[PATCH v3] tracing: Use trace_create_file() to simplify creation of tracefs entries

Yuntao Wang posted 1 patch 4 years, 5 months ago
kernel/trace/ftrace.c                 |  9 +++------
kernel/trace/trace_dynevent.c         |  9 ++-------
kernel/trace/trace_events.c           | 29 +++++++++------------------
kernel/trace/trace_kprobe.c           | 15 ++++----------
kernel/trace/trace_recursion_record.c |  7 ++-----
5 files changed, 21 insertions(+), 48 deletions(-)
[PATCH v3] tracing: Use trace_create_file() to simplify creation of tracefs entries
Posted by Yuntao Wang 4 years, 5 months ago
Creating tracefs entries with tracefs_create_file() followed by pr_warn()
is tedious and repetitive, we can use trace_create_file() to simplify
this process and make the code more readable.

Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
---
Changes since v1:
- Remove format change updates

Changes since v2:
- Remove unused variables

 kernel/trace/ftrace.c                 |  9 +++------
 kernel/trace/trace_dynevent.c         |  9 ++-------
 kernel/trace/trace_events.c           | 29 +++++++++------------------
 kernel/trace/trace_kprobe.c           | 15 ++++----------
 kernel/trace/trace_recursion_record.c |  7 ++-----
 5 files changed, 21 insertions(+), 48 deletions(-)

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 403e485bf091..6d9bb73d19d3 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -952,7 +952,6 @@ static struct tracer_stat function_stats __initdata = {
 static __init void ftrace_profile_tracefs(struct dentry *d_tracer)
 {
 	struct ftrace_profile_stat *stat;
-	struct dentry *entry;
 	char *name;
 	int ret;
 	int cpu;
@@ -983,11 +982,9 @@ static __init void ftrace_profile_tracefs(struct dentry *d_tracer)
 		}
 	}
 
-	entry = tracefs_create_file("function_profile_enabled",
-				    TRACE_MODE_WRITE, d_tracer, NULL,
-				    &ftrace_profile_fops);
-	if (!entry)
-		pr_warn("Could not create tracefs 'function_profile_enabled' entry\n");
+	trace_create_file("function_profile_enabled",
+			  TRACE_MODE_WRITE, d_tracer, NULL,
+			  &ftrace_profile_fops);
 }
 
 #else /* CONFIG_FUNCTION_PROFILER */
diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c
index e34e8182ee4b..076b447a1b88 100644
--- a/kernel/trace/trace_dynevent.c
+++ b/kernel/trace/trace_dynevent.c
@@ -255,19 +255,14 @@ static const struct file_operations dynamic_events_ops = {
 /* Make a tracefs interface for controlling dynamic events */
 static __init int init_dynamic_event(void)
 {
-	struct dentry *entry;
 	int ret;
 
 	ret = tracing_init_dentry();
 	if (ret)
 		return 0;
 
-	entry = tracefs_create_file("dynamic_events", TRACE_MODE_WRITE, NULL,
-				    NULL, &dynamic_events_ops);
-
-	/* Event list interface */
-	if (!entry)
-		pr_warn("Could not create tracefs 'dynamic_events' entry\n");
+	trace_create_file("dynamic_events", TRACE_MODE_WRITE, NULL,
+			  NULL, &dynamic_events_ops);
 
 	return 0;
 }
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 3147614c1812..718518b3c491 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -3446,12 +3446,10 @@ create_event_toplevel_files(struct dentry *parent, struct trace_array *tr)
 	struct dentry *d_events;
 	struct dentry *entry;
 
-	entry = tracefs_create_file("set_event", TRACE_MODE_WRITE, parent,
-				    tr, &ftrace_set_event_fops);
-	if (!entry) {
-		pr_warn("Could not create tracefs 'set_event' entry\n");
+	entry = trace_create_file("set_event", TRACE_MODE_WRITE, parent,
+				  tr, &ftrace_set_event_fops);
+	if (!entry)
 		return -ENOMEM;
-	}
 
 	d_events = tracefs_create_dir("events", parent);
 	if (!d_events) {
@@ -3466,16 +3464,12 @@ create_event_toplevel_files(struct dentry *parent, struct trace_array *tr)
 
