Return-path: Received: from nbd.name ([46.4.11.11]:36138 "EHLO nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753180Ab0LPX5U (ORCPT ); Thu, 16 Dec 2010 18:57:20 -0500 From: Felix Fietkau To: linux-wireless@vger.kernel.org Cc: linville@tuxdriver.com, lrodriguez@atheros.com, Felix Fietkau Subject: [PATCH 1/2] ath9k: fix queue depth check for forming new aggregates Date: Fri, 17 Dec 2010 00:57:00 +0100 Message-Id: <1292543821-95686-1-git-send-email-nbd@openwrt.org> Sender: linux-wireless-owner@vger.kernel.org List-ID: To improve aggregation length, there should not be more than two fully formed A-MPDU frames in the hardware queue. To ensure this, the code checks the tx queue length before forming new A-MPDUs. This can reduce the throughput (or maybe even starve out A-MPDU traffic) when too many non-aggregated frames are in the queue. Fix this by keeping track of pending A-MPDU frames (even when they're sent out as single frames), but exclude rate control probing frames to improve performance. Signed-off-by: Felix Fietkau --- drivers/net/wireless/ath/ath9k/ath9k.h | 1 + drivers/net/wireless/ath/ath9k/xmit.c | 21 ++++++++++++++++++--- 2 files changed, 19 insertions(+), 3 deletions(-) diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h index b0b1216..9fd9519 100644 --- a/drivers/net/wireless/ath/ath9k/ath9k.h +++ b/drivers/net/wireless/ath/ath9k/ath9k.h @@ -189,6 +189,7 @@ struct ath_txq { struct list_head axq_q; spinlock_t axq_lock; u32 axq_depth; + u32 axq_ampdu_depth; bool stopped; bool axq_tx_inprogress; struct list_head axq_acq; diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c index 96623695..332d1fe 100644 --- a/drivers/net/wireless/ath/ath9k/xmit.c +++ b/drivers/net/wireless/ath/ath9k/xmit.c @@ -838,7 +838,7 @@ static void ath_tx_sched_aggr(struct ath_softc *sc, struct ath_txq *txq, ath_tx_txqaddbuf(sc, txq, &bf_q); TX_STAT_INC(txq->axq_qnum, a_aggr); - } while (txq->axq_depth < ATH_AGGR_MIN_QDEPTH && + } while (txq->axq_ampdu_depth < ATH_AGGR_MIN_QDEPTH && status != ATH_AGGR_BAW_CLOSED); } @@ -999,6 +999,7 @@ struct ath_txq *ath_txq_setup(struct ath_softc *sc, int qtype, int subtype) INIT_LIST_HEAD(&txq->axq_acq); spin_lock_init(&txq->axq_lock); txq->axq_depth = 0; + txq->axq_ampdu_depth = 0; txq->axq_tx_inprogress = false; sc->tx.txqsetup |= 1<bf_mpdu); + return bf_isampdu(bf) && !(info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE); +} + /* * Drain a given TX queue (could be Beacon or Data) * @@ -1126,7 +1133,8 @@ void ath_draintxq(struct ath_softc *sc, struct ath_txq *txq, bool retry_tx) } txq->axq_depth--; - + if (bf_is_ampdu_not_probing(bf)) + txq->axq_ampdu_depth--; spin_unlock_bh(&txq->axq_lock); if (bf_isampdu(bf)) @@ -1316,6 +1324,8 @@ static void ath_tx_txqaddbuf(struct ath_softc *sc, struct ath_txq *txq, ath9k_hw_txstart(ah, txq->axq_qnum); } txq->axq_depth++; + if (bf_is_ampdu_not_probing(bf)) + txq->axq_ampdu_depth++; } static void ath_tx_send_ampdu(struct ath_softc *sc, struct ath_atx_tid *tid, @@ -1336,7 +1346,7 @@ static void ath_tx_send_ampdu(struct ath_softc *sc, struct ath_atx_tid *tid, */ if (!list_empty(&tid->buf_q) || tid->paused || !BAW_WITHIN(tid->seq_start, tid->baw_size, fi->seqno) || - txctl->txq->axq_depth >= ATH_AGGR_MIN_QDEPTH) { + txctl->txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH) { /* * Add this frame to software queue for scheduling later * for aggregation. @@ -2040,6 +2050,9 @@ static void ath_tx_processq(struct ath_softc *sc, struct ath_txq *txq) txq->axq_tx_inprogress = false; if (bf_held) list_del(&bf_held->list); + + if (bf_is_ampdu_not_probing(bf)) + txq->axq_ampdu_depth--; spin_unlock_bh(&txq->axq_lock); if (bf_held) @@ -2168,6 +2181,8 @@ void ath_tx_edma_tasklet(struct ath_softc *sc) INCR(txq->txq_tailidx, ATH_TXFIFO_DEPTH); txq->axq_depth--; txq->axq_tx_inprogress = false; + if (bf_is_ampdu_not_probing(bf)) + txq->axq_ampdu_depth--; spin_unlock_bh(&txq->axq_lock); txok = !(txs.ts_status & ATH9K_TXERR_MASK); -- 1.7.3.2