From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760807Ab2C3OBC (ORCPT ); Fri, 30 Mar 2012 10:01:02 -0400 Received: from terminus.zytor.com ([198.137.202.10]:46149 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760180Ab2C3OA4 (ORCPT ); Fri, 30 Mar 2012 10:00:56 -0400 Date: Fri, 30 Mar 2012 06:58:25 -0700 From: tip-bot for Martin Schwidefsky Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, schwidefsky@de.ibm.com, srivatsa.bhat@linux.vnet.ibm.com, tglx@linutronix.de, mhocko@suse.cz Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, schwidefsky@de.ibm.com, tglx@linutronix.de, srivatsa.bhat@linux.vnet.ibm.com, mhocko@suse.cz In-Reply-To: <20120330122308.18720283@de.ibm.com> References: <20120330122308.18720283@de.ibm.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:timers/core] proc: stats: Use arch_idle_time for idle and iowait times if available Git-Commit-ID: cb85a6ed67e979c59a29b7b4e8217e755b951cf4 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.6 (terminus.zytor.com [127.0.0.1]); Fri, 30 Mar 2012 06:58:31 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: cb85a6ed67e979c59a29b7b4e8217e755b951cf4 Gitweb: http://git.kernel.org/tip/cb85a6ed67e979c59a29b7b4e8217e755b951cf4 Author: Martin Schwidefsky AuthorDate: Fri, 30 Mar 2012 12:23:08 +0200 Committer: Thomas Gleixner CommitDate: Fri, 30 Mar 2012 15:43:33 +0200 proc: stats: Use arch_idle_time for idle and iowait times if available Git commit a25cac5198d4ff28 "proc: Consider NO_HZ when printing idle and iowait times" changes the code for /proc/stat to use get_cpu_idle_time_us and get_cpu_iowait_time_us if the system is running with nohz enabled. For architectures which define arch_idle_time (currently s390 only) this is a change for the worse. The result of arch_idle_time is supposed to be the exact sleep time of the target cpu and should be used instead of the value kept by the scheduler. Signed-off-by: Martin Schwidefsky Reviewed-by: Michal Hocko Reviewed-by: Srivatsa S. Bhat Link: http://lkml.kernel.org/r/20120330122308.18720283@de.ibm.com Signed-off-by: Thomas Gleixner --- fs/proc/stat.c | 34 ++++++++++++++++++++++++++++------ 1 files changed, 28 insertions(+), 6 deletions(-) diff --git a/fs/proc/stat.c b/fs/proc/stat.c index 6a0c62d..64c3b31 100644 --- a/fs/proc/stat.c +++ b/fs/proc/stat.c @@ -18,19 +18,39 @@ #ifndef arch_irq_stat #define arch_irq_stat() 0 #endif -#ifndef arch_idle_time -#define arch_idle_time(cpu) 0 -#endif + +#ifdef arch_idle_time + +static cputime64_t get_idle_time(int cpu) +{ + cputime64_t idle; + + idle = kcpustat_cpu(cpu).cpustat[CPUTIME_IDLE]; + if (cpu_online(cpu) && !nr_iowait_cpu(cpu)) + idle += arch_idle_time(cpu); + return idle; +} + +static cputime64_t get_iowait_time(int cpu) +{ + cputime64_t iowait; + + iowait = kcpustat_cpu(cpu).cpustat[CPUTIME_IOWAIT]; + if (cpu_online(cpu) && nr_iowait_cpu(cpu)) + iowait += arch_idle_time(cpu); + return iowait; +} + +#else static u64 get_idle_time(int cpu) { u64 idle, idle_time = get_cpu_idle_time_us(cpu, NULL); - if (idle_time == -1ULL) { + if (idle_time == -1ULL) /* !NO_HZ so we can rely on cpustat.idle */ idle = kcpustat_cpu(cpu).cpustat[CPUTIME_IDLE]; - idle += arch_idle_time(cpu); - } else + else idle = usecs_to_cputime64(idle_time); return idle; @@ -49,6 +69,8 @@ static u64 get_iowait_time(int cpu) return iowait; } +#endif + static int show_stat(struct seq_file *p, void *v) { int i, j;