Re: Difference between vcpu_load and kvm_sched_in ?

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Paolo Bonzini <pbonzini <at> redhat.com> writes:

> 
> 
> On 21/10/2015 12:17, Hebbal Yacine wrote:
> > Thanks for the explanation, it's very clear.
> > I tired that but I didn't succeed to send the ioctl from "run_on_cpu"
> > function, I didn't find how to set the right CPUStat
> > I've tried "current_cpu"
> 
> Current_cpu is always NULL outside the VCPU thread.
> 
> > 
> > kvm_main.c:
> > 
> > // yacine.begin
> > 
> > static void do_vmi_start_kvm_ioctl(void *type) {
> >     printf("do_vmi_start_kvm_ioctl\n");
> >     kvm_vm_ioctl(kvm_state, type);


//yacine.begin
int hmp_vmi_op_result = 0;

static void do_vmi_kvm_ioctl(void *type_ioctl) {
    int* type = (int*) type_ioctl;
    hmp_vmi_op_result = kvm_vcpu_ioctl(current_cpu, *type);
    //hmp_vmi_start_result = kvm_vm_ioctl(kvm_state, *type);
}

int vmi_kvm_ioctl(int type) {
    CPUState* cpu;

    CPU_FOREACH(cpu) {
        run_on_cpu(cpu, do_vmi_kvm_ioctl, &type);
    }
    return hmp_vmi_op_result;
}
//yacine.end

Yes, it works perfectly this way even when running multiple VCPUs, thank you
a lot :)
In fact, I was using an old version of qemu (1.5.x), and it doesn't have
CPU_FOREACH, i searched a little for to replace it, but without any luck. So
I upgraded my working version and now everything is cool 

> Are you sure you want a VM ioctl and not a VCPU ioctl?  Or perhaps a VM
> ioctl to do generic processing, and a VCPU ioctl that is then sent to
> all VCPUs?
>If you use a VCPU ioctl, you can use CPU_FOREACH or a for loop to
> iterate over all VCPUs.

In fact, I get the same result when using vm_ioctl or vcpu_ioctl.
If I correctly understood you last paragraph, it is better to use vm_ioctl
to do generic processing that doesn't rely on a given VCPU and hence I won't
need to use "CPU_FOREACH, run_on_cpu and current_cpu".

Thanks again :)

> 
> Paolo
> --
> To unsubscribe from this list: send the line "unsubscribe kvm" in
> the body of a message to majordomo <at> vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 
> 




--
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



[Index of Archives]     [KVM ARM]     [KVM ia64]     [KVM ppc]     [Virtualization Tools]     [Spice Development]     [Libvirt]     [Libvirt Users]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite Questions]     [Linux Kernel]     [Linux SCSI]     [XFree86]
  Powered by Linux