From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 56F2BC44515 for ; Tue, 21 Jul 2026 00:36:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Subject:Cc:To: From:Date:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=MDok9KVHR618PzvdBQVhmMe2pb6jbgGSXxiy31reXto=; b=3D2Kv2otPR2oxW93JCZzz3Hlv1 WuiSBju1OwgBAc89ucQR5SbiKBgWfZwhvKr91XkDkO4pG85s9gJknmAOf495ogs+uVXWTQYYF4oO/ 77LZ9aM4GcTcV33XsCQ0muF0HsDie9xJN/lHX20NGqP11ja383ZK6oJDErz35VmM1MNqo6MQyA/n0 FlKjaddVoIzbATgV6z2fLGYGZReCNRO89UZ0mItB9hM0NQ21aIVkUFbo3ymVHakkz+wvZHzwFhkkZ GL3qYw9eFf3HYinq9El+uO87+Dhwp5X2RXy0/dYTa6AwsLRF8VxawxF2W9cCYqMrToxJWYQcXPoue wF+QoVgw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wlySn-000000088mN-1p2P; Tue, 21 Jul 2026 00:36:01 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wlySm-000000088mC-0SJ1 for linux-arm-kernel@lists.infradead.org; Tue, 21 Jul 2026 00:36:00 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id A1C7641459; Tue, 21 Jul 2026 00:35:59 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 286641F000E9; Tue, 21 Jul 2026 00:35:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784594159; bh=MDok9KVHR618PzvdBQVhmMe2pb6jbgGSXxiy31reXto=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=nQb/sXULONrq2MhnnT3rxKO1eVgBqWrmAdNUa+6bbxrA+JzIeUWW6s9FaN8aecH6X EhBKWQf/7oJb5dqEMcC8UucfCNql494zhvwRrhDfTdgwhTqaZkSCzfFLN94Lp2Q7fh hX8wxg35rbOLNIHsQYlssOBRXVTK0R+ZAzyOpRXPHz4ymRwnTrr7cdNksj4E0qNawY hiK4yX6xzf3i5NO1l5wniO7Wo7k54PRByBsMYic9zrvNBsJalA26tek0ETjcmTbbFa L162G62ZfGJgK9clRw1ESppty99fndoezVtAVvwF3es6tkcEquLqG2Ccf0mSFgyvSo rmlJ6qxsGXr/A== Date: Mon, 20 Jul 2026 17:35:57 -0700 From: Jakub Kicinski To: Johan Alvarado Cc: andrew+netdev@lunn.ch, davem@davemloft.net, edumazet@google.com, pabeni@redhat.com, mcoquelin.stm32@gmail.com, alexandre.torgue@foss.st.com, Jose.Abreu@synopsys.com, pavel@ucw.cz, netdev@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net] net: stmmac: raise TX completion interrupt at the end of an xmit burst Message-ID: <20260720173557.09e322d7@kernel.org> In-Reply-To: <0100019f35ea26e0-42ad009c-01ab-4a8f-b126-fa65fbacae5c-000000@email.amazonses.com> References: <0100019f35ea26e0-42ad009c-01ab-4a8f-b126-fa65fbacae5c-000000@email.amazonses.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, 6 Jul 2026 05:32:45 +0000 Johan Alvarado wrote: > The TX mitigation logic only sets the Interrupt on Completion bit once > every tx_coal_frames descriptors (STMMAC_TX_FRAMES = 25), with the > tx_coal_timer hrtimer (STMMAC_COAL_TX_TIMER = 5000 us) as the only > fallback. TX skbs are freed exclusively from the TX completion path, > so any flow that keeps fewer than 25 frames in flight has all of its > skbs held for up to 5 ms after transmission. The netdev patch queue has overflown. If these patches are still relevant you'll have to repost them.