1 /* SPDX-License-Identifier: GPL-2.0+ */ 2 /* 3 * Read-Copy Update mechanism for mutual exclusion (tree-based version) 4 * 5 * Copyright IBM Corporation, 2008 6 * 7 * Author: Dipankar Sarma <dipankar@in.ibm.com> 8 * Paul E. McKenney <paulmck@linux.ibm.com> Hierarchical algorithm 9 * 10 * Based on the original work by Paul McKenney <paulmck@linux.ibm.com> 11 * and inputs from Rusty Russell, Andrea Arcangeli and Andi Kleen. 12 * 13 * For detailed explanation of Read-Copy Update mechanism see - 14 * Documentation/RCU 15 */ 16 17 #ifndef __LINUX_RCUTREE_H 18 #define __LINUX_RCUTREE_H 19 20 void rcu_softirq_qs(void); 21 void rcu_note_context_switch(bool preempt); 22 int rcu_needs_cpu(u64 basem, u64 *nextevt); 23 void rcu_cpu_stall_reset(void); 24 25 /* 26 * Note a virtualization-based context switch. This is simply a 27 * wrapper around rcu_note_context_switch(), which allows TINY_RCU 28 * to save a few bytes. The caller must have disabled interrupts. 29 */ rcu_virt_note_context_switch(int cpu)30static inline void rcu_virt_note_context_switch(int cpu) 31 { 32 rcu_note_context_switch(false); 33 } 34 35 void synchronize_rcu_expedited(void); 36 void kvfree_call_rcu(struct rcu_head *head, rcu_callback_t func); 37 38 void rcu_barrier(void); 39 bool rcu_eqs_special_set(int cpu); 40 void rcu_momentary_dyntick_idle(void); 41 void kfree_rcu_scheduler_running(void); 42 bool rcu_gp_might_be_stalled(void); 43 unsigned long get_state_synchronize_rcu(void); 44 unsigned long start_poll_synchronize_rcu(void); 45 bool poll_state_synchronize_rcu(unsigned long oldstate); 46 void cond_synchronize_rcu(unsigned long oldstate); 47 48 void rcu_idle_enter(void); 49 void rcu_idle_exit(void); 50 void rcu_irq_enter(void); 51 void rcu_irq_exit(void); 52 void rcu_irq_enter_irqson(void); 53 void rcu_irq_exit_irqson(void); 54 bool rcu_is_idle_cpu(int cpu); 55 56 #ifdef CONFIG_PROVE_RCU 57 void rcu_irq_exit_check_preempt(void); 58 #else rcu_irq_exit_check_preempt(void)59static inline void rcu_irq_exit_check_preempt(void) { } 60 #endif 61 62 void exit_rcu(void); 63 64 void rcu_scheduler_starting(void); 65 extern int rcu_scheduler_active __read_mostly; 66 void rcu_end_inkernel_boot(void); 67 bool rcu_inkernel_boot_has_ended(void); 68 bool rcu_is_watching(void); 69 #ifndef CONFIG_PREEMPTION 70 void rcu_all_qs(void); 71 #endif 72 73 /* RCUtree hotplug events */ 74 int rcutree_prepare_cpu(unsigned int cpu); 75 int rcutree_online_cpu(unsigned int cpu); 76 int rcutree_offline_cpu(unsigned int cpu); 77 int rcutree_dead_cpu(unsigned int cpu); 78 int rcutree_dying_cpu(unsigned int cpu); 79 void rcu_cpu_starting(unsigned int cpu); 80 81 #endif /* __LINUX_RCUTREE_H */ 82