Messages in this thread |  | | From | Thomas Gleixner <> | Subject | Re: About irq_create_affinity_masks() for a platform device driver | Date | Tue, 04 Feb 2020 09:20:02 +0000 |
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John,
John Garry <john.garry@huawei.com> writes: >> I wouldn't mind to expose a function which allows you to switch the >> allocated interrupts to managed. The reason why we do it in one go in >> the PCI code is that we get automatically the irq descriptors allocated >> on the correct node. So if the node aware allocation is not a >> showstopper > > I wouldn't say so for now.
Good.
> for this then your function would do: >> >> ... >> for (i = 0; i < count; i++) { >> pirqs[i] = platform_get_irq(dev, i); >> >> irq_update_affinity_desc(pirqs[i], affdescs + i); >> >> } >> >> int irq_update_affinity_desc(unsigned int irq, irq_affinity_desc *affinity) >> { >> unsigned long flags; >> struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0); >> >> if (!desc) >> return -EINVAL; >> >> if (affinity->is_managed) { >> irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED); >> irqd_set(&desc->irq_data, IRQD_IRQ_MASKED); > > Are these correct? I assume we want to follow alloc_descs() here.
Yeah, copied the wrong chunk :)
>> } >> cpumask_copy(desc->irq_common_data.affinity, affinity); >> return 0; >> } > > I see. So I made a couple of changes and it did work: > > int irq_update_affinity_desc(unsigned int irq, struct irq_affinity_desc > *affinity) > { > unsigned long flags; > struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0); > > if (!desc) > return -EINVAL; > > if (affinity->is_managed) { > irqd_set(&desc->irq_data, IRQD_AFFINITY_MANAGED); > irqd_set(&desc->irq_data, IRQD_MANAGED_SHUTDOWN); > } > > cpumask_copy(desc->irq_common_data.affinity, &affinity->mask); > irq_put_desc_unlock(desc, flags); > return 0; > }
Looks correct.
> And if we were to go this way, then we don't need to add the pointer in > struct platform_device to hold affinity mask descriptors as we're using > them immediately. Or even have a single function to do it all in the irq > code (create the masks and update the affinity desc). > > And since we're just updating the masks, I figure we shouldn't need to > add acpi_irq_get_count(), which I invented to get the irq count (without > creating the IRQ mapping).
Yes, you can create and apply the masks after setting up the interrupts.
Thanks,
tglx
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