On Tue, Jan 25, 2022 at 05:17:42PM +0800, Zhu Lingshan wrote:
> This commit implements a MSIX vector allocation helper
> for vqs and config interrupts.
> 
> Signed-off-by: Zhu Lingshan <[email protected]>
> ---
>  drivers/vdpa/ifcvf/ifcvf_main.c | 30 ++++++++++++++++++++++++++++--
>  1 file changed, 28 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
> index d1a6b5ab543c..7e2af2d2aaf5 100644
> --- a/drivers/vdpa/ifcvf/ifcvf_main.c
> +++ b/drivers/vdpa/ifcvf/ifcvf_main.c
> @@ -58,14 +58,40 @@ static void ifcvf_free_irq(struct ifcvf_adapter *adapter, 
> int queues)
>       ifcvf_free_irq_vectors(pdev);
>  }
>  
> +static int ifcvf_alloc_vectors(struct ifcvf_adapter *adapter)


So the helper returns an int...

> +{
> +     struct pci_dev *pdev = adapter->pdev;
> +     struct ifcvf_hw *vf = &adapter->vf;
> +     u16 max_intr, ret;
> +
> +     /* all queues and config interrupt  */
> +     max_intr = vf->nr_vring + 1;
> +     ret = pci_alloc_irq_vectors(pdev, 1, max_intr, PCI_IRQ_MSIX | 
> PCI_IRQ_AFFINITY);
> +
> +     if (ret < 0) {
> +             IFCVF_ERR(pdev, "Failed to alloc IRQ vectors\n");
> +             return ret;


which is negative on error...

> +     }
> +
> +     if (ret < max_intr)
> +             IFCVF_INFO(pdev,
> +                        "Requested %u vectors, however only %u allocated, 
> lower performance\n",
> +                        max_intr, ret);
> +
> +     return ret;
> +}
> +
>  static int ifcvf_request_irq(struct ifcvf_adapter *adapter)
>  {
>       struct pci_dev *pdev = adapter->pdev;
>       struct ifcvf_hw *vf = &adapter->vf;
>       int vector, i, ret, irq;
> -     u16 max_intr;
> +     u16 nvectors, max_intr;
> +
> +     nvectors = ifcvf_alloc_vectors(adapter);

which you proceed to stash into an unsigned int ...

> +     if (!(nvectors > 0))

and then compare to zero ...

> +             return nvectors;
>

correct error handling is unlikely as a result.

  
> -     /* all queues and config interrupt  */
>       max_intr = vf->nr_vring + 1;
>  
>       ret = pci_alloc_irq_vectors(pdev, max_intr,


As long as you are introducing a helper, document it's return
type and behaviour and then use correctly.

> -- 
> 2.27.0

_______________________________________________
Virtualization mailing list
[email protected]
https://lists.linuxfoundation.org/mailman/listinfo/virtualization

Reply via email to