From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-pj1-x1041.google.com ([2607:f8b0:4864:20::1041]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1k6BSk-0003WZ-O5 for kexec@lists.infradead.org; Thu, 13 Aug 2020 11:32:03 +0000 Received: by mail-pj1-x1041.google.com with SMTP id kr4so2644488pjb.2 for ; Thu, 13 Aug 2020 04:32:00 -0700 (PDT) Date: Thu, 13 Aug 2020 20:31:55 +0900 From: Sergey Senozhatsky Subject: Re: [RFC PATCH] printk: Change timestamp to triplet as mono, boot and real Message-ID: <20200813113155.GA483@jagdpanzerIV.localdomain> References: <1597120822-11999-1-git-send-email-orsonzhai@gmail.com> <20200811094413.GA12903@alley> <87zh7175hj.fsf@nanos.tec.linutronix.de> <20200811130218.GI6215@alley> <20200813015500.GC2020879@jagdpanzerIV.localdomain> <20200813102258.GL12903@alley> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200813102258.GL12903@alley> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Petr Mladek Cc: Dominique Martinet , ruifeng.zhang1@unisoc.com, Steven Sistare , Prarit Bhargava , Baoquan He , zhang.lyra@gmail.com, cixi.geng1@unisoc.com, Orson Zhai , Dave Young , Vivek Goyal , Pavel Tatashin , John Ogness , Steven Rostedt , Jon DeVree , Thomas Gleixner , Salvatore Bonaccorso , Stephen Boyd , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, Sergey Senozhatsky , Orson Zhai , John Stultz On (20/08/13 12:22), Petr Mladek wrote: > > + would take more space (prefix + text vs. binary representation) Dict buffer is allocated regardless of how we use it, and only printks from drivers/* (dev_printk*) add dict payload. It might be the case that on some (if not most) systems dict pages are not used 90% of times (if not 99%). > + not reliable because dict is currently dropped when no space Well, in the perfect world this is a problem, but "maybe not having alternative timestamps sometimes" can be OK approach for people who wants to use those triplet timestamps. But, in general, how real this problem is? What I sae so far (on my boxes) was that printk messages are longer than dict payload. Example: 6,223,93298,-,caller=T1;acpi PNP0A08:00: _OSC: OS supports [Segments MSI HPX-Type3] SUBSYSTEM=acpi DEVICE=+acpi:PNP0A08:00 6,224,93413,-,caller=T1;acpi PNP0A08:00: _OSC: not requesting OS control; OS requires [ExtendedConfig ASPM ClockPM MSI] SUBSYSTEM=acpi DEVICE=+acpi:PNP0A08:00 6,225,93540,-,caller=T1;PCI host bridge to bus 0000:00 6,226,93541,-,caller=T1;pci_bus 0000:00: root bus resource [io 0x0000-0x0cf7 window] SUBSYSTEM=pci_bus DEVICE=+pci_bus:0000:00 It might be the case, that overflowing dict buffer, without first overflowing printk buffer, can be rather challenging. > + it would make the controversial dictionary feature more important Yes. But, for the time being, this controversial dict feature allocates pages for dict buffer anyway. -ss _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec 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=-4.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,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 B65BBC433DF for ; Thu, 13 Aug 2020 11:32:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 933CD20885 for ; Thu, 13 Aug 2020 11:32:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Af27m4tR" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726593AbgHMLb7 (ORCPT ); Thu, 13 Aug 2020 07:31:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43158 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726100AbgHMLb7 (ORCPT ); Thu, 13 Aug 2020 07:31:59 -0400 Received: from mail-pj1-x1044.google.com (mail-pj1-x1044.google.com [IPv6:2607:f8b0:4864:20::1044]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4ADBAC061757 for ; Thu, 13 Aug 2020 04:31:59 -0700 (PDT) Received: by mail-pj1-x1044.google.com with SMTP id kr4so2644489pjb.2 for ; Thu, 13 Aug 2020 