Hi Michael,

On 7/12/21 8:17 AM, Michael Johnson wrote:
> Hi everyone,
> 
> I noticed that iwd wasn't roaming as much as I would expect given a
> modified RoamTheshold5G
> value. Looking into it, it seems like when the threshold is registered
> for updates in
> netdev_build_cmd_cqm_rssi_update we always use RoamThreshold. When
> this bit of code is
> called the frequency seems to always be 0 and so the non-5G variant is
> used. This in turn becomes an issue once the frequency is set and the
> correct threshold is used for other checks (at least if
> RoamThreshold5G is configured higher than RoamThreshold).
> 
> Code:
> netdev_build_cmd_cqm_rssi_update(...)
>      int threshold = netdev->frequency > 4000 ? LOW_SIGNAL_THRESHOLD_5GHZ :
> 
>     LOW_SIGNAL_THRESHOLD;
>      l_debug("frequency: %u, threshold: %d", netdev->frequency,
> threshold); // added for debug
> 
> Config:
> [General]
> EnableNetworkConfiguration=true
> RoamThreshold=-60
> RoamThreshold5G=-65
> 
> Output:
> src/netdev.c:netdev_build_cmd_cqm_rssi_update() frequency: 0, threshold: -60
> 

Yep, seems we forgot to invoke netdev_cqm_rssi_update() in 
netdev_connect/netdev_reassociate/netdev_fast_transition*

> I'm not really sure what the right fix for this is. Can it just
> request notifications for both
> thresholds?

Probably not.  If the driver doesn't support NL80211_EXT_FEATURE_CQM_RSSI_LIST, 
then we can only set a single threshold and we want that to be the roaming 
threshold.

Regards,
-Denis