On 12/17/2025 11:21 PM, Behera, VIVEK wrote:
Hello colleagues,
-----Original Message-----
From: Kwapulinski, Piotr <[email protected]>
Sent: Tuesday, December 16, 2025 6:55 PM
To: Behera, Vivek (DI FA DSP ICC PRC1) <[email protected]>;
Loktionov, Aleksandr <[email protected]>; Keller, Jacob E
<[email protected]>; Nguyen, Anthony L <[email protected]>;
Kitszel, Przemyslaw <[email protected]>
Cc: [email protected]; [email protected]; Behera, Vivek (DI FA
DSP ICC PRC1) <[email protected]>
Subject: RE: [Intel-wired-lan] [PATCH iwl-net v8] igc: Fix trigger of incorrect
irq in
igc_xsk_wakeup function
-----Original Message-----
From: Intel-wired-lan <[email protected]> On Behalf Of
Vivek Behera
Sent: Monday, December 15, 2025 1:21 PM
To: Loktionov, Aleksandr <[email protected]>; Keller, Jacob
E <[email protected]>; Nguyen, Anthony L
<[email protected]>; Kitszel, Przemyslaw
<[email protected]>
Cc: [email protected]; [email protected]; Behera, Vivek
<[email protected]>
Subject: [Intel-wired-lan] [PATCH iwl-net v8] 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: fc9df2a0b520 ("igc: Enable RX via AF_XDP zero-copy")
Fixes: 15fd021bc427 ("igc: Add Tx hardware timestamp request for AF_XDP
zero-copy packet")
Signed-off-by: Vivek Behera <[email protected]>
Reviewed-by: Jacob Keller <[email protected]>
Reviewed-by: Aleksandr loktinov <[email protected]>
Reviewed-by: Przemyslaw Kitszel <[email protected]>
Reviewed-by: Tony Nguyen <[email protected]>
Unless you have received a Reviewed-by tag explicitly from the person,
you shouldn't add it.
...
drivers/net/ethernet/intel/igc/igc_main.c | 90 ++++++++++++++++++-----
drivers/net/ethernet/intel/igc/igc_ptp.c | 2 +-
2 files changed, 73 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..76e4790bd3c0 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 +6922,80 @@ 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)
+ 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. */
nit: This can just be one comment, no need to break it into two comment
blocks
/* 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 */
+ u32 eics_tx = 0;
+ u32 eics_rx = 0;
+ struct napi_struct *rx_napi;
+ struct napi_struct *tx_napi;
This should be RCT, longest argument to shortest, so the structs should
be first.
+
+ if (queue_id >= adapter->num_rx_queues)
+ return -EINVAL;
+
+ if (queue_id >= adapter->num_tx_queues)
+ return -EINVAL;
+
+ /* IRQ trigger preparation for Rx */
+ ring = adapter->rx_ring[queue_id];
+ if (!ring->xsk_pool)
+ return -ENXIO;
+ q_vector = ring->q_vector;
+ rx_napi = &q_vector->napi;
+ /* Extend the BIT mask for eics */
+ eics_rx |= ring->q_vector->eims_value;
+
+ /* IRQ trigger preparation for Tx */
+ ring = adapter->tx_ring[queue_id];
+ if (!ring->xsk_pool)
+ return -ENXIO;
+ q_vector = ring->q_vector;
+ tx_napi = &q_vector->napi;
+ /* Extend the BIT mask for eics */
+ eics_tx |= ring->q_vector->eims_value;
+
+ /* Check and update napi states for rx and tx */
+ if (!napi_if_scheduled_mark_missed(rx_napi))
+ eics |= eics_rx;
+ if (!napi_if_scheduled_mark_missed(tx_napi))
+ eics |= eics_tx;
+
+ /* Now we trigger the required irqs for Rx and Tx */
+ if (eics)
+ 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;
-
- ring = adapter->rx_ring[queue_id];
-
+ }
+ /* Prepare to trigger single irq */
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);
-
+ 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
Reviewed-by: Piotr Kwapulinski <[email protected]>
Thanks for all the reviews. Are there any suggestions before I add netdev@ and
linux-kernel@ to the list for further review
For this patch, I don't think I would re-add them. As part of normal
process (future patches), yes, but this one was asked to be excluded
while the kinks of the upstream process were worked out. As this is the
list you're targeting your patch for and I'll be sending this to netdev
following our validation, it will get its review from netdev at that time.
Also, adding Siang who is one of the authors from the Fixes:
Thanks,
Tony
Regards
Vivek
