1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
|
/* SPDX-License-Identifier: GPL-2.0-only
*
* wrapper/kref.h
*
* wrapper around linux/kref.h.
*
* Copyright (C) 2016 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
*
* 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 <lttng/kernel-version.h>
/*
* lttng_kref_get: get reference count, checking for overflow.
*
* Return 1 if reference is taken, 0 otherwise (overflow).
*/
#if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,11,0))
static inline int lttng_kref_get(struct kref *kref)
{
kref_get(kref);
return 1;
}
#else /* #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,11,0)) */
static inline int lttng_kref_get(struct kref *kref)
{
return atomic_add_unless(&kref->refcount, 1, INT_MAX);
}
#endif /* #else #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,11,0)) */
#endif /* _LTTNG_WRAPPER_KREF_H */
|
