Mixxx stucks endless printing Warning [VinylControlProcessor 1]: VinylControlProcessor could not write signal quality report for VC index: 0

[Daniel Schürmann]

It has just happend testing my cdj branch:

Mixxx stucks in an endless Loop printing:
Warning [VinylControlProcessor 1]: VinylControlProcessor could not write signal quality report for VC index: 0

[Daniel Schürmann (daschuer)]

It happens after skin change.

I have tested again in eclipse/gdb and I receive a segfault after a while.

mixxx Default [C/C++ Application]
 mixxx [3572] [cores: 0,1,2,3]
  Thread [27] 3608 [core: 0] (Suspended : Container)
   pthread_cond_wait@@GLIBC_2.3.2() at pthread_cond_wait.S:185 0x7ffff34cbc84
   0x7ffff5ff606b
   0x7ffff5ff60a9
   start_thread() at pthread_create.c:311 0x7ffff34c7f6e
   clone() at clone.S:113 0x7ffff1e2d9cd
  Thread [26] 3607 [core: 2] (Suspended : Container)
   poll() at syscall-template.S:81 0x7ffff1e20f7d
   0x7ffff7bbc2c5
   0x7ffff7bbce9b
   start_thread() at pthread_create.c:311 0x7ffff34c7f6e
   clone() at clone.S:113 0x7ffff1e2d9cd
  Thread [25] 3606 [core: 2] (Suspended : Container)
   pthread_cond_wait@@GLIBC_2.3.2() at pthread_cond_wait.S:185 0x7ffff34cbc84
   wait() at qwaitcondition_unix.cpp:86 0x7ffff56c2406
   QWaitCondition::wait() at qwaitcondition_unix.cpp:158 0x7ffff56c2406
   QSemaphore::acquire() at qsemaphore.cpp:144 0x7ffff56be5eb
   VSyncThread::run() at vsyncthread.cpp:77 0x98dc0d
   QThreadPrivate::start() at qthread_unix.cpp:338 0x7ffff56c1f2f
   start_thread() at pthread_create.c:311 0x7ffff34c7f6e
   clone() at clone.S:113 0x7ffff1e2d9cd
  Thread [24] 3605 [core: 1] (Suspended : Container)
   poll() at syscall-template.S:81 0x7ffff1e20f7d
   0x7ffff064e6a4
   g_main_context_iteration() at 0x7ffff064e7ac
   QEventDispatcherGlib::processEvents() at qeventdispatcher_glib.cpp:424 0x7ffff57eea55
   QEventLoop::processEvents() at qeventloop.cpp:149 0x7ffff57c05ef
   QEventLoop::exec() at qeventloop.cpp:204 0x7ffff57c08e5
   QThread::exec() at qthread.cpp:542 0x7ffff56bf88f
   QThreadPrivate::start() at qthread_unix.cpp:338 0x7ffff56c1f2f
   start_thread() at pthread_create.c:311 0x7ffff34c7f6e
   clone() at clone.S:113 0x7ffff1e2d9cd
  Thread [23] 3604 [core: 1] (Suspended : Container)
   poll() at syscall-template.S:81 0x7ffff1e20f7d
   0x7ffff30b0198
   start_thread() at pthread_create.c:311 0x7ffff34c7f6e
   clone() at clone.S:113 0x7ffff1e2d9cd
  Thread [22] 3603 [core: 2] (Suspended : Container)
   pthread_cond_wait@@GLIBC_2.3.2() at pthread_cond_wait.S:185 0x7ffff34cbc84
   wait() at qwaitcondition_unix.cpp:86 0x7ffff56c2406
   QWaitCondition::wait() at qwaitcondition_unix.cpp:158 0x7ffff56c2406
   AnalyserQueue::dequeueNextBlocking() at analyserqueue.cpp:118 0x4af779
   AnalyserQueue::run() at analyserqueue.cpp:279 0x4b1bae
   QThreadPrivate::start() at qthread_unix.cpp:338 0x7ffff56c1f2f
   start_thread() at pthread_create.c:311 0x7ffff34c7f6e
   clone() at clone.S:113 0x7ffff1e2d9cd
  Thread [21] 3602 [core: 2] (Suspended : Container)
   pthread_cond_wait@@GLIBC_2.3.2() at pthread_cond_wait.S:185 0x7ffff34cbc84
   wait() at qwaitcondition_unix.cpp:86 0x7ffff56c2406
   QWaitCondition::wait() at qwaitcondition_unix.cpp:158 0x7ffff56c2406
   BrowseThread::run() at browsethread.cpp:82 0x77beda
   QThreadPrivate::start() at qthread_unix.cpp:338 0x7ffff56c1f2f
   start_thread() at pthread_create.c:311 0x7ffff34c7f6e
   clone() at clone.S:113 0x7ffff1e2d9cd
  Thread [20] 3601 [core: 1] (Suspended : Container)
   pthread_cond_wait@@GLIB...

