From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B94C0C2D0E3 for ; Fri, 11 Sep 2020 14:28:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 71AF7222B9 for ; Fri, 11 Sep 2020 14:28:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599834481; bh=LiMZOsK2jgyrdk6XGz+CscC5BHrMcAUHMeRXxr5Vn0I=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=K6JGx8kOEN5HYrNrwXQ27JG3oufNjyXMsBcIbHQBiLD5+GgVKlSeRVgAPJq2tFF/C 9qxU3rGnPhpTqJVpNWBuXitqc9L5IGWnb7I/+41DBK+qH4o0EqHUOlsluxNLKZWiCz Bqh6VrYMJ9VS/MqCCk+lXDiJVynd/XJ+q7CWbbrI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726196AbgIKO13 (ORCPT ); Fri, 11 Sep 2020 10:27:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:57720 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726084AbgIKNMA (ORCPT ); Fri, 11 Sep 2020 09:12:00 -0400 Received: from localhost (unknown [213.57.247.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 6553C224B1; Fri, 11 Sep 2020 13:11:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599829917; bh=LiMZOsK2jgyrdk6XGz+CscC5BHrMcAUHMeRXxr5Vn0I=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=JWzeKvHlCOL4QT+4uSzahXj7EzDXD3UFNyy5OegvAfRGL6wZIMbfpPI6MrPjIs/E7 iNp/bq5iBloIeICEHGqSfazSznR9xtpiopYSe1ms0Qj16ulx6j7Dww1Ba7KG7qeSSw WC6gxtukQoOxl/mp8uFTtOpSWlYJemxuuko7MFM8= Date: Fri, 11 Sep 2020 16:11:52 +0300 From: Leon Romanovsky To: Potnuri Bharat Teja Cc: "jgg@ziepe.ca" , "dledford@redhat.com" , "linux-rdma@vger.kernel.org" Subject: Re: [PATCH] RDMA/iw_cxgb4: disable delayed ack by default Message-ID: <20200911131152.GM421756@unreal> References: <20200909134726.10348-1-bharat@chelsio.com> <20200910122739.GJ421756@unreal> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Thu, Sep 10, 2020 at 07:14:50PM +0000, Potnuri Bharat Teja wrote: > >> Subject: [PATCH] RDMA/iw_cxgb4: disable delayed ack by default > >> > >> Receive side delayed ack mode is needed only for certain area networks/ connections. Therefore disable it by default. > >> > >> Signed-off-by: Potnuri Bharat Teja > >> --- > >> drivers/infiniband/hw/cxgb4/cm.c | 4 ++-- > >> 1 file changed, 2 insertions(+), 2 deletions(-) > >> > >> diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c > >> index 1f288c73ccfc..8769e7aa097f 100644 > >> --- a/drivers/infiniband/hw/cxgb4/cm.c > >> +++ b/drivers/infiniband/hw/cxgb4/cm.c > >> @@ -77,9 +77,9 @@ static int enable_ecn; module_param(enable_ecn, int, 0644); MODULE_PARM_DESC(enable_ecn, "Enable ECN (default=0/disabled)"); > >> > >> -static int dack_mode = 1; > >> +static int dack_mode; > >> module_param(dack_mode, int, 0644); > >> -MODULE_PARM_DESC(dack_mode, "Delayed ack mode (default=1)"); > >> +MODULE_PARM_DESC(dack_mode, "Delayed ack mode (default=0)"); > > > >Are you sure that this doesn't break user scripts? > Yes, I am sure. This does not interfere with user/kernel RDMA functionalities. How is it possible? Before this change user that did "modprobe iw_cxgb4" had delayed mode enabled, after this he will need to issue "modprobe iw_cxgb4 dack_mode=1" https://github.com/linux-rdma/rdma-core/blob/master/kernel-boot/rdma-hw-modules.rules#L12 Thanks > > Thanks, > Bharat. > > > >Thanks > > > >> > >> uint c4iw_max_read_depth = 32; > >> module_param(c4iw_max_read_depth, int, 0644); > >> -- > >> 2.24.0