Re: [PATCH rt-tests v5 04/13] cyclictest: Add JSON output feature

[John Kacur <jkacur@redhat.com>]

On Wed, 10 Feb 2021, Daniel Wagner wrote:

> Write the test results as JSON output to a file. This allows to
> simplifies any parsing later on.
> 
> Signed-off-by: Daniel Wagner <dwagner@suse.de>
> ---
>  src/cyclictest/cyclictest.c | 46 ++++++++++++++++++++++++++++++++++++-
>  1 file changed, 45 insertions(+), 1 deletion(-)
> 
> diff --git a/src/cyclictest/cyclictest.c b/src/cyclictest/cyclictest.c
> index 7c45732c1553..3d0cf3f84b69 100644
> --- a/src/cyclictest/cyclictest.c
> +++ b/src/cyclictest/cyclictest.c
> @@ -11,6 +11,7 @@
>  #include <stdio.h>
>  #include <stdlib.h>
>  #include <stdint.h>
> +#include <inttypes.h>
>  #include <stdarg.h>
>  #include <unistd.h>
>  #include <fcntl.h>
> @@ -217,6 +218,7 @@ static struct timespec globalt;
>  
>  static char fifopath[MAX_PATH];
>  static char histfile[MAX_PATH];
> +static char outfile[MAX_PATH];
>  
>  static struct thread_param **parameters;
>  static struct thread_stat **statistics;
> @@ -838,6 +840,7 @@ static void display_help(int error)
>  	       "			   latency is hit. Useful for low bandwidth.\n"
>  	       "-N       --nsecs           print results in ns instead of us (default us)\n"
>  	       "-o RED   --oscope=RED      oscilloscope mode, reduce verbose output by RED\n"
> +	       "         --output=FILENAME write final results into FILENAME, JSON formatted\n"
>  	       "-p PRIO  --priority=PRIO   priority of highest prio thread\n"
>  	       "	 --policy=NAME     policy of measurement thread, where NAME may be one\n"
>  	       "                           of: other, normal, batch, idle, fifo or rr.\n"
> @@ -945,7 +948,7 @@ enum option_values {
>  	OPT_TRIGGER_NODES, OPT_UNBUFFERED, OPT_NUMA, OPT_VERBOSE,
>  	OPT_DBGCYCLIC, OPT_POLICY, OPT_HELP, OPT_NUMOPTS,
>  	OPT_ALIGNED, OPT_SECALIGNED, OPT_LAPTOP, OPT_SMI,
> -	OPT_TRACEMARK, OPT_POSIX_TIMERS,
> +	OPT_TRACEMARK, OPT_POSIX_TIMERS, OPT_OUTPUT
>  };
>  
>  /* Process commandline options */
> @@ -979,6 +982,7 @@ static void process_options(int argc, char *argv[])
>  			{"refresh_on_max",   no_argument,       NULL, OPT_REFRESH },
>  			{"nsecs",            no_argument,       NULL, OPT_NSECS },
>  			{"oscope",           required_argument, NULL, OPT_OSCOPE },
> +			{"output",           required_argument, NULL, OPT_OUTPUT },
>  			{"priority",         required_argument, NULL, OPT_PRIORITY },
>  			{"quiet",            no_argument,       NULL, OPT_QUIET },
>  			{"priospread",       no_argument,       NULL, OPT_PRIOSPREAD },
> @@ -1073,6 +1077,9 @@ static void process_options(int argc, char *argv[])
>  		case 'o':
>  		case OPT_OSCOPE:
>  			oscope_reduction = atoi(optarg); break;
> +		case OPT_OUTPUT:
> +			strncpy(outfile, optarg, strnlen(optarg, MAX_PATH-1));
> +			break;
>  		case 'p':
>  		case OPT_PRIORITY:
>  			priority = atoi(optarg);
> @@ -1690,6 +1697,40 @@ static void rstat_setup(void)
>  	return;
>  }
>  
> +static void write_stats(FILE *f, void *data)
> +{
> +	struct thread_param **par = parameters;
> +	unsigned int i, j, comma;
> +	struct thread_stat *s;
> +
> +	fprintf(f, "  \"num_threads\": %d,\n", num_threads);
> +	fprintf(f, "  \"resolution_in_ns\": %u,\n", use_nsecs);
> +	fprintf(f, "  \"thread\": {\n");
> +	for (i = 0; i < num_threads; i++) {
> +		fprintf(f, "    \"%u\": {\n", i);
> +
> +		fprintf(f, "      \"histogram\": {");
> +		s = par[i]->stats;
> +		for (j = 0, comma = 0; j < histogram; j++) {
> +			if (s->hist_array[j] == 0)
> +				continue;
> +			fprintf(f, "%s", comma ? ",\n" : "\n");
> +			fprintf(f, "        \"%u\": %" PRIu64,j, s->hist_array[j]);
> +			comma = 1;
> +		}
> +		if (comma)
> +			fprintf(f, "\n");
> +		fprintf(f, "      },\n");
> +		fprintf(f, "      \"cycles\": %" PRIu64 ",\n", s->cycles);
> +		fprintf(f, "      \"min\": %" PRIu64 ",\n", s->min);
> +		fprintf(f, "      \"max\": %" PRIu64 ",\n", s->max);
> +		fprintf(f, "      \"avg\": %.2f,\n", s->avg/s->cycles);
> +		fprintf(f, "      \"cpu\": %d,\n", par[i]->cpu);
> +		fprintf(f, "      \"node\": %d\n", par[i]->node);
> +		fprintf(f, "    }%s\n", i == num_threads - 1 ? "" : ",");
> +	}
> +	fprintf(f, "  }\n");
> +}
>  
>  int main(int argc, char **argv)
>  {
> @@ -2035,6 +2076,9 @@ int main(int argc, char **argv)
>  	if (!verbose && !quiet && refresh_on_max)
>  		printf("\033[%dB", num_threads + 2);
>  
> +	if (strlen(outfile) != 0)
> +		rt_write_json(outfile, argc, argv, write_stats, NULL);
> +
>  	if (quiet)
>  		quiet = 2;
>  	for (i = 0; i < num_threads; i++) {
> -- 
> 2.30.0
> 
> 
   - Added a space after a comma in fprintf
    Signed-off-by: John Kacur <jkacur@redhat.com>