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-rw-r--r--kernel/sched/core.c2376
1 files changed, 1456 insertions, 920 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 5ac63c9a995..bc1638b3344 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -73,6 +73,7 @@
#include <linux/init_task.h>
#include <linux/binfmts.h>
#include <linux/context_tracking.h>
+#include <linux/compiler.h>
#include <asm/switch_to.h>
#include <asm/tlb.h>
@@ -89,6 +90,22 @@
#define CREATE_TRACE_POINTS
#include <trace/events/sched.h>
+#ifdef smp_mb__before_atomic
+void __smp_mb__before_atomic(void)
+{
+ smp_mb__before_atomic();
+}
+EXPORT_SYMBOL(__smp_mb__before_atomic);
+#endif
+
+#ifdef smp_mb__after_atomic
+void __smp_mb__after_atomic(void)
+{
+ smp_mb__after_atomic();
+}
+EXPORT_SYMBOL(__smp_mb__after_atomic);
+#endif
+
void start_bandwidth_timer(struct hrtimer *period_timer, ktime_t period)
{
unsigned long delta;
@@ -296,8 +313,6 @@ __read_mostly int scheduler_running;
*/
int sysctl_sched_rt_runtime = 950000;
-
-
/*
* __task_rq_lock - lock the rq @p resides on.
*/
@@ -434,7 +449,7 @@ void hrtick_start(struct rq *rq, u64 delay)
if (rq == this_rq()) {
__hrtick_restart(rq);
} else if (!rq->hrtick_csd_pending) {
- __smp_call_function_single(cpu_of(rq), &rq->hrtick_csd, 0);
+ smp_call_function_single_async(cpu_of(rq), &rq->hrtick_csd);
rq->hrtick_csd_pending = 1;
}
}
@@ -507,32 +522,98 @@ static inline void init_hrtick(void)
#endif /* CONFIG_SCHED_HRTICK */
/*
+ * cmpxchg based fetch_or, macro so it works for different integer types
+ */
+#define fetch_or(ptr, val) \
+({ typeof(*(ptr)) __old, __val = *(ptr); \
+ for (;;) { \
+ __old = cmpxchg((ptr), __val, __val | (val)); \
+ if (__old == __val) \
+ break; \
+ __val = __old; \
+ } \
+ __old; \
+})
+
+#if defined(CONFIG_SMP) && defined(TIF_POLLING_NRFLAG)
+/*
+ * Atomically set TIF_NEED_RESCHED and test for TIF_POLLING_NRFLAG,
+ * this avoids any races wrt polling state changes and thereby avoids
+ * spurious IPIs.
+ */
+static bool set_nr_and_not_polling(struct task_struct *p)
+{
+ struct thread_info *ti = task_thread_info(p);
+ return !(fetch_or(&ti->flags, _TIF_NEED_RESCHED) & _TIF_POLLING_NRFLAG);
+}
+
+/*
+ * Atomically set TIF_NEED_RESCHED if TIF_POLLING_NRFLAG is set.
+ *
+ * If this returns true, then the idle task promises to call
+ * sched_ttwu_pending() and reschedule soon.
+ */
+static bool set_nr_if_polling(struct task_struct *p)
+{
+ struct thread_info *ti = task_thread_info(p);
+ typeof(ti->flags) old, val = ACCESS_ONCE(ti->flags);
+
+ for (;;) {
+ if (!(val & _TIF_POLLING_NRFLAG))
+ return false;
+ if (val & _TIF_NEED_RESCHED)
+ return true;
+ old = cmpxchg(&ti->flags, val, val | _TIF_NEED_RESCHED);
+ if (old == val)
+ break;
+ val = old;
+ }
+ return true;
+}
+
+#else
+static bool set_nr_and_not_polling(struct task_struct *p)
+{
+ set_tsk_need_resched(p);
+ return true;
+}
+
+#ifdef CONFIG_SMP
+static bool set_nr_if_polling(struct task_struct *p)
+{
+ return false;
+}
+#endif
+#endif
+
+/*
* resched_task - mark a task 'to be rescheduled now'.
*
* On UP this means the setting of the need_resched flag, on SMP it
* might also involve a cross-CPU call to trigger the scheduler on
* the target CPU.
*/
-#ifdef CONFIG_SMP
void resched_task(struct task_struct *p)
{
int cpu;
- assert_raw_spin_locked(&task_rq(p)->lock);
+ lockdep_assert_held(&task_rq(p)->lock);
if (test_tsk_need_resched(p))
return;
- set_tsk_need_resched(p);
-
cpu = task_cpu(p);
- if (cpu == smp_processor_id())
+
+ if (cpu == smp_processor_id()) {
+ set_tsk_need_resched(p);
+ set_preempt_need_resched();
return;
+ }
- /* NEED_RESCHED must be visible before we test polling */
- smp_mb();
- if (!tsk_is_polling(p))
+ if (set_nr_and_not_polling(p))
smp_send_reschedule(cpu);
+ else
+ trace_sched_wake_idle_without_ipi(cpu);
}
void resched_cpu(int cpu)
@@ -546,6 +627,7 @@ void resched_cpu(int cpu)
raw_spin_unlock_irqrestore(&rq->lock, flags);
}
+#ifdef CONFIG_SMP
#ifdef CONFIG_NO_HZ_COMMON
/*
* In the semi idle case, use the nearest busy cpu for migrating timers
@@ -555,12 +637,15 @@ void resched_cpu(int cpu)
* selecting an idle cpu will add more delays to the timers than intended
* (as that cpu's timer base may not be uptodate wrt jiffies etc).
*/
-int get_nohz_timer_target(void)
+int get_nohz_timer_target(int pinned)
{
int cpu = smp_processor_id();
int i;
struct sched_domain *sd;
+ if (pinned || !get_sysctl_timer_migration() || !idle_cpu(cpu))
+ return cpu;
+
rcu_read_lock();
for_each_domain(cpu, sd) {
for_each_cpu(i, sched_domain_span(sd)) {
@@ -591,27 +676,10 @@ static void wake_up_idle_cpu(int cpu)
if (cpu == smp_processor_id())
return;
- /*
- * This is safe, as this function is called with the timer
- * wheel base lock of (cpu) held. When the CPU is on the way
- * to idle and has not yet set rq->curr to idle then it will
- * be serialized on the timer wheel base lock and take the new
- * timer into account automatically.
- */
- if (rq->curr != rq->idle)
- return;
-
- /*
- * We can set TIF_RESCHED on the idle task of the other CPU
- * lockless. The worst case is that the other CPU runs the
- * idle task through an additional NOOP schedule()
- */
- set_tsk_need_resched(rq->idle);
-
- /* NEED_RESCHED must be visible before we test polling */
- smp_mb();
- if (!tsk_is_polling(rq->idle))
+ if (set_nr_and_not_polling(rq->idle))
smp_send_reschedule(cpu);
+ else
+ trace_sched_wake_idle_without_ipi(cpu);
}
static bool wake_up_full_nohz_cpu(int cpu)
@@ -693,12 +761,6 @@ void sched_avg_update(struct rq *rq)
}
}
-#else /* !CONFIG_SMP */
-void resched_task(struct task_struct *p)
-{
- assert_raw_spin_locked(&task_rq(p)->lock);
- set_tsk_need_resched(p);
-}
#endif /* CONFIG_SMP */
#if defined(CONFIG_RT_GROUP_SCHED) || (defined(CONFIG_FAIR_GROUP_SCHED) && \
@@ -767,14 +829,14 @@ static void set_load_weight(struct task_struct *p)
static void enqueue_task(struct rq *rq, struct task_struct *p, int flags)
{
update_rq_clock(rq);
- sched_info_queued(p);
+ sched_info_queued(rq, p);
p->sched_class->enqueue_task(rq, p, flags);
}
static void dequeue_task(struct rq *rq, struct task_struct *p, int flags)
{
update_rq_clock(rq);
- sched_info_dequeued(p);
+ sched_info_dequeued(rq, p);
p->sched_class->dequeue_task(rq, p, flags);
}
@@ -829,19 +891,13 @@ static void update_rq_clock_task(struct rq *rq, s64 delta)
#endif
#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
if (static_key_false((&paravirt_steal_rq_enabled))) {
- u64 st;
-
steal = paravirt_steal_clock(cpu_of(rq));
steal -= rq->prev_steal_time_rq;
if (unlikely(steal > delta))
steal = delta;
- st = steal_ticks(steal);
- steal = st * TICK_NSEC;
-
rq->prev_steal_time_rq += steal;
-
delta -= steal;
}
#endif
@@ -849,7 +905,7 @@ static void update_rq_clock_task(struct rq *rq, s64 delta)
rq->clock_task += delta;
#if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
- if ((irq_delta + steal) && sched_feat(NONTASK_POWER))
+ if ((irq_delta + steal) && sched_feat(NONTASK_CAPACITY))
sched_rt_avg_update(rq, irq_delta + steal);
#endif
}
@@ -903,7 +959,9 @@ static inline int normal_prio(struct task_struct *p)
{
int prio;
- if (task_has_rt_policy(p))
+ if (task_has_dl_policy(p))
+ prio = MAX_DL_PRIO-1;
+ else if (task_has_rt_policy(p))
prio = MAX_RT_PRIO-1 - p->rt_priority;
else
prio = __normal_prio(p);
@@ -949,7 +1007,7 @@ static inline void check_class_changed(struct rq *rq, struct task_struct *p,
if (prev_class->switched_from)
prev_class->switched_from(rq, p);
p->sched_class->switched_to(rq, p);
- } else if (oldprio != p->prio)
+ } else if (oldprio != p->prio || dl_task(p))
p->sched_class->prio_changed(rq, p, oldprio);
}
@@ -987,7 +1045,7 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
* ttwu() will sort out the placement.
*/
WARN_ON_ONCE(p->state != TASK_RUNNING && p->state != TASK_WAKING &&
- !(task_thread_info(p)->preempt_count & PREEMPT_ACTIVE));
+ !(task_preempt_count(p) & PREEMPT_ACTIVE));
#ifdef CONFIG_LOCKDEP
/*
@@ -1017,6 +1075,108 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu)
__set_task_cpu(p, new_cpu);
}
+static void __migrate_swap_task(struct task_struct *p, int cpu)
+{
+ if (p->on_rq) {
+ struct rq *src_rq, *dst_rq;
+
+ src_rq = task_rq(p);
+ dst_rq = cpu_rq(cpu);
+
+ deactivate_task(src_rq, p, 0);
+ set_task_cpu(p, cpu);
+ activate_task(dst_rq, p, 0);
+ check_preempt_curr(dst_rq, p, 0);
+ } else {
+ /*
+ * Task isn't running anymore; make it appear like we migrated
+ * it before it went to sleep. This means on wakeup we make the
+ * previous cpu our targer instead of where it really is.
+ */
+ p->wake_cpu = cpu;
+ }
+}
+
+struct migration_swap_arg {
+ struct task_struct *src_task, *dst_task;
+ int src_cpu, dst_cpu;
+};
+
+static int migrate_swap_stop(void *data)
+{
+ struct migration_swap_arg *arg = data;
+ struct rq *src_rq, *dst_rq;
+ int ret = -EAGAIN;
+
+ src_rq = cpu_rq(arg->src_cpu);
+ dst_rq = cpu_rq(arg->dst_cpu);
+
+ double_raw_lock(&arg->src_task->pi_lock,
+ &arg->dst_task->pi_lock);
+ double_rq_lock(src_rq, dst_rq);
+ if (task_cpu(arg->dst_task) != arg->dst_cpu)
+ goto unlock;
+
+ if (task_cpu(arg->src_task) != arg->src_cpu)
+ goto unlock;
+
+ if (!cpumask_test_cpu(arg->dst_cpu, tsk_cpus_allowed(arg->src_task)))
+ goto unlock;
+
+ if (!cpumask_test_cpu(arg->src_cpu, tsk_cpus_allowed(arg->dst_task)))
+ goto unlock;
+
+ __migrate_swap_task(arg->src_task, arg->dst_cpu);
+ __migrate_swap_task(arg->dst_task, arg->src_cpu);
+
+ ret = 0;
+
+unlock:
+ double_rq_unlock(src_rq, dst_rq);
+ raw_spin_unlock(&arg->dst_task->pi_lock);
+ raw_spin_unlock(&arg->src_task->pi_lock);
+
+ return ret;
+}
+
+/*
+ * Cross migrate two tasks
+ */
+int migrate_swap(struct task_struct *cur, struct task_struct *p)
+{
+ struct migration_swap_arg arg;
+ int ret = -EINVAL;
+
+ arg = (struct migration_swap_arg){
+ .src_task = cur,
+ .src_cpu = task_cpu(cur),
+ .dst_task = p,
+ .dst_cpu = task_cpu(p),
+ };
+
+ if (arg.src_cpu == arg.dst_cpu)
+ goto out;
+
+ /*
+ * These three tests are all lockless; this is OK since all of them
+ * will be re-checked with proper locks held further down the line.
+ */
+ if (!cpu_active(arg.src_cpu) || !cpu_active(arg.dst_cpu))
+ goto out;
+
+ if (!cpumask_test_cpu(arg.dst_cpu, tsk_cpus_allowed(arg.src_task)))
+ goto out;
+
+ if (!cpumask_test_cpu(arg.src_cpu, tsk_cpus_allowed(arg.dst_task)))
+ goto out;
+
+ trace_sched_swap_numa(cur, arg.src_cpu, p, arg.dst_cpu);
+ ret = stop_two_cpus(arg.dst_cpu, arg.src_cpu, migrate_swap_stop, &arg);
+
+out:
+ return ret;
+}
+
struct migration_arg {
struct task_struct *task;
int dest_cpu;
@@ -1224,7 +1384,7 @@ out:
* leave kernel.
*/
if (p->mm && printk_ratelimit()) {
- printk_sched("process %d (%s) no longer affine to cpu%d\n",
+ printk_deferred("process %d (%s) no longer affine to cpu%d\n",
task_pid_nr(p), p->comm, cpu);
}
}
@@ -1236,9 +1396,9 @@ out:
* The caller (fork, wakeup) owns p->pi_lock, ->cpus_allowed is stable.
*/
static inline
-int select_task_rq(struct task_struct *p, int sd_flags, int wake_flags)
+int select_task_rq(struct task_struct *p, int cpu, int sd_flags, int wake_flags)
{
- int cpu = p->sched_class->select_task_rq(p, sd_flags, wake_flags);
+ cpu = p->sched_class->select_task_rq(p, cpu, sd_flags, wake_flags);
/*
* In order not to call set_task_cpu() on a blocking task we need
@@ -1330,12 +1490,13 @@ ttwu_do_wakeup(struct rq *rq, struct task_struct *p, int wake_flags)
if (rq->idle_stamp) {
u64 delta = rq_clock(rq) - rq->idle_stamp;
- u64 max = 2*sysctl_sched_migration_cost;
+ u64 max = 2*rq->max_idle_balance_cost;
+
+ update_avg(&rq->avg_idle, delta);
- if (delta > max)
+ if (rq->avg_idle > max)
rq->avg_idle = max;
- else
- update_avg(&rq->avg_idle, delta);
+
rq->idle_stamp = 0;
}
#endif
@@ -1377,13 +1538,17 @@ static int ttwu_remote(struct task_struct *p, int wake_flags)
}
#ifdef CONFIG_SMP
-static void sched_ttwu_pending(void)
+void sched_ttwu_pending(void)
{
struct rq *rq = this_rq();
struct llist_node *llist = llist_del_all(&rq->wake_list);
struct task_struct *p;
+ unsigned long flags;
- raw_spin_lock(&rq->lock);
+ if (!llist)
+ return;
+
+ raw_spin_lock_irqsave(&rq->lock, flags);
while (llist) {
p = llist_entry(llist, struct task_struct, wake_entry);
@@ -1391,11 +1556,18 @@ static void sched_ttwu_pending(void)
ttwu_do_activate(rq, p, 0);
}
- raw_spin_unlock(&rq->lock);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
}
void scheduler_ipi(void)
{
+ /*
+ * Fold TIF_NEED_RESCHED into the preempt_count; anybody setting
+ * TIF_NEED_RESCHED remotely (for the first time) will also send
+ * this IPI.
