Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753368Ab1CPSFD (ORCPT ); Wed, 16 Mar 2011 14:05:03 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:37831 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751606Ab1CPSE6 convert rfc822-to-8bit (ORCPT ); Wed, 16 Mar 2011 14:04:58 -0400 Subject: Re: [RFC PATCH 0/4] perf: Custom contexts From: Peter Zijlstra To: Arnaldo Carvalho de Melo Cc: Masami Hiramatsu , Frederic Weisbecker , LKML , Paul Mackerras , Stephane Eranian , Steven Rostedt , Thomas Gleixner , Hitoshi Mitake , "2nddept-manager@sdl.hitachi.co.jp" <2nddept-manager@sdl.hitachi.co.jp> In-Reply-To: <20110316175310.GA2861@ghostprotocols.net> References: <20110314205100.GG6139@nowhere> <20110314210315.GC2388@ghostprotocols.net> <20110314212050.GH6139@nowhere> <20110314215603.GD2388@ghostprotocols.net> <20110314224344.GA11443@nowhere> <20110314230211.GG2388@ghostprotocols.net> <20110315185812.GB6605@nowhere> <20110315192422.GF7011@ghostprotocols.net> <20110316010304.GB7760@nowhere> <4D80DB75.6060408@hitachi.com> <20110316175310.GA2861@ghostprotocols.net> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Wed, 16 Mar 2011 19:02:37 +0100 Message-ID: <1300298557.2203.1810.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1917 Lines: 40 On Wed, 2011-03-16 at 14:53 -0300, Arnaldo Carvalho de Melo wrote: > Em Thu, Mar 17, 2011 at 12:47:01AM +0900, Masami Hiramatsu escreveu: > > (2011/03/16 10:03), Frederic Weisbecker wrote: > > > Doh you're right. && would have two meaning. > > > No we should probably keep a && b has a meaning of we are > > > in the range a AND in the range b. Both at the same time, with > > > a evaluated first and then b. We also need to ensure than > > > a && b doesn't mean the same than b && a. You're right, perhaps > > > we need another operator to expression inclusion, or we need to > > > assume that specific meaning of &&. > > > > > > For what I wanted to express in the example above, || seem be the > > > right choice: -e inst*@(..lock:*acquire(B) || lock:*release(B)..) > > > > > > So || would mean union and && would mean inclusion. > > > > Hmm, would we really need that kind of complex rules? > > It seems that we only need union case. If so, I'd suggest > > you to use ',' to express that, instead of ||. > > > > -e inst*@(..lock:*acquire(B),lock:*release(B)..) > > Yeah, I somehow was avoiding the comma operator because it could be used > to represent multiple events, but then its a different context, using it > to represent a circular list of ranges in the @ (at, location) expression > seems ok. > > 1. '..lock:*acquire(B)' is armed, 'lock:*release(B)..' isn't > 2. '..lock:*acquire(B)' trigers, which causes 'lock:*release(B)..' to be > armed > 3. 'lock:*release(B)..' triggers, which causes '..lock:*acquire(B)' to > be armed, rinse, repeat How about we start writing proper EBNF syntax rules for this stuff, its getting seriously out of hand. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/