From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933077AbbDUTzp (ORCPT ); Tue, 21 Apr 2015 15:55:45 -0400 Received: from e34.co.us.ibm.com ([32.97.110.152]:47043 "EHLO e34.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932630AbbDUTzi (ORCPT ); Tue, 21 Apr 2015 15:55:38 -0400 Date: Tue, 21 Apr 2015 12:55:29 -0700 From: "Paul E. McKenney" To: linux-kernel@vger.kernel.org Cc: mingo@kernel.org, laijs@cn.fujitsu.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 Subject: [PATCH tip/core/rcu 0/12] RCU Kconfig fixes for v4.2 Message-ID: <20150421195529.GA17864@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15042119-0017-0000-0000-00000A388F77 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello! This patch series reduces the number of questions that RCU asks Kconfig users. After this series is applied, removing the RCU-related definitions from .config and running "make oldconfig" results in only the following: RCU Implementation > 1. Tree-based hierarchical RCU (TREE_RCU) (NEW) choice[1]: 1 Make expert-level adjustments to RCU configuration (RCU_EXPERT) [N/y/?] (NEW) Those expert users wishing to tune RCU answer Y to this question. The patches in this series are as follows: 1. Drive TASKS_RCU directly from Kconfig, for example, by having RCU_TORTURE_TESTS select it. 2. Remove CONFIG_TASKS_RCU=y from the three TASKS_RCU test scenarios, since this is set by virtue of having rcutorture configured. 3. Drive RCU_USER_QS directly from Kconfig, relying on the fact that NO_HZ_FULL selects it. 4. Convert CONFIG_RCU_FANOUT_EXACT to a boot parameter, where it is used by rcutorture. 5. Update rcutorture test scenarios to use the boot parameter created in #4 instead of the Kconfig parameter. 6. Create a boot parameter to do a diagnostic dump of the shape of the rcu_node combining tree, which is useful for verifying that intended changes to that tree actually happened. 7. Create an RCU_EXPERT Kconfig parameter and hide the RCU_FAST_NO_HZ, RCU_BOOST, CONTEXT_TRACKING_FORCE, and RCU_NOCB_CPU boolean parameters behind it. 8. Make rcutorture test scenarios force RCU_EXPERT, but have SRCU-P, TASKS03, and TREE09 retain !RCU_EXPERT in order to test the vanilla configuration. 9. Remove the dependency of RCU_FANOUT_LEAF on RCU_FANOUT. 10. Change RCU to allow it to tolerate an undefined RCU_FANOUT, and then hide RCU_FANOUT behind RCU_EXPERT. 11. Change RCU to allow it to tolerate an undefined RCU_FANOUT_LEAF, and then hide RCU_FANOUT_LEAF behind RCU_EXPERT. 12. Change RCU to allow it to tolerate an undefined RCU_KTHREAD_PRIO, and then hide RCU_KTHREAD_PRIO behind RCU_EXPERT. Thanx, Paul ------------------------------------------------------------------------ b/Documentation/kernel-parameters.txt | 11 + b/init/Kconfig | 62 ++++------ b/kernel/rcu/tree.c | 50 ++++++-- b/kernel/rcu/tree.h | 29 ++++ b/kernel/rcu/tree_plugin.h | 14 +- b/lib/Kconfig.debug | 1 b/tools/testing/selftests/rcutorture/configs/rcu/SRCU-N | 1 b/tools/testing/selftests/rcutorture/configs/rcu/TASKS01 | 2 b/tools/testing/selftests/rcutorture/configs/rcu/TASKS02 | 1 b/tools/testing/selftests/rcutorture/configs/rcu/TASKS03 | 1 b/tools/testing/selftests/rcutorture/configs/rcu/TREE01 | 1 b/tools/testing/selftests/rcutorture/configs/rcu/TREE02 | 2 b/tools/testing/selftests/rcutorture/configs/rcu/TREE02-T | 1 b/tools/testing/selftests/rcutorture/configs/rcu/TREE03 | 2 b/tools/testing/selftests/rcutorture/configs/rcu/TREE04 | 2 b/tools/testing/selftests/rcutorture/configs/rcu/TREE05 | 2 b/tools/testing/selftests/rcutorture/configs/rcu/TREE06 | 2 b/tools/testing/selftests/rcutorture/configs/rcu/TREE06.boot | 1 b/tools/testing/selftests/rcutorture/configs/rcu/TREE07 | 2 b/tools/testing/selftests/rcutorture/configs/rcu/TREE08 | 2 b/tools/testing/selftests/rcutorture/configs/rcu/TREE08-T | 1 b/tools/testing/selftests/rcutorture/configs/rcu/TREE08-T.boot | 1 b/tools/testing/selftests/rcutorture/configs/rcu/TREE08.boot | 1 23 files changed, 127 insertions(+), 65 deletions(-)