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=-16.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 74911C4338F for ; Mon, 9 Aug 2021 21:05:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4E6116101E for ; Mon, 9 Aug 2021 21:05:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236381AbhHIVF3 (ORCPT ); Mon, 9 Aug 2021 17:05:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:45236 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229516AbhHIVF2 (ORCPT ); Mon, 9 Aug 2021 17:05:28 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id D8A6360231; Mon, 9 Aug 2021 21:05:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1628543107; bh=M6dWNSR4WeAvv65gHUnFmzu3fgz1ckYhpeTjPCONyks=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=gT8O63BZzZZnHgl3RM1ZRwjx8bs2lBi/GdB0Ioyz0SKxzPy8KQ2qG37YSl7FrTYep PIiOTFa9vjbb3o5TO2TvlVAD6GdG7/aUDyyh0N+OYtCYbxOokcvA0QgtY95Q9Vl05P uRUVk1oOpFXdizU3XvpGBvhTbIYPFM/kWagIcsokhMC2zLYAdzQZwZoGUnbqSFNOlR ueoUZcQbHAZeoIIj26hNg8H2laqsW6V6ra3qbGGbJGgEW4iRXqnKlzi4nfQpfzb0bO g8r+goI+2pD/DL3CzuwWkxIDC7rtukfrV9x8vMiiGILEHVR5zJXvzyLdzRrO5po2Sw IcUB/K8Jv7U9A== Date: Mon, 9 Aug 2021 14:05:05 -0700 From: Jakub Kicinski To: Nicholas Richardson Cc: davem@davemloft.net, nrrichar@ncsu.edu, arunkaly@google.com, "Gustavo A. R. Silva" , Yejune Deng , Di Zhu , Ye Bin , Leesoo Ahn , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/3] pktgen: Parse internet mix (imix) input Message-ID: <20210809140505.30388445@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> In-Reply-To: <20210809172207.3890697-2-richardsonnick@google.com> References: <20210809172207.3890697-1-richardsonnick@google.com> <20210809172207.3890697-2-richardsonnick@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org 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; >