Merge branch 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull NOHZ updates from Thomas Gleixner:
 "A few updates to the nohz infrastructure:

   - recursion protection for context tracking

   - make the TIF_NOHZ inheritance smarter

   - isolate cpus which belong to the NOHZ full set"

* 'timers-nohz-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  nohz: Set isolcpus when nohz_full is set
  nohz: Add tick_nohz_full_add_cpus_to() API
  context_tracking: Inherit TIF_NOHZ through forks instead of context switches
  context_tracking: Protect against recursion

include/linux/sched.h

@@ -2599,6 +2599,9 @@ static inline unsigned long wait_task_inactive(struct task_struct *p,
 }
 #endif
 
+#define tasklist_empty() \
+	list_empty(&init_task.tasks)
+
 #define next_task(p) \
 	list_entry_rcu((p)->tasks.next, struct task_struct, tasks)