diff options
author | Samuel Thibault <samuel.thibault@ens-lyon.org> | 2013-07-27 22:07:53 +0000 |
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committer | Samuel Thibault <samuel.thibault@ens-lyon.org> | 2013-07-27 22:07:53 +0000 |
commit | 4fbe7358c7747a9165f776eb19addbb9baf7def2 (patch) | |
tree | bc7076b4f6d10c2cc2942539bb666e50f0b66954 /libdde_linux26/contrib/include/linux/rcupdate.h | |
parent | 21adb5284111190057db245cfc2b54091920c373 (diff) |
rename libdde_linux26 into libdde-linux26 to make dpkg-source happy
Diffstat (limited to 'libdde_linux26/contrib/include/linux/rcupdate.h')
-rw-r--r-- | libdde_linux26/contrib/include/linux/rcupdate.h | 274 |
1 files changed, 0 insertions, 274 deletions
diff --git a/libdde_linux26/contrib/include/linux/rcupdate.h b/libdde_linux26/contrib/include/linux/rcupdate.h deleted file mode 100644 index 528343e6..00000000 --- a/libdde_linux26/contrib/include/linux/rcupdate.h +++ /dev/null @@ -1,274 +0,0 @@ -/* - * 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 - * 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, 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: - * http://www.rdrop.com/users/paulmck/paper/rclockpdcsproof.pdf - * 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 - * - */ - -#ifndef __LINUX_RCUPDATE_H -#define __LINUX_RCUPDATE_H - -#include <linux/cache.h> -#include <linux/spinlock.h> -#include <linux/threads.h> -#include <linux/percpu.h> -#include <linux/cpumask.h> -#include <linux/seqlock.h> -#include <linux/lockdep.h> -#include <linux/completion.h> - -/** - * struct rcu_head - callback structure for use with RCU - * @next: next update requests in a list - * @func: actual update function to call after the grace period. - */ -struct rcu_head { - struct rcu_head *next; - void (*func)(struct rcu_head *head); -}; - -/* Internal to kernel, but needed by rcupreempt.h. */ -extern int rcu_scheduler_active; - -#if defined(CONFIG_CLASSIC_RCU) -#include <linux/rcuclassic.h> -#elif defined(CONFIG_TREE_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) */ - -#define RCU_HEAD_INIT { .next = NULL, .func = NULL } -#define RCU_HEAD(head) struct rcu_head head = RCU_HEAD_INIT -#define INIT_RCU_HEAD(ptr) do { \ - (ptr)->next = NULL; (ptr)->func = NULL; \ -} while (0) - -/** - * rcu_read_lock - mark the beginning of an RCU read-side critical section. - * - * When synchronize_rcu() is invoked on one CPU while other CPUs - * are within RCU read-side critical sections, then the - * synchronize_rcu() is guaranteed to block until after all the other - * CPUs exit their critical sections. Similarly, if call_rcu() is invoked - * on one CPU while other CPUs are within RCU read-side critical - * sections, invocation of the corresponding RCU callback is deferred - * until after the all the other CPUs exit their critical sections. - * - * Note, however, that RCU callbacks are permitted to run concurrently - * with RCU read-side critical sections. One way that this can happen - * is via the following sequence of events: (1) CPU 0 enters an RCU - * read-side critical section, (2) CPU 1 invokes call_rcu() to register - * an RCU callback, (3) CPU 0 exits the RCU read-side critical section, - * (4) CPU 2 enters a RCU read-side critical section, (5) the RCU - * callback is invoked. This is legal, because the RCU read-side critical - * section that was running concurrently with the call_rcu() (and which - * therefore might be referencing something that the corresponding RCU - * callback would free up) has completed before the corresponding - * RCU callback is invoked. - * - * RCU read-side critical sections may be nested. Any deferred actions - * will be deferred until the outermost RCU read-side critical section - * completes. - * - * It is illegal to block while in an RCU read-side critical section. - */ -#define rcu_read_lock() __rcu_read_lock() - -/** - * rcu_read_unlock - marks the end of an RCU read-side critical section. - * - * See rcu_read_lock() for more information. - */ - -/* - * So where is rcu_write_lock()? It does not exist, as there is no - * way for writers to lock out RCU readers. This is a feature, not - * a bug -- this property is what provides RCU's performance benefits. - * Of course, writers must coordinate with each other. The normal - * spinlock primitives work well for this, but any other technique may be - * 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() - -/** - * rcu_read_lock_bh - mark the beginning of a softirq-only RCU critical section - * - * This is equivalent of rcu_read_lock(), but to be used when updates - * are being done using call_rcu_bh(). Since call_rcu_bh() callbacks - * consider completion of a softirq handler to be a quiescent state, - * a process in RCU read-side critical section must be protected by - * disabling softirqs. Read-side critical sections in interrupt context - * can use just rcu_read_lock(). - * - */ -#define rcu_read_lock_bh() __rcu_read_lock_bh() - -/* - * 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() - -/** - * rcu_read_lock_sched - mark the beginning of a RCU-classic critical section - * - * Should be used with either - * - synchronize_sched() - * or - * - 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() - -/* - * 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() - - - -/** - * rcu_dereference - fetch an RCU-protected pointer in an - * RCU read-side critical section. This pointer may later - * be safely dereferenced. - * - * Inserts memory barriers on architectures that require them - * (currently only the Alpha), and, more importantly, documents - * exactly which pointers are protected by RCU. - */ - -#define rcu_dereference(p) ({ \ - typeof(p) _________p1 = ACCESS_ONCE(p); \ - smp_read_barrier_depends(); \ - (_________p1); \ - }) - -/** - * rcu_assign_pointer - assign (publicize) a pointer to a newly - * initialized structure that will be dereferenced by RCU read-side - * critical sections. Returns the value assigned. - * - * Inserts memory barriers on architectures that require them - * (pretty much all of them other than x86), and also prevents - * the compiler from reordering the code that initializes the - * structure after the pointer assignment. More importantly, this - * call documents which pointers will be dereferenced by RCU read-side - * code. - */ - -#define rcu_assign_pointer(p, v) \ - ({ \ - if (!__builtin_constant_p(v) || \ - ((v) != NULL)) \ - smp_wmb(); \ - (p) = (v); \ - }) - -/* Infrastructure to implement the synchronize_() primitives. */ - -struct rcu_synchronize { - struct rcu_head head; - struct completion completion; -}; - -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 - * - * The update function will be invoked some time after a full grace - * period elapses, in other words after all currently executing RCU - * read-side critical sections have completed. RCU read-side critical - * sections are delimited by rcu_read_lock() and rcu_read_unlock(), - * and may be nested. - */ -extern void call_rcu(struct rcu_head *head, - void (*func)(struct rcu_head *head)); - -/** - * call_rcu_bh - Queue an RCU for invocation after a quicker grace period. - * @head: structure to be used for queueing the RCU updates. - * @func: actual update function to be invoked after the grace period - * - * The update function will be invoked some time after a full grace - * period elapses, in other words after all currently executing RCU - * read-side critical sections have completed. call_rcu_bh() assumes - * that the read-side critical sections end on completion of a softirq - * handler. This means that read-side critical sections in process - * context must not be interrupted by softirqs. This interface is to be - * used when most of the read-side critical sections are in softirq context. - * RCU read-side critical sections are delimited by : - * - rcu_read_lock() and rcu_read_unlock(), if in interrupt context. - * OR - * - rcu_read_lock_bh() and rcu_read_unlock_bh(), if in process context. - * These may be nested. - */ -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 */ |