Edit File: rcutree.h
/* * Read-Copy Update mechanism for mutual exclusion (tree-based version) * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * * Copyright IBM Corporation, 2008 * * Author: Dipankar Sarma <dipankar@in.ibm.com> * Paul E. McKenney <paulmck@linux.vnet.ibm.com> Hierarchical algorithm * * Based on the original work by Paul McKenney <paulmck@us.ibm.com> * and inputs from Rusty Russell, Andrea Arcangeli and Andi Kleen. * * For detailed explanation of Read-Copy Update mechanism see - * Documentation/RCU */ #ifndef __LINUX_RCUTREE_H #define __LINUX_RCUTREE_H extern void rcu_init(void); extern void rcu_note_context_switch(int cpu); extern int rcu_needs_cpu(int cpu, u64 *nextevt); extern void rcu_cpu_stall_reset(void); /* * Note a virtualization-based context switch. This is simply a * wrapper around rcu_note_context_switch(), which allows TINY_RCU * to save a few bytes. */ static inline void rcu_virt_note_context_switch(int cpu) { rcu_note_context_switch(cpu); } extern void synchronize_rcu_bh(void); extern void synchronize_sched_expedited(void); extern void synchronize_rcu_expedited(void); void kfree_call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu)); /** * synchronize_rcu_bh_expedited - Brute-force RCU-bh grace period * * Wait for an RCU-bh grace period to elapse, but use a "big hammer" * approach to force the grace period to end quickly. This consumes * significant time on all CPUs and is unfriendly to real-time workloads, * so is thus not recommended for any sort of common-case code. In fact, * if you are using synchronize_rcu_bh_expedited() in a loop, please * restructure your code to batch your updates, and then use a single * synchronize_rcu_bh() instead. * * Note that it is illegal to call this function while holding any lock * that is acquired by a CPU-hotplug notifier. And yes, it is also illegal * to call this function from a CPU-hotplug notifier. Failing to observe * these restriction will result in deadlock. */ static inline void synchronize_rcu_bh_expedited(void) { synchronize_sched_expedited(); } extern void rcu_barrier(void); extern void rcu_barrier_bh(void); extern void rcu_barrier_sched(void); unsigned long get_state_synchronize_rcu(void); void cond_synchronize_rcu(unsigned long oldstate); extern unsigned long rcutorture_testseq; extern unsigned long rcutorture_vernum; extern long rcu_batches_completed(void); extern long rcu_batches_completed_bh(void); extern long rcu_batches_completed_sched(void); extern void rcu_force_quiescent_state(void); extern void rcu_bh_force_quiescent_state(void); extern void rcu_sched_force_quiescent_state(void); extern void rcu_scheduler_starting(void); extern int rcu_scheduler_active __read_mostly; extern bool rcu_is_watching(void); #endif /* __LINUX_RCUTREE_H */