From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750782AbWC2JLT (ORCPT ); Wed, 29 Mar 2006 04:11:19 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750789AbWC2JLS (ORCPT ); Wed, 29 Mar 2006 04:11:18 -0500 Received: from omx2-ext.sgi.com ([192.48.171.19]:46533 "EHLO omx2.sgi.com") by vger.kernel.org with ESMTP id S1750782AbWC2JLR (ORCPT ); Wed, 29 Mar 2006 04:11:17 -0500 From: Paul Jackson To: Andrew Morton Cc: Simon.Derr@bull.net, Paul Jackson , linux-kernel@vger.kernel.org, clameter@sgi.com Date: Wed, 29 Mar 2006 01:11:08 -0800 Message-Id: <20060329091108.14612.84403.sendpatchset@jackhammer.engr.sgi.com> Subject: [PATCH 01/03] Cpuset: task_lock comment fix Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org From: Paul Jackson Fix cpuset comment involving case of a tasks cpuset pointer being NULL. Thanks to "the_top_cpuset_hack", this code no longer sees NULL task->cpuset pointers. Signed-off-by: Paul Jackson --- kernel/cpuset.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) --- 2.6.16-mm1.orig/kernel/cpuset.c 2006-03-27 08:44:45.794087744 -0800 +++ 2.6.16-mm1/kernel/cpuset.c 2006-03-28 16:06:02.862014854 -0800 @@ -616,12 +616,10 @@ static void guarantee_online_mems(const * current->cpuset if a task has its memory placement changed. * Do not call this routine if in_interrupt(). * - * Call without callback_mutex or task_lock() held. May be called - * with or without manage_mutex held. Doesn't need task_lock to guard - * against another task changing a non-NULL cpuset pointer to NULL, - * as that is only done by a task on itself, and if the current task - * is here, it is not simultaneously in the exit code NULL'ing its - * cpuset pointer. This routine also might acquire callback_mutex and + * Call without callback_mutex or task_lock() held. May be + * called with or without manage_mutex held. Thanks in part to + * 'the_top_cpuset_hack', the tasks cpuset pointer will never + * be NULL. This routine also might acquire callback_mutex and * current->mm->mmap_sem during call. * * Reading current->cpuset->mems_generation doesn't need task_lock -- I won't rest till it's the best ... Programmer, Linux Scalability Paul Jackson 1.650.933.1373