[prev in list] [next in list] [prev in thread] [next in thread] 

List:       dpdk-dev
Subject:    Re: [dpdk-dev] [PATCH v15 4/7] drivers/net: update Rx RSS hash	offload capabilities
From:       Pavan Nikhilesh Bhagavatula <pbhagavatula () marvell ! com>
Date:       2019-10-31 16:51:29
Message-ID: CY4PR1801MB186335944DC7EA6F955BD744DE630 () CY4PR1801MB1863 ! namprd18 ! prod ! outlook ! com
[Download RAW message or body]



>-----Original Message-----
>From: dev <dev-bounces@dpdk.org> On Behalf Of Thomas Monjalon
>Sent: Thursday, October 31, 2019 7:33 PM
>To: Pavan Nikhilesh Bhagavatula <pbhagavatula@marvell.com>
>Cc: dev@dpdk.org; ferruh.yigit@intel.com;
>arybchenko@solarflare.com; Jerin Jacob Kollanukkaran
><jerinj@marvell.com>; Ajit Khaparde <ajit.khaparde@broadcom.com>;
>Somnath Kotur <somnath.kotur@broadcom.com>; Rahul Lakkireddy
><rahul.lakkireddy@chelsio.com>; Hemant Agrawal
><hemant.agrawal@nxp.com>; Sachin Saxena
><sachin.saxena@nxp.com>; Wenzhuo Lu <wenzhuo.lu@intel.com>;
>John Daley <johndale@cisco.com>; Hyong Youb Kim
><hyonkim@cisco.com>; Qi Zhang <qi.z.zhang@intel.com>; Xiao Wang
><xiao.w.wang@intel.com>; Ziyang Xuan <xuanziyang2@huawei.com>;
>Xiaoyun Wang <cloud.wangxiaoyun@huawei.com>; Guoyang Zhou
><zhouguoyang@huawei.com>; Beilei Xing <beilei.xing@intel.com>;
>Jingjing Wu <jingjing.wu@intel.com>; Qiming Yang
><qiming.yang@intel.com>; Konstantin Ananyev
><konstantin.ananyev@intel.com>; Shijith Thotton
><sthotton@marvell.com>; Srisivasubramanian Srinivasan
><srinivasan@marvell.com>; Matan Azrad <matan@mellanox.com>;
>Shahaf Shuler <shahafs@mellanox.com>; Viacheslav Ovsiienko
><viacheslavo@mellanox.com>; Stephen Hemminger
><sthemmin@microsoft.com>; K. Y. Srinivasan <kys@microsoft.com>;
>Haiyang Zhang <haiyangz@microsoft.com>; Alejandro Lucero
><alejandro.lucero@netronome.com>; Nithin Kumar Dabilpuram
><ndabilpuram@marvell.com>; Kiran Kumar Kokkilagadda
><kirankumark@marvell.com>; Rasesh Mody <rmody@marvell.com>;
>Shahed Shaikh <shshaikh@marvell.com>; Maciej Czekaj
><mczekaj@marvell.com>; Yong Wang <yongwang@vmware.com>
>Subject: Re: [dpdk-dev] [PATCH v15 4/7] drivers/net: update Rx RSS
>hash offload capabilities
>
>29/10/2019 16:37, pbhagavatula@marvell.com:
>> From: Pavan Nikhilesh <pbhagavatula@marvell.com>
>>
>> Add DEV_RX_OFFLOAD_RSS_HASH flag for all PMDs that support RSS
>hash
>> delivery.
>>
>> Signed-off-by: Pavan Nikhilesh <pbhagavatula@marvell.com>
>> Reviewed-by: Andrew Rybchenko <arybchenko@solarflare.com>
>> Reviewed-by: Hemant Agrawal <hemant.agrawal@nxp.com>
>> Acked-by: Jerin Jacob <jerinj@marvell.com>
>> Acked-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
>> ---
>> +	if (!(dev->data->dev_conf.rxmode.offloads &
>DEV_RX_OFFLOAD_RSS_HASH))
>> +		dev->data->dev_conf.rxmode.offloads |=
>DEV_RX_OFFLOAD_RSS_HASH;
>
>Excuse me, I miss why you need a check before setting the bit.

Currently, none of the PMDs support disabling RSS_HASH (except octeontx2) since it involves 
adding an if check in Rx routine that might lead to perf impact.
So, we are implicitly enabling the offload for all the PMDs if an application decides to disable
RSS_HASH. In future if PMD maintainer decides to add this feature she/he can remove the check.

>

[prev in list] [next in list] [prev in thread] [next in thread]