 	/* There are not as crucial, just warn if they are not created */
 
-	entry = tracefs_create_file("set_event_pid", TRACE_MODE_WRITE, parent,
-				    tr, &ftrace_set_event_pid_fops);
-	if (!entry)
-		pr_warn("Could not create tracefs 'set_event_pid' entry\n");
+	trace_create_file("set_event_pid", TRACE_MODE_WRITE, parent,
+			  tr, &ftrace_set_event_pid_fops);
 
-	entry = tracefs_create_file("set_event_notrace_pid",
-				    TRACE_MODE_WRITE, parent, tr,
-				    &ftrace_set_event_notrace_pid_fops);
-	if (!entry)
-		pr_warn("Could not create tracefs 'set_event_notrace_pid' entry\n");
+	trace_create_file("set_event_notrace_pid",
+			  TRACE_MODE_WRITE, parent, tr,
+			  &ftrace_set_event_notrace_pid_fops);
 
 	/* ring buffer internal formats */
 	trace_create_file("header_page", TRACE_MODE_READ, d_events,
@@ -3690,17 +3684,14 @@ static __init int event_trace_init_fields(void)
 __init int event_trace_init(void)
 {
 	struct trace_array *tr;
-	struct dentry *entry;
 	int ret;
 
 	tr = top_trace_array();
 	if (!tr)
 		return -ENODEV;
 
-	entry = tracefs_create_file("available_events", TRACE_MODE_READ,
-				    NULL, tr, &ftrace_avail_fops);
-	if (!entry)
-		pr_warn("Could not create tracefs 'available_events' entry\n");
+	trace_create_file("available_events", TRACE_MODE_READ,
+			  NULL, tr, &ftrace_avail_fops);
 
 	ret = early_event_add_tracer(NULL, tr);
 	if (ret)
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 3d85323278ed..5c35c2311690 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1906,25 +1906,18 @@ core_initcall(init_kprobe_trace_early);
 static __init int init_kprobe_trace(void)
 {
 	int ret;
-	struct dentry *entry;
 
 	ret = tracing_init_dentry();
 	if (ret)
 		return 0;
 
-	entry = tracefs_create_file("kprobe_events", TRACE_MODE_WRITE,
-				    NULL, NULL, &kprobe_events_ops);
-
 	/* Event list interface */
-	if (!entry)
-		pr_warn("Could not create tracefs 'kprobe_events' entry\n");
+	trace_create_file("kprobe_events", TRACE_MODE_WRITE,
+			  NULL, NULL, &kprobe_events_ops);
 
 	/* Profile interface */
-	entry = tracefs_create_file("kprobe_profile", TRACE_MODE_READ,
-				    NULL, NULL, &kprobe_profile_ops);
-
-	if (!entry)
-		pr_warn("Could not create tracefs 'kprobe_profile' entry\n");
+	trace_create_file("kprobe_profile", TRACE_MODE_READ,
+			  NULL, NULL, &kprobe_profile_ops);
 
 	setup_boot_kprobe_events();
 
diff --git a/kernel/trace/trace_recursion_record.c b/kernel/trace/trace_recursion_record.c
index 4d4b78c8ca25..a520b11afb0d 100644
--- a/kernel/trace/trace_recursion_record.c
+++ b/kernel/trace/trace_recursion_record.c
@@ -224,12 +224,9 @@ static const struct file_operations recursed_functions_fops = {
 
 __init static int create_recursed_functions(void)
 {
-	struct dentry *dentry;
 
-	dentry = trace_create_file("recursed_functions", TRACE_MODE_WRITE,
-				   NULL, NULL, &recursed_functions_fops);
-	if (!dentry)
-		pr_warn("WARNING: Failed to create recursed_functions\n");
+	trace_create_file("recursed_functions", TRACE_MODE_WRITE,
+			  NULL, NULL, &recursed_functions_fops);
 	return 0;
 }
 
-- 
2.34.1

Re: [PATCH v3] tracing: Use trace_create_file() to simplify creation of tracefs entries
Posted by Steven Rostedt 4 years, 1 month ago
On Fri, 14 Jan 2022 21:10:52 +0800
Yuntao Wang <ytcoode@gmail.com> wrote:

> Creating tracefs entries with tracefs_create_file() followed by pr_warn()
> is tedious and repetitive, we can use trace_create_file() to simplify
> this process and make the code more readable.

Sorry I missed this patch (I was in the process of changing jobs when it
was sent out, and I had COVID :-p ). I'll add it to my queue.

Masami, this touches trace_kprobes.c, care to ACK that part?

