Hello Dan,
On Thu, 2017-11-23 at 13:44 +0300, Dan Carpenter wrote:
> On Thu, Nov 23, 2017 at 09:27:19AM +0800, Ching Huang wrote:
> > From: Ching Huang <ching2...@areca.com.tw>
> >
> > Add module parameter msi_enable to has a chance to disable msi interrupt if
> > it does not work properly.
> >
> > Signed-off-by: Ching Huang <ching2...@areca.com.tw>
> > ---
> >
> > diff -uprN a/drivers/scsi/arcmsr/arcmsr_hba.c
> > b/drivers/scsi/arcmsr/arcmsr_hba.c
> > --- a/drivers/scsi/arcmsr/arcmsr_hba.c 2017-11-23 14:29:26.000000000
> > +0800
> > +++ b/drivers/scsi/arcmsr/arcmsr_hba.c 2017-11-23 16:02:28.000000000
> > +0800
> > @@ -75,6 +75,10 @@ MODULE_DESCRIPTION("Areca ARC11xx/12xx/1
> > MODULE_LICENSE("Dual BSD/GPL");
> > MODULE_VERSION(ARCMSR_DRIVER_VERSION);
> >
> > +static int msi_enable = 1;
> > +module_param(msi_enable, int, S_IRUGO);
> ^^^^^^^
> checkpatch.pl will complain that this should be 0444
S_IRUGO value is 00444, defined in <linux/stat.h> -> <uapi/linux/stat.h>.
A. It will be not a issue.
>
> > +MODULE_PARM_DESC(msi_enable, " Enable MSI interrupt(0 ~ 1),
> > msi_enable=1(enable), =0(disable)");
> ^
> Remove the extra space
OK
>
> > +
> > static int host_can_queue = ARCMSR_DEFAULT_OUTSTANDING_CMD;
> > module_param(host_can_queue, int, S_IRUGO);
> > MODULE_PARM_DESC(host_can_queue, " adapter queue depth(32 ~ 1024), default
> > is 128");
> > @@ -831,11 +835,15 @@ arcmsr_request_irq(struct pci_dev *pdev,
> > pr_info("arcmsr%d: msi-x enabled\n", acb->host->host_no);
> > flags = 0;
> > } else {
> > - nvec = pci_alloc_irq_vectors(pdev, 1, 1,
> > - PCI_IRQ_MSI | PCI_IRQ_LEGACY);
> > + if (msi_enable == 1)
> > + nvec = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSI);
> > + else
> > + nvec = pci_alloc_irq_vectors(pdev, 1, 1,
> > PCI_IRQ_LEGACY);
> > if (nvec < 1)
> > return FAILED;
>
> I feel like we should try PCI_IRQ_MSI then if it fails we could fall
> back to PCI_IRQ_LEGACY. Originally, it worked like this and now it just
> fails unless you toggle the module param. It's a regression.
update as below
---
unsigned int irq_flag;
irq_flag = PCI_IRQ_LEGACY;
if (msi_enable == 1)
irq_flag |= PCI_IRQ_MSI;
nvec = pci_alloc_irq_vectors(pdev, 1, 1, irq_flag);
> >
> > + if (msi_enable == 1)
> > + pr_info("arcmsr%d: msi enabled\n", acb->host->host_no);
>
> This printk could be improved. Use dev_info(&pdev->dev, for a start.
> I know that the other prints don't use this, but we could use it one
> time then slowly add more users until more are using dev_info() than
> pr_info() and then someone will decide to clean up the old users.
update as below
---
if (msi_enable == 1)
dev_info(&pdev->dev, "msi enabled\n");
>
> regards,
> dan carpenter
>
