From 4ccb45857c2c0776d0f72e39768295062c1a0de1 Mon Sep 17 00:00:00 2001 From: Jose Abreu Date: Tue, 19 Feb 2019 10:38:47 +0100 Subject: net: stmmac: Fix NAPI poll in TX path when in multi-queue Commit 8fce33317023 introduced the concept of NAPI per-channel and independent cleaning of TX path. This is currently breaking performance in some cases. The scenario happens when all packets are being received in Queue 0 but the TX is performed in Queue != 0. Fix this by using different NAPI instances per each TX and RX queue, as suggested by Florian. Changes from v2: - Only force restart transmission if there are pending packets Changes from v1: - Pass entire ring size to TX clean path (Florian) Signed-off-by: Jose Abreu Cc: Florian Fainelli Cc: Joao Pinto Cc: David S. Miller Cc: Giuseppe Cavallaro Cc: Alexandre Torgue Signed-off-by: David S. Miller --- drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 115 +++++++++++++--------- 1 file changed, 66 insertions(+), 49 deletions(-) (limited to 'drivers/net/ethernet/stmicro/stmmac/stmmac_main.c') diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c index f12dd59c85cf..e2a13ec2e30b 100644 --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c @@ -155,7 +155,10 @@ static void stmmac_disable_all_queues(struct stmmac_priv *priv) for (queue = 0; queue < maxq; queue++) { struct stmmac_channel *ch = &priv->channel[queue]; - napi_disable(&ch->napi); + if (queue < rx_queues_cnt) + napi_disable(&ch->rx_napi); + if (queue < tx_queues_cnt) + napi_disable(&ch->tx_napi); } } @@ -173,7 +176,10 @@ static void stmmac_enable_all_queues(struct stmmac_priv *priv) for (queue = 0; queue < maxq; queue++) { struct stmmac_channel *ch = &priv->channel[queue]; - napi_enable(&ch->napi); + if (queue < rx_queues_cnt) + napi_enable(&ch->rx_napi); + if (queue < tx_queues_cnt) + napi_enable(&ch->tx_napi); } } @@ -1955,6 +1961,10 @@ static int stmmac_tx_clean(struct stmmac_priv *priv, int budget, u32 queue) mod_timer(&priv->eee_ctrl_timer, STMMAC_LPI_T(eee_timer)); } + /* We still have pending packets, let's call for a new scheduling */ + if (tx_q->dirty_tx != tx_q->cur_tx) + mod_timer(&tx_q->txtimer, STMMAC_COAL_TIMER(10)); + __netif_tx_unlock_bh(netdev_get_tx_queue(priv->dev, queue)); return count; @@ -2045,23 +2055,15 @@ static int stmmac_napi_check(struct stmmac_priv *priv, u32 chan) int status = stmmac_dma_interrupt_status(priv, priv->ioaddr, &priv->xstats, chan); struct stmmac_channel *ch = &priv->channel[chan]; - bool needs_work = false; - - if ((status & handle_rx) && ch->has_rx) { - needs_work = true; - } else { - status &= ~handle_rx; - } - if ((status & handle_tx) && ch->has_tx) { - needs_work = true; - } else { - status &= ~handle_tx; + if ((status & handle_rx) && (chan < priv->plat->rx_queues_to_use)) { + stmmac_disable_dma_irq(priv, priv->ioaddr, chan); + napi_schedule_irqoff(&ch->rx_napi); } - if (needs_work && napi_schedule_prep(&ch->napi)) { + if ((status & handle_tx) && (chan < priv->plat->tx_queues_to_use)) { stmmac_disable_dma_irq(priv, priv->ioaddr, chan); - __napi_schedule(&ch->napi); + napi_schedule_irqoff(&ch->tx_napi); } return status; @@ -2257,8 +2259,14 @@ static void stmmac_tx_timer(struct timer_list *t) ch = &priv->channel[tx_q->queue_index]; - if (likely(napi_schedule_prep(&ch->napi))) - __napi_schedule(&ch->napi); + /* + * If NAPI is already running we can miss some events. Let's rearm + * the timer and try again. + */ + if (likely(napi_schedule_prep(&ch->tx_napi))) + __napi_schedule(&ch->tx_napi); + else + mod_timer(&tx_q->txtimer, STMMAC_COAL_TIMER(10)); } /** @@ -3514,7 +3522,7 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue) else skb->ip_summed = CHECKSUM_UNNECESSARY; - napi_gro_receive(&ch->napi, skb); + napi_gro_receive(&ch->rx_napi, skb); priv->dev->stats.rx_packets++; priv->dev->stats.rx_bytes += frame_len; @@ -3529,40 +3537,45 @@ static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue) return count; } -/** - * stmmac_poll - stmmac poll method (NAPI) - * @napi : pointer to the napi structure. - * @budget : maximum number of packets that the current CPU can receive from - * all interfaces. - * Description : - * To look at the incoming frames and clear the tx resources. - */ -static int stmmac_napi_poll(struct napi_struct *napi, int budget) +static int stmmac_napi_poll_rx(struct napi_struct *napi, int budget) { struct stmmac_channel *ch = - container_of(napi, struct stmmac_channel, napi); + container_of(napi, struct stmmac_channel, rx_napi); struct stmmac_priv *priv = ch->priv_data; - int work_done, rx_done = 0, tx_done = 0; u32 chan = ch->index; + int work_done; priv->xstats.napi_poll++; - if (ch->has_tx) - tx_done = stmmac_tx_clean(priv, budget, chan); - if (ch->has_rx) - rx_done = stmmac_rx(priv, budget, chan); + work_done = stmmac_rx(priv, budget, chan); + if (work_done < budget && napi_complete_done(napi, work_done)) + stmmac_enable_dma_irq(priv, priv->ioaddr, chan); + return work_done; +} - work_done = max(rx_done, tx_done); - work_done = min(work_done, budget); +static int stmmac_napi_poll_tx(struct napi_struct *napi, int budget) +{ + struct stmmac_channel *ch = + container_of(napi, struct stmmac_channel, tx_napi); + struct stmmac_priv *priv = ch->priv_data; + struct stmmac_tx_queue *tx_q; + u32 chan = ch->index; + int work_done; - if (work_done < budget && napi_complete_done(napi, work_done)) { - int stat; + priv->xstats.napi_poll++; + + work_done = stmmac_tx_clean(priv, DMA_TX_SIZE, chan); + work_done = min(work_done, budget); + if (work_done < budget && napi_complete_done(napi, work_done)) stmmac_enable_dma_irq(priv, priv->ioaddr, chan); - stat = stmmac_dma_interrupt_status(priv, priv->ioaddr, - &priv->xstats, chan); - if (stat && napi_reschedule(napi)) - stmmac_disable_dma_irq(priv, priv->ioaddr, chan); + + /* Force transmission restart */ + tx_q = &priv->tx_queue[chan]; + if (tx_q->cur_tx != tx_q->dirty_tx) { + stmmac_enable_dma_transmission(priv, priv->ioaddr); + stmmac_set_tx_tail_ptr(priv, priv->ioaddr, tx_q->tx_tail_addr, + chan); } return work_done; @@ -4342,13 +4355,14 @@ int stmmac_dvr_probe(struct device *device, ch->priv_data = priv; ch->index = queue; - if (queue < priv->plat->rx_queues_to_use) - ch->has_rx = true; - if (queue < priv->plat->tx_queues_to_use) - ch->has_tx = true; - - netif_napi_add(ndev, &ch->napi, stmmac_napi_poll, - NAPI_POLL_WEIGHT); + if (queue < priv->plat->rx_queues_to_use) { + netif_napi_add(ndev, &ch->rx_napi, stmmac_napi_poll_rx, + NAPI_POLL_WEIGHT); + } + if (queue < priv->plat->tx_queues_to_use) { + netif_napi_add(ndev, &ch->tx_napi, stmmac_napi_poll_tx, + NAPI_POLL_WEIGHT); + } } mutex_init(&priv->lock); @@ -4404,7 +4418,10 @@ error_mdio_register: for (queue = 0; queue < maxq; queue++) { struct stmmac_channel *ch = &priv->channel[queue]; - netif_napi_del(&ch->napi); + if (queue < priv->plat->rx_queues_to_use) + netif_napi_del(&ch->rx_napi); + if (queue < priv->plat->tx_queues_to_use) + netif_napi_del(&ch->tx_napi); } error_hw_init: destroy_workqueue(priv->wq); -- cgit v1.2.3-55-g7522