From patchwork Fri Nov 29 23:46:34 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: 18710 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 E414F83F9E for ; Sat, 30 Nov 2024 02:02:37 +0100 (CET) ARC-Seal: i=2; cv=pass; a=rsa-sha256; d=open-mesh.org; s=20121; t=1732928557; b=nsUB4aw8OSbu1Br1TNn+mD6t6BFl8S9JCN025jHZqZcbodwou+Zs+CkAqrR8n1UEVPBn0 bMG2qTbqCYUEUd5zaSqO8Vc6Pj84l6KxScNyNH+9p487qjGpLTdxST1vvPPy0oPIigSKNrV aJ5Nae34waqywJIyCFuHme/U8XK1qo8= ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=open-mesh.org; s=20121; t=1732928557; 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=UdHwjgojE8kCxHJuNd1eaBmuRo8eywf5KuF0kuOODw4=; b=gcLCti9Ybv6e1/O96yoUatwLdBYA1xDNT+TJAZtJ4q3ODujrpytb1g6uHZm/Hlt86tRXu qM9W3/kK/dSbHTgI2EbX85YDXk9EtTfeGUyAQm3O7Xez4mJ9bJwkZn5yDB5mc8zq3nIF0wa NT9lUBaBvjn1U5otBMOHr8ZHLsLtZYM= 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 36F50811B7 for ; Sat, 30 Nov 2024 01:59:49 +0100 (CET) ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=open-mesh.org; s=20121; t=1732928389; 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=UdHwjgojE8kCxHJuNd1eaBmuRo8eywf5KuF0kuOODw4=; b=pfFZbbzQI+wHewfSUZC+/hrIe3l3OCJsfqIqBNQy8cB3faHSWwf8MkInRRPVDnYkFi+g0k ezhjAMSE/49u95fbf0z2FMvqGk762KwN97I69SbCQ5uTd6IjcYgWP7SXhDQ9DQXOYIElLF uMIYVjnOyHIRqc6LBH2z0N9wudkXbdE= ARC-Seal: i=1; s=20121; d=open-mesh.org; t=1732928389; a=rsa-sha256; cv=none; b=d/NNM+2hxU0SZGn1AAb3C7rTIztyHD8xP4wyahMSiYqP14hRQlCOFn9gfAbQC0bie0zTo4 oDpJfkIVirAHqQLAiH6PEf/Zg/QkB2p81nSQCnNxbDZUvCTgZL0FTH6ZjYXwdVfGGWXaTd dNo054vPPE1A3DijjtcThiyFAx2jOnE= 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 Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id C6C4F54C71E; Sat, 30 Nov 2024 01:59:48 +0100 (CET) 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 v7 3/3] batman-adv: increase DAT DHT timeout Date: Sat, 30 Nov 2024 00:46:34 +0100 Message-ID: <20241130005942.24497-4-linus.luessing@c0d3.blue> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20241130005942.24497-1-linus.luessing@c0d3.blue> References: <20241130005942.24497-1-linus.luessing@c0d3.blue> MIME-Version: 1.0 X-Last-TLS-Session-Version: TLSv1.3 Message-ID-Hash: 24BKECX6PNTAXPI6X6MP4KEHCZSQRN4H X-Message-ID-Hash: 24BKECX6PNTAXPI6X6MP4KEHCZSQRN4H 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 b1353afb5ceb..5d548b28aa1e 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 7d0e25cef0de..f3ac3b34ef83 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) */