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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 12327C7EE21 for ; Fri, 5 May 2023 03:21:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229535AbjEEDVw (ORCPT ); Thu, 4 May 2023 23:21:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49992 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229871AbjEEDVe (ORCPT ); Thu, 4 May 2023 23:21:34 -0400 Received: from mail-pg1-x536.google.com (mail-pg1-x536.google.com [IPv6:2607:f8b0:4864:20::536]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 04B7912084 for ; Thu, 4 May 2023 20:21:04 -0700 (PDT) Received: by mail-pg1-x536.google.com with SMTP id 41be03b00d2f7-51b4ef5378bso1096790a12.1 for ; Thu, 04 May 2023 20:21:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1683256863; x=1685848863; h=content-transfer-encoding:in-reply-to:from:references:cc:to:subject :user-agent:mime-version:date:message-id:from:to:cc:subject:date :message-id:reply-to; bh=UuHz1ga8iYYT3T2UezfJAayUdEePBZ0K98E4KKO6lr0=; b=WLRPobWtNTXI+Tq/qWsGl3AfIvzw0jmzVCLXthehEsHmTI990BjAbZ9iCCLyObfjI1 oLwWzYNMYBc2zhoB4qwDLsdtlj6wIDRjy0d6WyZP1nBTu+wCkR5V/lsgWqTGVSQ8hvc2 jnmJvNOv3q32Pg2z6rGHKdCX16GWWVfi2TwVXvYwF27/reE+WXmNxUuWARoNmjVWkt5j 3UciFHGxA1JAzJMtM4SYOnjjdlCHYndxNbgn9JXiC7/ANbM7J3iEOabxdnandZO7QurW P7xqFUM77vCnMdxGcHoDav5F5ui8pIiHjDl+6qJqRj+qOi7NxwDdcwAar7OfxwP7prnS zNcg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683256863; x=1685848863; h=content-transfer-encoding:in-reply-to:from:references:cc:to:subject :user-agent:mime-version:date:message-id:x-gm-message-state:from:to :cc:subject:date:message-id:reply-to; bh=UuHz1ga8iYYT3T2UezfJAayUdEePBZ0K98E4KKO6lr0=; b=jn4X4O+ntuIqlCBt5sec36tMF4zlKvHIEIYzYvUUZfNEh/mAA6nHGoNyaZKPXcK2eH 4EC9Gv+QVKV83mFmUOAuiKJHSb9SFE7dj33bIPL+zZ2NgPOrsS1GMvDs2tLBu6rBLy4t 2uqi+0NY39+HARbXrYHDlIIXTXeBWGP+OcIs6rD5f6JI6PqzrwBgu0uGIsI2cyR43bW2 BvD1ujgM0sEEx/fVmML1Y9/J59YNIBAr8FU5Z68rWR1FqX3gpjUAyh2waIEmcBk/LebR 35ksbJF5bVSzzDoeVbTLktARdzJeNz/0m5QGhW1gKkNvsBDCLIUGRPLvPimBDLsqYwoR 2KBA== X-Gm-Message-State: AC+VfDwwfceQI+7vKQFz0t2NLEfnrd7aHVxm+bVcKh7fwKbCs5UuowKC xgxVa855ZTj7DXyKTe+Cs2Y8eg== X-Google-Smtp-Source: ACHHUZ6HpiO6PuX63DKsP4o4xrLtKGOT4wwh6m+jy09qIntVA+v7OufF9xrMtLzZW1J5J/VMLzXZPg== X-Received: by 2002:a17:902:ea07:b0:1a9:a408:a502 with SMTP id s7-20020a170902ea0700b001a9a408a502mr62192plg.1.1683256863462; Thu, 04 May 2023 20:21:03 -0700 (PDT) Received: from [10.71.57.173] ([139.177.225.254]) by smtp.gmail.com with ESMTPSA id w1-20020a170902d70100b001a072aedec7sm399064ply.75.2023.05.04.20.20.56 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 04 May 2023 20:21:03 -0700 (PDT) Message-ID: Date: Fri, 5 May 2023 11:20:54 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.13.1 Subject: Re: Re: [PATCH bpf-next v5 2/2] selftests/bpf: Add testcase for bpf_task_under_cgroup To: Yonghong Song , martin.lau@linux.dev, ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, song@kernel.org, yhs@fb.com, john.fastabend@gmail.com, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org, davem@davemloft.net, edumazet@google.com, kuba@kernel.org, pabeni@redhat.com, mykolal@fb.com, shuah@kernel.org Cc: bpf@vger.kernel.org, linux-kernel@vger.kernel.org, netdev@vger.kernel.org, linux-kselftest@vger.kernel.org, yangzhenze@bytedance.com, wangdongdong.6@bytedance.com References: <20230504031513.13749-1-zhoufeng.zf@bytedance.com> <20230504031513.13749-3-zhoufeng.zf@bytedance.com> <63138022-e28f-a63c-6f4c-61b61e585641@meta.com> From: Feng Zhou In-Reply-To: <63138022-e28f-a63c-6f4c-61b61e585641@meta.