History

wifi: mac80211: Proper mark iTXQs for resumption

When a running wake_tx_queue() call is aborted due to a hw queue stop the corresponding iTXQ is not always correctly marked for resumption: wake_tx_push_queue() can stops the queue run without setting @IEEE80211_TXQ_STOP_NETIF_TX. Without the @IEEE80211_TXQ_STOP_NETIF_TX flag __ieee80211_wake_txqs() will not schedule a new queue run and remaining frames in the queue get stuck till another frame is queued to it. Fix the issue for all drivers - also the ones with custom wake_tx_queue callbacks - by moving the logic into ieee80211_tx_dequeue() and drop the redundant @txqs_stopped. @IEEE80211_TXQ_STOP_NETIF_TX is also renamed to @IEEE80211_TXQ_DIRTY to better describe the flag.

Alexander Wetzel committed 3 years ago

Commit 4444bc21 parent e66b7926 files · +21 −54Browse files

Unified · Split

6 files
  1. include/net/mac80211.h +0 −4
  2. net/mac80211/debugfs_sta.c +3 −2
  3. net/mac80211/driver-ops.h +1 −1
  4. net/mac80211/ieee80211_i.h +1 −1
  5. net/mac80211/tx.c +13 −7
  6. net/mac80211/util.c +3 −39
include/net/mac80211.h+0−4
@@ -1832,8 +1832,6 @@ struct ieee80211_vif_cfg { · 1831 unmodified lines
18321832 * @drv_priv: data area for driver use, will always be aligned to
18331833 * sizeof(void \*).
18341834 * @txq: the multicast data TX queue
1835− * @txqs_stopped: per AC flag to indicate that intermediate TXQs are stopped,
1836− * protected by fq->lock.
18371835 * @offload_flags: 802.3 -> 802.11 enapsulation offload flags, see
18381836 * &enum ieee80211_offload_flags.
18391837 * @mbssid_tx_vif: Pointer to the transmitting interface if MBSSID is enabled.
@@ -1863,8 +1861,6 @@ struct ieee80211_vif { · 23 unmodified lines
18631861 bool probe_req_reg;
18641862 bool rx_mcast_action_reg;
18651863
1866− bool txqs_stopped[IEEE80211_NUM_ACS];
1867−
18681864 struct ieee80211_vif *mbssid_tx_vif;
18691865
18701866 /* must be last */
net/mac80211/debugfs_sta.c+3−2
@@ -167,7 +167,7 @@ static ssize_t sta_aqm_read(struct file *file, char __user *userbuf, · 166 unmodified lines
167167 continue;
168168 txqi = to_txq_info(sta->sta.txq[i]);
169169 p += scnprintf(p, bufsz + buf - p,
170− "%d %d %u %u %u %u %u %u %u %u %u 0x%lx(%s%s%s)\n",
170+ "%d %d %u %u %u %u %u %u %u %u %u 0x%lx(%s%s%s%s)\n",
171171 txqi->txq.tid,
172172 txqi->txq.ac,
173173 txqi->tin.backlog_bytes,
@@ -182,7 +182,8 @@ static ssize_t sta_aqm_read(struct file *file, char __user *userbuf, · 8 unmodified lines
182182 txqi->flags,
183183 test_bit(IEEE80211_TXQ_STOP, &txqi->flags) ? "STOP" : "RUN",
184184 test_bit(IEEE80211_TXQ_AMPDU, &txqi->flags) ? " AMPDU" : "",
185− test_bit(IEEE80211_TXQ_NO_AMSDU, &txqi->flags) ? " NO-AMSDU" : "");
185+ test_bit(IEEE80211_TXQ_NO_AMSDU, &txqi->flags) ? " NO-AMSDU" : "",
186+ test_bit(IEEE80211_TXQ_DIRTY, &txqi->flags) ? " DIRTY" : "");
186187 }
187188
188189 rcu_read_unlock();
net/mac80211/driver-ops.h+1−1
@@ -1199,7 +1199,7 @@ static inline void drv_wake_tx_queue(struct ieee80211_local *local, · 1198 unmodified lines
11991199
12001200 /* In reconfig don't transmit now, but mark for waking later */
12011201 if (local->in_reconfig) {
1202− set_bit(IEEE80211_TXQ_STOP_NETIF_TX, &txq->flags);
1202+ set_bit(IEEE80211_TXQ_DIRTY, &txq->flags);
12031203 return;
12041204 }
12051205
net/mac80211/ieee80211_i.h+1−1
@@ -838,7 +838,7 @@ enum txq_info_flags { · 837 unmodified lines
838838 IEEE80211_TXQ_STOP,
839839 IEEE80211_TXQ_AMPDU,
840840 IEEE80211_TXQ_NO_AMSDU,
841− IEEE80211_TXQ_STOP_NETIF_TX,
841+ IEEE80211_TXQ_DIRTY,
842842 };
843843
844844 /**
net/mac80211/tx.c+13−7
@@ -3783,6 +3783,8 @@ struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw, · 3782 unmodified lines
37833783 struct ieee80211_tx_data tx;
37843784 ieee80211_tx_result r;
37853785 struct ieee80211_vif *vif = txq->vif;
3786+ int q = vif->hw_queue[txq->ac];
3787+ bool q_stopped;
37863788
37873789 WARN_ON_ONCE(softirq_count() == 0);
37883790
