Return-path: Received: from nbd.name ([46.4.11.11]:34553 "EHLO nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750901Ab1LSPqH (ORCPT ); Mon, 19 Dec 2011 10:46:07 -0500 From: Felix Fietkau To: linux-wireless@vger.kernel.org Cc: linville@tuxdriver.com, mcgrof@qca.qualcomm.com, mohammed@qca.qualcomm.com Subject: [PATCH] ath9k: fix tx locking issues Date: Mon, 19 Dec 2011 16:45:54 +0100 Message-Id: <1324309554-78839-1-git-send-email-nbd@openwrt.org> (sfid-20111219_164611_964860_B05B6425) Sender: linux-wireless-owner@vger.kernel.org List-ID: The commit "ath9k: simplify tx locking" introduced a soft lockup triggered by mac80211 sending a BAR frame triggered by a driver call to ieee80211_tx_send_bar or ieee80211_tx_status. Fix these issues by queueing processed tx status skbs and submitting them to mac80211 outside of the lock. Signed-off-by: Felix Fietkau Signed-off-by: Mohammed Shafi Shajakhan --- drivers/net/wireless/ath/ath9k/ath9k.h | 1 + drivers/net/wireless/ath/ath9k/xmit.c | 96 +++++++++++++++++++++----------- 2 files changed, 65 insertions(+), 32 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h index 130e5db..95276e9 100644 --- a/drivers/net/wireless/ath/ath9k/ath9k.h +++ b/drivers/net/wireless/ath/ath9k/ath9k.h @@ -196,6 +196,7 @@ struct ath_txq { u8 txq_headidx; u8 txq_tailidx; int pending_frames; + struct sk_buff_head complete_q; }; struct ath_atx_ac { diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c index 23e80e6..60d372b 100644 --- a/drivers/net/wireless/ath/ath9k/xmit.c +++ b/drivers/net/wireless/ath/ath9k/xmit.c @@ -104,6 +104,29 @@ static int ath_max_4ms_framelen[4][32] = { /* Aggregation logic */ /*********************/ +static void ath_txq_lock(struct ath_softc *sc, struct ath_txq *txq) +{ + spin_lock_bh(&txq->axq_lock); +} + +static void ath_txq_unlock(struct ath_softc *sc, struct ath_txq *txq) +{ + spin_unlock_bh(&txq->axq_lock); +} + +static void ath_txq_unlock_complete(struct ath_softc *sc, struct ath_txq *txq) +{ + struct sk_buff_head q; + struct sk_buff *skb; + + __skb_queue_head_init(&q); + skb_queue_splice_init(&txq->complete_q, &q); + spin_unlock_bh(&txq->axq_lock); + + while ((skb = __skb_dequeue(&q))) + ieee80211_tx_status(sc->hw, skb); +} + static void ath_tx_queue_tid(struct ath_txq *txq, struct ath_atx_tid *tid) { struct ath_atx_ac *ac = tid->ac; @@ -130,7 +153,7 @@ static void ath_tx_resume_tid(struct ath_softc *sc, struct ath_atx_tid *tid) WARN_ON(!tid->paused); - spin_lock_bh(&txq->axq_lock); + ath_txq_lock(sc, txq); tid->paused = false; if (skb_queue_empty(&tid->buf_q)) @@ -139,7 +162,7 @@ static void ath_tx_resume_tid(struct ath_softc *sc, struct ath_atx_tid *tid) ath_tx_queue_tid(txq, tid); ath_txq_schedule(sc, txq); unlock: - spin_unlock_bh(&txq->axq_lock); + ath_txq_unlock_complete(sc, txq); } static struct ath_frame_info *get_frame_info(struct sk_buff *skb) @@ -189,8 +212,11 @@ static void ath_tx_flush_tid(struct ath_softc *sc, struct ath_atx_tid *tid) tid->state &= ~AGGR_CLEANUP; } - if (sendbar) + if (sendbar) { + ath_txq_unlock(sc, txq); ath_send_bar(tid, tid->seq_start); + ath_txq_lock(sc, txq); + } } static void ath_tx_update_baw(struct ath_softc *sc, struct ath_atx_tid *tid, @@ -554,13 +580,6 @@ static void