[v4,3/6] mac80211: Add airtime accounting and scheduling to TXQs
diff mbox series

Message ID 1545172374-1072-4-git-send-email-rmanohar@codeaurora.org
State New
Headers show
Series
  • Move TXQ scheduling and airtime fairness into mac80211
Related show

Commit Message

Rajkumar Manoharan Dec. 18, 2018, 10:32 p.m. UTC
From: Toke Høiland-Jørgensen <toke@toke.dk>

This adds airtime accounting and scheduling to the mac80211 TXQ
scheduler. A new callback, ieee80211_sta_register_airtime(), is added
that drivers can call to report airtime usage for stations.

When airtime information is present, mac80211 will schedule TXQs
(through ieee80211_next_txq()) in a way that enforces airtime fairness
between active stations. This scheduling works the same way as the ath9k
in-driver airtime fairness scheduling. If no airtime usage is reported
by the driver, the scheduler will default to round-robin scheduling.

For drivers that don't control TXQ scheduling in software, a new API
function, ieee80211_txq_may_transmit(), is added which the driver can use
to check if the TXQ is eligible for transmission, or should be throttled to
enforce fairness. Calls to this function must also be enclosed in
ieee80211_txq_schedule_{start,end}() calls to ensure proper locking.

The API ieee80211_txq_may_transmit() also ensures that TXQ list will be
aligned aginst driver's own round-robin scheduler list. i.e it rotates
the TXQ list till it makes the requested node becomes the first entry
in TXQ list. Thus both the TXQ list and driver's list are in sync.

Co-developed-by: Rajkumar Manoharan <rmanohar@codeaurora.org>
Signed-off-by: Louie Lu <git@louie.lu>
[added debugfs write op to reset airtime counter]
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Rajkumar Manoharan <rmanohar@codeaurora.org>
---
 include/net/mac80211.h     | 59 ++++++++++++++++++++++++++++++
 net/mac80211/cfg.c         |  3 ++
 net/mac80211/debugfs.c     |  3 ++
 net/mac80211/debugfs_sta.c | 68 +++++++++++++++++++++++++++++++++--
 net/mac80211/ieee80211_i.h |  2 ++
 net/mac80211/main.c        |  4 +++
 net/mac80211/sta_info.c    | 44 +++++++++++++++++++++--
 net/mac80211/sta_info.h    | 13 +++++++
 net/mac80211/status.c      |  6 ++++
 net/mac80211/tx.c          | 90 +++++++++++++++++++++++++++++++++++++++++++---
 10 files changed, 282 insertions(+), 10 deletions(-)

Comments

kbuild test robot Dec. 19, 2018, 12:47 a.m. UTC | #1
Hi Toke,

I love your patch! Perhaps something to improve:

[auto build test WARNING on mac80211/master]
[also build test WARNING on v4.20-rc7]
[cannot apply to next-20181218]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Rajkumar-Manoharan/Move-TXQ-scheduling-and-airtime-fairness-into-mac80211/20181219-080126
base:   https://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211.git master
config: i386-randconfig-x001-201850 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
        # save the attached .config to linux build tree
        make ARCH=i386 

All warnings (new ones prefixed by >>):

   In file included from include/linux/bitops.h:5:0,
                    from include/linux/kernel.h:11,
                    from include/linux/list.h:9,
                    from include/linux/module.h:9,
                    from net/mac80211/sta_info.c:13:
   net/mac80211/sta_info.c: In function 'sta_set_sinfo':
   include/linux/bits.h:6:24: warning: left shift count >= width of type [-Wshift-count-overflow]
    #define BIT(nr)   (1UL << (nr))
                           ^
>> net/mac80211/sta_info.c:2215:20: note: in expansion of macro 'BIT'
      sinfo->filled |= BIT(NL80211_STA_INFO_RX_DURATION);
                       ^~~
   include/linux/bits.h:6:24: warning: left shift count >= width of type [-Wshift-count-overflow]
    #define BIT(nr)   (1UL << (nr))
                           ^
   net/mac80211/sta_info.c:2221:20: note: in expansion of macro 'BIT'
      sinfo->filled |= BIT(NL80211_STA_INFO_TX_DURATION);
                       ^~~
   include/linux/bits.h:6:24: warning: left shift count >= width of type [-Wshift-count-overflow]
    #define BIT(nr)   (1UL << (nr))
                           ^
   net/mac80211/sta_info.c:2226:20: note: in expansion of macro 'BIT'
      sinfo->filled |= BIT(NL80211_STA_INFO_AIRTIME_WEIGHT);
                       ^~~

