kernel/time/timekeeping_internal.h

   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
  14 DECLARE_PER_CPU(unsigned long, timekeeping_mg_floor_swaps);
  15
  16 static inline void timekeeping_inc_mg_floor_swaps(void)
  17 {
  18         this_cpu_inc(timekeeping_mg_floor_swaps);
  19 }
  20
  21 extern void tk_debug_account_sleep_time(const struct timespec64 *t);
  22
  23 #else
  24
  25 #define tk_debug_account_sleep_time(x)
  26
  27 static inline void timekeeping_inc_mg_floor_swaps(void)
  28 {
  29 }
  30
  31 #endif
  32
  33 static inline u64 clocksource_delta(u64 now, u64 last, u64 mask)
  34 {
  35         u64 ret = (now - last) & mask;
  36
  37         /*
  38          * Prevent time going backwards by checking the MSB of mask in
  39          * the result. If set, return 0.
  40          */
  41         return ret & ~(mask >> 1) ? 0 : ret;
  42 }
  43
  44 /* Semi public for serialization of non timekeeper VDSO updates. */
  45 unsigned long timekeeper_lock_irqsave(void);
  46 void timekeeper_unlock_irqrestore(unsigned long flags);
  47
  48 #endif /* _TIMEKEEPING_INTERNAL_H */