Re: boot time, process start time, and NOW time

[Tim Schmielau]

> > Where did this all end up?  Complaints about wandering start times are
> > persistent, and it'd be nice to get some fix in place...
[...]

> Simple fix: revert the patch below.
> Complicated fix: correct process start times in fork.c (no patch provided, 
> too complicated for me to do).

Well, if we actually revert the patch, we'd also need to revert the 
changes made to jiffies_to_clock_t() & Co. in response to the patch.
Otherwise we again end up inconsistent.

I could make a patch for that tomorrow, if there's interest. At least to 
show that my analysis actually is correct.

Alternatively we might formulate uptime in terms of jiffies_to_clock_t()). 


Tim



> diff -Nru a/fs/proc/proc_misc.c b/fs/proc/proc_misc.c
> --- a/fs/proc/proc_misc.c	2004-08-16 15:48:44 -07:00
> +++ b/fs/proc/proc_misc.c	2004-08-16 15:48:44 -07:00
> @@ -137,36 +137,19 @@
>  static int uptime_read_proc(char *page, char **start, off_t off,
>  				 int count, int *eof, void *data)
>  {
> -	u64 uptime;
> -	unsigned long uptime_remainder;
> +	struct timespec uptime;
> +	struct timespec idle;
>  	int len;
> +	u64 idle_jiffies = init_task.utime + init_task.stime;
>  
> -	uptime = get_jiffies_64() - INITIAL_JIFFIES;
> -	uptime_remainder = (unsigned long) do_div(uptime, HZ);
> +	do_posix_clock_monotonic_gettime(&uptime);
> +	jiffies_to_timespec(idle_jiffies, &idle);
> +	len = sprintf(page,"%lu.%02lu %lu.%02lu\n",
> +			(unsigned long) uptime.tv_sec,
> +			(uptime.tv_nsec / (NSEC_PER_SEC / 100)),
> +			(unsigned long) idle.tv_sec,
> +			(idle.tv_nsec / (NSEC_PER_SEC / 100)));
>  
> -#if HZ!=100
> -	{
> -		u64 idle = init_task.utime + init_task.stime;
> -		unsigned long idle_remainder;
> -
> -		idle_remainder = (unsigned long) do_div(idle, HZ);
> -		len = sprintf(page,"%lu.%02lu %lu.%02lu\n",
> -			(unsigned long) uptime,
> -			(uptime_remainder * 100) / HZ,
> -			(unsigned long) idle,
> -			(idle_remainder * 100) / HZ);
> -	}
> -#else
> -	{
> -		unsigned long idle = init_task.utime + init_task.stime;
> -
> -		len = sprintf(page,"%lu.%02lu %lu.%02lu\n",
> -			(unsigned long) uptime,
> -			uptime_remainder,
> -			idle / HZ,
> -			idle % HZ);
> -	}
> -#endif
>  	return proc_calc_metrics(page, start, off, count, eof, len);
>  }
> 
> 

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/