vim +/BIT +2215 net/mac80211/sta_info.c

  2120	
  2121	void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo,
  2122			   bool tidstats)
  2123	{
  2124		struct ieee80211_sub_if_data *sdata = sta->sdata;
  2125		struct ieee80211_local *local = sdata->local;
  2126		u32 thr = 0;
  2127		int i, ac, cpu;
  2128		struct ieee80211_sta_rx_stats *last_rxstats;
  2129	
  2130		last_rxstats = sta_get_last_rx_stats(sta);
  2131	
  2132		sinfo->generation = sdata->local->sta_generation;
  2133	
  2134		/* do before driver, so beacon filtering drivers have a
  2135		 * chance to e.g. just add the number of filtered beacons
  2136		 * (or just modify the value entirely, of course)
  2137		 */
  2138		if (sdata->vif.type == NL80211_IFTYPE_STATION)
  2139			sinfo->rx_beacon = sdata->u.mgd.count_beacon_signal;
  2140	
  2141		drv_sta_statistics(local, sdata, &sta->sta, sinfo);
  2142	
  2143		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_INACTIVE_TIME) |
  2144				 BIT_ULL(NL80211_STA_INFO_STA_FLAGS) |
  2145				 BIT_ULL(NL80211_STA_INFO_BSS_PARAM) |
  2146				 BIT_ULL(NL80211_STA_INFO_CONNECTED_TIME) |
  2147				 BIT_ULL(NL80211_STA_INFO_RX_DROP_MISC);
  2148	
  2149		if (sdata->vif.type == NL80211_IFTYPE_STATION) {
  2150			sinfo->beacon_loss_count = sdata->u.mgd.beacon_loss_count;
  2151			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_BEACON_LOSS);
  2152		}
  2153	
  2154		sinfo->connected_time = ktime_get_seconds() - sta->last_connected;
  2155		sinfo->inactive_time =
  2156			jiffies_to_msecs(jiffies - ieee80211_sta_last_active(sta));
  2157	
  2158		if (!(sinfo->filled & (BIT_ULL(NL80211_STA_INFO_TX_BYTES64) |
  2159				       BIT_ULL(NL80211_STA_INFO_TX_BYTES)))) {
  2160			sinfo->tx_bytes = 0;
  2161			for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
  2162				sinfo->tx_bytes += sta->tx_stats.bytes[ac];
  2163			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_BYTES64);
  2164		}
  2165	
  2166		if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_PACKETS))) {
  2167			sinfo->tx_packets = 0;
  2168			for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
  2169				sinfo->tx_packets += sta->tx_stats.packets[ac];
  2170			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_PACKETS);
  2171		}
  2172	
  2173		if (!(sinfo->filled & (BIT_ULL(NL80211_STA_INFO_RX_BYTES64) |
  2174				       BIT_ULL(NL80211_STA_INFO_RX_BYTES)))) {
  2175			sinfo->rx_bytes += sta_get_stats_bytes(&sta->rx_stats);
  2176	
  2177			if (sta->pcpu_rx_stats) {
  2178				for_each_possible_cpu(cpu) {
  2179					struct ieee80211_sta_rx_stats *cpurxs;
  2180	
  2181					cpurxs = per_cpu_ptr(sta->pcpu_rx_stats, cpu);
  2182					sinfo->rx_bytes += sta_get_stats_bytes(cpurxs);
  2183				}
  2184			}
  2185	
  2186			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_RX_BYTES64);
  2187		}
  2188	
  2189		if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_RX_PACKETS))) {
  2190			sinfo->rx_packets = sta->rx_stats.packets;
  2191			if (sta->pcpu_rx_stats) {
  2192				for_each_possible_cpu(cpu) {
  2193					struct ieee80211_sta_rx_stats *cpurxs;
  2194	
  2195					cpurxs = per_cpu_ptr(sta->pcpu_rx_stats, cpu);
  2196					sinfo->rx_packets += cpurxs->packets;
  2197				}
  2198			}
  2199			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_RX_PACKETS);
  2200		}
  2201	
  2202		if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_RETRIES))) {
  2203			sinfo->tx_retries = sta->status_stats.retry_count;
  2204			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_RETRIES);
  2205		}
  2206	
  2207		if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_FAILED))) {
  2208			sinfo->tx_failed = sta->status_stats.retry_failed;
