From patchwork Tue Jan 15 22:54:47 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stanislav Fomichev X-Patchwork-Id: 1025533 X-Patchwork-Delegate: bpf@iogearbox.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@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=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=google.com header.i=@google.com header.b="MTDEN8JS"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 43fQdv574Mz9sD4 for ; Wed, 16 Jan 2019 09:54:59 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2403753AbfAOWy6 (ORCPT ); Tue, 15 Jan 2019 17:54:58 -0500 Received: from mail-pl1-f201.google.com ([209.85.214.201]:45564 "EHLO mail-pl1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391269AbfAOWy4 (ORCPT ); Tue, 15 Jan 2019 17:54:56 -0500 Received: by mail-pl1-f201.google.com with SMTP id h10so2562549plk.12 for ; Tue, 15 Jan 2019 14:54:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=O9lDcchyIR0ULzkPipbF9IITLIhRh87laB/Yzj0CKko=; b=MTDEN8JSo6m54iDzwj/VGM4Nl2Gi51trQYVREDqndh2wMKh7DQHckWZofp6dN8xNO7 rAbCjjcodAdaSt7iiyrCsLunyDgyfspGp1Y40NCqFdFhtesCyG9NFvxYGpGW0TrQ+jvD xFnARCJ7S0sLxehwGlLbeNrmnZH1k65QjHr9moJyN0fpj4NXxX+/cU1nHtW8tLbXX4UB XnNfEI1ourHW0n01wcO1pneJhDFq0r9nfoVFOufJOAbMl0zxU63gqrESPGBno16Y+TXO sEUbXrk1hWFMOwL78QMXrxY3RSLhFZoxonUktvusmvJo4Jxedl72u4rCy97GADffYvP/ RHkg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=O9lDcchyIR0ULzkPipbF9IITLIhRh87laB/Yzj0CKko=; b=TGI+EHhsA4gaZrHeskkl/geZmDS2cg76gGGCfAtini2TDdY3IDUaNDgAT2V9N2XkY6 VxmAZgfUm6eq8iWgdhqbVOPuDv6eRdQnM5kQ1lorAqBpd/p4fk8e5O/jV/UvnpsbDMqe xx7chSJ2coMBZrfjUxMNzFp4WkFK531fBdB7BxDiONkijLlap2DSJVF5a84gByp9Qfj9 cLg0kH5DBk/iiqZRYZ3L585ikNJh3c0XgORYXc21MNu+No5XU23W/fF7Ty5UuDEhNkZZ jF2klfN41/VdFUX6/DfkAHggE7Epv19qf10QNo7rnJJL10XhmUgME8jdtpSkMsKvJi+V Cy3A== X-Gm-Message-State: AJcUukca0ChLpYzyAZuENAO/eYH4VeHOmNYREV8NAqeIWORS/1rWB7Q/ e/UdOuODofu8pE61XKa3ZSXz0OGla0adkT59DDv6ogPQqKFFZh1SgePLWIBWcY7B1QbOsxtUjTG kZp2MPC2foKwiYDYk0ik6TJnrHOjQW00muePV1dO10HoXP7MMdr9OFw== X-Google-Smtp-Source: ALg8bN6M5fxBo2NaKv6qlGtnFfDBNu4bk9dgj7A2mkuyMF9Q/VtPU1UdEp+ucSM8aFjV8Ww6TkRDp88= X-Received: by 2002:a17:902:e002:: with SMTP id ca2mr1854403plb.91.1547592896069; Tue, 15 Jan 2019 14:54:56 -0800 (PST) Date: Tue, 15 Jan 2019 14:54:47 -0800 In-Reply-To: <20190115225447.245788-1-sdf@google.com> Message-Id: <20190115225447.245788-3-sdf@google.com> Mime-Version: 1.0 References: <20190115225447.245788-1-sdf@google.com> X-Mailer: git-send-email 2.20.1.97.g81188d93c3-goog Subject: [PATCH bpf 3/3] selftests/bpf: retry tests that expect build-id From: Stanislav Fomichev To: netdev@vger.kernel.org Cc: davem@davemloft.net, ast@kernel.org, daniel@iogearbox.net, songliubraving@fb.com, Stanislav Fomichev Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org While running test_progs in a loop I found out that I'm sometimes hitting "Didn't find expected build ID from the map" error. Looking at stack_map_get_build_id_offset() it seems that it is racy (by design) and can sometimes return BPF_STACK_BUILD_ID_IP (i.e. can't trylock current->mm->mmap_sem). Let's retry this test a single time. Fixes: 13790d1cc72c ("bpf: add selftest for stackmap with build_id in NMI context") Signed-off-by: Stanislav Fomichev Acked-by: Song Liu --- tools/testing/selftests/bpf/test_progs.c | 30 ++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c index 126fc624290d..25f0083a9b2e 100644 --- a/tools/testing/selftests/bpf/test_progs.c +++ b/tools/testing/selftests/bpf/test_progs.c @@ -1188,7 +1188,9 @@ static void test_stacktrace_build_id(void) int i, j; struct bpf_stack_build_id id_offs[PERF_MAX_STACK_DEPTH]; int build_id_matches = 0; + int retry = 1; +retry: err = bpf_prog_load(file, BPF_PROG_TYPE_TRACEPOINT, &obj, &prog_fd); if (CHECK(err, "prog_load", "err %d errno %d\n", err, errno)) goto out; @@ -1301,6 +1303,19 @@ static void test_stacktrace_build_id(void) previous_key = key; } while (bpf_map_get_next_key(stackmap_fd, &previous_key, &key) == 0); + /* stack_map_get_build_id_offset() is racy and sometimes can return + * BPF_STACK_BUILD_ID_IP instead of BPF_STACK_BUILD_ID_VALID; + * try it one more time. + */ + if (build_id_matches < 1 && retry--) { + ioctl(pmu_fd, PERF_EVENT_IOC_DISABLE); + close(pmu_fd); + bpf_object__close(obj); + printf("%s:WARN:Didn't find expected build ID from the map, retrying\n", + __func__); + goto retry; + } + if (CHECK(build_id_matches < 1, "build id match", "Didn't find expected build ID from the map\n")) goto disable_pmu; @@ -1341,7 +1356,9 @@ static void test_stacktrace_build_id_nmi(void) int i, j; struct bpf_stack_build_id id_offs[PERF_MAX_STACK_DEPTH]; int build_id_matches = 0; + int retry = 1; +retry: err = bpf_prog_load(file, BPF_PROG_TYPE_PERF_EVENT, &obj, &prog_fd); if (CHECK(err, "prog_load", "err %d errno %d\n", err, errno)) return; @@ -1436,6 +1453,19 @@ static void test_stacktrace_build_id_nmi(void) previous_key = key; } while (bpf_map_get_next_key(stackmap_fd, &previous_key, &key) == 0); + /* stack_map_get_build_id_offset() is racy and sometimes can return + * BPF_STACK_BUILD_ID_IP instead of BPF_STACK_BUILD_ID_VALID; + * try it one more time. + */ + if (build_id_matches < 1 && retry--) { + ioctl(pmu_fd, PERF_EVENT_IOC_DISABLE); + close(pmu_fd); + bpf_object__close(obj); + printf("%s:WARN:Didn't find expected build ID from the map, retrying\n", + __func__); + goto retry; + } + if (CHECK(build_id_matches < 1, "build id match", "Didn't find expected build ID from the map\n")) goto disable_pmu;