On Fri, Aug 7, 2015 at 10:09 AM, Ian Romanick <i...@freedesktop.org> wrote: > I know we've talked about this about 100 times, but something in the > back of my mind tells me that we have a pre-existing race. What happens > if the p_atomic_dec_zero happens on thread A while thread B is between > the _mesa_lookup_renderbuffer call and the _mesa_reference_renderbuffer > call on the same object? Won't thread A free the memory out from under > thread B?
Generally: RefCount is initialized to 1 (in all cases but renderbuffers... that might be a bug -- did you choose renderbuffers in your example for this reason?). When Bind is called the first time, RefCount is incremented to 2. When Delete is called, RefCount is decremented -- RefCount only goes to 0 only if the object isn't bound anywhere, in which case it's actually deleted. If The object is still bound somewhere and RefCount is decremented to non-zero, the object cannot be rebound and will be deleted when its last reference is unbound. Commit 42aaa548 changed the renderbuffer code from RefCount = 1 to = 0. It seems pretty clearly wrong to me, since a glGenRenderbuffers()/glDeleteRenderBuffers() pair would fail to actually delete the renderbuffers. Does anyone else read it differently? _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev