Commit 7eeafbca authored by Steven Rostedt (Red Hat)'s avatar Steven Rostedt (Red Hat) Committed by Steven Rostedt
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tracing: Separate out initializing top level dir from instances 



The top level trace array is treated a little different than the
instances, as it has to deal with more of the general tracing.
The tr->dir is the tracing directory, which is an immutable
dentry, where as the tr->dir of instances are the dentry that
was created, and can be destroyed later. These should have different
functions accessing them.

As only tracing_init_dentry() deals with the top level array, fold
the code for it into that function, and remove the trace_init_dentry_tr()
that was also used by the instances to get their directory dentry.

Add a tracing_get_dentry() to just get the tracing dir entry for
instances as well as the top level array.

Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
parent c6028948

kernel/trace/trace.c

+30 −21
Original line number Diff line number Diff line
@@ -5815,26 +5815,9 @@ static __init int register_snapshot_cmd(void) 
static inline __init int register_snapshot_cmd(void) { return 0; }

#endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */



static struct dentry *tracing_init_dentry_tr(struct trace_array *tr)

static struct dentry *tracing_get_dentry(struct trace_array *tr)

{

	if (tr->dir)

	return tr->dir;



	if (!debugfs_initialized())

		return ERR_PTR(-ENODEV);



	if (tr->flags & TRACE_ARRAY_FL_GLOBAL)

		tr->dir = debugfs_create_dir("tracing", NULL);



	if (!tr->dir)

		pr_warn_once("Could not create debugfs directory 'tracing'\n");



	return tr->dir;

}



struct dentry *tracing_init_dentry(void)

{

	return tracing_init_dentry_tr(&global_trace);

}



static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu)
@@ -5844,7 +5827,7 @@ static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) 
	if (tr->percpu_dir)

		return tr->percpu_dir;



	d_tracer = tracing_init_dentry_tr(tr);

	d_tracer = tracing_get_dentry(tr);

	if (IS_ERR(d_tracer))

		return NULL;
@@ -6047,7 +6030,7 @@ static struct dentry *trace_options_init_dentry(struct trace_array *tr) 
	if (tr->options)

		return tr->options;



	d_tracer = tracing_init_dentry_tr(tr);

	d_tracer = tracing_get_dentry(tr);

	if (IS_ERR(d_tracer))

		return NULL;
@@ -6532,6 +6515,33 @@ init_tracer_debugfs(struct trace_array *tr, struct dentry *d_tracer) 


}



/**

 * tracing_init_dentry - initialize top level trace array

 *

 * This is called when creating files or directories in the tracing

 * directory. It is called via fs_initcall() by any of the boot up code

 * and expects to return the dentry of the top level tracing directory.

 */

struct dentry *tracing_init_dentry(void)

{

	struct trace_array *tr = &global_trace;



	if (tr->dir)

		return tr->dir;



	if (WARN_ON(!debugfs_initialized()))

		return ERR_PTR(-ENODEV);



	tr->dir = debugfs_create_dir("tracing", NULL);



	if (!tr->dir) {

		pr_warn_once("Could not create debugfs directory 'tracing'\n");

		return ERR_PTR(-ENOMEM);

	}



	return tr->dir;

}



static __init int tracer_init_debugfs(void)

{

	struct dentry *d_tracer;
@@ -6772,7 +6782,6 @@ __init static int tracer_alloc_buffers(void) 
	int ring_buf_size;

	int ret = -ENOMEM;





	if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL))

		goto out;

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