On 5/17/22 1:31 AM, Jason Gunthorpe wrote:
On Mon, May 16, 2022 at 11:14:24PM +0800, Cheng Xu wrote:
I think this twice, use a net notifier of module can not solve this, due
to the leak of all ib devices information in erdma module.
I don't understand what this means
At first I want to register a global net notifier in our module, and link
the ib device and net device if matches in the callback. But in the
callback, we can not get the ib devices registered by erdma, because our
driver module does not maintain the ib device list. This is not the
right way.
The core has the device list, if you need to search it then you need
to add a new searching function
I had a mistake, instead of what I said, erdma should search net devices
in a wq to find the matched net device. Not search ib devices in net
notifier callback.
I think is should be fine.
The solution may be simple: register net notifier per device in probe,
and call ib_device_set_netdev if matches in the notifier callback.
That sounds wrong
OK. So using rdma link command to handle the link relationship manually
is still a better choice？
No
Actually, erdma looks like a hardware implementation of siw/rxe (more
likes siw, because erdma uses iWarp, and have similar CM
implementation): the ethernet functionality is provided by existed net
device, no matter what kind of the net device (due to virtio-net is
de-facto in cloud virtualization, erdma is binded to virtio-net in
practice). Due to this similarity, siw/rxe use 'rdma link' to link the
ib device and net device (including create ib device), Does it sound
reasonable that erdma use it to link the net deivce?
It is not like siw because it cannot run on any netdevice, it can only
run on the signle netdevice the HW is linked to in the background.
Yeah, you are exactly right, I omitted this detail in the last
reply.
Thanks,
Cheng Xu
Jason
