> which is hacky, but there's a rationale for it: > > (a) avoid the crazy long wait queues ;) > > (b) we know that migration is *supposed* to be CPU-bound (not IO > bound), so yielding the CPU and retrying may just be the right thing > to do.
So this would degenerate into a spin when the contention is with other CPUs? But then if we guarantee that migration has flat latency curve and no long tail it may be reasonable. If the contention is with the local CPU it could cause some unfairness (and in theory priority inheritance issues with local CPU contenders?), but hopefully not too bad. -Andi
