From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=185.246.84.56 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793732190; b=Kyk2hsN+oY3Cz+pCbwFIg8UcLV7pwFaG/Tk9SBh2KBYM1GyEDV//cyb+yb+4h27+9WwT JIaZUD74H50h7s+LBIQEqWyt1VBZ7r0XPkJG/xS4Q/t6FyUHYMalbu2BkLO6uZwc2hhUr VJrW4Wk3DKgifBXvYLgPdmDiIaKLK7adJZzNIBKqkyN141JOIeI6tPioCWAJY24qr2buG wZOnQByq09tQ8da8MLPNqfuSA2OM6dA4XX4yvqzpIjAtGoiD3RHGoadK+XtZXWnrPdE64 f/3mKPZjAUGxzzkaIrY6pAUUl/Mcupwj5LdfT7QZYXaak4Mxh0KqXZnlgdrX50KW63A== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793732190; h=DMARC-Filter:Received:Received:Received:DKIM-Signature:Message-ID: Date:MIME-Version:User-Agent:Subject:To:Cc:References: Content-Language:From:In-Reply-To:Content-Type: Content-Transfer-Encoding:X-Last-TLS-Session-Version; bh=5629z1hliFgRB1i8Gc9oK4Mr2yUaR1BiwYHKsmR/8Bs=; b=vHRbnmgg1wiogPXRK31msNKQTOVnQJLcbR6yLd/+Mj8B8NMSWN9BPc21mrJhzuedkVFU MdvNdTeM0YNPmEbaOhYyPK821e55LP/q2aHwSKwCHFWtyEWCLGlJ5rnDGfe4cyosBlm0R h2CiqygNBaygbQ4dn6s62qqf71BMT2BbFjkQFNxT8EpFVbW+3eqsI6PpMRQgFca53t/Gj OpeglA2KDlzEWE5BcpnbNsCp50xfvAbRedFe51X4SrTVsaX22T44oJHmVkgMsFmnhJuXK XFxu0WeSBsAu2mVxu/wfz3HSyQuzh6iPvrcx+iJnpYoHHpm2vkZbujDjaZt+9UbijRQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass header.d=bootlin.com header.i=@bootlin.com header.a=rsa-sha256 header.s=dkim header.b=miTVynxt; arc=none smtp.remote-ip=185.246.84.56 Received: from smtpout-02.galae.net (smtpout-02.galae.net [185.246.84.56]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B659D606A326 for ; Tue, 3 Nov 2026 18:56:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org B659D606A326 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=bootlin.com header.i=@bootlin.com header.a=rsa-sha256 header.s=dkim header.b=miTVynxt Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-02.galae.net (Postfix) with ESMTPS id 1DD001A143C; Tue, 3 Nov 2026 18:56:27 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id DE3386046C; Tue, 3 Nov 2026 18:56:26 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 95D44103291F9; Tue, 3 Nov 2026 19:56:21 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1793732186; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:content-language:in-reply-to:references; bh=5629z1hliFgRB1i8Gc9oK4Mr2yUaR1BiwYHKsmR/8Bs=; b=miTVynxtoXW9Wx5uPS4QgDE1vcHvI5QwANZ+tG+FRuGk4H8WHeC7aTpwlSmpDUuz8SsLJ0 LUEq9DxhZzFInjwaVRy2udvRdr0Y8swZGhaxanz6tCGB/2pIzER0lx1fcNVPdGtlDeu7iS k/p2Dw+A9xnuTa9vegqSHSQ0Sx+F1YlKP5uIbxjEL+MTJXo+7GddtcNQ1yCyvFVYCQyv1h sN+u6TKnIe8boAweKC1PZNC1f8dxVpZ8pJLw/tE63Spjhv6uPgYHU3wIyDPGeh+uo1SsR7 YigMHQkG7EFROpBjfJruu/ffYaGjWfNdt2nXhwRu2L7pMvtUlQiY9JPf0/6XXg== Message-ID: <862976ab-e80e-4d6b-9657-ad9bba2d020b@bootlin.com> Date: Tue, 3 Nov 2026 19:56:20 +0100 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH net v2 0/5] net: mvneta: fix the TX queue arbitration and the mqprio offload To: Josef Schlehofer , netdev@vger.kernel.org Cc: marcin.s.wojtas@gmail.com, andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@kernel.org, kuba@kernel.org, pabeni@redhat.com, w@1wt.eu, linux-kernel@vger.kernel.org References: <20261103125021.70845-1-pepe.schlehofer@gmail.com> Content-Language: en-US From: Maxime Chevallier In-Reply-To: <20261103125021.70845-1-pepe.schlehofer@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Last-TLS-Session-Version: TLSv1.3 Hi Josef, On 11/3/26 13:50, Josef Schlehofer wrote: > The NETA TX arbiter is left at its reset default, which serves the TX > queues in fixed priority. Under load a busy queue starves the others. > OpenWrt has worked around this since 2017 by sending all TX traffic > of its 32-bit boards through queue 0 [1]. > > Patch 3 serves the queues in weighted round robin. While working on it, > four older bugs in the mqprio offload showed up. Turning the shaper off > leaves the per-queue rate limits in place (patch 1). Deleting the qdisc > never reaches the driver (patch 2). A failed setup is not undone > (patch 4). Opening the interface or changing its MTU sets every rate > limit to 10.23 Mbit/s (patch 5). > > The series was tested on a Turris Omnia (Armada 385). The other NETA > variants were not tested, but the driver already programs registers of > the same block (MVNETA_TX_MTU and the token sizes) on all of them. > Suspend and resume were not tested. > > With patch 2, replacing an offloaded mqprio qdisc with another mqprio > under a new handle loses the new configuration. The new qdisc is set up > before the old one is torn down, and the driver now acts on that > teardown. Software mqprio loses the configuration in the same way. Wouldn't this break mqprio offload ? It's no longer priorising then ? That behaviour of the high-prio queue potentially starving the other is likely what mqprio users actually need, so maybe we need to setup prio-based queue selection when adding an mqprio qdisc, and switch back to WRR when its removed ? Maxime