have the issue. I40e tc mapping is done in dev_configure. ixgbe tc mapping is always fixed due to hw design. It only needs dev_configure to get dcb_conf info. No matter you configure dcb or not, the mapping is always the same. You can check ixgbe_dev_get_dcb_info().
So for i40e and ixgbe, you only need to add dev_configure in dcb_fwd_config_setup().
> > Like: > set nbcore 4 > port stop all > port config 0 dcb vt off 4 pfc on port start all port stop all > port config all rxq 8 port config all txq 8 > > At the moment, a segmentation fault occurs. > > Fixes: ce8d561418d4 ("app/testpmd: add port configuration > settings") > Cc: stable@dpdk.org > > Signed-off-by: Huisong Li lihuisong@huawei.com > Signed-off-by: Lijun Ou oulijun@huawei.com > --- > V1->V2: > - use stream instead of flow > --- > app/test-pmd/cmdline.c | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/app/test-pmd/cmdline.c b/app/test-pmd/cmdline.c > index 4df0c32..e316f5c 100644 > --- a/app/test-pmd/cmdline.c > +++ b/app/test-pmd/cmdline.c > @@ -1837,8 +1837,6 @@ cmd_config_rx_tx_parsed(void
*parsed_result,
> return; > } > > - fwd_config_setup(); > - > init_port_config(); > > cmd_reconfig_device_queue(RTE_PORT_ALL, 1, 1); > -- > 2.7.4
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