From patchwork Wed Sep 11 04:57:23 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Linus_L=C3=BCssing?= X-Patchwork-Id: 18664 X-Patchwork-Delegate: a@unstable.cc Return-Path: X-Original-To: patchwork@open-mesh.org Delivered-To: patchwork@open-mesh.org Received: from diktynna.open-mesh.org (localhost [IPv6:::1]) by diktynna.open-mesh.org (Postfix) with ESMTP id 19C2583EB4 for ; Wed, 11 Sep 2024 07:14:59 +0200 (CEST) ARC-Seal: i=2; cv=pass; a=rsa-sha256; d=open-mesh.org; s=20121; t=1726031699; b=mcItmnFVC5/1lMZUrly9gTRevkXhlu8G6fP7vMfXdgNpfhBY0HA5ZZ1T/EjlXGeA3i6Nw nevSBFKFG1J4KMihtqoJqLgw8+wTQhktWI9FBzAGfrhvWqiEsjzEP2lwD+2Bg4AD6fz7Uiw iKIc4tI2/GbCH2h8d+vtalSI9VFZlEM= ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=open-mesh.org; s=20121; t=1726031699; h=from : sender : reply-to : subject : date : message-id : to : cc : mime-version : content-type : content-transfer-encoding : content-id : content-description : resent-date : resent-from : resent-sender : resent-to : resent-cc : resent-message-id : in-reply-to : references : list-id : list-help : list-unsubscribe : list-subscribe : list-post : list-owner : list-archive; bh=s9pdmz+oH5pNCfsY7HYryMfy5/S5SH+pYa/hKxRSXx0=; b=t+8ubIxL22kMyFt9vmaB5RkC/kAFWLHwd/wlrrjzlc9J5ykI9aaUpZ9Vu2qfrHiOAzWwW kUsxuUfg1AeHU82NOUs/5aA2bBfGnAsNfeYVMsHlIP5c+FgkX8NA/SwlkQomzcu5bDY9f4T t3PwJAvF7jhy/iUydyHLfn1FdO83/Og= ARC-Authentication-Results: i=2; open-mesh.org; dkim=fail; arc=pass; dmarc=none Authentication-Results: open-mesh.org; dkim=fail; arc=pass; dmarc=none Received: from mail.aperture-lab.de (mail.aperture-lab.de [116.203.183.178]) by diktynna.open-mesh.org (Postfix) with ESMTPS id CD2FF83B3E for ; Wed, 11 Sep 2024 07:13:15 +0200 (CEST) ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=open-mesh.org; s=20121; t=1726031595; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=s9pdmz+oH5pNCfsY7HYryMfy5/S5SH+pYa/hKxRSXx0=; b=ZmN2CgkjdQ5ev9AaZEZCbN/yHUPCWgEBRK71MifueTeRgEVgDZ2wuRxc/7SL9o450ziKpD TzkdmYoWDpEsmzfm9v422/ru3+VXin6eaUvhlQY45WHOuYledr1a0XSz8zwlXdStpurFCN OuRiYqpg+RqeXeI22n8ZZNAvGoTDtTk= ARC-Authentication-Results: i=1; diktynna.open-mesh.org; dkim=none; spf=pass (diktynna.open-mesh.org: domain of linus.luessing@c0d3.blue designates 116.203.183.178 as permitted sender) smtp.mailfrom=linus.luessing@c0d3.blue; dmarc=none ARC-Seal: i=1; s=20121; d=open-mesh.org; t=1726031595; a=rsa-sha256; cv=none; b=x1lIlsOHJZFGIqyFSoLM+Fu2Vl0HekFvG/zWP45LIRPs3IQVVZVRHT3Zv8pwwt5qFKsUKV EgdGVmL9UWPHP6WGTUwrrXh1qHygXKxr7uCq2ZvyGd90pXYGt3YFaTJnfZsEZzaZtVlyAt sfRju/tV5s9gNfh4PIkO788iL2WtvbA= Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 29E983EEC9; Wed, 11 Sep 2024 07:13:15 +0200 (CEST) From: =?utf-8?q?Linus_L=C3=BCssing?= To: b.a.t.m.a.n@lists.open-mesh.org Cc: =?utf-8?q?Linus_L=C3=BCssing?= Subject: [PATCH v5 2/2] batman-adv: increase DAT DHT timeout Date: Wed, 11 Sep 2024 06:57:23 +0200 Message-ID: <20240911051259.23384-3-linus.luessing@c0d3.blue> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240911051259.23384-1-linus.luessing@c0d3.blue> References: <20240911051259.23384-1-linus.luessing@c0d3.blue> MIME-Version: 1.0 X-Last-TLS-Session-Version: TLSv1.3 Message-ID-Hash: EAGS7T2236X5P6LZQTNWFQCBDX4JJH4Y X-Message-ID-Hash: EAGS7T2236X5P6LZQTNWFQCBDX4JJH4Y X-MailFrom: linus.luessing@c0d3.blue X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; header-match-b.a.t.m.a.n.lists.open-mesh.org-0; header-match-b.a.t.m.a.n.lists.open-mesh.org-1; header-match-b.a.t.m.a.n.lists.open-mesh.org-2; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header X-Mailman-Version: 3.3.8 Precedence: list List-Id: The list for a Better