Adding upstream version 6.8.9.upstream/6.8.9

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

11 files changed, 781 insertions, 600 deletions

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index a708d225c2..9116bcc903 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -57,6 +57,7 @@
 #include <linux/profile.h>
 #include <linux/psi.h>
 #include <linux/rcuwait_api.h>
+#include <linux/rseq.h>
 #include <linux/sched/wake_q.h>
 #include <linux/scs.h>
 #include <linux/slab.h>
@@ -1131,6 +1132,28 @@ static void wake_up_idle_cpu(int cpu)
 	if (cpu == smp_processor_id())
 		return;
 
+	/*
+	 * Set TIF_NEED_RESCHED and send an IPI if in the non-polling
+	 * part of the idle loop. This forces an exit from the idle loop
+	 * and a round trip to schedule(). Now this could be optimized
+	 * because a simple new idle loop iteration is enough to
+	 * re-evaluate the next tick. Provided some re-ordering of tick
+	 * nohz functions that would need to follow TIF_NR_POLLING
+	 * clearing:
+	 *
+	 * - On most archs, a simple fetch_or on ti::flags with a
+	 *   "0" value would be enough to know if an IPI needs to be sent.
+	 *
+	 * - x86 needs to perform a last need_resched() check between
+	 *   monitor and mwait which doesn't take timers into account.
+	 *   There a dedicated TIF_TIMER flag would be required to
+	 *   fetch_or here and be checked along with TIF_NEED_RESCHED
+	 *   before mwait().
+	 *
+	 * However, remote timer enqueue is not such a frequent event
+	 * and testing of the above solutions didn't appear to report
+	 * much benefits.
+	 */
 	if (set_nr_and_not_polling(rq->idle))
 		smp_send_reschedule(cpu);
 	else
@@ -2124,12 +2147,14 @@ void activate_task(struct rq *rq, struct task_struct *p, int flags)
 
 	enqueue_task(rq, p, flags);
 
-	p->on_rq = TASK_ON_RQ_QUEUED;
+	WRITE_ONCE(p->on_rq, TASK_ON_RQ_QUEUED);
+	ASSERT_EXCLUSIVE_WRITER(p->on_rq);
 }
 
 void deactivate_task(struct rq *rq, struct task_struct *p, int flags)
 {
-	p->on_rq = (flags & DEQUEUE_SLEEP) ? 0 : TASK_ON_RQ_MIGRATING;
+	WRITE_ONCE(p->on_rq, (flags & DEQUEUE_SLEEP) ? 0 : TASK_ON_RQ_MIGRATING);
+	ASSERT_EXCLUSIVE_WRITER(p->on_rq);
 
 	dequeue_task(rq, p, flags);
 }
@@ -3795,6 +3820,8 @@ ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags,
 		rq->idle_stamp = 0;
 	}
 #endif
+
+	p->dl_server = NULL;
 }
 
 /*
@@ -4509,10 +4536,7 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p)
 	memset(&p->stats, 0, sizeof(p->stats));
 #endif
 
-	RB_CLEAR_NODE(&p->dl.rb_node);
-	init_dl_task_timer(&p->dl);
-	init_dl_inactive_task_timer(&p->dl);
-	__dl_clear_params(p);
+	init_dl_entity(&p->dl);
 
 	INIT_LIST_HEAD(&p->rt.run_list);
 	p->rt.timeout		= 0;
@@ -6004,12 +6028,27 @@ __pick_next_task(struct rq *rq, struct task_struct *prev, struct rq_flags *rf)
 			p = pick_next_task_idle(rq);
 		}
 
+		/*
+		 * This is the fast path; it cannot be a DL server pick;
+		 * therefore even if @p == @prev, ->dl_server must be NULL.
+		 */
+		if (p->dl_server)
+			p->dl_server = NULL;
+
 		return p;
 	}
 
 restart:
 	put_prev_task_balance(rq, prev, rf);
 
+	/*
+	 * We've updated @prev and no longer need the server link, clear it.
+	 * Must be done before ->pick_next_task() because that can (re)set
+	 * ->dl_server.
+	 */
+	if (prev->dl_server)
+		prev->dl_server = NULL;
+
 	for_each_class(class) {
 		p = class->pick_next_task(rq);
 		if (p)
@@ -7429,18 +7468,13 @@ int sched_core_idle_cpu(int cpu)
  * required to meet deadlines.
  */
 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
-				 enum cpu_util_type type,
-				 struct task_struct *p)
+				 unsigned long *min,
+				 unsigned long *max)
 {
-	unsigned long dl_util, util, irq, max;
+	unsigned long util, irq, scale;
 	struct rq *rq = cpu_rq(cpu);
 
-	max = arch_scale_cpu_capacity(cpu);
-
-	if (!uclamp_is_used() &&
-	    type == FREQUENCY_UTIL && rt_rq_is_runnable(&rq->rt)) {
-		return max;
-	}
+	scale = arch_scale_cpu_capacity(cpu);
 
 	/*
 	 * Early check to see if IRQ/steal time saturates the CPU, can be
@@ -7448,45 +7482,49 @@ unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
 	 * update_irq_load_avg().
 	 */
 	irq = cpu_util_irq(rq);
-	if (unlikely(irq >= max))
-		return max;
+	if (unlikely(irq >= scale)) {
+		if (min)
+			*min = scale;
+		if (max)
+			*max = scale;
+		return scale;
+	}
+
+	if (min) {
+		/*
+		 * The minimum utilization returns the highest level between:
+		 * - the computed DL bandwidth needed with the IRQ pressure which
+		 *   steals time to the deadline task.
+		 * - The minimum performance requirement for CFS and/or RT.
+		 */
+		*min = max(irq + cpu_bw_dl(rq), uclamp_rq_get(rq, UCLAMP_MIN));
+
+		/*
+		 * When an RT task is runnable and uclamp is not used, we must
+		 * ensure that the task will run at maximum compute capacity.
+		 */
+		if (!uclamp_is_used() && rt_rq_is_runnable(&rq->rt))
+			*min = max(*min, scale);
+	}
 
 	/*
 	 * Because the time spend on RT/DL tasks is visible as 'lost' time to
 	 * CFS tasks and we use the same metric to track the effective
 	 * utilization (PELT windows are synchronized) we can directly add them
 	 * to obtain the CPU's actual utilization.
-	 *
-	 * CFS and RT utilization can be boosted or capped, depending on
-	 * utilization clamp constraints requested by currently RUNNABLE
-	 * tasks.
-	 * When there are no CFS RUNNABLE tasks, clamps are released and
-	 * frequency will be gracefully reduced with the utilization decay.
 	 */
 	util = util_cfs + cpu_util_rt(rq);
-	if (type == FREQUENCY_UTIL)
-		util = uclamp_rq_util_with(rq, util, p);
-
-	dl_util = cpu_util_dl(rq);
+	util += cpu_util_dl(rq);
 
 	/*
-	 * For frequency selection we do not make cpu_util_dl() a permanent part
-	 * of this sum because we want to use cpu_bw_dl() later on, but we need
-	 * to check if the CFS+RT+DL sum is saturated (ie. no idle time) such
-	 * that we select f_max when there is no idle time.
-	 *
-	 * NOTE: numerical errors or stop class might cause us to not quite hit
-	 * saturation when we should -- something for later.
+	 * The maximum hint is a soft bandwidth requirement, which can be lower
+	 * than the actual utilization because of uclamp_max requirements.
 	 */
-	if (util + dl_util >= max)
-		return max;
+	if (max)
+		*max = min(scale, uclamp_rq_get(rq, UCLAMP_MAX));
 
-	/*
-	 * OTOH, for energy computation we need the estimated running time, so
-	 * include util_dl and ignore dl_bw.
-	 */
-	if (type == ENERGY_UTIL)
-		util += dl_util;
+	if (util >= scale)
+		return scale;
 
 	/*
 	 * There is still idle time; further improve the number by using the
@@ -7497,28 +7535,15 @@ unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
 	 *   U' = irq + --------- * U
 	 *                 max
 	 */
-	util = scale_irq_capacity(util, irq, max);
+	util = scale_irq_capacity(util, irq, scale);
 	util += irq;
 
-	/*
-	 * Bandwidth required by DEADLINE must always be granted while, for
-	 * FAIR and RT, we use blocked utilization of IDLE CPUs as a mechanism
-	 * to gracefully reduce the frequency when no tasks show up for longer
-	 * periods of time.
-	 *
-	 * Ideally we would like to set bw_dl as min/guaranteed freq and util +
-	 * bw_dl as requested freq. However, cpufreq is not yet ready for such
-	 * an interface. So, we only do the latter for now.
-	 */
-	if (type == FREQUENCY_UTIL)
-		util += cpu_bw_dl(rq);
-
-	return min(max, util);
+	return min(scale, util);
 }
 
 unsigned long sched_cpu_util(int cpu)
 {
-	return effective_cpu_util(cpu, cpu_util_cfs(cpu), ENERGY_UTIL, NULL);
+	return effective_cpu_util(cpu, cpu_util_cfs(cpu), NULL, NULL);
 }
 #endif /* CONFIG_SMP */
 
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index 5888176354..eece6244f9 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -47,7 +47,7 @@ struct sugov_cpu {
 	u64			last_update;
 
 	unsigned long		util;
-	unsigned long		bw_dl;
+	unsigned long		bw_min;
 
 	/* The field below is for single-CPU policies only: */
 #ifdef CONFIG_NO_HZ_COMMON
@@ -115,6 +115,32 @@ static void sugov_deferred_update(struct sugov_policy *sg_policy)
 }
 
 /**
+ * get_capacity_ref_freq - get the reference frequency that has been used to
+ * correlate frequency and compute capacity for a given cpufreq policy. We use
+ * the CPU managing it for the arch_scale_freq_ref() call in the function.
+ * @policy: the cpufreq policy of the CPU in question.
+ *
+ * Return: the reference CPU frequency to compute a capacity.
+ */
+static __always_inline
+unsigned long get_capacity_ref_freq(struct cpufreq_policy *policy)
+{
+	unsigned int freq = arch_scale_freq_ref(policy->cpu);
+
+	if (freq)
+		return freq;
+
+	if (arch_scale_freq_invariant())
+		return policy->cpuinfo.max_freq;
+
+	/*
+	 * Apply a 25% margin so that we select a higher frequency than
+	 * the current one before the CPU is fully busy:
+	 */
+	return policy->cur + (policy->cur >> 2);
+}
+
+/**
  * get_next_freq - Compute a new frequency for a given cpufreq policy.
  * @sg_policy: schedutil policy object to compute the new frequency for.
  * @util: Current CPU utilization.
@@ -140,10 +166,9 @@ static unsigned int get_next_freq(struct sugov_policy *sg_policy,
 				  unsigned long util, unsigned long max)
 {
 	struct cpufreq_policy *policy = sg_policy->policy;
-	unsigned int freq = arch_scale_freq_invariant() ?
-				policy->cpuinfo.max_freq : policy->cur;
+	unsigned int freq;
 
-	util = map_util_perf(util);
+	freq = get_capacity_ref_freq(policy);
 	freq = map_util_freq(util, freq, max);
 
 	if (freq == sg_policy->cached_raw_freq && !sg_policy->need_freq_update)
@@ -153,14 +178,31 @@ static unsigned int get_next_freq(struct sugov_policy *sg_policy,
 	return cpufreq_driver_resolve_freq(policy, freq);
 }
 
-static void sugov_get_util(struct sugov_cpu *sg_cpu)
+unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual,
+				 unsigned long min,
+				 unsigned long max)
+{
+	/* Add dvfs headroom to actual utilization */
+	actual = map_util_perf(actual);
+	/* Actually we don't need to target the max performance */
+	if (actual < max)
+		max = actual;
+
+	/*
+	 * Ensure at least minimum performance while providing more compute
+	 * capacity when possible.
+	 */
+	return max(min, max);
+}
+
+static void sugov_get_util(struct sugov_cpu *sg_cpu, unsigned long boost)
 {
-	unsigned long util = cpu_util_cfs_boost(sg_cpu->cpu);
-	struct rq *rq = cpu_rq(sg_cpu->cpu);
+	unsigned long min, max, util = cpu_util_cfs_boost(sg_cpu->cpu);
 
