Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755367Ab3J1C3p (ORCPT ); Sun, 27 Oct 2013 22:29:45 -0400 Received: from mail-qe0-f49.google.com ([209.85.128.49]:38866 "EHLO mail-qe0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754546Ab3J1C3o (ORCPT ); Sun, 27 Oct 2013 22:29:44 -0400 Date: Sun, 27 Oct 2013 22:37:46 -0400 (EDT) From: Vince Weaver To: linux-kernel@vger.kernel.org cc: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Will Deacon Subject: perf: PERF_EVENT_IOC_PERIOD on ARM vs everywhere else Message-ID: User-Agent: Alpine 2.10 (DEB 1266 2009-07-14) 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: 824 Lines: 21 Hello it was pointed out to me that in the 3.7 kernel (more specifically, 3581fe0ef37ce12ac7a4f74831168352ae848edc ) a change was made in the ARM architecture to change how PERF_EVENT_IOC_PERIOD is handled. Unlike other architectures, post-3.7 ARM updates the period right away rather than waiting until the next overflow. I can't find any discussion as to why this change was made. Should other architectures be updated to? I just wanted to find out the rationale for this before I update the manpage to reflect the difference in behaviors between architectures. 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/