[PATCH 1/3] sched/deadline: move dl related code out of sched/core.c

From: Nicolas Pitre
Date: Wed Jun 21 2017 - 14:31:37 EST


... to sched/deadline.c. This helps making sched/core.c smaller and
hopefully easier to understand and maintain.

Signed-off-by: Nicolas Pitre <nico@xxxxxxxxxx>
---
kernel/sched/core.c | 343 +----------------------------------------------
kernel/sched/deadline.c | 344 ++++++++++++++++++++++++++++++++++++++++++++++++
kernel/sched/sched.h | 17 ++-
3 files changed, 364 insertions(+), 340 deletions(-)

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 7faf4b322b..54e1b0700a 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2140,25 +2140,6 @@ int wake_up_state(struct task_struct *p, unsigned int state)
}

/*
- * This function clears the sched_dl_entity static params.
- */
-void __dl_clear_params(struct task_struct *p)
-{
- struct sched_dl_entity *dl_se = &p->dl;
-
- dl_se->dl_runtime = 0;
- dl_se->dl_deadline = 0;
- dl_se->dl_period = 0;
- dl_se->flags = 0;
- dl_se->dl_bw = 0;
- dl_se->dl_density = 0;
-
- dl_se->dl_throttled = 0;
- dl_se->dl_yielded = 0;
- dl_se->dl_non_contending = 0;
-}
-
-/*
* Perform scheduler related setup for a newly forked process p.
* p is forked by current.
*
@@ -2438,101 +2419,6 @@ unsigned long to_ratio(u64 period, u64 runtime)
return div64_u64(runtime << BW_SHIFT, period);
}

-#ifdef CONFIG_SMP
-inline struct dl_bw *dl_bw_of(int i)
-{
- RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
- "sched RCU must be held");
- return &cpu_rq(i)->rd->dl_bw;
-}
-
-inline int dl_bw_cpus(int i)
-{
- struct root_domain *rd = cpu_rq(i)->rd;
- int cpus = 0;
-
- RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
- "sched RCU must be held");
- for_each_cpu_and(i, rd->span, cpu_active_mask)
- cpus++;
-
- return cpus;
-}
-#else
-inline struct dl_bw *dl_bw_of(int i)
-{
- return &cpu_rq(i)->dl.dl_bw;
-}
-
-inline int dl_bw_cpus(int i)
-{
- return 1;
-}
-#endif
-
-/*
- * We must be sure that accepting a new task (or allowing changing the
- * parameters of an existing one) is consistent with the bandwidth
- * constraints. If yes, this function also accordingly updates the currently
- * allocated bandwidth to reflect the new situation.
- *
- * This function is called while holding p's rq->lock.
- */
-static int dl_overflow(struct task_struct *p, int policy,
- const struct sched_attr *attr)
-{
-
- struct dl_bw *dl_b = dl_bw_of(task_cpu(p));
- u64 period = attr->sched_period ?: attr->sched_deadline;
- u64 runtime = attr->sched_runtime;
- u64 new_bw = dl_policy(policy) ? to_ratio(period, runtime) : 0;
- int cpus, err = -1;
-
- /* !deadline task may carry old deadline bandwidth */
- if (new_bw == p->dl.dl_bw && task_has_dl_policy(p))
- return 0;
-
- /*
- * Either if a task, enters, leave, or stays -deadline but changes
- * its parameters, we may need to update accordingly the total
- * allocated bandwidth of the container.
- */
- raw_spin_lock(&dl_b->lock);
- cpus = dl_bw_cpus(task_cpu(p));
- if (dl_policy(policy) && !task_has_dl_policy(p) &&
- !__dl_overflow(dl_b, cpus, 0, new_bw)) {
- if (hrtimer_active(&p->dl.inactive_timer))
- __dl_clear(dl_b, p->dl.dl_bw, cpus);
- __dl_add(dl_b, new_bw, cpus);
- err = 0;
- } else if (dl_policy(policy) && task_has_dl_policy(p) &&
- !__dl_overflow(dl_b, cpus, p->dl.dl_bw, new_bw)) {
- /*
- * XXX this is slightly incorrect: when the task
- * utilization decreases, we should delay the total
- * utilization change until the task's 0-lag point.
- * But this would require to set the task's "inactive
- * timer" when the task is not inactive.
- */
- __dl_clear(dl_b, p->dl.dl_bw, cpus);
- __dl_add(dl_b, new_bw, cpus);
- dl_change_utilization(p, new_bw);
- err = 0;
- } else if (!dl_policy(policy) && task_has_dl_policy(p)) {
- /*
- * Do not decrease the total deadline utilization here,
- * switched_from_dl() will take care to do it at the correct
- * (0-lag) time.
- */
- err = 0;
- }
- raw_spin_unlock(&dl_b->lock);
-
- return err;
-}
-
-extern void init_dl_bw(struct dl_bw *dl_b);
-
/*
* wake_up_new_task - wake up a newly created task for the first time.
*
@@ -4015,27 +3901,6 @@ static struct task_struct *find_process_by_pid(pid_t pid)
}

