Subject: Re: [PATCH 2/2] powerpc/eeh: Reworked eeh_pe_bus_get()

From: Gavin Shan <[email-masked]>
Date: Tue, 9 Feb 2016 09:40:55 +1100

On Mon, Feb 08, 2016 at 04:35:19PM +1100, Gavin Shan wrote:
>The original implementation is ugly: unnecessary if statements and
>"out" tag. This reworks the function to avoid above weaknesses. No
>functional changes introduced.
>
>Signed-off-by: Gavin Shan <[email-masked]>

Michael, please ignore this one now because it conflicts with another
patch which needs to be ported to stable. I'll repost all of them
later.

Thanks,
Gavin

>---
> arch/powerpc/kernel/eeh_pe.c | 28 ++++++++++++----------------
> 1 file changed, 12 insertions(+), 16 deletions(-)
>
>diff --git a/arch/powerpc/kernel/eeh_pe.c b/arch/powerpc/kernel/eeh_pe.c
>index 8654cb1..1d64e60 100644
>--- a/arch/powerpc/kernel/eeh_pe.c
>+++ b/arch/powerpc/kernel/eeh_pe.c
>@@ -923,25 +923,21 @@ out:
>  */
> struct pci_bus *eeh_pe_bus_get(struct eeh_pe *pe)
> {
>-	struct pci_bus *bus = NULL;
> 	struct eeh_dev *edev;
> 	struct pci_dev *pdev;
>
>-	if (pe->type & EEH_PE_PHB) {
>-		bus = pe->phb->bus;
>-	} else if (pe->type & EEH_PE_BUS ||
>-		   pe->type & EEH_PE_DEVICE) {
>-		if (pe->bus) {
>-			bus = pe->bus;
>-			goto out;
>-		}
>+	if (pe->type & EEH_PE_PHB)
>+		return pe->phb->bus;
>
>-		edev = list_first_entry(&pe->edevs, struct eeh_dev, list);
>-		pdev = eeh_dev_to_pci_dev(edev);
>-		if (pdev)
>-			bus = pdev->bus;
>-	}
>+	/* The primary bus might be cached during probe time */
>+	if (pe->bus)
>+		return pe->bus;
>
>-out:
>-	return bus;
>+	/* Retrieve the parent PCI bus of first (top) PCI device */
>+	edev = list_first_entry_or_null(&pe->edevs, struct eeh_dev, list);
>+	pdev = eeh_dev_to_pci_dev(edev);
>+	if (pdev)
>+		return pdev->bus;
>+
>+	return NULL;
> }
>-- 
>2.1.0
>