Fix thread safety/data races between game and sound effect mixer threads #10147

JGRennison · 2022-11-07T21:42:12Z

Motivation / Problem

There were data races on the MixerChannel active states. Marking a channel active form the game thread side was not properly synchronised with checking if it was active from the mixer thread, and vice versa when the mixer thread marked it no longer active.
Less importantly, the effect volume setting was not updated in a technically thread safe manner.

ThreadSanitizer output

==================
WARNING: ThreadSanitizer: data race (pid=643182)
  Write of size 1 at 0x557a9e63bbc6 by thread T17 (mutexes: write M3621):
    #0 WriteValue(void*, unsigned int, long long) /home/jgr/openttd/trunk/src/saveload/saveload.cpp:833 (openttd+0x15c3c0c)
    #1 IntSettingDesc::Write(void const*, int) const /home/jgr/openttd/trunk/src/settings.cpp:511 (openttd+0x1c5503e)
    #2 IntSettingDesc::MakeValueValidAndWrite(void const*, int) const /home/jgr/openttd/trunk/src/settings.cpp:443 (openttd+0x1c54c04)
    #3 IntSettingDesc::ParseValue(IniItem const*, void*) const /home/jgr/openttd/trunk/src/settings.cpp:612 (openttd+0x1c558fe)
    #4 IniLoadSettings /home/jgr/openttd/trunk/src/settings.cpp:605 (openttd+0x1c5574f)
    #5 HandleSettingDescs /home/jgr/openttd/trunk/src/settings.cpp:1159 (openttd+0x1c59113)
    #6 LoadFromConfig(bool) /home/jgr/openttd/trunk/src/settings.cpp:1222 (openttd+0x1c595f2)
    #7 AfterNewGRFScan::OnNewGRFsScanned() /home/jgr/openttd/trunk/src/openttd.cpp:440 (openttd+0x1b91c97)
    #8 DoScanNewGRFFiles(NewGRFScanCallback*) /home/jgr/openttd/trunk/src/newgrf_config.cpp:716 (openttd+0x1abba1a)
    #9 ScanNewGRFFiles(NewGRFScanCallback*) /home/jgr/openttd/trunk/src/newgrf_config.cpp:734 (openttd+0x1abbb2f)
    #10 GameLoop() /home/jgr/openttd/trunk/src/openttd.cpp:1453 (openttd+0x1b8f6e0)
    #11 VideoDriver::GameLoop() /home/jgr/openttd/trunk/src/video/video_driver.cpp:37 (openttd+0x16b9fab)
    #12 VideoDriver::GameThread() /home/jgr/openttd/trunk/src/video/video_driver.cpp:44 (openttd+0x16ba031)
    #13 VideoDriver::GameThreadThunk(VideoDriver*) /home/jgr/openttd/trunk/src/video/video_driver.cpp:81 (openttd+0x16ba1a4)
    #14 StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}::operator()(char const*, void (*&&)(VideoDriver*), VideoDriver*&&) const /home/jgr/openttd/trunk/src/video/../thread.h:65 (openttd+0x16bb89b)
    #15 void std::__invoke_impl<void, StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*>(std::__invoke_other, StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&&&)(VideoDriver*), VideoDriver*&&)#1}, char const*&&, void (*&&)(VideoDriver*), VideoDriver*&&) /usr/include/c++/9/bits/invoke.h:60 (openttd+0x16bcf7e)
    #16 _ZSt8__invokeIZ14StartNewThreadIPFvP11VideoDriverEJS2_EEbPSt6threadPKcOT_DpOT0_EUlS8_OS4_OS2_E_JS8_S4_S2_EENSt15__invoke_resultIS9_JDpSB_EE4typeESA_SD_ /usr/include/c++/9/bits/invoke.h:95 (openttd+0x16bcda7)
    #17 void std::thread::_Invoker<std::tuple<StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*> >::_M_invoke<0ul, 1ul, 2ul, 3ul>(std::_Index_tuple<0ul, 1ul, 2ul, 3ul>) /usr/include/c++/9/thread:244 (openttd+0x16bcbe4)
    #18 std::thread::_Invoker<std::tuple<StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*> >::operator()() /usr/include/c++/9/thread:251 (openttd+0x16bcb32)
    #19 std::thread::_State_impl<std::thread::_Invoker<std::tuple<StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*> > >::_M_run() /usr/include/c++/9/thread:195 (openttd+0x16bcae4)
    #20 <null> <null> (libstdc++.so.6+0xd6de3)

  Previous read of size 1 at 0x557a9e63bbc6 by thread T16 (mutexes: write M3544):
    #0 MxMixSamples(void*, unsigned int) /home/jgr/openttd/trunk/src/mixer.cpp:167 (openttd+0x1a05c9f)
    #1 fill_sound_buffer /home/jgr/openttd/trunk/src/sound/sdl2_s.cpp:31 (openttd+0x168e8d5)
    #2 <null> <null> (libSDL2-2.0.so.0+0x2556e)

  Location is global '_settings_client' of size 640 at 0x557a9e63b9a0 (openttd+0x000005bf2bc6)

  Mutex M3621 (0x7b6800000038) created at:
    #0 pthread_mutex_lock ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:4165 (libtsan.so.0+0x526fc)
    #1 __gthread_mutex_lock /usr/include/x86_64-linux-gnu/c++/9/bits/gthr-default.h:749 (openttd+0x11d0633)
    #2 std::mutex::lock() /usr/include/c++/9/bits/std_mutex.h:100 (openttd+0x11d234a)
    #3 std::lock_guard<std::mutex>::lock_guard(std::mutex&) /usr/include/c++/9/bits/std_mutex.h:159 (openttd+0x11d6388)
    #4 VideoDriver::Tick() /home/jgr/openttd/trunk/src/video/video_driver.cpp:125 (openttd+0x16ba732)
    #5 VideoDriver_SDL_Base::LoopOnce() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:619 (openttd+0x16aaf76)
    #6 VideoDriver_SDL_Base::MainLoop() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:637 (openttd+0x16aaff3)
    #7 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:813 (openttd+0x1b8ae4f)
    #8 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

  Mutex M3544 (0x7b0c000390f0) created at:
    #0 pthread_mutex_init ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:1220 (libtsan.so.0+0x4a616)
    #1 <null> <null> (libSDL2-2.0.so.0+0xee6e6)
    #2 DriverFactoryBase::SelectDriverImpl(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:122 (openttd+0x17e583e)
    #3 DriverFactoryBase::SelectDriver(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:87 (openttd+0x17e53c0)
    #4 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:800 (openttd+0x1b8ad7b)
    #5 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