+ */
+ preempt_fold_need_resched();
+
if (llist_empty(&this_rq()->wake_list)
&& !tick_nohz_full_cpu(smp_processor_id())
&& !got_nohz_idle_kick())
@@ -1430,8 +1602,14 @@ void scheduler_ipi(void)
static void ttwu_queue_remote(struct task_struct *p, int cpu)
{
- if (llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list))
- smp_send_reschedule(cpu);
+ struct rq *rq = cpu_rq(cpu);
+
+ if (llist_add(&p->wake_entry, &cpu_rq(cpu)->wake_list)) {
+ if (!set_nr_if_polling(rq->idle))
+ smp_send_reschedule(cpu);
+ else
+ trace_sched_wake_idle_without_ipi(cpu);
+ }
}
bool cpus_share_cache(int this_cpu, int that_cpu)
@@ -1513,7 +1691,7 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
if (p->sched_class->task_waking)
p->sched_class->task_waking(p);
- cpu = select_task_rq(p, SD_BALANCE_WAKE, wake_flags);
+ cpu = select_task_rq(p, p->wake_cpu, SD_BALANCE_WAKE, wake_flags);
if (task_cpu(p) != cpu) {
wake_flags |= WF_MIGRATED;
set_task_cpu(p, cpu);
@@ -1595,7 +1773,7 @@ int wake_up_state(struct task_struct *p, unsigned int state)
*
* __sched_fork() is basic setup used by init_idle() too:
*/
-static void __sched_fork(struct task_struct *p)
+static void __sched_fork(unsigned long clone_flags, struct task_struct *p)
{
p->on_rq = 0;
@@ -1611,6 +1789,13 @@ static void __sched_fork(struct task_struct *p)
memset(&p->se.statistics, 0, sizeof(p->se.statistics));
#endif
+ RB_CLEAR_NODE(&p->dl.rb_node);
+ hrtimer_init(&p->dl.dl_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ p->dl.dl_runtime = p->dl.runtime = 0;
+ p->dl.dl_deadline = p->dl.deadline = 0;
+ p->dl.dl_period = 0;
+ p->dl.flags = 0;
+
INIT_LIST_HEAD(&p->rt.run_list);
#ifdef CONFIG_PREEMPT_NOTIFIERS
@@ -1619,16 +1804,26 @@ static void __sched_fork(struct task_struct *p)
#ifdef CONFIG_NUMA_BALANCING
if (p->mm && atomic_read(&p->mm->mm_users) == 1) {
- p->mm->numa_next_scan = jiffies;
- p->mm->numa_next_reset = jiffies;
+ p->mm->numa_next_scan = jiffies + msecs_to_jiffies(sysctl_numa_balancing_scan_delay);
p->mm->numa_scan_seq = 0;
}
+ if (clone_flags & CLONE_VM)
+ p->numa_preferred_nid = current->numa_preferred_nid;
+ else
+ p->numa_preferred_nid = -1;
+
p->node_stamp = 0ULL;
p->numa_scan_seq = p->mm ? p->mm->numa_scan_seq : 0;
- p->numa_migrate_seq = p->mm ? p->mm->numa_scan_seq - 1 : 0;
p->numa_scan_period = sysctl_numa_balancing_scan_delay;
p->numa_work.next = &p->numa_work;
+ p->numa_faults_memory = NULL;
+ p->numa_faults_buffer_memory = NULL;
+ p->last_task_numa_placement = 0;
+ p->last_sum_exec_runtime = 0;
+
+ INIT_LIST_HEAD(&p->numa_entry);
+ p->numa_group = NULL;
#endif /* CONFIG_NUMA_BALANCING */
}
@@ -1649,17 +1844,39 @@ void set_numabalancing_state(bool enabled)
numabalancing_enabled = enabled;
}
#endif /* CONFIG_SCHED_DEBUG */
-#endif /* CONFIG_NUMA_BALANCING */
+
+#ifdef CONFIG_PROC_SYSCTL
+int sysctl_numa_balancing(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table t;
+ int err;
+ int state = numabalancing_enabled;
+
+ if (write && !capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ t = *table;
+ t.data = &state;
+ err = proc_dointvec_minmax(&t, write, buffer, lenp, ppos);
+ if (err < 0)
+ return err;
+ if (write)
+ set_numabalancing_state(state);
+ return err;
+}
+#endif
+#endif
/*
* fork()/clone()-time setup:
*/
-void sched_fork(struct task_struct *p)
+int sched_fork(unsigned long clone_flags, struct task_struct *p)
{
unsigned long flags;
int cpu = get_cpu();
- __sched_fork(p);
+ __sched_fork(clone_flags, p);
/*
* We mark the process as running here. This guarantees that
* nobody will actually run it, and a signal or other external
@@ -1676,7 +1893,7 @@ void sched_fork(struct task_struct *p)
* Revert to default priority/policy on fork if requested.
*/
if (unlikely(p->sched_reset_on_fork)) {
- if (task_has_rt_policy(p)) {
+ if (task_has_dl_policy(p) || task_has_rt_policy(p)) {
p->policy = SCHED_NORMAL;
p->static_prio = NICE_TO_PRIO(0);
p->rt_priority = 0;
@@ -1693,8 +1910,14 @@ void sched_fork(struct task_struct *p)
p->sched_reset_on_fork = 0;
}
- if (!rt_prio(p->prio))
+ if (dl_prio(p->prio)) {
+ put_cpu();
+ return -EAGAIN;
+ } else if (rt_prio(p->prio)) {
+ p->sched_class = &rt_sched_class;
+ } else {
p->sched_class = &fair_sched_class;
+ }
if (p->sched_class->task_fork)
p->sched_class->task_fork(p);
@@ -1717,17 +1940,127 @@ void sched_fork(struct task_struct *p)
#if defined(CONFIG_SMP)
p->on_cpu = 0;
#endif
-#ifdef CONFIG_PREEMPT_COUNT
- /* Want to start with kernel preemption disabled. */
- task_thread_info(p)->preempt_count = 1;
-#endif
+ init_task_preempt_count(p);
#ifdef CONFIG_SMP
plist_node_init(&p->pushable_tasks, MAX_PRIO);
+ RB_CLEAR_NODE(&p->pushable_dl_tasks);
#endif
put_cpu();
+ return 0;
+}
+
+unsigned long to_ratio(u64 period, u64 runtime)
+{
+ if (runtime == RUNTIME_INF)
+ return 1ULL << 20;
+
+ /*
+ * Doing this here saves a lot of checks in all
+ * the calling paths, and returning zero seems
+ * safe for them anyway.
+ */
+ if (period == 0)
+ return 0;
+
+ return div64_u64(runtime << 20, period);
+}
+
+#ifdef CONFIG_SMP
+inline struct dl_bw *dl_bw_of(int i)
+{
+ 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;
+
+ 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;
+}
+
+static inline int dl_bw_cpus(int i)
+{
+ return 1;
+}
+#endif
+
+static inline
+void __dl_clear(struct dl_bw *dl_b, u64 tsk_bw)
+{
+ dl_b->total_bw -= tsk_bw;
+}
+
+static inline
+void __dl_add(struct dl_bw *dl_b, u64 tsk_bw)
+{
+ dl_b->total_bw += tsk_bw;
+}
+
+static inline
+bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)
+{
+ return dl_b->bw != -1 &&
+ dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw;
+}
+
+/*
+ * 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;
+
+ if (new_bw == p->dl.dl_bw)
+ 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)) {
+ __dl_add(dl_b, new_bw);
+ err = 0;
+ } else if (dl_policy(policy) && task_has_dl_policy(p) &&
+ !__dl_overflow(dl_b, cpus, p->dl.dl_bw, new_bw)) {
+ __dl_clear(dl_b, p->dl.dl_bw);
+ __dl_add(dl_b, new_bw);
+ err = 0;
+ } else if (!dl_policy(policy) && task_has_dl_policy(p)) {
+ __dl_clear(dl_b, p->dl.dl_bw);
+ 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.
*
@@ -1747,7 +2080,7 @@ void wake_up_new_task(struct task_struct *p)
* - cpus_allowed can change in the fork path
* - any previously selected cpu might disappear through hotplug
*/
- set_task_cpu(p, select_task_rq(p, SD_BALANCE_FORK, 0));
+ set_task_cpu(p, select_task_rq(p, task_cpu(p), SD_BALANCE_FORK, 0));
#endif
/* Initialize new task's runnable average */
@@ -1838,7 +2171,7 @@ prepare_task_switch(struct rq *rq, struct task_struct *prev,
struct task_struct *next)
{
trace_sched_switch(prev, next);
- sched_info_switch(prev, next);
+ sched_info_switch(rq, prev, next);
perf_event_task_sched_out(prev, next);
fire_sched_out_preempt_notifiers(prev, next);
prepare_lock_switch(rq, next);
@@ -1890,6 +2223,9 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev)
if (mm)
mmdrop(mm);
if (unlikely(prev_state == TASK_DEAD)) {
+ if (prev->sched_class->task_dead)
+ prev->sched_class->task_dead(prev);
+
/*
* Remove function-return probe instances associated with this
* task and put them back on the free list.
@@ -1903,13 +2239,6 @@ static void finish_task_switch(struct rq *rq, struct task_struct *prev)
#ifdef CONFIG_SMP
-/* assumes rq->lock is held */
-static inline void pre_schedule(struct rq *rq, struct task_struct *prev)
-{
- if (prev->sched_class->pre_schedule)
- prev->sched_class->pre_schedule(rq, prev);
-}
-
/* rq->lock is NOT held, but preemption is disabled */
static inline void post_schedule(struct rq *rq)
{
@@ -1927,10 +2256,6 @@ static inline void post_schedule(struct rq *rq)
#else
-static inline void pre_schedule(struct rq *rq, struct task_struct *p)
-{
-}
-
static inline void post_schedule(struct rq *rq)
{
}
@@ -1941,7 +2266,7 @@ static inline void post_schedule(struct rq *rq)
* schedule_tail - first thing a freshly forked thread must call.
* @prev: the thread we just switched away from.
*/
-asmlinkage void schedule_tail(struct task_struct *prev)
+asmlinkage __visible void schedule_tail(struct task_struct *prev)
__releases(rq->lock)
{
struct rq *rq = this_rq();
@@ -2073,7 +2398,7 @@ void sched_exec(void)
int dest_cpu;
raw_spin_lock_irqsave(&p->pi_lock, flags);
- dest_cpu = p->sched_class->select_task_rq(p, SD_BALANCE_EXEC, 0);
+ dest_cpu = p->sched_class->select_task_rq(p, task_cpu(p), SD_BALANCE_EXEC, 0);
if (dest_cpu == smp_processor_id())
goto unlock;
@@ -2140,6 +2465,20 @@ unsigned long long task_sched_runtime(struct task_struct *p)
struct rq *rq;
u64 ns = 0;
+#if defined(CONFIG_64BIT) && defined(CONFIG_SMP)
+ /*
+ * 64-bit doesn't need locks to atomically read a 64bit value.
+ * So we have a optimization chance when the task's delta_exec is 0.
+ * Reading ->on_cpu is racy, but this is ok.
+ *
+ * If we race with it leaving cpu, we'll take a lock. So we're correct.
+ * If we race with it entering cpu, unaccounted time is 0. This is
+ * indistinguishable from the read occurring a few cycles earlier.
+ */
+ if (!p->on_cpu)
+ return p->se.sum_exec_runtime;
+#endif
+
rq = task_rq_lock(p, &flags);
ns = p->se.sum_exec_runtime + do_task_delta_exec(p, rq);
task_rq_unlock(rq, p, &flags);
@@ -2169,7 +2508,7 @@ void scheduler_tick(void)
#ifdef CONFIG_SMP
rq->idle_balance = idle_cpu(cpu);
- trigger_load_balance(rq, cpu);
+ trigger_load_balance(rq);
#endif
rq_last_tick_reset(rq);
}
@@ -2198,7 +2537,7 @@ u64 scheduler_tick_max_deferment(void)
if (time_before_eq(next, now))
return 0;
- return jiffies_to_usecs(next - now) * NSEC_PER_USEC;
+ return jiffies_to_nsecs(next - now);
}
#endif
@@ -2215,7 +2554,7 @@ notrace unsigned long get_parent_ip(unsigned long addr)
#if defined(CONFIG_PREEMPT) && (defined(CONFIG_DEBUG_PREEMPT) || \
defined(CONFIG_PREEMPT_TRACER))
-void __kprobes add_preempt_count(int val)
+void preempt_count_add(int val)
{
#ifdef CONFIG_DEBUG_PREEMPT
/*
@@ -2224,7 +2563,7 @@ void __kprobes add_preempt_count(int val)
if (DEBUG_LOCKS_WARN_ON((preempt_count() < 0)))
return;
#endif
- preempt_count() += val;
+ __preempt_count_add(val);
#ifdef CONFIG_DEBUG_PREEMPT
/*
* Spinlock count overflowing soon?
@@ -2232,12 +2571,18 @@ void __kprobes add_preempt_count(int val)
DEBUG_LOCKS_WARN_ON((preempt_count() & PREEMPT_MASK) >=
PREEMPT_MASK - 10);
#endif
- if (preempt_count() == val)
- trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
+ if (preempt_count() == val) {
+ unsigned long ip = get_parent_ip(CALLER_ADDR1);
+#ifdef CONFIG_DEBUG_PREEMPT
+ current->preempt_disable_ip = ip;
+#endif
+ trace_preempt_off(CALLER_ADDR0, ip);
+ }
}
-EXPORT_SYMBOL(add_preempt_count);
+EXPORT_SYMBOL(preempt_count_add);
+NOKPROBE_SYMBOL(preempt_count_add);
-void __kprobes sub_preempt_count(int val)
+void preempt_count_sub(int val)
{
#ifdef CONFIG_DEBUG_PREEMPT
/*
@@ -2255,9 +2600,10 @@ void __kprobes sub_preempt_count(int val)
if (preempt_count() == val)
trace_preempt_on(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
- preempt_count() -= val;
+ __preempt_count_sub(val);
}
-EXPORT_SYMBOL(sub_preempt_count);
+EXPORT_SYMBOL(preempt_count_sub);
+NOKPROBE_SYMBOL(preempt_count_sub);
#endif
@@ -2276,6 +2622,13 @@ static noinline void __schedule_bug(struct task_struct *prev)
print_modules();
if (irqs_disabled())
print_irqtrace_events(prev);
+#ifdef CONFIG_DEBUG_PREEMPT
+ if (in_atomic_preempt_off()) {
+ pr_err("Preemption disabled at:");
+ print_ip_sym(current->preempt_disable_ip);
+ pr_cont("\n");
+ }
+#endif
dump_stack();
add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
}
@@ -2287,10 +2640,10 @@ static inline void schedule_debug(struct task_struct *prev)
{
/*
* Test if we are atomic. Since do_exit() needs to call into
- * schedule() atomically, we ignore that path for now.
- * Otherwise, whine if we are scheduling when we should not be.
+ * schedule() atomically, we ignore that path. Otherwise whine
+ * if we are scheduling when we should not.
