1 files changed, 30 insertions, 46 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index b18f231a4875..38933cafea8a 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -52,7 +52,6 @@
 #include <linux/cpu.h>
 #include <linux/cpuset.h>
 #include <linux/percpu.h>
-#include <linux/cpu_acct.h>
 #include <linux/kthread.h>
 #include <linux/seq_file.h>
 #include <linux/sysctl.h>
@@ -217,15 +216,15 @@ static inline struct task_group *task_group(struct task_struct *p)
 }
 
 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
-static inline void set_task_cfs_rq(struct task_struct *p)
+static inline void set_task_cfs_rq(struct task_struct *p, unsigned int cpu)
 {
-        p->se.cfs_rq = task_group(p)->cfs_rq[task_cpu(p)];
-        p->se.parent = task_group(p)->se[task_cpu(p)];
+        p->se.cfs_rq = task_group(p)->cfs_rq[cpu];
+        p->se.parent = task_group(p)->se[cpu];
 }
 
 #else
 
-static inline void set_task_cfs_rq(struct task_struct *p) { }
+static inline void set_task_cfs_rq(struct task_struct *p, unsigned int cpu) { }
 
 #endif  /* CONFIG_FAIR_GROUP_SCHED */
 
@@ -456,18 +455,18 @@ static void update_rq_clock(struct rq *rq)
  */
 enum {
         SCHED_FEAT_NEW_FAIR_SLEEPERS    = 1,
-        SCHED_FEAT_START_DEBIT          = 2,
-        SCHED_FEAT_TREE_AVG             = 4,
-        SCHED_FEAT_APPROX_AVG           = 8,
-        SCHED_FEAT_WAKEUP_PREEMPT       = 16,
+        SCHED_FEAT_WAKEUP_PREEMPT       = 2,
+        SCHED_FEAT_START_DEBIT          = 4,
+        SCHED_FEAT_TREE_AVG             = 8,
+        SCHED_FEAT_APPROX_AVG           = 16,
 };
 
 const_debug unsigned int sysctl_sched_features =
                 SCHED_FEAT_NEW_FAIR_SLEEPERS    * 1 |
+                SCHED_FEAT_WAKEUP_PREEMPT       * 1 |
                 SCHED_FEAT_START_DEBIT          * 1 |
                 SCHED_FEAT_TREE_AVG             * 0 |
-                SCHED_FEAT_APPROX_AVG           * 0 |
-                SCHED_FEAT_WAKEUP_PREEMPT       * 1;
+                SCHED_FEAT_APPROX_AVG           * 0;
 
 #define sched_feat(x) (sysctl_sched_features & SCHED_FEAT_##x)
 
@@ -1023,10 +1022,16 @@ unsigned long weighted_cpuload(const int cpu)
 
 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
 {
+        set_task_cfs_rq(p, cpu);
 #ifdef CONFIG_SMP
+        /*
+         * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
+         * successfuly executed on another CPU. We must ensure that updates of
+         * per-task data have been completed by this moment.
+         */
+        smp_wmb();
         task_thread_info(p)->cpu = cpu;
 #endif
-        set_task_cfs_rq(p);
 }
 
 #ifdef CONFIG_SMP
@@ -3338,13 +3343,9 @@ void account_user_time(struct task_struct *p, cputime_t cputime)
 {
         struct cpu_usage_stat *cpustat = &kstat_this_cpu.cpustat;
         cputime64_t tmp;
-        struct rq *rq = this_rq();
 
         p->utime = cputime_add(p->utime, cputime);
 
-        if (p != rq->idle)
-                cpuacct_charge(p, cputime);
-
         /* Add user time to cpustat. */
         tmp = cputime_to_cputime64(cputime);
         if (TASK_NICE(p) > 0)
@@ -3395,10 +3396,8 @@ void account_system_time(struct task_struct *p, int hardirq_offset,
         struct rq *rq = this_rq();
         cputime64_t tmp;
 
-        if (p->flags & PF_VCPU) {
-                account_guest_time(p, cputime);
-                return;
-        }
+        if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0))
+                return account_guest_time(p, cputime);
 
         p->stime = cputime_add(p->stime, cputime);
 
@@ -3408,10 +3407,9 @@ void account_system_time(struct task_struct *p, int hardirq_offset,
                 cpustat->irq = cputime64_add(cpustat->irq, tmp);
         else if (softirq_count())
                 cpustat->softirq = cputime64_add(cpustat->softirq, tmp);
-        else if (p != rq->idle) {
+        else if (p != rq->idle)
                 cpustat->system = cputime64_add(cpustat->system, tmp);
-                cpuacct_charge(p, cputime);
-        } else if (atomic_read(&rq->nr_iowait) > 0)
+        else if (atomic_read(&rq->nr_iowait) > 0)
                 cpustat->iowait = cputime64_add(cpustat->iowait, tmp);
         else
                 cpustat->idle = cputime64_add(cpustat->idle, tmp);
@@ -3447,10 +3445,8 @@ void account_steal_time(struct task_struct *p, cputime_t steal)
                         cpustat->iowait = cputime64_add(cpustat->iowait, tmp);
                 else
                         cpustat->idle = cputime64_add(cpustat->idle, tmp);
-        } else {
+        } else
                 cpustat->steal = cputime64_add(cpustat->steal, tmp);
-                cpuacct_charge(p, -tmp);
-        }
 }
 
 /*
@@ -5286,23 +5282,9 @@ static void migrate_live_tasks(int src_cpu)
 }
 
 /*
- * activate_idle_task - move idle task to the _front_ of runqueue.
- */
-static void activate_idle_task(struct task_struct *p, struct rq *rq)
-{
-        update_rq_clock(rq);
-
-        if (p->state == TASK_UNINTERRUPTIBLE)
-                rq->nr_uninterruptible--;
-
-        enqueue_task(rq, p, 0);
-        inc_nr_running(p, rq);
-}
-
-/*
  * Schedules idle task to be the next runnable task on current CPU.
- * It does so by boosting its priority to highest possible and adding it to
- * the _front_ of the runqueue. Used by CPU offline code.
+ * It does so by boosting its priority to highest possible.
+ * Used by CPU offline code.
  */
 void sched_idle_next(void)
 {
@@ -5322,8 +5304,8 @@ void sched_idle_next(void)
 
         __setscheduler(rq, p, SCHED_FIFO, MAX_RT_PRIO-1);
 
-        /* Add idle task to the _front_ of its priority queue: */
-        activate_idle_task(p, rq);
+        update_rq_clock(rq);
+        activate_task(rq, p, 0);
 
         spin_unlock_irqrestore(&rq->lock, flags);
 }
@@ -7097,8 +7079,10 @@ void sched_move_task(struct task_struct *tsk)
 
         rq = task_rq_lock(tsk, &flags);
 
-        if (tsk->sched_class != &fair_sched_class)
+        if (tsk->sched_class != &fair_sched_class) {
+                set_task_cfs_rq(tsk, task_cpu(tsk));
                 goto done;
+        }
 
         update_rq_clock(rq);
 
@@ -7111,7 +7095,7 @@ void sched_move_task(struct task_struct *tsk)
                         tsk->sched_class->put_prev_task(rq, tsk);
         }
 
-        set_task_cfs_rq(tsk);
+        set_task_cfs_rq(tsk, task_cpu(tsk));
 
         if (on_rq) {
                 if (unlikely(running))