Abhijit, On Wed, 2010-06-16 at 11:34 -0700, Abhijit Majumdar wrote: > Hi Philippe > > I have attached a standalone test program which crashes my system. It > uses poxis skin to create a simple task which sleeps for 10 micro sec > and wakes up and continues to do so until the user kills the process. > > Interesting things note -- > > 1. If I uncomment the printf statement at the beginning of the > while loop the program does not crash any more. > 2. OR if I use rt_task_sleep instead of clock_nanosleep it does > not crash.
What happens if you use rt_printf() rather than printf() inside the real-time loop. Some of the examples that I have sent you show the correct usage for this function. > > I am using xenomai 2.5.2 and the arm platform has kernel 2.6.28. I've > cc-ed this email to a tech expert (Travis) of the vendor (EMAC) of the > arm system. > > At the time of crashing I see the following error message on the screen > ---- > > WARNING: at > /home/travis/projects/customers/pivotal_systems/workspace/linux-2.6. > 28-xenomai-pivotal/kernel/sched.c:4382 add_preempt_count+0x84/0x98() > Modules linked in: at91_udc > [<c002e374>] (dump_stack+0x0/0x14) from [<c004510c>] > (warn_on_slowpath+0x4c/0x68 > ) > [<c00450c0>] (warn_on_slowpath+0x0/0x68) from [<c003dd44>] > (add_preempt_count+0x > 84/0x98) > r6:c38dc02c r5:00000000 r4:00000001 > [<c003dcc0>] (add_preempt_count+0x0/0x98) from [<c0045d24>] > (vprintk+0x2c/0x3d4) > [<c0045cf8>] (vprintk+0x0/0x3d4) from [<c00466c8>] (printk+0xe0/0x194) > [<c00465e8>] (printk+0x0/0x194) from [<c00768f0>] > (__xnpod_schedule+0x38c/0x550) > r3:00000003 r2:c039e3a0 r1:c3854000 r0:c032f630 > r8:c480d408 r7:c3b98ca0 r6:c3b98ca0 r5:00000000 r4:c03a0d10 > [<c0076564>] (__xnpod_schedule+0x0/0x550) from [<c007698c>] > (__xnpod_schedule+0x > 428/0x550) > [<c0076564>] (__xnpod_schedule+0x0/0x550) from [<c007698c>] > (__xnpod_schedule+0x > 428/0x550) > [<c0076564>] (__xnpod_schedule+0x0/0x550) from [<c007698c>] > (__xnpod_schedule+0x > 428/0x550) > [<c0076564>] (__xnpod_schedule+0x0/0x550) <1>Unable to handle kernel > paging requ > est at virtual address 00001008 > > > > Thanks for your help > > Abhijit > > > > > > > -----Original Message----- > From: Philippe Gerum [mailto:[email protected]] > Sent: Friday, May 28, 2010 1:05 AM > To: Abhijit Majumdar > Cc: Steve Deiters; [email protected] > Subject: RE: [Xenomai-help] rt_task_sleep causing crashes on PowerPC > > On Wed, 2010-05-26 at 14:03 -0700, Abhijit Majumdar wrote: > > Hi > > > > I get similar problem the xenomai posix skin. I have the latest > version > > of Xenomai (2.5.3) and kernel 2.6.28. > > > > I am using clock_nanosleep(CLOCK_REALTIME, ......) to wait for 1 > > millisecond. It freezes the system. However if I sleep for a second it > > is fine. > > > > Philippe, should your fix work in my case too? > > I have no idea which platform you are running your code on, so my answer > won't be specific, but in short: it is unlikely. This could rather be an > application error. You may want to try the failing code in a small > standalone unit test, and post that code to the list if it still fails > in that context, so we could have a look. > > > If so, can you please > > send the fix. > > > > thanks > > Abhijit > > > > -----Original Message----- > > From: [email protected] > [mailto:[email protected]] > > On Behalf Of Philippe Gerum > > Sent: Sunday, May 16, 2010 2:58 PM > > To: Steve Deiters > > Cc: [email protected] > > Subject: Re: [Xenomai-help] rt_task_sleep causing crashes on PowerPC > > > > On Fri, 2010-05-14 at 19:18 -0500, Steve Deiters wrote: > > > I am running Xenomai 2.5.3, I-pipe version 2.9-00, with Linux > 2.6.33.4 > > > on a PowerPC MPC5121. With small values of sleep ticks passed to > > > rt_task_sleep, I get various sorts of crashes. Here is a simple > > program > > > using a delay loop that exhibits the behavior. > > > > <snip> > > > > > > > > I'm not sure if I have something misconfigured or what. I am > > upgrading > > > from Xenomai 2.4.10 on an older kernel and I did not have this same > > > problem. > > > > > > > Bug confirmed here. Your setup is not involved, I'll send a fix asap. > > > > > Thanks. > > > > > > > > > _______________________________________________ > > > Xenomai-help mailing list > > > [email protected] > > > https://mail.gna.org/listinfo/xenomai-help > > > > > > _______________________________________________ Xenomai-help mailing list [email protected] https://mail.gna.org/listinfo/xenomai-help
