From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933275AbaE3O60 (ORCPT ); Fri, 30 May 2014 10:58:26 -0400 Received: from mout.gmx.net ([212.227.17.22]:61398 "EHLO mout.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932699AbaE3O6Z convert rfc822-to-8bit (ORCPT ); Fri, 30 May 2014 10:58:25 -0400 Message-ID: <1401461863.4646.9.camel@schoellingm.dzne.de> Subject: Re: [PATCH] console: Add persistent scrollback buffers for all VGA consoles From: Manuel Schoelling To: Geert Uytterhoeven Cc: Jean-Christophe PLAGNIOL-VILLARD , Tomi Valkeinen , Mark Brown , Randy Dunlap , David Herrmann , Dave Airlie , Marcelo Tosatti , Linux Fbdev development list , "linux-kernel@vger.kernel.org" Date: Fri, 30 May 2014 16:57:43 +0200 In-Reply-To: References: <1401456425-15931-1-git-send-email-manuel.schoelling@gmx.de> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.4.4-3 Mime-Version: 1.0 Content-Transfer-Encoding: 8BIT X-Provags-ID: V03:K0:mqHksVmcsKmYTWpdvOpQMhjx1QPOHoOJE4ad09zCULf93kOz2p4 weEXUU3yCA0EWcI953oxszEp3Qv0Kq3vibZ8nltCr85jF1l/DkXyLOSEloyqgQaNPPmXlJ4 ZUm8km4nd4v9g7ZzPgJPq85Ml+9MWFdxCIDe5S6YzbZM35Hg0hAQjKMiT2HPlq5w+fdcfGR 8ART4OtpNJcRy6bfstisQ== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Geert, On Fr, 2014-05-30 at 16:28 +0200, Geert Uytterhoeven wrote: Hi Manuel, > > On Fri, May 30, 2014 at 3:27 PM, Manuel Schölling > wrote: > > Add a scrollback buffers for each VGA console. The benefit is that > > the scrollback history is not flushed when switching between consoles > > but is persistent. > > The buffers are allocated on demand when a new console is opened. > > Thanks for your patch! > > I see two issues with this feature: > 1. Before, the single (default 64 KiB) buffer was allocated at startup. > Now you will allocate a buffer each time a new console is opened. > Depending on memory fragmentation, this may fail. Indeed, if allocation fails, scrollbuffer[vc_num]->data will stay NULL and scrolling will be disabled for that console. Is that ok or would you prefer another behavior of the kernel? > 2. People with RAM-constrained systems may not like this. > Can it be a config option? Sure, I will add an option for that. > > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds >