Re: [PATCH] timekeeping fix mismerge

[Andrew Morton <akpm@linux-foundation.org>]

On Mon, 14 May 2007 11:10:02 +0200
Thomas Gleixner <tglx@linutronix.de> wrote:

> The time keeping code move to kernel/time/timekeeping.c broke the
> clocksource resume logic patch. Fix it up and move the
> clocksource_resume() call to the appropriate place.
> 
> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
> 
> diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
> diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
> index f9217bf..3d1042f 100644
> --- a/kernel/time/timekeeping.c
> +++ b/kernel/time/timekeeping.c
> @@ -273,6 +273,8 @@ static int timekeeping_resume(struct sys_device *dev)
>  	unsigned long flags;
>  	unsigned long now = read_persistent_clock();
>  
> +	clocksource_resume();
> +
>  	write_seqlock_irqsave(&xtime_lock, flags);
>  
>  	if (now && (now > timekeeping_suspend_time)) {
> diff --git a/kernel/timer.c b/kernel/timer.c
> index a6c580a..5ec5490 100644
> --- a/kernel/timer.c
> +++ b/kernel/timer.c
> @@ -1499,8 +1499,6 @@ unregister_time_interpolator(struct time_interpolator *ti)
>  		prev = &curr->next;
>  	}
>  
> -	clocksource_resume();
> -
>  	write_seqlock_irqsave(&xtime_lock, flags);
>  	if (ti == time_interpolator) {
>  		/* we lost the best time-interpolator: */
> 

Urgh, that was probably me trying to manage the maelstrom from a million
monkeys mucking in the same code for multiple months, sigh.

So what do "broke" and "fix" mean in this context?  What are the
consequences of this bug, and of its fix?  Is the above appropriate for
2.6.21.x and if so why?

Thanks.