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Diffstat (limited to 'kernel/sched/core.c')
-rw-r--r--kernel/sched/core.c119
1 files changed, 69 insertions, 50 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 62671f53202a..f9123a82cbb6 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -306,6 +306,9 @@ __read_mostly int scheduler_running;
*/
int sysctl_sched_rt_runtime = 950000;
+/* cpus with isolated domains */
+cpumask_var_t cpu_isolated_map;
+
/*
* this_rq_lock - lock this runqueue and disable interrupts.
*/
@@ -690,6 +693,23 @@ static inline bool got_nohz_idle_kick(void)
bool sched_can_stop_tick(void)
{
/*
+ * FIFO realtime policy runs the highest priority task. Other runnable
+ * tasks are of a lower priority. The scheduler tick does nothing.
+ */
+ if (current->policy == SCHED_FIFO)
+ return true;
+
+ /*
+ * Round-robin realtime tasks time slice with other tasks at the same
+ * realtime priority. Is this task the only one at this priority?
+ */
+ if (current->policy == SCHED_RR) {
+ struct sched_rt_entity *rt_se = &current->rt;
+
+ return rt_se->run_list.prev == rt_se->run_list.next;
+ }
+
+ /*
* More than one running task need preemption.
* nr_running update is assumed to be visible
* after IPI is sent from wakers.
@@ -996,6 +1016,13 @@ void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags)
rq_clock_skip_update(rq, true);
}
+static ATOMIC_NOTIFIER_HEAD(task_migration_notifier);
+
+void register_task_migration_notifier(struct notifier_block *n)
+{
+ atomic_notifier_chain_register(&task_migration_notifier, n);
+}
+
#ifdef CONFIG_SMP
void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
{
@@ -1026,10 +1053,18 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
trace_sched_migrate_task(p, new_cpu);
if (task_cpu(p) != new_cpu) {
+ struct task_migration_notifier tmn;
+
if (p->sched_class->migrate_task_rq)
p->sched_class->migrate_task_rq(p, new_cpu);
p->se.nr_migrations++;
perf_sw_event_sched(PERF_COUNT_SW_CPU_MIGRATIONS, 1, 0);
+
+ tmn.task = p;
+ tmn.from_cpu = task_cpu(p);
+ tmn.to_cpu = new_cpu;
+
+ atomic_notifier_call_chain(&task_migration_notifier, 0, &tmn);
}
__set_task_cpu(p, new_cpu);
@@ -2818,7 +2853,7 @@ asmlinkage __visible void __sched schedule_user(void)
* we find a better solution.
*
* NB: There are buggy callers of this function. Ideally we
- * should warn if prev_state != IN_USER, but that will trigger
+ * should warn if prev_state != CONTEXT_USER, but that will trigger
* too frequently to make sense yet.
*/
enum ctx_state prev_state = exception_enter();
@@ -5320,36 +5355,13 @@ static int sched_cpu_active(struct notifier_block *nfb,
static int sched_cpu_inactive(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
- unsigned long flags;
- long cpu = (long)hcpu;
- struct dl_bw *dl_b;
-
switch (action & ~CPU_TASKS_FROZEN) {
case CPU_DOWN_PREPARE:
- set_cpu_active(cpu, false);
-
- /* explicitly allow suspend */
- if (!(action & CPU_TASKS_FROZEN)) {
- bool overflow;
- int cpus;
-
- rcu_read_lock_sched();
- dl_b = dl_bw_of(cpu);
-
- raw_spin_lock_irqsave(&dl_b->lock, flags);
- cpus = dl_bw_cpus(cpu);
- overflow = __dl_overflow(dl_b, cpus, 0, 0);
- raw_spin_unlock_irqrestore(&dl_b->lock, flags);
-
- rcu_read_unlock_sched();
-
- if (overflow)
- return notifier_from_errno(-EBUSY);
- }
+ set_cpu_active((long)hcpu, false);
return NOTIFY_OK;
+ default:
+ return NOTIFY_DONE;
}
-
- return NOTIFY_DONE;
}
static int __init migration_init(void)
@@ -5430,17 +5442,6 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
break;
}
- /*
- * Even though we initialize ->capacity to something semi-sane,
- * we leave capacity_orig unset. This allows us to detect if
- * domain iteration is still funny without causing /0 traps.
- */
- if (!group->sgc->capacity_orig) {
- printk(KERN_CONT "\n");
- printk(KERN_ERR "ERROR: domain->cpu_capacity not set\n");
- break;
- }
-
if (!cpumask_weight(sched_group_cpus(group))) {
printk(KERN_CONT "\n");
printk(KERN_ERR "ERROR: empty group\n");
@@ -5813,9 +5814,6 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
update_top_cache_domain(cpu);
}
-/* cpus with isolated domains */
-static cpumask_var_t cpu_isolated_map;
-
/* Setup the mask of cpus configured for isolated domains */
static int __init isolated_cpu_setup(char *str)
{
@@ -5924,7 +5922,6 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
* die on a /0 trap.
*/
sg->sgc->capacity = SCHED_CAPACITY_SCALE * cpumask_weight(sg_span);
- sg->sgc->capacity_orig = sg->sgc->capacity;
/*
* Make sure the first group of this domain contains the
@@ -6235,6 +6232,7 @@ sd_init(struct sched_domain_topology_level *tl, int cpu)
*/
if (sd->flags & SD_SHARE_CPUCAPACITY) {
+ sd->flags |= SD_PREFER_SIBLING;
sd->imbalance_pct = 110;
sd->smt_gain = 1178; /* ~15% */
@@ -7000,7 +6998,6 @@ static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action,
*/
case CPU_ONLINE:
- case CPU_DOWN_FAILED:
cpuset_update_active_cpus(true);
break;
default:
@@ -7012,8 +7009,30 @@ static int cpuset_cpu_active(struct notifier_block *nfb, unsigned long action,
static int cpuset_cpu_inactive(struct notifier_block *nfb, unsigned long action,
void *hcpu)
{
- switch (action) {
+ unsigned long flags;
+ long cpu = (long)hcpu;
+ struct dl_bw *dl_b;
+
+ switch (action & ~CPU_TASKS_FROZEN) {
case CPU_DOWN_PREPARE:
+ /* explicitly allow suspend */
+ if (!(action & CPU_TASKS_FROZEN)) {
+ bool overflow;
+ int cpus;
+
+ rcu_read_lock_sched();
+ dl_b = dl_bw_of(cpu);
+
+ raw_spin_lock_irqsave(&dl_b->lock, flags);
+ cpus = dl_bw_cpus(cpu);
+ overflow = __dl_overflow(dl_b, cpus, 0, 0);
+ raw_spin_unlock_irqrestore(&dl_b->lock, flags);
+
+ rcu_read_unlock_sched();
+
+ if (overflow)
+ return notifier_from_errno(-EBUSY);
+ }
cpuset_update_active_cpus(false);
break;
case CPU_DOWN_PREPARE_FROZEN:
@@ -7158,8 +7177,8 @@ void __init sched_init(void)
rq->calc_load_active = 0;
rq->calc_load_update = jiffies + LOAD_FREQ;
init_cfs_rq(&rq->cfs);
- init_rt_rq(&rq->rt, rq);
- init_dl_rq(&rq->dl, rq);
+ init_rt_rq(&rq->rt);
+ init_dl_rq(&rq->dl);
#ifdef CONFIG_FAIR_GROUP_SCHED
root_task_group.shares = ROOT_TASK_GROUP_LOAD;
INIT_LIST_HEAD(&rq->leaf_cfs_rq_list);
@@ -7199,7 +7218,7 @@ void __init sched_init(void)
#ifdef CONFIG_SMP
rq->sd = NULL;
rq->rd = NULL;
- rq->cpu_capacity = SCHED_CAPACITY_SCALE;
+ rq->cpu_capacity = rq->cpu_capacity_orig = SCHED_CAPACITY_SCALE;
rq->post_schedule = 0;
rq->active_balance = 0;
rq->next_balance = jiffies;
@@ -7798,7 +7817,7 @@ static int sched_rt_global_constraints(void)
}
#endif /* CONFIG_RT_GROUP_SCHED */
-static int sched_dl_global_constraints(void)
+static int sched_dl_global_validate(void)
{
u64 runtime = global_rt_runtime();
u64 period = global_rt_period();
@@ -7899,11 +7918,11 @@ int sched_rt_handler(struct ctl_table *table, int write,
if (ret)
goto undo;
- ret = sched_rt_global_constraints();
+ ret = sched_dl_global_validate();
if (ret)
goto undo;
- ret = sched_dl_global_constraints();
+ ret = sched_rt_global_constraints();
if (ret)
goto undo;
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-15 16:13:16 +0300