1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _TIMEKEEPING_INTERNAL_H |
3 | #define _TIMEKEEPING_INTERNAL_H |
4 | |
5 | #include <linux/clocksource.h> |
6 | #include <linux/spinlock.h> |
7 | #include <linux/time.h> |
8 | |
9 | /* |
10 | * timekeeping debug functions |
11 | */ |
12 | #ifdef CONFIG_DEBUG_FS |
13 | extern void tk_debug_account_sleep_time(const struct timespec64 *t); |
14 | #else |
15 | #define tk_debug_account_sleep_time(x) |
16 | #endif |
17 | |
18 | #ifdef CONFIG_CLOCKSOURCE_VALIDATE_LAST_CYCLE |
19 | static inline u64 clocksource_delta(u64 now, u64 last, u64 mask) |
20 | { |
21 | u64 ret = (now - last) & mask; |
22 | |
23 | /* |
24 | * Prevent time going backwards by checking the MSB of mask in |
25 | * the result. If set, return 0. |
26 | */ |
27 | return ret & ~(mask >> 1) ? 0 : ret; |
28 | } |
29 | #else |
30 | static inline u64 clocksource_delta(u64 now, u64 last, u64 mask) |
31 | { |
32 | return (now - last) & mask; |
33 | } |
34 | #endif |
35 | |
36 | /* Semi public for serialization of non timekeeper VDSO updates. */ |
37 | extern raw_spinlock_t timekeeper_lock; |
38 | |
39 | #endif /* _TIMEKEEPING_INTERNAL_H */ |
40 | |