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-rw-r--r--kernel/sched/fair.c115
1 files changed, 82 insertions, 33 deletions
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index dffb270..7f0a5e6 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2032,6 +2032,7 @@ entity_tick(struct cfs_rq *cfs_rq, struct sched_entity *curr, int queued)
*/
update_entity_load_avg(curr, 1);
update_cfs_rq_blocked_load(cfs_rq, 1);
+ update_cfs_shares(cfs_rq);
#ifdef CONFIG_SCHED_HRTICK
/*
@@ -3017,6 +3018,23 @@ static unsigned long cpu_avg_load_per_task(int cpu)
return 0;
}
+static void record_wakee(struct task_struct *p)
+{
+ /*
+ * Rough decay (wiping) for cost saving, don't worry
+ * about the boundary, really active task won't care
+ * about the loss.
+ */
+ if (jiffies > current->wakee_flip_decay_ts + HZ) {
+ current->wakee_flips = 0;
+ current->wakee_flip_decay_ts = jiffies;
+ }
+
+ if (current->last_wakee != p) {
+ current->last_wakee = p;
+ current->wakee_flips++;
+ }
+}
static void task_waking_fair(struct task_struct *p)
{
@@ -3037,6 +3055,7 @@ static void task_waking_fair(struct task_struct *p)
#endif
se->vruntime -= min_vruntime;
+ record_wakee(p);
}
#ifdef CONFIG_FAIR_GROUP_SCHED
@@ -3155,6 +3174,28 @@ static inline unsigned long effective_load(struct task_group *tg, int cpu,
#endif
+static int wake_wide(struct task_struct *p)
+{
+ int factor = this_cpu_read(sd_llc_size);
+
+ /*
+ * Yeah, it's the switching-frequency, could means many wakee or
+ * rapidly switch, use factor here will just help to automatically
+ * adjust the loose-degree, so bigger node will lead to more pull.
+ */
+ if (p->wakee_flips > factor) {
+ /*
+ * wakee is somewhat hot, it needs certain amount of cpu
+ * resource, so if waker is far more hot, prefer to leave
+ * it alone.
+ */
+ if (current->wakee_flips > (factor * p->wakee_flips))
+ return 1;
+ }
+
+ return 0;
+}
+
static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync)
{
s64 this_load, load;
@@ -3164,6 +3205,13 @@ static int wake_affine(struct sched_domain *sd, struct task_struct *p, int sync)
unsigned long weight;
int balanced;
+ /*
+ * If we wake multiple tasks be careful to not bounce
+ * ourselves around too much.
+ */
+ if (wake_wide(p))
+ return 0;
+
idx = sd->wake_idx;
this_cpu = smp_processor_id();
prev_cpu = task_cpu(p);
@@ -4171,47 +4219,48 @@ static void update_blocked_averages(int cpu)
}
/*
- * Compute the cpu's hierarchical load factor for each task group.
+ * Compute the hierarchical load factor for cfs_rq and all its ascendants.
* 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)
+static void update_cfs_rq_h_load(struct cfs_rq *cfs_rq)
{
- unsigned long load;
- long cpu = (long)data;
-
- if (!tg->parent) {
- load = cpu_rq(cpu)->avg.load_avg_contrib;
- } else {
- load = tg->parent->cfs_rq[cpu]->h_load;
- load = div64_ul(load * tg->se[cpu]->avg.load_avg_contrib,
- tg->parent->cfs_rq[cpu]->runnable_load_avg + 1);
- }
-
- tg->cfs_rq[cpu]->h_load = load;
-
- return 0;
-}
-
-static void update_h_load(long cpu)
-{
- struct rq *rq = cpu_rq(cpu);
+ struct rq *rq = rq_of(cfs_rq);
+ struct sched_entity *se = cfs_rq->tg->se[cpu_of(rq)];
unsigned long now = jiffies;
+ unsigned long load;
- if (rq->h_load_throttle == now)
+ if (cfs_rq->last_h_load_update == now)
return;
- rq->h_load_throttle = now;
+ cfs_rq->h_load_next = NULL;
+ for_each_sched_entity(se) {
+ cfs_rq = cfs_rq_of(se);
+ cfs_rq->h_load_next = se;
+ if (cfs_rq->last_h_load_update == now)
+ break;
+ }
+
+ if (!se) {
+ cfs_rq->h_load = rq->avg.load_avg_contrib;
+ cfs_rq->last_h_load_update = now;
+ }
- rcu_read_lock();
- walk_tg_tree(tg_load_down, tg_nop, (void *)cpu);
- rcu_read_unlock();
+ while ((se = cfs_rq->h_load_next) != NULL) {
+ load = cfs_rq->h_load;
+ load = div64_ul(load * se->avg.load_avg_contrib,
+ cfs_rq->runnable_load_avg + 1);
+ cfs_rq = group_cfs_rq(se);
+ cfs_rq->h_load = load;
+ cfs_rq->last_h_load_update = now;
+ }
}
static unsigned long task_h_load(struct task_struct *p)
{
struct cfs_rq *cfs_rq = task_cfs_rq(p);
+ update_cfs_rq_h_load(cfs_rq);
return div64_ul(p->se.avg.load_avg_contrib * cfs_rq->h_load,
cfs_rq->runnable_load_avg + 1);
}
@@ -4220,10 +4269,6 @@ static inline void update_blocked_averages(int cpu)
{
}
-static inline void update_h_load(long cpu)
-{
-}
-
static unsigned long task_h_load(struct task_struct *p)
{
return p->se.avg.load_avg_contrib;
@@ -4286,6 +4331,8 @@ static inline void init_sd_lb_stats(struct sd_lb_stats *sds)
* get_sd_load_idx - Obtain the load index for a given sched domain.
* @sd: The sched_domain whose load_idx is to be obtained.
* @idle: The Idle status of the CPU for whose sd load_icx is obtained.
+ *
+ * Return: The load index.
*/
static inline int get_sd_load_idx(struct sched_domain *sd,
enum cpu_idle_type idle)
@@ -4611,6 +4658,9 @@ static inline void update_sg_lb_stats(struct lb_env *env,
*
* Determine if @sg is a busier group than the previously selected
* busiest group.
+ *
+ * Return: %true if @sg is a busier group than the previously selected
+ * busiest group. %false otherwise.
*/
static bool update_sd_pick_busiest(struct lb_env *env,
struct sd_lb_stats *sds,
@@ -4719,7 +4769,7 @@ static inline void update_sd_lb_stats(struct lb_env *env,
* assuming lower CPU number will be equivalent to lower a SMT thread
* number.
*
- * Returns 1 when packing is required and a task should be moved to
+ * Return: 1 when packing is required and a task should be moved to
* this CPU. The amount of the imbalance is returned in *imbalance.
*
* @env: The load balancing environment.
@@ -4904,7 +4954,7 @@ static inline void calculate_imbalance(struct lb_env *env, struct sd_lb_stats *s
*
* @env: The load balancing environment.
*
- * Returns: - the busiest group if imbalance exists.
+ * Return: - The busiest group if imbalance exists.
* - If no imbalance and user has opted for power-savings balance,
* return the least loaded group whose CPUs can be
* put to idle by rebalancing its tasks onto our group.
@@ -5174,7 +5224,6 @@ redo:
env.src_rq = busiest;
env.loop_max = min(sysctl_sched_nr_migrate, busiest->nr_running);
- update_h_load(env.src_cpu);
more_balance:
local_irq_save(flags);
double_rq_lock(env.dst_rq, busiest);