Re: [RFC PATCH] time: Fix truncation in jiffies_to_usecs()

[Frederic Weisbecker <fweisbec@gmail.com>]

On Mon, Apr 07, 2014 at 10:34:51PM -0700, Tony Luck wrote:
> On Mon, Apr 7, 2014 at 3:25 PM, Tony Luck <tony.luck@intel.com> wrote:
> 
> > c) If not this ... then what? Separate routine to convert large numbers
> >    of jiffies to usec/nsecs?  Should we make the existing one barf when
> >    handed a number that overflows?
> 
> Having thought about this a bit more - I'm leaning towards leaving
> jiffies_to_usecs() alone, but using it as a model for a from-scratch
> implementation of:
> u64 jiffies_to_nsecs(const unsigned long j)
> {
> }
> 
> This is what the uptime tracer actually needs - and there is only
> one user of jiffies_to_nsecs() to worry about.

I'm not sure I get what you're trying to do. We already have jiffies_to_nsecs().
Anyway I'll just wait and check out the next patch :)

Thanks.