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 在 2023/5/4 22:46, Yonghong Song 写道: > > > On 5/3/23 8:15 PM, Feng zhou wrote: >> From: Feng Zhou >> >> test_progs: >> Tests new kfunc bpf_task_under_cgroup(). >> >> The bpf program saves the new task's pid within a given cgroup to >> the remote_pid, which is convenient for the user-mode program to >> verify the test correctness. >> >> The user-mode program creates its own mount namespace, and mounts the >> cgroupsv2 hierarchy in there, call the fork syscall, then check if >> remote_pid and local_pid are unequal. >> >> Signed-off-by: Feng Zhou > > Ack with a few nits below. You can carry my Ack in the > next revision. > > Acked-by: Yonghong Song > > Will do >> --- >>   tools/testing/selftests/bpf/DENYLIST.s390x    |  1 + >>   .../bpf/prog_tests/task_under_cgroup.c        | 54 +++++++++++++++++++ >>   .../bpf/progs/test_task_under_cgroup.c        | 51 ++++++++++++++++++ >>   3 files changed, 106 insertions(+) >>   create mode 100644 >> tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c >>   create mode 100644 >> tools/testing/selftests/bpf/progs/test_task_under_cgroup.c >> >> diff --git a/tools/testing/selftests/bpf/DENYLIST.s390x >> b/tools/testing/selftests/bpf/DENYLIST.s390x >> index c7463f3ec3c0..5061d9e24c16 100644 >> --- a/tools/testing/selftests/bpf/DENYLIST.s390x >> +++ b/tools/testing/selftests/bpf/DENYLIST.s390x >> @@ -26,3 +26,4 @@ user_ringbuf                             # failed to >> find kernel BTF type ID of >>   verif_stats                              # >> trace_vprintk__open_and_load unexpected error: >> -9                           (?) >>   xdp_bonding                              # failed to auto-attach >> program 'trace_on_entry': -524                        (trampoline) >>   xdp_metadata                             # JIT does not support >> calling kernel function                                (kfunc) >> +test_task_under_cgroup                   # JIT does not support >> calling kernel function                                (kfunc) >> diff --git >> a/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c >> b/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c >> new file mode 100644 >> index 000000000000..fa3a98eae5ef >> --- /dev/null >> +++ b/tools/testing/selftests/bpf/prog_tests/task_under_cgroup.c >> @@ -0,0 +1,54 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* Copyright (c) 2023 Bytedance */ >> + >> +#include >> +#include >> +#include >> +#include "test_task_under_cgroup.skel.h" >> + >> +#define FOO    "/foo" >> + >> +void test_task_under_cgroup(void) >> +{ >> +    struct test_task_under_cgroup *skel; >> +    int ret, foo = -1; > > You do not need to initialize 'foo' here. > >> +    pid_t