AW: [PATCH v4 iwl-net] igc: Fix trigger of incorrect irq in igc_xsk_wakeup function
From: Behera, VIVEK <hidden>
Date: 2025-12-10 07:09:53
Also in:
intel-wired-lan, lkml
Subsystem:
intel ethernet drivers, networking drivers, the rest · Maintainers:
Tony Nguyen, Przemek Kitszel, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Changes in v4
- Added 'Reviewed-by:' tag from: Aleksandr loktionov .
From 2cb8e6a8d3c7bf1be51e803dabf91e2b80b3a4e2 Mon Sep 17 00:00:00 2001
From: Vivek Behera <redacted>
Date: Fri, 5 Dec 2025 10:26:05 +0100
Subject: [PATCH v4 iwl-net] igc: Fix trigger of incorrect irq in
igc_xsk_wakeup function
This patch addresses the issue where the igc_xsk_wakeup function
was triggering an incorrect IRQ for tx-0 when the i226 is configured
with only 2 combined queues or in an environment with 2 active CPU cores.
This prevented XDP Zero-copy send functionality in such split IRQ
configurations.
The fix implements the correct logic for extracting q_vectors saved
during rx and tx ring allocation and utilizes flags provided by the
ndo_xsk_wakeup API to trigger the appropriate IRQ.
Fixes: fc9df2a0b520d7d439ecf464794d53e91be74b93 ("igc: Enable RX via AF_XDP zero-copy")
Fixes: 15fd021bc4270273d8f4b7f58fdda8a16214a377 ("igc: Add Tx hardware timestamp request for AF_XDP zero-copy packet")
Signed-off-by: Vivek Behera <redacted>
Reviewed-by: Jacob Keller <redacted>
Reviewed-by: Aleksandr loktionov <redacted>
---
drivers/net/ethernet/intel/igc/igc_main.c | 81 ++++++++++++++++++-----
drivers/net/ethernet/intel/igc/igc_ptp.c | 2 +-
2 files changed, 64 insertions(+), 19 deletions(-)
diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c
index 7aafa60ba0c8..a130cdf4b45b 100644
--- a/drivers/net/ethernet/intel/igc/igc_main.c
+++ b/drivers/net/ethernet/intel/igc/igc_main.c@@ -6908,21 +6908,13 @@ static int igc_xdp_xmit(struct net_device *dev, int num_frames, return nxmit; } -static void igc_trigger_rxtxq_interrupt(struct igc_adapter *adapter, - struct igc_q_vector *q_vector) -{ - struct igc_hw *hw = &adapter->hw; - u32 eics = 0; - - eics |= q_vector->eims_value; - wr32(IGC_EICS, eics); -} - int igc_xsk_wakeup(struct net_device *dev, u32 queue_id, u32 flags) { struct igc_adapter *adapter = netdev_priv(dev); + struct igc_hw *hw = &adapter->hw; struct igc_q_vector *q_vector; struct igc_ring *ring; + u32 eics = 0; if (test_bit(__IGC_DOWN, &adapter->state)) return -ENETDOWN;
@@ -6930,18 +6922,71 @@ int igc_xsk_wakeup(struct net_device *dev, u32 queue_id, u32 flags) if (!igc_xdp_is_enabled(adapter)) return -ENXIO; - if (queue_id >= adapter->num_rx_queues) - return -EINVAL; + if ((flags & XDP_WAKEUP_RX) && (flags & XDP_WAKEUP_TX)) { + /* If both TX and RX need to be woken up, */ + /* check if queue pairs are active. */ + if ((adapter->flags & IGC_FLAG_QUEUE_PAIRS)) { + /* Just get the ring params from Rx */ + if (queue_id >= adapter->num_rx_queues) + return -EINVAL; + ring = adapter->rx_ring[queue_id]; + } else { + /***Two irqs for Rx AND Tx need to be triggered***/ + if (queue_id >= adapter->num_rx_queues) + return -EINVAL; /**queue_id invalid**/ - ring = adapter->rx_ring[queue_id]; + if (queue_id >= adapter->num_tx_queues) + return -EINVAL; /**queue_id invalid**/ - if (!ring->xsk_pool) - return -ENXIO; + /**IRQ trigger preparation for Rx**/ + ring = adapter->rx_ring[queue_id]; + if (!ring->xsk_pool) + return -ENXIO; - q_vector = adapter->q_vector[queue_id]; - if (!napi_if_scheduled_mark_missed(&q_vector->napi)) - igc_trigger_rxtxq_interrupt(adapter, q_vector); + /* Retrieve the q_vector saved in the ring */ + q_vector = ring->q_vector; + if (!napi_if_scheduled_mark_missed(&q_vector->napi)) + eics |= q_vector->eims_value; + /**IRQ trigger preparation for Tx */ + ring = adapter->tx_ring[queue_id]; + if (!ring->xsk_pool) + return -ENXIO; + + /* Retrieve the q_vector saved in the ring */ + q_vector = ring->q_vector; + if (!napi_if_scheduled_mark_missed(&q_vector->napi)) + eics |= q_vector->eims_value; /**Extend the BIT mask for eics**/ + + /***Now we trigger the split irqs for Rx and Tx over eics***/ + if (eics != 0) + wr32(IGC_EICS, eics); + + return 0; + } + } else if (flags & XDP_WAKEUP_TX) { + if (queue_id >= adapter->num_tx_queues) + return -EINVAL; + /* Get the ring params from Tx */ + ring = adapter->tx_ring[queue_id]; + } else if (flags & XDP_WAKEUP_RX) { + if (queue_id >= adapter->num_rx_queues) + return -EINVAL; + /* Get the ring params from Rx */ + ring = adapter->rx_ring[queue_id]; + } else { + /* Invalid Flags */ + return -EINVAL; + } + /** Prepare to trigger single irq */ + if (!ring->xsk_pool) + return -ENXIO; + /* Retrieve the q_vector saved in the ring */ + q_vector = ring->q_vector; + if (!napi_if_scheduled_mark_missed(&q_vector->napi)) { + eics |= q_vector->eims_value; + wr32(IGC_EICS, eics); + } return 0; }
diff --git a/drivers/net/ethernet/intel/igc/igc_ptp.c b/drivers/net/ethernet/intel/igc/igc_ptp.c
index b7b46d863bee..6d8c2d639cd7 100644
--- a/drivers/net/ethernet/intel/igc/igc_ptp.c
+++ b/drivers/net/ethernet/intel/igc/igc_ptp.c@@ -550,7 +550,7 @@ static void igc_ptp_free_tx_buffer(struct igc_adapter *adapter, tstamp->buffer_type = 0; /* Trigger txrx interrupt for transmit completion */ - igc_xsk_wakeup(adapter->netdev, tstamp->xsk_queue_index, 0); + igc_xsk_wakeup(adapter->netdev, tstamp->xsk_queue_index, XDP_WAKEUP_TX); return; }
--
2.34.1