Subject: Re: [PATCH V3 5/9] powerpc/eeh: create EEH_PE_VF for VF PE

From: Wei Yang <[email-masked]>
Date: Mon, 11 May 2015 14:25:49 +0800

On Mon, May 11, 2015 at 12:37:07PM +1000, Gavin Shan wrote:
>On Mon, May 04, 2015 at 03:07:34PM +0800, Wei Yang wrote:
>
>Please reorder PATCH[6] with this one because the EEH device is expected
>to be created before EEH PE.

That's a good idea.

>
>>On powernv platform, VF PE is a special PE which is different from the Bus
>>PE.  On the EEH side, it needs a corresponding concept to handle the VF PE
>>properly. For example, we need to create VF PE when VF's pci_dev is
>>initialized in kernel. And add a flag to mark it is a VF PF.
>                                                       ^^^^^
>>
>
>>>From above commit log, my understanding is that you're adding a flag to
>identify VF PE, which is handled differently from bus PE. You missed the
>details on the difference between them and the speical treament to VF PE.
>Could you help add those information in the commit log to make it looks
>complete?
>

This patch just introduce the VF PE. For those differences, we have another
patch "handle VF PE properly" to cover. In the log of that patch, I listed
those differences. Do you think this is fine?

>>This patch introduces the EEH_PE_VF type for VF PE and creates it for a VF.
>>At the mean time, it creates the sysfs and address cache for VF PE.
>                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
>                   it creates the sysfs and address cache for VF PE at PCI
>device final fixup time.
>
>>
>>Signed-off-by: Wei Yang <[email-masked]>
>>---
>> arch/powerpc/include/asm/eeh.h               |    1 +
>> arch/powerpc/kernel/eeh_pe.c                 |   12 ++++++++++--
>> arch/powerpc/platforms/powernv/eeh-powernv.c |   12 ++++++++++++
>> 3 files changed, 23 insertions(+), 2 deletions(-)
>>
>>diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h
>>index a52db28..56e8cd9 100644
>>--- a/arch/powerpc/include/asm/eeh.h
>>+++ b/arch/powerpc/include/asm/eeh.h
>>@@ -70,6 +70,7 @@ struct pci_dn;
>> #define EEH_PE_PHB	(1 << 1)	/* PHB PE    */
>> #define EEH_PE_DEVICE 	(1 << 2)	/* Device PE */
>> #define EEH_PE_BUS	(1 << 3)	/* Bus PE    */
>>+#define EEH_PE_VF	(1 << 4)	/* VF PE     */
>>
>> #define EEH_PE_ISOLATED		(1 << 0)	/* Isolated PE		*/
>> #define EEH_PE_RECOVERING	(1 << 1)	/* Recovering PE	*/
>>diff --git a/arch/powerpc/kernel/eeh_pe.c b/arch/powerpc/kernel/eeh_pe.c
>>index 35f0b62..edfe63a 100644
>>--- a/arch/powerpc/kernel/eeh_pe.c
>>+++ b/arch/powerpc/kernel/eeh_pe.c
>>@@ -299,7 +299,12 @@ static struct eeh_pe *eeh_pe_get_parent(struct eeh_dev *edev)
>> 	 * EEH device already having associated PE, but
>> 	 * the direct parent EEH device doesn't have yet.
>> 	 */
>>-	pdn = pdn ? pdn->parent : NULL;
>>+#ifdef CONFIG_PCI_IOV
>>+	if (edev->mode & EEH_DEV_VF)
>>+		pdn = pci_get_pdn(edev->physfn);
>>+	else
>>+#endif
>>+		pdn = pdn ? pdn->parent : NULL;
>
>[A]
>
>> 	while (pdn) {
>> 		/* We're poking out of PCI territory */
>> 		parent = pdn_to_eeh_dev(pdn);
>>@@ -382,7 +387,10 @@ int eeh_add_to_parent_pe(struct eeh_dev *edev)
>> 	}
>>
>> 	/* Create a new EEH PE */
>>-	pe = eeh_pe_alloc(edev->phb, EEH_PE_DEVICE);
>>+	if (edev->mode & EEH_DEV_VF)
>>+		pe = eeh_pe_alloc(edev->phb, EEH_PE_VF);
>>+	else
>>+		pe = eeh_pe_alloc(edev->phb, EEH_PE_DEVICE);
>
>You don't have CONFIG_PCI_IOV here to protect the code, but you had
>that at [A]. In order to keep the code look consistent, you either
>add it or remove it for all places. I prefer to remove it, which
>we don't need CONFIG_PCI_IOV.
>

Ok, that's fine to remove it.

BTW, if remove the CONFIG_PCI_IOV, we need to remove it around the physfn in
eeh_dev definition. That's fine?

>> 	if (!pe) {
>> 		pr_err("%s: out of memory!\n", __func__);
>> 		return -ENOMEM;
>>diff --git a/arch/powerpc/platforms/powernv/eeh-powernv.c b/arch/powerpc/platforms/powernv/eeh-powernv.c
>>index 622f08c..5447481 100644
>>--- a/arch/powerpc/platforms/powernv/eeh-powernv.c
>>+++ b/arch/powerpc/platforms/powernv/eeh-powernv.c
>>@@ -1540,3 +1540,15 @@ static int __init eeh_powernv_init(void)
>> 	return ret;
>> }
>> machine_early_initcall(powernv, eeh_powernv_init);
>>+
>>+#ifdef CONFIG_PCI_IOV
>>+static void pnv_pci_fixup_vf_eeh(struct pci_dev *pdev)
>>+{
>
>Please rename it to pnv_eeh_vf_final_fixup(). Names of all functions
>in this file expect prefix "pnv_eeh_". With "_final_", it's clearly
>to tell it's called on PCI device final fixup time.
>

ok

>>+	/* sysfs files should only be added after devices are added */
>
>It's nice to explain why here: sysfs for the PCI device isn't populated
>and the MMIO resource isn't finalized for the PCI device yet.
>

Don't get your point.

sysfs of the PCI device is populated at this point.

>>+	if (pdev->is_virtfn) {
>>+		eeh_add_device_late(pdev);
>>+		eeh_sysfs_add_device(pdev);
>>+	}
>>+}
>
>The nested ifdef can be avoided as:
>
>	if (!pdev->is_virtfn)
>		return;
>
>	eeh_add_device_late(pdev);
>	eeh_sysfs_add_device(pdev);
>

Ok.

>>+DECLARE_PCI_FIXUP_FINAL(PCI_ANY_ID, PCI_ANY_ID, pnv_pci_fixup_vf_eeh);
>>+#endif /* CONFIG_PCI_IOV */
>
>Thanks,
>Gavin

-- 
Richard Yang
Help you, Help me