From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4CC943A2.9020806@domain.hid> Date: Thu, 28 Oct 2010 11:34:26 +0200 From: Anders Blomdell MIME-Version: 1.0 References: <4CC82C8D.3080808@domain.hid> <4CC84327.9070202@domain.hid> <4CC92786.3030509@domain.hid> <4CC92902.4040904@domain.hid> In-Reply-To: <4CC92902.4040904@domain.hid> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai-core] [RTnet-users] Potential problem with rt_eepro100 List-Id: Xenomai life and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jan Kiszka Cc: rtnet-developers@domain.hid, xenomai@xenomai.org Jan Kiszka wrote: > Am 28.10.2010 09:34, Anders Blomdell wrote: >> Anders Blomdell wrote: >>> Anders Blomdell wrote: >>>> Hi, >>>> >>>> I'm trying to use rt_eepro100, for sending raw ethernet packets, but I'm >>>> experincing occasionally weird behaviour. >>>> >>>> Versions of things: >>>> >>>> linux-2.6.34.5 >>>> xenomai-2.5.5.2 >>>> rtnet-39f7fcf >>>> >>>> The testprogram runs on two computers with "Intel Corporation >>>> 82557/8/9/0/1 Ethernet Pro 100 (rev 08)" controller, where one computer >>>> acts as a mirror sending back packets received from the ethernet (only >>>> those two computers on the network), and the other sends packets and >>>> measures roundtrip time. Most packets comes back in approximately 100 >>>> us, but occasionally the reception times out (once in about 100000 >>>> packets or more), but the packets gets immediately received when >>>> reception is retried, which might indicate a race between rt_dev_recvmsg >>>> and interrupt, but I might miss something obvious. >>> Changing one of the ethernet cards to a "Intel Corporation 82541PI >>> Gigabit Ethernet Controller (rev 05)", while keeping everything else >>> constant, changes behavior somewhat; after receiving a few 100000 >>> packets, reception stops entirely (-EAGAIN is returned), while >>> transmission proceeds as it should (and mirror returns packets). >>> >>> Any suggestions on what to try? >> Since the problem disappears with 'maxcpus=1', I suspect I have a SMP >> issue (machine is a Core2 Quad), so I'll move to xenomai-core. >> (original message can be found at >> http://sourceforge.net/mailarchive/message.php?msg_name=4CC82C8D.3080808%40control.lth.se >> ) >> >> Xenomai-core gurus: which is the corrrect way to debug SMP issues? >> Can I run I-pipe-tracer and expect to be able save at least 150 us of >> traces for all cpus? Any hints/suggestions/insigths are welcome... > > The i-pipe tracer unfortunately only saves traces for a the CPU that > triggered the freeze. To have a full pictures, you may want to try my > ftrace port I posted recently for 2.6.35. 2.6.35.7 ? /Anders