-	sg_cpu->bw_dl = cpu_bw_dl(rq);
-	sg_cpu->util = effective_cpu_util(sg_cpu->cpu, util,
-					  FREQUENCY_UTIL, NULL);
+	util = effective_cpu_util(sg_cpu->cpu, util, &min, &max);
+	util = max(util, boost);
+	sg_cpu->bw_min = min;
+	sg_cpu->util = sugov_effective_cpu_perf(sg_cpu->cpu, util, min, max);
 }
 
 /**
@@ -251,18 +293,16 @@ static void sugov_iowait_boost(struct sugov_cpu *sg_cpu, u64 time,
  * This mechanism is designed to boost high frequently IO waiting tasks, while
  * being more conservative on tasks which does sporadic IO operations.
  */
-static void sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time,
+static unsigned long sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time,
 			       unsigned long max_cap)
 {
-	unsigned long boost;
-
 	/* No boost currently required */
 	if (!sg_cpu->iowait_boost)
-		return;
+		return 0;
 
 	/* Reset boost if the CPU appears to have been idle enough */
 	if (sugov_iowait_reset(sg_cpu, time, false))
-		return;
+		return 0;
 
 	if (!sg_cpu->iowait_boost_pending) {
 		/*
@@ -271,7 +311,7 @@ static void sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time,
 		sg_cpu->iowait_boost >>= 1;
 		if (sg_cpu->iowait_boost < IOWAIT_BOOST_MIN) {
 			sg_cpu->iowait_boost = 0;
-			return;
+			return 0;
 		}
 	}
 
@@ -281,10 +321,7 @@ static void sugov_iowait_apply(struct sugov_cpu *sg_cpu, u64 time,
 	 * sg_cpu->util is already in capacity scale; convert iowait_boost
 	 * into the same scale so we can compare.
 	 */
-	boost = (sg_cpu->iowait_boost * max_cap) >> SCHED_CAPACITY_SHIFT;
-	boost = uclamp_rq_util_with(cpu_rq(sg_cpu->cpu), boost, NULL);
-	if (sg_cpu->util < boost)
-		sg_cpu->util = boost;
+	return (sg_cpu->iowait_boost * max_cap) >> SCHED_CAPACITY_SHIFT;
 }
 
 #ifdef CONFIG_NO_HZ_COMMON
@@ -306,7 +343,7 @@ static inline bool sugov_cpu_is_busy(struct sugov_cpu *sg_cpu) { return false; }
  */
 static inline void ignore_dl_rate_limit(struct sugov_cpu *sg_cpu)
 {
-	if (cpu_bw_dl(cpu_rq(sg_cpu->cpu)) > sg_cpu->bw_dl)
+	if (cpu_bw_dl(cpu_rq(sg_cpu->cpu)) > sg_cpu->bw_min)
 		sg_cpu->sg_policy->limits_changed = true;
 }
 
@@ -314,6 +351,8 @@ static inline bool sugov_update_single_common(struct sugov_cpu *sg_cpu,
 					      u64 time, unsigned long max_cap,
 					      unsigned int flags)
 {
+	unsigned long boost;
+
 	sugov_iowait_boost(sg_cpu, time, flags);
 	sg_cpu->last_update = time;
 
@@ -322,8 +361,8 @@ static inline bool sugov_update_single_common(struct sugov_cpu *sg_cpu,
 	if (!sugov_should_update_freq(sg_cpu->sg_policy, time))
 		return false;
 
-	sugov_get_util(sg_cpu);
-	sugov_iowait_apply(sg_cpu, time, max_cap);
+	boost = sugov_iowait_apply(sg_cpu, time, max_cap);
+	sugov_get_util(sg_cpu, boost);
 
 	return true;
 }
@@ -407,8 +446,8 @@ static void sugov_update_single_perf(struct update_util_data *hook, u64 time,
 	    sugov_cpu_is_busy(sg_cpu) && sg_cpu->util < prev_util)
 		sg_cpu->util = prev_util;
 
-	cpufreq_driver_adjust_perf(sg_cpu->cpu, map_util_perf(sg_cpu->bw_dl),
-				   map_util_perf(sg_cpu->util), max_cap);
+	cpufreq_driver_adjust_perf(sg_cpu->cpu, sg_cpu->bw_min,
+				   sg_cpu->util, max_cap);
 
 	sg_cpu->sg_policy->last_freq_update_time = time;
 }
@@ -424,9 +463,10 @@ static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu, u64 time)
 
 	for_each_cpu(j, policy->cpus) {
 		struct sugov_cpu *j_sg_cpu = &per_cpu(sugov_cpu, j);
+		unsigned long boost;
 
-		sugov_get_util(j_sg_cpu);
-		sugov_iowait_apply(j_sg_cpu, time, max_cap);
+		boost = sugov_iowait_apply(j_sg_cpu, time, max_cap);
+		sugov_get_util(j_sg_cpu, boost);
 
 		util = max(j_sg_cpu->util, util);
 	}
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index b28114478b..a04a436af8 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -54,8 +54,14 @@ static int __init sched_dl_sysctl_init(void)
 late_initcall(sched_dl_sysctl_init);
 #endif
 
+static bool dl_server(struct sched_dl_entity *dl_se)
+{
+	return dl_se->dl_server;
+}
+
 static inline struct task_struct *dl_task_of(struct sched_dl_entity *dl_se)
 {
+	BUG_ON(dl_server(dl_se));
 	return container_of(dl_se, struct task_struct, dl);
 }
 
@@ -64,12 +70,19 @@ static inline struct rq *rq_of_dl_rq(struct dl_rq *dl_rq)
 	return container_of(dl_rq, struct rq, dl);
 }
 
-static inline struct dl_rq *dl_rq_of_se(struct sched_dl_entity *dl_se)
+static inline struct rq *rq_of_dl_se(struct sched_dl_entity *dl_se)
 {
-	struct task_struct *p = dl_task_of(dl_se);
-	struct rq *rq = task_rq(p);
+	struct rq *rq = dl_se->rq;
+
+	if (!dl_server(dl_se))
+		rq = task_rq(dl_task_of(dl_se));
+
+	return rq;
+}
 
-	return &rq->dl;
+static inline struct dl_rq *dl_rq_of_se(struct sched_dl_entity *dl_se)
+{
+	return &rq_of_dl_se(dl_se)->dl;
 }
 
 static inline int on_dl_rq(struct sched_dl_entity *dl_se)
@@ -335,6 +348,8 @@ static void dl_change_utilization(struct task_struct *p, u64 new_bw)
 	__add_rq_bw(new_bw, &rq->dl);
 }
 
+static void __dl_clear_params(struct sched_dl_entity *dl_se);
+
 /*
  * The utilization of a task cannot be immediately removed from
  * the rq active utilization (running_bw) when the task blocks.
@@ -389,12 +404,11 @@ static void dl_change_utilization(struct task_struct *p, u64 new_bw)
  * up, and checks if the task is still in the "ACTIVE non contending"
  * state or not (in the second case, it updates running_bw).
  */
-static void task_non_contending(struct task_struct *p)
+static void task_non_contending(struct sched_dl_entity *dl_se)
 {
-	struct sched_dl_entity *dl_se = &p->dl;
 	struct hrtimer *timer = &dl_se->inactive_timer;
-	struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
-	struct rq *rq = rq_of_dl_rq(dl_rq);
+	struct rq *rq = rq_of_dl_se(dl_se);
+	struct dl_rq *dl_rq = &rq->dl;
 	s64 zerolag_time;
 
 	/*
@@ -424,24 +438,33 @@ static void task_non_contending(struct task_struct *p)
 	 * utilization now, instead of starting a timer
 	 */
 	if ((zerolag_time < 0) || hrtimer_active(&dl_se->inactive_timer)) {
-		if (dl_task(p))
+		if (dl_server(dl_se)) {
 			sub_running_bw(dl_se, dl_rq);
-		if (!dl_task(p) || READ_ONCE(p->__state) == TASK_DEAD) {
-			struct dl_bw *dl_b = dl_bw_of(task_cpu(p));
-
-			if (READ_ONCE(p->__state) == TASK_DEAD)
-				sub_rq_bw(&p->dl, &rq->dl);
-			raw_spin_lock(&dl_b->lock);
-			__dl_sub(dl_b, p->dl.dl_bw, dl_bw_cpus(task_cpu(p)));
-			raw_spin_unlock(&dl_b->lock);
-			__dl_clear_params(p);
+		} else {
+			struct task_struct *p = dl_task_of(dl_se);
+
+			if (dl_task(p))
+				sub_running_bw(dl_se, dl_rq);
+
+			if (!dl_task(p) || READ_ONCE(p->__state) == TASK_DEAD) {
+				struct dl_bw *dl_b = dl_bw_of(task_cpu(p));
+
+				if (READ_ONCE(p->__state) == TASK_DEAD)
+					sub_rq_bw(dl_se, &rq->dl);
+				raw_spin_lock(&dl_b->lock);
+				__dl_sub(dl_b, dl_se->dl_bw, dl_bw_cpus(task_cpu(p)));
+				raw_spin_unlock(&dl_b->lock);
+				__dl_clear_params(dl_se);
+			}
 		}
 
 		return;
 	}
 
 	dl_se->dl_non_contending = 1;
-	get_task_struct(p);
+	if (!dl_server(dl_se))
+		get_task_struct(dl_task_of(dl_se));
+
 	hrtimer_start(timer, ns_to_ktime(zerolag_time), HRTIMER_MODE_REL_HARD);
 }
 
@@ -468,8 +491,10 @@ static void task_contending(struct sched_dl_entity *dl_se, int flags)
 		 * will not touch the rq's active utilization,
 		 * so we are still safe.
 		 */
-		if (hrtimer_try_to_cancel(&dl_se->inactive_timer) == 1)
-			put_task_struct(dl_task_of(dl_se));
+		if (hrtimer_try_to_cancel(&dl_se->inactive_timer) == 1) {
+			if (!dl_server(dl_se))
+				put_task_struct(dl_task_of(dl_se));
+		}
 	} else {
 		/*
 		 * Since "dl_non_contending" is not set, the
@@ -482,10 +507,8 @@ static void task_contending(struct sched_dl_entity *dl_se, int flags)
 	}
 }
 
-static inline int is_leftmost(struct task_struct *p, struct dl_rq *dl_rq)
+static inline int is_leftmost(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
 {
-	struct sched_dl_entity *dl_se = &p->dl;
-
 	return rb_first_cached(&dl_rq->root) == &dl_se->rb_node;
 }
 
@@ -737,8 +760,10 @@ static inline void deadline_queue_pull_task(struct rq *rq)
 }
 #endif /* CONFIG_SMP */
 
+static void
+enqueue_dl_entity(struct sched_dl_entity *dl_se, int flags);
 static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags);
-static void __dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags);
+static void dequeue_dl_entity(struct sched_dl_entity *dl_se, int flags);
 static void wakeup_preempt_dl(struct rq *rq, struct task_struct *p, int flags);
 
 static inline void replenish_dl_new_period(struct sched_dl_entity *dl_se,
@@ -986,8 +1011,7 @@ static inline bool dl_is_implicit(struct sched_dl_entity *dl_se)
  */
 static void update_dl_entity(struct sched_dl_entity *dl_se)
 {
-	struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
-	struct rq *rq = rq_of_dl_rq(dl_rq);
+	struct rq *rq = rq_of_dl_se(dl_se);
 
 	if (dl_time_before(dl_se->deadline, rq_clock(rq)) ||
 	    dl_entity_overflow(dl_se, rq_clock(rq))) {
@@ -1018,11 +1042,11 @@ static inline u64 dl_next_period(struct sched_dl_entity *dl_se)
  * actually started or not (i.e., the replenishment instant is in
  * the future or in the past).
  */
-static int start_dl_timer(struct task_struct *p)
+static int start_dl_timer(struct sched_dl_entity *dl_se)
 {
-	struct sched_dl_entity *dl_se = &p->dl;
 	struct hrtimer *timer = &dl_se->dl_timer;
-	struct rq *rq = task_rq(p);
+	struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
+	struct rq *rq = rq_of_dl_rq(dl_rq);
 	ktime_t now, act;
 	s64 delta;
 