[Daniel Schürmann (daschuer)]

Now the bug is gone without any change to the code :-/

[Daniel Schürmann (daschuer)]

Bug is back: Now I suspend Mixxx while printing continuous the error message:

mixxx Default [C/C++ Application]
 mixxx [5166] [cores: 0,1,3]
  Thread [27] 5199 [core: 1] (Suspended : Container)
   pthread_cond_wait@@GLIBC_2.3.2() at pthread_cond_wait.S:185 0x7ffff34cbc84
   0x7ffff5ff606b
   0x7ffff5ff60a9
   start_thread() at pthread_create.c:311 0x7ffff34c7f6e
   clone() at clone.S:113 0x7ffff1e2d9cd
  Thread [26] 5198 [core: 0] (Suspended : Container)
   poll() at syscall-template.S:81 0x7ffff1e20f7d
   0x7ffff7bbc2c5
   0x7ffff7bbce9b
   start_thread() at pthread_create.c:311 0x7ffff34c7f6e
   clone() at clone.S:113 0x7ffff1e2d9cd
  Thread [25] 5197 [core: 3] (Suspended : Container)
   pthread_cond_timedwait@@GLIBC_2.3.2() at pthread_cond_timedwait.S:238 0x7ffff34cc03e
   thread_sleep() at qthread_unix.cpp:475 0x7ffff56c0b7a
   QThread::usleep() at qthread_unix.cpp:513 0x7ffff56c1405
   VSyncThread::run() at vsyncthread.cpp:73 0x992578
   QThreadPrivate::start() at qthread_unix.cpp:338 0x7ffff56c1f2f
   start_thread() at pthread_create.c:311 0x7ffff34c7f6e
   clone() at clone.S:113 0x7ffff1e2d9cd
  Thread [24] 5196 [core: 1] (Suspended : Container)
   poll() at syscall-template.S:81 0x7ffff1e20f7d
   0x7ffff064e6a4
   g_main_context_iteration() at 0x7ffff064e7ac
   QEventDispatcherGlib::processEvents() at qeventdispatcher_glib.cpp:424 0x7ffff57eea55
   QEventLoop::processEvents() at qeventloop.cpp:149 0x7ffff57c05ef
   QEventLoop::exec() at qeventloop.cpp:204 0x7ffff57c08e5
   QThread::exec() at qthread.cpp:542 0x7ffff56bf88f
   QThreadPrivate::start() at qthread_unix.cpp:338 0x7ffff56c1f2f
   start_thread() at pthread_create.c:311 0x7ffff34c7f6e
   clone() at clone.S:113 0x7ffff1e2d9cd
  Thread [23] 5195 [core: 0] (Suspended : Container)
   poll() at syscall-template.S:81 0x7ffff1e20f7d
   0x7ffff30b0198
   start_thread() at pthread_create.c:311 0x7ffff34c7f6e
   clone() at clone.S:113 0x7ffff1e2d9cd
  Thread [22] 5194 [core: 3] (Suspended : Container)
   pthread_cond_wait@@GLIBC_2.3.2() at pthread_cond_wait.S:185 0x7ffff34cbc84
   wait() at qwaitcondition_unix.cpp:86 0x7ffff56c2406
   QWaitCondition::wait() at qwaitcondition_unix.cpp:158 0x7ffff56c2406
   AnalyserQueue::dequeueNextBlocking() at analyserqueue.cpp:118 0x4afe89
   AnalyserQueue::run() at analyserqueue.cpp:279 0x4b22be
   QThreadPrivate::start() at qthread_unix.cpp:338 0x7ffff56c1f2f
   start_thread() at pthread_create.c:311 0x7ffff34c7f6e
   clone() at clone.S:113 0x7ffff1e2d9cd
  Thread [21] 5193 [core: 1] (Suspended : Container)
   pthread_cond_wait@@GLIBC_2.3.2() at pthread_cond_wait.S:185 0x7ffff34cbc84
   wait() at qwaitcondition_unix.cpp:86 0x7ffff56c2406
   QWaitCondition::wait() at qwaitcondition_unix.cpp:158 0x7ffff56c2406
   BrowseThread::run() at browsethread.cpp:82 0x77be6a
   QThreadPrivate::start() at qthread_unix.cpp:338 0x7ffff56c1f2f
   start_thread() at pthread_create.c:311 0x7ffff34c7f6e
   clone() at clone.S:113 0x7ffff1e2d9cd
  Thread [20] 5192 [core: 1] (Suspended : Container)
   pthread_cond_wait@@GLIBC_2.3.2() at pthread_cond_wait.S:185 0x7ffff34cbc84
   wait() at qwaitcondition_unix.cpp:86 ...

[Daniel Schürmann (daschuer)]

<...more frames...> is:

QEventDispatcherGlib::processEvents() at qeventdispatcher_glib.cpp:424 0x7ffff57eea55
QGuiEventDispatcherGlib::processEvents() at qguieventdispatcher_glib.cpp:204 0x7ffff67c19d6
QEventLoop::processEvents() at qeventloop.cpp:149 0x7ffff57c05ef
QEventLoop::exec() at qeventloop.cpp:204 0x7ffff57c08e5
QCoreApplication::exec() at qcoreapplication.cpp:1.218 0x7ffff57c5e5b
QApplication::exec() at qapplication.cpp:3.828 0x7ffff671e34c
main() at main.cpp:343 0x46fa9b

[RJ Skerry-Ryan (rryan)]

Did you re-enable vinyl control when you tried to repro? That message is only written when VC is enabled and VC defaults off when you boot up.

That would print if the FIFO fills up and the manager is not running its timer to read from the signal quality FIFO. So maybe there is disagreement between the Processor and the Manager on whether signal quality reporting is needed.

Not sure if the segfault is related but it seems to be related to timers so maybe this is somehow related to the manager's timer callback?

[RJ Skerry-Ryan (rryan)]

Which VC inputs are enabled and which VC inputs have devices assigned?

[Daniel Schürmann (daschuer)]

It is only VC 1 configured. Channel 1 - 2
Vinyl control is off for both decks.

[RJ Skerry-Ryan (rryan)]

More details on Bug #1297657.

[Swiftb0y (swiftb0y)]

Mixxx now uses GitHub for bug tracking. This bug has been migrated to:
https://github.com/mixxxdj/mixxx/issues/7269