Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler fixes from Ingo Molnar:
 "The biggest commit is an irqtime accounting loop latency fix, the rest
  are misc fixes all over the place: deadline scheduling, docs, numa,
  balancer and a bad to-idle latency fix"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/numa: Initialize newidle balance stats in sd_numa_init()
  sched: Fix updating rq->max_idle_balance_cost and rq->next_balance in idle_balance()
  sched: Skip double execution of pick_next_task_fair()
  sched: Use CPUPRI_NR_PRIORITIES instead of MAX_RT_PRIO in cpupri check
  sched/deadline: Fix memory leak
  sched/deadline: Fix sched_yield() behavior
  sched: Sanitize irq accounting madness
  sched/docbook: Fix 'make htmldocs' warnings caused by missing description

6 files changed, 42 insertions, 33 deletions

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index d9d8ece46a15..204d3d281809 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2592,8 +2592,14 @@ pick_next_task(struct rq *rq, struct task_struct *prev)
         if (likely(prev->sched_class == class &&
                    rq->nr_running == rq->cfs.h_nr_running)) {
                 p = fair_sched_class.pick_next_task(rq, prev);
-                if (likely(p && p != RETRY_TASK))
-                        return p;
+                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:
@@ -3124,6 +3130,7 @@ __setparam_dl(struct task_struct *p, const struct sched_attr *attr)
         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,
@@ -3639,6 +3646,7 @@ 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)
@@ -3783,6 +3791,7 @@ err_size:
  * @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)
@@ -6017,6 +6026,8 @@ sd_numa_init(struct sched_domain_topology_level *tl, int cpu)
                                         ,
                 .last_balance           = jiffies,
                 .balance_interval       = sd_weight,
+                .max_newidle_lb_cost    = 0,
+                .next_decay_max_lb_cost = jiffies,
         };
         SD_INIT_NAME(sd, NUMA);
         sd->private = &tl->data;
diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c
index 5b9bb42b2d47..ab001b5d5048 100644
--- a/kernel/sched/cpudeadline.c
+++ b/kernel/sched/cpudeadline.c
@@ -210,7 +210,5 @@ int cpudl_init(struct cpudl *cp)
  */
 void cpudl_cleanup(struct cpudl *cp)
 {
-        /*
-         * nothing to do for the moment
-         */
+        free_cpumask_var(cp->free_cpus);
 }
diff --git a/kernel/sched/cpupri.c b/kernel/sched/cpupri.c
index 8b836b376d91..3031bac8aa3e 100644
--- a/kernel/sched/cpupri.c
+++ b/kernel/sched/cpupri.c
@@ -70,8 +70,7 @@ int cpupri_find(struct cpupri *cp, struct task_struct *p,
         int idx = 0;
         int task_pri = convert_prio(p->prio);
 
-        if (task_pri >= MAX_RT_PRIO)
-                return 0;
+        BUG_ON(task_pri >= CPUPRI_NR_PRIORITIES);
 
         for (idx = 0; idx < task_pri; idx++) {
                 struct cpupri_vec *vec  = &cp->pri_to_cpu[idx];
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index a95097cb4591..72fdf06ef865 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -332,50 +332,50 @@ out:
  * softirq as those do not count in task exec_runtime any more.
  */
 static void irqtime_account_process_tick(struct task_struct *p, int user_tick,
-                                                struct rq *rq)
+                                         struct rq *rq, int ticks)
 {
-        cputime_t one_jiffy_scaled = cputime_to_scaled(cputime_one_jiffy);
+        cputime_t scaled = cputime_to_scaled(cputime_one_jiffy);
+        u64 cputime = (__force u64) cputime_one_jiffy;
         u64 *cpustat = kcpustat_this_cpu->cpustat;
 
         if (steal_account_process_tick())
                 return;
 
