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From: Frederic Weisbecker <fweisbec@gmail.com>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
	Ingo Molnar <mingo@kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Peter Zijlstra <peterz@infradead.org>,
	Borislav Petkov <bp@alien8.de>,
	Li Zhong <zhong@linux.vnet.ibm.com>,
	Mike Galbraith <efault@gmx.de>, Kevin Hilman <khilman@linaro.org>
Subject: [PATCH 17/18] vtime: Always scale generic vtime accounting results
Date: Wed, 17 Jul 2013 18:44:30 +0200	[thread overview]
Message-ID: <1374079471-3129-18-git-send-email-fweisbec@gmail.com> (raw)
In-Reply-To: <1374079471-3129-1-git-send-email-fweisbec@gmail.com>

The cputime accounting in full dynticks can be a subtle
mixup of CPUs using tick based accounting and others using
generic vtime.

As long as the tick can have a share on producing these stats, we
want to scale the result against CFS precise accounting as the tick
can miss some task hiding between the periodic interrupt.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>
---
 kernel/sched/cputime.c |    6 ------
 1 files changed, 0 insertions(+), 6 deletions(-)

diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index 0831b06..e9e742e 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -553,12 +553,6 @@ static void cputime_adjust(struct task_cputime *curr,
 {
 	cputime_t rtime, stime, utime, total;
 
-	if (vtime_accounting_enabled()) {
-		*ut = curr->utime;
-		*st = curr->stime;
-		return;
-	}
-
 	stime = curr->stime;
 	total = stime + curr->utime;
 
-- 
1.7.5.4


  parent reply	other threads:[~2013-07-17 16:45 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-07-17 16:44 [PATCH 00/18] nohz patches for 3.12 preview Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 01/18] nohz: Do not warn about unstable tsc unless user uses nohz_full Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 02/18] nohz: fix compile warning in tick_nohz_init() Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 03/18] sched: Consolidate open coded preemptible() checks Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 04/18] context_tracing: Fix guest accounting with native vtime Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 05/18] vtime: Update a few comments Frederic Weisbecker
2013-07-17 17:57   ` Steven Rostedt
2013-07-18 21:30     ` Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 06/18] context_tracking: Fix runtime CPU off-case Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 07/18] nohz: Selectively enable context tracking on full dynticks CPUs Frederic Weisbecker
2013-07-17 18:27   ` Steven Rostedt
2013-07-18 22:13     ` Frederic Weisbecker
2013-07-18 22:51       ` Steven Rostedt
2013-07-19 14:19         ` Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 08/18] context_tracking: Ground setup for static key use Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 09/18] context_tracking: Optimize main APIs off case with static key Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 10/18] context_tracking: Optimize context switch off case with static keys Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 11/18] context_tracking: User/kernel broundary cross trace events Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 12/18] vtime: Remove a few unneeded generic vtime state checks Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 13/18] vtime: Fix racy cputime delta update Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 14/18] context_tracking: Split low level state headers Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 15/18] vtime: Describe overriden functions in dedicated arch headers Frederic Weisbecker
2013-07-17 16:44 ` [PATCH 16/18] vtime: Optimize full dynticks accounting off case with static keys Frederic Weisbecker
2013-07-17 16:44 ` Frederic Weisbecker [this message]
2013-07-17 16:44 ` [PATCH 18/18] vtime: Always debug check snapshot source _before_ updating it Frederic Weisbecker

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