From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754371Ab3AZVAJ (ORCPT ); Sat, 26 Jan 2013 16:00:09 -0500 Received: from one.firstfloor.org ([213.235.205.2]:53134 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754188Ab3AZVAH (ORCPT ); Sat, 26 Jan 2013 16:00:07 -0500 Date: Sat, 26 Jan 2013 22:00:00 +0100 From: Andi Kleen To: Ingo Molnar Cc: Andi Kleen , linux-kernel@vger.kernel.org, a.p.zijlstra@chello.nl, akpm@linux-foundation.org, acme@redhat.com, eranian@google.com, jolsa@redhat.com, namhyung@kernel.org, Andi Kleen Subject: Re: [PATCH 04/12] perf, x86: Support the TSX intx/intx_cp qualifiers v2 Message-ID: <20130126210000.GK30577@one.firstfloor.org> References: <1359151245-13179-1-git-send-email-andi@firstfloor.org> <1359151245-13179-5-git-send-email-andi@firstfloor.org> <20130126115402.GA13445@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130126115402.GA13445@gmail.com> User-Agent: Mutt/1.4.2.2i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jan 26, 2013 at 12:54:02PM +0100, Ingo Molnar wrote: > > * Andi Kleen wrote: > > > From: Andi Kleen > > > > Implement the TSX transaction and checkpointed transaction > > qualifiers for Haswell. This allows e.g. to profile the number > > of cycles in transactions. > > The changelog should explain why this is a basic feature that is > a must-have to have basic perf support. (i.e. default 'perf > record', 'perf report', 'perf stat' and 'perf top' works and is > meaningful.) The patch is not needed for primitive cycle sampling only. These qualifiers are a fundamental feature for any TSX tuning. If you don't care about TSX it's not fundamental. TSX tuning relies heavily on the PMU, so for any TSX work it's important. The 0/0 description has more references on the topic. It's not easy to use however with just this patch, the "perf stat -T" patch in the advanced series makes it easy to use. I will assume the description is sufficient and will not repost with a new changelog, as "basicness" of the patch is not a useful property to document in the long term git history. -Andi -- ak@linux.intel.com -- Speaking for myself only.