From patchwork Sat Nov 23 07:43:55 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: 18707 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 D25C084638 for ; Sat, 23 Nov 2024 08:54:26 +0100 (CET) ARC-Seal: i=2; cv=pass; a=rsa-sha256; d=open-mesh.org; s=20121; t=1732348466; b=G4cida2uPMux0cpTxmwzH/6i0+HP2MFNKyTAwDZuUDm91khYS6S5YVjaUpfTrl4V5FMQf K/k8L/fPj+GJGMVbY9EYhUprEnG+sLZ5v++waixgDtYJqv05VaSv1HdnbC/jKjRVdPMR1/s MRp5yA+CFssePLb8QOFcp1X7hSu2gbE= ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=open-mesh.org; s=20121; t=1732348466; 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=sTgp2vFPzOP+NvZZTtvCHGfwAik5xydCuI0BaGfBB8c=; b=YwQzXkHfYSmrtXNrLzj+VqJjhkffVm2OPSGK1YCUxW9N3WxBgiYnqVIsRyU7nXkJMizgf y3rGpHJW6XWQwIz4oZkyz+tIaaY5bHdSd28oF+ZnMmN/Vox8ZBC3RdSLwM7L4Qk5KJCv+ey NELPb9GPhy1WGMoN5uvTPnZqW7j7tIU= 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 97C5B83C56 for ; Sat, 23 Nov 2024 08:53:15 +0100 (CET) ARC-Seal: i=1; s=20121; d=open-mesh.org; t=1732348395; a=rsa-sha256; cv=none; b=mK/9fDc/jRvFp/FufGQPF+BQwrN10H7lDsvIzCM1csjxeWSeMfjx/5VoFDDrlMkiuzqWW7 nDhUTcu9gUQPnkFAOyc6Q/2yOfLJ8S4Y+a/Agec9DvxDAPIgI/BilGC3H0D7aBWC3rDcFu sRW/fpHBulgIwp6FH6p/S/bQ6kxwiD8= ARC-Authentication-Results: i=1; diktynna.open-mesh.org; dkim=none; dmarc=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 ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=open-mesh.org; s=20121; t=1732348395; 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=sTgp2vFPzOP+NvZZTtvCHGfwAik5xydCuI0BaGfBB8c=; b=t+RPyzhS7+X0MjyRRzTvUTkpCUenq1tfxrojix61fYm3kmd7ghNkllc0wQMdZic9mzIf7j ARdpP67aGzv+1dOCKs/Q19ktYya1DEHKonCB7590ZIfzMvVsaXRDFmAbIGSgpfLsjlc4E3 6vQSr9KSPWCpIGbq7RDtfKw5aQGf+Bk= Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 38A6954C3D5; Sat, 23 Nov 2024 08:53:15 +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 v6 2/2] batman-adv: increase DAT DHT timeout Date: Sat, 23 Nov 2024 08:43:55 +0100 Message-ID: <20241123075304.24568-3-linus.luessing@c0d3.blue> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20241123075304.24568-1-linus.luessing@c0d3.blue> References: <20241123075304.24568-1-linus.luessing@c0d3.blue> MIME-Version: 1.0 X-Last-TLS-Session-Version: TLSv1.3 Message-ID-Hash: KI34B2FOJD2EVH6N3BWPPXL5ADPNJ7II X-Message-ID-Hash: KI34B2FOJD2EVH6N3BWPPXL5ADPNJ7II 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 7f0cb0796f31..f1fa2432b90e 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) */