@@ -3790,16 +3792,20 @@ struct sk_buff *ieee80211_tx_dequeue(struct ieee80211_hw *hw, · 1 unmodified line
37903792 return NULL;
37913793
37923794 begin:
3793− spin_lock_bh(&fq->lock);
3795+ spin_lock(&local->queue_stop_reason_lock);
3796+ q_stopped = local->queue_stop_reasons[q];
3797+ spin_unlock(&local->queue_stop_reason_lock);
37943798
3795− if (test_bit(IEEE80211_TXQ_STOP, &txqi->flags) ||
3796− test_bit(IEEE80211_TXQ_STOP_NETIF_TX, &txqi->flags))
3797− goto out;
3799+ if (unlikely(q_stopped)) {
3800+ /* mark for waking later */
3801+ set_bit(IEEE80211_TXQ_DIRTY, &txqi->flags);
3802+ return NULL;
3803+ }
37983804
3799− if (vif->txqs_stopped[txq->ac]) {
3800− set_bit(IEEE80211_TXQ_STOP_NETIF_TX, &txqi->flags);
3805+ spin_lock_bh(&fq->lock);
3806+
3807+ if (unlikely(test_bit(IEEE80211_TXQ_STOP, &txqi->flags)))
38013808 goto out;
3802− }
38033809
38043810 /* Make sure fragments stay together. */
38053811 skb = __skb_dequeue(&txqi->frags);
net/mac80211/util.c+3−39
@@ -292,22 +292,12 @@ static void wake_tx_push_queue(struct ieee80211_local *local, · 291 unmodified lines
292292 struct ieee80211_sub_if_data *sdata,
293293 struct ieee80211_txq *queue)
294294 {
295− int q = sdata->vif.hw_queue[queue->ac];
296295 struct ieee80211_tx_control control = {
297296 .sta = queue->sta,
298297 };
299298 struct sk_buff *skb;
300− unsigned long flags;
301− bool q_stopped;
302299
303300 while (1) {
304− spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
305− q_stopped = local->queue_stop_reasons[q];
306− spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
307−
308− if (q_stopped)
309− break;
310−
311301 skb = ieee80211_tx_dequeue(&local->hw, queue);
312302 if (!skb)
313303 break;
@@ -347,8 +337,6 @@ static void __ieee80211_wake_txqs(struct ieee80211_sub_if_data *sdata, int ac) · 33 unmodified lines
347337 local_bh_disable();
348338 spin_lock(&fq->lock);
349339
350− sdata->vif.txqs_stopped[ac] = false;
351−
352340 if (!test_bit(SDATA_STATE_RUNNING, &sdata->state))
353341 goto out;
354342
@@ -370,7 +358,7 @@ static void __ieee80211_wake_txqs(struct ieee80211_sub_if_data *sdata, int ac) · 15 unmodified lines
370358 if (ac != txq->ac)
371359 continue;
372360
373− if (!test_and_clear_bit(IEEE80211_TXQ_STOP_NETIF_TX,
361+ if (!test_and_clear_bit(IEEE80211_TXQ_DIRTY,
374362 &txqi->flags))
375363 continue;
376364
@@ -385,7 +373,7 @@ static void __ieee80211_wake_txqs(struct ieee80211_sub_if_data *sdata, int ac) · 8 unmodified lines
385373
386374 txqi = to_txq_info(vif->txq);
387375
388− if (!test_and_clear_bit(IEEE80211_TXQ_STOP_NETIF_TX, &txqi->flags) ||
376+ if (!test_and_clear_bit(IEEE80211_TXQ_DIRTY, &txqi->flags) ||
389377 (ps && atomic_read(&ps->num_sta_ps)) || ac != vif->txq->ac)
390378 goto out;
391379
@@ -517,8 +505,6 @@ static void __ieee80211_stop_queue(struct ieee80211_hw *hw, int queue, · 125 unmodified lines
517505 bool refcounted)
518506 {
519507 struct ieee80211_local *local = hw_to_local(hw);
520− struct ieee80211_sub_if_data *sdata;
521− int n_acs = IEEE80211_NUM_ACS;
522508
523509 trace_stop_queue(local, queue, reason);
524510
@@ -530,29 +516,7 @@ static void __ieee80211_stop_queue(struct ieee80211_hw *hw, int queue, · 5 unmodified lines
530516 else
531517 local->q_stop_reasons[queue][reason]++;
532518
533− if (__test_and_set_bit(reason, &local->queue_stop_reasons[queue]))
534− return;
535−
536− if (local->hw.queues < IEEE80211_NUM_ACS)
537− n_acs = 1;
538−
539− rcu_read_lock();
540− list_for_each_entry_rcu(sdata, &local->interfaces, list) {
541− int ac;
542−
543− if (!sdata->dev)
544− continue;
545−
546− for (ac = 0; ac < n_acs; ac++) {
547− if (sdata->vif.hw_queue[ac] == queue ||
548− sdata->vif.cab_queue == queue) {
549− spin_lock(&local->fq.lock);
550− sdata->vif.txqs_stopped[ac] = true;
551− spin_unlock(&local->fq.lock);
552− }
553− }
554− }
555− rcu_read_unlock();
519+ set_bit(reason, &local->queue_stop_reasons[queue]);
556520 }
557521
558522 void ieee80211_stop_queue_by_reason(struct ieee80211_hw *hw, int queue,