2 * You SHOULD NOT be including this unless you're vsyscall
3 * handling code or timekeeping internal code!
6 #ifndef _LINUX_TIMEKEEPER_INTERNAL_H
7 #define _LINUX_TIMEKEEPER_INTERNAL_H
9 #include <linux/clocksource.h>
10 #include <linux/jiffies.h>
11 #include <linux/time.h>
14 * struct tk_read_base - base structure for timekeeping readout
15 * @clock: Current clocksource used for timekeeping.
16 * @read: Read function of @clock
17 * @mask: Bitmask for two's complement subtraction of non 64bit clocks
18 * @cycle_last: @clock cycle value at last update
19 * @mult: (NTP adjusted) multiplier for scaled math conversion
20 * @shift: Shift value for scaled math conversion
21 * @xtime_nsec: Shifted (fractional) nano seconds offset for readout
22 * @base: ktime_t (nanoseconds) base time for readout
24 * This struct has size 56 byte on 64 bit. Together with a seqcount it
25 * occupies a single 64byte cache line.
27 * The struct is separate from struct timekeeper as it is also used
28 * for a fast NMI safe accessors.
31 struct clocksource
*clock
;
32 cycle_t (*read
)(struct clocksource
*cs
);
42 * struct timekeeper - Structure holding internal timekeeping values.
43 * @tkr_mono: The readout base structure for CLOCK_MONOTONIC
44 * @tkr_raw: The readout base structure for CLOCK_MONOTONIC_RAW
45 * @xtime_sec: Current CLOCK_REALTIME time in seconds
46 * @ktime_sec: Current CLOCK_MONOTONIC time in seconds
47 * @wall_to_monotonic: CLOCK_REALTIME to CLOCK_MONOTONIC offset
48 * @offs_real: Offset clock monotonic -> clock realtime
49 * @offs_boot: Offset clock monotonic -> clock boottime
50 * @offs_tai: Offset clock monotonic -> clock tai
51 * @tai_offset: The current UTC to TAI offset in seconds
52 * @clock_was_set_seq: The sequence number of clock was set events
53 * @cs_was_changed_seq: The sequence number of clocksource change events
54 * @next_leap_ktime: CLOCK_MONOTONIC time value of a pending leap-second
55 * @raw_time: Monotonic raw base time in timespec64 format
56 * @cycle_interval: Number of clock cycles in one NTP interval
57 * @xtime_interval: Number of clock shifted nano seconds in one NTP
59 * @xtime_remainder: Shifted nano seconds left over when rounding
61 * @raw_interval: Raw nano seconds accumulated per NTP interval.
62 * @ntp_error: Difference between accumulated time and NTP time in ntp
63 * shifted nano seconds.
64 * @ntp_error_shift: Shift conversion between clock shifted nano seconds and
65 * ntp shifted nano seconds.
66 * @last_warning: Warning ratelimiter (DEBUG_TIMEKEEPING)
67 * @underflow_seen: Underflow warning flag (DEBUG_TIMEKEEPING)
68 * @overflow_seen: Overflow warning flag (DEBUG_TIMEKEEPING)
70 * Note: For timespec(64) based interfaces wall_to_monotonic is what
71 * we need to add to xtime (or xtime corrected for sub jiffie times)
72 * to get to monotonic time. Monotonic is pegged at zero at system
73 * boot time, so wall_to_monotonic will be negative, however, we will
74 * ALWAYS keep the tv_nsec part positive so we can use the usual
77 * wall_to_monotonic is moved after resume from suspend for the
78 * monotonic time not to jump. We need to add total_sleep_time to
79 * wall_to_monotonic to get the real boot based time offset.
81 * wall_to_monotonic is no longer the boot time, getboottime must be
85 struct tk_read_base tkr_mono
;
86 struct tk_read_base tkr_raw
;
88 unsigned long ktime_sec
;
89 struct timespec64 wall_to_monotonic
;
94 unsigned int clock_was_set_seq
;
95 u8 cs_was_changed_seq
;
96 ktime_t next_leap_ktime
;
97 struct timespec64 raw_time
;
99 /* The following members are for timekeeping internal use */
100 cycle_t cycle_interval
;
104 /* The ntp_tick_length() value currently being used.
105 * This cached copy ensures we consistently apply the tick
106 * length for an entire tick, as ntp_tick_length may change
107 * mid-tick, and we don't want to apply that new value to
108 * the tick in progress.
111 /* Difference between accumulated time and NTP time in ntp
112 * shifted nano seconds. */
116 #ifdef CONFIG_DEBUG_TIMEKEEPING
119 * These simple flag variables are managed
120 * without locks, which is racy, but they are
121 * ok since we don't really care about being
122 * super precise about how many events were
123 * seen, just that a problem was observed.
130 #ifdef CONFIG_GENERIC_TIME_VSYSCALL
132 extern void update_vsyscall(struct timekeeper
*tk
);
133 extern void update_vsyscall_tz(void);
135 #elif defined(CONFIG_GENERIC_TIME_VSYSCALL_OLD)
137 extern void update_vsyscall_old(struct timespec
*ts
, struct timespec
*wtm
,
138 struct clocksource
*c
, u32 mult
,
140 extern void update_vsyscall_tz(void);
144 static inline void update_vsyscall(struct timekeeper
*tk
)
147 static inline void update_vsyscall_tz(void)
152 #endif /* _LINUX_TIMEKEEPER_INTERNAL_H */