*/
- if (unlikely(in_atomic_preempt_off() && !prev->exit_state))
+ if (unlikely(in_atomic_preempt_off() && prev->state != TASK_DEAD))
__schedule_bug(prev);
rcu_sleep_check();
@@ -2299,36 +2652,40 @@ static inline void schedule_debug(struct task_struct *prev)
schedstat_inc(this_rq(), sched_count);
}
-static void put_prev_task(struct rq *rq, struct task_struct *prev)
-{
- if (prev->on_rq || rq->skip_clock_update < 0)
- update_rq_clock(rq);
- prev->sched_class->put_prev_task(rq, prev);
-}
-
/*
* Pick up the highest-prio task:
*/
static inline struct task_struct *
-pick_next_task(struct rq *rq)
+pick_next_task(struct rq *rq, struct task_struct *prev)
{
- const struct sched_class *class;
+ const struct sched_class *class = &fair_sched_class;
struct task_struct *p;
/*
* Optimization: we know that if all tasks are in
* the fair class we can call that function directly:
*/
- if (likely(rq->nr_running == rq->cfs.h_nr_running)) {
- p = fair_sched_class.pick_next_task(rq);
- if (likely(p))
- return p;
+ if (likely(prev->sched_class == class &&
+ rq->nr_running == rq->cfs.h_nr_running)) {
+ p = fair_sched_class.pick_next_task(rq, prev);
+ if (unlikely(p == RETRY_TASK))
+ goto again;
+
+ /* assumes fair_sched_class->next == idle_sched_class */
+ if (unlikely(!p))
+ p = idle_sched_class.pick_next_task(rq, prev);
+
+ return p;
}
+again:
for_each_class(class) {
- p = class->pick_next_task(rq);
- if (p)
+ p = class->pick_next_task(rq, prev);
+ if (p) {
+ if (unlikely(p == RETRY_TASK))
+ goto again;
return p;
+ }
}
BUG(); /* the idle class will always have a runnable task */
@@ -2422,14 +2779,12 @@ need_resched:
switch_count = &prev->nvcsw;
}
- pre_schedule(rq, prev);
-
- if (unlikely(!rq->nr_running))
- idle_balance(cpu, rq);
+ if (prev->on_rq || rq->skip_clock_update < 0)
+ update_rq_clock(rq);
- put_prev_task(rq, prev);
- next = pick_next_task(rq);
+ next = pick_next_task(rq, prev);
clear_tsk_need_resched(prev);
+ clear_preempt_need_resched();
rq->skip_clock_update = 0;
if (likely(prev != next)) {
@@ -2468,7 +2823,7 @@ static inline void sched_submit_work(struct task_struct *tsk)
blk_schedule_flush_plug(tsk);
}
-asmlinkage void __sched schedule(void)
+asmlinkage __visible void __sched schedule(void)
{
struct task_struct *tsk = current;
@@ -2478,7 +2833,7 @@ asmlinkage void __sched schedule(void)
EXPORT_SYMBOL(schedule);
#ifdef CONFIG_CONTEXT_TRACKING
-asmlinkage void __sched schedule_user(void)
+asmlinkage __visible void __sched schedule_user(void)
{
/*
* If we come here after a random call to set_need_resched(),
@@ -2510,7 +2865,7 @@ void __sched schedule_preempt_disabled(void)
* off of preempt_enable. Kernel preemptions off return from interrupt
* occur there and call schedule directly.
*/
-asmlinkage void __sched notrace preempt_schedule(void)
+asmlinkage __visible void __sched notrace preempt_schedule(void)
{
/*
* If there is a non-zero preempt_count or interrupts are disabled,
@@ -2520,9 +2875,9 @@ asmlinkage void __sched notrace preempt_schedule(void)
return;
do {
- add_preempt_count_notrace(PREEMPT_ACTIVE);
+ __preempt_count_add(PREEMPT_ACTIVE);
__schedule();
- sub_preempt_count_notrace(PREEMPT_ACTIVE);
+ __preempt_count_sub(PREEMPT_ACTIVE);
/*
* Check again in case we missed a preemption opportunity
@@ -2531,7 +2886,9 @@ asmlinkage void __sched notrace preempt_schedule(void)
barrier();
} while (need_resched());
}
+NOKPROBE_SYMBOL(preempt_schedule);
EXPORT_SYMBOL(preempt_schedule);
+#endif /* CONFIG_PREEMPT */
/*
* this is the entry point to schedule() from kernel preemption
@@ -2539,22 +2896,21 @@ EXPORT_SYMBOL(preempt_schedule);
* Note, that this is called and return with irqs disabled. This will
* protect us against recursive calling from irq.
*/
-asmlinkage void __sched preempt_schedule_irq(void)
+asmlinkage __visible void __sched preempt_schedule_irq(void)
{
- struct thread_info *ti = current_thread_info();
enum ctx_state prev_state;
/* Catch callers which need to be fixed */
- BUG_ON(ti->preempt_count || !irqs_disabled());
+ BUG_ON(preempt_count() || !irqs_disabled());
prev_state = exception_enter();
do {
- add_preempt_count(PREEMPT_ACTIVE);
+ __preempt_count_add(PREEMPT_ACTIVE);
local_irq_enable();
__schedule();
local_irq_disable();
- sub_preempt_count(PREEMPT_ACTIVE);
+ __preempt_count_sub(PREEMPT_ACTIVE);
/*
* Check again in case we missed a preemption opportunity
@@ -2566,8 +2922,6 @@ asmlinkage void __sched preempt_schedule_irq(void)
exception_exit(prev_state);
}
-#endif /* CONFIG_PREEMPT */
-
int default_wake_function(wait_queue_t *curr, unsigned mode, int wake_flags,
void *key)
{
@@ -2575,439 +2929,6 @@ int default_wake_function(wait_queue_t *curr, unsigned mode, int wake_flags,
}
EXPORT_SYMBOL(default_wake_function);
-/*
- * The core wakeup function. Non-exclusive wakeups (nr_exclusive == 0) just
- * wake everything up. If it's an exclusive wakeup (nr_exclusive == small +ve
- * number) then we wake all the non-exclusive tasks and one exclusive task.
- *
- * There are circumstances in which we can try to wake a task which has already
- * started to run but is not in state TASK_RUNNING. try_to_wake_up() returns
- * zero in this (rare) case, and we handle it by continuing to scan the queue.
- */
-static void __wake_up_common(wait_queue_head_t *q, unsigned int mode,
- int nr_exclusive, int wake_flags, void *key)
-{
- wait_queue_t *curr, *next;
-
- list_for_each_entry_safe(curr, next, &q->task_list, task_list) {
- unsigned flags = curr->flags;
-
- if (curr->func(curr, mode, wake_flags, key) &&
- (flags & WQ_FLAG_EXCLUSIVE) && !--nr_exclusive)
- break;
- }
-}
-
-/**
- * __wake_up - wake up threads blocked on a waitqueue.
- * @q: the waitqueue
- * @mode: which threads
- * @nr_exclusive: how many wake-one or wake-many threads to wake up
- * @key: is directly passed to the wakeup function
- *
- * It may be assumed that this function implies a write memory barrier before
- * changing the task state if and only if any tasks are woken up.
- */
-void __wake_up(wait_queue_head_t *q, unsigned int mode,
- int nr_exclusive, void *key)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&q->lock, flags);
- __wake_up_common(q, mode, nr_exclusive, 0, key);
- spin_unlock_irqrestore(&q->lock, flags);
-}
-EXPORT_SYMBOL(__wake_up);
-
-/*
- * Same as __wake_up but called with the spinlock in wait_queue_head_t held.
- */
-void __wake_up_locked(wait_queue_head_t *q, unsigned int mode, int nr)
-{
- __wake_up_common(q, mode, nr, 0, NULL);
-}
-EXPORT_SYMBOL_GPL(__wake_up_locked);
-
-void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, void *key)
-{
- __wake_up_common(q, mode, 1, 0, key);
-}
-EXPORT_SYMBOL_GPL(__wake_up_locked_key);
-
-/**
- * __wake_up_sync_key - wake up threads blocked on a waitqueue.
- * @q: the waitqueue
- * @mode: which threads
- * @nr_exclusive: how many wake-one or wake-many threads to wake up
- * @key: opaque value to be passed to wakeup targets
- *
- * The sync wakeup differs that the waker knows that it will schedule
- * away soon, so while the target thread will be woken up, it will not
- * be migrated to another CPU - ie. the two threads are 'synchronized'
- * with each other. This can prevent needless bouncing between CPUs.
- *
- * On UP it can prevent extra preemption.
- *
- * It may be assumed that this function implies a write memory barrier before
- * changing the task state if and only if any tasks are woken up.
- */
-void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode,
- int nr_exclusive, void *key)
-{
- unsigned long flags;
- int wake_flags = WF_SYNC;
-
- if (unlikely(!q))
- return;
-
- if (unlikely(nr_exclusive != 1))
- wake_flags = 0;
-
- spin_lock_irqsave(&q->lock, flags);
- __wake_up_common(q, mode, nr_exclusive, wake_flags, key);
- spin_unlock_irqrestore(&q->lock, flags);
-}
-EXPORT_SYMBOL_GPL(__wake_up_sync_key);
-
-/*
- * __wake_up_sync - see __wake_up_sync_key()
- */
-void __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr_exclusive)
-{
- __wake_up_sync_key(q, mode, nr_exclusive, NULL);
-}
-EXPORT_SYMBOL_GPL(__wake_up_sync); /* For internal use only */
-
-/**
- * complete: - signals a single thread waiting on this completion
- * @x: holds the state of this particular completion
- *
- * This will wake up a single thread waiting on this completion. Threads will be
- * awakened in the same order in which they were queued.
- *
- * See also complete_all(), wait_for_completion() and related routines.
- *
- * It may be assumed that this function implies a write memory barrier before
- * changing the task state if and only if any tasks are woken up.
- */
-void complete(struct completion *x)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&x->wait.lock, flags);
- x->done++;
- __wake_up_common(&x->wait, TASK_NORMAL, 1, 0, NULL);
- spin_unlock_irqrestore(&x->wait.lock, flags);
-}
-EXPORT_SYMBOL(complete);
-
-/**
- * complete_all: - signals all threads waiting on this completion
- * @x: holds the state of this particular completion
- *
- * This will wake up all threads waiting on this particular completion event.
- *
- * It may be assumed that this function implies a write memory barrier before
- * changing the task state if and only if any tasks are woken up.
- */
-void complete_all(struct completion *x)
-{
- unsigned long flags;
-
- spin_lock_irqsave(&x->wait.lock, flags);
- x->done += UINT_MAX/2;
- __wake_up_common(&x->wait, TASK_NORMAL, 0, 0, NULL);
- spin_unlock_irqrestore(&x->wait.lock, flags);
-}
-EXPORT_SYMBOL(complete_all);
-
-static inline long __sched
-do_wait_for_common(struct completion *x,
- long (*action)(long), long timeout, int state)
-{
- if (!x->done) {
- DECLARE_WAITQUEUE(wait, current);
-
- __add_wait_queue_tail_exclusive(&x->wait, &wait);
- do {
- if (signal_pending_state(state, current)) {
- timeout = -ERESTARTSYS;
- break;
- }
- __set_current_state(state);
- spin_unlock_irq(&x->wait.lock);
- timeout = action(timeout);
- spin_lock_irq(&x->wait.lock);
- } while (!x->done && timeout);
- __remove_wait_queue(&x->wait, &wait);
- if (!x->done)
- return timeout;
- }
- x->done--;
- return timeout ?: 1;
-}
-
-static inline long __sched
-__wait_for_common(struct completion *x,
- long (*action)(long), long timeout, int state)
-{
- might_sleep();
-
- spin_lock_irq(&x->wait.lock);
- timeout = do_wait_for_common(x, action, timeout, state);
- spin_unlock_irq(&x->wait.lock);
- return timeout;
-}
-
-static long __sched
-wait_for_common(struct completion *x, long timeout, int state)
-{
- return __wait_for_common(x, schedule_timeout, timeout, state);
-}
-
-static long __sched
-wait_for_common_io(struct completion *x, long timeout, int state)
-{
- return __wait_for_common(x, io_schedule_timeout, timeout, state);
-}
-
-/**
- * wait_for_completion: - waits for completion of a task
- * @x: holds the state of this particular completion
- *
- * This waits to be signaled for completion of a specific task. It is NOT
- * interruptible and there is no timeout.
- *
- * See also similar routines (i.e. wait_for_completion_timeout()) with timeout
- * and interrupt capability. Also see complete().
- */
-void __sched wait_for_completion(struct completion *x)
-{
- wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_UNINTERRUPTIBLE);
-}
-EXPORT_SYMBOL(wait_for_completion);
-
-/**
- * wait_for_completion_timeout: - waits for completion of a task (w/timeout)
- * @x: holds the state of this particular completion
- * @timeout: timeout value in jiffies
- *
- * This waits for either a completion of a specific task to be signaled or for a
- * specified timeout to expire. The timeout is in jiffies. It is not
- * interruptible.
- *
- * Return: 0 if timed out, and positive (at least 1, or number of jiffies left
- * till timeout) if completed.
- */
-unsigned long __sched
-wait_for_completion_timeout(struct completion *x, unsigned long timeout)
-{
- return wait_for_common(x, timeout, TASK_UNINTERRUPTIBLE);
-}
-EXPORT_SYMBOL(wait_for_completion_timeout);
-
-/**
- * wait_for_completion_io: - waits for completion of a task
- * @x: holds the state of this particular completion
- *
- * This waits to be signaled for completion of a specific task. It is NOT
- * interruptible and there is no timeout. The caller is accounted as waiting
- * for IO.
- */
-void __sched wait_for_completion_io(struct completion *x)
-{
- wait_for_common_io(x, MAX_SCHEDULE_TIMEOUT, TASK_UNINTERRUPTIBLE);
-}
-EXPORT_SYMBOL(wait_for_completion_io);
-
-/**
- * wait_for_completion_io_timeout: - waits for completion of a task (w/timeout)
- * @x: holds the state of this particular completion
- * @timeout: timeout value in jiffies
- *
- * This waits for either a completion of a specific task to be signaled or for a
- * specified timeout to expire. The timeout is in jiffies. It is not
- * interruptible. The caller is accounted as waiting for IO.
- *
- * Return: 0 if timed out, and positive (at least 1, or number of jiffies left
- * till timeout) if completed.
- */
-unsigned long __sched
-wait_for_completion_io_timeout(struct completion *x, unsigned long timeout)
-{
- return wait_for_common_io(x, timeout, TASK_UNINTERRUPTIBLE);
-}
-EXPORT_SYMBOL(wait_for_completion_io_timeout);
-
-/**
- * wait_for_completion_interruptible: - waits for completion of a task (w/intr)
- * @x: holds the state of this particular completion
- *
- * This waits for completion of a specific task to be signaled. It is
- * interruptible.
- *
- * Return: -ERESTARTSYS if interrupted, 0 if completed.
- */
-int __sched wait_for_completion_interruptible(struct completion *x)
-{
- long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_INTERRUPTIBLE);
- if (t == -ERESTARTSYS)
- return t;
- return 0;
-}
-EXPORT_SYMBOL(wait_for_completion_interruptible);
-
-/**
- * wait_for_completion_interruptible_timeout: - waits for completion (w/(to,intr))
- * @x: holds the state of this particular completion
- * @timeout: timeout value in jiffies
- *
- * This waits for either a completion of a specific task to be signaled or for a
- * specified timeout to expire. It is interruptible. The timeout is in jiffies.
- *
- * Return: -ERESTARTSYS if interrupted, 0 if timed out, positive (at least 1,
- * or number of jiffies left till timeout) if completed.
- */
-long __sched
-wait_for_completion_interruptible_timeout(struct completion *x,
- unsigned long timeout)
-{
- return wait_for_common(x, timeout, TASK_INTERRUPTIBLE);
-}
-EXPORT_SYMBOL(wait_for_completion_interruptible_timeout);
-
-/**
- * wait_for_completion_killable: - waits for completion of a task (killable)
- * @x: holds the state of this particular completion
- *
- * This waits to be signaled for completion of a specific task. It can be
- * interrupted by a kill signal.
- *
- * Return: -ERESTARTSYS if interrupted, 0 if completed.
- */
-int __sched wait_for_completion_killable(struct completion *x)
-{
- long t = wait_for_common(x, MAX_SCHEDULE_TIMEOUT, TASK_KILLABLE);
- if (t == -ERESTARTSYS)
- return t;
- return 0;
-}
-EXPORT_SYMBOL(wait_for_completion_killable);
-
-/**
- * wait_for_completion_killable_timeout: - waits for completion of a task (w/(to,killable))
- * @x: holds the state of this particular completion
- * @timeout: timeout value in jiffies
- *
- * This waits for either a completion of a specific task to be
- * signaled or for a specified timeout to expire. It can be
- * interrupted by a kill signal. The timeout is in jiffies.
