linux/tools/testing/selftests/bpf/test_bpftool.py
Dave Marchevsky 4190c299a4 bpftool: Only probe trace_vprintk feature in 'full' mode
Since commit 368cb0e7cd ("bpftool: Make probes which emit dmesg
warnings optional"), some helpers aren't probed by bpftool unless
`full` arg is added to `bpftool feature probe`.

bpf_trace_vprintk can emit dmesg warnings when probed, so include it.

Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210917182911.2426606-7-davemarchevsky@fb.com
2021-09-17 14:02:05 -07:00

175 lines
5.3 KiB
Python

# SPDX-License-Identifier: GPL-2.0
# Copyright (c) 2020 SUSE LLC.
import collections
import functools
import json
import os
import socket
import subprocess
import unittest
# Add the source tree of bpftool and /usr/local/sbin to PATH
cur_dir = os.path.dirname(os.path.realpath(__file__))
bpftool_dir = os.path.abspath(os.path.join(cur_dir, "..", "..", "..", "..",
"tools", "bpf", "bpftool"))
os.environ["PATH"] = bpftool_dir + ":/usr/local/sbin:" + os.environ["PATH"]
class IfaceNotFoundError(Exception):
pass
class UnprivilegedUserError(Exception):
pass
def _bpftool(args, json=True):
_args = ["bpftool"]
if json:
_args.append("-j")
_args.extend(args)
return subprocess.check_output(_args)
def bpftool(args):
return _bpftool(args, json=False).decode("utf-8")
def bpftool_json(args):
res = _bpftool(args)
return json.loads(res)
def get_default_iface():
for iface in socket.if_nameindex():
if iface[1] != "lo":
return iface[1]
raise IfaceNotFoundError("Could not find any network interface to probe")
def default_iface(f):
@functools.wraps(f)
def wrapper(*args, **kwargs):
iface = get_default_iface()
return f(*args, iface, **kwargs)
return wrapper
DMESG_EMITTING_HELPERS = [
"bpf_probe_write_user",
"bpf_trace_printk",
"bpf_trace_vprintk",
]
class TestBpftool(unittest.TestCase):
@classmethod
def setUpClass(cls):
if os.getuid() != 0:
raise UnprivilegedUserError(
"This test suite needs root privileges")
@default_iface
def test_feature_dev_json(self, iface):
unexpected_helpers = DMESG_EMITTING_HELPERS
expected_keys = [
"syscall_config",
"program_types",
"map_types",
"helpers",
"misc",
]
res = bpftool_json(["feature", "probe", "dev", iface])
# Check if the result has all expected keys.
self.assertCountEqual(res.keys(), expected_keys)
# Check if unexpected helpers are not included in helpers probes
# result.
for helpers in res["helpers"].values():
for unexpected_helper in unexpected_helpers:
self.assertNotIn(unexpected_helper, helpers)
def test_feature_kernel(self):
test_cases = [
bpftool_json(["feature", "probe", "kernel"]),
bpftool_json(["feature", "probe"]),
bpftool_json(["feature"]),
]
unexpected_helpers = DMESG_EMITTING_HELPERS
expected_keys = [
"syscall_config",
"system_config",
"program_types",
"map_types",
"helpers",
"misc",
]
for tc in test_cases:
# Check if the result has all expected keys.
self.assertCountEqual(tc.keys(), expected_keys)
# Check if unexpected helpers are not included in helpers probes
# result.
for helpers in tc["helpers"].values():
for unexpected_helper in unexpected_helpers:
self.assertNotIn(unexpected_helper, helpers)
def test_feature_kernel_full(self):
test_cases = [
bpftool_json(["feature", "probe", "kernel", "full"]),
bpftool_json(["feature", "probe", "full"]),
]
expected_helpers = DMESG_EMITTING_HELPERS
for tc in test_cases:
# Check if expected helpers are included at least once in any
# helpers list for any program type. Unfortunately we cannot assume
# that they will be included in all program types or a specific
# subset of programs. It depends on the kernel version and
# configuration.
found_helpers = False
for helpers in tc["helpers"].values():
if all(expected_helper in helpers
for expected_helper in expected_helpers):
found_helpers = True
break
self.assertTrue(found_helpers)
def test_feature_kernel_full_vs_not_full(self):
full_res = bpftool_json(["feature", "probe", "full"])
not_full_res = bpftool_json(["feature", "probe"])
not_full_set = set()
full_set = set()
for helpers in full_res["helpers"].values():
for helper in helpers:
full_set.add(helper)
for helpers in not_full_res["helpers"].values():
for helper in helpers:
not_full_set.add(helper)
self.assertCountEqual(full_set - not_full_set,
set(DMESG_EMITTING_HELPERS))
self.assertCountEqual(not_full_set - full_set, set())
def test_feature_macros(self):
expected_patterns = [
r"/\*\*\* System call availability \*\*\*/",
r"#define HAVE_BPF_SYSCALL",
r"/\*\*\* eBPF program types \*\*\*/",
r"#define HAVE.*PROG_TYPE",
r"/\*\*\* eBPF map types \*\*\*/",
r"#define HAVE.*MAP_TYPE",
r"/\*\*\* eBPF helper functions \*\*\*/",
r"#define HAVE.*HELPER",
r"/\*\*\* eBPF misc features \*\*\*/",
]
res = bpftool(["feature", "probe", "macros"])
for pattern in expected_patterns:
self.assertRegex(res, pattern)