From 858e8b2eb4dd6fe6c4640463ad2f2ed3b8249ad4 Mon Sep 17 00:00:00 2001 From: Yonghong Song Date: Tue, 1 Sep 2020 19:31:13 -0700 Subject: [PATCH] selftests/bpf: Test task_file iterator without visiting pthreads Modified existing bpf_iter_test_file.c program to check whether all accessed files from the main thread or not. Modified existing bpf_iter_test_file program to check whether all accessed files from the main thread or not. $ ./test_progs -n 4 ... #4/7 task_file:OK ... #4 bpf_iter:OK Summary: 1/24 PASSED, 0 SKIPPED, 0 FAILED Signed-off-by: Yonghong Song Signed-off-by: Daniel Borkmann Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20200902023113.1672863-1-yhs@fb.com --- .../selftests/bpf/prog_tests/bpf_iter.c | 21 +++++++++++++++++++ .../selftests/bpf/progs/bpf_iter_task_file.c | 10 ++++++++- 2 files changed, 30 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c index 7375d9a6d2427..fe1a83b9875c6 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c @@ -132,17 +132,38 @@ static void test_task_stack(void) bpf_iter_task_stack__destroy(skel); } +static void *do_nothing(void *arg) +{ + pthread_exit(arg); +} + static void test_task_file(void) { struct bpf_iter_task_file *skel; + pthread_t thread_id; + void *ret; skel = bpf_iter_task_file__open_and_load(); if (CHECK(!skel, "bpf_iter_task_file__open_and_load", "skeleton open_and_load failed\n")) return; + skel->bss->tgid = getpid(); + + if (CHECK(pthread_create(&thread_id, NULL, &do_nothing, NULL), + "pthread_create", "pthread_create failed\n")) + goto done; + do_dummy_read(skel->progs.dump_task_file); + if (CHECK(pthread_join(thread_id, &ret) || ret != NULL, + "pthread_join", "pthread_join failed\n")) + goto done; + + CHECK(skel->bss->count != 0, "check_count", + "invalid non pthread file visit count %d\n", skel->bss->count); + +done: bpf_iter_task_file__destroy(skel); } diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_task_file.c b/tools/testing/selftests/bpf/progs/bpf_iter_task_file.c index 8b787baa26546..b2f7c7c5f9523 100644 --- a/tools/testing/selftests/bpf/progs/bpf_iter_task_file.c +++ b/tools/testing/selftests/bpf/progs/bpf_iter_task_file.c @@ -6,6 +6,9 @@ char _license[] SEC("license") = "GPL"; +int count = 0; +int tgid = 0; + SEC("iter/task_file") int dump_task_file(struct bpf_iter__task_file *ctx) { @@ -17,8 +20,13 @@ int dump_task_file(struct bpf_iter__task_file *ctx) if (task == (void *)0 || file == (void *)0) return 0; - if (ctx->meta->seq_num == 0) + if (ctx->meta->seq_num == 0) { + count = 0; BPF_SEQ_PRINTF(seq, " tgid gid fd file\n"); + } + + if (tgid == task->tgid && task->tgid != task->pid) + count++; BPF_SEQ_PRINTF(seq, "%8d %8d %8d %lx\n", task->tgid, task->pid, fd, (long)file->f_op); -- 2.39.5