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 X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 925D6C4727C for ; Thu, 1 Oct 2020 13:58:07 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2BC3720872 for ; Thu, 1 Oct 2020 13:58:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="0cz+M/RC"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="MXeH6FmI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2BC3720872 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject: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=BlFXDqK5qZJhbEXo9a6+vufZHWGbh6/SHcfSw/2C9bs=; b=0cz+M/RCbQdhw4DdwK/o9Kr9o w4Vbeif0rSmFkAT8bpDeRC7k8pKUPv4IsHLMJ/6yaXkbBB+9tzMpQfxx6VxiyLLke2o9MSuvk4BZl TZnYSOXeWqJroEtLFW2xoygbJ+gGgin2whaYjq5WiHjWQ9w+6pAnDzkU2iylMFz8F4pN5dqt910SZ uOuW6V+oDtDhsZ8uSihksjwSf5WH07r/cvMl8tCgv+s8edgExhaw6H7Qb+CC/g2Mjbh62sE9zLrn4 JD9h8OySGxuBj5Wrp1FTw3vQV9PHizuYC5ef1iK73KG7yOcMxQ6giMC+SUMruvLxpWWJIq3UCG1Tv BXHEEqrtw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kNz4g-0005C1-8P; Thu, 01 Oct 2020 13:56:46 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kNz4e-0005Aj-Cd for linux-arm-kernel@lists.infradead.org; Thu, 01 Oct 2020 13:56:45 +0000 Received: from localhost (fla63-h02-176-172-189-251.dsl.sta.abo.bbox.fr [176.172.189.251]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2B5A720872; Thu, 1 Oct 2020 13:56:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601560602; bh=o6qC8bC+K4scG1XPUArlJlnEglhhA7NyUzceP6nkYdI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=MXeH6FmIoCrfau0W+WEVxQ2VRPiAykZjm2GMGlUsh12yFePp1P8OfDU9y4YF/flEM MSbl46cqF3QyJirMrdBjRZAVUJJcW7N6F4JPKxVSba6zbSRfU/L6n5//FXQ6rFK+vI RnXQMZb6DOSyo1ig6sI67GlpHT7Y41BHNna95WqI= Date: Thu, 1 Oct 2020 15:56:40 +0200 From: Frederic Weisbecker To: Alex Belits Subject: Re: [PATCH v4 03/13] task_isolation: userspace hard isolation from kernel Message-ID: <20201001135640.GA1748@lothringen> References: <04be044c1bcd76b7438b7563edc35383417f12c8.camel@marvell.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201001_095644_499692_8900A764 X-CRM114-Status: GOOD ( 14.49 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "linux-arch@vger.kernel.org" , "catalin.marinas@arm.com" , "peterz@infradead.org" , Prasun Kapoor , "linux-kernel@vger.kernel.org" , "rostedt@goodmis.org" , "davem@davemloft.net" , "netdev@vger.kernel.org" , "linux-api@vger.kernel.org" , "tglx@linutronix.de" , "will@kernel.org" , "mingo@kernel.org" , "linux-arm-kernel@lists.infradead.org" Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jul 22, 2020 at 02:49:49PM +0000, Alex Belits wrote: > +/* > + * Description of the last two tasks that ran isolated on a given CPU. > + * This is intended only for messages about isolation breaking. We > + * don't want any references to actual task while accessing this from > + * CPU that caused isolation breaking -- we know nothing about timing > + * and don't want to use locking or RCU. > + */ > +struct isol_task_desc { > + atomic_t curr_index; > + atomic_t curr_index_wr; > + bool warned[2]; > + pid_t pid[2]; > + pid_t tgid[2]; > + char comm[2][TASK_COMM_LEN]; > +}; > +static DEFINE_PER_CPU(struct isol_task_desc, isol_task_descs); So that's quite a huge patch that would have needed to be split up. Especially this tracing engine. Speaking of which, I agree with Thomas that it's unnecessary. It's too much code and complexity. We can use the existing trace events and perform the analysis from userspace to find the source of the disturbance. Thanks. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel