From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753777AbdKMOt2 convert rfc822-to-8bit (ORCPT ); Mon, 13 Nov 2017 09:49:28 -0500 Received: from mga07.intel.com ([134.134.136.100]:63778 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753751AbdKMOt0 (ORCPT ); Mon, 13 Nov 2017 09:49:26 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.44,389,1505804400"; d="scan'208";a="1003275" From: "Liang, Kan" To: Wang Nan , "linux-kernel@vger.kernel.org" , "acme@kernel.org" , "jolsa@redhat.com" , "namhyung@kernel.org" Subject: RE: [PATCH 0/7] perf tools: Clarify overwrite and backward, bugfix Thread-Topic: [PATCH 0/7] perf tools: Clarify overwrite and backward, bugfix Thread-Index: AQHTXCBAmnnowzL4hU6zXar67EvG7KMSU7OQ Date: Mon, 13 Nov 2017 14:49:20 +0000 Message-ID: <37D7C6CF3E00A74B8858931C1DB2F077537E0F67@SHSMSX103.ccr.corp.intel.com> References: <20171113013809.212417-1-wangnan0@huawei.com> In-Reply-To: <20171113013809.212417-1-wangnan0@huawei.com> Accept-Language: zh-CN, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-titus-metadata-40: eyJDYXRlZ29yeUxhYmVscyI6IiIsIk1ldGFkYXRhIjp7Im5zIjoiaHR0cDpcL1wvd3d3LnRpdHVzLmNvbVwvbnNcL0ludGVsMyIsImlkIjoiNzkzY2NhYzAtZWRmMy00YWJmLTljNzAtYWQ5YmJjOGY4MmViIiwicHJvcHMiOlt7Im4iOiJDVFBDbGFzc2lmaWNhdGlvbiIsInZhbHMiOlt7InZhbHVlIjoiQ1RQX0lDIn1dfV19LCJTdWJqZWN0TGFiZWxzIjpbXSwiVE1DVmVyc2lvbiI6IjE2LjUuOS4zIiwiVHJ1c3RlZExhYmVsSGFzaCI6Ik9PMEZYdGZzN01MRkd0M3BIcTBnYWJyZTY0MXZHb2paU0FUUjdaRmJQSlE9In0= x-ctpclassification: CTP_IC dlp-product: dlpe-windows dlp-version: 11.0.0.116 dlp-reaction: no-action x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > Based on previous discussion, perf needs to support only two types > of ringbuffer: read-write + forward, readonly + backward. This patchset > completly removes the concept of 'overwrite' from code level, controls > mapping permission using write_backward instead. I think I suggested to remove the concept of backward/forward, keep the overwrite. That's from user's perspective. Here you use read-write + forward and readonly + backward, which should be from kernel 's perspective. It's OK for me either. However, we should make the concepts connected by clearly documented, not just in changelog. I suggest you may create a new file, ringbuffer.txt, in Documentation to explain, the types of ringbuffer, how do they work, what's connections between overwrite and readonly + backward, and so on. > > Wang Nan (7): > perf mmap: Fix perf backward recording > perf tests: Set evlist of test__backward_ring_buffer() to !overwrite > perf tests: Set evlist of test__sw_clock_freq() to !overwrite > perf tests: Set evlist of test__basic_mmap() to !overwrite > perf tests: Set evlist of test__task_exit() to !overwrite > perf tools: Remove 'overwrite' concept from code level > perf tools: Remove prot field in mmap param > You had another related fix "perf tool: Don't discard prev in backward mode" https://lkml.org/lkml/2017/10/12/408 It has not been merged yet. It needs to backport. I think you may want to add it in this series as well. Thanks, Kan > tools/perf/arch/x86/tests/perf-time-to-tsc.c | 2 +- > tools/perf/builtin-kvm.c | 2 +- > tools/perf/builtin-record.c | 4 ++-- > tools/perf/builtin-top.c | 2 +- > tools/perf/builtin-trace.c | 2 +- > tools/perf/tests/backward-ring-buffer.c | 2 +- > tools/perf/tests/bpf.c | 2 +- > tools/perf/tests/code-reading.c | 2 +- > tools/perf/tests/keep-tracking.c | 2 +- > tools/perf/tests/mmap-basic.c | 2 +- > tools/perf/tests/openat-syscall-tp-fields.c | 2 +- > tools/perf/tests/perf-record.c | 2 +- > tools/perf/tests/sw-clock.c | 2 +- > tools/perf/tests/switch-tracking.c | 2 +- > tools/perf/tests/task-exit.c | 2 +- > tools/perf/util/evlist.c | 21 ++++++++++----------- > tools/perf/util/evlist.h | 6 ++---- > tools/perf/util/mmap.c | 10 +++++----- > tools/perf/util/mmap.h | 6 +++--- > tools/perf/util/python.c | 10 +++++----- > 20 files changed, 41 insertions(+), 44 deletions(-) > > -- > 2.10.1