Re: [RFC PATCH v2] PCI: hv: Avoid the retarget interrupt hypercall in irq_unmask() on ARM64

From: Lorenzo Pieralisi
Date: Wed Mar 02 2022 - 04:50:38 EST


On Wed, Mar 02, 2022 at 11:13:05AM +0800, Boqun Feng wrote:
> On Mon, Feb 21, 2022 at 05:56:00PM +0000, Wei Liu wrote:
> > On Thu, Feb 17, 2022 at 04:31:06PM +0000, Michael Kelley (LINUX) wrote:
> > > From: Boqun Feng <boqun.feng@xxxxxxxxx> Sent: Wednesday, February 16, 2022 7:45 PM
> > > >
> > > > On ARM64 Hyper-V guests, SPIs are used for the interrupts of virtual PCI
> > > > devices, and SPIs can be managed directly via GICD registers. Therefore
> > > > the retarget interrupt hypercall is not needed on ARM64.
> > > >
> > > > An arch-specific interface hv_arch_irq_unmask() is introduced to handle
> > > > the architecture level differences on this. For x86, the behavior
> > > > remains unchanged, while for ARM64 no hypercall is invoked when
> > > > unmasking an irq for virtual PCI devices.
> > > >
> > > > Signed-off-by: Boqun Feng <boqun.feng@xxxxxxxxx>
> > > > ---
> > > > v1 -> v2:
> > > >
> > > > * Introduce arch-specific interface hv_arch_irq_unmask() as
> > > > suggested by Bjorn
> > > >
> > > > drivers/pci/controller/pci-hyperv.c | 233 +++++++++++++++-------------
> > > > 1 file changed, 122 insertions(+), 111 deletions(-)
> > >
> > > Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
> >
> > I expect this to go through the PCI tree. Let me know if I should pick
> > this up.
> >
>
> I also expect the same.
>
> Lorenzo, let me know if there is more work needed for this patch.
> Thanks!

It is tagged as an RFC that's why I have not considered it for v5.18,
I will have a look shortly.

Thanks,
Lorenzo