Merge branch 'timers-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...

[sfrench/cifs-2.6.git] / kernel / sched.c

diff --git a/kernel/sched.c b/kernel/sched.c
index 52bbf1c842a8e0baecd1cd9f53883806eaab1350..e72485033c48e0317a22d376e2c290440b40cce9 100644 (file)
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -2266,6 +2266,16 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state, int sync)
        if (!sched_feat(SYNC_WAKEUPS))
                sync = 0;
 
+       if (!sync) {
+               if (current->se.avg_overlap < sysctl_sched_migration_cost &&
+                         p->se.avg_overlap < sysctl_sched_migration_cost)
+                       sync = 1;
+       } else {
+               if (current->se.avg_overlap >= sysctl_sched_migration_cost ||
+                         p->se.avg_overlap >= sysctl_sched_migration_cost)
+                       sync = 0;
+       }
+
 #ifdef CONFIG_SMP
        if (sched_feat(LB_WAKEUP_UPDATE)) {
                struct sched_domain *sd;
@@ -3880,19 +3890,24 @@ int select_nohz_load_balancer(int stop_tick)
        int cpu = smp_processor_id();
 
        if (stop_tick) {
-               cpumask_set_cpu(cpu, nohz.cpu_mask);
                cpu_rq(cpu)->in_nohz_recently = 1;
 
-               /*
-                * If we are going offline and still the leader, give up!
-                */
-               if (!cpu_active(cpu) &&
-                   atomic_read(&nohz.load_balancer) == cpu) {
+               if (!cpu_active(cpu)) {
+                       if (atomic_read(&nohz.load_balancer) != cpu)
+                               return 0;
+
+                       /*
+                        * If we are going offline and still the leader,
+                        * give up!
+                        */
                        if (atomic_cmpxchg(&nohz.load_balancer, cpu, -1) != cpu)
                                BUG();
+
                        return 0;
                }
 
+               cpumask_set_cpu(cpu, nohz.cpu_mask);
+
                /* time for ilb owner also to sleep */
                if (cpumask_weight(nohz.cpu_mask) == num_online_cpus()) {
                        if (atomic_read(&nohz.load_balancer) == cpu)
@@ -4687,8 +4702,8 @@ EXPORT_SYMBOL(default_wake_function);
  * 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 sync, void *key)
+void __wake_up_common(wait_queue_head_t *q, unsigned int mode,
+                       int nr_exclusive, int sync, void *key)
 {
        wait_queue_t *curr, *next;