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Tue, 06 Feb 2024 00:15:47 -0800 (PST) X-Forwarded-Encrypted: i=0; AJvYcCUF46L5VKx3mfnoMA9j94lBOUOjslGSAW+AGXZdSExLYZiQbqA6OJnQa6O/HghDsl7YvNMYUIiirofXhF1TOvorT3RCKY0jCB3h5zgJ1cWsTXiNF4KDCNpJF7IRPOlqaqjjuAwgPczUqWOpOkI68S0I2kRRSSy04uHgT0C08OYJ18NT4HNAdGjOUnszs0C5rYvAlr65r7btvySIFbZPe0PlttPibVUsFj2Ei+xI3BaEJ8mpvbA+HBd06uj8xiypSL3Hnnb3qxH2lYERJHQbPEuysGu6xkkGwulLGzqCUhQgDKTEoUicotDUT65Gty2JGzwb6YHhkHFli/sP5r0wO6CHhu9S9lu5YPOI0/ObdWAJYUwEXNCi8D1ggqfXWcogdei6vXx6uEtY1qqLmUbrR5aM8/epJVQSZ04c513f9e9GKkSpI+TIcA== Received: from localhost.localdomain ([39.144.105.129]) by smtp.gmail.com with ESMTPSA id 3-20020a630c43000000b005d7c02994c4sm1381660pgm.60.2024.02.06.00.15.35 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 06 Feb 2024 00:15:47 -0800 (PST) From: Yafang Shao To: ast@kernel.org, daniel@iogearbox.net, john.fastabend@gmail.com, andrii@kernel.org, martin.lau@linux.dev, eddyz87@gmail.com, song@kernel.org, yonghong.song@linux.dev, kpsingh@kernel.org, sdf@google.com, haoluo@google.com, jolsa@kernel.org, tj@kernel.org, void@manifault.com Cc: bpf@vger.kernel.org, Yafang Shao Subject: [PATCH v6 bpf-next 5/5] selftests/bpf: Add selftests for cpumask iter Date: Tue, 6 Feb 2024 16:14:16 +0800 Message-Id: <20240206081416.26242-6-laoar.shao@gmail.com> X-Mailer: git-send-email 2.30.1 (Apple Git-130) In-Reply-To: <20240206081416.26242-1-laoar.shao@gmail.com> References: <20240206081416.26242-1-laoar.shao@gmail.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 Add selftests for the newly added cpumask iter. - cpumask_iter_success - The number of CPUs should be expected when iterating over the cpumask - percpu data extracted from the percpu struct should be expected - It can work in both non-sleepable and sleepable prog - RCU lock is only required by bpf_iter_cpumask_new() - It is fine without calling bpf_iter_cpumask_next() - cpumask_iter_failure - RCU lock is required in sleepable prog - The cpumask to be iterated over can't be NULL - bpf_iter_cpumask_destroy() is required after calling bpf_iter_cpumask_new() - bpf_iter_cpumask_destroy() can only destroy an initialized iter - bpf_iter_cpumask_next() must use an initialized iter The result as follows, #64/37 cpumask/test_cpumask_iter:OK #64/38 cpumask/test_cpumask_iter_sleepable:OK #64/39 cpumask/test_cpumask_iter_sleepable:OK #64/40 cpumask/test_cpumask_iter_next_no_rcu:OK #64/41 cpumask/test_cpumask_iter_no_next:OK #64/42 cpumask/test_cpumask_iter:OK #64/43 cpumask/test_cpumask_iter_no_rcu:OK #64/44 cpumask/test_cpumask_iter_no_destroy:OK #64/45 cpumask/test_cpumask_iter_null_pointer:OK #64/46 cpumask/test_cpumask_iter_next_uninit:OK #64/47 cpumask/test_cpumask_iter_destroy_uninit:OK #64 cpumask:OK Signed-off-by: Yafang Shao --- tools/testing/selftests/bpf/config | 1 + .../selftests/bpf/prog_tests/cpumask.c | 152 ++++++++++++++++++ .../selftests/bpf/progs/cpumask_common.h | 3 + .../bpf/progs/cpumask_iter_failure.c | 99 ++++++++++++ .../bpf/progs/cpumask_iter_success.c | 126 +++++++++++++++ 5 files changed, 381 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/cpumask_iter_failure.c create mode 100644 tools/testing/selftests/bpf/progs/cpumask_iter_success.c diff --git a/tools/testing/selftests/bpf/config b/tools/testing/selftests/bpf/config index 01f241ea2c67..dd4b0935e35f 100644 --- a/tools/testing/selftests/bpf/config +++ b/tools/testing/selftests/bpf/config @@ -78,6 +78,7 @@ CONFIG_NF_CONNTRACK_MARK=y CONFIG_NF_DEFRAG_IPV4=y CONFIG_NF_DEFRAG_IPV6=y CONFIG_NF_NAT=y +CONFIG_PSI=y CONFIG_RC_CORE=y CONFIG_SECURITY=y CONFIG_SECURITYFS=y diff --git a/tools/testing/selftests/bpf/prog_tests/cpumask.c b/tools/testing/selftests/bpf/prog_tests/cpumask.c index