From: Javier Cardona <[email protected]> The mesh metric is computed every time it was requested by the path selection framework. At that time only the last_tx_rate was taken into account when computing the metric. This last frame may not reflect the average data rate that was possible ver that peer link (it could be a management frame, a rate control probe, or other outlier).
This patch maintains an average tx rate for each peer link which is used in metric calculation. Signed-off-by: Javier Cardona <[email protected]> --- net/mac80211/mesh_hwmp.c | 24 +++++++++++++++--------- net/mac80211/sta_info.c | 1 + net/mac80211/sta_info.h | 1 + 3 files changed, 17 insertions(+), 9 deletions(-) diff --git a/net/mac80211/mesh_hwmp.c b/net/mac80211/mesh_hwmp.c index acbd1ad..8fb3e59 100644 --- a/net/mac80211/mesh_hwmp.c +++ b/net/mac80211/mesh_hwmp.c @@ -307,7 +307,9 @@ void ieee80211s_update_metric(struct ieee80211_local *local, { struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb); struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; + struct rate_info rinfo; int failed; + int rate; if (!ieee80211_is_data(hdr->frame_control)) return; @@ -318,36 +320,40 @@ void ieee80211s_update_metric(struct ieee80211_local *local, stainfo->fail_avg = ((80 * stainfo->fail_avg + 5) / 100 + 20 * failed); if (stainfo->fail_avg > 95) mesh_plink_broken(stainfo); + + sta_set_rate_info_tx(stainfo, &stainfo->last_tx_rate, &rinfo); + rate = cfg80211_calculate_bitrate(&rinfo); + if (WARN_ON(!rate)) + return; + + ewma_add(&stainfo->avg_rate, rate); + return; } static u32 airtime_link_metric_get(struct ieee80211_local *local, struct sta_info *sta) { - struct rate_info rinfo; /* This should be adjusted for each device */ int device_constant = 1 << ARITH_SHIFT; int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT; int s_unit = 1 << ARITH_SHIFT; - int rate, err; u32 tx_time, estimated_retx; u64 result; + int rate; + int err = (sta->fail_avg << ARITH_SHIFT) / 100; if (sta->fail_avg >= 100) return MAX_METRIC; - sta_set_rate_info_tx(sta, &sta->last_tx_rate, &rinfo); - rate = cfg80211_calculate_bitrate(&rinfo); - if (WARN_ON(!rate)) - return MAX_METRIC; - - err = (sta->fail_avg << ARITH_SHIFT) / 100; + /* If not enough values accumulated in rate average, assume 1 Mbps */ + rate = max(ewma_read(&sta->avg_rate), 10UL); /* bitrate is in units of 100 Kbps, while we need rate in units of * 1Mbps. This will be corrected on tx_time computation. */ tx_time = (device_constant + 10 * test_frame_len / rate); estimated_retx = ((1 << (2 * ARITH_SHIFT)) / (s_unit - err)); - result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT) ; + result = (tx_time * estimated_retx) >> (2 * ARITH_SHIFT); return (u32)result; } diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index 77dcf2f..ddbec7b 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -256,6 +256,7 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata, do_posix_clock_monotonic_gettime(&uptime); sta->last_connected = uptime.tv_sec; ewma_init(&sta->avg_signal, 1024, 8); + ewma_init(&sta->avg_rate, 1, 32); if (sta_prepare_rate_control(local, sta, gfp)) { kfree(sta); diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h index 3bb24a1..0bf888e 100644 --- a/net/mac80211/sta_info.h +++ b/net/mac80211/sta_info.h @@ -330,6 +330,7 @@ struct sta_info { unsigned long tx_retry_failed, tx_retry_count; /* moving percentage of failed MSDUs */ unsigned int fail_avg; + struct ewma avg_rate; /* Updated from TX path only, no locking requirements */ unsigned long tx_packets; -- 1.7.9.5 _______________________________________________ Devel mailing list [email protected] http://lists.open80211s.org/cgi-bin/mailman/listinfo/devel