/*
- * This function initializes the sched_dl_entity of a newly becoming
- * SCHED_DEADLINE task.
- *
- * Only the static values are considered here, the actual runtime and the
- * absolute deadline will be properly calculated when the task is enqueued
- * for the first time with its new policy.
- */
-static void
-__setparam_dl(struct task_struct *p, const struct sched_attr *attr)
-{
- struct sched_dl_entity *dl_se = &p->dl;
-
- dl_se->dl_runtime = attr->sched_runtime;
- dl_se->dl_deadline = attr->sched_deadline;
- dl_se->dl_period = attr->sched_period ?: dl_se->dl_deadline;
- dl_se->flags = attr->sched_flags;
- dl_se->dl_bw = to_ratio(dl_se->dl_period, dl_se->dl_runtime);
- dl_se->dl_density = to_ratio(dl_se->dl_deadline, dl_se->dl_runtime);
-}
-
-/*
* sched_setparam() passes in -1 for its policy, to let the functions
* it calls know not to change it.
*/
@@ -4088,59 +3953,6 @@ static void __setscheduler(struct rq *rq, struct task_struct *p,
p->sched_class = &fair_sched_class;
}

-static void
-__getparam_dl(struct task_struct *p, struct sched_attr *attr)
-{
- struct sched_dl_entity *dl_se = &p->dl;
-
- attr->sched_priority = p->rt_priority;
- attr->sched_runtime = dl_se->dl_runtime;
- attr->sched_deadline = dl_se->dl_deadline;
- attr->sched_period = dl_se->dl_period;
- attr->sched_flags = dl_se->flags;
-}
-
-/*
- * This function validates the new parameters of a -deadline task.
- * We ask for the deadline not being zero, and greater or equal
- * than the runtime, as well as the period of being zero or
- * greater than deadline. Furthermore, we have to be sure that
- * user parameters are above the internal resolution of 1us (we
- * check sched_runtime only since it is always the smaller one) and
- * below 2^63 ns (we have to check both sched_deadline and
- * sched_period, as the latter can be zero).
- */
-static bool
-__checkparam_dl(const struct sched_attr *attr)
-{
- /* deadline != 0 */
- if (attr->sched_deadline == 0)
- return false;
-
- /*
- * Since we truncate DL_SCALE bits, make sure we're at least
- * that big.
- */
- if (attr->sched_runtime < (1ULL << DL_SCALE))
- return false;
-
- /*
- * Since we use the MSB for wrap-around and sign issues, make
- * sure it's not set (mind that period can be equal to zero).
- */
- if (attr->sched_deadline & (1ULL << 63) ||
- attr->sched_period & (1ULL << 63))
- return false;
-
- /* runtime <= deadline <= period (if period != 0) */
- if ((attr->sched_period != 0 &&
- attr->sched_period < attr->sched_deadline) ||
- attr->sched_deadline < attr->sched_runtime)
- return false;
-
- return true;
-}
-
/*
* Check the target process has a UID that matches the current process's:
*/
@@ -4157,19 +3969,6 @@ static bool check_same_owner(struct task_struct *p)
return match;
}

