From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wolfgang Grandegger Subject: Re: [PATCH v6] can: sja1000: fix {pre,post}_irq() handling and IRQ handler return value Date: Thu, 05 Dec 2013 21:26:45 +0100 Message-ID: <52A0E185.1080402@grandegger.com> References: <1385334220-31887-1-git-send-email-mkl@pengutronix.de> <52A0BCD9.4090309@grandegger.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from ngcobalt02.manitu.net ([217.11.48.102]:50785 "EHLO ngcobalt02.manitu.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751584Ab3LEU0r (ORCPT ); Thu, 5 Dec 2013 15:26:47 -0500 In-Reply-To: Sender: linux-can-owner@vger.kernel.org List-ID: To: Richard Andrysek , linux-can@vger.kernel.org On 12/05/2013 08:37 PM, Richard Andrysek wrote: > Wolfgang Grandegger grandegger.com> writes: > >> 2) How the data overrun can happen, if the can bus load is ~25%? >> >> If a bunch of messages is sent in a short time. The 25% is an average >> load, I assume. >> >>> >>> $ sudo cat /proc/net/can/stats >>> [sudo] password for ran: >>> >>> 1421819 transmitted frames (TXF) >>> 2606493 received frames (RXF) >>> 473873 matched frames (RXMF) >>> >>> 18 % total match ratio (RXMR) >>> 2400 frames/s total tx rate (TXR) >>> 4400 frames/s total rx rate (RXR) >>> >>> 18 % current match ratio (CRXMR) >>> 2400 frames/s current tx rate (CTXR) >>> 4400 frames/s current rx rate (CRXR) >>> >>> 18 % max match ratio (MRXMR) >>> 2427 frames/s max tx rate (MTXR) >>> 4427 frames/s max rx rate (MRXR) >>> >>> 4 current receive list entries (CRCV) >>> 9 maximum receive list entries (MRCV) >>> >>> 2 statistic resets (STR) >> >> # ip -d -s link show can0 >> >> will list the CAN statistics. >> >> Wolfgang. >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-can" in >> the body of a message to majordomo vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> >> > > Hi Wolfgang, > > thank you for help. I've recognized that these two lines comes from a > network world: > > RX packets:12462166 errors:121380 dropped:0 overruns:0 frame:121380 > TX packets:11604619 errors:678 dropped:0 overruns:0 carrier:0 What do you mean? CAN belongs to the network world. What does the following command report: # ip -d -s link show can0 > Then each event "arbitration lost" generates an IRQ. >From a CAN device? > Is it OK to disable it, just now for tests. With that I want to reduce an > amount of IRQs. Is it possible to disable it without a new compilation of a > kernel? "ifconfig down" should do the job. You may get in trouble if it's your ethernet device, though. > We are running quite fast, in few ms. So we test your driver quite well:) With "-rt" or with vanilla Linux? Wolfgang.