diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 785f6363a6fc..6ce62e553dc2 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -184,10 +184,6 @@ struct ieee80211_rx_data { u16 tkip_iv16; }; -struct ieee80211_tx_stored_packet { - struct sk_buff *skb; -}; - struct beacon_data { u8 *head, *tail; int head_len, tail_len; @@ -583,6 +579,7 @@ enum queue_stop_reason { IEEE80211_QUEUE_STOP_REASON_CSA, IEEE80211_QUEUE_STOP_REASON_AGGREGATION, IEEE80211_QUEUE_STOP_REASON_SUSPEND, + IEEE80211_QUEUE_STOP_REASON_PENDING, }; struct ieee80211_master_priv { @@ -639,9 +636,7 @@ struct ieee80211_local { struct sta_info *sta_hash[STA_HASH_SIZE]; struct timer_list sta_cleanup; - unsigned long queues_pending[BITS_TO_LONGS(IEEE80211_MAX_QUEUES)]; - unsigned long queues_pending_run[BITS_TO_LONGS(IEEE80211_MAX_QUEUES)]; - struct ieee80211_tx_stored_packet pending_packet[IEEE80211_MAX_QUEUES]; + struct sk_buff_head pending[IEEE80211_MAX_QUEUES]; struct tasklet_struct tx_pending_tasklet; /* number of interfaces with corresponding IFF_ flags */ diff --git a/net/mac80211/main.c b/net/mac80211/main.c index dac68d476bff..a7430e98c531 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -781,6 +781,8 @@ struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len, sta_info_init(local); + for (i = 0; i < IEEE80211_MAX_QUEUES; i++) + skb_queue_head_init(&local->pending[i]); tasklet_init(&local->tx_pending_tasklet, ieee80211_tx_pending, (unsigned long)local); tasklet_disable(&local->tx_pending_tasklet); diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c index 0d97cad84b1b..ee1b77f8a804 100644 --- a/net/mac80211/tx.c +++ b/net/mac80211/tx.c @@ -1189,12 +1189,14 @@ static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb) struct ieee80211_tx_data tx; ieee80211_tx_result res_prepare; struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); - int ret; + struct sk_buff *next; + unsigned long flags; + int ret, retries; u16 queue; queue = skb_get_queue_mapping(skb); - WARN_ON(test_bit(queue, local->queues_pending)); + WARN_ON(!skb_queue_empty(&local->pending[queue])); if (unlikely(skb->len < 10)) { dev_kfree_skb(skb); @@ -1219,40 +1221,52 @@ static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb) if (invoke_tx_handlers(&tx)) goto out; -retry: + retries = 0; + retry: ret = __ieee80211_tx(local, &tx); - if (ret) { - struct ieee80211_tx_stored_packet *store; - + switch (ret) { + case IEEE80211_TX_OK: + break; + case IEEE80211_TX_AGAIN: /* * Since there are no fragmented frames on A-MPDU * queues, there's no reason for a driver to reject * a frame there, warn and drop it. */ - if (ret != IEEE80211_TX_PENDING) - if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU)) + if (WARN_ON(info->flags & IEEE80211_TX_CTL_AMPDU)) + goto drop; + /* fall through */ + case IEEE80211_TX_PENDING: + skb = tx.skb; + + spin_lock_irqsave(&local->queue_stop_reason_lock, flags); + + if (__netif_subqueue_stopped(local->mdev, queue)) { + do { + next = skb->next; + skb->next = NULL; + skb_queue_tail(&local->pending[queue], skb); + } while ((skb = next)); + + /* + * Make sure nobody will enable the queue on us + * (without going through the tasklet) nor disable the + * netdev queue underneath the pending handling code. + */ + __set_bit(IEEE80211_QUEUE_STOP_REASON_PENDING, + &local->queue_stop_reasons[queue]); + + spin_unlock_irqrestore(&local->queue_stop_reason_lock, + flags); + } else { + spin_unlock_irqrestore(&local->queue_stop_reason_lock, + flags); + + retries++; + if (WARN(retries > 10, "tx refused but queue active")) goto drop; - - store = &local->pending_packet[queue]; - - set_bit(queue, local->queues_pending); - smp_mb(); - /* - * When the driver gets out of buffers during sending of - * fragments and calls ieee80211_stop_queue, the netif - * subqueue is stopped. There is, however, a small window - * in which the PENDING bit is not yet set. If a buffer - * gets available in that window (i.e. driver calls - * ieee80211_wake_queue), we would end up with ieee80211_tx - * called with the PENDING bit still set. Prevent this by - * continuing transmitting here when that situation is - * possible to have happened. - */ - if (!