[ltt-dev] problems with ust

[Pierre-Marc Fournier]

Bonjour,

Sylvain Geneves wrote:
> Hi all,
> 
> I've pulled UST from git yesterday, and noticed some errors, and some
> are confusing me...
> 
> first of all, i have a problem for compiling my program (when i include
> marker.h), it gives the following error :
> 
> In file included from /usr/local/include/ust/kcompat/kcompat.h:64,
>                  from /usr/local/include/ust/kernelcompat.h:21,
>                  from /usr/local/include/ust/marker.h:31,
>                  from task.lbc.C:4:
> /usr/local/include/ust/kcompat/jhash.h: In function ‘u32 jhash(const
> void*, u32, u32)’:
> /usr/local/include/ust/kcompat/jhash.h:47: error: invalid conversion
> from ‘const void*’ to ‘const u8*’

Will look into this.

> 
> 
> seems like it lacks a cast somewhere, which i added. After that it
> compiles fine, and there goes another problem :
> 
> when i run :
> usttrace -l ./myprog
> 
> i've got the following output (with debug flags enabled):
> http://pastebin.com/raw.php?i=4uCgJDM6
> 
> myprog is calling clone via pthread_create. I have instrumented it with
> a line like this, which is executed many times (almost 4 million calls):
>   trace_mark(main, myevent, "calling cb" );

You also seem to have fork()s somewhere because there are directories
with several different PIDs in your trace directory. Therefore you need
to add the -f option to usttrace.

> 
> Here's what i see in the resulting trace directory:
> 
> http://pastebin.com/raw.php?i=TqJWarkA
> 
> it seems that all traces aren't recorded (some metadata and ust are zero
> size), i can't understand why, i must be missing something here... ?

-f should fix this.

> 
> also, when using lttv, it says "Cannot open trace : maybe you should
> enter in the trace directory to select it ?"
> i note that lttv can open a subdirectory (like
> /root/.usttraces/californium-20100329172748911948191/8494_5454077942969735172
> in my example), but obviously all i can see is a subset of what really
> happenned...

This is a consequence of some files having 0 size.

> 
> i would really appreciate if you could show me what i'm doing wrong.
> 
> 
> Regards,
> Sylvain
> 
> PS: i use userspace-rcu-0.4.3 and the git version of ust and lttv
> 
> 
> 
> ------------------------------------------------------------------------
> 
> _______________________________________________
> ltt-dev mailing list
> ltt-dev at lists.casi.polymtl.ca
> http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev