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
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
|
/* Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <errno.h>
#include <time.h>
#include <sys/time.h>
#include <libc-internal.h>
#include <ldsodefs.h>
#if HP_TIMING_AVAIL
/* Clock frequency of the processor. We make it a 64-bit variable
because some jokers are already playing with processors with more
than 4GHz. */
static hp_timing_t freq;
/* This function is defined in the thread library. */
extern void __pthread_clock_settime (clockid_t clock_id, hp_timing_t offset)
__attribute__ ((__weak__));
#endif
/* Set CLOCK to value TP. */
int
clock_settime (clockid_t clock_id, const struct timespec *tp)
{
int retval;
/* Make sure the time cvalue is OK. */
if (tp->tv_nsec < 0 || tp->tv_nsec >= 1000000000)
{
__set_errno (EINVAL);
return -1;
}
switch (clock_id)
{
#define HANDLE_REALTIME \
do { \
struct timeval tv; \
TIMESPEC_TO_TIMEVAL (&tv, tp); \
\
retval = settimeofday (&tv, NULL); \
} while (0)
#ifdef SYSDEP_SETTIME
SYSDEP_SETTIME;
#endif
#ifndef HANDLED_REALTIME
case CLOCK_REALTIME:
HANDLE_REALTIME;
break;
#endif
default:
#if HP_TIMING_AVAIL
if ((clock_id & ((1 << CLOCK_IDFIELD_SIZE) - 1))
!= CLOCK_THREAD_CPUTIME_ID)
#endif
{
__set_errno (EINVAL);
retval = -1;
break;
}
#if HP_TIMING_AVAIL
/* FALLTHROUGH. */
case CLOCK_PROCESS_CPUTIME_ID:
{
hp_timing_t tsc;
hp_timing_t usertime;
/* First thing is to get the current time. */
HP_TIMING_NOW (tsc);
if (__builtin_expect (freq == 0, 0))
{
/* This can only happen if we haven't initialized the `freq'
variable yet. Do this now. We don't have to protect this
code against multiple execution since all of them should
lead to the same result. */
freq = __get_clockfreq ();
if (__builtin_expect (freq == 0, 0))
{
/* Something went wrong. */
retval = -1;
break;
}
}
/* Convert the user-provided time into CPU ticks. */
usertime = tp->tv_sec * freq + (tp->tv_nsec * freq) / 1000000000ull;
/* Determine the offset and use it as the new base value. */
if (clock_id == CLOCK_PROCESS_CPUTIME_ID
|| __pthread_clock_settime == NULL)
GL(dl_cpuclock_offset) = tsc - usertime;
else
__pthread_clock_settime (clock_id, tsc - usertime);
retval = 0;
}
break;
#endif
}
return retval;
}
|
