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 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 41C95C46CA3 for ; Sun, 10 Dec 2023 05:32:27 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rCCPE-0002in-L8; Sun, 10 Dec 2023 00:31:08 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rCCPA-0002ZD-2F for qemu-devel@nongnu.org; Sun, 10 Dec 2023 00:31:04 -0500 Received: from mail-oi1-x22d.google.com ([2607:f8b0:4864:20::22d]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1rCCP7-0003Hh-Qu for qemu-devel@nongnu.org; Sun, 10 Dec 2023 00:31:03 -0500 Received: by mail-oi1-x22d.google.com with SMTP id 5614622812f47-3b9d2b8c3c6so2507566b6e.1 for ; Sat, 09 Dec 2023 21:31:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=daynix-com.20230601.gappssmtp.com; s=20230601; t=1702186260; x=1702791060; darn=nongnu.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=Qvzil6Rk6oklx2iI721eED0u1hPwR1TQxrt5QVmBpVY=; b=ddH+qPCupfCJuZIue3Jw5I1SpaGglUYrLK8SSi/mwZVGz8poQiDkmnleUdrkhosm3Q eoN2nqcbBVVTohj9GfwbLSYPXJg43D/bJyBkKGsRDmIasvPk55e9Y0DN7Y5CsxBTFYp8 nG8/8ZdF5nCu2fGx25DuL/BlzkkQhPmjn/kdTF1xguqjO7L3fEQyAo5xcy9G4vVbdJl2 6yNzxcspXf0vxx3im6JmsBQTJGFGfD8u/Wo8YJi2mVGPA3r3cdrAr4m/yOwlDs3f2WSU sh5MsHwzOMi2vqOrKpp//3NFfLmnyN+1DWrTrajvGsy1bu5DUhyr/439QVQmYE72Mu/9 kxBg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1702186260; x=1702791060; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=Qvzil6Rk6oklx2iI721eED0u1hPwR1TQxrt5QVmBpVY=; b=lWBGNTgGKfRcdgfHkyj7w9DaRDpvPR+h+iDCVlKXFPojyISaLLNmp4vocFf/wIbJkz SlcBRbGnNP8cA66PoqsLGSOo3XgUF8piVdw5qKuWfdnp6LXIpRWn9HdxFnp1Md2AHXAu A0/VaJubCbezI2AonplnKdzxXfiw+KXYdEokBtUG7WfKl1/fNsL/qQ1U+ecKAWuYvHOG N8Sb3V76oxBRJsbDuQMWSZWkixl/5n29d0u01Mkn32J4DtrdBzBPgLb0zQwrpUq3h86J YGNQ4FdNS0CYK8VgDkLlOzhrqsIHbt9rjYZfIvC2rdDb3NU2jpHnn73fqkDj+j/CeylT 8zWA== X-Gm-Message-State: AOJu0YzrsiD/r9bzs40j6C3pNdjOMsVe+YAe0lI6W+RTkBHc/1+7SNxt uv7ERucZ/6Ij7a4Ds4nyp0L0Yg== X-Google-Smtp-Source: AGHT+IHuLRctEot59aVpPsOCYWJJpaBm9kWy3twRpngIcewUeO5jybw0ZVPQP3vbprsU2J193AedmA== X-Received: by 2002:a05:6808:2225:b0:3b8:bb95:97ef with SMTP id bd37-20020a056808222500b003b8bb9597efmr3084867oib.48.1702186260661; Sat, 09 Dec 2023 21:31:00 -0800 (PST) Received: from localhost ([157.82.205.15]) by smtp.gmail.com with UTF8SMTPSA id m9-20020a170902db0900b001d06b93c66dsm4206712plx.233.2023.12.09.21.30.58 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sat, 09 Dec 2023 21:31:00 -0800 (PST) From: Akihiko Odaki Date: Sun, 10 Dec 2023 14:29:52 +0900 Subject: [PATCH v8 14/19] ebpf: Fix RSS error handling MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20231210-rss-v8-14-9553ee714d38@daynix.com> References: <20231210-rss-v8-0-9553ee714d38@daynix.com> In-Reply-To: <20231210-rss-v8-0-9553ee714d38@daynix.com> To: Jason Wang , Dmitry Fleytman , Sriram Yagnaraman , "Michael S. Tsirkin" , Luigi Rizzo , Giuseppe Lettieri , Vincenzo Maffione , Andrew Melnychenko , Yuri Benditovich Cc: qemu-devel@nongnu.org, Akihiko Odaki X-Mailer: b4 0.12.4 Received-SPF: none client-ip=2607:f8b0:4864:20::22d; envelope-from=akihiko.odaki@daynix.com; helo=mail-oi1-x22d.google.com X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_NONE=0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org calculate_rss_hash() was using hash value 0 to tell if it calculated a hash, but the hash value may be 0 on a rare occasion. Have a distinct bool value for correctness. Fixes: f3fa412de2 ("ebpf: Added eBPF RSS program.") Signed-off-by: Akihiko Odaki --- tools/ebpf/rss.bpf.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/tools/ebpf/rss.bpf.c b/tools/ebpf/rss.bpf.c index 20f227e2ac..667ea6899e 100644 --- a/tools/ebpf/rss.bpf.c +++ b/tools/ebpf/rss.bpf.c @@ -377,18 +377,19 @@ error: return err; } -static inline __u32 calculate_rss_hash(struct __sk_buff *skb, - struct rss_config_t *config, struct toeplitz_key_data_t *toe) +static inline bool calculate_rss_hash(struct __sk_buff *skb, + struct rss_config_t *config, + struct toeplitz_key_data_t *toe, + __u32 *result) { __u8 rss_input[HASH_CALCULATION_BUFFER_SIZE] = {}; size_t bytes_written = 0; - __u32 result = 0; int err = 0; struct packet_hash_info_t packet_info = {}; err = parse_packet(skb, &packet_info); if (err) { - return 0; + return false; } if (packet_info.is_ipv4) { @@ -521,11 +522,13 @@ static inline __u32 calculate_rss_hash(struct __sk_buff *skb, } } - if (bytes_written) { - net_toeplitz_add(&result, rss_input, bytes_written, toe); + if (!bytes_written) { + return false; } - return result; + net_toeplitz_add(result, rss_input, bytes_written, toe); + + return true; } SEC("tun_rss_steering") @@ -546,8 +549,7 @@ int tun_rss_steering_prog(struct __sk_buff *skb) return config->default_queue; } - hash = calculate_rss_hash(skb, config, toe); - if (hash) { + if (calculate_rss_hash(skb, config, toe, &hash)) { __u32 table_idx = hash % config->indirections_len; __u16 *queue = 0; -- 2.43.0