1/* SPDX-License-Identifier: GPL-2.0+ */
2/*
3 * Read-Copy Update notifiers, initially RCU CPU stall notifier.
4 * Separate from rcupdate.h to avoid #include loops.
5 *
6 * Copyright (C) 2023 Paul E. McKenney.
7 */
8
9#ifndef __LINUX_RCU_NOTIFIER_H
10#define __LINUX_RCU_NOTIFIER_H
11
12// Actions for RCU CPU stall notifier calls.
13#define RCU_STALL_NOTIFY_NORM 1
14#define RCU_STALL_NOTIFY_EXP 2
15
16#if defined(CONFIG_RCU_STALL_COMMON) && defined(CONFIG_RCU_CPU_STALL_NOTIFIER)
17
18#include <linux/notifier.h>
19#include <linux/types.h>
20
21int rcu_stall_chain_notifier_register(struct notifier_block *n);
22int rcu_stall_chain_notifier_unregister(struct notifier_block *n);
23
24#else // #if defined(CONFIG_RCU_STALL_COMMON) && defined(CONFIG_RCU_CPU_STALL_NOTIFIER)
25
26// No RCU CPU stall warnings in Tiny RCU.
27static inline int rcu_stall_chain_notifier_register(struct notifier_block *n) { return -EEXIST; }
28static inline int rcu_stall_chain_notifier_unregister(struct notifier_block *n) { return -ENOENT; }
29
30#endif // #else // #if defined(CONFIG_RCU_STALL_COMMON) && defined(CONFIG_RCU_CPU_STALL_NOTIFIER)
31
32#endif /* __LINUX_RCU_NOTIFIER_H */
33