On Mon, 9 Jun 2025 21:15:08 GMT, Kevin Rushforth <k...@openjdk.org> wrote:
> > Multi-threaded access in the sense of the not being used concurrently by > > different threads ? What FFM means is that the thread that creates the > > Arena is the only thread ever allowed to use the Arena or any memory > > allocated by it. I don't quite see how you guarantee a static field of a > > class is never accessed by another thread. And all it takes is for some > > other thread to have initialize the class and boom > > And how in fact is Marlin ensuring only one thread is ever used to run > > Marlin ? I didn't think it did anything of the kind. Is this just a case of > > the FX thread always runs it ? > > The QuantumRenderer thread uses Marlin during rendering and the JavaFX > application thread uses it during picking. > > @bourgesl can provide a more complete answer, but from what I see, all > accesses to OffHeapArray are done via an instance of the RendererContext > class. Marlin ensures that a RendererContext instance is created and accessed > on the same thread by using thread local state and using the rendering > context for the thread in question (or creating it if it is the first time). > See > [DMarlinRenderingEngine::getRendererContext](https://github.com/openjdk/jfx/blob/b22ed6d202f7bb3765fa402a748d455f6316f7c9/modules/javafx.graphics/src/main/java/com/sun/marlin/DMarlinRenderingEngine.java#L254). I'd looked at that but it was not obvious. And it definitely is not obvious that it will be the same thread that initialises the MaskMarlinAlphaConsumer.java class ------------- PR Comment: https://git.openjdk.org/jfx/pull/1814#issuecomment-2957070973
