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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 EAE65C2B9F4 for ; Mon, 28 Jun 2021 09:19:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CEAD9619A0 for ; Mon, 28 Jun 2021 09:19:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232518AbhF1JVt (ORCPT ); Mon, 28 Jun 2021 05:21:49 -0400 Received: from szxga02-in.huawei.com ([45.249.212.188]:5923 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232200AbhF1JVq (ORCPT ); Mon, 28 Jun 2021 05:21:46 -0400 Received: from dggeme766-chm.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4GD25p5Czlz75DV; Mon, 28 Jun 2021 17:15:58 +0800 (CST) Received: from huawei.com (10.175.104.82) by dggeme766-chm.china.huawei.com (10.3.19.112) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2176.2; Mon, 28 Jun 2021 17:19:15 +0800 From: Wang Hai To: , , , , , , , , , , , , , , CC: , , Subject: [PATCH bpf] samples/bpf: Fix xdpsock with '-M' parameter missing unload process Date: Mon, 28 Jun 2021 17:18:15 +0800 Message-ID: <20210628091815.2373487-1-wanghai38@huawei.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [10.175.104.82] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggeme766-chm.china.huawei.com (10.3.19.112) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Execute the following command and exit, then execute it again, the following error will be reported. $ sudo ./samples/bpf/xdpsock -i ens4f2 -M ^C $ sudo ./samples/bpf/xdpsock -i ens4f2 -M libbpf: elf: skipping unrecognized data section(16) .eh_frame libbpf: elf: skipping relo section(17) .rel.eh_frame for section(16) .eh_frame libbpf: Kernel error message: XDP program already attached ERROR: link set xdp fd failed commit c9d27c9e8dc7 ("samples: bpf: Do not unload prog within xdpsock") removed the unload prog code because of the presence of bpf_link. This is fine if XDP_SHARED_UMEM is disable, but if it is enable, unload prog is still needed. Fixes: c9d27c9e8dc7 ("samples: bpf: Do not unload prog within xdpsock") Signed-off-by: Wang Hai --- samples/bpf/xdpsock_user.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) diff --git a/samples/bpf/xdpsock_user.c b/samples/bpf/xdpsock_user.c index 53e300f860bb..33d0bdebbed8 100644 --- a/samples/bpf/xdpsock_user.c +++ b/samples/bpf/xdpsock_user.c @@ -96,6 +96,7 @@ static int opt_xsk_frame_size = XSK_UMEM__DEFAULT_FRAME_SIZE; static int opt_timeout = 1000; static bool opt_need_wakeup = true; static u32 opt_num_xsks = 1; +static u32 prog_id; static bool opt_busy_poll; static bool opt_reduced_cap; @@ -461,6 +462,23 @@ static void *poller(void *arg) return NULL; } +static void remove_xdp_program(void) +{ + u32 curr_prog_id = 0; + + if (bpf_get_link_xdp_id(opt_ifindex, &curr_prog_id, opt_xdp_flags)) { + printf("bpf_get_link_xdp_id failed\n"); + exit(EXIT_FAILURE); + } + + if (prog_id == curr_prog_id) + bpf_set_link_xdp_fd(opt_ifindex, -1, opt_xdp_flags); + else if (!curr_prog_id) + printf("couldn't find a prog id on a given interface\n"); + else + printf("program on interface changed, not removing\n"); +} + static void int_exit(int sig) { benchmark_done = true; @@ -471,6 +489,9 @@ static void __exit_with_error(int error, const char *file, const char *func, { fprintf(stderr, "%s:%s:%i: errno: %d/\"%s\"\n", file, func, line, error, strerror(error)); + + if (opt_num_xsks > 1) + remove_xdp_program(); exit(EXIT_FAILURE); } @@ -490,6 +511,9 @@ static void xdpsock_cleanup(void) if (write(sock, &cmd, sizeof(int)) < 0) exit_with_error(errno); } + + if (opt_num_xsks > 1) + remove_xdp_program(); } static void swap_mac_addresses(void *data) @@ -857,6 +881,10 @@ static struct xsk_socket_info *xsk_configure_socket(struct xsk_umem_info *umem, if (ret) exit_with_error(-ret); + ret = bpf_get_link_xdp_id(opt_ifindex, &prog_id, opt_xdp_flags); + if (ret) + exit_with_error(-ret); + xsk->app_stats.rx_empty_polls = 0; xsk->app_stats.fill_fail_polls = 0; xsk->app_stats.copy_tx_sendtos = 0; -- 2.17.1