From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ACFB3C43381 for ; Wed, 20 Feb 2019 16:19:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 79A9A20880 for ; Wed, 20 Feb 2019 16:19:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727213AbfBTQTd (ORCPT ); Wed, 20 Feb 2019 11:19:33 -0500 Received: from [101.13.169.104] ([101.13.169.104]:54497 "EHLO E6440.gar.corp.intel.com" rhost-flags-FAIL-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1725877AbfBTQTc (ORCPT ); Wed, 20 Feb 2019 11:19:32 -0500 Received: from E6440.gar.corp.intel.com (localhost [127.0.0.1]) by E6440.gar.corp.intel.com (Postfix) with ESMTP id 4E1ACC0500; Thu, 21 Feb 2019 00:12:25 +0800 (CST) From: Harry Pan To: LKML Cc: gs0622@gmail.com, Harry Pan , rjw@rjwysocki.net, len.brown@intel.com, pavel@ucw.cz, linux-pm@vger.kernel.org Subject: [PATCH v4] PM / suspend: measure the time of filesystem syncing Date: Thu, 21 Feb 2019 00:12:22 +0800 Message-Id: <20190220161222.632-1-harry.pan@intel.com> X-Mailer: git-send-email 2.18.1 In-Reply-To: <20190214111543.22137-1-harry.pan@intel.com> References: <20190214111543.22137-1-harry.pan@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch gives the reader an intuitive metric of the time cost by the kernel issuing a filesystem sync during suspend; although developer can guess by the timestamp of next log or enable the ftrace power event for manual calculation, this manner is easier to read and benefits the automatic script. v2: simplify the variables, apply the simplest form of ktime API. v3: reduce conditional compilation, rectify profiling in better syntax v4: avoid interposition, profile on hibernation, rectify printk format Signed-off-by: Harry Pan --- kernel/power/hibernate.c | 9 +++++++-- kernel/power/suspend.c | 20 +++++++++++++------- 2 files changed, 20 insertions(+), 9 deletions(-) diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index abef759de7c8..387703907827 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -688,6 +688,8 @@ int hibernate(void) { int error, nr_calls = 0; bool snapshot_test = false; + ktime_t start; + s64 elapsed_msecs; if (!hibernation_available()) { pm_pr_dbg("Hibernation not available.\n"); @@ -709,9 +711,12 @@ int hibernate(void) goto Exit; } - pr_info("Syncing filesystems ... \n"); + start = ktime_get(); ksys_sync(); - pr_info("done.\n"); + elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start)); + pr_info("Filesystems sync: %lld.%03lld seconds\n", + elapsed_msecs / MSEC_PER_SEC, + elapsed_msecs % MSEC_PER_SEC); error = freeze_processes(); if (error) diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 0bd595a0b610..7fb5ba1314d3 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -568,13 +568,19 @@ static int enter_state(suspend_state_t state) if (state == PM_SUSPEND_TO_IDLE) s2idle_begin(); -#ifndef CONFIG_SUSPEND_SKIP_SYNC - trace_suspend_resume(TPS("sync_filesystems"), 0, true); - pr_info("Syncing filesystems ... "); - ksys_sync(); - pr_cont("done.\n"); - trace_suspend_resume(TPS("sync_filesystems"), 0, false); -#endif + if (!IS_ENABLED(CONFIG_SUSPEND_SKIP_SYNC)) { + ktime_t start; + s64 elapsed_msecs; + + trace_suspend_resume(TPS("sync_filesystems"), 0, true); + start = ktime_get(); + ksys_sync(); + elapsed_msecs = ktime_to_ms(ktime_sub(ktime_get(), start)); + pr_info("Filesystems sync: %lld.%03lld seconds\n", + elapsed_msecs / MSEC_PER_SEC, + elapsed_msecs % MSEC_PER_SEC); + trace_suspend_resume(TPS("sync_filesystems"), 0, false); + } pm_pr_dbg("Preparing system for sleep (%s)\n", mem_sleep_labels[state]); pm_suspend_clear_flags(); -- 2.18.1