Re: [PATCH v2 06/12] iommu/vt-d: Acquiring lock in domain ID allocation helpers

[Baolu Lu]

On 2022/6/14 14:52, Tian, Kevin wrote:
> > From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> > Sent: Tuesday, June 14, 2022 10:52 AM
> >
> > The iommu->lock is used to protect the per-IOMMU domain ID resource.
> > Moving the lock into the ID alloc/free helpers makes the code more
> > compact. At the same time, the device_domain_lock is irrelevant to
> > the domain ID resource, remove its assertion as well.
> >
> > On the other hand, the iommu->lock is never used in interrupt context,
> > there's no need to use the irqsave variant of the spinlock calls.
>
> I still prefer to separating reduction of lock ranges from changing irqsave.
> Locking is tricky. From bisect p.o.v. it will be a lot easier if we just change
> one logic in one patch.

Fair enough. I will do this in the next version.

Best regards,
baolu