<div dir="ltr">Hi Sisu,<div><br></div><div>You need to give the full path to the device and not just the name. Example: 'sudo ftcat /dev/litmus/ft_trace0 SCHED RELEASE'. See 'ls /dev/litmus' for all the tracing devices. There is one sched_trace device per CPU, and one ft_trace device shared amongst all CPUs.</div>
<div class="gmail_extra"><br><br><div class="gmail_quote">On Wed, Apr 17, 2013 at 12:24 PM, Sisu Xi <span dir="ltr"><<a href="mailto:xisisu@gmail.com" target="_blank">xisisu@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">
<div dir="ltr"><div><div><div>Hi, litmus developers:<br><br>sorry to bother you again. I recompile the kernel and still get this message.<br><br>xisisu@litmus1:~/ft_tools$ sudo ftcat ft_trace SCHED_START SCHED_END > ../temp.out <br>
<div>
Error: could not open feathertrace device (ft_trace): No such file or directory<br>Usage: ftcat [OPTIONS] <ft device> TS1 TS2 ....<br><br>Options:<br> -s SIZE -- stop tracing afer recording SIZE bytes<br><br><br>
</div></div>However, I was able to get the log file working<br>xisisu@litmus1:~/ft_tools$ sudo cat /dev/litmus/log > ../temp.out <br>^Cxisisu@litmus1:~/ft_tools$ head ../temp.out <br>50368 P0: check_for_preemptions: attempting to link task 1081 to 3<br>
50369 P0: P0 is closest available CPU to P0<br>50370 P0: (swapper/0:0) will be preempted by base_task/1081<br>50371 P0: (base_task/1081:4579) scheduled_on = P0<br>50372 P0: (base_task/1081:4579) arming enforcement timer.<br>
50373 P0: gsnedf_scheduler_tick: 1081 is preemptable => FORCE_RESCHED<br>50374 P0: enforcement timer fired.<br>50375 P0: (base_task/1081:4579) blocks:0 out_of_time:1 np:0 sleep:0 preempt:0 state:0 sig:0<br>50376 P0: (base_task/1081:4579) job_completion().<br>
<br><br><br></div>This is my config file<br><br>xisisu@litmus1:~/litmus-rt$ tail .config<br># Tracing<br>#<br>CONFIG_FEATHER_TRACE=y<br>CONFIG_SCHED_TASK_TRACE=y<br>CONFIG_SCHED_TASK_TRACE_SHIFT=9<br>CONFIG_SCHED_LITMUS_TRACEPOINT=y<br>
CONFIG_SCHED_OVERHEAD_TRACE=y<br>CONFIG_SCHED_DEBUG_TRACE=y<br>CONFIG_SCHED_DEBUG_TRACE_SHIFT=18<br># CONFIG_SCHED_DEBUG_TRACE_CALLER is not set<br><br><br></div>any hint about this?<br><br>Thanks very much!<span><font color="#888888"><br>
<br>Sisu<br>
<div><div><br><br><div><br><div><br><br><br><br><br><br></div></div></div></div></font></span></div><div><div><div class="gmail_extra"><br><br><div class="gmail_quote">On Tue, Apr 16, 2013 at 2:58 PM, Sisu Xi <span dir="ltr"><<a href="mailto:xisisu@gmail.com" target="_blank">xisisu@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><div dir="ltr">I just checked my<div># CONFIG_SCHED_OVERHEAD_TRACE is not set<br>
</div><div>is not set..</div><div><br>
</div><div>I'll recompile the kernel with this enabled.</div><div><br></div>
<div>thanks all the same.</div><span><font color="#888888"><div><br></div><div>sisu</div></font></span></div><div><div><div class="gmail_extra"><br><br><div class="gmail_quote">On Tue, Apr 16, 2013 at 2:22 PM, Sisu Xi <span dir="ltr"><<a href="mailto:xisisu@gmail.com" target="_blank">xisisu@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex"><div dir="ltr">Hi, all:<div><br></div><div>I installed the litmus-rt within a guest VM using Xen hypervisor. I can run base_task without problem, and also I can check the /dev/litmus/log files. However, when I try to use the ft_tools, it gives the following errors. Does anyone know why?</div>
<div><br></div><div><span style="font-family:arial,sans-serif;font-size:13px">xisisu@litmus1:~/ft_tools$ sudo ./st_trace global-exp</span><br style="font-family:arial,sans-serif;font-size:13px"><span style="font-family:arial,sans-serif;font-size:13px">CPU 0: 1081 > st-global-exp-0.bin [0]</span><br style="font-family:arial,sans-serif;font-size:13px">
<span style="font-family:arial,sans-serif;font-size:13px">Press Enter to end tracing...</span><br style="font-family:arial,sans-serif;font-size:13px"><br style="font-family:arial,sans-serif;font-size:13px"><span style="font-family:arial,sans-serif;font-size:13px">Ending Trace...</span><br style="font-family:arial,sans-serif;font-size:13px">
<span style="font-family:arial,sans-serif;font-size:13px">Disabling 10 events.</span><br style="font-family:arial,sans-serif;font-size:13px"><span style="font-family:arial,sans-serif;font-size:13px">[ 259.507087] Failed trace writes: 0</span><br style="font-family:arial,sans-serif;font-size:13px">