  Thread T17 'ottd:game' (tid=643228, running) created by main thread at:
    #0 pthread_create ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:962 (libtsan.so.0+0x5ea79)
    #1 std::thread::_M_start_thread(std::unique_ptr<std::thread::_State, std::default_delete<std::thread::_State> >, void (*)()) <null> (libstdc++.so.6+0xd70a8)
    #2 bool StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&) /home/jgr/openttd/trunk/src/video/../thread.h:53 (openttd+0x16bb9ea)
    #3 VideoDriver::StartGameThread() /home/jgr/openttd/trunk/src/video/video_driver.cpp:87 (openttd+0x16ba2be)
    #4 VideoDriver_SDL_Base::MainLoop() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:634 (openttd+0x16aafd4)
    #5 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:813 (openttd+0x1b8ae4f)
    #6 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

  Thread T16 'SDLAudioP2' (tid=643227, running) created by main thread at:
    #0 pthread_create ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:962 (libtsan.so.0+0x5ea79)
    #1 <null> <null> (libSDL2-2.0.so.0+0xee1ba)
    #2 DriverFactoryBase::SelectDriverImpl(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:122 (openttd+0x17e583e)
    #3 DriverFactoryBase::SelectDriver(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:87 (openttd+0x17e53c0)
    #4 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:800 (openttd+0x1b8ad7b)
    #5 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

SUMMARY: ThreadSanitizer: data race /home/jgr/openttd/trunk/src/saveload/saveload.cpp:833 in WriteValue(void*, unsigned int, long long)
==================
==================
WARNING: ThreadSanitizer: data race (pid=643182)
  Write of size 1 at 0x557a9bd803e0 by thread T17 (mutexes: write M3621):
    #0 MxActivateChannel(MixerChannel*) /home/jgr/openttd/trunk/src/mixer.cpp:234 (openttd+0x1a06149)
    #1 StartSound /home/jgr/openttd/trunk/src/sound.cpp:193 (openttd+0x1d58f3a)
    #2 SndPlayScreenCoordFx /home/jgr/openttd/trunk/src/sound.cpp:259 (openttd+0x1d5933c)
    #3 SndPlayVehicleFx(unsigned short, Vehicle const*) /home/jgr/openttd/trunk/src/sound.cpp:283 (openttd+0x1d595ff)
    #4 Train::PlayLeaveStationSound() const /home/jgr/openttd/trunk/src/train_cmd.cpp:2116 (openttd+0x1ed1b58)
    #5 Vehicle::HandleLoading(bool) /home/jgr/openttd/trunk/src/vehicle.cpp:2333 (openttd+0x1f068db)
    #6 TrainLocoHandler /home/jgr/openttd/trunk/src/train_cmd.cpp:3870 (openttd+0x1ed8a46)
    #7 Train::Tick() /home/jgr/openttd/trunk/src/train_cmd.cpp:4007 (openttd+0x1ed943c)
    #8 CallVehicleTicks() /home/jgr/openttd/trunk/src/vehicle.cpp:973 (openttd+0x1effccf)
    #9 StateGameLoop() /home/jgr/openttd/trunk/src/openttd.cpp:1396 (openttd+0x1b8f316)
    #10 GameLoop() /home/jgr/openttd/trunk/src/openttd.cpp:1492 (openttd+0x1b8f929)
    #11 VideoDriver::GameLoop() /home/jgr/openttd/trunk/src/video/video_driver.cpp:37 (openttd+0x16b9fab)
    #12 VideoDriver::GameThread() /home/jgr/openttd/trunk/src/video/video_driver.cpp:44 (openttd+0x16ba031)
    #13 VideoDriver::GameThreadThunk(VideoDriver*) /home/jgr/openttd/trunk/src/video/video_driver.cpp:81 (openttd+0x16ba1a4)
    #14 StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}::operator()(char const*, void (*&&)(VideoDriver*), VideoDriver*&&) const /home/jgr/openttd/trunk/src/video/../thread.h:65 (openttd+0x16bb89b)
    #15 void std::__invoke_impl<void, StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*>(std::__invoke_other, StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&&&)(VideoDriver*), VideoDriver*&&)#1}, char const*&&, void (*&&)(VideoDriver*), VideoDriver*&&) /usr/include/c++/9/bits/invoke.h:60 (openttd+0x16bcf7e)
    #16 _ZSt8__invokeIZ14StartNewThreadIPFvP11VideoDriverEJS2_EEbPSt6threadPKcOT_DpOT0_EUlS8_OS4_OS2_E_JS8_S4_S2_EENSt15__invoke_resultIS9_JDpSB_EE4typeESA_SD_ /usr/include/c++/9/bits/invoke.h:95 (openttd+0x16bcda7)
    #17 void std::thread::_Invoker<std::tuple<StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*> >::_M_invoke<0ul, 1ul, 2ul, 3ul>(std::_Index_tuple<0ul, 1ul, 2ul, 3ul>) /usr/include/c++/9/thread:244 (openttd+0x16bcbe4)
    #18 std::thread::_Invoker<std::tuple<StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*> >::operator()() /usr/include/c++/9/thread:251 (openttd+0x16bcb32)
    #19 std::thread::_State_impl<std::thread::_Invoker<std::tuple<StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*> > >::_M_run() /usr/include/c++/9/thread:195 (openttd+0x16bcae4)
    #20 <null> <null> (libstdc++.so.6+0xd6de3)

  Previous read of size 1 at 0x557a9bd803e0 by thread T16 (mutexes: write M3544):
    #0 MxMixSamples(void*, unsigned int) /home/jgr/openttd/trunk/src/mixer.cpp:173 (openttd+0x1a05d20)
    #1 fill_sound_buffer /home/jgr/openttd/trunk/src/sound/sdl2_s.cpp:31 (openttd+0x168e8d5)
    #2 <null> <null> (libSDL2-2.0.so.0+0x2556e)

  Location is global '_channels' of size 384 at 0x557a9bd803e0 (openttd+0x0000033373e0)