ecf89df78109..78423745689c 100644 --- a/tools/testing/selftests/bpf/prog_tests/cpumask.c +++ b/tools/testing/selftests/bpf/prog_tests/cpumask.c @@ -1,9 +1,15 @@ // SPDX-License-Identifier: GPL-2.0 /* Copyright (c) 2023 Meta Platforms, Inc. and affiliates. */ +#define _GNU_SOURCE +#include + #include #include "cpumask_failure.skel.h" #include "cpumask_success.skel.h" +#include "cpumask_iter_success.skel.h" +#include "cpumask_iter_failure.skel.h" +#include "cgroup_helpers.h" static const char * const cpumask_success_testcases[] = { "test_alloc_free_cpumask", @@ -61,6 +67,142 @@ static void verify_success(const char *prog_name) cpumask_success__destroy(skel); } +static const char * const cpumask_iter_success_testcases[] = { + "test_cpumask_iter", + "test_cpumask_iter_sleepable", +}; + +static int read_percpu_data(struct bpf_link *link, int nr_cpu_exp, int nr_running_exp) +{ + int iter_fd, len, item, nr_running, psi_running, nr_cpus, err = -1; + char buf[128]; + size_t left; + char *p; + + iter_fd = bpf_iter_create(bpf_link__fd(link)); + if (!ASSERT_GE(iter_fd, 0, "iter_fd")) + return -1; + + memset(buf, 0, sizeof(buf)); + left = ARRAY_SIZE(buf); + p = buf; + while ((len = read(iter_fd, p, left)) > 0) { + p += len; + left -= len; + } + + item = sscanf(buf, "nr_running %u nr_cpus %u psi_running %u\n", + &nr_running, &nr_cpus, &psi_running); + if (!ASSERT_EQ(item, 3, "seq_format")) + goto out; + if (!ASSERT_EQ(nr_cpus, nr_cpu_exp, "nr_cpus")) + goto out; + if (!ASSERT_GE(nr_running, nr_running_exp, "nr_running")) + goto out; + if (!ASSERT_GE(psi_running, nr_running_exp, "psi_running")) + goto out; + + err = 0; +out: + close(iter_fd); + return err; +} + +static void verify_iter_success(const char *prog_name) +{ + DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts); + int cgrp_fd, nr_cpus, err, i, chosen = 0; + struct cpumask_iter_success *skel; + union bpf_iter_link_info linfo; + struct bpf_program *prog; + struct bpf_link *link; + cpu_set_t set; + + if (setup_cgroup_environment()) + return; + + /* Utilize the cgroup iter */ + cgrp_fd = get_root_cgroup(); + if (!ASSERT_GE(cgrp_fd, 0, "create_cgrp")) + goto cleanup; + + skel = cpumask_iter_success__open(); + if (!ASSERT_OK_PTR(skel, "cpumask_iter_success__open")) + goto close_fd; + + skel->bss->pid = getpid(); + nr_cpus = libbpf_num_possible_cpus(); + + err = cpumask_iter_success__load(skel); + if (!ASSERT_OK(err, "cpumask_iter_success__load")) + goto destroy; + + prog = bpf_object__find_program_by_name(skel->obj, prog_name); + if (!ASSERT_OK_PTR(prog, "bpf_object__find_program_by_name")) + goto destroy; + + memset(&linfo, 0, sizeof(linfo)); + linfo.cgroup.cgroup_fd = cgrp_fd; + linfo.cgroup.order = BPF_CGROUP_ITER_SELF_ONLY; + opts.link_info = &linfo; + opts.link_info_len = sizeof(linfo); + link = bpf_program__attach_iter(prog, &opts); + if (!ASSERT_OK_PTR(link, "bpf_program__attach")) + goto destroy; + + /* Case 1): Enable all possible CPUs */ + CPU_ZERO(&set); + for (i = 0; i < nr_cpus; i++) + CPU_SET(i, &set); + err = sched_setaffinity(skel->bss->pid, sizeof(set), &set); + if (!ASSERT_OK(err, "setaffinity_all_cpus")) + goto free_link; + err = read_percpu_data(link, nr_cpus, 1); + if (!ASSERT_OK(err, "read_percpu_data")) + goto free_link; + if (!ASSERT_OK(skel->bss->err, "null_rq")) + goto free_link; + + /* Case 2): CPU0 only */ + CPU_ZERO(&set); + CPU_SET(0, &set); + err = sched_setaffinity(skel->bss->pid, sizeof(set), &set); + if (!ASSERT_OK(err, "setaffinity_cpu0")) + goto free_link; + err = read_percpu_data(link, 1, 1); + if (!ASSERT_OK(err, "read_percpu_data")) + goto free_link; + if (!ASSERT_OK(skel->bss->err, "null_rq_psi")) + goto free_link; + + /* Case 3): Partial CPUs */ + CPU_ZERO(&set); + for (i = 0; i < nr_cpus; i++) { + if (i < 4 && i & 0x1) + continue; + if (i > 8 && i & 0x2) + continue; + CPU_SET(i, &set); + chosen++; + } + err = sched_setaffinity(skel->bss->pid, sizeof(set), &set); + if (!ASSERT_OK(err, "setaffinity_partial_cpus")) + goto free_link; + err = read_percpu_data(link, chosen, 1); + if (!ASSERT_OK(err, "read_percpu_data")) + goto free_link; + ASSERT_OK(skel->bss->err, "null_rq_psi"); + +free_link: + bpf_link__destroy(link); +destroy: + cpumask_iter_success__destroy(skel); +close_fd: + close(cgrp_fd); +cleanup: + cleanup_cgroup_environment(); +} + void test_cpumask(void) { int i; @@ -74,4 +216,14 @@ void test_cpumask(void) RUN_TESTS(cpumask_success); RUN_TESTS(cpumask_failure); + + for (i = 0; i < ARRAY_SIZE(cpumask_iter_success_testcases); i++) { + if (!test__start_subtest(cpumask_iter_success_testcases[i])) + continue; + + verify_iter_success(cpumask_iter_success_testcases[i]); + } + + RUN_TESTS(cpumask_iter_success); + RUN_TESTS(cpumask_iter_failure); } diff --git a/tools/testing/selftests/bpf/progs/cpumask_common.h b/tools/testing/selftests/bpf/progs/cpumask_common.h index c705d8112a35..fb65943ef130 100644 --- a/tools/testing/selftests/bpf/progs/cpumask_common.h +++ b/tools/testing/selftests/bpf/progs/cpumask_common.h @@ -56,6 +56,9 @@ u32 bpf_cpumask_any_distribute(const struct cpumask *src) __ksym __weak; u32 bpf_cpumask_any_and_distribute(const struct cpumask *src1, const struct cpumask *src2) __ksym __weak; u32 bpf_cpumask_weight(const struct cpumask *cpumask) __ksym __weak; +int bpf_iter_cpumask_new(struct bpf_iter_cpumask *it, const struct cpumask *mask) __ksym __weak; +int *bpf_iter_cpumask_next(struct bpf_iter_cpumask *it) __ksym __weak; +void bpf_iter_cpumask_destroy(struct bpf_iter_cpumask *it) __ksym __weak; void bpf_rcu_read_lock(void) __ksym __weak; void bpf_rcu_read_unlock(void) __ksym __weak; diff --git a/tools/testing/selftests/bpf/progs/cpumask_iter_failure.c b/tools/testing/selftests/bpf/progs/cpumask_iter_failure.c new file mode 100644 index 000000000000..3d304cee0a72 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/cpumask_iter_failure.c @@ -0,0 +1,99 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2024 Yafang Shao */ + +#include "vmlinux.h" +#include +#include + +#include "bpf_misc.h" +#include "task_kfunc_common.h" +#include "cpumask_common.h" + +char _license[] SEC("license") = "GPL"; + +SEC("iter.s/cgroup") +__failure __msg("R2 must be a rcu pointer") +int BPF_PROG(test_cpumask_iter_no_rcu, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct task_struct *p; + int *cpu; + + p = bpf_task_from_pid(1); + if (!p) + return 1; + + bpf_for_each(cpumask, cpu, p->cpus_ptr) { + } + bpf_task_release(p); + return 0; +} + +SEC("iter/cgroup") +__failure __msg("Possibly NULL pointer passed to trusted arg1") +int BPF_PROG(test_cpumask_iter_null_pointer, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct cpumask *mask = NULL; + int *cpu; + + bpf_for_each(cpumask, cpu, mask) { + } + return 0; +} + +SEC("iter.s/cgroup") +__failure __msg("Unreleased reference id=3 alloc_insn=10") +int BPF_PROG(test_cpumask_iter_no_destroy, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct bpf_iter_cpumask it; + struct task_struct *p; + + p = bpf_task_from_pid(1); + if (!p) + return 1; + + bpf_rcu_read_lock(); + bpf_iter_cpumask_new(&it, p->cpus_ptr); + bpf_rcu_read_unlock(); + + bpf_iter_cpumask_next(&it); + bpf_task_release(p); + return 0; +} + +SEC("iter/cgroup") +__failure __msg("expected an initialized iter_cpumask as arg #1") +int BPF_PROG(test_cpumask_iter_next_uninit, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct bpf_iter_cpumask *it = NULL; + + bpf_iter_cpumask_next(it); + return 