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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 CAD05C433E2 for ; Tue, 8 Sep 2020 18:39:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 883F42080C for ; Tue, 8 Sep 2020 18:39:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599590381; bh=dHp68Ju7MZ8MzQV+IYA/UvzVLU+N3F3/x1koRgcbyjA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=APN1+xU4GFoblp4oA842C9qbqPdz2j2YfN2/8dHtyNVV21H4+l8EJIf1Z//TWHkbi y4i4B8tR09ez67FbNUbi+zC8Hdl4Uo/n7YID99qBYk1TvA/UWxEZha6Hxx/t70L8eL qejUCfnxxDaSYDNw843mbfnnyPCCFlfqcYNCSQ8c= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731957AbgIHSjj (ORCPT ); Tue, 8 Sep 2020 14:39:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:56078 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731331AbgIHQJA (ORCPT ); Tue, 8 Sep 2020 12:09:00 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A89B624059; Tue, 8 Sep 2020 15:48:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1599580116; bh=dHp68Ju7MZ8MzQV+IYA/UvzVLU+N3F3/x1koRgcbyjA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FkovZfKCi8jHrdowVGRfMBwfHXkhPlvmwuyXrqhqtqDlVqsRX7zAJ81Oz5ChbOKUe E9Ue+clJmLSf9Yd1299jwXb6Igtx66/MGj0d7HuPudEcwGxLhDrCx/Hk4GM4AM3BJc M74qGmCx/NWWO09E1Jtrqzdz1qSVauTu/EH7nQuk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jesper Dangaard Brouer , Daniel Borkmann , Sasha Levin Subject: [PATCH 4.19 37/88] selftests/bpf: Fix massive output from test_maps Date: Tue, 8 Sep 2020 17:25:38 +0200 Message-Id: <20200908152222.961572365@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200908152221.082184905@linuxfoundation.org> References: <20200908152221.082184905@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jesper Dangaard Brouer [ Upstream commit fa4505675e093e895b7ec49a76d44f6b5ad9602e ] When stdout output from the selftests tool 'test_maps' gets redirected into e.g file or pipe, then the output lines increase a lot (from 21 to 33949 lines). This is caused by the printf that happens before the fork() call, and there are user-space buffered printf data that seems to be duplicated into the forked process. To fix this fflush() stdout before the fork loop in __run_parallel(). Fixes: 1a97cf1fe503 ("selftests/bpf: speedup test_maps") Signed-off-by: Jesper Dangaard Brouer Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/159842985651.1050885.2154399297503372406.stgit@firesoul Signed-off-by: Sasha Levin --- tools/testing/selftests/bpf/test_maps.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c index 9b552c0fc47db..4e202217fae10 100644 --- a/tools/testing/selftests/bpf/test_maps.c +++ b/tools/testing/selftests/bpf/test_maps.c @@ -1017,6 +1017,8 @@ static void __run_parallel(int tasks, void (*fn)(int task, void *data), pid_t pid[tasks]; int i; + fflush(stdout); + for (i = 0; i < tasks; i++) { pid[i] = fork(); if (pid[i] == 0) { -- 2.25.1