From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757403Ab2FOS6s (ORCPT ); Fri, 15 Jun 2012 14:58:48 -0400 Received: from e36.co.us.ibm.com ([32.97.110.154]:58752 "EHLO e36.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757324Ab2FOS6d (ORCPT ); Fri, 15 Jun 2012 14:58:33 -0400 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@elte.hu, laijs@cn.fujitsu.com, dipankar@in.ibm.com, akpm@linux-foundation.org, mathieu.desnoyers@polymtl.ca, josh@joshtriplett.org, niv@us.ibm.com, tglx@linutronix.de, peterz@infradead.org, rostedt@goodmis.org, Valdis.Kletnieks@vt.edu, dhowells@redhat.com, eric.dumazet@gmail.com, darren@dvhart.com, fweisbec@gmail.com, patches@linaro.org, "Paul E. McKenney" , "Paul E. McKenney" Subject: [PATCH tip/core/rcu 6/6] rcu: Make rcutorture fakewriters invoke rcu_barrier() Date: Fri, 15 Jun 2012 11:57:54 -0700 Message-Id: <1339786674-25265-6-git-send-email-paulmck@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.8 In-Reply-To: <1339786674-25265-1-git-send-email-paulmck@linux.vnet.ibm.com> References: <20120615185725.GA25163@linux.vnet.ibm.com> <1339786674-25265-1-git-send-email-paulmck@linux.vnet.ibm.com> X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12061518-7606-0000-0000-000001286DA3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Paul E. McKenney" The current rcutorture rcu_barrier() testing never intentionally runs more than one instance of rcu_barrier() at a given time. This fails to test the the shiny new concurrency features of rcu_barrier(). This commit therefore modifies the rcutorture fakewriter kthread to randomly invoke rcu_barrier() rather than the usual synchronize_rcu(). Signed-off-by: Paul E. McKenney Signed-off-by: Paul E. McKenney --- kernel/rcutorture.c | 6 +++++- 1 files changed, 5 insertions(+), 1 deletions(-) diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c index 54a3745..dfb4e20 100644 --- a/kernel/rcutorture.c +++ b/kernel/rcutorture.c @@ -1025,7 +1025,11 @@ rcu_torture_fakewriter(void *arg) do { schedule_timeout_uninterruptible(1 + rcu_random(&rand)%10); udelay(rcu_random(&rand) & 0x3ff); - cur_ops->sync(); + if (cur_ops->cb_barrier != NULL && + rcu_random(&rand) % (NR_CPUS * 8) == 0) + cur_ops->cb_barrier(); + else + cur_ops->sync(); rcu_stutter_wait("rcu_torture_fakewriter"); } while (!kthread_should_stop() && fullstop == FULLSTOP_DONTSTOP); -- 1.7.8