path: root/SOURCES/cachy-bore.patch

From 2328e7500823151cb2f119b847454e63e9da0f64 Mon Sep 17 00:00:00 2001
From: Masahito S <firelzrd@gmail.com>
Date: Thu, 3 Oct 2024 17:33:57 +0900
Subject: [PATCH] linux6.11.y-bore5.6.0

---
 include/linux/sched.h      |  20 +-
 include/linux/sched/bore.h |  37 ++++
 init/Kconfig               |  17 ++
 kernel/Kconfig.hz          |  17 ++
 kernel/fork.c              |   5 +
 kernel/sched/Makefile      |   1 +
 kernel/sched/bore.c        | 380 +++++++++++++++++++++++++++++++++++++
 kernel/sched/core.c        |   7 +
 kernel/sched/debug.c       |  60 +++++-
 kernel/sched/fair.c        |  89 ++++++++-
 kernel/sched/features.h    |   4 +
 kernel/sched/sched.h       |   7 +
 12 files changed, 639 insertions(+), 5 deletions(-)
 create mode 100644 include/linux/sched/bore.h
 create mode 100644 kernel/sched/bore.c

diff --git a/include/linux/sched.h b/include/linux/sched.h
index f8d150343d..2481cf0125 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -535,6 +535,14 @@ struct sched_statistics {
 #endif /* CONFIG_SCHEDSTATS */
 } ____cacheline_aligned;
 
+#ifdef CONFIG_SCHED_BORE
+struct sched_burst_cache {
+	u8				score;
+	u32				count;
+	u64				timestamp;
+};
+#endif // CONFIG_SCHED_BORE
+
 struct sched_entity {
 	/* For load-balancing: */
 	struct load_weight		load;
@@ -543,12 +551,22 @@ struct sched_entity {
 	u64				min_vruntime;
 
 	struct list_head		group_node;
-	unsigned int			on_rq;
+	unsigned char			on_rq;
+	unsigned char			rel_deadline;
 
 	u64				exec_start;
 	u64				sum_exec_runtime;
 	u64				prev_sum_exec_runtime;
 	u64				vruntime;
+#ifdef CONFIG_SCHED_BORE
+	u64				burst_time;
+	u8				prev_burst_penalty;
+	u8				curr_burst_penalty;
+	u8				burst_penalty;
+	u8				burst_score;
+	struct sched_burst_cache child_burst;
+	struct sched_burst_cache group_burst;
+#endif // CONFIG_SCHED_BORE
 	s64				vlag;
 	u64				slice;
 
diff --git a/include/linux/sched/bore.h b/include/linux/sched/bore.h
new file mode 100644
index 0000000000..12a613a94f
--- /dev/null
+++ b/include/linux/sched/bore.h
@@ -0,0 +1,37 @@
+
+#include <linux/sched.h>
+#include <linux/sched/cputime.h>
+
+#ifndef _LINUX_SCHED_BORE_H
+#define _LINUX_SCHED_BORE_H
+
+#ifdef CONFIG_SCHED_BORE
+extern u8   __read_mostly sched_bore;
+extern u8   __read_mostly sched_burst_exclude_kthreads;
+extern u8   __read_mostly sched_burst_smoothness_long;
+extern u8   __read_mostly sched_burst_smoothness_short;
+extern u8   __read_mostly sched_burst_fork_atavistic;
+extern u8   __read_mostly sched_burst_parity_threshold;
+extern u8   __read_mostly sched_burst_penalty_offset;
+extern uint __read_mostly sched_burst_penalty_scale;
+extern uint __read_mostly sched_burst_cache_lifetime;
+extern uint __read_mostly sched_deadline_boost_mask;
+
+extern void update_burst_score(struct sched_entity *se);
+extern void update_burst_penalty(struct sched_entity *se);
+
+extern void restart_burst(struct sched_entity *se);
+extern void restart_burst_rescale_deadline(struct sched_entity *se);
+
+extern int sched_bore_update_handler(const struct ctl_table *table, int write,
+		void __user *buffer, size_t *lenp, loff_t *ppos);
+
+extern void sched_clone_bore(
+	struct task_struct *p, struct task_struct *parent, u64 clone_flags);
+
+extern void init_task_bore(struct task_struct *p);
+
+extern void reweight_entity(
+	struct cfs_rq *cfs_rq, struct sched_entity *se, unsigned long weight);
+#endif // CONFIG_SCHED_BORE
+#endif // _LINUX_SCHED_BORE_H
diff --git a/init/Kconfig b/init/Kconfig
index 5783a0b875..b648ed538c 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -1297,6 +1297,23 @@ config CHECKPOINT_RESTORE
 
 	  If unsure, say N here.
 
