[PATCH v3 13/14] net/mlx5: Use irq_set_affinity_and_hint

From: Nitesh Narayan Lal
Date: Tue Jul 13 2021 - 17:17:17 EST


The driver uses irq_set_affinity_hint() to update the affinity_hint mask
that is consumed by the userspace to distribute the interrupts and to apply
the provided mask as the affinity for the mlx5 interrupts. However,
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_set_affinity_and_hint()
where the provided mask needs to be applied as the affinity and
affinity_hint pointer needs to be set and replace with
irq_update_affinity_hint() where only affinity_hint needs to be updated.

Signed-off-by: Nitesh Narayan Lal <nitesh@xxxxxxxxxx>
---
drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c b/drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c
index b25f764daa08..4efa3f643b79 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c
@@ -144,11 +144,11 @@ static void irq_release(struct kref *kref)
struct mlx5_irq_pool *pool = irq->pool;

xa_erase(&pool->irqs, irq->index);
- /* free_irq requires that affinity and rmap will be cleared
+ /* free_irq requires that affinity_hint and rmap will be cleared
* before calling it. This is why there is asymmetry with set_rmap
* which should be called after alloc_irq but before request_irq.
*/
- irq_set_affinity_hint(irq->irqn, NULL);
+ irq_update_affinity_hint(irq->irqn, NULL);
free_cpumask_var(irq->mask);
free_irq(irq->irqn, &irq->nh);
kfree(irq);
@@ -283,7 +283,7 @@ static struct mlx5_irq *irq_pool_create_irq(struct mlx5_irq_pool *pool,
if (IS_ERR(irq))
return irq;
cpumask_copy(irq->mask, affinity);
- irq_set_affinity_hint(irq->irqn, irq->mask);
+ irq_set_affinity_and_hint(irq->irqn, irq->mask);
return irq;
}

@@ -364,7 +364,7 @@ irq_pool_request_vector(struct mlx5_irq_pool *pool, int vecidx,
if (IS_ERR(irq) || !affinity)
goto unlock;
cpumask_copy(irq->mask, affinity);
- irq_set_affinity_hint(irq->irqn, irq->mask);
+ irq_set_affinity_and_hint(irq->irqn, irq->mask);
unlock:
mutex_unlock(&pool->lock);
return irq;
--
2.27.0