Not a terribly helpful answer, but DisplayLink is not a good API for games to use. Display Link doesn't handle timing for multiple displays, it invokes the callback on a high priority thread which isn't meant to have a lot of work done on it, and makes it really easy to lock up the OS's entire display system. When I ran into similar issues a couple years ago, I asked an Apple OpenGL engineer about it. His reply was basically not to use CVDisplayLink for anything ever. Names aside, it's *very* different from CADisplayLink on iOS, operates very differently, and serves a much lower level purpose.
I know it's not terribly helpful to basically say, "don't use the thing that Cocos2D uses by default", but I don't have time to offer a code solution. Are there alternate CCDirector implementations to use on OS X that don't use it? Something that just relies on VBL sync is ideal. I've never done any CC2D/Mac stuff myself.