x86/apic/vector: Ignore set_affinity call for inactive interrupts

The core interrupt code can call the affinity setter for inactive
interrupts under certain circumstances.

For inactive intererupts which use managed or reservation mode this is a
pointless exercise as the activation will assign a vector which fits the
destination mask.

Check for this and return w/o going through the vector assignment.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 13 insertions, 0 deletions

diff --git a/arch/x86/kernel/apic/vector.c b/arch/x86/kernel/apic/vector.c
index 6789e286def9..573538e0981e 100644
--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -726,8 +726,21 @@ void lapic_offline(void)
 static int apic_set_affinity(struct irq_data *irqd,
 			     const struct cpumask *dest, bool force)
 {
+	struct apic_chip_data *apicd = apic_chip_data(irqd);
 	int err;
 
+	/*
+	 * Core code can call here for inactive interrupts. For inactive
+	 * interrupts which use managed or reservation mode there is no
+	 * point in going through the vector assignment right now as the
+	 * activation will assign a vector which fits the destination
+	 * cpumask. Let the core code store the destination mask and be
+	 * done with it.
+	 */
+	if (!irqd_is_activated(irqd) &&
+	    (apicd->is_managed || apicd->can_reserve))
+		return IRQ_SET_MASK_OK;
+
 	raw_spin_lock(&vector_lock);
 	cpumask_and(vector_searchmask, dest, cpu_online_mask);
 	if (irqd_affinity_is_managed(irqd))