[POWERPC] spusched: Fix timeslice calculations

The current timeslice code mixes 'jiffies' up with 'spesched ticks'. This
change correctly defines the number of time slices each SPE contexts is
given, and clarifies the comment.

This brings the default timeslice for SPE contexts into a reasonable
range.

Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This commit is contained in:
Jeremy Kerr 2007-06-29 10:57:53 +10:00 committed by Paul Mackerras
parent fe443ef2ac
commit 60e2423933

View file

@ -70,11 +70,11 @@ static struct timer_list spusched_timer;
/*
* These are the 'tuning knobs' of the scheduler:
*
* Minimum timeslice is 5 msecs (or 10 jiffies, whichever is larger),
* default timeslice is 100 msecs, maximum timeslice is 800 msecs.
* Minimum timeslice is 5 msecs (or 1 spu scheduler tick, whichever is
* larger), default timeslice is 100 msecs, maximum timeslice is 800 msecs.
*/
#define MIN_SPU_TIMESLICE max(5 * HZ / 100, 10)
#define DEF_SPU_TIMESLICE (100 * HZ / 100)
#define MIN_SPU_TIMESLICE max(5 * HZ / (1000 * SPUSCHED_TICK), 1)
#define DEF_SPU_TIMESLICE (100 * HZ / (1000 * SPUSCHED_TICK))
#define MAX_USER_PRIO (MAX_PRIO - MAX_RT_PRIO)
#define SCALE_PRIO(x, prio) \