-static bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr)
-{
- struct sched_dl_entity *dl_se = &p->dl;
-
- if (dl_se->dl_runtime != attr->sched_runtime ||
- dl_se->dl_deadline != attr->sched_deadline ||
- dl_se->dl_period != attr->sched_period ||
- dl_se->flags != attr->sched_flags)
- return true;
-
- return false;
-}
-
static int __sched_setscheduler(struct task_struct *p,
const struct sched_attr *attr,
bool user, bool pi)
@@ -4350,7 +4149,7 @@ static int __sched_setscheduler(struct task_struct *p,
* of a SCHED_DEADLINE task) we need to check if enough bandwidth
* is available.
*/
- if ((dl_policy(policy) || dl_task(p)) && dl_overflow(p, policy, attr)) {
+ if ((dl_policy(policy) || dl_task(p)) && sched_dl_overflow(p, policy, attr)) {
task_rq_unlock(rq, p, &rf);
return -EBUSY;
}
@@ -5456,23 +5255,12 @@ void init_idle(struct task_struct *idle, int cpu)
int cpuset_cpumask_can_shrink(const struct cpumask *cur,
const struct cpumask *trial)
{
- int ret = 1, trial_cpus;
- struct dl_bw *cur_dl_b;
- unsigned long flags;
+ int ret = 1;

if (!cpumask_weight(cur))
return ret;

- rcu_read_lock_sched();
- cur_dl_b = dl_bw_of(cpumask_any(cur));
- trial_cpus = cpumask_weight(trial);
-
- raw_spin_lock_irqsave(&cur_dl_b->lock, flags);
- if (cur_dl_b->bw != -1 &&
- cur_dl_b->bw * trial_cpus < cur_dl_b->total_bw)
- ret = 0;
- raw_spin_unlock_irqrestore(&cur_dl_b->lock, flags);
- rcu_read_unlock_sched();
+ ret = dl_cpuset_cpumask_can_shrink(cur, trial);

return ret;
}
@@ -5497,34 +5285,8 @@ int task_can_attach(struct task_struct *p,
}

if (dl_task(p) && !cpumask_intersects(task_rq(p)->rd->span,
- cs_cpus_allowed)) {
- unsigned int dest_cpu = cpumask_any_and(cpu_active_mask,
- cs_cpus_allowed);
- struct dl_bw *dl_b;
- bool overflow;
- int cpus;
- unsigned long flags;
-
- rcu_read_lock_sched();
- dl_b = dl_bw_of(dest_cpu);
- raw_spin_lock_irqsave(&dl_b->lock, flags);
- cpus = dl_bw_cpus(dest_cpu);
- overflow = __dl_overflow(dl_b, cpus, 0, p->dl.dl_bw);
- if (overflow)
- ret = -EBUSY;
- else {
- /*
- * We reserve space for this task in the destination
- * root_domain, as we can't fail after this point.
- * We will free resources in the source root_domain
- * later on (see set_cpus_allowed_dl()).
- */
- __dl_add(dl_b, p->dl.dl_bw, cpus);
- }
- raw_spin_unlock_irqrestore(&dl_b->lock, flags);
- rcu_read_unlock_sched();
-
- }
+ cs_cpus_allowed))
+ ret = dl_task_can_attach(p, cs_cpus_allowed);

out:
return ret;
@@ -5792,23 +5554,8 @@ static void cpuset_cpu_active(void)

static int cpuset_cpu_inactive(unsigned int cpu)
{
- unsigned long flags;
- struct dl_bw *dl_b;
- bool overflow;
- int cpus;
-
if (!cpuhp_tasks_frozen) {
- 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)
+ if (dl_cpu_busy(cpu))
return -EBUSY;
cpuset_update_active_cpus();
} else {
@@ -6711,84 +6458,6 @@ static int sched_rt_global_constraints(void)
}
#endif /* CONFIG_RT_GROUP_SCHED */