  Mutex M3621 (0x7b6800000038) created at:
    #0 pthread_mutex_lock ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:4165 (libtsan.so.0+0x526fc)
    #1 __gthread_mutex_lock /usr/include/x86_64-linux-gnu/c++/9/bits/gthr-default.h:749 (openttd+0x11d0633)
    #2 std::mutex::lock() /usr/include/c++/9/bits/std_mutex.h:100 (openttd+0x11d234a)
    #3 std::lock_guard<std::mutex>::lock_guard(std::mutex&) /usr/include/c++/9/bits/std_mutex.h:159 (openttd+0x11d6388)
    #4 VideoDriver::Tick() /home/jgr/openttd/trunk/src/video/video_driver.cpp:125 (openttd+0x16ba732)
    #5 VideoDriver_SDL_Base::LoopOnce() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:619 (openttd+0x16aaf76)
    #6 VideoDriver_SDL_Base::MainLoop() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:637 (openttd+0x16aaff3)
    #7 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:813 (openttd+0x1b8ae4f)
    #8 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

  Mutex M3544 (0x7b0c000390f0) created at:
    #0 pthread_mutex_init ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:1220 (libtsan.so.0+0x4a616)
    #1 <null> <null> (libSDL2-2.0.so.0+0xee6e6)
    #2 DriverFactoryBase::SelectDriverImpl(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:122 (openttd+0x17e583e)
    #3 DriverFactoryBase::SelectDriver(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:87 (openttd+0x17e53c0)
    #4 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:800 (openttd+0x1b8ad7b)
    #5 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

  Thread T17 'ottd:game' (tid=643228, running) created by main thread at:
    #0 pthread_create ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:962 (libtsan.so.0+0x5ea79)
    #1 std::thread::_M_start_thread(std::unique_ptr<std::thread::_State, std::default_delete<std::thread::_State> >, void (*)()) <null> (libstdc++.so.6+0xd70a8)
    #2 bool StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&) /home/jgr/openttd/trunk/src/video/../thread.h:53 (openttd+0x16bb9ea)
    #3 VideoDriver::StartGameThread() /home/jgr/openttd/trunk/src/video/video_driver.cpp:87 (openttd+0x16ba2be)
    #4 VideoDriver_SDL_Base::MainLoop() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:634 (openttd+0x16aafd4)
    #5 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:813 (openttd+0x1b8ae4f)
    #6 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

  Thread T16 'SDLAudioP2' (tid=643227, running) created by main thread at:
    #0 pthread_create ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:962 (libtsan.so.0+0x5ea79)
    #1 <null> <null> (libSDL2-2.0.so.0+0xee1ba)
    #2 DriverFactoryBase::SelectDriverImpl(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:122 (openttd+0x17e583e)
    #3 DriverFactoryBase::SelectDriver(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:87 (openttd+0x17e53c0)
    #4 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:800 (openttd+0x1b8ad7b)
    #5 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

SUMMARY: ThreadSanitizer: data race /home/jgr/openttd/trunk/src/mixer.cpp:234 in MxActivateChannel(MixerChannel*)
==================
==================
WARNING: ThreadSanitizer: data race (pid=643182)
  Read of size 1 at 0x557a9bd80408 by thread T16 (mutexes: write M3544):
    #0 MxMixSamples(void*, unsigned int) /home/jgr/openttd/trunk/src/mixer.cpp:174 (openttd+0x1a05d3b)
    #1 fill_sound_buffer /home/jgr/openttd/trunk/src/sound/sdl2_s.cpp:31 (openttd+0x168e8d5)
    #2 <null> <null> (libSDL2-2.0.so.0+0x2556e)

  Previous write of size 1 at 0x557a9bd80408 by thread T17 (mutexes: write M3621):
    #0 MxSetChannelRawSrc(MixerChannel*, signed char*, unsigned long, unsigned int, bool) /home/jgr/openttd/trunk/src/mixer.cpp:214 (openttd+0x1a05fef)
    #1 SetBankSource /home/jgr/openttd/trunk/src/sound.cpp:153 (openttd+0x1d58bf6)
    #2 StartSound /home/jgr/openttd/trunk/src/sound.cpp:187 (openttd+0x1d58eeb)
    #3 SndPlayScreenCoordFx /home/jgr/openttd/trunk/src/sound.cpp:259 (openttd+0x1d5933c)
    #4 SndPlayVehicleFx(unsigned short, Vehicle const*) /home/jgr/openttd/trunk/src/sound.cpp:283 (openttd+0x1d595ff)
    #5 Train::PlayLeaveStationSound() const /home/jgr/openttd/trunk/src/train_cmd.cpp:2116 (openttd+0x1ed1b58)
    #6 Vehicle::HandleLoading(bool) /home/jgr/openttd/trunk/src/vehicle.cpp:2333 (openttd+0x1f068db)
    #7 TrainLocoHandler /home/jgr/openttd/trunk/src/train_cmd.cpp:3870 (openttd+0x1ed8a46)
    #8 Train::Tick() /home/jgr/openttd/trunk/src/train_cmd.cpp:4007 (openttd+0x1ed943c)
    #9 CallVehicleTicks() /home/jgr/openttd/trunk/src/vehicle.cpp:973 (openttd+0x1effccf)
    #10 StateGameLoop() /home/jgr/openttd/trunk/src/openttd.cpp:1396 (openttd+0x1b8f316)
    #11 GameLoop() /home/jgr/openttd/trunk/src/openttd.cpp:1492 (openttd+0x1b8f929)
    #12 VideoDriver::GameLoop() /home/jgr/openttd/trunk/src/video/video_driver.cpp:37 (openttd+0x16b9fab)
    #13 VideoDriver::GameThread() /home/jgr/openttd/trunk/src/video/video_driver.cpp:44 (openttd+0x16ba031)
    #14 VideoDriver::GameThreadThunk(VideoDriver*) /home/jgr/openttd/trunk/src/video/video_driver.cpp:81 (openttd+0x16ba1a4)
    #15 StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}::operator()(char const*, void (*&&)(VideoDriver*), VideoDriver*&&) const /home/jgr/openttd/trunk/src/video/../thread.h:65 (openttd+0x16bb89b)
    #16 void std::__invoke_impl<void, StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*>(std::__invoke_other, StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&&&)(VideoDriver*), VideoDriver*&&)#1}, char const*&&, void (*&&)(VideoDriver*), VideoDriver*&&) /usr/include/c++/9/bits/invoke.h:60 (openttd+0x16bcf7e)
    #17 _ZSt8__invokeIZ14StartNewThreadIPFvP11VideoDriverEJS2_EEbPSt6threadPKcOT_DpOT0_EUlS8_OS4_OS2_E_JS8_S4_S2_EENSt15__invoke_resultIS9_JDpSB_EE4typeESA_SD_ /usr/include/c++/9/bits/invoke.h:95 (openttd+0x16bcda7)
    #18 void std::thread::_Invoker<std::tuple<StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*> >::_M_invoke<0ul, 1ul, 2ul, 3ul>(std::_Index_tuple<0ul, 1ul, 2ul, 3ul>) /usr/include/c++/9/thread:244 (openttd+0x16bcbe4)
    #19 std::thread::_Invoker<std::tuple<StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*> >::operator()() /usr/include/c++/9/thread:251 (openttd+0x16bcb32)
    #20 std::thread::_State_impl<std::thread::_Invoker<std::tuple<StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*> > >::_M_run() /usr/include/c++/9/thread:195 (openttd+0x16bcae4)
    #21 <null> <null> (libstdc++.so.6+0xd6de3)

