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// SPDX-License-Identifier: GPL-2.0
/*
* Benchmark of /proc/kallsyms parsing.
*
* Copyright 2020 Google LLC.
*/
#include <stdlib.h>
#include "bench.h"
#include "../util/stat.h"
#include <linux/time64.h>
#include <subcmd/parse-options.h>
#include <symbol/kallsyms.h>
static unsigned int iterations = 100;
static const struct option options[] = {
OPT_UINTEGER('i', "iterations", &iterations,
"Number of iterations used to compute average"),
OPT_END()
};
static const char *const bench_usage[] = {
"perf bench internals kallsyms-parse <options>",
NULL
};
static int bench_process_symbol(void *arg __maybe_unused,
const char *name __maybe_unused,
char type __maybe_unused,
u64 start __maybe_unused)
{
return 0;
}
static int do_kallsyms_parse(void)
{
struct timeval start, end, diff;
u64 runtime_us;
unsigned int i;
double time_average, time_stddev;
int err;
struct stats time_stats;
init_stats(&time_stats);
for (i = 0; i < iterations; i++) {
gettimeofday(&start, NULL);
err = kallsyms__parse("/proc/kallsyms", NULL,
bench_process_symbol);
if (err)
return err;
gettimeofday(&end, NULL);
timersub(&end, &start, &diff);
runtime_us = diff.tv_sec * USEC_PER_SEC + diff.tv_usec;
update_stats(&time_stats, runtime_us);
}
time_average = avg_stats(&time_stats) / USEC_PER_MSEC;
time_stddev = stddev_stats(&time_stats) / USEC_PER_MSEC;
printf(" Average kallsyms__parse took: %.3f ms (+- %.3f ms)\n",
time_average, time_stddev);
return 0;
}
int bench_kallsyms_parse(int argc, const char **argv)
{
argc = parse_options(argc, argv, options, bench_usage, 0);
if (argc) {
usage_with_options(bench_usage, options);
exit(EXIT_FAILURE);
}
return do_kallsyms_parse();
}
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