From patchwork Tue Jul 16 23:25:58 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ben Greear X-Patchwork-Id: 812966 Received: from dispatch1-us1.ppe-hosted.com (dispatch1-us1.ppe-hosted.com [148.163.129.49]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A49421DFDE for ; Tue, 16 Jul 2024 23:26:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.163.129.49 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721172369; cv=none; b=CxG+YSwS2KfkgyX4mI5GQ+EJfRYblLwnmZRkWf1BhkWCOjo+fSW4OSQCgZJGVUDoKBAFCylq6QcKOgDgNpEPBaGc7sGWRSrgVdYwIHo+ria12VuHeFlCvbM4gB2UGhPapLqZfIl93S37iPquTIHL92K0lzhZtvsPvxLJLehCjrE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721172369; c=relaxed/simple; bh=2uE8Wu5C2W+2p1m9cAhESdQKfGDHeZGIcUKAQASHK/U=; h=Message-ID:Date:MIME-Version:To:From:Subject:Content-Type; b=PWSoI0UxAOoxJ6uaxDFJlXEvO3vsy1ibSRqVmM2B7uZeRYlusDiH+tKzLxRmBHzwAHkppZ/gTXp7mFR59bNAKsCxP88R0mqeiyurfMA/wISuyRMNpXFTIOAMOAWoGiQai9bMRam0M4v5oG84TO1EwxWJLweDOURomM2jkZi+nP4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=candelatech.com; spf=pass smtp.mailfrom=candelatech.com; dkim=pass (1024-bit key) header.d=candelatech.com header.i=@candelatech.com header.b=U89F3OVN; arc=none smtp.client-ip=148.163.129.49 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=candelatech.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=candelatech.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=candelatech.com header.i=@candelatech.com header.b="U89F3OVN" X-Virus-Scanned: Proofpoint Essentials engine Received: from mail3.candelatech.com (mail.candelatech.com [208.74.158.173]) by mx1-us1.ppe-hosted.com (PPE Hosted ESMTP Server) with ESMTP id 309E3B8008D for ; Tue, 16 Jul 2024 23:25:59 +0000 (UTC) Received: from [192.168.100.159] (unknown [50.251.239.81]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail3.candelatech.com (Postfix) with ESMTPSA id A947213C2B0 for ; Tue, 16 Jul 2024 16:25:58 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 mail3.candelatech.com A947213C2B0 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=candelatech.com; s=default; t=1721172358; bh=2uE8Wu5C2W+2p1m9cAhESdQKfGDHeZGIcUKAQASHK/U=; h=Date:To:From:Subject:From; b=U89F3OVNB3cMEQVyoj96oeMkzXgQmaw7ZPlKf9Rlszon2fx+XbJ0NPuqDnVNQ2oi0 G0UtSENapMkrPIjU13D/uSXWW1U9j1mSiulMIErgFVRVl6cIVv/91YXQmQx5jFtpme m/NijfuEqme/jLdh9gx0cb4Qy00LqmGW80KlxBXA= Message-ID: Date: Tue, 16 Jul 2024 16:25:58 -0700 Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.15.1 Content-Language: en-US To: linux-wireless From: Ben Greear Subject: HACK/RFC: Fix link_sta->rx_nss == 0 in iwlwifi upon eMLSR link change. Organization: Candela Technologies X-MDID: 1721172359-mCWK-13Yhke5 X-MDID-O: us5; ut7; 1721172359; mCWK-13Yhke5; ; f7146c1849a4b08a52804beb1c1cdf45 While poking around at some instability and poor performance seen in download direction, I noticed that the rate-ctrl was probably set incorrectly in the iwlwifi driver due to link_sta->rx_nss being zero when changing active link to the secondary link (the one we didn't originally associate with). After debugging, I found that the hack below will make this problem go away. I sincerely doubt this is the correct approach, but I'm not sure how it is all supposed to work in the first place. And as a side note, even once this is fixed, download throughput still suffers much of the time. AP may be buggy, it is hard to tell where the fault lies. Thanks, Ben diff --git a/net/mac80211/rate.c b/net/mac80211/rate.c index 4dc1def69548..b69d0eb250d6 100644 --- a/net/mac80211/rate.c +++ b/net/mac80211/rate.c @@ -39,6 +39,27 @@ void rate_control_rate_init(struct sta_info *sta) ieee80211_sta_init_nss(&sta->deflink); + pr_info("rate: sta-init-nss called from rate-control-rate-init, nss: %d\n", + sta->deflink.pub->rx_nss); + + { + int z; + + for (z = 0; zlink[z], + lockdep_is_held(&local->hw.wiphy->mtx)); + if (!ls) + continue; + if (ls == &sta->deflink) + continue; + + pr_info("rate: rate-control-rate-init, setting other link rx_nss from: %d to %d link-id: %d\n", + ls->pub->rx_nss, sta->deflink.pub->rx_nss, z); + ls->pub->rx_nss = sta->deflink.pub->rx_nss; + } + } + if (!ref) return;