+config SCHED_BORE
+	bool "Burst-Oriented Response Enhancer"
+	default y
+	help
+	  In Desktop and Mobile computing, one might prefer interactive
+	  tasks to keep responsive no matter what they run in the background.
+
+	  Enabling this kernel feature modifies the scheduler to discriminate
+	  tasks by their burst time (runtime since it last went sleeping or
+	  yielding state) and prioritize those that run less bursty.
+	  Such tasks usually include window compositor, widgets backend,
+	  terminal emulator, video playback, games and so on.
+	  With a little impact to scheduling fairness, it may improve
+	  responsiveness especially under heavy background workload.
+
+	  If unsure, say Y here.
+
 config SCHED_AUTOGROUP
 	bool "Automatic process group scheduling"
 	select CGROUPS
diff --git a/kernel/Kconfig.hz b/kernel/Kconfig.hz
index 38ef6d0688..253c566b59 100644
--- a/kernel/Kconfig.hz
+++ b/kernel/Kconfig.hz
@@ -55,5 +55,22 @@ config HZ
 	default 300 if HZ_300
 	default 1000 if HZ_1000
 
+config MIN_BASE_SLICE_NS
+	int "Default value for min_base_slice_ns"
+	default 2000000
+	help
+	 The BORE Scheduler automatically calculates the optimal base
+	 slice for the configured HZ using the following equation:
+	 
+	 base_slice_ns =
+	 	1000000000/HZ * DIV_ROUNDUP(min_base_slice_ns, 1000000000/HZ)
+	 
+	 This option sets the default lower bound limit of the base slice
+	 to prevent the loss of task throughput due to overscheduling.
+	 
+	 Setting this value too high can cause the system to boot with
+	 an unnecessarily large base slice, resulting in high scheduling
+	 latency and poor system responsiveness.
+
 config SCHED_HRTICK
 	def_bool HIGH_RES_TIMERS
diff --git a/kernel/fork.c b/kernel/fork.c
index cc760491f2..179b884da3 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -111,6 +111,8 @@
 #include <asm/cacheflush.h>
 #include <asm/tlbflush.h>
 
+#include <linux/sched/bore.h>
+
 #include <trace/events/sched.h>
 
 #define CREATE_TRACE_POINTS
@@ -2344,6 +2346,9 @@ __latent_entropy struct task_struct *copy_process(
 	retval = sched_fork(clone_flags, p);
 	if (retval)
 		goto bad_fork_cleanup_policy;
+#ifdef CONFIG_SCHED_BORE
+	sched_clone_bore(p, current, clone_flags);
+#endif // CONFIG_SCHED_BORE
 
