From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756928AbbFQQFP (ORCPT ); Wed, 17 Jun 2015 12:05:15 -0400 Received: from mail-ie0-f178.google.com ([209.85.223.178]:32929 "EHLO mail-ie0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755156AbbFQQFM (ORCPT ); Wed, 17 Jun 2015 12:05:12 -0400 Message-ID: <55819AB3.9060308@gmail.com> Date: Wed, 17 Jun 2015 10:05:07 -0600 From: David Ahern User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: kan.liang@intel.com, acme@kernel.org CC: linux-kernel@vger.kernel.org, ying.huang@intel.com, andi@firstfloor.org Subject: Re: [PATCH V3 1/2] perf,tools: add time out to force stop proc map processing References: <1434527812-17051-1-git-send-email-kan.liang@intel.com> In-Reply-To: <1434527812-17051-1-git-send-email-kan.liang@intel.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/17/15 1:56 AM, kan.liang@intel.com wrote: > diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c > index 793b150..ac6cf2a 100644 > --- a/tools/perf/util/event.c > +++ b/tools/perf/util/event.c > @@ -213,6 +213,8 @@ static int perf_event__synthesize_fork(struct perf_tool *tool, > return 0; > } > > +#define MMAP_TIMEOUT (50 * 1000000ULL) > + How did you determine 50msec is a good time? This seems really low to me considering the range of platforms supported by perf and various run time conditions. The default needs to work right on all platforms. Why not have the default be infinity and users who need the feature use the option provided in patch 2? David