From patchwork Fri Jun 5 19:05:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chen Yu X-Patchwork-Id: 11590419 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id BD9A3618 for ; Fri, 5 Jun 2020 19:04:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ADDF42077D for ; Fri, 5 Jun 2020 19:04:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727888AbgFETE7 (ORCPT ); Fri, 5 Jun 2020 15:04:59 -0400 Received: from mga12.intel.com ([192.55.52.136]:12924 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726958AbgFETE7 (ORCPT ); Fri, 5 Jun 2020 15:04:59 -0400 IronPort-SDR: /8QlvB6ZhTf5XF37AYd1aCtLm3c8IfOVmUtr5JQks5z76GKlnZtuFDTtrPAJCBUH7nQMOlbQi0 i+mKMA+3SYGQ== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jun 2020 12:04:56 -0700 IronPort-SDR: so7DLzq1yp6BvnF8hi/wQpHSwI9mxUiGmwxwaZxc+/8kX6NPxrmAl9DSAi+Bs1TmGoUhfFt2S5 NH6vdXfBLFwg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,477,1583222400"; d="scan'208";a="417372231" Received: from chenyu-office.sh.intel.com ([10.239.158.173]) by orsmga004.jf.intel.com with ESMTP; 05 Jun 2020 12:04:54 -0700 From: Chen Yu To: "Rafael J . Wysocki" , Len Brown , Greg Kroah-Hartman , Michal Miroslaw Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Chen Yu Subject: [PATCH 2/2][RFC] PM-runtime: add tracepoints to cover all usage_count changes Date: Sat, 6 Jun 2020 03:05:52 +0800 Message-Id: <6ce5c2d21758363b7c9a31187eda1787bc4a6160.1591380524.git.yu.c.chen@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: References: Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Commit d229290689ae ("PM-runtime: add tracepoints for usage_count changes") has added some tracepoints to monitor the change of runtime usage, and there is something to improve: 1. There are some places that adjust the usage count have not been traced yet. For example, pm_runtime_get_noresume() and pm_runtime_put_noidle() 2. The change of the usage count will not be tracked if decreased from 1 to 0. This patch address above issues by tracking the usage count whenever it has been modified. And these changes has helped track down the e1000e runtime issue. Signed-off-by: Chen Yu --- drivers/base/power/runtime.c | 37 ++++++++++++++++++++++-------------- 1 file changed, 23 insertions(+), 14 deletions(-) diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c index 85a248e196ca..4aa2b5aa0bb8 100644 --- a/drivers/base/power/runtime.c +++ b/drivers/base/power/runtime.c @@ -1004,10 +1004,11 @@ int __pm_runtime_idle(struct device *dev, int rpmflags) int retval; if (rpmflags & RPM_GET_PUT) { - if (!atomic_dec_and_test(&dev->power.usage_count)) { - trace_rpm_usage_rcuidle(dev, rpmflags); + bool non_zero = !atomic_dec_and_test(&dev->power.usage_count); + + trace_rpm_usage_rcuidle(dev, rpmflags); + if (non_zero) return 0; - } } might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); @@ -1038,10 +1039,12 @@ int __pm_runtime_suspend(struct device *dev, int rpmflags) int retval; if (rpmflags & RPM_GET_PUT) { - if (!atomic_dec_and_test(&dev->power.usage_count)) { - trace_rpm_usage_rcuidle(dev, rpmflags); + bool non_zero = !atomic_dec_and_test(&dev->power.usage_count); + + trace_rpm_usage_rcuidle(dev, rpmflags); + if (non_zero) return 0; - } + } might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe); @@ -1073,8 +1076,10 @@ int __pm_runtime_resume(struct device *dev, int rpmflags) might_sleep_if(!(rpmflags & RPM_ASYNC) && !dev->power.irq_safe && dev->power.runtime_status != RPM_ACTIVE); - if (rpmflags & RPM_GET_PUT) + if (rpmflags & RPM_GET_PUT) { atomic_inc(&dev->power.usage_count); + trace_rpm_usage_rcuidle(dev, rpmflags); + } spin_lock_irqsave(&dev->power.lock, flags); retval = rpm_resume(dev, rpmflags); @@ -1448,16 +1453,17 @@ EXPORT_SYMBOL_GPL(pm_runtime_forbid); */ void pm_runtime_allow(struct device *dev) { + bool is_zero; + spin_lock_irq(&dev->power.lock); if (dev->power.runtime_auto) goto out; dev->power.runtime_auto = true; - if (atomic_dec_and_test(&dev->power.usage_count)) + is_zero = atomic_dec_and_test(&dev->power.usage_count); + trace_rpm_usage_rcuidle(dev, RPM_AUTO | RPM_ASYNC); + if (is_zero) rpm_idle(dev, RPM_AUTO | RPM_ASYNC); - else - trace_rpm_usage_rcuidle(dev, RPM_AUTO | RPM_ASYNC); - out: spin_unlock_irq(&dev->power.lock); } @@ -1523,9 +1529,8 @@ static void update_autosuspend(struct device *dev, int old_delay, int old_use) /* If it used to be allowed then prevent it. */ if (!old_use || old_delay >= 0) { atomic_inc(&dev->power.usage_count); - rpm_resume(dev, 0); - } else { trace_rpm_usage_rcuidle(dev, 0); + rpm_resume(dev, 0); } } @@ -1533,8 +1538,10 @@ static void update_autosuspend(struct device *dev, int old_delay, int old_use) else { /* If it used to be prevented then allow it. */ - if (old_use && old_delay < 0) + if (old_use && old_delay < 0) { atomic_dec(&dev->power.usage_count); + trace_rpm_usage_rcuidle(dev, 0); + } /* Maybe we can autosuspend now. */ rpm_idle(dev, RPM_AUTO); @@ -1741,12 +1748,14 @@ void pm_runtime_drop_link(struct device *dev) void pm_runtime_get_noresume(struct device *dev) { atomic_inc(&dev->power.usage_count); + trace_rpm_usage_rcuidle(dev, 0); } EXPORT_SYMBOL_GPL(pm_runtime_get_noresume); void pm_runtime_put_noidle(struct device *dev) { atomic_add_unless(&dev->power.usage_count, -1, 0); + trace_rpm_usage_rcuidle(dev, 0); } EXPORT_SYMBOL_GPL(pm_runtime_put_noidle);