Re: [Qemu-devel] [RFC 1/3] spapr: Fold spapr_phb_add_pci_device() into its only caller

[Michael Roth]

Quoting David Gibson (2017-06-06 08:05:32)
> This function is fairly short, and so is its only caller.  There's no
> particular logical distinction between them, so fold them together.
> 
> Signed-off-by: David Gibson <address@hidden>
> ---
>  hw/ppc/spapr_pci.c | 53 ++++++++++++++++++++++-------------------------------
>  1 file changed, 22 insertions(+), 31 deletions(-)
> 
> diff --git a/hw/ppc/spapr_pci.c b/hw/ppc/spapr_pci.c
> index 46e736d..a216f61 100644
> --- a/hw/ppc/spapr_pci.c
> +++ b/hw/ppc/spapr_pci.c
> @@ -1344,30 +1344,6 @@ static int spapr_create_pci_child_dt(sPAPRPHBState 
> *phb, PCIDevice *dev,
>      return offset;
>  }
> 
> -static void spapr_phb_add_pci_device(sPAPRDRConnector *drc,
> -                                     sPAPRPHBState *phb,
> -                                     PCIDevice *pdev,
> -                                     Error **errp)
> -{
> -    DeviceState *dev = DEVICE(pdev);
> -    void *fdt = NULL;
> -    int fdt_start_offset = 0, fdt_size;
> -
> -    fdt = create_device_tree(&fdt_size);
> -    fdt_start_offset = spapr_create_pci_child_dt(phb, pdev, fdt, 0);
> -    if (!fdt_start_offset) {
> -        error_setg(errp, "Failed to create pci child device tree node");
> -        goto out;
> -    }
> -
> -    spapr_drc_attach(drc, DEVICE(pdev),
> -                     fdt, fdt_start_offset, !dev->hotplugged, errp);
> -out:
> -    if (*errp) {
> -        g_free(fdt);
> -    }
> -}
> -
>  /* Callback to be called during DRC release. */
>  void spapr_phb_remove_pci_device_cb(DeviceState *dev)
>  {
> @@ -1429,6 +1405,8 @@ static void spapr_phb_hot_plug_child(HotplugHandler 
> *plug_handler,
>      Error *local_err = NULL;
>      PCIBus *bus = PCI_BUS(qdev_get_parent_bus(DEVICE(pdev)));
>      uint32_t slotnr = PCI_SLOT(pdev->devfn);
> +    void *fdt = NULL;
> +    int fdt_start_offset, fdt_size;
> 
>      /* if DR is disabled we don't need to do anything in the case of
>       * hotplug or coldplug callbacks
> @@ -1438,10 +1416,10 @@ static void spapr_phb_hot_plug_child(HotplugHandler 
> *plug_handler,
>           * we need to let them know it's not enabled
>           */
>          if (plugged_dev->hotplugged) {
> -            error_setg(errp, QERR_BUS_NO_HOTPLUG,
> +            error_setg(&local_err, QERR_BUS_NO_HOTPLUG,
>                         object_get_typename(OBJECT(phb)));
>          }
> -        return;
> +        goto out;
>      }
> 
>      g_assert(drc);
> @@ -1452,16 +1430,23 @@ static void spapr_phb_hot_plug_child(HotplugHandler 
> *plug_handler,
>       */
>      if (plugged_dev->hotplugged && bus->devices[PCI_DEVFN(slotnr, 0)] &&
>          PCI_FUNC(pdev->devfn) != 0) {
> -        error_setg(errp, "PCI: slot %d function 0 already ocuppied by %s,"
> +        error_setg(&local_err, "PCI: slot %d function 0 already ocuppied by 
> %s,"
>                     " additional functions can no longer be exposed to 
> guest.",
>                     slotnr, bus->devices[PCI_DEVFN(slotnr, 0)]->name);
> -        return;
> +        goto out;
>      }
> 
> -    spapr_phb_add_pci_device(drc, phb, pdev, &local_err);

Since we never used local_err outside propagating it and immediately
bailing, and since we bail on errp in all prior callers, maybe we
should just drop local_err completely in favor errp.

> +    fdt = create_device_tree(&fdt_size);
> +    fdt_start_offset = spapr_create_pci_child_dt(phb, pdev, fdt, 0);
> +    if (!fdt_start_offset) {
> +        error_setg(&local_err, "Failed to create pci child device tree 
> node");
> +        goto out;
> +    }
> +
> +    spapr_drc_attach(drc, DEVICE(pdev), fdt, fdt_start_offset,
> +                     !plugged_dev->hotplugged, &local_err);
>      if (local_err) {
> -        error_propagate(errp, local_err);
> -        return;
> +        goto out;
>      }
> 
>      /* If this is function 0, signal hotplug for all the device functions.
> @@ -1485,6 +1470,12 @@ static void spapr_phb_hot_plug_child(HotplugHandler 
> *plug_handler,
>              }
>          }
>      }
> +
> +out:
> +    if (local_err) {
> +        error_propagate(errp, local_err);
> +        g_free(fdt);
> +    }
>  }
> 
>  static void spapr_phb_hot_unplug_child(HotplugHandler *plug_handler,
> -- 
> 2.9.4
>