From patchwork Tue Nov 1 09:43:39 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shaopeng Tan X-Patchwork-Id: 13026826 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 607E0FA373D for ; Tue, 1 Nov 2022 09:49:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230400AbiKAJtY (ORCPT ); Tue, 1 Nov 2022 05:49:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55588 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229872AbiKAJsx (ORCPT ); Tue, 1 Nov 2022 05:48:53 -0400 Received: from esa2.hc1455-7.c3s2.iphmx.com (esa2.hc1455-7.c3s2.iphmx.com [207.54.90.48]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 073EF2EA; Tue, 1 Nov 2022 02:48:51 -0700 (PDT) X-IronPort-AV: E=McAfee;i="6500,9779,10517"; a="94348495" X-IronPort-AV: E=Sophos;i="5.95,230,1661785200"; d="scan'208";a="94348495" Received: from unknown (HELO oym-r4.gw.nic.fujitsu.com) ([210.162.30.92]) by esa2.hc1455-7.c3s2.iphmx.com with ESMTP; 01 Nov 2022 18:48:50 +0900 Received: from oym-m4.gw.nic.fujitsu.com (oym-nat-oym-m4.gw.nic.fujitsu.com [192.168.87.61]) by oym-r4.gw.nic.fujitsu.com (Postfix) with ESMTP id 689A810E8C; Tue, 1 Nov 2022 18:48:48 +0900 (JST) Received: from oym-om4.fujitsu.com (oym-om4.o.css.fujitsu.com [10.85.58.164]) by oym-m4.gw.nic.fujitsu.com (Postfix) with ESMTP id 7F1C3D55EB; Tue, 1 Nov 2022 18:48:47 +0900 (JST) Received: from cn-r05-10.example.com (n3235113.np.ts.nmh.cs.fujitsu.co.jp [10.123.235.113]) by oym-om4.fujitsu.com (Postfix) with ESMTP id 6B43940164011; Tue, 1 Nov 2022 18:48:47 +0900 (JST) From: Shaopeng Tan To: Fenghua Yu , Reinette Chatre , Shuah Khan Cc: linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, tan.shaopeng@jp.fujitsu.com Subject: [PATCH v3 3/5] selftests/resctrl: Flush stdout file buffer before executing fork() Date: Tue, 1 Nov 2022 18:43:39 +0900 Message-Id: <20221101094341.3383073-4-tan.shaopeng@jp.fujitsu.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20221101094341.3383073-1-tan.shaopeng@jp.fujitsu.com> References: <20221101094341.3383073-1-tan.shaopeng@jp.fujitsu.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org When a process has buffered output, a child process created by fork() will also copy buffered output. When using kselftest framework, the output (resctrl test result message) will be printed multiple times. Add fflush() to flush out the buffered output before executing fork(). Reviewed-by: Reinette Chatre Signed-off-by: Shaopeng Tan Reviewed-by: Shuah Khan --- tools/testing/selftests/resctrl/cat_test.c | 1 + tools/testing/selftests/resctrl/resctrl_val.c | 1 + tools/testing/selftests/resctrl/resctrlfs.c | 1 + 3 files changed, 3 insertions(+) diff --git a/tools/testing/selftests/resctrl/cat_test.c b/tools/testing/selftests/resctrl/cat_test.c index 1c5e90c63254..6a8306b0a109 100644 --- a/tools/testing/selftests/resctrl/cat_test.c +++ b/tools/testing/selftests/resctrl/cat_test.c @@ -167,6 +167,7 @@ int cat_perf_miss_val(int cpu_no, int n, char *cache_type) return errno; } + fflush(stdout); bm_pid = fork(); /* Set param values for child thread which will be allocated bitmask diff --git a/tools/testing/selftests/resctrl/resctrl_val.c b/tools/testing/selftests/resctrl/resctrl_val.c index b32b96356ec7..6948843bf995 100644 --- a/tools/testing/selftests/resctrl/resctrl_val.c +++ b/tools/testing/selftests/resctrl/resctrl_val.c @@ -629,6 +629,7 @@ int resctrl_val(char **benchmark_cmd, struct resctrl_val_param *param) * Fork to start benchmark, save child's pid so that it can be killed * when needed */ + fflush(stdout); bm_pid = fork(); if (bm_pid == -1) { perror("# Unable to fork"); diff --git a/tools/testing/selftests/resctrl/resctrlfs.c b/tools/testing/selftests/resctrl/resctrlfs.c index 8546bc9f1786..d95688298469 100644 --- a/tools/testing/selftests/resctrl/resctrlfs.c +++ b/tools/testing/selftests/resctrl/resctrlfs.c @@ -678,6 +678,7 @@ int filter_dmesg(void) perror("pipe"); return ret; } + fflush(stdout); pid = fork(); if (pid == 0) { close(pipefds[0]);