Commit 2c8aea59 authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

timekeeping: Add auxiliary clock support to __timekeeping_inject_offset() 



Redirect the relative offset adjustment to the auxiliary clock offset
instead of modifying CLOCK_REALTIME, which has no meaning in context of
these clocks.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Acked-by: default avatarJohn Stultz <jstultz@google.com>
Link: https://lore.kernel.org/all/20250625183758.124057787@linutronix.de
parent e8db3a55

kernel/time/timekeeping.c

+31 −8
Original line number Diff line number Diff line
@@ -1431,6 +1431,11 @@ int do_settimeofday64(const struct timespec64 *ts) 
}

EXPORT_SYMBOL(do_settimeofday64);



static inline bool timekeeper_is_core_tk(struct timekeeper *tk)

{

	return !IS_ENABLED(CONFIG_POSIX_AUX_CLOCKS) || tk->id == TIMEKEEPER_CORE;

}



/**

 * __timekeeping_inject_offset - Adds or subtracts from the current time.

 * @tkd:	Pointer to the timekeeper to modify
@@ -1448,6 +1453,7 @@ static int __timekeeping_inject_offset(struct tk_data *tkd, const struct timespe 


	timekeeping_forward_now(tks);



	if (timekeeper_is_core_tk(tks)) {

		/* Make sure the proposed value is valid */

		tmp = timespec64_add(tk_xtime(tks), *ts);

		if (timespec64_compare(&tks->wall_to_monotonic, ts) > 0 ||
@@ -1458,6 +1464,23 @@ static int __timekeeping_inject_offset(struct tk_data *tkd, const struct timespe 


		tk_xtime_add(tks, ts);

		tk_set_wall_to_mono(tks, timespec64_sub(tks->wall_to_monotonic, *ts));

	} else {

		struct tk_read_base *tkr_mono = &tks->tkr_mono;

		ktime_t now, offs;



		/* Get the current time */

		now = ktime_add_ns(tkr_mono->base, timekeeping_get_ns(tkr_mono));

		/* Add the relative offset change */

		offs = ktime_add(tks->offs_aux, timespec64_to_ktime(*ts));



		/* Prevent that the resulting time becomes negative */

		if (ktime_add(now, offs) < 0) {

			timekeeping_restore_shadow(tkd);

			return -EINVAL;

		}

		tks->offs_aux = offs;

	}



	timekeeping_update_from_shadow(tkd, TK_UPDATE_ALL);

	return 0;

}