Thanks,

-- Steve


> 
> Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
> ---
> Changes since v1:
> - Remove format change updates
> 
> Changes since v2:
> - Remove unused variables
> 
>  kernel/trace/ftrace.c                 |  9 +++------
>  kernel/trace/trace_dynevent.c         |  9 ++-------
>  kernel/trace/trace_events.c           | 29 +++++++++------------------
>  kernel/trace/trace_kprobe.c           | 15 ++++----------
>  kernel/trace/trace_recursion_record.c |  7 ++-----
>  5 files changed, 21 insertions(+), 48 deletions(-)
> 
> diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
> index 403e485bf091..6d9bb73d19d3 100644
> --- a/kernel/trace/ftrace.c
> +++ b/kernel/trace/ftrace.c
> @@ -952,7 +952,6 @@ static struct tracer_stat function_stats __initdata = {
>  static __init void ftrace_profile_tracefs(struct dentry *d_tracer)
>  {
>  	struct ftrace_profile_stat *stat;
> -	struct dentry *entry;
>  	char *name;
>  	int ret;
>  	int cpu;
> @@ -983,11 +982,9 @@ static __init void ftrace_profile_tracefs(struct dentry *d_tracer)
>  		}
>  	}
>  
> -	entry = tracefs_create_file("function_profile_enabled",
> -				    TRACE_MODE_WRITE, d_tracer, NULL,
> -				    &ftrace_profile_fops);
> -	if (!entry)
> -		pr_warn("Could not create tracefs 'function_profile_enabled' entry\n");
> +	trace_create_file("function_profile_enabled",
> +			  TRACE_MODE_WRITE, d_tracer, NULL,
> +			  &ftrace_profile_fops);
>  }
>  
>  #else /* CONFIG_FUNCTION_PROFILER */
> diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c
> index e34e8182ee4b..076b447a1b88 100644
> --- a/kernel/trace/trace_dynevent.c
> +++ b/kernel/trace/trace_dynevent.c
> @@ -255,19 +255,14 @@ static const struct file_operations dynamic_events_ops = {
>  /* Make a tracefs interface for controlling dynamic events */
>  static __init int init_dynamic_event(void)
>  {
> -	struct dentry *entry;
>  	int ret;
>  
>  	ret = tracing_init_dentry();
>  	if (ret)
>  		return 0;
>  
> -	entry = tracefs_create_file("dynamic_events", TRACE_MODE_WRITE, NULL,
> -				    NULL, &dynamic_events_ops);
> -
> -	/* Event list interface */
> -	if (!entry)
> -		pr_warn("Could not create tracefs 'dynamic_events' entry\n");
> +	trace_create_file("dynamic_events", TRACE_MODE_WRITE, NULL,
> +			  NULL, &dynamic_events_ops);
>  
>  	return 0;
>  }
> diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
> index 3147614c1812..718518b3c491 100644
> --- a/kernel/trace/trace_events.c
> +++ b/kernel/trace/trace_events.c
> @@ -3446,12 +3446,10 @@ create_event_toplevel_files(struct dentry *parent, struct trace_array *tr)
>  	struct dentry *d_events;
>  	struct dentry *entry;
>  
> -	entry = tracefs_create_file("set_event", TRACE_MODE_WRITE, parent,
> -				    tr, &ftrace_set_event_fops);
> -	if (!entry) {
> -		pr_warn("Could not create tracefs 'set_event' entry\n");
> +	entry = trace_create_file("set_event", TRACE_MODE_WRITE, parent,
> +				  tr, &ftrace_set_event_fops);
> +	if (!entry)
>  		return -ENOMEM;
> -	}
>  
>  	d_events = tracefs_create_dir("events", parent);
>  	if (!d_events) {
> @@ -3466,16 +3464,12 @@ create_event_toplevel_files(struct dentry *parent, struct trace_array *tr)
>  
>  	/* There are not as crucial, just warn if they are not created */
>  
> -	entry = tracefs_create_file("set_event_pid", TRACE_MODE_WRITE, parent,
> -				    tr, &ftrace_set_event_pid_fops);
> -	if (!entry)
> -		pr_warn("Could not create tracefs 'set_event_pid' entry\n");
> +	trace_create_file("set_event_pid", TRACE_MODE_WRITE, parent,
> +			  tr, &ftrace_set_event_pid_fops);
>  
> -	entry = tracefs_create_file("set_event_notrace_pid",
