Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752531AbXACAwP (ORCPT ); Tue, 2 Jan 2007 19:52:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752532AbXACAwP (ORCPT ); Tue, 2 Jan 2007 19:52:15 -0500 Received: from moutng.kundenserver.de ([212.227.126.187]:57406 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752531AbXACAwO (ORCPT ); Tue, 2 Jan 2007 19:52:14 -0500 X-Greylist: delayed 316 seconds by postgrey-1.27 at vger.kernel.org; Tue, 02 Jan 2007 19:52:13 EST From: Bodo Eggert <7eggert@gmx.de> Subject: Re: Shrink the held_lock struct by using bitfields. To: Dave Jones , mingo@redhat.com, Linux Kernel Reply-To: 7eggert@gmx.de Date: Wed, 03 Jan 2007 01:47:36 +0100 References: <7z1oG-6Jr-5@gated-at.bofh.it> User-Agent: KNode/0.7.2 MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8Bit Message-Id: X-be10.7eggert.dyndns.org-MailScanner-Information: See www.mailscanner.info for information X-be10.7eggert.dyndns.org-MailScanner: Found to be clean X-be10.7eggert.dyndns.org-MailScanner-From: 7eggert@gmx.de X-Provags-ID: kundenserver.de abuse@kundenserver.de login:9b3b2cc444a07783f194c895a09f1de9 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 910 Lines: 28 Dave Jones wrote: > Shrink the held_lock struct by using bitfields. > This shrinks task_struct on lockdep enabled kernels by 480 bytes. > * The following field is used to detect when we cross into an > * interrupt context: > */ > - int irq_context; [...] > + unsigned char irq_context:1; [...] Can these fields be set by concurrent processes, e.g.: CPU0 CPU1 load flags load flags flip bit store flip bit store ? -- Ich danke GMX daf?r, die Verwendung meiner Adressen mittels per SPF verbreiteten L?gen zu sabotieren. http://david.woodhou.se/why-not-spf.html - 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/