@@ -1056,13 +1080,33 @@ static int start_dl_timer(struct task_struct *p)
 	 * and observe our state.
 	 */
 	if (!hrtimer_is_queued(timer)) {
-		get_task_struct(p);
+		if (!dl_server(dl_se))
+			get_task_struct(dl_task_of(dl_se));
 		hrtimer_start(timer, act, HRTIMER_MODE_ABS_HARD);
 	}
 
 	return 1;
 }
 
+static void __push_dl_task(struct rq *rq, struct rq_flags *rf)
+{
+#ifdef CONFIG_SMP
+	/*
+	 * Queueing this task back might have overloaded rq, check if we need
+	 * to kick someone away.
+	 */
+	if (has_pushable_dl_tasks(rq)) {
+		/*
+		 * Nothing relies on rq->lock after this, so its safe to drop
+		 * rq->lock.
+		 */
+		rq_unpin_lock(rq, rf);
+		push_dl_task(rq);
+		rq_repin_lock(rq, rf);
+	}
+#endif
+}
+
 /*
  * This is the bandwidth enforcement timer callback. If here, we know
  * a task is not on its dl_rq, since the fact that the timer was running
@@ -1081,10 +1125,34 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
 	struct sched_dl_entity *dl_se = container_of(timer,
 						     struct sched_dl_entity,
 						     dl_timer);
-	struct task_struct *p = dl_task_of(dl_se);
+	struct task_struct *p;
 	struct rq_flags rf;
 	struct rq *rq;
 
+	if (dl_server(dl_se)) {
+		struct rq *rq = rq_of_dl_se(dl_se);
+		struct rq_flags rf;
+
+		rq_lock(rq, &rf);
+		if (dl_se->dl_throttled) {
+			sched_clock_tick();
+			update_rq_clock(rq);
+
+			if (dl_se->server_has_tasks(dl_se)) {
+				enqueue_dl_entity(dl_se, ENQUEUE_REPLENISH);
+				resched_curr(rq);
+				__push_dl_task(rq, &rf);
+			} else {
+				replenish_dl_entity(dl_se);
+			}
+
+		}
+		rq_unlock(rq, &rf);
+
+		return HRTIMER_NORESTART;
+	}
+
+	p = dl_task_of(dl_se);
 	rq = task_rq_lock(p, &rf);
 
 	/*
@@ -1155,21 +1223,7 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
 	else
 		resched_curr(rq);
 
-#ifdef CONFIG_SMP
-	/*
-	 * Queueing this task back might have overloaded rq, check if we need
-	 * to kick someone away.
-	 */
-	if (has_pushable_dl_tasks(rq)) {
-		/*
-		 * Nothing relies on rq->lock after this, so its safe to drop
-		 * rq->lock.
-		 */
-		rq_unpin_lock(rq, &rf);
-		push_dl_task(rq);
-		rq_repin_lock(rq, &rf);
-	}
-#endif
+	__push_dl_task(rq, &rf);
 
 unlock:
 	task_rq_unlock(rq, p, &rf);
@@ -1183,7 +1237,7 @@ unlock:
 	return HRTIMER_NORESTART;
 }
 
-void init_dl_task_timer(struct sched_dl_entity *dl_se)
+static void init_dl_task_timer(struct sched_dl_entity *dl_se)
 {
 	struct hrtimer *timer = &dl_se->dl_timer;
 
@@ -1211,12 +1265,11 @@ void init_dl_task_timer(struct sched_dl_entity *dl_se)
  */
 static inline void dl_check_constrained_dl(struct sched_dl_entity *dl_se)
 {
-	struct task_struct *p = dl_task_of(dl_se);
-	struct rq *rq = rq_of_dl_rq(dl_rq_of_se(dl_se));
+	struct rq *rq = rq_of_dl_se(dl_se);
 
 	if (dl_time_before(dl_se->deadline, rq_clock(rq)) &&
 	    dl_time_before(rq_clock(rq), dl_next_period(dl_se))) {
-		if (unlikely(is_dl_boosted(dl_se) || !start_dl_timer(p)))
+		if (unlikely(is_dl_boosted(dl_se) || !start_dl_timer(dl_se)))
 			return;
 		dl_se->dl_throttled = 1;
 		if (dl_se->runtime > 0)
@@ -1267,44 +1320,19 @@ static u64 grub_reclaim(u64 delta, struct rq *rq, struct sched_dl_entity *dl_se)
 	return (delta * u_act) >> BW_SHIFT;
 }
 
-/*
- * Update the current task's runtime statistics (provided it is still
- * a -deadline task and has not been removed from the dl_rq).
- */
-static void update_curr_dl(struct rq *rq)
+static inline void
+update_stats_dequeue_dl(struct dl_rq *dl_rq, struct sched_dl_entity *dl_se,
+                        int flags);
+static void update_curr_dl_se(struct rq *rq, struct sched_dl_entity *dl_se, s64 delta_exec)
 {
-	struct task_struct *curr = rq->curr;
-	struct sched_dl_entity *dl_se = &curr->dl;
-	u64 delta_exec, scaled_delta_exec;
-	int cpu = cpu_of(rq);
-	u64 now;
-
-	if (!dl_task(curr) || !on_dl_rq(dl_se))
-		return;
+	s64 scaled_delta_exec;
 
-	/*
-	 * Consumed budget is computed considering the time as
-	 * observed by schedulable tasks (excluding time spent
-	 * in hardirq context, etc.). Deadlines are instead
-	 * computed using hard walltime. This seems to be the more
-	 * natural solution, but the full ramifications of this
-	 * approach need further study.
-	 */
-	now = rq_clock_task(rq);
-	delta_exec = now - curr->se.exec_start;
-	if (unlikely((s64)delta_exec <= 0)) {
+	if (unlikely(delta_exec <= 0)) {
 		if (unlikely(dl_se->dl_yielded))
 			goto throttle;
 		return;
 	}
 
-	schedstat_set(curr->stats.exec_max,
-		      max(curr->stats.exec_max, delta_exec));
-
-	trace_sched_stat_runtime(curr, delta_exec, 0);
-
-	update_current_exec_runtime(curr, now, delta_exec);
-
 	if (dl_entity_is_special(dl_se))
 		return;
 
@@ -1316,10 +1344,9 @@ static void update_curr_dl(struct rq *rq)
 	 * according to current frequency and CPU maximum capacity.
 	 */
 	if (unlikely(dl_se->flags & SCHED_FLAG_RECLAIM)) {
-		scaled_delta_exec = grub_reclaim(delta_exec,
-						 rq,
-						 &curr->dl);
+		scaled_delta_exec = grub_reclaim(delta_exec, rq, dl_se);
 	} else {
+		int cpu = cpu_of(rq);
 		unsigned long scale_freq = arch_scale_freq_capacity(cpu);
 		unsigned long scale_cpu = arch_scale_cpu_capacity(cpu);
 
@@ -1338,11 +1365,20 @@ throttle:
 		    (dl_se->flags & SCHED_FLAG_DL_OVERRUN))
 			dl_se->dl_overrun = 1;
 
-		__dequeue_task_dl(rq, curr, 0);
-		if (unlikely(is_dl_boosted(dl_se) || !start_dl_timer(curr)))
-			enqueue_task_dl(rq, curr, ENQUEUE_REPLENISH);
+		dequeue_dl_entity(dl_se, 0);
+		if (!dl_server(dl_se)) {
+			update_stats_dequeue_dl(&rq->dl, dl_se, 0);
+			dequeue_pushable_dl_task(rq, dl_task_of(dl_se));
+		}
+
+		if (unlikely(is_dl_boosted(dl_se) || !start_dl_timer(dl_se))) {
+			if (dl_server(dl_se))
+				enqueue_dl_entity(dl_se, ENQUEUE_REPLENISH);
+			else
+				enqueue_task_dl(rq, dl_task_of(dl_se), ENQUEUE_REPLENISH);
+		}
 
-		if (!is_leftmost(curr, &rq->dl))
+		if (!is_leftmost(dl_se, &rq->dl))
 			resched_curr(rq);
 	}
 
@@ -1372,20 +1408,82 @@ throttle:
 	}
 }
 
+void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec)
+{
+	update_curr_dl_se(dl_se->rq, dl_se, delta_exec);
+}
+
+void dl_server_start(struct sched_dl_entity *dl_se)
+{
+	if (!dl_server(dl_se)) {
+		dl_se->dl_server = 1;
+		setup_new_dl_entity(dl_se);
+	}
+	enqueue_dl_entity(dl_se, ENQUEUE_WAKEUP);
+}
+
+void dl_server_stop(struct sched_dl_entity *dl_se)
+{
+	dequeue_dl_entity(dl_se, DEQUEUE_SLEEP);
+}
+
+void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq,
+		    dl_server_has_tasks_f has_tasks,
+		    dl_server_pick_f pick)
+{
+	dl_se->rq = rq;
+	dl_se->server_has_tasks = has_tasks;
+	dl_se->server_pick = pick;
+}
+
+/*
+ * Update the current task's runtime statistics (provided it is still
+ * a -deadline task and has not been removed from the dl_rq).
+ */
+static void update_curr_dl(struct rq *rq)
+{
+	struct task_struct *curr = rq->curr;
+	struct sched_dl_entity *dl_se = &curr->dl;
+	s64 delta_exec;
+
+	if (!dl_task(curr) || !on_dl_rq(dl_se))
+		return;
+
+	/*
+	 * Consumed budget is computed considering the time as
+	 * observed by schedulable tasks (excluding time spent
+	 * in hardirq context, etc.). Deadlines are instead
+	 * computed using hard walltime. This seems to be the more
+	 * natural solution, but the full ramifications of this
+	 * approach need further study.
+	 */
+	delta_exec = update_curr_common(rq);
+	update_curr_dl_se(rq, dl_se, delta_exec);
+}
+
 static enum hrtimer_restart inactive_task_timer(struct hrtimer *timer)
 {
 	struct sched_dl_entity *dl_se = container_of(timer,
 						     struct sched_dl_entity,
 						     inactive_timer);
-	struct task_struct *p = dl_task_of(dl_se);
+	struct task_struct *p = NULL;
 	struct rq_flags rf;
 	struct rq *rq;
 
-	rq = task_rq_lock(p, &rf);
+	if (!dl_server(dl_se)) {
+		p = dl_task_of(dl_se);
+		rq = task_rq_lock(p, &rf);
+	} else {
+		rq = dl_se->rq;
+		rq_lock(rq, &rf);
+	}
 
 	sched_clock_tick();
 	update_rq_clock(rq);
 
+	if (dl_server(dl_se))
+		goto no_task;
+
 	if (!dl_task(p) || READ_ONCE(p->__state) == TASK_DEAD) {
 		struct dl_bw *dl_b = dl_bw_of(task_cpu(p));
 
@@ -1398,23 +1496,30 @@ static enum hrtimer_restart inactive_task_timer(struct hrtimer *timer)
 		raw_spin_lock(&dl_b->lock);
 		__dl_sub(dl_b, p->dl.dl_bw, dl_bw_cpus(task_cpu(p)));
 		raw_spin_unlock(&dl_b->lock);
-		__dl_clear_params(p);
+		__dl_clear_params(dl_se);
 
 		goto unlock;
 	}
+
+no_task:
 	if (dl_se->dl_non_contending == 0)
 		goto unlock;
 
 	sub_running_bw(dl_se, &rq->dl);
 	dl_se->dl_non_contending = 0;
 unlock:
-	task_rq_unlock(rq, p, &rf);
-	put_task_struct(p);
+
+	if (!dl_server(dl_se)) {
+		task_rq_unlock(rq, p, &rf);
+		put_task_struct(p);
+	} else {
+		rq_unlock(rq, &rf);
+	}
 
 	return HRTIMER_NORESTART;
 }
 
-void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se)
+static void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se)
 {
 	struct hrtimer *timer = &dl_se->inactive_timer;
 
