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timekeeping: Remove clocksource inline functions
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The three inline functions clocksource_read, clocksource_enable and
clocksource_disable are simple wrappers of an indirect call plus the
copy from and to the mult_orig value. The functions are exclusively
used by the timekeeping code which has intimate knowledge of the
clocksource anyway. Therefore remove the inline functions. No
functional change.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: John Stultz <johnstul@us.ibm.com>
Cc: Daniel Walker <dwalker@fifo99.com>
LKML-Reference: <20090814134807.903108946@de.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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Martin Schwidefsky authored and Thomas Gleixner committed Aug 15, 2009
1 parent 31089c1 commit a0f7d48
Showing 2 changed files with 28 additions and 71 deletions.
58 changes: 0 additions & 58 deletions include/linux/clocksource.h
Original file line number Diff line number Diff line change
@@ -267,64 +267,6 @@ static inline u32 clocksource_hz2mult(u32 hz, u32 shift_constant)
return (u32)tmp;
}

/**
* clocksource_read: - Access the clocksource's current cycle value
* @cs: pointer to clocksource being read
*
* Uses the clocksource to return the current cycle_t value
*/
static inline cycle_t clocksource_read(struct clocksource *cs)
{
return cs->read(cs);
}

/**
* clocksource_enable: - enable clocksource
* @cs: pointer to clocksource
*
* Enables the specified clocksource. The clocksource callback
* function should start up the hardware and setup mult and field
* members of struct clocksource to reflect hardware capabilities.
*/
static inline int clocksource_enable(struct clocksource *cs)
{
int ret = 0;

if (cs->enable)
ret = cs->enable(cs);

/*
* The frequency may have changed while the clocksource
* was disabled. If so the code in ->enable() must update
* the mult value to reflect the new frequency. Make sure
* mult_orig follows this change.
*/
cs->mult_orig = cs->mult;

return ret;
}

/**
* clocksource_disable: - disable clocksource
* @cs: pointer to clocksource
*
* Disables the specified clocksource. The clocksource callback
* function should power down the now unused hardware block to
* save power.
*/
static inline void clocksource_disable(struct clocksource *cs)
{
/*
* Save mult_orig in mult so clocksource_enable() can
* restore the value regardless if ->enable() updates
* the value of mult or not.
*/
cs->mult = cs->mult_orig;

if (cs->disable)
cs->disable(cs);
}

/**
* cyc2ns - converts clocksource cycles to nanoseconds
* @cs: Pointer to clocksource
41 changes: 28 additions & 13 deletions kernel/time/timekeeping.c
Original file line number Diff line number Diff line change
@@ -79,7 +79,7 @@ static void clocksource_forward_now(void)
cycle_t cycle_now, cycle_delta;
s64 nsec;

cycle_now = clocksource_read(clock);
cycle_now = clock->read(clock);
cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
clock->cycle_last = cycle_now;

@@ -114,7 +114,7 @@ void getnstimeofday(struct timespec *ts)
*ts = xtime;

/* read clocksource: */
cycle_now = clocksource_read(clock);
cycle_now = clock->read(clock);

/* calculate the delta since the last update_wall_time: */
cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
@@ -146,7 +146,7 @@ ktime_t ktime_get(void)
nsecs = xtime.tv_nsec + wall_to_monotonic.tv_nsec;

/* read clocksource: */
cycle_now = clocksource_read(clock);
cycle_now = clock->read(clock);

/* calculate the delta since the last update_wall_time: */
cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
@@ -186,7 +186,7 @@ void ktime_get_ts(struct timespec *ts)
tomono = wall_to_monotonic;

/* read clocksource: */
cycle_now = clocksource_read(clock);
cycle_now = clock->read(clock);

/* calculate the delta since the last update_wall_time: */
cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
@@ -274,16 +274,29 @@ static void change_clocksource(void)

clocksource_forward_now();

if (clocksource_enable(new))
if (new->enable && !new->enable(new))
return;
/*
* The frequency may have changed while the clocksource
* was disabled. If so the code in ->enable() must update
* the mult value to reflect the new frequency. Make sure
* mult_orig follows this change.
*/
new->mult_orig = new->mult;

new->raw_time = clock->raw_time;
old = clock;
clock = new;
clocksource_disable(old);
/*
* Save mult_orig in mult so that the value can be restored
* regardless if ->enable() updates the value of mult or not.
*/
old->mult = old->mult_orig;
if (old->disable)
old->disable(old);

clock->cycle_last = 0;
clock->cycle_last = clocksource_read(clock);
clock->cycle_last = clock->read(clock);
clock->error = 0;
clock->xtime_nsec = 0;
clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH);
@@ -373,7 +386,7 @@ void getrawmonotonic(struct timespec *ts)
seq = read_seqbegin(&xtime_lock);

/* read clocksource: */
cycle_now = clocksource_read(clock);
cycle_now = clock->read(clock);

/* calculate the delta since the last update_wall_time: */
cycle_delta = (cycle_now - clock->cycle_last) & clock->mask;
@@ -435,9 +448,12 @@ void __init timekeeping_init(void)
ntp_init();

clock = clocksource_get_next();
clocksource_enable(clock);
if (clock->enable)
clock->enable(clock);
/* set mult_orig on enable */
clock->mult_orig = clock->mult;
clocksource_calculate_interval(clock, NTP_INTERVAL_LENGTH);
clock->cycle_last = clocksource_read(clock);
clock->cycle_last = clock->read(clock);

xtime.tv_sec = sec;
xtime.tv_nsec = 0;
@@ -477,8 +493,7 @@ static int timekeeping_resume(struct sys_device *dev)
}
update_xtime_cache(0);
/* re-base the last cycle value */
clock->cycle_last = 0;
clock->cycle_last = clocksource_read(clock);
clock->cycle_last = clock->read(clock);
clock->error = 0;
timekeeping_suspended = 0;
write_sequnlock_irqrestore(&xtime_lock, flags);
@@ -630,7 +645,7 @@ void update_wall_time(void)
return;

#ifdef CONFIG_GENERIC_TIME
offset = (clocksource_read(clock) - clock->cycle_last) & clock->mask;
offset = (clock->read(clock) - clock->cycle_last) & clock->mask;
#else
offset = clock->cycle_interval;
#endif

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