From patchwork Tue Apr 26 21:04:07 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Paul E. McKenney" X-Patchwork-Id: 8945741 Return-Path: X-Original-To: patchwork-linux-omap@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id F2D64BF29F for ; Tue, 26 Apr 2016 21:11:05 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id F35E92014A for ; Tue, 26 Apr 2016 21:11:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D215A2012B for ; Tue, 26 Apr 2016 21:11:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752893AbcDZVKE (ORCPT ); Tue, 26 Apr 2016 17:10:04 -0400 Received: from e34.co.us.ibm.com ([32.97.110.152]:43775 "EHLO e34.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752348AbcDZVKC (ORCPT ); Tue, 26 Apr 2016 17:10:02 -0400 Received: from localhost by e34.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Tue, 26 Apr 2016 15:09:40 -0600 X-IBM-Helo: d03dlp02.boulder.ibm.com X-IBM-MailFrom: paulmck@linux.vnet.ibm.com X-IBM-RcptTo: linux-kernel@vger.kernel.org;linux-omap@vger.kernel.org Received: from b01cxnp22034.gho.pok.ibm.com (b01cxnp22034.gho.pok.ibm.com [9.57.198.24]) by d03dlp02.boulder.ibm.com (Postfix) with ESMTP id CE4DF3E40D47; Tue, 26 Apr 2016 15:03:31 -0600 (MDT) Received: from d01av01.pok.ibm.com (d01av01.pok.ibm.com [9.56.224.215]) by b01cxnp22034.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u3QL3VCS18809074; Tue, 26 Apr 2016 21:03:31 GMT Received: from d01av01.pok.ibm.com (localhost [127.0.0.1]) by d01av01.pok.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id u3QL3U3g007404; Tue, 26 Apr 2016 17:03:31 -0400 Received: from paulmck-ThinkPad-W541 ([9.70.82.191]) by d01av01.pok.ibm.com (8.14.4/8.14.4/NCO v10.0 AVin) with ESMTP id u3QL3Tfx007329; Tue, 26 Apr 2016 17:03:29 -0400 Received: by paulmck-ThinkPad-W541 (Postfix, from userid 1000) id A8CB416C1186; Tue, 26 Apr 2016 14:04:07 -0700 (PDT) Date: Tue, 26 Apr 2016 14:04:07 -0700 From: "Paul E. McKenney" To: Tony Lindgren Cc: Steven Rostedt , linux-kernel@vger.kernel.org, mingo@kernel.org, Russell King , linux-omap@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH arm 1/1] arm: Use _rcuidle tracepoint to allow use from idle Message-ID: <20160426210407.GT3715@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <20160426182939.GO5995@atomide.com> <20160426190755.GK3715@linux.vnet.ibm.com> <20160426193949.GP5995@atomide.com> <20160426154414.7bb33de4@gandalf.local.home> <20160426195158.GR5995@atomide.com> <20160426200613.GO3715@linux.vnet.ibm.com> <20160426201134.GA29779@linux.vnet.ibm.com> <20160426202538.GS5995@atomide.com> <20160426204148.GR3715@linux.vnet.ibm.com> <20160426204613.GT5995@atomide.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20160426204613.GT5995@atomide.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16042621-0017-0000-0000-000029911865 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org X-Spam-Status: No, score=-7.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP On Tue, Apr 26, 2016 at 01:46:15PM -0700, Tony Lindgren wrote: > * Paul E. McKenney [160426 13:42]: > > On Tue, Apr 26, 2016 at 01:25:39PM -0700, Tony Lindgren wrote: > > > * Paul E. McKenney [160426 13:12]: > > > > On Tue, Apr 26, 2016 at 01:06:13PM -0700, Paul E. McKenney wrote: > > > > > On Tue, Apr 26, 2016 at 12:51:59PM -0700, Tony Lindgren wrote: > > > > > > * Steven Rostedt [160426 12:45]: > > > > > > > *Whack* *Whack* *Whack*!!! > > > > > > > > > > > > > > Signed-off-by: Steven Rostedt > > > > > > > --- > > > > > > > diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c > > > > > > > index fb74dc1f7520..4fa43c02d682 100644 > > > > > > > --- a/drivers/clk/clk.c > > > > > > > +++ b/drivers/clk/clk.c > > > > > > > @@ -682,12 +682,12 @@ static void clk_core_disable(struct clk_core *core) > > > > > > > if (--core->enable_count > 0) > > > > > > > return; > > > > > > > > > > > > > > - trace_clk_disable(core); > > > > > > > + trace_clk_disable_rcuidle(core); > > > > > > > > > > > > > > if (core->ops->disable) > > > > > > > core->ops->disable(core->hw); > > > > > > > > > > > > > > - trace_clk_disable_complete(core); > > > > > > > + trace_clk_disable_complete_rcuidle(core); > > > > > > > > > > > > > > clk_core_disable(core->parent); > > > > > > > } > > > > > > > > > > > > Now the mole shows up here! > > > > > > > > > > And the patch shows up here! > > > > > > > > And I bet you will need this one as well... > > > > > > OK and now the mode is coming back after a short nap during idle: > > > > Seems a bit unfair to whack it just after a short nap, but here goes! > > This mode seems pretty hard headed :) Now clk_core_enable: Nah, just a lot of heads... Thanx, Paul ------------------------------------------------------------------------ commit 21c3fc2373886a9fa014f0f69a72186377758f4b Author: Paul E. McKenney Date: Tue Apr 26 14:02:23 2016 -0700 arm: Whack an expected event-trace-from-idle mole This commit fixes the RCU use-from-idle bug corresponding the following splat: > [ INFO: suspicious RCU usage. ] > 4.6.0-rc5-next-20160426+ #1127 Not tainted > ------------------------------- > include/trace/events/clk.h:45 suspicious rcu_dereference_check() usage! > > other info that might help us debug this: > > > RCU used illegally from idle CPU! > rcu_scheduler_active = 1, debug_locks = 0 > RCU used illegally from extended quiescent state! > 2 locks held by swapper/0/0: > #0: (&oh->hwmod_key#30){......}, at: [] omap_hwmod_enable+0x18/0x44 > #1: (enable_lock){......}, at: [] clk_enable_lock+0x18/0x124 > > stack backtrace: > CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1127 > Hardware name: Generic OMAP36xx (Flattened Device Tree) > [] (unwind_backtrace) from [] (show_stack+0x10/0x14) > [] (show_stack) from [] (dump_stack+0xb0/0xe4) > [] (dump_stack) from [] (clk_core_enable+0x1e0/0x36c) > [] (clk_core_enable) from [] (clk_enable+0x1c/0x38) > [] (clk_enable) from [] (_enable_clocks+0x18/0x7c) > [] (_enable_clocks) from [] (_enable+0x114/0x2ec) > [] (_enable) from [] (omap_hwmod_enable+0x24/0x44) > [] (omap_hwmod_enable) from [] (omap_device_enable+0x3c/0x90) > [] (omap_device_enable) from [] (_od_runtime_resume+0x10/0x38) > [] (_od_runtime_resume) from [] (__rpm_callback+0x2c/0x60) > [] (__rpm_callback) from [] (rpm_callback+0x20/0x80) > [] (rpm_callback) from [] (rpm_resume+0x3d0/0x6f0) > [] (rpm_resume) from [] (__pm_runtime_resume+0x4c/0x64) > [] (__pm_runtime_resume) from [] (omap2_gpio_resume_after_idle+0x54/0x68) > [] (omap2_gpio_resume_after_idle) from [] (omap3_enter_idle_bm+0xfc/0x1ec) > [] (omap3_enter_idle_bm) from [] (cpuidle_enter_state+0x80/0x3d4) > [] (cpuidle_enter_state) from [] (cpu_startup_entry+0x198/0x3a0) > [] (cpu_startup_entry) from [] (start_kernel+0x354/0x3c8) > [] (start_kernel) from [<8000807c>] (0x8000807c) Reported-by: Tony Lindgren Signed-off-by: Paul E. McKenney Cc: Tony Lindgren Cc: Russell King Cc: Steven Rostedt Cc: Cc: Tested-by: Tony Lindgren --- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c index 4fa43c02d682..ec83f404c1d2 100644 --- a/drivers/clk/clk.c +++ b/drivers/clk/clk.c @@ -735,12 +735,12 @@ static int clk_core_enable(struct clk_core *core) if (ret) return ret; - trace_clk_enable(core); + trace_clk_enable_rcuidle(core); if (core->ops->enable) ret = core->ops->enable(core->hw); - trace_clk_enable_complete(core); + trace_clk_enable_complete_rcuidle(core); if (ret) { clk_core_disable(core->parent);