From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8FB03183CC4; Mon, 12 Aug 2024 13:53:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723470817; cv=none; b=n6u1BN4NxvCHh555QHXHwWW/zKN2M00MrS8v+Qfuif4Z4DR0EjNNulXWUuCBqZnL/LCa92R4pM+lqjDLuDpUeA83WPtjVPHpx0qT++tJAbz9pb1Ol+11tevSGtV8DqTUido1Drs1hvfb8Wwru9ETvtPION6iZfzJnVwQLBicuJw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723470817; c=relaxed/simple; bh=ijKQeoW1MoOBpXzF9QLNNelhDZlm4eAZ4KAnbLksRcU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=DJhBQxNU3gmJPYT81dXawp51mVGDrdYNdLlizujgL/Rzwamycfv3qxZbHfEg/B8Tjn4T/b6wsSHdIKQdLdsxinJ9Kuf4j8dmI8FyZRvi9kTFkKVJRWxs0YS8O9xtePpCxAPJeA4RPl8Is3gLEFkVv5RB71qigJ4VsWqcRq9AmF8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=YNVIw6qa; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="YNVIw6qa" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 857C0C4AF09; Mon, 12 Aug 2024 13:53:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1723470817; bh=ijKQeoW1MoOBpXzF9QLNNelhDZlm4eAZ4KAnbLksRcU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=YNVIw6qaWsPrwPdwsnlRLRy1Z7Fjir1TR4KRG4ENDZUWNp/yUOuCTIW9Gk+Z9BEEB gkl7U6mBvfFSoKys049kUToIRtf+0Z0oitaVWGAGsnchUh5Ny0CBD1PM/Ki185m24o uitF3wagx67wxMvpph3C327UYjWmyWOfze69QhK6F8tYGVa03hPbJHvyy2Vus1Arpq TtmBRQ5gOfceQHkufwylMvEjATJ7kZhHCCmM+aiynuIVzLox6CxxVJf1FCQLW4iDhW gUK2BVhkBDYc1K4zWIFFFfh+Y5j8BNeuu7YIOdWbGp+D11sLoKgrjNQq0CC0tw+KBl jXDbNnJh2cORA== Date: Mon, 12 Aug 2024 10:53:33 -0300 From: Arnaldo Carvalho de Melo To: Ian Rogers Cc: Adrian Hunter , Peter Zijlstra , Ingo Molnar , Namhyung Kim , Mark Rutland , Alexander Shishkin , Jiri Olsa , Kan Liang , John Garry , Will Deacon , James Clark , Mike Leach , Leo Yan , Suzuki K Poulose , Yicong Yang , Jonathan Cameron , Nick Terrell , Nick Desaulniers , Oliver Upton , Anshuman Khandual , Song Liu , Ilkka Koskinen , Athira Rajeev , Huacai Chen , Yanteng Si , Sun Haiyong , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v6 00/27] Constify tool pointers Message-ID: References: <20240718010023.1495687-1-irogers@google.com> <738b5c89-acb2-46a5-92a1-c36bd90abc30@intel.com> Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Fri, Jul 19, 2024 at 09:26:57AM -0700, Ian Rogers wrote: > On Fri, Jul 19, 2024 at 1:51 AM Adrian Hunter wrote: > > > > On 18/07/24 03:59, Ian Rogers wrote: > > > struct perf_tool provides a set of function pointers that are called > > > through when processing perf data. To make filling the pointers less > > > cumbersome, if they are NULL perf_tools__fill_defaults will add > > > default do nothing implementations. > > > > > > This change refactors struct perf_tool to have an init function that > > > provides the default implementation. The special use of NULL and > > > perf_tools__fill_defaults are removed. As a consequence the tool > > > pointers can then all be made const, which better reflects the > > > behavior a particular perf command would expect of the tool and to > > > some extent can reduce the cognitive load on someone working on a > > > command. > > > > > > v6: Rebase adding Adrian's reviewed-by/tested-by and Leo's tested-by. > > > > The tags were really meant only for patch 1, the email that was replied to. > > > > But now for patches 2 and 3: > > > > Reviewed-by: Adrian Hunter Applied 1-3, 4 is not applying, I'll look at it later. - Arnaldo > > Sorry for that, you'd mentioned that pt and bts testing which is > impacted by more than just patch 1. > > > Looking at patches 4 to 25, they do not seem to offer any benefit. > > > > Instead of patch 26, presumably perf_tool__fill_defaults() could > > be moved to __perf_session__new(), which perhaps would allow > > patch 27 as it is. > > What I'm trying to do in the series is make it so that the tool isn't > mutated during its use by session. Ideally we'd be passing a const > tool to session_new, that's not possible because there's a hack to fix > ordered events and pipe mode in session__new: > https://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools-next.git/tree/tools/perf/util/session.c?h=perf-tools-next#n275 > Imo, it isn't great to pass a tool to session__new where you say you > want ordered events and then session just goes to change that for you. > Altering that behavior was beyond the scope of this clean up, so tool > is only const after session__new. > > The reason for doing this is to make it so that when I have a tool I > can reason that nobody is doing things to change it under my feet. My > builtin_cmd is in charge of what the tool is rather than some code > buried in util that thought it was going to do me a favor. The code is > a