sched/walt: Improve the scheduler
This change is for general scheduler improvements.
Change-Id: I84f84973b815fb0bb95d1d950a4ac90be11f9470
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 705f76d..a9db959 100755
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -2712,15 +2712,14 @@
#if defined(CONFIG_SCHED_TUNE) && defined(CONFIG_CGROUP_SCHEDTUNE)
extern bool task_sched_boost(struct task_struct *p);
extern int sync_cgroup_colocation(struct task_struct *p, bool insert);
-extern bool same_schedtune(struct task_struct *tsk1, struct task_struct *tsk2);
+extern bool schedtune_task_colocated(struct task_struct *p);
extern void update_cgroup_boost_settings(void);
extern void restore_cgroup_boost_settings(void);
#else
-static inline bool
-same_schedtune(struct task_struct *tsk1, struct task_struct *tsk2)
+static inline bool schedtune_task_colocated(struct task_struct *p)
{
- return true;
+ return false;
}
static inline bool task_sched_boost(struct task_struct *p)
diff --git a/kernel/sched/tune.c b/kernel/sched/tune.c
index 92fcb92..90d8fad 100644
--- a/kernel/sched/tune.c
+++ b/kernel/sched/tune.c
@@ -344,11 +344,6 @@
st->colocate_update_disabled = false;
}
-bool same_schedtune(struct task_struct *tsk1, struct task_struct *tsk2)
-{
- return task_schedtune(tsk1) == task_schedtune(tsk2);
-}
-
void update_cgroup_boost_settings(void)
{
int i;
@@ -658,6 +653,23 @@
return 0;
}
+bool schedtune_task_colocated(struct task_struct *p)
+{
+ struct schedtune *st;
+ bool colocated;
+
+ if (unlikely(!schedtune_initialized))
+ return false;
+
+ /* Get task boost value */
+ rcu_read_lock();
+ st = task_schedtune(p);
+ colocated = st->colocate;
+ rcu_read_unlock();
+
+ return colocated;
+}
+
#else /* CONFIG_SCHED_WALT */
static inline void init_sched_boost(struct schedtune *st) { }
diff --git a/kernel/sched/walt.c b/kernel/sched/walt.c
index 0050ca5..578e4c4 100755
--- a/kernel/sched/walt.c
+++ b/kernel/sched/walt.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2016-2019, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2016-2020, The Linux Foundation. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
@@ -2559,7 +2559,6 @@
* Enable colocation and frequency aggregation for all threads in a process.
* The children inherits the group id from the parent.
*/
-unsigned int __read_mostly sysctl_sched_enable_thread_grouping;
/* Maximum allowed threshold before freq aggregation must be enabled */
#define MAX_FREQ_AGGR_THRESH 1000
@@ -2853,34 +2852,25 @@
{
unsigned long flags;
struct related_thread_group *grp;
- struct task_struct *leader = new->group_leader;
- unsigned int leader_grp_id = sched_get_group_id(leader);
- if (!sysctl_sched_enable_thread_grouping &&
- leader_grp_id != DEFAULT_CGROUP_COLOC_ID)
+ /*
+ * If the task does not belong to colocated schedtune
+ * cgroup, nothing to do. We are checking this without
+ * lock. Even if there is a race, it will be added
+ * to the co-located cgroup via cgroup attach.
+ */
+ if (!schedtune_task_colocated(new))
return;
- if (thread_group_leader(new))
- return;
-
- if (leader_grp_id == DEFAULT_CGROUP_COLOC_ID) {
- if (!same_schedtune(new, leader))
- return;
- }
-
+ grp = lookup_related_thread_group(DEFAULT_CGROUP_COLOC_ID);
write_lock_irqsave(&related_thread_group_lock, flags);
- rcu_read_lock();
- grp = task_related_thread_group(leader);
- rcu_read_unlock();
-
/*
* It's possible that someone already added the new task to the
- * group. A leader's thread group is updated prior to calling
- * this function. It's also possible that the leader has exited
- * the group. In either case, there is nothing else to do.
+ * group. or it might have taken out from the colocated schedtune
+ * cgroup. check these conditions under lock.
*/
- if (!grp || new->grp) {
+ if (!schedtune_task_colocated(new) || new->grp) {
write_unlock_irqrestore(&related_thread_group_lock, flags);
return;
}