Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759993AbXF0FCz (ORCPT ); Wed, 27 Jun 2007 01:02:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753515AbXF0FCf (ORCPT ); Wed, 27 Jun 2007 01:02:35 -0400 Received: from wa-out-1112.google.com ([209.85.146.180]:43475 "EHLO wa-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753178AbXF0FCe (ORCPT ); Wed, 27 Jun 2007 01:02:34 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=NGPqoH+DnhaOK6JiOAV9bu59VcuiRgQH+79M9HAZKzuwaMnfkGFCvrixA7kdyCUdpzh3jAUgtfuyiU+JY/ZWee8oKaJl9m3Dg10vzDxYmSar6/zGraaWQW01BGv6QFMyZqcjWNWxf8KYm1dkZ71jQJjenBg+s+j7pn8i3sthZ64= Message-ID: Date: Tue, 26 Jun 2007 22:02:33 -0700 From: "Ulrich Drepper" To: "Davide Libenzi" Subject: Re: [patch 2/3] MAP_NOZERO - implement sys_brk2() Cc: "Linux Kernel Mailing List" In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 939 Lines: 21 On 6/26/07, Davide Libenzi wrote: > I acutally have the code for it, but I never posted it since it did not > receive a too warm review (and the only user was the fdmap thingy). Only user of sys_indirect? There will be quite a few right away. Every syscall that returns a file descriptor needs O_CLOEXEC support (socket, pipe, epoll_create, ...) > OTOH glibc could implement __morecore using mmap(MAP_NOZERO), and hence > brk2() would not be needed, no? No. mmap calls create individual VMAs which gets expensive. There are also some hardware drivers which get more expensive the more VMAs there are. I want to go away as much as possible from mmap for malloc. - 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/