From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755599AbbGQXpy (ORCPT ); Fri, 17 Jul 2015 19:45:54 -0400 Received: from e33.co.us.ibm.com ([32.97.110.151]:37936 "EHLO e33.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754867AbbGQXpq (ORCPT ); Fri, 17 Jul 2015 19:45:46 -0400 X-Helo: d03dlp01.boulder.ibm.com X-MailFrom: paulmck@linux.vnet.ibm.com X-RcptTo: linux-kernel@vger.kernel.org From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@efficios.com, josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com, dvhart@linux.intel.com, fweisbec@gmail.com, oleg@redhat.com, bobby.prani@gmail.com, "Paul E. McKenney" Subject: [PATCH tip/core/rcu 5/6] rcutorture: Add RCU-tasks qualifier to dereference Date: Fri, 17 Jul 2015 16:45:36 -0700 Message-Id: <1437176737-26668-5-git-send-email-paulmck@linux.vnet.ibm.com> X-Mailer: git-send-email 1.8.1.5 In-Reply-To: <1437176737-26668-1-git-send-email-paulmck@linux.vnet.ibm.com> References: <20150717234518.GA26072@linux.vnet.ibm.com> <1437176737-26668-1-git-send-email-paulmck@linux.vnet.ibm.com> X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15071723-0009-0000-0000-00000C91A8B7 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Paul E. McKenney" Although RCU-tasks isn't really designed to support rcu_dereference() and list manipulation, that is how rcutorture tests it. Which means that lockdep-RCU complains about the rcu_dereference_check() invocations because RCU-tasks doesn't have read-side markers. This commit therefore creates a torturing_tasks() to silence the lockdep-RCU complaints from rcu_dereference_check() when RCU-tasks is being tortured. Signed-off-by: Paul E. McKenney --- kernel/rcu/rcutorture.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index e0eda3c1b621..67b3f260720e 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -684,10 +684,20 @@ static struct rcu_torture_ops tasks_ops = { #define RCUTORTURE_TASKS_OPS &tasks_ops, +static bool __maybe_unused torturing_tasks(void) +{ + return cur_ops == &tasks_ops; +} + #else /* #ifdef CONFIG_TASKS_RCU */ #define RCUTORTURE_TASKS_OPS +static bool torturing_tasks(void) +{ + return false; +} + #endif /* #else #ifdef CONFIG_TASKS_RCU */ /* @@ -1087,7 +1097,8 @@ static void rcu_torture_timer(unsigned long unused) p = rcu_dereference_check(rcu_torture_current, rcu_read_lock_bh_held() || rcu_read_lock_sched_held() || - srcu_read_lock_held(srcu_ctlp)); + srcu_read_lock_held(srcu_ctlp) || + torturing_tasks()); if (p == NULL) { /* Leave because rcu_torture_writer is not yet underway */ cur_ops->readunlock(idx); @@ -1161,7 +1172,8 @@ rcu_torture_reader(void *arg) p = rcu_dereference_check(rcu_torture_current, rcu_read_lock_bh_held() || rcu_read_lock_sched_held() || - srcu_read_lock_held(srcu_ctlp)); + srcu_read_lock_held(srcu_ctlp) || + torturing_tasks()); if (p == NULL) { /* Wait for rcu_torture_writer to get underway */ cur_ops->readunlock(idx); -- 1.8.1.5