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=-5.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 9C1C8CA9EAE for ; Tue, 29 Oct 2019 19:51:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6334A20659 for ; Tue, 29 Oct 2019 19:51:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b="UTgrs2sE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726462AbfJ2TvE (ORCPT ); Tue, 29 Oct 2019 15:51:04 -0400 Received: from mail-qk1-f195.google.com ([209.85.222.195]:43417 "EHLO mail-qk1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725870AbfJ2TvD (ORCPT ); Tue, 29 Oct 2019 15:51:03 -0400 Received: by mail-qk1-f195.google.com with SMTP id a194so78605qkg.10 for ; Tue, 29 Oct 2019 12:51:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=cQkD4MvS0kKW1/ul+xB5LN/x1F0/sjmZ3GaEB4sIcXA=; b=UTgrs2sEctwlidoemzTmSe3mg08J8lodDl8CYJjVTOFTT+YNjsbAdL/GBeqMFfnB0l URtqgGALgtypK14/rZfHTviUq1QdHn+pD6y+O+SbVT+Ri9fp0oVJLCL30ZyW+ZV7GF/2 YAKog5d4ob6JulurRIoW80FwREVYBbDEKVeKM/c/hCMBHh5QTy1doYCBSUG3M1H7uidE RU8VpQQPZm49g02i6f/9IgGaAP8yJsA5GqT/hGq96XsPzJuGWbltrYTTe/ncqPqIyBGe uxfsHVTkc181cbNhqYo7YcmffiBnz+Te8Kb9Nq3MsuE90VUkKzHADyLLt2yWtaWlz3aN IFqQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to:user-agent; bh=cQkD4MvS0kKW1/ul+xB5LN/x1F0/sjmZ3GaEB4sIcXA=; b=dlY0eUkioh+oug4AEbpAelLxo4KrY4gD9orEsfQAakaEv9XnU2xvuvZxGWdJ96DarM 2Hfs0xITZp18+GHLm+1dIeV9JmXthhqA8EC/8QWHRSShIptkFYUrfjK38Th2Y4ay2Oov 6inuA49UiCdw7wt2SFiLPCcHwFthvmi35FuAUz8Z78jqiS/B2/ap3UH2/zuHMhIvJN+l 8F19DaFU0uWIh+ky/FFQ0F2Rx0OVfpznENovUvQduSozp8wzSDTVXLmPpSoybjlfNABU LbXKGJDF9WROW6wALKw0UjDugXNPmRcq+Ztzam5t5HcRor1BdRJM6mdf1tscgSnmZgjF lKqA== X-Gm-Message-State: APjAAAWastKWG5UVKBMtyzKLiSHvYYMoz7WafvwRkKadjRU095O3Y0Xc bgGAmpV3DcH1zRYocx3RT/syEg== X-Google-Smtp-Source: APXvYqwbJHyN8T+1UJD2wSYLRC6t1gVRWzQx3yuUuIdBzMtowjw0Nf3NT4k6ar6ntJVDgExf62sS1w== X-Received: by 2002:a37:8046:: with SMTP id b67mr24024593qkd.437.1572378662716; Tue, 29 Oct 2019 12:51:02 -0700 (PDT) Received: from ziepe.ca (hlfxns017vw-142-162-113-180.dhcp-dynamic.fibreop.ns.bellaliant.net. [142.162.113.180]) by smtp.gmail.com with ESMTPSA id g45sm4240565qtb.48.2019.10.29.12.51.02 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 29 Oct 2019 12:51:02 -0700 (PDT) Received: from jgg by mlx.ziepe.ca with local (Exim 4.90_1) (envelope-from ) id 1iPXW9-0000Rd-PJ; Tue, 29 Oct 2019 16:51:01 -0300 Date: Tue, 29 Oct 2019 16:51:01 -0300 From: Jason Gunthorpe To: Dag Moxnes Cc: dledford@redhat.com, leon@kernel.org, parav@mellanox.com, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH rdma-next] RDMA/cma: Use ACK timeout for RoCE packetLifeTime Message-ID: <20191029195101.GA1654@ziepe.ca> References: <1572003721-26368-1-git-send-email-dag.moxnes@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1572003721-26368-1-git-send-email-dag.moxnes@oracle.com> User-Agent: Mutt/1.9.4 (2018-02-28) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 25, 2019 at 01:42:01PM +0200, Dag Moxnes wrote: > The cma is currently using a hard-coded value, CMA_IBOE_PACKET_LIFETIME, > for the PacketLifeTime, as it can not be determined from the network. > This value might not be optimal for all networks. > > The cma module supports the function rdma_set_ack_timeout to set the > ACK timeout for a QP associated with a connection. As per IBTA 12.7.34 > local ACK timeout = (2 * PacketLifeTime + Local CA’s ACK delay). > Assuming a negligible local ACK delay, we can use > PacketLifeTime = local ACK timeout/2 > as a reasonable approximation for RoCE networks. > > Signed-off-by: Dag Moxnes > Change-Id: I200eda9d54829184e556c3c55d6a8869558d76b2 Please don't send Change-Id to the public lists. Run checkpatch before sending. Otherwise this seems reasonable to me.. Jason