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@@ -1,668 +0,0 @@
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-/*
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- * Sleepable Read-Copy Update mechanism for mutual exclusion.
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- *
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- * This program is free software; you can redistribute it and/or modify
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- * it under the terms of the GNU General Public License as published by
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- * the Free Software Foundation; either version 2 of the License, or
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- * (at your option) any later version.
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- *
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- * This program is distributed in the hope that it will be useful,
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- * but WITHOUT ANY WARRANTY; without even the implied warranty of
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- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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- * GNU General Public License for more details.
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- *
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- * You should have received a copy of the GNU General Public License
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- * along with this program; if not, you can access it online at
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- * http://www.gnu.org/licenses/gpl-2.0.html.
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- *
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- * Copyright (C) IBM Corporation, 2006
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- * Copyright (C) Fujitsu, 2012
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- *
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- * Author: Paul McKenney <paulmck@us.ibm.com>
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- * Lai Jiangshan <laijs@cn.fujitsu.com>
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- *
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- * For detailed explanation of Read-Copy Update mechanism see -
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- * Documentation/RCU/ *.txt
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- *
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- */
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-
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-#include <linux/export.h>
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-#include <linux/mutex.h>
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-#include <linux/percpu.h>
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-#include <linux/preempt.h>
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-#include <linux/rcupdate_wait.h>
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-#include <linux/sched.h>
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-#include <linux/smp.h>
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-#include <linux/delay.h>
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-#include <linux/srcu.h>
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-
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-#include "rcu.h"
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-
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-/*
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- * Initialize an rcu_batch structure to empty.
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- */
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-static inline void rcu_batch_init(struct rcu_batch *b)
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-{
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- b->head = NULL;
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- b->tail = &b->head;
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-}
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-
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-/*
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- * Enqueue a callback onto the tail of the specified rcu_batch structure.
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- */
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-static inline void rcu_batch_queue(struct rcu_batch *b, struct rcu_head *head)
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-{
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- *b->tail = head;
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- b->tail = &head->next;
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-}
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-
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-/*
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- * Is the specified rcu_batch structure empty?
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- */
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-static inline bool rcu_batch_empty(struct rcu_batch *b)
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-{
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- return b->tail == &b->head;
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-}
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-
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-/*
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- * Remove the callback at the head of the specified rcu_batch structure
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- * and return a pointer to it, or return NULL if the structure is empty.
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- */
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-static inline struct rcu_head *rcu_batch_dequeue(struct rcu_batch *b)
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-{
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- struct rcu_head *head;
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-
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- if (rcu_batch_empty(b))
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- return NULL;
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-
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- head = b->head;
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- b->head = head->next;
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- if (b->tail == &head->next)
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- rcu_batch_init(b);
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-
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- return head;
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-}
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-
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-/*
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- * Move all callbacks from the rcu_batch structure specified by "from" to
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- * the structure specified by "to".
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- */
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-static inline void rcu_batch_move(struct rcu_batch *to, struct rcu_batch *from)
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-{
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- if (!rcu_batch_empty(from)) {
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- *to->tail = from->head;
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- to->tail = from->tail;
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- rcu_batch_init(from);
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- }
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-}
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-
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-static int init_srcu_struct_fields(struct srcu_struct *sp)
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-{
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- sp->completed = 0;
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- spin_lock_init(&sp->queue_lock);
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- sp->running = false;
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- rcu_batch_init(&sp->batch_queue);
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- rcu_batch_init(&sp->batch_check0);
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- rcu_batch_init(&sp->batch_check1);
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- rcu_batch_init(&sp->batch_done);
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- INIT_DELAYED_WORK(&sp->work, process_srcu);
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- sp->per_cpu_ref = alloc_percpu(struct srcu_array);
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- return sp->per_cpu_ref ? 0 : -ENOMEM;
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-}
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-
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-#ifdef CONFIG_DEBUG_LOCK_ALLOC
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-
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-int __init_srcu_struct(struct srcu_struct *sp, const char *name,
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- struct lock_class_key *key)
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-{
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- /* Don't re-initialize a lock while it is held. */
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- debug_check_no_locks_freed((void *)sp, sizeof(*sp));
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- lockdep_init_map(&sp->dep_map, name, key, 0);
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- return init_srcu_struct_fields(sp);
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-}
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-EXPORT_SYMBOL_GPL(__init_srcu_struct);
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-
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-#else /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
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-
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-/**
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- * init_srcu_struct - initialize a sleep-RCU structure
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- * @sp: structure to initialize.
