HZ never goes much further 1000 and a bit. And if we ever reach one tick per microsecond, we might be having a problem.
Lets stop maintaining this special case, just leave a paranoid check. Cc: Christoph Lameter <[email protected]> Cc: Ingo Molnar <[email protected]> Cc; John Stultz <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Preeti U Murthy <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Viresh Kumar <[email protected]> Signed-off-by: Frederic Weisbecker <[email protected]> --- kernel/time/time.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/kernel/time/time.c b/kernel/time/time.c index 972e3bb..6a22980 100644 --- a/kernel/time/time.c +++ b/kernel/time/time.c @@ -268,10 +268,14 @@ EXPORT_SYMBOL(jiffies_to_msecs); unsigned int jiffies_to_usecs(const unsigned long j) { -#if HZ <= USEC_PER_SEC && !(USEC_PER_SEC % HZ) + /* + * Hz usually doesn't go much further MSEC_PER_SEC. + * jiffies_to_usecs() and usecs_to_jiffies() depend on that. + */ + BUILD_BUG_ON(HZ > USEC_PER_SEC); + +#if !(USEC_PER_SEC % HZ) return (USEC_PER_SEC / HZ) * j; -#elif HZ > USEC_PER_SEC && !(HZ % USEC_PER_SEC) - return (j + (HZ / USEC_PER_SEC) - 1)/(HZ / USEC_PER_SEC); #else # if BITS_PER_LONG == 32 return (HZ_TO_USEC_MUL32 * j) >> HZ_TO_USEC_SHR32; @@ -526,10 +530,8 @@ unsigned long usecs_to_jiffies(const unsigned int u) { if (u > jiffies_to_usecs(MAX_JIFFY_OFFSET)) return MAX_JIFFY_OFFSET; -#if HZ <= USEC_PER_SEC && !(USEC_PER_SEC % HZ) +#if !(USEC_PER_SEC % HZ) return (u + (USEC_PER_SEC / HZ) - 1) / (USEC_PER_SEC / HZ); -#elif HZ > USEC_PER_SEC && !(HZ % USEC_PER_SEC) - return u * (HZ / USEC_PER_SEC); #else return (USEC_TO_HZ_MUL32 * u + USEC_TO_HZ_ADJ32) >> USEC_TO_HZ_SHR32; -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
