tracing: Use refcount for trace_event_file reference counter

Instead of using an atomic counter for the trace_event_file reference
counter, use the refcount interface. It has various checks to make sure
the reference counting is correct, and will warn if it detects an error
(like refcount_inc() on '0').

Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20240726144208.687cce24@rorschach.local.home
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt 2024-07-26 14:42:08 -04:00 committed by Steven Rostedt (Google)
parent b156040869
commit 6e2fdceffd
2 changed files with 5 additions and 5 deletions

View File

@ -680,7 +680,7 @@ struct trace_event_file {
* caching and such. Which is mostly OK ;-)
*/
unsigned long flags;
atomic_t ref; /* ref count for opened files */
refcount_t ref; /* ref count for opened files */
atomic_t sm_ref; /* soft-mode reference counter */
atomic_t tm_ref; /* trigger-mode reference counter */
};

View File

@ -992,18 +992,18 @@ static void remove_subsystem(struct trace_subsystem_dir *dir)
void event_file_get(struct trace_event_file *file)
{
atomic_inc(&file->ref);
refcount_inc(&file->ref);
}
void event_file_put(struct trace_event_file *file)
{
if (WARN_ON_ONCE(!atomic_read(&file->ref))) {
if (WARN_ON_ONCE(!refcount_read(&file->ref))) {
if (file->flags & EVENT_FILE_FL_FREED)
kmem_cache_free(file_cachep, file);
return;
}
if (atomic_dec_and_test(&file->ref)) {
if (refcount_dec_and_test(&file->ref)) {
/* Count should only go to zero when it is freed */
if (WARN_ON_ONCE(!(file->flags & EVENT_FILE_FL_FREED)))
return;
@ -3003,7 +3003,7 @@ trace_create_new_event(struct trace_event_call *call,
atomic_set(&file->tm_ref, 0);
INIT_LIST_HEAD(&file->triggers);
list_add(&file->list, &tr->events);
event_file_get(file);
refcount_set(&file->ref, 1);
return file;
}