  2209			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_FAILED);
  2210		}
  2211	
  2212		if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_RX_DURATION))) {
  2213			for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
  2214				sinfo->rx_duration += sta->airtime[ac].rx_airtime;
> 2215			sinfo->filled |= BIT(NL80211_STA_INFO_RX_DURATION);
  2216		}
  2217	
  2218		if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_DURATION))) {
  2219			for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
  2220				sinfo->tx_duration += sta->airtime[ac].tx_airtime;
  2221			sinfo->filled |= BIT(NL80211_STA_INFO_TX_DURATION);
  2222		}
  2223	
  2224		if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_AIRTIME_WEIGHT))) {
  2225			sinfo->airtime_weight = sta->airtime_weight;
  2226			sinfo->filled |= BIT(NL80211_STA_INFO_AIRTIME_WEIGHT);
  2227		}
  2228	
  2229		sinfo->rx_dropped_misc = sta->rx_stats.dropped;
  2230		if (sta->pcpu_rx_stats) {
  2231			for_each_possible_cpu(cpu) {
  2232				struct ieee80211_sta_rx_stats *cpurxs;
  2233	
  2234				cpurxs = per_cpu_ptr(sta->pcpu_rx_stats, cpu);
  2235				sinfo->rx_dropped_misc += cpurxs->dropped;
  2236			}
  2237		}
  2238	
  2239		if (sdata->vif.type == NL80211_IFTYPE_STATION &&
  2240		    !(sdata->vif.driver_flags & IEEE80211_VIF_BEACON_FILTER)) {
  2241			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_BEACON_RX) |
  2242					 BIT_ULL(NL80211_STA_INFO_BEACON_SIGNAL_AVG);
  2243			sinfo->rx_beacon_signal_avg = ieee80211_ave_rssi(&sdata->vif);
  2244		}
  2245	
  2246		if (ieee80211_hw_check(&sta->local->hw, SIGNAL_DBM) ||
  2247		    ieee80211_hw_check(&sta->local->hw, SIGNAL_UNSPEC)) {
  2248			if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_SIGNAL))) {
  2249				sinfo->signal = (s8)last_rxstats->last_signal;
  2250				sinfo->filled |= BIT_ULL(NL80211_STA_INFO_SIGNAL);
  2251			}
  2252	
  2253			if (!sta->pcpu_rx_stats &&
  2254			    !(sinfo->filled & BIT_ULL(NL80211_STA_INFO_SIGNAL_AVG))) {
  2255				sinfo->signal_avg =
  2256					-ewma_signal_read(&sta->rx_stats_avg.signal);
  2257				sinfo->filled |= BIT_ULL(NL80211_STA_INFO_SIGNAL_AVG);
  2258			}
  2259		}
  2260	
  2261		/* for the average - if pcpu_rx_stats isn't set - rxstats must point to
  2262		 * the sta->rx_stats struct, so the check here is fine with and without
  2263		 * pcpu statistics
  2264		 */
  2265		if (last_rxstats->chains &&
  2266		    !(sinfo->filled & (BIT_ULL(NL80211_STA_INFO_CHAIN_SIGNAL) |
  2267				       BIT_ULL(NL80211_STA_INFO_CHAIN_SIGNAL_AVG)))) {
  2268			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_CHAIN_SIGNAL);
  2269			if (!sta->pcpu_rx_stats)
  2270				sinfo->filled |= BIT_ULL(NL80211_STA_INFO_CHAIN_SIGNAL_AVG);
  2271	
  2272			sinfo->chains = last_rxstats->chains;
  2273	
  2274			for (i = 0; i < ARRAY_SIZE(sinfo->chain_signal); i++) {
  2275				sinfo->chain_signal[i] =
  2276					last_rxstats->chain_signal_last[i];
  2277				sinfo->chain_signal_avg[i] =
  2278					-ewma_signal_read(&sta->rx_stats_avg.chain_signal[i]);
  2279			}
  2280		}
  2281	
  2282		if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_BITRATE))) {
  2283			sta_set_rate_info_tx(sta, &sta->tx_stats.last_rate,
  2284					     &sinfo->txrate);
  2285			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_BITRATE);
  2286		}
  2287	
  2288		if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_RX_BITRATE))) {
  2289			if (sta_set_rate_info_rx(sta, &sinfo->rxrate) == 0)
  2290				sinfo->filled |= BIT_ULL(NL80211_STA_INFO_RX_BITRATE);
  2291		}
  2292	
  2293		if (tidstats && !cfg80211_sinfo_alloc_tid_stats(sinfo, GFP_KERNEL)) {
  2294			for (i = 0; i < IEEE80211_NUM_TIDS + 1; i++) {
