if (!initial) {
/* sleeps upto a single latency don't count. */
- if (sched_feat(NEW_FAIR_SLEEPERS)) {
+ if (sched_feat(FAIR_SLEEPERS)) {
unsigned long thresh = sysctl_sched_latency;
/*
task_of(se)->policy != SCHED_IDLE))
thresh = calc_delta_fair(thresh, se);
+ /*
+ * Halve their sleep time's effect, to allow
+ * for a gentler effect of sleepers:
+ */
+ if (sched_feat(GENTLE_FAIR_SLEEPERS))
+ thresh >>= 1;
+
vruntime -= thresh;
}
}
static void __clear_buddies(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
- if (cfs_rq->last == se)
+ if (!se || cfs_rq->last == se)
cfs_rq->last = NULL;
- if (cfs_rq->next == se)
+ if (!se || cfs_rq->next == se)
cfs_rq->next = NULL;
}
load = source_load(prev_cpu, idx);
this_load = target_load(this_cpu, idx);
- if (sync && (curr->se.avg_overlap > sysctl_sched_migration_cost ||
- p->se.avg_overlap > sysctl_sched_migration_cost))
- sync = 0;
+ if (sync) {
+ if (sched_feat(SYNC_LESS) &&
+ (curr->se.avg_overlap > sysctl_sched_migration_cost ||
+ p->se.avg_overlap > sysctl_sched_migration_cost))
+ sync = 0;
+ } else {
+ if (sched_feat(SYNC_MORE) &&
+ (curr->se.avg_overlap < sysctl_sched_migration_cost &&
+ p->se.avg_overlap < sysctl_sched_migration_cost))
+ sync = 1;
+ }
/*
* If sync wakeup then subtract the (maximum possible)
* domain.
*/
static struct sched_group *
-find_idlest_group(struct sched_domain *sd, struct task_struct *p, int this_cpu)
+find_idlest_group(struct sched_domain *sd, struct task_struct *p,
+ int this_cpu, int load_idx)
{
struct sched_group *idlest = NULL, *this = NULL, *group = sd->groups;
unsigned long min_load = ULONG_MAX, this_load = 0;
- int load_idx = sd->forkexec_idx;
int imbalance = 100 + (sd->imbalance_pct-100)/2;
do {
*
* preempt must be disabled.
*/
-static int select_task_rq_fair(struct task_struct *p, int flag, int sync)
+static int select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flags)
{
- struct task_struct *t = current;
- struct sched_domain *tmp, *sd = NULL;
+ struct sched_domain *tmp, *affine_sd = NULL, *sd = NULL;
int cpu = smp_processor_id();
int prev_cpu = task_cpu(p);
int new_cpu = cpu;
int want_affine = 0;
+ int want_sd = 1;
+ int sync = wake_flags & WF_SYNC;
- if (flag & SD_BALANCE_WAKE) {
+ if (sd_flag & SD_BALANCE_WAKE) {
if (sched_feat(AFFINE_WAKEUPS))
want_affine = 1;
new_cpu = prev_cpu;
* If power savings logic is enabled for a domain, see if we
* are not overloaded, if so, don't balance wider.