- *
- * Return: -ERESTARTSYS if interrupted, 0 if timed out, positive (at least 1,
- * or number of jiffies left till timeout) if completed.
- */
-long __sched
-wait_for_completion_killable_timeout(struct completion *x,
- unsigned long timeout)
-{
- return wait_for_common(x, timeout, TASK_KILLABLE);
-}
-EXPORT_SYMBOL(wait_for_completion_killable_timeout);
-
-/**
- * try_wait_for_completion - try to decrement a completion without blocking
- * @x: completion structure
- *
- * Return: 0 if a decrement cannot be done without blocking
- * 1 if a decrement succeeded.
- *
- * If a completion is being used as a counting completion,
- * attempt to decrement the counter without blocking. This
- * enables us to avoid waiting if the resource the completion
- * is protecting is not available.
- */
-bool try_wait_for_completion(struct completion *x)
-{
- unsigned long flags;
- int ret = 1;
-
- spin_lock_irqsave(&x->wait.lock, flags);
- if (!x->done)
- ret = 0;
- else
- x->done--;
- spin_unlock_irqrestore(&x->wait.lock, flags);
- return ret;
-}
-EXPORT_SYMBOL(try_wait_for_completion);
-
-/**
- * completion_done - Test to see if a completion has any waiters
- * @x: completion structure
- *
- * Return: 0 if there are waiters (wait_for_completion() in progress)
- * 1 if there are no waiters.
- *
- */
-bool completion_done(struct completion *x)
-{
- unsigned long flags;
- int ret = 1;
-
- spin_lock_irqsave(&x->wait.lock, flags);
- if (!x->done)
- ret = 0;
- spin_unlock_irqrestore(&x->wait.lock, flags);
- return ret;
-}
-EXPORT_SYMBOL(completion_done);
-
-static long __sched
-sleep_on_common(wait_queue_head_t *q, int state, long timeout)
-{
- unsigned long flags;
- wait_queue_t wait;
-
- init_waitqueue_entry(&wait, current);
-
- __set_current_state(state);
-
- spin_lock_irqsave(&q->lock, flags);
- __add_wait_queue(q, &wait);
- spin_unlock(&q->lock);
- timeout = schedule_timeout(timeout);
- spin_lock_irq(&q->lock);
- __remove_wait_queue(q, &wait);
- spin_unlock_irqrestore(&q->lock, flags);
-
- return timeout;
-}
-
-void __sched interruptible_sleep_on(wait_queue_head_t *q)
-{
- sleep_on_common(q, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
-}
-EXPORT_SYMBOL(interruptible_sleep_on);
-
-long __sched
-interruptible_sleep_on_timeout(wait_queue_head_t *q, long timeout)
-{
- return sleep_on_common(q, TASK_INTERRUPTIBLE, timeout);
-}
-EXPORT_SYMBOL(interruptible_sleep_on_timeout);
-
-void __sched sleep_on(wait_queue_head_t *q)
-{
- sleep_on_common(q, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
-}
-EXPORT_SYMBOL(sleep_on);
-
-long __sched sleep_on_timeout(wait_queue_head_t *q, long timeout)
-{
- return sleep_on_common(q, TASK_UNINTERRUPTIBLE, timeout);
-}
-EXPORT_SYMBOL(sleep_on_timeout);
-
#ifdef CONFIG_RT_MUTEXES
/*
@@ -3018,15 +2939,16 @@ EXPORT_SYMBOL(sleep_on_timeout);
* This function changes the 'effective' priority of a task. It does
* not touch ->normal_prio like __setscheduler().
*
- * Used by the rt_mutex code to implement priority inheritance logic.
+ * Used by the rt_mutex code to implement priority inheritance
+ * logic. Call site only calls if the priority of the task changed.
*/
void rt_mutex_setprio(struct task_struct *p, int prio)
{
- int oldprio, on_rq, running;
+ int oldprio, on_rq, running, enqueue_flag = 0;
struct rq *rq;
const struct sched_class *prev_class;
- BUG_ON(prio < 0 || prio > MAX_PRIO);
+ BUG_ON(prio > MAX_PRIO);
rq = __task_rq_lock(p);
@@ -3049,6 +2971,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
}
trace_sched_pi_setprio(p, prio);
+ p->pi_top_task = rt_mutex_get_top_task(p);
oldprio = p->prio;
prev_class = p->sched_class;
on_rq = p->on_rq;
@@ -3058,30 +2981,56 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
if (running)
p->sched_class->put_prev_task(rq, p);
- if (rt_prio(prio))
+ /*
+ * Boosting condition are:
+ * 1. -rt task is running and holds mutex A
+ * --> -dl task blocks on mutex A
+ *
+ * 2. -dl task is running and holds mutex A
+ * --> -dl task blocks on mutex A and could preempt the
+ * running task
+ */
+ if (dl_prio(prio)) {
+ if (!dl_prio(p->normal_prio) || (p->pi_top_task &&
+ dl_entity_preempt(&p->pi_top_task->dl, &p->dl))) {
+ p->dl.dl_boosted = 1;
+ p->dl.dl_throttled = 0;
+ enqueue_flag = ENQUEUE_REPLENISH;
+ } else
+ p->dl.dl_boosted = 0;
+ p->sched_class = &dl_sched_class;
+ } else if (rt_prio(prio)) {
+ if (dl_prio(oldprio))
+ p->dl.dl_boosted = 0;
+ if (oldprio < prio)
+ enqueue_flag = ENQUEUE_HEAD;
p->sched_class = &rt_sched_class;
- else
+ } else {
+ if (dl_prio(oldprio))
+ p->dl.dl_boosted = 0;
p->sched_class = &fair_sched_class;
+ }
p->prio = prio;
if (running)
p->sched_class->set_curr_task(rq);
if (on_rq)
- enqueue_task(rq, p, oldprio < prio ? ENQUEUE_HEAD : 0);
+ enqueue_task(rq, p, enqueue_flag);
check_class_changed(rq, p, prev_class, oldprio);
out_unlock:
__task_rq_unlock(rq);
}
#endif
+
void set_user_nice(struct task_struct *p, long nice)
{
int old_prio, delta, on_rq;
unsigned long flags;
struct rq *rq;
- if (TASK_NICE(p) == nice || nice < -20 || nice > 19)
+ if (task_nice(p) == nice || nice < MIN_NICE || nice > MAX_NICE)
return;
/*
* We have to be careful, if called from sys_setpriority(),
@@ -3092,9 +3041,9 @@ void set_user_nice(struct task_struct *p, long nice)
* The RT priorities are set via sched_setscheduler(), but we still
* allow the 'normal' nice value to be set - but as expected
* it wont have any effect on scheduling until the task is
- * SCHED_FIFO/SCHED_RR:
+ * SCHED_DEADLINE, SCHED_FIFO or SCHED_RR:
*/
- if (task_has_rt_policy(p)) {
+ if (task_has_dl_policy(p) || task_has_rt_policy(p)) {
p->static_prio = NICE_TO_PRIO(nice);
goto out_unlock;
}
@@ -3130,7 +3079,7 @@ EXPORT_SYMBOL(set_user_nice);
int can_nice(const struct task_struct *p, const int nice)
{
/* convert nice value [19,-20] to rlimit style value [1,40] */
- int nice_rlim = 20 - nice;
+ int nice_rlim = nice_to_rlimit(nice);
return (nice_rlim <= task_rlimit(p, RLIMIT_NICE) ||
capable(CAP_SYS_NICE));
@@ -3154,17 +3103,10 @@ SYSCALL_DEFINE1(nice, int, increment)
* We don't have to worry. Conceptually one call occurs first
* and we have a single winner.
*/
- if (increment < -40)
- increment = -40;
- if (increment > 40)
- increment = 40;
-
- nice = TASK_NICE(current) + increment;
- if (nice < -20)
- nice = -20;
- if (nice > 19)
- nice = 19;
+ increment = clamp(increment, -NICE_WIDTH, NICE_WIDTH);
+ nice = task_nice(current) + increment;
+ nice = clamp_val(nice, MIN_NICE, MAX_NICE);
if (increment < 0 && !can_nice(current, nice))
return -EPERM;
@@ -3192,18 +3134,6 @@ int task_prio(const struct task_struct *p)
}
/**
- * task_nice - return the nice value of a given task.
- * @p: the task in question.
- *
- * Return: The nice value [ -20 ... 0 ... 19 ].
- */
-int task_nice(const struct task_struct *p)
-{
- return TASK_NICE(p);
-}
-EXPORT_SYMBOL(task_nice);
-
-/**
* idle_cpu - is a given cpu idle currently?
* @cpu: the processor in question.
*
@@ -3249,20 +3179,126 @@ static struct task_struct *find_process_by_pid(pid_t pid)
return pid ? find_task_by_vpid(pid) : current;
}
-/* Actually do priority change: must hold rq lock. */
+/*
+ * 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
-__setscheduler(struct rq *rq, struct task_struct *p, int policy, int prio)
+__setparam_dl(struct task_struct *p, const struct sched_attr *attr)
{
+ struct sched_dl_entity *dl_se = &p->dl;
+
+ init_dl_task_timer(dl_se);
+ 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_throttled = 0;
+ dl_se->dl_new = 1;
+ dl_se->dl_yielded = 0;
+}
+
+static void __setscheduler_params(struct task_struct *p,
+ const struct sched_attr *attr)
+{
+ int policy = attr->sched_policy;
+
+ if (policy == -1) /* setparam */
+ policy = p->policy;
+
p->policy = policy;
- p->rt_priority = prio;
+
+ if (dl_policy(policy))
+ __setparam_dl(p, attr);
+ else if (fair_policy(policy))
+ p->static_prio = NICE_TO_PRIO(attr->sched_nice);
+
+ /*
+ * __sched_setscheduler() ensures attr->sched_priority == 0 when
+ * !rt_policy. Always setting this ensures that things like
+ * getparam()/getattr() don't report silly values for !rt tasks.
+ */
+ p->rt_priority = attr->sched_priority;
p->normal_prio = normal_prio(p);
- /* we are holding p->pi_lock already */
- p->prio = rt_mutex_getprio(p);
- if (rt_prio(p->prio))
+ set_load_weight(p);
+}
+
+/* Actually do priority change: must hold pi & rq lock. */
+static void __setscheduler(struct rq *rq, struct task_struct *p,
+ const struct sched_attr *attr)
+{
+ __setscheduler_params(p, attr);
+
+ /*
+ * If we get here, there was no pi waiters boosting the
+ * task. It is safe to use the normal prio.
+ */
+ p->prio = normal_prio(p);
+
+ if (dl_prio(p->prio))
+ p->sched_class = &dl_sched_class;
+ else if (rt_prio(p->prio))
p->sched_class = &rt_sched_class;
else
p->sched_class = &fair_sched_class;
- set_load_weight(p);
+}
+
+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;
}
/*
@@ -3281,10 +3317,14 @@ static bool check_same_owner(struct task_struct *p)
return match;
}
-static int __sched_setscheduler(struct task_struct *p, int policy,
- const struct sched_param *param, bool user)
+static int __sched_setscheduler(struct task_struct *p,
+ const struct sched_attr *attr,
+ bool user)
{
+ int newprio = dl_policy(attr->sched_policy) ? MAX_DL_PRIO - 1 :
+ MAX_RT_PRIO - 1 - attr->sched_priority;
int retval, oldprio, oldpolicy = -1, on_rq, running;
+ int policy = attr->sched_policy;
unsigned long flags;
const struct sched_class *prev_class;
struct rq *rq;
@@ -3298,31 +3338,40 @@ recheck:
reset_on_fork = p->sched_reset_on_fork;
policy = oldpolicy = p->policy;
} else {
- reset_on_fork = !!(policy & SCHED_RESET_ON_FORK);
- policy &= ~SCHED_RESET_ON_FORK;
+ reset_on_fork = !!(attr->sched_flags & SCHED_FLAG_RESET_ON_FORK);
- if (policy != SCHED_FIFO && policy != SCHED_RR &&
+ if (policy != SCHED_DEADLINE &&
+ policy != SCHED_FIFO && policy != SCHED_RR &&
policy != SCHED_NORMAL && policy != SCHED_BATCH &&
policy != SCHED_IDLE)
return -EINVAL;
}
+ if (attr->sched_flags & ~(SCHED_FLAG_RESET_ON_FORK))
+ return -EINVAL;
+
/*
* Valid priorities for SCHED_FIFO and SCHED_RR are
* 1..MAX_USER_RT_PRIO-1, valid priority for SCHED_NORMAL,
* SCHED_BATCH and SCHED_IDLE is 0.
*/
- if (param->sched_priority < 0 ||
- (p->mm && param->sched_priority > MAX_USER_RT_PRIO-1) ||
- (!p->mm && param->sched_priority > MAX_RT_PRIO-1))
+ if ((p->mm && attr->sched_priority > MAX_USER_RT_PRIO-1) ||
+ (!p->mm && attr->sched_priority > MAX_RT_PRIO-1))
return -EINVAL;
- if (rt_policy(policy) != (param->sched_priority != 0))
+ if ((dl_policy(policy) && !__checkparam_dl(attr)) ||
+ (rt_policy(policy) != (attr->sched_priority != 0)))
return -EINVAL;
/*
* Allow unprivileged RT tasks to decrease priority:
*/
if (user && !capable(CAP_SYS_NICE)) {
+ if (fair_policy(policy)) {
+ if (attr->sched_nice < task_nice(p) &&
+ !can_nice(p, attr->sched_nice))
+ return -EPERM;
+ }
+
if (rt_policy(policy)) {
unsigned long rlim_rtprio =
task_rlimit(p, RLIMIT_RTPRIO);
@@ -3332,17 +3381,26 @@ recheck:
return -EPERM;
/* can't increase priority */
- if (param->sched_priority > p->rt_priority &&
- param->sched_priority > rlim_rtprio)
+ if (attr->sched_priority > p->rt_priority &&
+ attr->sched_priority > rlim_rtprio)
return -EPERM;
}
+ /*
+ * Can't set/change SCHED_DEADLINE policy at all for now
+ * (safest behavior); in the future we would like to allow
+ * unprivileged DL tasks to increase their relative deadline
+ * or reduce their runtime (both ways reducing utilization)
+ */
+ if (dl_policy(policy))
+ return -EPERM;
+
/*
* Treat SCHED_IDLE as nice 20. Only allow a switch to
* SCHED_NORMAL if the RLIMIT_NICE would normally permit it.
*/
if (p->policy == SCHED_IDLE && policy != SCHED_IDLE) {
- if (!can_nice(p, TASK_NICE(p)))
+ if (!can_nice(p, task_nice(p)))
return -EPERM;
}
@@ -3379,16 +3437,25 @@ recheck:
}
/*
- * If not changing anything there's no need to proceed further:
+ * If not changing anything there's no need to proceed further,
+ * but store a possible modification of reset_on_fork.
*/
- if (unlikely(policy == p->policy && (!rt_policy(policy) ||
- param->sched_priority == p->rt_priority))) {
+ if (unlikely(policy == p->policy)) {
+ if (fair_policy(policy) && attr->sched_nice != task_nice(p))
+ goto change;
+ if (rt_policy(policy) && attr->sched_priority != p->rt_priority)
+ goto change;
+ if (dl_policy(policy))
+ goto change;
+
+ p->sched_reset_on_fork = reset_on_fork;
task_rq_unlock(rq, p, &flags);
return 0;
}
+change:
-#ifdef CONFIG_RT_GROUP_SCHED
if (user) {
+#ifdef CONFIG_RT_GROUP_SCHED
/*
* Do not allow realtime tasks into groups that have no runtime
* assigned.
