Re: [net-next Patch] octeontx2-pf: Reuse Transmit queue/Send queue index of HTB class

[Simon Horman]

On Wed, May 08, 2024 at 12:39:35PM +0530, Hariprasad Kelam wrote:
> Real number of Transmit queues are incremented when user enables HTB
> class and vice versa. Depending on SKB priority driver returns transmit
> queue (Txq). Transmit queues and Send queues are one-to-one mapped.
> 
> In few scenarios, Driver is returning transmit queue value which is
> greater than real number of transmit queue and Stack detects this as
> error and overwrites transmit queue value.
> 
> For example
> user has added two classes and real number of queues are incremented
> accordingly
> - tc class add dev eth1 parent 1: classid 1:1 htb
>       rate 100Mbit ceil 100Mbit prio 1 quantum 1024
> - tc class add dev eth1 parent 1: classid 1:2 htb
>       rate 100Mbit ceil 200Mbit prio 7 quantum 1024
> 
> now if user deletes the class with id 1:1, driver decrements the real
> number of queues
> - tc class del dev eth1 classid 1:1
> 
> But for the class with id 1:2, driver is returning transmit queue
> value which is higher than real number of transmit queue leading
> to below error
> 
> eth1 selects TX queue x, but real number of TX queues is x
> 
> This patch solves the problem by assigning deleted class transmit
> queue/send queue to active class.
> 
> Signed-off-by: Hariprasad Kelam <hkelam@xxxxxxxxxxx>

Reviewed-by: Simon Horman <horms@xxxxxxxxxx>