Subject: Re: [PATCH net-next v4 06/10] net: airoha: Move {cpu,fwd}_tx_packets in airoha_qdma struct

From: Lorenzo Bianconi <[email-masked]>
Date: Sat, 9 May 2026 14:14:40 +0200

On May 07, Lorenzo Bianconi wrote:
> Since now multiple net_devices connected to different QDMA blocks can
> share the same GDM port, cpu_tx_packets and fwd_tx_packets fields can
> be overwritten with the value from a different QDMA block. In order to
> fix the issue move cpu_tx_packets and fwd_tx_packets fields from
> airoha_gdm_port struct to airoha_qdma one.
> 
> Signed-off-by: Lorenzo Bianconi <[email-masked]>
> ---
>  drivers/net/ethernet/airoha/airoha_eth.c | 15 +++++++--------
>  drivers/net/ethernet/airoha/airoha_eth.h |  8 ++++----
>  2 files changed, 11 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/net/ethernet/airoha/airoha_eth.c b/drivers/net/ethernet/airoha/airoha_eth.c
> index 69a4c2e0d58b..786bc677af3c 100644
> --- a/drivers/net/ethernet/airoha/airoha_eth.c
> +++ b/drivers/net/ethernet/airoha/airoha_eth.c
> @@ -2306,19 +2306,18 @@ static int airoha_qdma_get_tx_ets_stats(struct net_device *netdev, int channel,
>  					struct tc_ets_qopt_offload *opt)
>  {
>  	struct airoha_gdm_dev *dev = netdev_priv(netdev);
> -	struct airoha_gdm_port *port = dev->port;
> +	struct airoha_qdma *qdma = dev->qdma;
>  
> -	u64 cpu_tx_packets = airoha_qdma_rr(dev->qdma,
> -					    REG_CNTR_VAL(channel << 1));
> -	u64 fwd_tx_packets = airoha_qdma_rr(dev->qdma,
> +	u64 cpu_tx_packets = airoha_qdma_rr(qdma, REG_CNTR_VAL(channel << 1));
> +	u64 fwd_tx_packets = airoha_qdma_rr(qdma,
>  					    REG_CNTR_VAL((channel << 1) + 1));
> -	u64 tx_packets = (cpu_tx_packets - port->cpu_tx_packets) +
> -			 (fwd_tx_packets - port->fwd_tx_packets);
> +	u64 tx_packets = (cpu_tx_packets - qdma->cpu_tx_packets) +
> +			 (fwd_tx_packets - qdma->fwd_tx_packets);
>  
>  	_bstats_update(opt->stats.bstats, 0, tx_packets);
>  
> -	port->cpu_tx_packets = cpu_tx_packets;
> -	port->fwd_tx_packets = fwd_tx_packets;
> +	qdma->cpu_tx_packets = cpu_tx_packets;
> +	qdma->fwd_tx_packets = fwd_tx_packets;
>  
>  	return 0;
>  }
> diff --git a/drivers/net/ethernet/airoha/airoha_eth.h b/drivers/net/ethernet/airoha/airoha_eth.h
> index 34f1fef51640..3e93919a175c 100644
> --- a/drivers/net/ethernet/airoha/airoha_eth.h
> +++ b/drivers/net/ethernet/airoha/airoha_eth.h
> @@ -533,6 +533,10 @@ struct airoha_qdma {
>  	struct airoha_queue q_rx[AIROHA_NUM_RX_RING];
>  
>  	DECLARE_BITMAP(qos_sq_bmap, AIROHA_NUM_QOS_CHANNELS);
> +
> +	/* qos stats counters */
> +	u64 cpu_tx_packets;
> +	u64 fwd_tx_packets;
>  };
>  
>  struct airoha_gdm_dev {
> @@ -549,10 +553,6 @@ struct airoha_gdm_port {
>  
>  	struct airoha_hw_stats stats;
>  
> -	/* qos stats counters */
> -	u64 cpu_tx_packets;
> -	u64 fwd_tx_packets;
> -
>  	struct metadata_dst *dsa_meta[AIROHA_MAX_DSA_PORTS];
>  };
>  
> 
> -- 
> 2.54.0

commenting on sashiko report:
https://sashiko.dev/#/patchset/20260507-airoha-eth-multi-serdes-v4-0-af613b61ae02%40kernel.org

- Will this cause statistics to be stolen between net_devices sharing the same QDMA block?
  - I will fix it in v5 moving counters in airoha_gdm_dev