  Location is global '_channels' of size 384 at 0x557a9bd803e0 (openttd+0x000003337408)

  Mutex M3544 (0x7b0c000390f0) created at:
    #0 pthread_mutex_init ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:1220 (libtsan.so.0+0x4a616)
    #1 <null> <null> (libSDL2-2.0.so.0+0xee6e6)
    #2 DriverFactoryBase::SelectDriverImpl(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:122 (openttd+0x17e583e)
    #3 DriverFactoryBase::SelectDriver(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:87 (openttd+0x17e53c0)
    #4 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:800 (openttd+0x1b8ad7b)
    #5 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

  Mutex M3621 (0x7b6800000038) created at:
    #0 pthread_mutex_lock ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:4165 (libtsan.so.0+0x526fc)
    #1 __gthread_mutex_lock /usr/include/x86_64-linux-gnu/c++/9/bits/gthr-default.h:749 (openttd+0x11d0633)
    #2 std::mutex::lock() /usr/include/c++/9/bits/std_mutex.h:100 (openttd+0x11d234a)
    #3 std::lock_guard<std::mutex>::lock_guard(std::mutex&) /usr/include/c++/9/bits/std_mutex.h:159 (openttd+0x11d6388)
    #4 VideoDriver::Tick() /home/jgr/openttd/trunk/src/video/video_driver.cpp:125 (openttd+0x16ba732)
    #5 VideoDriver_SDL_Base::LoopOnce() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:619 (openttd+0x16aaf76)
    #6 VideoDriver_SDL_Base::MainLoop() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:637 (openttd+0x16aaff3)
    #7 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:813 (openttd+0x1b8ae4f)
    #8 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

  Thread T16 'SDLAudioP2' (tid=643227, running) created by main thread at:
    #0 pthread_create ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:962 (libtsan.so.0+0x5ea79)
    #1 <null> <null> (libSDL2-2.0.so.0+0xee1ba)
    #2 DriverFactoryBase::SelectDriverImpl(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:122 (openttd+0x17e583e)
    #3 DriverFactoryBase::SelectDriver(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:87 (openttd+0x17e53c0)
    #4 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:800 (openttd+0x1b8ad7b)
    #5 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

  Thread T17 'ottd:game' (tid=643228, running) created by main thread at:
    #0 pthread_create ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:962 (libtsan.so.0+0x5ea79)
    #1 std::thread::_M_start_thread(std::unique_ptr<std::thread::_State, std::default_delete<std::thread::_State> >, void (*)()) <null> (libstdc++.so.6+0xd70a8)
    #2 bool StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&) /home/jgr/openttd/trunk/src/video/../thread.h:53 (openttd+0x16bb9ea)
    #3 VideoDriver::StartGameThread() /home/jgr/openttd/trunk/src/video/video_driver.cpp:87 (openttd+0x16ba2be)
    #4 VideoDriver_SDL_Base::MainLoop() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:634 (openttd+0x16aafd4)
    #5 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:813 (openttd+0x1b8ae4f)
    #6 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

SUMMARY: ThreadSanitizer: data race /home/jgr/openttd/trunk/src/mixer.cpp:174 in MxMixSamples(void*, unsigned int)
==================
==================
WARNING: ThreadSanitizer: data race (pid=643182)
  Read of size 4 at 0x557a9bd803fc by thread T16 (mutexes: write M3544):
    #0 mix_int16 /home/jgr/openttd/trunk/src/mixer.cpp:68 (openttd+0x1a053db)
    #1 MxMixSamples(void*, unsigned int) /home/jgr/openttd/trunk/src/mixer.cpp:175 (openttd+0x1a05d5e)
    #2 fill_sound_buffer /home/jgr/openttd/trunk/src/sound/sdl2_s.cpp:31 (openttd+0x168e8d5)
    #3 <null> <null> (libSDL2-2.0.so.0+0x2556e)