-static int sched_dl_global_validate(void)
-{
- u64 runtime = global_rt_runtime();
- u64 period = global_rt_period();
- u64 new_bw = to_ratio(period, runtime);
- struct dl_bw *dl_b;
- int cpu, ret = 0;
- unsigned long flags;
-
- /*
- * Here we want to check the bandwidth not being set to some
- * value smaller than the currently allocated bandwidth in
- * any of the root_domains.
- *
- * FIXME: Cycling on all the CPUs is overdoing, but simpler than
- * cycling on root_domains... Discussion on different/better
- * solutions is welcome!
- */
- for_each_possible_cpu(cpu) {
- rcu_read_lock_sched();
- dl_b = dl_bw_of(cpu);
-
- raw_spin_lock_irqsave(&dl_b->lock, flags);
- if (new_bw < dl_b->total_bw)
- ret = -EBUSY;
- raw_spin_unlock_irqrestore(&dl_b->lock, flags);
-
- rcu_read_unlock_sched();
-
- if (ret)
- break;
- }
-
- return ret;
-}
-
-void init_dl_rq_bw_ratio(struct dl_rq *dl_rq)
-{
- if (global_rt_runtime() == RUNTIME_INF) {
- dl_rq->bw_ratio = 1 << RATIO_SHIFT;
- dl_rq->extra_bw = 1 << BW_SHIFT;
- } else {
- dl_rq->bw_ratio = to_ratio(global_rt_runtime(),
- global_rt_period()) >> (BW_SHIFT - RATIO_SHIFT);
- dl_rq->extra_bw = to_ratio(global_rt_period(),
- global_rt_runtime());
- }
-}
-
-static void sched_dl_do_global(void)
-{
- u64 new_bw = -1;
- struct dl_bw *dl_b;
- int cpu;
- unsigned long flags;
-
- def_dl_bandwidth.dl_period = global_rt_period();
- def_dl_bandwidth.dl_runtime = global_rt_runtime();
-
- if (global_rt_runtime() != RUNTIME_INF)
- new_bw = to_ratio(global_rt_period(), global_rt_runtime());
-
- /*
- * FIXME: As above...
- */
- for_each_possible_cpu(cpu) {
- rcu_read_lock_sched();
- dl_b = dl_bw_of(cpu);
-
- raw_spin_lock_irqsave(&dl_b->lock, flags);
- dl_b->bw = new_bw;
- raw_spin_unlock_irqrestore(&dl_b->lock, flags);
-
- rcu_read_unlock_sched();
- init_dl_rq_bw_ratio(&cpu_rq(cpu)->dl);
- }
-}
-
static int sched_rt_global_validate(void)
{
if (sysctl_sched_rt_period <= 0)
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index e12f859758..a84299f44b 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -17,6 +17,7 @@
#include "sched.h"

#include <linux/slab.h>
+#include <uapi/linux/sched/types.h>

struct dl_bandwidth def_dl_bandwidth;

@@ -43,6 +44,38 @@ static inline int on_dl_rq(struct sched_dl_entity *dl_se)
return !RB_EMPTY_NODE(&dl_se->rb_node);
}

+#ifdef CONFIG_SMP
+static inline struct dl_bw *dl_bw_of(int i)
+{
+ RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
+ "sched RCU must be held");
+ return &cpu_rq(i)->rd->dl_bw;
+}
+
+static inline int dl_bw_cpus(int i)
+{
+ struct root_domain *rd = cpu_rq(i)->rd;
+ int cpus = 0;
+
+ RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
+ "sched RCU must be held");
+ for_each_cpu_and(i, rd->span, cpu_active_mask)
+ cpus++;
+
+ return cpus;
+}
+#else
+static inline struct dl_bw *dl_bw_of(int i)
+{
+ return &cpu_rq(i)->dl.dl_bw;
+}
+
+static inline int dl_bw_cpus(int i)
+{
+ return 1;
+}
+#endif
+
static inline
void add_running_bw(u64 dl_bw, struct dl_rq *dl_rq)
{
@@ -2318,6 +2351,317 @@ const struct sched_class dl_sched_class = {
.update_curr = update_curr_dl,
};

