From: Johannes Berg <johannes.berg@xxxxxxxxx>
It doesn't seem problematic to change the weight for the average
beacon signal from 3 to 4, so use DECLARE_EWMA. This also makes
the code easier to maintain since bugs like the one fixed in the
previous patch can't happen as easily.
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
---
net/mac80211/ieee80211_i.h | 10 +++-------
net/mac80211/mlme.c | 20 ++++++--------------
net/mac80211/util.c | 2 +-
3 files changed, 10 insertions(+), 22 deletions(-)
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index e5b2dcbb6606..904b3bbafd93 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -419,6 +419,8 @@ struct ieee80211_sta_tx_tspec {
bool downgraded;
};
+DECLARE_EWMA(beacon_signal, 16, 4)
+
struct ieee80211_if_managed {
struct timer_list timer;
struct timer_list conn_mon_timer;
@@ -490,13 +492,7 @@ struct ieee80211_if_managed {
s16 p2p_noa_index;
- /*
- * Weighted average of the signal strength from Beacon frames in the
- * current BSS. This is in units of 1/16 of the signal unit to maintain
- * accuracy and to speed up calculations, i.e., the value need to be
- * divided by 16 to get the actual value.
- */
- int ave_beacon_signal;
+ struct ewma_beacon_signal ave_beacon_signal;
/*
* Number of Beacon frames used in ave_beacon_signal. This can be used
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index b4dd619da21e..cd705e820063 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -82,13 +82,6 @@ MODULE_PARM_DESC(probe_wait_ms,
" before disconnecting (reason 4).");
/*
- * Weight given to the latest Beacon frame when calculating average signal
- * strength for Beacon frames received in the current BSS. This must be
- * between 1 and 15.
- */
-#define IEEE80211_SIGNAL_AVE_WEIGHT 3
-
-/*
* How many Beacon frames need to have been used in average signal strength
* before starting to indicate signal change events.
*/
@@ -3376,21 +3369,19 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
/* Track average RSSI from the Beacon frames of the current AP */
if (ifmgd->flags & IEEE80211_STA_RESET_SIGNAL_AVE) {
ifmgd->flags &= ~IEEE80211_STA_RESET_SIGNAL_AVE;
- ifmgd->ave_beacon_signal = rx_status->signal * 16;
+ ewma_beacon_signal_init(&ifmgd->ave_beacon_signal);
ifmgd->last_cqm_event_signal = 0;
ifmgd->count_beacon_signal = 1;
ifmgd->last_ave_beacon_signal = 0;
} else {
- ifmgd->ave_beacon_signal =
- (IEEE80211_SIGNAL_AVE_WEIGHT * rx_status->signal * 16 +
- (16 - IEEE80211_SIGNAL_AVE_WEIGHT) *
- ifmgd->ave_beacon_signal) / 16;
ifmgd->count_beacon_signal++;
}
+ ewma_beacon_signal_add(&ifmgd->ave_beacon_signal, rx_status->signal);
+
if (ifmgd->rssi_min_thold != ifmgd->rssi_max_thold &&
ifmgd->count_beacon_signal >= IEEE80211_SIGNAL_AVE_MIN_COUNT) {
- int sig = ifmgd->ave_beacon_signal / 16;
+ int sig = ewma_beacon_signal_read(&ifmgd->ave_beacon_signal);
int last_sig = ifmgd->last_ave_beacon_signal;
struct ieee80211_event event = {
.type = RSSI_EVENT,
@@ -3417,10 +3408,11 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata,
if (bss_conf->cqm_rssi_thold &&
ifmgd->count_beacon_signal >= IEEE80211_SIGNAL_AVE_MIN_COUNT &&
!(sdata->vif.driver_flags & IEEE80211_VIF_SUPPORTS_CQM_RSSI)) {
- int sig = ifmgd->ave_beacon_signal / 16;
+ int sig = ewma_beacon_signal_read(&ifmgd->ave_beacon_signal);
int last_event = ifmgd->last_cqm_event_signal;
int thold = bss_conf->cqm_rssi_thold;
int hyst = bss_conf->cqm_rssi_hyst;
+
if (sig < thold &&
(last_event == 0 || sig < last_event - hyst)) {
ifmgd->last_cqm_event_signal = sig;
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 1104421bc525..e079b556a990 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -2541,7 +2541,7 @@ int ieee80211_ave_rssi(struct ieee80211_vif *vif)
/* non-managed type inferfaces */
return 0;
}
- return ifmgd->ave_beacon_signal / 16;
+ return ewma_beacon_signal_read(&ifmgd->ave_beacon_signal);
}
EXPORT_SYMBOL_GPL(ieee80211_ave_rssi);
--
2.1.4
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