  Previous write of size 4 at 0x557a9bd803fc by thread T17 (mutexes: write M3621):
    #0 MxSetChannelRawSrc(MixerChannel*, signed char*, unsigned long, unsigned int, bool) /home/jgr/openttd/trunk/src/mixer.cpp:213 (openttd+0x1a05fd8)
    #1 SetBankSource /home/jgr/openttd/trunk/src/sound.cpp:153 (openttd+0x1d58bf6)
    #2 StartSound /home/jgr/openttd/trunk/src/sound.cpp:187 (openttd+0x1d58eeb)
    #3 SndPlayScreenCoordFx /home/jgr/openttd/trunk/src/sound.cpp:259 (openttd+0x1d5933c)
    #4 SndPlayVehicleFx(unsigned short, Vehicle const*) /home/jgr/openttd/trunk/src/sound.cpp:283 (openttd+0x1d595ff)
    #5 Train::PlayLeaveStationSound() const /home/jgr/openttd/trunk/src/train_cmd.cpp:2116 (openttd+0x1ed1b58)
    #6 Vehicle::HandleLoading(bool) /home/jgr/openttd/trunk/src/vehicle.cpp:2333 (openttd+0x1f068db)
    #7 TrainLocoHandler /home/jgr/openttd/trunk/src/train_cmd.cpp:3870 (openttd+0x1ed8a46)
    #8 Train::Tick() /home/jgr/openttd/trunk/src/train_cmd.cpp:4007 (openttd+0x1ed943c)
    #9 CallVehicleTicks() /home/jgr/openttd/trunk/src/vehicle.cpp:973 (openttd+0x1effccf)
    #10 StateGameLoop() /home/jgr/openttd/trunk/src/openttd.cpp:1396 (openttd+0x1b8f316)
    #11 GameLoop() /home/jgr/openttd/trunk/src/openttd.cpp:1492 (openttd+0x1b8f929)
    #12 VideoDriver::GameLoop() /home/jgr/openttd/trunk/src/video/video_driver.cpp:37 (openttd+0x16b9fab)
    #13 VideoDriver::GameThread() /home/jgr/openttd/trunk/src/video/video_driver.cpp:44 (openttd+0x16ba031)
    #14 VideoDriver::GameThreadThunk(VideoDriver*) /home/jgr/openttd/trunk/src/video/video_driver.cpp:81 (openttd+0x16ba1a4)
    #15 StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}::operator()(char const*, void (*&&)(VideoDriver*), VideoDriver*&&) const /home/jgr/openttd/trunk/src/video/../thread.h:65 (openttd+0x16bb89b)
    #16 void std::__invoke_impl<void, StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*>(std::__invoke_other, StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&&&)(VideoDriver*), VideoDriver*&&)#1}, char const*&&, void (*&&)(VideoDriver*), VideoDriver*&&) /usr/include/c++/9/bits/invoke.h:60 (openttd+0x16bcf7e)
    #17 _ZSt8__invokeIZ14StartNewThreadIPFvP11VideoDriverEJS2_EEbPSt6threadPKcOT_DpOT0_EUlS8_OS4_OS2_E_JS8_S4_S2_EENSt15__invoke_resultIS9_JDpSB_EE4typeESA_SD_ /usr/include/c++/9/bits/invoke.h:95 (openttd+0x16bcda7)
    #18 void std::thread::_Invoker<std::tuple<StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*> >::_M_invoke<0ul, 1ul, 2ul, 3ul>(std::_Index_tuple<0ul, 1ul, 2ul, 3ul>) /usr/include/c++/9/thread:244 (openttd+0x16bcbe4)
    #19 std::thread::_Invoker<std::tuple<StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*> >::operator()() /usr/include/c++/9/thread:251 (openttd+0x16bcb32)
    #20 std::thread::_State_impl<std::thread::_Invoker<std::tuple<StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*> > >::_M_run() /usr/include/c++/9/thread:195 (openttd+0x16bcae4)
    #21 <null> <null> (libstdc++.so.6+0xd6de3)

  Location is global '_channels' of size 384 at 0x557a9bd803e0 (openttd+0x0000033373fc)

  Mutex M3544 (0x7b0c000390f0) created at:
    #0 pthread_mutex_init ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:1220 (libtsan.so.0+0x4a616)
    #1 <null> <null> (libSDL2-2.0.so.0+0xee6e6)
    #2 DriverFactoryBase::SelectDriverImpl(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:122 (openttd+0x17e583e)
    #3 DriverFactoryBase::SelectDriver(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:87 (openttd+0x17e53c0)
    #4 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:800 (openttd+0x1b8ad7b)
    #5 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

  Mutex M3621 (0x7b6800000038) created at:
    #0 pthread_mutex_lock ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:4165 (libtsan.so.0+0x526fc)
    #1 __gthread_mutex_lock /usr/include/x86_64-linux-gnu/c++/9/bits/gthr-default.h:749 (openttd+0x11d0633)
    #2 std::mutex::lock() /usr/include/c++/9/bits/std_mutex.h:100 (openttd+0x11d234a)
    #3 std::lock_guard<std::mutex>::lock_guard(std::mutex&) /usr/include/c++/9/bits/std_mutex.h:159 (openttd+0x11d6388)
    #4 VideoDriver::Tick() /home/jgr/openttd/trunk/src/video/video_driver.cpp:125 (openttd+0x16ba732)
    #5 VideoDriver_SDL_Base::LoopOnce() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:619 (openttd+0x16aaf76)
    #6 VideoDriver_SDL_Base::MainLoop() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:637 (openttd+0x16aaff3)
    #7 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:813 (openttd+0x1b8ae4f)
    #8 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

  Thread T16 'SDLAudioP2' (tid=643227, running) created by main thread at:
    #0 pthread_create ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:962 (libtsan.so.0+0x5ea79)
    #1 <null> <null> (libSDL2-2.0.so.0+0xee1ba)
    #2 DriverFactoryBase::SelectDriverImpl(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:122 (openttd+0x17e583e)
    #3 DriverFactoryBase::SelectDriver(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:87 (openttd+0x17e53c0)
    #4 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:800 (openttd+0x1b8ad7b)
    #5 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

  Thread T17 'ottd:game' (tid=643228, running) created by main thread at:
    #0 pthread_create ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:962 (libtsan.so.0+0x5ea79)
    #1 std::thread::_M_start_thread(std::unique_ptr<std::thread::_State, std::default_delete<std::thread::_State> >, void (*)()) <null> (libstdc++.so.6+0xd70a8)
    #2 bool StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&) /home/jgr/openttd/trunk/src/video/../thread.h:53 (openttd+0x16bb9ea)
    #3 VideoDriver::StartGameThread() /home/jgr/openttd/trunk/src/video/video_driver.cpp:87 (openttd+0x16ba2be)
    #4 VideoDriver_SDL_Base::MainLoop() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:634 (openttd+0x16aafd4)
    #5 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:813 (openttd+0x1b8ae4f)
    #6 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

