xref: /openbmc/linux/tools/perf/bench/syscall.c (revision 842ed298)
1 /*
2  *
3  * syscall.c
4  *
5  * syscall: Benchmark for system call performance
6  */
7 #include "../perf.h"
8 #include "../util/util.h"
9 #include <subcmd/parse-options.h>
10 #include "../builtin.h"
11 #include "bench.h"
12 
13 #include <stdio.h>
14 #include <sys/time.h>
15 #include <sys/syscall.h>
16 #include <sys/types.h>
17 #include <unistd.h>
18 #include <stdlib.h>
19 
20 #define LOOPS_DEFAULT 10000000
21 static	int loops = LOOPS_DEFAULT;
22 
23 static const struct option options[] = {
24 	OPT_INTEGER('l', "loop",	&loops,		"Specify number of loops"),
25 	OPT_END()
26 };
27 
28 static const char * const bench_syscall_usage[] = {
29 	"perf bench syscall <options>",
30 	NULL
31 };
32 
33 int bench_syscall_basic(int argc, const char **argv)
34 {
35 	struct timeval start, stop, diff;
36 	unsigned long long result_usec = 0;
37 	int i;
38 
39 	argc = parse_options(argc, argv, options, bench_syscall_usage, 0);
40 
41 	gettimeofday(&start, NULL);
42 
43 	for (i = 0; i < loops; i++)
44 		getppid();
45 
46 	gettimeofday(&stop, NULL);
47 	timersub(&stop, &start, &diff);
48 
49 	switch (bench_format) {
50 	case BENCH_FORMAT_DEFAULT:
51 		printf("# Executed %'d getppid() calls\n", loops);
52 
53 		result_usec = diff.tv_sec * 1000000;
54 		result_usec += diff.tv_usec;
55 
56 		printf(" %14s: %lu.%03lu [sec]\n\n", "Total time",
57 		       diff.tv_sec,
58 		       (unsigned long) (diff.tv_usec/1000));
59 
60 		printf(" %14lf usecs/op\n",
61 		       (double)result_usec / (double)loops);
62 		printf(" %'14d ops/sec\n",
63 		       (int)((double)loops /
64 			     ((double)result_usec / (double)1000000)));
65 		break;
66 
67 	case BENCH_FORMAT_SIMPLE:
68 		printf("%lu.%03lu\n",
69 		       diff.tv_sec,
70 		       (unsigned long) (diff.tv_usec / 1000));
71 		break;
72 
73 	default:
74 		/* reaching here is something disaster */
75 		fprintf(stderr, "Unknown format:%d\n", bench_format);
76 		exit(1);
77 		break;
78 	}
79 
80 	return 0;
81 }
82