-----Original Message-----
From: oulijun <ouli...@huawei.com>
Sent: Friday, April 9, 2021 14:10
To: linux...@openeuler.org; dev <dev@dpdk.org>; Li, Xiaoyun
<xiaoyun...@intel.com>
Subject: Re: [Linuxarm] Re: [PATCH 2/3] app/testpmd: remove forwarding
config from parsing Rx and Tx
在 2021/4/2 10:33, Li, Xiaoyun 写道:
-----Original Message-----
From: oulijun <ouli...@huawei.com>
Sent: Friday, April 2, 2021 09:45
To: Li, Xiaoyun <xiaoyun...@intel.com>; Yigit, Ferruh
<ferruh.yi...@intel.com>
Cc: dev@dpdk.org; linux...@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 <ouli...@huawei.com>
Sent: Thursday, March 25, 2021 11:04
To: Li, Xiaoyun <xiaoyun...@intel.com>; Yigit, Ferruh
<ferruh.yi...@intel.com>
Cc: dev@dpdk.org; linux...@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 <ouli...@huawei.com>
Sent: Wednesday, March 24, 2021 09:01
To: Li, Xiaoyun <xiaoyun...@intel.com>; Yigit, Ferruh
<ferruh.yi...@intel.com>
Cc: dev@dpdk.org; linux...@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 <ouli...@huawei.com>
Sent: Friday, March 5, 2021 18:22
To: Yigit, Ferruh <ferruh.yi...@intel.com>
Cc: Li, Xiaoyun <xiaoyun...@intel.com>; dev@dpdk.org;
linux...@openeuler.org
Subject: [PATCH 2/3] app/testpmd: remove forwarding config from
parsing Rx and Tx
From: Huisong Li <lihuis...@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().
Hi, Xiaoyun,
The fwd_config_setup() is called when the port is in the stop state and start
state.
When we run "start" cmd, all port are in the start state. Namely, we need to
decide whether to call rte_eth_dev_configure() based on the state of all ports
before rte_eth_dev_get_dcb_info() in dcb_fwd_config_setup().
Modify as follows:
@@ -1834,6 +1834,7 @@ cmd_config_rx_tx_parsed(void *parsed_result,
return;
}
+ fwd_config_setup();
init_port_config();
cmd_reconfig_device_queue(RTE_PORT_ALL, 1, 1); diff --git a/app/test-
pmd/config.c b/app/test-pmd/config.c index bd6ee8b..5981b50 100644
--- a/app/test-pmd/config.c
+++ b/app/test-pmd/config.c
@@ -3179,7 +3179,24 @@ dcb_fwd_config_setup(void)
uint16_t nb_rx_queue, nb_tx_queue;
uint16_t i, j, k, sm_id = 0;
uint16_t total_tc_num = 0;
+ struct rte_port *port;
uint8_t tc = 0;
+ portid_t pid;
+ int ret;
+
+ if (all_ports_stopped()) {
+ /* re-configure the device after changing queue numbers. */
+ for (pid = 0; pid < nb_fwd_ports; pid++) {
+ port = &ports[pid];
+ ret = rte_eth_dev_configure(pid, nb_rxq, nb_txq,
+ &port->dev_conf);
+ if (ret < 0) {
+ printf("Failed to re-configure port %d,
ret = %d.\n",
+ pid, ret);
+ return;
+ }
+ }
+ }
cur_fwd_config.nb_fwd_lcores = (lcoreid_t) nb_fwd_lcores;
cur_fwd_config.nb_fwd_ports = nb_fwd_ports;
But there's still no way to get away with the segment fault for ixgbe and i40e.
1/ For ixgbe, tc mapping is always fixed after DCB is configured. If the number
of queues is reduced, segment fault occur.
Does it mean that the number of queues cannot be modified for ixgbe after
DCB is configured?
2/ For i40e, it appears that the mapping between tc and queue is not updated
after changing queue numbers. From i40e_vsi_config_tc(), its update seems to
depend only on tc_map changes.
please check it?
