1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Benchmark of /proc/kallsyms parsing.
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Copyright 2020 Google LLC.
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun #include <stdlib.h>
8*4882a593Smuzhiyun #include "bench.h"
9*4882a593Smuzhiyun #include "../util/stat.h"
10*4882a593Smuzhiyun #include <linux/time64.h>
11*4882a593Smuzhiyun #include <subcmd/parse-options.h>
12*4882a593Smuzhiyun #include <symbol/kallsyms.h>
13*4882a593Smuzhiyun
14*4882a593Smuzhiyun static unsigned int iterations = 100;
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun static const struct option options[] = {
17*4882a593Smuzhiyun OPT_UINTEGER('i', "iterations", &iterations,
18*4882a593Smuzhiyun "Number of iterations used to compute average"),
19*4882a593Smuzhiyun OPT_END()
20*4882a593Smuzhiyun };
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun static const char *const bench_usage[] = {
23*4882a593Smuzhiyun "perf bench internals kallsyms-parse <options>",
24*4882a593Smuzhiyun NULL
25*4882a593Smuzhiyun };
26*4882a593Smuzhiyun
bench_process_symbol(void * arg __maybe_unused,const char * name __maybe_unused,char type __maybe_unused,u64 start __maybe_unused)27*4882a593Smuzhiyun static int bench_process_symbol(void *arg __maybe_unused,
28*4882a593Smuzhiyun const char *name __maybe_unused,
29*4882a593Smuzhiyun char type __maybe_unused,
30*4882a593Smuzhiyun u64 start __maybe_unused)
31*4882a593Smuzhiyun {
32*4882a593Smuzhiyun return 0;
33*4882a593Smuzhiyun }
34*4882a593Smuzhiyun
do_kallsyms_parse(void)35*4882a593Smuzhiyun static int do_kallsyms_parse(void)
36*4882a593Smuzhiyun {
37*4882a593Smuzhiyun struct timeval start, end, diff;
38*4882a593Smuzhiyun u64 runtime_us;
39*4882a593Smuzhiyun unsigned int i;
40*4882a593Smuzhiyun double time_average, time_stddev;
41*4882a593Smuzhiyun int err;
42*4882a593Smuzhiyun struct stats time_stats;
43*4882a593Smuzhiyun
44*4882a593Smuzhiyun init_stats(&time_stats);
45*4882a593Smuzhiyun
46*4882a593Smuzhiyun for (i = 0; i < iterations; i++) {
47*4882a593Smuzhiyun gettimeofday(&start, NULL);
48*4882a593Smuzhiyun err = kallsyms__parse("/proc/kallsyms", NULL,
49*4882a593Smuzhiyun bench_process_symbol);
50*4882a593Smuzhiyun if (err)
51*4882a593Smuzhiyun return err;
52*4882a593Smuzhiyun
53*4882a593Smuzhiyun gettimeofday(&end, NULL);
54*4882a593Smuzhiyun timersub(&end, &start, &diff);
55*4882a593Smuzhiyun runtime_us = diff.tv_sec * USEC_PER_SEC + diff.tv_usec;
56*4882a593Smuzhiyun update_stats(&time_stats, runtime_us);
57*4882a593Smuzhiyun }
58*4882a593Smuzhiyun
59*4882a593Smuzhiyun time_average = avg_stats(&time_stats) / USEC_PER_MSEC;
60*4882a593Smuzhiyun time_stddev = stddev_stats(&time_stats) / USEC_PER_MSEC;
61*4882a593Smuzhiyun printf(" Average kallsyms__parse took: %.3f ms (+- %.3f ms)\n",
62*4882a593Smuzhiyun time_average, time_stddev);
63*4882a593Smuzhiyun return 0;
64*4882a593Smuzhiyun }
65*4882a593Smuzhiyun
bench_kallsyms_parse(int argc,const char ** argv)66*4882a593Smuzhiyun int bench_kallsyms_parse(int argc, const char **argv)
67*4882a593Smuzhiyun {
68*4882a593Smuzhiyun argc = parse_options(argc, argv, options, bench_usage, 0);
69*4882a593Smuzhiyun if (argc) {
70*4882a593Smuzhiyun usage_with_options(bench_usage, options);
71*4882a593Smuzhiyun exit(EXIT_FAILURE);
72*4882a593Smuzhiyun }
73*4882a593Smuzhiyun
74*4882a593Smuzhiyun return do_kallsyms_parse();
75*4882a593Smuzhiyun }
76