ath_tx_complete_aggr(struct ath_softc *sc, struct ath_txq *txq, bf = bf_next; } - if (bar_index >= 0) { - u16 bar_seq = ATH_BA_INDEX2SEQ(seq_first, bar_index); - ath_send_bar(tid, ATH_BA_INDEX2SEQ(seq_first, bar_index + 1)); - if (BAW_WITHIN(tid->seq_start, tid->baw_size, bar_seq)) - tid->bar_index = ATH_BA_INDEX(tid->seq_start, bar_seq); - } - /* prepend un-acked frames to the beginning of the pending frame queue */ if (!skb_queue_empty(&bf_pending)) { if (an->sleeping) @@ -575,6 +594,17 @@ static void ath_tx_complete_aggr(struct ath_softc *sc, struct ath_txq *txq, } } + if (bar_index >= 0) { + u16 bar_seq = ATH_BA_INDEX2SEQ(seq_first, bar_index); + + if (BAW_WITHIN(tid->seq_start, tid->baw_size, bar_seq)) + tid->bar_index = ATH_BA_INDEX(tid->seq_start, bar_seq); + + ath_txq_unlock(sc, txq); + ath_send_bar(tid, ATH_BA_INDEX2SEQ(seq_first, bar_index + 1)); + ath_txq_lock(sc, txq); + } + if (tid->state & AGGR_CLEANUP) ath_tx_flush_tid(sc, tid); @@ -1172,7 +1202,7 @@ void ath_tx_aggr_stop(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid) return; } - spin_lock_bh(&txq->axq_lock); + ath_txq_lock(sc, txq); txtid->paused = true; /* @@ -1187,7 +1217,7 @@ void ath_tx_aggr_stop(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid) txtid->state &= ~AGGR_ADDBA_COMPLETE; ath_tx_flush_tid(sc, txtid); - spin_unlock_bh(&txq->axq_lock); + ath_txq_unlock_complete(sc, txq); } void ath_tx_aggr_sleep(struct ieee80211_sta *sta, struct ath_softc *sc, @@ -1208,7 +1238,7 @@ void ath_tx_aggr_sleep(struct ieee80211_sta *sta, struct ath_softc *sc, ac = tid->ac; txq = ac->txq; - spin_lock_bh(&txq->axq_lock); + ath_txq_lock(sc, txq); buffered = !skb_queue_empty(&tid->buf_q); @@ -1220,7 +1250,7 @@ void ath_tx_aggr_sleep(struct ieee80211_sta *sta, struct ath_softc *sc, list_del(&ac->list); } - spin_unlock_bh(&txq->axq_lock); + ath_txq_unlock(sc, txq); ieee80211_sta_set_buffered(sta, tidno, buffered); } @@ -1239,7 +1269,7 @@ void ath_tx_aggr_wakeup(struct ath_softc *sc, struct ath_node *an) ac = tid->ac; txq = ac->txq; - spin_lock_bh(&txq->axq_lock); + ath_txq_lock(sc, txq); ac->clear_ps_filter = true; if (!skb_queue_empty(&tid->buf_q) && !tid->paused) { @@ -1247,7 +1277,7 @@ void ath_tx_aggr_wakeup(struct ath_softc *sc, struct ath_node *an) ath_txq_schedule(sc, txq); } - spin_unlock_bh(&txq->axq_lock); + ath_txq_unlock_complete(sc, txq); } } @@ -1347,6 +1377,7 @@ struct ath_txq *ath_txq_setup(struct ath_softc *sc, int qtype, int subtype) txq->axq_qnum = axq_qnum; txq->mac80211_qnum = -1; txq->axq_link = NULL; + __skb_queue_head_init(&txq->complete_q); INIT_LIST_HEAD(&txq->axq_q); INIT_LIST_HEAD(&txq->axq_acq); spin_lock_init(&txq->axq_lock); @@ -1471,7 +1502,8 @@ static void ath_drain_txq_list(struct ath_softc *sc, struct ath_txq *txq, */ void ath_draintxq(struct ath_softc *sc, struct ath_txq *txq, bool retry_tx) { - spin_lock_bh(&txq->axq_lock); + ath_txq_lock(sc, txq); + if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) { int idx = txq->txq_tailidx; @@ -1492,7 +1524,7 @@ void ath_draintxq(struct ath_softc *sc, struct ath_txq *txq, bool retry_tx) if ((sc->sc_flags & SC_OP_TXAGGR) && !retry_tx) ath_txq_drain_pending_buffers(sc, txq); - spin_unlock_bh(&txq->axq_lock); + ath_txq_unlock_complete(sc, txq); } bool