> -				    TRACE_MODE_WRITE, parent, tr,
> -				    &ftrace_set_event_notrace_pid_fops);
> -	if (!entry)
> -		pr_warn("Could not create tracefs 'set_event_notrace_pid' entry\n");
> +	trace_create_file("set_event_notrace_pid",
> +			  TRACE_MODE_WRITE, parent, tr,
> +			  &ftrace_set_event_notrace_pid_fops);
>  
>  	/* ring buffer internal formats */
>  	trace_create_file("header_page", TRACE_MODE_READ, d_events,
> @@ -3690,17 +3684,14 @@ static __init int event_trace_init_fields(void)
>  __init int event_trace_init(void)
>  {
>  	struct trace_array *tr;
> -	struct dentry *entry;
>  	int ret;
>  
>  	tr = top_trace_array();
>  	if (!tr)
>  		return -ENODEV;
>  
> -	entry = tracefs_create_file("available_events", TRACE_MODE_READ,
> -				    NULL, tr, &ftrace_avail_fops);
> -	if (!entry)
> -		pr_warn("Could not create tracefs 'available_events' entry\n");
> +	trace_create_file("available_events", TRACE_MODE_READ,
> +			  NULL, tr, &ftrace_avail_fops);
>  
>  	ret = early_event_add_tracer(NULL, tr);
>  	if (ret)
> diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
> index 3d85323278ed..5c35c2311690 100644
> --- a/kernel/trace/trace_kprobe.c
> +++ b/kernel/trace/trace_kprobe.c
> @@ -1906,25 +1906,18 @@ core_initcall(init_kprobe_trace_early);
>  static __init int init_kprobe_trace(void)
>  {
>  	int ret;
> -	struct dentry *entry;
>  
>  	ret = tracing_init_dentry();
>  	if (ret)
>  		return 0;
>  
> -	entry = tracefs_create_file("kprobe_events", TRACE_MODE_WRITE,
> -				    NULL, NULL, &kprobe_events_ops);
> -
>  	/* Event list interface */
> -	if (!entry)
> -		pr_warn("Could not create tracefs 'kprobe_events' entry\n");
> +	trace_create_file("kprobe_events", TRACE_MODE_WRITE,
> +			  NULL, NULL, &kprobe_events_ops);
>  
>  	/* Profile interface */
> -	entry = tracefs_create_file("kprobe_profile", TRACE_MODE_READ,
> -				    NULL, NULL, &kprobe_profile_ops);
> -
> -	if (!entry)
> -		pr_warn("Could not create tracefs 'kprobe_profile' entry\n");
> +	trace_create_file("kprobe_profile", TRACE_MODE_READ,
> +			  NULL, NULL, &kprobe_profile_ops);
>  
>  	setup_boot_kprobe_events();
>  
> diff --git a/kernel/trace/trace_recursion_record.c b/kernel/trace/trace_recursion_record.c
> index 4d4b78c8ca25..a520b11afb0d 100644
> --- a/kernel/trace/trace_recursion_record.c
> +++ b/kernel/trace/trace_recursion_record.c
> @@ -224,12 +224,9 @@ static const struct file_operations recursed_functions_fops = {
>  
>  __init static int create_recursed_functions(void)
>  {
> -	struct dentry *dentry;
>  
> -	dentry = trace_create_file("recursed_functions", TRACE_MODE_WRITE,
> -				   NULL, NULL, &recursed_functions_fops);
> -	if (!dentry)
> -		pr_warn("WARNING: Failed to create recursed_functions\n");
> +	trace_create_file("recursed_functions", TRACE_MODE_WRITE,
> +			  NULL, NULL, &recursed_functions_fops);
>  	return 0;
>  }
>
Re: [PATCH v3] tracing: Use trace_create_file() to simplify creation of tracefs entries
Posted by Masami Hiramatsu (Google) 4 years, 1 month ago
On Tue, 24 May 2022 12:07:13 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> On Fri, 14 Jan 2022 21:10:52 +0800
> Yuntao Wang <ytcoode@gmail.com> wrote:
> 
> > Creating tracefs entries with tracefs_create_file() followed by pr_warn()
> > is tedious and repetitive, we can use trace_create_file() to simplify
> > this process and make the code more readable.
> 
> Sorry I missed this patch (I was in the process of changing jobs when it
> was sent out, and I had COVID :-p ). I'll add it to my queue.
> 
> Masami, this touches trace_kprobes.c, care to ACK that part?

