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

…ched

* git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched:
  debug: turn ignore_loglevel into an early param
  sched: remove unused params
  sched: let +nice tasks have smaller impact
  sched: fix high wake up latencies with FAIR_USER_SCHED
  RCU: add help text for "RCU implementation type"

init/Kconfig

@@ -775,6 +775,14 @@ config PREEMPT_NOTIFIERS
 choice
 	prompt "RCU implementation type:"
 	default CLASSIC_RCU
+	help
+	  This allows you to choose either the classic RCU implementation
+	  that is designed for best read-side performance on non-realtime
+	  systems, or the preemptible RCU implementation for best latency
+	  on realtime systems.  Note that some kernel preemption modes
+	  will restrict your choice.
+
+	  Select the default if you are unsure.
 
 config CLASSIC_RCU
 	bool "Classic RCU"

kernel/printk.c

@@ -455,10 +455,10 @@ static int __init ignore_loglevel_setup(char *str)
 	ignore_loglevel = 1;
 	printk(KERN_INFO "debug: ignoring loglevel setting.\n");
 
-	return 1;
+	return 0;
 }
 
-__setup("ignore_loglevel", ignore_loglevel_setup);
+early_param("ignore_loglevel", ignore_loglevel_setup);
 
 /*
  * Write out chars from start to end - 1 inclusive

kernel/sched.c

@@ -1255,12 +1255,12 @@ static int task_hot(struct task_struct *p, u64 now, struct sched_domain *sd);
 
 #define sched_class_highest (&rt_sched_class)
 
-static void inc_nr_running(struct task_struct *p, struct rq *rq)
+static void inc_nr_running(struct rq *rq)
 {
 	rq->nr_running++;
 }
 
-static void dec_nr_running(struct task_struct *p, struct rq *rq)
+static void dec_nr_running(struct rq *rq)
 {
 	rq->nr_running--;
 }
@@ -1354,7 +1354,7 @@ static void activate_task(struct rq *rq, struct task_struct *p, int wakeup)
 		rq->nr_uninterruptible--;
 
 	enqueue_task(rq, p, wakeup);
-	inc_nr_running(p, rq);
+	inc_nr_running(rq);
 }
 
 /*
@@ -1366,7 +1366,7 @@ static void deactivate_task(struct rq *rq, struct task_struct *p, int sleep)
 		rq->nr_uninterruptible++;
 
 	dequeue_task(rq, p, sleep);
-	dec_nr_running(p, rq);
+	dec_nr_running(rq);
 }
 
 /**
@@ -2006,7 +2006,7 @@ void fastcall wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
 		 * management (if any):
 		 */
 		p->sched_class->task_new(rq, p);
-		inc_nr_running(p, rq);
+		inc_nr_running(rq);
 	}
 	check_preempt_curr(rq, p);
 #ifdef CONFIG_SMP

kernel/sched_fair.c

@@ -520,7 +520,7 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
 
 	if (!initial) {
 		/* sleeps upto a single latency don't count. */
-		if (sched_feat(NEW_FAIR_SLEEPERS) && entity_is_task(se))
+		if (sched_feat(NEW_FAIR_SLEEPERS))
 			vruntime -= sysctl_sched_latency;
 
 		/* ensure we never gain time by being placed backwards. */
@@ -1106,7 +1106,11 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p)
 	}
 
 	gran = sysctl_sched_wakeup_granularity;
-	if (unlikely(se->load.weight != NICE_0_LOAD))
+	/*
+	 * More easily preempt - nice tasks, while not making
+	 * it harder for + nice tasks.
+	 */
+	if (unlikely(se->load.weight > NICE_0_LOAD))
 		gran = calc_delta_fair(gran, &se->load);
 
 	if (pse->vruntime + gran < se->vruntime)