[PATCH v4] kernel/trace: fixed static warnings

[PATCH v4] kernel/trace: fixed static warnings

[abhijithsriram95]

From: Abhijith Sriram <abhijithsriram95@gmail.com>

The change in the function argument description
was due to the static code checker script reading
the word filter back to back

Changes in v2:
- corrected *m = file->private_data to m = file->private_data

Changes in v3:
- reverted the changes for struct seq_file *m and
  added a new empty line instead

Changes in v4:
- added a new empty line before char *buf ...
  previously this line was relocated to avoid the
  static check warning.

Signed-off-by: Abhijith Sriram <abhijithsriram95@gmail.com>
---
 kernel/trace/trace_events_trigger.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
index 655db2e82513..664283bcd9ea 100644
--- a/kernel/trace/trace_events_trigger.c
+++ b/kernel/trace/trace_events_trigger.c
@@ -246,7 +246,7 @@ event_triggers_post_call(struct trace_event_file *file,
 }
 EXPORT_SYMBOL_GPL(event_triggers_post_call);
 
-#define SHOW_AVAILABLE_TRIGGERS	(void *)(1UL)
+#define SHOW_AVAILABLE_TRIGGERS	((void *)(1UL))
 
 static void *trigger_next(struct seq_file *m, void *t, loff_t *pos)
 {
@@ -352,6 +352,7 @@ static int event_trigger_regex_open(struct inode *inode, struct file *file)
 		ret = seq_open(file, &event_triggers_seq_ops);
 		if (!ret) {
 			struct seq_file *m = file->private_data;
+
 			m->private = file;
 		}
 	}
@@ -390,6 +391,7 @@ static ssize_t event_trigger_regex_write(struct file *file,
 {
 	struct trace_event_file *event_file;
 	ssize_t ret;
+
 	char *buf __free(kfree) = NULL;
 
 	if (!cnt)
@@ -633,6 +635,7 @@ clear_event_triggers(struct trace_array *tr)
 
 	list_for_each_entry(file, &tr->events, list) {
 		struct event_trigger_data *data, *n;
+
 		list_for_each_entry_safe(data, n, &file->triggers, list) {
 			trace_event_trigger_enable_disable(file, 0);
 			list_del_rcu(&data->list);
@@ -785,7 +788,7 @@ static void unregister_trigger(char *glob,
  *   cmd               - the trigger command name
  *   glob              - the trigger command name optionally prefaced with '!'
  *   param_and_filter  - text following cmd and ':'
- *   param             - text following cmd and ':' and stripped of filter
+ *   param             - text following cmd and ':' and filter removed
  *   filter            - the optional filter text following (and including) 'if'
  *
  * To illustrate the use of these components, here are some concrete
-- 
2.43.0

Re: [PATCH v4] kernel/trace: fixed static warnings

[Steven Rostedt]

Subject should be:

 tracing: Fixed static checker warnings

On Mon,  6 Apr 2026 09:28:34 +0200
abhijithsriram95@gmail.com wrote:

> From: Abhijith Sriram <abhijithsriram95@gmail.com>
> 
> The change in the function argument description
> was due to the static code checker script reading
> the word filter back to back
> 

The below changes should be beneath the '---'

> Changes in v2:

The last change should be first. In fact, I only care about the last change
as the previous versions should have the description of what changed.

> - corrected *m = file->private_data to m = file->private_data
> 
> Changes in v3:
> - reverted the changes for struct seq_file *m and
>   added a new empty line instead
> 
> Changes in v4:

That said, this should really be:

 Changes since v3: https://lore.kernel.org/all/20260406060046.223496-2-abhijithsriram95@gmail.com/


> - added a new empty line before char *buf ...
>   previously this line was relocated to avoid the
>   static check warning.
> 
> Signed-off-by: Abhijith Sriram <abhijithsriram95@gmail.com>
> ---
>  kernel/trace/trace_events_trigger.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
> index 655db2e82513..664283bcd9ea 100644
> --- a/kernel/trace/trace_events_trigger.c
> +++ b/kernel/trace/trace_events_trigger.c
> @@ -246,7 +246,7 @@ event_triggers_post_call(struct trace_event_file *file,
>  }
>  EXPORT_SYMBOL_GPL(event_triggers_post_call);
>  
> -#define SHOW_AVAILABLE_TRIGGERS	(void *)(1UL)
> +#define SHOW_AVAILABLE_TRIGGERS	((void *)(1UL))
>  
>  static void *trigger_next(struct seq_file *m, void *t, loff_t *pos)
>  {
> @@ -352,6 +352,7 @@ static int event_trigger_regex_open(struct inode *inode, struct file *file)
>  		ret = seq_open(file, &event_triggers_seq_ops);
>  		if (!ret) {
>  			struct seq_file *m = file->private_data;
> +

This blank line makes the code look worse. Yes, we usually want a blank
line between the variable declarations and the code, but when it comes to
code blocks (not functions) that rule is not as strict.

Get rid of this newline.


>  			m->private = file;
>  		}
>  	}
> @@ -390,6 +391,7 @@ static ssize_t event_trigger_regex_write(struct file *file,
>  {
>  	struct trace_event_file *event_file;
>  	ssize_t ret;
> +
>  	char *buf __free(kfree) = NULL;

The char *buf is a declaration. It no new line is expected before it.

>  
>  	if (!cnt)
> @@ -633,6 +635,7 @@ clear_event_triggers(struct trace_array *tr)
>  
>  	list_for_each_entry(file, &tr->events, list) {
>  		struct event_trigger_data *data, *n;
> +

Again, if it's in a code block, don't change it.

-- Steve

>  		list_for_each_entry_safe(data, n, &file->triggers, list) {
>  			trace_event_trigger_enable_disable(file, 0);
>  			list_del_rcu(&data->list);
> @@ -785,7 +788,7 @@ static void unregister_trigger(char *glob,
>   *   cmd               - the trigger command name
>   *   glob              - the trigger command name optionally prefaced with '!'
>   *   param_and_filter  - text following cmd and ':'
> - *   param             - text following cmd and ':' and stripped of filter
> + *   param             - text following cmd and ':' and filter removed
>   *   filter            - the optional filter text following (and including) 'if'
>   *
>   * To illustrate the use of these components, here are some concrete

Re: [PATCH v4] kernel/trace: fixed static warnings

[Abhijith Sriram]

On Wed, Apr 8, 2026 at 10:23 PM Steven Rostedt <rostedt@goodmis.org> wrote:
>
>
> Subject should be:
>
>  tracing: Fixed static checker warnings
>
> On Mon,  6 Apr 2026 09:28:34 +0200
> abhijithsriram95@gmail.com wrote:
>
> > From: Abhijith Sriram <abhijithsriram95@gmail.com>
> >
> > The change in the function argument description
> > was due to the static code checker script reading
> > the word filter back to back
> >
>
> The below changes should be beneath the '---'
>
> > Changes in v2:
>
> The last change should be first. In fact, I only care about the last change
> as the previous versions should have the description of what changed.
>
> > - corrected *m = file->private_data to m = file->private_data
> >
> > Changes in v3:
> > - reverted the changes for struct seq_file *m and
> >   added a new empty line instead
> >
> > Changes in v4:
>
> That said, this should really be:
>
>  Changes since v3: https://lore.kernel.org/all/20260406060046.223496-2-abhijithsriram95@gmail.com/
>
>
> > - added a new empty line before char *buf ...
> >   previously this line was relocated to avoid the
> >   static check warning.
> >
> > Signed-off-by: Abhijith Sriram <abhijithsriram95@gmail.com>
> > ---
> >  kernel/trace/trace_events_trigger.c | 7 +++++--
> >  1 file changed, 5 insertions(+), 2 deletions(-)
> >
> > diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c
> > index 655db2e82513..664283bcd9ea 100644
> > --- a/kernel/trace/trace_events_trigger.c
> > +++ b/kernel/trace/trace_events_trigger.c
> > @@ -246,7 +246,7 @@ event_triggers_post_call(struct trace_event_file *file,
> >  }
> >  EXPORT_SYMBOL_GPL(event_triggers_post_call);
> >
> > -#define SHOW_AVAILABLE_TRIGGERS      (void *)(1UL)
> > +#define SHOW_AVAILABLE_TRIGGERS      ((void *)(1UL))
> >
> >  static void *trigger_next(struct seq_file *m, void *t, loff_t *pos)
> >  {
> > @@ -352,6 +352,7 @@ static int event_trigger_regex_open(struct inode *inode, struct file *file)
> >               ret = seq_open(file, &event_triggers_seq_ops);
> >               if (!ret) {
> >                       struct seq_file *m = file->private_data;
> > +
>
> This blank line makes the code look worse. Yes, we usually want a blank
> line between the variable declarations and the code, but when it comes to
> code blocks (not functions) that rule is not as strict.
>
> Get rid of this newline.
>
>
> >                       m->private = file;
> >               }
> >       }
> > @@ -390,6 +391,7 @@ static ssize_t event_trigger_regex_write(struct file *file,
> >  {
> >       struct trace_event_file *event_file;
> >       ssize_t ret;
> > +
> >       char *buf __free(kfree) = NULL;
>
> The char *buf is a declaration. It no new line is expected before it.
>
> >
> >       if (!cnt)
> > @@ -633,6 +635,7 @@ clear_event_triggers(struct trace_array *tr)
> >
> >       list_for_each_entry(file, &tr->events, list) {
> >               struct event_trigger_data *data, *n;
> > +
>
> Again, if it's in a code block, don't change it.
>
> -- Steve
>
> >               list_for_each_entry_safe(data, n, &file->triggers, list) {
> >                       trace_event_trigger_enable_disable(file, 0);
> >                       list_del_rcu(&data->list);
> > @@ -785,7 +788,7 @@ static void unregister_trigger(char *glob,
> >   *   cmd               - the trigger command name
> >   *   glob              - the trigger command name optionally prefaced with '!'
> >   *   param_and_filter  - text following cmd and ':'
> > - *   param             - text following cmd and ':' and stripped of filter
> > + *   param             - text following cmd and ':' and filter removed
> >   *   filter            - the optional filter text following (and including) 'if'
> >   *
> >   * To illustrate the use of these components, here are some concrete
>

Shall we totally scrap these changes? Apart from introducing new lines
the only other
changes are to add some brackets and reframe the comments. We are not adding
a lot of value from this change. I will take this as a positive first
time experience
into linux kernel dev and focus on other meaningful changes.

-- 
Regards
Abhijith Sriram