From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id 2406744037; Wed, 15 May 2024 17:04:40 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 06846402E5; Wed, 15 May 2024 17:04:40 +0200 (CEST) Received: from mail-pl1-f180.google.com (mail-pl1-f180.google.com [209.85.214.180]) by mails.dpdk.org (Postfix) with ESMTP id 2C6DE402D7 for ; Wed, 15 May 2024 17:04:38 +0200 (CEST) Received: by mail-pl1-f180.google.com with SMTP id d9443c01a7336-1ee12baa01cso57819145ad.0 for ; Wed, 15 May 2024 08:04:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=networkplumber-org.20230601.gappssmtp.com; s=20230601; t=1715785477; x=1716390277; darn=dpdk.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:from:to:cc:subject:date :message-id:reply-to; bh=C8g8n/ghZWmF0DTCAfemFqJSB0PBhddg+JByErt6Vdc=; b=Ud9EMu0vd47a8eQ17jCX9DRC18GgRyTUWfHqFQwlOM+cJVF9S4QffZzRCon5WyJhsf ApK2ShGtCgcxN/Dg2MfXZUKXK89oF/o2WiXQM5d+pW8WHChkkxp0PQ+dygKrZAVsYhS+ w8dpAFYUd4ciNe0xCZBbh3035N2/pP0Duq+icdB833mQOZItovbZHu8Yl3j6V6eh3g7b D8tfSF5xkNpFJ/kTMNdqW0LcoCAIom4AH6zBSgn4nOskG9FdmQEfynDZbuFDRw7uLh+Q U2b6vK3zKvHCNnywsK2m+4awmbZIxLQFQEsfSlH+pQQLulakbEmzuw1zh+fZD2kkZ3kn dFfw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1715785477; x=1716390277; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:subject:cc:to:from:date:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=C8g8n/ghZWmF0DTCAfemFqJSB0PBhddg+JByErt6Vdc=; b=ZQGDT4yhYdlNl5EVY077/6OH8b7+mjrQfVoF/pPTzz4D69upA2VcB5WptTRevmbjO0 /3iYWSqUjGe7OqFbSXebhYyBEXouHRokjpn0zH5ZAk4gGOskhvXY9aBfUM0bpjMMJa7T W6L1Y4BtBfLcWdhb1ErbzCSeytcLCa3IyBdywxz4GKpX0TtI+AOIOo962b0RrELQgqd6 1bWzqV5NpyuVcIoqa2dLwIL2QDGlrn4Wx7FTXtWJc+PiSH68ePICX1YgXp5Syyxqu5fi bBqsTZ/WiD0s6NPSZ1f8MCwNzr+ENuQD+DsjOpoH907y6pZqVSAuhnwwgLjTLsYH2fyf GAaA== X-Gm-Message-State: AOJu0YwIj2iucYG+gXoAks6RgygAdKLp6DTtgwPL01Sb+HRpXJhz9kpd gA6QInZmfj/+ZMXyAqopNsHHHuscs3OiaxQOU0E16ayDSpRluhaqMM1fgHRf4as= X-Google-Smtp-Source: AGHT+IESiIO3xL2s++mFWj91XEe+h6eFFmgHBAP4g0sAycDzGuzW7EL1EFbq72a77CdtZ2BuITRNRQ== X-Received: by 2002:a17:90b:4a86:b0:2b5:f6d0:98cb with SMTP id 98e67ed59e1d1-2b6cd1eaf0emr14527927a91.40.1715785477127; Wed, 15 May 2024 08:04:37 -0700 (PDT) Received: from hermes.local (204-195-96-226.wavecable.com. [204.195.96.226]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-2b6710564bfsm11886787a91.12.2024.05.15.08.04.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 15 May 2024 08:04:36 -0700 (PDT) Date: Wed, 15 May 2024 08:04:34 -0700 From: Stephen Hemminger To: Nagesh Mallappa Cc: dev@dpdk.org Subject: Re: RSS Hash value returned by the gvnic pmd dpdk driver not matching Toeplitz Message-ID: <20240515080434.33abfd44@hermes.local> In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org On Wed, 15 May 2024 13:50:38 +0530 Nagesh Mallappa wrote: > Hi Team, > > We are using a C3 GCP instance having GVNIC with DPDK enabled. > We are using latest version of DPDK ( dpdk-24.03 ) to configure RSS key, we > understand C3 GCP instance with gvnic supports Toeplitz rss algorithm ( > Reference - > https://github.com/google/compute-virtual-ethernet-dpdk/blob/main/gve_ethdev.c > ), > but we are hitting below issue. > > *Problem Statement - The RSS Hash value returned by the gvnic driver is > different and is not matching the one computed by Toeplitz.* > > Using below script to compute rss hash value from Toeplitz. > (https://gist.github.com/joongh/16867705b03b49e393cbf91da3cb42a7) > > Consider below data to compute RSS Hash value - > > Source IP - 79.124.62.122 > Destination IP - 192.168.7.28 > Source Port - 49442 > Destination Port - 55327 > RSS Key - {0x94e3e97e, 0x4abac401, 0x1e0edbf, 0xe059e1f4, 0xb6e27dff, > 0xdf55c916, 0xe9e6e4db, 0x1f9fb82c, 0x1e0edbf, 0xe059e1f4} > > *Hash Value returned by Toeplitz - 0x8bbafd0f* > > Gvnic dpdk pmd driver which uses Toeplitz RSS hash algorithm too is > expected to compute above RSS Hash value but we see the Hash value stored > in dpdk mbuf to be 0xc6a15941 which is not right. > From the DPDK side we have ensured RSS offloading configuration is done > appropriately, but still we are seeing above mismatch. > > We request you to please help us understand why this mismatch is happening > and is this expected behavior of gvnic on C3 instance. Could you see if it is a driver byte order issue by byteswapping the key?