Subject: Re: [PATCH v4 net-next] bonding: handle slave's name change with primary_slave logic

From: Veaceslav Falico <[email-masked]>
Date: Thu, 16 Jan 2014 02:40:23 +0100

On Thu, Jan 16, 2014 at 09:38:50AM +0800, Ding Tianhong wrote:
>On 2014/1/16 9:04, Veaceslav Falico wrote:
>> Currently, if a slave's name change, we just pass it by. However, if the
>> slave is a current primary_slave, then we end up with using a slave, whose
>> name != params.primary, for primary_slave. And vice-versa, if we don't have
>> a primary_slave but have params.primary set - we will not detected a new
>> primary_slave.
>>
>> Fix this by catching the NETDEV_CHANGENAME event and setting primary_slave
>> accordingly. Also, if the primary_slave was changed, issue a reselection of
>> the active slave, cause the priorities have changed.
>>
>> Reported-by: Ding Tianhong <[email-masked]>
>> CC: Ding Tianhong <[email-masked]>
>> CC: Jay Vosburgh <[email-masked]>
>> CC: Andy Gospodarek <[email-masked]>
>> Signed-off-by: Veaceslav Falico <[email-masked]>
>> ---
>>
>> Notes:
>>     v3->v4:
>>     Fix style issue.
>>
>>     v2->v3:
>>     Reword the info message, per Jay's comment.
>>
>>     v1->v2:
>>     Proper patch
>>
>>  drivers/net/bonding/bond_main.c | 24 +++++++++++++++++++++---
>>  1 file changed, 21 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
>> index f2fe6cb..f00dd45 100644
>> --- a/drivers/net/bonding/bond_main.c
>> +++ b/drivers/net/bonding/bond_main.c
>> @@ -2860,9 +2860,27 @@ static int bond_slave_netdev_event(unsigned long event,
>>  		 */
>>  		break;
>>  	case NETDEV_CHANGENAME:
>> -		/*
>> -		 * TODO: handle changing the primary's name
>> -		 */
>> +		/* we don't care if we don't have primary set */
>> +		if (!USES_PRIMARY(bond->params.mode) ||
>> +		    !bond->params.primary[0])
>> +			break;
>> +
>> +		if (slave == bond->primary_slave) {
>> +			/* slave's name changed - he's no longer primary */
>> +			bond->primary_slave = NULL;
>> +		} else if (!strcmp(slave_dev->name, bond->params.primary)) {
>> +			/* we have a new primary slave */
>> +			bond->primary_slave = slave;
>> +		} else { /* we didn't change primary - exit */
>> +			break;
>> +		}
>> +
>why not remove all the { } for the if else, there are only one line for each if.

It's written so in CodingStyles, as spotted by Sergei -
http://www.spinics.net/lists/netdev/msg266612.html .

>
>but seems good for logic.
>
>Acked-by: Ding Tianhong <[email-masked]>
>
>> +		pr_info("%s: Primary slave changed to %s, reselecting active slave.\n",
>> +			bond->dev->name, bond->primary_slave ? slave_dev->name :
>> +							       "none");
>> +		write_lock_bh(&bond->curr_slave_lock);
>> +		bond_select_active_slave(bond);
>> +		write_unlock_bh(&bond->curr_slave_lock);
>>  		break;
>>  	case NETDEV_FEAT_CHANGE:
>>  		bond_compute_features(bond);
>>
>
>