tracing: Convert the tracing facility over to use tracefs

debugfs was fine for the tracing facility as a quick way to get
an interface. Now that tracing has matured, it should separate itself
from debugfs such that it can be mounted separately without needing
to mount all of debugfs with it. That is, users resist using tracing
because it requires mounting debugfs. Having tracing have its own file
system lets users get the features of tracing without needing to bring
in the rest of the kernel's debug infrastructure.

Another reason for tracefs is that debubfs does not support mkdir.
Currently, to create instances, one does a mkdir in the tracing/instance
directory. This is implemented via a hack that forces debugfs to do
something it is not intended on doing. By converting over to tracefs, this
hack can be removed and mkdir can be properly implemented. This patch does
not address this yet, but it lays the ground work for that to be done.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 45e5cb1..fcc0e70 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -18,7 +18,7 @@
 #include <linux/kallsyms.h>
 #include <linux/seq_file.h>
 #include <linux/suspend.h>
-#include <linux/debugfs.h>
+#include <linux/tracefs.h>
 #include <linux/hardirq.h>
 #include <linux/kthread.h>
 #include <linux/uaccess.h>
@@ -1008,7 +1008,7 @@
 	.stat_show	= function_stat_show
 };
 
-static __init void ftrace_profile_debugfs(struct dentry *d_tracer)
+static __init void ftrace_profile_tracefs(struct dentry *d_tracer)
 {
 	struct ftrace_profile_stat *stat;
 	struct dentry *entry;
@@ -1044,15 +1044,15 @@
 		}
 	}
 
-	entry = debugfs_create_file("function_profile_enabled", 0644,
+	entry = tracefs_create_file("function_profile_enabled", 0644,
 				    d_tracer, NULL, &ftrace_profile_fops);
 	if (!entry)
-		pr_warning("Could not create debugfs "
+		pr_warning("Could not create tracefs "
 			   "'function_profile_enabled' entry\n");
 }
 
 #else /* CONFIG_FUNCTION_PROFILER */
-static __init void ftrace_profile_debugfs(struct dentry *d_tracer)
+static __init void ftrace_profile_tracefs(struct dentry *d_tracer)
 {
 }
 #endif /* CONFIG_FUNCTION_PROFILER */
@@ -4690,7 +4690,7 @@
 	mutex_unlock(&ftrace_lock);
 }
 
-static __init int ftrace_init_dyn_debugfs(struct dentry *d_tracer)
+static __init int ftrace_init_dyn_tracefs(struct dentry *d_tracer)
 {
 
 	trace_create_file("available_filter_functions", 0444,
@@ -4998,7 +4998,7 @@
 }
 core_initcall(ftrace_nodyn_init);
 
-static inline int ftrace_init_dyn_debugfs(struct dentry *d_tracer) { return 0; }
+static inline int ftrace_init_dyn_tracefs(struct dentry *d_tracer) { return 0; }
 static inline void ftrace_startup_enable(int command) { }
 static inline void ftrace_startup_all(int command) { }
 /* Keep as macros so we do not need to define the commands */
@@ -5451,7 +5451,7 @@
 	.release	= ftrace_pid_release,
 };
 
-static __init int ftrace_init_debugfs(void)
+static __init int ftrace_init_tracefs(void)
 {
 	struct dentry *d_tracer;
 
@@ -5459,16 +5459,16 @@
 	if (IS_ERR(d_tracer))
 		return 0;
 
-	ftrace_init_dyn_debugfs(d_tracer);
+	ftrace_init_dyn_tracefs(d_tracer);
 
 	trace_create_file("set_ftrace_pid", 0644, d_tracer,
 			    NULL, &ftrace_pid_fops);
 
-	ftrace_profile_debugfs(d_tracer);
+	ftrace_profile_tracefs(d_tracer);
 
 	return 0;
 }
-fs_initcall(ftrace_init_debugfs);
+fs_initcall(ftrace_init_tracefs);
 
 /**
  * ftrace_kill - kill ftrace