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From: Juri Lelli <juri.lelli@redhat.com>
To: rafael.j.wysocki@intel.com, peterz@infradead.org
Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org,
	Juri Lelli <juri.lelli@redhat.com>,
	Ingo Molnar <mingo@redhat.com>,
	Viresh Kumar <viresh.kumar@linaro.org>,
	Claudio Scordino <claudio@evidence.eu.com>,
	Luca Abeni <luca.abeni@santannapisa.it>
Subject: [PATCH] kernel/sched/cpufreq_schedutil: remove stale comment
Date: Wed,  9 May 2018 10:40:51 +0200	[thread overview]
Message-ID: <20180509084051.12107-1-juri.lelli@redhat.com> (raw)

After commit 794a56ebd9a57 ("sched/cpufreq: Change the worker kthread to
SCHED_DEADLINE") schedutil kthreads are "ignored" for a clock frequency
selection point of view, so the potential corner case for RT tasks is not
possible at all now.

Remove the stale comment mentioning it.

Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Claudio Scordino <claudio@evidence.eu.com>
Cc: Luca Abeni <luca.abeni@santannapisa.it>
---
 kernel/sched/cpufreq_schedutil.c | 13 -------------
 1 file changed, 13 deletions(-)

diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index d2c6083304b4..23ef19070137 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -396,19 +396,6 @@ static void sugov_irq_work(struct irq_work *irq_work)
 
 	sg_policy = container_of(irq_work, struct sugov_policy, irq_work);
 
-	/*
-	 * For RT tasks, the schedutil governor shoots the frequency to maximum.
-	 * Special care must be taken to ensure that this kthread doesn't result
-	 * in the same behavior.
-	 *
-	 * This is (mostly) guaranteed by the work_in_progress flag. The flag is
-	 * updated only at the end of the sugov_work() function and before that
-	 * the schedutil governor rejects all other frequency scaling requests.
-	 *
-	 * There is a very rare case though, where the RT thread yields right
-	 * after the work_in_progress flag is cleared. The effects of that are
-	 * neglected for now.
-	 */
 	kthread_queue_work(&sg_policy->worker, &sg_policy->work);
 }
 
-- 
2.14.3

             reply	other threads:[~2018-05-09  8:41 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-09  8:40 Juri Lelli [this message]
2018-05-09  8:41 ` Viresh Kumar
2018-05-13  8:40   ` Rafael J. Wysocki

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