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- *
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- * Must invoke this on a given srcu_struct before passing that srcu_struct
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- * to any other function. Each srcu_struct represents a separate domain
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- * of SRCU protection.
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- */
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-int init_srcu_struct(struct srcu_struct *sp)
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-{
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- return init_srcu_struct_fields(sp);
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-}
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-EXPORT_SYMBOL_GPL(init_srcu_struct);
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-
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-#endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */
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-
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-/*
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- * Returns approximate total of the readers' ->lock_count[] values for the
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- * rank of per-CPU counters specified by idx.
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- */
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-static unsigned long srcu_readers_lock_idx(struct srcu_struct *sp, int idx)
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-{
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- int cpu;
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- unsigned long sum = 0;
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-
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- for_each_possible_cpu(cpu) {
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- struct srcu_array *cpuc = per_cpu_ptr(sp->per_cpu_ref, cpu);
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-
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- sum += READ_ONCE(cpuc->lock_count[idx]);
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- }
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- return sum;
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-}
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-
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-/*
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- * Returns approximate total of the readers' ->unlock_count[] values for the
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- * rank of per-CPU counters specified by idx.
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- */
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-static unsigned long srcu_readers_unlock_idx(struct srcu_struct *sp, int idx)
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-{
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- int cpu;
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- unsigned long sum = 0;
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-
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- for_each_possible_cpu(cpu) {
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- struct srcu_array *cpuc = per_cpu_ptr(sp->per_cpu_ref, cpu);
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-
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- sum += READ_ONCE(cpuc->unlock_count[idx]);
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- }
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- return sum;
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-}
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-
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-/*
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- * Return true if the number of pre-existing readers is determined to
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- * be zero.
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- */
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-static bool srcu_readers_active_idx_check(struct srcu_struct *sp, int idx)
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-{
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- unsigned long unlocks;
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-
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- unlocks = srcu_readers_unlock_idx(sp, idx);
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-
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- /*
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- * Make sure that a lock is always counted if the corresponding unlock
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- * is counted. Needs to be a smp_mb() as the read side may contain a
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- * read from a variable that is written to before the synchronize_srcu()
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- * in the write side. In this case smp_mb()s A and B act like the store
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- * buffering pattern.
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- *
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- * This smp_mb() also pairs with smp_mb() C to prevent accesses after the
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- * synchronize_srcu() from being executed before the grace period ends.
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- */
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- smp_mb(); /* A */
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-
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- /*
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- * If the locks are the same as the unlocks, then there must have
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- * been no readers on this index at some time in between. This does not
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- * mean that there are no more readers, as one could have read the
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- * current index but not have incremented the lock counter yet.
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- *
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- * Possible bug: There is no guarantee that there haven't been ULONG_MAX
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- * increments of ->lock_count[] since the unlocks were counted, meaning
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- * that this could return true even if there are still active readers.
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- * Since there are no memory barriers around srcu_flip(), the CPU is not
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- * required to increment ->completed before running
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- * srcu_readers_unlock_idx(), which means that there could be an
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- * arbitrarily large number of critical sections that execute after
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- * srcu_readers_unlock_idx() but use the old value of ->completed.
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- */
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- return srcu_readers_lock_idx(sp, idx) == unlocks;
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-}
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-
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-/**
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- * srcu_readers_active - returns true if there are readers. and false
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- * otherwise
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- * @sp: which srcu_struct to count active readers (holding srcu_read_lock).
