From patchwork Thu Mar 10 08:22:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Namhyung Kim X-Patchwork-Id: 12776023 X-Patchwork-Delegate: bpf@iogearbox.net 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 C4967C4332F for ; Thu, 10 Mar 2022 08:22:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240278AbiCJIXM (ORCPT ); Thu, 10 Mar 2022 03:23:12 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53718 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234558AbiCJIXK (ORCPT ); Thu, 10 Mar 2022 03:23:10 -0500 Received: from mail-pj1-x102c.google.com (mail-pj1-x102c.google.com [IPv6:2607:f8b0:4864:20::102c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4C15D1301B6; Thu, 10 Mar 2022 00:22:10 -0800 (PST) Received: by mail-pj1-x102c.google.com with SMTP id mm23-20020a17090b359700b001bfceefd8c6so1339992pjb.3; Thu, 10 Mar 2022 00:22:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=sender:from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=z/Mr8oh0sWKEm17KedkzMdcKpYvzoba3uTd2uHZZr9s=; b=X5ihtfVuum0YUKHMU2jEqc/tEzjv6a/y4+REtlgaXQECTGRJCtu/aJJcsq4m7/KfJK UMf4hBdUYJGwVdbYQU94a57SU+/YGmMW5CpdGa+K+enoInnOnlkuQh3oKmJpphJLPZIl g6wHG7Gb7E38d32RU4uxaz0ZXrnkuXDBBwUqkvhJdDUvd92wYPEmD1j8chbQ4sBo78xS +uy4b2cX5ouWwTKYhmfgqn6lWt88VxBQcyZ5pzEofdgRvdjJx0R5iv4xvk6HweHwxP8R L/mhBMQcw/f/ODTz0BevBtf7MG6muzgCjI3QRjpWzHLkYgayzOmhnQDnxJRKbAmQYIn7 wF2g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:sender:from:to:cc:subject:date:message-id :in-reply-to:references:mime-version:content-transfer-encoding; bh=z/Mr8oh0sWKEm17KedkzMdcKpYvzoba3uTd2uHZZr9s=; b=Jr5vYbi+27vFnlf0Hpg+G1x5Y3PgAUo5gsbVD7pSdjGH12XqjjioGH1YnWJgcyMtZG f7WkA1qnv80bxblPv9R7E7Khe+q+ZLpnhRBBlJfwk72exXS91rbLUDnsvHIznrmQWELF QFQRw9kL9jhhndkrXV/tt5gPon71dfv/xQb/0n1N8Wxz2kIX23H49jbg5Oow/bLSnAcM DYp33yAbnxC3sqFkRfFsGMl3DEPJGQB8uBiTMGXhZaVF6JbCVj3EZLQcO9iwmc9WWHbq 3E2vQ8Y6t5y4NyhSrxwFqMqtfTRcbhsU/GMbymhwLjQbMxjN39z7fGEsVZOM98OHl7jT NQwg== X-Gm-Message-State: AOAM532MnYzqx2AjoVEqfgbDvpEBX8sx1kmmqiyV/ZtWTiCjLWoci8r0 Vo0x2YDwxZwThhAvfh5dNBzasvU1QRs= X-Google-Smtp-Source: ABdhPJxaKvATvJcKM/p3sRrZdAYUBZaW3EkkpE4vAwzzsPiNpXHpRAotjVf4CnOg/RpQyF5KKuyVMg== X-Received: by 2002:a17:90b:2092:b0:1be:e373:2ed9 with SMTP id hb18-20020a17090b209200b001bee3732ed9mr3773083pjb.128.1646900529744; Thu, 10 Mar 2022 00:22:09 -0800 (PST) Received: from balhae.hsd1.ca.comcast.net ([2601:647:4800:3540:e7f1:5749:9be:64e1]) by smtp.gmail.com with ESMTPSA id a12-20020a056a000c8c00b004e1a76f0a8asm5903008pfv.51.2022.03.10.00.22.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 10 Mar 2022 00:22:09 -0800 (PST) Sender: Namhyung Kim From: Namhyung Kim To: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko Cc: Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , netdev@vger.kernel.org, bpf@vger.kernel.org, LKML , Arnaldo Carvalho de Melo , Peter Zijlstra , Eugene Loh , Hao Luo Subject: [PATCH 2/2] bpf/selftests: Test skipping stacktrace Date: Thu, 10 Mar 2022 00:22:02 -0800 Message-Id: <20220310082202.1229345-2-namhyung@kernel.org> X-Mailer: git-send-email 2.35.1.723.g4982287a31-goog In-Reply-To: <20220310082202.1229345-1-namhyung@kernel.org> References: <20220310082202.1229345-1-namhyung@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: bpf@iogearbox.net Add a test case for stacktrace with skip > 0 using a small sized buffer. It didn't support skipping entries greater than or equal to the size of buffer and filled the skipped part with 0. Signed-off-by: Namhyung Kim --- .../bpf/prog_tests/stacktrace_map_skip.c | 72 ++++++++++++++++ .../selftests/bpf/progs/stacktrace_map_skip.c | 82 +++++++++++++++++++ 2 files changed, 154 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/stacktrace_map_skip.c create mode 100644 tools/testing/selftests/bpf/progs/stacktrace_map_skip.c diff --git a/tools/testing/selftests/bpf/prog_tests/stacktrace_map_skip.c b/tools/testing/selftests/bpf/prog_tests/stacktrace_map_skip.c new file mode 100644 index 000000000000..bcb244aa3c78 --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/stacktrace_map_skip.c @@ -0,0 +1,72 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include "stacktrace_map_skip.skel.h" + +#define TEST_STACK_DEPTH 2 + +void test_stacktrace_map_skip(void) +{ + struct stacktrace_map_skip *skel; + int control_map_fd, stackid_hmap_fd, stackmap_fd, stack_amap_fd; + int err, stack_trace_len; + __u32 key, val, duration = 0; + + skel = stacktrace_map_skip__open_and_load(); + if (CHECK(!skel, "skel_open_and_load", "skeleton open failed\n")) + return; + + /* find map fds */ + control_map_fd = bpf_map__fd(skel->maps.control_map); + if (CHECK_FAIL(control_map_fd < 0)) + goto out; + + stackid_hmap_fd = bpf_map__fd(skel->maps.stackid_hmap); + if (CHECK_FAIL(stackid_hmap_fd < 0)) + goto out; + + stackmap_fd = bpf_map__fd(skel->maps.stackmap); + if (CHECK_FAIL(stackmap_fd < 0)) + goto out; + + stack_amap_fd = bpf_map__fd(skel->maps.stack_amap); + if (CHECK_FAIL(stack_amap_fd < 0)) + goto out; + + err = stacktrace_map_skip__attach(skel); + if (CHECK(err, "skel_attach", "skeleton attach failed\n")) + goto out; + + /* give some time for bpf program run */ + sleep(1); + + /* disable stack trace collection */ + key = 0; + val = 1; + bpf_map_update_elem(control_map_fd, &key, &val, 0); + + /* for every element in stackid_hmap, we can find a corresponding one + * in stackmap, and vise versa. + */ + err = compare_map_keys(stackid_hmap_fd, stackmap_fd); + if (CHECK(err, "compare_map_keys stackid_hmap vs. stackmap", + "err %d errno %d\n", err, errno)) + goto out; + + err = compare_map_keys(stackmap_fd, stackid_hmap_fd); + if (CHECK(err, "compare_map_keys stackmap vs. stackid_hmap", + "err %d errno %d\n", err, errno)) + goto out; + + stack_trace_len = TEST_STACK_DEPTH * sizeof(__u64); + err = compare_stack_ips(stackmap_fd, stack_amap_fd, stack_trace_len); + if (CHECK(err, "compare_stack_ips stackmap vs. stack_amap", + "err %d errno %d\n", err, errno)) + goto out; + + if (CHECK(skel->bss->failed, "check skip", + "failed to skip some depth: %d", skel->bss->failed)) + goto out; + +out: + stacktrace_map_skip__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/stacktrace_map_skip.c b/tools/testing/selftests/bpf/progs/stacktrace_map_skip.c new file mode 100644 index 000000000000..323248b17ae4 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/stacktrace_map_skip.c @@ -0,0 +1,82 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include + +#define TEST_STACK_DEPTH 2 + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __uint(max_entries, 1); + __type(key, __u32); + __type(value, __u32); +} control_map SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(max_entries, 16384); + __type(key, __u32); + __type(value, __u32); +} stackid_hmap SEC(".maps"); + +typedef __u64 stack_trace_t[TEST_STACK_DEPTH]; + +struct { + __uint(type, BPF_MAP_TYPE_STACK_TRACE); + __uint(max_entries, 16384); + __type(key, __u32); + __type(value, stack_trace_t); +} stackmap SEC(".maps"); + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY); + __uint(max_entries, 16384); + __type(key, __u32); + __type(value, stack_trace_t); +} stack_amap SEC(".maps"); + +/* taken from /sys/kernel/debug/tracing/events/sched/sched_switch/format */ +struct sched_switch_args { + unsigned long long pad; + char prev_comm[TASK_COMM_LEN]; + int prev_pid; + int prev_prio; + long long prev_state; + char next_comm[TASK_COMM_LEN]; + int next_pid; + int next_prio; +}; + +int failed = 0; + +SEC("tracepoint/sched/sched_switch") +int oncpu(struct sched_switch_args *ctx) +{ + __u32 max_len = TEST_STACK_DEPTH * sizeof(__u64); + __u32 key = 0, val = 0, *value_p; + __u64 *stack_p; + + value_p = bpf_map_lookup_elem(&control_map, &key); + if (value_p && *value_p) + return 0; /* skip if non-zero *value_p */ + + /* it should allow skipping whole buffer size entries */ + key = bpf_get_stackid(ctx, &stackmap, TEST_STACK_DEPTH); + if ((int)key >= 0) { + /* The size of stackmap and stack_amap should be the same */ + bpf_map_update_elem(&stackid_hmap, &key, &val, 0); + stack_p = bpf_map_lookup_elem(&stack_amap, &key); + if (stack_p) { + bpf_get_stack(ctx, stack_p, max_len, TEST_STACK_DEPTH); + /* it wrongly skipped all the entries and filled zero */ + if (stack_p[0] == 0) + failed = 1; + } + } else if ((int)key == -14/*EFAULT*/) { + /* old kernel doesn't support skipping that many entries */ + failed = 2; + } + + return 0; +} + +char _license[] SEC("license") = "GPL";