net/mlx5: Introduce mlx5_cpumask_default_spread

For better code readability in the completion IRQ request code, define
the cpu lookup per completion vector logic in a separate function.

The new method mlx5_cpumask_default_spread() given a vector index 'n'
will return the 'nth' cpu. This new method will be used also in the next
patch.
Signed-off-by: Maher Sanalla <msanalla@nvidia.com>
Reviewed-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Moshe Shemesh <moshe@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

drivers/net/ethernet/mellanox/mlx5/core/eq.c

@@ -826,20 +826,18 @@ static void comp_irq_release_pci(struct mlx5_core_dev *dev, u16 vecidx)
 	mlx5_irq_release_vector(irq);
 }
 
-static int comp_irq_request_pci(struct mlx5_core_dev *dev, u16 vecidx)
+static int mlx5_cpumask_default_spread(int numa_node, int index)
 {
-	struct mlx5_eq_table *table = dev->priv.eq_table;
 	const struct cpumask *prev = cpu_none_mask;
 	const struct cpumask *mask;
-	struct mlx5_irq *irq;
 	int found_cpu = 0;
 	int i = 0;
 	int cpu;
 
 	rcu_read_lock();
-	for_each_numa_hop_mask(mask, dev->priv.numa_node) {
+	for_each_numa_hop_mask(mask, numa_node) {
 		for_each_cpu_andnot(cpu, mask, prev) {
-			if (i++ == vecidx) {
+			if (i++ == index) {
 				found_cpu = cpu;
 				goto spread_done;
 			}
@@ -849,7 +847,17 @@ static int comp_irq_request_pci(struct mlx5_core_dev *dev, u16 vecidx)
 
 spread_done:
 	rcu_read_unlock();
-	irq = mlx5_irq_request_vector(dev, found_cpu, vecidx, &table->rmap);
+	return found_cpu;
+}
+
+static int comp_irq_request_pci(struct mlx5_core_dev *dev, u16 vecidx)
+{
+	struct mlx5_eq_table *table = dev->priv.eq_table;
+	struct mlx5_irq *irq;
+	int cpu;
+
+	cpu = mlx5_cpumask_default_spread(dev->priv.numa_node, vecidx);
+	irq = mlx5_irq_request_vector(dev, cpu, vecidx, &table->rmap);
 	if (IS_ERR(irq))
 		return PTR_ERR(irq);