From patchwork Tue Sep 6 18:00:05 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Paul E. McKenney" X-Patchwork-Id: 3906 Return-Path: X-Original-To: patchwork@peony.canonical.com Delivered-To: patchwork@peony.canonical.com Received: from fiordland.canonical.com (fiordland.canonical.com [91.189.94.145]) by peony.canonical.com (Postfix) with ESMTP id E206B23FBE for ; Wed, 7 Sep 2011 06:20:51 +0000 (UTC) Received: from mail-fx0-f52.google.com (mail-fx0-f52.google.com [209.85.161.52]) by fiordland.canonical.com (Postfix) with ESMTP id D6670A181E3 for ; Wed, 7 Sep 2011 06:20:51 +0000 (UTC) Received: by mail-fx0-f52.google.com with SMTP id 18so398726fxd.11 for ; Tue, 06 Sep 2011 23:20:51 -0700 (PDT) Received: by 10.223.4.133 with SMTP id 5mr3104306far.81.1315376451784; Tue, 06 Sep 2011 23:20:51 -0700 (PDT) X-Forwarded-To: linaro-patchwork@canonical.com X-Forwarded-For: patch@linaro.org linaro-patchwork@canonical.com Delivered-To: patches@linaro.org Received: by 10.152.11.8 with SMTP id m8cs127773lab; Tue, 6 Sep 2011 23:20:51 -0700 (PDT) Received: by 10.91.3.26 with SMTP id f26mr4383346agi.59.1315376450518; Tue, 06 Sep 2011 23:20:50 -0700 (PDT) Received: from e6.ny.us.ibm.com (e6.ny.us.ibm.com [32.97.182.146]) by mx.google.com with ESMTPS id g32si5489519anp.109.2011.09.06.23.20.49 (version=TLSv1/SSLv3 cipher=OTHER); Tue, 06 Sep 2011 23:20:49 -0700 (PDT) Received-SPF: pass (google.com: domain of paulmck@linux.vnet.ibm.com designates 32.97.182.146 as permitted sender) client-ip=32.97.182.146; Authentication-Results: mx.google.com; spf=pass (google.com: domain of paulmck@linux.vnet.ibm.com designates 32.97.182.146 as permitted sender) smtp.mail=paulmck@linux.vnet.ibm.com Received: from d01relay03.pok.ibm.com (d01relay03.pok.ibm.com [9.56.227.235]) by e6.ny.us.ibm.com (8.14.4/8.13.1) with ESMTP id p875ucUY016554 for ; Wed, 7 Sep 2011 01:56:38 -0400 Received: from d01av01.pok.ibm.com (d01av01.pok.ibm.com [9.56.224.215]) by d01relay03.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p876Kl9i240658 for ; Wed, 7 Sep 2011 02:20:48 -0400 Received: from d01av01.pok.ibm.com (loopback [127.0.0.1]) by d01av01.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p876KhOD005288 for ; Wed, 7 Sep 2011 02:20:47 -0400 Received: from paulmck-ThinkPad-W500 (dyn9050016039.mts.ibm.com [9.50.16.39] (may be forged)) by d01av01.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id p876KWUQ004397; Wed, 7 Sep 2011 02:20:42 -0400 Received: by paulmck-ThinkPad-W500 (Postfix, from userid 1000) id A8A5613F873; Tue, 6 Sep 2011 11:00:51 -0700 (PDT) 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, patches@linaro.org, "Paul E. McKenney" Subject: [PATCH tip/core/rcu 11/55] rcu: Drive configuration directly from SMP and PREEMPT Date: Tue, 6 Sep 2011 11:00:05 -0700 Message-Id: <1315332049-2604-11-git-send-email-paulmck@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.3.2 In-Reply-To: <20110906180015.GA2560@linux.vnet.ibm.com> References: <20110906180015.GA2560@linux.vnet.ibm.com> This commit eliminates the possibility of running TREE_PREEMPT_RCU when SMP=n and of running TINY_RCU when PREEMPT=y. People who really want these combinations can hand-edit init/Kconfig, but eliminating them as choices for production systems reduces the amount of testing required. It will also allow cutting out a few #ifdefs. Note that running TREE_RCU and TINY_RCU on single-CPU systems using SMP-built kernels is still supported. Signed-off-by: Paul E. McKenney --- init/Kconfig | 6 +++--- 1 files changed, 3 insertions(+), 3 deletions(-) diff --git a/init/Kconfig b/init/Kconfig index 412c21b..e22a691 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -391,7 +391,7 @@ config TREE_RCU config TREE_PREEMPT_RCU bool "Preemptible tree-based hierarchical RCU" - depends on PREEMPT + depends on PREEMPT && SMP help This option selects the RCU implementation that is designed for very large SMP systems with hundreds or @@ -401,7 +401,7 @@ config TREE_PREEMPT_RCU config TINY_RCU bool "UP-only small-memory-footprint RCU" - depends on !SMP + depends on !PREEMPT && !SMP help This option selects the RCU implementation that is designed for UP systems from which real-time response @@ -410,7 +410,7 @@ config TINY_RCU config TINY_PREEMPT_RCU bool "Preemptible UP-only small-memory-footprint RCU" - depends on !SMP && PREEMPT + depends on PREEMPT && !SMP help This option selects the RCU implementation that is designed for real-time UP systems. This option greatly reduces the