5 files changed, 38 insertions, 72 deletions

diff --git a/kernel/sched/clock.c b/kernel/sched/clock.c
index c685e31492df..c3ae1446461c 100644
--- a/kernel/sched/clock.c
+++ b/kernel/sched/clock.c
@@ -176,10 +176,36 @@ static u64 sched_clock_remote(struct sched_clock_data *scd)
         u64 this_clock, remote_clock;
         u64 *ptr, old_val, val;
 
+#if BITS_PER_LONG != 64
+again:
+        /*
+         * Careful here: The local and the remote clock values need to
+         * be read out atomic as we need to compare the values and
+         * then update either the local or the remote side. So the
+         * cmpxchg64 below only protects one readout.
+         *
+         * We must reread via sched_clock_local() in the retry case on
+         * 32bit as an NMI could use sched_clock_local() via the
+         * tracer and hit between the readout of
+         * the low32bit and the high 32bit portion.
+         */
+        this_clock = sched_clock_local(my_scd);
+        /*
+         * We must enforce atomic readout on 32bit, otherwise the
+         * update on the remote cpu can hit inbetween the readout of
+         * the low32bit and the high 32bit portion.
+         */
+        remote_clock = cmpxchg64(&scd->clock, 0, 0);
+#else
+        /*
+         * On 64bit the read of [my]scd->clock is atomic versus the
+         * update, so we can avoid the above 32bit dance.
+         */
         sched_clock_local(my_scd);
 again:
         this_clock = my_scd->clock;
         remote_clock = scd->clock;
+#endif
 
         /*
          * Use the opportunity that we have both locks
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index cb49b2ab0e16..5662f58f0b69 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -512,11 +512,6 @@ static inline void init_hrtick(void)
  * the target CPU.
  */
 #ifdef CONFIG_SMP
-
-#ifndef tsk_is_polling
-#define tsk_is_polling(t) 0
-#endif
-
 void resched_task(struct task_struct *p)
 {
         int cpu;
@@ -1498,8 +1493,10 @@ static void try_to_wake_up_local(struct task_struct *p)
 {
         struct rq *rq = task_rq(p);
 
-        BUG_ON(rq != this_rq());
-        BUG_ON(p == current);
+        if (WARN_ON_ONCE(rq != this_rq()) ||
+            WARN_ON_ONCE(p == current))
+                return;
+
         lockdep_assert_held(&rq->lock);
 
         if (!raw_spin_trylock(&p->pi_lock)) {
@@ -2997,51 +2994,6 @@ void __sched schedule_preempt_disabled(void)
         preempt_disable();
 }
 
-#ifdef CONFIG_MUTEX_SPIN_ON_OWNER
-
-static inline bool owner_running(struct mutex *lock, struct task_struct *owner)
-{
-        if (lock->owner != owner)
-                return false;
-
-        /*
-         * Ensure we emit the owner->on_cpu, dereference _after_ checking
-         * lock->owner still matches owner, if that fails, owner might
-         * point to free()d memory, if it still matches, the rcu_read_lock()
-         * ensures the memory stays valid.
-         */
-        barrier();
-
-        return owner->on_cpu;
-}
-
-/*
- * Look out! "owner" is an entirely speculative pointer
- * access and not reliable.
- */
-int mutex_spin_on_owner(struct mutex *lock, struct task_struct *owner)
-{
-        if (!sched_feat(OWNER_SPIN))
-                return 0;
-
-        rcu_read_lock();
-        while (owner_running(lock, owner)) {
-                if (need_resched())
-                        break;
-
-                arch_mutex_cpu_relax();
-        }
-        rcu_read_unlock();
-
-        /*
-         * We break out the loop above on need_resched() and when the
-         * owner changed, which is a sign for heavy contention. Return
-         * success only when lock->owner is NULL.
-         */
-        return lock->owner == NULL;
-}
-#endif
-
 #ifdef CONFIG_PREEMPT
 /*
  * this is the entry point to schedule() from in-kernel preemption
@@ -4130,6 +4082,10 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask)
         get_task_struct(p);
         rcu_read_unlock();
 
+        if (p->flags & PF_NO_SETAFFINITY) {
+                retval = -EINVAL;
+                goto out_put_task;
+        }
         if (!alloc_cpumask_var(&cpus_allowed, GFP_KERNEL)) {
                 retval = -ENOMEM;
                 goto out_put_task;
@@ -4630,6 +4586,7 @@ void sched_show_task(struct task_struct *p)
                 task_pid_nr(p), ppid,
                 (unsigned long)task_thread_info(p)->flags);
 
+        print_worker_info(KERN_INFO, p);
         show_stack(p, NULL);
 }
 
@@ -4777,11 +4734,6 @@ int set_cpus_allowed_ptr(struct task_struct *p, const struct cpumask *new_mask)
                 goto out;
         }
 
-        if (unlikely((p->flags & PF_THREAD_BOUND) && p != current)) {
-                ret = -EINVAL;
-                goto out;
-        }
-
         do_set_cpus_allowed(p, new_mask);
 
         /* Can the task run on the task's current CPU? If so, we're done */
@@ -5003,7 +4955,7 @@ static void sd_free_ctl_entry(struct ctl_table **tablep)
 }
 
 static int min_load_idx = 0;
-static int max_load_idx = CPU_LOAD_IDX_MAX;
+static int max_load_idx = CPU_LOAD_IDX_MAX-1;
 
 static void
 set_table_entry(struct ctl_table *entry,
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index 337a36745800..cc2dc3eea8a3 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -294,7 +294,7 @@ void thread_group_cputime(struct task_struct *tsk, struct task_cputime *times)
 
         t = tsk;
         do {
-                task_cputime(tsk, &utime, &stime);
+                task_cputime(t, &utime, &stime);
                 times->utime += utime;
                 times->stime += stime;
                 times->sum_exec_runtime += task_sched_runtime(t);
diff --git a/kernel/sched/features.h b/kernel/sched/features.h
index 1ad1d2b5395f..99399f8e4799 100644
--- a/kernel/sched/features.h
+++ b/kernel/sched/features.h
@@ -46,13 +46,6 @@ SCHED_FEAT(DOUBLE_TICK, false)
 SCHED_FEAT(LB_BIAS, true)
 
 /*
- * Spin-wait on mutex acquisition when the mutex owner is running on
- * another cpu -- assumes that when the owner is running, it will soon
- * release the lock. Decreases scheduling overhead.
- */
-SCHED_FEAT(OWNER_SPIN, true)
-
-/*
  * Decrement CPU power based on time not spent running tasks
  */
 SCHED_FEAT(NONTASK_POWER, true)
diff --git a/kernel/sched/stats.c b/kernel/sched/stats.c
index e036eda1a9c9..da98af347e8b 100644
--- a/kernel/sched/stats.c
+++ b/kernel/sched/stats.c
@@ -130,16 +130,11 @@ static int schedstat_open(struct inode *inode, struct file *file)
         return seq_open(file, &schedstat_sops);
 }
 
-static int schedstat_release(struct inode *inode, struct file *file)
-{
-        return 0;
-};
-
 static const struct file_operations proc_schedstat_operations = {
         .open    = schedstat_open,
         .read    = seq_read,
         .llseek  = seq_lseek,
-        .release = schedstat_release,
+        .release = seq_release,
 };
 
 static int __init proc_schedstat_init(void)