Received-SPF: pass (google.com: domain of linux-kernel+bounces-99935-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) client-ip=2604:1380:4601:e00::3;
Date: Tue, 12 Mar 2024 10:05:22 +0200
From: Leon Romanovsky <leon@kernel.org>
To: Junxian Huang <huangjunxian6@hisilicon.com>
Cc: jgg@ziepe.ca, linux-rdma@vger.kernel.org, linuxarm@huawei.com,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH for-next] RDMA/hns: Support congestion control algorithm
 parameter configuration
Message-ID: <20240312080522.GO12921@unreal>
References: <20240308105443.1130283-1-huangjunxian6@hisilicon.com>
 <20240310100027.GC12921@unreal>
 <c16e3cc2-1a70-a9ec-e533-e508cfbab18e@hisilicon.com>
 <20240311071119.GH12921@unreal>
 <f8354762-703c-16e2-fa8e-bc8519fdcd06@hisilicon.com>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <f8354762-703c-16e2-fa8e-bc8519fdcd06@hisilicon.com>

On Mon, Mar 11, 2024 at 10:00:27PM +0800, Junxian Huang wrote:
> 
> 
> On 2024/3/11 15:11, Leon Romanovsky wrote:
> > On Mon, Mar 11, 2024 at 10:00:51AM +0800, Junxian Huang wrote:
> >>
> >>
> >> On 2024/3/10 18:00, Leon Romanovsky wrote:
> >>> On Fri, Mar 08, 2024 at 06:54:43PM +0800, Junxian Huang wrote:
> >>>> From: Chengchang Tang <tangchengchang@huawei.com>
> >>>>
> >>>> hns RoCE supports 4 congestion control algorithms. Each algorihm
> >>>> involves multiple parameters. Add port sysfs directory for each
> >>>> algorithm to allow modifying their parameters.
> >>>
> >>> Unless Jason changed his position after this rewrite [1], we don't allow
> >>> any custom driver sysfs code.
> >>>
> >>> [1] https://lore.kernel.org/all/cover.1623427137.git.leonro@nvidia.com/
> >>>
> >>
> >> I didn't quite get the reason from [1], could you please explain it?
> > 
> > Before [1], we didn't allow custom sysfs. After [1], the sysfs code
> > started to be more sane and usable for the drivers. However, it is
> > unlikely that the policy is changed to allow driver sysfs code.
> > 
> >>
> >> And it would be helpful if you could give us a hint about any other
> >> proper ways to do the algorithm parameter configuration.
> > 
> > Like any other FW internals.
> > 
> 
> If we add the capability of custom driver parameter configuration to
> rdmatool (similar to [2]), would it be acceptable?

Moshe's patch is for devlink. We are working on a generic solution for
other vendors to control/debug their devices.
https://lwn.net/Articles/955001/
https://lore.kernel.org/all/20240304160237.GA2909161@nvidia.com/

Feel free to join the discussion and reply that you are interested in
this proposal as well and emphasize that your device is not netdev at
all.

Thanks

> 
> [2] https://patchwork.ozlabs.org/project/netdev/patch/1530703837-24563-4-git-send-email-moshe@mellanox.com/
> 
> Junxian
> 
> > Thanks
> > 
> >>
> >> Thanks,
> >> Junxian
> >>
> >>>>
> >>>> Signed-off-by: Chengchang Tang <tangchengchang@huawei.com>
> >>>> Signed-off-by: Junxian Huang <huangjunxian6@hisilicon.com>
> >>>> ---
> >>>>  drivers/infiniband/hw/hns/Makefile          |   2 +-
> >>>>  drivers/infiniband/hw/hns/hns_roce_device.h |  20 ++
> >>>>  drivers/infiniband/hw/hns/hns_roce_hw_v2.c  |  59 ++++
> >>>>  drivers/infiniband/hw/hns/hns_roce_hw_v2.h  | 132 ++++++++
> >>>>  drivers/infiniband/hw/hns/hns_roce_main.c   |   3 +
> >>>>  drivers/infiniband/hw/hns/hns_roce_sysfs.c  | 346 ++++++++++++++++++++
> >>>>  6 files changed, 561 insertions(+), 1 deletion(-)
> >>>>  create mode 100644 drivers/infiniband/hw/hns/hns_roce_sysfs.c
> >>>
> >>> Thanks
> >>