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- *
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- * Note that this is not an atomic primitive, and can therefore suffer
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- * severe errors when invoked on an active srcu_struct. That said, it
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- * can be useful as an error check at cleanup time.
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- */
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-static bool srcu_readers_active(struct srcu_struct *sp)
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-{
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- int cpu;
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- unsigned long sum = 0;
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-
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- for_each_possible_cpu(cpu) {
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- struct srcu_array *cpuc = per_cpu_ptr(sp->per_cpu_ref, cpu);
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-
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- sum += READ_ONCE(cpuc->lock_count[0]);
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- sum += READ_ONCE(cpuc->lock_count[1]);
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- sum -= READ_ONCE(cpuc->unlock_count[0]);
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- sum -= READ_ONCE(cpuc->unlock_count[1]);
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- }
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- return sum;
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-}
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-
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-/**
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- * cleanup_srcu_struct - deconstruct a sleep-RCU structure
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- * @sp: structure to clean up.
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- *
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- * Must invoke this only after you are finished using a given srcu_struct
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- * that was initialized via init_srcu_struct(). This code does some
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- * probabalistic checking, spotting late uses of srcu_read_lock(),
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- * synchronize_srcu(), synchronize_srcu_expedited(), and call_srcu().
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- * If any such late uses are detected, the per-CPU memory associated with
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- * the srcu_struct is simply leaked and WARN_ON() is invoked. If the
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- * caller frees the srcu_struct itself, a use-after-free crash will likely
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- * ensue, but at least there will be a warning printed.
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- */
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-void cleanup_srcu_struct(struct srcu_struct *sp)
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-{
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- if (WARN_ON(srcu_readers_active(sp)))
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- return; /* Leakage unless caller handles error. */
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- free_percpu(sp->per_cpu_ref);
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- sp->per_cpu_ref = NULL;
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-}
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-EXPORT_SYMBOL_GPL(cleanup_srcu_struct);
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-
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-/*
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- * Counts the new reader in the appropriate per-CPU element of the
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- * srcu_struct.
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- * Returns an index that must be passed to the matching srcu_read_unlock().
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- */
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-int __srcu_read_lock(struct srcu_struct *sp)
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-{
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- int idx;
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-
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- idx = READ_ONCE(sp->completed) & 0x1;
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- this_cpu_inc(sp->per_cpu_ref->lock_count[idx]);
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- smp_mb(); /* B */ /* Avoid leaking the critical section. */
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- return idx;
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-}
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-EXPORT_SYMBOL_GPL(__srcu_read_lock);
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-
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-/*
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- * Removes the count for the old reader from the appropriate per-CPU
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- * element of the srcu_struct. Note that this may well be a different
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- * CPU than that which was incremented by the corresponding srcu_read_lock().
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- */
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-void __srcu_read_unlock(struct srcu_struct *sp, int idx)
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-{
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- smp_mb(); /* C */ /* Avoid leaking the critical section. */
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- this_cpu_inc(sp->per_cpu_ref->unlock_count[idx]);
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-}
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-EXPORT_SYMBOL_GPL(__srcu_read_unlock);
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-
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-/*
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- * We use an adaptive strategy for synchronize_srcu() and especially for
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- * synchronize_srcu_expedited(). We spin for a fixed time period
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- * (defined below) to allow SRCU readers to exit their read-side critical
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- * sections. If there are still some readers after 10 microseconds,
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- * we repeatedly block for 1-millisecond time periods. This approach
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- * has done well in testing, so there is no need for a config parameter.
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- */
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-#define SRCU_RETRY_CHECK_DELAY 5
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-#define SYNCHRONIZE_SRCU_TRYCOUNT 2
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-#define SYNCHRONIZE_SRCU_EXP_TRYCOUNT 12
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-
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-/*
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- * @@@ Wait until all pre-existing readers complete. Such readers
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- * will have used the index specified by "idx".
