linux/tools/perf/bench/kallsyms-parse.c
Ian Rogers 51876bd452 perf bench: Add kallsyms parsing
Add a benchmark for kallsyms parsing. Example output:

  Running 'internals/kallsyms-parse' benchmark:
  Average kallsyms__parse took: 103.971 ms (+- 0.121 ms)

Committer testing:

Test Machine: AMD Ryzen 5 3600X 6-Core Processor

  [root@five ~]# perf bench internals kallsyms-parse
  # Running 'internals/kallsyms-parse' benchmark:
    Average kallsyms__parse took: 79.692 ms (+- 0.101 ms)
  [root@five ~]# perf stat -r5 perf bench internals kallsyms-parse
  # Running 'internals/kallsyms-parse' benchmark:
    Average kallsyms__parse took: 80.563 ms (+- 0.079 ms)
  # Running 'internals/kallsyms-parse' benchmark:
    Average kallsyms__parse took: 81.046 ms (+- 0.155 ms)
  # Running 'internals/kallsyms-parse' benchmark:
    Average kallsyms__parse took: 80.874 ms (+- 0.104 ms)
  # Running 'internals/kallsyms-parse' benchmark:
    Average kallsyms__parse took: 81.173 ms (+- 0.133 ms)
  # Running 'internals/kallsyms-parse' benchmark:
    Average kallsyms__parse took: 81.169 ms (+- 0.074 ms)

   Performance counter stats for 'perf bench internals kallsyms-parse' (5 runs):

            8,093.54 msec task-clock                #    0.999 CPUs utilized            ( +-  0.14% )
               3,165      context-switches          #    0.391 K/sec                    ( +-  0.18% )
                  10      cpu-migrations            #    0.001 K/sec                    ( +- 23.13% )
                 744      page-faults               #    0.092 K/sec                    ( +-  0.21% )
      34,551,564,954      cycles                    #    4.269 GHz                      ( +-  0.05% )  (83.33%)
       1,160,584,308      stalled-cycles-frontend   #    3.36% frontend cycles idle     ( +-  1.60% )  (83.33%)
      14,974,323,985      stalled-cycles-backend    #   43.34% backend cycles idle      ( +-  0.24% )  (83.33%)
      58,712,905,705      instructions              #    1.70  insn per cycle
                                                    #    0.26  stalled cycles per insn  ( +-  0.01% )  (83.34%)
      14,136,433,778      branches                  # 1746.632 M/sec                    ( +-  0.01% )  (83.33%)
         141,943,217      branch-misses             #    1.00% of all branches          ( +-  0.04% )  (83.33%)

              8.1040 +- 0.0115 seconds time elapsed  ( +-  0.14% )

  [root@five ~]#

Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20200501221315.54715-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-05-05 16:35:32 -03:00

76 lines
1.7 KiB
C

// 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();
}