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Date: Mon, 8 Jan 2018 19:42:11 -0800
From: Tejun Heo <tj@kernel.org>
To: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Prateek Sood <prsood@codeaurora.org>,
        Peter Zijlstra <peterz@infradead.org>, avagin@gmail.com,
        mingo@kernel.org, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH] cgroup/cpuset: fix circular locking dependency
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Hello, Paul.

On Mon, Jan 08, 2018 at 04:31:27PM -0800, Paul E. McKenney wrote:
> +static int __init rcu_init_wq_rescuer(void)
> +{
> +	WARN_ON(init_rescuer(rcu_gp_workqueue));
> +	return 0;
> +}
> +core_initcall(rcu_init_wq_rescuer);

So, what I don't get is why RCU needs to call this explicitly.
core_initcall() is after workqueue_init() anyway.  Why am I missing?

Thanks.

-- 
tejun

From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: Re: [PATCH] cgroup/cpuset: fix circular locking dependency
Date: Mon, 8 Jan 2018 19:42:11 -0800
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To: "Paul E. McKenney" <paulmck-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
Cc: Prateek Sood <prsood-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>, Peter Zijlstra <peterz-wEGCiKHe2LqWVfeAwA7xHQ@public.gmane.org>, avagin-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, mingo-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, sramana-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org

Hello, Paul.

On Mon, Jan 08, 2018 at 04:31:27PM -0800, Paul E. McKenney wrote:
> +static int __init rcu_init_wq_rescuer(void)
> +{
> +	WARN_ON(init_rescuer(rcu_gp_workqueue));
> +	return 0;
> +}
> +core_initcall(rcu_init_wq_rescuer);

So, what I don't get is why RCU needs to call this explicitly.
core_initcall() is after workqueue_init() anyway.  Why am I missing?

Thanks.

-- 
tejun