/* * Read-Copy Update mechanism for mutual exclusion, the Bloatwatch edition. * * 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, you can access it online at * http://www.gnu.org/licenses/gpl-2.0.html. * * Copyright IBM Corporation, 2008 * * Author: Paul E. McKenney * * For detailed explanation of Read-Copy Update mechanism see - * Documentation/RCU */ #ifndef __LINUX_TINY_H #define __LINUX_TINY_H #include struct rcu_dynticks; static inline int rcu_dynticks_snap(struct rcu_dynticks *rdtp) { return 0; } static inline bool rcu_eqs_special_set(int cpu) { return false; /* Never flag non-existent other CPUs! */ } static inline unsigned long get_state_synchronize_rcu(void) { return 0; } static inline void cond_synchronize_rcu(unsigned long oldstate) { might_sleep(); } static inline unsigned long get_state_synchronize_sched(void) { return 0; } static inline void cond_synchronize_sched(unsigned long oldstate) { might_sleep(); } extern void rcu_barrier_bh(void); extern void rcu_barrier_sched(void); static inline void synchronize_rcu_expedited(void) { synchronize_sched(); /* Only one CPU, so pretty fast anyway!!! */ } static inline void rcu_barrier(void) { rcu_barrier_sched(); /* Only one CPU, so only one list of callbacks! */ } static inline void synchronize_rcu_bh(void) { synchronize_sched(); } static inline void synchronize_rcu_bh_expedited(void) { synchronize_sched(); } static inline void synchronize_sched_expedited(void) { synchronize_sched(); } static inline void kfree_call_rcu(struct rcu_head *head, rcu_callback_t func) { call_rcu(head, func); } #define rcu_note_context_switch(preempt) \ do { \ rcu_sched_qs(); \ rcu_note_voluntary_context_switch_lite(current); \ } while (0) /* * Take advantage of the fact that there is only one CPU, which * allows us to ignore virtualization-based context switches. */ static inline void rcu_virt_note_context_switch(int cpu) { } /* * Return the number of grace periods started. */ static inline unsigned long rcu_batches_started(void) { return 0; } /* * Return the number of bottom-half grace periods started. */ static inline unsigned long rcu_batches_started_bh(void) { return 0; } /* * Return the number of sched grace periods started. */ static inline unsigned long rcu_batches_started_sched(void) { return 0; } /* * Return the number of grace periods completed. */ static inline unsigned long rcu_batches_completed(void) { return 0; } /* * Return the number of bottom-half grace periods completed. */ static inline unsigned long rcu_batches_completed_bh(void) { return 0; } /* * Return the number of sched grace periods completed. */ static inline unsigned long rcu_batches_completed_sched(void) { return 0; } /* * Return the number of expedited grace periods completed. */ static inline unsigned long rcu_exp_batches_completed(void) { return 0; } /* * Return the number of expedited sched grace periods completed. */ static inline unsigned long rcu_exp_batches_completed_sched(void) { return 0; } static inline void rcu_force_quiescent_state(void) { } static inline void rcu_bh_force_quiescent_state(void) { } static inline void rcu_sched_force_quiescent_state(void) { } static inline void show_rcu_gp_kthreads(void) { } static inline void rcu_cpu_stall_reset(void) { } static inline void rcu_idle_enter(void) { } static inline void rcu_idle_exit(void) { } static inline void rcu_irq_enter(void) { } static inline bool rcu_irq_enter_disabled(void) { return false; } static inline void rcu_irq_exit_irqson(void) { } static inline void rcu_irq_enter_irqson(void) { } static inline void rcu_irq_exit(void) { } static inline void exit_rcu(void) { } #if defined(CONFIG_DEBUG_LOCK_ALLOC) || defined(CONFIG_SRCU) extern int rcu_scheduler_active __read_mostly; void rcu_scheduler_starting(void); #else /* #if defined(CONFIG_DEBUG_LOCK_ALLOC) || defined(CONFIG_SRCU) */ static inline void rcu_scheduler_starting(void) { } #endif /* #else #if defined(CONFIG_DEBUG_LOCK_ALLOC) || defined(CONFIG_SRCU) */ static inline bool rcu_is_watching(void) { return true; } static inline void rcu_request_urgent_qs_task(struct task_struct *t) { } static inline void rcu_all_qs(void) { barrier(); /* Avoid RCU read-side critical sections leaking across. */ } /* RCUtree hotplug events */ #define rcutree_prepare_cpu NULL #define rcutree_online_cpu NULL #define rcutree_offline_cpu NULL #define rcutree_dead_cpu NULL #define rcutree_dying_cpu NULL #endif /* __LINUX_RCUTINY_H */