refactor and so the benefit is intended to be for the developer and > how they reason about the use of tool. We generally use _init > functions rather than having _fill_defaults, so there is a consistency > argument. I don't expect any impact in terms of performance... Moving > perf_tool__fill_defaults to __perf_session__new had issues with the > existing code where NULL would be written over a function pointer > expecting the later fill_defaults to fix it up, doesn't address coding > consistency where _init is the norm, and adds another reason the tool > passed to session__new can't be const. > > Thanks, > Ian > > > > v5: Rebase dropping asan fix merged by Namhyung. > > > v4: Simplify perf_session__deliver_synth_attr_event following Adrian's > > > suggestions. > > > v3: Just remove auxtrace dummy tools [Adrian] and make s390-cpumsf > > > struct removal its own patch [Adrian]. > > > v2: Remove dummy tool initialization [Adrian] and make zero sized. Add > > > cs-etm fix for address sanitizer build, found necessary when > > > testing dummy tool change. > > > > > > Ian Rogers (27): > > > perf auxtrace: Remove dummy tools > > > perf s390-cpumsf: Remove unused struct > > > perf tool: Constify tool pointers > > > perf tool: Move fill defaults into tool.c > > > perf tool: Add perf_tool__init > > > perf kmem: Use perf_tool__init > > > perf buildid-list: Use perf_tool__init > > > perf kvm: Use perf_tool__init > > > perf lock: Use perf_tool__init > > > perf evlist: Use perf_tool__init > > > perf record: Use perf_tool__init > > > perf c2c: Use perf_tool__init > > > perf script: Use perf_tool__init > > > perf inject: Use perf_tool__init > > > perf report: Use perf_tool__init > > > perf stat: Use perf_tool__init > > > perf annotate: Use perf_tool__init > > > perf sched: Use perf_tool__init > > > perf mem: Use perf_tool__init > > > perf timechart: Use perf_tool__init > > > perf diff: Use perf_tool__init > > > perf data convert json: Use perf_tool__init > > > perf data convert ctf: Use perf_tool__init > > > perf test event_update: Ensure tools is initialized > > > perf kwork: Use perf_tool__init > > > perf tool: Remove perf_tool__fill_defaults > > > perf session: Constify tool > > > > > > tools/perf/arch/x86/util/event.c | 4 +- > > > tools/perf/bench/synthesize.c | 2 +- > > > tools/perf/builtin-annotate.c | 44 ++-- > > > tools/perf/builtin-buildid-list.c | 10 + > > > tools/perf/builtin-c2c.c | 33 ++- > > > tools/perf/builtin-diff.c | 30 ++- > > > tools/perf/builtin-evlist.c | 10 +- > > > tools/perf/builtin-inject.c | 159 ++++++------ > > > tools/perf/builtin-kmem.c | 20 +- > > > tools/perf/builtin-kvm.c | 19 +- > > > tools/perf/builtin-kwork.c | 33 ++- > > > tools/perf/builtin-lock.c | 41 ++-- > > > tools/perf/builtin-mem.c | 37 +-- > > > tools/perf/builtin-record.c | 47 ++-- > > > tools/perf/builtin-report.c | 67 +++-- > > > tools/perf/builtin-sched.c | 50 ++-- > > > tools/perf/builtin-script.c | 106 ++++---- > > > tools/perf/builtin-stat.c | 26 +- > > > tools/perf/builtin-timechart.c | 25 +- > > > tools/perf/builtin-top.c | 2 +- > > > tools/perf/builtin-trace.c | 4 +- > > > tools/perf/tests/cpumap.c | 6 +- > > > tools/perf/tests/dlfilter-test.c | 2 +- > > > tools/perf/tests/dwarf-unwind.c | 2 +- > > > tools/perf/tests/event_update.c | 9 +- > > > tools/perf/tests/stat.c | 6 +- > > > tools/perf/tests/thread-map.c | 2 +- > > > tools/perf/util/Build | 1 + > > > tools/perf/util/arm-spe.c | 55 +---- > > > tools/perf/util/auxtrace.c | 12 +- > > > tools/perf/util/auxtrace.h | 20 +- > > > tools/perf/util/bpf-event.c | 4 +- > > > tools/perf/util/build-id.c | 34 +-- > > > tools/perf/util/build-id.h | 8 +- > > > tools/perf/util/cs-etm.c | 39 +-- > > > tools/perf/util/data-convert-bt.c | 34 ++- > > > tools/perf/util/data-convert-json.c | 47 ++-- > > > tools/perf/util/event.c | 54 ++-- > > > tools/perf/util/event.h | 38 +-- > > > tools/perf/util/header.c | 6 +- > > > tools/perf/util/header.h | 4 +- > > > tools/perf/util/hisi-ptt.c | 6 +- > > > tools/perf/util/intel-bts.c | 37 +-- > > > tools/perf/util/intel-pt.c | 30 +-- > > > tools/perf/util/jitdump.c | 4 +- > > > tools/perf/util/s390-cpumsf.c | 11 +- > > > tools/perf/util/session.c | 366 +++------------------------- > > > tools/perf/util/session.h | 9 +- > > > tools/perf/util/synthetic-events.c | 80 +++--- > > > tools/perf/util/synthetic-events.h | 70 +++--- > > > tools/perf/util/tool.c | 294 ++++++++++++++++++++++ > > > tools/perf/util/tool.h | 18 +- > > > tools/perf/util/tsc.c | 2 +- > > > 53 files changed, 977 insertions(+), 1102 deletions(-) > > > create mode 100644 tools/perf/util/tool.c > > > > >