From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932859AbZJFOl7 (ORCPT ); Tue, 6 Oct 2009 10:41:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932850AbZJFOl6 (ORCPT ); Tue, 6 Oct 2009 10:41:58 -0400 Received: from smtp.polymtl.ca ([132.207.4.11]:38669 "EHLO smtp.polymtl.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932821AbZJFOl6 (ORCPT ); Tue, 6 Oct 2009 10:41:58 -0400 Message-Id: <20091006144035.668169139@polymtl.ca> References: <20091006143727.868480435@polymtl.ca> User-Agent: quilt/0.46-1 Date: Tue, 06 Oct 2009 10:37:29 -0400 From: Mathieu Desnoyers To: akpm@linux-foundation.org, Ingo Molnar , linux-kernel@vger.kernel.org, "Paul E. McKenney" Cc: Mathieu Desnoyers Subject: [patch 1/4] kernel call_rcu usage: initialize rcu_head structures Content-Disposition: inline; filename=rcu-init-null.patch X-Poly-FromMTA: (test.casi.polymtl.ca [132.207.72.60]) at Tue, 6 Oct 2009 14:40:37 +0000 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Initialize rcu_head structures before passing them to call_rcu() to eliminate false positives in DEBUG_RCU_HEAD. Signed-off-by: Mathieu Desnoyers CC: "Paul E. McKenney" CC: mingo@elte.hu CC: akpm@linux-foundation.org --- kernel/exit.c | 1 + kernel/pid.c | 1 + kernel/rcupdate.c | 1 + 3 files changed, 3 insertions(+) Index: linux-2.6-lttng/kernel/rcupdate.c =================================================================== --- linux-2.6-lttng.orig/kernel/rcupdate.c 2009-10-06 09:00:06.000000000 -0400 +++ linux-2.6-lttng/kernel/rcupdate.c 2009-10-06 09:01:14.000000000 -0400 @@ -92,6 +92,7 @@ void synchronize_rcu(void) init_completion(&rcu.completion); /* Will wake me after RCU finished. */ + INIT_RCU_HEAD(&rcu.head); call_rcu(&rcu.head, wakeme_after_rcu); /* Wait for it. */ wait_for_completion(&rcu.completion); Index: linux-2.6-lttng/kernel/exit.c =================================================================== --- linux-2.6-lttng.orig/kernel/exit.c 2009-10-06 09:05:21.000000000 -0400 +++ linux-2.6-lttng/kernel/exit.c 2009-10-06 09:05:34.000000000 -0400 @@ -208,6 +208,7 @@ repeat: write_unlock_irq(&tasklist_lock); release_thread(p); + INIT_RCU_HEAD(&p->rcu); call_rcu(&p->rcu, delayed_put_task_struct); p = leader; Index: linux-2.6-lttng/kernel/pid.c =================================================================== --- linux-2.6-lttng.orig/kernel/pid.c 2009-10-06 09:10:59.000000000 -0400 +++ linux-2.6-lttng/kernel/pid.c 2009-10-06 09:11:43.000000000 -0400 @@ -236,6 +236,7 @@ void free_pid(struct pid *pid) for (i = 0; i <= pid->level; i++) free_pidmap(pid->numbers + i); + INIT_RCU_HEAD(&pid->rcu); call_rcu(&pid->rcu, delayed_put_pid); } -- Mathieu Desnoyers OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68