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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 1C036C76188 for ; Mon, 22 Jul 2019 14:38:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E477721993 for ; Mon, 22 Jul 2019 14:38:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563806314; bh=nI4H02Rs1Krn9fT6Xdh4P8gDKFBNE1yuNf5PosxFUOY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:List-ID:From; b=cXN4easbyAOg8m+OqOHiEloFlRUUK5LIUd/FkyPwUgQ1aArHk98lTe7uwaFfg1yTS PavCijrs38zAvt37KVd3oWBnhskR1vms2dMJb8b/AWFUwUGWhLJc8cvgdASrzMnGzA vxiD+fLeO2mckMIdt7rbTUIpPcW08kzz3SpDN9y8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730910AbfGVOid (ORCPT ); Mon, 22 Jul 2019 10:38:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:59418 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728189AbfGVOic (ORCPT ); Mon, 22 Jul 2019 10:38:32 -0400 Received: from devnote2 (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (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 C2EF621951; Mon, 22 Jul 2019 14:38:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563806311; bh=nI4H02Rs1Krn9fT6Xdh4P8gDKFBNE1yuNf5PosxFUOY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=RKftx4fgX4wm2P05Sd2ay5mLZCSMLaRLeUuRjV8+CiggE+5MTLRVJkAVHZ8No/j1E 23Z+Dd6LRmnmkYW+PgWu/iKTyYNIdVJt/2bACs/dTyFcnWFzRNZZyKJapFz6k55gx+ CqqCw5m0yMLwW/6/2PrGZEuHZDCKlktv9nu6+fow= Date: Mon, 22 Jul 2019 23:38:26 +0900 From: Masami Hiramatsu To: Masami Hiramatsu Cc: Frank Rowand , Steven Rostedt , Rob Herring , Tim Bird , Ingo Molnar , Namhyung Kim , Jiri Olsa , Arnaldo Carvalho de Melo , Tom Zanussi , linux-kernel@vger.kernel.org, devicetree@vger.kernel.org Subject: Re: [RFC PATCH v2 00/15] tracing: of: Boot time tracing using devicetree Message-Id: <20190722233826.bafd7aeaad3b821157f2d2ff@kernel.org> In-Reply-To: <20190717000235.9ab100f0dac4af797a0fb76a@kernel.org> References: <156316746861.23477.5815110570539190650.stgit@devnote2> <488a65e6-1d80-0acb-5092-80c18b7ff447@gmail.com> <20190717000235.9ab100f0dac4af797a0fb76a@kernel.org> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, I discussed with Frank and other kernel developers last week at OSSJ 2019. Eventually, I decided to leave from devicetree, because it can unstabilize current devicetree desgin and policy. Instead, aim to introduce a new generic structured kernel cmdline, something like "configtree". I thought JSON or other generic data format, but they look a bit bloated for my purpose. I just need something like "extended hierarchical kernel cmdline". For example, ftrace { options = "sym-addr" events = "initcall:*" tp-printk event.0 { name = "tasl:task_newtask" filter = "pid < 128" } } Which can be written as ftrace.options="sym-addr" ftrace.events="initcall:*" ftrace.tp-printk ftrace.event.0.name="tasl:task_newtask" ftrace.event.0.filter="pid < 128" on current kernel cmdline. So, the parameters are linearly extended from current kernel cmdline. Kernel internal APIs must be able to handle both of current cmdline key-values and configtree key-values. Thank you, -- Masami Hiramatsu