4 files changed, 21 insertions, 9 deletions

diff --git a/init/Kconfig b/init/Kconfig
index 0d0bbf218f1f..dcc96a8c8c69 100644
--- a/init/Kconfig
+++ b/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"
diff --git a/kernel/printk.c b/kernel/printk.c
index 58bbec684119..29ae1e99cde0 100644
--- a/kernel/printk.c
+++ b/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
diff --git a/kernel/sched.c b/kernel/sched.c
index ba4c88088f62..8355e007e021 100644
--- a/kernel/sched.c
+++ b/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
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 72e25c7a3a18..6c091d6e159d 100644
--- a/kernel/sched_fair.c
+++ b/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)