> On Jan 9, 2020, at 2:09 PM, Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx> wrote:
>
> On Thu, Jan 09, 2020 at 09:27:26AM -0800, Song Liu wrote:
>> On Wed, Jan 8, 2020 at 10:39 PM Alexei Starovoitov <ast@xxxxxxxxxx> wrote:
>>>
>>> test_global_func[12] - check 512 stack limit.
>>> test_global_func[34] - check 8 frame call chain limit.
>>> test_global_func5 - check that non-ctx pointer cannot be passed into
>>> a function that expects context.
>>> test_global_func6 - check that ctx pointer is unmodified.
>>>
>>> Signed-off-by: Alexei Starovoitov <ast@xxxxxxxxxx>
>>
>> Acked-by: Song Liu <songliubraving@xxxxxx>
>>
>>> ---
>>> .../bpf/prog_tests/test_global_funcs.c | 81 +++++++++++++++++++
>>> .../selftests/bpf/progs/test_global_func1.c | 45 +++++++++++
>>> .../selftests/bpf/progs/test_global_func2.c | 4 +
>>> .../selftests/bpf/progs/test_global_func3.c | 65 +++++++++++++++
>>> .../selftests/bpf/progs/test_global_func4.c | 4 +
>>> .../selftests/bpf/progs/test_global_func5.c | 31 +++++++
>>> .../selftests/bpf/progs/test_global_func6.c | 31 +++++++
>>> 7 files changed, 261 insertions(+)
>>> create mode 100644 tools/testing/selftests/bpf/prog_tests/test_global_funcs.c
>>> create mode 100644 tools/testing/selftests/bpf/progs/test_global_func1.c
>>> create mode 100644 tools/testing/selftests/bpf/progs/test_global_func2.c
>>> create mode 100644 tools/testing/selftests/bpf/progs/test_global_func3.c
>>> create mode 100644 tools/testing/selftests/bpf/progs/test_global_func4.c
>>> create mode 100644 tools/testing/selftests/bpf/progs/test_global_func5.c
>>> create mode 100644 tools/testing/selftests/bpf/progs/test_global_func6.c
>>>
>>> diff --git a/tools/testing/selftests/bpf/prog_tests/test_global_funcs.c b/tools/testing/selftests/bpf/prog_tests/test_global_funcs.c
>>> new file mode 100644
>>> index 000000000000..bc588fa87d65
>>> --- /dev/null
>>> +++ b/tools/testing/selftests/bpf/prog_tests/test_global_funcs.c
>>> @@ -0,0 +1,81 @@
>>> +// SPDX-License-Identifier: GPL-2.0
>>> +/* Copyright (c) 2020 Facebook */
>>> +#include <test_progs.h>
>>> +
>>> +const char *err_str;
>>> +bool found;
>>> +
>>> +static int libbpf_debug_print(enum libbpf_print_level level,
>>> + const char *format, va_list args)
>>> +{
>>> + char *log_buf;
>>> +
>>> + if (level != LIBBPF_WARN ||
>>> + strcmp(format, "libbpf: \n%s\n")) {
>>> + vprintf(format, args);
>>> + return 0;
>>> + }
>>> +
>>> + log_buf = va_arg(args, char *);
>>> + if (!log_buf)
>>> + goto out;
>>> + if (strstr(log_buf, err_str) == 0)
>>> + found = true;
>>> +out:
>>> + printf(format, log_buf);
>>> + return 0;
>>> +}
>>
>> libbpf_debug_print() looks very useful. Maybe we can move it to some
>> header files?
>
> I think it's hack that goes deep into libbpf internals that should be
> discouraged. It's clearly very useful for selftests, but imo libbpf's log_buf
> api should be redesigned instead. It's imo the worst part of the library.
Yeah, those global variables don't look good.
Song
