* Author: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
*
* For detailed explanation of Read-Copy Update mechanism see -
- * Documentation/RCU
+ * Documentation/RCU
*/
-
-#include <linux/types.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/rcupdate.h>
-#include <linux/interrupt.h>
-#include <linux/sched.h>
-#include <linux/module.h>
-#include <linux/completion.h>
#include <linux/moduleparam.h>
+#include <linux/completion.h>
+#include <linux/interrupt.h>
#include <linux/notifier.h>
-#include <linux/cpu.h>
+#include <linux/rcupdate.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
#include <linux/mutex.h>
+#include <linux/sched.h>
+#include <linux/types.h>
+#include <linux/init.h>
#include <linux/time.h>
+#include <linux/cpu.h>
/* Global control variables for rcupdate callback mechanism. */
struct rcu_ctrlblk {
};
/* Definition for rcupdate control block. */
-static struct rcu_ctrlblk rcu_ctrlblk = {
- .rcucblist = NULL,
- .donetail = &rcu_ctrlblk.rcucblist,
- .curtail = &rcu_ctrlblk.rcucblist,
+static struct rcu_ctrlblk rcu_sched_ctrlblk = {
+ .donetail = &rcu_sched_ctrlblk.rcucblist,
+ .curtail = &rcu_sched_ctrlblk.rcucblist,
};
+
static struct rcu_ctrlblk rcu_bh_ctrlblk = {
- .rcucblist = NULL,
- .donetail = &rcu_bh_ctrlblk.rcucblist,
- .curtail = &rcu_bh_ctrlblk.rcucblist,
+ .donetail = &rcu_bh_ctrlblk.rcucblist,
+ .curtail = &rcu_bh_ctrlblk.rcucblist,
};
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+int rcu_scheduler_active __read_mostly;
+EXPORT_SYMBOL_GPL(rcu_scheduler_active);
+#endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
+
#ifdef CONFIG_NO_HZ
static long rcu_dynticks_nesting = 1;
/*
* Helper function for rcu_qsctr_inc() and rcu_bh_qsctr_inc().
- * Also disable irqs to avoid confusion due to interrupt handlers invoking
- * call_rcu().
+ * Also disable irqs to avoid confusion due to interrupt handlers
+ * invoking call_rcu().
*/
static int rcu_qsctr_help(struct rcu_ctrlblk *rcp)
{
return 1;
}
local_irq_restore(flags);
+
return 0;
}
*/
void rcu_sched_qs(int cpu)
{
- if (rcu_qsctr_help(&rcu_ctrlblk) + rcu_qsctr_help(&rcu_bh_ctrlblk))
+ if (rcu_qsctr_help(&rcu_sched_ctrlblk) +
+ rcu_qsctr_help(&rcu_bh_ctrlblk))
raise_softirq(RCU_SOFTIRQ);
}
*/
static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp)
{
- unsigned long flags;
struct rcu_head *next, *list;
+ unsigned long flags;
/* If no RCU callbacks ready to invoke, just return. */
if (&rcp->rcucblist == rcp->donetail)
*/
static void rcu_process_callbacks(struct softirq_action *unused)
{
- __rcu_process_callbacks(&rcu_ctrlblk);
+ __rcu_process_callbacks(&rcu_sched_ctrlblk);
__rcu_process_callbacks(&rcu_bh_ctrlblk);
}
/*
- * Null function to handle CPU being onlined. Longer term, we want to
- * make TINY_RCU avoid using rcupdate.c, but later...
- */
-int rcu_cpu_notify(struct notifier_block *self,
- unsigned long action, void *hcpu)
-{
- return NOTIFY_OK;
-}
-
-/*
* Wait for a grace period to elapse. But it is illegal to invoke
* synchronize_sched() from within an RCU read-side critical section.
* Therefore, any legal call to synchronize_sched() is a quiescent
*
* Cool, huh? (Due to Josh Triplett.)
*
- * But we want to make this a static inline later.
+ * But we want to make this a static inline later. The cond_resched()
+ * currently makes this problematic.
*/
void synchronize_sched(void)
{
}
EXPORT_SYMBOL_GPL(synchronize_sched);
-void synchronize_rcu_bh(void)
-{
- synchronize_sched();
-}
-EXPORT_SYMBOL_GPL(synchronize_rcu_bh);
-
/*
* Helper function for call_rcu() and call_rcu_bh().
*/
head->func = func;
head->next = NULL;
+
local_irq_save(flags);
*rcp->curtail = head;
rcp->curtail = &head->next;
* period. But since we have but one CPU, that would be after any
* quiescent state.
*/
-void call_rcu(struct rcu_head *head,
- void (*func)(struct rcu_head *rcu))
+void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
{
- __call_rcu(head, func, &rcu_ctrlblk);
+ __call_rcu(head, func, &rcu_sched_ctrlblk);
}
EXPORT_SYMBOL_GPL(call_rcu);
* Post an RCU bottom-half callback to be invoked after any subsequent
* quiescent state.
*/
-void call_rcu_bh(struct rcu_head *head,
- void (*func)(struct rcu_head *rcu))
+void call_rcu_bh(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
{
__call_rcu(head, func, &rcu_bh_ctrlblk);
}
{
struct rcu_synchronize rcu;
+ init_rcu_head_on_stack(&rcu.head);
init_completion(&rcu.completion);
/* Will wake me after RCU finished. */
call_rcu(&rcu.head, wakeme_after_rcu);
/* Wait for it. */
wait_for_completion(&rcu.completion);
+ destroy_rcu_head_on_stack(&rcu.head);
}
EXPORT_SYMBOL_GPL(rcu_barrier);
{
struct rcu_synchronize rcu;
+ init_rcu_head_on_stack(&rcu.head);
init_completion(&rcu.completion);
/* Will wake me after RCU finished. */
call_rcu_bh(&rcu.head, wakeme_after_rcu);
/* Wait for it. */
wait_for_completion(&rcu.completion);
+ destroy_rcu_head_on_stack(&rcu.head);
}
EXPORT_SYMBOL_GPL(rcu_barrier_bh);
{
struct rcu_synchronize rcu;
+ init_rcu_head_on_stack(&rcu.head);
init_completion(&rcu.completion);
/* Will wake me after RCU finished. */
call_rcu_sched(&rcu.head, wakeme_after_rcu);
/* Wait for it. */
wait_for_completion(&rcu.completion);
+ destroy_rcu_head_on_stack(&rcu.head);
}
EXPORT_SYMBOL_GPL(rcu_barrier_sched);
-void __rcu_init(void)
+void __init rcu_init(void)
{
open_softirq(RCU_SOFTIRQ, rcu_process_callbacks);
}
+
+#include "rcutiny_plugin.h"
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff