From patchwork Sun Oct 22 15:45:27 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuyi Zhou X-Patchwork-Id: 13431878 X-Patchwork-Delegate: bpf@iogearbox.net Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5AFD1107A4 for ; Sun, 22 Oct 2023 15:45:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bytedance.com header.i=@bytedance.com header.b="KUoMLtYJ" Received: from mail-pf1-x436.google.com (mail-pf1-x436.google.com [IPv6:2607:f8b0:4864:20::436]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CFBC1F4 for ; Sun, 22 Oct 2023 08:45:43 -0700 (PDT) Received: by mail-pf1-x436.google.com with SMTP id d2e1a72fcca58-6b5af4662b7so1938036b3a.3 for ; Sun, 22 Oct 2023 08:45:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance.com; s=google; t=1697989543; x=1698594343; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=vaiHO7SBSXsd0QCikkafn6mecL9krZTUGDMsMzgZbU4=; b=KUoMLtYJBWNkrrVLl+plSUHrq1Fg+FsIPl7ptEVl+ZmN7S4o0y8XuRvFXl7yUlAhCr MKG1giiHv5N2Qi//y5MI+45b2TYKTVtR6mQRjgOMuXBssnbIuybkvgKfN3bld0zZEfSk b8AjE36CIKas9UsdKt/h/JIocxjjp5EN/4U7nJ32Qo9P7s0q40QmsFFfJA7dL8bb6zPt jef/uNQa7uclgbU0aUqw5M1MCzXlg+as48xZS9wJH0t5lhSVC5ymFXjV2Jb6utEa7ZJg Rq6coRBdTMwYXHOR2ispcSAQO9PGt8GaxylZemNRhcHK8pEukNhQl43jGLmWPBAv/keq 5x6w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697989543; x=1698594343; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=vaiHO7SBSXsd0QCikkafn6mecL9krZTUGDMsMzgZbU4=; b=LS9sROb/sRFKZt4LDeDjz4Btl1GPyz+54EQ8DcpLJ4mWTdHrDjvJWFzJsyV50KIrSY moYW0BeUrsTy8yTaFl5rcPshAo7YEpsNoeFk8yUfIwKWODXBZp0K1TBbMYB5ZbpaC2DT eL3P2qtcWQ+4ASlxT/g2wC7+kSCTivneISuxbQfsKmuz8u9GnrOYzSwOpuQRJQ78xlBw tvgRFNcKA5TzLYmXFg/DpaZDWyNFmwafej+KtU2/GnznL0BQttts1y6aNAzFCxRZTVlv cBcgU6h4P3sWatqHzNrnXKZxzKgF9WdU2yNOrmCSUpm+gBUADzLN3/9WFDDnlOa4Btck cG2w== X-Gm-Message-State: AOJu0Ywv5V/l+KM2gb7yXdUy0XFXtsj1C6ptuZCzNGWpGBhsRk0wpSG/ o6fJZbu7NtPVcem2Jyfl+9o+kV+xjUQPzApfQyE3ew== X-Google-Smtp-Source: AGHT+IFrzhHTXSfJpZpO4bd3xmL0DHpuCTad9SyeO3RAV7nuOssFJCsOh/MPLmRTHp8r2I2HDjrXGg== X-Received: by 2002:a05:6a21:6d94:b0:171:e3b2:7d52 with SMTP id wl20-20020a056a216d9400b00171e3b27d52mr4892588pzb.59.1697989543143; Sun, 22 Oct 2023 08:45:43 -0700 (PDT) Received: from n37-019-243.byted.org ([180.184.49.4]) by smtp.gmail.com with ESMTPSA id l2-20020a170902d34200b001bbdd44bbb6sm4551996plk.136.2023.10.22.08.45.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 22 Oct 2023 08:45:42 -0700 (PDT) From: Chuyi Zhou To: bpf@vger.kernel.org Cc: ast@kernel.org, daniel@iogearbox.net, andrii@kernel.org, martin.lau@kernel.org, Chuyi Zhou Subject: [PATCH bpf-next 2/2] selftests/bpf: Add test for css_task iter combining with cgroup iter Date: Sun, 22 Oct 2023 23:45:27 +0800 Message-Id: <20231022154527.229117-3-zhouchuyi@bytedance.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20231022154527.229117-1-zhouchuyi@bytedance.com> References: <20231022154527.229117-1-zhouchuyi@bytedance.