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 11565CE7A8B for ; Sat, 23 Sep 2023 09:39:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231256AbjIWJjx (ORCPT ); Sat, 23 Sep 2023 05:39:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42666 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231313AbjIWJjs (ORCPT ); Sat, 23 Sep 2023 05:39:48 -0400 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3EF60196; Sat, 23 Sep 2023 02:39:40 -0700 (PDT) Received: from [IPV6:2001:818:e7d2:8300:2412:6733:7e63:fb46] (unknown [IPv6:2001:818:e7d2:8300:2412:6733:7e63:fb46]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 5EDF1DE2; Sat, 23 Sep 2023 11:37:58 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1695461879; bh=5rwlDgb18LMeY6PGIIJDEvGpiQq5OlIONr+fS/lgUek=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=CAVJ32rItefld/CVJeWF3kknOncqbkl/dVP+UY1mUPtkblGiMPQ7X7k7EmDFeEjeb wpm7IlcB+e0NQRHZsjp9zdLHdGULQ1VYJKNmp5XLlJdnayesIRnhbind0sH+Bm7uNv V1XkfDVEafukNtLhIgk1GP5YkReXKQenpDdTdYgM= Message-ID: <3f040e44-3bdc-b09c-58b3-ea3b0ac6d5dd@ideasonboard.com> Date: Sat, 23 Sep 2023 15:09:33 +0530 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.10.0 Subject: Re: [RFC PATCH v2 0/4] staging: vc04: Drop custom logging To: Stefan Wahren , Dan Carpenter Cc: linux-staging@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-rpi-kernel@lists.infradead.org, linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, Greg Kroah-Hartman , Florian Fainelli , Adrien Thierry , Dan Carpenter , Dave Stevenson , Kieran Bingham , Laurent Pinchart , Phil Elwell References: <20230913185528.770634-1-umang.jain@ideasonboard.com> <1d54715d-25f9-4937-bdff-de0136c95fe8@kadam.mountain> Content-Language: en-US From: Umang Jain In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Stefan, On 9/17/23 9:06 PM, Stefan Wahren wrote: > Hi, > > Am 14.09.23 um 08:35 schrieb Dan Carpenter: >> On Thu, Sep 14, 2023 at 12:25:24AM +0530, Umang Jain wrote: >>> Hello, >>> >>> This series attempts to restart the discussion on custom logging used >>> in VC04. In the last feedback gathered in [1] it seems that the logging >>> would rather be moved to use dynamic debug. The series tries to move >>> in that direction. >>> >>> The elephant in the room is the ability of turning on/off log levels, >>> which this series just drops. Compensated by a crude strings >>> ("error", "warning", "info"... etc) for easier grepping. >>> >>> The log category are also just strings (which probably can be >>> transformed >>> to dynamic debug class names moving forwards?). >>> >>> To move forwards, I would like feedback on the broader direction. >>> There are couple of TODOs in each of the patch (summarised in commit >>> messages) which require case-by-case discussion. >>> >>> Additional high-level questions to move forwards: >>> 1. Is loss of log levels by moving to dynamic debug, is actually a >>>     concern? Is dynamic debug a valid replacement? >> >> Dynamic debug is honestly going to be an improvement.  I guess, Greg and >> I said this back in Jan. +1 >> >>> 2. Whether debugfs should be dropped as well, found vestigial in [2] >> >> Yes. The "vchiq/log" should be removed.  Ideally as part of this >> patchset so it's easier to understand. > > Yes, but please do not remote vchiq_debugfs entirely. I'm working on a > patch to move the state dump (debug feature) from the character device > /dev/vchiq to debugfs /sys/kernel/debug/vchiq/dump_state. Can't the state dump be printed to dev_dbg() ? Will it pollute the kernel log?  Having debugfs for a single dump doesn't seem worthwhile if the state dump can be incorporated to dev_dbg() too. > >> >>> 3. whether vchiq_log_trace() should actually be tracing support for >>> VC04 >> >> That can be done later if people want.  No need to discuss it now. Thanks Dan. >> >> regards, >> dan carpenter >>