*/
- if (tmp->flags & SD_POWERSAVINGS_BALANCE) {
+ if (tmp->flags & (SD_POWERSAVINGS_BALANCE|SD_PREFER_LOCAL)) {
unsigned long power = 0;
unsigned long nr_running = 0;
unsigned long capacity;
capacity = DIV_ROUND_CLOSEST(power, SCHED_LOAD_SCALE);
- if (nr_running/2 < capacity)
- break;
- }
+ if (tmp->flags & SD_POWERSAVINGS_BALANCE)
+ nr_running /= 2;
- switch (flag) {
- case SD_BALANCE_WAKE:
- if (!sched_feat(LB_WAKEUP_UPDATE))
- break;
- case SD_BALANCE_FORK:
- case SD_BALANCE_EXEC:
- if (root_task_group_empty())
- break;
- update_shares(tmp);
- default:
- break;
+ if (nr_running < capacity)
+ want_sd = 0;
}
if (want_affine && (tmp->flags & SD_WAKE_AFFINE) &&
cpumask_test_cpu(prev_cpu, sched_domain_span(tmp))) {
- if (wake_affine(tmp, p, sync)) {
- new_cpu = cpu;
- goto out;
- }
-
+ affine_sd = tmp;
want_affine = 0;
}
- if (!(tmp->flags & flag))
+ if (!want_sd && !want_affine)
+ break;
+
+ if (!(tmp->flags & sd_flag))
continue;
- sd = tmp;
+ if (want_sd)
+ sd = tmp;
+ }
+
+ if (sched_feat(LB_SHARES_UPDATE)) {
+ /*
+ * Pick the largest domain to update shares over
+ */
+ tmp = sd;
+ if (affine_sd && (!tmp ||
+ cpumask_weight(sched_domain_span(affine_sd)) >
+ cpumask_weight(sched_domain_span(sd))))
+ tmp = affine_sd;
+
+ if (tmp)
+ update_shares(tmp);
+ }
+
+ if (affine_sd && wake_affine(affine_sd, p, sync)) {
+ new_cpu = cpu;
+ goto out;
}
while (sd) {
+ int load_idx = sd->forkexec_idx;
struct sched_group *group;
int weight;
- if (!(sd->flags & flag)) {
+ if (!(sd->flags & sd_flag)) {
sd = sd->child;
continue;
}
- group = find_idlest_group(sd, t, cpu);
+ if (sd_flag & SD_BALANCE_WAKE)
+ load_idx = sd->wake_idx;
+
+ group = find_idlest_group(sd, p, cpu, load_idx);
if (!group) {
sd = sd->child;
continue;
}
- new_cpu = find_idlest_cpu(group, t, cpu);
+ new_cpu = find_idlest_cpu(group, p, cpu);
if (new_cpu == -1 || new_cpu == cpu) {
/* Now try balancing at a lower domain level of cpu */
sd = sd->child;
for_each_domain(cpu, tmp) {
if (weight <= cpumask_weight(sched_domain_span(tmp)))
break;
- if (tmp->flags & flag)
+ if (tmp->flags & sd_flag)
sd = tmp;
}
/* while loop will break here if sd == NULL */
/*
* Preempt the current task with a newly woken task if needed:
*/
-static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int sync)
+static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_flags)
{
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 sync = wake_flags & WF_SYNC;
update_curr(cfs_rq);
*/
if (sched_feat(LAST_BUDDY) && likely(se->on_rq && curr != rq->idle))
set_last_buddy(se);
- if (sched_feat(NEXT_BUDDY))
+ if (sched_feat(NEXT_BUDDY) && !(wake_flags & WF_FORK))
set_next_buddy(pse);
/*
return;
}
- if (!sched_feat(WAKEUP_PREEMPT))
- return;
-
if ((sched_feat(WAKEUP_SYNC) && sync) ||
(sched_feat(WAKEUP_OVERLAP) &&
(se->avg_overlap < sysctl_sched_migration_cost &&
return;
}
+ if (sched_feat(WAKEUP_RUNNING)) {
+ if (pse->avg_running < se->avg_running) {
+ set_next_buddy(pse);
+ resched_task(curr);
+ return;
+ }
+ }
+
+ if (!sched_feat(WAKEUP_PREEMPT))
+ return;
+
find_matching_se(&se, &pse);
BUG_ON(!pse);
/*
* If se was a buddy, clear it so that it will have to earn
* the favour again.
+ *
+ * If se was not a buddy, clear the buddies because neither
+ * was elegible to run, let them earn it again.
+ *
+ * IOW. unconditionally clear buddies.
*/
- __clear_buddies(cfs_rq, se);
+ __clear_buddies(cfs_rq, NULL);
set_next_entity(cfs_rq, se);
cfs_rq = group_cfs_rq(se);
} while (cfs_rq);