Force SDL to use Kernel Semaphores on Windows.
Defined in SDL_hints.h
#define SDL_HINT_WINDOWS_FORCE_SEMAPHORE_KERNEL "SDL_WINDOWS_FORCE_SEMAPHORE_KERNEL"
Kernel Semaphores are inter-process and require a context switch on every interaction. On Windows 8 and newer, the WaitOnAddress API is available. Using that and atomics to implement semaphores increases performance. SDL will fall back to Kernel Objects on older OS versions or if forced to by this hint.
This variable can be set to the following values: