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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 autolearn=ham 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 F3FE6C433DF for ; Wed, 13 May 2020 20:16:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7CD31206A5 for ; Wed, 13 May 2020 20:16:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390893AbgEMUQf (ORCPT ); Wed, 13 May 2020 16:16:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:41422 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390883AbgEMUQf (ORCPT ); Wed, 13 May 2020 16:16:35 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5F7132065C; Wed, 13 May 2020 20:16:35 +0000 (UTC) Date: Wed, 13 May 2020 16:16:33 -0400 From: Steven Rostedt To: Bijan Tabatabai Cc: linux-trace-devel@vger.kernel.org, Bijan Tabatabai Subject: Re: [PATCH v3] trace-cmd: Stop recording when processes traced with -P exit Message-ID: <20200513161633.0ef67ea2@gandalf.local.home> In-Reply-To: <20200513170529.22605-1-bijan311@gmail.com> References: <20200513170529.22605-1-bijan311@gmail.com> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-trace-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-trace-devel@vger.kernel.org On Wed, 13 May 2020 12:05:29 -0500 Bijan Tabatabai wrote: > From: Bijan Tabatabai > > When the -F flag is used in trace-cmd record, trace-cmd stops recording > when the executable it is tracing terminates. > This patch makes the -P flag act similarly. > > Signed-off-by: Bijan Tabatabai > --- > This patch has changed to use the pidfd interface to determine if a process > has ended. > It also has changed to work with the patch "trace-cmd: Handle filtered PIDs per > ftarce instance" (5502bcef0f962cda). > --- > tracecmd/include/trace-local.h | 2 + > tracecmd/trace-record.c | 84 ++++++++++++++++++++++++++++++++++ > 2 files changed, 86 insertions(+) > Nice! Although I just tried it out and noticed that if I run the following command: # sleep 20& sleep 50& [1] 2216 [2] 2218 # trace-cmd record -e sched -P 2216 -B foo -e all -P 2218 It will exit out after the first sleep (20 second) and before the second is done. It appears to exit as soon as the first process is finished. We should want to wait till the last one is finished. -- Steve