12/13
Add SCHEDSTAT statistics for sched-balance-fork.
Signed-off-by: Nick Piggin <[EMAIL PROTECTED]>
Index: linux-2.6/include/linux/sched.h
===================================================================
--- linux-2.6.orig/include/linux/sched.h 2005-02-24 17:39:07.616911007 +1100
+++ linux-2.6/include/linux/sched.h 2005-02-24 17:39:07.819885956 +1100
@@ -480,10 +480,16 @@
unsigned long alb_failed;
unsigned long alb_pushed;
- /* sched_balance_exec() stats */
- unsigned long sbe_attempts;
+ /* SD_BALANCE_EXEC stats */
+ unsigned long sbe_cnt;
+ unsigned long sbe_balanced;
unsigned long sbe_pushed;
+ /* SD_BALANCE_FORK stats */
+ unsigned long sbf_cnt;
+ unsigned long sbf_balanced;
+ unsigned long sbf_pushed;
+
/* try_to_wake_up() stats */
unsigned long ttwu_wake_remote;
unsigned long ttwu_move_affine;
Index: linux-2.6/kernel/sched.c
===================================================================
--- linux-2.6.orig/kernel/sched.c 2005-02-24 17:39:07.618910761 +1100
+++ linux-2.6/kernel/sched.c 2005-02-24 17:43:36.887683960 +1100
@@ -307,7 +307,7 @@
* bump this up when changing the output format or the meaning of an existing
* format, so that tools can adapt (or abort)
*/
-#define SCHEDSTAT_VERSION 11
+#define SCHEDSTAT_VERSION 12
static int show_schedstat(struct seq_file *seq, void *v)
{
@@ -354,9 +354,10 @@
sd->lb_nobusyq[itype],
sd->lb_nobusyg[itype]);
}
- seq_printf(seq, " %lu %lu %lu %lu %lu %lu %lu %lu\n",
+ seq_printf(seq, " %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu %lu\n",
sd->alb_cnt, sd->alb_failed, sd->alb_pushed,
- sd->sbe_pushed, sd->sbe_attempts,
+ sd->sbe_cnt, sd->sbe_balanced, sd->sbe_pushed,
+ sd->sbf_cnt, sd->sbf_balanced, sd->sbf_pushed,
sd->ttwu_wake_remote, sd->ttwu_move_affine, sd->ttwu_move_balance);
}
#endif
@@ -1262,24 +1263,34 @@
sd = tmp;
if (sd) {
+ int new_cpu;
struct sched_group *group;
+ schedstat_inc(sd, sbf_cnt);
cpu = task_cpu(p);
group = find_idlest_group(sd, p, cpu);
- if (group) {
- int new_cpu;
- new_cpu = find_idlest_cpu(group, cpu);
- if (new_cpu != -1 && new_cpu != cpu &&
- cpu_isset(new_cpu, p->cpus_allowed)) {
- set_task_cpu(p, new_cpu);
- task_rq_unlock(rq, &flags);
- rq = task_rq_lock(p, &flags);
- cpu = task_cpu(p);
- }
+ if (!group) {
+ schedstat_inc(sd, sbf_balanced);
+ goto no_forkbalance;
+ }
+
+ new_cpu = find_idlest_cpu(group, cpu);
+ if (new_cpu == -1 || new_cpu == cpu) {
+ schedstat_inc(sd, sbf_balanced);
+ goto no_forkbalance;
+ }
+
+ if (cpu_isset(new_cpu, p->cpus_allowed)) {
+ schedstat_inc(sd, sbf_pushed);
+ set_task_cpu(p, new_cpu);
+ task_rq_unlock(rq, &flags);
+ rq = task_rq_lock(p, &flags);
+ cpu = task_cpu(p);
}
}
-#endif
+no_forkbalance:
+#endif
/*
* We decrease the sleep average of forking parents
* and children as well, to keep max-interactive tasks
@@ -1616,30 +1627,28 @@
struct sched_domain *tmp, *sd = NULL;
int new_cpu, this_cpu = get_cpu();
- /* Prefer the current CPU if there's only this task running */
- if (this_rq()->nr_running <= 1)
- goto out;
-
for_each_domain(this_cpu, tmp)
if (tmp->flags & SD_BALANCE_EXEC)
sd = tmp;
if (sd) {
struct sched_group *group;
- schedstat_inc(sd, sbe_attempts);
+ schedstat_inc(sd, sbe_cnt);
group = find_idlest_group(sd, current, this_cpu);
- if (!group)
+ if (!group) {
+ schedstat_inc(sd, sbe_balanced);
goto out;
+ }
new_cpu = find_idlest_cpu(group, this_cpu);
- if (new_cpu == -1)
+ if (new_cpu == -1 || new_cpu == this_cpu) {
+ schedstat_inc(sd, sbe_balanced);
goto out;
-
- if (new_cpu != this_cpu) {
- schedstat_inc(sd, sbe_pushed);
- put_cpu();
- sched_migrate_task(current, new_cpu);
- return;
}
+
+ schedstat_inc(sd, sbe_pushed);
+ put_cpu();
+ sched_migrate_task(current, new_cpu);
+ return;
}
out:
put_cpu();
