Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756007Ab0AVRm3 (ORCPT ); Fri, 22 Jan 2010 12:42:29 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755443Ab0AVRm1 (ORCPT ); Fri, 22 Jan 2010 12:42:27 -0500 Received: from casper.infradead.org ([85.118.1.10]:43738 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755215Ab0AVRm0 (ORCPT ); Fri, 22 Jan 2010 12:42:26 -0500 Subject: RE: [Ptools-perfapi] [perfmon2] [PATCH] perf_events: AMD event scheduling (v1) From: Peter Zijlstra To: John McCalpin Cc: "'Dan Terpstra'" , "eranian@google.com" , "linux-kernel@vger.kernel.org" , "ptools-perfapi@eecs.utk.edu" , "perfmon2-devel@lists.sf.net" , "fweisbec@gmail.com" , "paulus@samba.org" , "mingo@elte.hu" , "davem@davemloft.net" In-Reply-To: References: <4b5991c4.0c58560a.44d3.ffffeedc@mx.google.com> <05F95E05F0394ED3B66F16ACA8ED4650@terpstrat60p> Content-Type: text/plain; charset="UTF-8" Date: Fri, 22 Jan 2010 18:42:01 +0100 Message-ID: <1264182121.4283.1549.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1085 Lines: 25 On Fri, 2010-01-22 at 11:33 -0600, John McCalpin wrote: > * Think of the system as having four performance monitors per core > *plus* four performance monitors for the "shared" structures on the > chip (L3, crossbar, HyperTransport links, memory controllers). Would have been nice to have them as a separately addressable pmu instead of shadowing the logical cpu's pmu. But that's all ancient history of course.. > There is an additional hazard when working with early K8 processors -- > a hardware bug causes the counts of all shared counters to be reset to > zero any time any shared register is programmed. This makes > "protecting" users somewhat more difficult.... Could you qualify early k8 a bit more, it shouldn't be hard to add a quirk for a specific set of cpus to read/reset all counters before writing to the shared pmu. -- 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/