From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 41A4CC1975A for ; Wed, 25 Mar 2020 16:56:44 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id A28B420772 for ; Wed, 25 Mar 2020 16:56:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A28B420772 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linutronix.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 48nZ5j1HpPzDqbX for ; Thu, 26 Mar 2020 03:56:41 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=linutronix.de (client-ip=2a0a:51c0:0:12e:550::1; helo=galois.linutronix.de; envelope-from=bigeasy@linutronix.de; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=linutronix.de Received: from Galois.linutronix.de (Galois.linutronix.de [IPv6:2a0a:51c0:0:12e:550::1]) (using TLSv1.2 with cipher DHE-RSA-AES256-SHA256 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 48nZ3d0DBbzDqML for ; Thu, 26 Mar 2020 03:54:53 +1100 (AEDT) Received: from bigeasy by Galois.linutronix.de with local (Exim 4.80) (envelope-from ) id 1jH9IM-00061w-Lf; Wed, 25 Mar 2020 17:54:22 +0100 Date: Wed, 25 Mar 2020 17:54:22 +0100 From: Sebastian Siewior To: "Paul E. McKenney" Subject: Re: Documentation/locking/locktypes: Further clarifications and wordsmithing Message-ID: <20200325165422.hfxzkxcj3jhqcstr@linutronix.de> References: <20200323025501.GE3199@paulmck-ThinkPad-P72> <87r1xhz6qp.fsf@nanos.tec.linutronix.de> <20200325002811.GO19865@paulmck-ThinkPad-P72> <87wo78y5yy.fsf@nanos.tec.linutronix.de> <20200325160212.oavrni7gmzudnczv@linutronix.de> <20200325163919.GU19865@paulmck-ThinkPad-P72> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <20200325163919.GU19865@paulmck-ThinkPad-P72> X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-usb@vger.kernel.org, linux-ia64@vger.kernel.org, Peter Zijlstra , linux-pci@vger.kernel.org, Oleg Nesterov , Guo Ren , Joel Fernandes , Vincent Chen , Thomas Gleixner , Davidlohr Bueso , linux-acpi@vger.kernel.org, Brian Cain , Jonathan Corbet , linux-hexagon@vger.kernel.org, "Rafael J. Wysocki" , linux-csky@vger.kernel.org, Ingo Molnar , Linus Torvalds , Darren Hart , Zhang Rui , Len Brown , Fenghua Yu , Arnd Bergmann , linux-pm@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Greentime Hu , Bjorn Helgaas , Kurt Schwemmer , platform-driver-x86@vger.kernel.org, Kalle Valo , kbuild test robot , Felipe Balbi , Michal Simek , Tony Luck , Nick Hu , Geoff Levand , Greg Kroah-Hartman , Randy Dunlap , linux-wireless@vger.kernel.org, LKML , Davidlohr Bueso , netdev@vger.kernel.org, Logan Gunthorpe , "David S. Miller" , Andy Shevchenko Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On 2020-03-25 09:39:19 [-0700], Paul E. McKenney wrote: > > > --- a/Documentation/locking/locktypes.rst > > > +++ b/Documentation/locking/locktypes.rst > > =E2=80=A6 > > > +rw_semaphore > > > +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > > > + > > > +rw_semaphore is a multiple readers and single writer lock mechanism. > > > + > > > +On non-PREEMPT_RT kernels the implementation is fair, thus preventing > > > +writer starvation. > > > + > > > +rw_semaphore complies by default with the strict owner semantics, bu= t there > > > +exist special-purpose interfaces that allow non-owner release for re= aders. > > > +These work independent of the kernel configuration. > >=20 > > This reads funny, could be my English. "This works independent =E2=80= =A6" maybe? >=20 > The "These" refers to "interfaces", which is plural, so "These" rather > than "This". But yes, it is a bit awkward, because you have to skip > back past "readers", "release", and "non-owner" to find the implied > subject of that last sentence. >=20 > So how about this instead, making the implied subject explicit? >=20 > rw_semaphore complies by default with the strict owner semantics, but the= re > exist special-purpose interfaces that allow non-owner release for readers. > These interfaces work independent of the kernel configuration. Yes, perfect. Thank you. > Thanx, Paul Sebastian