Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750712AbXBMO7N (ORCPT ); Tue, 13 Feb 2007 09:59:13 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750713AbXBMO7N (ORCPT ); Tue, 13 Feb 2007 09:59:13 -0500 Received: from kanga.kvack.org ([66.96.29.28]:36695 "EHLO kanga.kvack.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750712AbXBMO7N (ORCPT ); Tue, 13 Feb 2007 09:59:13 -0500 Date: Tue, 13 Feb 2007 09:58:48 -0500 From: Benjamin LaHaise To: Alan Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Linus Torvalds , Arjan van de Ven , Christoph Hellwig , Andrew Morton , Ulrich Drepper , Zach Brown , Evgeniy Polyakov , "David S. Miller" , Suparna Bhattacharya , Davide Libenzi , Thomas Gleixner Subject: Re: [patch 00/11] ANNOUNCE: "Syslets", generic asynchronous system call support Message-ID: <20070213145848.GS18311@kvack.org> References: <20060529212109.GA2058@elte.hu> <20070213142010.GA638@elte.hu> <20070213150019.4b4d4827@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070213150019.4b4d4827@localhost.localdomain> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 999 Lines: 23 On Tue, Feb 13, 2007 at 03:00:19PM +0000, Alan wrote: > > Open issues: > > Let me add some more Also: FPU state (especially important with the FPU and SSE memory copy variants), segment register bases on x86-64, interaction with set_fs()... There is no easy way of getting around the full thread context switch and its associated overhead (mucking around in CR0 is one of the more expensive bits of the context switch code path, and at the very least, setting the FPU not present is mandatory). I have looked into exactly this approach, and it's only cheaper if the code is incomplete. Linux's native threads are pretty damned good. -ben -- "Time is of no importance, Mr. President, only life is important." Don't Email: . - 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/