xfs: remove nr_to_write writeback windup.

[safe/jmp/linux-2.6] / kernel / rcutiny.c

diff --git a/kernel/rcutiny.c b/kernel/rcutiny.c
index b33ec3a..38729d3 100644 (file)
--- a/kernel/rcutiny.c
+++ b/kernel/rcutiny.c
@@ -44,9 +44,9 @@ struct rcu_ctrlblk {
 };
 
 /* Definition for rcupdate control block. */
-static struct rcu_ctrlblk rcu_ctrlblk = {
-       .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 = {
@@ -54,6 +54,11 @@ static struct rcu_ctrlblk rcu_bh_ctrlblk = {
        .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;
@@ -108,7 +113,8 @@ static int rcu_qsctr_help(struct rcu_ctrlblk *rcp)
  */
 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);
 }
 
@@ -173,20 +179,11 @@ static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp)
  */
 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
@@ -196,7 +193,8 @@ int rcu_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu
  *
  * 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)
 {
@@ -204,12 +202,6 @@ 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().
  */
@@ -235,7 +227,7 @@ static void __call_rcu(struct rcu_head *head,
  */
 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);
 
@@ -253,11 +245,13 @@ void rcu_barrier(void)
 {
        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);
 
@@ -265,11 +259,13 @@ void rcu_barrier_bh(void)
 {
        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);
 
@@ -277,15 +273,19 @@ void rcu_barrier_sched(void)
 {
        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"