 	retval = perf_event_init_task(p, clone_flags);
 	if (retval)
diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile
index 976092b7bd..293aad6754 100644
--- a/kernel/sched/Makefile
+++ b/kernel/sched/Makefile
@@ -32,3 +32,4 @@ obj-y += core.o
 obj-y += fair.o
 obj-y += build_policy.o
 obj-y += build_utility.o
+obj-y += bore.o
diff --git a/kernel/sched/bore.c b/kernel/sched/bore.c
new file mode 100644
index 0000000000..62a0191a32
--- /dev/null
+++ b/kernel/sched/bore.c
@@ -0,0 +1,380 @@
+/*
+ *  Burst-Oriented Response Enhancer (BORE) CPU Scheduler
+ *  Copyright (C) 2021-2024 Masahito Suzuki <firelzrd@gmail.com>
+ */
+#include <linux/cpuset.h>
+#include <linux/sched/bore.h>
+#include "sched.h"
+
+#ifdef CONFIG_SCHED_BORE
+u8   __read_mostly sched_bore                   = 1;
+u8   __read_mostly sched_burst_exclude_kthreads = 1;
+u8   __read_mostly sched_burst_smoothness_long  = 1;
+u8   __read_mostly sched_burst_smoothness_short = 0;
+u8   __read_mostly sched_burst_fork_atavistic   = 2;
+u8   __read_mostly sched_burst_parity_threshold = 2;
+u8   __read_mostly sched_burst_penalty_offset   = 24;
+uint __read_mostly sched_burst_penalty_scale    = 1280;
+uint __read_mostly sched_burst_cache_lifetime   = 60000000;
+uint __read_mostly sched_deadline_boost_mask    = ENQUEUE_INITIAL
+                                                | ENQUEUE_WAKEUP;
+static int __maybe_unused sixty_four     = 64;
+static int __maybe_unused maxval_u8      = 255;
+static int __maybe_unused maxval_12_bits = 4095;
+
+#define MAX_BURST_PENALTY (39U <<2)
+
+static inline u32 log2plus1_u64_u32f8(u64 v) {
+	u32 integral = fls64(v);
+	u8  fractional = v << (64 - integral) >> 55;
+	return integral << 8 | fractional;
+}
+
+static inline u32 calc_burst_penalty(u64 burst_time) {
+	u32 greed, tolerance, penalty, scaled_penalty;
+	
+	greed = log2plus1_u64_u32f8(burst_time);
+	tolerance = sched_burst_penalty_offset << 8;
+	penalty = max(0, (s32)(greed - tolerance));
+	scaled_penalty = penalty * sched_burst_penalty_scale >> 16;
+
+	return min(MAX_BURST_PENALTY, scaled_penalty);
+}
+
+static inline u64 __scale_slice(u64 delta, u8 score)
+{return mul_u64_u32_shr(delta, sched_prio_to_wmult[score], 22);}
+
+static inline u64 __unscale_slice(u64 delta, u8 score)
+{return mul_u64_u32_shr(delta, sched_prio_to_weight[score], 10);}
+
+static void reweight_task_by_prio(struct task_struct *p, int prio) {
+	struct sched_entity *se = &p->se;
+	unsigned long weight = scale_load(sched_prio_to_weight[prio]);
+
+	reweight_entity(cfs_rq_of(se), se, weight);
+	se->load.inv_weight = sched_prio_to_wmult[prio];
+}
+
+static inline u8 effective_prio(struct task_struct *p) {
+	u8 prio = p->static_prio - MAX_RT_PRIO;
+	if (likely(sched_bore))
+		prio += p->se.burst_score;
+	return min(39, prio);
+}
+
+void update_burst_score(struct sched_entity *se) {
+	if (!entity_is_task(se)) return;
+	struct task_struct *p = task_of(se);
+	u8 prev_prio = effective_prio(p);
+
+	u8 burst_score = 0;
+	if (!((p->flags & PF_KTHREAD) && likely(sched_burst_exclude_kthreads)))
+		burst_score = se->burst_penalty >> 2;
+	se->burst_score = burst_score;
+
+	u8 new_prio = effective_prio(p);
+	if (new_prio != prev_prio)
+		reweight_task_by_prio(p, new_prio);
+}
+
+void update_burst_penalty(struct sched_entity *se) {
+	se->curr_burst_penalty = calc_burst_penalty(se->burst_time);
+	se->burst_penalty = max(se->prev_burst_penalty, se->curr_burst_penalty);
+	update_burst_score(se);
+}
+
+static inline u32 binary_smooth(u32 new, u32 old) {
+	int increment = new - old;
+	return (0 <= increment)?
+		old + ( increment >> (int)sched_burst_smoothness_long):
+		old - (-increment >> (int)sched_burst_smoothness_short);
+}
+
+static void revolve_burst_penalty(struct sched_entity *se) {
+	se->prev_burst_penalty =
+		binary_smooth(se->curr_burst_penalty, se->prev_burst_penalty);
+	se->burst_time = 0;
+	se->curr_burst_penalty = 0;
+}
+
+inline void restart_burst(struct sched_entity *se) {
+	revolve_burst_penalty(se);
+	se->burst_penalty = se->prev_burst_penalty;
+	update_burst_score(se);
+}
+
+void restart_burst_rescale_deadline(struct sched_entity *se) {
+	s64 vscaled, wremain, vremain = se->deadline - se->vruntime;
+	struct task_struct *p = task_of(se);
+	u8 prev_prio = effective_prio(p);
+	restart_burst(se);
+	u8 new_prio = effective_prio(p);
+	if (prev_prio > new_prio) {
+		wremain = __unscale_slice(abs(vremain), prev_prio);
+		vscaled = __scale_slice(wremain, new_prio);
+		if (unlikely(vremain < 0))
+			vscaled = -vscaled;
+		se->deadline = se->vruntime + vscaled;
+	}
+}
+
+static void reset_task_weights_bore(void) {
+	struct task_struct *task;
+	struct rq *rq;
+	struct rq_flags rf;
+
+	write_lock_irq(&tasklist_lock);
+	for_each_process(task) {
+		rq = task_rq(task);
+		rq_lock_irqsave(rq, &rf);
+		reweight_task_by_prio(task, effective_prio(task));
+		rq_unlock_irqrestore(rq, &rf);
+	}
+	write_unlock_irq(&tasklist_lock);
+}
+
+int sched_bore_update_handler(const struct ctl_table *table, int write,
+		void __user *buffer, size_t *lenp, loff_t *ppos) {
+	int ret = proc_dou8vec_minmax(table, write, buffer, lenp, ppos);
+	if (ret || !write)
+		return ret;
+
+	reset_task_weights_bore();
+
+	return 0;
+}
+
+static u32 count_child_tasks(struct task_struct *p) {
+	struct task_struct *child;
+	u32 cnt = 0;
+	list_for_each_entry(child, &p->children, sibling) {cnt++;}
+	return cnt;
+}
+
+static inline bool task_is_bore_eligible(struct task_struct *p)
+{return p->sched_class == &fair_sched_class;}
+
+static inline bool burst_cache_expired(struct sched_burst_cache *bc, u64 now)
+{return (s64)(bc->timestamp + sched_burst_cache_lifetime - now) < 0;}
+
+static void update_burst_cache(struct sched_burst_cache *bc,
+		struct task_struct *p, u32 cnt, u32 sum, u64 now) {
+	u8 avg = cnt ? sum / cnt : 0;
+	bc->score = max(avg, p->se.burst_penalty);
+	bc->count = cnt;
+	bc->timestamp = now;
+}
+
+static inline void update_child_burst_direct(struct task_struct *p, u64 now) {
+	u32 cnt = 0, sum = 0;
+	struct task_struct *child;
+
