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-rw-r--r--kernel/srcu.c53
1 files changed, 34 insertions, 19 deletions
diff --git a/kernel/srcu.c b/kernel/srcu.c
index 818d7d9aa03c..2980da3fd509 100644
--- a/kernel/srcu.c
+++ b/kernel/srcu.c
@@ -30,10 +30,33 @@
#include <linux/preempt.h>
#include <linux/rcupdate.h>
#include <linux/sched.h>
-#include <linux/slab.h>
#include <linux/smp.h>
#include <linux/srcu.h>
+static int init_srcu_struct_fields(struct srcu_struct *sp)
+{
+ sp->completed = 0;
+ mutex_init(&sp->mutex);
+ sp->per_cpu_ref = alloc_percpu(struct srcu_struct_array);
+ return sp->per_cpu_ref ? 0 : -ENOMEM;
+}
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+
+int __init_srcu_struct(struct srcu_struct *sp, const char *name,
+ struct lock_class_key *key)
+{
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ /* Don't re-initialize a lock while it is held. */
+ debug_check_no_locks_freed((void *)sp, sizeof(*sp));
+ lockdep_init_map(&sp->dep_map, name, key, 0);
+#endif /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
+ return init_srcu_struct_fields(sp);
+}
+EXPORT_SYMBOL_GPL(__init_srcu_struct);
+
+#else /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */
+
/**
* init_srcu_struct - initialize a sleep-RCU structure
* @sp: structure to initialize.
@@ -44,13 +67,12 @@
*/
int init_srcu_struct(struct srcu_struct *sp)
{
- sp->completed = 0;
- mutex_init(&sp->mutex);
- sp->per_cpu_ref = alloc_percpu(struct srcu_struct_array);
- return (sp->per_cpu_ref ? 0 : -ENOMEM);
+ return init_srcu_struct_fields(sp);
}
EXPORT_SYMBOL_GPL(init_srcu_struct);
+#endif /* #else #ifdef CONFIG_DEBUG_LOCK_ALLOC */
+
/*
* srcu_readers_active_idx -- returns approximate number of readers
* active on the specified rank of per-CPU counters.
@@ -100,15 +122,12 @@ void cleanup_srcu_struct(struct srcu_struct *sp)
}
EXPORT_SYMBOL_GPL(cleanup_srcu_struct);
-/**
- * srcu_read_lock - register a new reader for an SRCU-protected structure.
- * @sp: srcu_struct in which to register the new reader.
- *
+/*
* Counts the new reader in the appropriate per-CPU element of the
* srcu_struct. Must be called from process context.
* Returns an index that must be passed to the matching srcu_read_unlock().
*/
-int srcu_read_lock(struct srcu_struct *sp)
+int __srcu_read_lock(struct srcu_struct *sp)
{
int idx;
@@ -120,31 +139,27 @@ int srcu_read_lock(struct srcu_struct *sp)
preempt_enable();
return idx;
}
-EXPORT_SYMBOL_GPL(srcu_read_lock);
+EXPORT_SYMBOL_GPL(__srcu_read_lock);
-/**
- * srcu_read_unlock - unregister a old reader from an SRCU-protected structure.
- * @sp: srcu_struct in which to unregister the old reader.
- * @idx: return value from corresponding srcu_read_lock().
- *
+/*
* Removes the count for the old reader from the appropriate per-CPU
* element of the srcu_struct. Note that this may well be a different
* CPU than that which was incremented by the corresponding srcu_read_lock().
* Must be called from process context.
*/
-void srcu_read_unlock(struct srcu_struct *sp, int idx)
+void __srcu_read_unlock(struct srcu_struct *sp, int idx)
{
preempt_disable();
srcu_barrier(); /* ensure compiler won't misorder critical section. */
per_cpu_ptr(sp->per_cpu_ref, smp_processor_id())->c[idx]--;
preempt_enable();
}
-EXPORT_SYMBOL_GPL(srcu_read_unlock);
+EXPORT_SYMBOL_GPL(__srcu_read_unlock);
/*
* Helper function for synchronize_srcu() and synchronize_srcu_expedited().
*/
-void __synchronize_srcu(struct srcu_struct *sp, void (*sync_func)(void))
+static void __synchronize_srcu(struct srcu_struct *sp, void (*sync_func)(void))
{
int idx;