Commit 6bba9288 authored by Steven Rostedt (Google)'s avatar Steven Rostedt (Google)
Browse files

tracing: Add free_trace_iter_content() helper function 

As the trace iterator is created and used by various interfaces, the clean
up of it needs to be consistent. Create a free_trace_iter_content() helper
function that frees the content of the iterator and use that to clean it
up in all places that it is used.

Link: https://lkml.kernel.org/r/20230715141348.341887497@goodmis.org



Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
Reviewed-by: default avatarMasami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: default avatarSteven Rostedt (Google) <rostedt@goodmis.org>
parent 9182b519

kernel/trace/trace.c

+22 −11
Original line number Diff line number Diff line
@@ -4799,6 +4799,25 @@ static const struct seq_operations tracer_seq_ops = { 
	.show		= s_show,

};



/*

 * Note, as iter itself can be allocated and freed in different

 * ways, this function is only used to free its content, and not

 * the iterator itself. The only requirement to all the allocations

 * is that it must zero all fields (kzalloc), as freeing works with

 * ethier allocated content or NULL.

 */

static void free_trace_iter_content(struct trace_iterator *iter)

{

	/* The fmt is either NULL, allocated or points to static_fmt_buf */

	if (iter->fmt != static_fmt_buf)

		kfree(iter->fmt);



	kfree(iter->temp);

	kfree(iter->buffer_iter);

	mutex_destroy(&iter->mutex);

	free_cpumask_var(iter->started);

}



static struct trace_iterator *

__tracing_open(struct inode *inode, struct file *file, bool snapshot)

{
@@ -4906,8 +4925,7 @@ __tracing_open(struct inode *inode, struct file *file, bool snapshot) 


 fail:

	mutex_unlock(&trace_types_lock);

	kfree(iter->temp);

	kfree(iter->buffer_iter);

	free_trace_iter_content(iter);

release:

	seq_release_private(inode, file);

	return ERR_PTR(-ENOMEM);
@@ -4986,11 +5004,7 @@ static int tracing_release(struct inode *inode, struct file *file) 


	mutex_unlock(&trace_types_lock);



	mutex_destroy(&iter->mutex);

	free_cpumask_var(iter->started);

	kfree(iter->fmt);

	kfree(iter->temp);

	kfree(iter->buffer_iter);

	free_trace_iter_content(iter);

	seq_release_private(inode, file);



	return 0;
@@ -6747,10 +6761,7 @@ static int tracing_release_pipe(struct inode *inode, struct file *file) 


	mutex_unlock(&trace_types_lock);



	free_cpumask_var(iter->started);

	kfree(iter->fmt);

	kfree(iter->temp);

	mutex_destroy(&iter->mutex);

	free_trace_iter_content(iter);

	kfree(iter);



	trace_array_put(tr);