Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933526Ab1D1WQm (ORCPT ); Thu, 28 Apr 2011 18:16:42 -0400 Received: from aspirin.dii.utk.edu ([160.36.0.81]:46084 "EHLO aspirin.dii.utk.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932154Ab1D1WQl (ORCPT ); Thu, 28 Apr 2011 18:16:41 -0400 Date: Thu, 28 Apr 2011 18:16:22 -0400 (EDT) From: Vince Weaver To: Ingo Molnar cc: Arnaldo Carvalho de Melo , linux-kernel@vger.kernel.org, Andi Kleen , Peter Zijlstra , Stephane Eranian , Lin Ming , Arnaldo Carvalho de Melo , Thomas Gleixner , Peter Zijlstra Subject: Re: [PATCH 1/1] perf tools: Add missing user space support for config1/config2 In-Reply-To: <20110427065241.GF17079@elte.hu> Message-ID: References: <1303407662-15564-1-git-send-email-acme@infradead.org> <1303407662-15564-2-git-send-email-acme@infradead.org> <20110422063429.GA16643@elte.hu> <20110422080604.GA22611@elte.hu> <20110425175444.GC28239@elte.hu> <20110426073847.GB30630@elte.hu> <20110427065241.GF17079@elte.hu> User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1522 Lines: 33 On Wed, 27 Apr 2011, Ingo Molnar wrote: > Secondly, you are still quite wrong even with your revised opinion. Being able > to type '-e cycles' and '-e instructions' in perf and get ... cycles and > instructions counts/events, and the kernel helping that kind of approach is not > 'abstraction to the extreme', it's called 'common sense'. by your logic I should be able to delete a file by saying echo "delete /tmp/tempfile" > /dev/sdc1 because using unlink() is too low of an abstraction and confusing to the user. > The fact that perfmon and oprofile works via magic vendor-specific event string > incantations is one of the many design failures of those projects - not a > virtue. Well we disagree. I think one of perf_events biggest failings (among many) is that these generalized event definitions are shoved into the kernel. At least it bloats the kernel in an option commonly turned on by vendors. At worst it gives users a full sense of security in thinking these counters are A). Portable across architectures and B). Actually measure what they say they do. I know it is fun to reinvent the wheel, but you ignored decades of experience in dealing with perf-counters when you ran off and invented perf_events. It will bite you eventually. 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/