Yes, trace_kprobes.c part looks good to me.

Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Thank you!

> 
> Thanks,
> 
> -- Steve
> 
> 
> > 
> > Signed-off-by: Yuntao Wang <ytcoode@gmail.com>
> > ---
> > Changes since v1:
> > - Remove format change updates
> > 
> > Changes since v2:
> > - Remove unused variables
> > 
> >  kernel/trace/ftrace.c                 |  9 +++------
> >  kernel/trace/trace_dynevent.c         |  9 ++-------
> >  kernel/trace/trace_events.c           | 29 +++++++++------------------
> >  kernel/trace/trace_kprobe.c           | 15 ++++----------
> >  kernel/trace/trace_recursion_record.c |  7 ++-----
> >  5 files changed, 21 insertions(+), 48 deletions(-)
> > 
> > diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
> > index 403e485bf091..6d9bb73d19d3 100644
> > --- a/kernel/trace/ftrace.c
> > +++ b/kernel/trace/ftrace.c
> > @@ -952,7 +952,6 @@ static struct tracer_stat function_stats __initdata = {
> >  static __init void ftrace_profile_tracefs(struct dentry *d_tracer)
> >  {
> >  	struct ftrace_profile_stat *stat;
> > -	struct dentry *entry;
> >  	char *name;
> >  	int ret;
> >  	int cpu;
> > @@ -983,11 +982,9 @@ static __init void ftrace_profile_tracefs(struct dentry *d_tracer)
> >  		}
> >  	}
> >  
> > -	entry = tracefs_create_file("function_profile_enabled",
> > -				    TRACE_MODE_WRITE, d_tracer, NULL,
> > -				    &ftrace_profile_fops);
> > -	if (!entry)
> > -		pr_warn("Could not create tracefs 'function_profile_enabled' entry\n");
> > +	trace_create_file("function_profile_enabled",
> > +			  TRACE_MODE_WRITE, d_tracer, NULL,
> > +			  &ftrace_profile_fops);
> >  }
> >  
> >  #else /* CONFIG_FUNCTION_PROFILER */
> > diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c
> > index e34e8182ee4b..076b447a1b88 100644
> > --- a/kernel/trace/trace_dynevent.c
> > +++ b/kernel/trace/trace_dynevent.c
> > @@ -255,19 +255,14 @@ static const struct file_operations dynamic_events_ops = {
> >  /* Make a tracefs interface for controlling dynamic events */
> >  static __init int init_dynamic_event(void)
> >  {
> > -	struct dentry *entry;
> >  	int ret;
> >  
> >  	ret = tracing_init_dentry();
> >  	if (ret)
> >  		return 0;
> >  
> > -	entry = tracefs_create_file("dynamic_events", TRACE_MODE_WRITE, NULL,
> > -				    NULL, &dynamic_events_ops);
> > -
> > -	/* Event list interface */
> > -	if (!entry)
> > -		pr_warn("Could not create tracefs 'dynamic_events' entry\n");
> > +	trace_create_file("dynamic_events", TRACE_MODE_WRITE, NULL,
> > +			  NULL, &dynamic_events_ops);
> >  
> >  	return 0;
> >  }
> > diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
> > index 3147614c1812..718518b3c491 100644
> > --- a/kernel/trace/trace_events.c
> > +++ b/kernel/trace/trace_events.c
> > @@ -3446,12 +3446,10 @@ create_event_toplevel_files(struct dentry *parent, struct trace_array *tr)
> >  	struct dentry *d_events;
> >  	struct dentry *entry;
> >  
> > -	entry = tracefs_create_file("set_event", TRACE_MODE_WRITE, parent,
> > -				    tr, &ftrace_set_event_fops);
> > -	if (!entry) {
> > -		pr_warn("Could not create tracefs 'set_event' entry\n");
> > +	entry = trace_create_file("set_event", TRACE_MODE_WRITE, parent,
> > +				  tr, &ftrace_set_event_fops);
> > +	if (!entry)
> >  		return -ENOMEM;
> > -	}
> >  
> >  	d_events = tracefs_create_dir("events", parent);
> >  	if (!d_events) {
> > @@ -3466,16 +3464,12 @@ create_event_toplevel_files(struct dentry *parent, struct trace_array *tr)
> >  
