1 files changed, 132 insertions, 12 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index d601fb0406ca..ad1962dc0aa2 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -201,7 +201,7 @@ void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime)
         hrtimer_init(&rt_b->rt_period_timer,
                         CLOCK_MONOTONIC, HRTIMER_MODE_REL);
         rt_b->rt_period_timer.function = sched_rt_period_timer;
-        rt_b->rt_period_timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ;
+        rt_b->rt_period_timer.cb_mode = HRTIMER_CB_IRQSAFE_UNLOCKED;
 }
 
 static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
@@ -808,9 +808,9 @@ const_debug unsigned int sysctl_sched_nr_migrate = 32;
 
 /*
  * ratelimit for updating the group shares.
- * default: 0.5ms
+ * default: 0.25ms
  */
-const_debug unsigned int sysctl_sched_shares_ratelimit = 500000;
+unsigned int sysctl_sched_shares_ratelimit = 250000;
 
 /*
  * period over which we measure -rt task cpu usage in us.
@@ -1087,7 +1087,7 @@ hotplug_hrtick(struct notifier_block *nfb, unsigned long action, void *hcpu)
         return NOTIFY_DONE;
 }
 
-static void init_hrtick(void)
+static __init void init_hrtick(void)
 {
         hotcpu_notifier(hotplug_hrtick, 0);
 }
@@ -1119,7 +1119,7 @@ static void init_rq_hrtick(struct rq *rq)
 
         hrtimer_init(&rq->hrtick_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
         rq->hrtick_timer.function = hrtick;
-        rq->hrtick_timer.cb_mode = HRTIMER_CB_IRQSAFE_NO_SOFTIRQ;
+        rq->hrtick_timer.cb_mode = HRTIMER_CB_IRQSAFE_PERCPU;
 }
 #else
 static inline void hrtick_clear(struct rq *rq)
@@ -4179,6 +4179,65 @@ void account_steal_time(struct task_struct *p, cputime_t steal)
 }
 
 /*
+ * Use precise platform statistics if available:
+ */
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+cputime_t task_utime(struct task_struct *p)
+{
+        return p->utime;
+}
+
+cputime_t task_stime(struct task_struct *p)
+{
+        return p->stime;
+}
+#else
+cputime_t task_utime(struct task_struct *p)
+{
+        clock_t utime = cputime_to_clock_t(p->utime),
+                total = utime + cputime_to_clock_t(p->stime);
+        u64 temp;
+
+        /*
+         * Use CFS's precise accounting:
+         */
+        temp = (u64)nsec_to_clock_t(p->se.sum_exec_runtime);
+
+        if (total) {
+                temp *= utime;
+                do_div(temp, total);
+        }
+        utime = (clock_t)temp;
+
+        p->prev_utime = max(p->prev_utime, clock_t_to_cputime(utime));
+        return p->prev_utime;
+}
+
+cputime_t task_stime(struct task_struct *p)
+{
+        clock_t stime;
+
+        /*
+         * Use CFS's precise accounting. (we subtract utime from
+         * the total, to make sure the total observed by userspace
+         * grows monotonically - apps rely on that):
+         */
+        stime = nsec_to_clock_t(p->se.sum_exec_runtime) -
+                        cputime_to_clock_t(task_utime(p));
+
+        if (stime >= 0)
+                p->prev_stime = max(p->prev_stime, clock_t_to_cputime(stime));
+
+        return p->prev_stime;
+}
+#endif
+
+inline cputime_t task_gtime(struct task_struct *p)
+{
+        return p->gtime;
+}
+
+/*
  * This function gets called by the timer code, with HZ frequency.
  * We call it with interrupts disabled.
  *
@@ -4669,6 +4728,52 @@ int __sched wait_for_completion_killable(struct completion *x)
 }
 EXPORT_SYMBOL(wait_for_completion_killable);
 