  2295				struct cfg80211_tid_stats *tidstats = &sinfo->pertid[i];
  2296	
  2297				sta_set_tidstats(sta, tidstats, i);
  2298			}
  2299		}
  2300	
  2301		if (ieee80211_vif_is_mesh(&sdata->vif)) {
  2302	#ifdef CONFIG_MAC80211_MESH
  2303			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_LLID) |
  2304					 BIT_ULL(NL80211_STA_INFO_PLID) |
  2305					 BIT_ULL(NL80211_STA_INFO_PLINK_STATE) |
  2306					 BIT_ULL(NL80211_STA_INFO_LOCAL_PM) |
  2307					 BIT_ULL(NL80211_STA_INFO_PEER_PM) |
  2308					 BIT_ULL(NL80211_STA_INFO_NONPEER_PM);
  2309	
  2310			sinfo->llid = sta->mesh->llid;
  2311			sinfo->plid = sta->mesh->plid;
  2312			sinfo->plink_state = sta->mesh->plink_state;
  2313			if (test_sta_flag(sta, WLAN_STA_TOFFSET_KNOWN)) {
  2314				sinfo->filled |= BIT_ULL(NL80211_STA_INFO_T_OFFSET);
  2315				sinfo->t_offset = sta->mesh->t_offset;
  2316			}
  2317			sinfo->local_pm = sta->mesh->local_pm;
  2318			sinfo->peer_pm = sta->mesh->peer_pm;
  2319			sinfo->nonpeer_pm = sta->mesh->nonpeer_pm;
  2320	#endif
  2321		}
  2322	
  2323		sinfo->bss_param.flags = 0;
  2324		if (sdata->vif.bss_conf.use_cts_prot)
  2325			sinfo->bss_param.flags |= BSS_PARAM_FLAGS_CTS_PROT;
  2326		if (sdata->vif.bss_conf.use_short_preamble)
  2327			sinfo->bss_param.flags |= BSS_PARAM_FLAGS_SHORT_PREAMBLE;
  2328		if (sdata->vif.bss_conf.use_short_slot)
  2329			sinfo->bss_param.flags |= BSS_PARAM_FLAGS_SHORT_SLOT_TIME;
  2330		sinfo->bss_param.dtim_period = sdata->vif.bss_conf.dtim_period;
  2331		sinfo->bss_param.beacon_interval = sdata->vif.bss_conf.beacon_int;
  2332	
  2333		sinfo->sta_flags.set = 0;
  2334		sinfo->sta_flags.mask = BIT(NL80211_STA_FLAG_AUTHORIZED) |
  2335					BIT(NL80211_STA_FLAG_SHORT_PREAMBLE) |
  2336					BIT(NL80211_STA_FLAG_WME) |
  2337					BIT(NL80211_STA_FLAG_MFP) |
  2338					BIT(NL80211_STA_FLAG_AUTHENTICATED) |
  2339					BIT(NL80211_STA_FLAG_ASSOCIATED) |
  2340					BIT(NL80211_STA_FLAG_TDLS_PEER);
  2341		if (test_sta_flag(sta, WLAN_STA_AUTHORIZED))
  2342			sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_AUTHORIZED);
  2343		if (test_sta_flag(sta, WLAN_STA_SHORT_PREAMBLE))
  2344			sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_SHORT_PREAMBLE);
  2345		if (sta->sta.wme)
  2346			sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_WME);
  2347		if (test_sta_flag(sta, WLAN_STA_MFP))
  2348			sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_MFP);
  2349		if (test_sta_flag(sta, WLAN_STA_AUTH))
  2350			sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_AUTHENTICATED);
  2351		if (test_sta_flag(sta, WLAN_STA_ASSOC))
  2352			sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_ASSOCIATED);
  2353		if (test_sta_flag(sta, WLAN_STA_TDLS_PEER))
  2354			sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_TDLS_PEER);
  2355	
  2356		thr = sta_get_expected_throughput(sta);
  2357	
  2358		if (thr != 0) {
  2359			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_EXPECTED_THROUGHPUT);
  2360			sinfo->expected_throughput = thr;
  2361		}
  2362	
  2363		if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_ACK_SIGNAL)) &&
  2364		    sta->status_stats.ack_signal_filled) {
  2365			sinfo->ack_signal = sta->status_stats.last_ack_signal;
  2366			sinfo->filled |= BIT_ULL(NL80211_STA_INFO_ACK_SIGNAL);
  2367		}
  2368	
  2369		if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_ACK_SIGNAL_AVG)) &&
  2370		    sta->status_stats.ack_signal_filled) {
  2371			sinfo->avg_ack_signal =
  2372				-(s8)ewma_avg_signal_read(
  2373					&sta->status_stats.avg_ack_signal);
  2374			sinfo->filled |=
  2375				BIT_ULL(NL80211_STA_INFO_ACK_SIGNAL_AVG);
  2376		}
  2377	}
  2378	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

