Re: [PATCH net-next v3] rocker: add debugfs support to dump internal tables

[Murali Karicheri <m-karicheri2@ti.com>]

On 03/17/2016 07:18 PM, Florian Fainelli wrote:
> On 17/03/16 13:48, Murali Karicheri wrote:
>> On 03/17/2016 04:25 PM, Andrew Lunn wrote:
>>> On Thu, Mar 17, 2016 at 04:10:31PM -0400, Murali Karicheri wrote:
>>>> David,
>>>>
>>>> On 08/18/2015 04:47 PM, David Miller wrote:
>>>>> I see some drivers where the foo_debugfs.c file is larger than the rest
>>>>> of the driver.  Once people start using it, it's like crack, and they
>>>>> dump every single debugging widget they found useful at some point into
>>>>> there.
>>>>>
>>>>> This is not what we want.  Most things I see in debugfs support was
>>>>> probably useful for debugging one particular bug but then it was never
>>>>> really useful again in the future.  Those kinds of things can be done
>>>>> locally in someone's tree.
>>>>>
>>>>> I often see various kinds of "statistics" ending up in these things,
>>>>> or register dumps, both of which are 'ethtool' or similar material.
>>>> Very late to this discussion, but I need to port some of the internal code
>>>> to display the content of a ALE (Address Learning Engine) table maintained
>>>> in hardwareat L2 layer. Currently I have a sysfs implementation that dumps
>>>> information like below.
>>>>
>>>> root@k2e-evm:~# cat /sys/devices/platform/soc/2620110.netcp/ale_table
>>>> index 0, raw: 000007fc d000ffff ffffffff, type: addr(1), addr: ff:ff:ff:ff:ff:ff, mcstate: f(3), port mask: 1ff, no super
>>>> index 1, raw: 00000000 10000800 28329a1c, type: addr(1), addr: 08:00:28:32:9a:1c, uctype: persistent(0), port: 0
>>>> index 2, raw: 000007fc d0000100 5e000001, type: addr(1), addr: 01:00:5e:00:00:01, mcstate: f(3), port mask: 1ff, no super
>>>> index 19, raw: 00000004 d000d4be d93db6c1, type: addr(1), addr: d4:be:d9:3d:b6:c1, uctype: touched(3), port: 1
>>>>
>>>> What is the available interface in kernel to expose this information
>>>> to user space as debugfs is not suggested based on this thread?
>>>
>>> This looks a lot like what the mv88e6xxx_port_fdb_dump() callback
>>> returns to DSA when SWITCHDEV_OBJ_ID_PORT_FDB is passed to
>>> switchdev_port_obj_dump() in the switchdev ops.
>>>
>> Andrew,
>>
>> Which tool user has to use to get this dump once implemented?
> 
> iproute2's bridge command with bridge fdb show <interface>.
> 
Thanks

-- 
Murali Karicheri
Linux Kernel, Keystone