+	list_for_each_entry(child, &p->children, sibling) {
+		if (!task_is_bore_eligible(child)) continue;
+		cnt++;
+		sum += child->se.burst_penalty;
+	}
+
+	update_burst_cache(&p->se.child_burst, p, cnt, sum, now);
+}
+
+static inline u8 inherit_burst_direct(struct task_struct *p, u64 now) {
+	struct task_struct *parent = p;
+	if (burst_cache_expired(&parent->se.child_burst, now))
+		update_child_burst_direct(parent, now);
+
+	return parent->se.child_burst.score;
+}
+
+static void update_child_burst_topological(
+	struct task_struct *p, u64 now, u32 depth, u32 *acnt, u32 *asum) {
+	u32 cnt = 0, dcnt = 0, sum = 0;
+	struct task_struct *child, *dec;
+
+	list_for_each_entry(child, &p->children, sibling) {
+		dec = child;
+		while ((dcnt = count_child_tasks(dec)) == 1)
+			dec = list_first_entry(&dec->children, struct task_struct, sibling);
+		
+		if (!dcnt || !depth) {
+			if (!task_is_bore_eligible(dec)) continue;
+			cnt++;
+			sum += dec->se.burst_penalty;
+			continue;
+		}
+		if (!burst_cache_expired(&dec->se.child_burst, now)) {
+			cnt += dec->se.child_burst.count;
+			sum += (u32)dec->se.child_burst.score * dec->se.child_burst.count;
+			continue;
+		}
+		update_child_burst_topological(dec, now, depth - 1, &cnt, &sum);
+	}
+
+	update_burst_cache(&p->se.child_burst, p, cnt, sum, now);
+	*acnt += cnt;
+	*asum += sum;
+}
+
+static inline u8 inherit_burst_topological(struct task_struct *p, u64 now) {
+	struct task_struct *anc = p;
+	u32 cnt = 0, sum = 0;
+
+	while (anc->real_parent != anc && count_child_tasks(anc) == 1)
+		anc = anc->real_parent;
+
+	if (burst_cache_expired(&anc->se.child_burst, now))
+		update_child_burst_topological(
+			anc, now, sched_burst_fork_atavistic - 1, &cnt, &sum);
+
+	return anc->se.child_burst.score;
+}
+
+static inline void update_tg_burst(struct task_struct *p, u64 now) {
+	struct task_struct *task;
+	u32 cnt = 0, sum = 0;
+
+	for_each_thread(p, task) {
+		if (!task_is_bore_eligible(task)) continue;
+		cnt++;
+		sum += task->se.burst_penalty;
+	}
+
+	update_burst_cache(&p->se.group_burst, p, cnt, sum, now);
+}
+
+static inline u8 inherit_burst_tg(struct task_struct *p, u64 now) {
+	struct task_struct *parent = p->group_leader;
+	if (burst_cache_expired(&parent->se.group_burst, now))
+		update_tg_burst(parent, now);
+
+	return parent->se.group_burst.score;
+}
+
+void sched_clone_bore(
+	struct task_struct *p, struct task_struct *parent, u64 clone_flags) {
+	if (!task_is_bore_eligible(p)) return;
+
+	u64 now = ktime_get_ns();
+	read_lock(&tasklist_lock);
+	u8 penalty = (clone_flags & CLONE_THREAD) ?
+		inherit_burst_tg(parent, now) :
+		likely(sched_burst_fork_atavistic) ?
+			inherit_burst_topological(parent, now):
+			inherit_burst_direct(parent, now);
+	read_unlock(&tasklist_lock);
+
+	struct sched_entity *se = &p->se;
+	revolve_burst_penalty(se);
+	se->burst_penalty = se->prev_burst_penalty =
+		max(se->prev_burst_penalty, penalty);
+	se->child_burst.timestamp = 0;
+	se->group_burst.timestamp = 0;
+}
+
+void init_task_bore(struct task_struct *p) {
+	p->se.burst_time = 0;
+	p->se.prev_burst_penalty = 0;
+	p->se.curr_burst_penalty = 0;
+	p->se.burst_penalty = 0;
+	p->se.burst_score = 0;
+	memset(&p->se.child_burst, 0, sizeof(struct sched_burst_cache));
+	memset(&p->se.group_burst, 0, sizeof(struct sched_burst_cache));
+}
+
+#ifdef CONFIG_SYSCTL
+static struct ctl_table sched_bore_sysctls[] = {
+	{
+		.procname	= "sched_bore",
+		.data		= &sched_bore,
+		.maxlen		= sizeof(u8),
+		.mode		= 0644,
+		.proc_handler = sched_bore_update_handler,
+		.extra1		= SYSCTL_ZERO,
+		.extra2		= SYSCTL_ONE,
+	},
+	{
+		.procname	= "sched_burst_exclude_kthreads",
+		.data		= &sched_burst_exclude_kthreads,
+		.maxlen		= sizeof(u8),
+		.mode		= 0644,
+		.proc_handler = proc_dou8vec_minmax,
+		.extra1		= SYSCTL_ZERO,
+		.extra2		= SYSCTL_ONE,
+	},
+	{
+		.procname	= "sched_burst_smoothness_long",
+		.data		= &sched_burst_smoothness_long,
+		.maxlen		= sizeof(u8),
+		.mode		= 0644,
+		.proc_handler = proc_dou8vec_minmax,
+		.extra1		= SYSCTL_ZERO,
+		.extra2		= SYSCTL_ONE,
+	},
+	{
+		.procname	= "sched_burst_smoothness_short",
+		.data		= &sched_burst_smoothness_short,
+		.maxlen		= sizeof(u8),
+		.mode		= 0644,
+		.proc_handler = proc_dou8vec_minmax,
+		.extra1		= SYSCTL_ZERO,
+		.extra2		= SYSCTL_ONE,
+	},
+	{
+		.procname	= "sched_burst_fork_atavistic",
+		.data		= &sched_burst_fork_atavistic,
+		.maxlen		= sizeof(u8),
+		.mode		= 0644,
+		.proc_handler = proc_dou8vec_minmax,
+		.extra1		= SYSCTL_ZERO,
+		.extra2		= SYSCTL_THREE,
+	},
+	{
+		.procname	= "sched_burst_parity_threshold",
+		.data		= &sched_burst_parity_threshold,
+		.maxlen		= sizeof(u8),
+		.mode		= 0644,
+		.proc_handler = proc_dou8vec_minmax,
+		.extra1		= SYSCTL_ZERO,
+		.extra2		= &maxval_u8,
+	},
+	{
+		.procname	= "sched_burst_penalty_offset",
+		.data		= &sched_burst_penalty_offset,
+		.maxlen		= sizeof(u8),
+		.mode		= 0644,
+		.proc_handler = proc_dou8vec_minmax,
+		.extra1		= SYSCTL_ZERO,
+		.extra2		= &sixty_four,
+	},
+	{
+		.procname	= "sched_burst_penalty_scale",
+		.data		= &sched_burst_penalty_scale,
+		.maxlen		= sizeof(uint),
+		.mode		= 0644,
+		.proc_handler = proc_douintvec_minmax,
+		.extra1		= SYSCTL_ZERO,
+		.extra2		= &maxval_12_bits,
+	},
+	{
+		.procname	= "sched_burst_cache_lifetime",
+		.data		= &sched_burst_cache_lifetime,
+		.maxlen		= sizeof(uint),
+		.mode		= 0644,
+		.proc_handler = proc_douintvec,
+	},
+	{
+		.procname	= "sched_deadline_boost_mask",
+		.data		= &sched_deadline_boost_mask,
+		.maxlen		= sizeof(uint),
+		.mode		= 0644,
+		.proc_handler = proc_douintvec,
+	},
+};
+
+static int __init sched_bore_sysctl_init(void) {
+	register_sysctl_init("kernel", sched_bore_sysctls);
+	return 0;
+}
+late_initcall(sched_bore_sysctl_init);
+#endif // CONFIG_SYSCTL
+#endif // CONFIG_SCHED_BORE
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index f3951e4a55..9264e542c9 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -97,6 +97,8 @@
 #include "../../io_uring/io-wq.h"
 #include "../smpboot.h"
 
