Re: [PATCH 05/10] iommu/amd: remove the special case from get_irq_table()

From: Sebastian Andrzej Siewior
Date: Thu Mar 15 2018 - 09:02:00 EST


On 2018-03-15 13:53:42 [+0100], Joerg Roedel wrote:
> On Fri, Feb 23, 2018 at 11:27:31PM +0100, Sebastian Andrzej Siewior wrote:
> > @@ -4103,10 +4093,26 @@ static int irq_remapping_alloc(struct irq_domain *domain, unsigned int virq,
> > return ret;
> >
> > if (info->type == X86_IRQ_ALLOC_TYPE_IOAPIC) {
> > - if (get_irq_table(devid, true))
> > + struct irq_remap_table *table;
> > + struct amd_iommu *iommu;
> > +
> > + table = get_irq_table(devid);
> > + if (table) {
> > + if (!table->min_index) {
> > + /*
> > + * Keep the first 32 indexes free for IOAPIC
> > + * interrupts.
> > + */
> > + table->min_index = 32;
> > + iommu = amd_iommu_rlookup_table[devid];
> > + for (i = 0; i < 32; ++i)
> > + iommu->irte_ops->set_allocated(table, i);
> > + }
>
> I think this needs to be protected by the table->lock.

Which part any why? The !->min_index part plus extending(setting to 32)?

Sebastian