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=-23.3 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_IN_DEF_DKIM_WL autolearn=unavailable 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 094A4C4338F for ; Thu, 12 Aug 2021 18:12:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C5A1160F91 for ; Thu, 12 Aug 2021 18:12:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237501AbhHLSNS (ORCPT ); Thu, 12 Aug 2021 14:13:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44076 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229508AbhHLSNR (ORCPT ); Thu, 12 Aug 2021 14:13:17 -0400 Received: from mail-lj1-x236.google.com (mail-lj1-x236.google.com [IPv6:2a00:1450:4864:20::236]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 18E1BC061756 for ; Thu, 12 Aug 2021 11:12:52 -0700 (PDT) Received: by mail-lj1-x236.google.com with SMTP id u13so11813461lje.5 for ; Thu, 12 Aug 2021 11:12:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=3IBmrG9EcDzssiR9dY8YvqnK3/P6vQnXnwNHy7NXG/k=; b=PlfAVLvuNc6jHEPbPFgM44WkQ88pFCwSTly6DaMvO6LslArYLa2GXaxCOLdDQCvoRR oqnnON+xFf8WVTINtLj9fl2ez+E2jHjru57cMVZdicymTW/pXF+lzSr80TmaP2xi3Ldc GJBLnMqM/hBw5kmRFdzgG92f+EoOQ/f6StlfQ2pQyA1nai6B+kiKBmDO9D6qBGBuOU+5 8OZNsWirzY7N6CQ1UJjW1kJypmfPITQkJU6BS9/p0KHNF7pr9OsP/V8mKGHblbJVWFk+ 9TPQGuZiKzKkBYVreW4RHw8Q3j1RJngjJsRVtC6H3c1PFl5n8QLPpmm6oZdStlh7dp8f U3kw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=3IBmrG9EcDzssiR9dY8YvqnK3/P6vQnXnwNHy7NXG/k=; b=gcRJWRuGx7vVstYkV5cEHtn+xCM3V5y4kYq5yJ6uVTE2U9HKtUe7X5daYocNwyDsii KUIOUwoJ7t1x5ilQFpMTGSe05wEv4xsZIRDWX1VdgNOCGlNlzzjbE6kDpzR2m1a0ofQS QdHqGL2HC3Y/ielSsaIFa7GsgVlx8lW+Hm+UWA0aFkfu/4wAj0elliY014pC9SeTXpPK gBLSW78OxxD2fHy70KxOrl+m5VKZX8ajN2aM+Cd58MfCpOH2OtKMhj51/+c2HaQc50FB iOgKDSpC2+sTgPCJt8kDGwHNaMT/yxVVoPhDEjfhLRKZlLY1/iS+fRnaxfMyVGhmd141 W5EA== X-Gm-Message-State: AOAM530g7PCcXqlEYQ0A1lTbx1FdYLI7056KHInOvJhDXaBRy5ntl1iN mUvyTUra2x5NLLEg9nFDSzme4M4nNSprR37vFkT2FA== X-Google-Smtp-Source: ABdhPJwNIbPyauYgPanl0IavUisSfmfdQnkFz6j64zcXJ2xb6P6xRGL05iZxUjPfhmk91DMZ52lczsPQKghAqZCCCrU= X-Received: by 2002:a2e:b0d1:: with SMTP id g17mr3914413ljl.153.1628791969964; Thu, 12 Aug 2021 11:12:49 -0700 (PDT) MIME-Version: 1.0 References: <20210809172207.3890697-1-richardsonnick@google.com> <20210809172207.3890697-2-richardsonnick@google.com> <20210809140505.30388445@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> In-Reply-To: <20210809140505.30388445@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> From: Nick Richardson Date: Thu, 12 Aug 2021 14:12:38 -0400 Message-ID: Subject: Re: [PATCH 1/3] pktgen: Parse internet mix (imix) input To: Jakub Kicinski Cc: davem@davemloft.net, nrrichar@ncsu.edu, Arun Kalyanasundaram , "Gustavo A. R. Silva" , Yejune Deng , Di Zhu , Ye Bin , Leesoo Ahn , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Philip Romanov Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Hey Jakub, thanks for the quick response! > > + > > + len = num_arg(&buffer[i], max_digits, &size); > > + if (len < 0) > > + return len; > > + i += len; > > + if (get_user(c, &buffer[i])) > > + return -EFAULT; > > + /* Check for comma between size_i and weight_i */ > > + if (c != ',') > > + return -EINVAL; > > + i++; > > + > > + if (size < 14 + 20 + 8) > > + size = 14 + 20 + 8; > > Why overwrite instead of rejecting? I overwrite here to keep behavior similar to when pkt_size is set directly. When