@@ -1472,10 +1577,8 @@ static inline void dec_dl_deadline(struct dl_rq *dl_rq, u64 deadline) {}
 static inline
 void inc_dl_tasks(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
 {
-	int prio = dl_task_of(dl_se)->prio;
 	u64 deadline = dl_se->deadline;
 
-	WARN_ON(!dl_prio(prio));
 	dl_rq->dl_nr_running++;
 	add_nr_running(rq_of_dl_rq(dl_rq), 1);
 
@@ -1485,9 +1588,6 @@ void inc_dl_tasks(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
 static inline
 void dec_dl_tasks(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq)
 {
-	int prio = dl_task_of(dl_se)->prio;
-
-	WARN_ON(!dl_prio(prio));
 	WARN_ON(!dl_rq->dl_nr_running);
 	dl_rq->dl_nr_running--;
 	sub_nr_running(rq_of_dl_rq(dl_rq), 1);
@@ -1609,6 +1709,41 @@ enqueue_dl_entity(struct sched_dl_entity *dl_se, int flags)
 	update_stats_enqueue_dl(dl_rq_of_se(dl_se), dl_se, flags);
 
 	/*
+	 * Check if a constrained deadline task was activated
+	 * after the deadline but before the next period.
+	 * If that is the case, the task will be throttled and
+	 * the replenishment timer will be set to the next period.
+	 */
+	if (!dl_se->dl_throttled && !dl_is_implicit(dl_se))
+		dl_check_constrained_dl(dl_se);
+
+	if (flags & (ENQUEUE_RESTORE|ENQUEUE_MIGRATING)) {
+		struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
+
+		add_rq_bw(dl_se, dl_rq);
+		add_running_bw(dl_se, dl_rq);
+	}
+
+	/*
+	 * If p is throttled, we do not enqueue it. In fact, if it exhausted
+	 * its budget it needs a replenishment and, since it now is on
+	 * its rq, the bandwidth timer callback (which clearly has not
+	 * run yet) will take care of this.
+	 * However, the active utilization does not depend on the fact
+	 * that the task is on the runqueue or not (but depends on the
+	 * task's state - in GRUB parlance, "inactive" vs "active contending").
+	 * In other words, even if a task is throttled its utilization must
+	 * be counted in the active utilization; hence, we need to call
+	 * add_running_bw().
+	 */
+	if (dl_se->dl_throttled && !(flags & ENQUEUE_REPLENISH)) {
+		if (flags & ENQUEUE_WAKEUP)
+			task_contending(dl_se, flags);
+
+		return;
+	}
+
+	/*
 	 * If this is a wakeup or a new instance, the scheduling
 	 * parameters of the task might need updating. Otherwise,
 	 * we want a replenishment of its runtime.
@@ -1619,17 +1754,35 @@ enqueue_dl_entity(struct sched_dl_entity *dl_se, int flags)
 	} else if (flags & ENQUEUE_REPLENISH) {
 		replenish_dl_entity(dl_se);
 	} else if ((flags & ENQUEUE_RESTORE) &&
-		  dl_time_before(dl_se->deadline,
-				 rq_clock(rq_of_dl_rq(dl_rq_of_se(dl_se))))) {
+		   dl_time_before(dl_se->deadline, rq_clock(rq_of_dl_se(dl_se)))) {
 		setup_new_dl_entity(dl_se);
 	}
 
 	__enqueue_dl_entity(dl_se);
 }
 
-static void dequeue_dl_entity(struct sched_dl_entity *dl_se)
+static void dequeue_dl_entity(struct sched_dl_entity *dl_se, int flags)
 {
 	__dequeue_dl_entity(dl_se);
+
+	if (flags & (DEQUEUE_SAVE|DEQUEUE_MIGRATING)) {
+		struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
+
+		sub_running_bw(dl_se, dl_rq);
+		sub_rq_bw(dl_se, dl_rq);
+	}
+
+	/*
+	 * This check allows to start the inactive timer (or to immediately
+	 * decrease the active utilization, if needed) in two cases:
+	 * when the task blocks and when it is terminating
+	 * (p->state == TASK_DEAD). We can handle the two cases in the same
+	 * way, because from GRUB's point of view the same thing is happening
+	 * (the task moves from "active contending" to "active non contending"
+	 * or "inactive")
+	 */
+	if (flags & DEQUEUE_SLEEP)
+		task_non_contending(dl_se);
 }
 
 static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags)
@@ -1674,76 +1827,31 @@ static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags)
 		return;
 	}
 
-	/*
-	 * Check if a constrained deadline task was activated
-	 * after the deadline but before the next period.
-	 * If that is the case, the task will be throttled and
-	 * the replenishment timer will be set to the next period.
-	 */
-	if (!p->dl.dl_throttled && !dl_is_implicit(&p->dl))
-		dl_check_constrained_dl(&p->dl);
-
-	if (p->on_rq == TASK_ON_RQ_MIGRATING || flags & ENQUEUE_RESTORE) {
-		add_rq_bw(&p->dl, &rq->dl);
-		add_running_bw(&p->dl, &rq->dl);
-	}
-
-	/*
-	 * If p is throttled, we do not enqueue it. In fact, if it exhausted
-	 * its budget it needs a replenishment and, since it now is on
-	 * its rq, the bandwidth timer callback (which clearly has not
-	 * run yet) will take care of this.
-	 * However, the active utilization does not depend on the fact
-	 * that the task is on the runqueue or not (but depends on the
-	 * task's state - in GRUB parlance, "inactive" vs "active contending").
-	 * In other words, even if a task is throttled its utilization must
-	 * be counted in the active utilization; hence, we need to call
-	 * add_running_bw().
-	 */
-	if (p->dl.dl_throttled && !(flags & ENQUEUE_REPLENISH)) {
-		if (flags & ENQUEUE_WAKEUP)
-			task_contending(&p->dl, flags);
-
-		return;
-	}
-
 	check_schedstat_required();
 	update_stats_wait_start_dl(dl_rq_of_se(&p->dl), &p->dl);
 
+	if (p->on_rq == TASK_ON_RQ_MIGRATING)
+		flags |= ENQUEUE_MIGRATING;
+
 	enqueue_dl_entity(&p->dl, flags);
 
-	if (!task_current(rq, p) && p->nr_cpus_allowed > 1)
-		enqueue_pushable_dl_task(rq, p);
-}
+	if (dl_server(&p->dl))
+		return;
 
-static void __dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags)
-{
-	update_stats_dequeue_dl(&rq->dl, &p->dl, flags);
-	dequeue_dl_entity(&p->dl);
-	dequeue_pushable_dl_task(rq, p);
+	if (!task_current(rq, p) && !p->dl.dl_throttled && p->nr_cpus_allowed > 1)
+		enqueue_pushable_dl_task(rq, p);
 }
 
 static void dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags)
 {
 	update_curr_dl(rq);
-	__dequeue_task_dl(rq, p, flags);
 
-	if (p->on_rq == TASK_ON_RQ_MIGRATING || flags & DEQUEUE_SAVE) {
-		sub_running_bw(&p->dl, &rq->dl);
-		sub_rq_bw(&p->dl, &rq->dl);
-	}
+	if (p->on_rq == TASK_ON_RQ_MIGRATING)
+		flags |= DEQUEUE_MIGRATING;
 
-	/*
-	 * This check allows to start the inactive timer (or to immediately
-	 * decrease the active utilization, if needed) in two cases:
-	 * when the task blocks and when it is terminating
-	 * (p->state == TASK_DEAD). We can handle the two cases in the same
-	 * way, because from GRUB's point of view the same thing is happening
-	 * (the task moves from "active contending" to "active non contending"
-	 * or "inactive")
-	 */
-	if (flags & DEQUEUE_SLEEP)
-		task_non_contending(p);
+	dequeue_dl_entity(&p->dl, flags);
+	if (!p->dl.dl_throttled && !dl_server(&p->dl))
+		dequeue_pushable_dl_task(rq, p);
 }
 
 /*
@@ -1933,12 +2041,12 @@ static void wakeup_preempt_dl(struct rq *rq, struct task_struct *p,
 }
 
 #ifdef CONFIG_SCHED_HRTICK
-static void start_hrtick_dl(struct rq *rq, struct task_struct *p)
+static void start_hrtick_dl(struct rq *rq, struct sched_dl_entity *dl_se)
 {
-	hrtick_start(rq, p->dl.runtime);
+	hrtick_start(rq, dl_se->runtime);
 }
 #else /* !CONFIG_SCHED_HRTICK */
-static void start_hrtick_dl(struct rq *rq, struct task_struct *p)
+static void start_hrtick_dl(struct rq *rq, struct sched_dl_entity *dl_se)
 {
 }
 #endif
@@ -1958,9 +2066,6 @@ static void set_next_task_dl(struct rq *rq, struct task_struct *p, bool first)
 	if (!first)
 		return;
 
-	if (hrtick_enabled_dl(rq))
-		start_hrtick_dl(rq, p);
-
 	if (rq->curr->sched_class != &dl_sched_class)
 		update_dl_rq_load_avg(rq_clock_pelt(rq), rq, 0);
 
@@ -1983,12 +2088,25 @@ static struct task_struct *pick_task_dl(struct rq *rq)
 	struct dl_rq *dl_rq = &rq->dl;
 	struct task_struct *p;
 
+again:
 	if (!sched_dl_runnable(rq))
 		return NULL;
 
 	dl_se = pick_next_dl_entity(dl_rq);
 	WARN_ON_ONCE(!dl_se);
-	p = dl_task_of(dl_se);
+
+	if (dl_server(dl_se)) {
+		p = dl_se->server_pick(dl_se);
+		if (!p) {
+			WARN_ON_ONCE(1);
+			dl_se->dl_yielded = 1;
+			update_curr_dl_se(rq, dl_se, 0);
+			goto again;
+		}
+		p->dl_server = dl_se;
+	} else {
+		p = dl_task_of(dl_se);
+	}
 
 	return p;
 }
@@ -1998,9 +2116,15 @@ static struct task_struct *pick_next_task_dl(struct rq *rq)
 	struct task_struct *p;
 
 	p = pick_task_dl(rq);
-	if (p)
+	if (!p)
+		return p;
+
+	if (!p->dl_server)
 		set_next_task_dl(rq, p, true);
 
+	if (hrtick_enabled(rq))
+		start_hrtick_dl(rq, &p->dl);
+
 	return p;
 }
 
@@ -2038,8 +2162,8 @@ static void task_tick_dl(struct rq *rq, struct task_struct *p, int queued)
 	 * be set and schedule() will start a new hrtick for the next task.
 	 */
 	if (hrtick_enabled_dl(rq) && queued && p->dl.runtime > 0 &&
-	    is_leftmost(p, &rq->dl))
-		start_hrtick_dl(rq, p);
+	    is_leftmost(&p->dl, &rq->dl))
+		start_hrtick_dl(rq, &p->dl);
 }
 
 static void task_fork_dl(struct task_struct *p)
@@ -2558,7 +2682,7 @@ static void switched_from_dl(struct rq *rq, struct task_struct *p)
 	 * will reset the task parameters.
 	 */
 	if (task_on_rq_queued(p) && p->dl.dl_runtime)
-		task_non_contending(p);
+		task_non_contending(&p->dl);
 
 	/*
 	 * In case a task is setscheduled out from SCHED_DEADLINE we need to
@@ -2966,10 +3090,8 @@ bool __checkparam_dl(const struct sched_attr *attr)
 /*
  * This function clears the sched_dl_entity static params.
  */
-void __dl_clear_params(struct task_struct *p)
+static void __dl_clear_params(struct sched_dl_entity *dl_se)
 {
-	struct sched_dl_entity *dl_se = &p->dl;
-
 	dl_se->dl_runtime		= 0;
 	dl_se->dl_deadline		= 0;
 	dl_se->dl_period		= 0;
@@ -2981,12 +3103,21 @@ void __dl_clear_params(struct task_struct *p)
 	dl_se->dl_yielded		= 0;
 	dl_se->dl_non_contending	= 0;
 	dl_se->dl_overrun		= 0;
+	dl_se->dl_server		= 0;
 