+        cputime *= ticks;
+        scaled *= ticks;
+
         if (irqtime_account_hi_update()) {
-                cpustat[CPUTIME_IRQ] += (__force u64) cputime_one_jiffy;
+                cpustat[CPUTIME_IRQ] += cputime;
         } else if (irqtime_account_si_update()) {
-                cpustat[CPUTIME_SOFTIRQ] += (__force u64) cputime_one_jiffy;
+                cpustat[CPUTIME_SOFTIRQ] += cputime;
         } else if (this_cpu_ksoftirqd() == p) {
                 /*
                  * ksoftirqd time do not get accounted in cpu_softirq_time.
                  * So, we have to handle it separately here.
                  * Also, p->stime needs to be updated for ksoftirqd.
                  */
-                __account_system_time(p, cputime_one_jiffy, one_jiffy_scaled,
-                                        CPUTIME_SOFTIRQ);
+                __account_system_time(p, cputime, scaled, CPUTIME_SOFTIRQ);
         } else if (user_tick) {
-                account_user_time(p, cputime_one_jiffy, one_jiffy_scaled);
+                account_user_time(p, cputime, scaled);
         } else if (p == rq->idle) {
-                account_idle_time(cputime_one_jiffy);
+                account_idle_time(cputime);
         } else if (p->flags & PF_VCPU) { /* System time or guest time */
-                account_guest_time(p, cputime_one_jiffy, one_jiffy_scaled);
+                account_guest_time(p, cputime, scaled);
         } else {
-                __account_system_time(p, cputime_one_jiffy, one_jiffy_scaled,
-                                        CPUTIME_SYSTEM);
+                __account_system_time(p, cputime, scaled,       CPUTIME_SYSTEM);
         }
 }
 
 static void irqtime_account_idle_ticks(int ticks)
 {
-        int i;
         struct rq *rq = this_rq();
 
-        for (i = 0; i < ticks; i++)
-                irqtime_account_process_tick(current, 0, rq);
+        irqtime_account_process_tick(current, 0, rq, ticks);
 }
 #else /* CONFIG_IRQ_TIME_ACCOUNTING */
 static inline void irqtime_account_idle_ticks(int ticks) {}
 static inline void irqtime_account_process_tick(struct task_struct *p, int user_tick,
-                                                struct rq *rq) {}
+                                                struct rq *rq, int nr_ticks) {}
 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
 
 /*
@@ -464,7 +464,7 @@ void account_process_tick(struct task_struct *p, int user_tick)
                 return;
 
         if (sched_clock_irqtime) {
-                irqtime_account_process_tick(p, user_tick, rq);
+                irqtime_account_process_tick(p, user_tick, rq, 1);
                 return;
         }
 
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index b08095786cb8..800e99b99075 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -528,6 +528,7 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
         sched_clock_tick();
         update_rq_clock(rq);
         dl_se->dl_throttled = 0;
+        dl_se->dl_yielded = 0;
         if (p->on_rq) {
                 enqueue_task_dl(rq, p, ENQUEUE_REPLENISH);
                 if (task_has_dl_policy(rq->curr))
@@ -893,10 +894,10 @@ static void yield_task_dl(struct rq *rq)
          * We make the task go to sleep until its current deadline by
          * forcing its runtime to zero. This way, update_curr_dl() stops
          * it and the bandwidth timer will wake it up and will give it
-         * new scheduling parameters (thanks to dl_new=1).
+         * new scheduling parameters (thanks to dl_yielded=1).
          */
         if (p->dl.runtime > 0) {
-                rq->curr->dl.dl_new = 1;
+                rq->curr->dl.dl_yielded = 1;
                 p->dl.runtime = 0;
         }
         update_curr_dl(rq);
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 7570dd969c28..0fdb96de81a5 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -6653,6 +6653,7 @@ static int idle_balance(struct rq *this_rq)
         int this_cpu = this_rq->cpu;
 
         idle_enter_fair(this_rq);
+
         /*
          * We must set idle_stamp _before_ calling idle_balance(), such that we
          * measure the duration of idle_balance() as idle time.
@@ -6705,14 +6706,16 @@ static int idle_balance(struct rq *this_rq)
 
         raw_spin_lock(&this_rq->lock);
 
+        if (curr_cost > this_rq->max_idle_balance_cost)
+                this_rq->max_idle_balance_cost = curr_cost;
+
         /*
-         * While browsing the domains, we released the rq lock.
-         * A task could have be enqueued in the meantime
+         * While browsing the domains, we released the rq lock, a task could
+         * have been enqueued in the meantime. Since we're not going idle,
+         * pretend we pulled a task.
          */
-        if (this_rq->cfs.h_nr_running && !pulled_task) {
+        if (this_rq->cfs.h_nr_running && !pulled_task)
                 pulled_task = 1;
-                goto out;
-        }
 
         if (pulled_task || time_after(jiffies, this_rq->next_balance)) {
                 /*
@@ -6722,9 +6725,6 @@ static int idle_balance(struct rq *this_rq)
                 this_rq->next_balance = next_balance;
         }
 
-        if (curr_cost > this_rq->max_idle_balance_cost)
-                this_rq->max_idle_balance_cost = curr_cost;
-
 out:
         /* Is there a task of a high priority class? */
         if (this_rq->nr_running != this_rq->cfs.h_nr_running &&