SUMMARY: ThreadSanitizer: data race /home/jgr/openttd/trunk/src/mixer.cpp:68 in mix_int16
==================
==================
WARNING: ThreadSanitizer: data race (pid=643182)
  Write of size 1 at 0x557a9bd80440 by thread T17 (mutexes: write M3621):
    #0 MxActivateChannel(MixerChannel*) /home/jgr/openttd/trunk/src/mixer.cpp:234 (openttd+0x1a06149)
    #1 StartSound /home/jgr/openttd/trunk/src/sound.cpp:193 (openttd+0x1d58f3a)
    #2 SndPlayScreenCoordFx /home/jgr/openttd/trunk/src/sound.cpp:259 (openttd+0x1d5933c)
    #3 SndPlayVehicleFx(unsigned short, Vehicle const*) /home/jgr/openttd/trunk/src/sound.cpp:283 (openttd+0x1d595ff)
    #4 PlayShipSound /home/jgr/openttd/trunk/src/ship_cmd.cpp:278 (openttd+0x1d232e9)
    #5 Ship::PlayLeaveStationSound() const /home/jgr/openttd/trunk/src/ship_cmd.cpp:284 (openttd+0x1d23338)
    #6 Vehicle::HandleLoading(bool) /home/jgr/openttd/trunk/src/vehicle.cpp:2333 (openttd+0x1f068db)
    #7 ShipController /home/jgr/openttd/trunk/src/ship_cmd.cpp:658 (openttd+0x1d24a7a)
    #8 Ship::Tick() /home/jgr/openttd/trunk/src/ship_cmd.cpp:841 (openttd+0x1d25902)
    #9 CallVehicleTicks() /home/jgr/openttd/trunk/src/vehicle.cpp:973 (openttd+0x1effccf)
    #10 StateGameLoop() /home/jgr/openttd/trunk/src/openttd.cpp:1396 (openttd+0x1b8f316)
    #11 GameLoop() /home/jgr/openttd/trunk/src/openttd.cpp:1492 (openttd+0x1b8f929)
    #12 VideoDriver::GameLoop() /home/jgr/openttd/trunk/src/video/video_driver.cpp:37 (openttd+0x16b9fab)
    #13 VideoDriver::GameThread() /home/jgr/openttd/trunk/src/video/video_driver.cpp:44 (openttd+0x16ba031)
    #14 VideoDriver::GameThreadThunk(VideoDriver*) /home/jgr/openttd/trunk/src/video/video_driver.cpp:81 (openttd+0x16ba1a4)
    #15 StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}::operator()(char const*, void (*&&)(VideoDriver*), VideoDriver*&&) const /home/jgr/openttd/trunk/src/video/../thread.h:65 (openttd+0x16bb89b)
    #16 void std::__invoke_impl<void, StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*>(std::__invoke_other, StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&&&)(VideoDriver*), VideoDriver*&&)#1}, char const*&&, void (*&&)(VideoDriver*), VideoDriver*&&) /usr/include/c++/9/bits/invoke.h:60 (openttd+0x16bcf7e)
    #17 _ZSt8__invokeIZ14StartNewThreadIPFvP11VideoDriverEJS2_EEbPSt6threadPKcOT_DpOT0_EUlS8_OS4_OS2_E_JS8_S4_S2_EENSt15__invoke_resultIS9_JDpSB_EE4typeESA_SD_ /usr/include/c++/9/bits/invoke.h:95 (openttd+0x16bcda7)
    #18 void std::thread::_Invoker<std::tuple<StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*> >::_M_invoke<0ul, 1ul, 2ul, 3ul>(std::_Index_tuple<0ul, 1ul, 2ul, 3ul>) /usr/include/c++/9/thread:244 (openttd+0x16bcbe4)
    #19 std::thread::_Invoker<std::tuple<StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*> >::operator()() /usr/include/c++/9/thread:251 (openttd+0x16bcb32)
    #20 std::thread::_State_impl<std::thread::_Invoker<std::tuple<StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&)::{lambda(char const*, void (*&&)(VideoDriver*), VideoDriver*&&)#1}, char const*, void (*)(VideoDriver*), VideoDriver*> > >::_M_run() /usr/include/c++/9/thread:195 (openttd+0x16bcae4)
    #21 <null> <null> (libstdc++.so.6+0xd6de3)

  Previous read of size 1 at 0x557a9bd80440 by thread T16 (mutexes: write M3544):
    #0 MxMixSamples(void*, unsigned int) /home/jgr/openttd/trunk/src/mixer.cpp:173 (openttd+0x1a05d20)
    #1 fill_sound_buffer /home/jgr/openttd/trunk/src/sound/sdl2_s.cpp:31 (openttd+0x168e8d5)
    #2 <null> <null> (libSDL2-2.0.so.0+0x2556e)

  Location is global '_channels' of size 384 at 0x557a9bd803e0 (openttd+0x000003337440)

  Mutex M3621 (0x7b6800000038) created at:
    #0 pthread_mutex_lock ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:4165 (libtsan.so.0+0x526fc)
    #1 __gthread_mutex_lock /usr/include/x86_64-linux-gnu/c++/9/bits/gthr-default.h:749 (openttd+0x11d0633)
    #2 std::mutex::lock() /usr/include/c++/9/bits/std_mutex.h:100 (openttd+0x11d234a)
    #3 std::lock_guard<std::mutex>::lock_guard(std::mutex&) /usr/include/c++/9/bits/std_mutex.h:159 (openttd+0x11d6388)
    #4 VideoDriver::Tick() /home/jgr/openttd/trunk/src/video/video_driver.cpp:125 (openttd+0x16ba732)
    #5 VideoDriver_SDL_Base::LoopOnce() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:619 (openttd+0x16aaf76)
    #6 VideoDriver_SDL_Base::MainLoop() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:637 (openttd+0x16aaff3)
    #7 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:813 (openttd+0x1b8ae4f)
    #8 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

  Mutex M3544 (0x7b0c000390f0) created at:
    #0 pthread_mutex_init ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:1220 (libtsan.so.0+0x4a616)
    #1 <null> <null> (libSDL2-2.0.so.0+0xee6e6)
    #2 DriverFactoryBase::SelectDriverImpl(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:122 (openttd+0x17e583e)
    #3 DriverFactoryBase::SelectDriver(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:87 (openttd+0x17e53c0)
    #4 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:800 (openttd+0x1b8ad7b)
    #5 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

  Thread T17 'ottd:game' (tid=643228, running) created by main thread at:
    #0 pthread_create ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:962 (libtsan.so.0+0x5ea79)
    #1 std::thread::_M_start_thread(std::unique_ptr<std::thread::_State, std::default_delete<std::thread::_State> >, void (*)()) <null> (libstdc++.so.6+0xd70a8)
    #2 bool StartNewThread<void (*)(VideoDriver*), VideoDriver*>(std::thread*, char const*, void (*&&)(VideoDriver*), VideoDriver*&&) /home/jgr/openttd/trunk/src/video/../thread.h:53 (openttd+0x16bb9ea)
    #3 VideoDriver::StartGameThread() /home/jgr/openttd/trunk/src/video/video_driver.cpp:87 (openttd+0x16ba2be)
    #4 VideoDriver_SDL_Base::MainLoop() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:634 (openttd+0x16aafd4)
    #5 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:813 (openttd+0x1b8ae4f)
    #6 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

  Thread T16 'SDLAudioP2' (tid=643227, running) created by main thread at:
    #0 pthread_create ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:962 (libtsan.so.0+0x5ea79)
    #1 <null> <null> (libSDL2-2.0.so.0+0xee1ba)
    #2 DriverFactoryBase::SelectDriverImpl(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:122 (openttd+0x17e583e)
    #3 DriverFactoryBase::SelectDriver(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:87 (openttd+0x17e53c0)
    #4 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:800 (openttd+0x1b8ad7b)
    #5 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488dd5)

SUMMARY: ThreadSanitizer: data race /home/jgr/openttd/trunk/src/mixer.cpp:234 in MxActivateChannel(MixerChannel*)
==================

The reporting of performance measurements via PerformanceMeasurer framerate(PFE_SOUND) was also not thread safe.

