time: Remove most of xtime_lock usage in timekeeping.c

Now that ntp.c's locking is reworked, we can remove most
of the xtime_lock usage in timekeeping.c

The remaining xtime_lock presence is really for jiffies access
and the global load calculation.

CC: Thomas Gleixner <tglx@linutronix.de>
CC: Eric Dumazet <eric.dumazet@gmail.com>
CC: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
This commit is contained in:
John Stultz 2011-11-14 14:05:44 -08:00
parent bd3312681f
commit 92c1d3ed4d

View File

@ -172,7 +172,6 @@ static inline s64 timekeeping_get_ns_raw(void)
return clocksource_cyc2ns(cycle_delta, clock->mult, clock->shift);
}
/* must hold xtime_lock */
void timekeeping_leap_insert(int leapsecond)
{
unsigned long flags;
@ -372,13 +371,12 @@ EXPORT_SYMBOL(do_gettimeofday);
int do_settimeofday(const struct timespec *tv)
{
struct timespec ts_delta;
unsigned long flags1,flags2;
unsigned long flags;
if ((unsigned long)tv->tv_nsec >= NSEC_PER_SEC)
return -EINVAL;
write_seqlock_irqsave(&xtime_lock, flags1);
write_seqlock_irqsave(&timekeeper.lock, flags2);
write_seqlock_irqsave(&timekeeper.lock, flags);
timekeeping_forward_now();
@ -395,8 +393,7 @@ int do_settimeofday(const struct timespec *tv)
update_vsyscall(&timekeeper.xtime, &timekeeper.wall_to_monotonic,
timekeeper.clock, timekeeper.mult);
write_sequnlock_irqrestore(&timekeeper.lock, flags2);
write_sequnlock_irqrestore(&xtime_lock, flags1);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
/* signal hrtimers about time change */
clock_was_set();
@ -415,13 +412,12 @@ EXPORT_SYMBOL(do_settimeofday);
*/
int timekeeping_inject_offset(struct timespec *ts)
{
unsigned long flags1,flags2;
unsigned long flags;
if ((unsigned long)ts->tv_nsec >= NSEC_PER_SEC)
return -EINVAL;
write_seqlock_irqsave(&xtime_lock, flags1);
write_seqlock_irqsave(&timekeeper.lock, flags2);
write_seqlock_irqsave(&timekeeper.lock, flags);
timekeeping_forward_now();
@ -435,8 +431,7 @@ int timekeeping_inject_offset(struct timespec *ts)
update_vsyscall(&timekeeper.xtime, &timekeeper.wall_to_monotonic,
timekeeper.clock, timekeeper.mult);
write_sequnlock_irqrestore(&timekeeper.lock, flags2);
write_sequnlock_irqrestore(&xtime_lock, flags1);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
/* signal hrtimers about time change */
clock_was_set();
@ -598,9 +593,7 @@ void __init timekeeping_init(void)
seqlock_init(&timekeeper.lock);
write_seqlock_irqsave(&xtime_lock, flags);
ntp_init();
write_sequnlock_irqrestore(&xtime_lock, flags);
write_seqlock_irqsave(&timekeeper.lock, flags);
clock = clocksource_default_clock();
@ -661,7 +654,7 @@ static void __timekeeping_inject_sleeptime(struct timespec *delta)
*/
void timekeeping_inject_sleeptime(struct timespec *delta)
{
unsigned long flags1,flags2;
unsigned long flags;
struct timespec ts;
/* Make sure we don't set the clock twice */
@ -669,8 +662,7 @@ void timekeeping_inject_sleeptime(struct timespec *delta)
if (!(ts.tv_sec == 0 && ts.tv_nsec == 0))
return;
write_seqlock_irqsave(&xtime_lock, flags1);
write_seqlock_irqsave(&timekeeper.lock, flags2);
write_seqlock_irqsave(&timekeeper.lock, flags);
timekeeping_forward_now();
@ -681,8 +673,7 @@ void timekeeping_inject_sleeptime(struct timespec *delta)
update_vsyscall(&timekeeper.xtime, &timekeeper.wall_to_monotonic,
timekeeper.clock, timekeeper.mult);
write_sequnlock_irqrestore(&timekeeper.lock, flags2);
write_sequnlock_irqrestore(&xtime_lock, flags1);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
/* signal hrtimers about time change */
clock_was_set();
@ -698,15 +689,14 @@ void timekeeping_inject_sleeptime(struct timespec *delta)
*/
static void timekeeping_resume(void)
{
unsigned long flags1,flags2;
unsigned long flags;
struct timespec ts;
read_persistent_clock(&ts);
clocksource_resume();
write_seqlock_irqsave(&xtime_lock, flags1);
write_seqlock_irqsave(&timekeeper.lock, flags2);
write_seqlock_irqsave(&timekeeper.lock, flags);
if (timespec_compare(&ts, &timekeeping_suspend_time) > 0) {
ts = timespec_sub(ts, timekeeping_suspend_time);
@ -716,8 +706,7 @@ static void timekeeping_resume(void)
timekeeper.clock->cycle_last = timekeeper.clock->read(timekeeper.clock);
timekeeper.ntp_error = 0;
timekeeping_suspended = 0;
write_sequnlock_irqrestore(&timekeeper.lock, flags2);
write_sequnlock_irqrestore(&xtime_lock, flags1);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
touch_softlockup_watchdog();
@ -729,14 +718,13 @@ static void timekeeping_resume(void)
static int timekeeping_suspend(void)
{
unsigned long flags1,flags2;
unsigned long flags;
struct timespec delta, delta_delta;
static struct timespec old_delta;
read_persistent_clock(&timekeeping_suspend_time);
write_seqlock_irqsave(&xtime_lock, flags1);
write_seqlock_irqsave(&timekeeper.lock, flags2);
write_seqlock_irqsave(&timekeeper.lock, flags);
timekeeping_forward_now();
timekeeping_suspended = 1;
@ -759,8 +747,7 @@ static int timekeeping_suspend(void)
timekeeping_suspend_time =
timespec_add(timekeeping_suspend_time, delta_delta);
}
write_sequnlock_irqrestore(&timekeeper.lock, flags2);
write_sequnlock_irqrestore(&xtime_lock, flags1);
write_sequnlock_irqrestore(&timekeeper.lock, flags);
clockevents_notify(CLOCK_EVT_NOTIFY_SUSPEND, NULL);
clocksource_suspend();
@ -1006,7 +993,6 @@ static cycle_t logarithmic_accumulation(cycle_t offset, int shift)
/**
* update_wall_time - Uses the current clocksource to increment the wall time
*
* Called from the timer interrupt, must hold a write on xtime_lock.
*/
static void update_wall_time(void)
{