Re: [RFC] mac80211: Add station uptime in debugfs

[Felix Fietkau <nbd@openwrt.org>]

On 2011-04-05 5:04 PM, Mohammed Shafi wrote:
> On Tuesday 05 April 2011 07:38 PM, Felix Fietkau wrote:
>>  On 2011-04-05 3:39 PM, Mohammed Shafi Shajakhan wrote:
>>
>>>  From: Mohammed Shafi Shajakhan<mshajakhan@atheros.com>
>>>
>>>  Add station uptime parameter in debugfs. This will be helpful to get a
>>>  measure of stability of connection and also during stress testing.
>>>
>>>  Signed-off-by: Mohammed Shafi Shajakhan<mshajakhan@atheros.com>
>>>
>>
>>>  diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
>>>  index 999f8fb..08b9f51 100644
>>>  --- a/net/mac80211/sta_info.c
>>>  +++ b/net/mac80211/sta_info.c
>>>  @@ -244,6 +244,7 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
>>>     	sta->local = local;
>>>     	sta->sdata = sdata;
>>>     	sta->last_rx = jiffies;
>>>  +	sta->sta_uptime = jiffies;
>>>
>>>     	ewma_init(&sta->avg_signal, 1024, 8);
>>>
>>>
>>  I think jiffies can easily overflow. Maybe it would be better to get a
>>  timeval from the monotonic clock.
>>
> Thanks, yes thats true and I assumed this will work fine for 49 days
> assuming 32 bit(please correct me if my calculations are wrong). will
> the overflow will take place in less than this time?.
Yes, but there are people that deploy point to point links that can last 
longer than that ;)

> I will dig more into it by looking at the time val.
Thanks.

- Felix