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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 75F5BC43334 for ; Thu, 23 Jun 2022 13:16:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231709AbiFWNQe (ORCPT ); Thu, 23 Jun 2022 09:16:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58616 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231491AbiFWNQb (ORCPT ); Thu, 23 Jun 2022 09:16:31 -0400 Received: from mail.savoirfairelinux.com (mail.savoirfairelinux.com [208.88.110.44]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CB77B39BAE; Thu, 23 Jun 2022 06:16:29 -0700 (PDT) Received: from localhost (localhost [127.0.0.1]) by mail.savoirfairelinux.com (Postfix) with ESMTP id 3350D9C022D; Thu, 23 Jun 2022 09:16:29 -0400 (EDT) Received: from mail.savoirfairelinux.com ([127.0.0.1]) by localhost (mail.savoirfairelinux.com [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id SWXShlcTgTum; Thu, 23 Jun 2022 09:16:28 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mail.savoirfairelinux.com (Postfix) with ESMTP id 9F7769C024D; Thu, 23 Jun 2022 09:16:28 -0400 (EDT) DKIM-Filter: OpenDKIM Filter v2.10.3 mail.savoirfairelinux.com 9F7769C024D DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=savoirfairelinux.com; s=DFC430D2-D198-11EC-948E-34200CB392D2; t=1655990188; bh=lqMiz49VFoiiAzMzALh28rmRxGLLRsDC1FYZkrRivw0=; h=Date:From:To:Message-ID:MIME-Version; b=C4KqhinlFVQ5m7XVtibz4midEm8Wf1LsfZZXbz5hYnwd4dijzdt4P7Kt4R/b7EYSF njxcJgrdi87m0OZciCKhaoM4Bw23kw7VmCjSkjNiD1TpZEfnXiEAXGY736IccvuePF Trt70N2EVE6VJtXZqOpGgA0xBL/ARMVBEU21lwgPI80aU3L6oODVR0NHbGKCuDG+0E rkCTz4m1PKjiiFDgvkHpVtF1cczLR4eYlwSg8YiIwbcUREN2KkD1YODOTI3EUdDiho Ps0ufOCwWC9Bu6YomB20gnjFUKCQ2x3jfx3Ds/95ql4CIo6m7R+dYhu1SE1r3FB0Nq eYUbTeRe2CScQ== X-Virus-Scanned: amavisd-new at mail.savoirfairelinux.com Received: from mail.savoirfairelinux.com ([127.0.0.1]) by localhost (mail.savoirfairelinux.com [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id NlG6Uq43pGof; Thu, 23 Jun 2022 09:16:28 -0400 (EDT) Received: from mail.savoirfairelinux.com (mail.savoirfairelinux.com [192.168.48.237]) by mail.savoirfairelinux.com (Postfix) with ESMTP id 7C03A9C022D; Thu, 23 Jun 2022 09:16:28 -0400 (EDT) Date: Thu, 23 Jun 2022 09:16:28 -0400 (EDT) From: Enguerrand de Ribaucourt To: Andrew Lunn Cc: davem , netdev , linux-kernel , linux , hkallweit1 Message-ID: <1572348291.280163.1655990188458.JavaMail.zimbra@savoirfairelinux.com> In-Reply-To: References: <20220623085125.1426049-1-enguerrand.de-ribaucourt@savoirfairelinux.com> Subject: Re: [PATCH 1/2] net: dp83822: disable false carrier interrupt MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Mailer: Zimbra 8.8.15_GA_4272 (ZimbraWebClient - FF100 (Linux)/8.8.15_GA_4257) Thread-Topic: dp83822: disable false carrier interrupt Thread-Index: DLB6aCKOt/IFmvEdyadwXEEsBnR2Sg== Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ----- Original Message ----- > From: "Andrew Lunn" > To: "Enguerrand de Ribaucourt" > Cc: "davem" , "netdev" , "linux-kernel" , > "linux" , "hkallweit1" > Sent: Thursday, June 23, 2022 2:42:54 PM > Subject: Re: [PATCH 1/2] net: dp83822: disable false carrier interrupt > On Thu, Jun 23, 2022 at 10:51:25AM +0200, Enguerrand de Ribaucourt wrote: > > When unplugging an Ethernet cable, false carrier events were produced by > > the PHY at a very high rate. Once the false carrier counter full, an > > interrupt was triggered every few clock cycles until the cable was > > replugged. This resulted in approximately 10k/s interrupts. > > Since the false carrier counter (FCSCR) is never used, we can safely > > disable this interrupt. > > In addition to improving performance, this also solved MDIO read > > timeouts I was randomly encountering with an i.MX8 fec MAC because of > > the interrupt flood. The interrupt count and MDIO timeout fix were > > tested on a v5.4.110 kernel. > Since this is version 2, you should add v2 into the subject line. See > the submitting patches document in the kernel documentation. > Also, with patch sets, please include a patch 0/X which describes the > big picture. > This is also a bug fix, you are stopping an interrupt storm. So please > include a Fixes: tag indicating where the issue was introduced. > The code itself looks good, it is just getting the processes right. > Andrew Sorry, I'm still not familiar with the process. I resubmitted the patches with your recommendations. Thank you very much for your advice. Enguerrand