Return-path: Received: from devils.ext.ti.com ([198.47.26.153]:47958 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932196AbcF3P22 (ORCPT ); Thu, 30 Jun 2016 11:28:28 -0400 From: Maxim Altshul To: CC: Maxim Altshul , Johannes Berg , "David S. Miller" , , Subject: [PATCH v2] mac80211: mesh: Add support for HW RC implementation Date: Thu, 30 Jun 2016 18:30:53 +0300 Message-ID: <20160630153055.26497-1-maxim.altshul@ti.com> (sfid-20160630_172904_813448_E5A37DB0) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: Mesh HWMP module will be able to rely on the HW RC algorithm if it exists, for path metric calculations. This allows the metric calculation mechanism to calculate a correct metric, based on PER and last TX rate both via HW RC algorithm if it exists or via parameters collected by the SW. Signed-off-by: Maxim Altshul --- Changed the function to return u32, I agree that this is much clearer. As for the rate, two things: 1. I had to divide the returned value by 100, since drv_get_expected_throughput returns values in units of Kbps. On the contrary, the function cfg80211_calculate_bitrate returns in units of 100Kbps, so a correction is needed. 2. Why return the value into rate? As I understand, rate here is actually bitrate, and so, we have two possible outcomes: - A SW/HW RC algo does exist, and an estimated throughput is returned. err is set to 0 (as it is already included in the RC algo) and the airtime is calculated using the estimated throughput. - A SW/HW RC algo does not exist, and thus the regular calculation takes place, in which an estimated throughput is calculated using the bitrate and the err parameter. >From this calculation the airtime is calculated. net/mac80211/mesh_hwmp.c | 25 +++++++++++++++++-------- net/mac80211/sta_info.c | 23 +++++++++++++++++++---- net/mac80211/sta_info.h | 2 ++ 3 files changed, 38 insertions(+), 12 deletions(-) diff --git a/net/mac80211/mesh_hwmp.c b/net/mac80211/mesh_hwmp.c index c6be0b4..ad67f46 100644 --- a/net/mac80211/mesh_hwmp.c +++ b/net/mac80211/mesh_hwmp.c @@ -322,19 +322,28 @@ static u32 airtime_link_metric_get(struct ieee80211_local *local, int device_constant = 1 << ARITH_SHIFT; int test_frame_len = TEST_FRAME_LEN << ARITH_SHIFT; int s_unit = 1 << ARITH_SHIFT; - int rate, err; + int rate = 0, err = 0; u32 tx_time, estimated_retx; u64 result; - if (sta->mesh->fail_avg >= 100) - return MAX_METRIC; + /* Try to get rate based on HW/SW RC algorithm. + * Rate is returned in units of Kbps, correct this + * to comply with airtime calculation units + */ + rate = sta_get_expected_throughput(sta) / 100; + + /* if we did not get a rate */ + if (!rate) { + if (sta->mesh->fail_avg >= 100) + return MAX_METRIC; - sta_set_rate_info_tx(sta, &sta->tx_stats.last_rate, &rinfo); - rate = cfg80211_calculate_bitrate(&rinfo); - if (WARN_ON(!rate)) - return MAX_METRIC; + sta_set_rate_info_tx(sta, &sta->tx_stats.last_rate, &rinfo); + rate = cfg80211_calculate_bitrate(&rinfo); + if (WARN_ON(!rate)) + return MAX_METRIC; - err = (sta->mesh->fail_avg << ARITH_SHIFT) / 100; + err = (sta->mesh->fail_avg << ARITH_SHIFT) / 100; + } /* bitrate is in units of 100 Kbps, while we need rate in units of * 1Mbps. This will be corrected on tx_time computation. diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index 63ea6cb..fa2c507 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -2069,14 +2069,29 @@ void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo) if (test_sta_flag(sta, WLAN_STA_TDLS_PEER)) sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_TDLS_PEER); + thr = sta_get_expected_throughput(sta); + + if (thr != 0) { + sinfo->filled |= BIT(NL80211_STA_INFO_EXPECTED_THROUGHPUT); + sinfo->expected_throughput = thr; + } +} + +u32 sta_get_expected_throughput(struct sta_info *sta) +{ + struct ieee80211_sub_if_data *sdata = sta->sdata; + struct ieee80211_local *local = sdata->local; + struct rate_control_ref *ref = NULL; + u32 thr = 0; + + if (test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) + ref = local->rate_ctrl; + /* check if the driver has a SW RC implementation */ if (ref && ref->ops->get_expected_throughput) thr = ref->ops->get_expected_throughput(sta->rate_ctrl_priv); else thr = drv_get_expected_throughput(local, &sta->sta); - if (thr != 0) { - sinfo->filled |= BIT(NL80211_STA_INFO_EXPECTED_THROUGHPUT); - sinfo->expected_throughput = thr; - } + return thr; } diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h index 2cafb21..5c9c8be 100644 --- a/net/mac80211/sta_info.h +++ b/net/mac80211/sta_info.h @@ -661,6 +661,8 @@ void sta_set_rate_info_tx(struct sta_info *sta, struct rate_info *rinfo); void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo); +u32 sta_get_expected_throughput(struct sta_info *sta); + void ieee80211_sta_expire(struct ieee80211_sub_if_data *sdata, unsigned long exp_time); u8 sta_info_tx_streams(struct sta_info *sta); -- 2.9.0