On 4/22/22 11:22 AM, Dmitrii Dolgov wrote:
Add a simple test for bpf link iterator
Signed-off-by: Dmitrii Dolgov <9erthalion6@xxxxxxxxx>
---
.../selftests/bpf/prog_tests/bpf_iter.c | 15 +++++++++++++++
.../selftests/bpf/progs/bpf_iter_bpf_link.c | 18 ++++++++++++++++++
2 files changed, 33 insertions(+)
create mode 100644 tools/testing/selftests/bpf/progs/bpf_iter_bpf_link.c
diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c
index 2c403ddc8076..e14a7a6d925c 100644
--- a/tools/testing/selftests/bpf/prog_tests/bpf_iter.c
+++ b/tools/testing/selftests/bpf/prog_tests/bpf_iter.c
@@ -26,6 +26,7 @@
#include "bpf_iter_bpf_sk_storage_map.skel.h"
#include "bpf_iter_test_kern5.skel.h"
#include "bpf_iter_test_kern6.skel.h"
+#include "bpf_iter_bpf_link.skel.h"
static int duration;
@@ -1172,6 +1173,20 @@ static void test_buf_neg_offset(void)
bpf_iter_test_kern6__destroy(skel);
}
+static void test_link_iter(void)
This function is used. Please add a proper subtest for this
in function test_bpf_iter().
+{
+ struct bpf_iter_bpf_link *skel;
+
+ skel = bpf_iter_bpf_link__open_and_load();
+ if (CHECK(skel, "bpf_iter_bpf_link__open_and_load",
+ "skeleton open_and_load unexpected success\n"))
+ return;
This is not correct. You should have CHECK(!skel, ...) to return
only if skel is NULL. The error message "skeleton open_and_load
unexpected success\n" is not correct either. Probably a copy-paste
error.
Also, since you are working on this file, probably convert all
CHECK's in this file to ASSERT_*() macros as patch #2. Then
this patch itself can be patch #3 using ASSERT_*() as well.
+
+ do_dummy_read(skel->progs.dump_bpf_link);
+
+ bpf_iter_bpf_link__destroy(skel);
+}
+
#define CMP_BUFFER_SIZE 1024
static char task_vma_output[CMP_BUFFER_SIZE];
static char proc_maps_output[CMP_BUFFER_SIZE];
diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_bpf_link.c b/tools/testing/selftests/bpf/progs/bpf_iter_bpf_link.c
new file mode 100644
index 000000000000..a5041fa1cda9
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/bpf_iter_bpf_link.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2020 Facebook */
copyright issue.
+#include "bpf_iter.h"
+#include <bpf/bpf_helpers.h>
+
+char _license[] SEC("license") = "GPL";
+
+SEC("iter/bpf_link")
+int dump_bpf_link(struct bpf_iter__bpf_link *ctx)
Please put bpf_iter__bpf_link definition in bpf_iter.h so
the test can work with an old version of vmlinux.h.
+{
+ struct seq_file *seq = ctx->meta->seq;
+ struct bpf_link *link = ctx->link;
+ int link_id;
The 'link' pointer could be NULL as in previous patch
we have:
+ .ctx_arg_info = {
+ { offsetof(struct bpf_iter__bpf_link, link),
+ PTR_TO_BTF_ID_OR_NULL },
+ },
So you need to add a check below.
if (!link)
return 0;
+
+ link_id = link->id;
+ bpf_seq_write(seq, &link_id, sizeof(link_id));
+ return 0;
+}