x86/apic: Convert to IRQCHIP_MOVE_DEFERRED

Instead of marking individual interrupts as safe to be migrated in
arbitrary contexts, mark the interrupt chips, which require the interrupt
to be moved in actual interrupt context, with the new IRQCHIP_MOVE_DEFERRED
flag. This makes more sense because this is a per interrupt chip property
and not restricted to individual interrupts.

That flips the logic from the historical opt-out to a opt-in model. This is
simpler to handle for other architectures, which default to unrestricted
affinity setting. It also allows to cleanup the redundant core logic
significantly.

All interrupt chips, which belong to a top-level domain sitting directly on
top of the x86 vector domain are marked accordingly, unless the related
setup code marks the interrupts with IRQ_MOVE_PCNTXT, i.e. XEN.

No functional change intended.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Steve Wahl <steve.wahl@hpe.com>
Acked-by: Wei Liu <wei.liu@kernel.org>
Link: https://lore.kernel.org/all/20241210103335.563277044@linutronix.de

5 files changed, 2 insertions, 9 deletions

diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index 0e0a531042ac..614f216215ea 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -2332,7 +2332,7 @@ static struct irq_chip intcapxt_controller = {
 	.irq_retrigger		= irq_chip_retrigger_hierarchy,
 	.irq_set_affinity       = intcapxt_set_affinity,
 	.irq_set_wake		= intcapxt_set_wake,
-	.flags			= IRQCHIP_MASK_ON_SUSPEND,
+	.flags			= IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_MOVE_DEFERRED,
 };
 
 static const struct irq_domain_ops intcapxt_domain_ops = {
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 3f691e1fd22c..b02e63124961 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -3532,7 +3532,6 @@ static int irq_remapping_alloc(struct irq_domain *domain, unsigned int virq,
 		irq_data->chip_data = data;
 		irq_data->chip = &amd_ir_chip;
 		irq_remapping_prepare_irte(data, cfg, info, devid, index, i);
-		irq_set_status_flags(virq + i, IRQ_MOVE_PCNTXT);
 	}
 
 	return 0;
diff --git a/drivers/iommu/intel/irq_remapping.c b/drivers/iommu/intel/irq_remapping.c
index 466c1412dd45..f5402df72a9b 100644
--- a/drivers/iommu/intel/irq_remapping.c
+++ b/drivers/iommu/intel/irq_remapping.c
@@ -1463,7 +1463,6 @@ static int intel_irq_remapping_alloc(struct irq_domain *domain,
 		else
 			irq_data->chip = &intel_ir_chip;
 		intel_irq_remapping_prepare_irte(ird, irq_cfg, info, index, i);
-		irq_set_status_flags(virq + i, IRQ_MOVE_PCNTXT);
 	}
 	return 0;
 
diff --git a/drivers/pci/controller/pci-hyperv.c b/drivers/pci/controller/pci-hyperv.c
index cdd5be16021d..6084b38bdda1 100644
--- a/drivers/pci/controller/pci-hyperv.c
+++ b/drivers/pci/controller/pci-hyperv.c
@@ -2053,6 +2053,7 @@ static struct irq_chip hv_msi_irq_chip = {
 	.irq_set_affinity	= irq_chip_set_affinity_parent,
 #ifdef CONFIG_X86
 	.irq_ack		= irq_chip_ack_parent,
+	.flags			= IRQCHIP_MOVE_DEFERRED,
 #elif defined(CONFIG_ARM64)
 	.irq_eoi		= irq_chip_eoi_parent,
 #endif
diff --git a/drivers/xen/events/events_base.c b/drivers/xen/events/events_base.c
index 985e155ebe4b..41309d38f78c 100644
--- a/drivers/xen/events/events_base.c
+++ b/drivers/xen/events/events_base.c
@@ -722,12 +722,6 @@ static struct irq_info *xen_irq_init(unsigned int irq)
 		INIT_RCU_WORK(&info->rwork, delayed_free_irq);
 
 		set_info_for_irq(irq, info);
-		/*
-		 * Interrupt affinity setting can be immediate. No point
-		 * in delaying it until an interrupt is handled.
-		 */
-		irq_set_status_flags(irq, IRQ_MOVE_PCNTXT);
-
 		INIT_LIST_HEAD(&info->eoi_list);
 		list_add_tail(&info->list, &xen_irq_list_head);
 	}