kernel_optimize_test/tools/perf/bench/syscall.c
Davidlohr Bueso c2a0820305 perf bench: Add basic syscall benchmark
The usefulness of having a standard way of testing syscall performance
has come up from time to time[0]. Furthermore, some of our testing
machinery (such as 'mmtests') already makes use of a simplified version
of the microbenchmark. This patch mainly takes the same idea to measure
syscall throughput compatible with 'perf-bench' via getppid(2), yet
without any of the additional template stuff from Ingo's version (based
on numa.c). The code is identical to what mmtests uses.

[0] https://lore.kernel.org/lkml/20160201074156.GA27156@gmail.com/

Committer notes:

Add mising stdlib.h and unistd.h to get the prototypes for exit() and
getppid().

Committer testing:

  $ perf bench
  Usage:
  	perf bench [<common options>] <collection> <benchmark> [<options>]

          # List of all available benchmark collections:

           sched: Scheduler and IPC benchmarks
         syscall: System call benchmarks
             mem: Memory access benchmarks
            numa: NUMA scheduling and MM benchmarks
           futex: Futex stressing benchmarks
           epoll: Epoll stressing benchmarks
       internals: Perf-internals benchmarks
             all: All benchmarks

  $
  $ perf bench syscall

          # List of available benchmarks for collection 'syscall':

           basic: Benchmark for basic getppid(2) calls
             all: Run all syscall benchmarks

  $ perf bench syscall basic
  # Running 'syscall/basic' benchmark:
  # Executed 10000000 getppid() calls
       Total time: 3.679 [sec]

         0.367957 usecs/op
          2717708 ops/sec
  $ perf bench syscall all
  # Running syscall/basic benchmark...
  # Executed 10000000 getppid() calls
       Total time: 3.644 [sec]

         0.364456 usecs/op
          2743815 ops/sec

  $

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20190308181747.l36zqz2avtivrr3c@linux-r8p5
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-07-28 08:50:48 -03:00

82 lines
1.7 KiB
C

/*
*
* syscall.c
*
* syscall: Benchmark for system call performance
*/
#include "../perf.h"
#include "../util/util.h"
#include <subcmd/parse-options.h>
#include "../builtin.h"
#include "bench.h"
#include <stdio.h>
#include <sys/time.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdlib.h>
#define LOOPS_DEFAULT 10000000
static int loops = LOOPS_DEFAULT;
static const struct option options[] = {
OPT_INTEGER('l', "loop", &loops, "Specify number of loops"),
OPT_END()
};
static const char * const bench_syscall_usage[] = {
"perf bench syscall <options>",
NULL
};
int bench_syscall_basic(int argc, const char **argv)
{
struct timeval start, stop, diff;
unsigned long long result_usec = 0;
int i;
argc = parse_options(argc, argv, options, bench_syscall_usage, 0);
gettimeofday(&start, NULL);
for (i = 0; i < loops; i++)
getppid();
gettimeofday(&stop, NULL);
timersub(&stop, &start, &diff);
switch (bench_format) {
case BENCH_FORMAT_DEFAULT:
printf("# Executed %'d getppid() calls\n", loops);
result_usec = diff.tv_sec * 1000000;
result_usec += diff.tv_usec;
printf(" %14s: %lu.%03lu [sec]\n\n", "Total time",
diff.tv_sec,
(unsigned long) (diff.tv_usec/1000));
printf(" %14lf usecs/op\n",
(double)result_usec / (double)loops);
printf(" %'14d ops/sec\n",
(int)((double)loops /
((double)result_usec / (double)1000000)));
break;
case BENCH_FORMAT_SIMPLE:
printf("%lu.%03lu\n",
diff.tv_sec,
(unsigned long) (diff.tv_usec / 1000));
break;
default:
/* reaching here is something disaster */
fprintf(stderr, "Unknown format:%d\n", bench_format);
exit(1);
break;
}
return 0;
}