The comment and the actual macros are inconsistent.
positive number * (19-n) is a decreasing function of n!
+ * The higher a process's priority, the bigger timeslices
+ * it gets during one round of execution. But even the lowest
+ * priority process gets MIN_TIMESLICE worth of execution time.
+ */
-#define NICE_TO_TIMESLICE(n) (MIN_TIMESLICE + \
- ((MAX_TIMESLICE - MIN_TIMESLICE) * (19 - (n))) / 39)
+#define NICE_TO_TIMESLICE(n) (MIN_TIMESLICE + \
+ ((MAX_TIMESLICE - MIN_TIMESLICE) * (19-(n))) / 39)
I still suggest a different set as faster and more readable at least to
me. Just two operations instead of 4!
#define NICE_TO_TIMESLICE(n) (((n)+21)*(HZ/10)) // should be positive!
#define MAX_TIMESLICE NICE_TO_TIMESLICE(19)
#define MIN_TIMESLICE NICE_TO_TIMESLICE(-20)
with later tweaking done in the function, like (((n)+22)*(HZ/25)) instead.
Alexei
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