From patchwork Fri Sep 21 18:59:58 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Walmsley X-Patchwork-Id: 1492961 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) by patchwork1.kernel.org (Postfix) with ESMTP id 37D653FCFC for ; Fri, 21 Sep 2012 19:01:41 +0000 (UTC) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TF8SJ-0001cS-Kj; Fri, 21 Sep 2012 19:00:03 +0000 Received: from utopia.booyaka.com ([74.50.51.50]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1TF8SG-0001bN-57 for linux-arm-kernel@lists.infradead.org; Fri, 21 Sep 2012 19:00:00 +0000 Received: (qmail 16999 invoked by uid 1019); 21 Sep 2012 18:59:58 -0000 Date: Fri, 21 Sep 2012 18:59:58 +0000 (UTC) From: Paul Walmsley To: "Paul E. McKenney" Subject: Re: rcu self-detected stall messages on OMAP3, 4 boards In-Reply-To: Message-ID: References: <20120913011208.GT4257@linux.vnet.ibm.com> <20120920000351.GI2455@linux.vnet.ibm.com> <20120920220130.GN2449@linux.vnet.ibm.com> <20120920232114.GO2449@linux.vnet.ibm.com> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 X-Spam-Note: CRM114 invocation failed X-Spam-Score: -1.9 (-) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (-1.9 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 SPF_HELO_PASS SPF: HELO matches SPF record -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] 0.0 UPPERCASE_50_75 message body is 50-75% uppercase Cc: "Hilman, Kevin" , "" , fweisbec@gmail.com, "Bruce, Becky" , "" , "Paul E. McKenney" , "Shilimkar, Santosh" , "Hunter, Jon" , "" , "" X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-arm-kernel-bounces@lists.infradead.org Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org Hi Just did a test with CONFIG_NO_HZ=n, and no rcu_sched stall messages appeared for 60 minutes. Following is the diff from omap2plus_defconfig. - Paul --- .config 2012-09-21 12:51:19.114938954 -0600 +++ .testconfig 2012-09-21 12:51:15.686926318 -0600 @@ -69,7 +69,7 @@ # Timers subsystem # CONFIG_TICK_ONESHOT=y -CONFIG_NO_HZ=y +# CONFIG_NO_HZ is not set CONFIG_HIGH_RES_TIMERS=y # @@ -80,7 +80,6 @@ CONFIG_RCU_FANOUT=32 CONFIG_RCU_FANOUT_LEAF=16 # CONFIG_RCU_FANOUT_EXACT is not set -# CONFIG_RCU_FAST_NO_HZ is not set # CONFIG_TREE_RCU_TRACE is not set CONFIG_IKCONFIG=y CONFIG_IKCONFIG_PROC=y @@ -2535,7 +2534,7 @@ # CONFIG_BOOT_PRINTK_DELAY is not set # CONFIG_RCU_TORTURE_TEST is not set CONFIG_RCU_CPU_STALL_TIMEOUT=60 -# CONFIG_RCU_CPU_STALL_INFO is not set +CONFIG_RCU_CPU_STALL_INFO=y # CONFIG_RCU_TRACE is not set # CONFIG_KPROBES_SANITY_TEST is not set # CONFIG_BACKTRACE_SELF_TEST is not set