[PATCH] Decrease cross-threshold roam difficulty

[Matthew Wang]

Please ignore this, I resent this as a series.

On Tue, Dec 26, 2023 at 6:52 PM Matthew Wang <matthewmwang at chromium.org> wrote:
>
> Decrease the roam difficulty when roaming across the short background
> scan threshold (i.e. when the current BSS RSSI is below the threshold
> and the selected BSS RSSI is above the threshold). This tends to happen
> in normal roaming scenarios when moving from the domain of one AP to
> the domain of another.
>
> Signed-off-by: Matthew Wang <matthewmwang at chromium.org>
> ---
>  wpa_supplicant/bgscan_simple.c    | 5 ++++-
>  wpa_supplicant/events.c           | 3 +++
>  wpa_supplicant/wpa_supplicant_i.h | 1 +
>  3 files changed, 8 insertions(+), 1 deletion(-)
>
> diff --git a/wpa_supplicant/bgscan_simple.c b/wpa_supplicant/bgscan_simple.c
> index cac3049e3..a90cf86e5 100644
> --- a/wpa_supplicant/bgscan_simple.c
> +++ b/wpa_supplicant/bgscan_simple.c
> @@ -189,6 +189,7 @@ static void * bgscan_simple_init(struct wpa_supplicant *wpa_s,
>         data->scan_interval = data->short_interval;
>         data->max_short_scans = data->long_interval / data->short_interval + 1;
>         if (data->signal_threshold) {
> +               wpa_s->signal_threshold = data->signal_threshold;
>                 /* Poll for signal info to set initial scan interval */
>                 struct wpa_signal_info siginfo;
>                 if (wpa_drv_signal_poll(wpa_s, &siginfo) == 0 &&
> @@ -216,8 +217,10 @@ static void bgscan_simple_deinit(void *priv)
>  {
>         struct bgscan_simple_data *data = priv;
>         eloop_cancel_timeout(bgscan_simple_timeout, data, NULL);
> -       if (data->signal_threshold)
> +       if (data->signal_threshold) {
> +               data->wpa_s->signal_threshold = 0;
>                 wpa_drv_signal_monitor(data->wpa_s, 0, 0);
> +       }
>         os_free(data);
>  }
>
> diff --git a/wpa_supplicant/events.c b/wpa_supplicant/events.c
> index 7bea64986..47169c181 100644
> --- a/wpa_supplicant/events.c
> +++ b/wpa_supplicant/events.c
> @@ -2284,6 +2284,9 @@ int wpa_supplicant_need_to_roam_within_ess(struct wpa_supplicant *wpa_s,
>                 min_diff -= 2;
>         if (to_6ghz)
>                 min_diff -= 2;
> +       if (wpa_s->signal_threshold && cur_level <= wpa_s->signal_threshold &&
> +           sel_level > wpa_s->signal_threshold)
> +               min_diff -= 2;
>         diff = sel_level - cur_level;
>         if (diff < min_diff) {
>                 wpa_dbg(wpa_s, MSG_DEBUG,
> diff --git a/wpa_supplicant/wpa_supplicant_i.h b/wpa_supplicant/wpa_supplicant_i.h
> index b3f1cd1b4..86c25bd8d 100644
> --- a/wpa_supplicant/wpa_supplicant_i.h
> +++ b/wpa_supplicant/wpa_supplicant_i.h
> @@ -1191,6 +1191,7 @@ struct wpa_supplicant {
>         struct wpa_ssid *bgscan_ssid;
>         const struct bgscan_ops *bgscan;
>         void *bgscan_priv;
> +       int signal_threshold;
>
>         const struct autoscan_ops *autoscan;
>         struct wpa_driver_scan_params *autoscan_params;
> --
> 2.43.0.472.g3155946c3a-goog
>