[dm-devel] [PATCH] multipathd: handle fpin events

[Martin Wilck]

On Mon, 2021-12-13 at 14:28 +0530, Muneendra Kumar M wrote:
> Hi  Martin,
> 
> > However I am really thrilled by the prospect of generalizing event
> handling and reusing the uevent threads for FPIN. That would reduce
> complexity a lot, which is a good thing IMO.
> 
> I have a query with respect to generalizing event handling and
> reusing the
> uevent threads  .
> Please correct me if iam wrong.
> 
> FPIN events work on NETLINK_SCSITRANSPORT
>         netlink_kernel_create(&init_net, NETLINK_SCSITRANSPORT, 
> &cfg);
> ==>scsi_netlink.c
> 
> whereas uvents  works on NETLINK_KOBJECT_UEVENT.
>            netlink_kernel_create(net, NETLINK_KOBJECT_UEVENT, &cfg);
> ==>kobject_uevent.c
> 
> 
> I am not sure whether we can reuse the uevent threads for both
> uevents and
> fpin events.
> In case if my understanding is wrong could you please clarify on the
> same.

Right, you can't use the same socket. But you can open two sockets and
listen on both using poll(). That was my idea.

Anyway, this is just an idea. I think for the time being we can move
forward with your current approach, using a separate thread, and
discuss merging the threads later. Please work primarily on my first
reply to your patch with the detailed review.

Martin