include/linux/rcutree.h

0001 /* SPDX-License-Identifier: GPL-2.0+ */
0002 /*
0003  * Read-Copy Update mechanism for mutual exclusion (tree-based version)
0004  *
0005  * Copyright IBM Corporation, 2008
0006  *
0007  * Author: Dipankar Sarma <dipankar@in.ibm.com>
0008  *     Paul E. McKenney <paulmck@linux.ibm.com> Hierarchical algorithm
0009  *
0010  * Based on the original work by Paul McKenney <paulmck@linux.ibm.com>
0011  * and inputs from Rusty Russell, Andrea Arcangeli and Andi Kleen.
0012  *
0013  * For detailed explanation of Read-Copy Update mechanism see -
0014  *  Documentation/RCU
0015  */
0016
0017 #ifndef __LINUX_RCUTREE_H
0018 #define __LINUX_RCUTREE_H
0019
0020 void rcu_softirq_qs(void);
0021 void rcu_note_context_switch(bool preempt);
0022 int rcu_needs_cpu(void);
0023 void rcu_cpu_stall_reset(void);
0024
0025 /*
0026  * Note a virtualization-based context switch.  This is simply a
0027  * wrapper around rcu_note_context_switch(), which allows TINY_RCU
0028  * to save a few bytes. The caller must have disabled interrupts.
0029  */
0030 static inline void rcu_virt_note_context_switch(int cpu)
0031 {
0032     rcu_note_context_switch(false);
0033 }
0034
0035 void synchronize_rcu_expedited(void);
0036 void kvfree_call_rcu(struct rcu_head *head, rcu_callback_t func);
0037
0038 void rcu_barrier(void);
0039 bool rcu_eqs_special_set(int cpu);
0040 void rcu_momentary_dyntick_idle(void);
0041 void kfree_rcu_scheduler_running(void);
0042 bool rcu_gp_might_be_stalled(void);
0043 unsigned long start_poll_synchronize_rcu_expedited(void);
0044 void cond_synchronize_rcu_expedited(unsigned long oldstate);
0045 unsigned long get_state_synchronize_rcu(void);
0046 unsigned long start_poll_synchronize_rcu(void);
0047 bool poll_state_synchronize_rcu(unsigned long oldstate);
0048 void cond_synchronize_rcu(unsigned long oldstate);
0049
0050 bool rcu_is_idle_cpu(int cpu);
0051
0052 #ifdef CONFIG_PROVE_RCU
0053 void rcu_irq_exit_check_preempt(void);
0054 #else
0055 static inline void rcu_irq_exit_check_preempt(void) { }
0056 #endif
0057
0058 struct task_struct;
0059 void rcu_preempt_deferred_qs(struct task_struct *t);
0060
0061 void exit_rcu(void);
0062
0063 void rcu_scheduler_starting(void);
0064 extern int rcu_scheduler_active;
0065 void rcu_end_inkernel_boot(void);
0066 bool rcu_inkernel_boot_has_ended(void);
0067 bool rcu_is_watching(void);
0068 #ifndef CONFIG_PREEMPTION
0069 void rcu_all_qs(void);
0070 #endif
0071
0072 /* RCUtree hotplug events */
0073 int rcutree_prepare_cpu(unsigned int cpu);
0074 int rcutree_online_cpu(unsigned int cpu);
0075 int rcutree_offline_cpu(unsigned int cpu);
0076 int rcutree_dead_cpu(unsigned int cpu);
0077 int rcutree_dying_cpu(unsigned int cpu);
0078 void rcu_cpu_starting(unsigned int cpu);
0079
0080 #endif /* __LINUX_RCUTREE_H */