Hi Paolo, Thanks very much. And...(see below) On Tue, Dec 17, 2013 at 7:21 PM, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote: > Il 17/12/2013 07:11, Arthur Chunqi Li ha scritto: >> Hi Paolo, >> >> Since VCPU is managed the same as a process in kernel, how can I know >> the status (running, sleeping etc.) of a vcpu in kernel? Is there a >> variant in struct kvm_vcpu or something else indicate this? > > waitqueue_active(&vcpu->wq) means that the VCPU is sleeping in the > kernel (i.e. in a halted state). > > vcpu->mode == IN_GUEST_MODE means that the VCPU is running. > > Anything else means that the host is running some kind of "glue" code > (either kernel or userspace). Another question about scheduler. When I have 4 vcpus and the workload of VM is low, and I noticed that it tends to activate only 1 or 2 vcpus. Does this mean the other 2 vcpus are scheduled out or into sleeping status? > >> Besides, if vcpu1 is running on pcpu1, and a kernel thread running on >> pcpu0. Can the kernel thread send a message to force vcpu1 trap to >> VMM? How can I do this? > > Yes, with kvm_vcpu_kick. KVM tracks internally which pcpu will run the > vcpu in vcpu->cpu, and kvm_vcpu_kick sends either a wakeup (if the vcpu > is sleeping) or an IPI (if it is running). What is vcpu's action if kvm_vcpu_kick(vcpu)? What is the exit_reason of the kicked vcpu? > > Paolo > Besides, can I pin a vcpu to a pcpu? That is to say, I assigned a pcpu only for a vcpu and pcpu can only run this vcpu? Thanks, Arthur -- Arthur Chunqi Li Department of Computer Science School of EECS Peking University Beijing, China -- 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
