For implementing a shadow timekeeper and a split calculation/update region we need to store the cycle_last value in the timekeeper and update the value in the clocksource struct only in the update region. Add the extra storage to the timekeeper. Signed-off-by: Thomas Gleixner --- include/linux/timekeeper_internal.h | 2 ++ kernel/time/timekeeping.c | 4 ++-- 2 files changed, 4 insertions(+), 2 deletions(-) Index: linux-2.6/include/linux/timekeeper_internal.h =================================================================== --- linux-2.6.orig/include/linux/timekeeper_internal.h +++ linux-2.6/include/linux/timekeeper_internal.h @@ -20,6 +20,8 @@ struct timekeeper { u32 shift; /* Number of clock cycles in one NTP interval. */ cycle_t cycle_interval; + /* Last cycle value (also stored in clock->cycle_last) */ + cycle_t cycle_last; /* Number of clock shifted nano seconds in one NTP interval. */ u64 xtime_interval; /* shifted nano seconds left over when rounding cycle_interval */ Index: linux-2.6/kernel/time/timekeeping.c =================================================================== --- linux-2.6.orig/kernel/time/timekeeping.c +++ linux-2.6/kernel/time/timekeeping.c @@ -99,7 +99,7 @@ static void tk_setup_internals(struct ti old_clock = tk->clock; tk->clock = clock; - clock->cycle_last = clock->read(clock); + tk->cycle_last = clock->cycle_last = clock->read(clock); /* Do the ns -> cycle conversion first, using original mult */ tmp = NTP_INTERVAL_LENGTH; @@ -250,7 +250,7 @@ static void timekeeping_forward_now(stru clock = tk->clock; cycle_now = clock->read(clock); cycle_delta = (cycle_now - clock->cycle_last) & clock->mask; - clock->cycle_last = cycle_now; + tk->cycle_last = clock->cycle_last = cycle_now; tk->xtime_nsec += cycle_delta * tk->mult; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/