From patchwork Mon Aug 9 17:22:03 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicholas Richardson X-Patchwork-Id: 494857 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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 95B21C4338F for ; Mon, 9 Aug 2021 17:23:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 732C561058 for ; Mon, 9 Aug 2021 17:23:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234319AbhHIRXW (ORCPT ); Mon, 9 Aug 2021 13:23:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56934 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234210AbhHIRXT (ORCPT ); Mon, 9 Aug 2021 13:23:19 -0400 Received: from mail-qv1-xf49.google.com (mail-qv1-xf49.google.com [IPv6:2607:f8b0:4864:20::f49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BB2A5C0613D3 for ; Mon, 9 Aug 2021 10:22:58 -0700 (PDT) Received: by mail-qv1-xf49.google.com with SMTP id f10-20020a0ccc8a0000b02903521ac3b9d7so4042938qvl.15 for ; Mon, 09 Aug 2021 10:22:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=zob3UxBCZJOXL7+Saz9eyr6rn9i6ZG0QqW2KutXmaCw=; b=CZfapeTkzBQt16ltomwZpYcT1FjIsPBszmbvmk6E0Fz7l1iuDe1kNfCBZFgyoSFO+A N9xZ9quGmXNLxaHteHL/h37VRrcrQQvpSpEUWVbg6vl3CKTRVDxQzLPWgg4ll1iB5wT6 k5Tj3qL3CrNL60KAeS+1MtbgmZ0bhhvWGrIms7E1hmB6m+f6neI6xkKLXgbcBRfiWimP 2FUQBI0YlBwaa3bp6K8FsvfkeVuoeXlR7gua6xkpsziIhepesjrlc5IXt/B4IsdXBMYd wDbMeN3Tm+ehCVkb0NJbKe1xcSGwcyrzun7dOroGyiBDMgb/+IC3/J4HnXZVCXVoW3lo RJBw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=zob3UxBCZJOXL7+Saz9eyr6rn9i6ZG0QqW2KutXmaCw=; b=CQ0nNcW+wy5GDdAq9ce2mnXhAZI70GwTiLGVC5q4dmBuL++4WTPnpoc1k/BHDPwbK8 s3BtJApFKrP4xy2ZJ+FfdtYcLzDErxI6Mc1iOI0Tw3Dml4lcHyKNK68bA3e47Fe/hwdR xtvQooTgzmfR9crVZqt6fYtXr13CdLSYb4cH8m/Q3rrvkGnLacghi3ChQO1uF5okj1NC Ctyg0OM69reLQ363jcCWINY1saMnNfoNmzePx0/GPtV6aHnf+c8FQRT6ehedzeCpQ9en ez9k5hNWOAtAxZ15GR+ym70jlY5yeELm/xI2sn6Xhd02vpRIrRK2K/HshMWttFRaQsoO IXJQ== X-Gm-Message-State: AOAM532fhMoJsatOWOGf6LzuWJQ95ib46R5K9BLFhguIARTpxB3O/JS4 mS0luf+Mx6Y2LO8rSwmP7QqHvEyUafyrbL4YQ4jC8A== X-Google-Smtp-Source: ABdhPJxXLB/5bgROHElsTEKC1vPGaTBNAh2SbwYNIKQjRon/lN1p5FM1mh7wpJeDitwnaIhwEJoiTwxWc9Axtf5bFmKMDA== X-Received: from mustash.c.googlers.com ([fda3:e722:ac3:cc00:14:4d90:c0a8:337b]) (user=richardsonnick job=sendgmr) by 2002:a05:6214:9d2:: with SMTP id dp18mr13523234qvb.46.1628529777974; Mon, 09 Aug 2021 10:22:57 -0700 (PDT) Date: Mon, 9 Aug 2021 17:22:03 +0000 In-Reply-To: <20210809172207.3890697-1-richardsonnick@google.com> Message-Id: <20210809172207.3890697-3-richardsonnick@google.com> Mime-Version: 1.0 References: <20210809172207.3890697-1-richardsonnick@google.com> X-Mailer: git-send-email 2.32.0.605.g8dce9f2422-goog Subject: [PATCH 2/3] pktgen: Add imix distribution bins From: Nicholas Richardson To: davem@davemloft.net, kuba@kernel.org Cc: nrrichar@ncsu.edu, arunkaly@google.com, Nick Richardson , "Gustavo A. R. Silva" , Leesoo Ahn , Di Zhu , Ye Bin , Yejune Deng , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Nick Richardson In order to represent the distribution of imix packet sizes, a pre-computed data structure is used. It features 100 (IMIX_PRECISION) "bins". Contiguous ranges of these bins represent the respective packet size of each imix entry. This is done to avoid the overhead of selecting the correct imix packet size based on the corresponding weights. Example: imix_weights 40,7 576,4 1500,1 total_weight = 7 + 4 + 1 = 12 pkt_size 40 occurs 7/total_weight = 58% of the time pkt_size 576 occurs 4/total_weight = 33% of the time pkt_size 1500 occurs 1/total_weight = 9% of the time We generate a random number between [0-99] and select the corresponding packet size based on the specified weights. Eg. random number = 358723895 % 100 = 65 Selects the packet size corresponding to index:65 in the pre-computed imix_distribution array. An example of the pre-computed array is below: The imix_distribution will look like the following: 0 -> 0 (index of imix_entry.size == 40) 1 -> 0 (index of imix_entry.size == 40) 2 -> 0 (index of imix_entry.size == 40) [...] -> 0 (index of imix_entry.size == 40) 57 -> 0 (index of imix_entry.size == 40) 58 -> 1 (index of imix_entry.size == 576) [...] -> 1 (index of imix_entry.size == 576) 90 -> 1 (index of imix_entry.size == 576) 91 -> 2 (index of imix_entry.size == 1500) [...] -> 2 (index of imix_entry.size == 1500) 99 -> 2 (index of imix_entry.size == 1500) Create and use "bin" representation of the imix distribution. Signed-off-by: Nick Richardson --- net/core/pktgen.c | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) diff --git a/net/core/pktgen.c b/net/core/pktgen.c index 83c83e1b5f28..be46de1d6eec 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -177,6 +177,7 @@ #define MPLS_STACK_BOTTOM htonl(0x00000100) /* Max number of internet mix entries that can be specified in imix_weights. */ #define MAX_IMIX_ENTRIES 20 +#define IMIX_PRECISION 100 /* Precision of IMIX distribution */ #define func_enter() pr_debug("entering %s\n", __func__); @@ -354,6 +355,8 @@ struct pktgen_dev { /* IMIX */ unsigned int n_imix_entries; struct imix_pkt imix_entries[MAX_IMIX_ENTRIES]; + /* Maps 0-IMIX_PRECISION range to imix_entry based on probability*/ + __u8 imix_distribution[IMIX_PRECISION]; /* MPLS */ unsigned int nr_labels; /* Depth of stack, 0 = no MPLS */ @@ -483,6 +486,7 @@ static void pktgen_stop_all_threads(struct pktgen_net *pn); static void pktgen_stop(struct pktgen_thread *t); static void pktgen_clear_counters(struct pktgen_dev *pkt_dev); +static void fill_imix_distribution(struct pktgen_dev *pkt_dev); /* Module parameters, defaults. */ static int pg_count_d __read_mostly = 1000; @@ -1045,6 +1049,8 @@ static ssize_t pktgen_if_write(struct file *file, if (len < 0) return len; + fill_imix_distribution(pkt_dev); + i += len; return count; } @@ -2572,6 +2578,14 @@ static void mod_cur_headers(struct pktgen_dev *pkt_dev) t = pkt_dev->min_pkt_size; } pkt_dev->cur_pkt_size = t; + } else if (pkt_dev->n_imix_entries > 0) { + struct imix_pkt *entry; + __u32 t = prandom_u32() % IMIX_PRECISION; + __u8 entry_index = pkt_dev->imix_distribution[t]; + + entry = &pkt_dev->imix_entries[entry_index]; + entry->count_so_far++; + pkt_dev->cur_pkt_size = entry->size; } set_cur_queue_map(pkt_dev); @@ -2640,6 +2654,33 @@ static void free_SAs(struct pktgen_dev *pkt_dev) } } +static void fill_imix_distribution(struct pktgen_dev *pkt_dev) +{ + int cumulative_probabilites[MAX_IMIX_ENTRIES]; + int j = 0; + __u64 cumulative_prob = 0; + __u64 total_weight = 0; + int i = 0; + + for (i = 0; i < pkt_dev->n_imix_entries; i++) + total_weight += pkt_dev->imix_entries[i].weight; + + /* Fill cumulative_probabilites with sum of normalized probabilities */ + for (i = 0; i < pkt_dev->n_imix_entries - 1; i++) { + cumulative_prob += div64_u64(pkt_dev->imix_entries[i].weight * + IMIX_PRECISION, + total_weight); + cumulative_probabilites[i] = cumulative_prob; + } + cumulative_probabilites[pkt_dev->n_imix_entries - 1] = 100; + + for (i = 0; i < IMIX_PRECISION; i++) { + if (i == cumulative_probabilites[j]) + j++; + pkt_dev->imix_distribution[i] = j; + } +} + static int process_ipsec(struct pktgen_dev *pkt_dev, struct sk_buff *skb, __be16 protocol) {