Re: [Qemu-devel] [RFC PATCH v2 09/10] virtio-scsi-dataplane: Code to run virtio-scsi on iothread

[Fam Zheng]

On Fri, 09/19 11:29, Paolo Bonzini wrote:
> Il 06/08/2014 07:35, Fam Zheng ha scritto:
> > diff --git a/include/hw/virtio/virtio-scsi.h 
> > b/include/hw/virtio/virtio-scsi.h
> > index 6f92c29..b9f2197 100644
> > --- a/include/hw/virtio/virtio-scsi.h
> > +++ b/include/hw/virtio/virtio-scsi.h
> > @@ -174,6 +174,18 @@ typedef struct VirtIOSCSICommon {
> >      VirtQueue *ctrl_vq;
> >      VirtQueue *event_vq;
> >      VirtQueue **cmd_vqs;
> > +
> > +    /* Fields for dataplane below */
> > +    AioContext *ctx; /* one iothread per virtio-scsi-pci for now */
> > +
> > +    /* Vring is used instead of vq in dataplane code, because of the 
> > underlying
> > +     * memory layer thread safety */
> > +    VirtIOSCSIVring *ctrl_vring;
> > +    VirtIOSCSIVring *event_vring;
> > +    VirtIOSCSIVring **cmd_vrings;
> > +    bool dataplane_started;
> > +    bool dataplane_starting;
> > +    bool dataplane_stopping;
> 
> Please add these to VirtIOSCSI rather than VirtIOSCSICommon.  Same for
> the new functions you declare below.

What's the rationale, please? Asking because especially the VirtIOSCSIVring
fields are the dataplane counterparts of VirtQueue fields, so putting in
VirtIOSCSI seems unnatural for me.

Fam