> -----Original Message-----
> From: Intel-wired-lan <[email protected]> On Behalf
> Of Loktionov, Aleksandr
> Sent: Tuesday, December 9, 2025 9:06 AM
> To: Behera, Vivek <[email protected]>; Behera, Vivek
> <[email protected]>; Keller, Jacob E
> <[email protected]>; Nguyen, Anthony L
> <[email protected]>; Kitszel, Przemyslaw
> <[email protected]>; Andrew Lunn <[email protected]>;
> David S. Miller <[email protected]>; Eric Dumazet
> <[email protected]>; Jakub Kicinski <[email protected]>; Paolo Abeni
> <[email protected]>
> Cc: [email protected]; [email protected]; linux-
> [email protected]
> Subject: Re: [Intel-wired-lan] [PATCH v3 iwl-net] igc: Fix trigger of
> incorrect irq in igc_xsk_wakeup function
> 
> 
> 
> > -----Original Message-----
> > From: Intel-wired-lan <[email protected]> On Behalf
> > Of Behera, VIVEK
> > Sent: Tuesday, December 9, 2025 7:47 AM
> > To: Behera, Vivek <[email protected]>; Keller, Jacob E
> > <[email protected]>; Nguyen, Anthony L
> > <[email protected]>; Kitszel, Przemyslaw
> > <[email protected]>; Andrew Lunn <[email protected]>;
> > David S. Miller <[email protected]>; Eric Dumazet
> > <[email protected]>; Jakub Kicinski <[email protected]>; Paolo Abeni
> > <[email protected]>
> > Cc: [email protected]; [email protected]; linux-
> > [email protected]
> > Subject: [Intel-wired-lan] [PATCH v3 iwl-net] igc: Fix trigger of
> > incorrect irq in igc_xsk_wakeup function
> >
> > Changes in v3:
> > - Added 'Fixes:' tags for the relevant commits.
> > - Added 'Reviewed-by:' tag from Jacob Keller.
> > - Updated subject line with '[iwl-net]' prefix.
> >
> > From 32422588358a537ef79de4ff630e4414e2c6b934 Mon Sep 17 00:00:00
> 2001
> > From: Vivek Behera <[email protected]>
> > Date: Fri, 5 Dec 2025 10:26:05 +0100
> > Subject: [PATCH v3 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 <[email protected]>
> > Reviewed-by: Jacob Keller <[email protected]>
> > ---
> >  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***/
Just a nit, I think it could be nice if you change multi-star to standard linux 
comments /* */

With the best regards
Alex

> > --
> > 2.34.1
> 
> Reviewed-by: Aleksandr Loktionov <[email protected]>

Reply via email to