-#ifndef _LTTNG_WRAPPER_WRITEBACK_H
-#define _LTTNG_WRAPPER_WRITEBACK_H
-
-/*
+/* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1)
+ *
* wrapper/writeback.h
*
* wrapper around global_dirty_limit read. Using KALLSYMS with KALLSYMS_ALL
* exports this variable to GPL modules.
*
* Copyright (C) 2013 Mentor Graphics Corp.
- *
- * 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; only
- * version 2.1 of the License.
- *
- * 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
*/
+#ifndef _LTTNG_WRAPPER_WRITEBACK_H
+#define _LTTNG_WRAPPER_WRITEBACK_H
+
#include <lttng-kernel-version.h>
#ifdef CONFIG_KALLSYMS_ALL
return 0;
}
}
+
+/*
+ * Canary function to check for 'global_wb_domain' at compile time.
+ *
+ * From 'include/linux/writeback.h':
+ *
+ * extern struct wb_domain global_wb_domain;
+ */
+static inline
+unsigned long __canary__global_wb_domain(void)
+{
+ return global_wb_domain.dirty_limit;
+}
+
#else
static unsigned long *global_dirty_limit_sym;
return 0;
}
}
+
+/*
+ * Canary function to check for 'global_dirty_limit' at compile time.
+ *
+ * From 'include/linux/writeback.h':
+ *
+ * extern unsigned long global_dirty_limit;
+ */
+static inline
+unsigned long __canary__global_dirty_limit(void)
+{
+ return global_dirty_limit;
+}
+
#endif
#else /* CONFIG_KALLSYMS_ALL */