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Date: Tue, 15 Aug 2017 15:47:28 -0700
From: Davidlohr Bueso <dave@stgolabs.net>
Subject: Re: [PATCH 1/2] sched/wait: Break up long wake list walk
Message-ID: <20170815224728.GA1373@linux-80c1.suse>
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To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andi Kleen <ak@linux.intel.com>, Tim Chen <tim.c.chen@linux.intel.com>, Peter Zijlstra <peterz@infradead.org>, Ingo Molnar <mingo@elte.hu>, Kan Liang <kan.liang@intel.com>, Andrew Morton <akpm@linux-foundation.org>, Johannes Weiner <hannes@cmpxchg.org>, Jan Kara <jack@suse.cz>, linux-mm <linux-mm@kvack.org>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>

On Mon, 14 Aug 2017, Linus Torvalds wrote:

>On Mon, Aug 14, 2017 at 8:15 PM, Andi Kleen <ak@linux.intel.com> wrote:
>> But what should we do when some other (non page) wait queue runs into the
>> same problem?
>
>Hopefully the same: root-cause it.

Or you can always use wake_qs; which exists _exactly_ for the issues you
are running into. Note that Linus does not want them in general wait:

https://lkml.org/lkml/2017/7/7/605

... but you can always use them on your own if you really need to (ie locks,
ipc, etc).

Thanks,
Davidlohr

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