Patch
diff mbox series

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 18b11c119b7e..c43d615ee9b1 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -2357,6 +2357,9 @@  enum ieee80211_hw_flags {
  * @tx_sk_pacing_shift: Pacing shift to set on TCP sockets when frames from
  *	them are encountered. The default should typically not be changed,
  *	unless the driver has good reasons for needing more buffers.
+ *
+ * @weight_multipler: Driver specific airtime weight multiplier used while
+ *	refilling deficit of each TXQ.
  */
 struct ieee80211_hw {
 	struct ieee80211_conf conf;
@@ -2393,6 +2396,7 @@  struct ieee80211_hw {
 	const struct ieee80211_cipher_scheme *cipher_schemes;
 	u8 max_nan_de_entries;
 	u8 tx_sk_pacing_shift;
+	u8 weight_multiplier;
 };
 
 static inline bool _ieee80211_hw_check(struct ieee80211_hw *hw,
@@ -5393,6 +5397,34 @@  void ieee80211_sta_block_awake(struct ieee80211_hw *hw,
 void ieee80211_send_eosp_nullfunc(struct ieee80211_sta *pubsta, int tid);
 
 /**
+ * ieee80211_sta_register_airtime - register airtime usage for a sta/tid
+ *
+ * Register airtime usage for a given sta on a given tid. The driver can call
+ * this function to notify mac80211 that a station used a certain amount of
+ * airtime. This information will be used by the TXQ scheduler to schedule
+ * stations in a way that ensures airtime fairness.
+ *
+ * The reported airtime should as a minimum include all time that is spent
+ * transmitting to the remote station, including overhead and padding, but not
+ * including time spent waiting for a TXOP. If the time is not reported by the
+ * hardware it can in some cases be calculated from the rate and known frame
+ * composition. When possible, the time should include any failed transmission
+ * attempts.
+ *
+ * The driver can either call this function synchronously for every packet or
+ * aggregate, or asynchronously as airtime usage information becomes available.
+ * TX and RX airtime can be reported together, or separately by setting one of
+ * them to 0.
+ *
+ * @pubsta: the station
+ * @tid: the TID to register airtime for
+ * @tx_airtime: airtime used during TX (in usec)
+ * @rx_airtime: airtime used during RX (in usec)
+ */
+void ieee80211_sta_register_airtime(struct ieee80211_sta *pubsta, u8 tid,
+				    u32 tx_airtime, u32 rx_airtime);
+
+/**
  * ieee80211_iter_keys - iterate keys programmed into the device
  * @hw: pointer obtained from ieee80211_alloc_hw()
  * @vif: virtual interface to iterate, may be %NULL for all
@@ -6150,6 +6182,33 @@  struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw,
 void ieee80211_txq_schedule_end(struct ieee80211_hw *hw, u8 ac);
 
 /**
+ * ieee80211_txq_may_transmit - check whether TXQ is allowed to transmit
+ *
+ * This function is used to check whether given txq is allowed to transmit by
+ * the airtime scheduler, and can be used by drivers to access the airtime
+ * fairness accounting without going using the scheduling order enfored by
+ * next_txq().
+ *
+ * Returns %true if the airtime scheduler thinks the TXQ should be allowed to
+ * transmit, and %false if it should be throttled. This function can also have
+ * the side effect of rotating the TXQ in the scheduler rotation, which will
+ * eventually bring the deficit to positive and allow the station to transmit
+ * again.
+ *
+ * The API ieee80211_txq_may_transmit() also ensures that TXQ list will be
+ * aligned aginst driver's own round-robin scheduler list. i.e it rotates
+ * the TXQ list till it makes the requested node becomes the first entry
+ * in TXQ list. Thus both the TXQ list and driver's list are in sync. If this
+ * function returns %true, the driver is expected to schedule packets
+ * for transmission, and then return the TXQ through ieee80211_return_txq().
+ *
+ * @hw: pointer as obtained from ieee80211_alloc_hw()
+ * @txq: pointer obtained from station or virtual interface
+ */
+bool ieee80211_txq_may_transmit(struct ieee80211_hw *hw,
+				struct ieee80211_txq *txq);
+
+/**
  * ieee80211_txq_get_depth - get pending frame/byte count of given txq
  *
  * The values are not guaranteed to be coherent with regard to each other, i.e.
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 818aa0060349..57c59e5ceb98 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -1447,6 +1447,9 @@  static int sta_apply_parameters(struct ieee80211_local *local,
 	if (ieee80211_vif_is_mesh(&sdata->vif))
 		sta_apply_mesh_params(local, sta, params);
 
+	if (params->airtime_weight)
+		sta->airtime_weight = params->airtime_weight;
+
 	/* set the STA state after all sta info from usermode has been set */
 	if (test_sta_flag(sta, WLAN_STA_TDLS_PEER) ||
 	    set & BIT(NL80211_STA_FLAG_ASSOCIATED)) {
diff --git a/net/mac80211/debugfs.c b/net/mac80211/debugfs.c
index 3fe541e358f3..81c5fec2eae7 100644
--- a/net/mac80211/debugfs.c
+++ b/net/mac80211/debugfs.c
@@ -383,6 +383,9 @@  void debugfs_hw_add(struct ieee80211_local *local)
 	if (local->ops->wake_tx_queue)
 		DEBUGFS_ADD_MODE(aqm, 0600);
 
+	debugfs_create_u16("airtime_flags", 0600,
+			   phyd, &local->airtime_flags);
+
 	statsd = debugfs_create_dir("statistics", phyd);
 
 	/* if the dir failed, don't put all the other things into the root! */
diff --git a/net/mac80211/debugfs_sta.c b/net/mac80211/debugfs_sta.c
index af5185a836e5..b9686147a8b0 100644
--- a/net/mac80211/debugfs_sta.c
+++ b/net/mac80211/debugfs_sta.c
@@ -181,9 +181,9 @@  static ssize_t sta_aqm_read(struct file *file, char __user *userbuf,
 			       txqi->tin.tx_bytes,
 			       txqi->tin.tx_packets,
 			       txqi->flags,
-			       txqi->flags & (1<<IEEE80211_TXQ_STOP) ? "STOP" : "RUN",
-			       txqi->flags & (1<<IEEE80211_TXQ_AMPDU) ? " AMPDU" : "",
-			       txqi->flags & (1<<IEEE80211_TXQ_NO_AMSDU) ? " NO-AMSDU" : "");
+			       test_bit(IEEE80211_TXQ_STOP, &txqi->flags) ? "STOP" : "RUN",
+			       test_bit(IEEE80211_TXQ_AMPDU, &txqi->flags) ? " AMPDU" : "",
+			       test_bit(IEEE80211_TXQ_NO_AMSDU, &txqi->flags) ? " NO-AMSDU" : "");
 	}
 
 	rcu_read_unlock();
@@ -195,6 +195,64 @@  static ssize_t sta_aqm_read(struct file *file, char __user *userbuf,
 }
 STA_OPS(aqm);
 
