lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Message-Id: <20180509084051.12107-1-juri.lelli@redhat.com>
Date:   Wed,  9 May 2018 10:40:51 +0200
From:   Juri Lelli <juri.lelli@...hat.com>
To:     rafael.j.wysocki@...el.com, peterz@...radead.org
Cc:     linux-kernel@...r.kernel.org, linux-pm@...r.kernel.org,
        Juri Lelli <juri.lelli@...hat.com>,
        Ingo Molnar <mingo@...hat.com>,
        Viresh Kumar <viresh.kumar@...aro.org>,
        Claudio Scordino <claudio@...dence.eu.com>,
        Luca Abeni <luca.abeni@...tannapisa.it>
Subject: [PATCH] kernel/sched/cpufreq_schedutil: remove stale comment

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@...hat.com>
Cc: Ingo Molnar <mingo@...hat.com>
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: "Rafael J. Wysocki" <rafael.j.wysocki@...el.com>
Cc: Viresh Kumar <viresh.kumar@...aro.org>
Cc: Claudio Scordino <claudio@...dence.eu.com>
Cc: Luca Abeni <luca.abeni@...tannapisa.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

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