From patchwork Fri Aug 16 17:08:25 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Petar Penkov X-Patchwork-Id: 1148367 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: incoming-bpf@patchwork.ozlabs.org Delivered-To: patchwork-incoming-bpf@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=bpf-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=gmail.com header.i=@gmail.com header.b="bouj+2M9"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 4698sp5SQ9z9sN1 for ; Sat, 17 Aug 2019 03:08:30 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727224AbfHPRI3 (ORCPT ); Fri, 16 Aug 2019 13:08:29 -0400 Received: from mail-pl1-f194.google.com ([209.85.214.194]:37865 "EHLO mail-pl1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726469AbfHPRI3 (ORCPT ); Fri, 16 Aug 2019 13:08:29 -0400 Received: by mail-pl1-f194.google.com with SMTP id bj8so2691286plb.4; Fri, 16 Aug 2019 10:08:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=VztW51XA4vx8PX2Mz/t0kTb9/SRjKZo7CzRhZxpblX0=; b=bouj+2M9urBXvFJ5K/O+dTYmgXzSr+S/Ik2NQmrSHdA+X8BQNiSjgUoZxa8GiMPriu CBgo/N1EhJx+V94t9m/R1qSNOn+eEi+t6k9/pADkP6PE+aKyKatcgNzMhmnPTWidKCFZ WgFq87i27xHJ/ELaXrcmM62qmDTxZMDFsPbY/FB26AvFcPIA9dlLpTyFb9jA0G9FBXb0 v2+j5KYKykm3C47py0M1pPrqmWk+dQNT96uUiOKVqkh5h+xFS5xsJ5HouGhvEsDZghJ3 PmKgk6Q7KAzZZKhwsXtHTZTSpYi/LgjowIIr2qxwlsKOIuOPpkPm6Mr1bEnviZjUJyU1 l2UQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=VztW51XA4vx8PX2Mz/t0kTb9/SRjKZo7CzRhZxpblX0=; b=Q4Q4pxH9BHOo5oxqV/4+sM52fH7+M3inmeMYZkxalzTTCesVV+evmCXjkeMTX9hJJw zaaJI1Qa3tcBBWY0OBZAz/jFhTr+HaUMG3GIPbBgSC+/p7ry1K8L64HW+Jf6b1dQA/eY EYmuZaWrro1Ela2VaROi9MWLiANJmXx/7+4ZFU8hWogndemzQMhP/vQWvuqV+KM5NAAa J7Zf8H1oFeBb8ATHXq+iAWyMuXb1u9n8JLiAgEM2PA+4OmHVGDa68CcKOzqJckvcNi34 HSezN2R7qNeaxcCitSsEq9aWwD/zwEvQu9o6Tq92HOeTu5cBf6VyUowPl0TQqgcmL3eV zpFg== X-Gm-Message-State: APjAAAXX2hF+6kdE5rGpNtbM1+6E4hI/0oLGOiSWusobwpV5Rdkwe5Xb 0mR4hTQzisMKFPW9tsbl2JWubab+ X-Google-Smtp-Source: APXvYqwIeDQKZJbyVJjTXgFuAPjG2NNPGJortHgJf9lEnuPVu86cfNOCfw67hVgMbc52foDzfAWGPw== X-Received: by 2002:a17:902:1107:: with SMTP id d7mr10149403pla.184.1565975308839; Fri, 16 Aug 2019 10:08:28 -0700 (PDT) Received: from ppenkov.svl.corp.google.com ([2620:15c:2c4:201:7bd4:4f27:abe4:d695]) by smtp.gmail.com with ESMTPSA id e13sm7194113pff.181.2019.08.16.10.08.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 16 Aug 2019 10:08:28 -0700 (PDT) From: Petar Penkov To: netdev@vger.kernel.org, bpf@vger.kernel.org Cc: davem@davemloft.net, ast@kernel.org, daniel@iogearbox.net, sdf@google.com, Petar Penkov Subject: [bpf-next,v2] selftests/bpf: fix race in test_tcp_rtt test Date: Fri, 16 Aug 2019 10:08:25 -0700 Message-Id: <20190816170825.22500-1-ppenkov.kernel@gmail.com> X-Mailer: git-send-email 2.23.0.rc1.153.gdeed80330f-goog MIME-Version: 1.0 Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org From: Petar Penkov There is a race in this test between receiving the ACK for the single-byte packet sent in the test, and reading the values from the map. This patch fixes this by having the client wait until there are no more unacknowledged packets. Before: for i in {1..1000}; do ../net/in_netns.sh ./test_tcp_rtt; \ done | grep -c PASSED < trimmed error messages > 993 After: for i in {1..10000}; do ../net/in_netns.sh ./test_tcp_rtt; \ done | grep -c PASSED 10000 Fixes: b55873984dab ("selftests/bpf: test BPF_SOCK_OPS_RTT_CB") Signed-off-by: Petar Penkov Reviewed-by: Stanislav Fomichev --- tools/testing/selftests/bpf/test_tcp_rtt.c | 31 ++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/tools/testing/selftests/bpf/test_tcp_rtt.c b/tools/testing/selftests/bpf/test_tcp_rtt.c index 90c3862f74a8..93916a69823e 100644 --- a/tools/testing/selftests/bpf/test_tcp_rtt.c +++ b/tools/testing/selftests/bpf/test_tcp_rtt.c @@ -6,6 +6,7 @@ #include #include #include +#include #include #include @@ -34,6 +35,30 @@ static void send_byte(int fd) error(1, errno, "Failed to send single byte"); } +static int wait_for_ack(int fd, int retries) +{ + struct tcp_info info; + socklen_t optlen; + int i, err; + + for (i = 0; i < retries; i++) { + optlen = sizeof(info); + err = getsockopt(fd, SOL_TCP, TCP_INFO, &info, &optlen); + if (err < 0) { + log_err("Failed to lookup TCP stats"); + return err; + } + + if (info.tcpi_unacked == 0) + return 0; + + usleep(10); + } + + log_err("Did not receive ACK"); + return -1; +} + static int verify_sk(int map_fd, int client_fd, const char *msg, __u32 invoked, __u32 dsack_dups, __u32 delivered, __u32 delivered_ce, __u32 icsk_retransmits) @@ -149,6 +174,11 @@ static int run_test(int cgroup_fd, int server_fd) /*icsk_retransmits=*/0); send_byte(client_fd); + if (wait_for_ack(client_fd, 100) < 0) { + err = -1; + goto close_client_fd; + } + err += verify_sk(map_fd, client_fd, "first payload byte", /*invoked=*/2, @@ -157,6 +187,7 @@ static int run_test(int cgroup_fd, int server_fd) /*delivered_ce=*/0, /*icsk_retransmits=*/0); +close_client_fd: close(client_fd); close_bpf_object: