[patch 54/55] x86/apic: Mark single target interrupts

[Thomas Gleixner]

If the interrupt destination mode of the APIC is physical then the
effective affinity is restricted to a single CPU.

Mark the interrupt accordingly in the domain allocation code, so the core
code can avoid pointless affinity setting attempts.

Signed-off-by: Thomas Gleixner <t...@linutronix.de>
---
 arch/x86/kernel/apic/vector.c |    7 +++++++
 1 file changed, 7 insertions(+)

--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -371,6 +371,13 @@ static int x86_vector_alloc_irqs(struct
                                               irq_data);
                if (err)
                        goto error;
+               /*
+                * If the apic destination mode is physical, then the
+                * effective affinity is restricted to a single target
+                * CPU. Mark the interrupt accordingly.
+                */
+               if (!apic->irq_dest_mode)
+                       irqd_set_single_target(irq_data);
        }
 
        return 0;