pid; >> + >> +    foo = test__join_cgroup(FOO); >> +    if (!ASSERT_OK(foo < 0, "cgroup_join_foo")) >> +        return; >> + >> +    skel = test_task_under_cgroup__open(); >> +    if (!ASSERT_OK_PTR(skel, "test_task_under_cgroup__open")) >> +        goto cleanup; >> + >> +    skel->rodata->local_pid = getpid(); >> +    skel->bss->remote_pid = getpid(); >> +    skel->rodata->cgid = get_cgroup_id(FOO); >> + >> +    ret = test_task_under_cgroup__load(skel); >> +    if (!ASSERT_OK(ret, "test_task_under_cgroup__load")) >> +        goto cleanup; >> + >> +    ret = test_task_under_cgroup__attach(skel); >> +    if (!ASSERT_OK(ret, "test_task_under_cgroup__attach")) >> +        goto cleanup; >> + >> +    pid = fork(); >> +    if (pid == 0) >> +        exit(0); >> + >> +    ret = (pid == -1); >> +    if (ASSERT_OK(ret, "fork process")) >> +        wait(NULL); >> + >> +    test_task_under_cgroup__detach(skel); >> + >> +    ASSERT_NEQ(skel->bss->remote_pid, skel->rodata->local_pid, >> +           "test task_under_cgroup"); >> + >> +cleanup: >> +    close(foo); >> + >> +    test_task_under_cgroup__destroy(skel); > > Let us just do: > cleanup: >     test_task_under_cgroup__destroy(skel); >     close(foo); > > This is the reverse order of test__join_cgroup() and > test_task_under_cgroup__open(). > >> +} >> diff --git >> a/tools/testing/selftests/bpf/progs/test_task_under_cgroup.c >> b/tools/testing/selftests/bpf/progs/test_task_under_cgroup.c >> new file mode 100644 >> index 000000000000..79d98e65c7eb >> --- /dev/null >> +++ b/tools/testing/selftests/bpf/progs/test_task_under_cgroup.c >> @@ -0,0 +1,51 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* Copyright (c) 2023 Bytedance */ >> + >> +#include >> +#include >> +#include >> + >> +#include "bpf_misc.h" >> + >> +struct cgroup *bpf_cgroup_from_id(u64 cgid) __ksym; >> +long bpf_task_under_cgroup(struct task_struct *task, struct cgroup >> *ancestor) __ksym; >> +void bpf_cgroup_release(struct cgroup *p) __ksym; >> +struct task_struct *bpf_task_acquire(struct task_struct *p) __ksym; >> +void bpf_task_release(struct task_struct *p) __ksym; >> + >> +const volatile int local_pid; >> +const volatile __u64 cgid; >> +int remote_pid; >> + >> +SEC("tp_btf/task_newtask") >> +int BPF_PROG(handle__task_newtask, struct task_struct *task, u64 >> clone_flags) >> +{ >> +    struct cgroup *cgrp = NULL; >> +    struct task_struct *acquired; >> + >> +    if (local_pid != (bpf_get_current_pid_tgid() >> 32)) >> +        return 0; >> + >> +    acquired = bpf_task_acquire(task); >> +    if (!acquired) >> +        return 0; >> + >> +    if (local_pid == acquired->tgid) >> +        goto out; >> + >> +    cgrp = bpf_cgroup_from_id(cgid); >> +    if (!cgrp) >> +        goto out; >> + >> +    if (bpf_task_under_cgroup(acquired, cgrp)) >> +        remote_pid = acquired->tgid; >> + >> +out: >> +    if (acquired) >> +        bpf_task_release(acquired); >> +    if (cgrp) >> +        bpf_cgroup_release(cgrp); > > Let us do: > out: >     if (cgrp) >         bpf_cgroup_release(cgrp); >     bpf_task_release(acquired); > >> +    return 0; >> +} >> + >> +char _license[] SEC("license") = "GPL";