Merge branch 'proc' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/proc

[linux-2.6-omap-h63xx.git] / kernel / sched.c

diff --git a/kernel/sched.c b/kernel/sched.c
index 5a70189d50519b828b1c95c28b5598df342aa556..6625c3c4b10d06c3f76c371becd615d174244902 100644 (file)
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -228,9 +228,8 @@ static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
 
                now = hrtimer_cb_get_time(&rt_b->rt_period_timer);
                hrtimer_forward(&rt_b->rt_period_timer, now, rt_b->rt_period);
-               hrtimer_start(&rt_b->rt_period_timer,
-                             rt_b->rt_period_timer.expires,
-                             HRTIMER_MODE_ABS);
+               hrtimer_start_expires(&rt_b->rt_period_timer,
+                               HRTIMER_MODE_ABS);
        }
        spin_unlock(&rt_b->rt_runtime_lock);
 }
@@ -819,6 +818,13 @@ const_debug unsigned int sysctl_sched_nr_migrate = 32;
  */
 unsigned int sysctl_sched_shares_ratelimit = 250000;
 
+/*
+ * Inject some fuzzyness into changing the per-cpu group shares
+ * this avoids remote rq-locks at the expense of fairness.
+ * default: 4
+ */
+unsigned int sysctl_sched_shares_thresh = 4;
+
 /*
  * period over which we measure -rt task cpu usage in us.
  * default: 1s
@@ -1065,7 +1071,7 @@ static void hrtick_start(struct rq *rq, u64 delay)
        struct hrtimer *timer = &rq->hrtick_timer;
        ktime_t time = ktime_add_ns(timer->base->get_time(), delay);
 
-       timer->expires = time;
+       hrtimer_set_expires(timer, time);
 
        if (rq == this_rq()) {
                hrtimer_restart(timer);
@@ -1455,8 +1461,8 @@ static void __set_se_shares(struct sched_entity *se, unsigned long shares);
  * Calculate and set the cpu's group shares.
  */
 static void
-__update_group_shares_cpu(struct task_group *tg, int cpu,
-                         unsigned long sd_shares, unsigned long sd_rq_weight)
+update_group_shares_cpu(struct task_group *tg, int cpu,
+                       unsigned long sd_shares, unsigned long sd_rq_weight)
 {
        int boost = 0;
        unsigned long shares;
@@ -1487,19 +1493,23 @@ __update_group_shares_cpu(struct task_group *tg, int cpu,
         *
         */
        shares = (sd_shares * rq_weight) / (sd_rq_weight + 1);
+       shares = clamp_t(unsigned long, shares, MIN_SHARES, MAX_SHARES);
 
-       /*
-        * record the actual number of shares, not the boosted amount.
-        */
-       tg->cfs_rq[cpu]->shares = boost ? 0 : shares;
-       tg->cfs_rq[cpu]->rq_weight = rq_weight;
+       if (abs(shares - tg->se[cpu]->load.weight) >
+                       sysctl_sched_shares_thresh) {
+               struct rq *rq = cpu_rq(cpu);
+               unsigned long flags;
 
-       if (shares < MIN_SHARES)
-               shares = MIN_SHARES;
-       else if (shares > MAX_SHARES)
-               shares = MAX_SHARES;
+               spin_lock_irqsave(&rq->lock, flags);
+               /*
+                * record the actual number of shares, not the boosted amount.
+                */
+               tg->cfs_rq[cpu]->shares = boost ? 0 : shares;
+               tg->cfs_rq[cpu]->rq_weight = rq_weight;
 
-       __set_se_shares(tg->se[cpu], shares);
+               __set_se_shares(tg->se[cpu], shares);
+               spin_unlock_irqrestore(&rq->lock, flags);
+       }
 }
 
 /*
@@ -1528,14 +1538,8 @@ static int tg_shares_up(struct task_group *tg, void *data)
        if (!rq_weight)
                rq_weight = cpus_weight(sd->span) * NICE_0_LOAD;
 
-       for_each_cpu_mask(i, sd->span) {
-               struct rq *rq = cpu_rq(i);
-               unsigned long flags;
-
-               spin_lock_irqsave(&rq->lock, flags);
-               __update_group_shares_cpu(tg, i, shares, rq_weight);
-               spin_unlock_irqrestore(&rq->lock, flags);
-       }
+       for_each_cpu_mask(i, sd->span)
+               update_group_shares_cpu(tg, i, shares, rq_weight);
 
        return 0;
 }
@@ -4444,12 +4448,8 @@ need_resched_nonpreemptible:
        if (sched_feat(HRTICK))
                hrtick_clear(rq);
 
-       /*
-        * Do the rq-clock update outside the rq lock:
-        */
-       local_irq_disable();
+       spin_lock_irq(&rq->lock);
        update_rq_clock(rq);
-       spin_lock(&rq->lock);
        clear_tsk_need_resched(prev);
 
        if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) {