ThreadSanitizer output (performance measurement)

==================
==================
WARNING: ThreadSanitizer: data race (pid=734716)
  Read of size 4 at 0x556dabf0b8c8 by main thread (mutexes: write M1016, write M1017):
    #0 FramerateWindow::UpdateWidgetSize(int, Dimension*, Dimension const&, Dimension*, Dimension*) /home/jgr/openttd/trunk/src/framerate_gui.cpp:552 (openttd+0x184eb22)
    #1 NWidgetLeaf::SetupSmallestSize(Window*, bool) /home/jgr/openttd/trunk/src/widget.cpp:2634 (openttd+0x1f9d891)
    #2 NWidgetHorizontal::SetupSmallestSize(Window*, bool) /home/jgr/openttd/trunk/src/widget.cpp:1269 (openttd+0x1f940e7)
    #3 NWidgetVertical::SetupSmallestSize(Window*, bool) /home/jgr/openttd/trunk/src/widget.cpp:1454 (openttd+0x1f954df)
    #4 NWidgetVertical::SetupSmallestSize(Window*, bool) /home/jgr/openttd/trunk/src/widget.cpp:1454 (openttd+0x1f954df)
    #5 NWidgetBackground::SetupSmallestSize(Window*, bool) /home/jgr/openttd/trunk/src/widget.cpp:1934 (openttd+0x1f98e62)
    #6 NWidgetHorizontal::SetupSmallestSize(Window*, bool) /home/jgr/openttd/trunk/src/widget.cpp:1269 (openttd+0x1f940e7)
    #7 NWidgetVertical::SetupSmallestSize(Window*, bool) /home/jgr/openttd/trunk/src/widget.cpp:1454 (openttd+0x1f954df)
    #8 NWidgetStacked::SetupSmallestSize(Window*, bool) /home/jgr/openttd/trunk/src/widget.cpp:1125 (openttd+0x1f93089)
    #9 NWidgetVertical::SetupSmallestSize(Window*, bool) /home/jgr/openttd/trunk/src/widget.cpp:1454 (openttd+0x1f954df)
    #10 Window::InitializeData(int) /home/jgr/openttd/trunk/src/window.cpp:1411 (openttd+0x1fa7f54)
    #11 Window::FinishInitNested(int) /home/jgr/openttd/trunk/src/window.cpp:1778 (openttd+0x1faa89c)
    #12 Window::InitNested(int) /home/jgr/openttd/trunk/src/window.cpp:1792 (openttd+0x1faaab1)
    #13 FramerateWindow::FramerateWindow(WindowDesc*, int) /home/jgr/openttd/trunk/src/framerate_gui.cpp:433 (openttd+0x184e0fc)
    #14 FramerateWindow* AllocateWindowDescFront<FramerateWindow>(WindowDesc*, int, bool) /home/jgr/openttd/trunk/src/window_gui.h:944 (openttd+0x1850fa8)
    #15 ShowFramerateWindow() /home/jgr/openttd/trunk/src/framerate_gui.cpp:1009 (openttd+0x184c3c1)
    #16 ConFramerateWindow /home/jgr/openttd/trunk/src/console_cmds.cpp:2286 (openttd+0x17938ca)
    #17 IConsoleCmdExec(char const*, unsigned int) /home/jgr/openttd/trunk/src/console.cpp:394 (openttd+0x17799cd)
    #18 IConsoleWindow::OnKeyPress(char32_t, unsigned short) /home/jgr/openttd/trunk/src/console_gui.cpp:249 (openttd+0x17b8c5d)
    #19 HandleKeypress(unsigned int, char32_t) /home/jgr/openttd/trunk/src/window.cpp:2634 (openttd+0x1faf89f)
    #20 VideoDriver_SDL_Base::PollEvent() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:451 (openttd+0x16aa3d0)
    #21 VideoDriver::Tick() /home/jgr/openttd/trunk/src/video/video_driver.cpp:133 (openttd+0x16ba7b1)
    #22 VideoDriver_SDL_Base::LoopOnce() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:619 (openttd+0x16aafb6)
    #23 VideoDriver_SDL_Base::MainLoop() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:637 (openttd+0x16ab033)
    #24 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:815 (openttd+0x1b8b5b9)
    #25 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488e15)

  Previous write of size 4 at 0x556dabf0b8c8 by thread T2 (mutexes: write M940):
    #0 Add /home/jgr/openttd/trunk/src/framerate_gui.cpp:79 (openttd+0x184b466)
    #1 PerformanceMeasurer::~PerformanceMeasurer() /home/jgr/openttd/trunk/src/framerate_gui.cpp:254 (openttd+0x184bf7e)
    #2 MxMixSamples(void*, unsigned int) /home/jgr/openttd/trunk/src/mixer.cpp:146 (openttd+0x1a05f1f)
    #3 fill_sound_buffer /home/jgr/openttd/trunk/src/sound/sdl2_s.cpp:31 (openttd+0x168e915)
    #4 <null> <null> (libSDL2-2.0.so.0+0x2556e)

  Location is global '(anonymous namespace)::_pf_data' of size 238728 at 0x556dabef3700 (openttd+0x0000032c68c8)

  Mutex M1016 (0x7b6800000060) created at:
    #0 pthread_mutex_lock ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:4165 (libtsan.so.0+0x526fc)
    #1 __gthread_mutex_lock /usr/include/x86_64-linux-gnu/c++/9/bits/gthr-default.h:749 (openttd+0x11d0673)
    #2 std::mutex::lock() /usr/include/c++/9/bits/std_mutex.h:100 (openttd+0x11d238a)
    #3 std::lock_guard<std::mutex>::lock_guard(std::mutex&) /usr/include/c++/9/bits/std_mutex.h:159 (openttd+0x11d63c8)
    #4 VideoDriver::Tick() /home/jgr/openttd/trunk/src/video/video_driver.cpp:124 (openttd+0x16ba75b)
    #5 VideoDriver_SDL_Base::LoopOnce() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:619 (openttd+0x16aafb6)
    #6 VideoDriver_SDL_Base::MainLoop() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:637 (openttd+0x16ab033)
    #7 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:815 (openttd+0x1b8b5b9)
    #8 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488e15)

