Index: kernel/generic/src/sysinfo/stats.c
===================================================================
--- kernel/generic/src/sysinfo/stats.c	(revision 3d23553d7329335f0463b75dd6ec3d861c473676)
+++ kernel/generic/src/sysinfo/stats.c	(revision 5869ce0ca5fd1906d3f917cf2a38b5a804b18b9d)
@@ -451,4 +451,5 @@
  * @param name    Task ID (string-encoded number).
  * @param dry_run Do not get the data, just calculate the size.
+ * @param data    Unused.
  *
  * @return Sysinfo return holder. The type of the returned
@@ -460,5 +461,6 @@
  *
  */
-static sysinfo_return_t get_stats_task(const char *name, bool dry_run)
+static sysinfo_return_t get_stats_task(const char *name, bool dry_run,
+    void *data)
 {
 	/* Initially no return value */
@@ -520,4 +522,5 @@
  * @param name    Thread ID (string-encoded number).
  * @param dry_run Do not get the data, just calculate the size.
+ * @param data    Unused.
  *
  * @return Sysinfo return holder. The type of the returned
@@ -529,5 +532,6 @@
  *
  */
-static sysinfo_return_t get_stats_thread(const char *name, bool dry_run)
+static sysinfo_return_t get_stats_thread(const char *name, bool dry_run,
+    void *data)
 {
 	/* Initially no return value */
@@ -634,4 +638,5 @@
  * @param name    Exception number (string-encoded number).
  * @param dry_run Do not get the data, just calculate the size.
+ * @param data    Unused.
  *
  * @return Sysinfo return holder. The type of the returned
@@ -643,5 +648,6 @@
  *
  */
-static sysinfo_return_t get_stats_exception(const char *name, bool dry_run)
+static sysinfo_return_t get_stats_exception(const char *name, bool dry_run,
+    void *data)
 {
 	/* Initially no return value */
@@ -817,7 +823,7 @@
 	sysinfo_set_item_fn_data("system.threads", NULL, get_stats_threads);
 	sysinfo_set_item_fn_data("system.exceptions", NULL, get_stats_exceptions);
-	sysinfo_set_subtree_fn("system.tasks", NULL, get_stats_task);
-	sysinfo_set_subtree_fn("system.threads", NULL, get_stats_thread);
-	sysinfo_set_subtree_fn("system.exceptions", NULL, get_stats_exception);
+	sysinfo_set_subtree_fn("system.tasks", NULL, get_stats_task, NULL);
+	sysinfo_set_subtree_fn("system.threads", NULL, get_stats_thread, NULL);
+	sysinfo_set_subtree_fn("system.exceptions", NULL, get_stats_exception, NULL);
 }
 
Index: kernel/generic/src/sysinfo/sysinfo.c
===================================================================
--- kernel/generic/src/sysinfo/sysinfo.c	(revision 3d23553d7329335f0463b75dd6ec3d861c473676)
+++ kernel/generic/src/sysinfo/sysinfo.c	(revision 5869ce0ca5fd1906d3f917cf2a38b5a804b18b9d)
@@ -151,5 +151,6 @@
 			case SYSINFO_SUBTREE_FUNCTION:
 				/* Get generated data */
-				**ret = cur->subtree.get_data(name + i + 1, dry_run);
+				**ret = cur->subtree.generator.fn(name + i + 1, dry_run,
+				    cur->subtree.generator.data);
 				return NULL;
 			default:
@@ -431,8 +432,9 @@
  *             a new root item (NULL for global sysinfo root).
  * @param fn   Subtree generator function.
+ * @param data Private data to be passed to the generator.
  *
  */
 void sysinfo_set_subtree_fn(const char *name, sysinfo_item_t **root,
-    sysinfo_fn_subtree_t fn)
+    sysinfo_fn_subtree_t fn, void *data)
 {
 	/* Protect sysinfo tree consistency */
@@ -448,5 +450,6 @@
 	if ((item != NULL) && (item->subtree_type != SYSINFO_SUBTREE_TABLE)) {
 		item->subtree_type = SYSINFO_SUBTREE_FUNCTION;
-		item->subtree.get_data = fn;
+		item->subtree.generator.fn = fn;
+		item->subtree.generator.data = data;
 	}