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Date: Fri, 21 Dec 2012 18:15:23 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Tejun Heo <tj@kernel.org>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH 25/25] ipc: don't use [delayed_]work_pending()
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On Fri, 21 Dec 2012 17:57:15 -0800 Tejun Heo <tj@kernel.org> wrote:

> There's no need to test whether a (delayed) work item in pending
> before queueing, flushing or cancelling it.  Most uses are unnecessary
> and quite a few of them are buggy.

> -		if (!work_pending(&ipc_memory_wq))
> -			schedule_work(&ipc_memory_wq);
> +		schedule_work(&ipc_memory_wq);

Well, the new code is a ton slower than the old code if the work is
frequently pending, so some care is needed with such a conversion.

That's not an issue for the IPC callsite - memory offlining isn't
frequent.

> ...
>
> Please let me know how this patch should be routed.  I can take it
> through the workqueue tree if necessary.
> 

Please merge this one yourself.