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- * the caller should ensures the ->completed is not changed while checking
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- * and idx = (->completed & 1) ^ 1
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- */
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-static bool try_check_zero(struct srcu_struct *sp, int idx, int trycount)
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-{
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- for (;;) {
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- if (srcu_readers_active_idx_check(sp, idx))
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- return true;
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- if (--trycount <= 0)
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- return false;
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- udelay(SRCU_RETRY_CHECK_DELAY);
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- }
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-}
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-
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-/*
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- * Increment the ->completed counter so that future SRCU readers will
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- * use the other rank of the ->(un)lock_count[] arrays. This allows
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- * us to wait for pre-existing readers in a starvation-free manner.
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- */
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-static void srcu_flip(struct srcu_struct *sp)
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-{
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- WRITE_ONCE(sp->completed, sp->completed + 1);
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-
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- /*
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- * Ensure that if the updater misses an __srcu_read_unlock()
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- * increment, that task's next __srcu_read_lock() will see the
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- * above counter update. Note that both this memory barrier
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- * and the one in srcu_readers_active_idx_check() provide the
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- * guarantee for __srcu_read_lock().
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- */
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- smp_mb(); /* D */ /* Pairs with C. */
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-}
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-
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-/*
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- * Enqueue an SRCU callback on the specified srcu_struct structure,
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- * initiating grace-period processing if it is not already running.
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- *
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- * Note that all CPUs must agree that the grace period extended beyond
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- * all pre-existing SRCU read-side critical section. On systems with
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- * more than one CPU, this means that when "func()" is invoked, each CPU
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- * is guaranteed to have executed a full memory barrier since the end of
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- * its last corresponding SRCU read-side critical section whose beginning
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- * preceded the call to call_rcu(). It also means that each CPU executing
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- * an SRCU read-side critical section that continues beyond the start of
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- * "func()" must have executed a memory barrier after the call_rcu()
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- * but before the beginning of that SRCU read-side critical section.
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- * Note that these guarantees include CPUs that are offline, idle, or
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- * executing in user mode, as well as CPUs that are executing in the kernel.
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- *
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- * Furthermore, if CPU A invoked call_rcu() and CPU B invoked the
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- * resulting SRCU callback function "func()", then both CPU A and CPU
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- * B are guaranteed to execute a full memory barrier during the time
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- * interval between the call to call_rcu() and the invocation of "func()".
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- * This guarantee applies even if CPU A and CPU B are the same CPU (but
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- * again only if the system has more than one CPU).
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- *
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- * Of course, these guarantees apply only for invocations of call_srcu(),
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- * srcu_read_lock(), and srcu_read_unlock() that are all passed the same
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- * srcu_struct structure.
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- */
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-void call_srcu(struct srcu_struct *sp, struct rcu_head *head,
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- rcu_callback_t func)
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-{
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- unsigned long flags;
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-
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- head->next = NULL;
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- head->func = func;
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- spin_lock_irqsave(&sp->queue_lock, flags);
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- smp_mb__after_unlock_lock(); /* Caller's prior accesses before GP. */
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- rcu_batch_queue(&sp->batch_queue, head);
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- if (!sp->running) {
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- sp->running = true;
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- queue_delayed_work(system_power_efficient_wq, &sp->work, 0);
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- }
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- spin_unlock_irqrestore(&sp->queue_lock, flags);
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-}
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-EXPORT_SYMBOL_GPL(call_srcu);
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-
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-static void srcu_advance_batches(struct srcu_struct *sp, int trycount);
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-static void srcu_reschedule(struct srcu_struct *sp);
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-
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-/*
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- * Helper function for synchronize_srcu() and synchronize_srcu_expedited().
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- */
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-static void __synchronize_srcu(struct srcu_struct *sp, int trycount)
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-{
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- struct rcu_synchronize rcu;
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- struct rcu_head *head = &rcu.head;
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- bool done = false;
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-
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- RCU_LOCKDEP_WARN(lock_is_held(&sp->dep_map) ||
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- lock_is_held(&rcu_bh_lock_map) ||
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- lock_is_held(&rcu_lock_map) ||
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- lock_is_held(&rcu_sched_lock_map),
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- "Illegal synchronize_srcu() in same-type SRCU (or in RCU) read-side critical section");
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-
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- might_sleep();
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- init_completion(&rcu.completion);
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-
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- head->next = NULL;
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- head->func = wakeme_after_rcu;
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- spin_lock_irq(&sp->queue_lock);
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- smp_mb__after_unlock_lock(); /* Caller's prior accesses before GP. */
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- if (!sp->running) {
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- /* steal the processing owner */
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- sp->running = true;
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- rcu_batch_queue(&sp->batch_check0, head);
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- spin_unlock_irq(&sp->queue_lock);
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-
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- srcu_advance_batches(sp, trycount);
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- if (!rcu_batch_empty(&sp->batch_done)) {
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- BUG_ON(sp->batch_done.head != head);
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- rcu_batch_dequeue(&sp->batch_done);
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- done = true;
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- }
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- /* give the processing owner to work_struct */
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- srcu_reschedule(sp);
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- } else {
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- rcu_batch_queue(&sp->batch_queue, head);
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- spin_unlock_irq(&sp->queue_lock);
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- }
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-
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- if (!done) {
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- wait_for_completion(&rcu.completion);
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- smp_mb(); /* Caller's later accesses after GP. */
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- }
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-
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-}
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-
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-/**
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- * synchronize_srcu - wait for prior SRCU read-side critical-section completion
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- * @sp: srcu_struct with which to synchronize.
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- *
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- * Wait for the count to drain to zero of both indexes. To avoid the
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- * possible starvation of synchronize_srcu(), it waits for the count of
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- * the index=((->completed & 1) ^ 1) to drain to zero at first,
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- * and then flip the completed and wait for the count of the other index.
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- *
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- * Can block; must be called from process context.
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- *
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- * Note that it is illegal to call synchronize_srcu() from the corresponding
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- * SRCU read-side critical section; doing so will result in deadlock.
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- * However, it is perfectly legal to call synchronize_srcu() on one
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- * srcu_struct from some other srcu_struct's read-side critical section,
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- * as long as the resulting graph of srcu_structs is acyclic.
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- *
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- * There are memory-ordering constraints implied by synchronize_srcu().
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- * On systems with more than one CPU, when synchronize_srcu() returns,
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- * each CPU is guaranteed to have executed a full memory barrier since
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- * the end of its last corresponding SRCU-sched read-side critical section
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- * whose beginning preceded the call to synchronize_srcu(). In addition,
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- * each CPU having an SRCU read-side critical section that extends beyond
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- * the return from synchronize_srcu() is guaranteed to have executed a
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- * full memory barrier after the beginning of synchronize_srcu() and before
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- * the beginning of that SRCU read-side critical section. Note that these
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- * guarantees include CPUs that are offline, idle, or executing in user mode,
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- * as well as CPUs that are executing in the kernel.
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- *
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- * Furthermore, if CPU A invoked synchronize_srcu(), which returned
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- * to its caller on CPU B, then both CPU A and CPU B are guaranteed
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- * to have executed a full memory barrier during the execution of
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- * synchronize_srcu(). This guarantee applies even if CPU A and CPU B
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- * are the same CPU, but again only if the system has more than one CPU.
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- *
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- * Of course, these memory-ordering guarantees apply only when
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- * synchronize_srcu(), srcu_read_lock(), and srcu_read_unlock() are
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- * passed the same srcu_struct structure.
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- */
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-void synchronize_srcu(struct srcu_struct *sp)
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-{
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- __synchronize_srcu(sp, (rcu_gp_is_expedited() && !rcu_gp_is_normal())
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- ? SYNCHRONIZE_SRCU_EXP_TRYCOUNT
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- : SYNCHRONIZE_SRCU_TRYCOUNT);
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-}
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-EXPORT_SYMBOL_GPL(synchronize_srcu);
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-
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-/**
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- * synchronize_srcu_expedited - Brute-force SRCU grace period
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- * @sp: srcu_struct with which to synchronize.
