8 files changed, 49 insertions, 40 deletions

diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index f227bc172690..827cd9adccb2 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -843,37 +843,25 @@ static void cpuset_change_cpumask(struct task_struct *tsk,
 /**
  * update_tasks_cpumask - Update the cpumasks of tasks in the cpuset.
  * @cs: the cpuset in which each task's cpus_allowed mask needs to be changed
+ * @heap: if NULL, defer allocating heap memory to cgroup_scan_tasks()
  *
  * Called with cgroup_mutex held
  *
  * The cgroup_scan_tasks() function will scan all the tasks in a cgroup,
  * calling callback functions for each.
  *
- * Return 0 if successful, -errno if not.
+ * No return value. It's guaranteed that cgroup_scan_tasks() always returns 0
+ * if @heap != NULL.
  */
-static int update_tasks_cpumask(struct cpuset *cs)
+static void update_tasks_cpumask(struct cpuset *cs, struct ptr_heap *heap)
 {
         struct cgroup_scanner scan;
-        struct ptr_heap heap;
-        int retval;
-
-        /*
-         * cgroup_scan_tasks() will initialize heap->gt for us.
-         * heap_init() is still needed here for we should not change
-         * cs->cpus_allowed when heap_init() fails.
-         */
-        retval = heap_init(&heap, PAGE_SIZE, GFP_KERNEL, NULL);
-        if (retval)
-                return retval;
 
         scan.cg = cs->css.cgroup;
         scan.test_task = cpuset_test_cpumask;
         scan.process_task = cpuset_change_cpumask;
-        scan.heap = &heap;
-        retval = cgroup_scan_tasks(&scan);
-
-        heap_free(&heap);
-        return retval;
+        scan.heap = heap;
+        cgroup_scan_tasks(&scan);
 }
 
 /**
@@ -883,6 +871,7 @@ static int update_tasks_cpumask(struct cpuset *cs)
  */
 static int update_cpumask(struct cpuset *cs, const char *buf)
 {
+        struct ptr_heap heap;
         struct cpuset trialcs;
         int retval;
         int is_load_balanced;
@@ -917,6 +906,10 @@ static int update_cpumask(struct cpuset *cs, const char *buf)
         if (cpus_equal(cs->cpus_allowed, trialcs.cpus_allowed))
                 return 0;
 
+        retval = heap_init(&heap, PAGE_SIZE, GFP_KERNEL, NULL);
+        if (retval)
+                return retval;
+
         is_load_balanced = is_sched_load_balance(&trialcs);
 
         mutex_lock(&callback_mutex);
@@ -927,9 +920,9 @@ static int update_cpumask(struct cpuset *cs, const char *buf)
          * Scan tasks in the cpuset, and update the cpumasks of any
          * that need an update.
          */
-        retval = update_tasks_cpumask(cs);
-        if (retval < 0)
-                return retval;
+        update_tasks_cpumask(cs, &heap);
+
+        heap_free(&heap);
 
         if (is_load_balanced)
                 async_rebuild_sched_domains();
@@ -1965,7 +1958,7 @@ static void scan_for_empty_cpusets(const struct cpuset *root)
                      nodes_empty(cp->mems_allowed))
                         remove_tasks_in_empty_cpuset(cp);
                 else {
-                        update_tasks_cpumask(cp);
+                        update_tasks_cpumask(cp, NULL);
                         update_tasks_nodemask(cp, &oldmems);
                 }
         }
diff --git a/kernel/sched.c b/kernel/sched.c
index cc1f81b50b82..98890807375b 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -8909,6 +8909,9 @@ static int sched_rt_global_constraints(void)
         u64 rt_runtime, rt_period;
         int ret = 0;
 
+        if (sysctl_sched_rt_period <= 0)
+                return -EINVAL;
+
         rt_period = ktime_to_ns(tg->rt_bandwidth.rt_period);
         rt_runtime = tg->rt_bandwidth.rt_runtime;
 
@@ -8925,6 +8928,9 @@ static int sched_rt_global_constraints(void)
         unsigned long flags;
         int i;
 
+        if (sysctl_sched_rt_period <= 0)
+                return -EINVAL;
+
         spin_lock_irqsave(&def_rt_bandwidth.rt_runtime_lock, flags);
         for_each_possible_cpu(i) {
                 struct rt_rq *rt_rq = &cpu_rq(i)->rt;
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index 552310798dad..1113157b2058 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -350,6 +350,7 @@ static void __enable_runtime(struct rq *rq)
                 spin_lock(&rt_rq->rt_runtime_lock);
                 rt_rq->rt_runtime = rt_b->rt_runtime;
                 rt_rq->rt_time = 0;
+                rt_rq->rt_throttled = 0;
                 spin_unlock(&rt_rq->rt_runtime_lock);
                 spin_unlock(&rt_b->rt_runtime_lock);
         }
diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c
index 1876b526c778..f8d968063cea 100644
--- a/kernel/time/clockevents.c
+++ b/kernel/time/clockevents.c
@@ -72,6 +72,16 @@ void clockevents_set_mode(struct clock_event_device *dev,
 }
 
