Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932661AbWAFHrl (ORCPT ); Fri, 6 Jan 2006 02:47:41 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932662AbWAFHrk (ORCPT ); Fri, 6 Jan 2006 02:47:40 -0500 Received: from linux01.gwdg.de ([134.76.13.21]:54408 "EHLO linux01.gwdg.de") by vger.kernel.org with ESMTP id S932660AbWAFHrj (ORCPT ); Fri, 6 Jan 2006 02:47:39 -0500 Date: Fri, 6 Jan 2006 08:47:02 +0100 (MET) From: Jan Engelhardt To: Hannu Savolainen cc: Takashi Iwai , linux-sound@vger.kernel.org, LKML Subject: Re: [OT] ALSA userspace API complexity In-Reply-To: Message-ID: References: <20050726150837.GT3160@stusta.de> <20060103193736.GG3831@stusta.de> <20060104030034.6b780485.zaitcev@redhat.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1386 Lines: 32 >> > If you have sound device without this soft mixing is moved to user space >> > .. but applications do not need know about this even now because all >> > neccessary details are handled on library level. Is it ? >> > So question is: why the hell *ALL* mixing details are not moved to kernel >> > space to SIMPLE and NOT GROWING abstraction ? >> >> Because many people believe that the softmix in the kernel space is >> evil. >> >This is the usual argument against kernel level mixing. Somebody has once >said that all this is evil. However this is not necessarily correct. > I'm going with "is evil". Better let userspace have a segfault than a kernel oops. I am having quite a moody feeling when running even my own things like http://alphagate.hopto.org/quad_dsp/ >Kernel mixing is not rocket science. All you need to do is picking a >sample from the output buffers of each of the applications, sum them >together (with some volume scaling) and feed the result to the physical >device. Ok, handling different sample formats/rates makes it much more >difficult but that could be done in the library level. Jan Engelhardt -- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/