From mboxrd@z Thu Jan 1 00:00:00 1970 From: Changli Gao Subject: Re: [RFC] sched: implement the exclusive wait queue as a LIFO queue Date: Wed, 28 Apr 2010 22:53:16 +0800 Message-ID: References: <1272430986-20436-1-git-send-email-xiaosuo@gmail.com> <8526.1272447122@redhat.com> <6096.1272463619@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Ingo Molnar , Alexander Viro , Andrew Morton , "Eric W. Biederman" , Davide Libenzi , Roland Dreier , Stefan Richter , Peter Zijlstra , "David S. Miller" , Eric Dumazet , Christoph Lameter , Andreas Herrmann , Thomas Gleixner , Takashi Iwai , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org To: David Howells Return-path: Received: from mail-pw0-f46.google.com ([209.85.160.46]:62333 "EHLO mail-pw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751581Ab0D1Oxq convert rfc822-to-8bit (ORCPT ); Wed, 28 Apr 2010 10:53:46 -0400 In-Reply-To: <6096.1272463619@redhat.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Wed, Apr 28, 2010 at 10:06 PM, David Howells w= rote: > > I suspect you really want to have the semantics defined per-queue. =C2= =A0_Either_ a > queue is FIFO (such as processes waiting for a resource so they can d= o > something with it) _or_ it is LIFO (such as a pool of processes waiti= ng to be > given work). > > How often do the two actually mix? =C2=A0And if they do, is that real= ly an error? > 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. --=20 Regards=EF=BC=8C Changli Gao(xiaosuo@gmail.com) -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel= " in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html