Messages in this thread Patch in this message | | | From | Con Kolivas <> | Subject | Re: [PATCH] sched: activate SCHED BATCH expired | Date | Sat, 18 Mar 2006 01:11:00 +1100 |
| |
On Saturday 18 March 2006 00:46, Nick Piggin wrote: > I guess it isn't doing the cmov because it doesn't want to do the > extra load in the common case, which is fair enough (are you compiling > for a pentiumpro+, without generic x86 support?
For pentium4 with no generic support.
> what about if you > turn off optimise for size?)
Dunno, sleep is taking me...
> At least other archtectures might be able to make better use of it, > and I agree even for i386 the code looks better (and slightly smaller).
Good enough for me. Here's a respin, thanks!
Cheers, Con --- To increase the strength of SCHED_BATCH as a scheduling hint we can activate batch tasks on the expired array since by definition they are latency insensitive tasks.
Signed-off-by: Con Kolivas <kernel@kolivas.org>
--- include/linux/sched.h | 1 + kernel/sched.c | 10 +++++++--- 2 files changed, 8 insertions(+), 3 deletions(-)
Index: linux-2.6.16-rc6-mm1/include/linux/sched.h =================================================================== --- linux-2.6.16-rc6-mm1.orig/include/linux/sched.h 2006-03-13 20:12:22.000000000 +1100 +++ linux-2.6.16-rc6-mm1/include/linux/sched.h 2006-03-17 23:08:31.000000000 +1100 @@ -485,6 +485,7 @@ struct signal_struct { #define MAX_PRIO (MAX_RT_PRIO + 40) #define rt_task(p) (unlikely((p)->prio < MAX_RT_PRIO)) +#define batch_task(p) (unlikely((p)->policy == SCHED_BATCH)) /* * Some day this will be a full-fledged user tracking system.. Index: linux-2.6.16-rc6-mm1/kernel/sched.c =================================================================== --- linux-2.6.16-rc6-mm1.orig/kernel/sched.c 2006-03-13 20:12:15.000000000 +1100 +++ linux-2.6.16-rc6-mm1/kernel/sched.c 2006-03-18 01:05:02.000000000 +1100 @@ -737,9 +737,13 @@ static inline void dec_nr_running(task_t /* * __activate_task - move a task to the runqueue. */ -static inline void __activate_task(task_t *p, runqueue_t *rq) +static void __activate_task(task_t *p, runqueue_t *rq) { - enqueue_task(p, rq->active); + prio_array_t *target = rq->active; + + if (batch_task(p)) + target = rq->expired; + enqueue_task(p, target); inc_nr_running(p, rq); } @@ -758,7 +762,7 @@ static int recalc_task_prio(task_t *p, u unsigned long long __sleep_time = now - p->timestamp; unsigned long sleep_time; - if (unlikely(p->policy == SCHED_BATCH)) + if (batch_task(p)) sleep_time = 0; else { if (__sleep_time > NS_MAX_SLEEP_AVG) - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |