From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751275AbcGOO7a (ORCPT ); Fri, 15 Jul 2016 10:59:30 -0400 Received: from mx1.redhat.com ([209.132.183.28]:39525 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750894AbcGOO72 (ORCPT ); Fri, 15 Jul 2016 10:59:28 -0400 Date: Fri, 15 Jul 2016 16:59:23 +0200 From: Jiri Olsa To: Wang Nan Cc: acme@kernel.org, lizefan@huawei.com, linux-kernel@vger.kernel.org, pi3orama@163.com, He Kuang , Arnaldo Carvalho de Melo , Jiri Olsa , Masami Hiramatsu , Namhyung Kim , Nilay Vaish Subject: Re: [PATCH v16 14/15] perf tools: Don't warn about out of order event if write_backward is used Message-ID: <20160715145923.GA29695@krava> References: <1468485287-33422-1-git-send-email-wangnan0@huawei.com> <1468485287-33422-15-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1468485287-33422-15-git-send-email-wangnan0@huawei.com> User-Agent: Mutt/1.6.2 (2016-07-01) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.25]); Fri, 15 Jul 2016 14:59:27 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 14, 2016 at 08:34:46AM +0000, Wang Nan wrote: > If write_backward attribute is set, records are written into kernel > ring buffer from end to beginning, but read from beginning to end. so IIUIC they are stored from the newest to the oldest one right? we might want to sort them back when reading the perf.data, or mark the area in the data section and trat it specially or just make ordered_events__queue to recognize backward data and buffer long enough before pushing the sample to higher level or any other way that would make sense ;-) however this might come as follow up update, no reason to hold this patchset on this jirka