Re: [PATCH net-next 2/6] net: introduce a trivial netdev_queue_config()

[Subbaraya Sundeep <sbhatta@marvell.com>]

On 2026-01-22 at 06:21:09, Jakub Kicinski (kuba@kernel.org) wrote:
> We may choose to extend or reimplement the logic which renders
> the per-queue config. The drivers should not poke directly into
> the queue state. Add a helper for drivers to use when they want
> to query the config for a specific queue.
> 
> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
> ---
>  net/core/Makefile                         |  1 +
>  include/net/netdev_queues.h               |  3 +++
>  drivers/net/ethernet/broadcom/bnxt/bnxt.c |  6 ++---
>  net/core/netdev_config.c                  | 32 +++++++++++++++++++++++
>  4 files changed, 39 insertions(+), 3 deletions(-)
>  create mode 100644 net/core/netdev_config.c
> 
> diff --git a/net/core/Makefile b/net/core/Makefile
> index 9ef2099c5426..d643a5a7fd18 100644
> --- a/net/core/Makefile
> +++ b/net/core/Makefile
> @@ -19,6 +19,7 @@ obj-$(CONFIG_NETDEV_ADDR_LIST_TEST) += dev_addr_lists_test.o
>  
>  obj-y += net-sysfs.o
>  obj-y += hotdata.o
> +obj-y += netdev_config.o
>  obj-y += netdev_rx_queue.o
>  obj-y += netdev_queues.o
>  obj-$(CONFIG_PAGE_POOL) += page_pool.o page_pool_user.o
> diff --git a/include/net/netdev_queues.h b/include/net/netdev_queues.h
> index 2ab3eae8e8c3..725bf69ef86c 100644
> --- a/include/net/netdev_queues.h
> +++ b/include/net/netdev_queues.h
> @@ -170,6 +170,9 @@ struct netdev_queue_mgmt_ops {
>  	unsigned int supported_params;
>  };
>  
> +void netdev_queue_config(struct net_device *dev, int rxq,
> +			 struct netdev_queue_config *qcfg);
> +
Minor nit: make function name something like netdev_get_queue_config
(to avoid same as struct name)

Thanks,
Sundeep

>  bool netif_rxq_has_unreadable_mp(struct net_device *dev, int idx);
>  
>  /**
> diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> index 0b95100a7c36..d57e833ce690 100644
> --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
> @@ -4326,12 +4326,12 @@ static void bnxt_init_ring_struct(struct bnxt *bp)
>  
>  	for (i = 0; i < bp->cp_nr_rings; i++) {
>  		struct bnxt_napi *bnapi = bp->bnapi[i];
> +		struct netdev_queue_config qcfg;
>  		struct bnxt_ring_mem_info *rmem;
>  		struct bnxt_cp_ring_info *cpr;
>  		struct bnxt_rx_ring_info *rxr;
>  		struct bnxt_tx_ring_info *txr;
>  		struct bnxt_ring_struct *ring;
> -		struct netdev_rx_queue *rxq;
>  
>  		if (!bnapi)
>  			continue;
> @@ -4349,8 +4349,8 @@ static void bnxt_init_ring_struct(struct bnxt *bp)
>  		if (!rxr)
>  			goto skip_rx;
>  
> -		rxq = __netif_get_rx_queue(bp->dev, i);
> -		rxr->rx_page_size = rxq->qcfg.rx_page_size;
> +		netdev_queue_config(bp->dev, i, &qcfg);
> +		rxr->rx_page_size = qcfg.rx_page_size;
>  
>  		ring = &rxr->rx_ring_struct;
>  		rmem = &ring->ring_mem;
> diff --git a/net/core/netdev_config.c b/net/core/netdev_config.c
> new file mode 100644
> index 000000000000..562087bd30c8
> --- /dev/null
> +++ b/net/core/netdev_config.c
> @@ -0,0 +1,32 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +
> +#include <linux/netdevice.h>
> +#include <net/netdev_queues.h>
> +#include <net/netdev_rx_queue.h>
> +
> +/**
> + * netdev_queue_config() - get configuration for a given queue
> + * @dev:      net_device instance
> + * @rxq_idx:  index of the queue of interest
> + * @qcfg: queue configuration struct (output)
> + *
> + * Render the configuration for a given queue. This helper should be used
> + * by drivers which support queue configuration to retrieve config for
> + * a particular queue.
> + *
> + * @qcfg is an output parameter and is always fully initialized by this
> + * function. Some values may not be set by the user, drivers may either
> + * deal with the "unset" values in @qcfg, or provide the callback
> + * to populate defaults in queue_management_ops.
> + */
> +void netdev_queue_config(struct net_device *dev, int rxq_idx,
> +			 struct netdev_queue_config *qcfg)
> +{
> +	struct netdev_queue_config *stored;
> +
> +	memset(qcfg, 0, sizeof(*qcfg));
> +
> +	stored = &__netif_get_rx_queue(dev, rxq_idx)->qcfg;
> +	qcfg->rx_page_size = stored->rx_page_size;
> +}
> +EXPORT_SYMBOL(netdev_queue_config);
> -- 
> 2.52.0
>