From dea36631e6f186d4b853af67a4aef2e35cfa8bb7 Mon Sep 17 00:00:00 2001 From: Hauke Mehrtens Date: Sat, 12 Sep 2020 21:36:26 +0200 Subject: [PATCH 1/4] net: lantiq: Wake TX queue again The call to netif_wake_queue() when the TX descriptors were freed was missing. When there are no TX buffers available the TX queue will be stopped, but it was not started again when they are available again, this is fixed in this patch. Fixes: fe1a56420cf2 ("net: lantiq: Add Lantiq / Intel VRX200 Ethernet driver") Signed-off-by: Hauke Mehrtens Signed-off-by: David S. Miller --- drivers/net/ethernet/lantiq_xrx200.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c index 1645e4e7ebdb..1feb9fc710e0 100644 --- a/drivers/net/ethernet/lantiq_xrx200.c +++ b/drivers/net/ethernet/lantiq_xrx200.c @@ -268,6 +268,9 @@ static int xrx200_tx_housekeeping(struct napi_struct *napi, int budget) net_dev->stats.tx_bytes += bytes; netdev_completed_queue(ch->priv->net_dev, pkts, bytes); + if (netif_queue_stopped(net_dev)) + netif_wake_queue(net_dev); + if (pkts < budget) { napi_complete(&ch->napi); ltq_dma_enable_irq(&ch->dma); From 74c7b80e222b58d3cea731d31e2a31a77fea8345 Mon Sep 17 00:00:00 2001 From: Hauke Mehrtens Date: Sat, 12 Sep 2020 21:36:27 +0200 Subject: [PATCH 2/4] net: lantiq: use netif_tx_napi_add() for TX NAPI netif_tx_napi_add() should be used for NAPI in the TX direction instead of the netif_napi_add() function. Signed-off-by: Hauke Mehrtens Signed-off-by: David S. Miller --- drivers/net/ethernet/lantiq_xrx200.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c index 1feb9fc710e0..f34e4dc8c661 100644 --- a/drivers/net/ethernet/lantiq_xrx200.c +++ b/drivers/net/ethernet/lantiq_xrx200.c @@ -502,7 +502,7 @@ static int xrx200_probe(struct platform_device *pdev) /* setup NAPI */ netif_napi_add(net_dev, &priv->chan_rx.napi, xrx200_poll_rx, 32); - netif_napi_add(net_dev, &priv->chan_tx.napi, xrx200_tx_housekeeping, 32); + netif_tx_napi_add(net_dev, &priv->chan_tx.napi, xrx200_tx_housekeeping, 32); platform_set_drvdata(pdev, priv); From c582a7fea9dad4d309437d1a7e22e6d2cb380e2e Mon Sep 17 00:00:00 2001 From: Hauke Mehrtens Date: Sat, 12 Sep 2020 21:36:28 +0200 Subject: [PATCH 3/4] net: lantiq: Use napi_complete_done() Use napi_complete_done() and activate the interrupts when this function returns true. This way the generic NAPI code can take care of activating the interrupts. Signed-off-by: Hauke Mehrtens Signed-off-by: David S. Miller --- drivers/net/ethernet/lantiq_xrx200.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c index f34e4dc8c661..abee7d61074c 100644 --- a/drivers/net/ethernet/lantiq_xrx200.c +++ b/drivers/net/ethernet/lantiq_xrx200.c @@ -230,8 +230,8 @@ static int xrx200_poll_rx(struct napi_struct *napi, int budget) } if (rx < budget) { - napi_complete(&ch->napi); - ltq_dma_enable_irq(&ch->dma); + if (napi_complete_done(&ch->napi, rx)) + ltq_dma_enable_irq(&ch->dma); } return rx; @@ -272,8 +272,8 @@ static int xrx200_tx_housekeeping(struct napi_struct *napi, int budget) netif_wake_queue(net_dev); if (pkts < budget) { - napi_complete(&ch->napi); - ltq_dma_enable_irq(&ch->dma); + if (napi_complete_done(&ch->napi, pkts)) + ltq_dma_enable_irq(&ch->dma); } return pkts; From 9423361da52356cb68642db5b2729b6b85aad330 Mon Sep 17 00:00:00 2001 From: Hauke Mehrtens Date: Sat, 12 Sep 2020 21:36:29 +0200 Subject: [PATCH 4/4] net: lantiq: Disable IRQs only if NAPI gets scheduled The napi_schedule() call will only schedule the NAPI if it is not already running. To make sure that we do not deactivate interrupts without scheduling NAPI only deactivate the interrupts in case NAPI also gets scheduled. Signed-off-by: Hauke Mehrtens Signed-off-by: David S. Miller --- drivers/net/ethernet/lantiq_xrx200.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/lantiq_xrx200.c b/drivers/net/ethernet/lantiq_xrx200.c index abee7d61074c..635ff3a5dcfb 100644 --- a/drivers/net/ethernet/lantiq_xrx200.c +++ b/drivers/net/ethernet/lantiq_xrx200.c @@ -345,10 +345,12 @@ static irqreturn_t xrx200_dma_irq(int irq, void *ptr) { struct xrx200_chan *ch = ptr; - ltq_dma_disable_irq(&ch->dma); - ltq_dma_ack_irq(&ch->dma); + if (napi_schedule_prep(&ch->napi)) { + __napi_schedule(&ch->napi); + ltq_dma_disable_irq(&ch->dma); + } - napi_schedule(&ch->napi); + ltq_dma_ack_irq(&ch->dma); return IRQ_HANDLED; }