[PATCH V10 06/12] powerpc/powernv: EEH device for VF

[Wei Yang]

On Fri, Oct 30, 2015 at 06:36:01PM +1100, Alexey Kardashevskiy wrote:
>On 10/30/2015 05:52 PM, Wei Yang wrote:
>>On Fri, Oct 30, 2015 at 02:33:49PM +1100, Alexey Kardashevskiy wrote:
>>>On 10/26/2015 02:15 PM, Wei Yang wrote:
>>>>VFs and their corresponding pci_dn instances are created and released
>>>>dynamically as their PF's SRIOV capability is enabled and disabled.
>>>>The patch creates and releases EEH devices for VFs when creating and
>>>>releasing their pci_dn instances, which means EEH devices and pci_dn
>>>>instances have same life cycle. Also, VF's EEH device is identified
>>>>by (struct eeh_dev::physfn).
>>>
>>>
>>>The add_dev_pci_data() helper (the one you hack) does not create pci_dn
>>>instances. The add_one_dev_pci_data() helper does.
>>>
>>
>>Yes, you are right. The patch here create edev after the pci_dn is created.
>>
>>So which part in the log you think is not accurate?
>
>
>The commit log is ok, I just thought loud that eeh_dev_init() could go to
>add_one_dev_pci_data() to make things more clear.
>

I thought this is are good suggestion.

My thought is, when we don't have VF, pci_dn and edev are two different thing.
We create pci_dn first and then initialize the edev. So mix the initialization
of them together is not that clear.

Not sure you agree or not.

>
>
>>>
>>>>
>>>>[gwshan: changelog and removed CONFIG_PCI_IOV]
>>>>Signed-off-by: Wei Yang <weiyang at linux.vnet.ibm.com>
>>>>Acked-by: Gavin Shan <gwshan at linux.vnet.ibm.com>
>>>>---
>>>>  arch/powerpc/include/asm/eeh.h |  1 +
>>>>  arch/powerpc/kernel/pci_dn.c   | 12 ++++++++++++
>>>>  2 files changed, 13 insertions(+)
>>>>
>>>>diff --git a/arch/powerpc/include/asm/eeh.h b/arch/powerpc/include/asm/eeh.h
>>>>index c5eb86f..6c383ad 100644
>>>>--- a/arch/powerpc/include/asm/eeh.h
>>>>+++ b/arch/powerpc/include/asm/eeh.h
>>>>@@ -140,6 +140,7 @@ struct eeh_dev {
>>>>  	struct pci_controller *phb;	/* Associated PHB		*/
>>>>  	struct pci_dn *pdn;		/* Associated PCI device node	*/
>>>>  	struct pci_dev *pdev;		/* Associated PCI device	*/
>>>>+	struct pci_dev *physfn;		/* Associated PF PORT		*/
>>>>  	struct pci_bus *bus;		/* PCI bus for partial hotplug	*/
>>>>  };
>>>>
>>>>diff --git a/arch/powerpc/kernel/pci_dn.c b/arch/powerpc/kernel/pci_dn.c
>>>>index f771130..f0ddde7 100644
>>>>--- a/arch/powerpc/kernel/pci_dn.c
>>>>+++ b/arch/powerpc/kernel/pci_dn.c
>>>>@@ -180,7 +180,9 @@ static struct pci_dn *add_one_dev_pci_data(struct pci_dn *parent,
>>>>  struct pci_dn *add_dev_pci_data(struct pci_dev *pdev)
>>>>  {
>>>>  #ifdef CONFIG_PCI_IOV
>>>>+	struct pci_controller *hose = pci_bus_to_host(pdev->bus);
>>>>  	struct pci_dn *parent, *pdn;
>>>>+	struct eeh_dev *edev;
>>>>  	int i;
>>>>
>>>>  	/* Only support IOV for now */
>>>>@@ -206,6 +208,9 @@ struct pci_dn *add_dev_pci_data(struct pci_dev *pdev)
>>>>  				 __func__, i);
>>>>  			return NULL;
>>>>  		}
>>>>+		eeh_dev_init(pdn, hose);
>>>>+		edev = pdn_to_eeh_dev(pdn);
>>>
>>>
>>>In theory, pdn_to_eeh_dev() can return NULL. In this patch, it is not clear
>>>if pdn->edev gets initialized before or after add_dev_pci_data().
>>>
>>
>>Yep, the return value should be checked.
>
>May be BUG_ON will be enough, up to you.
>

Yep, thanks.

>
>>
>>pdn->edev is initialized in eeh_dev_init() which is called in
>>add_dev_pci_data(). The order is not clear?
>>
>>>
>>>
>>>>+		edev->physfn = pdev;
>>>>  	}
>>>>  #endif /* CONFIG_PCI_IOV */
>>>>
>>>>@@ -254,10 +259,17 @@ void remove_dev_pci_data(struct pci_dev *pdev)
>>>>  	for (i = 0; i < pci_sriov_get_totalvfs(pdev); i++) {
>>>>  		list_for_each_entry_safe(pdn, tmp,
>>>>  			&parent->child_list, list) {
>>>>+			struct eeh_dev *edev;
>>>>  			if (pdn->busno != pci_iov_virtfn_bus(pdev, i) ||
>>>>  			    pdn->devfn != pci_iov_virtfn_devfn(pdev, i))
>>>>  				continue;
>>>>
>>>>+			edev = pdn_to_eeh_dev(pdn);
>>>>+			if (edev) {
>>>>+				pdn->edev = NULL;
>>>>+				kfree(edev);
>>>>+			}
>>>>+
>>>>  			if (!list_empty(&pdn->list))
>>>>  				list_del(&pdn->list);
>>>>
>>>>
>>>
>
>
>-- 
>Alexey

-- 
Richard Yang
Help you, Help me