the pkt_size command is used the size value is overwritten to the minimum packet size (14 + 8 + 20). See the pkt_size section in pktgen_if_write(). > > > + len = num_arg(&buffer[i], max_digits, &weight); > > + if (len < 0) > > + return len; > > + if (weight <= 0) > > + return -EINVAL; > > + > > + pkt_dev->imix_entries[pkt_dev->n_imix_entries].size = size; > > + pkt_dev->imix_entries[pkt_dev->n_imix_entries].weight = weight; > > + > > + i += len; > > + if (get_user(c, &buffer[i])) > > + return -EFAULT; > > What if this is the last entry? If this is the last entry then the line terminating character is read. Similar code can be found in the get_labels() function in pktgen.c On Mon, Aug 9, 2021 at 5:05 PM Jakub Kicinski wrote: > > On Mon, 9 Aug 2021 17:22:02 +0000 Nicholas Richardson wrote: > > From: Nick Richardson > > > > Adds "imix_weights" command for specifying internet mix distribution. > > > > The command is in this format: > > "imix_weights size_1,weight_1 size_2,weight_2 ... size_n,weight_n" > > where the probability that packet size_i is picked is: > > weight_i / (weight_1 + weight_2 + .. + weight_n) > > > > The user may provide up to 20 imix entries (size_i,weight_i) in this > > command. > > > > The user specified imix entries will be displayed in the "Params" > > section of the interface output. > > > > Values for clone_skb > 0 is not supported in IMIX mode. > > > > Summary of changes: > > Add flag for enabling internet mix mode. > > Add command (imix_weights) for internet mix input. > > Return -ENOTSUPP when clone_skb > 0 in IMIX mode. > > Display imix_weights in Params. > > Create data structures to store imix entries and distribution. > > > > Signed-off-by: Nick Richardson > > --- > > net/core/pktgen.c | 95 +++++++++++++++++++++++++++++++++++++++++++++++ > > 1 file changed, 95 insertions(+) > > > > diff --git a/net/core/pktgen.c b/net/core/pktgen.c > > index 7e258d255e90..83c83e1b5f28 100644 > > --- a/net/core/pktgen.c > > +++ b/net/core/pktgen.c > > @@ -175,6 +175,8 @@ > > #define IP_NAME_SZ 32 > > #define MAX_MPLS_LABELS 16 /* This is the max label stack depth */ > > #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 func_enter() pr_debug("entering %s\n", __func__); > > > > @@ -242,6 +244,12 @@ static char *pkt_flag_names[] = { > > #define VLAN_TAG_SIZE(x) ((x)->vlan_id == 0xffff ? 0 : 4) > > #define SVLAN_TAG_SIZE(x) ((x)->svlan_id == 0xffff ? 0 : 4) > > > > +struct imix_pkt { > > + __u64 size; > > + __u64 weight; > > + __u64 count_so_far; > > no need for the __ prefix outside of uAPI. > > > +}; > > + > > struct flow_state { > > __be32 cur_daddr; > > int count; > > @@ -343,6 +351,10 @@ struct pktgen_dev { > > __u8 traffic_class; /* ditto for the (former) Traffic Class in IPv6 > > (see RFC 3260, sec. 4) */ > > > > + /* IMIX */ > > + unsigned int n_imix_entries; > > + struct imix_pkt imix_entries[MAX_IMIX_ENTRIES]; > > + > > /* MPLS */ > > unsigned int nr_labels; /* Depth of stack, 0 = no MPLS */ > > __be32 labels[MAX_MPLS_LABELS]; > > @@ -552,6 +564,16 @@ static int pktgen_if_show(struct seq_file *seq, void *v) > > (unsigned long long)pkt_dev->count, pkt_dev->min_pkt_size, > > pkt_dev->max_pkt_size); > > > > + if (pkt_dev->n_imix_entries > 0) { > > + seq_printf(seq, " imix_weights: "); > > + for (i = 0; i < pkt_dev->n_imix_entries; i++) { > > + seq_printf(seq, "%llu,%llu ", > > + pkt_dev->imix_entries[i].size, > > + pkt_dev->imix_entries[i].weight); > > + } > > + seq_printf(seq, "\n"); > > seq_puts() > > > + } > > + > > seq_printf(seq, > > " frags: %d delay: %llu clone_skb: %d ifname: %s\n", > > pkt_dev->nfrags, (unsigned long long) pkt_dev->delay, > > @@ -792,6 +814,61 @@ static int strn_len(const char __user * user_buffer, unsigned int maxlen) > > return i; > > } > > > > +static ssize_t get_imix_entries(const char __user *buffer, > > + struct pktgen_dev *pkt_dev) > > +{ > > + /* Parses imix entries from user buffer. > > + * The user buffer should consist of imix entries separated by spaces > > + * where each entry consists of size and weight delimited by commas. > > + * "size1,weight_1 size2,weight_2 ... size_n,weight_n" for example. > > + */ > > This comments belongs before the function. > > > + long len; > > + char c; > > + int i = 0; > > + const int max_digits = 10; > > Please order these lines longest to shortest (reverse xmas tree). > > > + pkt_dev->n_imix_entries = 0; > > + > > + do { > > + unsigned long size; > > + unsigned long weight; > > same > > > + > > + len = num_arg(&buffer[i], max_digits, &size); > > + if (len < 0) > > + return len; > > + i += len; > > + if (get_user(c, &buffer[i])) > > + return -EFAULT; > > + /* Check for comma between size_i and weight_i */ > > + if (c != ',') > > + return -EINVAL; > > + i++; > > + > > + if (size < 14 + 20 + 8) > > + size = 14 + 20 + 8; > > Why overwrite instead of rejecting? > > > + len = num_arg(&buffer[i], max_digits, &weight); > > + if (len < 0) > > + return len; > > + if (weight <= 0) > > + return -EINVAL; > > + > > + pkt_dev->imix_entries[pkt_dev->n_imix_entries].size = size; > > + pkt_dev->imix_entries[pkt_dev->n_imix_entries].weight = weight; > > + > > + i += len; > > + if (get_user(c, &buffer[i])) > > + return -EFAULT; > > What if this is the last entry? > > > + i++; > > + pkt_dev->n_imix_entries++; > > + > > + if (pkt_dev->n_imix_entries > MAX_IMIX_ENTRIES) > > + return -E2BIG; > > + } while (c == ' '); > > empty line here > > > + return i; > > +} > > + > > static ssize_t get_labels(const char __user *buffer, struct pktgen_dev *pkt_dev) > > { > > unsigned int n = 0; > > @@ -960,6 +1037,18 @@ static ssize_t pktgen_if_write(struct file *file, > > return count; > > } > > > > + if (!strcmp(name, "imix_weights")) { > > + if (pkt_dev->clone_skb > 0) > > + return -ENOTSUPP; > > ENOTSUPP should not be returned to user space, please use a different > one. > > > + len = get_imix_entries(&user_buffer[i], pkt_dev); > > + if (len < 0) > > + return len; > > + > > + i += len; > > + return count; > > + } > > + > > if (!strcmp(name, "debug")) { > > len = num_arg(&user_buffer[i], 10, &value); > > if (len < 0) > > @@ -1082,10 +1171,16 @@ static ssize_t pktgen_if_write(struct file *file, > > len = num_arg(&user_buffer[i], 10, &value); > > if (len < 0) > > return len; > > + /* clone_skb is not supported for netif_receive xmit_mode and > > + * IMIX mode. > > + */ > > if ((value > 0) && > > ((pkt_dev->xmit_mode == M_NETIF_RECEIVE) || > > !(pkt_dev->odev->priv_flags & IFF_TX_SKB_SHARING))) > > return -ENOTSUPP; > > + if (value > 0 && pkt_dev->n_imix_entries > 0) > > + return -ENOTSUPP; > > ditto > > > i += len; > > pkt_dev->clone_skb = value; > > > -- Nick Richardson (he/him/his) SWE Intern 1 (919) 410 3510 careers.google.com/students |Learn more about our candidate privacy policy.|