command line ...
root@smurf:/home/ls/src/emc/emc2-dev/src/hal# chrt 99 ./shm_interface_test
Error while shmget
Semaphore value is 0
Waiting one second, then until semaphore gets released
Segmenteringsfel
dmesg ...
[ 3579.723705] shm_interface_t[2462]: segfault at ffffffffa76ad000 ip
0000000000400d14 sp 00007fff128c4600 error 6 in
shm_interface_test[400000+2000]
I tried running with gdb but didn't get anything interesting, and it's
not a lot.
I tried strace also
arch_prctl(ARCH_SET_FS, 0x7fcf1a3d9700) = 0
mprotect(0x7fcf19b98000, 16384, PROT_READ) = 0
mprotect(0x7fcf19da8000, 4096, PROT_READ) = 0
mprotect(0x7fcf19fc0000, 4096, PROT_READ) = 0
mprotect(0x7fcf1a3f8000, 4096, PROT_READ) = 0
munmap(0x7fcf1a3dc000, 103274) = 0
set_tid_address(0x7fcf1a3d99d0) = 2483
set_robust_list(0x7fcf1a3d99e0, 0x18) = 0
futex(0x7fffd6bb89fc, FUTEX_WAKE_PRIVATE, 1) = 0
futex(0x7fffd6bb89fc, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME,
1, NULL, 7fcf1a3d9700) = -1 EAGAIN (Resource temporarily unavailable)
rt_sigaction(SIGRTMIN, {0x7fcf19daf860, [], SA_RESTORER|SA_SIGINFO,
0x7fcf19db8f60}, NULL, 8) = 0
rt_sigaction(SIGRT_1, {0x7fcf19daf8f0, [],
SA_RESTORER|SA_RESTART|SA_SIGINFO, 0x7fcf19db8f60}, NULL, 8) = 0
rt_sigprocmask(SIG_UNBLOCK, [RTMIN RT_1], NULL, 8) = 0
getrlimit(RLIMIT_STACK, {rlim_cur=8192*1024, rlim_max=RLIM_INFINITY}) = 0
shmget(0xcafe, 88, 0666) = 2883607
shmat(2883607, 0, 0) = ?
statfs("/dev/shm", {f_type=0x1021994, f_bsize=4096, f_blocks=127182,
f_bfree=127181, f_bavail=127181, f_files=127182, f_ffree=127179,
f_fsid={0, 0}, f_namelen=255, f_frsize=4096}) = 0
futex(0x7fcf19fc52bc, FUTEX_WAKE_PRIVATE, 2147483647) = 0
open("/dev/shm/sem.emcsem1", O_RDWR|O_NOFOLLOW) = 3
fstat(3, {st_mode=S_IFREG|0755, st_size=32, ...}) = 0
brk(0) = 0xc9f000
brk(0xcc0000) = 0xcc0000
mmap(NULL, 32, PROT_READ|PROT_WRITE, MAP_SHARED, 3, 0) = 0x7fcf1a3f4000
close(3) = 0
fstat(1, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 1), ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1,
0) = 0x7fcf1a3f3000
write(1, "Semaphore value is 0\n", 21Semaphore value is 0
) = 21
write(1, "Waiting one second, then until s"..., 55Waiting one second,
then until semaphore gets released
) = 55
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
rt_sigaction(SIGCHLD, NULL, {SIG_DFL, [], 0}, 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
nanosleep({1, 0}, 0x7fffd6bb8860) = 0
--- SIGSEGV (Segmentation fault) @ 0 (0) ---
+++ killed by SIGSEGV +++
Segmenteringsfel
And a small guess ... I'm running 64 bit ? ...
I have not had time to look to much at the code, since I have been ill
this week, but It seems to run.
I have mostly been busy trying to get an USB driver running for my
hardware, sorry but limited time.
I do believe that shm_interface_test ran a couple of times ....
Tell me if I can run any test, but at the moment I am actually more
concearned about RT-Preempt EMC :-D ... which is a reason to be really
happy.
Have you tried the mailinglist for rt-preempt about the timing ? it's
on http://osadl.org/ , or lkml.org ... I knot the hpet timers have
undergone some work.
/ regards, Lars Segerlund.
