Re: [PATCH v2 09/17] migration/multifd: Device state transfer support - receive side

[Peter Xu <peterx@redhat.com>]

On Mon, Sep 02, 2024 at 10:12:01PM +0200, Maciej S. Szmigiero wrote:
> > > diff --git a/migration/multifd.h b/migration/multifd.h
> > > index a3e35196d179..a8f3e4838c01 100644
> > > --- a/migration/multifd.h
> > > +++ b/migration/multifd.h
> > > @@ -45,6 +45,12 @@ MultiFDRecvData *multifd_get_recv_data(void);
> > >   #define MULTIFD_FLAG_QPL (4 << 1)
> > >   #define MULTIFD_FLAG_UADK (8 << 1)
> > > +/*
> > > + * If set it means that this packet contains device state
> > > + * (MultiFDPacketDeviceState_t), not RAM data (MultiFDPacket_t).
> > > + */
> > > +#define MULTIFD_FLAG_DEVICE_STATE (1 << 4)
> > 
> > Overlaps with UADK. I assume on purpose because device_state doesn't
> > support compression? Might be worth a comment.
> > 
> 
> Yes, the device state transfer bit stream does not support compression
> so it is not a problem since these "compression type" flags will never
> be set in such bit stream anyway.
> 
> Will add a relevant comment here.

Why reuse?  Would using a new bit easier if we still have plenty of bits
(just to tell what is what directly from a stream dump)?

-- 
Peter Xu