net/mlx4: Use irq_update_affinity_hint()

The driver uses irq_set_affinity_hint() to update the affinity_hint mask
that is consumed by the userspace to distribute the interrupts. However,
under the hood irq_set_affinity_hint() also applies the provided cpumask
(if not NULL) as the affinity for the given interrupt which 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 updates the affinity_hint pointer.

Signed-off-by: Nitesh Narayan Lal <nitesh@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Link: https://lore.kernel.org/r/20210903152430.244937-15-nitesh@redhat.com

drivers/net/ethernet/mellanox/mlx4/eq.c

@@ -244,9 +244,9 @@ static void mlx4_set_eq_affinity_hint(struct mlx4_priv *priv, int vec)
 	    cpumask_empty(eq->affinity_mask))
 		return;
 
-	hint_err = irq_set_affinity_hint(eq->irq, eq->affinity_mask);
+	hint_err = irq_update_affinity_hint(eq->irq, eq->affinity_mask);
 	if (hint_err)
-		mlx4_warn(dev, "irq_set_affinity_hint failed, err %d\n", hint_err);
+		mlx4_warn(dev, "irq_update_affinity_hint failed, err %d\n", hint_err);
 }
 #endif
 
@@ -1123,9 +1123,7 @@ static void mlx4_free_irqs(struct mlx4_dev *dev)
 	for (i = 0; i < dev->caps.num_comp_vectors + 1; ++i)
 		if (eq_table->eq[i].have_irq) {
 			free_cpumask_var(eq_table->eq[i].affinity_mask);
-#if defined(CONFIG_SMP)
-			irq_set_affinity_hint(eq_table->eq[i].irq, NULL);
-#endif
+			irq_update_affinity_hint(eq_table->eq[i].irq, NULL);
 			free_irq(eq_table->eq[i].irq, eq_table->eq + i);
 			eq_table->eq[i].have_irq = 0;
 		}