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=-14.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 A3EACC433E0 for ; Fri, 25 Dec 2020 22:24:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6A4E422286 for ; Fri, 25 Dec 2020 22:24:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728681AbgLYWWP convert rfc822-to-8bit (ORCPT ); Fri, 25 Dec 2020 17:22:15 -0500 Received: from us-smtp-delivery-44.mimecast.com ([205.139.111.44]:41521 "EHLO us-smtp-delivery-44.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726737AbgLYWWP (ORCPT ); Fri, 25 Dec 2020 17:22:15 -0500 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-384-yx8-BJUjMk6W8PL0b8rqLQ-1; Fri, 25 Dec 2020 17:21:17 -0500 X-MC-Unique: yx8-BJUjMk6W8PL0b8rqLQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D664515720; Fri, 25 Dec 2020 22:21:14 +0000 (UTC) Received: from krava.redhat.com (unknown [10.40.192.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id 5175310013BD; Fri, 25 Dec 2020 22:21:10 +0000 (UTC) From: Jiri Olsa To: Arnaldo Carvalho de Melo Cc: lkml , Peter Zijlstra , Ingo Molnar , Mark Rutland , Namhyung Kim , Alexander Shishkin , Michael Petlan , Ian Rogers , Stephane Eranian , Alexei Budankov Subject: [PATCH] perf tools: Detect when pipe is passed as perf data Date: Fri, 25 Dec 2020 23:21:09 +0100 Message-Id: <20201225222109.364465-1-jolsa@kernel.org> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jolsa@kernel.org X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kernel.org Content-Transfer-Encoding: 8BIT Content-Type: text/plain; charset=WINDOWS-1252 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently we allow pipe input/output only through '-' string being passed to '-o' or '-i' options, like: # mkfifo perf.pipe # perf record --no-buffering -e 'sched:sched_switch' -o - > perf.pipe & [1] 354406 # cat perf.pipe | ./perf --no-pager script -i - | head -3 perf 354406 [000] 168190.164921: sched:sched_switch: perf:354406.. migration/0 12 [000] 168190.164928: sched:sched_switch: migration/0:.. perf 354406 [001] 168190.164981: sched:sched_switch: perf:354406.. ... This patch detects if given path is pipe and set the perf data object accordingly, so it's possible now to do above with: # mkfifo perf.pipe # perf record --no-buffering -e 'sched:sched_switch' -o perf.pipe & [1] 360188 # perf --no-pager script -i ./perf.pipe | head -3 perf 354442 [000] 168275.464895: sched:sched_switch: perf:354442.. migration/0 12 [000] 168275.464902: sched:sched_switch: migration/0:.. perf 354442 [001] 168275.464953: sched:sched_switch: perf:354442.. It's of course possible to combine any of above ways. Signed-off-by: Jiri Olsa --- tools/perf/util/data.c | 27 +++++++++++++++++++++------ 1 file changed, 21 insertions(+), 6 deletions(-) diff --git a/tools/perf/util/data.c b/tools/perf/util/data.c index f29af4fc3d09..767b6c903cf5 100644 --- a/tools/perf/util/data.c +++ b/tools/perf/util/data.c @@ -159,7 +159,7 @@ int perf_data__update_dir(struct perf_data *data) return 0; } -static bool check_pipe(struct perf_data *data) +static int check_pipe(struct perf_data *data) { struct stat st; bool is_pipe = false; @@ -172,6 +172,15 @@ static bool check_pipe(struct perf_data *data) } else { if (!strcmp(data->path, "-")) is_pipe = true; + else if (!stat(data->path, &st) && S_ISFIFO(st.st_mode)) { + int flags = perf_data__is_read(data) ? + O_RDONLY : O_WRONLY|O_CREAT|O_TRUNC; + + fd = open(data->path, flags); + if (fd < 0) + return -EINVAL; + is_pipe = true; + } } if (is_pipe) { @@ -190,7 +199,8 @@ static bool check_pipe(struct perf_data *data) } } - return data->is_pipe = is_pipe; + data->is_pipe = is_pipe; + return 0; } static int check_backup(struct perf_data *data) @@ -344,8 +354,11 @@ static int open_dir(struct perf_data *data) int perf_data__open(struct perf_data *data) { - if (check_pipe(data)) - return 0; + int err; + + err = check_pipe(data); + if (err || data->is_pipe) + return err; /* currently it allows stdio for pipe only */ data->use_stdio = false; @@ -410,8 +423,10 @@ int perf_data__switch(struct perf_data *data, { int ret; - if (check_pipe(data)) - return -EINVAL; + ret = check_pipe(data); + if (ret || data->is_pipe) + return ret; + if (perf_data__is_read(data)) return -EINVAL; -- 2.26.2