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
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
|
// SPDX-License-Identifier: GPL-2.0
#define _GNU_SOURCE
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <poll.h>
#include <signal.h>
#define POWER_FLOOR_ENABLE_ATTRIBUTE "/sys/bus/pci/devices/0000:00:04.0/power_limits/power_floor_enable"
#define POWER_FLOOR_STATUS_ATTRIBUTE "/sys/bus/pci/devices/0000:00:04.0/power_limits/power_floor_status"
void power_floor_exit(int signum)
{
int fd;
/* Disable feature via sysfs knob */
fd = open(POWER_FLOOR_ENABLE_ATTRIBUTE, O_RDWR);
if (fd < 0) {
perror("Unable to open power floor enable file\n");
exit(1);
}
if (write(fd, "0\n", 2) < 0) {
perror("Can' disable power floor notifications\n");
exit(1);
}
printf("Disabled power floor notifications\n");
close(fd);
}
int main(int argc, char **argv)
{
struct pollfd ufd;
char status_str[3];
int fd, ret;
if (signal(SIGINT, power_floor_exit) == SIG_IGN)
signal(SIGINT, SIG_IGN);
if (signal(SIGHUP, power_floor_exit) == SIG_IGN)
signal(SIGHUP, SIG_IGN);
if (signal(SIGTERM, power_floor_exit) == SIG_IGN)
signal(SIGTERM, SIG_IGN);
/* Enable feature via sysfs knob */
fd = open(POWER_FLOOR_ENABLE_ATTRIBUTE, O_RDWR);
if (fd < 0) {
perror("Unable to open power floor enable file\n");
exit(1);
}
if (write(fd, "1\n", 2) < 0) {
perror("Can' enable power floor notifications\n");
exit(1);
}
close(fd);
printf("Enabled power floor notifications\n");
while (1) {
fd = open(POWER_FLOOR_STATUS_ATTRIBUTE, O_RDONLY);
if (fd < 0) {
perror("Unable to power floor status file\n");
exit(1);
}
if ((lseek(fd, 0L, SEEK_SET)) < 0) {
fprintf(stderr, "Failed to set pointer to beginning\n");
exit(1);
}
if (read(fd, status_str, sizeof(status_str)) < 0) {
fprintf(stderr, "Failed to read from:%s\n",
POWER_FLOOR_STATUS_ATTRIBUTE);
exit(1);
}
ufd.fd = fd;
ufd.events = POLLPRI;
ret = poll(&ufd, 1, -1);
if (ret < 0) {
perror("poll error");
exit(1);
} else if (ret == 0) {
printf("Poll Timeout\n");
} else {
if ((lseek(fd, 0L, SEEK_SET)) < 0) {
fprintf(stderr, "Failed to set pointer to beginning\n");
exit(1);
}
if (read(fd, status_str, sizeof(status_str)) < 0)
exit(0);
printf("power floor status: %s\n", status_str);
}
close(fd);
}
}
|