04:31:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=TdxvYAjwHYBqX28RZ+WzNUpjs3QbINtn5/MRyyS8TLo=; b=Af27m4tRbZiKQS9zEInh/cKxpGWSJD1wgUrpOo5G0oLOElEFVrOLsUX9sVA5J2UGOH 4LyRrSz+9a63Niw44hGv8m7iRFZScwB381gbrBzxwMcvHFBkfM+49Rfvshvkzit9+wz5 Lpv9KC6Eg/WWEV42aS2o5jtEJiE2GBX85cnLWSIadobWwJJjvkES9NatQ2T/GoMjiUlf lv+20AvFvJP7qsv19Ma5hYDm2G7GgaiK9eddERpGH3lGiZMyPJt84FInkqG1d/YKh1+M UkW47z5HuZnPZDTPomajhatqxwFGwML9BU55CHkScLu3W/oeuXKVnaG2OZStAhyTtGN9 3k+w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=TdxvYAjwHYBqX28RZ+WzNUpjs3QbINtn5/MRyyS8TLo=; b=mQDrN3JeCNLH8gNtVIsdvBLiyS9rIeEaYBfqO9aW/8AaoNiFwCFTkrXzSdm25bIE7r 0EYB9EvlvuqJzWjSPd/8O4ip8gCqsx6mf4JpTk9BSy5vs8cAVItesb31+lu+HPZuemNH CZFtElz7B+6R8+fLyQPdyFTHPXQVsj1tspUBbrvlXkXKfjgw+e0vKeNifxo4MiOTVljE DMxMGD7EkLoP9PkwZJ93zXhOaOGCbDVQlF6R/h682Xb5R6KQiLuqnTjGnEZubrKAleZV fCTMKlcdNZWy125YNIunX6XJPtio4iPKPCFI531PoICOomMesTcMFjICjgzIfzW2OezS Xlgg== X-Gm-Message-State: AOAM531WoBOG0yunmTggPEvZgixDxsv6H351B3qcNWh7UYuv4YiZh/SA rjCHm6SJbKlU443iad1+Z9U= X-Google-Smtp-Source: ABdhPJxa5aZAJ/Gekwq4D8YGUYdMsa4IUsup7BXdrpnf/npn/T7/PejRDXRAWvZ+Jl5PU+BSK2nCVQ== X-Received: by 2002:a17:90a:9b88:: with SMTP id g8mr4586084pjp.143.1597318318744; Thu, 13 Aug 2020 04:31:58 -0700 (PDT) Received: from localhost ([2409:10:2e40:5100:6e29:95ff:fe2d:8f34]) by smtp.gmail.com with ESMTPSA id a24sm5611736pfg.113.2020.08.13.04.31.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 13 Aug 2020 04:31:57 -0700 (PDT) Date: Thu, 13 Aug 2020 20:31:55 +0900 From: Sergey Senozhatsky To: Petr Mladek Cc: Sergey Senozhatsky , Thomas Gleixner , Orson Zhai , Prarit Bhargava , Dave Young , Baoquan He , Vivek Goyal , Steven Rostedt , John Stultz , Stephen Boyd , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, zhang.lyra@gmail.com, ruifeng.zhang1@unisoc.com, cixi.geng1@unisoc.com, Orson Zhai , Pavel Tatashin , Steven Sistare , Dominique Martinet , Jon DeVree , Salvatore Bonaccorso , John Ogness Subject: Re: [RFC PATCH] printk: Change timestamp to triplet as mono, boot and real Message-ID: <20200813113155.GA483@jagdpanzerIV.localdomain> References: <1597120822-11999-1-git-send-email-orsonzhai@gmail.com> <20200811094413.GA12903@alley> <87zh7175hj.fsf@nanos.tec.linutronix.de> <20200811130218.GI6215@alley> <20200813015500.GC2020879@jagdpanzerIV.localdomain> <20200813102258.GL12903@alley> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200813102258.GL12903@alley> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (20/08/13 12:22), Petr Mladek wrote: > > + would take more space (prefix + text vs. binary representation) Dict buffer is allocated regardless of how we use it, and only printks from drivers/* (dev_printk*) add dict payload. It might be the case that on some (if not most) systems dict pages are not used 90% of times (if not 99%). > + not reliable because dict is currently dropped when no space Well, in the perfect world this is a problem, but "maybe not having alternative timestamps sometimes" can be OK approach for people who wants to use those triplet timestamps. But, in general, how real this problem is? What I sae so far (on my boxes) was that printk messages are longer than dict payload. Example: 6,223,93298,-,caller=T1;acpi PNP0A08:00: _OSC: OS supports [Segments MSI HPX-Type3] SUBSYSTEM=acpi DEVICE=+acpi:PNP0A08:00 6,224,93413,-,caller=T1;acpi PNP0A08:00: _OSC: not requesting OS control; OS requires [ExtendedConfig ASPM ClockPM MSI] SUBSYSTEM=acpi DEVICE=+acpi:PNP0A08:00 6,225,93540,-,caller=T1;PCI host bridge to bus 0000:00 6,226,93541,-,caller=T1;pci_bus 0000:00: root bus resource [io 0x0000-0x0cf7 window] SUBSYSTEM=pci_bus DEVICE=+pci_bus:0000:00 It might be the case, that overflowing dict buffer, without first overflowing printk buffer, can be rather challenging. > + it would make the controversial dictionary feature more important Yes. But, for the time being, this controversial dict feature allocates pages for dict buffer anyway. -ss