Re: [PATCH 3/6] PCI/AER: clean all untracked pci_ops_aer when rmmod aer_inject

[Yijing Wang <wangyijing@huawei.com>]

On 2012/9/19 13:57, Huang Ying wrote:
> On Wed, 2012-09-19 at 10:40 +0800, Yijing Wang wrote:
>> Since hot plug for pci devices while doing aer inject, some newly created child buses'
>> pci_ops will be assigned to pci_ops_aer. Aer_inject does not track these pci_ops_aer(not
>> list in pci_bus_ops_list),we should clean all of these when rmmod aer_inject module.
>>
>> Signed-off-by: Yijing Wang <wangyijing@huawei.com>
>> ---
>>  drivers/pci/pcie/aer/aer_inject.c |   35 +++++++++++++++++++++++++++++++++++
>>  1 files changed, 35 insertions(+), 0 deletions(-)
>>
>> diff --git a/drivers/pci/pcie/aer/aer_inject.c b/drivers/pci/pcie/aer/aer_inject.c
>> index 442147b..e2400b5 100644
>> --- a/drivers/pci/pcie/aer/aer_inject.c
>> +++ b/drivers/pci/pcie/aer/aer_inject.c
>> @@ -299,6 +299,32 @@ static void pci_bus_ops_init(struct pci_bus_ops *bus_ops,
>>  	bus_ops->ops = ops;
>>  }
>>  
>> +static void pci_clean_child_aer_ops(struct pci_bus *bus)
>> +{
>> +	struct pci_bus *child;
>> +
>> +	list_for_each_entry(child, &bus->children, node) {
>> +		if (child->ops == &pci_ops_aer)
>> +			pci_bus_set_ops(child, bus->ops);
>> +		pci_clean_child_aer_ops(child);
>> +	}
> 
> Why not use pci_walk_bus?
> 

I think here walk all child buses is enough, pci_walk_bus will walk all child devices under this bus.

>> +}
>> +
>> +/* find pci_ops_aer from root bus, and replace it by parent bus's pci_ops.
>> + * pci_ops of root bus won't be pci_ops_aer here*/
>> +static void clean_untracked_pci_ops_aer(void)
>> +{
>> +	struct pci_bus_ops *bus_ops;
>> +
>> +	list_for_each_entry(bus_ops, &pci_bus_ops_list, list) {
>> +		/* the bus with untracked pci_ops_aer always the
>> +		 * child bus of root bus tracked in pci_bus_ops_list
>> +		 */
>> +		if (pci_is_root_bus(bus_ops->bus))
>> +			pci_clean_child_aer_ops(bus_ops->bus);
>> +	}
>> +}
>> +
>>  static int pci_bus_set_aer_ops(struct pci_bus *bus)
>>  {
>>  	struct pci_ops *ops;
>> @@ -558,9 +584,18 @@ static void __exit aer_inject_exit(void)
>>  
>>  	misc_deregister(&aer_inject_device);
>>  
>> +	/* clean pci_bus_ops tracked in pci_bus_ops_list */
>>  	while ((bus_ops = pci_bus_ops_get(bus_ops)))
>>  		pci_bus_set_ops(bus_ops->bus, bus_ops->ops);
> 
> Why not do clean here inside loop?
> 

Because I also need these bus_ops to scan untracked pci_ops_aer.

> Best Regards,
> Huang Ying
> 
>>  
>> +	/* Inject aer errors and hotplug the same pcie device
>> +	 * maybe assign some newly created buses' pci_ops pci_ops_aer.
>> +	 * Since these pci_ops_aer are not tracked in pci_bus_ops_list,
>> +	 * we need to find and clean untracked pci_ops_aer before aer_inject
>> +	 * module exit
>> +	 */
>> +	clean_untracked_pci_ops_aer();
>> +
>>  	while ((bus_ops = pci_bus_ops_pop()))
>>  		kfree(bus_ops);
>>  
> 
> 
> 
> .
> 


-- 
Thanks!
Yijing