1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
|
/*
* Copyright (C) 2024-2025 Colin Ian King.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#include "stress-ng.h"
#include "core-clocksource.h"
#include <ctype.h>
#if defined(__linux__)
static inline void stress_clocksource_tolower(char *str)
{
unsigned char ch;
while ((ch = (unsigned char)*str)) {
if (isupper(ch))
*str = (char)tolower(ch);
str++;
}
}
#endif
/*
* stress_clocksource_check()
* check the clocksource being used, warn if the less accurate
* HPET is being used
*/
void stress_clocksource_check(void)
{
#if defined(__linux__)
DIR *dir;
struct dirent *entry;
static bool warned = false;
static const char dirname[] = "/sys/devices/system/clocksource";
if (warned)
return;
dir = opendir(dirname);
if (!dir)
return;
while ((entry = readdir(dir))) {
char path[PATH_MAX];
char buf[256];
ssize_t ret;
if (strncmp(entry->d_name, "clocksource", 11))
continue;
(void)snprintf(path, sizeof(path), "%s/%s/current_clocksource", dirname, entry->d_name);
ret = stress_system_read(path, buf, sizeof(buf));
if (ret > 0) {
stress_clocksource_tolower(buf);
if (strncmp(buf, "hpet", 4) == 0) {
pr_warn("WARNING! using HPET clocksource (refer to %s/%s), this may impact "
"benchmarking performance\n", dirname, entry->d_name);
warned = true;
}
}
}
(void)closedir(dir);
#endif
}
|
