From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755080AbcCULS1 (ORCPT ); Mon, 21 Mar 2016 07:18:27 -0400 Received: from terminus.zytor.com ([198.137.202.10]:49654 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754243AbcCULSR (ORCPT ); Mon, 21 Mar 2016 07:18:17 -0400 Date: Mon, 21 Mar 2016 04:17:44 -0700 From: tip-bot for Zhao Lei Message-ID: Cc: htejun@gmail.com, hpa@zytor.com, tglx@linutronix.de, linux-kernel@vger.kernel.org, mingo@kernel.org, torvalds@linux-foundation.org, peterz@infradead.org, zhaolei@cn.fujitsu.com Reply-To: zhaolei@cn.fujitsu.com, torvalds@linux-foundation.org, peterz@infradead.org, mingo@kernel.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, hpa@zytor.com, htejun@gmail.com In-Reply-To: References: To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/urgent] sched/cpuacct: Simplify the cpuacct code Git-Commit-ID: 73e6aafd9ea81498d31361f01db84a0118da2d1c 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 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 73e6aafd9ea81498d31361f01db84a0118da2d1c Gitweb: http://git.kernel.org/tip/73e6aafd9ea81498d31361f01db84a0118da2d1c Author: Zhao Lei AuthorDate: Thu, 17 Mar 2016 12:19:43 +0800 Committer: Ingo Molnar CommitDate: Mon, 21 Mar 2016 11:00:28 +0100 sched/cpuacct: Simplify the cpuacct code - Use for() instead of while() loop in some functions to make the code simpler. - Use this_cpu_ptr() instead of per_cpu_ptr() to make the code cleaner and a bit faster. Suggested-by: Peter Zijlstra Signed-off-by: Zhao Lei Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Tejun Heo Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/d8a7ef9592f55224630cb26dea239f05b6398a4e.1458187654.git.zhaolei@cn.fujitsu.com Signed-off-by: Ingo Molnar --- kernel/sched/cpuacct.c | 28 +++++----------------------- kernel/sched/cpuacct.h | 4 ++-- 2 files changed, 7 insertions(+), 25 deletions(-) diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c index 9c2bbf7..434c2fa 100644 --- a/kernel/sched/cpuacct.c +++ b/kernel/sched/cpuacct.c @@ -238,23 +238,10 @@ static struct cftype files[] = { void cpuacct_charge(struct task_struct *tsk, u64 cputime) { struct cpuacct *ca; - int cpu; - - cpu = task_cpu(tsk); rcu_read_lock(); - - ca = task_ca(tsk); - - while (true) { - u64 *cpuusage = per_cpu_ptr(ca->cpuusage, cpu); - *cpuusage += cputime; - - ca = parent_ca(ca); - if (!ca) - break; - } - + for (ca = task_ca(tsk); ca; ca = parent_ca(ca)) + *this_cpu_ptr(ca->cpuusage) += cputime; rcu_read_unlock(); } @@ -263,18 +250,13 @@ void cpuacct_charge(struct task_struct *tsk, u64 cputime) * * Note: it's the caller that updates the account of the root cgroup. */ -void cpuacct_account_field(struct task_struct *p, int index, u64 val) +void cpuacct_account_field(struct task_struct *tsk, int index, u64 val) { - struct kernel_cpustat *kcpustat; struct cpuacct *ca; rcu_read_lock(); - ca = task_ca(p); - while (ca != &root_cpuacct) { - kcpustat = this_cpu_ptr(ca->cpustat); - kcpustat->cpustat[index] += val; - ca = parent_ca(ca); - } + for (ca = task_ca(tsk); ca != &root_cpuacct; ca = parent_ca(ca)) + this_cpu_ptr(ca->cpustat)->cpustat[index] += val; rcu_read_unlock(); } diff --git a/kernel/sched/cpuacct.h b/kernel/sched/cpuacct.h index ed60562..ba72807 100644 --- a/kernel/sched/cpuacct.h +++ b/kernel/sched/cpuacct.h @@ -1,7 +1,7 @@ #ifdef CONFIG_CGROUP_CPUACCT extern void cpuacct_charge(struct task_struct *tsk, u64 cputime); -extern void cpuacct_account_field(struct task_struct *p, int index, u64 val); +extern void cpuacct_account_field(struct task_struct *tsk, int index, u64 val); #else @@ -10,7 +10,7 @@ static inline void cpuacct_charge(struct task_struct *tsk, u64 cputime) } static inline void -cpuacct_account_field(struct task_struct *p, int index, u64 val) +cpuacct_account_field(struct task_struct *tsk, int index, u64 val) { }