Re: [PATCH v3] mac80211: Allow scanning single channel if other VIF is associated.

[Ben Greear <greearb@candelatech.com>]

On 09/29/2010 09:48 AM, Johannes Berg wrote:
> On Wed, 2010-09-29 at 08:30 -0700, Ben Greear wrote:
>
>> Does this portion seem useful as a stand-alone patch?  It does not
>> depend on the other scan-one logic.
>
> Somewhat, but it seems a bit buggy?
>
>> diff --git a/net/mac80211/work.c b/net/mac80211/work.c
>> index ae344d1..1bfc1e0 100644
>> --- a/net/mac80211/work.c
>> +++ b/net/mac80211/work.c
>> @@ -910,12 +910,17 @@ static void ieee80211_work_work(struct work_struct *work)
>>    			 *	 happen to be on the same channel as
>>    			 *	 the requested channel
>>    			 */
>> -			ieee80211_offchannel_stop_beaconing(local);
>> -			ieee80211_offchannel_stop_station(local);
>> -
>> -			local->tmp_channel = wk->chan;
>> -			local->tmp_channel_type = wk->chan_type;
>> -			ieee80211_hw_config(local, 0);
>> +			if (!(wk->chan == local->scan_channel ||
>> +			      (wk->chan == local->oper_channel&&
>
> I don't think work items will ever run while scanning? And also, this
> might need to check the channel type as well, which isn't quite
> necessary right now (since no works requires HT channels) but would seem
> cleaner.

Just in case work ever does happen when scanning, I think we should
leave this check in.

I'll add a check for channel_type being the same as well.

>> +			       !local->scan_channel))) {
>> +				/* Only change channels if we need to */
>> +				ieee80211_offchannel_stop_beaconing(local);
>> +				ieee80211_offchannel_stop_station(local);
>> +
>> +				local->tmp_channel = wk->chan;
>> +				local->tmp_channel_type = wk->chan_type;
>> +				ieee80211_hw_config(local, 0);
>> +			}
>>    			started = true;
>>    			wk->timeout = jiffies;
>
> Also, I believe it needs matching code to not do all the return stuff
> since we never left the channel, and I think it still needs to set
> tmp_channel so that nothing will switch away underneath or so... not
> quite sure.

Ok, that sounds good.  I'll work on a revised patch when I get a chance.

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com