+static ssize_t sta_airtime_read(struct file *file, char __user *userbuf,
+				size_t count, loff_t *ppos)
+{
+	struct sta_info *sta = file->private_data;
+	struct ieee80211_local *local = sta->sdata->local;
+	size_t bufsz = 200;
+	char *buf = kzalloc(bufsz, GFP_KERNEL), *p = buf;
+	u64 rx_airtime = 0, tx_airtime = 0;
+	s64 deficit[IEEE80211_NUM_ACS];
+	ssize_t rv;
+	int ac;
+
+	if (!buf)
+		return -ENOMEM;
+
+	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
+		spin_lock_bh(&local->active_txq_lock[ac]);
+		rx_airtime += sta->airtime[ac].rx_airtime;
+		tx_airtime += sta->airtime[ac].tx_airtime;
+		deficit[ac] = sta->airtime[ac].deficit;
+		spin_unlock_bh(&local->active_txq_lock[ac]);
+	}
+
+	p += scnprintf(p, bufsz + buf - p,
+		"RX: %llu us\nTX: %llu us\nWeight: %u\n"
+		"Deficit: VO: %lld us VI: %lld us BE: %lld us BK: %lld us\n",
+		rx_airtime,
+		tx_airtime,
+		sta->airtime_weight,
+		deficit[0],
+		deficit[1],
+		deficit[2],
+		deficit[3]);
+
+	rv = simple_read_from_buffer(userbuf, count, ppos, buf, p - buf);
+	kfree(buf);
+	return rv;
+}
+
+static ssize_t sta_airtime_write(struct file *file, const char __user *userbuf,
+				 size_t count, loff_t *ppos)
+{
+	struct sta_info *sta = file->private_data;
+	struct ieee80211_local *local = sta->sdata->local;
+	int ac;
+
+	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
+		spin_lock_bh(&local->active_txq_lock[ac]);
+		sta->airtime[ac].rx_airtime = 0;
+		sta->airtime[ac].tx_airtime = 0;
+		sta->airtime[ac].deficit = sta->airtime_weight;
+		spin_unlock_bh(&local->active_txq_lock[ac]);
+	}
+
+	return count;
+}
+STA_OPS_RW(airtime);
+
 static ssize_t sta_agg_status_read(struct file *file, char __user *userbuf,
 					size_t count, loff_t *ppos)
 {
@@ -906,6 +964,10 @@  void ieee80211_sta_debugfs_add(struct sta_info *sta)
 	if (local->ops->wake_tx_queue)
 		DEBUGFS_ADD(aqm);
 
+	if (wiphy_ext_feature_isset(local->hw.wiphy,
+				    NL80211_EXT_FEATURE_AIRTIME_FAIRNESS))
+		DEBUGFS_ADD(airtime);
+
 	if (sizeof(sta->driver_buffered_tids) == sizeof(u32))
 		debugfs_create_x32("driver_buffered_tids", 0400,
 				   sta->debugfs_dir,
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 33763a2eac81..c5b6ba571288 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1137,6 +1137,8 @@  struct ieee80211_local {
 	struct list_head active_txqs[IEEE80211_NUM_ACS];
 	u16 schedule_round[IEEE80211_NUM_ACS];
 
+	u16 airtime_flags;
+
 	const struct ieee80211_ops *ops;
 
 	/*
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index 5d292ef0a544..d6e19b7a0725 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -667,6 +667,7 @@  struct ieee80211_hw *ieee80211_alloc_hw_nm(size_t priv_data_len,
 		INIT_LIST_HEAD(&local->active_txqs[i]);
 		spin_lock_init(&local->active_txq_lock[i]);
 	}
+	local->airtime_flags = AIRTIME_USE_TX | AIRTIME_USE_RX;
 
 	INIT_LIST_HEAD(&local->chanctx_list);
 	mutex_init(&local->chanctx_mtx);
@@ -1153,6 +1154,9 @@  int ieee80211_register_hw(struct ieee80211_hw *hw)
 	if (!local->hw.max_nan_de_entries)
 		local->hw.max_nan_de_entries = IEEE80211_MAX_NAN_INSTANCE_ID;
 
+	if (!local->hw.weight_multiplier)
+		local->hw.weight_multiplier = 1;
+
 	result = ieee80211_wep_init(local);
 	if (result < 0)
 		wiphy_debug(local->hw.wiphy, "Failed to initialize wep: %d\n",
diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index c2f5cb7df54f..25d47b2af7a9 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -90,7 +90,6 @@  static void __cleanup_single_sta(struct sta_info *sta)
 	struct tid_ampdu_tx *tid_tx;
 	struct ieee80211_sub_if_data *sdata = sta->sdata;
 	struct ieee80211_local *local = sdata->local;
-	struct fq *fq = &local->fq;
 	struct ps_data *ps;
 
 	if (test_sta_flag(sta, WLAN_STA_PS_STA) ||
@@ -120,9 +119,7 @@  static void __cleanup_single_sta(struct sta_info *sta)
 
 			txqi = to_txq_info(sta->sta.txq[i]);
 
