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1/*
2 * You SHOULD NOT be including this unless you're vsyscall
3 * handling code or timekeeping internal code!
4 */
5
6#ifndef _LINUX_TIMEKEEPER_INTERNAL_H
7#define _LINUX_TIMEKEEPER_INTERNAL_H
8
9#include <linux/clocksource.h>
10#include <linux/jiffies.h>
11#include <linux/time.h>
12
13/* Structure holding internal timekeeping values. */
14struct timekeeper {
15 /* Current clocksource used for timekeeping. */
16 struct clocksource *clock;
17 /* NTP adjusted clock multiplier */
18 u32 mult;
19 /* The shift value of the current clocksource. */
20 u32 shift;
21 /* Number of clock cycles in one NTP interval. */
22 cycle_t cycle_interval;
23 /* Number of clock shifted nano seconds in one NTP interval. */
24 u64 xtime_interval;
25 /* shifted nano seconds left over when rounding cycle_interval */
26 s64 xtime_remainder;
27 /* Raw nano seconds accumulated per NTP interval. */
28 u32 raw_interval;
29
30 /* Current CLOCK_REALTIME time in seconds */
31 u64 xtime_sec;
32 /* Clock shifted nano seconds */
33 u64 xtime_nsec;
34
35 /* Difference between accumulated time and NTP time in ntp
36 * shifted nano seconds. */
37 s64 ntp_error;
38 /* Shift conversion between clock shifted nano seconds and
39 * ntp shifted nano seconds. */
40 u32 ntp_error_shift;
41
42 /*
43 * wall_to_monotonic is what we need to add to xtime (or xtime corrected
44 * for sub jiffie times) to get to monotonic time. Monotonic is pegged
45 * at zero at system boot time, so wall_to_monotonic will be negative,
46 * however, we will ALWAYS keep the tv_nsec part positive so we can use
47 * the usual normalization.
48 *
49 * wall_to_monotonic is moved after resume from suspend for the
50 * monotonic time not to jump. We need to add total_sleep_time to
51 * wall_to_monotonic to get the real boot based time offset.
52 *
53 * - wall_to_monotonic is no longer the boot time, getboottime must be
54 * used instead.
55 */
56 struct timespec wall_to_monotonic;
57 /* Offset clock monotonic -> clock realtime */
58 ktime_t offs_real;
59 /* time spent in suspend */
60 struct timespec total_sleep_time;
61 /* Offset clock monotonic -> clock boottime */
62 ktime_t offs_boot;
63 /* The raw monotonic time for the CLOCK_MONOTONIC_RAW posix clock. */
64 struct timespec raw_time;
65 /* Seqlock for all timekeeper values */
66 seqlock_t lock;
67};
68
69static inline struct timespec tk_xtime(struct timekeeper *tk)
70{
71 struct timespec ts;
72
73 ts.tv_sec = tk->xtime_sec;
74 ts.tv_nsec = (long)(tk->xtime_nsec >> tk->shift);
75 return ts;
76}
77
78
79#ifdef CONFIG_GENERIC_TIME_VSYSCALL
80
81extern void update_vsyscall(struct timekeeper *tk);
82extern void update_vsyscall_tz(void);
83
84#elif defined(CONFIG_GENERIC_TIME_VSYSCALL_OLD)
85
86extern void update_vsyscall_old(struct timespec *ts, struct timespec *wtm,
87 struct clocksource *c, u32 mult);
88extern void update_vsyscall_tz(void);
89
90static inline void update_vsyscall(struct timekeeper *tk)
91{
92 struct timespec xt;
93
94 xt = tk_xtime(tk);
95 update_vsyscall_old(&xt, &tk->wall_to_monotonic, tk->clock, tk->mult);
96}
97
98#else
99
100static inline void update_vsyscall(struct timekeeper *tk)
101{
102}
103static inline void update_vsyscall_tz(void)
104{
105}
106#endif
107
108#endif /* _LINUX_TIMEKEEPER_INTERNAL_H */