From patchwork Tue Aug 17 23:51:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nicholas Richardson X-Patchwork-Id: 499624 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 6355BC4338F for ; Tue, 17 Aug 2021 23:51:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4487360F39 for ; Tue, 17 Aug 2021 23:51:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236814AbhHQXw3 (ORCPT ); Tue, 17 Aug 2021 19:52:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44440 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236787AbhHQXw2 (ORCPT ); Tue, 17 Aug 2021 19:52:28 -0400 Received: from mail-vs1-xe49.google.com (mail-vs1-xe49.google.com [IPv6:2607:f8b0:4864:20::e49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E90BBC0617AF for ; Tue, 17 Aug 2021 16:51:53 -0700 (PDT) Received: by mail-vs1-xe49.google.com with SMTP id a186-20020a671ac30000b0290289c309d3b2so199545vsa.18 for ; Tue, 17 Aug 2021 16:51:53 -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=k3/pK0CBn1A5G7wmRtLTVqgpdu0r/GTbQhPeFcXxvFY=; b=ezCUgRcS7hbHqYdcKEr0XSHh+C2g/EVQSoS+dFXfsQKC64yA6NqxjFkKItwWO38uTV ncg15u+8n6C9kxFndEqdo+y/ngDMPaQHUeX+SZ9lAsM8d60DcGfPhy3HStG0hLMnnfXq TQsKr+Zv5Tdvu+gNjoBahmERLn2B63skVaLAPqCps7UZ40KngExg60kCO67gJCkU8JXj FH/xn33919O6rUD2kl2KlQpao9ht9L+ZKuZMsLdtcMuZ5C2E+EsYD957mZqjiex5I5lI +DOpiOPhaHvJBkkH1OsUjD7zbUFSO3g4lfOsG3tzwfhWLaazNVm6utpPInfscLfuKdGy EQlQ== 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=k3/pK0CBn1A5G7wmRtLTVqgpdu0r/GTbQhPeFcXxvFY=; b=rsFG5lsPK9iOqyaFsKFzoV6msZhiQzJfqpNKobDwPGTWIEOan/kjbiFSvRnvFl+WKr WbY9bWdaO46JZ9IK5VEFoPu2iWi5KHeW820WOkE4Tev1OpN1VGjt0opHnWuzfNvA9vQ7 xmV5cSI09u1HdYC+l0z6G9VlJg+11J/JwT7TPCmLPXowNN42QLCpf2jV9uf8if6bf82w 5QJyiJL8Nm6fBIisIdk/s3ji1AfGzQX0cNrCIhZkvjVYJAhQQVfKs18HCkeZqszZpOs/ JujserQzz2yvSbsixeYyOiVVrNwG3YUGwiTF+P+XC9+lCXzzpetaJwHwvD/pTXkfZnuh 1btA== X-Gm-Message-State: AOAM530v6WRUnwT/rwn5wq91T9FmUlWDUGx/Oi8UoIxlteUmttZuWtWf ai/XNujQiH+28lg7rJbS5mBk8LSHW8KyuXF5a+q5gqGJc5LqeMPMx3kbnFGhOjnSwxVIpQSLJIF babz3pMKBLnRTK5yslmG4ftUX+0CZaRiLrDGf4Q5CJyxmx1HkpS3iA+TVqtK/Y4FWY5BJKwNnee NQ5I5H3zo= X-Google-Smtp-Source: ABdhPJzLRv1JuVVLa9pCsI3wSB+ZLbyYwnSYcTz35ZEQSZ5fitRriUlcdld3rPgAndZCZWnWNXZ7POBq8Sbb3KdQ8rB51A== X-Received: from mustash.c.googlers.com ([fda3:e722:ac3:cc00:14:4d90:c0a8:337b]) (user=richardsonnick job=sendgmr) by 2002:a05:6102:3f50:: with SMTP id l16mr5638742vsv.10.1629244312829; Tue, 17 Aug 2021 16:51:52 -0700 (PDT) Date: Tue, 17 Aug 2021 23:51:37 +0000 In-Reply-To: <20210817235141.1136355-1-richardsonnick@google.com> Message-Id: <20210817235141.1136355-3-richardsonnick@google.com> Mime-Version: 1.0 References: <20210817235141.1136355-1-richardsonnick@google.com> X-Mailer: git-send-email 2.33.0.rc1.237.g0d66db33f3-goog Subject: [PATCH v3 2/3] pktgen: Add imix distribution bins From: Nicholas Richardson To: netdev@vger.kernel.org, davem@davemloft.net, kuba@kernel.org Cc: nrrichar@ncsu.edu, promanov@google.com, arunkaly@google.com, Nick Richardson , "Gustavo A. R. Silva" , Ye Bin , Leesoo Ahn , Yejune Deng , Di Zhu , 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 0-100 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 | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/net/core/pktgen.c b/net/core/pktgen.c index a7e45eaccef7..9e78edf0f69b 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; @@ -1046,6 +1050,8 @@ static ssize_t pktgen_if_write(struct file *file, if (len < 0) return len; + fill_imix_distribution(pkt_dev); + i += len; return count; } @@ -2573,6 +2579,14 @@ 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); @@ -2580,6 +2594,32 @@ static void mod_cur_headers(struct pktgen_dev *pkt_dev) pkt_dev->flows[flow].count++; } +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; + } +} #ifdef CONFIG_XFRM static u32 pktgen_dst_metrics[RTAX_MAX + 1] = {