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    SubjectRe: [RFC][PATCH 1/4] add jiffies_to_nsecs() helper and fix up size of usecs
    On 14.07.2005 [13:54:47 -0700], Dave Hansen wrote:
    > On Thu, 2005-07-14 at 13:28 -0700, Nishanth Aravamudan wrote:
    > > +static inline u64 jiffies_to_nsecs(const unsigned long j)
    > > +{
    > > +#if HZ <= NSEC_PER_SEC && !(NSEC_PER_SEC % HZ)
    > > + return (NSEC_PER_SEC / HZ) * (u64)j;
    > > +#elif HZ > NSEC_PER_SEC && !(HZ % NSEC_PER_SEC)
    > > + return ((u64)j + (HZ / NSEC_PER_SEC) - 1)/(HZ / NSEC_PER_SEC);
    > > +#else
    > > + return ((u64)j * NSEC_PER_SEC) / HZ;
    > > +#endif
    > > +}
    >
    > That might look a little better something like:
    >
    > static inline u64 jiffies_to_nsecs(const unsigned long __j)
    > {
    > u64 j = __j;
    >
    > if (HZ <= NSEC_PER_SEC && !(NSEC_PER_SEC % HZ))
    > return (NSEC_PER_SEC / HZ) * j;
    > else if (HZ > NSEC_PER_SEC && !(HZ % NSEC_PER_SEC))
    > return (j + (HZ / NSEC_PER_SEC) - 1)/(HZ / NSEC_PER_SEC);
    > else
    > return (j * NSEC_PER_SEC) / HZ;
    > }
    >
    > Compilers are smart :)

    Well, I was trying to keep it similar to the other conversion functions.
    I guess the compiler can evaluate the conditional full of constants at
    compile-time regardless of whether it is #if or if ().

    I can make these changes if others would like them as well.

    Thanks,
    Nish
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