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- *
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- * Wait for an SRCU grace period to elapse, but be more aggressive about
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- * spinning rather than blocking when waiting.
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- *
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- * Note that synchronize_srcu_expedited() has the same deadlock and
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- * memory-ordering properties as does synchronize_srcu().
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- */
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-void synchronize_srcu_expedited(struct srcu_struct *sp)
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-{
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- __synchronize_srcu(sp, SYNCHRONIZE_SRCU_EXP_TRYCOUNT);
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-}
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-EXPORT_SYMBOL_GPL(synchronize_srcu_expedited);
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-
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-/**
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- * srcu_barrier - Wait until all in-flight call_srcu() callbacks complete.
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- * @sp: srcu_struct on which to wait for in-flight callbacks.
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- */
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-void srcu_barrier(struct srcu_struct *sp)
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-{
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- synchronize_srcu(sp);
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-}
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-EXPORT_SYMBOL_GPL(srcu_barrier);
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-
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-/**
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- * srcu_batches_completed - return batches completed.
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- * @sp: srcu_struct on which to report batch completion.
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- *
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- * Report the number of batches, correlated with, but not necessarily
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- * precisely the same as, the number of grace periods that have elapsed.
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- */
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-unsigned long srcu_batches_completed(struct srcu_struct *sp)
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-{
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- return sp->completed;
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-}
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-EXPORT_SYMBOL_GPL(srcu_batches_completed);
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-
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-#define SRCU_CALLBACK_BATCH 10
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-#define SRCU_INTERVAL 1
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-
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-/*
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- * Move any new SRCU callbacks to the first stage of the SRCU grace
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- * period pipeline.
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- */
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-static void srcu_collect_new(struct srcu_struct *sp)
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-{
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- if (!rcu_batch_empty(&sp->batch_queue)) {
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- spin_lock_irq(&sp->queue_lock);
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- rcu_batch_move(&sp->batch_check0, &sp->batch_queue);
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- spin_unlock_irq(&sp->queue_lock);
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- }
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-}
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-
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-/*
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- * Core SRCU state machine. Advance callbacks from ->batch_check0 to
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- * ->batch_check1 and then to ->batch_done as readers drain.
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- */
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-static void srcu_advance_batches(struct srcu_struct *sp, int trycount)
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-{
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- int idx = 1 ^ (sp->completed & 1);
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-
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- /*
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- * Because readers might be delayed for an extended period after
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- * fetching ->completed for their index, at any point in time there
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- * might well be readers using both idx=0 and idx=1. We therefore
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- * need to wait for readers to clear from both index values before
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- * invoking a callback.
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- */
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-
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- if (rcu_batch_empty(&sp->batch_check0) &&
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- rcu_batch_empty(&sp->batch_check1))
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- return; /* no callbacks need to be advanced */
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-
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- if (!try_check_zero(sp, idx, trycount))
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- return; /* failed to advance, will try after SRCU_INTERVAL */
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-
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- /*
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- * The callbacks in ->batch_check1 have already done with their
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- * first zero check and flip back when they were enqueued on
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- * ->batch_check0 in a previous invocation of srcu_advance_batches().
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- * (Presumably try_check_zero() returned false during that
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- * invocation, leaving the callbacks stranded on ->batch_check1.)
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- * They are therefore ready to invoke, so move them to ->batch_done.
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- */
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- rcu_batch_move(&sp->batch_done, &sp->batch_check1);
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-
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- if (rcu_batch_empty(&sp->batch_check0))
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- return; /* no callbacks need to be advanced */
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- srcu_flip(sp);
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-
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- /*
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- * The callbacks in ->batch_check0 just finished their
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- * first check zero and flip, so move them to ->batch_check1
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- * for future checking on the other idx.
