Re: [PATCH V7 4/5] virtio-scsi: introduce multiqueue support

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

 



Il 25/03/2013 08:25, Bart Van Assche ha scritto:
>>
>> +        queue_num = smp_processor_id();
>> +        while (unlikely(queue_num >= vscsi->num_queues))
>> +            queue_num -= vscsi->num_queues;
>> +
>> +        tgt->req_vq = vq = &vscsi->req_vqs[queue_num];
>> +    }
>> +
>> +    spin_unlock_irqrestore(&tgt->tgt_lock, flags);
>> +    return vq;
>> +}
> 
> Is there any reason why the smp_processor_id() % vscsi->num_queues
> computation in virtscsi_pick_vq() has been implemented as a loop instead
> of as an arithmetic operation ? If so, I would appreciate it if that
> could be explained in a comment.

The expectation is that vscsi->num_queues is the same as the number of
CPUs in the virtual machine; see patch 5 too.

Paolo
--
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