tracing: Merge struct event_trigger_ops into struct event_command

Now that there's pretty much a one to one mapping between the struct
event_trigger_ops and struct event_command, there's no reason to have two
different structures. Merge the function pointers of event_trigger_ops
into event_command.

There's one exception in trace_events_hist.c for the
event_hist_trigger_named_ops. This has special logic for the init and free
function pointers for "named histograms". In this case, allocate the
cmd_ops of the event_trigger_data and set it to the proper init and free
functions, which are used to initialize and free the event_trigger_data
respectively. Have the free function and the init function (on failure)
free the cmd_ops of the data element.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://patch.msgid.link/20251125200932.446322765@kernel.org
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

1 files changed, 48 insertions, 45 deletions

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index f9cc8d6a215b..f0dafc1f2787 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -5694,7 +5694,7 @@ static void hist_trigger_show(struct seq_file *m,
 		seq_puts(m, "\n\n");
 
 	seq_puts(m, "# event histogram\n#\n# trigger info: ");
-	data->ops->print(m, data);
+	data->cmd_ops->print(m, data);
 	seq_puts(m, "#\n\n");
 
 	hist_data = data->private_data;
@@ -6016,7 +6016,7 @@ static void hist_trigger_debug_show(struct seq_file *m,
 		seq_puts(m, "\n\n");
 
 	seq_puts(m, "# event histogram\n#\n# trigger info: ");
-	data->ops->print(m, data);
+	data->cmd_ops->print(m, data);
 	seq_puts(m, "#\n\n");
 
 	hist_data = data->private_data;
@@ -6326,20 +6326,21 @@ static void event_hist_trigger_free(struct event_trigger_data *data)
 	free_hist_pad();
 }
 
-static const struct event_trigger_ops event_hist_trigger_ops = {
-	.trigger		= event_hist_trigger,
-	.print			= event_hist_trigger_print,
-	.init			= event_hist_trigger_init,
-	.free			= event_hist_trigger_free,
-};
-
 static int event_hist_trigger_named_init(struct event_trigger_data *data)
 {
+	int ret;
+
 	data->ref++;
 
 	save_named_trigger(data->named_data->name, data);
 
-	return event_hist_trigger_init(data->named_data);
+	ret = event_hist_trigger_init(data->named_data);
+	if (ret < 0) {
+		kfree(data->cmd_ops);
+		data->cmd_ops = &trigger_hist_cmd;
+	}
+
+	return ret;
 }
 
 static void event_hist_trigger_named_free(struct event_trigger_data *data)
@@ -6351,18 +6352,14 @@ static void event_hist_trigger_named_free(struct event_trigger_data *data)
 
 	data->ref--;
 	if (!data->ref) {
+		struct event_command *cmd_ops = data->cmd_ops;
+
 		del_named_trigger(data);
 		trigger_data_free(data);
+		kfree(cmd_ops);
 	}
 }
 
-static const struct event_trigger_ops event_hist_trigger_named_ops = {
-	.trigger		= event_hist_trigger,
-	.print			= event_hist_trigger_print,
-	.init			= event_hist_trigger_named_init,
-	.free			= event_hist_trigger_named_free,
-};
-
 static void hist_clear(struct event_trigger_data *data)
 {
 	struct hist_trigger_data *hist_data = data->private_data;
@@ -6556,13 +6553,24 @@ static int hist_register_trigger(char *glob,
 		data->paused = true;
 
 	if (named_data) {
+		struct event_command *cmd_ops;
+
 		data->private_data = named_data->private_data;
 		set_named_trigger_data(data, named_data);
-		data->ops = &event_hist_trigger_named_ops;
+		/* Copy the command ops and update some of the functions */
+		cmd_ops = kmalloc(sizeof(*cmd_ops), GFP_KERNEL);
+		if (!cmd_ops) {
+			ret = -ENOMEM;
+			goto out;
+		}
+		*cmd_ops = *data->cmd_ops;
+		cmd_ops->init = event_hist_trigger_named_init;
+		cmd_ops->free = event_hist_trigger_named_free;
+		data->cmd_ops = cmd_ops;
 	}
 
-	if (data->ops->init) {
-		ret = data->ops->init(data);
+	if (data->cmd_ops->init) {
+		ret = data->cmd_ops->init(data);
 		if (ret < 0)
 			goto out;
 	}
@@ -6676,8 +6684,8 @@ static void hist_unregister_trigger(char *glob,
 		}
 	}
 
