public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: tip-bot for Frederic Weisbecker <fweisbec@gmail.com>
To: linux-tip-commits@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com,
	a.p.zijlstra@chello.nl, john.stultz@linaro.org,
	fweisbec@gmail.com, tglx@linutronix.de, yong.zhang0@gmail.com,
	mingo@elte.hu
Subject: [tip:timers/core] nohz: Remove ts-> Einidle checks before restarting the tick
Date: Wed, 15 Feb 2012 11:38:29 -0800	[thread overview]
Message-ID: <tip-15f827be93928890bba965bc175caee50c4406d2@git.kernel.org> (raw)
In-Reply-To: <1327427984-23282-2-git-send-email-fweisbec@gmail.com>

Commit-ID:  15f827be93928890bba965bc175caee50c4406d2
Gitweb:     http://git.kernel.org/tip/15f827be93928890bba965bc175caee50c4406d2
Author:     Frederic Weisbecker <fweisbec@gmail.com>
AuthorDate: Tue, 24 Jan 2012 18:59:43 +0100
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Wed, 15 Feb 2012 15:23:09 +0100

nohz: Remove ts->Einidle checks before restarting the tick

ts->inidle is set by tick_nohz_idle_enter() and unset by
tick_nohz_idle_exit(). However these two calls are assumed
to be always paired. This means that by the time we call
tick_nohz_idle_exit(), ts->inidle is supposed to be always
set to 1.

Remove the checks for ts->inidle in tick_nohz_idle_exit().
This simplifies a bit the code and improves its debuggability
(ie: ensure the call is paired with a tick_nohz_idle_enter()
call).

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Reviewed-by: Yong Zhang <yong.zhang0@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Ingo Molnar <mingo@elte.hu>
Link: http://lkml.kernel.org/r/1327427984-23282-2-git-send-email-fweisbec@gmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 kernel/time/tick-sched.c |   11 ++++++-----
 1 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 8cfffd9..3526038 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -558,20 +558,21 @@ void tick_nohz_idle_exit(void)
 
 	local_irq_disable();
 
-	if (ts->idle_active || (ts->inidle && ts->tick_stopped))
+	WARN_ON_ONCE(!ts->inidle);
+
+	ts->inidle = 0;
+
+	if (ts->idle_active || ts->tick_stopped)
 		now = ktime_get();
 
 	if (ts->idle_active)
 		tick_nohz_stop_idle(cpu, now);
 
-	if (!ts->inidle || !ts->tick_stopped) {
-		ts->inidle = 0;
+	if (!ts->tick_stopped) {
 		local_irq_enable();
 		return;
 	}
 
-	ts->inidle = 0;
-
 	/* Update jiffies first */
 	select_nohz_load_balancer(0);
 	tick_do_update_jiffies64(now);

  reply	other threads:[~2012-02-15 19:39 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-01-24 17:59 [PATCH 1/3] nohz: Remove update_ts_time_stat from tick_nohz_start_idle Frederic Weisbecker
2012-01-24 17:59 ` [PATCH 2/3] nohz: Remove ts->inidle checks before restarting the tick Frederic Weisbecker
2012-02-15 19:38   ` tip-bot for Frederic Weisbecker [this message]
2012-01-24 17:59 ` [PATCH 3/3] timer: Fix bad idle check on irq entry Frederic Weisbecker
2012-02-15 19:39   ` [tip:timers/core] " tip-bot for Frederic Weisbecker

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=tip-15f827be93928890bba965bc175caee50c4406d2@git.kernel.org \
    --to=fweisbec@gmail.com \
    --cc=a.p.zijlstra@chello.nl \
    --cc=hpa@zytor.com \
    --cc=john.stultz@linaro.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-tip-commits@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=mingo@redhat.com \
    --cc=tglx@linutronix.de \
    --cc=yong.zhang0@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox