Re: [PATCH net-next] net: hns3: debugfs add dump tm info of nodes, priority and qset

On Tue, 19 Jan 2021 11:14:51 +0800 Huazhong Tan wrote:

On 2021/1/19 3:48, Jakub Kicinski wrote:

quoted

On Mon, 18 Jan 2021 19:20:23 +0800 Huazhong Tan wrote:  

quoted

On 2021/1/17 10:23, Jakub Kicinski wrote:  

quoted

On Fri, 15 Jan 2021 15:09:29 +0800 Huazhong Tan wrote:  

quoted

From: Guangbin Huang <redacted>

To increase methods to dump more tm info, adds three debugfs commands
to dump tm info of nodes, priority and qset. And a new tm file of debugfs
is created for only dumping tm info.

Unlike previous debugfs commands, to dump each tm information, user needs
to enter two commands now. The first command writes parameters to tm and
the second command reads info from tm. For examples, to dump tm info of
priority 0, user needs to enter follow two commands:
1. echo dump priority 0 > tm
2. cat tm

The reason for adding new tm file is because we accepted Jakub Kicinski's
opinion as link https://lkml.org/lkml/2020/9/29/2101. And in order to
avoid generating too many files, we implement write ops to allow user to
input parameters.  

Why are you trying to avoid generating too many files? How many files
would it be? What's the size of each dump/file?  

The maximum number of tm node, priority and qset are 8, 256,
1280, if we create a file for each one, then there are 8 node
files, 256 priority files, 1280 qset files. It seems a little
bit hard for using as well.  

Would the information not fit in one file per type with multiple rows?  

What you means is as below ?

estuary:/debugfs/hns3/0000:7d:00.0$ cat qset

qset id: 0
QS map pri id: 0
QS map link_vld: 1
QS schedule mode: dwrr
QS dwrr: 100

qset id: 1
QS map pri id: 0
QS map link_vld: 0
QS schedule mode: sp
QS dwrr: 0

...

I was thinking more like:

ID	PRI	LINK_VLD	MODE	DWRR
0	0	1		dwrr	0
1	0	0		sp	0
...


but the exact format is up to you.

For example, user want to query qset 1, then all qset info will be output,

I hope you don't mean end user when you say _user_.  This is debugfs,
it's intended for developers to debug issues and system dump to gather 
info at customer site.

there are too many useless info.

So we add an interface to designage the specified id for node, priority 
or qset.

quoted

Can you show example outputs?  

here is the output of this patch.

estuary:/debugfs/hns3/0000:7d:00.0$ echo dump qset 0 > tm
estuary:/debugfs/hns3/0000:7d:00.0$ cat tm
qset id: 0
QS map pri id: 0
QS map link_vld: 1
QS schedule mode: dwrr
QS dwrr: 100

Thanks. Not that much info per entry, as expected. Single file should
do nicely.