From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Wed, 06 Aug 2008 12:30:53 +0200 Message-Id: <1251450790@domain.hid> MIME-Version: 1.0 From: Jochen Behnke Content-Type: text/plain; charset=iso-8859-15 Content-Transfer-Encoding: 7bit Subject: [Xenomai-help] unwanted switch to secondary mode on call to rt_dev_ioctl List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: xenomai@xenomai.org Hello, my xenomai application performs unwanted mode switches to secondary mode. To find out which function is causing the mode switch I activated the T_WARNSW bit for the xenomai task involved. I figured out that a call to rt_dev_ioctl is the cause. Then I found out that the responsible rtdm driver does only register an ioctl_nrt handler leaving the ioctl_rt handler set to NULL. It seemed logical to me, that calling a nonrt driver function from a xenomai task in primary mode would cause a switch to secondary mode. So I modified the rtdm driver to register the ioctl handler for both ioctl_nrt and ioctl_rt. Unfortunately this did not solve the problem. As a next step I reduced the ioctl handler to a "return 0" statement, to be sure that no function calls inside the ioctl handler could generate a switch to secondary mode. Again this did not improve the situation. It even seems as if the driver's ioctl handler is not called at all. For the most recent test I wrote a smaller xenomai application that does cyclic rt_dev_ioctl calls on the same rtdm driver from within a seperate xenomai task. The application runs without problems, the rt task does not perform any unwanted switches to secondary mode thus not receiving any SIGXCPU signals. My configuration Processor Celeron 400Hz xenomai 2.4.2 Kernel 2.6.24 I have no idea what is going wrong, any hint is appreciated. Thanks. Jochen _________________________________________________________________________ In 5 Schritten zur eigenen Homepage. Jetzt Domain sichern und gestalten! Nur 3,99 EUR/Monat! http://www.maildomain.web.de/?mc=021114