Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754986AbdDECQb (ORCPT ); Tue, 4 Apr 2017 22:16:31 -0400 Received: from mail-pf0-f196.google.com ([209.85.192.196]:34941 "EHLO mail-pf0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754583AbdDECQ2 (ORCPT ); Tue, 4 Apr 2017 22:16:28 -0400 Date: Wed, 5 Apr 2017 11:16:28 +0900 From: Sergey Senozhatsky To: Calvin Owens Cc: Petr Mladek , Steven Rostedt , Greg Kroah-Hartman , Jiri Slaby , Andrew Morton , Manuel =?iso-8859-1?Q?Sch=F6lling?= , Hans de Goede , Paul Burton , linux-kernel@vger.kernel.org, kernel-team@fb.com, Sergey Senozhatsky , Sergey Senozhatsky Subject: Re: [RFC][PATCH 1/2] printk: Introduce per-console filtering of messages by loglevel Message-ID: <20170405021628.GC11669@jagdpanzerIV.localdomain> References: <20170405020800.GB11669@jagdpanzerIV.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170405020800.GB11669@jagdpanzerIV.localdomain> User-Agent: Mutt/1.8.0 (2017-02-23) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1471 Lines: 53 On (04/05/17 11:08), Sergey Senozhatsky wrote: [..] > > stop_critical_timings(); /* don't trace print latency */ > > - call_console_drivers(ext_text, ext_len, text, len); > > + call_console_drivers(ext_text, ext_len, text, len, msg->level); > > start_critical_timings(); > > printk_safe_exit_irqrestore(flags); > > ok, so the idea is quite clear and reasonable. > > > some thoughts, > we have a system-wide suppress_message_printing() loglevel filtering > in console_unlock() loop, which sets a limit on loglevel for all of > the messages - we don't even msg_print_text() if the message has > suppressible loglevel. and this implicitly restricts per-console > maxlevels. > > console_unlock() > { > for (;;) { > ... > skip: > > if (suppress_message_printing(msg->level)) // console_loglevel > goto skip; > > call_console_drivers(msg->level) > { > if (level > con->maxlevel) // con loglevel > continue; > ... > } > } > } > > this can be slightly confusing. what do you think? one more thing. this per-console filtering ignores... the "ignore_loglevel" param. early_param("ignore_loglevel", ignore_loglevel_setup); module_param(ignore_loglevel, bool, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(ignore_loglevel, "ignore loglevel setting (prints all kernel messages to the console)"); my preference would be preserve "ignore_loglevel" behaviour. if we are forced to 'ignore all loglevel filtering' then we should do so. -ss