Re: [RFC -v7 PATCH 0/7] directed yield for Pause Loop Exiting

2011-01-27 Thread Avi Kivity
On 01/26/2011 11:56 PM, Rik van Riel wrote: When running SMP virtual machines, it is possible for one VCPU to be spinning on a spinlock, while the VCPU that holds the spinlock is not currently running, because the host scheduler preempted it to run something else. Both Intel and AMD CPUs have a

[RFC -v7 PATCH 0/7] directed yield for Pause Loop Exiting

2011-01-26 Thread Rik van Riel
When running SMP virtual machines, it is possible for one VCPU to be spinning on a spinlock, while the VCPU that holds the spinlock is not currently running, because the host scheduler preempted it to run something else. Both Intel and AMD CPUs have a feature that detects when a virtual CPU is spi