Re: [RFC][patch 02/12] remove clocksource inline functions

[john stultz <johnstul@us.ibm.com>]

On Wed, 2009-07-29 at 15:41 +0200, Martin Schwidefsky wrote:
> plain text document attachment (clocksource-inline.diff)
> From: Martin Schwidefsky <schwidefsky@de.ibm.com>
> 
> Remove clocksource_read, clocksource_enable and clocksource_disable
> inline functions. No functional change.
> 
> Cc: Ingo Molnar <mingo@elte.hu>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: john stultz <johnstul@us.ibm.com>
> Cc: Daniel Walker <dwalker@fifo99.com>
> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

Again, Magnus's fix for mult_orig that Thomas has (or *should* have)
queued at this point for 2.6.31 will collide with this, but the fix is
trivial.

Acked-by: John Stultz <johnstul@us.ibm.com>


> ---
>  include/linux/clocksource.h |   46 --------------------------------------------
>  kernel/time/timekeeping.c   |   32 +++++++++++++++++-------------
>  2 files changed, 18 insertions(+), 60 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 +274,18 @@ static void change_clocksource(void)
> 
>  	clocksource_forward_now();
> 
> -	if (clocksource_enable(new))
> +	if (new->enable && ! new->enable(new))
>  		return;
> +	/* save mult_orig on enable */
> +	new->mult_orig = new->mult;
> 
>  	new->raw_time = clock->raw_time;
>  	old = clock;
>  	clock = new;
> -	clocksource_disable(old);
> +	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 +375,7 @@ 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 +437,12 @@ void __init timekeeping_init(void)
>  	ntp_init();
> 
>  	clock = clocksource_get_next();
> -	clocksource_enable(clock);
> +	if (clock->enable)
> +		clock->enable(clock);
> +	/* save 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 +482,7 @@ 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 +634,7 @@ 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
> @@ -268,52 +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);
> -
> -	/* save mult_orig on enable */
> -	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)
> -{
> -	if (cs->disable)
> -		cs->disable(cs);
> -}
> -
> -/**
>   * cyc2ns - converts clocksource cycles to nanoseconds
>   * @cs:		Pointer to clocksource
>   * @cycles:	Cycles
>