From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Howells <dhowells@redhat.com>
Subject: Re: [RFC] sched: implement the exclusive wait queue as a LIFO queue
Date: Wed, 28 Apr 2010 16:00:06 +0100
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Cc: dhowells@redhat.com, Ingo Molnar <mingo@elte.hu>,
	Alexander Viro <viro@zeniv.linux.org.uk>,
	Andrew Morton <akpm@linux-foundation.org>,
	"Eric W. Biederman" <ebiederm@xmission.com>,
	Davide Libenzi <davidel@xmailserver.org>,
	Roland Dreier <rolandd@cisco.com>,
	Stefan Richter <stefanr@s5r6.in-berlin.de>,
	Peter Zijlstra <a.p.zijlstra@chello.nl>,
	"David S. Miller" <davem@davemloft.net>,
	Eric Dumazet <dada1@cosmosbay.com>,
	Christoph Lameter <cl@linux.com>,
	Andreas Herrmann <andreas.herrmann3@amd.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Takashi Iwai <tiwai@suse.de>, linux-fsdevel@vger.kernel.org,
	linux-kernel@vger.kernel.org
To: Changli Gao <xiaosuo@gmail.com>
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Changli Gao <xiaosuo@gmail.com> wrote:

> > How often do the two actually mix? =A0And if they do, is that reall=
y an
> > error?
>=20
> The sock.sk_sleep is used by exclusive and non-exclusive wait queues.
> exclusive and non-exclusive is identified by wait queues, not wait
> queue heads. Maybe there is a historical reason. It is much like a
> hack.

But is it actually used in both modes at the same time?

David