> >  	/* There are not as crucial, just warn if they are not created */
> >  
> > -	entry = tracefs_create_file("set_event_pid", TRACE_MODE_WRITE, parent,
> > -				    tr, &ftrace_set_event_pid_fops);
> > -	if (!entry)
> > -		pr_warn("Could not create tracefs 'set_event_pid' entry\n");
> > +	trace_create_file("set_event_pid", TRACE_MODE_WRITE, parent,
> > +			  tr, &ftrace_set_event_pid_fops);
> >  
> > -	entry = tracefs_create_file("set_event_notrace_pid",
> > -				    TRACE_MODE_WRITE, parent, tr,
> > -				    &ftrace_set_event_notrace_pid_fops);
> > -	if (!entry)
> > -		pr_warn("Could not create tracefs 'set_event_notrace_pid' entry\n");
> > +	trace_create_file("set_event_notrace_pid",
> > +			  TRACE_MODE_WRITE, parent, tr,
> > +			  &ftrace_set_event_notrace_pid_fops);
> >  
> >  	/* ring buffer internal formats */
> >  	trace_create_file("header_page", TRACE_MODE_READ, d_events,
> > @@ -3690,17 +3684,14 @@ static __init int event_trace_init_fields(void)
> >  __init int event_trace_init(void)
> >  {
> >  	struct trace_array *tr;
> > -	struct dentry *entry;
> >  	int ret;
> >  
> >  	tr = top_trace_array();
> >  	if (!tr)
> >  		return -ENODEV;
> >  
> > -	entry = tracefs_create_file("available_events", TRACE_MODE_READ,
> > -				    NULL, tr, &ftrace_avail_fops);
> > -	if (!entry)
> > -		pr_warn("Could not create tracefs 'available_events' entry\n");
> > +	trace_create_file("available_events", TRACE_MODE_READ,
> > +			  NULL, tr, &ftrace_avail_fops);
> >  
> >  	ret = early_event_add_tracer(NULL, tr);
> >  	if (ret)
> > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
> > index 3d85323278ed..5c35c2311690 100644
> > --- a/kernel/trace/trace_kprobe.c
> > +++ b/kernel/trace/trace_kprobe.c
> > @@ -1906,25 +1906,18 @@ core_initcall(init_kprobe_trace_early);
> >  static __init int init_kprobe_trace(void)
> >  {
> >  	int ret;
> > -	struct dentry *entry;
> >  
> >  	ret = tracing_init_dentry();
> >  	if (ret)
> >  		return 0;
> >  
> > -	entry = tracefs_create_file("kprobe_events", TRACE_MODE_WRITE,
> > -				    NULL, NULL, &kprobe_events_ops);
> > -
> >  	/* Event list interface */
> > -	if (!entry)
> > -		pr_warn("Could not create tracefs 'kprobe_events' entry\n");
> > +	trace_create_file("kprobe_events", TRACE_MODE_WRITE,
> > +			  NULL, NULL, &kprobe_events_ops);
> >  
> >  	/* Profile interface */
> > -	entry = tracefs_create_file("kprobe_profile", TRACE_MODE_READ,
> > -				    NULL, NULL, &kprobe_profile_ops);
> > -
> > -	if (!entry)
> > -		pr_warn("Could not create tracefs 'kprobe_profile' entry\n");
> > +	trace_create_file("kprobe_profile", TRACE_MODE_READ,
> > +			  NULL, NULL, &kprobe_profile_ops);
> >  
> >  	setup_boot_kprobe_events();
> >  
> > diff --git a/kernel/trace/trace_recursion_record.c b/kernel/trace/trace_recursion_record.c
> > index 4d4b78c8ca25..a520b11afb0d 100644
> > --- a/kernel/trace/trace_recursion_record.c
> > +++ b/kernel/trace/trace_recursion_record.c
> > @@ -224,12 +224,9 @@ static const struct file_operations recursed_functions_fops = {
> >  
> >  __init static int create_recursed_functions(void)
> >  {
> > -	struct dentry *dentry;
> >  
> > -	dentry = trace_create_file("recursed_functions", TRACE_MODE_WRITE,
> > -				   NULL, NULL, &recursed_functions_fops);
> > -	if (!dentry)
> > -		pr_warn("WARNING: Failed to create recursed_functions\n");
> > +	trace_create_file("recursed_functions", TRACE_MODE_WRITE,
> > +			  NULL, NULL, &recursed_functions_fops);
> >  	return 0;
> >  }
> >  
> 


-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>