From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4F574E11.7050209@domain.hid> Date: Wed, 07 Mar 2012 13:01:21 +0100 From: Philippe Gerum MIME-Version: 1.0 References: <59395C11A1D1C44ABE7AD0566C50F68BCC15A49EDD@mary.at.omicron.at> In-Reply-To: <59395C11A1D1C44ABE7AD0566C50F68BCC15A49EDD@mary.at.omicron.at> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Xenomai-help] Cast a double value fails List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Bertram Stemer Cc: "'xenomai@xenomai.org'" On 03/07/2012 12:46 PM, Bertram Stemer wrote: > Hi, > I'm using Xenomai 2.5.6 with Linux 2.6.36 on a PowerPC and > have written a real-time application that runs on an isolated > CPU (Kernel option isolcpus). When I start this application on > another core, where a plain Linux application runs I get > sporadically unexpected results in the non real-time application, > when casting a double to an integer?! > > To reproduce this behavior I have a small non real-time test > application that runs in parallel to the RT application: > ... > while (1) { > int z = 4.0; > if (z != 4) > printf("cast error detected!"); > /* sleep some microseconds */ > } > ... > > Does anyone know how this can happen? Is there a CPU utilization > bound for real-time applications that run on the same CPU with > plain Linux tasks? isolcpus does not actually fully isolates CPU from non-rt activity. What you see is likely a bug in the Xenomai core, leaking fpu context bits spuriously between -rt and non-rt. Adding this to the todo list. > > Thanks in advance, > Bertram > > _______________________________________________ > Xenomai-help mailing list > Xenomai-help@domain.hid > https://mail.gna.org/listinfo/xenomai-help > -- Philippe.