+/**
+ *      try_wait_for_completion - try to decrement a completion without blocking
+ *      @x:     completion structure
+ *
+ *      Returns: 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)
+{
+        int ret = 1;
+
+        spin_lock_irq(&x->wait.lock);
+        if (!x->done)
+                ret = 0;
+        else
+                x->done--;
+        spin_unlock_irq(&x->wait.lock);
+        return ret;
+}
+EXPORT_SYMBOL(try_wait_for_completion);
+
+/**
+ *      completion_done - Test to see if a completion has any waiters
+ *      @x:     completion structure
+ *
+ *      Returns: 0 if there are waiters (wait_for_completion() in progress)
+ *               1 if there are no waiters.
+ *
+ */
+bool completion_done(struct completion *x)
+{
+        int ret = 1;
+
+        spin_lock_irq(&x->wait.lock);
+        if (!x->done)
+                ret = 0;
+        spin_unlock_irq(&x->wait.lock);
+        return ret;
+}
+EXPORT_SYMBOL(completion_done);
+
 static long __sched
 sleep_on_common(wait_queue_head_t *q, int state, long timeout)
 {
@@ -5740,6 +5845,8 @@ static inline void sched_init_granularity(void)
                 sysctl_sched_latency = limit;
 
         sysctl_sched_wakeup_granularity *= factor;
+
+        sysctl_sched_shares_ratelimit *= factor;
 }
 
 #ifdef CONFIG_SMP
@@ -7589,24 +7696,27 @@ static int dattrs_equal(struct sched_domain_attr *cur, int idx_cur,
  * and partition_sched_domains() will fallback to the single partition
  * 'fallback_doms', it also forces the domains to be rebuilt.
  *
+ * If doms_new==NULL it will be replaced with cpu_online_map.
+ * ndoms_new==0 is a special case for destroying existing domains.
+ * It will not create the default domain.
+ *
  * Call with hotplug lock held
  */
 void partition_sched_domains(int ndoms_new, cpumask_t *doms_new,
                              struct sched_domain_attr *dattr_new)
 {
-        int i, j;
+        int i, j, n;
 
         mutex_lock(&sched_domains_mutex);
 
         /* always unregister in case we don't destroy any domains */
         unregister_sched_domain_sysctl();
 
-        if (doms_new == NULL)
-                ndoms_new = 0;
+        n = doms_new ? ndoms_new : 0;
 
         /* Destroy deleted domains */
         for (i = 0; i < ndoms_cur; i++) {
-                for (j = 0; j < ndoms_new; j++) {
+                for (j = 0; j < n; j++) {
                         if (cpus_equal(doms_cur[i], doms_new[j])
                             && dattrs_equal(dattr_cur, i, dattr_new, j))
                                 goto match1;
@@ -7619,7 +7729,6 @@ match1:
 
         if (doms_new == NULL) {
                 ndoms_cur = 0;
-                ndoms_new = 1;
                 doms_new = &fallback_doms;
                 cpus_andnot(doms_new[0], cpu_online_map, cpu_isolated_map);
                 dattr_new = NULL;
@@ -7656,8 +7765,13 @@ match2:
 int arch_reinit_sched_domains(void)
 {
         get_online_cpus();
+
+        /* Destroy domains first to force the rebuild */
+        partition_sched_domains(0, NULL, NULL);
+
         rebuild_sched_domains();
         put_online_cpus();
+
         return 0;
 }
 
@@ -7741,7 +7855,7 @@ static int update_sched_domains(struct notifier_block *nfb,
         case CPU_ONLINE_FROZEN:
         case CPU_DEAD:
         case CPU_DEAD_FROZEN:
-                partition_sched_domains(0, NULL, NULL);
+                partition_sched_domains(1, NULL, NULL);
                 return NOTIFY_OK;
 
         default:
@@ -8462,8 +8576,8 @@ struct task_group *sched_create_group(struct task_group *parent)
         WARN_ON(!parent); /* root should already exist */
 
         tg->parent = parent;
-        list_add_rcu(&tg->siblings, &parent->children);
         INIT_LIST_HEAD(&tg->children);
+        list_add_rcu(&tg->siblings, &parent->children);
         spin_unlock_irqrestore(&task_group_lock, flags);
 
         return tg;
@@ -8795,6 +8909,9 @@ static int sched_rt_global_constraints(void)
         u64 rt_runtime, rt_period;
         int ret = 0;
 
+        if (sysctl_sched_rt_period <= 0)
+                return -EINVAL;
+
         rt_period = ktime_to_ns(tg->rt_bandwidth.rt_period);
         rt_runtime = tg->rt_bandwidth.rt_runtime;
 
@@ -8811,6 +8928,9 @@ static int sched_rt_global_constraints(void)
         unsigned long flags;
         int i;
 
+        if (sysctl_sched_rt_period <= 0)
+                return -EINVAL;
+
         spin_lock_irqsave(&def_rt_bandwidth.rt_runtime_lock, flags);
         for_each_possible_cpu(i) {
                 struct rt_rq *rt_rq = &cpu_rq(i)->rt;