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-rw-r--r--kernel/sched_fair.c118
1 files changed, 65 insertions, 53 deletions
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 433491c2dc8f..bc8ee9993814 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -135,14 +135,6 @@ static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
return grp->my_q;
}
-/* Given a group's cfs_rq on one cpu, return its corresponding cfs_rq on
- * another cpu ('this_cpu')
- */
-static inline struct cfs_rq *cpu_cfs_rq(struct cfs_rq *cfs_rq, int this_cpu)
-{
- return cfs_rq->tg->cfs_rq[this_cpu];
-}
-
static inline void list_add_leaf_cfs_rq(struct cfs_rq *cfs_rq)
{
if (!cfs_rq->on_list) {
@@ -271,11 +263,6 @@ static inline struct cfs_rq *group_cfs_rq(struct sched_entity *grp)
return NULL;
}
-static inline struct cfs_rq *cpu_cfs_rq(struct cfs_rq *cfs_rq, int this_cpu)
-{
- return &cpu_rq(this_cpu)->cfs;
-}
-
static inline void list_add_leaf_cfs_rq(struct cfs_rq *cfs_rq)
{
}
@@ -334,11 +321,6 @@ static inline int entity_before(struct sched_entity *a,
return (s64)(a->vruntime - b->vruntime) < 0;
}
-static inline s64 entity_key(struct cfs_rq *cfs_rq, struct sched_entity *se)
-{
- return se->vruntime - cfs_rq->min_vruntime;
-}
-
static void update_min_vruntime(struct cfs_rq *cfs_rq)
{
u64 vruntime = cfs_rq->min_vruntime;
@@ -372,7 +354,6 @@ static void __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
struct rb_node **link = &cfs_rq->tasks_timeline.rb_node;
struct rb_node *parent = NULL;
struct sched_entity *entry;
- s64 key = entity_key(cfs_rq, se);
int leftmost = 1;
/*
@@ -385,7 +366,7 @@ static void __enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
* We dont care about collisions. Nodes with
* the same key stay together.
*/
- if (key < entity_key(cfs_rq, entry)) {
+ if (entity_before(se, entry)) {
link = &parent->rb_left;
} else {
link = &parent->rb_right;
@@ -1336,7 +1317,7 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags)
}
for_each_sched_entity(se) {
- struct cfs_rq *cfs_rq = cfs_rq_of(se);
+ cfs_rq = cfs_rq_of(se);
update_cfs_load(cfs_rq, 0);
update_cfs_shares(cfs_rq);
@@ -1370,13 +1351,16 @@ static void dequeue_task_fair(struct rq *rq, struct task_struct *p, int flags)
*/
if (task_sleep && parent_entity(se))
set_next_buddy(parent_entity(se));
+
+ /* avoid re-evaluating load for this entity */
+ se = parent_entity(se);
break;
}
flags |= DEQUEUE_SLEEP;
}
for_each_sched_entity(se) {
- struct cfs_rq *cfs_rq = cfs_rq_of(se);
+ cfs_rq = cfs_rq_of(se);
update_cfs_load(cfs_rq, 0);
update_cfs_shares(cfs_rq);
@@ -1481,7 +1465,6 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync)
* effect of the currently running task from the load
* of the current CPU:
*/
- rcu_read_lock();
if (sync) {
tg = task_group(current);
weight = current->se.load.weight;
@@ -1517,7 +1500,6 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync)
balanced = this_eff_load <= prev_eff_load;
} else
balanced = true;
- rcu_read_unlock();
/*
* If the currently running task will sleep within
@@ -1585,7 +1567,7 @@ find_idlest_group(struct sched_domain *sd, struct task_struct *p,
}
/* Adjust by relative CPU power of the group */
- avg_load = (avg_load * SCHED_POWER_SCALE) / group->cpu_power;
+ avg_load = (avg_load * SCHED_POWER_SCALE) / group->sgp->power;
if (local_group) {
this_load = avg_load;
@@ -1921,8 +1903,8 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_
if (!sched_feat(WAKEUP_PREEMPT))
return;
- update_curr(cfs_rq);
find_matching_se(&se, &pse);
+ update_curr(cfs_rq_of(se));
BUG_ON(!pse);
if (wakeup_preempt_entity(se, pse) == 1) {
/*
@@ -2231,11 +2213,43 @@ static void update_shares(int cpu)
struct rq *rq = cpu_rq(cpu);
rcu_read_lock();
+ /*
+ * Iterates the task_group tree in a bottom up fashion, see
+ * list_add_leaf_cfs_rq() for details.
