[PATCH 1/5] sched/BT: add BT scheduling entity

From: xiaoggchen
Date: Fri Jun 21 2019 - 03:55:22 EST


From: chen xiaoguang <xiaoggchen@xxxxxxxxxxx>

Signed-off-by: Newton Gao <newtongao@xxxxxxxxxxx>
Signed-off-by: Shook Liu <shookliu@xxxxxxxxxxx>
Signed-off-by: Zhiguang Peng <zgpeng@xxxxxxxxxxx>
Signed-off-by: Xiaoguang Chen <xiaoggchen@xxxxxxxxxxx>
---
include/linux/sched.h | 18 ++++++++++++++++++
include/uapi/linux/sched.h | 1 +
kernel/sched/Makefile | 2 +-
kernel/sched/bt.c | 17 +++++++++++++++++
kernel/sched/core.c | 10 ++++++++++
kernel/sched/sched.h | 22 ++++++++++++++++++++++
6 files changed, 69 insertions(+), 1 deletion(-)
create mode 100644 kernel/sched/bt.c

diff --git a/include/linux/sched.h b/include/linux/sched.h
index 1183741..c0dfbb2 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -560,6 +560,23 @@ struct sched_dl_entity {
struct hrtimer inactive_timer;
};

+struct sched_bt_entity {
+ struct load_weight load;
+ struct rb_node run_node;
+ unsigned int on_rq;
+
+ u64 exec_start;
+ u64 sum_exec_runtime;
+ u64 vruntime;
+ u64 prev_sum_exec_runtime;
+
+ u64 nr_migrations;
+
+#if defined(CONFIG_SCHEDSTATS) || defined(CONFIG_LATENCYTOP)
+ struct sched_statistics *statistics;
+#endif
+};
+
union rcu_special {
struct {
u8 blocked;
@@ -639,6 +656,7 @@ struct task_struct {
struct task_group *sched_task_group;
#endif
struct sched_dl_entity dl;
+ struct sched_bt_entity bt;

#ifdef CONFIG_PREEMPT_NOTIFIERS
/* List of struct preempt_notifier: */
diff --git a/include/uapi/linux/sched.h b/include/uapi/linux/sched.h
index ed4ee17..410042a 100644
--- a/include/uapi/linux/sched.h
+++ b/include/uapi/linux/sched.h
@@ -41,6 +41,7 @@
/* SCHED_ISO: reserved but not implemented yet */
#define SCHED_IDLE 5
#define SCHED_DEADLINE 6
+#define SCHED_BT 7

/* Can be ORed in to make sure the process is reverted back to SCHED_NORMAL on fork */
#define SCHED_RESET_ON_FORK 0x40000000
diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile
index 21fb5a5..938e539 100644
--- a/kernel/sched/Makefile
+++ b/kernel/sched/Makefile
@@ -17,7 +17,7 @@ CFLAGS_core.o := $(PROFILING) -fno-omit-frame-pointer
endif

obj-y += core.o loadavg.o clock.o cputime.o
-obj-y += idle.o fair.o rt.o deadline.o
+obj-y += idle.o fair.o rt.o deadline.o bt.o
obj-y += wait.o wait_bit.o swait.o completion.o

obj-$(CONFIG_SMP) += cpupri.o cpudeadline.o topology.o stop_task.o pelt.o
diff --git a/kernel/sched/bt.c b/kernel/sched/bt.c
new file mode 100644
index 0000000..56566e6
--- /dev/null
+++ b/kernel/sched/bt.c
@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Background Scheduling Class
+ */
+
+#include "sched.h"
+
+void init_bt_rq(struct bt_rq *bt_rq)
+{
+ bt_rq->tasks_timeline = RB_ROOT;
+ bt_rq->min_vruntime = (u64)(-(1LL << 20));
+#ifndef CONFIG_64BIT
+ bt_rq->min_vruntime_copy = bt_rq->min_vruntime;
+#endif
+}
+
+
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 874c427..3eb4723 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2138,6 +2138,13 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p)
p->se.vruntime = 0;
INIT_LIST_HEAD(&p->se.group_node);

+ p->bt.on_rq = 0;
+ p->bt.exec_start = 0;
+ p->bt.sum_exec_runtime = 0;
+ p->bt.prev_sum_exec_runtime = 0;
+ p->bt.nr_migrations = 0;
+ p->bt.vruntime = 0;
+
#ifdef CONFIG_FAIR_GROUP_SCHED
p->se.cfs_rq = NULL;
#endif
@@ -2145,6 +2152,7 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p)
#ifdef CONFIG_SCHEDSTATS
/* Even if schedstat is disabled, there should not be garbage */
memset(&p->se.statistics, 0, sizeof(p->se.statistics));
+ p->bt.statistics = &p->se.statistics;
#endif

RB_CLEAR_NODE(&p->dl.rb_node);
@@ -5974,6 +5982,7 @@ void __init sched_init(void)
init_cfs_rq(&rq->cfs);
init_rt_rq(&rq->rt);
init_dl_rq(&rq->dl);
+ init_bt_rq(&rq->bt);
#ifdef CONFIG_FAIR_GROUP_SCHED
root_task_group.shares = ROOT_TASK_GROUP_LOAD;
INIT_LIST_HEAD(&rq->leaf_cfs_rq_list);
@@ -6186,6 +6195,7 @@ void normalize_rt_tasks(void)
continue;

p->se.exec_start = 0;
+ p->bt.exec_start = 0;
schedstat_set(p->se.statistics.wait_start, 0);
schedstat_set(p->se.statistics.sleep_start, 0);
schedstat_set(p->se.statistics.block_start, 0);
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index b52ed1a..320c80d 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -331,6 +331,7 @@ bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)

struct cfs_rq;
struct rt_rq;
+struct bt_rq;

extern struct list_head task_groups;

@@ -576,6 +577,25 @@ struct cfs_rq {
#endif /* CONFIG_FAIR_GROUP_SCHED */
};

+struct bt_rq {
+ struct load_weight load;
+ unsigned int bt_nr_running;
+ unsigned long nr_uninterruptible;
+
+ u64 exec_clock;
+ u64 min_vruntime;
+#ifndef CONFIG_64BIT
+ u64 min_vruntime_copy;
+#endif
+#ifdef CONFIG_SCHED_DEBUG
+ unsigned int nr_spread_over;
+#endif
+ struct rb_root tasks_timeline;
+ struct rb_node *rb_leftmost;
+
+ struct sched_bt_entity *curr, *next;
+};
+
static inline int rt_bandwidth_enabled(void)
{
return sysctl_sched_rt_runtime >= 0;
@@ -838,6 +858,7 @@ struct rq {
struct cfs_rq cfs;
struct rt_rq rt;
struct dl_rq dl;
+ struct bt_rq bt;

#ifdef CONFIG_FAIR_GROUP_SCHED
/* list of leaf cfs_rq on this CPU: */
@@ -2107,6 +2128,7 @@ static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
extern void init_cfs_rq(struct cfs_rq *cfs_rq);
extern void init_rt_rq(struct rt_rq *rt_rq);
extern void init_dl_rq(struct dl_rq *dl_rq);
+extern void init_bt_rq(struct bt_rq *bt_rq);

extern void cfs_bandwidth_usage_inc(void);
extern void cfs_bandwidth_usage_dec(void);
--
1.8.3.1