Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757954Ab3GZD5W (ORCPT ); Thu, 25 Jul 2013 23:57:22 -0400 Received: from smtpauth03h.mfg.siteprotect.com ([64.26.60.134]:52025 "EHLO smtpauth03.mfg.siteprotect.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753924Ab3GZD5V (ORCPT ); Thu, 25 Jul 2013 23:57:21 -0400 Date: Thu, 25 Jul 2013 23:58:09 -0400 (EDT) From: Vince Weaver X-X-Sender: vince@pianoman.cluster.toy To: Andi Kleen cc: Andi Kleen , acme@infradead.org, mingo@kernel.org, linux-kernel@vger.kernel.org, Peter Zijlstra , Stephane Eranian , torvalds@linux-foundation.org, trinity@vger.kernel.org Subject: Re: [PATCH 1/2] tools, perf: Add a precise event qualifier v2 In-Reply-To: <20130724190537.GW6123@two.firstfloor.org> Message-ID: References: <1374501138-13496-1-git-send-email-andi@firstfloor.org> <20130723060108.GA18396@tassilo.jf.intel.com> <20130723225150.GT6123@two.firstfloor.org> <20130724190537.GW6123@two.firstfloor.org> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-CTCH-Spam: Unknown X-CTCH-RefID: str=0001.0A020206.51F1F3A0.008B,ss=1,re=0.000,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1334 Lines: 34 On Wed, 24 Jul 2013, Andi Kleen wrote: > Sorry I meant flags as an alias of "the 64bits currently occupied by the > bitfield". Perhaps the name choice was not very good. > > "flags_bitfield" ? > > So the tool would only need to know that, not every bit. > > In theory it could be also generalized as a byte offset to perf_event, > but that may be overengineered. I somehow doubt this would be acceptable. If it were, we could have had a somewhat better interface by just having the event fields be a list of values without involving format/* at all, something like config=0x58034;config1=0x20;precise_ip=0x4 For whatever reason things have to be human readable, and I don't think just having an opaque 64-bit "flags" value will be accepted. I'm likely wrong though, I have a very low accuracy rate for predicting future perf_event design decisions. This is all complicated by the intertwined nature of the perf_event ABI and the perf tool, and the way that there's at least three or four different ways to specify the same event from the perf tool command line. Vince -- 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/