On 11/02/2017 02:08 PM, Eduardo Valentin wrote: > On Thu, Nov 02, 2017 at 06:56:46PM +0100, Paolo Bonzini wrote: >> On 02/11/2017 18:45, Eduardo Valentin wrote: >>> Currently, the existing qspinlock implementation will fallback to >>> test-and-set if the hypervisor has not set the PV_UNHALT flag. >>> >>> This patch gives the opportunity to guest kernels to select >>> between test-and-set and the regular queueu fair lock implementation >>> based on the PV_DEDICATED KVM feature flag. When the PV_DEDICATED >>> flag is not set, the code will still fall back to test-and-set, >>> but when the PV_DEDICATED flag is set, the code will use >>> the regular queue spinlock implementation. >> Have you seen Waiman's series that lets you specify this on the guest >> command line instead? Would this be acceptable for your use case? >> > No, can you please share a link to it? is it already merged to tip/master? See https://lkml.org/lkml/2017/11/1/655 Cheers, Longman