@@ -3399,8 +3466,24 @@ recheck:
task_rq_unlock(rq, p, &flags);
return -EPERM;
}
- }
#endif
+#ifdef CONFIG_SMP
+ if (dl_bandwidth_enabled() && dl_policy(policy)) {
+ cpumask_t *span = rq->rd->span;
+
+ /*
+ * Don't allow tasks with an affinity mask smaller than
+ * the entire root_domain to become SCHED_DEADLINE. We
+ * will also fail if there's no bandwidth available.
+ */
+ if (!cpumask_subset(span, &p->cpus_allowed) ||
+ rq->rd->dl_bw.bw == 0) {
+ task_rq_unlock(rq, p, &flags);
+ return -EPERM;
+ }
+ }
+#endif
+ }
/* recheck policy now with rq lock held */
if (unlikely(oldpolicy != -1 && oldpolicy != p->policy)) {
@@ -3408,6 +3491,35 @@ recheck:
task_rq_unlock(rq, p, &flags);
goto recheck;
}
+
+ /*
+ * If setscheduling to SCHED_DEADLINE (or changing the parameters
+ * 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)) {
+ task_rq_unlock(rq, p, &flags);
+ return -EBUSY;
+ }
+
+ p->sched_reset_on_fork = reset_on_fork;
+ oldprio = p->prio;
+
+ /*
+ * Special case for priority boosted tasks.
+ *
+ * If the new priority is lower or equal (user space view)
+ * than the current (boosted) priority, we just store the new
+ * normal parameters and do not touch the scheduler class and
+ * the runqueue. This will be done when the task deboost
+ * itself.
+ */
+ if (rt_mutex_check_prio(p, newprio)) {
+ __setscheduler_params(p, attr);
+ task_rq_unlock(rq, p, &flags);
+ return 0;
+ }
+
on_rq = p->on_rq;
running = task_current(rq, p);
if (on_rq)
@@ -3415,16 +3527,18 @@ recheck:
if (running)
p->sched_class->put_prev_task(rq, p);
- p->sched_reset_on_fork = reset_on_fork;
-
- oldprio = p->prio;
prev_class = p->sched_class;
- __setscheduler(rq, p, policy, param->sched_priority);
+ __setscheduler(rq, p, attr);
if (running)
p->sched_class->set_curr_task(rq);
- if (on_rq)
- enqueue_task(rq, p, 0);
+ if (on_rq) {
+ /*
+ * We enqueue to tail when the priority of a task is
+ * increased (user space view).
+ */
+ enqueue_task(rq, p, oldprio <= p->prio ? ENQUEUE_HEAD : 0);
+ }
check_class_changed(rq, p, prev_class, oldprio);
task_rq_unlock(rq, p, &flags);
@@ -3434,6 +3548,26 @@ recheck:
return 0;
}
+static int _sched_setscheduler(struct task_struct *p, int policy,
+ const struct sched_param *param, bool check)
+{
+ struct sched_attr attr = {
+ .sched_policy = policy,
+ .sched_priority = param->sched_priority,
+ .sched_nice = PRIO_TO_NICE(p->static_prio),
+ };
+
+ /*
+ * Fixup the legacy SCHED_RESET_ON_FORK hack
+ */
+ if (policy & SCHED_RESET_ON_FORK) {
+ attr.sched_flags |= SCHED_FLAG_RESET_ON_FORK;
+ policy &= ~SCHED_RESET_ON_FORK;
+ attr.sched_policy = policy;
+ }
+
+ return __sched_setscheduler(p, &attr, check);
+}
/**
* sched_setscheduler - change the scheduling policy and/or RT priority of a thread.
* @p: the task in question.
@@ -3447,10 +3581,16 @@ recheck:
int sched_setscheduler(struct task_struct *p, int policy,
const struct sched_param *param)
{
- return __sched_setscheduler(p, policy, param, true);
+ return _sched_setscheduler(p, policy, param, true);
}
EXPORT_SYMBOL_GPL(sched_setscheduler);
+int sched_setattr(struct task_struct *p, const struct sched_attr *attr)
+{
+ return __sched_setscheduler(p, attr, true);
+}
+EXPORT_SYMBOL_GPL(sched_setattr);
+
/**
* sched_setscheduler_nocheck - change the scheduling policy and/or RT priority of a thread from kernelspace.
* @p: the task in question.
@@ -3467,7 +3607,7 @@ EXPORT_SYMBOL_GPL(sched_setscheduler);
int sched_setscheduler_nocheck(struct task_struct *p, int policy,
const struct sched_param *param)
{
- return __sched_setscheduler(p, policy, param, false);
+ return _sched_setscheduler(p, policy, param, false);
}
static int
@@ -3492,6 +3632,77 @@ do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param)
return retval;
}
+/*
+ * Mimics kernel/events/core.c perf_copy_attr().
+ */
+static int sched_copy_attr(struct sched_attr __user *uattr,
+ struct sched_attr *attr)
+{
+ u32 size;
+ int ret;
+
+ if (!access_ok(VERIFY_WRITE, uattr, SCHED_ATTR_SIZE_VER0))
+ return -EFAULT;
+
+ /*
+ * zero the full structure, so that a short copy will be nice.
+ */
+ memset(attr, 0, sizeof(*attr));
+
+ ret = get_user(size, &uattr->size);
+ if (ret)
+ return ret;
+
+ if (size > PAGE_SIZE) /* silly large */
+ goto err_size;
+
+ if (!size) /* abi compat */
+ size = SCHED_ATTR_SIZE_VER0;
+
+ if (size < SCHED_ATTR_SIZE_VER0)
+ goto err_size;
+
+ /*
+ * If we're handed a bigger struct than we know of,
+ * ensure all the unknown bits are 0 - i.e. new
+ * user-space does not rely on any kernel feature
+ * extensions we dont know about yet.
+ */
+ if (size > sizeof(*attr)) {
+ unsigned char __user *addr;
+ unsigned char __user *end;
+ unsigned char val;
+
+ addr = (void __user *)uattr + sizeof(*attr);
+ end = (void __user *)uattr + size;
+
+ for (; addr < end; addr++) {
+ ret = get_user(val, addr);
+ if (ret)
+ return ret;
+ if (val)
+ goto err_size;
+ }
+ size = sizeof(*attr);
+ }
+
+ ret = copy_from_user(attr, uattr, size);
+ if (ret)
+ return -EFAULT;
+
+ /*
+ * XXX: do we want to be lenient like existing syscalls; or do we want
+ * to be strict and return an error on out-of-bounds values?
+ */
+ attr->sched_nice = clamp(attr->sched_nice, MIN_NICE, MAX_NICE);
+
+ return 0;
+
+err_size:
+ put_user(sizeof(*attr), &uattr->size);
+ return -E2BIG;
+}
+
/**
* sys_sched_setscheduler - set/change the scheduler policy and RT priority
* @pid: the pid in question.
@@ -3523,6 +3734,39 @@ SYSCALL_DEFINE2(sched_setparam, pid_t, pid, struct sched_param __user *, param)
}
/**
+ * sys_sched_setattr - same as above, but with extended sched_attr
+ * @pid: the pid in question.
+ * @uattr: structure containing the extended parameters.
+ * @flags: for future extension.
+ */
+SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr,
+ unsigned int, flags)
+{
+ struct sched_attr attr;
+ struct task_struct *p;
+ int retval;
+
+ if (!uattr || pid < 0 || flags)
+ return -EINVAL;
+
+ retval = sched_copy_attr(uattr, &attr);
+ if (retval)
+ return retval;
+
+ if ((int)attr.sched_policy < 0)
+ return -EINVAL;
+
+ rcu_read_lock();
+ retval = -ESRCH;
+ p = find_process_by_pid(pid);
+ if (p != NULL)
+ retval = sched_setattr(p, &attr);
+ rcu_read_unlock();
+
+ return retval;
+}
+
+/**
* sys_sched_getscheduler - get the policy (scheduling class) of a thread
* @pid: the pid in question.
*
@@ -3560,7 +3804,7 @@ SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid)
*/
SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
{
- struct sched_param lp;
+ struct sched_param lp = { .sched_priority = 0 };
struct task_struct *p;
int retval;
@@ -3577,7 +3821,8 @@ SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param)
if (retval)
goto out_unlock;
- lp.sched_priority = p->rt_priority;
+ if (task_has_rt_policy(p))
+ lp.sched_priority = p->rt_priority;
rcu_read_unlock();
/*
@@ -3592,19 +3837,103 @@ out_unlock:
return retval;
}
+static int sched_read_attr(struct sched_attr __user *uattr,
+ struct sched_attr *attr,
+ unsigned int usize)
+{
+ int ret;
+
+ if (!access_ok(VERIFY_WRITE, uattr, usize))
+ return -EFAULT;
+
+ /*
+ * If we're handed a smaller struct than we know of,
+ * ensure all the unknown bits are 0 - i.e. old
+ * user-space does not get uncomplete information.
+ */
+ if (usize < sizeof(*attr)) {
+ unsigned char *addr;
+ unsigned char *end;
+
+ addr = (void *)attr + usize;
+ end = (void *)attr + sizeof(*attr);
+
+ for (; addr < end; addr++) {
+ if (*addr)
+ return -EFBIG;
+ }
+
+ attr->size = usize;
+ }
+
+ ret = copy_to_user(uattr, attr, attr->size);
+ if (ret)
+ return -EFAULT;
+
+ return 0;
+}
+
+/**
+ * sys_sched_getattr - similar to sched_getparam, but with sched_attr
+ * @pid: the pid in question.
+ * @uattr: structure containing the extended parameters.
+ * @size: sizeof(attr) for fwd/bwd comp.
+ * @flags: for future extension.
+ */
+SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr,
+ unsigned int, size, unsigned int, flags)
+{
+ struct sched_attr attr = {
+ .size = sizeof(struct sched_attr),
+ };
+ struct task_struct *p;
+ int retval;
+
+ if (!uattr || pid < 0 || size > PAGE_SIZE ||
+ size < SCHED_ATTR_SIZE_VER0 || flags)
+ return -EINVAL;
+
+ rcu_read_lock();
+ p = find_process_by_pid(pid);
+ retval = -ESRCH;
+ if (!p)
+ goto out_unlock;
+
+ retval = security_task_getscheduler(p);
+ if (retval)
+ goto out_unlock;
+
+ attr.sched_policy = p->policy;
+ if (p->sched_reset_on_fork)
+ attr.sched_flags |= SCHED_FLAG_RESET_ON_FORK;
+ if (task_has_dl_policy(p))
+ __getparam_dl(p, &attr);
+ else if (task_has_rt_policy(p))
+ attr.sched_priority = p->rt_priority;
+ else
+ attr.sched_nice = task_nice(p);
+
+ rcu_read_unlock();
+
+ retval = sched_read_attr(uattr, &attr, size);
+ return retval;
+
+out_unlock:
+ rcu_read_unlock();
+ return retval;
+}
+
long sched_setaffinity(pid_t pid, const struct cpumask *in_mask)
{
cpumask_var_t cpus_allowed, new_mask;
struct task_struct *p;
int retval;
- get_online_cpus();
rcu_read_lock();
p = find_process_by_pid(pid);
if (!p) {
rcu_read_unlock();
- put_online_cpus();
return -ESRCH;
}
@@ -3638,8 +3967,26 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask)
if (retval)
goto out_unlock;
+
cpuset_cpus_allowed(p, cpus_allowed);
cpumask_and(new_mask, in_mask, cpus_allowed);
+
+ /*
+ * Since bandwidth control happens on root_domain basis,
+ * if admission test is enabled, we only admit -deadline
+ * tasks allowed to run on all the CPUs in the task's
+ * root_domain.
+ */
+#ifdef CONFIG_SMP
+ if (task_has_dl_policy(p)) {
+ const struct cpumask *span = task_rq(p)->rd->span;
+
+ if (dl_bandwidth_enabled() && !cpumask_subset(span, new_mask)) {
+ retval = -EBUSY;
+ goto out_unlock;
+ }
+ }
+#endif
again:
retval = set_cpus_allowed_ptr(p, new_mask);
@@ -3661,7 +4008,6 @@ out_free_cpus_allowed:
free_cpumask_var(cpus_allowed);
out_put_task:
put_task_struct(p);
- put_online_cpus();
return retval;
}
@@ -3706,7 +4052,6 @@ long sched_getaffinity(pid_t pid, struct cpumask *mask)
unsigned long flags;
int retval;
- get_online_cpus();
rcu_read_lock();
retval = -ESRCH;
@@ -3719,12 +4064,11 @@ long sched_getaffinity(pid_t pid, struct cpumask *mask)
goto out_unlock;
raw_spin_lock_irqsave(&p->pi_lock, flags);
- cpumask_and(mask, &p->cpus_allowed, cpu_online_mask);
+ cpumask_and(mask, &p->cpus_allowed, cpu_active_mask);
raw_spin_unlock_irqrestore(&p->pi_lock, flags);
out_unlock:
rcu_read_unlock();
- put_online_cpus();
return retval;
}
@@ -3794,16 +4138,11 @@ SYSCALL_DEFINE0(sched_yield)
return 0;
}
-static inline int should_resched(void)
-{
- return need_resched() && !(preempt_count() & PREEMPT_ACTIVE);
-}
-
static void __cond_resched(void)
{
- add_preempt_count(PREEMPT_ACTIVE);
+ __preempt_count_add(PREEMPT_ACTIVE);
__schedule();
- sub_preempt_count(PREEMPT_ACTIVE);
+ __preempt_count_sub(PREEMPT_ACTIVE);
}
int __sched _cond_resched(void)
@@ -3902,7 +4241,7 @@ EXPORT_SYMBOL(yield);
* false (0) if we failed to boost the target.
* -ESRCH if there's no task to yield to.
