Re: [PATCH v4 bpf-next 2/3] veristat: add -d debug mode option to see debug libbpf log

[Eduard Zingerman <eddyz87@gmail.com>]

On Mon, 2023-03-27 at 11:52 -0700, Andrii Nakryiko wrote:
> Add -d option to allow requesting libbpf debug logs from veristat.
> 
> Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
> ---
>  tools/testing/selftests/bpf/veristat.c | 8 +++++++-
>  1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/testing/selftests/bpf/veristat.c b/tools/testing/selftests/bpf/veristat.c
> index 83231456d3c5..263df32fbda8 100644
> --- a/tools/testing/selftests/bpf/veristat.c
> +++ b/tools/testing/selftests/bpf/veristat.c
> @@ -135,6 +135,7 @@ static struct env {
>  	char **filenames;
>  	int filename_cnt;
>  	bool verbose;
> +	bool debug;
>  	bool quiet;
>  	int log_level;

Nitpick:
  it is now three booleans that control verbosity level, would it be
  better to use numerical level instead?

>  	enum resfmt out_fmt;
> @@ -169,7 +170,7 @@ static int libbpf_print_fn(enum libbpf_print_level level, const char *format, va
>  {
>  	if (!env.verbose)
>  		return 0;
> -	if (level == LIBBPF_DEBUG /* && !env.verbose */)
> +	if (level == LIBBPF_DEBUG  && !env.debug)
>  		return 0;
>  	return vfprintf(stderr, format, args);
>  }
> @@ -186,6 +187,7 @@ static const struct argp_option opts[] = {
>  	{ NULL, 'h', NULL, OPTION_HIDDEN, "Show the full help" },
>  	{ "verbose", 'v', NULL, 0, "Verbose mode" },
>  	{ "log-level", 'l', "LEVEL", 0, "Verifier log level (default 0 for normal mode, 1 for verbose mode)" },
> +	{ "debug", 'd', NULL, 0, "Debug mode (turns on libbpf debug logging)" },
>  	{ "quiet", 'q', NULL, 0, "Quiet mode" },
>  	{ "emit", 'e', "SPEC", 0, "Specify stats to be emitted" },
>  	{ "sort", 's', "SPEC", 0, "Specify sort order" },
> @@ -212,6 +214,10 @@ static error_t parse_arg(int key, char *arg, struct argp_state *state)
>  	case 'v':
>  		env.verbose = true;
>  		break;
> +	case 'd':
> +		env.debug = true;
> +		env.verbose = true;
> +		break;
>  	case 'q':
>  		env.quiet = true;
>  		break;