 #ifdef CONFIG_RT_MUTEXES
 	dl_se->pi_se			= dl_se;
 #endif
 }
 
+void init_dl_entity(struct sched_dl_entity *dl_se)
+{
+	RB_CLEAR_NODE(&dl_se->rb_node);
+	init_dl_task_timer(dl_se);
+	init_dl_inactive_task_timer(dl_se);
+	__dl_clear_params(dl_se);
+}
+
 bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr)
 {
 	struct sched_dl_entity *dl_se = &p->dl;
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 4580a45070..8d5d98a583 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -628,8 +628,8 @@ static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
 
 void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 {
-	s64 left_vruntime = -1, min_vruntime, right_vruntime = -1, spread;
-	struct sched_entity *last, *first;
+	s64 left_vruntime = -1, min_vruntime, right_vruntime = -1, left_deadline = -1, spread;
+	struct sched_entity *last, *first, *root;
 	struct rq *rq = cpu_rq(cpu);
 	unsigned long flags;
 
@@ -644,15 +644,20 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 			SPLIT_NS(cfs_rq->exec_clock));
 
 	raw_spin_rq_lock_irqsave(rq, flags);
+	root = __pick_root_entity(cfs_rq);
+	if (root)
+		left_vruntime = root->min_vruntime;
 	first = __pick_first_entity(cfs_rq);
 	if (first)
-		left_vruntime = first->vruntime;
+		left_deadline = first->deadline;
 	last = __pick_last_entity(cfs_rq);
 	if (last)
 		right_vruntime = last->vruntime;
 	min_vruntime = cfs_rq->min_vruntime;
 	raw_spin_rq_unlock_irqrestore(rq, flags);
 
+	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "left_deadline",
+			SPLIT_NS(left_deadline));
 	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "left_vruntime",
 			SPLIT_NS(left_vruntime));
 	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "min_vruntime",
@@ -679,8 +684,8 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 			cfs_rq->avg.runnable_avg);
 	SEQ_printf(m, "  .%-30s: %lu\n", "util_avg",
 			cfs_rq->avg.util_avg);
-	SEQ_printf(m, "  .%-30s: %u\n", "util_est_enqueued",
-			cfs_rq->avg.util_est.enqueued);
+	SEQ_printf(m, "  .%-30s: %u\n", "util_est",
+			cfs_rq->avg.util_est);
 	SEQ_printf(m, "  .%-30s: %ld\n", "removed.load_avg",
 			cfs_rq->removed.load_avg);
 	SEQ_printf(m, "  .%-30s: %ld\n", "removed.util_avg",
@@ -1070,8 +1075,7 @@ void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns,
 	P(se.avg.runnable_avg);
 	P(se.avg.util_avg);
 	P(se.avg.last_update_time);
-	P(se.avg.util_est.ewma);
-	PM(se.avg.util_est.enqueued, ~UTIL_AVG_UNCHANGED);
+	PM(se.avg.util_est, ~UTIL_AVG_UNCHANGED);
 #endif
 #ifdef CONFIG_UCLAMP_TASK
 	__PS("uclamp.min", p->uclamp_req[UCLAMP_MIN].value);
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index c43b71792a..aee5e7a701 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -551,7 +551,11 @@ static inline u64 min_vruntime(u64 min_vruntime, u64 vruntime)
 static inline bool entity_before(const struct sched_entity *a,
 				 const struct sched_entity *b)
 {
-	return (s64)(a->vruntime - b->vruntime) < 0;
+	/*
+	 * Tiebreak on vruntime seems unnecessary since it can
+	 * hardly happen.
+	 */
+	return (s64)(a->deadline - b->deadline) < 0;
 }
 
 static inline s64 entity_key(struct cfs_rq *cfs_rq, struct sched_entity *se)
@@ -692,15 +696,21 @@ u64 avg_vruntime(struct cfs_rq *cfs_rq)
  *
  * XXX could add max_slice to the augmented data to track this.
  */
-static void update_entity_lag(struct cfs_rq *cfs_rq, struct sched_entity *se)
+static s64 entity_lag(u64 avruntime, struct sched_entity *se)
 {
-	s64 lag, limit;
+	s64 vlag, limit;
+
+	vlag = avruntime - se->vruntime;
+	limit = calc_delta_fair(max_t(u64, 2*se->slice, TICK_NSEC), se);
 
+	return clamp(vlag, -limit, limit);
+}
+
+static void update_entity_lag(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
 	SCHED_WARN_ON(!se->on_rq);
-	lag = avg_vruntime(cfs_rq) - se->vruntime;
 
-	limit = calc_delta_fair(max_t(u64, 2*se->slice, TICK_NSEC), se);
-	se->vlag = clamp(lag, -limit, limit);
+	se->vlag = entity_lag(avg_vruntime(cfs_rq), se);
 }
 
 /*
@@ -720,7 +730,7 @@ static void update_entity_lag(struct cfs_rq *cfs_rq, struct sched_entity *se)
  * Note: using 'avg_vruntime() > se->vruntime' is inacurate due
  *       to the loss in precision caused by the division.
  */
-int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se)
+static int vruntime_eligible(struct cfs_rq *cfs_rq, u64 vruntime)
 {
 	struct sched_entity *curr = cfs_rq->curr;
 	s64 avg = cfs_rq->avg_vruntime;
@@ -733,7 +743,12 @@ int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se)
 		load += weight;
 	}
 
-	return avg >= entity_key(cfs_rq, se) * load;
+	return avg >= (s64)(vruntime - cfs_rq->min_vruntime) * load;
+}
+
+int entity_eligible(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+	return vruntime_eligible(cfs_rq, se->vruntime);
 }
 
 static u64 __update_min_vruntime(struct cfs_rq *cfs_rq, u64 vruntime)
@@ -752,9 +767,8 @@ static u64 __update_min_vruntime(struct cfs_rq *cfs_rq, u64 vruntime)
 
 static void update_min_vruntime(struct cfs_rq *cfs_rq)
 {
-	struct sched_entity *se = __pick_first_entity(cfs_rq);
+	struct sched_entity *se = __pick_root_entity(cfs_rq);
 	struct sched_entity *curr = cfs_rq->curr;
-
 	u64 vruntime = cfs_rq->min_vruntime;
 
 	if (curr) {
@@ -766,9 +780,9 @@ static void update_min_vruntime(struct cfs_rq *cfs_rq)
 
 	if (se) {
 		if (!curr)
-			vruntime = se->vruntime;
+			vruntime = se->min_vruntime;
 		else
-			vruntime = min_vruntime(vruntime, se->vruntime);
+			vruntime = min_vruntime(vruntime, se->min_vruntime);
 	}
 
 	/* ensure we never gain time by being placed backwards. */
@@ -781,34 +795,34 @@ static inline bool __entity_less(struct rb_node *a, const struct rb_node *b)
 	return entity_before(__node_2_se(a), __node_2_se(b));
 }
 
-#define deadline_gt(field, lse, rse) ({ (s64)((lse)->field - (rse)->field) > 0; })
+#define vruntime_gt(field, lse, rse) ({ (s64)((lse)->field - (rse)->field) > 0; })
 
-static inline void __update_min_deadline(struct sched_entity *se, struct rb_node *node)
+static inline void __min_vruntime_update(struct sched_entity *se, struct rb_node *node)
 {
 	if (node) {
 		struct sched_entity *rse = __node_2_se(node);
-		if (deadline_gt(min_deadline, se, rse))
-			se->min_deadline = rse->min_deadline;
+		if (vruntime_gt(min_vruntime, se, rse))
+			se->min_vruntime = rse->min_vruntime;
 	}
 }
 
 /*
- * se->min_deadline = min(se->deadline, left->min_deadline, right->min_deadline)
+ * se->min_vruntime = min(se->vruntime, {left,right}->min_vruntime)
  */
-static inline bool min_deadline_update(struct sched_entity *se, bool exit)
+static inline bool min_vruntime_update(struct sched_entity *se, bool exit)
 {
-	u64 old_min_deadline = se->min_deadline;
+	u64 old_min_vruntime = se->min_vruntime;
 	struct rb_node *node = &se->run_node;
 
-	se->min_deadline = se->deadline;
-	__update_min_deadline(se, node->rb_right);
-	__update_min_deadline(se, node->rb_left);
+	se->min_vruntime = se->vruntime;
+	__min_vruntime_update(se, node->rb_right);
+	__min_vruntime_update(se, node->rb_left);
 
-	return se->min_deadline == old_min_deadline;
+	return se->min_vruntime == old_min_vruntime;
 }
 
-RB_DECLARE_CALLBACKS(static, min_deadline_cb, struct sched_entity,
-		     run_node, min_deadline, min_deadline_update);
+RB_DECLARE_CALLBACKS(static, min_vruntime_cb, struct sched_entity,
+		     run_node, min_vruntime, min_vruntime_update);
 
 /*
  * Enqueue an entity into the rb-tree:
@@ -816,18 +830,28 @@ RB_DECLARE_CALLBACKS(static, min_deadline_cb, struct sched_entity,
 static void __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
 	avg_vruntime_add(cfs_rq, se);
-	se->min_deadline = se->deadline;
+	se->min_vruntime = se->vruntime;
 	rb_add_augmented_cached(&se->run_node, &cfs_rq->tasks_timeline,
-				__entity_less, &min_deadline_cb);
+				__entity_less, &min_vruntime_cb);
 }
 
 static void __dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
 {
 	rb_erase_augmented_cached(&se->run_node, &cfs_rq->tasks_timeline,
-				  &min_deadline_cb);
+				  &min_vruntime_cb);
 	avg_vruntime_sub(cfs_rq, se);
 }
 
+struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq)
+{
+	struct rb_node *root = cfs_rq->tasks_timeline.rb_root.rb_node;
+
+	if (!root)
+		return NULL;
+
+	return __node_2_se(root);
+}
+
 struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq)
 {
 	struct rb_node *left = rb_first_cached(&cfs_rq->tasks_timeline);
@@ -850,23 +874,29 @@ struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq)
  *     with the earliest virtual deadline.
  *
  * We can do this in O(log n) time due to an augmented RB-tree. The
- * tree keeps the entries sorted on service, but also functions as a
- * heap based on the deadline by keeping:
+ * tree keeps the entries sorted on deadline, but also functions as a
+ * heap based on the vruntime by keeping:
  *
- *  se->min_deadline = min(se->deadline, se->{left,right}->min_deadline)
+ *  se->min_vruntime = min(se->vruntime, se->{left,right}->min_vruntime)
  *
- * Which allows an EDF like search on (sub)trees.
+ * Which allows tree pruning through eligibility.
  */
-static struct sched_entity *__pick_eevdf(struct cfs_rq *cfs_rq)
+static struct sched_entity *pick_eevdf(struct cfs_rq *cfs_rq)
 {
 	struct rb_node *node = cfs_rq->tasks_timeline.rb_root.rb_node;
+	struct sched_entity *se = __pick_first_entity(cfs_rq);
 	struct sched_entity *curr = cfs_rq->curr;
 	struct sched_entity *best = NULL;
-	struct sched_entity *best_left = NULL;
+
+	/*
+	 * We can safely skip eligibility check if there is only one entity
+	 * in this cfs_rq, saving some cycles.
+	 */
+	if (cfs_rq->nr_running == 1)
+		return curr && curr->on_rq ? curr : se;
 
 	if (curr && (!curr->on_rq || !entity_eligible(cfs_rq, curr)))
 		curr = NULL;
-	best = curr;
 
 	/*
 	 * Once selected, run a task until it either becomes non-eligible or
@@ -875,95 +905,45 @@ static struct sched_entity *__pick_eevdf(struct cfs_rq *cfs_rq)
 	if (sched_feat(RUN_TO_PARITY) && curr && curr->vlag == curr->deadline)
 		return curr;
 
+	/* Pick the leftmost entity if it's eligible */
+	if (se && entity_eligible(cfs_rq, se)) {
+		best = se;
+		goto found;
+	}
+
+	/* Heap search for the EEVD entity */
 	while (node) {
-		struct sched_entity *se = __node_2_se(node);
+		struct rb_node *left = node->rb_left;
 