+#include <linux/sched/bore.h>
+
 EXPORT_TRACEPOINT_SYMBOL_GPL(ipi_send_cpu);
 EXPORT_TRACEPOINT_SYMBOL_GPL(ipi_send_cpumask);
 
@@ -8197,6 +8199,11 @@ void __init sched_init(void)
 	BUG_ON(&dl_sched_class != &stop_sched_class + 1);
 #endif
 
+#ifdef CONFIG_SCHED_BORE
+	printk(KERN_INFO "BORE (Burst-Oriented Response Enhancer) CPU Scheduler modification 5.6.0 by Masahito Suzuki");
+	init_task_bore(&init_task);
+#endif // CONFIG_SCHED_BORE
+
 	wait_bit_init();
 
 #ifdef CONFIG_FAIR_GROUP_SCHED
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index c1eb9a1afd..e2da8d7738 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -167,7 +167,52 @@ static const struct file_operations sched_feat_fops = {
 };
 
 #ifdef CONFIG_SMP
+#ifdef CONFIG_SCHED_BORE
+static ssize_t sched_min_base_slice_write(struct file *filp, const char __user *ubuf,
+				   size_t cnt, loff_t *ppos)
+{
+	char buf[16];
+	unsigned int value;
+
+	if (cnt > 15)
+		cnt = 15;
+
+	if (copy_from_user(&buf, ubuf, cnt))
+		return -EFAULT;
+	buf[cnt] = '\0';
+
+	if (kstrtouint(buf, 10, &value))
+		return -EINVAL;
 
