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Date: Wed, 18 Dec 2013 16:41:28 -0500
From: Tejun Heo <tj@kernel.org>
To: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Nigel Cunningham <nigel@nigelcunningham.com.au>,
        "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
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        Oleg Nesterov <oleg@redhat.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Fengguang Wu <fengguang.wu@intel.com>
Subject: Re: [PATCH] libata, freezer: avoid block device removal while system
 is frozen
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On Wed, Dec 18, 2013 at 04:39:36PM -0500, Tejun Heo wrote:
> Yeah, we can just rip out the whole freezer support and let the
> caller's pm notification hooks implement it by doing
> 
> 	workqueue_set_max_active(wq, 0);
> 	flush_workqueue(wq);

Oops, the above doesn't work but I can trivially add a new interface
for this.  Something which waits for the max_active to drop below the
newly set level before returning.

	workqueue_set_max_active_and_wait(wq, 0);

Thanks.

-- 
tejun