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: bpf@iogearbox.net This patch adds a test which demonstrates how css_task iter can be combined with cgroup iter and it won't cause deadlock, though cgroup iter is not sleepable. Signed-off-by: Chuyi Zhou --- .../selftests/bpf/prog_tests/cgroup_iter.c | 33 +++++++++++++++ .../selftests/bpf/progs/iters_css_task.c | 41 +++++++++++++++++++ 2 files changed, 74 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/cgroup_iter.c b/tools/testing/selftests/bpf/prog_tests/cgroup_iter.c index e02feb5fae97..3679687a6927 100644 --- a/tools/testing/selftests/bpf/prog_tests/cgroup_iter.c +++ b/tools/testing/selftests/bpf/prog_tests/cgroup_iter.c @@ -4,6 +4,7 @@ #include #include #include +#include "iters_css_task.skel.h" #include "cgroup_iter.skel.h" #include "cgroup_helpers.h" @@ -263,6 +264,35 @@ static void test_walk_dead_self_only(struct cgroup_iter *skel) close(cgrp_fd); } +static void test_walk_self_only_css_task(void) +{ + struct iters_css_task *skel = NULL; + int err; + + skel = iters_css_task__open(); + if (!ASSERT_OK_PTR(skel, "skel_open")) + return; + + bpf_program__set_autoload(skel->progs.cgroup_id_printer, true); + + err = iters_css_task__load(skel); + if (!ASSERT_OK(err, "skel_load")) + goto cleanup; + + err = join_cgroup(cg_path[CHILD2]); + if (!ASSERT_OK(err, "join_cgroup")) + goto cleanup; + + skel->bss->target_pid = getpid(); + snprintf(expected_output, sizeof(expected_output), + PROLOGUE "%8llu\n" EPILOGUE, cg_id[CHILD2]); + read_from_cgroup_iter(skel->progs.cgroup_id_printer, cg_fd[CHILD2], + BPF_CGROUP_ITER_SELF_ONLY, "test_walk_self_only_css_task"); + ASSERT_EQ(skel->bss->css_task_cnt, 1, "css_task_cnt"); +cleanup: + iters_css_task__destroy(skel); +} + void test_cgroup_iter(void) { struct cgroup_iter *skel = NULL; @@ -293,6 +323,9 @@ void test_cgroup_iter(void) test_walk_self_only(skel); if (test__start_subtest("cgroup_iter__dead_self_only")) test_walk_dead_self_only(skel); + if (test__start_subtest("cgroup_iter__self_only_css_task")) + test_walk_self_only_css_task(); + out: cgroup_iter__destroy(skel); cleanup_cgroups(); diff --git a/tools/testing/selftests/bpf/progs/iters_css_task.c b/tools/testing/selftests/bpf/progs/iters_css_task.c index 5089ce384a1c..0974e6f44328 100644 --- a/tools/testing/selftests/bpf/progs/iters_css_task.c +++ b/tools/testing/selftests/bpf/progs/iters_css_task.c @@ -10,6 +10,7 @@ char _license[] SEC("license") = "GPL"; +struct cgroup *bpf_cgroup_acquire(struct cgroup *p) __ksym; struct cgroup *bpf_cgroup_from_id(u64 cgid) __ksym; void bpf_cgroup_release(struct cgroup *p) __ksym; @@ -45,3 +46,43 @@ int BPF_PROG(iter_css_task_for_each, struct vm_area_struct *vma, return -EPERM; } + +static inline u64 cgroup_id(struct cgroup *cgrp) +{ + return cgrp->kn->id; +} + +SEC("?iter/cgroup") +int cgroup_id_printer(struct bpf_iter__cgroup *ctx) +{ + struct seq_file *seq = ctx->meta->seq; + struct cgroup *cgrp, *acquired; + struct cgroup_subsys_state *css; + struct task_struct *task; + + cgrp = ctx->cgroup; + + /* epilogue */ + if (cgrp == NULL) { + BPF_SEQ_PRINTF(seq, "epilogue\n"); + return 0; + } + + /* prologue */ + if (ctx->meta->seq_num == 0) + BPF_SEQ_PRINTF(seq, "prologue\n"); + + BPF_SEQ_PRINTF(seq, "%8llu\n", cgroup_id(cgrp)); + + acquired = bpf_cgroup_from_id(cgroup_id(cgrp)); + if (!acquired) + return 0; + css = &acquired->self; + css_task_cnt = 0; + bpf_for_each(css_task, task, css, CSS_TASK_ITER_PROCS) { + if (task->pid == target_pid) + css_task_cnt++; + } + bpf_cgroup_release(acquired); + return 0; +}