From patchwork Wed Oct 5 01:39:33 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shaopeng Tan X-Patchwork-Id: 12998819 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 BD442C433FE for ; Wed, 5 Oct 2022 01:44:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229760AbiJEBoy (ORCPT ); Tue, 4 Oct 2022 21:44:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229772AbiJEBox (ORCPT ); Tue, 4 Oct 2022 21:44:53 -0400 Received: from esa11.hc1455-7.c3s2.iphmx.com (esa11.hc1455-7.c3s2.iphmx.com [207.54.90.137]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C859912D14; Tue, 4 Oct 2022 18:44:49 -0700 (PDT) X-IronPort-AV: E=McAfee;i="6500,9779,10490"; a="70500946" X-IronPort-AV: E=Sophos;i="5.95,159,1661785200"; d="scan'208";a="70500946" Received: from unknown (HELO oym-r4.gw.nic.fujitsu.com) ([210.162.30.92]) by esa11.hc1455-7.c3s2.iphmx.com with ESMTP; 05 Oct 2022 10:43:43 +0900 Received: from oym-m1.gw.nic.fujitsu.com (oym-nat-oym-m1.gw.nic.fujitsu.com [192.168.87.58]) by oym-r4.gw.nic.fujitsu.com (Postfix) with ESMTP id 128CADA68A; Wed, 5 Oct 2022 10:43:42 +0900 (JST) Received: from yto-om1.fujitsu.com (yto-om1.o.css.fujitsu.com [10.128.89.162]) by oym-m1.gw.nic.fujitsu.com (Postfix) with ESMTP id 4F806D9940; Wed, 5 Oct 2022 10:43:41 +0900 (JST) Received: from cn-r05-10.example.com (n3235113.np.ts.nmh.cs.fujitsu.co.jp [10.123.235.113]) by yto-om1.fujitsu.com (Postfix) with ESMTP id 1C0F0405D4705; Wed, 5 Oct 2022 10:43:41 +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 v2 4/4] selftests/resctrl: Flush stdout file buffer before executing fork() Date: Wed, 5 Oct 2022 10:39:33 +0900 Message-Id: <20221005013933.1486054-5-tan.shaopeng@jp.fujitsu.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20221005013933.1486054-1-tan.shaopeng@jp.fujitsu.com> References: <20221005013933.1486054-1-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 --- 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 6f543e470ad4..c7447cd2a25f 100644 --- a/tools/testing/selftests/resctrl/resctrlfs.c +++ b/tools/testing/selftests/resctrl/resctrlfs.c @@ -676,6 +676,7 @@ int filter_dmesg(void) perror("pipe"); return ret; } + fflush(stdout); pid = fork(); if (pid == 0) { close(pipefds[0]);