1 /* 2 * Read-Copy Update mechanism for mutual exclusion (tree-based version) 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License as published by 6 * the Free Software Foundation; either version 2 of the License, or 7 * (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, you can access it online at 16 * http://www.gnu.org/licenses/gpl-2.0.html. 17 * 18 * Copyright IBM Corporation, 2008 19 * 20 * Author: Dipankar Sarma <[email protected]> 21 * Paul E. McKenney <[email protected]> Hierarchical algorithm 22 * 23 * Based on the original work by Paul McKenney <[email protected]> 24 * and inputs from Rusty Russell, Andrea Arcangeli and Andi Kleen. 25 * 26 * For detailed explanation of Read-Copy Update mechanism see - 27 * Documentation/RCU 28 */ 29 30 #ifndef __LINUX_RCUTREE_H 31 #define __LINUX_RCUTREE_H 32 33 void rcu_softirq_qs(void); 34 void rcu_note_context_switch(bool preempt); 35 int rcu_needs_cpu(u64 basem, u64 *nextevt); 36 void rcu_cpu_stall_reset(void); 37 38 /* 39 * Note a virtualization-based context switch. This is simply a 40 * wrapper around rcu_note_context_switch(), which allows TINY_RCU 41 * to save a few bytes. The caller must have disabled interrupts. 42 */ 43 static inline void rcu_virt_note_context_switch(int cpu) 44 { 45 rcu_note_context_switch(false); 46 } 47 48 void synchronize_rcu_expedited(void); 49 void kfree_call_rcu(struct rcu_head *head, rcu_callback_t func); 50 51 void rcu_barrier(void); 52 bool rcu_eqs_special_set(int cpu); 53 unsigned long get_state_synchronize_rcu(void); 54 void cond_synchronize_rcu(unsigned long oldstate); 55 56 void rcu_idle_enter(void); 57 void rcu_idle_exit(void); 58 void rcu_irq_enter(void); 59 void rcu_irq_exit(void); 60 void rcu_irq_enter_irqson(void); 61 void rcu_irq_exit_irqson(void); 62 63 void exit_rcu(void); 64 65 void rcu_scheduler_starting(void); 66 extern int rcu_scheduler_active __read_mostly; 67 void rcu_end_inkernel_boot(void); 68 bool rcu_is_watching(void); 69 #ifndef CONFIG_PREEMPT 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