From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754725AbcBVQid (ORCPT ); Mon, 22 Feb 2016 11:38:33 -0500 Received: from userp1040.oracle.com ([156.151.31.81]:26118 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754595AbcBVQia (ORCPT ); Mon, 22 Feb 2016 11:38:30 -0500 Subject: Re: [net-next][PATCH 11/13] RDS: IB: add Fastreg MR (FRMR) detection support To: Bart Van Assche , David Miller References: <1455967804-27644-1-git-send-email-santosh.shilimkar@oracle.com> <1455967804-27644-12-git-send-email-santosh.shilimkar@oracle.com> <20160221.223656.2213596964617869651.davem@davemloft.net> <56CB2B7E.5000402@sandisk.com> Cc: netdev@vger.kernel.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org From: santosh shilimkar Organization: Oracle Corporation Message-ID: <56CB397D.1030603@oracle.com> Date: Mon, 22 Feb 2016 08:38:21 -0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <56CB2B7E.5000402@sandisk.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-Source-IP: aserv0022.oracle.com [141.146.126.234] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2/22/2016 7:38 AM, Bart Van Assche wrote: > On 02/21/16 19:36, David Miller wrote: >> From: Santosh Shilimkar >> Date: Sat, 20 Feb 2016 03:30:02 -0800 >> >>> @@ -54,6 +55,8 @@ module_param(rds_ib_mr_8k_pool_size, int, 0444); >>> MODULE_PARM_DESC(rds_ib_mr_8k_pool_size, " Max number of 8K mr per >>> HCA"); >>> module_param(rds_ib_retry_count, int, 0444); >>> MODULE_PARM_DESC(rds_ib_retry_count, " Number of hw retries before >>> reporting an error"); >>> +module_param(prefer_frmr, bool, 0444); >>> +MODULE_PARM_DESC(prefer_frmr, "Preferred MR method if both FMR and >>> FRMR supported"); >> >> Sorry, you're going to have to create a real run time method to configure >> this parameter. >> >> I'm strongly against module parameters. >> >> Please don't go into details about why this might be difficult to do, >> I'm totally not interested. Doing things properly is sometimes not >> easy, that's life. > Sure Dave. Will drop the parameter. The runtime detection is already in place. When an HCA hardware supports both FMR and FRMR features, parameter can be used as over-ride over a default selection. > Hello Santosh, > > What is the purpose of the prefer_frmr kernel module parameter ? Is this > a parameter that is useful to RDS users or is its only purpose to allow > developers of the RDS module to test both the FMR and FRMR code paths on > hardware that supports both MR methods ? > Right. Since FRMR in early phase still for RDS, it was useful on HCA's which supports both registration methods. Its not a deal breaker so am going to drop the parameter as mentioned above. Regards, Santosh