Merge git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched

* git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched:
  [PATCH] sched: implement cpu_clock(cpu) high-speed time source
  [PATCH] sched: fix the all pinned logic in load_balance_newidle()
  [PATCH] sched: fix newly idle load balance in case of SMT
  [PATCH] sched: sched_cacheflush is now unused

1 files changed, 26 insertions, 5 deletions

diff --git a/kernel/sched.c b/kernel/sched.c
index 645256b228c3..93cf241cfbe9 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -379,6 +379,23 @@ static inline unsigned long long rq_clock(struct rq *rq)
 #define task_rq(p)              cpu_rq(task_cpu(p))
 #define cpu_curr(cpu)           (cpu_rq(cpu)->curr)
 
+/*
+ * For kernel-internal use: high-speed (but slightly incorrect) per-cpu
+ * clock constructed from sched_clock():
+ */
+unsigned long long cpu_clock(int cpu)
+{
+        struct rq *rq = cpu_rq(cpu);
+        unsigned long long now;
+        unsigned long flags;
+
+        spin_lock_irqsave(&rq->lock, flags);
+        now = rq_clock(rq);
+        spin_unlock_irqrestore(&rq->lock, flags);
+
+        return now;
+}
+
 #ifdef CONFIG_FAIR_GROUP_SCHED
 /* Change a task's ->cfs_rq if it moves across CPUs */
 static inline void set_task_cfs_rq(struct task_struct *p)
@@ -2235,7 +2252,7 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
 
                         rq = cpu_rq(i);
 
-                        if (*sd_idle && !idle_cpu(i))
+                        if (*sd_idle && rq->nr_running)
                                 *sd_idle = 0;
 
                         /* Bias balancing toward cpus of our domain */
@@ -2257,9 +2274,11 @@ find_busiest_group(struct sched_domain *sd, int this_cpu,
                 /*
                  * First idle cpu or the first cpu(busiest) in this sched group
                  * is eligible for doing load balancing at this and above
-                 * domains.
+                 * domains. In the newly idle case, we will allow all the cpu's
+                 * to do the newly idle load balance.
                  */
-                if (local_group && balance_cpu != this_cpu && balance) {
+                if (idle != CPU_NEWLY_IDLE && local_group &&
+                    balance_cpu != this_cpu && balance) {
                         *balance = 0;
                         goto ret;
                 }
@@ -2677,6 +2696,7 @@ load_balance_newidle(int this_cpu, struct rq *this_rq, struct sched_domain *sd)
         unsigned long imbalance;
         int nr_moved = 0;
         int sd_idle = 0;
+        int all_pinned = 0;
         cpumask_t cpus = CPU_MASK_ALL;
 
         /*
@@ -2715,10 +2735,11 @@ redo:
                 double_lock_balance(this_rq, busiest);
                 nr_moved = move_tasks(this_rq, this_cpu, busiest,
                                         minus_1_or_zero(busiest->nr_running),
-                                        imbalance, sd, CPU_NEWLY_IDLE, NULL);
+                                        imbalance, sd, CPU_NEWLY_IDLE,
+                                        &all_pinned);
                 spin_unlock(&busiest->lock);
 
-                if (!nr_moved) {
+                if (unlikely(all_pinned)) {
                         cpu_clear(cpu_of(busiest), cpus);
                         if (!cpus_empty(cpus))
                                 goto redo;