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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 CD845C004D3 for ; Mon, 22 Oct 2018 13:54:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0382E20651 for ; Mon, 22 Oct 2018 13:54:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0382E20651 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.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 S1728236AbeJVWNO (ORCPT ); Mon, 22 Oct 2018 18:13:14 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50362 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727587AbeJVWNN (ORCPT ); Mon, 22 Oct 2018 18:13:13 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id E2DC95F74A; Mon, 22 Oct 2018 13:54:32 +0000 (UTC) Received: from krava (unknown [10.43.17.150]) by smtp.corp.redhat.com (Postfix) with SMTP id B62BE608F3; Mon, 22 Oct 2018 13:54:31 +0000 (UTC) Date: Mon, 22 Oct 2018 15:54:30 +0200 From: Jiri Olsa To: Milian Wolff Cc: acme@kernel.org, jolsa@kernel.org, Linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org Subject: Re: [PATCH 2/2] perf script: flush output stream after events in verbose mode Message-ID: <20181022135430.GA2945@krava> References: <20181021191424.16183-1-milian.wolff@kdab.com> <4444017.LnbBPIbh24@agathebauer> <20181022101618.GH2452@krava> <1755624.MxyOU8z0WO@agathebauer> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1755624.MxyOU8z0WO@agathebauer> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.39]); Mon, 22 Oct 2018 13:54:33 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 22, 2018 at 12:38:57PM +0200, Milian Wolff wrote: SNIP > > > > > diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c > > > > > index bd468b90801b..ca09b7d2adb7 100644 > > > > > --- a/tools/perf/builtin-script.c > > > > > +++ b/tools/perf/builtin-script.c > > > > > @@ -1737,6 +1737,9 @@ static void process_event(struct perf_script > > > > > *script, > > > > > > > > > > if (PRINT_FIELD(METRIC)) > > > > > > > > > > perf_sample__fprint_metric(script, thread, evsel, > sample, fp); > > > > > > > > > > + > > > > > + if (verbose) > > > > > + fflush(fp); > > > > > > > > should we call fflush(NULL) to dump all the streams? > > > > > > > > the verbose goes to stderr and fp seems to be stdout byt default > > > > > > stderr isn't buffered, so we don't need to flush it. So personally, I > > > don't > > > see a need to dump all streams - fp should be enough? Can you maybe > > > explain > > > where it would be required to flush more buffers? > > > > hum, did not know stderr wasn't buffer > > > > I think there's perf script feature to store the events data to > > separate files per each event.. but I guess we don't need to > > flush them.. we just need to have stdout and stderr in sync IIUC > > Exactly, and that's achieved with this patch form what I see :) Or should we > maybe instead call > > setbuf(fp, NULL); > > in verbose mode? I think your solution is ok Acked-by: Jiri Olsa thanks, jirka