*/
-bool __sched yield_to(struct task_struct *p, bool preempt)
+int __sched yield_to(struct task_struct *p, bool preempt)
{
struct task_struct *curr = current;
struct rq *rq, *p_rq;
@@ -3924,7 +4263,7 @@ again:
}
double_rq_lock(rq, p_rq);
- while (task_rq(p) != p_rq) {
+ if (task_rq(p) != p_rq) {
double_rq_unlock(rq, p_rq);
goto again;
}
@@ -4013,6 +4352,7 @@ SYSCALL_DEFINE1(sched_get_priority_max, int, policy)
case SCHED_RR:
ret = MAX_USER_RT_PRIO-1;
break;
+ case SCHED_DEADLINE:
case SCHED_NORMAL:
case SCHED_BATCH:
case SCHED_IDLE:
@@ -4039,6 +4379,7 @@ SYSCALL_DEFINE1(sched_get_priority_min, int, policy)
case SCHED_RR:
ret = 1;
break;
+ case SCHED_DEADLINE:
case SCHED_NORMAL:
case SCHED_BATCH:
case SCHED_IDLE:
@@ -4082,7 +4423,9 @@ SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
goto out_unlock;
rq = task_rq_lock(p, &flags);
- time_slice = p->sched_class->get_rr_interval(rq, p);
+ time_slice = 0;
+ if (p->sched_class->get_rr_interval)
+ time_slice = p->sched_class->get_rr_interval(rq, p);
task_rq_unlock(rq, p, &flags);
rcu_read_unlock();
@@ -4186,7 +4529,7 @@ void init_idle(struct task_struct *idle, int cpu)
raw_spin_lock_irqsave(&rq->lock, flags);
- __sched_fork(idle);
+ __sched_fork(0, idle);
idle->state = TASK_RUNNING;
idle->se.exec_start = sched_clock();
@@ -4206,13 +4549,14 @@ void init_idle(struct task_struct *idle, int cpu)
rcu_read_unlock();
rq->curr = rq->idle = idle;
+ idle->on_rq = 1;
#if defined(CONFIG_SMP)
idle->on_cpu = 1;
#endif
raw_spin_unlock_irqrestore(&rq->lock, flags);
/* Set the preempt count _outside_ the spinlocks! */
- task_thread_info(idle)->preempt_count = 0;
+ init_idle_preempt_count(idle, cpu);
/*
* The idle tasks have their own, simple scheduling class:
@@ -4346,6 +4690,54 @@ fail:
return ret;
}
+#ifdef CONFIG_NUMA_BALANCING
+/* Migrate current task p to target_cpu */
+int migrate_task_to(struct task_struct *p, int target_cpu)
+{
+ struct migration_arg arg = { p, target_cpu };
+ int curr_cpu = task_cpu(p);
+
+ if (curr_cpu == target_cpu)
+ return 0;
+
+ if (!cpumask_test_cpu(target_cpu, tsk_cpus_allowed(p)))
+ return -EINVAL;
+
+ /* TODO: This is not properly updating schedstats */
+
+ trace_sched_move_numa(p, curr_cpu, target_cpu);
+ return stop_one_cpu(curr_cpu, migration_cpu_stop, &arg);
+}
+
+/*
+ * Requeue a task on a given node and accurately track the number of NUMA
+ * tasks on the runqueues
+ */
+void sched_setnuma(struct task_struct *p, int nid)
+{
+ struct rq *rq;
+ unsigned long flags;
+ bool on_rq, running;
+
+ rq = task_rq_lock(p, &flags);
+ on_rq = p->on_rq;
+ running = task_current(rq, p);
+
+ if (on_rq)
+ dequeue_task(rq, p, 0);
+ if (running)
+ p->sched_class->put_prev_task(rq, p);
+
+ p->numa_preferred_nid = nid;
+
+ if (running)
+ p->sched_class->set_curr_task(rq);
+ if (on_rq)
+ enqueue_task(rq, p, 0);
+ task_rq_unlock(rq, p, &flags);
+}
+#endif
+
/*
* migration_cpu_stop - this will be executed by a highprio stopper thread
* and performs thread migration by bumping thread off CPU then
@@ -4377,8 +4769,10 @@ void idle_task_exit(void)
BUG_ON(cpu_online(smp_processor_id()));
- if (mm != &init_mm)
+ if (mm != &init_mm) {
switch_mm(mm, &init_mm, current);
+ finish_arch_post_lock_switch();
+ }
mmdrop(mm);
}
@@ -4396,6 +4790,22 @@ static void calc_load_migrate(struct rq *rq)
atomic_long_add(delta, &calc_load_tasks);
}
+static void put_prev_task_fake(struct rq *rq, struct task_struct *prev)
+{
+}
+
+static const struct sched_class fake_sched_class = {
+ .put_prev_task = put_prev_task_fake,
+};
+
+static struct task_struct fake_task = {
+ /*
+ * Avoid pull_{rt,dl}_task()
+ */
+ .prio = MAX_PRIO + 1,
+ .sched_class = &fake_sched_class,
+};
+
/*
* Migrate all tasks from the rq, sleeping tasks will be migrated by
* try_to_wake_up()->select_task_rq().
@@ -4436,7 +4846,7 @@ static void migrate_tasks(unsigned int dead_cpu)
if (rq->nr_running == 1)
break;
- next = pick_next_task(rq);
+ next = pick_next_task(rq, &fake_task);
BUG_ON(!next);
next->sched_class->put_prev_task(rq, next);
@@ -4526,7 +4936,7 @@ set_table_entry(struct ctl_table *entry,
static struct ctl_table *
sd_alloc_ctl_domain_table(struct sched_domain *sd)
{
- struct ctl_table *table = sd_alloc_ctl_entry(13);
+ struct ctl_table *table = sd_alloc_ctl_entry(14);
if (table == NULL)
return NULL;
@@ -4554,9 +4964,12 @@ sd_alloc_ctl_domain_table(struct sched_domain *sd)
sizeof(int), 0644, proc_dointvec_minmax, false);
set_table_entry(&table[10], "flags", &sd->flags,
sizeof(int), 0644, proc_dointvec_minmax, false);
- set_table_entry(&table[11], "name", sd->name,
+ set_table_entry(&table[11], "max_newidle_lb_cost",
+ &sd->max_newidle_lb_cost,
+ sizeof(long), 0644, proc_doulongvec_minmax, false);
+ set_table_entry(&table[12], "name", sd->name,
CORENAME_MAX_SIZE, 0444, proc_dostring, false);
- /* &table[12] is terminator */
+ /* &table[13] is terminator */
return table;
}
@@ -4722,11 +5135,20 @@ static struct notifier_block migration_notifier = {
.priority = CPU_PRI_MIGRATION,
};
+static void __cpuinit set_cpu_rq_start_time(void)
+{
+ int cpu = smp_processor_id();
+ struct rq *rq = cpu_rq(cpu);
+ rq->age_stamp = sched_clock_cpu(cpu);
+}
+
static int sched_cpu_active(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
switch (action & ~CPU_TASKS_FROZEN) {
case CPU_STARTING:
+ set_cpu_rq_start_time();
+ return NOTIFY_OK;
case CPU_DOWN_FAILED:
set_cpu_active((long)hcpu, true);
return NOTIFY_OK;
@@ -4738,13 +5160,31 @@ 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;
+
switch (action & ~CPU_TASKS_FROZEN) {
case CPU_DOWN_PREPARE:
- set_cpu_active((long)hcpu, false);
+ set_cpu_active(cpu, false);
+
+ /* explicitly allow suspend */
+ if (!(action & CPU_TASKS_FROZEN)) {
+ struct dl_bw *dl_b = dl_bw_of(cpu);
+ bool overflow;
+ int cpus;
+
+ 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);
+
+ if (overflow)
+ return notifier_from_errno(-EBUSY);
+ }
return NOTIFY_OK;
- default:
- return NOTIFY_DONE;
}
+
+ return NOTIFY_DONE;
}
static int __init migration_init(void)
@@ -4827,14 +5267,13 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
}
/*
- * Even though we initialize ->power to something semi-sane,
- * we leave power_orig unset. This allows us to detect if
+ * 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->sgp->power_orig) {
+ if (!group->sgc->capacity_orig) {
printk(KERN_CONT "\n");
- printk(KERN_ERR "ERROR: domain->cpu_power not "
- "set\n");
+ printk(KERN_ERR "ERROR: domain->cpu_capacity not set\n");
break;
}
@@ -4856,9 +5295,9 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level,
cpulist_scnprintf(str, sizeof(str), sched_group_cpus(group));
printk(KERN_CONT " %s", str);
- if (group->sgp->power != SCHED_POWER_SCALE) {
- printk(KERN_CONT " (cpu_power = %d)",
- group->sgp->power);
+ if (group->sgc->capacity != SCHED_CAPACITY_SCALE) {
+ printk(KERN_CONT " (cpu_capacity = %d)",
+ group->sgc->capacity);
}
group = group->next;
@@ -4916,8 +5355,9 @@ static int sd_degenerate(struct sched_domain *sd)
SD_BALANCE_NEWIDLE |
SD_BALANCE_FORK |
SD_BALANCE_EXEC |
- SD_SHARE_CPUPOWER |
- SD_SHARE_PKG_RESOURCES)) {
+ SD_SHARE_CPUCAPACITY |
+ SD_SHARE_PKG_RESOURCES |
+ SD_SHARE_POWERDOMAIN)) {
if (sd->groups != sd->groups->next)
return 0;
}
@@ -4946,9 +5386,10 @@ sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent)
SD_BALANCE_NEWIDLE |
SD_BALANCE_FORK |
SD_BALANCE_EXEC |
- SD_SHARE_CPUPOWER |
+ SD_SHARE_CPUCAPACITY |
SD_SHARE_PKG_RESOURCES |
- SD_PREFER_SIBLING);
+ SD_PREFER_SIBLING |
+ SD_SHARE_POWERDOMAIN);
if (nr_node_ids == 1)
pflags &= ~SD_SERIALIZE;
}
@@ -4963,6 +5404,8 @@ static void free_rootdomain(struct rcu_head *rcu)
struct root_domain *rd = container_of(rcu, struct root_domain, rcu);
cpupri_cleanup(&rd->cpupri);
+ cpudl_cleanup(&rd->cpudl);
+ free_cpumask_var(rd->dlo_mask);
free_cpumask_var(rd->rto_mask);
free_cpumask_var(rd->online);
free_cpumask_var(rd->span);
@@ -4985,7 +5428,7 @@ static void rq_attach_root(struct rq *rq, struct root_domain *rd)
cpumask_clear_cpu(rq->cpu, old_rd->span);
/*
- * If we dont want to free the old_rt yet then
+ * If we dont want to free the old_rd yet then
* set old_rd to NULL to skip the freeing later
* in this function:
*/
@@ -5014,8 +5457,14 @@ static int init_rootdomain(struct root_domain *rd)
goto out;
if (!alloc_cpumask_var(&rd->online, GFP_KERNEL))
goto free_span;
- if (!alloc_cpumask_var(&rd->rto_mask, GFP_KERNEL))
+ if (!alloc_cpumask_var(&rd->dlo_mask, GFP_KERNEL))
goto free_online;
+ if (!alloc_cpumask_var(&rd->rto_mask, GFP_KERNEL))
+ goto free_dlo_mask;
+
+ init_dl_bw(&rd->dl_bw);
+ if (cpudl_init(&rd->cpudl) != 0)
+ goto free_dlo_mask;
if (cpupri_init(&rd->cpupri) != 0)
goto free_rto_mask;
@@ -5023,6 +5472,8 @@ static int init_rootdomain(struct root_domain *rd)
free_rto_mask:
free_cpumask_var(rd->rto_mask);
+free_dlo_mask:
+ free_cpumask_var(rd->dlo_mask);
free_online:
free_cpumask_var(rd->online);
free_span:
@@ -5060,7 +5511,7 @@ static struct root_domain *alloc_rootdomain(void)
return rd;
}
-static void free_sched_groups(struct sched_group *sg, int free_sgp)
+static void free_sched_groups(struct sched_group *sg, int free_sgc)
{
struct sched_group *tmp, *first;
@@ -5071,8 +5522,8 @@ static void free_sched_groups(struct sched_group *sg, int free_sgp)
do {
tmp = sg->next;
- if (free_sgp && atomic_dec_and_test(&sg->sgp->ref))
- kfree(sg->sgp);
+ if (free_sgc && atomic_dec_and_test(&sg->sgc->ref))
+ kfree(sg->sgc);
kfree(sg);
sg = tmp;
@@ -5090,7 +5541,7 @@ static void free_sched_domain(struct rcu_head *rcu)
if (sd->flags & SD_OVERLAP) {
free_sched_groups(sd->groups, 1);
} else if (atomic_dec_and_test(&sd->groups->ref)) {
- kfree(sd->groups->sgp);
+ kfree(sd->groups->sgc);
kfree(sd->groups);
}
kfree(sd);
@@ -5119,10 +5570,14 @@ static void destroy_sched_domains(struct sched_domain *sd, int cpu)
DEFINE_PER_CPU(struct sched_domain *, sd_llc);
DEFINE_PER_CPU(int, sd_llc_size);
DEFINE_PER_CPU(int, sd_llc_id);
+DEFINE_PER_CPU(struct sched_domain *, sd_numa);
+DEFINE_PER_CPU(struct sched_domain *, sd_busy);
+DEFINE_PER_CPU(struct sched_domain *, sd_asym);
static void update_top_cache_domain(int cpu)
{
struct sched_domain *sd;
+ struct sched_domain *busy_sd = NULL;
int id = cpu;
int size = 1;
@@ -5130,11 +5585,19 @@ static void update_top_cache_domain(int cpu)
if (sd) {
id = cpumask_first(sched_domain_span(sd));
size = cpumask_weight(sched_domain_span(sd));
+ busy_sd = sd->parent; /* sd_busy */
}
+ rcu_assign_pointer(per_cpu(sd_busy, cpu), busy_sd);
rcu_assign_pointer(per_cpu(sd_llc, cpu), sd);
per_cpu(sd_llc_size, cpu) = size;
per_cpu(sd_llc_id, cpu) = id;
+
+ sd = lowest_flag_domain(cpu, SD_NUMA);
+ rcu_assign_pointer(per_cpu(sd_numa, cpu), sd);
+
+ sd = highest_flag_domain(cpu, SD_ASYM_PACKING);
+ rcu_assign_pointer(per_cpu(sd_asym, cpu), sd);
}
/*
@@ -5200,17 +5663,6 @@ static int __init isolated_cpu_setup(char *str)
__setup("isolcpus=", isolated_cpu_setup);
-static const struct cpumask *cpu_cpu_mask(int cpu)
-{
- return cpumask_of_node(cpu_to_node(cpu));
-}
-
-struct sd_data {
- struct sched_domain **__percpu sd;
- struct sched_group **__percpu sg;
- struct sched_group_power **__percpu sgp;
-};
-
struct s_data {
struct sched_domain ** __percpu sd;
struct root_domain *rd;
@@ -5223,21 +5675,6 @@ enum s_alloc {
sa_none,
};
-struct sched_domain_topology_level;
-
-typedef struct sched_domain *(*sched_domain_init_f)(struct sched_domain_topology_level *tl, int cpu);
-typedef const struct cpumask *(*sched_domain_mask_f)(int cpu);
-
-#define SDTL_OVERLAP 0x01
-
-struct sched_domain_topology_level {
- sched_domain_init_f init;
- sched_domain_mask_f mask;
- int flags;
- int numa_level;
- struct sd_data data;
-};
-
/*
* Build an iteration mask that can exclude certain CPUs from the upwards
* domain traversal.
@@ -5315,16 +5752,17 @@ build_overlap_sched_groups(struct sched_domain *sd, int cpu)
cpumask_or(covered, covered, sg_span);
- sg->sgp = *per_cpu_ptr(sdd->sgp, i);
- if (atomic_inc_return(&sg->sgp->ref) == 1)
+ sg->sgc = *per_cpu_ptr(sdd->sgc, i);
+ if (atomic_inc_return(&sg->sgc->ref) == 1)
build_group_mask(sd, sg);
/*
- * Initialize sgp->power such that even if we mess up the
+ * Initialize sgc->capacity such that even if we mess up the
* domains and no possible iteration will get us here, we won't
* die on a /0 trap.
*/
- sg->sgp->power = SCHED_POWER_SCALE * cpumask_weight(sg_span);
+ 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
@@ -5362,8 +5800,8 @@ static int get_group(int cpu, struct sd_data *sdd, struct sched_group **sg)
if (sg) {
*sg = *per_cpu_ptr(sdd->sg, cpu);
- (*sg)->sgp = *per_cpu_ptr(sdd->sgp, cpu);
- atomic_set(&(*sg)->sgp->ref, 1); /* for claim_allocations */
+ (*sg)->sgc = *per_cpu_ptr(sdd->sgc, cpu);
+ atomic_set(&(*sg)->sgc->ref, 1); /* for claim_allocations */
}
return cpu;
@@ -5372,7 +5810,7 @@ static int get_group(int cpu, struct sd_data *sdd, struct sched_group **sg)
/*
* build_sched_groups will build a circular linked list of the groups
* covered by the given span, and will set each group's ->cpumask correctly,
- * and ->cpu_power to 0.
+ * and ->cpu_capacity to 0.
*
* Assumes the sched_domain tree is fully constructed
*/
@@ -5404,8 +5842,6 @@ build_sched_groups(struct sched_domain *sd, int cpu)
continue;
group = get_group(i, sdd, &sg);
- cpumask_clear(sched_group_cpus(sg));
- sg->sgp->power = 0;
cpumask_setall(sched_group_mask(sg));
for_each_cpu(j, span) {
@@ -5428,16 +5864,16 @@ build_sched_groups(struct sched_domain *sd, int cpu)
}
/*
- * Initialize sched groups cpu_power.
+ * Initialize sched groups cpu_capacity.
*
- * cpu_power indicates the capacity of sched group, which is used while
+ * cpu_capacity indicates the capacity of sched group, which is used while
* distributing the load between different sched groups in a sched domain.
