In test_global_percpu_data.c, dump_percpu_data is defined after two
non-autoload SEC("?kprobe") programs (verifier_strncmp and
verifier_snprintf). If bpftool does not skip non-autoload programs when
generating light skeletons, dump_percpu_data.prog_fd is left invalid or
unpopulated.
Factor out a test_global_percpu_data_iter_fd() helper that operates
directly on prog/map file descriptors, and add an iter_lskel subtest to
verify that dump_percpu_data is properly loaded and executes correctly
when using the light skeleton.
Fixes: 4c9241bd731a ("selftests/bpf: Add tests to verify global percpu data")
Fixes: 1ed2294b31fc ("selftests/bpf: Test verifier log for global percpu data")
Signed-off-by: Thiébaud Weksteen <[email protected]>
---
v2 -> v3:
- Running the iter subtest against the lskel.
- Factor out test_global_percpu_data_iter_fd into a helper.
- Restore Fixes footers.
v1 -> v2:
- Accidentally dropped Fixes footers.
.../bpf/prog_tests/global_data_init.c | 92 ++++++++++++++-----
1 file changed, 69 insertions(+), 23 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/global_data_init.c
b/tools/testing/selftests/bpf/prog_tests/global_data_init.c
index 7c539cbcf3a1..797590127787 100644
--- a/tools/testing/selftests/bpf/prog_tests/global_data_init.c
+++ b/tools/testing/selftests/bpf/prog_tests/global_data_init.c
@@ -375,15 +375,43 @@ static void test_global_percpu_data_verifier_log(void)
RUN_TESTS(test_global_percpu_data);
}
-static void test_global_percpu_data_iter(void)
+static void test_global_percpu_data_iter_fd(int prog_fd, int map_fd, int
num_cpus,
+ bool *run_iter, __u32 *sum)
{
- DECLARE_LIBBPF_OPTS(bpf_iter_attach_opts, opts);
- struct test_global_percpu_data *skel;
+ DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts);
union bpf_iter_link_info linfo = {};
- struct bpf_link *link = NULL;
- int fd, num_cpus, len, err;
+ int link_fd, iter_fd, len;
char buf[16];
+ linfo.map.map_fd = map_fd;
+ opts.iter_info = &linfo;
+ opts.iter_info_len = sizeof(linfo);
+
+ link_fd = bpf_link_create(prog_fd, 0, BPF_TRACE_ITER, &opts);
+ if (!ASSERT_GE(link_fd, 0, "bpf_link_create"))
+ return;
+
+ iter_fd = bpf_iter_create(link_fd);
+ if (!ASSERT_GE(iter_fd, 0, "bpf_iter_create"))
+ goto out;
+
+ while ((len = read(iter_fd, buf, sizeof(buf))) > 0) {
+ /* no-op */
+ }
+ ASSERT_EQ(len, 0, "read iter");
+ ASSERT_TRUE(*run_iter, "run_iter");
+ ASSERT_EQ(*sum, 0xc0de * num_cpus, "sum");
+
+ close(iter_fd);
+out:
+ close(link_fd);
+}
+
+static void test_global_percpu_data_iter(void)
+{
+ struct test_global_percpu_data *skel;
+ int num_cpus, err;
+
num_cpus = libbpf_num_possible_cpus();
if (!ASSERT_GT(num_cpus, 0, "libbpf_num_possible_cpus"))
return;
@@ -395,34 +423,50 @@ static void test_global_percpu_data_iter(void)
skel->rodata->num_cpus = num_cpus;
skel->rodata->num_off = offsetof(struct test_global_percpu_data__percpu,
struct_data.nums[6]);
- skel->rodata->elem_sz = roundup(sizeof(struct
test_global_percpu_data__percpu), 8);
+ skel->rodata->elem_sz = roundup(sizeof(*skel->percpu), 8);
skel->percpu->struct_data.nums[6] = 0xc0de;
err = test_global_percpu_data__load(skel);
if (!ASSERT_OK(err, "test_global_percpu_data__load"))
goto out;
- linfo.map.map_fd = bpf_map__fd(skel->maps.percpu);
- opts.link_info = &linfo;
- opts.link_info_len = sizeof(linfo);
- link = bpf_program__attach_iter(skel->progs.dump_percpu_data, &opts);
- if (!ASSERT_OK_PTR(link, "bpf_program__attach_iter"))
- goto out;
+
test_global_percpu_data_iter_fd(bpf_program__fd(skel->progs.dump_percpu_data),
+ bpf_map__fd(skel->maps.percpu),
+ num_cpus, &skel->bss->run_iter,
+ &skel->bss->sum);
+out:
+ test_global_percpu_data__destroy(skel);
+}
- fd = bpf_iter_create(bpf_link__fd(link));
- if (!ASSERT_GE(fd, 0, "bpf_iter_create"))
- goto out;
+static void test_global_percpu_data_iter_lskel(void)
+{
+ struct test_global_percpu_data_lskel *skel;
+ int num_cpus, err;
- while ((len = read(fd, buf, sizeof(buf))) > 0)
- do { } while (0);
- ASSERT_EQ(len, 0, "read iter");
- ASSERT_TRUE(skel->bss->run_iter, "run_iter");
- ASSERT_EQ(skel->bss->sum, 0xc0de * num_cpus, "sum");
+ num_cpus = libbpf_num_possible_cpus();
+ if (!ASSERT_GT(num_cpus, 0, "libbpf_num_possible_cpus"))
+ return;
- close(fd);
+ skel = test_global_percpu_data_lskel__open();
+ if (!ASSERT_OK_PTR(skel, "test_global_percpu_data_lskel__open"))
+ return;
+
+ skel->rodata->num_cpus = num_cpus;
+ skel->rodata->num_off = offsetof(struct
test_global_percpu_data_lskel__percpu,
+ struct_data.nums[6]);
+ skel->rodata->elem_sz = roundup(sizeof(*skel->percpu), 8);
+ skel->percpu->struct_data.nums[6] = 0xc0de;
+
+ err = test_global_percpu_data_lskel__load(skel);
+ if (!ASSERT_OK(err, "test_global_percpu_data_lskel__load"))
+ goto out;
+
+ test_global_percpu_data_iter_fd(skel->progs.dump_percpu_data.prog_fd,
+ skel->maps.percpu.map_fd,
+ num_cpus, &skel->bss->run_iter,
+ &skel->bss->sum);
out:
- bpf_link__destroy(link);
- test_global_percpu_data__destroy(skel);
+ test_global_percpu_data_lskel__destroy(skel);
}
void test_global_percpu_data(void)
@@ -445,4 +489,6 @@ void test_global_percpu_data(void)
test_global_percpu_data_verifier_log();
if (test__start_subtest("iter"))
test_global_percpu_data_iter();
+ if (test__start_subtest("iter_lskel"))
+ test_global_percpu_data_iter_lskel();
}
--
2.55.0.1082.g2b9226bbc0-goog
