From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756250AbbJUQxG (ORCPT ); Wed, 21 Oct 2015 12:53:06 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:39974 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756074AbbJUQxA (ORCPT ); Wed, 21 Oct 2015 12:53:00 -0400 Date: Wed, 21 Oct 2015 18:52:52 +0200 From: Peter Zijlstra To: Andi Kleen Cc: Andi Kleen , linux-kernel@vger.kernel.org, Ingo Molnar , Thomas Gleixner Subject: Re: [PATCH] x86, perf: Use INST_RETIRED.PREC_DIST for cycles:pp on Skylake Message-ID: <20151021165252.GJ3604@twins.programming.kicks-ass.net> References: <1445295496-8550-1-git-send-email-andi@firstfloor.org> <20151020113608.GC17308@twins.programming.kicks-ass.net> <20151020222844.GK3533@two.firstfloor.org> <20151021080947.GA2881@worktop.programming.kicks-ass.net> <20151021152608.GG15102@tassilo.jf.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20151021152608.GG15102@tassilo.jf.intel.com> User-Agent: Mutt/1.5.21 (2012-12-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 21, 2015 at 08:26:08AM -0700, Andi Kleen wrote: > So it turns out that UOPS_RETIRED.ALL+pebs only works by accident > on Skylake. It's not in the specification. Accident or not, it works and you've tested it. Might as well keep it. Specs can be updated. Also, even with the SNB 'hickup' they still haven't got the memo that cycles is important for PEBS ?