- * Typically cpu_power for all the groups in a sched domain will be same unless
- * there are asymmetries in the topology. If there are asymmetries, group
- * having more cpu_power will pickup more load compared to the group having
- * less cpu_power.
+ * Typically cpu_capacity for all the groups in a sched domain will be same
+ * unless there are asymmetries in the topology. If there are asymmetries,
+ * group having more cpu_capacity will pickup more load compared to the
+ * group having less cpu_capacity.
*/
-static void init_sched_groups_power(int cpu, struct sched_domain *sd)
+static void init_sched_groups_capacity(int cpu, struct sched_domain *sd)
{
struct sched_group *sg = sd->groups;
@@ -5451,13 +5887,8 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd)
if (cpu != group_balance_cpu(sg))
return;
- update_group_power(sd, cpu);
- atomic_set(&sg->sgp->nr_busy_cpus, sg->group_weight);
-}
-
-int __weak arch_sd_sibling_asym_packing(void)
-{
- return 0*SD_ASYM_PACKING;
+ update_group_capacity(sd, cpu);
+ atomic_set(&sg->sgc->nr_busy_cpus, sg->group_weight);
}
/*
@@ -5465,34 +5896,6 @@ int __weak arch_sd_sibling_asym_packing(void)
* Non-inlined to reduce accumulated stack pressure in build_sched_domains()
*/
-#ifdef CONFIG_SCHED_DEBUG
-# define SD_INIT_NAME(sd, type) sd->name = #type
-#else
-# define SD_INIT_NAME(sd, type) do { } while (0)
-#endif
-
-#define SD_INIT_FUNC(type) \
-static noinline struct sched_domain * \
-sd_init_##type(struct sched_domain_topology_level *tl, int cpu) \
-{ \
- struct sched_domain *sd = *per_cpu_ptr(tl->data.sd, cpu); \
- *sd = SD_##type##_INIT; \
- SD_INIT_NAME(sd, type); \
- sd->private = &tl->data; \
- return sd; \
-}
-
-SD_INIT_FUNC(CPU)
-#ifdef CONFIG_SCHED_SMT
- SD_INIT_FUNC(SIBLING)
-#endif
-#ifdef CONFIG_SCHED_MC
- SD_INIT_FUNC(MC)
-#endif
-#ifdef CONFIG_SCHED_BOOK
- SD_INIT_FUNC(BOOK)
-#endif
-
static int default_relax_domain_level = -1;
int sched_domain_level_max;
@@ -5576,100 +5979,158 @@ static void claim_allocations(int cpu, struct sched_domain *sd)
if (atomic_read(&(*per_cpu_ptr(sdd->sg, cpu))->ref))
*per_cpu_ptr(sdd->sg, cpu) = NULL;
- if (atomic_read(&(*per_cpu_ptr(sdd->sgp, cpu))->ref))
- *per_cpu_ptr(sdd->sgp, cpu) = NULL;
-}
-
-#ifdef CONFIG_SCHED_SMT
-static const struct cpumask *cpu_smt_mask(int cpu)
-{
- return topology_thread_cpumask(cpu);
+ if (atomic_read(&(*per_cpu_ptr(sdd->sgc, cpu))->ref))
+ *per_cpu_ptr(sdd->sgc, cpu) = NULL;
}
-#endif
-
-/*
- * Topology list, bottom-up.
- */
-static struct sched_domain_topology_level default_topology[] = {
-#ifdef CONFIG_SCHED_SMT
- { sd_init_SIBLING, cpu_smt_mask, },
-#endif
-#ifdef CONFIG_SCHED_MC
- { sd_init_MC, cpu_coregroup_mask, },
-#endif
-#ifdef CONFIG_SCHED_BOOK
- { sd_init_BOOK, cpu_book_mask, },
-#endif
- { sd_init_CPU, cpu_cpu_mask, },
- { NULL, },
-};
-
-static struct sched_domain_topology_level *sched_domain_topology = default_topology;
-
-#define for_each_sd_topology(tl) \
- for (tl = sched_domain_topology; tl->init; tl++)
#ifdef CONFIG_NUMA
-
static int sched_domains_numa_levels;
static int *sched_domains_numa_distance;
static struct cpumask ***sched_domains_numa_masks;
static int sched_domains_curr_level;
+#endif
-static inline int sd_local_flags(int level)
-{
- if (sched_domains_numa_distance[level] > RECLAIM_DISTANCE)
- return 0;
-
- return SD_BALANCE_EXEC | SD_BALANCE_FORK | SD_WAKE_AFFINE;
-}
+/*
+ * SD_flags allowed in topology descriptions.
+ *
+ * SD_SHARE_CPUCAPACITY - describes SMT topologies
+ * SD_SHARE_PKG_RESOURCES - describes shared caches
+ * SD_NUMA - describes NUMA topologies
+ * SD_SHARE_POWERDOMAIN - describes shared power domain
+ *
+ * Odd one out:
+ * SD_ASYM_PACKING - describes SMT quirks
+ */
+#define TOPOLOGY_SD_FLAGS \
+ (SD_SHARE_CPUCAPACITY | \
+ SD_SHARE_PKG_RESOURCES | \
+ SD_NUMA | \
+ SD_ASYM_PACKING | \
+ SD_SHARE_POWERDOMAIN)
static struct sched_domain *
-sd_numa_init(struct sched_domain_topology_level *tl, int cpu)
+sd_init(struct sched_domain_topology_level *tl, int cpu)
{
struct sched_domain *sd = *per_cpu_ptr(tl->data.sd, cpu);
- int level = tl->numa_level;
- int sd_weight = cpumask_weight(
- sched_domains_numa_masks[level][cpu_to_node(cpu)]);
+ int sd_weight, sd_flags = 0;
+
+#ifdef CONFIG_NUMA
+ /*
+ * Ugly hack to pass state to sd_numa_mask()...
+ */
+ sched_domains_curr_level = tl->numa_level;
+#endif
+
+ sd_weight = cpumask_weight(tl->mask(cpu));
+
+ if (tl->sd_flags)
+ sd_flags = (*tl->sd_flags)();
+ if (WARN_ONCE(sd_flags & ~TOPOLOGY_SD_FLAGS,
+ "wrong sd_flags in topology description\n"))
+ sd_flags &= ~TOPOLOGY_SD_FLAGS;
*sd = (struct sched_domain){
.min_interval = sd_weight,
.max_interval = 2*sd_weight,
.busy_factor = 32,
.imbalance_pct = 125,
- .cache_nice_tries = 2,
- .busy_idx = 3,
- .idle_idx = 2,
+
+ .cache_nice_tries = 0,
+ .busy_idx = 0,
+ .idle_idx = 0,
.newidle_idx = 0,
.wake_idx = 0,
.forkexec_idx = 0,
.flags = 1*SD_LOAD_BALANCE
| 1*SD_BALANCE_NEWIDLE
- | 0*SD_BALANCE_EXEC
- | 0*SD_BALANCE_FORK
+ | 1*SD_BALANCE_EXEC
+ | 1*SD_BALANCE_FORK
| 0*SD_BALANCE_WAKE
- | 0*SD_WAKE_AFFINE
- | 0*SD_SHARE_CPUPOWER
+ | 1*SD_WAKE_AFFINE
+ | 0*SD_SHARE_CPUCAPACITY
| 0*SD_SHARE_PKG_RESOURCES
- | 1*SD_SERIALIZE
+ | 0*SD_SERIALIZE
| 0*SD_PREFER_SIBLING
- | sd_local_flags(level)
+ | 0*SD_NUMA
+ | sd_flags
,
+
.last_balance = jiffies,
.balance_interval = sd_weight,
+ .smt_gain = 0,
+ .max_newidle_lb_cost = 0,
+ .next_decay_max_lb_cost = jiffies,
+#ifdef CONFIG_SCHED_DEBUG
+ .name = tl->name,
+#endif
};
- SD_INIT_NAME(sd, NUMA);
- sd->private = &tl->data;
/*
- * Ugly hack to pass state to sd_numa_mask()...
+ * Convert topological properties into behaviour.
*/
- sched_domains_curr_level = tl->numa_level;
+
+ if (sd->flags & SD_SHARE_CPUCAPACITY) {
+ sd->imbalance_pct = 110;
+ sd->smt_gain = 1178; /* ~15% */
+
+ } else if (sd->flags & SD_SHARE_PKG_RESOURCES) {
+ sd->imbalance_pct = 117;
+ sd->cache_nice_tries = 1;
+ sd->busy_idx = 2;
+
+#ifdef CONFIG_NUMA
+ } else if (sd->flags & SD_NUMA) {
+ sd->cache_nice_tries = 2;
+ sd->busy_idx = 3;
+ sd->idle_idx = 2;
+
+ sd->flags |= SD_SERIALIZE;
+ if (sched_domains_numa_distance[tl->numa_level] > RECLAIM_DISTANCE) {
+ sd->flags &= ~(SD_BALANCE_EXEC |
+ SD_BALANCE_FORK |
+ SD_WAKE_AFFINE);
+ }
+
+#endif
+ } else {
+ sd->flags |= SD_PREFER_SIBLING;
+ sd->cache_nice_tries = 1;
+ sd->busy_idx = 2;
+ sd->idle_idx = 1;
+ }
+
+ sd->private = &tl->data;
return sd;
}
+/*
+ * Topology list, bottom-up.
+ */
+static struct sched_domain_topology_level default_topology[] = {
+#ifdef CONFIG_SCHED_SMT
+ { cpu_smt_mask, cpu_smt_flags, SD_INIT_NAME(SMT) },
+#endif
+#ifdef CONFIG_SCHED_MC
+ { cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) },
+#endif
+ { cpu_cpu_mask, SD_INIT_NAME(DIE) },
+ { NULL, },
+};
+
+struct sched_domain_topology_level *sched_domain_topology = default_topology;
+
+#define for_each_sd_topology(tl) \
+ for (tl = sched_domain_topology; tl->mask; tl++)
+
+void set_sched_topology(struct sched_domain_topology_level *tl)
+{
+ sched_domain_topology = tl;
+}
+
+#ifdef CONFIG_NUMA
+
static const struct cpumask *sd_numa_mask(int cpu)
{
return sched_domains_numa_masks[sched_domains_curr_level][cpu_to_node(cpu)];
@@ -5813,7 +6274,10 @@ static void sched_init_numa(void)
}
}
- tl = kzalloc((ARRAY_SIZE(default_topology) + level) *
+ /* Compute default topology size */
+ for (i = 0; sched_domain_topology[i].mask; i++);
+
+ tl = kzalloc((i + level + 1) *
sizeof(struct sched_domain_topology_level), GFP_KERNEL);
if (!tl)
return;
@@ -5821,18 +6285,19 @@ static void sched_init_numa(void)
/*
* Copy the default topology bits..
*/
- for (i = 0; default_topology[i].init; i++)
- tl[i] = default_topology[i];
+ for (i = 0; sched_domain_topology[i].mask; i++)
+ tl[i] = sched_domain_topology[i];
/*
* .. and append 'j' levels of NUMA goodness.
*/
for (j = 0; j < level; i++, j++) {
tl[i] = (struct sched_domain_topology_level){
- .init = sd_numa_init,
.mask = sd_numa_mask,
+ .sd_flags = cpu_numa_flags,
.flags = SDTL_OVERLAP,
.numa_level = j,
+ SD_INIT_NAME(NUMA)
};
}
@@ -5917,14 +6382,14 @@ static int __sdt_alloc(const struct cpumask *cpu_map)
if (!sdd->sg)
return -ENOMEM;
- sdd->sgp = alloc_percpu(struct sched_group_power *);
- if (!sdd->sgp)
+ sdd->sgc = alloc_percpu(struct sched_group_capacity *);
+ if (!sdd->sgc)
return -ENOMEM;
for_each_cpu(j, cpu_map) {
struct sched_domain *sd;
struct sched_group *sg;
- struct sched_group_power *sgp;
+ struct sched_group_capacity *sgc;
sd = kzalloc_node(sizeof(struct sched_domain) + cpumask_size(),
GFP_KERNEL, cpu_to_node(j));
@@ -5942,12 +6407,12 @@ static int __sdt_alloc(const struct cpumask *cpu_map)
*per_cpu_ptr(sdd->sg, j) = sg;
- sgp = kzalloc_node(sizeof(struct sched_group_power) + cpumask_size(),
+ sgc = kzalloc_node(sizeof(struct sched_group_capacity) + cpumask_size(),
GFP_KERNEL, cpu_to_node(j));
- if (!sgp)
+ if (!sgc)
return -ENOMEM;
- *per_cpu_ptr(sdd->sgp, j) = sgp;
+ *per_cpu_ptr(sdd->sgc, j) = sgc;
}
}
@@ -5974,15 +6439,15 @@ static void __sdt_free(const struct cpumask *cpu_map)
if (sdd->sg)
kfree(*per_cpu_ptr(sdd->sg, j));
- if (sdd->sgp)
- kfree(*per_cpu_ptr(sdd->sgp, j));
+ if (sdd->sgc)
+ kfree(*per_cpu_ptr(sdd->sgc, j));
}
free_percpu(sdd->sd);
sdd->sd = NULL;
free_percpu(sdd->sg);
sdd->sg = NULL;
- free_percpu(sdd->sgp);
- sdd->sgp = NULL;
+ free_percpu(sdd->sgc);
+ sdd->sgc = NULL;
}
}
@@ -5990,7 +6455,7 @@ struct sched_domain *build_sched_domain(struct sched_domain_topology_level *tl,
const struct cpumask *cpu_map, struct sched_domain_attr *attr,
struct sched_domain *child, int cpu)
{
- struct sched_domain *sd = tl->init(tl, cpu);
+ struct sched_domain *sd = sd_init(tl, cpu);
if (!sd)
return child;
@@ -6052,14 +6517,14 @@ static int build_sched_domains(const struct cpumask *cpu_map,
}
}
- /* Calculate CPU power for physical packages and nodes */
+ /* Calculate CPU capacity for physical packages and nodes */
for (i = nr_cpumask_bits-1; i >= 0; i--) {
if (!cpumask_test_cpu(i, cpu_map))
continue;
for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) {
claim_allocations(i, sd);
- init_sched_groups_power(i, sd);
+ init_sched_groups_capacity(i, sd);
}
}
@@ -6094,7 +6559,7 @@ static cpumask_var_t fallback_doms;
* cpu core maps. It is supposed to return 1 if the topology changed
* or 0 if it stayed the same.
*/
-int __attribute__((weak)) arch_update_cpu_topology(void)
+int __weak arch_update_cpu_topology(void)
{
return 0;
}
@@ -6335,14 +6800,17 @@ void __init sched_init_smp(void)
sched_init_numa();
- get_online_cpus();
+ /*
+ * There's no userspace yet to cause hotplug operations; hence all the
+ * cpu masks are stable and all blatant races in the below code cannot
+ * happen.
