[PATCH] megaraid_sas: clear affinity hint

[PATCH] megaraid_sas: clear affinity hint

[Tomas Henzl]

Affinity hint should be cleared before freeing irq.

Signed-off-by: Tomas Henzl <thenzl@redhat.com>
---
 drivers/scsi/megaraid/megaraid_sas_base.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
index 00668335c..d5626ad8b 100644
--- a/drivers/scsi/megaraid/megaraid_sas_base.c
+++ b/drivers/scsi/megaraid/megaraid_sas_base.c
@@ -5602,9 +5602,11 @@ megasas_setup_irqs_msix(struct megasas_instance *instance, u8 is_probe)
 			&instance->irq_context[i])) {
 			dev_err(&instance->pdev->dev,
 				"Failed to register IRQ for vector %d.\n", i);
-			for (j = 0; j < i; j++)
+			for (j = 0; j < i; j++) {
+				irq_set_affinity_hint(pci_irq_vector(pdev, j), NULL);
 				free_irq(pci_irq_vector(pdev, j),
 					 &instance->irq_context[j]);
+			}
 			/* Retry irq register for IO_APIC*/
 			instance->msix_vectors = 0;
 			instance->msix_load_balance = false;
@@ -5642,6 +5644,7 @@ megasas_destroy_irqs(struct megasas_instance *instance) {
 
 	if (instance->msix_vectors)
 		for (i = 0; i < instance->msix_vectors; i++) {
+			irq_set_affinity_hint(pci_irq_vector(instance->pdev, i), NULL);
 			free_irq(pci_irq_vector(instance->pdev, i),
 				 &instance->irq_context[i]);
 		}
-- 
2.21.3

Re: [PATCH] megaraid_sas: clear affinity hint

[Sumit Saxena]

On Thu, Jun 25, 2020 at 10:42 PM Tomas Henzl <thenzl@redhat.com> wrote:
>
> Affinity hint should be cleared before freeing irq.
Hi Tomas,

megaraid_sas driver setups IRQ affinity(non-managed) for MSI-x index
"0" to "instance->low_latency_index_start - 1".
Rest of MSI-x indices- "instance->low_latency_index_start" to
"instance->msix_vectors -1" are managed (API- pci_alloc_irq_affinity()
takes care of this)
so calling irq_set_affinity_hint() for managed IRQs does not seem
right. Please try setting affinity to NULL for only this range- "0" to
 "instance->low_latency_index_start -1" and see if it solves your
problem.

Also, is it regression due to below commit:

f0b9e7bdc309 scsi: megaraid_sas: Set affinity for high IOPS reply queues

Thanks,
Sumit
>
> Signed-off-by: Tomas Henzl <thenzl@redhat.com>
> ---
>  drivers/scsi/megaraid/megaraid_sas_base.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/scsi/megaraid/megaraid_sas_base.c b/drivers/scsi/megaraid/megaraid_sas_base.c
> index 00668335c..d5626ad8b 100644
> --- a/drivers/scsi/megaraid/megaraid_sas_base.c
> +++ b/drivers/scsi/megaraid/megaraid_sas_base.c
> @@ -5602,9 +5602,11 @@ megasas_setup_irqs_msix(struct megasas_instance *instance, u8 is_probe)
>                         &instance->irq_context[i])) {
>                         dev_err(&instance->pdev->dev,
>                                 "Failed to register IRQ for vector %d.\n", i);
> -                       for (j = 0; j < i; j++)
> +                       for (j = 0; j < i; j++) {
> +                               irq_set_affinity_hint(pci_irq_vector(pdev, j), NULL);
>                                 free_irq(pci_irq_vector(pdev, j),
>                                          &instance->irq_context[j]);
> +                       }
>                         /* Retry irq register for IO_APIC*/
>                         instance->msix_vectors = 0;
>                         instance->msix_load_balance = false;
> @@ -5642,6 +5644,7 @@ megasas_destroy_irqs(struct megasas_instance *instance) {
>
>         if (instance->msix_vectors)
>                 for (i = 0; i < instance->msix_vectors; i++) {
> +                       irq_set_affinity_hint(pci_irq_vector(instance->pdev, i), NULL);
>                         free_irq(pci_irq_vector(instance->pdev, i),
>                                  &instance->irq_context[i]);
>                 }
> --
> 2.21.3
>