diff options
Diffstat (limited to 'include/linux/rcupdate.h')
| -rw-r--r-- | include/linux/rcupdate.h | 127 |
1 files changed, 79 insertions, 48 deletions
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 15fbb3ca634d..6fe0363724e9 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -1,5 +1,5 @@ /* - * Read-Copy Update mechanism for mutual exclusion + * Read-Copy Update mechanism for mutual exclusion * * 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 @@ -18,7 +18,7 @@ * Copyright IBM Corporation, 2001 * * Author: Dipankar Sarma <dipankar@in.ibm.com> - * + * * Based on the original work by Paul McKenney <paulmck@us.ibm.com> * and inputs from Rusty Russell, Andrea Arcangeli and Andi Kleen. * Papers: @@ -26,7 +26,7 @@ * http://lse.sourceforge.net/locking/rclock_OLS.2001.05.01c.sc.pdf (OLS2001) * * For detailed explanation of Read-Copy Update mechanism see - - * http://lse.sourceforge.net/locking/rcupdate.html + * http://lse.sourceforge.net/locking/rcupdate.html * */ @@ -51,18 +51,31 @@ struct rcu_head { void (*func)(struct rcu_head *head); }; -/* Internal to kernel, but needed by rcupreempt.h. */ +/* Exported common interfaces */ +#ifdef CONFIG_TREE_PREEMPT_RCU +extern void synchronize_rcu(void); +#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */ +#define synchronize_rcu synchronize_sched +#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */ +extern void synchronize_rcu_bh(void); +extern void synchronize_sched(void); +extern void rcu_barrier(void); +extern void rcu_barrier_bh(void); +extern void rcu_barrier_sched(void); +extern void synchronize_sched_expedited(void); +extern int sched_expedited_torture_stats(char *page); + +/* Internal to kernel */ +extern void rcu_init(void); +extern void rcu_scheduler_starting(void); +extern int rcu_needs_cpu(int cpu); extern int rcu_scheduler_active; -#if defined(CONFIG_CLASSIC_RCU) -#include <linux/rcuclassic.h> -#elif defined(CONFIG_TREE_RCU) +#if defined(CONFIG_TREE_RCU) || defined(CONFIG_TREE_PREEMPT_RCU) #include <linux/rcutree.h> -#elif defined(CONFIG_PREEMPT_RCU) -#include <linux/rcupreempt.h> #else #error "Unknown RCU implementation specified to kernel configuration" -#endif /* #else #if defined(CONFIG_CLASSIC_RCU) */ +#endif #define RCU_HEAD_INIT { .next = NULL, .func = NULL } #define RCU_HEAD(head) struct rcu_head head = RCU_HEAD_INIT @@ -70,6 +83,16 @@ extern int rcu_scheduler_active; (ptr)->next = NULL; (ptr)->func = NULL; \ } while (0) +#ifdef CONFIG_DEBUG_LOCK_ALLOC +extern struct lockdep_map rcu_lock_map; +# define rcu_read_acquire() \ + lock_acquire(&rcu_lock_map, 0, 0, 2, 1, NULL, _THIS_IP_) +# define rcu_read_release() lock_release(&rcu_lock_map, 1, _THIS_IP_) +#else +# define rcu_read_acquire() do { } while (0) +# define rcu_read_release() do { } while (0) +#endif + /** * rcu_read_lock - mark the beginning of an RCU read-side critical section. * @@ -99,7 +122,12 @@ extern int rcu_scheduler_active; * * It is illegal to block while in an RCU read-side critical section. */ -#define rcu_read_lock() __rcu_read_lock() +static inline void rcu_read_lock(void) +{ + __rcu_read_lock(); + __acquire(RCU); + rcu_read_acquire(); +} /** * rcu_read_unlock - marks the end of an RCU read-side critical section. @@ -116,7 +144,12 @@ extern int rcu_scheduler_active; * used as well. RCU does not care how the writers keep out of each * others' way, as long as they do so. */ -#define rcu_read_unlock() __rcu_read_unlock() +static inline void