linux 2.6.16.38 w/ vs2.0.3-rc1

[linux-2.6.git] / lib / rwsem.c

diff --git a/lib/rwsem.c b/lib/rwsem.c
index a2d725f..62fa4eb 100644 (file)
--- a/lib/rwsem.c
+++ b/lib/rwsem.c
@@ -8,26 +8,6 @@
 #include <linux/init.h>
 #include <linux/module.h>
 
-/*
- * Initialize an rwsem:
- */
-void __init_rwsem(struct rw_semaphore *sem, const char *name,
-                 struct lock_class_key *key)
-{
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-       /*
-        * Make sure we are not reinitializing a held semaphore:
-        */
-       debug_check_no_locks_freed((void *)sem, sizeof(*sem));
-       lockdep_init_map(&sem->dep_map, name, key, 0);
-#endif
-       sem->count = RWSEM_UNLOCKED_VALUE;
-       spin_lock_init(&sem->wait_lock);
-       INIT_LIST_HEAD(&sem->wait_list);
-}
-
-EXPORT_SYMBOL(__init_rwsem);
-
 struct rwsem_waiter {
        struct list_head list;
        struct task_struct *task;
@@ -36,6 +16,17 @@ struct rwsem_waiter {
 #define RWSEM_WAITING_FOR_WRITE        0x00000002
 };
 
+#if RWSEM_DEBUG
+#undef rwsemtrace
+void rwsemtrace(struct rw_semaphore *sem, const char *str)
+{
+       printk("sem=%p\n", sem);
+       printk("(sem)=%08lx\n", sem->count);
+       if (sem->debug)
+               printk("[%d] %s({%08lx})\n", current->pid, str, sem->count);
+}
+#endif
+
 /*
  * handle the lock release when processes blocked on it that can now run
  * - if we come here from up_xxxx(), then:
@@ -54,6 +45,8 @@ __rwsem_do_wake(struct rw_semaphore *sem, int downgrading)
        struct list_head *next;
        signed long oldcount, woken, loop;
 
+       rwsemtrace(sem, "Entering __rwsem_do_wake");
+
        if (downgrading)
                goto dont_wake_writers;
 
@@ -134,6 +127,7 @@ __rwsem_do_wake(struct rw_semaphore *sem, int downgrading)
        next->prev = &sem->wait_list;
 
  out:
+       rwsemtrace(sem, "Leaving __rwsem_do_wake");
        return sem;
 
        /* undo the change to count, but check for a transition 1->0 */
@@ -192,9 +186,13 @@ rwsem_down_read_failed(struct rw_semaphore *sem)
 {
        struct rwsem_waiter waiter;
 
+       rwsemtrace(sem, "Entering rwsem_down_read_failed");
+
        waiter.flags = RWSEM_WAITING_FOR_READ;
        rwsem_down_failed_common(sem, &waiter,
                                RWSEM_WAITING_BIAS - RWSEM_ACTIVE_BIAS);
+
+       rwsemtrace(sem, "Leaving rwsem_down_read_failed");
        return sem;
 }
 
@@ -206,9 +204,12 @@ rwsem_down_write_failed(struct rw_semaphore *sem)
 {
        struct rwsem_waiter waiter;
 
+       rwsemtrace(sem, "Entering rwsem_down_write_failed");
+
        waiter.flags = RWSEM_WAITING_FOR_WRITE;
        rwsem_down_failed_common(sem, &waiter, -RWSEM_ACTIVE_BIAS);
 
+       rwsemtrace(sem, "Leaving rwsem_down_write_failed");
        return sem;
 }
 
@@ -220,6 +221,8 @@ struct rw_semaphore fastcall *rwsem_wake(struct rw_semaphore *sem)
 {
        unsigned long flags;
 
+       rwsemtrace(sem, "Entering rwsem_wake");
+
        spin_lock_irqsave(&sem->wait_lock, flags);
 
        /* do nothing if list empty */
@@ -228,6 +231,8 @@ struct rw_semaphore fastcall *rwsem_wake(struct rw_semaphore *sem)
 
        spin_unlock_irqrestore(&sem->wait_lock, flags);
 
+       rwsemtrace(sem, "Leaving rwsem_wake");
+
        return sem;
 }
 
@@ -240,6 +245,8 @@ struct rw_semaphore fastcall *rwsem_downgrade_wake(struct rw_semaphore *sem)
 {
        unsigned long flags;
 
+       rwsemtrace(sem, "Entering rwsem_downgrade_wake");
+
        spin_lock_irqsave(&sem->wait_lock, flags);
 
        /* do nothing if list empty */
@@ -248,6 +255,7 @@ struct rw_semaphore fastcall *rwsem_downgrade_wake(struct rw_semaphore *sem)
 
        spin_unlock_irqrestore(&sem->wait_lock, flags);
 
+       rwsemtrace(sem, "Leaving rwsem_downgrade_wake");
        return sem;
 }
 
@@ -255,3 +263,6 @@ EXPORT_SYMBOL(rwsem_down_read_failed);
 EXPORT_SYMBOL(rwsem_down_write_failed);
 EXPORT_SYMBOL(rwsem_wake);
 EXPORT_SYMBOL(rwsem_downgrade_wake);
+#if RWSEM_DEBUG
+EXPORT_SYMBOL(rwsemtrace);
+#endif