Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757244AbYHMSX2 (ORCPT ); Wed, 13 Aug 2008 14:23:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751164AbYHMSXU (ORCPT ); Wed, 13 Aug 2008 14:23:20 -0400 Received: from mx1.redhat.com ([66.187.233.31]:43564 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750970AbYHMSXT (ORCPT ); Wed, 13 Aug 2008 14:23:19 -0400 Message-ID: <48A3266F.9000908@redhat.com> Date: Wed, 13 Aug 2008 11:22:39 -0700 From: Ulrich Drepper Organization: Red Hat, Inc. User-Agent: Thunderbird 2.0.0.16 (X11/20080723) MIME-Version: 1.0 To: Arjan van de Ven CC: Linus Torvalds , Ingo Molnar , akpm@linux-foundation.org, hugh@veritas.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org, briangrant@google.com, cgd@google.com, mbligh@google.com, Thomas Gleixner , "H. Peter Anvin" Subject: Re: pthread_create() slow for many threads; also time to revisit 64b context switch optimization? References: <20080813104445.GA24632@elte.hu> <20080813063533.444c650d@infradead.org> <48A2EE07.3040003@redhat.com> <20080813142529.GB21129@elte.hu> <48A2F157.7000303@redhat.com> <20080813151007.GA8780@elte.hu> <48A2FC17.9070302@redhat.com> <20080813154043.GA11886@elte.hu> <48A303EE.8070002@redhat.com> <48A3222D.2060809@redhat.com> <20080813111635.657febc0@infradead.org> In-Reply-To: <20080813111635.657febc0@infradead.org> X-Enigmail-Version: 0.95.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1016 Lines: 28 -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Arjan van de Ven wrote: > yeah maybe we should also tell it we expect it to be used downwards. > Oh wait.. MAP_GROWSDOWN ? MAP_GROWSDOWN is unusable because we have to allocate the entire address range for the stack. Otherwise some other allocation happens in that range and all of a sudden the stack cannot grow as much as needed anymore. These flags really can be removed. They should not be used because they are outright dangerous. - -- ➧ Ulrich Drepper ➧ Red Hat, Inc. ➧ 444 Castro St ➧ Mountain View, CA ❖ -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) iEYEARECAAYFAkijJm8ACgkQ2ijCOnn/RHQ7/wCfcrLJPlKmtY5AC3c+fuX9LGe8 +YwAnRqLCdSQvwOUdsAz8Hq9H3dmnqEA =BKsz -----END PGP SIGNATURE----- -- 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/