  Mutex M1017 (0x7b6800000038) created at:
    #0 pthread_mutex_lock ../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:4165 (libtsan.so.0+0x526fc)
    #1 __gthread_mutex_lock /usr/include/x86_64-linux-gnu/c++/9/bits/gthr-default.h:749 (openttd+0x11d0673)
    #2 std::mutex::lock() /usr/include/c++/9/bits/std_mutex.h:100 (openttd+0x11d238a)
    #3 std::lock_guard<std::mutex>::lock_guard(std::mutex&) /usr/include/c++/9/bits/std_mutex.h:159 (openttd+0x11d63c8)
    #4 VideoDriver::Tick() /home/jgr/openttd/trunk/src/video/video_driver.cpp:125 (openttd+0x16ba772)
    #5 VideoDriver_SDL_Base::LoopOnce() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:619 (openttd+0x16aafb6)
    #6 VideoDriver_SDL_Base::MainLoop() /home/jgr/openttd/trunk/src/video/sdl2_v.cpp:637 (openttd+0x16ab033)
    #7 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:815 (openttd+0x1b8b5b9)
    #8 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488e15)

  Mutex M940 (0x7b0c0000d980) created at:
    #0 pthread_mutex_init ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:1220 (libtsan.so.0+0x4a616)
    #1 <null> <null> (libSDL2-2.0.so.0+0xee6e6)
    #2 DriverFactoryBase::SelectDriverImpl(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:122 (openttd+0x17e587e)
    #3 DriverFactoryBase::SelectDriver(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:87 (openttd+0x17e5400)
    #4 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:802 (openttd+0x1b8b4e5)
    #5 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488e15)

  Thread T2 'SDLAudioP2' (tid=734890, running) created by main thread at:
    #0 pthread_create ../../../../src/libsanitizer/tsan/tsan_interceptors_posix.cpp:962 (libtsan.so.0+0x5ea79)
    #1 <null> <null> (libSDL2-2.0.so.0+0xee1ba)
    #2 DriverFactoryBase::SelectDriverImpl(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:122 (openttd+0x17e587e)
    #3 DriverFactoryBase::SelectDriver(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Driver::Type) /home/jgr/openttd/trunk/src/driver.cpp:87 (openttd+0x17e5400)
    #4 openttd_main(int, char**) /home/jgr/openttd/trunk/src/openttd.cpp:802 (openttd+0x1b8b4e5)
    #5 main /home/jgr/openttd/trunk/src/os/unix/unix.cpp:262 (openttd+0x1488e15)

SUMMARY: ThreadSanitizer: data race /home/jgr/openttd/trunk/src/framerate_gui.cpp:552 in FramerateWindow::UpdateWidgetSize(int, Dimension*, Dimension const&, Dimension*, Dimension*)
==================

Description

Use a std::atomic for mixer channel active states, with proper ordering semantic so that the MixerChannel access is thread-safe.
Use a std::atomic for the effect volume (in a similar way to how music volume is handled).
Store PFE_SOUND measurements into a mutex-protected buffer which is then drained by the main thread.

Limitations

N/A

Checklist for review

Some things are not automated, and forgotten often. This list is a reminder for the reviewers.

The bug fix is important enough to be backported? (label: 'backport requested')
This PR touches english.txt or translations? Check the guidelines
This PR affects the save game format? (label 'savegame upgrade')
This PR affects the GS/AI API? (label 'needs review: Script API')
- ai_changelog.hpp, gs_changelog.hpp need updating.
- The compatibility wrappers (compat_*.nut) need updating.
This PR affects the NewGRF API? (label 'needs review: NewGRF')
- newgrf_debug_data.h may need updating.
- PR must be added to API tracker

LordAro · 2022-11-10T09:05:55Z

src/framerate_gui.cpp

@@ -1079,3 +1096,15 @@ void ConPrintFramerate()
 		IConsolePrint(CC_ERROR, "No performance measurements have been taken yet.");
 	}
 }
+
+void ProcessPendingPerformanceMeasurements()


would be good to have some comments explaining why only the sound performance stuff is ever "pending"

I've added some explanatory text

src/mixer.cpp

JGRennison force-pushed the fix-sound-mixer-data-races branch from ec02451 to 7978194 Compare November 10, 2022 00:47

LordAro reviewed Nov 10, 2022

View reviewed changes

michicc reviewed Nov 10, 2022

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src/mixer.cpp Show resolved Hide resolved

JGRennison added 3 commits November 10, 2022 21:17

Fix: Data races on MixerChannel active states

d13f299

Fix: Data race on effect volume setting with mixer thread

13a5228

Fix: Data race with mixer thread performance measurements

c358c7f

JGRennison force-pushed the fix-sound-mixer-data-races branch from 7978194 to c358c7f Compare November 10, 2022 21:17

michicc approved these changes Nov 10, 2022

View reviewed changes

michicc merged commit 64b437f into OpenTTD:master Nov 11, 2022

PeterN added a commit to PeterN/OpenTTD that referenced this pull request Dec 10, 2022

Fix OpenTTD#10147: Sound effect volume slider no longer set volume.

6c488da

PeterN mentioned this pull request Dec 10, 2022

Fix #10147: Sound effect volume slider no longer set volume. #10228

Merged

PeterN added a commit that referenced this pull request Dec 10, 2022

Fix #10147: Sound effect volume slider no longer set volume. (#10228)

daacde4

JGRennison deleted the fix-sound-mixer-data-races branch January 9, 2024 19:20

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Fix thread safety/data races between game and sound effect mixer threads #10147

Fix thread safety/data races between game and sound effect mixer threads #10147

JGRennison commented Nov 7, 2022 •

edited

LordAro Nov 10, 2022

JGRennison Nov 10, 2022

Fix thread safety/data races between game and sound effect mixer threads #10147

Fix thread safety/data races between game and sound effect mixer threads #10147

Conversation

JGRennison commented Nov 7, 2022 • edited

Motivation / Problem

Description

Limitations

Checklist for review

LordAro Nov 10, 2022

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JGRennison commented Nov 7, 2022 •

edited