+int sched_dl_global_validate(void)
+{
+ u64 runtime = global_rt_runtime();
+ u64 period = global_rt_period();
+ u64 new_bw = to_ratio(period, runtime);
+ struct dl_bw *dl_b;
+ int cpu, ret = 0;
+ unsigned long flags;
+
+ /*
+ * Here we want to check the bandwidth not being set to some
+ * value smaller than the currently allocated bandwidth in
+ * any of the root_domains.
+ *
+ * FIXME: Cycling on all the CPUs is overdoing, but simpler than
+ * cycling on root_domains... Discussion on different/better
+ * solutions is welcome!
+ */
+ for_each_possible_cpu(cpu) {
+ rcu_read_lock_sched();
+ dl_b = dl_bw_of(cpu);
+
+ raw_spin_lock_irqsave(&dl_b->lock, flags);
+ if (new_bw < dl_b->total_bw)
+ ret = -EBUSY;
+ raw_spin_unlock_irqrestore(&dl_b->lock, flags);
+
+ rcu_read_unlock_sched();
+
+ if (ret)
+ break;
+ }
+
+ return ret;
+}
+
+void init_dl_rq_bw_ratio(struct dl_rq *dl_rq)
+{
+ if (global_rt_runtime() == RUNTIME_INF) {
+ dl_rq->bw_ratio = 1 << RATIO_SHIFT;
+ dl_rq->extra_bw = 1 << BW_SHIFT;
+ } else {
+ dl_rq->bw_ratio = to_ratio(global_rt_runtime(),
+ global_rt_period()) >> (BW_SHIFT - RATIO_SHIFT);
+ dl_rq->extra_bw = to_ratio(global_rt_period(),
+ global_rt_runtime());
+ }
+}
+
+void sched_dl_do_global(void)
+{
+ u64 new_bw = -1;
+ struct dl_bw *dl_b;
+ int cpu;
+ unsigned long flags;
+
+ def_dl_bandwidth.dl_period = global_rt_period();
+ def_dl_bandwidth.dl_runtime = global_rt_runtime();
+
+ if (global_rt_runtime() != RUNTIME_INF)
+ new_bw = to_ratio(global_rt_period(), global_rt_runtime());
+
+ /*
+ * FIXME: As above...
+ */
+ for_each_possible_cpu(cpu) {
+ rcu_read_lock_sched();
+ dl_b = dl_bw_of(cpu);
+
+ raw_spin_lock_irqsave(&dl_b->lock, flags);
+ dl_b->bw = new_bw;
+ raw_spin_unlock_irqrestore(&dl_b->lock, flags);
+
+ rcu_read_unlock_sched();
+ init_dl_rq_bw_ratio(&cpu_rq(cpu)->dl);
+ }
+}
+
+/*
+ * We must be sure that accepting a new task (or allowing changing the
+ * parameters of an existing one) is consistent with the bandwidth
+ * constraints. If yes, this function also accordingly updates the currently
+ * allocated bandwidth to reflect the new situation.
+ *
+ * This function is called while holding p's rq->lock.
+ */
+int sched_dl_overflow(struct task_struct *p, int policy,
+ const struct sched_attr *attr)
+{
+ struct dl_bw *dl_b = dl_bw_of(task_cpu(p));
+ u64 period = attr->sched_period ?: attr->sched_deadline;
+ u64 runtime = attr->sched_runtime;
+ u64 new_bw = dl_policy(policy) ? to_ratio(period, runtime) : 0;
+ int cpus, err = -1;
+
+ /* !deadline task may carry old deadline bandwidth */
+ if (new_bw == p->dl.dl_bw && task_has_dl_policy(p))
+ return 0;
+
+ /*
+ * Either if a task, enters, leave, or stays -deadline but changes
+ * its parameters, we may need to update accordingly the total
+ * allocated bandwidth of the container.
+ */
+ raw_spin_lock(&dl_b->lock);
+ cpus = dl_bw_cpus(task_cpu(p));
+ if (dl_policy(policy) && !task_has_dl_policy(p) &&
+ !__dl_overflow(dl_b, cpus, 0, new_bw)) {
+ if (hrtimer_active(&p->dl.inactive_timer))
+ __dl_clear(dl_b, p->dl.dl_bw, cpus);
+ __dl_add(dl_b, new_bw, cpus);
+ err = 0;
+ } else if (dl_policy(policy) && task_has_dl_policy(p) &&
+ !__dl_overflow(dl_b, cpus, p->dl.dl_bw, new_bw)) {
+ /*
+ * XXX this is slightly incorrect: when the task
+ * utilization decreases, we should delay the total
+ * utilization change until the task's 0-lag point.
+ * But this would require to set the task's "inactive
+ * timer" when the task is not inactive.
+ */
+ __dl_clear(dl_b, p->dl.dl_bw, cpus);
+ __dl_add(dl_b, new_bw, cpus);
+ dl_change_utilization(p, new_bw);
+ err = 0;
+ } else if (!dl_policy(policy) && task_has_dl_policy(p)) {
+ /*
+ * Do not decrease the total deadline utilization here,
+ * switched_from_dl() will take care to do it at the correct
+ * (0-lag) time.
+ */
+ err = 0;
+ }
+ raw_spin_unlock(&dl_b->lock);
+
+ return err;
+}
+
+/*
+ * This function initializes the sched_dl_entity of a newly becoming
+ * SCHED_DEADLINE task.
+ *
+ * Only the static values are considered here, the actual runtime and the
+ * absolute deadline will be properly calculated when the task is enqueued
+ * for the first time with its new policy.
+ */
+void __setparam_dl(struct task_struct *p, const struct sched_attr *attr)
+{
