selfetest/bpf: Make some tests serial

Change tests that often fails in parallel execution mode to serial.

Signed-off-by: Yucong Sun <sunyucong@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211006185619.364369-15-fallentree@fb.com

selftests/bpf: Add remaining ASSERT_xxx() variants

Add ASSERT_TRUE/ASSERT_FALSE for conditions calculated with custom logic to
true/false. Also add remaining arithmetical assertions:
- ASSERT_LE -- less than or equal;
- ASSERT_GT -- greater than;
- ASSERT_GE -- greater than or equal.
This should cover most scenarios where people fall back to error-prone
CHECK()s.

Also extend ASSERT_ERR() to print out errno, in addition to direct error.

Also convert few CHECK() instances to ensure new ASSERT_xxx() variants work as
expected. Subsequent patch will also use ASSERT_TRUE/ASSERT_FALSE more
extensively.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Lorenz Bauer <lmb@cloudflare.com>
Link: https://lore.kernel.org/bpf/20210426192949.416837-2-andrii@kernel.org

bpf, selftests: Fix warning in snprintf_btf where system() call unchecked

On my systems system() calls are marked with warn_unused_result
apparently. So without error checking we get this warning,

./prog_tests/snprintf_btf.c:30:9: warning: ignoring return value
of ‘system’, declared with attribute warn_unused_result[-Wunused-result]

Also it seems like a good idea to check the return value anyways
to ensure ping exists even if its seems unlikely.

Fixes: 076a95f5aff2c ("selftests/bpf: Add bpf_snprintf_btf helper tests")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/160141006897.25201.12095049414156293265.stgit@john-Precision-5820-Tower

selftests/bpf: Fix unused-result warning in snprintf_btf.c

Daniel reports:

+ system("ping -c 1 127.0.0.1 > /dev/null");

This generates the following new warning when compiling BPF selftests:

[...]
EXT-OBJ [test_progs] cgroup_helpers.o
EXT-OBJ [test_progs] trace_helpers.o
EXT-OBJ [test_progs] network_helpers.o
EXT-OBJ [test_progs] testing_helpers.o
TEST-OBJ [test_progs] snprintf_btf.test.o
/root/bpf-next/tools/testing/selftests/bpf/prog_tests/snprintf_btf.c: In function ‘test_snprintf_btf’:
/root/bpf-next/tools/testing/selftests/bpf/prog_tests/snprintf_btf.c:30:2: warning: ignoring return value of ‘system’, declared with attribute warn_unused_result [-Wunused-result]
system("ping -c 1 127.0.0.1 > /dev/null");
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[...]

Fixes: 076a95f5aff2 ("selftests/bpf: Add bpf_snprintf_btf helper tests")
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601379151-21449-2-git-send-email-alan.maguire@oracle.com

selftests/bpf: Add bpf_snprintf_btf helper tests

Tests verifying snprintf()ing of various data structures,
flags combinations using a tp_btf program. Tests are skipped
if __builtin_btf_type_id is not available to retrieve BTF
type ids.

Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-5-git-send-email-alan.maguire@oracle.com