+ */
for_each_leaf_cfs_rq(rq, cfs_rq)
update_shares_cpu(cfs_rq->tg, cpu);
rcu_read_unlock();
}
+/*
+ * Compute the cpu's hierarchical load factor for each task group.
+ * This needs to be done in a top-down fashion because the load of a child
+ * group is a fraction of its parents load.
+ */
+static int tg_load_down(struct task_group *tg, void *data)
+{
+ unsigned long load;
+ long cpu = (long)data;
+
+ if (!tg->parent) {
+ load = cpu_rq(cpu)->load.weight;
+ } else {
+ load = tg->parent->cfs_rq[cpu]->h_load;
+ load *= tg->se[cpu]->load.weight;
+ load /= tg->parent->cfs_rq[cpu]->load.weight + 1;
+ }
+
+ tg->cfs_rq[cpu]->h_load = load;
+
+ return 0;
+}
+
+static void update_h_load(long cpu)
+{
+ walk_tg_tree(tg_load_down, tg_nop, (void *)cpu);
+}
+
static unsigned long
load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
unsigned long max_load_move,
@@ -2243,14 +2257,12 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest,
int *all_pinned)
{
long rem_load_move = max_load_move;
- int busiest_cpu = cpu_of(busiest);
- struct task_group *tg;
+ struct cfs_rq *busiest_cfs_rq;
rcu_read_lock();
- update_h_load(busiest_cpu);
+ update_h_load(cpu_of(busiest));
- list_for_each_entry_rcu(tg, &task_groups, list) {
- struct cfs_rq *busiest_cfs_rq = tg->cfs_rq[busiest_cpu];
+ for_each_leaf_cfs_rq(busiest, busiest_cfs_rq) {
unsigned long busiest_h_load = busiest_cfs_rq->h_load;
unsigned long busiest_weight = busiest_cfs_rq->load.weight;
u64 rem_load, moved_load;
@@ -2631,7 +2643,7 @@ static void update_cpu_power(struct sched_domain *sd, int cpu)
power >>= SCHED_POWER_SHIFT;
}
- sdg->cpu_power_orig = power;
+ sdg->sgp->power_orig = power;
if (sched_feat(ARCH_POWER))
power *= arch_scale_freq_power(sd, cpu);
@@ -2647,7 +2659,7 @@ static void update_cpu_power(struct sched_domain *sd, int cpu)
power = 1;
cpu_rq(cpu)->cpu_power = power;
- sdg->cpu_power = power;
+ sdg->sgp->power = power;
}
static void update_group_power(struct sched_domain *sd, int cpu)
@@ -2665,11 +2677,11 @@ static void update_group_power(struct sched_domain *sd, int cpu)
group = child->groups;
do {
- power += group->cpu_power;
+ power += group->sgp->power;
group = group->next;
} while (group != child->groups);
- sdg->cpu_power = power;
+ sdg->sgp->power = power;
}
/*
@@ -2691,7 +2703,7 @@ fix_small_capacity(struct sched_domain *sd, struct sched_group *group)
/*
* If ~90% of the cpu_power is still there, we're good.
