dolphin/Source/Core/InputCommon/ControllerEmu
Filoppi 1badceb455 ControllerInterface: fix UpdateReferences() deadlock
Removed useless locks to DeviceContainer::m_devices_mutex, as they were all already protected by m_devices_population_mutex.
We have no interest in blocking other threads that were potentially reading devices at the same time so this seems fine.
This simplifies the code, and I've adjusted a few comments which mentioned possible deadlock that should now be totally gone.

The deadlock could have happen if a thread directly called EmulatedController::UpdateReferences(), while another another thread also reached EmulatedController::UpdateReferences() within a call to ControllerInterface::UpdateDevices(), as the mentioned function locked both the DeviceContainer::m_devices_mutex and s_get_state_mutex at the same time.

The deadlock was frequent on game emulation startup on Android, due to the UpdateReferences() call in InputConfig::LoadConfig() and the UI thread triggering calls to ControllerInterface::UpdateDevices().
It could also have happened on Desktop if a user pressed "Refresh Devices" manually in the UI while the input config was loading.

Also brought some UpdateReferences() comments and thread safety fixes from https://github.com/dolphin-emu/dolphin/pull/9489
2021-11-20 16:54:36 +02:00
..
Control treewide: convert GPLv2+ license info to SPDX tags 2021-07-05 04:35:56 +02:00
ControlGroup treewide: convert GPLv2+ license info to SPDX tags 2021-07-05 04:35:56 +02:00
Setting treewide: convert GPLv2+ license info to SPDX tags 2021-07-05 04:35:56 +02:00
ControllerEmu.cpp ControllerInterface: fix UpdateReferences() deadlock 2021-11-20 16:54:36 +02:00
ControllerEmu.h treewide: convert GPLv2+ license info to SPDX tags 2021-07-05 04:35:56 +02:00
StickGate.cpp treewide: convert GPLv2+ license info to SPDX tags 2021-07-05 04:35:56 +02:00
StickGate.h treewide: convert GPLv2+ license info to SPDX tags 2021-07-05 04:35:56 +02:00