iavf: Use irq_update_affinity_hint()

The driver uses irq_set_affinity_hint() for two purposes:

- To set the affinity_hint which is consumed by the userspace for
  distributing the interrupts

- To apply an affinity that it provides for the iavf interrupts

The latter is done to ensure that all the interrupts are evenly spread
across all available CPUs. However, since commit a0c9259 ("irq/matrix:
Spread interrupts on allocation") the spreading of interrupts is
dynamically performed at the time of allocation. Hence, there is no need
for the drivers to enforce their own affinity for the spreading of
interrupts.

Also, irq_set_affinity_hint() applying the provided cpumask as an affinity
for the interrupt is an undocumented side effect. To remove this side
effect irq_set_affinity_hint() has been marked as deprecated and new
interfaces have been introduced. Hence, replace the irq_set_affinity_hint()
with the new interface irq_update_affinity_hint() that only sets the
pointer for the affinity_hint.

Signed-off-by: Nitesh Narayan Lal <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Acked-by: Jesse Brandeburg <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: Nitesh Narayan Lal

drivers/net/ethernet/intel/iavf/iavf_main.c

@@ -492,10 +492,10 @@ iavf_request_traffic_irqs(struct iavf_adapter *adapter, char *basename)
 		irq_set_affinity_notifier(irq_num, &q_vector->affinity_notify);
 		/* Spread the IRQ affinity hints across online CPUs. Note that
 		 * get_cpu_mask returns a mask with a permanent lifetime so
-		 * it's safe to use as a hint for irq_set_affinity_hint.
+		 * it's safe to use as a hint for irq_update_affinity_hint.
 		 */
 		cpu = cpumask_local_spread(q_vector->v_idx, -1);
-		irq_set_affinity_hint(irq_num, get_cpu_mask(cpu));
+		irq_update_affinity_hint(irq_num, get_cpu_mask(cpu));
 	}
 
 	return 0;
@@ -505,7 +505,7 @@ iavf_request_traffic_irqs(struct iavf_adapter *adapter, char *basename)
 		vector--;
 		irq_num = adapter->msix_entries[vector + NONQ_VECS].vector;
 		irq_set_affinity_notifier(irq_num, NULL);
-		irq_set_affinity_hint(irq_num, NULL);
+		irq_update_affinity_hint(irq_num, NULL);
 		free_irq(irq_num, &adapter->q_vectors[vector]);
 	}
 	return err;
@@ -557,7 +557,7 @@ static void iavf_free_traffic_irqs(struct iavf_adapter *adapter)
 	for (vector = 0; vector < q_vectors; vector++) {
 		irq_num = adapter->msix_entries[vector + NONQ_VECS].vector;
 		irq_set_affinity_notifier(irq_num, NULL);
-		irq_set_affinity_hint(irq_num, NULL);
+		irq_update_affinity_hint(irq_num, NULL);
 		free_irq(irq_num, &adapter->q_vectors[vector]);
 	}
 }