-			spin_lock_bh(&fq->lock);
 			ieee80211_txq_purge(local, txqi);
-			spin_unlock_bh(&fq->lock);
 		}
 	}
 
@@ -387,9 +384,12 @@  struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
 	if (sta_prepare_rate_control(local, sta, gfp))
 		goto free_txq;
 
+	sta->airtime_weight = IEEE80211_DEFAULT_AIRTIME_WEIGHT;
+
 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
 		skb_queue_head_init(&sta->ps_tx_buf[i]);
 		skb_queue_head_init(&sta->tx_filtered[i]);
+		sta->airtime[i].deficit = sta->airtime_weight;
 	}
 
 	for (i = 0; i < IEEE80211_NUM_TIDS; i++)
@@ -1826,6 +1826,27 @@  void ieee80211_sta_set_buffered(struct ieee80211_sta *pubsta,
 }
 EXPORT_SYMBOL(ieee80211_sta_set_buffered);
 
+void ieee80211_sta_register_airtime(struct ieee80211_sta *pubsta, u8 tid,
+				    u32 tx_airtime, u32 rx_airtime)
+{
+	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
+	struct ieee80211_local *local = sta->sdata->local;
+	u8 ac = ieee80211_ac_from_tid(tid);
+	u32 airtime = 0;
+
+	if (sta->local->airtime_flags & AIRTIME_USE_TX)
+		airtime += tx_airtime;
+	if (sta->local->airtime_flags & AIRTIME_USE_RX)
+		airtime += rx_airtime;
+
+	spin_lock_bh(&local->active_txq_lock[ac]);
+	sta->airtime[ac].tx_airtime += tx_airtime;
+	sta->airtime[ac].rx_airtime += rx_airtime;
+	sta->airtime[ac].deficit -= airtime;
+	spin_unlock_bh(&local->active_txq_lock[ac]);
+}
+EXPORT_SYMBOL(ieee80211_sta_register_airtime);
+
 int sta_info_move_state(struct sta_info *sta,
 			enum ieee80211_sta_state new_state)
 {
@@ -2188,6 +2209,23 @@  void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo,
 		sinfo->filled |= BIT_ULL(NL80211_STA_INFO_TX_FAILED);
 	}
 
+	if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_RX_DURATION))) {
+		for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
+			sinfo->rx_duration += sta->airtime[ac].rx_airtime;
+		sinfo->filled |= BIT(NL80211_STA_INFO_RX_DURATION);
+	}
+
+	if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_TX_DURATION))) {
+		for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
+			sinfo->tx_duration += sta->airtime[ac].tx_airtime;
+		sinfo->filled |= BIT(NL80211_STA_INFO_TX_DURATION);
+	}
+
+	if (!(sinfo->filled & BIT_ULL(NL80211_STA_INFO_AIRTIME_WEIGHT))) {
+		sinfo->airtime_weight = sta->airtime_weight;
+		sinfo->filled |= BIT(NL80211_STA_INFO_AIRTIME_WEIGHT);
+	}
+
 	sinfo->rx_dropped_misc = sta->rx_stats.dropped;
 	if (sta->pcpu_rx_stats) {
 		for_each_possible_cpu(cpu) {
diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h
index 9a04327d71d1..b1b0fd6a2e21 100644
--- a/net/mac80211/sta_info.h
+++ b/net/mac80211/sta_info.h
@@ -127,6 +127,16 @@  enum ieee80211_agg_stop_reason {
 	AGG_STOP_DESTROY_STA,
 };
 
+/* Debugfs flags to enable/disable use of RX/TX airtime in scheduler */
+#define AIRTIME_USE_TX		BIT(0)
+#define AIRTIME_USE_RX		BIT(1)
+
+struct airtime_info {
+	u64 rx_airtime;
+	u64 tx_airtime;
+	s64 deficit;
+};
+
 struct sta_info;
 
 /**
@@ -563,6 +573,9 @@  struct sta_info {
 	} tx_stats;
 	u16 tid_seq[IEEE80211_QOS_CTL_TID_MASK + 1];
 
+	struct airtime_info airtime[IEEE80211_NUM_ACS];
+	u16 airtime_weight;
+
 	/*
 	 * Aggregation information, locked with lock.
 	 */
diff --git a/net/mac80211/status.c b/net/mac80211/status.c
index 3f0b96e1e02f..5b9952b1caf3 100644
--- a/net/mac80211/status.c
+++ b/net/mac80211/status.c
@@ -823,6 +823,12 @@  static void __ieee80211_tx_status(struct ieee80211_hw *hw,
 			ieee80211_sta_tx_notify(sta->sdata, (void *) skb->data,
 						acked, info->status.tx_time);
 
+		if (info->status.tx_time &&
+		    wiphy_ext_feature_isset(local->hw.wiphy,
+					    NL80211_EXT_FEATURE_AIRTIME_FAIRNESS))
+			ieee80211_sta_register_airtime(&sta->sta, tid,
+						       info->status.tx_time, 0);
+
 		if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS)) {
 			if (info->flags & IEEE80211_TX_STAT_ACK) {
 				if (sta->status_stats.lost_packets)
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index ae897c4d2520..41fbb6291eb0 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1488,8 +1488,11 @@  void ieee80211_txq_purge(struct ieee80211_local *local,
 	struct fq *fq = &local->fq;
 	struct fq_tin *tin = &txqi->tin;
 