+ */
mutex_lock(&sched_domains_mutex);
init_sched_domains(cpu_active_mask);
cpumask_andnot(non_isolated_cpus, cpu_possible_mask, cpu_isolated_map);
if (cpumask_empty(non_isolated_cpus))
cpumask_set_cpu(smp_processor_id(), non_isolated_cpus);
mutex_unlock(&sched_domains_mutex);
- put_online_cpus();
hotcpu_notifier(sched_domains_numa_masks_update, CPU_PRI_SCHED_ACTIVE);
hotcpu_notifier(cpuset_cpu_active, CPU_PRI_CPUSET_ACTIVE);
@@ -6357,6 +6825,7 @@ void __init sched_init_smp(void)
free_cpumask_var(non_isolated_cpus);
init_sched_rt_class();
+ init_sched_dl_class();
}
#else
void __init sched_init_smp(void)
@@ -6426,13 +6895,15 @@ void __init sched_init(void)
#endif /* CONFIG_CPUMASK_OFFSTACK */
}
+ init_rt_bandwidth(&def_rt_bandwidth,
+ global_rt_period(), global_rt_runtime());
+ init_dl_bandwidth(&def_dl_bandwidth,
+ global_rt_period(), global_rt_runtime());
+
#ifdef CONFIG_SMP
init_defrootdomain();
#endif
- init_rt_bandwidth(&def_rt_bandwidth,
- global_rt_period(), global_rt_runtime());
-
#ifdef CONFIG_RT_GROUP_SCHED
init_rt_bandwidth(&root_task_group.rt_bandwidth,
global_rt_period(), global_rt_runtime());
@@ -6456,6 +6927,7 @@ void __init sched_init(void)
rq->calc_load_update = jiffies + LOAD_FREQ;
init_cfs_rq(&rq->cfs);
init_rt_rq(&rq->rt, rq);
+ init_dl_rq(&rq->dl, rq);
#ifdef CONFIG_FAIR_GROUP_SCHED
root_task_group.shares = ROOT_TASK_GROUP_LOAD;
INIT_LIST_HEAD(&rq->leaf_cfs_rq_list);
@@ -6484,7 +6956,6 @@ void __init sched_init(void)
rq->rt.rt_runtime = def_rt_bandwidth.rt_runtime;
#ifdef CONFIG_RT_GROUP_SCHED
- INIT_LIST_HEAD(&rq->leaf_rt_rq_list);
init_tg_rt_entry(&root_task_group, &rq->rt, NULL, i, NULL);
#endif
@@ -6496,7 +6967,7 @@ void __init sched_init(void)
#ifdef CONFIG_SMP
rq->sd = NULL;
rq->rd = NULL;
- rq->cpu_power = SCHED_POWER_SCALE;
+ rq->cpu_capacity = SCHED_CAPACITY_SCALE;
rq->post_schedule = 0;
rq->active_balance = 0;
rq->next_balance = jiffies;
@@ -6505,6 +6976,7 @@ void __init sched_init(void)
rq->online = 0;
rq->idle_stamp = 0;
rq->avg_idle = 2*sysctl_sched_migration_cost;
+ rq->max_idle_balance_cost = sysctl_sched_migration_cost;
INIT_LIST_HEAD(&rq->cfs_tasks);
@@ -6526,10 +6998,6 @@ void __init sched_init(void)
INIT_HLIST_HEAD(&init_task.preempt_notifiers);
#endif
-#ifdef CONFIG_RT_MUTEXES
- plist_head_init(&init_task.pi_waiters);
-#endif
-
/*
* The boot idle thread does lazy MMU switching as well:
*/
@@ -6557,6 +7025,7 @@ void __init sched_init(void)
if (cpu_isolated_map == NULL)
zalloc_cpumask_var(&cpu_isolated_map, GFP_NOWAIT);
idle_thread_set_boot_cpu();
+ set_cpu_rq_start_time();
#endif
init_sched_fair_class();
@@ -6576,7 +7045,8 @@ void __might_sleep(const char *file, int line, int preempt_offset)
static unsigned long prev_jiffy; /* ratelimiting */
rcu_sleep_check(); /* WARN_ON_ONCE() by default, no rate limit reqd. */
- if ((preempt_count_equals(preempt_offset) && !irqs_disabled()) ||
+ if ((preempt_count_equals(preempt_offset) && !irqs_disabled() &&
+ !is_idle_task(current)) ||
system_state != SYSTEM_RUNNING || oops_in_progress)
return;
if (time_before(jiffies, prev_jiffy + HZ) && prev_jiffy)
@@ -6594,6 +7064,13 @@ void __might_sleep(const char *file, int line, int preempt_offset)
debug_show_held_locks(current);
if (irqs_disabled())
print_irqtrace_events(current);
+#ifdef CONFIG_DEBUG_PREEMPT
+ if (!preempt_count_equals(preempt_offset)) {
+ pr_err("Preemption disabled at:");
+ print_ip_sym(current->preempt_disable_ip);
+ pr_cont("\n");
+ }
+#endif
dump_stack();
}
EXPORT_SYMBOL(__might_sleep);
@@ -6603,13 +7080,16 @@ EXPORT_SYMBOL(__might_sleep);
static void normalize_task(struct rq *rq, struct task_struct *p)
{
const struct sched_class *prev_class = p->sched_class;
+ struct sched_attr attr = {
+ .sched_policy = SCHED_NORMAL,
+ };
int old_prio = p->prio;
int on_rq;
on_rq = p->on_rq;
if (on_rq)
dequeue_task(rq, p, 0);
- __setscheduler(rq, p, SCHED_NORMAL, 0);
+ __setscheduler(rq, p, &attr);
if (on_rq) {
enqueue_task(rq, p, 0);
resched_task(rq->curr);
@@ -6639,12 +7119,12 @@ void normalize_rt_tasks(void)
p->se.statistics.block_start = 0;
#endif
- if (!rt_task(p)) {
+ if (!dl_task(p) && !rt_task(p)) {
/*
* Renice negative nice level userspace
* tasks back to 0:
*/
- if (TASK_NICE(p) < 0 && p->mm)
+ if (task_nice(p) < 0 && p->mm)
set_user_nice(p, 0);
continue;
}
@@ -6812,7 +7292,7 @@ void sched_move_task(struct task_struct *tsk)
if (unlikely(running))
tsk->sched_class->put_prev_task(rq, tsk);
- tg = container_of(task_css_check(tsk, cpu_cgroup_subsys_id,
+ tg = container_of(task_css_check(tsk, cpu_cgrp_id,
lockdep_is_held(&tsk->sighand->siglock)),
struct task_group, css);
tg = autogroup_task_group(tsk, tg);
@@ -6834,16 +7314,6 @@ void sched_move_task(struct task_struct *tsk)
}
#endif /* CONFIG_CGROUP_SCHED */
-#if defined(CONFIG_RT_GROUP_SCHED) || defined(CONFIG_CFS_BANDWIDTH)
-static unsigned long to_ratio(u64 period, u64 runtime)
-{
- if (runtime == RUNTIME_INF)
- return 1ULL << 20;
-
- return div64_u64(runtime << 20, period);
-}
-#endif
-
#ifdef CONFIG_RT_GROUP_SCHED
/*
* Ensure that the real time constraints are schedulable.
@@ -7017,24 +7487,13 @@ static long sched_group_rt_period(struct task_group *tg)
do_div(rt_period_us, NSEC_PER_USEC);
return rt_period_us;
}
+#endif /* CONFIG_RT_GROUP_SCHED */
+#ifdef CONFIG_RT_GROUP_SCHED
static int sched_rt_global_constraints(void)
{
- u64 runtime, period;
int ret = 0;
- if (sysctl_sched_rt_period <= 0)
- return -EINVAL;
-
- runtime = global_rt_runtime();
- period = global_rt_period();
-
- /*
- * Sanity check on the sysctl variables.
- */
- if (runtime > period && runtime != RUNTIME_INF)
- return -EINVAL;
-
mutex_lock(&rt_constraints_mutex);
read_lock(&tasklist_lock);
ret = __rt_schedulable(NULL, 0, 0);
@@ -7057,17 +7516,7 @@ static int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk)
static int sched_rt_global_constraints(void)
{
unsigned long flags;
- int i;
-
- if (sysctl_sched_rt_period <= 0)
- return -EINVAL;
-
- /*
- * There's always some RT tasks in the root group
- * -- migration, kstopmachine etc..
- */
- if (sysctl_sched_rt_runtime == 0)
- return -EBUSY;
+ int i, ret = 0;
raw_spin_lock_irqsave(&def_rt_bandwidth.rt_runtime_lock, flags);
for_each_possible_cpu(i) {
@@ -7079,36 +7528,91 @@ static int sched_rt_global_constraints(void)
}
raw_spin_unlock_irqrestore(&def_rt_bandwidth.rt_runtime_lock, flags);
- return 0;
+ return ret;
}
#endif /* CONFIG_RT_GROUP_SCHED */
-int sched_rr_handler(struct ctl_table *table, int write,
- void __user *buffer, size_t *lenp,
- loff_t *ppos)
+static int sched_dl_global_constraints(void)
{
- int ret;
- static DEFINE_MUTEX(mutex);
+ u64 runtime = global_rt_runtime();
+ u64 period = global_rt_period();
+ u64 new_bw = to_ratio(period, runtime);
+ int cpu, ret = 0;
+ unsigned long flags;
- mutex_lock(&mutex);
- ret = proc_dointvec(table, write, buffer, lenp, ppos);
- /* make sure that internally we keep jiffies */
- /* also, writing zero resets timeslice to default */
- if (!ret && write) {
- sched_rr_timeslice = sched_rr_timeslice <= 0 ?
- RR_TIMESLICE : msecs_to_jiffies(sched_rr_timeslice);
+ /*
+ * 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) {
+ struct dl_bw *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);
+
+ if (ret)
+ break;
}
- mutex_unlock(&mutex);
+
return ret;
}
+static void sched_dl_do_global(void)
+{
+ u64 new_bw = -1;
+ 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) {
+ struct dl_bw *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);
+ }
+}
+
+static int sched_rt_global_validate(void)
+{
+ if (sysctl_sched_rt_period <= 0)
+ return -EINVAL;
+
+ if ((sysctl_sched_rt_runtime != RUNTIME_INF) &&
+ (sysctl_sched_rt_runtime > sysctl_sched_rt_period))
+ return -EINVAL;
+
+ return 0;
+}
+
+static void sched_rt_do_global(void)
+{
+ def_rt_bandwidth.rt_runtime = global_rt_runtime();
+ def_rt_bandwidth.rt_period = ns_to_ktime(global_rt_period());
+}
+
int sched_rt_handler(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp,
loff_t *ppos)
{
- int ret;
int old_period, old_runtime;
static DEFINE_MUTEX(mutex);
+ int ret;
mutex_lock(&mutex);
old_period = sysctl_sched_rt_period;
@@ -7117,21 +7621,50 @@ int sched_rt_handler(struct ctl_table *table, int write,
ret = proc_dointvec(table, write, buffer, lenp, ppos);
if (!ret && write) {
+ ret = sched_rt_global_validate();
+ if (ret)
+ goto undo;
+
ret = sched_rt_global_constraints();
- if (ret) {
- sysctl_sched_rt_period = old_period;
- sysctl_sched_rt_runtime = old_runtime;
- } else {
- def_rt_bandwidth.rt_runtime = global_rt_runtime();
- def_rt_bandwidth.rt_period =
- ns_to_ktime(global_rt_period());
- }
+ if (ret)
+ goto undo;
+
+ ret = sched_dl_global_constraints();
+ if (ret)
+ goto undo;
+
+ sched_rt_do_global();
+ sched_dl_do_global();
+ }
+ if (0) {
+undo:
+ sysctl_sched_rt_period = old_period;
+ sysctl_sched_rt_runtime = old_runtime;
}
mutex_unlock(&mutex);
return ret;
}
+int sched_rr_handler(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp,
+ loff_t *ppos)
+{
+ int ret;
+ static DEFINE_MUTEX(mutex);
+
+ mutex_lock(&mutex);
+ ret = proc_dointvec(table, write, buffer, lenp, ppos);
+ /* make sure that internally we keep jiffies */
+ /* also, writing zero resets timeslice to default */
+ if (!ret && write) {
+ sched_rr_timeslice = sched_rr_timeslice <= 0 ?
+ RR_TIMESLICE : msecs_to_jiffies(sched_rr_timeslice);
+ }
+ mutex_unlock(&mutex);
+ return ret;
+}
+
#ifdef CONFIG_CGROUP_SCHED
static inline struct task_group *css_tg(struct cgroup_subsys_state *css)
@@ -7160,7 +7693,7 @@ cpu_cgroup_css_alloc(struct cgroup_subsys_state *parent_css)
static int cpu_cgroup_css_online(struct cgroup_subsys_state *css)
{
struct task_group *tg = css_tg(css);
- struct task_group *parent = css_tg(css_parent(css));
+ struct task_group *parent = css_tg(css->parent);
if (parent)
sched_online_group(tg, parent);
@@ -7186,7 +7719,7 @@ static int cpu_cgroup_can_attach(struct cgroup_subsys_state *css,
{
struct task_struct *task;
- cgroup_taskset_for_each(task, css, tset) {
+ cgroup_taskset_for_each(task, tset) {
#ifdef CONFIG_RT_GROUP_SCHED
if (!sched_rt_can_attach(css_tg(css), task))
return -EINVAL;
@@ -7204,7 +7737,7 @@ static void cpu_cgroup_attach(struct cgroup_subsys_state *css,
{
struct task_struct *task;
- cgroup_taskset_for_each(task, css, tset)
+ cgroup_taskset_for_each(task, tset)
sched_move_task(task);
}
@@ -7277,7 +7810,12 @@ static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota)
runtime_enabled = quota != RUNTIME_INF;
runtime_was_enabled = cfs_b->quota != RUNTIME_INF;
- account_cfs_bandwidth_used(runtime_enabled, runtime_was_enabled);
+ /*
+ * If we need to toggle cfs_bandwidth_used, off->on must occur
+ * before making related changes, and on->off must occur afterwards
+ */
+ if (runtime_enabled && !runtime_was_enabled)
+ cfs_bandwidth_usage_inc();
raw_spin_lock_irq(&cfs_b->lock);
cfs_b->period = ns_to_ktime(period);
cfs_b->quota = quota;
@@ -7286,8 +7824,7 @@ static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota)
/* restart the period timer (if active) to handle new period expiry */
if (runtime_enabled && cfs_b->timer_active) {
/* force a reprogram */
- cfs_b->timer_active = 0;
- __start_cfs_bandwidth(cfs_b);
+ __start_cfs_bandwidth(cfs_b, true);
}
raw_spin_unlock_irq(&cfs_b->lock);
@@ -7303,6 +7840,8 @@ static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota)
unthrottle_cfs_rq(cfs_rq);
raw_spin_unlock_irq(&rq->lock);
}
+ if (runtime_was_enabled && !runtime_enabled)
+ cfs_bandwidth_usage_dec();
out_unlock:
mutex_unlock(&cfs_constraints_mutex);
@@ -7457,15 +7996,14 @@ static int __cfs_schedulable(struct task_group *tg, u64 period, u64 quota)
return ret;
}
-static int cpu_stats_show(struct cgroup_subsys_state *css, struct cftype *cft,
- struct cgroup_map_cb *cb)
+static int cpu_stats_show(struct seq_file *sf, void *v)
{
- struct task_group *tg = css_tg(css);
+ struct task_group *tg = css_tg(seq_css(sf));
struct cfs_bandwidth *cfs_b = &tg->cfs_bandwidth;
- cb->fill(cb, "nr_periods", cfs_b->nr_periods);
- cb->fill(cb, "nr_throttled", cfs_b->nr_throttled);
- cb->fill(cb, "throttled_time", cfs_b->throttled_time);
+ seq_printf(sf, "nr_periods %d\n", cfs_b->nr_periods);
+ seq_printf(sf, "nr_throttled %d\n", cfs_b->nr_throttled);
+ seq_printf(sf, "throttled_time %llu\n", cfs_b->throttled_time);
return 0;
}
@@ -7519,7 +8057,7 @@ static struct cftype cpu_files[] = {
},
{
.name = "stat",
- .read_map = cpu_stats_show,
+ .seq_show = cpu_stats_show,
},
#endif
#ifdef CONFIG_RT_GROUP_SCHED
@@ -7537,8 +8075,7 @@ static struct cftype cpu_files[] = {
{ } /* terminate */
};
-struct cgroup_subsys cpu_cgroup_subsys = {
- .name = "cpu",
+struct cgroup_subsys cpu_cgrp_subsys = {
.css_alloc = cpu_cgroup_css_alloc,
.css_free = cpu_cgroup_css_free,
.css_online = cpu_cgroup_css_online,
@@ -7546,7 +8083,6 @@ struct cgroup_subsys cpu_cgroup_subsys = {
.can_attach = cpu_cgroup_can_attach,
.attach = cpu_cgroup_attach,
.exit = cpu_cgroup_exit,
- .subsys_id = cpu_cgroup_subsys_id,
.base_cftypes = cpu_files,
.early_init = 1,
};