From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oliver Hartkopp Subject: Re: Retrieve amount of queued frames in the txqueue of a interface Date: Thu, 07 Feb 2013 18:43:51 +0100 Message-ID: <5113E7D7.4070807@hartkopp.net> References: <5113851F.1060501@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mo-p00-ob.rzone.de ([81.169.146.161]:13940 "EHLO mo-p00-ob.rzone.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759194Ab3BGRny (ORCPT ); Thu, 7 Feb 2013 12:43:54 -0500 In-Reply-To: Sender: linux-can-owner@vger.kernel.org List-ID: To: Felix Obenhuber Cc: Marc Kleine-Budde , linux-can@vger.kernel.org On 07.02.2013 17:18, Felix Obenhuber wrote: > Hi Marc, > > On Thu, Feb 7, 2013 at 11:42 AM, Marc Kleine-Budde wrote: >> On 02/06/2013 12:59 PM, Felix Obenhuber wrote: >>> Hi, >>> >>> how can I retrive the number of frames currently queued for >>> transmission on a SocketCAN interface? Is this possible via netlink? >> >> Sorry, I don't know. What's you usecase? > > We're working with ISOBUS systems (ISO11783). During a transport > protocol session (similiar to iso tp) we'd like to know how many > frames can get queued at once to adjust timings. There are multiple > software modules that might send frames at the same time over a > single module/socket. > > Maybe we have to add a tx fifo within the software... Probably the Linux queueing disciplines for CAN are interesting for you: http://rtime.felk.cvut.cz/can/socketcan-qdisc-final.pdf The funtionality is part of the Linux Kernel since 3.6. Regards, Oliver