 		/*
-		 * If this entity is not eligible, try the left subtree.
+		 * Eligible entities in left subtree are always better
+		 * choices, since they have earlier deadlines.
 		 */
-		if (!entity_eligible(cfs_rq, se)) {
-			node = node->rb_left;
+		if (left && vruntime_eligible(cfs_rq,
+					__node_2_se(left)->min_vruntime)) {
+			node = left;
 			continue;
 		}
 
-		/*
-		 * Now we heap search eligible trees for the best (min_)deadline
-		 */
-		if (!best || deadline_gt(deadline, best, se))
-			best = se;
+		se = __node_2_se(node);
 
 		/*
-		 * Every se in a left branch is eligible, keep track of the
-		 * branch with the best min_deadline
+		 * The left subtree either is empty or has no eligible
+		 * entity, so check the current node since it is the one
+		 * with earliest deadline that might be eligible.
 		 */
-		if (node->rb_left) {
-			struct sched_entity *left = __node_2_se(node->rb_left);
-
-			if (!best_left || deadline_gt(min_deadline, best_left, left))
-				best_left = left;
-
-			/*
-			 * min_deadline is in the left branch. rb_left and all
-			 * descendants are eligible, so immediately switch to the second
-			 * loop.
-			 */
-			if (left->min_deadline == se->min_deadline)
-				break;
-		}
-
-		/* min_deadline is at this node, no need to look right */
-		if (se->deadline == se->min_deadline)
+		if (entity_eligible(cfs_rq, se)) {
+			best = se;
 			break;
-
-		/* else min_deadline is in the right branch. */
-		node = node->rb_right;
-	}
-
-	/*
-	 * We ran into an eligible node which is itself the best.
-	 * (Or nr_running == 0 and both are NULL)
-	 */
-	if (!best_left || (s64)(best_left->min_deadline - best->deadline) > 0)
-		return best;
-
-	/*
-	 * Now best_left and all of its children are eligible, and we are just
-	 * looking for deadline == min_deadline
-	 */
-	node = &best_left->run_node;
-	while (node) {
-		struct sched_entity *se = __node_2_se(node);
-
-		/* min_deadline is the current node */
-		if (se->deadline == se->min_deadline)
-			return se;
-
-		/* min_deadline is in the left branch */
-		if (node->rb_left &&
-		    __node_2_se(node->rb_left)->min_deadline == se->min_deadline) {
-			node = node->rb_left;
-			continue;
 		}
 
-		/* else min_deadline is in the right branch */
 		node = node->rb_right;
 	}
-	return NULL;
-}
-
-static struct sched_entity *pick_eevdf(struct cfs_rq *cfs_rq)
-{
-	struct sched_entity *se = __pick_eevdf(cfs_rq);
-
-	if (!se) {
-		struct sched_entity *left = __pick_first_entity(cfs_rq);
-		if (left) {
-			pr_err("EEVDF scheduling fail, picking leftmost\n");
-			return left;
-		}
-	}
+found:
+	if (!best || (curr && entity_before(curr, best)))
+		best = curr;
 
-	return se;
+	return best;
 }
 
 #ifdef CONFIG_SCHED_DEBUG
@@ -1129,23 +1109,17 @@ static void update_tg_load_avg(struct cfs_rq *cfs_rq)
 }
 #endif /* CONFIG_SMP */
 
-/*
- * Update the current task's runtime statistics.
- */
-static void update_curr(struct cfs_rq *cfs_rq)
+static s64 update_curr_se(struct rq *rq, struct sched_entity *curr)
 {
-	struct sched_entity *curr = cfs_rq->curr;
-	u64 now = rq_clock_task(rq_of(cfs_rq));
-	u64 delta_exec;
-
-	if (unlikely(!curr))
-		return;
+	u64 now = rq_clock_task(rq);
+	s64 delta_exec;
 
 	delta_exec = now - curr->exec_start;
-	if (unlikely((s64)delta_exec <= 0))
-		return;
+	if (unlikely(delta_exec <= 0))
+		return delta_exec;
 
 	curr->exec_start = now;
+	curr->sum_exec_runtime += delta_exec;
 
 	if (schedstat_enabled()) {
 		struct sched_statistics *stats;
@@ -1155,20 +1129,54 @@ static void update_curr(struct cfs_rq *cfs_rq)
 				max(delta_exec, stats->exec_max));
 	}
 
-	curr->sum_exec_runtime += delta_exec;
-	schedstat_add(cfs_rq->exec_clock, delta_exec);
+	return delta_exec;
+}
+
+static inline void update_curr_task(struct task_struct *p, s64 delta_exec)
+{
+	trace_sched_stat_runtime(p, delta_exec);
+	account_group_exec_runtime(p, delta_exec);
+	cgroup_account_cputime(p, delta_exec);
+	if (p->dl_server)
+		dl_server_update(p->dl_server, delta_exec);
+}
+
+/*
+ * Used by other classes to account runtime.
+ */
+s64 update_curr_common(struct rq *rq)
+{
+	struct task_struct *curr = rq->curr;
+	s64 delta_exec;
+
+	delta_exec = update_curr_se(rq, &curr->se);
+	if (likely(delta_exec > 0))
+		update_curr_task(curr, delta_exec);
+
+	return delta_exec;
+}
+
+/*
+ * Update the current task's runtime statistics.
+ */
+static void update_curr(struct cfs_rq *cfs_rq)
+{
+	struct sched_entity *curr = cfs_rq->curr;
+	s64 delta_exec;
+
+	if (unlikely(!curr))
+		return;
+
+	delta_exec = update_curr_se(rq_of(cfs_rq), curr);
+	if (unlikely(delta_exec <= 0))
+		return;
 
 	curr->vruntime += calc_delta_fair(delta_exec, curr);
 	update_deadline(cfs_rq, curr);
 	update_min_vruntime(cfs_rq);
 
-	if (entity_is_task(curr)) {
-		struct task_struct *curtask = task_of(curr);
-
-		trace_sched_stat_runtime(curtask, delta_exec, curr->vruntime);
-		cgroup_account_cputime(curtask, delta_exec);
-		account_group_exec_runtime(curtask, delta_exec);
-	}
+	if (entity_is_task(curr))
+		update_curr_task(task_of(curr), delta_exec);
 
 	account_cfs_rq_runtime(cfs_rq, delta_exec);
 }
@@ -3668,11 +3676,10 @@ static inline void
 dequeue_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) { }
 #endif
 
-static void reweight_eevdf(struct cfs_rq *cfs_rq, struct sched_entity *se,
+static void reweight_eevdf(struct sched_entity *se, u64 avruntime,
 			   unsigned long weight)
 {
 	unsigned long old_weight = se->load.weight;
-	u64 avruntime = avg_vruntime(cfs_rq);
 	s64 vlag, vslice;
 
 	/*
@@ -3753,7 +3760,7 @@ static void reweight_eevdf(struct cfs_rq *cfs_rq, struct sched_entity *se,
 	 *	   = V  - vl'
 	 */
 	if (avruntime != se->vruntime) {
-		vlag = (s64)(avruntime - se->vruntime);
+		vlag = entity_lag(avruntime, se);
 		vlag = div_s64(vlag * old_weight, weight);
 		se->vruntime = avruntime - vlag;
 	}
@@ -3779,25 +3786,26 @@ static void reweight_entity(struct cfs_rq *cfs_rq, struct sched_entity *se,
 			    unsigned long weight)
 {
 	bool curr = cfs_rq->curr == se;
+	u64 avruntime;
 
 	if (se->on_rq) {
 		/* commit outstanding execution time */
-		if (curr)
-			update_curr(cfs_rq);
-		else
+		update_curr(cfs_rq);
+		avruntime = avg_vruntime(cfs_rq);
+		if (!curr)
 			__dequeue_entity(cfs_rq, se);
 		update_load_sub(&cfs_rq->load, se->load.weight);
 	}
 	dequeue_load_avg(cfs_rq, se);
 
-	if (!se->on_rq) {
+	if (se->on_rq) {
+		reweight_eevdf(se, avruntime, weight);
+	} else {
 		/*
 		 * Because we keep se->vlag = V - v_i, while: lag_i = w_i*(V - v_i),
 		 * we need to scale se->vlag when w_i changes.
 		 */
 		se->vlag = div_s64(se->vlag * se->load.weight, weight);
-	} else {
-		reweight_eevdf(cfs_rq, se, weight);
 	}
 
 	update_load_set(&se->load, weight);
@@ -4821,11 +4829,14 @@ static inline unsigned long task_util(struct task_struct *p)
 	return READ_ONCE(p->se.avg.util_avg);
 }
 
-static inline unsigned long _task_util_est(struct task_struct *p)
+static inline unsigned long task_runnable(struct task_struct *p)
 {
-	struct util_est ue = READ_ONCE(p->se.avg.util_est);
+	return READ_ONCE(p->se.avg.runnable_avg);
+}
 
-	return max(ue.ewma, (ue.enqueued & ~UTIL_AVG_UNCHANGED));
+static inline unsigned long _task_util_est(struct task_struct *p)
+{
+	return READ_ONCE(p->se.avg.util_est) & ~UTIL_AVG_UNCHANGED;
 }
 
 static inline unsigned long task_util_est(struct task_struct *p)
@@ -4842,9 +4853,9 @@ static inline void util_est_enqueue(struct cfs_rq *cfs_rq,
 		return;
 
 	/* Update root cfs_rq's estimated utilization */
-	enqueued  = cfs_rq->avg.util_est.enqueued;
+	enqueued  = cfs_rq->avg.util_est;
 	enqueued += _task_util_est(p);
-	WRITE_ONCE(cfs_rq->avg.util_est.enqueued, enqueued);
+	WRITE_ONCE(cfs_rq->avg.util_est, enqueued);
 
 	trace_sched_util_est_cfs_tp(cfs_rq);
 }
@@ -4858,34 +4869,20 @@ static inline void util_est_dequeue(struct cfs_rq *cfs_rq,
 		return;
 
 	/* Update root cfs_rq's estimated utilization */
-	enqueued  = cfs_rq->avg.util_est.enqueued;
+	enqueued  = cfs_rq->avg.util_est;
 	enqueued -= min_t(unsigned int, enqueued, _task_util_est(p));
-	WRITE_ONCE(cfs_rq->avg.util_est.enqueued, enqueued);
+	WRITE_ONCE(cfs_rq->avg.util_est, enqueued);
 
 	trace_sched_util_est_cfs_tp(cfs_rq);
 }
 
 #define UTIL_EST_MARGIN (SCHED_CAPACITY_SCALE / 100)
 
-/*
- * Check if a (signed) value is within a specified (unsigned) margin,
- * based on the observation that:
- *
- *     abs(x) < y := (unsigned)(x + y - 1) < (2 * y - 1)
- *
- * NOTE: this only works when value + margin < INT_MAX.
- */
-static inline bool within_margin(int value, int margin)
-{
-	return ((unsigned int)(value + margin - 1) < (2 * margin - 1));
-}
-
 static inline void util_est_update(struct cfs_rq *cfs_rq,
 				   struct task_struct *p,
 				   bool task_sleep)
 {
-	long last_ewma_diff, last_enqueued_diff;
-	struct util_est ue;
+	unsigned int ewma, dequeued, last_ewma_diff;
 
 	if (!sched_feat(UTIL_EST))
 		return;
@@ -4897,71 +4894,73 @@ static inline void util_est_update(struct cfs_rq *cfs_rq,
 	if (!task_sleep)
 		return;
 
+	/* Get current estimate of utilization */
+	ewma = READ_ONCE(p->se.avg.util_est);
+
 	/*
 	 * If the PELT values haven't changed since enqueue time,
 	 * skip the util_est update.
 	 */
-	ue = p->se.avg.util_est;
-	if (ue.enqueued & UTIL_AVG_UNCHANGED)
+	if (ewma & UTIL_AVG_UNCHANGED)
 		return;
 
-	last_enqueued_diff = ue.enqueued;
+	/* Get utilization at dequeue */
+	dequeued = task_util(p);
 
