nl80211/mac80211: Report signal average

Extend nl80211 to report an exponential weighted moving average (EWMA) of the
signal value. Since the signal value usually fluctuates between different
packets, an average can be more useful than the value of the last packet.

This uses the recently added generic EWMA library function.

--
v2:	fix ABI breakage and change factor to be a power of 2.

Signed-off-by: Bruno Randolf <br1@einfach.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Bruno Randolf 2010-12-02 19:12:43 +09:00 committed by John W. Linville
parent 22de94de7d
commit 541a45a142
8 changed files with 18 additions and 1 deletions

View file

@ -1191,6 +1191,7 @@ enum nl80211_rate_info {
* station)
* @NL80211_STA_INFO_TX_RETRIES: total retries (u32, to this station)
* @NL80211_STA_INFO_TX_FAILED: total failed packets (u32, to this station)
* @NL80211_STA_INFO_SIGNAL_AVG: signal strength average (u8, dBm)
*/
enum nl80211_sta_info {
__NL80211_STA_INFO_INVALID,
@ -1206,6 +1207,7 @@ enum nl80211_sta_info {
NL80211_STA_INFO_TX_PACKETS,
NL80211_STA_INFO_TX_RETRIES,
NL80211_STA_INFO_TX_FAILED,
NL80211_STA_INFO_SIGNAL_AVG,
/* keep last */
__NL80211_STA_INFO_AFTER_LAST,

View file

@ -420,6 +420,7 @@ struct station_parameters {
* @STATION_INFO_TX_RETRIES: @tx_retries filled
* @STATION_INFO_TX_FAILED: @tx_failed filled
* @STATION_INFO_RX_DROP_MISC: @rx_dropped_misc filled
* @STATION_INFO_SIGNAL_AVG: @signal_avg filled
*/
enum station_info_flags {
STATION_INFO_INACTIVE_TIME = 1<<0,
@ -435,6 +436,7 @@ enum station_info_flags {
STATION_INFO_TX_RETRIES = 1<<10,
STATION_INFO_TX_FAILED = 1<<11,
STATION_INFO_RX_DROP_MISC = 1<<12,
STATION_INFO_SIGNAL_AVG = 1<<13,
};
/**
@ -481,6 +483,7 @@ struct rate_info {
* @plid: mesh peer link id
* @plink_state: mesh peer link state
* @signal: signal strength of last received packet in dBm
* @signal_avg: signal strength average in dBm
* @txrate: current unicast bitrate to this station
* @rx_packets: packets received from this station
* @tx_packets: packets transmitted to this station
@ -501,6 +504,7 @@ struct station_info {
u16 plid;
u8 plink_state;
s8 signal;
s8 signal_avg;
struct rate_info txrate;
u32 rx_packets;
u32 tx_packets;

View file

@ -6,6 +6,7 @@ config MAC80211
select CRYPTO_ARC4
select CRYPTO_AES
select CRC32
select AVERAGE
---help---
This option enables the hardware independent IEEE 802.11
networking stack.

View file

@ -342,8 +342,9 @@ static void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo)
if ((sta->local->hw.flags & IEEE80211_HW_SIGNAL_DBM) ||
(sta->local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC)) {
sinfo->filled |= STATION_INFO_SIGNAL;
sinfo->filled |= STATION_INFO_SIGNAL | STATION_INFO_SIGNAL_AVG;
sinfo->signal = (s8)sta->last_signal;
sinfo->signal_avg = (s8) -ewma_read(&sta->avg_signal);
}
sinfo->txrate.flags = 0;

View file

@ -1163,6 +1163,7 @@ ieee80211_rx_h_sta_process(struct ieee80211_rx_data *rx)
sta->rx_fragments++;
sta->rx_bytes += rx->skb->len;
sta->last_signal = status->signal;
ewma_add(&sta->avg_signal, -status->signal);
/*
* Change STA power saving mode only at the end of a frame

View file

@ -244,6 +244,8 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
sta->local = local;
sta->sdata = sdata;
ewma_init(&sta->avg_signal, 1024, 8);
if (sta_prepare_rate_control(local, sta, gfp)) {
kfree(sta);
return NULL;

View file

@ -13,6 +13,7 @@
#include <linux/types.h>
#include <linux/if_ether.h>
#include <linux/workqueue.h>
#include <linux/average.h>
#include "key.h"
/**
@ -223,6 +224,7 @@ enum plink_state {
* @rx_fragments: number of received MPDUs
* @rx_dropped: number of dropped MPDUs from this STA
* @last_signal: signal of last received frame from this STA
* @avg_signal: moving average of signal of received frames from this STA
* @last_seq_ctrl: last received seq/frag number from this STA (per RX queue)
* @tx_filtered_count: number of frames the hardware filtered for this STA
* @tx_retry_failed: number of frames that failed retry
@ -291,6 +293,7 @@ struct sta_info {
unsigned long rx_fragments;
unsigned long rx_dropped;
int last_signal;
struct ewma avg_signal;
__le16 last_seq_ctrl[NUM_RX_DATA_QUEUES];
/* Updated from TX status path only, no locking requirements */

View file

@ -1896,6 +1896,9 @@ static int nl80211_send_station(struct sk_buff *msg, u32 pid, u32 seq,
if (sinfo->filled & STATION_INFO_SIGNAL)
NLA_PUT_U8(msg, NL80211_STA_INFO_SIGNAL,
sinfo->signal);
if (sinfo->filled & STATION_INFO_SIGNAL_AVG)
NLA_PUT_U8(msg, NL80211_STA_INFO_SIGNAL_AVG,
sinfo->signal_avg);
if (sinfo->filled & STATION_INFO_TX_BITRATE) {
txrate = nla_nest_start(msg, NL80211_STA_INFO_TX_BITRATE);
if (!txrate)