Merge tag 'trace-v4.14-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

Pull tracing fixlets from Steven Rostedt:
 "Two updates:

   - A memory fix with left over code from spliting out ftrace_ops and
     function graph tracer, where the function graph tracer could reset
     the trampoline pointer, leaving the old trampoline not to be freed
     (memory leak).

   - The update to Paul's patch that added the unnecessary READ_ONCE().
     This removes the unnecessary READ_ONCE() instead of having to
     rebase the branch to update the patch that added it"

* tag 'trace-v4.14-rc1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
  rcu: Remove extraneous READ_ONCE()s from rcu_irq_{enter,exit}()
  ftrace: Fix kmemleak in unregister_ftrace_graph

kernel/rcu/tree.c

@@ -884,7 +884,7 @@ void rcu_irq_exit(void)
 	rdtp = this_cpu_ptr(&rcu_dynticks);
 
 	/* Page faults can happen in NMI handlers, so check... */
-	if (READ_ONCE(rdtp->dynticks_nmi_nesting))
+	if (rdtp->dynticks_nmi_nesting)
 		return;
 
 	WARN_ON_ONCE(IS_ENABLED(CONFIG_RCU_EQS_DEBUG) &&
@@ -1022,7 +1022,7 @@ void rcu_irq_enter(void)
 	rdtp = this_cpu_ptr(&rcu_dynticks);
 
 	/* Page faults can happen in NMI handlers, so check... */
-	if (READ_ONCE(rdtp->dynticks_nmi_nesting))
+	if (rdtp->dynticks_nmi_nesting)
 		return;
 
 	oldval = rdtp->dynticks_nesting;

kernel/trace/ftrace.c

@@ -4954,9 +4954,6 @@ static char ftrace_graph_buf[FTRACE_FILTER_SIZE] __initdata;
 static char ftrace_graph_notrace_buf[FTRACE_FILTER_SIZE] __initdata;
 static int ftrace_graph_set_hash(struct ftrace_hash *hash, char *buffer);
 
-static unsigned long save_global_trampoline;
-static unsigned long save_global_flags;
-
 static int __init set_graph_function(char *str)
 {
 	strlcpy(ftrace_graph_buf, str, FTRACE_FILTER_SIZE);
@@ -6808,17 +6805,6 @@ void unregister_ftrace_graph(void)
 	unregister_pm_notifier(&ftrace_suspend_notifier);
 	unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL);
 
-#ifdef CONFIG_DYNAMIC_FTRACE
-	/*
-	 * Function graph does not allocate the trampoline, but
-	 * other global_ops do. We need to reset the ALLOC_TRAMP flag
-	 * if one was used.
-	 */
-	global_ops.trampoline = save_global_trampoline;
-	if (save_global_flags & FTRACE_OPS_FL_ALLOC_TRAMP)
-		global_ops.flags |= FTRACE_OPS_FL_ALLOC_TRAMP;
-#endif
-
  out:
 	mutex_unlock(&ftrace_lock);
 }