[patch 02/15] remove clocksource inline functions

From: Martin Schwidefsky
Date: Fri Aug 14 2009 - 09:49:23 EST


From: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>

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.

Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Daniel Walker <dwalker@xxxxxxxxxx>
Acked-by: John Stultz <johnstul@xxxxxxxxxx>
Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
---
include/linux/clocksource.h | 58 --------------------------------------------
kernel/time/timekeeping.c | 41 +++++++++++++++++++++----------
2 files changed, 28 insertions(+), 71 deletions(-)

Index: linux-2.6/kernel/time/timekeeping.c
===================================================================
--- linux-2.6.orig/kernel/time/timekeeping.c
+++ linux-2.6/kernel/time/timekeeping.c
@@ -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
}
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
Index: linux-2.6/include/linux/clocksource.h
===================================================================
--- linux-2.6.orig/include/linux/clocksource.h
+++ linux-2.6/include/linux/clocksource.h
@@ -268,64 +268,6 @@ static inline u32 clocksource_hz2mult(u3
}

/**
- * 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
* @cycles: Cycles

--
blue skies,
Martin.

"Reality continues to ruin my life." - Calvin.

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