Re: [PATCH v2 8/9] qemu-kvm: Refresh MSI settings after vmload

["Michael S. Tsirkin" <mst@redhat.com>]

On Wed, Apr 27, 2011 at 04:39:53PM +0200, Jan Kiszka wrote:
> On 2011-04-27 16:30, Michael S. Tsirkin wrote:
> >>>> --- a/hw/pci.c
> >>>> +++ b/hw/pci.c
> >>>> @@ -34,6 +34,7 @@
> >>>>  #include "device-assignment.h"
> >>>>  #include "qemu-objects.h"
> >>>>  #include "range.h"
> >>>> +#include "msi.h"
> >>>>  
> >>>>  //#define DEBUG_PCI
> >>>>  #ifdef DEBUG_PCI
> >>>> @@ -342,6 +343,7 @@ static int get_pci_config_device(QEMUFile *f, void *pv, size_t size)
> >>>>      memcpy(s->config, config, size);
> >>>>  
> >>>>      pci_update_mappings(s);
> >>>> +    msi_post_load(s);
> >>>
> >>> Pls don't do this: I'm trying to keep just the core in
> >>> pci.c and all capabilities in separate files.
> >>> msix has msix_load, msi will just need one too,
> >>> and let all devices call that.
> >>>
> >>
> >> Preferred alternatives are...? Registering a vmstate for msi?
> >>
> >> Jan
> > 
> > Add msi_load and call that from devices that need it.
> > Like msix_load does now.
> > 
> 
> msix_load/save are refactoring candidates IMHO. MSI-X has a real need
> for storing additional state information, so it should register its own
> subsection.

That's an implementation detail though, isn't it.

> I don't want to offload this burden to the devices also for
> MSI.
> From the devices' POV, why shouldn't msi_init suffice?
> 
> Jan

One can also claim this about config writes:
    pci_bridge_write_config(d, address, val, len);
    pcie_cap_flr_write_config(d, address, val, len);
    pcie_cap_slot_write_config(d, address, val, len);
    msi_write_config(d, address, val, len);
    pcie_aer_write_config(d, address, val, len);
which arguably just duplicates the initialization sequence.

What I'm trying to do though is to keep it modular and
keep module inter-dependencies to a minimum,
so that pci is the core and msix depends on it
but not the other way around.

What I think we should do is to add a pci subdirectory, move all
of the stuff there, move pci.c to pci/core.c and
add a high level module that depends on them all
and deals with all the capabilities.

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