diff options
author | John Stultz <john.stultz@linaro.org> | 2013-12-12 13:10:55 -0800 |
---|---|---|
committer | John Stultz <john.stultz@linaro.org> | 2013-12-23 11:54:32 -0800 |
commit | 47a1b796306356f358e515149d86baf0cc6bf007 (patch) | |
tree | 0ab5132f643db4318b395f2cb13f435ba3d9e5b6 /kernel/time/timekeeping.c | |
parent | 6fdda9a9c5db367130cf32df5d6618d08b89f46a (diff) | |
download | op-kernel-dev-47a1b796306356f358e515149d86baf0cc6bf007.zip op-kernel-dev-47a1b796306356f358e515149d86baf0cc6bf007.tar.gz |
tick/timekeeping: Call update_wall_time outside the jiffies lock
Since the xtime lock was split into the timekeeping lock and
the jiffies lock, we no longer need to call update_wall_time()
while holding the jiffies lock.
Thus, this patch splits update_wall_time() out from do_timer().
This allows us to get away from calling clock_was_set_delayed()
in update_wall_time() and instead use the standard clock_was_set()
call that previously would deadlock, as it causes the jiffies lock
to be acquired.
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Diffstat (limited to 'kernel/time/timekeeping.c')
-rw-r--r-- | kernel/time/timekeeping.c | 19 |
1 files changed, 4 insertions, 15 deletions
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index d62682b..44b7e6b 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -1360,7 +1360,7 @@ static inline void old_vsyscall_fixup(struct timekeeper *tk) * update_wall_time - Uses the current clocksource to increment the wall time * */ -static void update_wall_time(void) +void update_wall_time(void) { struct clocksource *clock; struct timekeeper *real_tk = &timekeeper; @@ -1441,19 +1441,8 @@ static void update_wall_time(void) write_seqcount_end(&timekeeper_seq); out: raw_spin_unlock_irqrestore(&timekeeper_lock, flags); - if (clock_was_set) { - /* - * XXX - I'd rather we just call clock_was_set(), but - * since we're currently holding the jiffies lock, calling - * clock_was_set would trigger an ipi which would then grab - * the jiffies lock and we'd deadlock. :( - * The right solution should probably be droping - * the jiffies lock before calling update_wall_time - * but that requires some rework of the tick sched - * code. - */ - clock_was_set_delayed(); - } + if (clock_set) + clock_was_set(); } /** @@ -1598,7 +1587,6 @@ struct timespec get_monotonic_coarse(void) void do_timer(unsigned long ticks) { jiffies_64 += ticks; - update_wall_time(); calc_global_load(ticks); } @@ -1756,4 +1744,5 @@ void xtime_update(unsigned long ticks) write_seqlock(&jiffies_lock); do_timer(ticks); write_sequnlock(&jiffies_lock); + update_wall_time(); } |