From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 61FBEC433DF for ; Fri, 5 Jun 2020 15:23:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 43E6D2077D for ; Fri, 5 Jun 2020 15:23:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728072AbgFEPXW (ORCPT ); Fri, 5 Jun 2020 11:23:22 -0400 Received: from mga03.intel.com ([134.134.136.65]:62408 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726551AbgFEPXW (ORCPT ); Fri, 5 Jun 2020 11:23:22 -0400 IronPort-SDR: 0i5P4oPuPZB2tYCgAstv9XkjFZaB0TI2oGynqEsQ9a0YqZguGHuDwckQxAXhDtKTl27NhR8Rvh eUcQ7YPnuwTg== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Jun 2020 08:23:21 -0700 IronPort-SDR: rbkcUFCN/LKfSajGEV9tyrwnhOSeFz4gn5T56Qb4I/tQebDM3sQGk5fnh1A0ydxr+Pt664nmhb g6ZQP5ik293Q== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,476,1583222400"; d="scan'208";a="305260844" Received: from linux.intel.com ([10.54.29.200]) by orsmga008.jf.intel.com with ESMTP; 05 Jun 2020 08:23:21 -0700 Received: from [10.249.226.228] (abudanko-mobl.ccr.corp.intel.com [10.249.226.228]) by linux.intel.com (Postfix) with ESMTP id B8D2A580569; Fri, 5 Jun 2020 08:23:18 -0700 (PDT) Subject: Re: [PATCH v5 13/13] perf record: introduce --ctl-fd[-ack] options From: Alexey Budankov To: Jiri Olsa Cc: Adrian Hunter , Andi Kleen , Arnaldo Carvalho de Melo , Namhyung Kim , Alexander Shishkin , Peter Zijlstra , Ingo Molnar , linux-kernel References: <8ffc9f9f-af58-deea-428b-f8a69004e3cb@linux.intel.com> <923c40c7-7c0b-9fad-314d-69e7acbee201@intel.com> <937c8cc1-b4c2-8531-3fa4-d0ad9df6a65f@linux.intel.com> <20200601233732.GA691017@tassilo.jf.intel.com> <1bc7c72b-9d78-5184-a27c-8025beadaaf0@linux.intel.com> <935187e8-6fc8-5f47-b88d-6e8c92a27286@intel.com> <20200605105108.GB1404794@krava> <3ac6d0b8-5fae-348f-8556-4bf7a66285f6@linux.intel.com> <20200605135743.GD1404794@krava> Organization: Intel Corp. Message-ID: <0d1d9c45-a880-9a5d-e35d-c80fb3b71eab@linux.intel.com> Date: Fri, 5 Jun 2020 18:23:17 +0300 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.8.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 05.06.2020 17:47, Alexey Budankov wrote: > > On 05.06.2020 16:57, Jiri Olsa wrote: >> On Fri, Jun 05, 2020 at 04:15:52PM +0300, Alexey Budankov wrote: >>> >>> On 05.06.2020 13:51, Jiri Olsa wrote: >>>> On Tue, Jun 02, 2020 at 04:43:58PM +0300, Adrian Hunter wrote: >>>>> On 2/06/20 12:12 pm, Alexey Budankov wrote: >>>>>> >>>>>> On 02.06.2020 11:32, Alexey Budankov wrote: >>>>>>> >>>>>>> On 02.06.2020 2:37, Andi Kleen wrote: >>>>>>>>>> or a pathname, or including also the event default of "disabled". >>>>>>>>> >>>>>>>>> For my cases conversion of pathnames into open fds belongs to external >>>>>>>>> controlling process e.g. like in the examples provided in the patch set. >>>>>>>>> Not sure about "event default of 'disabled'" >>>>>>>> >>>>>>>> It would be nicer for manual use cases if perf supported the path names >>>>>>>> directly like in Adrian's example, not needing a complex wrapper script. >>>>>>> >>>>>>> fds interface is required for VTune integration since VTune wants control >>>>>>> over files creation aside of Perf tool process. The script demonstrates >>>>>>> just one possible use case. >>>>>>> >>>>>>> Control files could easily be implemented on top of fds making open operations >>>>>>> for paths and then initializing fds. Interface below is vague and with explicit >>>>>>> options like below it could be more explicit: >>>>>>> --ctl-file /tmp/my-perf.fifo --ctl-file-ack /tmp/my-perf-ack.fifo >>>>>> >>>>>> Or even clearer: >>>>>> >>>>>> --ctl-fifo /tmp/my-perf --ctl-fifo-ack /tmp/my-perf-ack >>>>> >>>>> If people are OK with having so many options, then that is fine by me. >>>> >>>> the single option Adrian suggested seems better to me: >>>> >>>> --control >>>> --control 11 >>>> --control 11,15 >>> >>> What if a user specifies fifos named like this above, not fds? >>> >>>> --control 11,15,disabled >>>> --control 11,,disabled >>>> --control /tmp/my-perf.fifo >>>> --control /tmp/my-perf.fifo,/tmp/my-perf-ack.fifo >>> >>> What if a user wants not fifos but other type of comm channels? >>> >>>> --control /tmp/my-perf.fifo,/tmp/my-perf-ack.fifo,disabled >>>> --control /tmp/my-perf.fifo,,disabled >>>> >>>> we already support this kind of options arguments, like for --call-graph >>>> >>>> jirka >>>> >>> >>> IMHO, >>> this interface, of course, looks more compact (in amount of options) however >>> the other side it is less user friendly. One simple option for one simple >>> purpose is more convenient as for users as for developers. Also complex >>> option syntax tends to have limitations and there are probably more >>> non-obvious ones. >>> >>> Please speak up. I might have missed something meaningful. >> >> how about specify the type like: >> >> --control fd:1,2,... > > What do these ... mean? After all, if you want it this way and it now also fits my needs I could convert --ctl-fd[-ack] to --control fd:, with use cases like --control fd: and --control fd:,. Accepted? ~Alexey > >> --control fifo:/tmp/fifo1,/tmp/fifo2 >> --control xxx:.... >> >> this way we can extend the functionality in the future >> and stay backward compatible, while keeping single option > > Well, it clarifies more. However it still implicitly assumes > and requires proper ordering e.g. 1 is ctl-fd and 2 is ack-fd > and if there are some more positions there will be gaps like > --control fd:10,,something,,something ... > > Why is one single option with complex syntax more preferable > than several simple options? Also it would still consume almost > equal amount of command line space in shell. > > Thanks, > Alexey > >> >> jirka >>