 	/*
 	 * Reset EWMA on utilization increases, the moving average is used only
 	 * to smooth utilization decreases.
 	 */
-	ue.enqueued = task_util(p);
-	if (sched_feat(UTIL_EST_FASTUP)) {
-		if (ue.ewma < ue.enqueued) {
-			ue.ewma = ue.enqueued;
-			goto done;
-		}
+	if (ewma <= dequeued) {
+		ewma = dequeued;
+		goto done;
 	}
 
 	/*
 	 * Skip update of task's estimated utilization when its members are
 	 * already ~1% close to its last activation value.
 	 */
-	last_ewma_diff = ue.enqueued - ue.ewma;
-	last_enqueued_diff -= ue.enqueued;
-	if (within_margin(last_ewma_diff, UTIL_EST_MARGIN)) {
-		if (!within_margin(last_enqueued_diff, UTIL_EST_MARGIN))
-			goto done;
-
-		return;
-	}
+	last_ewma_diff = ewma - dequeued;
+	if (last_ewma_diff < UTIL_EST_MARGIN)
+		goto done;
 
 	/*
 	 * To avoid overestimation of actual task utilization, skip updates if
 	 * we cannot grant there is idle time in this CPU.
 	 */
-	if (task_util(p) > arch_scale_cpu_capacity(cpu_of(rq_of(cfs_rq))))
+	if (dequeued > arch_scale_cpu_capacity(cpu_of(rq_of(cfs_rq))))
 		return;
 
 	/*
+	 * To avoid underestimate of task utilization, skip updates of EWMA if
+	 * we cannot grant that thread got all CPU time it wanted.
+	 */
+	if ((dequeued + UTIL_EST_MARGIN) < task_runnable(p))
+		goto done;
+
+
+	/*
 	 * Update Task's estimated utilization
 	 *
 	 * When *p completes an activation we can consolidate another sample
-	 * of the task size. This is done by storing the current PELT value
-	 * as ue.enqueued and by using this value to update the Exponential
-	 * Weighted Moving Average (EWMA):
+	 * of the task size. This is done by using this value to update the
+	 * Exponential Weighted Moving Average (EWMA):
 	 *
 	 *  ewma(t) = w *  task_util(p) + (1-w) * ewma(t-1)
 	 *          = w *  task_util(p) +         ewma(t-1)  - w * ewma(t-1)
 	 *          = w * (task_util(p) -         ewma(t-1)) +     ewma(t-1)
-	 *          = w * (      last_ewma_diff            ) +     ewma(t-1)
-	 *          = w * (last_ewma_diff  +  ewma(t-1) / w)
+	 *          = w * (      -last_ewma_diff           ) +     ewma(t-1)
+	 *          = w * (-last_ewma_diff +  ewma(t-1) / w)
 	 *
 	 * Where 'w' is the weight of new samples, which is configured to be
 	 * 0.25, thus making w=1/4 ( >>= UTIL_EST_WEIGHT_SHIFT)
 	 */
-	ue.ewma <<= UTIL_EST_WEIGHT_SHIFT;
-	ue.ewma  += last_ewma_diff;
-	ue.ewma >>= UTIL_EST_WEIGHT_SHIFT;
+	ewma <<= UTIL_EST_WEIGHT_SHIFT;
+	ewma  -= last_ewma_diff;
+	ewma >>= UTIL_EST_WEIGHT_SHIFT;
 done:
-	ue.enqueued |= UTIL_AVG_UNCHANGED;
-	WRITE_ONCE(p->se.avg.util_est, ue);
+	ewma |= UTIL_AVG_UNCHANGED;
+	WRITE_ONCE(p->se.avg.util_est, ewma);
 
 	trace_sched_util_est_se_tp(&p->se);
 }
@@ -7695,16 +7694,16 @@ cpu_util(int cpu, struct task_struct *p, int dst_cpu, int boost)
 	if (sched_feat(UTIL_EST)) {
 		unsigned long util_est;
 
-		util_est = READ_ONCE(cfs_rq->avg.util_est.enqueued);
+		util_est = READ_ONCE(cfs_rq->avg.util_est);
 
 		/*
 		 * During wake-up @p isn't enqueued yet and doesn't contribute
-		 * to any cpu_rq(cpu)->cfs.avg.util_est.enqueued.
+		 * to any cpu_rq(cpu)->cfs.avg.util_est.
 		 * If @dst_cpu == @cpu add it to "simulate" cpu_util after @p
 		 * has been enqueued.
 		 *
 		 * During exec (@dst_cpu = -1) @p is enqueued and does
-		 * contribute to cpu_rq(cpu)->cfs.util_est.enqueued.
+		 * contribute to cpu_rq(cpu)->cfs.util_est.
 		 * Remove it to "simulate" cpu_util without @p's contribution.
 		 *
 		 * Despite the task_on_rq_queued(@p) check there is still a
@@ -7833,7 +7832,7 @@ static inline void eenv_pd_busy_time(struct energy_env *eenv,
 	for_each_cpu(cpu, pd_cpus) {
 		unsigned long util = cpu_util(cpu, p, -1, 0);
 
-		busy_time += effective_cpu_util(cpu, util, ENERGY_UTIL, NULL);
+		busy_time += effective_cpu_util(cpu, util, NULL, NULL);
 	}
 
 	eenv->pd_busy_time = min(eenv->pd_cap, busy_time);
@@ -7856,7 +7855,7 @@ eenv_pd_max_util(struct energy_env *eenv, struct cpumask *pd_cpus,
 	for_each_cpu(cpu, pd_cpus) {
 		struct task_struct *tsk = (cpu == dst_cpu) ? p : NULL;
 		unsigned long util = cpu_util(cpu, p, dst_cpu, 1);
-		unsigned long eff_util;
+		unsigned long eff_util, min, max;
 
 		/*
 		 * Performance domain frequency: utilization clamping
@@ -7865,7 +7864,23 @@ eenv_pd_max_util(struct energy_env *eenv, struct cpumask *pd_cpus,
 		 * NOTE: in case RT tasks are running, by default the
 		 * FREQUENCY_UTIL's utilization can be max OPP.
 		 */
-		eff_util = effective_cpu_util(cpu, util, FREQUENCY_UTIL, tsk);
+		eff_util = effective_cpu_util(cpu, util, &min, &max);
+
+		/* Task's uclamp can modify min and max value */
+		if (tsk && uclamp_is_used()) {
+			min = max(min, uclamp_eff_value(p, UCLAMP_MIN));
+
+			/*
+			 * If there is no active max uclamp constraint,
+			 * directly use task's one, otherwise keep max.
+			 */
+			if (uclamp_rq_is_idle(cpu_rq(cpu)))
+				max = uclamp_eff_value(p, UCLAMP_MAX);
+			else
+				max = max(max, uclamp_eff_value(p, UCLAMP_MAX));
+		}
+
+		eff_util = sugov_effective_cpu_perf(cpu, eff_util, min, max);
 		max_util = max(max_util, eff_util);
 	}
 
@@ -8267,7 +8282,6 @@ static void check_preempt_wakeup_fair(struct rq *rq, struct task_struct *p, int
 	struct task_struct *curr = rq->curr;
 	struct sched_entity *se = &curr->se, *pse = &p->se;
 	struct cfs_rq *cfs_rq = task_cfs_rq(curr);
-	int next_buddy_marked = 0;
 	int cse_is_idle, pse_is_idle;
 
 	if (unlikely(se == pse))
@@ -8284,7 +8298,6 @@ static void check_preempt_wakeup_fair(struct rq *rq, struct task_struct *p, int
 
 	if (sched_feat(NEXT_BUDDY) && !(wake_flags & WF_FORK)) {
 		set_next_buddy(pse);
-		next_buddy_marked = 1;
 	}
 
 	/*
@@ -9117,7 +9130,7 @@ static int detach_tasks(struct lb_env *env)
 		case migrate_util:
 			util = task_util_est(p);
 
-			if (util > env->imbalance)
+			if (shr_bound(util, env->sd->nr_balance_failed) > env->imbalance)
 				goto next;
 
 			env->imbalance -= util;
@@ -13096,19 +13109,6 @@ next_cpu:
 	return 0;
 }
 
-#else /* CONFIG_FAIR_GROUP_SCHED */
-
-void free_fair_sched_group(struct task_group *tg) { }
-
-int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
-{
-	return 1;
-}
-
-void online_fair_sched_group(struct task_group *tg) { }
-
-void unregister_fair_sched_group(struct task_group *tg) { }
-
 #endif /* CONFIG_FAIR_GROUP_SCHED */
 
 
diff --git a/kernel/sched/features.h b/kernel/sched/features.h
index a3ddf84de4..143f55df89 100644
--- a/kernel/sched/features.h
+++ b/kernel/sched/features.h
@@ -83,7 +83,6 @@ SCHED_FEAT(WA_BIAS, true)
  * UtilEstimation. Use estimated CPU utilization.
  */
 SCHED_FEAT(UTIL_EST, true)
-SCHED_FEAT(UTIL_EST_FASTUP, true)
 
 SCHED_FEAT(LATENCY_WARN, false)
 
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index 565f8374dd..31231925f1 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -258,6 +258,36 @@ static void do_idle(void)
 	while (!need_resched()) {
 		rmb();
 
+		/*
+		 * Interrupts shouldn't be re-enabled from that point on until
+		 * the CPU sleeping instruction is reached. Otherwise an interrupt
+		 * may fire and queue a timer that would be ignored until the CPU
+		 * wakes from the sleeping instruction. And testing need_resched()
+		 * doesn't tell about pending needed timer reprogram.
+		 *
+		 * Several cases to consider:
+		 *
+		 * - SLEEP-UNTIL-PENDING-INTERRUPT based instructions such as
+		 *   "wfi" or "mwait" are fine because they can be entered with
+		 *   interrupt disabled.
+		 *
+		 * - sti;mwait() couple is fine because the interrupts are
+		 *   re-enabled only upon the execution of mwait, leaving no gap
+		 *   in-between.
+		 *
+		 * - ROLLBACK based idle handlers with the sleeping instruction
+		 *   called with interrupts enabled are NOT fine. In this scheme
+		 *   when the interrupt detects it has interrupted an idle handler,
+		 *   it rolls back to its beginning which performs the
+		 *   need_resched() check before re-executing the sleeping
+		 *   instruction. This can leak a pending needed timer reprogram.
+		 *   If such a scheme is really mandatory due to the lack of an
+		 *   appropriate CPU sleeping instruction, then a FAST-FORWARD
+		 *   must instead be applied: when the interrupt detects it has
+		 *   interrupted an idle handler, it must resume to the end of
+		 *   this idle handler so that the generic idle loop is iterated
+		 *   again to reprogram the tick.
+		 */
 		local_irq_disable();
 
 		if (cpu_is_offline(cpu)) {
diff --git a/kernel/sched/pelt.h b/kernel/sched/pelt.h
index 3a0e0dc287..9e1083465f 100644
--- a/kernel/sched/pelt.h
+++ b/kernel/sched/pelt.h
@@ -52,13 +52,13 @@ static inline void cfs_se_util_change(struct sched_avg *avg)
 		return;
 
 	/* Avoid store if the flag has been already reset */
-	enqueued = avg->util_est.enqueued;
+	enqueued = avg->util_est;
 	if (!(enqueued & UTIL_AVG_UNCHANGED))
 		return;
 
 	/* Reset flag to report util_avg has been updated */
 	enqueued &= ~UTIL_AVG_UNCHANGED;
-	WRITE_ONCE(avg->util_est.enqueued, enqueued);
+	WRITE_ONCE(avg->util_est, enqueued);
 }
 
 static inline u64 rq_clock_pelt(struct rq *rq)
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 6aaf0a3d60..3261b067b6 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -1002,24 +1002,15 @@ static void update_curr_rt(struct rq *rq)
 {
 	struct task_struct *curr = rq->curr;
 	struct sched_rt_entity *rt_se = &curr->rt;
-	u64 delta_exec;
-	u64 now;
+	s64 delta_exec;
 
 	if (curr->sched_class != &rt_sched_class)
 		return;
 
