Re: [PATCH] Provide u64 version of jiffies_to_usecs() in

Jonathan Lim
2008-02-19T21:59:15Z

On Tue Feb 19 13:25:25 2008, randy.dunlap@oracle.com wrote:
>
> > +u64 inline jiffies_64_to_usecs(const u64 j)
> > +{
> > + u64 tmp = j*HZ_TO_USEC_NUM + HZ_TO_USEC_DEN-1;
> > + do_div(tmp, HZ_TO_USEC_DEN);
>
> do_div() is:
> * The semantics of do_div() are:
> *
> * uint32_t do_div(uint64_t *n, uint32_t base)
>
> Maybe you want div64_64().
>
> > + return tmp;
> > +}
> > +EXPORT_SYMBOL(jiffies_64_to_usecs);
> > +

In include/asm-generic/div64.h, div64_64(uint64_t dividend, uint64_t divisor)
just returns (dividend / divisor). Isn't this the same as what I had before
in jiffies_64_to_usecs(), except that the arguments are of type u64?

Jonathan