Approach To Mobile Ad-hoc Networking Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: Currently, the DHT_GET messages of the DAT will likely be left unanswered due to the following issues: When a node has a matching DAT Cache entry for a local ARP Request then this node will answer it directly with the information provided by the cache. This however, will likely lead to missing ARP Replies from the original host. Which in turn leads to the DAT DHT not being updated. Then the local DAT cache entry will time out, triggering a unicasted DHT_GET. However, as the 5min. timeout has passed, the DAT DHT candidates will likely have purged their entry, too. So basically this results in an ARP Request broadcast fallback every five minutes. A second issue is that it is quite common that a host which has long gone offline will be tried to be contacted by another one at some remote period larger than the current 5min. timeout. This too leads to flooded ARP Requests. With this patch the purge timeout for DAT DHT entries is increased to 30min to reduce the number of DAT ARP broadcast fallbacks. Signed-off-by: Linus Lüssing --- net/batman-adv/distributed-arp-table.c | 22 +++++++++++++++++----- net/batman-adv/main.h | 3 ++- 2 files changed, 19 insertions(+), 6 deletions(-) diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index 8a054b0cf2a2..1368bba93169 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -133,15 +133,27 @@ static void batadv_dat_entry_put(struct batadv_dat_entry *dat_entry) } /** - * batadv_dat_to_purge() - check whether a dat_entry has to be purged or not + * batadv_dat_cache_to_purge() - check if a cache entry has to be purged or not * @dat_entry: the entry to check * * Return: true if the entry has to be purged now, false otherwise. */ -static bool batadv_dat_to_purge(struct batadv_dat_entry *dat_entry) +static bool batadv_dat_cache_to_purge(struct batadv_dat_entry *dat_entry) { return batadv_has_timed_out(dat_entry->last_update, - BATADV_DAT_ENTRY_TIMEOUT); + BATADV_DAT_CACHE_ENTRY_TIMEOUT); +} + +/** + * batadv_dat_dht_to_purge() - check if a DHT entry has to be purged or not + * @dat_entry: the entry to check + * + * Return: true if the entry has to be purged now, false otherwise. + */ +static bool batadv_dat_dht_to_purge(struct batadv_dat_entry *dat_entry) +{ + return batadv_has_timed_out(dat_entry->last_update, + BATADV_DAT_DHT_ENTRY_TIMEOUT); } /** @@ -202,8 +214,8 @@ static void batadv_dat_purge(struct work_struct *work) priv_dat = container_of(delayed_work, struct batadv_priv_dat, work); bat_priv = container_of(priv_dat, struct batadv_priv, dat); - __batadv_dat_purge(bat_priv->dat.cache_hash, batadv_dat_to_purge); - __batadv_dat_purge(bat_priv->dat.dht_hash, batadv_dat_to_purge); + __batadv_dat_purge(bat_priv->dat.cache_hash, batadv_dat_cache_to_purge); + __batadv_dat_purge(bat_priv->dat.dht_hash, batadv_dat_dht_to_purge); batadv_dat_start_timer(bat_priv); } diff --git a/net/batman-adv/main.h b/net/batman-adv/main.h index 97ea71a052f8..f04bce4eaf8c 100644 --- a/net/batman-adv/main.h +++ b/net/batman-adv/main.h @@ -38,7 +38,8 @@ #define BATADV_TT_WORK_PERIOD 5000 /* 5 seconds */ #define BATADV_ORIG_WORK_PERIOD 1000 /* 1 second */ #define BATADV_MCAST_WORK_PERIOD 500 /* 0.5 seconds */ -#define BATADV_DAT_ENTRY_TIMEOUT (5 * 60000) /* 5 mins in milliseconds */ +#define BATADV_DAT_CACHE_ENTRY_TIMEOUT (5 * 60000) /* 5 mins in milliseconds */ +#define BATADV_DAT_DHT_ENTRY_TIMEOUT (30 * 60000) /* 30 mins in milliseconds */ /* sliding packet range of received originator messages in sequence numbers * (should be a multiple of our word size) */