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Date:   Thu, 16 Jan 2020 09:55:07 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Alexander Popov <alex.popov@linux.com>
Cc:     Linus Torvalds <torvalds@linux-foundation.org>,
        John Stultz <john.stultz@linaro.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Stephen Boyd <sboyd@kernel.org>,
        Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Juri Lelli <juri.lelli@redhat.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
        linux-kernel@vger.kernel.org, notify@kernel.org
Subject: Re: [PATCH 1/1] timer: Warn about schedule_timeout() called for
 tasks in TASK_RUNNING state
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In-Reply-To: <20200116095220.7368a604@gandalf.local.home>
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        <20200116095220.7368a604@gandalf.local.home>
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On Thu, 16 Jan 2020 09:52:20 -0500
Steven Rostedt <rostedt@goodmis.org> wrote:

> > --- a/kernel/time/timer.c
> > +++ b/kernel/time/timer.c
> > @@ -1887,6 +1887,11 @@ signed long __sched schedule_timeout(signed long timeout)
> >  		}
> >  	}
> >  
> > +#ifdef CONFIG_SCHED_DEBUG
> > +	WARN_ONCE(current->state == TASK_RUNNING,
> > +			"schedule_timeout for TASK_RUNNING\n");
> > +#endif
> > +  
> 
> But this can trigger false warnings. For example, if we are waiting on
> an event with a timeout:


Also, there are helpers here that you can use:

schedule_timeout_interruptible(signed long timeout);
schedule_timeout_uninterruptible(signed long timeout)

-- Steve