ath_drain_all_txq(struct ath_softc *sc, bool retry_tx) @@ -1925,7 +1957,8 @@ int ath_tx_start(struct ieee80211_hw *hw, struct sk_buff *skb, */ q = skb_get_queue_mapping(skb); - spin_lock_bh(&txq->axq_lock); + + ath_txq_lock(sc, txq); if (txq == sc->tx.txq_map[q] && ++txq->pending_frames > ATH_MAX_QDEPTH && !txq->stopped) { ieee80211_stop_queue(sc->hw, q); @@ -1934,7 +1967,7 @@ int ath_tx_start(struct ieee80211_hw *hw, struct sk_buff *skb, ath_tx_start_dma(sc, skb, txctl); - spin_unlock_bh(&txq->axq_lock); + ath_txq_unlock(sc, txq); return 0; } @@ -1946,7 +1979,6 @@ int ath_tx_start(struct ieee80211_hw *hw, struct sk_buff *skb, static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb, int tx_flags, struct ath_txq *txq) { - struct ieee80211_hw *hw = sc->hw; struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb); struct ath_common *common = ath9k_hw_common(sc->sc_ah); struct ieee80211_hdr * hdr = (struct ieee80211_hdr *)skb->data; @@ -1990,7 +2022,7 @@ static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb, } } - ieee80211_tx_status(hw, skb); + __skb_queue_tail(&txq->complete_q, skb); } static void ath_tx_complete_buf(struct ath_softc *sc, struct ath_buf *bf, @@ -2126,7 +2158,7 @@ static void ath_tx_processq(struct ath_softc *sc, struct ath_txq *txq) txq->axq_qnum, ath9k_hw_gettxbuf(sc->sc_ah, txq->axq_qnum), txq->axq_link); - spin_lock_bh(&txq->axq_lock); + ath_txq_lock(sc, txq); for (;;) { if (work_pending(&sc->hw_reset_work)) break; @@ -2185,7 +2217,7 @@ static void ath_tx_processq(struct ath_softc *sc, struct ath_txq *txq) ath_tx_process_buffer(sc, txq, &ts, bf, &bf_head); } - spin_unlock_bh(&txq->axq_lock); + ath_txq_unlock_complete(sc, txq); } static void ath_tx_complete_poll_work(struct work_struct *work) @@ -2202,17 +2234,17 @@ static void ath_tx_complete_poll_work(struct work_struct *work) for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) if (ATH_TXQ_SETUP(sc, i)) { txq = &sc->tx.txq[i]; - spin_lock_bh(&txq->axq_lock); + ath_txq_lock(sc, txq); if (txq->axq_depth) { if (txq->axq_tx_inprogress) { needreset = true; - spin_unlock_bh(&txq->axq_lock); + ath_txq_unlock(sc, txq); break; } else { txq->axq_tx_inprogress = true; } } - spin_unlock_bh(&txq->axq_lock); + ath_txq_unlock_complete(sc, txq); } if (needreset) { @@ -2270,10 +2302,10 @@ void ath_tx_edma_tasklet(struct ath_softc *sc) txq = &sc->tx.txq[ts.qid]; - spin_lock_bh(&txq->axq_lock); + ath_txq_lock(sc, txq); if (list_empty(&txq->txq_fifo[txq->txq_tailidx])) { - spin_unlock_bh(&txq->axq_lock); + ath_txq_unlock(sc, txq); return; } @@ -2299,7 +2331,7 @@ void ath_tx_edma_tasklet(struct ath_softc *sc) } ath_tx_process_buffer(sc, txq, &ts, bf, &bf_head); - spin_unlock_bh(&txq->axq_lock); + ath_txq_unlock_complete(sc, txq); } } @@ -2437,7 +2469,7 @@ void ath_tx_node_cleanup(struct ath_softc *sc, struct ath_node *an) ac = tid->ac; txq = ac->txq; - spin_lock_bh(&txq->axq_lock); + ath_txq_lock(sc, txq); if (tid->sched) { list_del(&tid->list); @@ -2453,6 +2485,6 @@ void ath_tx_node_cleanup(struct ath_softc *sc, struct ath_node *an) tid->state &= ~AGGR_ADDBA_COMPLETE; tid->state &= ~AGGR_CLEANUP; - spin_unlock_bh(&txq->axq_lock); + ath_txq_unlock(sc, txq); } } -- 1.7.3.2