From 0a210af6d0a0595fef566e7eeb072f10f37774be Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Tue, 29 Mar 2022 18:15:02 -0700 Subject: [PATCH] bpf: selftests: Test fentry tracing a struct_ops program This patch tests attaching an fentry prog to a struct_ops prog. Signed-off-by: Martin KaFai Lau Signed-off-by: Alexei Starovoitov Acked-by: Yonghong Song Link: https://lore.kernel.org/bpf/20220330011502.2985292-1-kafai@fb.com --- .../selftests/bpf/prog_tests/dummy_st_ops.c | 23 +++++++++++++++++++ .../selftests/bpf/progs/trace_dummy_st_ops.c | 21 +++++++++++++++++ 2 files changed, 44 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/trace_dummy_st_ops.c diff --git a/tools/testing/selftests/bpf/prog_tests/dummy_st_ops.c b/tools/testing/selftests/bpf/prog_tests/dummy_st_ops.c index 5aa52cc31dc2e3..c11832657d2bb4 100644 --- a/tools/testing/selftests/bpf/prog_tests/dummy_st_ops.c +++ b/tools/testing/selftests/bpf/prog_tests/dummy_st_ops.c @@ -2,6 +2,7 @@ /* Copyright (C) 2021. Huawei Technologies Co., Ltd */ #include #include "dummy_st_ops.skel.h" +#include "trace_dummy_st_ops.skel.h" /* Need to keep consistent with definition in include/linux/bpf.h */ struct bpf_dummy_ops_state { @@ -56,6 +57,7 @@ static void test_dummy_init_ptr_arg(void) .ctx_in = args, .ctx_size_in = sizeof(args), ); + struct trace_dummy_st_ops *trace_skel; struct dummy_st_ops *skel; int fd, err; @@ -64,12 +66,33 @@ static void test_dummy_init_ptr_arg(void) return; fd = bpf_program__fd(skel->progs.test_1); + + trace_skel = trace_dummy_st_ops__open(); + if (!ASSERT_OK_PTR(trace_skel, "trace_dummy_st_ops__open")) + goto done; + + err = bpf_program__set_attach_target(trace_skel->progs.fentry_test_1, + fd, "test_1"); + if (!ASSERT_OK(err, "set_attach_target(fentry_test_1)")) + goto done; + + err = trace_dummy_st_ops__load(trace_skel); + if (!ASSERT_OK(err, "load(trace_skel)")) + goto done; + + err = trace_dummy_st_ops__attach(trace_skel); + if (!ASSERT_OK(err, "attach(trace_skel)")) + goto done; + err = bpf_prog_test_run_opts(fd, &attr); ASSERT_OK(err, "test_run"); ASSERT_EQ(in_state.val, 0x5a, "test_ptr_ret"); ASSERT_EQ(attr.retval, exp_retval, "test_ret"); + ASSERT_EQ(trace_skel->bss->val, exp_retval, "fentry_val"); +done: dummy_st_ops__destroy(skel); + trace_dummy_st_ops__destroy(trace_skel); } static void test_dummy_multiple_args(void) diff --git a/tools/testing/selftests/bpf/progs/trace_dummy_st_ops.c b/tools/testing/selftests/bpf/progs/trace_dummy_st_ops.c new file mode 100644 index 00000000000000..00a4be9d3074d7 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/trace_dummy_st_ops.c @@ -0,0 +1,21 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include + +int val = 0; + +SEC("fentry/test_1") +int BPF_PROG(fentry_test_1, __u64 *st_ops_ctx) +{ + __u64 state; + + /* Read the traced st_ops arg1 which is a pointer */ + bpf_probe_read_kernel(&state, sizeof(__u64), (void *)st_ops_ctx); + /* Read state->val */ + bpf_probe_read_kernel(&val, sizeof(__u32), (void *)state); + + return 0; +} + +char _license[] SEC("license") = "GPL";