+	spin_lock_bh(&fq->lock);
 	fq_tin_reset(fq, tin, fq_skb_free_func);
 	ieee80211_purge_tx_queue(&local->hw, &txqi->frags);
+	spin_unlock_bh(&fq->lock);
+
 	spin_lock_bh(&local->active_txq_lock[txqi->txq.ac]);
 	list_del_init(&txqi->schedule_order);
 	spin_unlock_bh(&local->active_txq_lock[txqi->txq.ac]);
@@ -3638,11 +3641,28 @@  struct ieee80211_txq *ieee80211_next_txq(struct ieee80211_hw *hw, u8 ac)
 
 	lockdep_assert_held(&local->active_txq_lock[ac]);
 
+ begin:
 	txqi = list_first_entry_or_null(&local->active_txqs[ac],
 					struct txq_info,
 					schedule_order);
+	if (!txqi)
+		return NULL;
+
+	if (txqi->txq.sta) {
+		struct sta_info *sta = container_of(txqi->txq.sta,
+						struct sta_info, sta);
+
+		if (sta->airtime[txqi->txq.ac].deficit < 0) {
+			sta->airtime[txqi->txq.ac].deficit +=
+				sta->airtime_weight;
+			list_move_tail(&txqi->schedule_order,
+				       &local->active_txqs[txqi->txq.ac]);
+			goto begin;
+		}
+	}
+
 
-	if (!txqi || txqi->schedule_round == local->schedule_round[ac])
+	if (txqi->schedule_round == local->schedule_round[ac])
 		return NULL;
 
 	list_del_init(&txqi->schedule_order);
@@ -3660,12 +3680,74 @@  void ieee80211_return_txq(struct ieee80211_hw *hw,
 	lockdep_assert_held(&local->active_txq_lock[txq->ac]);
 
 	if (list_empty(&txqi->schedule_order) &&
-	    (!skb_queue_empty(&txqi->frags) || txqi->tin.backlog_packets))
-		list_add_tail(&txqi->schedule_order,
-			      &local->active_txqs[txq->ac]);
+	    (!skb_queue_empty(&txqi->frags) || txqi->tin.backlog_packets)) {
+		/* If airtime accounting is active, always enqueue STAs at the
+		 * head of the list to ensure that they only get moved to the
+		 * back by the airtime DRR scheduler once they have a negative
+		 * deficit. A station that already has a negative deficit will
+		 * get immediately moved to the back of the list on the next
+		 * call to ieee80211_next_txq().
+		 */
+		if (txqi->txq.sta &&
+		    wiphy_ext_feature_isset(local->hw.wiphy,
+					    NL80211_EXT_FEATURE_AIRTIME_FAIRNESS))
+			list_add(&txqi->schedule_order,
+				 &local->active_txqs[txq->ac]);
+		else
+			list_add_tail(&txqi->schedule_order,
+				      &local->active_txqs[txq->ac]);
+	}
 }
 EXPORT_SYMBOL(ieee80211_return_txq);
 
+bool ieee80211_txq_may_transmit(struct ieee80211_hw *hw,
+				struct ieee80211_txq *txq)
+{
+	struct ieee80211_local *local = hw_to_local(hw);
+	struct txq_info *iter, *tmp, *txqi = to_txq_info(txq);
+	struct sta_info *sta;
+	u8 ac = txq->ac;
+
+	lockdep_assert_held(&local->active_txq_lock[ac]);
+
+	if (!txqi->txq.sta)
+		goto out;
+
+	if (list_empty(&txqi->schedule_order))
+		goto out;
+
+	list_for_each_entry_safe(iter, tmp, &local->active_txqs[ac],
+				 schedule_order) {
+		if (iter == txqi)
+			break;
+
+		if (!iter->txq.sta) {
+			list_move_tail(&iter->schedule_order,
+				       &local->active_txqs[ac]);
+			continue;
+		}
+		sta = container_of(iter->txq.sta, struct sta_info, sta);
+		if (sta->airtime[ac].deficit < 0)
+			sta->airtime[ac].deficit += sta->airtime_weight;
+		list_move_tail(&iter->schedule_order, &local->active_txqs[ac]);
+	}
+
+	sta = container_of(txqi->txq.sta, struct sta_info, sta);
+	if (sta->airtime[ac].deficit >= 0)
+		goto out;
+
+	sta->airtime[ac].deficit += sta->airtime_weight;
+	list_move_tail(&txqi->schedule_order, &local->active_txqs[ac]);
+
+	return false;
+out:
+	if (!list_empty(&txqi->schedule_order))
+		list_del_init(&txqi->schedule_order);
+
+	return true;
+}
+EXPORT_SYMBOL(ieee80211_txq_may_transmit);
+
 void ieee80211_txq_schedule_start(struct ieee80211_hw *hw, u8 ac)
 {
 	struct ieee80211_local *local = hw_to_local(hw);