__netif_subqueue_stopped(local->mdev, queue)) { - clear_bit(queue, local->queues_pending); goto retry; } - store->skb = tx.skb; } out: rcu_read_unlock(); @@ -1263,8 +1277,6 @@ retry: skb = tx.skb; while (skb) { - struct sk_buff *next; - next = skb->next; dev_kfree_skb(skb); skb = next; @@ -1803,23 +1815,10 @@ int ieee80211_subif_start_xmit(struct sk_buff *skb, */ void ieee80211_clear_tx_pending(struct ieee80211_local *local) { - struct sk_buff *skb; int i; - for (i = 0; i < local->hw.queues; i++) { - if (!test_bit(i, local->queues_pending)) - continue; - - skb = local->pending_packet[i].skb; - while (skb) { - struct sk_buff *next; - - next = skb->next; - dev_kfree_skb(skb); - skb = next; - } - clear_bit(i, local->queues_pending); - } + for (i = 0; i < local->hw.queues; i++) + skb_queue_purge(&local->pending[i]); } /* @@ -1830,40 +1829,57 @@ void ieee80211_tx_pending(unsigned long data) { struct ieee80211_local *local = (struct ieee80211_local *)data; struct net_device *dev = local->mdev; - struct ieee80211_tx_stored_packet *store; struct ieee80211_hdr *hdr; + unsigned long flags; struct ieee80211_tx_data tx; int i, ret; + bool next; rcu_read_lock(); netif_tx_lock_bh(dev); + for (i = 0; i < local->hw.queues; i++) { - /* Check that this queue is ok */ - if (__netif_subqueue_stopped(local->mdev, i) && - !test_bit(i, local->queues_pending_run)) + /* + * If queue is stopped by something other than due to pending + * frames, or we have no pending frames, proceed to next queue. + */ + spin_lock_irqsave(&local->queue_stop_reason_lock, flags); + next = false; + if (local->queue_stop_reasons[i] != + BIT(IEEE80211_QUEUE_STOP_REASON_PENDING) || + skb_queue_empty(&local->pending[i])) + next = true; + spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags); + + if (next) continue; - if (!test_bit(i, local->queues_pending)) { - clear_bit(i, local->queues_pending_run); - ieee80211_wake_queue(&local->hw, i); - continue; - } - - clear_bit(i, local->queues_pending_run); + /* + * start the queue now to allow processing our packets, + * we're under the tx lock here anyway so nothing will + * happen as a result of this + */ netif_start_subqueue(local->mdev, i); - store = &local->pending_packet[i]; - tx.flags = 0; - tx.skb = store->skb; - hdr = (struct ieee80211_hdr *)tx.skb->data; - tx.sta = sta_info_get(local, hdr->addr1); - ret = __ieee80211_tx(local, &tx); - store->skb = tx.skb; - if (!ret) { - clear_bit(i, local->queues_pending); - ieee80211_wake_queue(&local->hw, i); + while (!skb_queue_empty(&local->pending[i])) { + tx.flags = 0; + tx.skb = skb_dequeue(&local->pending[i]); + hdr = (struct ieee80211_hdr *)tx.skb->data; + tx.sta = sta_info_get(local, hdr->addr1); + + ret = __ieee80211_tx(local, &tx); + if (ret != IEEE80211_TX_OK) { + skb_queue_head(&local->pending[i], tx.skb); + break; + } } + + /* Start regular packet processing again. */ + if (skb_queue_empty(&local->pending[i])) + ieee80211_wake_queue_by_reason(&local->hw, i, + IEEE80211_QUEUE_STOP_REASON_PENDING); } + netif_tx_unlock_bh(dev); rcu_read_unlock(); } diff --git a/net/mac80211/util.c b/net/mac80211/util.c index 021166c8cce2..0247d8022f5f 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -365,16 +365,16 @@ static void __ieee80211_wake_queue(struct ieee80211_hw *hw, int queue, __clear_bit(reason, &local->queue_stop_reasons[queue]); + if (!skb_queue_empty(&local->pending[queue]) && + local->queue_stop_reasons[queue] == + BIT(IEEE80211_QUEUE_STOP_REASON_PENDING)) + tasklet_schedule(&local->tx_pending_tasklet); + if (local->queue_stop_reasons[queue] != 0) /* someone still has this queue stopped */ return; - if (test_bit(queue, local->queues_pending)) { - set_bit(queue, local->queues_pending_run); - tasklet_schedule(&local->tx_pending_tasklet); - } else { - netif_wake_subqueue(local->mdev, queue); - } + netif_wake_subqueue(local->mdev, queue); } void ieee80211_wake_queue_by_reason(struct ieee80211_hw *hw, int queue, @@ -420,9 +420,15 @@ static void __ieee80211_stop_queue(struct ieee80211_hw *hw, int queue, reason = IEEE80211_QUEUE_STOP_REASON_AGGREGATION; } - __set_bit(reason, &local->queue_stop_reasons[queue]); + /* + * Only stop if it was previously running, this is necessary + * for correct pending packets handling because there we may + * start (but not wake) the queue and rely on that. + */ + if (!local->queue_stop_reasons[queue]) + netif_stop_subqueue(local->mdev, queue); - netif_stop_subqueue(local->mdev, queue); + __set_bit(reason, &local->queue_stop_reasons[queue]); } void ieee80211_stop_queue_by_reason(struct ieee80211_hw *hw, int queue,