Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933751Ab1D2Tc6 (ORCPT ); Fri, 29 Apr 2011 15:32:58 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:33173 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932543Ab1D2Tc5 (ORCPT ); Fri, 29 Apr 2011 15:32:57 -0400 Date: Fri, 29 Apr 2011 21:32:37 +0200 From: Ingo Molnar To: Vince Weaver 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 Message-ID: <20110429193237.GB15068@elte.hu> References: <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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-08-17) X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.3.1 -2.0 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1836 Lines: 44 * Vince Weaver wrote: > 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. Erm, unlink() does not pass magic hexa constants to the disk controller. unlink() is a high level interface that works across a vast range of disk controllers, disks, network mounted filesystems, in-RAM filesystems, in-ROM filesystems, clustered filesystems and other mediums. Just like that we can tell perf to count 'cycles', 'branches' or 'branch-misses' - all of these are relatively high level concepts (in the scope of CPUs) that work across a vast range of CPU types and models. Similarly, for offcore we want to introduce the concept of 'node local' versus 'remote' memory - perhaps with some events for inter-CPU traffic as well - because that probably covers most of the NUMA related memory profiling needs. Raw events are to perf what ioctls are to the VFS: small details nobody felt worth generalizing. My point in this discussion is that we do not offer new filesystems that support *only* ioctl calls ... Is this simple concept so hard to understand? Thanks, Ingo -- 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/