Fwd: Querying current tx_queue usage of a SocketCAN interface

[Paarvai Naai <opensource3141@gmail.com>]

Hi,

I have been looking into how to query the SocketCAN interface for its
current tx_queue usage.  I found the following posts touching on this:
http://comments.gmane.org/gmane.network.socketcan.user/1255
http://socket-can.996257.n3.nabble.com/queuesize-manipulation-td310.html

It appears that there is no easy way to find out how much of the
interface's tx_queue has been filled up, but these posts are
relatively old.  Has there been any improved features in this regard
with SocketCAN?

Also, the tx_queue appears to be shared between clients of the
SocketCAN interface.  Even if one process checked the fill state of
the tx_queue, another process could consume the remaining space in the
tx_queue before the first process submits its message for
transmission.  This means that clients have to implement their own TX
queues and use poll() (either in a thread or in the application's main
loop) to occasionally service their private TX queues when the
SocketCAN interface is able to accept new messages.

I saw the following article about using qdisc with SocketCAN but
haven't looked at it in detail yet:
http://rtime.felk.cvut.cz/can/socketcan-qdisc-final.pdf
Has anyone else used qdisc to get around the problem I mention?

Thanks in advance!
Paarvai