Re: Race condition (was problem) in Mach/Hurd?

[Richard Braun]

On Tue, May 10, 2011 at 10:53:00AM +0200, Svante Signell wrote:
> On Tue, 2011-05-10 at 10:11 +0200, Richard Braun wrote:
> > What makes you think there are two signal threads ?
> 
> Did you look at the pasted output?

Are you serious asking that ?

> I would call threads 5 and 6 signal
> threads and thread 4 the main thrread!? Is there any way to find out??
> Thread 4 is the main thread, I just didn't set the code directory path
> in gdb to see that.
>  
> gdb) thread apply all bt
>  
> Thread 6 (Thread 19821.6):
> #0  0x010f7f4c in mach_msg_trap ()
> at 
> /home/buildd/build/chroot-sid/home/buildd/byhand/eglibc-2.11.2/build-tree/hurd-i386-libc/mach/mach_msg_trap.S:2
> #1  0x010f8749 in __mach_msg (msg=0x29fd4, option=1282, send_size=0, 
>     rcv_size=0, rcv_name=127, timeout=20, notify=0) at msg.c:110
> #2  0x01195608 in timer_thread () at ../sysdeps/mach/hurd/setitimer.c:91
> Cannot access memory at address 0x2a000
> 
> Thread 5 (Thread 19821.5):
> #0  0x010f7f4c in mach_msg_trap ()
> at 
> /home/buildd/build/chroot-sid/home/buildd/byhand/eglibc-2.11.2/build-tree/hurd-i386-libc/mach/mach_msg_trap.S:2
> #1  0x010f8749 in __mach_msg (msg=0x17fef30, option=2, send_size=0, 
>     rcv_size=4096, rcv_name=119, timeout=0, notify=0) at msg.c:110
> #2  0x010f8e04 in __mach_msg_server_timeout (demux=0x1109980
> <msgport_server>, max_size=4096, rcv_name=119, option=0, timeout=0) at
> msgserver.c:101
> #3  0x010f8f4b in __mach_msg_server (demux=0x1109980 <msgport_server>, 
>     max_size=4096, rcv_name=119) at msgserver.c:196
> #4  0x0110994f in _hurd_msgport_receive () at msgportdemux.c:68
> #5  0x01274c3c in entry_point (
>     start_routine=0x11098e0 <_hurd_msgport_receive>, arg=0x0)
> at 
> /home/buildd/build/chroot-sid/home/buildd/byhand/hurd/./libpthread/pthread/pt-create.c:50
> #6  0x00000000 in ?? ()
>  
> Thread 4 (Thread 19821.4):
> #0  0x01113970 in trampoline () from /lib/libc.so.0.3
> #1  0x0000000e in ?? ()
> #2  0x00000000 in ?? ()

I just see threads calling mach_msg() ... One seems to be related to
POSIX timers (timer_thread) and the other is a POSIX thread receiving
a message. I'm not even sure you can see the signal thread with gdb
(I'll check that). So, again, what makes you think there are two signal
threads ?

-- 
Richard Braun