Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760233Ab3JPI2s (ORCPT ); Wed, 16 Oct 2013 04:28:48 -0400 Received: from mail-oa0-f52.google.com ([209.85.219.52]:41776 "EHLO mail-oa0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755174Ab3JPI2p (ORCPT ); Wed, 16 Oct 2013 04:28:45 -0400 MIME-Version: 1.0 In-Reply-To: <20131016061502.GB21109@gmail.com> References: <20131015161843.GA17653@quad> <20131016061502.GB21109@gmail.com> Date: Wed, 16 Oct 2013 10:28:45 +0200 Message-ID: Subject: Re: [PATCH] perf: revert PERF_RECORD_MMAP2 support From: Stephane Eranian To: Ingo Molnar Cc: LKML , "mingo@elte.hu" , Peter Zijlstra , David Ahern , Arnaldo Carvalho de Melo , "ak@linux.intel.com" , Jiri Olsa , Hugh Dickins Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3094 Lines: 71 On Wed, Oct 16, 2013 at 8:15 AM, Ingo Molnar wrote: > > * Stephane Eranian wrote: > >> >> This unified patch removes the following commits >> for both kernel and perf tool: >> >> 6adb0b0 perf tools: Add default handler for mmap2 events >> 384c671 perf trace: Add mmap2 handler >> 5c5e854 perf tools: Add attr->mmap2 support >> d008d52 perf: Fix up MMAP2 buffer space reservation >> 13d7a24 perf: Add attr->mmap2 attribute to an event >> >> The MMAP2 record extension is not quite ready for prime time. >> We have identified address space cases where mappings would >> not be reported properly when apps fiddled directly with clone() >> and VM_CLONE. We will revisit the patch series soon. >> >> Signed-off-by: Stephane Eranian >> --- >> include/uapi/linux/perf_event.h | 24 +---------------- >> kernel/events/core.c | 47 +++----------------------------- >> tools/perf/builtin-annotate.c | 1 - >> tools/perf/builtin-inject.c | 15 ----------- >> tools/perf/builtin-mem.c | 1 - >> tools/perf/builtin-report.c | 1 - >> tools/perf/builtin-script.c | 1 - >> tools/perf/builtin-trace.c | 1 - >> tools/perf/tests/perf-record.c | 15 +++-------- >> tools/perf/util/build-id.c | 1 - >> tools/perf/util/event.c | 56 +++++++++------------------------------ >> tools/perf/util/event.h | 19 ------------- >> tools/perf/util/evsel.c | 16 +++-------- >> tools/perf/util/header.c | 3 --- >> tools/perf/util/machine.c | 53 +----------------------------------- >> tools/perf/util/machine.h | 1 - >> tools/perf/util/map.c | 8 +----- >> tools/perf/util/map.h | 8 ++---- >> tools/perf/util/session.c | 27 +------------------ >> tools/perf/util/tool.h | 1 - >> 20 files changed, 30 insertions(+), 269 deletions(-) > > Ugh, that's way too large. > > I thought the plan was to do a minimal revert. Is there really no way to > do this in a (much) shorter fashion? > > For example by a simple patch that returns -EINVAL (or -ENOSYS) if the new > flag is used - i.e. behaves like the old kernel in that regard - but > leaves the rest in place. (the 'rest' will hopefully be fixed for v3.13) > That's what I did in my initial revert patch. But it did not include the perf tool revert. I believe in the end, we will still go with the extended MMAP record and not with the physical address (which adds a PERF_SAMPLE_*). So we can leave the attr->mmap2 bit defined and return -EINVAL for now. As for the perf tool, we can remove everything and add that later on because the layout of the MMAP2 record may change. > Tooling will then fall back as if it was an old kernel - i.e. no changes > needed there at all. Right? > Yes. -- 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/