From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.toke.dk (mail.toke.dk [45.145.95.4]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6DB813AA1AE for ; Mon, 24 Aug 2026 10:53:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.145.95.4 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787568818; cv=none; b=aM0Fa+bMQCImVVf9ytk9s3Ll3P3MLt6pe4EHzlEraM9N8smSA3zcPfBNbywj058OVZeUsg8RjgDLkSdH0vZ2evoVJGaDHPHUrJCIaMYl91H1joLUjjav/rClJ+HQKEKuJqGq+SClNkHefZktWbFZsPH8DTVjonIizW+6ntYJPyU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787568818; c=relaxed/simple; bh=YxYqyWhF8jVUPOayUCIRYu2TYnEdqmifixKbrw4KZ+g=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=Q5f2J0ILcDmfx1f9pKBCNp+Qoxd7Zio1Lv5BhvwhTKPn2aKS9VKMWsefV8Yx769Dj1PoLwGKfp+uGT0NwVkn2W6KVH6NSL970/+5qNkWYITKQ3beDLEVeH8kGAICC8/d3+mVRrBv6lrrZUtAMS7VJ4W7AjQalg7G6uGq9d0Cseg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=toke.dk; spf=pass smtp.mailfrom=toke.dk; arc=none smtp.client-ip=45.145.95.4 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=toke.dk Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=toke.dk Authentication-Results: mail.toke.dk; dkim=none From: Toke =?utf-8?Q?H=C3=B8iland-J=C3=B8rgensen?= To: Julius Bairaktaris , Jeff Johnson Cc: linux-wireless@vger.kernel.org, ath11k@lists.infradead.org Subject: Re: [PATCH v1 4/4] wifi: ath11k: report tx airtime and enable airtime fairness In-Reply-To: <20260823195703.49198-5-julius@bairaktaris.de> References: <20260823195703.49198-1-julius@bairaktaris.de> <20260823195703.49198-5-julius@bairaktaris.de> Date: Mon, 24 Aug 2026 12:53:33 +0200 X-Clacks-Overhead: GNU Terry Pratchett Message-ID: <87se43eqmq.fsf@toke.dk> Precedence: bulk X-Mailing-List: linux-wireless@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain Julius Bairaktaris writes: > mac80211's airtime scheduler charges sta->airtime[ac].deficit from one > place, ieee80211_sta_register_airtime(). Unlike AQL there is no estimator > fallback, and ath11k never calls it, so the ATF feature bit cannot be > advertised on its own: the deficit would only ever be > replenished, every station would stay permanently in credit, and the DRR > would be inert. The bit is not a no-op in that state either, because it > also moves txq insertion to the head of the active list, which > __ieee80211_schedule_txq() documents as safe only because the DRR moves a > station back once its deficit goes negative. > > fes_duration_us arrives with every PPDU's stats and is already > accumulated into arsta->tx_duration a few lines above. Register it, and > set the feature bit in the same change so the two cannot be separated. > > Measured on an IPQ8074 AP with two stations on one radio, a 1x1 VHT > client at 433 Mbit/s and a 2x2 HE client, both receiving at once. Before, > 'iw station set airtime_weight' is refused with -EOPNOTSUPP and the > per-station airtime file reads zero. After, the weight is accepted and > read back, TX airtime accumulates, and the per-AC deficits move. > > The fairness this delivers is coarse. Weighting the fast station 4:1 moves > the slow station's share of airtime from 59.5% to 52.1% and the fast > station's throughput from 315 to 392 Mbit/s: the direction is correct, the > magnitude is not the ratio requested. How consistent is this change between runs? Seems a bit marginal if the policy was supposed to give a 4:1 ratio between stations, so does this work at all? -Toke