From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760101AbaCUCqh (ORCPT ); Thu, 20 Mar 2014 22:46:37 -0400 Received: from mga11.intel.com ([192.55.52.93]:61419 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751671AbaCUCqf convert rfc822-to-8bit (ORCPT ); Thu, 20 Mar 2014 22:46:35 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,700,1389772800"; d="scan'208";a="503313303" From: "Dilger, Andreas" To: Oleg Nesterov , Peter Zijlstra CC: Peng Tao , Linux Kernel Mailing List , Ingo Molnar , "Drokin, Oleg" Subject: Re: [PATCH 0/2] wait: introduce WQ_FLAG_EXCLUSIVE_HEAD Thread-Topic: [PATCH 0/2] wait: introduce WQ_FLAG_EXCLUSIVE_HEAD Thread-Index: AQHPRGVDSr7HR/JAHUWOja21VYaTsJrq52qA Date: Fri, 21 Mar 2014 02:45:47 +0000 Message-ID: References: <1395148208-2209-1-git-send-email-bergwolf@gmail.com> <20140318133331.GA23193@laptop.programming.kicks-ass.net> <20140318140504.GD23193@laptop.programming.kicks-ass.net> <20140318154724.GA5669@redhat.com> <20140319164907.GA10113@redhat.com> <20140319165747.GC8557@laptop.programming.kicks-ass.net> <20140319171906.GA11377@redhat.com> <20140320175111.GA7375@redhat.com> In-Reply-To: <20140320175111.GA7375@redhat.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.252.132.228] Content-Type: text/plain; charset="us-ascii" Content-ID: <88B44CC901116F47B8958A66FDA2FC96@intel.com> Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2014/03/20, 11:51 AM, "Oleg Nesterov" wrote: >On 03/19, Oleg Nesterov wrote: >> >> OK, I'll try to test/cleanup/resend tomorrow. > >Cough. Still un-tested, sorry. I will test it somehow and report, >but I'd like to send this for review right now. > >Because I simply can't decide what the new flag should actually >do, so please ack/nack the semantics/naming at least. > >Changes: > > 1. I decided it would be better to change __wait_event() > to accept wait.flags right now. This looks better in > any case to me, and otherwise we need to introduce the > __wait_exclusive_enum. > > The change looks trivial (both actually), please tell > me if you think it doesn't deserve a separate patch. > > 2. I won't insist, but WQ_FLAG_EXCLUSIVE_HEAD can be used > without WQ_FLAG_EXCLUSIVE. > > Unlikely this can be useful, but it looks more natural > this way. Otherwise we need to add another check to > ensure that WQ_FLAG_EXCLUSIVE_HEAD can't come alone. > > However, perhaps this means the new flag needs another > name. I agree in advance with any. What about: #define WQ_FLAG_HEAD 0x02 #define WQ_FLAG_EXCLUSIVE_HEAD (WQ_FLAG_HEAD | WQ_FLAG_EXCLUSIVE) That avoids having WQ_FLAG_EXCLUSIVE_HEAD not actually meaning "exclusive"? Patches look reasonable at first glance. The second patch would need to be changed to handle that WQ_FLAG_EXCLUSIVE_HEAD has both bits set (probably just replace uses of WQ_FLAG_EXCLUSIVE_HEAD with WQ_FLAG_HEAD). Cheers, Andreas -- Andreas Dilger Lustre Software Architect Intel High Performance Data Division