2011/6/19 Michael Abel <michael.a...@isw.uni-stuttgart.de>:
>
> Hi Lars,
>
> I walked a bit trough the code and tried some things out. There is already
> cleanup code to avoid this problem, but the cleanup works only when emc is
> started as root. It seems just like a problem with permissions. I recommend
> to start emc as root to avoid the problems.
>
> In case of problems it's also possible to remove the shm by hand with these
> commands:
>
> ipcrm -M 0x48414c32 #(hal shm)
> ipcrm -M 0x0000cafe #(shm interface)
>
> Can you please tell me more about the segfaulting shm_tester? I have no
> problems with this program here...
> Thanks!
>
> regards Michael
>
> "Lars Segerlund" <lars.segerl...@gmail.com> schrieb:
>> I am seing the same thing, after running emc & your shm_tester a
>> couple of times, ipcs gets some cruft, and I can not start emc again
>> ... shm_tester segfaults ....
>>
>> Trying to investigate ....
>>
>> / regards Lars Segerlund
>>
>> 2011/6/18 Michael Abel <michael.a...@isw.uni-stuttgart.de>:
>>>
>>> Hello Guys,
>>>
>>> I probably found the problem, why you sometimes have to call halcmd as
>>> root to get emc started again. But I don't have a bugfix up to now.
>>>
>>> It seems like the complete hal shared memory is not given back to the os
>>> when emc is closed and my shm_tester is still running. For that reason
> you
>>> can still access the memory when emc has quit. When halcmd is started
>>> from the root account, the memory is also still there, but its possible
>>> to start emc again.
>>>
>>> This is printed after emc has quit:
>>>
>>> $ halcmd -V status
>>> HAL: initializing component 'halcmd26165'
>>> HAL: component 'halcmd26165' initialized, ID = 26165
>>> HAL locking status:
>>> current lock value 0 (00)
>>> HAL_LOCK_NONE - nothing is locked
>>> HAL memory status
>>> used/total shared memory: 48238/262000
>>> active/recycled components: 1/12
>>> active/recycled pins: 0/417
>>> active/recycled parameters: 0/65
>>> active/recycled aliases: 0/0
>>> active/recycled signals: 36/0
>>> active/recycled functions: 0/17
>>> active/recycled threads: 1/0
>>> HAL: removing component 26165
>>> HAL: component 26165 removed, name = 'halcmd26165'
>>>
>>>
>>> One can also see that there is shared memory left with ipcs:
>>>
>>> ipcs -m -p | grep <old_pid_of_rtapi_app>
>>>
>>> Does somebody know, how the rtai version of emc is handling hal shared
>>> memory? Is it still there after closing emc?
>>>
>>> Greetings,
>>> Michael
>>>
>>>
>>>
>>>
>>>
> ------------------------------------------------------------------------------
>>> EditLive Enterprise is the world's most technically advanced content
>>> authoring tool. Experience the power of Track Changes, Inline Image
>>> Editing and ensure content is compliant with Accessibility Checking.
>>> http://p.sf.net/sfu/ephox-dev2dev
>>> _______________________________________________
>>> Emc-developers mailing list
>>> Emc-developers@lists.sourceforge.net
>>> https://lists.sourceforge.net/lists/listinfo/emc-developers
>>>
>>
>>
> ------------------------------------------------------------------------------
>> EditLive Enterprise is the world's most technically advanced content
>> authoring tool. Experience the power of Track Changes, Inline Image
>> Editing and ensure content is compliant with Accessibility Checking.
>> http://p.sf.net/sfu/ephox-dev2dev
>> _______________________________________________
>> Emc-developers mailing list
>> Emc-developers@lists.sourceforge.net
>> https://lists.sourceforge.net/lists/listinfo/emc-developers
>>
>
>
>
> ------------------------------------------------------------------------------
> EditLive Enterprise is the world's most technically advanced content
> authoring tool. Experience the power of Track Changes, Inline Image
> Editing and ensure content is compliant with Accessibility Checking.
> http://p.sf.net/sfu/ephox-dev2dev
> _______________________________________________
> Emc-developers mailing list
> Emc-developers@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/emc-developers
>
------------------------------------------------------------------------------
EditLive Enterprise is the world's most technically advanced content
authoring tool. Experience the power of Track Changes, Inline Image
Editing and ensure content is compliant with Accessibility Checking.
http://p.sf.net/sfu/ephox-dev2dev
_______________________________________________
Emc-developers mailing list
Emc-developers@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-developers
