@@ -585,15 +585,19 @@ static void timekeeping_update(struct timekeeper *tk, unsigned int action)
update_vsyscall(tk);
update_pvclock_gtod(tk, action & TK_CLOCK_WAS_SET);
- if (action & TK_MIRROR)
- memcpy(&shadow_timekeeper, &tk_core.timekeeper,
- sizeof(tk_core.timekeeper));
-
update_fast_timekeeper(&tk->tkr_mono, &tk_fast_mono);
update_fast_timekeeper(&tk->tkr_raw, &tk_fast_raw);
if (action & TK_CLOCK_WAS_SET)
tk->clock_was_set_seq++;
+ /*
+ * The mirroring of the data to the shadow-timekeeper needs
+ * to happen last here to ensure we don't over-write the
+ * timekeeper structure on the next update with stale data
+ */
+ if (action & TK_MIRROR)
+ memcpy(&shadow_timekeeper, &tk_core.timekeeper,
+ sizeof(tk_core.timekeeper));
}
/**
It was reported that 868a3e915f7f5eba (hrtimer: Make offset update smarter) was causing timer problems after suspend/resume. The problem with that change is the modification to clock_was_set_seq in timekeeping_update is done prior to mirroring the time state to the shadow-timekeeper. Thus the next time we do update_wall_time() the updated sequence is overwritten by whats in the shadow copy. This patch moves the shadow-timekeeper mirroring to the end of the function, after all updates have been made, so all data is kept in sync. (This patch also affects the update_fast_timekeeper calls which were also problematically done prior to the mirroring). Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@kernel.org> Reported-by: Jeremiah Mahler <jmmahler@gmail.com> Signed-off-by: John Stultz <john.stultz@linaro.org> --- kernel/time/timekeeping.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)