+	if (!value)
+		return -EINVAL;
+
+	sysctl_sched_min_base_slice = value;
+	sched_update_min_base_slice();
+
+	*ppos += cnt;
+	return cnt;
+}
+
+static int sched_min_base_slice_show(struct seq_file *m, void *v)
+{
+	seq_printf(m, "%d\n", sysctl_sched_min_base_slice);
+	return 0;
+}
+
+static int sched_min_base_slice_open(struct inode *inode, struct file *filp)
+{
+	return single_open(filp, sched_min_base_slice_show, NULL);
+}
+
+static const struct file_operations sched_min_base_slice_fops = {
+	.open		= sched_min_base_slice_open,
+	.write		= sched_min_base_slice_write,
+	.read		= seq_read,
+	.llseek		= seq_lseek,
+	.release	= single_release,
+};
+#else // !CONFIG_SCHED_BORE
 static ssize_t sched_scaling_write(struct file *filp, const char __user *ubuf,
 				   size_t cnt, loff_t *ppos)
 {
@@ -213,7 +258,7 @@ static const struct file_operations sched_scaling_fops = {
 	.llseek		= seq_lseek,
 	.release	= single_release,
 };
-
+#endif // CONFIG_SCHED_BORE
 #endif /* SMP */
 
 #ifdef CONFIG_PREEMPT_DYNAMIC
@@ -347,13 +392,20 @@ static __init int sched_init_debug(void)
 	debugfs_create_file("preempt", 0644, debugfs_sched, NULL, &sched_dynamic_fops);
 #endif
 
+#ifdef CONFIG_SCHED_BORE
+	debugfs_create_file("min_base_slice_ns", 0644, debugfs_sched, NULL, &sched_min_base_slice_fops);
+	debugfs_create_u32("base_slice_ns", 0400, debugfs_sched, &sysctl_sched_base_slice);
+#else // !CONFIG_SCHED_BORE
 	debugfs_create_u32("base_slice_ns", 0644, debugfs_sched, &sysctl_sched_base_slice);
+#endif // CONFIG_SCHED_BORE
 
 	debugfs_create_u32("latency_warn_ms", 0644, debugfs_sched, &sysctl_resched_latency_warn_ms);
 	debugfs_create_u32("latency_warn_once", 0644, debugfs_sched, &sysctl_resched_latency_warn_once);
 
 #ifdef CONFIG_SMP
+#if !defined(CONFIG_SCHED_BORE)
 	debugfs_create_file("tunable_scaling", 0644, debugfs_sched, NULL, &sched_scaling_fops);
+#endif // CONFIG_SCHED_BORE
 	debugfs_create_u32("migration_cost_ns", 0644, debugfs_sched, &sysctl_sched_migration_cost);
 	debugfs_create_u32("nr_migrate", 0644, debugfs_sched, &sysctl_sched_nr_migrate);
 
@@ -596,6 +648,9 @@ print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
 		SPLIT_NS(schedstat_val_or_zero(p->stats.sum_sleep_runtime)),
 		SPLIT_NS(schedstat_val_or_zero(p->stats.sum_block_runtime)));
 
+#ifdef CONFIG_SCHED_BORE
+	SEQ_printf(m, " %2d", p->se.burst_score);
+#endif // CONFIG_SCHED_BORE
 #ifdef CONFIG_NUMA_BALANCING
 	SEQ_printf(m, " %d %d", task_node(p), task_numa_group_id(p));
 #endif
@@ -1069,6 +1124,9 @@ void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns,
 
 	P(se.load.weight);
 #ifdef CONFIG_SMP
+#ifdef CONFIG_SCHED_BORE
+	P(se.burst_score);
+#endif // CONFIG_SCHED_BORE
 	P(se.avg.load_sum);
 	P(se.avg.runnable_sum);
 	P(se.avg.util_sum);
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 9057584ec0..465d2626ee 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -55,6 +55,8 @@
 #include "stats.h"
 #include "autogroup.h"
 
+#include <linux/sched/bore.h>
+
 /*
  * The initial- and re-scaling of tunables is configurable
  *
@@ -64,17 +66,29 @@
  *   SCHED_TUNABLESCALING_LOG - scaled logarithmically, *1+ilog(ncpus)
  *   SCHED_TUNABLESCALING_LINEAR - scaled linear, *ncpus
  *
- * (default SCHED_TUNABLESCALING_LOG = *(1+ilog(ncpus))
+ * (BORE  default SCHED_TUNABLESCALING_NONE = *1 constant)
+ * (EEVDF default SCHED_TUNABLESCALING_LOG  = *(1+ilog(ncpus))
  */
+#ifdef CONFIG_SCHED_BORE
+unsigned int sysctl_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
+#else // !CONFIG_SCHED_BORE
 unsigned int sysctl_sched_tunable_scaling = SCHED_TUNABLESCALING_LOG;
+#endif // CONFIG_SCHED_BORE
 
 /*
  * Minimal preemption granularity for CPU-bound tasks:
  *
- * (default: 0.75 msec * (1 + ilog(ncpus)), units: nanoseconds)
+ * (BORE  default: max(1 sec / HZ, min_base_slice) constant, units: nanoseconds)
+ * (EEVDF default: 0.75 msec * (1 + ilog(ncpus)), units: nanoseconds)
  */
+#ifdef CONFIG_SCHED_BORE
+unsigned int            sysctl_sched_base_slice = 1000000000ULL / HZ;
+static unsigned int configured_sched_base_slice = 1000000000ULL / HZ;
+unsigned int        sysctl_sched_min_base_slice = CONFIG_MIN_BASE_SLICE_NS;
+#else // !CONFIG_SCHED_BORE
 unsigned int sysctl_sched_base_slice			= 750000ULL;
 static unsigned int normalized_sysctl_sched_base_slice	= 750000ULL;
+#endif // CONFIG_SCHED_BORE
 
 const_debug unsigned int sysctl_sched_migration_cost	= 500000UL;
 
