Merge "Merge tag 'lsk-v4.4-16.12-android' into branch 'msm-4.4'"

6 files changed, 40 insertions, 15 deletions

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 57452c970a2b..312ffdad034a 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2044,6 +2044,28 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
 
 	success = 1; /* we're going to change ->state */
 
+	/*
+	 * Ensure we load p->on_rq _after_ p->state, otherwise it would
+	 * be possible to, falsely, observe p->on_rq == 0 and get stuck
+	 * in smp_cond_load_acquire() below.
+	 *
+	 * sched_ttwu_pending()                 try_to_wake_up()
+	 *   [S] p->on_rq = 1;                  [L] P->state
+	 *       UNLOCK rq->lock  -----.
+	 *                              \
+	 *				 +---   RMB
+	 * schedule()                   /
+	 *       LOCK rq->lock    -----'
+	 *       UNLOCK rq->lock
+	 *
+	 * [task p]
+	 *   [S] p->state = UNINTERRUPTIBLE     [L] p->on_rq
+	 *
+	 * Pairs with the UNLOCK+LOCK on rq->lock from the
+	 * last wakeup of our task and the schedule that got our task
+	 * current.
+	 */
+	smp_rmb();
 	if (p->on_rq && ttwu_remote(p, wake_flags))
 		goto stat;
 
@@ -9528,7 +9550,6 @@ struct cgroup_subsys cpu_cgrp_subsys = {
 	.fork		= cpu_cgroup_fork,
 	.can_attach	= cpu_cgroup_can_attach,
 	.attach		= cpu_cgroup_attach,
-	.allow_attach   = subsys_cgroup_allow_attach,
 	.legacy_cftypes	= cpu_files,
 	.early_init	= 1,
 };
diff --git a/kernel/sched/cpufreq_sched.c b/kernel/sched/cpufreq_sched.c
index f6f9b9b3a4a8..d751bc2d0d6e 100644
--- a/kernel/sched/cpufreq_sched.c
+++ b/kernel/sched/cpufreq_sched.c
@@ -289,7 +289,7 @@ static int cpufreq_sched_policy_init(struct cpufreq_policy *policy)
 	pr_debug("%s: throttle threshold = %u [ns]\n",
 		  __func__, gd->up_throttle_nsec);
 
-	rc = sysfs_create_group(get_governor_parent_kobj(policy), get_sysfs_attr());
+	rc = sysfs_create_group(&policy->kobj, get_sysfs_attr());
 	if (rc) {
 		pr_err("%s: couldn't create sysfs attributes: %d\n", __func__, rc);
 		goto err;
@@ -332,7 +332,7 @@ static int cpufreq_sched_policy_exit(struct cpufreq_policy *policy)
 		put_task_struct(gd->task);
 	}
 
-	sysfs_remove_group(get_governor_parent_kobj(policy), get_sysfs_attr());
+	sysfs_remove_group(&policy->kobj, get_sysfs_attr());
 
 	policy->governor_data = NULL;
 
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 00bbd91d6767..cf55fc2663fb 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -6845,17 +6845,19 @@ static inline int find_best_target(struct task_struct *p, bool boosted, bool pre
 
 		if (new_util < cur_capacity) {
 			if (cpu_rq(i)->nr_running) {
-				if(prefer_idle) {
-					// Find a target cpu with lowest
-					// utilization.
+				if (prefer_idle) {
+					/* Find a target cpu with highest
+					 * utilization.
+					 */
 					if (target_util == 0 ||
 						target_util < new_util) {
 						target_cpu = i;
 						target_util = new_util;
 					}
 				} else {
-					// Find a target cpu with highest
-					// utilization.
+					/* Find a target cpu with lowest
+					 * utilization.
+					 */
 					if (target_util == 0 ||
 						target_util > new_util) {
 						target_cpu = i;
@@ -8382,7 +8384,8 @@ static void update_cpu_capacity(struct sched_domain *sd, int cpu)
 		mcc->cpu = cpu;
 #ifdef CONFIG_SCHED_DEBUG
 		raw_spin_unlock_irqrestore(&mcc->lock, flags);
-		pr_info("CPU%d: update max cpu_capacity %lu\n", cpu, capacity);
+		printk_deferred(KERN_INFO "CPU%d: update max cpu_capacity %lu\n",
+				cpu, capacity);
 		goto skip_unlock;
 #endif
 	}
diff --git a/kernel/sched/features.h b/kernel/sched/features.h
index 7cc74e56fde4..c30c48fde7e6 100644
--- a/kernel/sched/features.h
+++ b/kernel/sched/features.h
@@ -73,4 +73,8 @@ SCHED_FEAT(ATTACH_AGE_LOAD, true)
  * Energy aware scheduling. Use platform energy model to guide scheduling
  * decisions optimizing for energy efficiency.
  */
+#ifdef CONFIG_DEFAULT_USE_ENERGY_AWARE
+SCHED_FEAT(ENERGY_AWARE, true)
+#else
 SCHED_FEAT(ENERGY_AWARE, false)
+#endif
diff --git a/kernel/sched/tune.c b/kernel/sched/tune.c
index b2ff383d6062..b0c5fe6d1f3b 100644
--- a/kernel/sched/tune.c
+++ b/kernel/sched/tune.c
@@ -896,7 +896,6 @@ struct cgroup_subsys schedtune_cgrp_subsys = {
 	.cancel_attach  = schedtune_cancel_attach,
 	.legacy_cftypes	= files,
 	.early_init	= 1,
-	.allow_attach	= subsys_cgroup_allow_attach,
 	.attach		= schedtune_attach,
 };
 
@@ -910,6 +909,7 @@ schedtune_init_cgroups(void)
 	for_each_possible_cpu(cpu) {
 		bg = &per_cpu(cpu_boost_groups, cpu);
 		memset(bg, 0, sizeof(struct boost_groups));
+		raw_spin_lock_init(&bg->lock);
 	}
 
 	pr_info("schedtune: configured to support %d boost groups\n",
diff --git a/kernel/sched/walt.c b/kernel/sched/walt.c
index 07b7f84b37e2..2ffb1680b380 100644
--- a/kernel/sched/walt.c
+++ b/kernel/sched/walt.c
@@ -22,7 +22,6 @@
 #include <linux/syscore_ops.h>
 #include <linux/cpufreq.h>
 #include <trace/events/sched.h>
-#include <clocksource/arm_arch_timer.h>
 #include "sched.h"
 #include "walt.h"
 
@@ -188,10 +187,8 @@ update_window_start(struct rq *rq, u64 wallclock)
 	delta = wallclock - rq->window_start;
 	/* If the MPM global timer is cleared, set delta as 0 to avoid kernel BUG happening */
 	if (delta < 0) {
-		if (arch_timer_read_counter() == 0)
-			delta = 0;
-		else
-			BUG_ON(1);
+		delta = 0;
+		WARN_ONCE(1, "WALT wallclock appears to have gone backwards or reset\n");
 	}
 
 	if (delta < walt_ravg_window)