From d425b274ba83ba4e7746a40446ec0ba3267de51f Mon Sep 17 00:00:00 2001 From: Con Kolivas Date: Fri, 31 Mar 2006 02:31:29 -0800 Subject: [PATCH] [PATCH] sched: activate SCHED BATCH expired 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 Acked-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/sched.h | 1 + kernel/sched.c | 10 +++++++--- 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index c4fd3fc..78c40dd 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -484,6 +484,7 @@ 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.. diff --git a/kernel/sched.c b/kernel/sched.c index 73bb4d9..dd153d6 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -667,9 +667,13 @@ static int effective_prio(task_t *p) /* * __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); rq->nr_running++; } @@ -688,7 +692,7 @@ static int recalc_task_prio(task_t *p, unsigned long long now) 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) -- 2.7.4