Add a new stat,
- nr_migrations_cpu_non_preferred: number of migrations happened since
a CPU was marked as non preferred due to high steal time.
Signed-off-by: Shrikanth Hegde <sshegde@linux.ibm.com>
---
include/linux/sched.h | 1 +
kernel/sched/core.c | 9 +++++++--
kernel/sched/debug.c | 1 +
3 files changed, 9 insertions(+), 2 deletions(-)
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 968b18a7f470..37849d2f1dbd 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -554,6 +554,7 @@ struct sched_statistics {
u64 nr_failed_migrations_running;
u64 nr_failed_migrations_hot;
u64 nr_forced_migrations;
+ u64 nr_migrations_cpu_non_preferred;
u64 nr_wakeups;
u64 nr_wakeups_sync;diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index c51ba2979496..5fda8234e843 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -11336,8 +11336,13 @@ static int sched_non_preferred_cpu_push_stop(void *arg)
context_unsafe_alias(rq);
if (task_rq(p) == rq && task_on_rq_queued(p) &&
- !is_migration_disabled(p))
- rq = __migrate_task(rq, &rf, p, cpu);
+ !is_migration_disabled(p)) {
+ struct rq *dest_rq = __migrate_task(rq, &rf, p, cpu);
+
+ if (rq != dest_rq)
+ schedstat_inc(p->stats.nr_migrations_cpu_non_preferred);
+ rq = dest_rq;
+ }
rq_unlock(rq, &rf);
raw_spin_unlock_irq(&p->pi_lock);diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 72236db67983..5ebb2055e6d5 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -1446,6 +1446,7 @@ void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns,
P_SCHEDSTAT(nr_failed_migrations_running);
P_SCHEDSTAT(nr_failed_migrations_hot);
P_SCHEDSTAT(nr_forced_migrations);
+ P_SCHEDSTAT(nr_migrations_cpu_non_preferred);
P_SCHEDSTAT(nr_wakeups);
P_SCHEDSTAT(nr_wakeups_sync);
P_SCHEDSTAT(nr_wakeups_migrate);
--
2.47.3