2 files changed, 59 insertions, 7 deletions

diff --git a/tools/lib/traceevent/event-parse.h b/tools/lib/traceevent/event-parse.h
index 8bd7c6a4cbd7..8ca1b8ee50da 100644
--- a/tools/lib/traceevent/event-parse.h
+++ b/tools/lib/traceevent/event-parse.h
@@ -116,7 +116,7 @@ struct pevent_plugin_option {
 	char				*name;
 	char				*plugin_alias;
 	char				*description;
-	char				*value;
+	const char			*value;
 	void				*priv;
 	int				set;
 };
@@ -154,6 +154,10 @@ struct pevent_plugin_option {
  *   .plugin_alias is used to give a shorter name to access
  *   the vairable. Useful if a plugin handles more than one event.
  *
+ *   If .value is not set, then it is considered a boolean and only
+ *   .set will be processed. If .value is defined, then it is considered
+ *   a string option and .set will be ignored.
+ *
  * PEVENT_PLUGIN_ALIAS: (optional)
  *   The name to use for finding options (uses filename if not defined)
  */
diff --git a/tools/lib/traceevent/event-plugin.c b/tools/lib/traceevent/event-plugin.c
index 136162c03af1..a16756ae3526 100644
--- a/tools/lib/traceevent/event-plugin.c
+++ b/tools/lib/traceevent/event-plugin.c
@@ -18,6 +18,7 @@
  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  */
 
+#include <ctype.h>
 #include <stdio.h>
 #include <string.h>
 #include <dlfcn.h>
@@ -49,6 +50,52 @@ struct plugin_list {
 	void			*handle;
 };
 
+static void lower_case(char *str)
+{
+	if (!str)
+		return;
+	for (; *str; str++)
+		*str = tolower(*str);
+}
+
+static int update_option_value(struct pevent_plugin_option *op, const char *val)
+{
+	char *op_val;
+
+	if (!val) {
+		/* toggle, only if option is boolean */
+		if (op->value)
+			/* Warn? */
+			return 0;
+		op->set ^= 1;
+		return 0;
+	}
+
+	/*
+	 * If the option has a value then it takes a string
+	 * otherwise the option is a boolean.
+	 */
+	if (op->value) {
+		op->value = val;
+		return 0;
+	}
+
+	/* Option is boolean, must be either "1", "0", "true" or "false" */
+
+	op_val = strdup(val);
+	if (!op_val)
+		return -1;
+	lower_case(op_val);
+
+	if (strcmp(val, "1") == 0 || strcmp(val, "true") == 0)
+		op->set = 1;
+	else if (strcmp(val, "0") == 0 || strcmp(val, "false") == 0)
+		op->set = 0;
+	free(op_val);
+
+	return 0;
+}
+
 /**
  * traceevent_plugin_list_options - get list of plugin options
  *
@@ -120,6 +167,7 @@ update_option(const char *file, struct pevent_plugin_option *option)
 {
 	struct trace_plugin_options *op;
 	char *plugin;
+	int ret = 0;
 
 	if (option->plugin_alias) {
 		plugin = strdup(option->plugin_alias);
@@ -144,9 +192,10 @@ update_option(const char *file, struct pevent_plugin_option *option)
 		if (strcmp(op->option, option->name) != 0)
 			continue;
 
-		option->value = op->value;
-		option->set ^= 1;
-		goto out;
+		ret = update_option_value(option, op->value);
+		if (ret)
+			goto out;
+		break;
 	}
 
 	/* first look for unnamed options */
@@ -156,14 +205,13 @@ update_option(const char *file, struct pevent_plugin_option *option)
 		if (strcmp(op->option, option->name) != 0)
 			continue;
 
-		option->value = op->value;
-		option->set ^= 1;
+		ret = update_option_value(option, op->value);
 		break;
 	}
 
  out:
 	free(plugin);
-	return 0;
+	return ret;
 }
 
 /**