[Qemu-devel] Re: [PATCH 4/4] pci: interrupt disable bit support

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

On Thu, Nov 26, 2009 at 12:04:51PM +0900, Isaku Yamahata wrote:
> On Wed, Nov 25, 2009 at 06:59:06PM +0200, Michael S. Tsirkin wrote:
> > interrupt disable bit is mandatory in PCI spec,
> > so we must implement it to be spec compliant.
> > 
> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> > ---
> >  hw/pci.c |   57 ++++++++++++++++++++++++++++++++++++++++-----------------
> >  hw/pci.h |    4 ++++
> >  2 files changed, 44 insertions(+), 17 deletions(-)
> > 
> > diff --git a/hw/pci.c b/hw/pci.c
> > index 844664b..3daae46 100644
> > --- a/hw/pci.c
> > +++ b/hw/pci.c
> > @@ -114,12 +114,43 @@ static void pci_update_irq_status(PCIDevice *dev)
> >      }
> >  }
> >  
> > +static void pci_change_irq_level(PCIDevice *pci_dev, int irq_num, int change)
> > +{
> > +    PCIBus *bus;
> > +    for (;;) {
> > +        bus = pci_dev->bus;
> > +        irq_num = bus->map_irq(pci_dev, irq_num);
> > +        if (bus->set_irq)
> > +            break;
> > +        pci_dev = bus->parent_dev;
> > +    }
> > +    bus->irq_count[irq_num] += change;
> > +    bus->set_irq(bus->irq_opaque, irq_num, bus->irq_count[irq_num] != 0);
> 
> Let's use ! instead of != 0 for consistency.

By the way, this would have to be !!, not !.
So not sure there's much consistency to be gained:
!= appears in pci.c more times than !!.

-- 
MST