Re: [RFC 2/3] mac80211: Support scanning only current active channel.

[Ben Greear <greearb@candelatech.com>]

On 01/20/2011 10:17 AM, Johannes Berg wrote:
> On Thu, 2011-01-20 at 10:06 -0800, Ben Greear wrote:
>
>>> This doesn't seem to make much sense either -- even if we do a scan over
>>> multiple channels we should be able to optimise the part on the current
>>> channel (maybe put it at the beginning or end too).
>>
>> Maybe..but user-space can specify the channels it wants to scan,
>> and I assume that means what order to scan them in.  I have no
>> idea if changing that order would confuse some application.
>
> No, it can't actually determine the order -- we sort them in cfg80211
> anyway to de-duplicate them.

Ok, so assuming we re-work scanning across the board, maybe the first
thing is to sort them such that the current channel is always first
(if it's in the list at all)?

>> It seems to me that it would take quite a bit of re-work of the
>> mac80211 scanning logic to deal with scanning on the current
>> channel w/out affecting other tx/rx packets (as my patch attempts
>> to do), without setting some explicit flag before you enter
>> the scan state machine.
>
> Yeah, so maybe it needs some re-work, but I think what you're doing is a
> pretty strange hack.

If you have time to write some patches, I'll be happy to test them on
our ath9k and ath5k systems.

If you don't, then I can make an attempt.  Suggestions for an acceptable
way to go about doing this would be welcome.

Thanks,
Ben


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