diff options
| -rw-r--r-- | kernel/time/timekeeping.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 10c6e37dc0dc..b6ac7847bc0a 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -2765,9 +2765,53 @@ static int aux_get_timespec(clockid_t id, struct timespec64 *tp) return ktime_get_aux_ts64(id, tp) ? 0 : -ENODEV; } +static int aux_clock_set(const clockid_t id, const struct timespec64 *tnew) +{ + struct tk_data *aux_tkd = aux_get_tk_data(id); + struct timekeeper *aux_tks; + ktime_t tnow, nsecs; + + if (!timespec64_valid_settod(tnew)) + return -EINVAL; + if (!aux_tkd) + return -ENODEV; + + aux_tks = &aux_tkd->shadow_timekeeper; + + guard(raw_spinlock_irq)(&aux_tkd->lock); + if (!aux_tks->clock_valid) + return -ENODEV; + + /* Forward the timekeeper base time */ + timekeeping_forward_now(aux_tks); + /* + * Get the updated base time. tkr_mono.base has not been + * updated yet, so do that first. That makes the update + * in timekeeping_update_from_shadow() redundant, but + * that's harmless. After that @tnow can be calculated + * by using tkr_mono::cycle_last, which has been set + * by timekeeping_forward_now(). + */ + tk_update_ktime_data(aux_tks); + nsecs = timekeeping_cycles_to_ns(&aux_tks->tkr_mono, aux_tks->tkr_mono.cycle_last); + tnow = ktime_add(aux_tks->tkr_mono.base, nsecs); + + /* + * Calculate the new AUX offset as delta to @tnow ("monotonic"). + * That avoids all the tk::xtime back and forth conversions as + * xtime ("realtime") is not applicable for auxiliary clocks and + * kept in sync with "monotonic". + */ + aux_tks->offs_aux = ktime_sub(timespec64_to_ktime(*tnew), tnow); + + timekeeping_update_from_shadow(aux_tkd, TK_UPDATE_ALL); + return 0; +} + const struct k_clock clock_aux = { .clock_getres = aux_get_res, .clock_get_timespec = aux_get_timespec, + .clock_set = aux_clock_set, }; static __init void tk_aux_setup(void) |