Re: [Xen-devel] [PATCH 09/10] log-dirty: Refine common code to support PML

[Tim Deegan <tim@xxxxxxx>]

At 15:38 +0800 on 10 Apr (1428680289), Kai Huang wrote:
> 
> 
> On 04/09/2015 08:27 PM, Tim Deegan wrote:
> > At 10:35 +0800 on 27 Mar (1427452553), Kai Huang wrote:
> >> --- a/xen/arch/x86/mm/paging.c
> >> +++ b/xen/arch/x86/mm/paging.c
> >> @@ -411,7 +411,18 @@ static int paging_log_dirty_op(struct domain *d,
> >>       int i4, i3, i2;
> >>   
> >>       if ( !resuming )
> >> +    {
> >>           domain_pause(d);
> >> +
> >> +        /*
> >> +         * Only need to flush when not resuming, as domain was paused in
> >> +         * resuming case therefore it's not possible to have any new dirty
> >> +         * page.
> >> +         */
> >> +        if ( d->arch.paging.log_dirty.flush_cached_dirty )
> >> +            d->arch.paging.log_dirty.flush_cached_dirty(d);
> > I think there are too many layers of indirection here. :)  How about:
> >   - don't add a flush_cached_dirty() function to the log_dirty ops.
> >   - just call p2m_flush_hardware_cached_dirty(d) here.
> >
> > Would that work OK?
> Thanks for pointing out.
> 
> Is it nature to call p2m layer functions in paging.c? If there's no 
> restriction on it, calling p2m_flush_hardware_cached_dirty is more 
> clear, and it should work.

Yes, calling public p2m functions directly is OK -- it's the internal
function pointers like ->get_entry() that aren't supposed to be called
from outside p2m code.  I guess that's not terribly clear - maybe it
needs some better comments.

Tim.

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel