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=-7.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,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 A7A98C433E3 for ; Thu, 6 Aug 2020 11:04:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9925E22CAE for ; Thu, 6 Aug 2020 11:04:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728159AbgHFGPu (ORCPT ); Thu, 6 Aug 2020 02:15:50 -0400 Received: from mga12.intel.com ([192.55.52.136]:13679 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727977AbgHFGPt (ORCPT ); Thu, 6 Aug 2020 02:15:49 -0400 IronPort-SDR: FzdIOrhCEVJEVNStAXUSbqNDmuUoFPCO0ug62Gjo8+vkNA57+7+1tXqHeZp6DfwkVDcNaYfBCH lU2o+tXvlsYQ== X-IronPort-AV: E=McAfee;i="6000,8403,9704"; a="132286575" X-IronPort-AV: E=Sophos;i="5.75,440,1589266800"; d="scan'208";a="132286575" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Aug 2020 23:15:34 -0700 IronPort-SDR: psBcpFRPS/T1+BeZPwSHC2pI4x8dzWgV9wzmPm9RIIyirra8V4qbeojVA2SfwcemEaOeSte8xa PE0iydH2NRzw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,440,1589266800"; d="scan'208";a="493561482" Received: from ahunter-desktop.fi.intel.com (HELO [10.237.72.73]) ([10.237.72.73]) by fmsmga005.fm.intel.com with ESMTP; 05 Aug 2020 23:15:32 -0700 Subject: Re: [PATCH 0/2] perf: Allow closing siblings' file descriptors To: Alexander Shishkin , Peter Zijlstra , Arnaldo Carvalho de Melo Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Jiri Olsa , alexey.budankov@linux.intel.com References: <20200708151635.81239-1-alexander.shishkin@linux.intel.com> From: Adrian Hunter Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Message-ID: <32ad7700-3d4e-6c20-31c9-8b002fea5cbc@intel.com> Date: Thu, 6 Aug 2020 09:15:08 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20200708151635.81239-1-alexander.shishkin@linux.intel.com> 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 8/07/20 6:16 pm, Alexander Shishkin wrote: > Hi guys, > > I've been looking at reducing the number of open file descriptors per perf > session. If we retain one descriptor per event, in a large group they add > up. At the same time, we're not actually using them for anything after the > SET_OUTPUT and maybe SET_FILTER ioctls. So, this series is a stab at that. I am wondering if instead we should be looking at creating a kernel API that allows associating a multitude of tracepoints with a single event. Thoughts anyone?