[libvirt] [PATCH v2 9/9] pci: Add debug messages when unbinding from stub driver

[John Ferlan]

On 01/25/2016 11:21 AM, Andrea Bolognani wrote:
> Unbinding a PCI device from the stub driver can require several steps,
> and it can be useful for debugging to be able to trace which of these
> steps are performed and which are skipped for each device.
> ---
>  src/util/virpci.c | 22 ++++++++++++++++++----
>  1 file changed, 18 insertions(+), 4 deletions(-)
> 
> diff --git a/src/util/virpci.c b/src/util/virpci.c
> index f56dbe6..51a3f88 100644
> --- a/src/util/virpci.c
> +++ b/src/util/virpci.c
> @@ -1106,26 +1106,37 @@ virPCIDeviceUnbindFromStub(virPCIDevicePtr dev)
>  
>      if (!driver) {
>          /* The device is not bound to any driver and we are almost done. */
> +        VIR_DEBUG("PCI device %s is not bound to any driver", dev->name);
>          goto reprobe;
>      }
>  
> -    if (!dev->unbind_from_stub)
> +    if (!dev->unbind_from_stub) {
> +        VIR_DEBUG("Unbind from stub skipped for PCI device %s", dev->name);
>          goto remove_slot;
> +    }
>  
>      /* If the device isn't bound to a known stub, skip the unbind. */
>      if (virPCIStubDriverTypeFromString(driver) < 0 ||
> -        virPCIStubDriverTypeFromString(driver) == VIR_PCI_STUB_DRIVER_NONE)
> +        virPCIStubDriverTypeFromString(driver) == VIR_PCI_STUB_DRIVER_NONE) {
> +        VIR_DEBUG("Unbind from stub skipped for PCI device %s because of "
> +                  "unknown stub driver", dev->name);
>          goto remove_slot;
> +    }
>  
> -    VIR_DEBUG("Found stub driver %s", driver);
> +    VIR_DEBUG("Found stub driver %s for PCI device %s", driver, dev->name);
> +    VIR_DEBUG("Unbinding PCI device %s", dev->name);

Redundant - How about "Found stub driver %s to unbind PCI device %s" or
"Unbinding PCI device %s for stub driver %s" (don't forget to change
order of args ;-))

IOW: No need to have two messages.

Hope they help some day!

ACK -

John
>  
>      if (virPCIDeviceUnbind(dev) < 0)
>          goto cleanup;
>      dev->unbind_from_stub = false;
>  
>   remove_slot:
> -    if (!dev->remove_slot)
> +    if (!dev->remove_slot) {
> +        VIR_DEBUG("Slot removal skipped for PCI device %s", dev->name);
>          goto reprobe;
> +    }
> +
> +    VIR_DEBUG("Removing slot for PCI device %s", dev->name);
>  
>      /* Xen's pciback.ko wants you to use remove_slot on the specific device */
>      if (!(path = virPCIDriverFile(driver, "remove_slot")))
> @@ -1141,10 +1152,13 @@ virPCIDeviceUnbindFromStub(virPCIDevicePtr dev)
>  
>   reprobe:
>      if (!dev->reprobe) {
> +        VIR_DEBUG("Reprobe skipped for PCI device %s", dev->name);
>          result = 0;
>          goto cleanup;
>      }
>  
> +    VIR_DEBUG("Reprobing for PCI device %s", dev->name);
> +
>      /* Trigger a re-probe of the device is not in the stub's dynamic
>       * ID table. If the stub is available, but 'remove_id' isn't
>       * available, then re-probing would just cause the device to be
>