Re: Understading of User trace output

* Srinivasa Reddy ([email protected]) wrote:
> Hi Matieu,
> 
> I have gone through the ReadMe file done everything as per that only.
> Everything is working fine and I am getting the user trace output as per
> that ReadMe only.
> 
> But I am getting some confusion while interpreting the output messages
> of the user trace.
> 
> In my application the sample.c file contains the following function:
> 
> trace_user_generic_string("Hello world! Have a nice day.");
> 
> I have compiled and executed that application. And got the trace
> information also.
> 
> When I execute the lttv -m textDump...... command, it's giving the
> following output.
> 
> user_generic.string: 42962540.300034178
> (/home/rrao/NFS/NFS_test/home/sreddy/usrtrace3/cpu_0), 327, 327,
> ./sample-tata, UNBRANDED, 268, 0x0, SYSCALL { "Hello world! Have a nice
> day." }
> 
> 
> From that above message I understood only that 
> 
> SYSCALL { "Hello world! Have a nice day." }  message, because it's there
> in that trace_user_generic_string function call.
> 
> But I didn't understand the remaining numbers in that output message.
> 
> What does meant by :
> 
> 42962540.300034178,
> (/home/rrao/NFS/NFS_test/home/sreddy/usrtrace3/cpu_0), 327, 327,
> ./sample-tata, UNBRANDED, 268, 0x0,
> 
> Could you please explain me what is that each parameter and what
> information we can get from them??
> 
> Or suggest me any document to get these information details...
> 

I'm afraid that the best doc for this one is LTTV source code (here:
lttv/lttv/print.c). Luckily, in this post, I already gave a legend of
the output:

http://www.mail-archive.com/[email protected]/msg183011.html

Quoting:

group.event          : time since boot, in s.ns (tracefile name, ending
with cpu ID), Thread ID ("pid"), Thread group ID (posix pid), process
name, thread name (need userspace instrumentation), Parent PID,
Userspace function (need userspace instrumentation), execution mode
(SYSCALL/USERMODE/TRAP/IRQ...) { event specific data }

Mathieu


> Regards,
> Srinivas.
> 
> -----Original Message-----
> From: Mathieu Desnoyers [mailto:[email protected]] 
> Sent: Friday, August 10, 2007 1:04 AM
> To: Srinivasa Reddy
> Cc: [email protected]
> Subject: Re: Understading of User trace output
> 
> * Srinivasa Reddy ([email protected]) wrote:
> > Hi Mathieu,
> > 
> > I am working on user trace. I am able to execute all the commands as
> per
> > the Readme and everything is working fine.
> > 
> > I am getting the following output when I execute the lttv -m
> > textDump...... command.
> > 
> > But I am not able to understand what does it mean?
> > 
> > Could you please explain me how can we use the usetrace?
> > 
> 
> The c files in the usertrace package are examples. sample-printf.c is
> less than 10 lines and looks a lot like a normal printf, but outputs the
> data in the trace buffers. Each of these lines are an event from your
> trace, just like standard kernel events, but they come from userspace.
> 
> By using this, you can correlate user-space events with kernel events in
> a trace.
> 
> More elaborated features are explained in the readme.
> 
> Mathieu
> > 
> > user_generic.string: 42962540.300034178
> > (/home/rrao/NFS/NFS_test/home/sreddy/usrtrace3/cpu_0), 327, 327,
> > ./sample-tata, UNBRANDED, 268, 0x0, SYSCALL { "Hello world! Have a
> nice
> > day." }
> > 
> > user_generic.slow_printf: 42962540.350030516
> > (/home/rrao/NFS/NFS_test/home/sreddy/usrtrace3/cpu_0), 327, 327,
> > ./sample-tata, UNBRANDED, 268, 0x0, SYSCALL { "in: sample-tata.c at:
> > main:24: Counter value is: 0." }
> > 
> > user_generic.string: 42962541.370010985
> > (/home/rrao/NFS/NFS_test/home/sreddy/usrtrace3/cpu_0), 327, 327,
> > ./sample-tata, UNBRANDED, 268, 0x0, SYSCALL { "Hello world! Have a
> nice
> > day." }
> > 
> > user_generic.slow_printf: 42962541.370014647
> > (/home/rrao/NFS/NFS_test/home/sreddy/usrtrace3/cpu_0), 327, 327,
> > ./sample-tata, UNBRANDED, 268, 0x0, SYSCALL { "in: sample-tata.c at:
> > main:24: Counter value is: 1." }
> > 
> > user_generic.string: 42962542.380010985
> > (/home/rrao/NFS/NFS_test/home/sreddy/usrtrace3/cpu_0), 327, 327,
> > ./sample-tata, UNBRANDED, 268, 0x0, SYSCALL { "Hello world! Have a
> nice
> > day." }
> > 
> > user_generic.slow_printf: 42962542.380014647
> > (/home/rrao/NFS/NFS_test/home/sreddy/usrtrace3/cpu_0), 327, 327,
> > ./sample-tata, UNBRANDED, 268, 0x0, SYSCALL { "in: sample-tata.c at:
> > main:24: Counter value is: 2." }
> > 
> > Regards,
> > Srinivas.
> > 
> 
> -- 
> Mathieu Desnoyers
> Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal
> OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F  BA06 3F25 A8FE 3BAE
> 9A68
> 

-- 
Mathieu Desnoyers
Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F  BA06 3F25 A8FE 3BAE 9A68