Commit | Line | Data |
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d7b4202e JS |
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 | ||
d28ede83 TG |
13 | /** |
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_mono: ktime_t (nanoseconds) base time for readout | |
3fdb14fd | 23 | * |
d28ede83 TG |
24 | * This struct has size 56 byte on 64 bit. Together with a seqcount it |
25 | * occupies a single 64byte cache line. | |
3fdb14fd | 26 | * |
d28ede83 TG |
27 | * The struct is separate from struct timekeeper as it is also used |
28 | * for a fast NMI safe accessor to clock monotonic. | |
3fdb14fd | 29 | */ |
d28ede83 | 30 | struct tk_read_base { |
d7b4202e | 31 | struct clocksource *clock; |
6d3aadf3 | 32 | cycle_t (*read)(struct clocksource *cs); |
6d3aadf3 | 33 | cycle_t mask; |
4a0e6377 | 34 | cycle_t cycle_last; |
d7b4202e | 35 | u32 mult; |
d7b4202e | 36 | u32 shift; |
3fdb14fd | 37 | u64 xtime_nsec; |
7c032df5 | 38 | ktime_t base_mono; |
d28ede83 | 39 | }; |
7c032df5 | 40 | |
d28ede83 TG |
41 | /** |
42 | * struct timekeeper - Structure holding internal timekeeping values. | |
43 | * @tkr: The readout base structure | |
44 | * @xtime_sec: Current CLOCK_REALTIME time in seconds | |
45 | * @wall_to_monotonic: CLOCK_REALTIME to CLOCK_MONOTONIC offset | |
46 | * @offs_real: Offset clock monotonic -> clock realtime | |
47 | * @offs_boot: Offset clock monotonic -> clock boottime | |
48 | * @offs_tai: Offset clock monotonic -> clock tai | |
49 | * @tai_offset: The current UTC to TAI offset in seconds | |
50 | * @base_raw: Monotonic raw base time in ktime_t format | |
51 | * @raw_time: Monotonic raw base time in timespec64 format | |
52 | * @cycle_interval: Number of clock cycles in one NTP interval | |
53 | * @xtime_interval: Number of clock shifted nano seconds in one NTP | |
54 | * interval. | |
55 | * @xtime_remainder: Shifted nano seconds left over when rounding | |
56 | * @cycle_interval | |
57 | * @raw_interval: Raw nano seconds accumulated per NTP interval. | |
58 | * @ntp_error: Difference between accumulated time and NTP time in ntp | |
59 | * shifted nano seconds. | |
60 | * @ntp_error_shift: Shift conversion between clock shifted nano seconds and | |
61 | * ntp shifted nano seconds. | |
62 | * | |
63 | * Note: For timespec(64) based interfaces wall_to_monotonic is what | |
64 | * we need to add to xtime (or xtime corrected for sub jiffie times) | |
65 | * to get to monotonic time. Monotonic is pegged at zero at system | |
66 | * boot time, so wall_to_monotonic will be negative, however, we will | |
67 | * ALWAYS keep the tv_nsec part positive so we can use the usual | |
68 | * normalization. | |
69 | * | |
70 | * wall_to_monotonic is moved after resume from suspend for the | |
71 | * monotonic time not to jump. We need to add total_sleep_time to | |
72 | * wall_to_monotonic to get the real boot based time offset. | |
73 | * | |
74 | * wall_to_monotonic is no longer the boot time, getboottime must be | |
75 | * used instead. | |
76 | */ | |
77 | struct timekeeper { | |
78 | struct tk_read_base tkr; | |
3fdb14fd | 79 | u64 xtime_sec; |
3fdb14fd | 80 | struct timespec64 wall_to_monotonic; |
3fdb14fd | 81 | ktime_t offs_real; |
3fdb14fd | 82 | ktime_t offs_boot; |
3fdb14fd | 83 | ktime_t offs_tai; |
3fdb14fd | 84 | s32 tai_offset; |
f519b1a2 | 85 | ktime_t base_raw; |
3fdb14fd TG |
86 | struct timespec64 raw_time; |
87 | ||
d28ede83 | 88 | /* The following members are for timekeeping internal use */ |
d7b4202e | 89 | cycle_t cycle_interval; |
d7b4202e | 90 | u64 xtime_interval; |
d7b4202e | 91 | s64 xtime_remainder; |
d7b4202e | 92 | u32 raw_interval; |
375f45b5 JS |
93 | /* The ntp_tick_length() value currently being used. |
94 | * This cached copy ensures we consistently apply the tick | |
95 | * length for an entire tick, as ntp_tick_length may change | |
96 | * mid-tick, and we don't want to apply that new value to | |
97 | * the tick in progress. | |
98 | */ | |
99 | u64 ntp_tick; | |
100 | /* Difference between accumulated time and NTP time in ntp | |
101 | * shifted nano seconds. */ | |
d7b4202e | 102 | s64 ntp_error; |
3fdb14fd | 103 | u32 ntp_error_shift; |
dc491596 | 104 | u32 ntp_err_mult; |
d7b4202e | 105 | }; |
189374ae | 106 | |
576094b7 JS |
107 | #ifdef CONFIG_GENERIC_TIME_VSYSCALL |
108 | ||
109 | extern void update_vsyscall(struct timekeeper *tk); | |
110 | extern void update_vsyscall_tz(void); | |
189374ae | 111 | |
576094b7 JS |
112 | #elif defined(CONFIG_GENERIC_TIME_VSYSCALL_OLD) |
113 | ||
114 | extern void update_vsyscall_old(struct timespec *ts, struct timespec *wtm, | |
4a0e6377 | 115 | struct clocksource *c, u32 mult, |
953dec21 | 116 | cycle_t cycle_last); |
189374ae | 117 | extern void update_vsyscall_tz(void); |
576094b7 | 118 | |
189374ae | 119 | #else |
576094b7 JS |
120 | |
121 | static inline void update_vsyscall(struct timekeeper *tk) | |
189374ae JS |
122 | { |
123 | } | |
124 | static inline void update_vsyscall_tz(void) | |
125 | { | |
126 | } | |
127 | #endif | |
128 | ||
d7b4202e | 129 | #endif /* _LINUX_TIMEKEEPER_INTERNAL_H */ |