Subject: Re: [PATCH V3 2/9] powerpc/pci_dn: cache vf_index in pci_dn

From: Wei Yang <[email-masked]>
Date: Mon, 11 May 2015 13:54:12 +0800

On Mon, May 11, 2015 at 12:21:04PM +1000, Gavin Shan wrote:
>On Mon, May 04, 2015 at 03:07:31PM +0800, Wei Yang wrote:
>>This patch caches the index of a VF in its PF in pci_dn.
>>
>
>At least you can mention the purpose of vf_index to make the commit log
>complete. The following message looks better?
>
>The patch caches the VF index in pci_dn, which can be used to calculate
>VF's bus, device and function number. Those information helps to locate
>the VF's PCI device instance when doing hotplug during EEH recovery if
>necessary.
>

Thanks, looks better. I added it in the log.

>>Signed-off-by: Wei Yang <[email-masked]>
>>---
>> arch/powerpc/include/asm/pci-bridge.h |    1 +
>> arch/powerpc/kernel/pci_dn.c          |    5 +++--
>> 2 files changed, 4 insertions(+), 2 deletions(-)
>>
>>diff --git a/arch/powerpc/include/asm/pci-bridge.h b/arch/powerpc/include/asm/pci-bridge.h
>>index 1811c44..9582aa2 100644
>>--- a/arch/powerpc/include/asm/pci-bridge.h
>>+++ b/arch/powerpc/include/asm/pci-bridge.h
>>@@ -199,6 +199,7 @@ struct pci_dn {
>> #ifdef CONFIG_PCI_IOV
>> 	u16     vfs_expanded;		/* number of VFs IOV BAR expanded */
>> 	u16     num_vfs;		/* number of VFs enabled*/
>>+	int     vf_index;		/* Index to PF for VF dev */
>                                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
>					/* VF index in the PF */

Ok, changed in the code.

>
>And I believe it can be "unsigned int", or u16. We should have
>non-negative vf_index, no?

Take a look in the virtfn_add(), the index in drivers/pci/iov.c is int. So I
copy that.

>
>> 	int     offset;			/* PE# for the first VF PE */
>> #define M64_PER_IOV 4
>> 	int     m64_per_iov;
>>diff --git a/arch/powerpc/kernel/pci_dn.c b/arch/powerpc/kernel/pci_dn.c
>>index b3b4df9..bf0fb873 100644
>>--- a/arch/powerpc/kernel/pci_dn.c
>>+++ b/arch/powerpc/kernel/pci_dn.c
>>@@ -138,7 +138,7 @@ struct pci_dn *pci_get_pdn(struct pci_dev *pdev)
>>
>> #ifdef CONFIG_PCI_IOV
>> static struct pci_dn *add_one_dev_pci_data(struct pci_dn *parent,
>>-					   struct pci_dev *pdev,
>>+					   struct pci_dev *pdev, int vf_index,
>
>					   struct pci_dev *pdev,
>					   int vf_index;

Some reason for this comment?

That does not exceed 80 characters.

>
>> 					   int busno, int devfn)
>> {
>> 	struct pci_dn *pdn;
>>@@ -157,6 +157,7 @@ static struct pci_dn *add_one_dev_pci_data(struct pci_dn *parent,
>> 	pdn->parent = parent;
>> 	pdn->busno = busno;
>> 	pdn->devfn = devfn;
>>+	pdn->vf_index = vf_index;
>> #ifdef CONFIG_PPC_POWERNV
>> 	pdn->pe_number = IODA_INVALID_PE;
>> #endif
>>@@ -196,7 +197,7 @@ struct pci_dn *add_dev_pci_data(struct pci_dev *pdev)
>> 		return NULL;
>>
>> 	for (i = 0; i < pci_sriov_get_totalvfs(pdev); i++) {
>>-		pdn = add_one_dev_pci_data(parent, NULL,
>>+		pdn = add_one_dev_pci_data(parent, NULL, i,
>> 					   pci_iov_virtfn_bus(pdev, i),
>> 					   pci_iov_virtfn_devfn(pdev, i));
>> 		if (!pdn) {
>
>Thanks,
>Gavin

-- 
Richard Yang
Help you, Help me