@@ -188,6 +202,18 @@ static inline void update_load_set(struct load_weight *lw, unsigned long w)
  *
  * This idea comes from the SD scheduler of Con Kolivas:
  */
+#ifdef CONFIG_SCHED_BORE
+static void update_sysctl(void) {
+	unsigned int base_slice = configured_sched_base_slice;
+	unsigned int min_base_slice = sysctl_sched_min_base_slice;
+
+	if (min_base_slice)
+		base_slice *= DIV_ROUND_UP(min_base_slice, base_slice);
+
+	sysctl_sched_base_slice = base_slice;
+}
+void sched_update_min_base_slice(void) { update_sysctl(); }
+#else // !CONFIG_SCHED_BORE
 static unsigned int get_update_sysctl_factor(void)
 {
 	unsigned int cpus = min_t(unsigned int, num_online_cpus(), 8);
@@ -218,6 +244,7 @@ static void update_sysctl(void)
 	SET_SYSCTL(sched_base_slice);
 #undef SET_SYSCTL
 }
+#endif // CONFIG_SCHED_BORE
 
 void __init sched_init_granularity(void)
 {
@@ -695,6 +722,9 @@ static s64 entity_lag(u64 avruntime, struct sched_entity *se)
 
 	vlag = avruntime - se->vruntime;
 	limit = calc_delta_fair(max_t(u64, 2*se->slice, TICK_NSEC), se);
+#ifdef CONFIG_SCHED_BORE
+	limit >>= !!sched_bore;
+#endif // CONFIG_SCHED_BORE
 
 	return clamp(vlag, -limit, limit);
 }
@@ -896,6 +926,10 @@ static struct sched_entity *pick_eevdf(struct cfs_rq *cfs_rq)
 	 * until it gets a new slice. See the HACK in set_next_entity().
 	 */
 	if (sched_feat(RUN_TO_PARITY) && curr && curr->vlag == curr->deadline)
+#ifdef CONFIG_SCHED_BORE
+		if (!(likely(sched_bore) && likely(sched_burst_parity_threshold) &&
+			sched_burst_parity_threshold < cfs_rq->nr_running))
+#endif // CONFIG_SCHED_BORE
 		return curr;
 
 	/* Pick the leftmost entity if it's eligible */
@@ -954,6 +988,7 @@ struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq)
  * Scheduling class statistics methods:
  */
 #ifdef CONFIG_SMP
+#if !defined(CONFIG_SCHED_BORE)
 int sched_update_scaling(void)
 {
 	unsigned int factor = get_update_sysctl_factor();
@@ -965,6 +1000,7 @@ int sched_update_scaling(void)
 
 	return 0;
 }
+#endif // CONFIG_SCHED_BORE
 #endif
 #endif
 
@@ -1165,6 +1201,10 @@ static void update_curr(struct cfs_rq *cfs_rq)
 	if (unlikely(delta_exec <= 0))
 		return;
 
+#ifdef CONFIG_SCHED_BORE
+	curr->burst_time += delta_exec;
+	update_burst_penalty(curr);
+#endif // CONFIG_SCHED_BORE
 	curr->vruntime += calc_delta_fair(delta_exec, curr);
 	update_deadline(cfs_rq, curr);
 	update_min_vruntime(cfs_rq);
@@ -3782,7 +3822,7 @@ static void reweight_eevdf(struct sched_entity *se, u64 avruntime,
 	se->deadline = avruntime + vslice;
 }
 
-static void reweight_entity(struct cfs_rq *cfs_rq, struct sched_entity *se,
+void reweight_entity(struct cfs_rq *cfs_rq, struct sched_entity *se,
 			    unsigned long weight)
 {
 	bool curr = cfs_rq->curr == se;
@@ -5189,6 +5229,9 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
 	 *
 	 * EEVDF: placement strategy #1 / #2
 	 */
+#ifdef CONFIG_SCHED_BORE
+	if (se->vlag)
+#endif // CONFIG_SCHED_BORE
 	if (sched_feat(PLACE_LAG) && cfs_rq->nr_running) {
 		struct sched_entity *curr = cfs_rq->curr;
 		unsigned long load;
@@ -5259,6 +5302,16 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
 
 	se->vruntime = vruntime - lag;
 
