lkml.org 
[lkml]   [2009]   [Jun]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH] sched: sched_clock() clocksource handling.
From
Date
On Tue, 2009-06-02 at 16:54 +0900, Paul Mundt wrote:
> unsigned long long __attribute__((weak)) sched_clock(void)
> {
> - return (unsigned long long)(jiffies - INITIAL_JIFFIES)
> - * (NSEC_PER_SEC / HZ);
> + unsigned long long time;
> + struct clocksource *clock;
> +
> + rcu_read_lock();
> + clock = rcu_dereference(sched_clocksource);
> + time = cyc2ns(clock, clocksource_read(clock));
> + rcu_read_unlock();
> +
> + return time;
> }

My concerns with the locking here still stand. Nothing you've said or
done bolsters the clocksource in modules argument. I think what your
planning for sh clocksources seems very inelegant. I would imagine a
better solution is out there. I'd prefer if you just leave sched_clock
alone.

Daniel



\
 
 \ /
  Last update: 2009-06-02 13:51    [W:0.101 / U:1.048 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site