0; +} + +SEC("iter/cgroup") +__failure __msg("expected an initialized iter_cpumask as arg #1") +int BPF_PROG(test_cpumask_iter_next_uninit2, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct bpf_iter_cpumask it = {}; + + bpf_iter_cpumask_next(&it); + return 0; +} + +SEC("iter/cgroup") +__failure __msg("expected an initialized iter_cpumask as arg #1") +int BPF_PROG(test_cpumask_iter_destroy_uninit, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct bpf_iter_cpumask_kern it = {.cpu = -1}; + struct bpf_cpumask *mask; + + mask = bpf_cpumask_create(); + if (!mask) + return 1; + + bpf_cpumask_setall(mask); + it.mask = &mask->cpumask; + bpf_iter_cpumask_destroy((struct bpf_iter_cpumask *)&it); + bpf_cpumask_release(mask); + return 0; +} diff --git a/tools/testing/selftests/bpf/progs/cpumask_iter_success.c b/tools/testing/selftests/bpf/progs/cpumask_iter_success.c new file mode 100644 index 000000000000..a71db42cc38a --- /dev/null +++ b/tools/testing/selftests/bpf/progs/cpumask_iter_success.c @@ -0,0 +1,126 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* Copyright (c) 2024 Yafang Shao */ + +#include "vmlinux.h" +#include +#include + +#include "task_kfunc_common.h" +#include "cpumask_common.h" + +char _license[] SEC("license") = "GPL"; + +extern const struct psi_group_cpu system_group_pcpu __ksym __weak; +extern const struct rq runqueues __ksym __weak; + +int pid; + +static void read_percpu_data(struct bpf_iter_meta *meta, struct cgroup *cgrp, const cpumask_t *mask) +{ + u32 nr_running = 0, psi_nr_running = 0, nr_cpus = 0; + struct psi_group_cpu *groupc; + struct rq *rq; + int *cpu; + + bpf_for_each(cpumask, cpu, mask) { + rq = (struct rq *)bpf_per_cpu_ptr(&runqueues, *cpu); + if (!rq) { + err += 1; + continue; + } + nr_running += rq->nr_running; + nr_cpus += 1; + + groupc = (struct psi_group_cpu *)bpf_per_cpu_ptr(&system_group_pcpu, *cpu); + if (!groupc) { + err += 1; + continue; + } + psi_nr_running += groupc->tasks[NR_RUNNING]; + } + BPF_SEQ_PRINTF(meta->seq, "nr_running %u nr_cpus %u psi_running %u\n", + nr_running, nr_cpus, psi_nr_running); +} + +SEC("iter.s/cgroup") +int BPF_PROG(test_cpumask_iter_sleepable, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct task_struct *p; + + /* epilogue */ + if (!cgrp) + return 0; + + bpf_rcu_read_lock(); + p = bpf_task_from_pid(pid); + if (!p) { + bpf_rcu_read_unlock(); + return 1; + } + + read_percpu_data(meta, cgrp, p->cpus_ptr); + bpf_task_release(p); + bpf_rcu_read_unlock(); + return 0; +} + +SEC("iter/cgroup") +int BPF_PROG(test_cpumask_iter, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct task_struct *p; + + /* epilogue */ + if (!cgrp) + return 0; + + p = bpf_task_from_pid(pid); + if (!p) + return 1; + + read_percpu_data(meta, cgrp, p->cpus_ptr); + bpf_task_release(p); + return 0; +} + +SEC("iter.s/cgroup") +int BPF_PROG(test_cpumask_iter_next_no_rcu, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct bpf_iter_cpumask it; + struct task_struct *p; + + p = bpf_task_from_pid(1); + if (!p) + return 1; + + /* RCU is only required by bpf_iter_cpumask_new(). */ + bpf_rcu_read_lock(); + bpf_iter_cpumask_new(&it, p->cpus_ptr); + bpf_rcu_read_unlock(); + + bpf_iter_cpumask_next(&it); + bpf_iter_cpumask_destroy(&it); + + bpf_task_release(p); + return 0; +} + +SEC("iter.s/cgroup") +int BPF_PROG(test_cpumask_iter_no_next, struct bpf_iter_meta *meta, struct cgroup *cgrp) +{ + struct bpf_iter_cpumask it; + struct task_struct *p; + + p = bpf_task_from_pid(1); + if (!p) + return 1; + + bpf_rcu_read_lock(); + bpf_iter_cpumask_new(&it, p->cpus_ptr); + bpf_rcu_read_unlock(); + + /* It is fine without calling bpf_iter_cpumask_next(). */ + + bpf_iter_cpumask_destroy(&it); + bpf_task_release(p); + return 0; +}