Re: [dpdk-dev] [PATCH] net/mlx5: fix the drop action for the DR/DV

[Raslan Darawsheh <rasland@nvidia.com>]

Hi,

> -----Original Message-----
> From: Viacheslav Ovsiienko <viacheslavo@nvidia.com>
> Sent: Monday, April 5, 2021 12:59 PM
> To: dev@dpdk.org
> Cc: Raslan Darawsheh <rasland@nvidia.com>; Matan Azrad
> <matan@nvidia.com>; Ori Kam <orika@nvidia.com>; stable@dpdk.org
> Subject: [PATCH] net/mlx5: fix the drop action for the DR/DV
> 
> There are multiple branches in rdma-core library backing:
> the rte flows:
>   - Verbs
>   - Direct Verbs (DV)
>   - Direct Rules (DR)
> 
> The Verbs API always requires the specifying the queue even
> if there is the drop action in the flow, though the kernel
> optimizes out the actual queue usage for the flows containing
> the drop action. The PMD handles the dedicated Rx queue to
> provide Verbs API compatibility.
> 
> The DV/DR API does not require explicit specifying the queue
> at the flow creation, but PMD still specified the dedicated
> drop queue as action. It performed the packet forwarding to
> the dummy queue (that was not polled at all) causing the
> steering pipeline resources usage and degrading the overall
> packet processing rate. For example, with inserted flow to
> drop all the ingress packets the statistics reported only
> 15Mpps of 64B packets were received over 100Gbps line.
> 
> Since the Direct Rule API for E-Switch was introduced the
> rdma-core supports the dedicated drop action, that is recognized
> both for DV and DR and can be used for the entire device in
> unified fashion, regardless of steering domain. The similar drop
> action was introduced for E-Switch, the usage of this one can be
> extended for other steering domains, not for E-Switch's one only.
> 
> This patch:
>   - renames esw_drop_action to dr_drop_action to emphasize
>     the global nature of the variable (not only E-Switch domain)
>   - specifies this global drop action instead of dedicated
>     drop queue for the DR/DV flows
> 
> Cc: stable@dpdk.org
> Fixes: 34fa7c0268e7 ("net/mlx5: add drop action to Direct Verbs E-Switch")
> Fixes: 65b3cd0dc39b ("net/mlx5: create global drop action")
> 
> Signed-off-by: Viacheslav Ovsiienko <viacheslavo@nvidia.com>
> Acked-by: Matan Azrad <matan@nvidia.com>
> ---

Patch applied to next-net-mlx,

Kindest regards,
Raslan Darawsheh