From patchwork Tue Jun 16 09:53:58 2020 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: 18117 X-Patchwork-Delegate: sw@simonwunderlich.de 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 847AE80850; Tue, 16 Jun 2020 11:54:22 +0200 (CEST) Received: from mail.aperture-lab.de (mail.aperture-lab.de [138.201.29.205]) by diktynna.open-mesh.org (Postfix) with ESMTPS id 129D2801CC for ; Tue, 16 Jun 2020 11:54:20 +0200 (CEST) From: =?utf-8?q?Linus_L=C3=BCssing?= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=c0d3.blue; s=2018; t=1592301259; 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=W1bxfH5UQtTaVLAGIdUaDW/4kYkCmlLDeCxRAozivkk=; b=XuH90fbEe7EGShZRxZU9XJgqMJa48jhv66deQK9F8C744EVdmRgMTsGSST1EPVYfhrIiXI jSOhIQeIAVEiFvQrOT/B7Ib16CQG+aHOGxWAqwkqj22vJRBb/7UHPDT1eRFu2IouHlKPjm fl2lYbBIatYjPprdRK8rGf1ih5Ifi+nai8KAsyKWtJJ686nyEJRvddY+mLJ+Ja1dsii2Zl zpLQ3T39pwzwWWARnSOjWncn/Kiq30ZXT75EIFgRPnLtfmgLTfiOyXnNKjLM8UVO6aj/qf /EgipImIGe/Iklz9leDA6Jjhn39IbOPfvwonzbycmOhUpRMoDbe4y/Zd25K+sw== To: Johannes Berg Subject: [PATCH] iw: mesh: add mesh_param "mesh_nolearn" to skip path discovery Date: Tue, 16 Jun 2020 11:53:58 +0200 Message-Id: <20200616095358.20143-2-linus.luessing@c0d3.blue> In-Reply-To: <20200616095358.20143-1-linus.luessing@c0d3.blue> References: <20200616095358.20143-1-linus.luessing@c0d3.blue> MIME-Version: 1.0 Authentication-Results: ORIGINATING; auth=pass smtp.auth=linus.luessing@c0d3.blue smtp.mailfrom=linus.luessing@c0d3.blue ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=open-mesh.org; s=20121; t=1592301260; 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:dkim-signature; bh=W1bxfH5UQtTaVLAGIdUaDW/4kYkCmlLDeCxRAozivkk=; b=3PmCbwIfie4d8q42MkQ4Jdgj638gCm4F2fCf8Z4kl6MGD7DSeziZu43Q+WIJ0doT9n2c5v WD1qyHgwOFdGfnV47NlWlPqq8iJsbPbayBM/Lao0oMNNK8eVflBbvu+jxELcQMcrwKtg6p bPoA2/ExGN3VekOq5UBN1UT+q+yrQw8= ARC-Seal: i=1; s=20121; d=open-mesh.org; t=1592301260; a=rsa-sha256; cv=none; b=aIW0bj+dAnE+nfC2SRdUVZdIRYCQ3zp/3wb9SSZN1P6780yUamsdH87AXYBT3FfcA19//F AgMl2miCfPmUScRrHY3rIEnJP5qU+sSG/lUAM3ctqs3xXRLeTC+0Tk41Htlw7+zmDOLdSD FQKHJOmaMvi0Gh0amymn/JBTD20aiiI= ARC-Authentication-Results: i=1; diktynna.open-mesh.org; dkim=none (invalid DKIM record) header.d=c0d3.blue header.s=2018 header.b=XuH90fbE; spf=none (diktynna.open-mesh.org: domain of linus.luessing@c0d3.blue has no SPF policy when checking 138.201.29.205) smtp.mailfrom=linus.luessing@c0d3.blue Message-ID-Hash: AC3ZXDGG7LGEPSEKCX4MT5MIXBLHUA6Y X-Message-ID-Hash: AC3ZXDGG7LGEPSEKCX4MT5MIXBLHUA6Y 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; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; suspicious-header CC: linux-wireless@vger.kernel.org, b.a.t.m.a.n@lists.open-mesh.org, =?utf-8?q?Linus_L=C3=BCssing?= X-Mailman-Version: 3.2.1 Precedence: list Reply-To: The list for a Better Approach To Mobile Ad-hoc Networking List-Id: The list for a Better Approach To Mobile Ad-hoc Networking Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: From: Linus Lüssing Currently, before being able to forward a packet between two 802.11s nodes, both a PLINK handshake is performed upon receiving a beacon and then later a PREQ/PREP exchange for path discovery is performed on demand upon receiving a data frame to forward. When running a mesh protocol on top of an 802.11s interface, like batman-adv, we do not need the multi-hop mesh routing capabilities of 802.11s and usually set mesh_fwding=0. However, even with mesh_fwding=0 the PREQ/PREP path discovery is still performed on demand. Even though in this scenario the next hop PREQ/PREP will determine is always the direct 11s neighbor node. The new mesh_nolearn parameter allows to skip the PREQ/PREP exchange in this scenario, leading to a reduced delay, reduced packet buffering and simplifies HWMP in general. mesh_nolearn is still rather conservative in that if the packet destination is not a direct 11s neighbor, it will fall back to PREQ/PREP path discovery. For normal, multi-hop 802.11s mesh routing it is usually not advisable to enable mesh_nolearn as a transmission to a direct but distant neighbor might be worse than reaching that same node via a more robust / higher throughput etc. multi-hop path. Cc: Sven Eckelmann Cc: Simon Wunderlich Signed-off-by: Linus Lüssing --- mesh.c | 2 ++ nl80211.h | 7 +++++++ 2 files changed, 9 insertions(+) diff --git a/mesh.c b/mesh.c index 0650d0c..48bbc3f 100644 --- a/mesh.c +++ b/mesh.c @@ -264,6 +264,8 @@ static const struct mesh_param_descr _mesh_param_descrs[] = _my_nla_put_u16, _parse_u16, _print_u16_in_TUs}, {"mesh_plink_timeout", NL80211_MESHCONF_PLINK_TIMEOUT, _my_nla_put_u32, _parse_u32, _print_u32_in_seconds}, + {"mesh_nolearn", NL80211_MESHCONF_NOLEARN, + _my_nla_put_u8, _parse_u8_as_bool, _print_u8}, }; static void print_all_mesh_param_descr(void) diff --git a/nl80211.h b/nl80211.h index c14666b..4c55e89 100644 --- a/nl80211.h +++ b/nl80211.h @@ -4228,6 +4228,12 @@ enum nl80211_mesh_power_mode { * field. If left unset then the mesh formation field will only * advertise such if there is an active root mesh path. * + * @NL80211_MESHCONF_NOLEARN: Try to avoid multi-hop path discovery (e.g. + * PREQ/PREP for HWMP) if the destination is a direct neighbor. Note that + * this might not be the optimal decision as a multi-hop route might be + * better. So if using this setting you will likely also want to disable + * dot11MeshForwarding and use another mesh routing protocol on top. + * * @__NL80211_MESHCONF_ATTR_AFTER_LAST: internal use */ enum nl80211_meshconf_params { @@ -4261,6 +4267,7 @@ enum nl80211_meshconf_params { NL80211_MESHCONF_AWAKE_WINDOW, NL80211_MESHCONF_PLINK_TIMEOUT, NL80211_MESHCONF_CONNECTED_TO_GATE, + NL80211_MESHCONF_NOLEARN, /* keep last */ __NL80211_MESHCONF_ATTR_AFTER_LAST,