Re: Arch-neutral name for hardware interrupt support

["Roger Pau Monné" <roger.pau@citrix.com>]

On Wed, Nov 03, 2021 at 10:16:26AM +0000, Jane Malalane wrote:
> On 02/11/2021 08:51, Roger Pau Monné wrote:
> > On Mon, Nov 01, 2021 at 10:47:26AM +0000, Andrew Cooper wrote:
> > > Hello,
> > > 
> > > On ARM, the GIC is a hard prerequisite for VMs.
> > > 
> > > I can't remember what the state of RISCV is, but IIRC there is still
> > > some debate over how interrupts are expected to work under virt.
> > > 
> > > On x86, the story is very different.  PV have no hardware assistance,
> > > while HVM hardware assistance depends on hardware support.  Therefore we
> > > want to introduce a new CDF flag so we can control the setting per
> > > domain, rather than globally as it is done now.
> > > 
> > > This brings us to the question of what a suitable architecture name
> > > would be.
> > > 
> > > Hardware Virtual Interrupts is a little too close to Hardware Virtual
> > > (Machine) Introspection, and Hardware Assisted Interrupts (mirroring
> > > HAP) doesn't seem great either.
> > > 
> > > Thoughts / ideas / suggestions?
> > Is this going to cover both hardware assisted interrupt
> > controller and assisted interrupt delivery (ie: APIC virtualization
> > and posted interrupts in x86 speak) or just one of them?
> > 
> > Thanks, Roger.
> 
> It's not going to cover IOMMU posted interrupts, only CPU posted interrupts.

IMO it needs to be something like Hardware {assisted,virtual}
interrupt controller, or some such, to differentiate from IOMMU posted
interrupts, which will likely use Hardware {assisted,virtual}
interrupts. So:

 * Hardware {assisted,virtual} interrupt controller: all APIC related
   hardware assisted emulation.
 * Hardware {assisted,virtual} interrupts: IOMMU posted interrupts.

I prefer `assisted` rather than `virtual`, but I'm not a native
speaker so my taste could go against what most prefer.

Regards, Roger.