sh: convert /proc/cpu/aligmnent, /proc/cpu/kernel_alignment to seq_file

[safe/jmp/linux-2.6] / kernel / rcutree_plugin.h

diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index 6525021..ef2a58c 100644 (file)
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -304,21 +304,25 @@ static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp)
  * parent is to remove the need for rcu_read_unlock_special() to
  * make more than two attempts to acquire the target rcu_node's lock.
  *
+ * Returns 1 if there was previously a task blocking the current grace
+ * period on the specified rcu_node structure.
+ *
  * The caller must hold rnp->lock with irqs disabled.
  */
-static void rcu_preempt_offline_tasks(struct rcu_state *rsp,
-                                     struct rcu_node *rnp,
-                                     struct rcu_data *rdp)
+static int rcu_preempt_offline_tasks(struct rcu_state *rsp,
+                                    struct rcu_node *rnp,
+                                    struct rcu_data *rdp)
 {
        int i;
        struct list_head *lp;
        struct list_head *lp_root;
+       int retval = rcu_preempted_readers(rnp);
        struct rcu_node *rnp_root = rcu_get_root(rsp);
        struct task_struct *tp;
 
        if (rnp == rnp_root) {
                WARN_ONCE(1, "Last CPU thought to be offlined?");
-               return;  /* Shouldn't happen: at least one CPU online. */
+               return 0;  /* Shouldn't happen: at least one CPU online. */
        }
        WARN_ON_ONCE(rnp != rdp->mynode &&
                     (!list_empty(&rnp->blocked_tasks[0]) ||
@@ -342,6 +346,8 @@ static void rcu_preempt_offline_tasks(struct rcu_state *rsp,
                        spin_unlock(&rnp_root->lock); /* irqs remain disabled */
                }
        }
+
+       return retval;
 }
 
 /*
@@ -393,6 +399,17 @@ void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
 EXPORT_SYMBOL_GPL(call_rcu);
 
 /*
+ * Wait for an rcu-preempt grace period.  We are supposed to expedite the
+ * grace period, but this is the crude slow compatability hack, so just
+ * invoke synchronize_rcu().
+ */
+void synchronize_rcu_expedited(void)
+{
+       synchronize_rcu();
+}
+EXPORT_SYMBOL_GPL(synchronize_rcu_expedited);
+
+/*
  * Check to see if there is any immediate preemptable-RCU-related work
  * to be done.
  */
@@ -410,6 +427,15 @@ static int rcu_preempt_needs_cpu(int cpu)
        return !!per_cpu(rcu_preempt_data, cpu).nxtlist;
 }
 
+/**
+ * rcu_barrier - Wait until all in-flight call_rcu() callbacks complete.
+ */
+void rcu_barrier(void)
+{
+       _rcu_barrier(&rcu_preempt_state, call_rcu);
+}
+EXPORT_SYMBOL_GPL(rcu_barrier);
+
 /*
  * Initialize preemptable RCU's per-CPU data.
  */
@@ -419,14 +445,18 @@ static void __cpuinit rcu_preempt_init_percpu_data(int cpu)
 }
 
 /*
+ * Move preemptable RCU's callbacks to ->orphan_cbs_list.
+ */
+static void rcu_preempt_send_cbs_to_orphanage(void)
+{
+       rcu_send_cbs_to_orphanage(&rcu_preempt_state);
+}
+
+/*
  * Initialize preemptable RCU's state structures.
  */
 static void __init __rcu_init_preempt(void)
 {
-       int i;                  /* All used by RCU_INIT_FLAVOR(). */
-       int j;
-       struct rcu_node *rnp;
-
        RCU_INIT_FLAVOR(&rcu_preempt_state, rcu_preempt_data);
 }
 
@@ -508,12 +538,15 @@ static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp)
 
 /*
  * Because preemptable RCU does not exist, it never needs to migrate
- * tasks that were blocked within RCU read-side critical sections.
+ * tasks that were blocked within RCU read-side critical sections, and
+ * such non-existent tasks cannot possibly have been blocking the current
+ * grace period.
  */
-static void rcu_preempt_offline_tasks(struct rcu_state *rsp,
-                                     struct rcu_node *rnp,
-                                     struct rcu_data *rdp)
+static int rcu_preempt_offline_tasks(struct rcu_state *rsp,
+                                    struct rcu_node *rnp,
+                                    struct rcu_data *rdp)
 {
+       return 0;
 }
 
 /*
@@ -552,6 +585,16 @@ void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu))
 EXPORT_SYMBOL_GPL(call_rcu);
 
 /*
+ * Wait for an rcu-preempt grace period, but make it happen quickly.
+ * But because preemptable RCU does not exist, map to rcu-sched.
+ */
+void synchronize_rcu_expedited(void)
+{
+       synchronize_sched_expedited();
+}
+EXPORT_SYMBOL_GPL(synchronize_rcu_expedited);
+
+/*
  * Because preemptable RCU does not exist, it never has any work to do.
  */
 static int rcu_preempt_pending(int cpu)
@@ -568,6 +611,16 @@ static int rcu_preempt_needs_cpu(int cpu)
 }
 
 /*
+ * Because preemptable RCU does not exist, rcu_barrier() is just
+ * another name for rcu_barrier_sched().
+ */
+void rcu_barrier(void)
+{
+       rcu_barrier_sched();
+}
+EXPORT_SYMBOL_GPL(rcu_barrier);
+
+/*
  * Because preemptable RCU does not exist, there is no per-CPU
  * data to initialize.
  */
@@ -576,6 +629,13 @@ static void __cpuinit rcu_preempt_init_percpu_data(int cpu)
 }
 
 /*
+ * Because there is no preemptable RCU, there are no callbacks to move.
+ */
+static void rcu_preempt_send_cbs_to_orphanage(void)
+{
+}
+
+/*
  * Because preemptable RCU does not exist, it need not be initialized.
  */
 static void __init __rcu_init_preempt(void)