rcu_read_unlock(void) +{ + rcu_read_release(); + __release(RCU); + __rcu_read_unlock(); +} /** * rcu_read_lock_bh - mark the beginning of a softirq-only RCU critical section @@ -129,14 +162,24 @@ extern int rcu_scheduler_active; * can use just rcu_read_lock(). * */ -#define rcu_read_lock_bh() __rcu_read_lock_bh() +static inline void rcu_read_lock_bh(void) +{ + __rcu_read_lock_bh(); + __acquire(RCU_BH); + rcu_read_acquire(); +} /* * rcu_read_unlock_bh - marks the end of a softirq-only RCU critical section * * See rcu_read_lock_bh() for more information. */ -#define rcu_read_unlock_bh() __rcu_read_unlock_bh() +static inline void rcu_read_unlock_bh(void) +{ + rcu_read_release(); + __release(RCU_BH); + __rcu_read_unlock_bh(); +} /** * rcu_read_lock_sched - mark the beginning of a RCU-classic critical section @@ -147,17 +190,34 @@ extern int rcu_scheduler_active; * - call_rcu_sched() and rcu_barrier_sched() * on the write-side to insure proper synchronization. */ -#define rcu_read_lock_sched() preempt_disable() -#define rcu_read_lock_sched_notrace() preempt_disable_notrace() +static inline void rcu_read_lock_sched(void) +{ + preempt_disable(); + __acquire(RCU_SCHED); + rcu_read_acquire(); +} +static inline notrace void rcu_read_lock_sched_notrace(void) +{ + preempt_disable_notrace(); + __acquire(RCU_SCHED); +} /* * rcu_read_unlock_sched - marks the end of a RCU-classic critical section * * See rcu_read_lock_sched for more information. */ -#define rcu_read_unlock_sched() preempt_enable() -#define rcu_read_unlock_sched_notrace() preempt_enable_notrace() - +static inline void rcu_read_unlock_sched(void) +{ + rcu_read_release(); + __release(RCU_SCHED); + preempt_enable(); +} +static inline notrace void rcu_read_unlock_sched_notrace(void) +{ + __release(RCU_SCHED); + preempt_enable_notrace(); +} /** @@ -207,24 +267,6 @@ struct rcu_synchronize { extern void wakeme_after_rcu(struct rcu_head *head); /** - * synchronize_sched - block until all CPUs have exited any non-preemptive - * kernel code sequences. - * - * This means that all preempt_disable code sequences, including NMI and - * hardware-interrupt handlers, in progress on entry will have completed - * before this primitive returns. However, this does not guarantee that - * softirq handlers will have completed, since in some kernels, these - * handlers can run in process context, and can block. - * - * This primitive provides the guarantees made by the (now removed) - * synchronize_kernel() API. In contrast, synchronize_rcu() only - * guarantees that rcu_read_lock() sections will have completed. - * In "classic RCU", these two guarantees happen to be one and - * the same, but can differ in realtime RCU implementations. - */ -#define synchronize_sched() __synchronize_sched() - -/** * call_rcu - Queue an RCU callback for invocation after a grace period. * @head: structure to be used for queueing the RCU updates. * @func: actual update function to be invoked after the grace period @@ -259,15 +301,4 @@ extern void call_rcu(struct rcu_head *head, extern void call_rcu_bh(struct rcu_head *head, void (*func)(struct rcu_head *head)); -/* Exported common interfaces */ -extern void synchronize_rcu(void); -extern void rcu_barrier(void); -extern void rcu_barrier_bh(void); -extern void rcu_barrier_sched(void); - -/* Internal to kernel */ -extern void rcu_init(void); -extern void rcu_scheduler_starting(void); -extern int rcu_needs_cpu(int cpu); - #endif /* __LINUX_RCUPDATE_H */ |