<span style="font-family:arial,sans-serif;font-size:13px">/dev/litmus/sched_trace0: 10176 bytes read.</span><br style="font-family:arial,sans-serif;font-size:13px"><span style="font-family:arial,sans-serif;font-size:13px">xisisu@litmus1:~/ft_tools$ cat /dev/litmus/sched_trace0 </span><br style="font-family:arial,sans-serif;font-size:13px">
<span style="font-family:arial,sans-serif;font-size:13px">cat: /dev/litmus/sched_trace0: Permission denied</span><br style="font-family:arial,sans-serif;font-size:13px"><span style="font-family:arial,sans-serif;font-size:13px">xisisu@litmus1:~/ft_tools$ sudo cat /dev/litmus/sched_trace0 </span><br style="font-family:arial,sans-serif;font-size:13px">
<span style="font-family:arial,sans-serif;font-size:13px">[ 278.522061] Failed trace writes: 0</span><br style="font-family:arial,sans-serif;font-size:13px"><br><span style="font-family:arial,sans-serif;font-size:13px">xisisu@litmus1:~/ft_tools$ sudo ./ftcat ft_trace CXS_START CXS_END > ../temp.out </span><br style="font-family:arial,sans-serif;font-size:13px">
<span style="font-family:arial,sans-serif;font-size:13px">Error: could not open feathertrace device (ft_trace): No such file or directory</span><br style="font-family:arial,sans-serif;font-size:13px"><span style="font-family:arial,sans-serif;font-size:13px">Usage: ftcat [OPTIONS] <ft device> TS1 TS2 ....</span><br style="font-family:arial,sans-serif;font-size:13px">
<br style="font-family:arial,sans-serif;font-size:13px"><span style="font-family:arial,sans-serif;font-size:13px">Options:</span><br style="font-family:arial,sans-serif;font-size:13px"><span style="font-family:arial,sans-serif;font-size:13px"> -s SIZE -- stop tracing afer recording SIZE bytes</span></div>
<div><font face="arial, sans-serif"><br></font></div><div><font face="arial, sans-serif"><br></font></div><div><font face="arial, sans-serif"><br></font></div><div><font face="arial, sans-serif"><br></font></div><div><font face="arial, sans-serif"><br>
</font></div><div><font face="arial, sans-serif"> I am running it on a intel i7 machine, with hyperthreading disabled. Kernel is configured following the instruction on your website. Seems litmus is compatible with the xen guest patch. My host runs a normal linux kernel, 3.4.35 on CentOS 6.3, and my guest VM is Ubuntu 12.04, para-virtualized.</font></div>
<div><font face="arial, sans-serif"><br></font></div><div><font face="arial, sans-serif">Thanks very much!</font></div><span><font color="#888888"><div><font face="arial, sans-serif"><br></font></div><div>
<font face="arial, sans-serif">Sisu</font></div>
<div><font face="arial, sans-serif"><br></font></div><div><font face="arial, sans-serif"><br></font></div><div><font face="arial, sans-serif"><br></font></div><div><font face="arial, sans-serif"><br></font></div><div><font face="arial, sans-serif"><br>
</font></div><div><font face="arial, sans-serif"><br></font></div><div><font face="arial, sans-serif"><br></font></div><div><font face="arial, sans-serif"><br clear="all"></font><div><br></div>-- <br>Sisu Xi, PhD Candidate<br>
<br><a href="http://www.cse.wustl.edu/~xis/" target="_blank">http://www.cse.wustl.edu/~xis/</a><br>Department of Computer Science and Engineering<br>Campus Box 1045<br>Washington University in St. Louis<br>One Brookings Drive<br>
St. Louis, MO 63130
</div></font></span></div>
</blockquote></div><br><br clear="all"><div><br></div>-- <br>Sisu Xi, PhD Candidate<br><br><a href="http://www.cse.wustl.edu/~xis/" target="_blank">http://www.cse.wustl.edu/~xis/</a><br>Department of Computer Science and Engineering<br>
Campus Box 1045<br>Washington University in St. Louis<br>One Brookings Drive<br>St. Louis, MO 63130
</div>
</div></div></blockquote></div><br><br clear="all"><br>-- <br>Sisu Xi, PhD Candidate<br><br><a href="http://www.cse.wustl.edu/~xis/" target="_blank">http://www.cse.wustl.edu/~xis/</a><br>Department of Computer Science and Engineering<br>
Campus Box 1045<br>Washington University in St. Louis<br>One Brookings Drive<br>St. Louis, MO 63130
</div>
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<br></blockquote></div><br><br clear="all"><div><br></div>-- <br>Jonathan Herman<br>Department of Computer Science at UNC Chapel Hill
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