 /**
+ * clockevents_shutdown - shutdown the device and clear next_event
+ * @dev:        device to shutdown
+ */
+void clockevents_shutdown(struct clock_event_device *dev)
+{
+        clockevents_set_mode(dev, CLOCK_EVT_MODE_SHUTDOWN);
+        dev->next_event.tv64 = KTIME_MAX;
+}
+
+/**
  * clockevents_program_event - Reprogram the clock event device.
  * @expires:    absolute expiry time (monotonic clock)
  *
@@ -206,7 +216,7 @@ void clockevents_exchange_device(struct clock_event_device *old,
 
         if (new) {
                 BUG_ON(new->mode != CLOCK_EVT_MODE_UNUSED);
-                clockevents_set_mode(new, CLOCK_EVT_MODE_SHUTDOWN);
+                clockevents_shutdown(new);
         }
         local_irq_restore(flags);
 }
diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c
index 2f5a38294bf9..f1f3eee28113 100644
--- a/kernel/time/tick-broadcast.c
+++ b/kernel/time/tick-broadcast.c
@@ -236,8 +236,7 @@ static void tick_do_broadcast_on_off(void *why)
                 if (!cpu_isset(cpu, tick_broadcast_mask)) {
                         cpu_set(cpu, tick_broadcast_mask);
                         if (td->mode == TICKDEV_MODE_PERIODIC)
-                                clockevents_set_mode(dev,
-                                                     CLOCK_EVT_MODE_SHUTDOWN);
+                                clockevents_shutdown(dev);
                 }
                 if (*reason == CLOCK_EVT_NOTIFY_BROADCAST_FORCE)
                         tick_broadcast_force = 1;
@@ -254,7 +253,7 @@ static void tick_do_broadcast_on_off(void *why)
 
         if (cpus_empty(tick_broadcast_mask)) {
                 if (!bc_stopped)
-                        clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN);
+                        clockevents_shutdown(bc);
         } else if (bc_stopped) {
                 if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC)
                         tick_broadcast_start_periodic(bc);
@@ -306,7 +305,7 @@ void tick_shutdown_broadcast(unsigned int *cpup)
 
         if (tick_broadcast_device.mode == TICKDEV_MODE_PERIODIC) {
                 if (bc && cpus_empty(tick_broadcast_mask))
-                        clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN);
+                        clockevents_shutdown(bc);
         }
 
         spin_unlock_irqrestore(&tick_broadcast_lock, flags);
@@ -321,7 +320,7 @@ void tick_suspend_broadcast(void)
 
         bc = tick_broadcast_device.evtdev;
         if (bc)
-                clockevents_set_mode(bc, CLOCK_EVT_MODE_SHUTDOWN);
+                clockevents_shutdown(bc);
 
         spin_unlock_irqrestore(&tick_broadcast_lock, flags);
 }
diff --git a/kernel/time/tick-common.c b/kernel/time/tick-common.c
index c4777193d567..019315ebf9de 100644
--- a/kernel/time/tick-common.c
+++ b/kernel/time/tick-common.c
@@ -249,7 +249,7 @@ static int tick_check_new_device(struct clock_event_device *newdev)
          * not give it back to the clockevents layer !
          */
         if (tick_is_broadcast_device(curdev)) {
-                clockevents_set_mode(curdev, CLOCK_EVT_MODE_SHUTDOWN);
+                clockevents_shutdown(curdev);
                 curdev = NULL;
         }
         clockevents_exchange_device(curdev, newdev);
@@ -311,7 +311,7 @@ static void tick_suspend(void)
         unsigned long flags;
 
         spin_lock_irqsave(&tick_device_lock, flags);
-        clockevents_set_mode(td->evtdev, CLOCK_EVT_MODE_SHUTDOWN);
+        clockevents_shutdown(td->evtdev);
         spin_unlock_irqrestore(&tick_device_lock, flags);
 }
 
diff --git a/kernel/time/tick-internal.h b/kernel/time/tick-internal.h
index 0ffc2918ea6f..6e9db9734aa6 100644
--- a/kernel/time/tick-internal.h
+++ b/kernel/time/tick-internal.h
@@ -10,6 +10,8 @@ extern int tick_do_timer_cpu __read_mostly;
 extern void tick_setup_periodic(struct clock_event_device *dev, int broadcast);
 extern void tick_handle_periodic(struct clock_event_device *dev);
 
+extern void clockevents_shutdown(struct clock_event_device *dev);
+
 /*
  * NO_HZ / high resolution timer shared code
  */
diff --git a/kernel/time/tick-oneshot.c b/kernel/time/tick-oneshot.c
index 2e35501e61dd..2e8de678e767 100644
--- a/kernel/time/tick-oneshot.c
+++ b/kernel/time/tick-oneshot.c
@@ -43,19 +43,17 @@ int tick_dev_program_event(struct clock_event_device *dev, ktime_t expires,
                  * and emit a warning.
                  */
                 if (++i > 2) {
-                        printk(KERN_WARNING "CE: __tick_program_event of %s is "
-                               "stuck %llx %llx\n", dev->name ? dev->name : "?",
-                               now.tv64, expires.tv64);
-                        printk(KERN_WARNING
-                               "CE: increasing min_delta_ns %ld to %ld nsec\n",
-                               dev->min_delta_ns, dev->min_delta_ns << 1);
-                        WARN_ON(1);
-
-                        /* Double the min. delta and try again */
+                        /* Increase the min. delta and try again */
                         if (!dev->min_delta_ns)
                                 dev->min_delta_ns = 5000;
                         else
-                                dev->min_delta_ns <<= 1;
+                                dev->min_delta_ns += dev->min_delta_ns >> 1;
+
+                        printk(KERN_WARNING
+                               "CE: %s increasing min_delta_ns to %lu nsec\n",
+                               dev->name ? dev->name : "?",
+                               dev->min_delta_ns << 1);
+
                         i = 0;
                 }