xref: /openbmc/linux/tools/perf/util/clockid.c (revision f21e49be)
1 // SPDX-License-Identifier: GPL-2.0
2 
3 #include <subcmd/parse-options.h>
4 #include <stdio.h>
5 #include <time.h>
6 #include <strings.h>
7 #include <linux/time64.h>
8 #include "debug.h"
9 #include "clockid.h"
10 #include "record.h"
11 
12 struct clockid_map {
13 	const char *name;
14 	int clockid;
15 };
16 
17 #define CLOCKID_MAP(n, c)	\
18 	{ .name = n, .clockid = (c), }
19 
20 #define CLOCKID_END	{ .name = NULL, }
21 
22 
23 /*
24  * Add the missing ones, we need to build on many distros...
25  */
26 #ifndef CLOCK_MONOTONIC_RAW
27 #define CLOCK_MONOTONIC_RAW 4
28 #endif
29 #ifndef CLOCK_BOOTTIME
30 #define CLOCK_BOOTTIME 7
31 #endif
32 #ifndef CLOCK_TAI
33 #define CLOCK_TAI 11
34 #endif
35 
36 static const struct clockid_map clockids[] = {
37 	/* available for all events, NMI safe */
38 	CLOCKID_MAP("monotonic", CLOCK_MONOTONIC),
39 	CLOCKID_MAP("monotonic_raw", CLOCK_MONOTONIC_RAW),
40 
41 	/* available for some events */
42 	CLOCKID_MAP("realtime", CLOCK_REALTIME),
43 	CLOCKID_MAP("boottime", CLOCK_BOOTTIME),
44 	CLOCKID_MAP("tai", CLOCK_TAI),
45 
46 	/* available for the lazy */
47 	CLOCKID_MAP("mono", CLOCK_MONOTONIC),
48 	CLOCKID_MAP("raw", CLOCK_MONOTONIC_RAW),
49 	CLOCKID_MAP("real", CLOCK_REALTIME),
50 	CLOCKID_MAP("boot", CLOCK_BOOTTIME),
51 
52 	CLOCKID_END,
53 };
54 
55 static int get_clockid_res(clockid_t clk_id, u64 *res_ns)
56 {
57 	struct timespec res;
58 
59 	*res_ns = 0;
60 	if (!clock_getres(clk_id, &res))
61 		*res_ns = res.tv_nsec + res.tv_sec * NSEC_PER_SEC;
62 	else
63 		pr_warning("WARNING: Failed to determine specified clock resolution.\n");
64 
65 	return 0;
66 }
67 
68 int parse_clockid(const struct option *opt, const char *str, int unset)
69 {
70 	struct record_opts *opts = (struct record_opts *)opt->value;
71 	const struct clockid_map *cm;
72 	const char *ostr = str;
73 
74 	if (unset) {
75 		opts->use_clockid = 0;
76 		return 0;
77 	}
78 
79 	/* no arg passed */
80 	if (!str)
81 		return 0;
82 
83 	/* no setting it twice */
84 	if (opts->use_clockid)
85 		return -1;
86 
87 	opts->use_clockid = true;
88 
89 	/* if its a number, we're done */
90 	if (sscanf(str, "%d", &opts->clockid) == 1)
91 		return get_clockid_res(opts->clockid, &opts->clockid_res_ns);
92 
93 	/* allow a "CLOCK_" prefix to the name */
94 	if (!strncasecmp(str, "CLOCK_", 6))
95 		str += 6;
96 
97 	for (cm = clockids; cm->name; cm++) {
98 		if (!strcasecmp(str, cm->name)) {
99 			opts->clockid = cm->clockid;
100 			return get_clockid_res(opts->clockid,
101 					       &opts->clockid_res_ns);
102 		}
103 	}
104 
105 	opts->use_clockid = false;
106 	ui__warning("unknown clockid %s, check man page\n", ostr);
107 	return -1;
108 }
109 
110 const char *clockid_name(clockid_t clk_id)
111 {
112 	const struct clockid_map *cm;
113 
114 	for (cm = clockids; cm->name; cm++) {
115 		if (cm->clockid == clk_id)
116 			return cm->name;
117 	}
118 	return "(not found)";
119 }
120