Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb-2.6

[safe/jmp/linux-2.6] / Documentation / atomic_ops.txt

diff --git a/Documentation/atomic_ops.txt b/Documentation/atomic_ops.txt
index f20c10c..ac4d471 100644 (file)
--- a/Documentation/atomic_ops.txt
+++ b/Documentation/atomic_ops.txt
@@ -186,7 +186,8 @@ If the atomic value v is not equal to u, this function adds a to v, and
 returns non zero. If v is equal to u then it returns zero. This is done as
 an atomic operation.
 
-atomic_add_unless requires explicit memory barriers around the operation.
+atomic_add_unless requires explicit memory barriers around the operation
+unless it fails (returns 0).
 
 atomic_inc_not_zero, equivalent to atomic_add_unless(v, 1, 0)
 
@@ -228,10 +229,10 @@ kernel.  It is the use of atomic counters to implement reference
 counting, and it works such that once the counter falls to zero it can
 be guaranteed that no other entity can be accessing the object:
 
-static void obj_list_add(struct obj *obj)
+static void obj_list_add(struct obj *obj, struct list_head *head)
 {
        obj->active = 1;
-       list_add(&obj->list);
+       list_add(&obj->list, head);
 }
 
 static void obj_list_del(struct obj *obj)
@@ -319,7 +320,7 @@ counter decrement would not become globally visible until the
 obj->active update does.
 
 As a historical note, 32-bit Sparc used to only allow usage of
-24-bits of it's atomic_t type.  This was because it used 8 bits
+24-bits of its atomic_t type.  This was because it used 8 bits
 as a spinlock for SMP safety.  Sparc32 lacked a "compare and swap"
 type instruction.  However, 32-bit Sparc has since been moved over
 to a "hash table of spinlocks" scheme, that allows the full 32-bit