+	if (sched_feat(PLACE_REL_DEADLINE) && se->rel_deadline) {
+		se->deadline += se->vruntime;
+		se->rel_deadline = 0;
+		return;
+	}
+#ifdef CONFIG_SCHED_BORE
+	else if (likely(sched_bore))
+		vslice >>= !!(flags & sched_deadline_boost_mask);
+	else
+#endif // CONFIG_SCHED_BORE
 	/*
 	 * When joining the competition; the existing tasks will be,
 	 * on average, halfway through their slice, as such start tasks
@@ -5368,6 +5421,7 @@ static __always_inline void return_cfs_rq_runtime(struct cfs_rq *cfs_rq);
 static void
 dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
 {
+	bool sleep = flags & DEQUEUE_SLEEP;
 	int action = UPDATE_TG;
 
 	if (entity_is_task(se) && task_on_rq_migrating(task_of(se)))
@@ -5395,6 +5449,11 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
 	clear_buddies(cfs_rq, se);
 
 	update_entity_lag(cfs_rq, se);
+	if (sched_feat(PLACE_REL_DEADLINE) && !sleep) {
+		se->deadline -= se->vruntime;
+		se->rel_deadline = 1;
+	}
+
 	if (se != cfs_rq->curr)
 		__dequeue_entity(cfs_rq, se);
 	se->on_rq = 0;
@@ -6846,6 +6905,14 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags)
 	bool was_sched_idle = sched_idle_rq(rq);
 
 	util_est_dequeue(&rq->cfs, p);
+#ifdef CONFIG_SCHED_BORE
+	if (task_sleep) {
+		cfs_rq = cfs_rq_of(se);
+		if (cfs_rq->curr == se)
+			update_curr(cfs_rq);
+		restart_burst(se);
+	}
+#endif // CONFIG_SCHED_BORE
 
 	for_each_sched_entity(se) {
 		cfs_rq = cfs_rq_of(se);
@@ -8632,16 +8699,25 @@ static void yield_task_fair(struct rq *rq)
 	/*
 	 * Are we the only task in the tree?
 	 */
+#if !defined(CONFIG_SCHED_BORE)
 	if (unlikely(rq->nr_running == 1))
 		return;
 
 	clear_buddies(cfs_rq, se);
+#endif // CONFIG_SCHED_BORE
 
 	update_rq_clock(rq);
 	/*
 	 * Update run-time statistics of the 'current'.
 	 */
 	update_curr(cfs_rq);
+#ifdef CONFIG_SCHED_BORE
+	restart_burst_rescale_deadline(se);
+	if (unlikely(rq->nr_running == 1))
+		return;
+
+	clear_buddies(cfs_rq, se);
+#endif // CONFIG_SCHED_BORE
 	/*
 	 * Tell update_rq_clock() that we've just updated,
 	 * so we don't do microscopic update in schedule()
@@ -12716,6 +12792,9 @@ static void task_fork_fair(struct task_struct *p)
 	curr = cfs_rq->curr;
 	if (curr)
 		update_curr(cfs_rq);
+#ifdef CONFIG_SCHED_BORE
+	update_burst_score(se);
+#endif // CONFIG_SCHED_BORE
 	place_entity(cfs_rq, se, ENQUEUE_INITIAL);
 	rq_unlock(rq, &rf);
 }
@@ -12828,6 +12907,10 @@ static void attach_task_cfs_rq(struct task_struct *p)
 
 static void switched_from_fair(struct rq *rq, struct task_struct *p)
 {
+	p->se.rel_deadline = 0;
+#ifdef CONFIG_SCHED_BORE
+	init_task_bore(p);
+#endif // CONFIG_SCHED_BORE
 	detach_task_cfs_rq(p);
 }
 
diff --git a/kernel/sched/features.h b/kernel/sched/features.h
index 143f55df89..e97b7b68bd 100644
--- a/kernel/sched/features.h
+++ b/kernel/sched/features.h
@@ -6,6 +6,10 @@
  */
 SCHED_FEAT(PLACE_LAG, true)
 SCHED_FEAT(PLACE_DEADLINE_INITIAL, true)
+/*
+ * Preserve relative virtual deadline on 'migration'.
+ */
+SCHED_FEAT(PLACE_REL_DEADLINE, true)
 SCHED_FEAT(RUN_TO_PARITY, true)
 
 /*
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 4c36cc6803..cc18ad228e 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1984,7 +1984,11 @@ static inline void update_sched_domain_debugfs(void) { }
 static inline void dirty_sched_domain_sysctl(int cpu) { }
 #endif
 
+#ifdef CONFIG_SCHED_BORE
+extern void sched_update_min_base_slice(void);
+#else // !CONFIG_SCHED_BORE
 extern int sched_update_scaling(void);
+#endif // CONFIG_SCHED_BORE
 
 static inline const struct cpumask *task_user_cpus(struct task_struct *p)
 {
@@ -2601,6 +2605,9 @@ extern const_debug unsigned int sysctl_sched_nr_migrate;
 extern const_debug unsigned int sysctl_sched_migration_cost;
 
 extern unsigned int sysctl_sched_base_slice;
+#ifdef CONFIG_SCHED_BORE
+extern unsigned int sysctl_sched_min_base_slice;
+#endif // CONFIG_SCHED_BORE
 
 #ifdef CONFIG_SCHED_DEBUG
 extern int sysctl_resched_latency_warn_ms;
-- 
2.34.1