From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Paul E. McKenney" Subject: Re: [PATCH v2 0/9] Remove spin_unlock_wait() Date: Fri, 7 Jul 2017 07:41:07 -0700 Message-ID: <20170707144107.GA27202@linux.vnet.ibm.com> References: <20170629235918.GA6445@linux.vnet.ibm.com> <20170705232955.GA15992@linux.vnet.ibm.com> <063D6719AE5E284EB5DD2968C1650D6DD0033F01@AcuExch.aculab.com> <20170706160555.xc63yydk77gmttae@hirez.programming.kicks-ass.net> <20170706162024.GD2393@linux.vnet.ibm.com> <20170706165036.v4u5rbz56si4emw5@hirez.programming.kicks-ass.net> <20170707083128.wqk6msuuhtyykhpu@gmail.com> Reply-To: paulmck@linux.vnet.ibm.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Peter Zijlstra , David Laight , "linux-kernel@vger.kernel.org" , "netfilter-devel@vger.kernel.org" , "netdev@vger.kernel.org" , "oleg@redhat.com" , "akpm@linux-foundation.org" , "mingo@redhat.com" , "dave@stgolabs.net" , "manfred@colorfullife.com" , "tj@kernel.org" , "arnd@arndb.de" , "linux-arch@vger.kernel.org" , "will.deacon@arm.com" , "stern@rowland.harvard.edu" , "parri.andrea@gmail.com" , "torval To: Ingo Molnar Return-path: Content-Disposition: inline In-Reply-To: <20170707083128.wqk6msuuhtyykhpu@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netfilter-devel.vger.kernel.org On Fri, Jul 07, 2017 at 10:31:28AM +0200, Ingo Molnar wrote: [ . . . ] > In fact I'd argue that any future high performance spin_unlock_wait() user is > probably better off open coding the unlock-wait poll loop (and possibly thinking > hard about eliminating it altogether). If such patterns pop up in the kernel we > can think about consolidating them into a single read-only primitive again. I would like any reintroduction to include a header comment saying exactly what the consolidated primitive actually does and does not do. ;-) > I.e. I think the proposed changes are doing no harm, and the unavailability of a > generic primitive does not hinder future optimizations either in any significant > fashion. I will have a v3 with updated comments from Manfred. Thoughts on when/where to push this? The reason I ask is if this does not go in during this merge window, I need to fix the header comment on spin_unlock_wait(). Thanx, Paul