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- */
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- rcu_batch_move(&sp->batch_check1, &sp->batch_check0);
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-
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- /*
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- * SRCU read-side critical sections are normally short, so check
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- * at least twice in quick succession after a flip.
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- */
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- trycount = trycount < 2 ? 2 : trycount;
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- if (!try_check_zero(sp, idx^1, trycount))
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- return; /* failed to advance, will try after SRCU_INTERVAL */
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-
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|
- /*
|
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|
- * The callbacks in ->batch_check1 have now waited for all
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- * pre-existing readers using both idx values. They are therefore
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- * ready to invoke, so move them to ->batch_done.
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- */
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- rcu_batch_move(&sp->batch_done, &sp->batch_check1);
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-}
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-
|
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|
-/*
|
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|
- * Invoke a limited number of SRCU callbacks that have passed through
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- * their grace period. If there are more to do, SRCU will reschedule
|
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- * the workqueue. Note that needed memory barriers have been executed
|
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- * in this task's context by srcu_readers_active_idx_check().
|
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- */
|
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-static void srcu_invoke_callbacks(struct srcu_struct *sp)
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-{
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- int i;
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- struct rcu_head *head;
|
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|
-
|
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|
- for (i = 0; i < SRCU_CALLBACK_BATCH; i++) {
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- head = rcu_batch_dequeue(&sp->batch_done);
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|
- if (!head)
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|
- break;
|
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|
- local_bh_disable();
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|
- head->func(head);
|
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|
- local_bh_enable();
|
|
|
- }
|
|
|
-}
|
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|
-
|
|
|
-/*
|
|
|
- * Finished one round of SRCU grace period. Start another if there are
|
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|
- * more SRCU callbacks queued, otherwise put SRCU into not-running state.
|
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- */
|
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-static void srcu_reschedule(struct srcu_struct *sp)
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-{
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- bool pending = true;
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-
|
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- if (rcu_batch_empty(&sp->batch_done) &&
|
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|
- rcu_batch_empty(&sp->batch_check1) &&
|
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|
- rcu_batch_empty(&sp->batch_check0) &&
|
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|
- rcu_batch_empty(&sp->batch_queue)) {
|
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|
- spin_lock_irq(&sp->queue_lock);
|
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|
- if (rcu_batch_empty(&sp->batch_done) &&
|
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|
- rcu_batch_empty(&sp->batch_check1) &&
|
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|
- rcu_batch_empty(&sp->batch_check0) &&
|
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- rcu_batch_empty(&sp->batch_queue)) {
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|
- sp->running = false;
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|
- pending = false;
|
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|
- }
|
|
|
- spin_unlock_irq(&sp->queue_lock);
|
|
|
- }
|
|
|
-
|
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|
- if (pending)
|
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|
- queue_delayed_work(system_power_efficient_wq,
|
|
|
- &sp->work, SRCU_INTERVAL);
|
|
|
-}
|
|
|
-
|
|
|
-/*
|
|
|
- * This is the work-queue function that handles SRCU grace periods.
|
|
|
- */
|
|
|
-void process_srcu(struct work_struct *work)
|
|
|
-{
|
|
|
- struct srcu_struct *sp;
|
|
|
-
|
|
|
- sp = container_of(work, struct srcu_struct, work.work);
|
|
|
-
|
|
|
- srcu_collect_new(sp);
|
|
|
- srcu_advance_batches(sp, 1);
|
|
|
- srcu_invoke_callbacks(sp);
|
|
|
- srcu_reschedule(sp);
|
|
|
-}
|
|
|
-EXPORT_SYMBOL_GPL(process_srcu);
|
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|
-
|
|
|
-static int __init srcu_bootup_announce(void)
|
|
|
-{
|
|
|
- pr_info("Classic SRCU implementation.\n");
|
|
|
- return 0;
|
|
|
-}
|
|
|
-early_initcall(srcu_bootup_announce);
|
Paul E. McKenney