Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 6 Feb 2002 10:04:16 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 6 Feb 2002 10:04:06 -0500 Received: from 167.imtp.Ilyichevsk.Odessa.UA ([195.66.192.167]:62213 "EHLO Port.imtp.ilyichevsk.odessa.ua") by vger.kernel.org with ESMTP id ; Wed, 6 Feb 2002 10:04:00 -0500 Message-Id: <200202061402.g16E2Nt32223@Port.imtp.ilyichevsk.odessa.ua> Content-Type: text/plain; charset=US-ASCII From: Denis Vlasenko Reply-To: vda@port.imtp.ilyichevsk.odessa.ua To: Andi Kleen Subject: Re: kernel: ldt allocation failed Date: Wed, 6 Feb 2002 16:02:25 -0200 X-Mailer: KMail [version 1.3.2] Cc: linux-kernel@vger.kernel.org In-Reply-To: <200202061258.g16CwGt31197@Port.imtp.ilyichevsk.odessa.ua.suse.lists.linux.kernel> In-Reply-To: MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 6 February 2002 11:19, Andi Kleen wrote: > Denis Vlasenko writes: > > I am ignorant on the subject, but why LDT is used in Linux at all? > > LDT register can be set to 0, this can speed up task switch time and save > > some memory used for LDT. > > glibc thread local data uses an LDT for the segment register. > > glibc 2.3 seems to plan to use segment register based thread local data for > even non threaded programs, so it would be a good idea to optimize LDT > allocation a bit (= not allocate 64K of vmalloc space every time > sys_modify_ldt is called - there is only 8MB of it) What do they use on arches without LDT or equivalent? -- vda - 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/