README.md: cleanup formatting for bullet lists

[lttng-modules.git] / wrapper / kref.h

diff --git a/wrapper/kref.h b/wrapper/kref.h
index eedefbfe87e96ab47ac79ac0c4a36565c03a47ae..f220ddbfaaea098d56f1ebe770408e544390145f 100644 (file)
--- a/wrapper/kref.h
+++ b/wrapper/kref.h
@@ -1,46 +1,39 @@
-#ifndef _LTTNG_WRAPPER_KREF_H
-#define _LTTNG_WRAPPER_KREF_H
-
-/*
+/* SPDX-License-Identifier: GPL-2.0
+ *
  * wrapper/kref.h
  *
  * wrapper around linux/kref.h.
  *
  * Copyright (C) 2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; only version 2 of the License.
- *
- * This program 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 General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
- *
  * This wrapper code is derived from Linux 3.19.2 include/linux/list.h
  * and include/linux/rculist.h, hence the GPLv2 license applied to this
  * file.
  */
 
+#ifndef _LTTNG_WRAPPER_KREF_H
+#define _LTTNG_WRAPPER_KREF_H
+
 #include <linux/kref.h>
 #include <linux/rculist.h>
+#include <linux/version.h>
 
 /*
  * lttng_kref_get: get reference count, checking for overflow.
  *
  * Return 1 if reference is taken, 0 otherwise (overflow).
  */
+#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,11,0))
+static inline int lttng_kref_get(struct kref *kref)
+{
+       kref_get(kref);
+       return 1;
+}
+#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,11,0)) */
 static inline int lttng_kref_get(struct kref *kref)
 {
-       if (atomic_add_unless(&kref->refcount, 1, INT_MAX) != INT_MAX) {
-               return 1;
-       } else {
-               return 0;
-       }
+       return atomic_add_unless(&kref->refcount, 1, INT_MAX);
 }
+#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,11,0)) */
 
 #endif /* _LTTNG_WRAPPER_KREF_H */