On Tue, Feb 28, 2012 at 10:09 AM, Avi Kivity <avi@xxxxxxxxxx> wrote: > > This is done by preempt notifiers. Whenever a task switch happens we > push the guest fpu state into memory (if loaded) and let the normal > stuff happen. So the if we had a task switch during instruction > emulation, for example, then we'd get the "glacial and stupid path" to fire. Oh christ. This is exactly what the scheduler has ALWAYS ALREADY DONE FOR YOU. That's what the i387 save-and-restore code is all about. What's the advantage of just re-implementing it in non-obvious ways? Stop doing it. You get *zero* advantages from just doing what the scheduler natively does for you, and the scheduler does it *better*. Linus -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html