On Thu, Jun 17, 2021 at 3:31 PM Robin Murphy [off-list ref] wrote:

On 2021-06-17 19:22, Nitesh Narayan Lal wrote:

quoted

The driver uses irq_set_affinity_hint() specifically for the high IOPS
queue interrupts 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

The driver enforces its own affinity to bind the high IOPS queue interrupts
to the local NUMA node. 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()
that clearly indicates the purpose of the usage and is meant to apply the
affinity and set the affinity_hint pointer. Also, replace
irq_set_affinity_hint() with irq_update_affinity_hint() when only
affinity_hint needs to be updated.

Change the megasas_set_high_iops_queue_affinity_hint function name to
megasas_set_high_iops_queue_affinity_and_hint to clearly indicate that the
function is setting both affinity and affinity_hint.

Signed-off-by: Nitesh Narayan Lal <redacted>
---
  drivers/scsi/megaraid/megaraid_sas_base.c | 25 ++++++++++++++---------
  1 file changed, 15 insertions(+), 10 deletions(-)

diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
index 4d4e9dbe5193..54f4eac09589 100644
--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c

@@ -5666,7 +5666,7 @@ megasas_setup_irqs_msix(struct megasas_instance *instance, u8 is_probe)
                              "Failed to register IRQ for vector %d.\n", i);
                      for (j = 0; j < i; j++) {
                              if (j < instance->low_latency_index_start)
-                                     irq_set_affinity_hint(
+                                     irq_update_affinity_hint(
                                              pci_irq_vector(pdev, j), NULL);
                              free_irq(pci_irq_vector(pdev, j),
                                       &instance->irq_context[j]);

@@ -5709,7 +5709,7 @@ megasas_destroy_irqs(struct megasas_instance *instance) {
      if (instance->msix_vectors)
              for (i = 0; i < instance->msix_vectors; i++) {
                      if (i < instance->low_latency_index_start)
-                             irq_set_affinity_hint(
+                             irq_update_affinity_hint(
                                  pci_irq_vector(instance->pdev, i), NULL);
                      free_irq(pci_irq_vector(instance->pdev, i),
                               &instance->irq_context[i]);

@@ -5840,22 +5840,27 @@ int megasas_get_device_list(struct megasas_instance *instance)
  }

  /**
- * megasas_set_high_iops_queue_affinity_hint -       Set affinity hint for high IOPS queues
- * @instance:                                        Adapter soft state
- * return:                                   void
+ * megasas_set_high_iops_queue_affinity_and_hint -   Set affinity and hint
+ *                                                   for high IOPS queues
+ * @instance:                                                Adapter soft state
+ * return:                                           void
   */
  static inline void
-megasas_set_high_iops_queue_affinity_hint(struct megasas_instance *instance)
+megasas_set_high_iops_queue_affinity_and_hint(struct megasas_instance *instance)
  {
      int i;
+     unsigned int irq;
      int local_numa_node;
+     const struct cpumask *mask;

      if (instance->perf_mode == MR_BALANCED_PERF_MODE) {
              local_numa_node = dev_to_node(&instance->pdev->dev);

Drive-by nit: you could assign mask in this scope.

Sure

quoted

-             for (i = 0; i < instance->low_latency_index_start; i++)
-                     irq_set_affinity_hint(pci_irq_vector(instance->pdev, i),
-                             cpumask_of_node(local_numa_node));
+             for (i = 0; i < instance->low_latency_index_start; i++) {
+                     irq = pci_irq_vector(instance->pdev, i);
+                     mask = cpumask_of_node(local_numa_node);
+                     irq_update_affinity_hint(irq, mask);

And this doesn't seem to match what the commit message says?

Clearly, thanks for catching it.
This should be irq_set_affinity_and_hint().

Robin.

quoted

+             }
      }
  }

@@ -5944,7 +5949,7 @@ megasas_alloc_irq_vectors(struct megasas_instance *instance)
              instance->msix_vectors = 0;

      if (instance->smp_affinity_enable)
-             megasas_set_high_iops_queue_affinity_hint(instance);
+             megasas_set_high_iops_queue_affinity_and_hint(instance);
  }

  /**

-- 
Thanks
Nitesh