-	now = rq_clock_task(rq);
-	delta_exec = now - curr->se.exec_start;
-	if (unlikely((s64)delta_exec <= 0))
+	delta_exec = update_curr_common(rq);
+	if (unlikely(delta_exec <= 0))
 		return;
 
-	schedstat_set(curr->stats.exec_max,
-		      max(curr->stats.exec_max, delta_exec));
-
-	trace_sched_stat_runtime(curr, delta_exec, 0);
-
-	update_current_exec_runtime(curr, now, delta_exec);
-
 	if (!rt_bandwidth_enabled())
 		return;
 
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 2e5a95486a..8c817d0a92 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -79,6 +79,8 @@
 # include <asm/paravirt_api_clock.h>
 #endif
 
+#include <asm/barrier.h>
+
 #include "cpupri.h"
 #include "cpudeadline.h"
 
@@ -273,8 +275,6 @@ struct rt_bandwidth {
 	unsigned int		rt_period_active;
 };
 
-void __dl_clear_params(struct task_struct *p);
-
 static inline int dl_bandwidth_enabled(void)
 {
 	return sysctl_sched_rt_runtime >= 0;
@@ -315,6 +315,33 @@ extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *att
 extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
 extern int  dl_bw_check_overflow(int cpu);
 
+/*
+ * SCHED_DEADLINE supports servers (nested scheduling) with the following
+ * interface:
+ *
+ *   dl_se::rq -- runqueue we belong to.
+ *
+ *   dl_se::server_has_tasks() -- used on bandwidth enforcement; we 'stop' the
+ *                                server when it runs out of tasks to run.
+ *
+ *   dl_se::server_pick() -- nested pick_next_task(); we yield the period if this
+ *                           returns NULL.
+ *
+ *   dl_server_update() -- called from update_curr_common(), propagates runtime
+ *                         to the server.
+ *
+ *   dl_server_start()
+ *   dl_server_stop()  -- start/stop the server when it has (no) tasks.
+ *
+ *   dl_server_init() -- initializes the server.
+ */
+extern void dl_server_update(struct sched_dl_entity *dl_se, s64 delta_exec);
+extern void dl_server_start(struct sched_dl_entity *dl_se);
+extern void dl_server_stop(struct sched_dl_entity *dl_se);
+extern void dl_server_init(struct sched_dl_entity *dl_se, struct rq *rq,
+		    dl_server_has_tasks_f has_tasks,
+		    dl_server_pick_f pick);
+
 #ifdef CONFIG_CGROUP_SCHED
 
 struct cfs_rq;
@@ -436,10 +463,21 @@ static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
 
 extern int tg_nop(struct task_group *tg, void *data);
 
+#ifdef CONFIG_FAIR_GROUP_SCHED
 extern void free_fair_sched_group(struct task_group *tg);
 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
 extern void online_fair_sched_group(struct task_group *tg);
 extern void unregister_fair_sched_group(struct task_group *tg);
+#else
+static inline void free_fair_sched_group(struct task_group *tg) { }
+static inline int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
+{
+       return 1;
+}
+static inline void online_fair_sched_group(struct task_group *tg) { }
+static inline void unregister_fair_sched_group(struct task_group *tg) { }
+#endif
+
 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
 			struct sched_entity *se, int cpu,
 			struct sched_entity *parent);
@@ -2179,6 +2217,10 @@ extern const u32		sched_prio_to_wmult[40];
  * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
  *        in the runqueue.
  *
+ * NOCLOCK - skip the update_rq_clock() (avoids double updates)
+ *
+ * MIGRATION - p->on_rq == TASK_ON_RQ_MIGRATING (used for DEADLINE)
+ *
  * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
  * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
  * ENQUEUE_MIGRATED  - the task was migrated during wakeup
@@ -2189,6 +2231,7 @@ extern const u32		sched_prio_to_wmult[40];
 #define DEQUEUE_SAVE		0x02 /* Matches ENQUEUE_RESTORE */
 #define DEQUEUE_MOVE		0x04 /* Matches ENQUEUE_MOVE */
 #define DEQUEUE_NOCLOCK		0x08 /* Matches ENQUEUE_NOCLOCK */
+#define DEQUEUE_MIGRATING	0x100 /* Matches ENQUEUE_MIGRATING */
 
 #define ENQUEUE_WAKEUP		0x01
 #define ENQUEUE_RESTORE		0x02
@@ -2203,6 +2246,7 @@ extern const u32		sched_prio_to_wmult[40];
 #define ENQUEUE_MIGRATED	0x00
 #endif
 #define ENQUEUE_INITIAL		0x80
+#define ENQUEUE_MIGRATING	0x100
 
 #define RETRY_TASK		((void *)-1UL)
 
@@ -2212,6 +2256,8 @@ struct affinity_context {
 	unsigned int flags;
 };
 
+extern s64 update_curr_common(struct rq *rq);
+
 struct sched_class {
 
 #ifdef CONFIG_UCLAMP_TASK
@@ -2425,8 +2471,7 @@ extern struct rt_bandwidth def_rt_bandwidth;
 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
 extern bool sched_rt_bandwidth_account(struct rt_rq *rt_rq);
 
-extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
-extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
+extern void init_dl_entity(struct sched_dl_entity *dl_se);
 
 #define BW_SHIFT		20
 #define BW_UNIT			(1 << BW_SHIFT)
@@ -2822,6 +2867,7 @@ DEFINE_LOCK_GUARD_2(double_rq_lock, struct rq,
 		    double_rq_lock(_T->lock, _T->lock2),
 		    double_rq_unlock(_T->lock, _T->lock2))
 
+extern struct sched_entity *__pick_root_entity(struct cfs_rq *cfs_rq);
 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
 
@@ -2961,24 +3007,14 @@ static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
 #endif
 
 #ifdef CONFIG_SMP
-/**
- * enum cpu_util_type - CPU utilization type
- * @FREQUENCY_UTIL:	Utilization used to select frequency
- * @ENERGY_UTIL:	Utilization used during energy calculation
- *
- * The utilization signals of all scheduling classes (CFS/RT/DL) and IRQ time
- * need to be aggregated differently depending on the usage made of them. This
- * enum is used within effective_cpu_util() to differentiate the types of
- * utilization expected by the callers, and adjust the aggregation accordingly.
- */
-enum cpu_util_type {
-	FREQUENCY_UTIL,
-	ENERGY_UTIL,
-};
-
 unsigned long effective_cpu_util(int cpu, unsigned long util_cfs,
-				 enum cpu_util_type type,
-				 struct task_struct *p);
+				 unsigned long *min,
+				 unsigned long *max);
+
+unsigned long sugov_effective_cpu_perf(int cpu, unsigned long actual,
+				 unsigned long min,
+				 unsigned long max);
+
 
 /*
  * Verify the fitness of task @p to run on @cpu taking into account the
@@ -3035,59 +3071,6 @@ static inline bool uclamp_rq_is_idle(struct rq *rq)
 	return rq->uclamp_flags & UCLAMP_FLAG_IDLE;
 }
 
-/**
- * uclamp_rq_util_with - clamp @util with @rq and @p effective uclamp values.
- * @rq:		The rq to clamp against. Must not be NULL.
- * @util:	The util value to clamp.
- * @p:		The task to clamp against. Can be NULL if you want to clamp
- *		against @rq only.
- *
- * Clamps the passed @util to the max(@rq, @p) effective uclamp values.
- *
- * If sched_uclamp_used static key is disabled, then just return the util
- * without any clamping since uclamp aggregation at the rq level in the fast
- * path is disabled, rendering this operation a NOP.
- *
- * Use uclamp_eff_value() if you don't care about uclamp values at rq level. It
- * will return the correct effective uclamp value of the task even if the
- * static key is disabled.
- */
-static __always_inline
-unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
-				  struct task_struct *p)
-{
-	unsigned long min_util = 0;
-	unsigned long max_util = 0;
-
-	if (!static_branch_likely(&sched_uclamp_used))
-		return util;
-
-	if (p) {
-		min_util = uclamp_eff_value(p, UCLAMP_MIN);
-		max_util = uclamp_eff_value(p, UCLAMP_MAX);
-
-		/*
-		 * Ignore last runnable task's max clamp, as this task will
-		 * reset it. Similarly, no need to read the rq's min clamp.
-		 */
-		if (uclamp_rq_is_idle(rq))
-			goto out;
-	}
-
-	min_util = max_t(unsigned long, min_util, uclamp_rq_get(rq, UCLAMP_MIN));
-	max_util = max_t(unsigned long, max_util, uclamp_rq_get(rq, UCLAMP_MAX));
-out:
-	/*
-	 * Since CPU's {min,max}_util clamps are MAX aggregated considering
-	 * RUNNABLE tasks with _different_ clamps, we can end up with an
-	 * inversion. Fix it now when the clamps are applied.
-	 */
-	if (unlikely(min_util >= max_util))
-		return min_util;
-
-	return clamp(util, min_util, max_util);
-}
-
 /* Is the rq being capped/throttled by uclamp_max? */
 static inline bool uclamp_rq_is_capped(struct rq *rq)
 {
@@ -3125,13 +3108,6 @@ static inline unsigned long uclamp_eff_value(struct task_struct *p,
 	return SCHED_CAPACITY_SCALE;
 }
 
-static inline
-unsigned long uclamp_rq_util_with(struct rq *rq, unsigned long util,
-				  struct task_struct *p)
-{
-	return util;
-}
-
 static inline bool uclamp_rq_is_capped(struct rq *rq) { return false; }
 
 static inline bool uclamp_is_used(void)
@@ -3261,16 +3237,6 @@ extern int sched_dynamic_mode(const char *str);
 extern void sched_dynamic_update(int mode);
 #endif
 
-static inline void update_current_exec_runtime(struct task_struct *curr,
-						u64 now, u64 delta_exec)
-{
-	curr->se.sum_exec_runtime += delta_exec;
-	account_group_exec_runtime(curr, delta_exec);
-
-	curr->se.exec_start = now;
-	cgroup_account_cputime(curr, delta_exec);
-}
-
 #ifdef CONFIG_SCHED_MM_CID
 
 #define SCHED_MM_CID_PERIOD_NS	(100ULL * 1000000)	/* 100ms */
@@ -3481,13 +3447,19 @@ static inline void switch_mm_cid(struct rq *rq,
 		 * between rq->curr store and load of {prev,next}->mm->pcpu_cid[cpu].
 		 * Provide it here.
 		 */
-		if (!prev->mm)                          // from kernel
+		if (!prev->mm) {                        // from kernel
 			smp_mb();
-		/*
-		 * user -> user transition guarantees a memory barrier through
-		 * switch_mm() when current->mm changes. If current->mm is
-		 * unchanged, no barrier is needed.
-		 */
+		} else {				// from user
+			/*
+			 * user->user transition relies on an implicit
+			 * memory barrier in switch_mm() when
+			 * current->mm changes. If the architecture
+			 * switch_mm() does not have an implicit memory
+			 * barrier, it is emitted here.  If current->mm
+			 * is unchanged, no barrier is needed.
+			 */
+			smp_mb__after_switch_mm();
+		}
 	}
 	if (prev->mm_cid_active) {
 		mm_cid_snapshot_time(rq, prev->mm);
diff --git a/kernel/sched/stop_task.c b/kernel/sched/stop_task.c
index 6cf7304e64..b1b8fe61c5 100644
--- a/kernel/sched/stop_task.c
+++ b/kernel/sched/stop_task.c
@@ -70,18 +70,7 @@ static void yield_task_stop(struct rq *rq)
 
 static void put_prev_task_stop(struct rq *rq, struct task_struct *prev)
 {
-	struct task_struct *curr = rq->curr;
-	u64 now, delta_exec;
-
-	now = rq_clock_task(rq);
-	delta_exec = now - curr->se.exec_start;
-	if (unlikely((s64)delta_exec < 0))
-		delta_exec = 0;
-
-	schedstat_set(curr->stats.exec_max,
-		      max(curr->stats.exec_max, delta_exec));
-
-	update_current_exec_runtime(curr, now, delta_exec);
+	update_curr_common(rq);
 }
 
 /*