RCU dereference check if within read-side critical section

[userspace-rcu.git] / urcu-checker.c

diff --git a/urcu-checker.c b/urcu-checker.c
new file mode 100644 (file)
index 0000000..234bd9b
--- /dev/null
+++ b/urcu-checker.c
@@ -0,0 +1,68 @@
+/*
+ * urcu-checker.c
+ *
+ * Userspace RCU library checker
+ *
+ * Copyright (c) 2014 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <string.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <urcu/urcu-checker.h>
+#include <urcu/tls-compat.h>
+
+#define URCU_DEBUG_STACK_LEN   10
+
+struct urcu_debug_entry {
+       void *ip;
+       int depth;
+};
+
+struct urcu_debug_stack {
+       struct urcu_debug_entry stack[URCU_DEBUG_STACK_LEN];
+       int stackend;
+};
+
+static DEFINE_URCU_TLS(struct urcu_debug_stack, rcu_debug_stack);
+
+void rcu_read_lock_debug(void)
+{
+       struct urcu_debug_stack *r = &URCU_TLS(rcu_debug_stack);
+
+       r->stack[r->stackend++].ip = __builtin_return_address(0);
+}
+
+void rcu_read_unlock_debug(void)
+{
+       struct urcu_debug_stack *r = &URCU_TLS(rcu_debug_stack);
+
+       assert(r->stackend != 0);
+       r->stack[--r->stackend].ip = NULL;
+}
+
+void rcu_read_ongoing_check_debug(const char *func)
+{
+       struct urcu_debug_stack *r = &URCU_TLS(rcu_debug_stack);
+
+       if (r->stackend == 0) {
+               fprintf(stderr, "URCU LOCKED CHECK failure: %p\n",
+                       __builtin_return_address(0));
+               abort();
+       }
+}