Re: [PATCH net-next V2 1/3] net: Add max rate tx queue attribute

[David Miller <davem@davemloft.net>]

From: Or Gerlitz <ogerlitz@mellanox.com>
Date: Sun, 15 Mar 2015 15:03:14 +0200

> From: John Fastabend <john.r.fastabend@intel.com>
> 
> This adds a tx_maxrate attribute to the tx queue sysfs entry allowing
> for max-rate limiting. Along with DCB-ETS and BQL this provides another
> knob to tune queue performance. The limit units are Mbps.
> 
> By default it is disabled. To disable the rate limitation after it
> has been set for a queue, it should be set to zero.
> 
> Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
> Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
> ---
>  include/linux/netdevice.h |    9 ++++++
>  net/core/net-sysfs.c      |   67 +++++++++++++++++++++++++++++++++++++--------
>  2 files changed, 64 insertions(+), 12 deletions(-)
> 
> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
> index ddab1a2..0719307 100644
> --- a/include/linux/netdevice.h
> +++ b/include/linux/netdevice.h
> @@ -587,6 +587,7 @@ struct netdev_queue {
>  #ifdef CONFIG_BQL
>  	struct dql		dql;
>  #endif
> +	unsigned long		tx_maxrate;
>  } ____cacheline_aligned_in_smp;
>  
>  static inline int netdev_queue_numa_node_read(const struct netdev_queue *q)
> @@ -1025,6 +1026,11 @@ struct fib_info;
>   *	the set of features that the stack has calculated and it returns
>   *	those the driver believes to be appropriate.
>   *
> + *	int (*ndo_set_tx_maxrate)(struct net_device *dev,
> +				  int queue_index,
> +				  u32 maxrate);
> + *	Called when a user wants to set a max-rate limitation of specific
> + *	TX queue.

Every comment line you add should start with a "*" just like the rest
of the comment does.

You'll also need to re-spin this against net-next as the swdev_ops changes
that went in recently conflict.

Thanks.