Extend test_bpftool.py with following test cases:
- Load a small program that has some context types in it's BTF,
verify that "bpftool btf dump file ... format c" emits
preserve_static_offset attribute.
- Load a small program that has no context types in it's BTF,
verify that "bpftool btf dump file ... format c" does not emit
preserve_static_offset attribute.
Signed-off-by: Eduard Zingerman <eddyz87@xxxxxxxxx>
---
.../bpf/progs/dummy_no_context_btf.c | 12 ++++
.../selftests/bpf/progs/dummy_sk_buff_user.c | 14 +++++
tools/testing/selftests/bpf/test_bpftool.py | 61 +++++++++++++++++++
3 files changed, 87 insertions(+)
create mode 100644 tools/testing/selftests/bpf/progs/dummy_no_context_btf.c
create mode 100644 tools/testing/selftests/bpf/progs/dummy_sk_buff_user.c
diff --git a/tools/testing/selftests/bpf/progs/dummy_no_context_btf.c b/tools/testing/selftests/bpf/progs/dummy_no_context_btf.c
new file mode 100644
index 000000000000..5a1df4984dce
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/dummy_no_context_btf.c
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+
+/* A dummy program that does not reference context types in it's BTF */
+SEC("tc")
+__u32 dummy_prog(void *ctx)
+{
+ return 0;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/progs/dummy_sk_buff_user.c b/tools/testing/selftests/bpf/progs/dummy_sk_buff_user.c
new file mode 100644
index 000000000000..f271881bcbd0
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/dummy_sk_buff_user.c
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+
+/* A dummy program that references __sk_buff type in it's BTF,
+ * used by test_bpftool.py.
+ */
+SEC("tc")
+int sk_buff_user(struct __sk_buff *skb)
+{
+ return 0;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/test_bpftool.py b/tools/testing/selftests/bpf/test_bpftool.py
index 1c2408ee1f5d..3117f431dd92 100644
--- a/tools/testing/selftests/bpf/test_bpftool.py
+++ b/tools/testing/selftests/bpf/test_bpftool.py
@@ -8,6 +8,7 @@ import os
import socket
import subprocess
import unittest
+import io
# Add the source tree of bpftool and /usr/local/sbin to PATH
@@ -25,6 +26,10 @@ class UnprivilegedUserError(Exception):
pass
+class MissingDependencyError(Exception):
+ pass
+
+
def _bpftool(args, json=True):
_args = ["bpftool"]
if json:
@@ -63,12 +68,22 @@ DMESG_EMITTING_HELPERS = [
"bpf_trace_vprintk",
]
+DUMMY_SK_BUFF_USER_OBJ = cur_dir + "/dummy_sk_buff_user.bpf.o"
+DUMMY_NO_CONTEXT_BTF_OBJ = cur_dir + "/dummy_no_context_btf.bpf.o"
+
class TestBpftool(unittest.TestCase):
@classmethod
def setUpClass(cls):
if os.getuid() != 0:
raise UnprivilegedUserError(
"This test suite needs root privileges")
+ objs = [DUMMY_SK_BUFF_USER_OBJ,
+ DUMMY_NO_CONTEXT_BTF_OBJ]
+ for obj in objs:
+ if os.path.exists(obj):
+ continue
+ raise MissingDependencyError(
+ "File " + obj + " does not exist, make sure progs/*.c are compiled")
@default_iface
def test_feature_dev_json(self, iface):
@@ -172,3 +187,49 @@ class TestBpftool(unittest.TestCase):
res = bpftool(["feature", "probe", "macros"])
for pattern in expected_patterns:
self.assertRegex(res, pattern)
+
+ def assertStringsPresent(self, text, patterns):
+ pos = 0
+ for i, pat in enumerate(patterns):
+ m = text.find(pat, pos)
+ if m == -1:
+ with io.StringIO() as msg:
+ print("Can't find expected string:", file=msg)
+ for s in patterns[0:i]:
+ print(" MATCHED: " + s, file=msg)
+ print("NOT MATCHED: " + pat, file=msg)
+ print("", file=msg)
+ print("Searching in:", file=msg)
+ print(text, file=msg)
+ self.fail(msg.getvalue())
+ pos += len(pat)
+
+ # Load a small program that has some context types in it's BTF,
+ # verify that "bpftool btf dump file ... format c" emits
+ # preserve_static_offset attribute.
+ def test_c_dump_preserve_static_offset_present(self):
+ res = bpftool(["btf", "dump", "file", DUMMY_SK_BUFF_USER_OBJ, "format", "c"])
+ self.assertStringsPresent(res, [
+ "#if !defined(BPF_NO_PRESERVE_STATIC_OFFSET) && " +
+ "__has_attribute(preserve_static_offset)",
+ "#pragma clang attribute push " +
+ "(__attribute__((preserve_static_offset)), apply_to = record)",
+ "struct __sk_buff;",
+ "struct bpf_sock;",
+ "#pragma clang attribute pop",
+ "#endif /* BPF_NO_PRESERVE_STATIC_OFFSET */",
+ "#pragma clang attribute push " +
+ "(__attribute__((preserve_access_index)), apply_to = record)",
+ "struct __sk_buff {",
+ ])
+
+ # Load a small program that has no context types in it's BTF,
+ # verify that "bpftool btf dump file ... format c" does not emit
+ # preserve_static_offset attribute.
+ def test_c_dump_no_preserve_static_offset(self):
+ res = bpftool(["btf", "dump", "file", DUMMY_NO_CONTEXT_BTF_OBJ, "format", "c"])
+ self.assertNotRegex(res, "preserve_static_offset")
+ self.assertStringsPresent(res, [
+ "preserve_access_index",
+ "typedef unsigned int __u32;"
+ ])
--
2.42.1
