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=-8.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS,USER_IN_DEF_DKIM_WL 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 2E51EC6787C for ; Fri, 12 Oct 2018 21:26:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D7DC120868 for ; Fri, 12 Oct 2018 21:26:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="EiZ592V3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D7DC120868 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726281AbeJMFAp (ORCPT ); Sat, 13 Oct 2018 01:00:45 -0400 Received: from mail-wr1-f47.google.com ([209.85.221.47]:37596 "EHLO mail-wr1-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726125AbeJMFAp (ORCPT ); Sat, 13 Oct 2018 01:00:45 -0400 Received: by mail-wr1-f47.google.com with SMTP id y11-v6so14808110wrd.4 for ; Fri, 12 Oct 2018 14:26:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:from:date:message-id:subject:to:cc; bh=Ky/hwcktm81qh6cVpdbTrJeL1bzyNIt4g7dMkNUjmuY=; b=EiZ592V3M8YCvv8yLdOkXjOkn8HMy/HNBRqw0RyLq1oxSSuLiktR4pKKUvMb9yAoRo dtn1maFkI9OiZt0/HLJ39W6qnw39mX4LV/97KWORIQWzweFeSXeTvFmEfd3kRcIcQjPM H6Ch7C+JQIvJToktehOEnu1ery7V2khixAE5uvK/3eYZVupS77eRvPVV05LHrUKJVAsy CiAbQbr8aq6CRB/aAPlM/tQfy2TccrwZe0fhDNWWKIDUKzt6Ow1kmY09FW3Z4rLzwbBk ZPj63L4to01P3v60BiyMfnT+o+LeEBFA4aC6gjVOsCWKc4x6NkzTN5ALReoYjq1I1S6T 7F8A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to:cc; bh=Ky/hwcktm81qh6cVpdbTrJeL1bzyNIt4g7dMkNUjmuY=; b=FON1EnGvPToflocBF9qQNJnGDQ5z855ixGpwgb5BQVboGp4dyEq92LOwJv0uQ+cfmD NiY4uROz561OJe5WdPrK1NCx4nn9tucUeroypHDrbHD6eygEQvPd8ebxkyQ2Mdd+LLW6 wqt0kZmbkrDjDDy1z7vkTTQ+ZH7a004tMXGUgQKiEPXu9sHxg4vXlkyLSvjib9UgCXv8 40XaqsizVm7roJMIOLU8Aegl2lnxfx+83mh6e8KbsQv7s2QwLnsPAB7oXar9nbOnRYOi a4b20gYrHL5uO7NaHwgTRrXcDL05OO2K5jD9NoZZi2y6AT4KmPl4iVR2HoJAwDQK3q4M Tm4Q== X-Gm-Message-State: ABuFfojW0MgCfbgEIHU3SWo/pLJrkxU4h9sH3YN3Xs0dGU0WNy1lkenP DlzSmPm06JLdYP67TeD/HKzspZwxmmlLG9Y7a0WORjBIfK0= X-Google-Smtp-Source: ACcGV61f+kDYLAJQVlmF9rblF+fotcHvRrAgHXZeY1SHEfOq0oqOs9rMxfFT0lCRBAxmkIklo9bCPj8dCCNe7Nn9z54= X-Received: by 2002:adf:ed06:: with SMTP id a6-v6mr6194417wro.262.1539379580663; Fri, 12 Oct 2018 14:26:20 -0700 (PDT) MIME-Version: 1.0 From: Stephane Eranian Date: Fri, 12 Oct 2018 14:26:09 -0700 Message-ID: Subject: [BUG] perf stat: hangs with -p and process completes To: Arnaldo Carvalho de Melo Cc: Jiri Olsa , LKML Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, I am running into a perf stat issue with the -p option which allows you to attach to a running process. If that process happens to terminate while under monitoring perf hangs in there and never terminates. The proper behavior would be to stop. I can see the issue in that the attached process is not a child, so wait() would not work. To reproduce: $ sleep 10 & $ perf stat -p $! doing the same with perf record works, so there is a solution to this problem.