[PATCH] patch-O1int-0306302317 for 2.5.73 interactivity

[Con Kolivas <kernel@kolivas.org>]

[-- Attachment #1: Type: text/plain, Size: 599 bytes --]

Buried deep in another mail thread was the latest implementation of my O1int 
patch so I've brought it to the surface to make it clear this one is 
significantly different from past iterations.

Summary:
Decreases audio skipping with loads.
Smooths out X performance with load.

I've also made it available here:
http://kernel.kolivas.org/2.5

along with a patch called granularity that is a modified version of Ingo's 
timeslice_granularity patch. It is no longer necessary and may slightly 
decrease throughput in non-desktop settings but put on top of my O1int patch 
makes X even smoother.

Con

[-- Attachment #2: patch-O1int-0306302317 --]
[-- Type: text/x-diff, Size: 3532 bytes --]

--- linux-2.5.73/kernel/sched.c	2003-06-30 10:06:40.000000000 +1000
+++ linux-2.5.73-test/kernel/sched.c	2003-06-30 23:16:42.000000000 +1000
@@ -314,11 +314,23 @@ static inline void enqueue_task(struct t
 static int effective_prio(task_t *p)
 {
 	int bonus, prio;
+	long sleep_period;

 	if (rt_task(p))
 		return p->prio;

-	bonus = MAX_USER_PRIO*PRIO_BONUS_RATIO*p->sleep_avg/MAX_SLEEP_AVG/100 -
+	sleep_period = jiffies - p->avg_start;
+
+	if (!sleep_period)
+		return p->static_prio;
+
+	if (sleep_period > MAX_SLEEP_AVG)
+		sleep_period = MAX_SLEEP_AVG;
+
+	if (p->sleep_avg > sleep_period)
+		sleep_period = p->sleep_avg;
+
+	bonus = MAX_USER_PRIO*PRIO_BONUS_RATIO*p->sleep_avg/sleep_period/100 -
 			MAX_USER_PRIO*PRIO_BONUS_RATIO/100/2;

 	prio = p->static_prio - bonus;
@@ -348,9 +360,19 @@ static inline void activate_task(task_t
 {
 	long sleep_time = jiffies - p->last_run - 1;

-	if (sleep_time > 0) {
-		int sleep_avg;
+	if (p->avg_start == 0){
+			p->avg_start = jiffies;
+			p->sleep_avg = 0;
+			sleep_time = 0;
+	}

+	if (sleep_time >= 0) {
+
+		if (sleep_time > HZ){
+			p->avg_start = jiffies;
+			p->sleep_avg = 0;
+		}
+		else {
 		/*
 		 * This code gives a bonus to interactive tasks.
 		 *
@@ -359,7 +381,7 @@ static inline void activate_task(task_t
 		 * spends sleeping, the higher the average gets - and the
 		 * higher the priority boost gets as well.
 		 */
-		sleep_avg = p->sleep_avg + sleep_time;
+			p->sleep_avg += sleep_time;

 		/*
 		 * 'Overflow' bonus ticks go to the waker as well, so the
@@ -367,12 +389,14 @@ static inline void activate_task(task_t
 		 * boosting tasks that are related to maximum-interactive
 		 * tasks.
 		 */
-		if (sleep_avg > MAX_SLEEP_AVG)
-			sleep_avg = MAX_SLEEP_AVG;
-		if (p->sleep_avg != sleep_avg) {
-			p->sleep_avg = sleep_avg;
-			p->prio = effective_prio(p);
+			if (p->sleep_avg > MAX_SLEEP_AVG * 12/10)
+				p->sleep_avg = MAX_SLEEP_AVG * 11/10;
+		}
+		if (unlikely(p->avg_start > jiffies)){
+			p->avg_start = jiffies;
+			p->sleep_avg = 0;
 		}
+		p->prio = effective_prio(p);
 	}
 	__activate_task(p, rq);
 }
@@ -549,8 +573,6 @@ void wake_up_forked_process(task_t * p)
 	 * and children as well, to keep max-interactive tasks
 	 * from forking tasks that are max-interactive.
 	 */
-	current->sleep_avg = current->sleep_avg * PARENT_PENALTY / 100;
-	p->sleep_avg = p->sleep_avg * CHILD_PENALTY / 100;
 	p->prio = effective_prio(p);
 	set_task_cpu(p, smp_processor_id());

@@ -586,13 +608,6 @@ void sched_exit(task_t * p)
 			p->parent->time_slice = MAX_TIMESLICE;
 	}
 	local_irq_restore(flags);
-	/*
-	 * If the child was a (relative-) CPU hog then decrease
-	 * the sleep_avg of the parent as well.
-	 */
-	if (p->sleep_avg < p->parent->sleep_avg)
-		p->parent->sleep_avg = (p->parent->sleep_avg * EXIT_WEIGHT +
-			p->sleep_avg) / (EXIT_WEIGHT + 1);
 }

 /**
--- linux-2.5.73/kernel/fork.c	2003-06-30 10:06:40.000000000 +1000
+++ linux-2.5.73-test/kernel/fork.c	2003-06-30 23:06:26.000000000 +1000
@@ -863,6 +863,7 @@ struct task_struct *copy_process(unsigne
 	p->array = NULL;
 	p->lock_depth = -1;		/* -1 = no lock */
 	p->start_time = get_jiffies_64();
+	p->avg_start = 0;
 	p->security = NULL;

 	retval = -ENOMEM;
--- linux-2.5.73/include/linux/sched.h	2003-06-30 10:06:40.000000000 +1000
+++ linux-2.5.73-test/include/linux/sched.h	2003-06-30 13:23:46.000000000 +1000
@@ -336,6 +336,7 @@ struct task_struct {
 	prio_array_t *array;

 	unsigned long sleep_avg;
+	unsigned long avg_start;
 	unsigned long last_run;

 	unsigned long policy;