*/
- if (group->cpu_power * 32 > group->cpu_power_orig * 29)
+ if (group->sgp->power * 32 > group->sgp->power_orig * 29)
return 1;
return 0;
@@ -2771,7 +2783,7 @@ static inline void update_sg_lb_stats(struct sched_domain *sd,
}
/* Adjust by relative CPU power of the group */
- sgs->avg_load = (sgs->group_load*SCHED_POWER_SCALE) / group->cpu_power;
+ sgs->avg_load = (sgs->group_load*SCHED_POWER_SCALE) / group->sgp->power;
/*
* Consider the group unbalanced when the imbalance is larger
@@ -2788,7 +2800,7 @@ static inline void update_sg_lb_stats(struct sched_domain *sd,
if ((max_cpu_load - min_cpu_load) >= avg_load_per_task && max_nr_running > 1)
sgs->group_imb = 1;
- sgs->group_capacity = DIV_ROUND_CLOSEST(group->cpu_power,
+ sgs->group_capacity = DIV_ROUND_CLOSEST(group->sgp->power,
SCHED_POWER_SCALE);
if (!sgs->group_capacity)
sgs->group_capacity = fix_small_capacity(sd, group);
@@ -2877,7 +2889,7 @@ static inline void update_sd_lb_stats(struct sched_domain *sd, int this_cpu,
return;
sds->total_load += sgs.group_load;
- sds->total_pwr += sg->cpu_power;
+ sds->total_pwr += sg->sgp->power;
/*
* In case the child domain prefers tasks go to siblings
@@ -2962,7 +2974,7 @@ static int check_asym_packing(struct sched_domain *sd,
if (this_cpu > busiest_cpu)
return 0;
- *imbalance = DIV_ROUND_CLOSEST(sds->max_load * sds->busiest->cpu_power,
+ *imbalance = DIV_ROUND_CLOSEST(sds->max_load * sds->busiest->sgp->power,
SCHED_POWER_SCALE);
return 1;
}
@@ -2993,7 +3005,7 @@ static inline void fix_small_imbalance(struct sd_lb_stats *sds,
scaled_busy_load_per_task = sds->busiest_load_per_task
* SCHED_POWER_SCALE;
- scaled_busy_load_per_task /= sds->busiest->cpu_power;
+ scaled_busy_load_per_task /= sds->busiest->sgp->power;
if (sds->max_load - sds->this_load + scaled_busy_load_per_task >=
(scaled_busy_load_per_task * imbn)) {
@@ -3007,28 +3019,28 @@ static inline void fix_small_imbalance(struct sd_lb_stats *sds,
* moving them.
*/
- pwr_now += sds->busiest->cpu_power *
+ pwr_now += sds->busiest->sgp->power *
min(sds->busiest_load_per_task, sds->max_load);
- pwr_now += sds->this->cpu_power *
+ pwr_now += sds->this->sgp->power *
min(sds->this_load_per_task, sds->this_load);
pwr_now /= SCHED_POWER_SCALE;
/* Amount of load we'd subtract */
tmp = (sds->busiest_load_per_task * SCHED_POWER_SCALE) /
- sds->busiest->cpu_power;
+ sds->busiest->sgp->power;
if (sds->max_load > tmp)
- pwr_move += sds->busiest->cpu_power *
+ pwr_move += sds->busiest->sgp->power *
min(sds->busiest_load_per_task, sds->max_load - tmp);
/* Amount of load we'd add */
- if (sds->max_load * sds->busiest->cpu_power <
+ if (sds->max_load * sds->busiest->sgp->power <
sds->busiest_load_per_task * SCHED_POWER_SCALE)
- tmp = (sds->max_load * sds->busiest->cpu_power) /
- sds->this->cpu_power;
+ tmp = (sds->max_load * sds->busiest->sgp->power) /
+ sds->this->sgp->power;
else
tmp = (sds->busiest_load_per_task * SCHED_POWER_SCALE) /
- sds->this->cpu_power;
- pwr_move += sds->this->cpu_power *
+ sds->this->sgp->power;
+ pwr_move += sds->this->sgp->power *
min(sds->this_load_per_task, sds->this_load + tmp);
pwr_move /= SCHED_POWER_SCALE;
@@ -3074,7 +3086,7 @@ static inline void calculate_imbalance(struct sd_lb_stats *sds, int this_cpu,
load_above_capacity *= (SCHED_LOAD_SCALE * SCHED_POWER_SCALE);
- load_above_capacity /= sds->busiest->cpu_power;
+ load_above_capacity /= sds->busiest->sgp->power;
}
/*
@@ -3090,8 +3102,8 @@ static inline void calculate_imbalance(struct sd_lb_stats *sds, int this_cpu,
max_pull = min(sds->max_load - sds->avg_load, load_above_capacity);
/* How much load to actually move to equalise the imbalance */
- *imbalance = min(max_pull * sds->busiest->cpu_power,
- (sds->avg_load - sds->this_load) * sds->this->cpu_power)
+ *imbalance = min(max_pull * sds->busiest->sgp->power,
+ (sds->avg_load - sds->this_load) * sds->this->sgp->power)
/ SCHED_POWER_SCALE;
/*
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.