On Tue, Dec 4, 2018 at 6:36 AM Don Brace <don.brace@xxxxxxxxxxxxx> wrote:
>
> The PCI_IRQ_AFFINITY flag prevents customers from
> changing the smp_affinity and smp_affinity_list entries.
>
> - add a module parameter to allow this flag to be turned
> off.
>
> - to turn off PCI_IRQ_AFFINITY:
> flag hpsa_disable_irq_affinity=1
>
> Reviewed-by: David Carroll <david.carroll@xxxxxxxxxxxxx>
> Reviewed-by: Scott Teel <scott.teel@xxxxxxxxxxxxx>
> Signed-off-by: Don Brace <don.brace@xxxxxxxxxxxxx>
> ---
> drivers/scsi/hpsa.c | 13 ++++++++++---
> 1 file changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c
> index c9cccf35e9d7..0aa5aa66151f 100644
> --- a/drivers/scsi/hpsa.c
> +++ b/drivers/scsi/hpsa.c
> @@ -87,6 +87,10 @@ static int hpsa_simple_mode;
> module_param(hpsa_simple_mode, int, S_IRUGO|S_IWUSR);
> MODULE_PARM_DESC(hpsa_simple_mode,
> "Use 'simple mode' rather than 'performant mode'");
> +static bool hpsa_disable_irq_affinity;
> +module_param(hpsa_disable_irq_affinity, bool, S_IRUGO|S_IWUSR);
> +MODULE_PARM_DESC(hpsa_disable_irq_affinity,
> + "Turn off managed irq affinity. Allows smp_affinity to be changed.");
>
> /* define the PCI info for the cards we can control */
> static const struct pci_device_id hpsa_pci_device_id[] = {
> @@ -7389,7 +7393,7 @@ static void hpsa_setup_reply_map(struct ctlr_info *h)
> */
> static int hpsa_interrupt_mode(struct ctlr_info *h)
> {
> - unsigned int flags = PCI_IRQ_LEGACY;
> + unsigned int flags;
> int ret;
>
> /* Some boards advertise MSI but don't really support it */
> @@ -7400,17 +7404,20 @@ static int hpsa_interrupt_mode(struct ctlr_info *h)
> case 0x40830E11:
> break;
> default:
> + flags = PCI_IRQ_MSIX;
> + if (!hpsa_disable_irq_affinity)
> + flags |= PCI_IRQ_AFFINITY;
> ret = pci_alloc_irq_vectors(h->pdev, 1, MAX_REPLY_QUEUES,
> - PCI_IRQ_MSIX | PCI_IRQ_AFFINITY);
> + flags);
> if (ret > 0) {
> h->msix_vectors = ret;
> return 0;
> }
>
> - flags |= PCI_IRQ_MSI;
> break;
> }
>
> + flags = PCI_IRQ_LEGACY | PCI_IRQ_MSI;
> ret = pci_alloc_irq_vectors(h->pdev, 1, 1, flags);
> if (ret < 0)
> return ret;
>
This way may break blk-mq's queue mapping, especially might cause
issue in case of
CPU hotplug.
Thanks,
Ming Lei
