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View Full Version : Red Zone debugging always waits for mutex



eric.zuur
11-05-2009, 07:23 AM
Dear,

I've been trying to debug my program using the Red Zones functionality in MemoryScape. Unfortunatelly, I haven't seen it work yet. At first I thought that debugging with Red Zones takes a long time, but after halting the application, it seems that it is waiting for a mutex.
This is the stack trace:

__kernel_vsyscall, FP=ffffc910
__lll_mutex_lock_wait, FP=ffffc938
_L_mutex_lock_35, FP=ffffc938
TV_pthread_mutex_lock, FP=ffffc948
lock_rz_table, FP=ffffc958
do_allocation, FP=ffffc9e8
TV_HEAP_rz_allocator_malloc, FP=ffffca38
malloc_body, FP=ffffcaf8
TV_HEAP_malloc_interposer, FP=ffffcb88
malloc, FP=ffffcba8
.....

It seems that the debugger is not going any further. How can I solve this problem?

Regards,

Eric.

PeterT-RogueWave
11-09-2009, 02:43 PM
Hello Eric,

Darn.

Can you tell me which version of TotalView you are using? We have seen problems with programs that use dlopen calls and the dlopen does a malloc and get get into a mutex deadlock much as you report. I haven't actually seen this with RedZone just yet, but I imagine that the opportunity to get into this deadlock also exists there. The reason I ask about the version of TV is that we had an earlier report of this with memory debugging, and thought we had resolved that in 8.7.0-3. However, while reducing the frequency of the mutex lock, it does not appear to be entirely solved. So we're still looking into that.

However, if this turns out to be specific to RedZone's then it may be this is a new issue we need to look into. If you have 8.7.0-3 or 8.7.0-4, then you are either running into the known issue, or have come up with a new one. If so, we would certainly be interested in resolving it, should you have a reproducer you can send to

support@totalviewtech.com

If that is not feasible, I can try to remember to post back in here when we have a more complete resolution for the known problem, and we can see if it helps in your case as well.

Make sense?

Regards,

eric.zuur
11-10-2009, 01:09 AM
Peter,

I'm using Totalview 8.7.0-4 (the latest).
At this moment, I don't have a reproducer program.
If I find this problem in a smaller example program, I will tell you.

Do you want me to report this issue with support?

Regards,

Eric.

PeterT-RogueWave
11-10-2009, 07:57 AM
Hi Eric,

Sure. Send it to support with as much info as you can. I assume when you say you don't have a reproducer that you don't have a reproducer you can give us? Or is it that the problem has gone away for the moment? (I hope, but have no great faith in...)

Regards,

eric.zuur
11-10-2009, 08:00 AM
Peter,

That's a correct assumption.
I can reproduce it, but I can't give it to you.
I will prepair a mail to support tommorow morning (Dutch Time) and hopefully you can pinpoint and solve the problem soon.

Regards,

Eric.