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 clocksource_delta(u64 now,u64 last,u64 mask,u64 max_delta)18static inline u64 clocksource_delta(u64 now, u64 last, u64 mask, u64 max_delta) 19 { 20 u64 ret = (now - last) & mask; 21 22 /* 23 * Prevent time going backwards by checking the result against 24 * @max_delta. If greater, return 0. 25 */ 26 return ret > max_delta ? 0 : ret; 27 } 28 29 /* Semi public for serialization of non timekeeper VDSO updates. */ 30 extern raw_spinlock_t timekeeper_lock; 31 32 #endif /* _TIMEKEEPING_INTERNAL_H */ 33