-	if (test && test->ops->free)
-		test->ops->free(test);
+	if (test && test->cmd_ops->free)
+		test->cmd_ops->free(test);
 
 	if (hist_data->enable_timestamps) {
 		if (!hist_data->remove || test)
@@ -6729,8 +6737,8 @@ static void hist_unreg_all(struct trace_event_file *file)
 			update_cond_flag(file);
 			if (hist_data->enable_timestamps)
 				tracing_set_filter_buffering(file->tr, false);
-			if (test->ops->free)
-				test->ops->free(test);
+			if (test->cmd_ops->free)
+				test->cmd_ops->free(test);
 		}
 	}
 }
@@ -6902,12 +6910,15 @@ static struct event_command trigger_hist_cmd = {
 	.name			= "hist",
 	.trigger_type		= ETT_EVENT_HIST,
 	.flags			= EVENT_CMD_FL_NEEDS_REC,
-	.trigger_ops		= &event_hist_trigger_ops,
 	.parse			= event_hist_trigger_parse,
 	.reg			= hist_register_trigger,
 	.unreg			= hist_unregister_trigger,
 	.unreg_all		= hist_unreg_all,
 	.set_filter		= set_trigger_filter,
+	.trigger		= event_hist_trigger,
+	.print			= event_hist_trigger_print,
+	.init			= event_hist_trigger_init,
+	.free			= event_hist_trigger_free,
 };
 
 __init int register_trigger_hist_cmd(void)
@@ -6939,22 +6950,6 @@ hist_enable_trigger(struct event_trigger_data *data,
 	}
 }
 
-static const struct event_trigger_ops hist_enable_trigger_ops = {
-	.trigger		= hist_enable_trigger,
-	.count_func		= event_trigger_count,
-	.print			= event_enable_trigger_print,
-	.init			= event_trigger_init,
-	.free			= event_enable_trigger_free,
-};
-
-static const struct event_trigger_ops hist_disable_trigger_ops = {
-	.trigger		= hist_enable_trigger,
-	.count_func		= event_trigger_count,
-	.print			= event_enable_trigger_print,
-	.init			= event_trigger_init,
-	.free			= event_enable_trigger_free,
-};
-
 static void hist_enable_unreg_all(struct trace_event_file *file)
 {
 	struct event_trigger_data *test, *n;
@@ -6964,8 +6959,8 @@ static void hist_enable_unreg_all(struct trace_event_file *file)
 			list_del_rcu(&test->list);
 			update_cond_flag(file);
 			trace_event_trigger_enable_disable(file, 0);
-			if (test->ops->free)
-				test->ops->free(test);
+			if (test->cmd_ops->free)
+				test->cmd_ops->free(test);
 		}
 	}
 }
@@ -6973,23 +6968,31 @@ static void hist_enable_unreg_all(struct trace_event_file *file)
 static struct event_command trigger_hist_enable_cmd = {
 	.name			= ENABLE_HIST_STR,
 	.trigger_type		= ETT_HIST_ENABLE,
-	.trigger_ops		= &hist_enable_trigger_ops,
 	.parse			= event_enable_trigger_parse,
 	.reg			= event_enable_register_trigger,
 	.unreg			= event_enable_unregister_trigger,
 	.unreg_all		= hist_enable_unreg_all,
 	.set_filter		= set_trigger_filter,
+	.trigger		= hist_enable_trigger,
+	.count_func		= event_trigger_count,
+	.print			= event_enable_trigger_print,
+	.init			= event_trigger_init,
+	.free			= event_enable_trigger_free,
 };
 
 static struct event_command trigger_hist_disable_cmd = {
 	.name			= DISABLE_HIST_STR,
 	.trigger_type		= ETT_HIST_ENABLE,
-	.trigger_ops		= &hist_disable_trigger_ops,
 	.parse			= event_enable_trigger_parse,
 	.reg			= event_enable_register_trigger,
 	.unreg			= event_enable_unregister_trigger,
 	.unreg_all		= hist_enable_unreg_all,
 	.set_filter		= set_trigger_filter,
+	.trigger		= hist_enable_trigger,
+	.count_func		= event_trigger_count,
+	.print			= event_enable_trigger_print,
+	.init			= event_trigger_init,
+	.free			= event_enable_trigger_free,
 };
 
 static __init void unregister_trigger_hist_enable_disable_cmds(void)