+ struct sched_dl_entity *dl_se = &p->dl;
+
+ dl_se->dl_runtime = attr->sched_runtime;
+ dl_se->dl_deadline = attr->sched_deadline;
+ dl_se->dl_period = attr->sched_period ?: dl_se->dl_deadline;
+ dl_se->flags = attr->sched_flags;
+ dl_se->dl_bw = to_ratio(dl_se->dl_period, dl_se->dl_runtime);
+ dl_se->dl_density = to_ratio(dl_se->dl_deadline, dl_se->dl_runtime);
+}
+
+void __getparam_dl(struct task_struct *p, struct sched_attr *attr)
+{
+ struct sched_dl_entity *dl_se = &p->dl;
+
+ attr->sched_priority = p->rt_priority;
+ attr->sched_runtime = dl_se->dl_runtime;
+ attr->sched_deadline = dl_se->dl_deadline;
+ attr->sched_period = dl_se->dl_period;
+ attr->sched_flags = dl_se->flags;
+}
+
+/*
+ * This function validates the new parameters of a -deadline task.
+ * We ask for the deadline not being zero, and greater or equal
+ * than the runtime, as well as the period of being zero or
+ * greater than deadline. Furthermore, we have to be sure that
+ * user parameters are above the internal resolution of 1us (we
+ * check sched_runtime only since it is always the smaller one) and
+ * below 2^63 ns (we have to check both sched_deadline and
+ * sched_period, as the latter can be zero).
+ */
+bool __checkparam_dl(const struct sched_attr *attr)
+{
+ /* deadline != 0 */
+ if (attr->sched_deadline == 0)
+ return false;
+
+ /*
+ * Since we truncate DL_SCALE bits, make sure we're at least
+ * that big.
+ */
+ if (attr->sched_runtime < (1ULL << DL_SCALE))
+ return false;
+
+ /*
+ * Since we use the MSB for wrap-around and sign issues, make
+ * sure it's not set (mind that period can be equal to zero).
+ */
+ if (attr->sched_deadline & (1ULL << 63) ||
+ attr->sched_period & (1ULL << 63))
+ return false;
+
+ /* runtime <= deadline <= period (if period != 0) */
+ if ((attr->sched_period != 0 &&
+ attr->sched_period < attr->sched_deadline) ||
+ attr->sched_deadline < attr->sched_runtime)
+ return false;
+
+ return true;
+}
+
+/*
+ * This function clears the sched_dl_entity static params.
+ */
+void __dl_clear_params(struct task_struct *p)
+{
+ struct sched_dl_entity *dl_se = &p->dl;
+
+ dl_se->dl_runtime = 0;
+ dl_se->dl_deadline = 0;
+ dl_se->dl_period = 0;
+ dl_se->flags = 0;
+ dl_se->dl_bw = 0;
+ dl_se->dl_density = 0;
+
+ dl_se->dl_throttled = 0;
+ dl_se->dl_yielded = 0;
+ dl_se->dl_non_contending = 0;
+}
+
+bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr)
+{
+ struct sched_dl_entity *dl_se = &p->dl;
+
+ if (dl_se->dl_runtime != attr->sched_runtime ||
+ dl_se->dl_deadline != attr->sched_deadline ||
+ dl_se->dl_period != attr->sched_period ||
+ dl_se->flags != attr->sched_flags)
+ return true;
+
+ return false;
+}
+
+#ifdef CONFIG_SMP
+int dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed)
+{
+ unsigned int dest_cpu = cpumask_any_and(cpu_active_mask,
+ cs_cpus_allowed);
+ struct dl_bw *dl_b;
+ bool overflow;
+ int cpus, ret;
+ unsigned long flags;
+
+ rcu_read_lock_sched();
+ dl_b = dl_bw_of(dest_cpu);
+ raw_spin_lock_irqsave(&dl_b->lock, flags);
+ cpus = dl_bw_cpus(dest_cpu);
+ overflow = __dl_overflow(dl_b, cpus, 0, p->dl.dl_bw);
+ if (overflow)
+ ret = -EBUSY;
+ else {
+ /*
+ * We reserve space for this task in the destination
+ * root_domain, as we can't fail after this point.
+ * We will free resources in the source root_domain
+ * later on (see set_cpus_allowed_dl()).
+ */
+ __dl_add(dl_b, p->dl.dl_bw, cpus);
+ ret = 0;
+ }
+ raw_spin_unlock_irqrestore(&dl_b->lock, flags);
+ rcu_read_unlock_sched();
+ return ret;
+}
+
+int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur,
+ const struct cpumask *trial)
+{
+ int ret = 1, trial_cpus;
+ struct dl_bw *cur_dl_b;
+ unsigned long flags;
+
+ rcu_read_lock_sched();
+ cur_dl_b = dl_bw_of(cpumask_any(cur));
+ trial_cpus = cpumask_weight(trial);
+
+ raw_spin_lock_irqsave(&cur_dl_b->lock, flags);
+ if (cur_dl_b->bw != -1 &&
+ cur_dl_b->bw * trial_cpus < cur_dl_b->total_bw)
+ ret = 0;
+ raw_spin_unlock_irqrestore(&cur_dl_b->lock, flags);
+ rcu_read_unlock_sched();
+ return ret;
+}
+
+bool dl_cpu_busy(unsigned int cpu)
+{
+ unsigned long flags;
+ struct dl_bw *dl_b;
+ 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();
+ return overflow;
+}
+#endif
+
#ifdef CONFIG_SCHED_DEBUG
extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);

diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index e0329d10bd..d4eb3f6752 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -218,9 +218,6 @@ static inline int dl_bandwidth_enabled(void)
return sysctl_sched_rt_runtime >= 0;
}

-extern struct dl_bw *dl_bw_of(int i);
-extern int dl_bw_cpus(int i);
-
struct dl_bw {
raw_spinlock_t lock;
u64 bw, total_bw;
@@ -251,6 +248,20 @@ bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)

void dl_change_utilization(struct task_struct *p, u64 new_bw);
extern void init_dl_bw(struct dl_bw *dl_b);
+extern int sched_dl_global_validate(void);
+extern void sched_dl_do_global(void);
+extern int sched_dl_overflow(struct task_struct *p, int policy,
+ const struct sched_attr *attr);
+extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
+extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
+extern bool __checkparam_dl(const struct sched_attr *attr);
+extern void __dl_clear_params(struct task_struct *p);
+extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
+extern int dl_task_can_attach(struct task_struct *p,
+ const struct cpumask *cs_cpus_allowed);
+extern int dl_cpuset_cpumask_can_shrink(const struct cpumask *cur,
+ const struct cpumask *trial);
+extern bool dl_cpu_busy(unsigned int cpu);

#ifdef CONFIG_CGROUP_SCHED

--
2.9.4