From ea852c17f5382a0a52041cfbd9a4451ae0fa1a38 Mon Sep 17 00:00:00 2001 From: Gerhard Engleder Date: Fri, 15 Sep 2023 23:01:24 +0200 Subject: [PATCH 1/3] tsnep: Fix NAPI scheduling According to the NAPI documentation networking/napi.rst, drivers which have to mask interrupts explicitly should use the napi_schedule_prep() and __napi_schedule() calls. No problem seen so far with current implementation. Nevertheless, let's align the implementation with documentation. Signed-off-by: Gerhard Engleder Signed-off-by: David S. Miller --- drivers/net/ethernet/engleder/tsnep_main.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/engleder/tsnep_main.c b/drivers/net/ethernet/engleder/tsnep_main.c index f61bd89734c5..0cdf0de555ed 100644 --- a/drivers/net/ethernet/engleder/tsnep_main.c +++ b/drivers/net/ethernet/engleder/tsnep_main.c @@ -87,8 +87,11 @@ static irqreturn_t tsnep_irq(int irq, void *arg) /* handle TX/RX queue 0 interrupt */ if ((active & adapter->queue[0].irq_mask) != 0) { - tsnep_disable_irq(adapter, adapter->queue[0].irq_mask); - napi_schedule(&adapter->queue[0].napi); + if (napi_schedule_prep(&adapter->queue[0].napi)) { + tsnep_disable_irq(adapter, adapter->queue[0].irq_mask); + /* schedule after masking to avoid races */ + __napi_schedule(&adapter->queue[0].napi); + } } return IRQ_HANDLED; @@ -99,8 +102,11 @@ static irqreturn_t tsnep_irq_txrx(int irq, void *arg) struct tsnep_queue *queue = arg; /* handle TX/RX queue interrupt */ - tsnep_disable_irq(queue->adapter, queue->irq_mask); - napi_schedule(&queue->napi); + if (napi_schedule_prep(&queue->napi)) { + tsnep_disable_irq(queue->adapter, queue->irq_mask); + /* schedule after masking to avoid races */ + __napi_schedule(&queue->napi); + } return IRQ_HANDLED; } From a7f991953d73dd50c4c23b5437c0139960e1fad4 Mon Sep 17 00:00:00 2001 From: Gerhard Engleder Date: Fri, 15 Sep 2023 23:01:25 +0200 Subject: [PATCH 2/3] tsnep: Fix ethtool channels According to the NAPI documentation networking/napi.rst, for the ethtool API a channel is a IRQ/NAPI which services queues of a given type. tsnep uses a single IRQ/NAPI instance for every TX/RX queue pair. Therefore, combined channels shall be returned instead of separate tx/rx channels. Signed-off-by: Gerhard Engleder Signed-off-by: David S. Miller --- drivers/net/ethernet/engleder/tsnep_ethtool.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/engleder/tsnep_ethtool.c b/drivers/net/ethernet/engleder/tsnep_ethtool.c index 716815dad7d2..65ec1abc9442 100644 --- a/drivers/net/ethernet/engleder/tsnep_ethtool.c +++ b/drivers/net/ethernet/engleder/tsnep_ethtool.c @@ -300,10 +300,8 @@ static void tsnep_ethtool_get_channels(struct net_device *netdev, { struct tsnep_adapter *adapter = netdev_priv(netdev); - ch->max_rx = adapter->num_rx_queues; - ch->max_tx = adapter->num_tx_queues; - ch->rx_count = adapter->num_rx_queues; - ch->tx_count = adapter->num_tx_queues; + ch->max_combined = adapter->num_queues; + ch->combined_count = adapter->num_queues; } static int tsnep_ethtool_get_ts_info(struct net_device *netdev, From 46589db3817bd8b523701274885984b5a5dda7d1 Mon Sep 17 00:00:00 2001 From: Gerhard Engleder Date: Fri, 15 Sep 2023 23:01:26 +0200 Subject: [PATCH 3/3] tsnep: Fix NAPI polling with budget 0 According to the NAPI documentation networking/napi.rst, Rx specific APIs like page pool and XDP cannot be used at all when budget is 0. skb Tx processing should happen regardless of the budget. Stop NAPI polling after Tx processing and skip Rx processing if budget is 0. Signed-off-by: Gerhard Engleder Signed-off-by: David S. Miller --- drivers/net/ethernet/engleder/tsnep_main.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/net/ethernet/engleder/tsnep_main.c b/drivers/net/ethernet/engleder/tsnep_main.c index 0cdf0de555ed..8b992dc9bb52 100644 --- a/drivers/net/ethernet/engleder/tsnep_main.c +++ b/drivers/net/ethernet/engleder/tsnep_main.c @@ -1734,6 +1734,10 @@ static int tsnep_poll(struct napi_struct *napi, int budget) if (queue->tx) complete = tsnep_tx_poll(queue->tx, budget); + /* handle case where we are called by netpoll with a budget of 0 */ + if (unlikely(budget <= 0)) + return budget; + if (queue->rx) { done = queue->rx->xsk_pool ? tsnep_rx_poll_zc(queue->rx, napi, budget) :