RE: locking timeout error ?

[Badari Pulavarty <pbadari at us dot ibm dot com>]

On Fri, 2006-01-06 at 16:37 -0800, Stone, Joshua I wrote:
> Martin Hunt wrote:
> > On Fri, 2006-01-06 at 15:25 -0800, Badari Pulavarty wrote:
> >> What does this mean ?
> >> 
> >>  # stap  -g topsys.stp
> >> ERROR: locking timeout over variable global_syscalls_count near
> >> identifier 'syscalls_count' at topsys.stp:27:2
> > 
> > You've found a bug.
> > 
> > If you are saving stats in a map, then trying to print them, you have
> > probably hit http://sourceware.org/bugzilla/show_bug.cgi?id=2056
> > 
> > Otherwise, can you post some source which shows what you are doing?
> > 
> > Martin
> 
> This is in CVS: tests/testsuite/systemtap.samples/topsys.stp
> 
> In fact the problem here is that the script is *not* using stats - it's
> incrementing a counter in a global array.  So Badari must be running on
> an SMP machine, and two threads are trying to access the array at the
> same time.
> 
> A few days ago Frank checked in code to let it wait longer to attain a
> lock, so you might have better luck with a newer CVS build.
> 
> I would suggest that we should convert that script to use stats, but as
> Martin points out, it's also buggy right now.

Yes. Latest version seems to be working fine. (Of course, I had to use
Hien's patch for get_user_asm() to make it compile).

Thanks,
Badari