probing the "label" is not working correctly

Srinivasa D S srinivasa@in.ibm.com
Fri May 26 06:48:00 GMT 2006


Hi
  I have installed systemtap on FC5 machine(i386 platform). I am able to 
write scripts and execute them. I found one problem when probing labels 
in kernel  function.
  "copy_process"  has "fork_out" label and I write script like below it 
works
   
   probe kernel.statement(0xc0118846).label("fork_out")
    {
    printf("iam here %s %d\n",execname(),pid());
    }
  
   [root@localhost probedef]# cat /proc/kallsyms | grep c0118846
    c0118846 t copy_process
   ===================================================
   but if I change the address in  to "copy_process", I am getting this 
error

    probe kernel.statement("copy_process").label("fork_out")
    {
    printf("iam here %s %d\n",execname(),pid());
    }

   [root@localhost probedef]# stap -vvvv label.stp
Created temporary directory "/tmp/stapGHPUp4"
Searched 
'/usr/local/share/systemtap/tapset/2.6.15-1.2054_FC5/i686/*.stp', match 
count 0
Searched '/usr/local/share/systemtap/tapset/2.6.15-1.2054_FC5/*.stp', 
match count 0
Searched '/usr/local/share/systemtap/tapset/2.6.15/i686/*.stp', match 
count 0
Searched '/usr/local/share/systemtap/tapset/2.6.15/*.stp', match count 0
Searched '/usr/local/share/systemtap/tapset/2.6/i686/*.stp', match count 0
Searched '/usr/local/share/systemtap/tapset/2.6/*.stp', match count 0
Searched '/usr/local/share/systemtap/tapset/i686/*.stp', match count 1
Searched '/usr/local/share/systemtap/tapset/*.stp', match count 16
Pass 1: parsed user script and 17 library script(s) in 
100usr/0sys/138real ms.
parsed 'copy_process' -> func 'copy_process'
pattern 'kernel' matches module 'kernel'
focused on module 'kernel' = [c0100000-c042f25c, bias 0]
semantic error: incomplete: do not know how to interpret .label: 
identifier 'probe' at label.stp:6:2
pattern 'kernel' matches module 'kernel'
semantic error: no match for probe point
while: resolving probe point 
kernel.statement("copy_process").label("fork_out")
Pass 2: analyzed script: 0 probe(s), 0 function(s), 0 global(s) in 
190usr/30sys/243real ms.
Pass 2: analysis failed.  Try again with more '-v' (verbose) options.
Running rm -rf /tmp/stapGHPUp4
==============================================================

 Shouldn't we use function name while probing label?
 Please comment

Thanks
  Srinivasa DS



More information about the Systemtap mailing list